Sample records for computer-aided polyp detection

  1. Improved computer-aided detection of small polyps in CT colonography using interpolation for curvature estimationa

    PubMed Central

    Liu, Jiamin; Kabadi, Suraj; Van Uitert, Robert; Petrick, Nicholas; Deriche, Rachid; Summers, Ronald M.

    2011-01-01

    Purpose: Surface curvatures are important geometric features for the computer-aided analysis and detection of polyps in CT colonography (CTC). However, the general kernel approach for curvature computation can yield erroneous results for small polyps and for polyps that lie on haustral folds. Those erroneous curvatures will reduce the performance of polyp detection. This paper presents an analysis of interpolation’s effect on curvature estimation for thin structures and its application on computer-aided detection of small polyps in CTC. Methods: The authors demonstrated that a simple technique, image interpolation, can improve the accuracy of curvature estimation for thin structures and thus significantly improve the sensitivity of small polyp detection in CTC. Results: Our experiments showed that the merits of interpolating included more accurate curvature values for simulated data, and isolation of polyps near folds for clinical data. After testing on a large clinical data set, it was observed that sensitivities with linear, quadratic B-spline and cubic B-spline interpolations significantly improved the sensitivity for small polyp detection. Conclusions: The image interpolation can improve the accuracy of curvature estimation for thin structures and thus improve the computer-aided detection of small polyps in CTC. PMID:21859029

  2. Colonic polyps: application value of computer-aided detection in computed tomographic colonography.

    PubMed

    Zhang, Hui-Mao; Guo, Wei; Liu, Gui-Feng; An, Dong-Hong; Gao, Shuo-Hui; Sun, Li-Bo; Yang, Hai-Shan

    2011-02-01

    Colonic polyps are frequently encountered in clinics. Computed tomographic colonography (CTC), as a painless and quick detection, has high values in clinics. In this study, we evaluated the application value of computer-aided detection (CAD) in CTC detection of colonic polyps in the Chinese population. CTC was performed with a GE 64-row multidetector computed tomography (MDCT) scanner. Data of 50 CTC patients (39 patients positive for at least one polyp of ≥ 0.5 cm in size and the other 11 patients negative by endoscopic detection) were retrospectively reviewed first without computer-aided detection (CAD) and then with CAD by four radiologists (two were experienced and another two inexperienced) blinded to colonoscopy findings. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of detected colonic polyps, as well as the areas under the ROC curves (Az value) with and without CAD were calculated. CAD increased the overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the colonic polyps detected by experienced and inexperienced readers. The sensitivity in detecting small polyps (5 - 9 mm) with CAD in experienced and inexperienced readers increased from 82% and 44% to 93% and 82%, respectively (P > 0.05 and P < 0.001). With the use of CAD, the overall false positive rate and false negative rate for the detection of polyps by experienced and inexperienced readers decreased in different degrees. Among 13 sessile polyps not detected by CAD, two were ≥ 1.0 cm, eleven were 5 - 9 mm in diameter, and nine were flat-shaped lesions. The application of CAD in combination with CTC can increase the ability to detect colonic polyps, particularly for inexperienced readers. However, CAD is of limited value for the detection of flat polyps.

  3. Wavelet method for CT colonography computer-aided polyp detection.

    PubMed

    Li, Jiang; Van Uitert, Robert; Yao, Jianhua; Petrick, Nicholas; Franaszek, Marek; Huang, Adam; Summers, Ronald M

    2008-08-01

    Computed tomographic colonography (CTC) computer aided detection (CAD) is a new method to detect colon polyps. Colonic polyps are abnormal growths that may become cancerous. Detection and removal of colonic polyps, particularly larger ones, has been shown to reduce the incidence of colorectal cancer. While high sensitivities and low false positive rates are consistently achieved for the detection of polyps sized 1 cm or larger, lower sensitivities and higher false positive rates occur when the goal of CAD is to identify "medium"-sized polyps, 6-9 mm in diameter. Such medium-sized polyps may be important for clinical patient management. We have developed a wavelet-based postprocessor to reduce false positives for this polyp size range. We applied the wavelet-based postprocessor to CTC CAD findings from 44 patients in whom 45 polyps with sizes of 6-9 mm were found at segmentally unblinded optical colonoscopy and visible on retrospective review of the CT colonography images. Prior to the application of the wavelet-based postprocessor, the CTC CAD system detected 33 of the polyps (sensitivity 73.33%) with 12.4 false positives per patient, a sensitivity comparable to that of expert radiologists. Fourfold cross validation with 5000 bootstraps showed that the wavelet-based postprocessor could reduce the false positives by 56.61% (p <0.001), to 5.38 per patient (95% confidence interval [4.41, 6.34]), without significant sensitivity degradation (32/45, 71.11%, 95% confidence interval [66.39%, 75.74%], p=0.1713). We conclude that this wavelet-based postprocessor can substantially reduce the false positive rate of our CTC CAD for this important polyp size range.

  4. Deep learning of contrast-coated serrated polyps for computer-aided detection in CT colonography

    NASA Astrophysics Data System (ADS)

    Näppi, Janne J.; Pickhardt, Perry; Kim, David H.; Hironaka, Toru; Yoshida, Hiroyuki

    2017-03-01

    Serrated polyps were previously believed to be benign lesions with no cancer potential. However, recent studies have revealed a novel molecular pathway where also serrated polyps can develop into colorectal cancer. CT colonography (CTC) can detect serrated polyps using the radiomic biomarker of contrast coating, but this requires expertise from the reader and current computer-aided detection (CADe) systems have not been designed to detect the contrast coating. The purpose of this study was to develop a novel CADe method that makes use of deep learning to detect serrated polyps based on their contrast-coating biomarker in CTC. In the method, volumetric shape-based features are used to detect polyp sites over soft-tissue and fecal-tagging surfaces of the colon. The detected sites are imaged using multi-angular 2D image patches. A deep convolutional neural network (DCNN) is used to review the image patches for the presence of polyps. The DCNN-based polyp-likelihood estimates are merged into an aggregate likelihood index where highest values indicate the presence of a polyp. For pilot evaluation, the proposed DCNN-CADe method was evaluated with a 10-fold cross-validation scheme using 101 colonoscopy-confirmed cases with 144 biopsy-confirmed serrated polyps from a CTC screening program, where the patients had been prepared for CTC with saline laxative and fecal tagging by barium and iodine-based diatrizoate. The average per-polyp sensitivity for serrated polyps >=6 mm in size was 93+/-7% at 0:8+/-1:8 false positives per patient on average. The detection accuracy was substantially higher that of a conventional CADe system. Our results indicate that serrated polyps can be detected automatically at high accuracy in CTC.

  5. High-performance computer aided detection system for polyp detection in CT colonography with fluid and fecal tagging

    NASA Astrophysics Data System (ADS)

    Liu, Jiamin; Wang, Shijun; Kabadi, Suraj; Summers, Ronald M.

    2009-02-01

    CT colonography (CTC) is a feasible and minimally invasive method for the detection of colorectal polyps and cancer screening. Computer-aided detection (CAD) of polyps has improved consistency and sensitivity of virtual colonoscopy interpretation and reduced interpretation burden. A CAD system typically consists of four stages: (1) image preprocessing including colon segmentation; (2) initial detection generation; (3) feature selection; and (4) detection classification. In our experience, three existing problems limit the performance of our current CAD system. First, highdensity orally administered contrast agents in fecal-tagging CTC have scatter effects on neighboring tissues. The scattering manifests itself as an artificial elevation in the observed CT attenuation values of the neighboring tissues. This pseudo-enhancement phenomenon presents a problem for the application of computer-aided polyp detection, especially when polyps are submerged in the contrast agents. Second, general kernel approach for surface curvature computation in the second stage of our CAD system could yield erroneous results for thin structures such as small (6-9 mm) polyps and for touching structures such as polyps that lie on haustral folds. Those erroneous curvatures will reduce the sensitivity of polyp detection. The third problem is that more than 150 features are selected from each polyp candidate in the third stage of our CAD system. These high dimensional features make it difficult to learn a good decision boundary for detection classification and reduce the accuracy of predictions. Therefore, an improved CAD system for polyp detection in CTC data is proposed by introducing three new techniques. First, a scale-based scatter correction algorithm is applied to reduce pseudo-enhancement effects in the image pre-processing stage. Second, a cubic spline interpolation method is utilized to accurately estimate curvatures for initial detection generation. Third, a new dimensionality reduction classifier, diffusion map and local linear embedding (DMLLE), is developed for classification and false positives (FP) reduction. Performance of the improved CAD system is evaluated and compared with our existing CAD system (without applying those techniques) using CT scans of 1186 patients. These scans are divided into a training set and a test set. The sensitivity of the improved CAD system increased 18% on training data at a rate of 5 FPs per patient and 15% on test data at a rate of 5 FPs per patient. Our results indicated that the improved CAD system achieved significantly better performance on medium-sized colonic adenomas with higher sensitivity and lower FP rate in CTC.

  6. Strategies for Improved Interpretation of Computer-Aided Detections for CT Colonography Utilizing Distributed Human Intelligence

    PubMed Central

    McKenna, Matthew T.; Wang, Shijun; Nguyen, Tan B.; Burns, Joseph E.; Petrick, Nicholas; Summers, Ronald M.

    2012-01-01

    Computer-aided detection (CAD) systems have been shown to improve the diagnostic performance of CT colonography (CTC) in the detection of premalignant colorectal polyps. Despite the improvement, the overall system is not optimal. CAD annotations on true lesions are incorrectly dismissed, and false positives are misinterpreted as true polyps. Here, we conduct an observer performance study utilizing distributed human intelligence in the form of anonymous knowledge workers (KWs) to investigate human performance in classifying polyp candidates under different presentation strategies. We evaluated 600 polyp candidates from 50 patients, each case having at least one polyp • 6 mm, from a large database of CTC studies. Each polyp candidate was labeled independently as a true or false polyp by 20 KWs and an expert radiologist. We asked each labeler to determine whether the candidate was a true polyp after looking at a single 3D-rendered image of the candidate and after watching a video fly-around of the candidate. We found that distributed human intelligence improved significantly when presented with the additional information in the video fly-around. We noted that performance degraded with increasing interpretation time and increasing difficulty, but distributed human intelligence performed better than our CAD classifier for “easy” and “moderate” polyp candidates. Further, we observed numerous parallels between the expert radiologist and the KWs. Both showed similar improvement in classification moving from single-image to video interpretation. Additionally, difficulty estimates obtained from the KWs using an expectation maximization algorithm correlated well with the difficulty rating assigned by the expert radiologist. Our results suggest that distributed human intelligence is a powerful tool that will aid in the development of CAD for CTC. PMID:22705287

  7. Strategies for improved interpretation of computer-aided detections for CT colonography utilizing distributed human intelligence.

    PubMed

    McKenna, Matthew T; Wang, Shijun; Nguyen, Tan B; Burns, Joseph E; Petrick, Nicholas; Summers, Ronald M

    2012-08-01

    Computer-aided detection (CAD) systems have been shown to improve the diagnostic performance of CT colonography (CTC) in the detection of premalignant colorectal polyps. Despite the improvement, the overall system is not optimal. CAD annotations on true lesions are incorrectly dismissed, and false positives are misinterpreted as true polyps. Here, we conduct an observer performance study utilizing distributed human intelligence in the form of anonymous knowledge workers (KWs) to investigate human performance in classifying polyp candidates under different presentation strategies. We evaluated 600 polyp candidates from 50 patients, each case having at least one polyp ≥6 mm, from a large database of CTC studies. Each polyp candidate was labeled independently as a true or false polyp by 20 KWs and an expert radiologist. We asked each labeler to determine whether the candidate was a true polyp after looking at a single 3D-rendered image of the candidate and after watching a video fly-around of the candidate. We found that distributed human intelligence improved significantly when presented with the additional information in the video fly-around. We noted that performance degraded with increasing interpretation time and increasing difficulty, but distributed human intelligence performed better than our CAD classifier for "easy" and "moderate" polyp candidates. Further, we observed numerous parallels between the expert radiologist and the KWs. Both showed similar improvement in classification moving from single-image to video interpretation. Additionally, difficulty estimates obtained from the KWs using an expectation maximization algorithm correlated well with the difficulty rating assigned by the expert radiologist. Our results suggest that distributed human intelligence is a powerful tool that will aid in the development of CAD for CTC. Copyright © 2012. Published by Elsevier B.V.

  8. Optimizing computer-aided colonic polyp detection for CT colonography by evolving the Pareto front1

    PubMed Central

    Li, Jiang; Huang, Adam; Yao, Jack; Liu, Jiamin; Van Uitert, Robert L.; Petrick, Nicholas; Summers, Ronald M.

    2009-01-01

    A multiobjective genetic algorithm is designed to optimize a computer-aided detection (CAD) system for identifying colonic polyps. Colonic polyps appear as elliptical protrusions on the inner surface of the colon. Curvature-based features for colonic polyp detection have proved to be successful in several CT colonography (CTC) CAD systems. Our CTC CAD program uses a sequential classifier to form initial polyp detections on the colon surface. The classifier utilizes a set of thresholds on curvature-based features to cluster suspicious colon surface regions into polyp candidates. The thresholds were previously chosen experimentally by using feature histograms. The chosen thresholds were effective for detecting polyps sized 10 mm or larger in diameter. However, many medium-sized polyps, 6–9 mm in diameter, were missed in the initial detection procedure. In this paper, the task of finding optimal thresholds as a multiobjective optimization problem was formulated, and a genetic algorithm to solve it was utilized by evolving the Pareto front of the Pareto optimal set. The new CTC CAD system was tested on 792 patients. The sensitivities of the optimized system improved significantly, from 61.68% to 74.71% with an increase of 13.03% (95% CI [6.57%, 19.5%], p=7.78×10−5) for the size category of 6–9 mm polyps, from 65.02% to 77.4% with an increase of 12.38% (95% CI [6.23%, 18.53%], p=7.95×10−5) for polyps 6 mm or larger, and from 82.2% to 90.58% with an increase of 8.38% (95%CI [0.75%, 16%], p=0.03) for polyps 8 mm or larger at comparable false positive rates. The sensitivities of the optimized system are nearly equivalent to those of expert radiologists. PMID:19235388

  9. Computer-aided detection of initial polyp candidates with level set-based adaptive convolution

    NASA Astrophysics Data System (ADS)

    Zhu, Hongbin; Duan, Chaijie; Liang, Zhengrong

    2009-02-01

    In order to eliminate or weaken the interference between different topological structures on the colon wall, adaptive and normalized convolution methods were used to compute the first and second order spatial derivatives of computed tomographic colonography images, which is the beginning of various geometric analyses. However, the performance of such methods greatly depends on the single-layer representation of the colon wall, which is called the starting layer (SL) in the following text. In this paper, we introduce a level set-based adaptive convolution (LSAC) method to compute the spatial derivatives, in which the level set method is employed to determine a more reasonable SL. The LSAC was applied to a computer-aided detection (CAD) scheme to detect the initial polyp candidates, and experiments showed that it benefits the CAD scheme in both the detection sensitivity and specificity as compared to our previous work.

  10. A study of oral contrast coating on the surface of polyps: an implication for computer-aided detection and classification of polyps

    NASA Astrophysics Data System (ADS)

    Singh, Harmanpreet; Li, Lihong C.; Pomeroy, Marc; Pickhardt, Perry J.; Barish, Matthew A.; Harrington, Donald P.; Liang, Zhengrong

    2017-03-01

    Accurate identification of polyps is the ultimate goal of Computed Tomography Colonography (CTC). While oral contrast agents were originally used to tag stool and fluid for the ultimate goal of CTC, recently their effect on coating the surface of polyps has been observed. This study aims to evaluate (1) the frequency at which the oral contrast adhered to polyp surfaces and (2) if there was a difference in contrast adherence with respect to diverse polyp types. To eliminate gravity as a factor in this study, the polyps in contact with tagged fluid pools, particularly on the bottom of the colon wall were excluded. A total of 150 polyps were selected under the above condition from a CTC database and screened for any adherent contrast on the luminal edge. Among the total, 53% of the screened polyps had adherent contrast. Serrated adenomas and hyperplastic polyps had a higher tagging percentage, 77.80% and 62.50% respectively, than tubular adenomas and tubulovillous adenomas, 44.40% and 43% respectively. Other factors that were analyzed for the effect on coating include size and location of the polyps. The higher tagging percentage of serrated adenomas and hyperplastic polyps may be due to their similar cellular features. The average size of the polyps was 8.9 mm. When the polyps were separated by size into small (5-9mm) and large (10-26mm) groups, the large group had a higher tagging percentage. The polyp types were also classified by location with the major findings being: 1) Tubular adenomas were present in all segments of the colon and 2) that serrated adenomas were present at a higher percentage in the proximal colon. These findings shall facilitate characterizing tagging agents and improve computer aided detection and classification of polyps via CTC.

  11. Distributed Human Intelligence for Colonic Polyp Classification in Computer-aided Detection for CT Colonography

    PubMed Central

    Nguyen, Tan B.; Wang, Shijun; Anugu, Vishal; Rose, Natalie; McKenna, Matthew; Petrick, Nicholas; Burns, Joseph E.

    2012-01-01

    Purpose: To assess the diagnostic performance of distributed human intelligence for the classification of polyp candidates identified with computer-aided detection (CAD) for computed tomographic (CT) colonography. Materials and Methods: This study was approved by the institutional Office of Human Subjects Research. The requirement for informed consent was waived for this HIPAA-compliant study. CT images from 24 patients, each with at least one polyp of 6 mm or larger, were analyzed by using CAD software to identify 268 polyp candidates. Twenty knowledge workers (KWs) from a crowdsourcing platform labeled each polyp candidate as a true or false polyp. Two trials involving 228 KWs were conducted to assess reproducibility. Performance was assessed by comparing the area under the receiver operating characteristic curve (AUC) of KWs with the AUC of CAD for polyp classification. Results: The detection-level AUC for KWs was 0.845 ± 0.045 (standard error) in trial 1 and 0.855 ± 0.044 in trial 2. These were not significantly different from the AUC for CAD, which was 0.859 ± 0.043. When polyp candidates were stratified by difficulty, KWs performed better than CAD on easy detections; AUCs were 0.951 ± 0.032 in trial 1, 0.966 ± 0.027 in trial 2, and 0.877 ± 0.048 for CAD (P = .039 for trial 2). KWs who participated in both trials showed a significant improvement in performance going from trial 1 to trial 2; AUCs were 0.759 ± 0.052 in trial 1 and 0.839 ± 0.046 in trial 2 (P = .041). Conclusion: The performance of distributed human intelligence is not significantly different from that of CAD for colonic polyp classification. © RSNA, 2012 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11110938/-/DC1 PMID:22274839

  12. Computer-aided detection of colorectal polyps: can it improve sensitivity of less-experienced readers? Preliminary findings.

    PubMed

    Baker, Mark E; Bogoni, Luca; Obuchowski, Nancy A; Dass, Chandra; Kendzierski, Renee M; Remer, Erick M; Einstein, David M; Cathier, Pascal; Jerebko, Anna; Lakare, Sarang; Blum, Andrew; Caroline, Dina F; Macari, Michael

    2007-10-01

    To determine whether computer-aided detection (CAD) applied to computed tomographic (CT) colonography can help improve sensitivity of polyp detection by less-experienced radiologist readers, with colonoscopy or consensus used as the reference standard. The release of the CT colonographic studies was approved by the individual institutional review boards of each institution. Institutions from the United States were HIPAA compliant. Written informed consent was waived at all institutions. The CT colonographic studies in 30 patients from six institutions were collected; 24 images depicted at least one confirmed polyp 6 mm or larger (39 total polyps) and six depicted no polyps. By using an investigational software package, seven less-experienced readers from two institutions evaluated the CT colonographic images and marked or scored polyps by using a five-point scale before and after CAD. The time needed to interpret the CT colonographic findings without CAD and then to re-evaluate them with CAD was recorded. For each reader, the McNemar test, adjusted for clustered data, was used to compare sensitivities for readers without and with CAD; a Wilcoxon signed-rank test was used to analyze the number of false-positive results per patient. The average sensitivity of the seven readers for polyp detection was significantly improved with CAD-from 0.810 to 0.908 (P=.0152). The number of false-positive results per patient without and with CAD increased from 0.70 to 0.96 (95% confidence interval for the increase: -0.39, 0.91). The mean total time for the readings was 17 minutes 54 seconds; for interpretation of CT colonographic findings alone, the mean time was 14 minutes 16 seconds; and for review of CAD findings, the mean time was 3 minutes 38 seconds. Results of this feasibility study suggest that CAD for CT colonography significantly improves per-polyp detection for less-experienced readers. Copyright (c) RSNA, 2007.

  13. CT colonography: influence of 3D viewing and polyp candidate features on interpretation with computer-aided detection.

    PubMed

    Shi, Rong; Schraedley-Desmond, Pamela; Napel, Sandy; Olcott, Eric W; Jeffrey, R Brooke; Yee, Judy; Zalis, Michael E; Margolis, Daniel; Paik, David S; Sherbondy, Anthony J; Sundaram, Padmavathi; Beaulieu, Christopher F

    2006-06-01

    To retrospectively determine if three-dimensional (3D) viewing improves radiologists' accuracy in classifying true-positive (TP) and false-positive (FP) polyp candidates identified with computer-aided detection (CAD) and to determine candidate polyp features that are associated with classification accuracy, with known polyps serving as the reference standard. Institutional review board approval and informed consent were obtained; this study was HIPAA compliant. Forty-seven computed tomographic (CT) colonography data sets were obtained in 26 men and 10 women (age range, 42-76 years). Four radiologists classified 705 polyp candidates (53 TP candidates, 652 FP candidates) identified with CAD; initially, only two-dimensional images were used, but these were later supplemented with 3D rendering. Another radiologist unblinded to colonoscopy findings characterized the features of each candidate, assessed colon distention and preparation, and defined the true nature of FP candidates. Receiver operating characteristic curves were used to compare readers' performance, and repeated-measures analysis of variance was used to test features that affect interpretation. Use of 3D viewing improved classification accuracy for three readers and increased the area under the receiver operating characteristic curve to 0.96-0.97 (P<.001). For TP candidates, maximum polyp width (P=.038), polyp height (P=.019), and preparation (P=.004) significantly affected accuracy. For FP candidates, colonic segment (P=.007), attenuation (P<.001), surface smoothness (P<.001), distention (P=.034), preparation (P<.001), and true nature of candidate lesions (P<.001) significantly affected accuracy. Use of 3D viewing increases reader accuracy in the classification of polyp candidates identified with CAD. Polyp size and examination quality are significantly associated with accuracy. Copyright (c) RSNA, 2006.

  14. Automated image-based colon cleansing for laxative-free CT colonography computer-aided polyp detection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Linguraru, Marius George; Panjwani, Neil; Fletcher, Joel G.

    2011-12-15

    Purpose: To evaluate the performance of a computer-aided detection (CAD) system for detecting colonic polyps at noncathartic computed tomography colonography (CTC) in conjunction with an automated image-based colon cleansing algorithm. Methods: An automated colon cleansing algorithm was designed to detect and subtract tagged-stool, accounting for heterogeneity and poor tagging, to be used in conjunction with a colon CAD system. The method is locally adaptive and combines intensity, shape, and texture analysis with probabilistic optimization. CTC data from cathartic-free bowel preparation were acquired for testing and training the parameters. Patients underwent various colonic preparations with barium or Gastroview in divided dosesmore » over 48 h before scanning. No laxatives were administered and no dietary modifications were required. Cases were selected from a polyp-enriched cohort and included scans in which at least 90% of the solid stool was visually estimated to be tagged and each colonic segment was distended in either the prone or supine view. The CAD system was run comparatively with and without the stool subtraction algorithm. Results: The dataset comprised 38 CTC scans from prone and/or supine scans of 19 patients containing 44 polyps larger than 10 mm (22 unique polyps, if matched between prone and supine scans). The results are robust on fine details around folds, thin-stool linings on the colonic wall, near polyps and in large fluid/stool pools. The sensitivity of the CAD system is 70.5% per polyp at a rate of 5.75 false positives/scan without using the stool subtraction module. This detection improved significantly (p = 0.009) after automated colon cleansing on cathartic-free data to 86.4% true positive rate at 5.75 false positives/scan. Conclusions: An automated image-based colon cleansing algorithm designed to overcome the challenges of the noncathartic colon significantly improves the sensitivity of colon CAD by approximately 15%.« less

  15. CT Colonography with Computer-aided Detection: Recognizing the Causes of False-Positive Reader Results

    PubMed Central

    Dachman, Abraham H.; Wroblewski, Kristen; Vannier, Michael W.; Horne, John M.

    2014-01-01

    Computed tomography (CT) colonography is a screening modality used to detect colonic polyps before they progress to colorectal cancer. Computer-aided detection (CAD) is designed to decrease errors of detection by finding and displaying polyp candidates for evaluation by the reader. CT colonography CAD false-positive results are common and have numerous causes. The relative frequency of CAD false-positive results and their effect on reader performance on the basis of a 19-reader, 100-case trial shows that the vast majority of CAD false-positive results were dismissed by readers. Many CAD false-positive results are easily disregarded, including those that result from coarse mucosa, reconstruction, peristalsis, motion, streak artifacts, diverticulum, rectal tubes, and lipomas. CAD false-positive results caused by haustral folds, extracolonic candidates, diminutive lesions (<6 mm), anal papillae, internal hemorrhoids, varices, extrinsic compression, and flexural pseudotumors are almost always recognized and disregarded. The ileocecal valve and tagged stool are common sources of CAD false-positive results associated with reader false-positive results. Nondismissable CAD soft-tissue polyp candidates larger than 6 mm are another common cause of reader false-positive results that may lead to further evaluation with follow-up CT colonography or optical colonoscopy. Strategies for correctly evaluating CAD polyp candidates are important to avoid pitfalls from common sources of CAD false-positive results. ©RSNA, 2014 PMID:25384290

  16. Automated matching of supine and prone colonic polyps based on PCA and SVMs

    NASA Astrophysics Data System (ADS)

    Wang, Shijun; Van Uitert, Robert L.; Summers, Ronald M.

    2008-03-01

    Computed tomographic colonography (CTC) is a feasible and minimally invasive method for the detection of colorectal polyps and cancer screening. In current practice, a patient will be scanned twice during the CTC examination - once supine and once prone. In order to assist the radiologists in evaluating colon polyp candidates in both scans, we expect the computer aided detection (CAD) system can provide not only the locations of suspicious polyps, but also the possible matched pairs of polyps in two scans. In this paper, we propose a new automated matching method based on the extracted features of polyps by using principal component analysis (PCA) and Support Vector Machines (SVMs). Our dataset comes from the 104 CT scans of 52 patients with supine and prone positions collected from three medical centers. From it we constructed two groups of matched polyp candidates according to the size of true polyps: group A contains 12 true polyp pairs (> 9 mm) and 454 false pairs; group B contains 24 true polyp pairs (6-9 mm) and 514 false pairs. By using PCA, we reduced the dimensions of original data (with 157 attributes) to 30 dimensions. We did leave-one-patient-out test on the two groups of data. ROC analysis shows that it is easier to match bigger polyps than that of smaller polyps. On group A data, when false alarm probability is 0.18, the sensitivity of SVM achieves 0.83 which shows that automated matching of polyp candidates is practicable for clinical applications.

  17. Registration of central paths and colonic polyps between supine and prone scans in computed tomography colonography: Pilot study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li Ping; Napel, Sandy; Acar, Burak

    2004-10-01

    Computed tomography colonography (CTC) is a minimally invasive method that allows the evaluation of the colon wall from CT sections of the abdomen/pelvis. The primary goal of CTC is to detect colonic polyps, precursors to colorectal cancer. Because imperfect cleansing and distension can cause portions of the colon wall to be collapsed, covered with water, and/or covered with retained stool, patients are scanned in both prone and supine positions. We believe that both reading efficiency and computer aided detection (CAD) of CTC images can be improved by accurate registration of data from the supine and prone positions. We developed amore » two-stage approach that first registers the colonic central paths using a heuristic and automated algorithm and then matches polyps or polyp candidates (CAD hits) by a statistical approach. We evaluated the registration algorithm on 24 patient cases. After path registration, the mean misalignment distance between prone and supine identical anatomic landmarks was reduced from 47.08 to 12.66 mm, a 73% improvement. The polyp registration algorithm was specifically evaluated using eight patient cases for which radiologists identified polyps separately for both supine and prone data sets, and then manually registered corresponding pairs. The algorithm correctly matched 78% of these pairs without user input. The algorithm was also applied to the 30 highest-scoring CAD hits in the prone and supine scans and showed a success rate of 50% in automatically registering corresponding polyp pairs. Finally, we computed the average number of CAD hits that need to be manually compared in order to find the correct matches among the top 30 CAD hits. With polyp registration, the average number of comparisons was 1.78 per polyp, as opposed to 4.28 comparisons without polyp registration.« less

  18. Deep ensemble learning of virtual endoluminal views for polyp detection in CT colonography

    NASA Astrophysics Data System (ADS)

    Umehara, Kensuke; Näppi, Janne J.; Hironaka, Toru; Regge, Daniele; Ishida, Takayuki; Yoshida, Hiroyuki

    2017-03-01

    Robust training of a deep convolutional neural network (DCNN) requires a very large number of annotated datasets that are currently not available in CT colonography (CTC). We previously demonstrated that deep transfer learning provides an effective approach for robust application of a DCNN in CTC. However, at high detection accuracy, the differentiation of small polyps from non-polyps was still challenging. In this study, we developed and evaluated a deep ensemble learning (DEL) scheme for reviewing of virtual endoluminal images to improve the performance of computer-aided detection (CADe) of polyps in CTC. Nine different types of image renderings were generated from virtual endoluminal images of polyp candidates detected by a conventional CADe system. Eleven DCNNs that represented three types of publically available pre-trained DCNN models were re-trained by transfer learning to identify polyps from the virtual endoluminal images. A DEL scheme that determines the final detected polyps by a review of the nine types of VE images was developed by combining the DCNNs using a random forest classifier as a meta-classifier. For evaluation, we sampled 154 CTC cases from a large CTC screening trial and divided the cases randomly into a training dataset and a test dataset. At 3.9 falsepositive (FP) detections per patient on average, the detection sensitivities of the conventional CADe system, the highestperforming single DCNN, and the DEL scheme were 81.3%, 90.7%, and 93.5%, respectively, for polyps ≥6 mm in size. For small polyps, the DEL scheme reduced the number of false positives by up to 83% over that of using a single DCNN alone. These preliminary results indicate that the DEL scheme provides an effective approach for improving the polyp detection performance of CADe in CTC, especially for small polyps.

  19. 77 FR 21574 - Prospective Grant of Exclusive License: Method for Segmenting Medical Images and Detecting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-10

    ... methods help solve imaging problems such as image ``leakage,'' which causes distortion, overloads datasets... enhance detection. This is helpful to identify harmful features such as precancerous polyps or other anomalies. The field of use may be limited to ``computer aided detection in colonography.'' The prospective...

  20. Assessment of the Incremental Benefit of Computer-Aided Detection (CAD) for Interpretation of CT Colonography by Experienced and Inexperienced Readers

    PubMed Central

    Boone, Darren; Mallett, Susan; McQuillan, Justine; Taylor, Stuart A.; Altman, Douglas G.; Halligan, Steve

    2015-01-01

    Objectives To quantify the incremental benefit of computer-assisted-detection (CAD) for polyps, for inexperienced readers versus experienced readers of CT colonography. Methods 10 inexperienced and 16 experienced radiologists interpreted 102 colonography studies unassisted and with CAD utilised in a concurrent paradigm. They indicated any polyps detected on a study sheet. Readers’ interpretations were compared against a ground-truth reference standard: 46 studies were normal and 56 had at least one polyp (132 polyps in total). The primary study outcome was the difference in CAD net benefit (a combination of change in sensitivity and change in specificity with CAD, weighted towards sensitivity) for detection of patients with polyps. Results Inexperienced readers’ per-patient sensitivity rose from 39.1% to 53.2% with CAD and specificity fell from 94.1% to 88.0%, both statistically significant. Experienced readers’ sensitivity rose from 57.5% to 62.1% and specificity fell from 91.0% to 88.3%, both non-significant. Net benefit with CAD assistance was significant for inexperienced readers but not for experienced readers: 11.2% (95%CI 3.1% to 18.9%) versus 3.2% (95%CI -1.9% to 8.3%) respectively. Conclusions Concurrent CAD resulted in a significant net benefit when used by inexperienced readers to identify patients with polyps by CT colonography. The net benefit was nearly four times the magnitude of that observed for experienced readers. Experienced readers did not benefit significantly from concurrent CAD. PMID:26355745

  1. Combining heterogeneous features for colonic polyp detection in CTC based on semi-definite programming

    NASA Astrophysics Data System (ADS)

    Wang, Shijun; Yao, Jianhua; Petrick, Nicholas A.; Summers, Ronald M.

    2009-02-01

    Colon cancer is the second leading cause of cancer-related deaths in the United States. Computed tomographic colonography (CTC) combined with a computer aided detection system provides a feasible combination for improving colonic polyps detection and increasing the use of CTC for colon cancer screening. To distinguish true polyps from false positives, various features extracted from polyp candidates have been proposed. Most of these features try to capture the shape information of polyp candidates or neighborhood knowledge about the surrounding structures (fold, colon wall, etc.). In this paper, we propose a new set of shape descriptors for polyp candidates based on statistical curvature information. These features, called histogram of curvature features, are rotation, translation and scale invariant and can be treated as complementing our existing feature set. Then in order to make full use of the traditional features (defined as group A) and the new features (group B) which are highly heterogeneous, we employed a multiple kernel learning method based on semi-definite programming to identify an optimized classification kernel based on the combined set of features. We did leave-one-patient-out test on a CTC dataset which contained scans from 50 patients (with 90 6-9mm polyp detections). Experimental results show that a support vector machine (SVM) based on the combined feature set and the semi-definite optimization kernel achieved higher FROC performance compared to SVMs using the two groups of features separately. At a false positive per patient rate of 7, the sensitivity on 6-9mm polyps using the combined features improved from 0.78 (Group A) and 0.73 (Group B) to 0.82 (p<=0.01).

  2. Max-AUC Feature Selection in Computer-Aided Detection of Polyps in CT Colonography

    PubMed Central

    Xu, Jian-Wu; Suzuki, Kenji

    2014-01-01

    We propose a feature selection method based on a sequential forward floating selection (SFFS) procedure to improve the performance of a classifier in computerized detection of polyps in CT colonography (CTC). The feature selection method is coupled with a nonlinear support vector machine (SVM) classifier. Unlike the conventional linear method based on Wilks' lambda, the proposed method selected the most relevant features that would maximize the area under the receiver operating characteristic curve (AUC), which directly maximizes classification performance, evaluated based on AUC value, in the computer-aided detection (CADe) scheme. We presented two variants of the proposed method with different stopping criteria used in the SFFS procedure. The first variant searched all feature combinations allowed in the SFFS procedure and selected the subsets that maximize the AUC values. The second variant performed a statistical test at each step during the SFFS procedure, and it was terminated if the increase in the AUC value was not statistically significant. The advantage of the second variant is its lower computational cost. To test the performance of the proposed method, we compared it against the popular stepwise feature selection method based on Wilks' lambda for a colonic-polyp database (25 polyps and 2624 nonpolyps). We extracted 75 morphologic, gray-level-based, and texture features from the segmented lesion candidate regions. The two variants of the proposed feature selection method chose 29 and 7 features, respectively. Two SVM classifiers trained with these selected features yielded a 96% by-polyp sensitivity at false-positive (FP) rates of 4.1 and 6.5 per patient, respectively. Experiments showed a significant improvement in the performance of the classifier with the proposed feature selection method over that with the popular stepwise feature selection based on Wilks' lambda that yielded 18.0 FPs per patient at the same sensitivity level. PMID:24608058

  3. Max-AUC feature selection in computer-aided detection of polyps in CT colonography.

    PubMed

    Xu, Jian-Wu; Suzuki, Kenji

    2014-03-01

    We propose a feature selection method based on a sequential forward floating selection (SFFS) procedure to improve the performance of a classifier in computerized detection of polyps in CT colonography (CTC). The feature selection method is coupled with a nonlinear support vector machine (SVM) classifier. Unlike the conventional linear method based on Wilks' lambda, the proposed method selected the most relevant features that would maximize the area under the receiver operating characteristic curve (AUC), which directly maximizes classification performance, evaluated based on AUC value, in the computer-aided detection (CADe) scheme. We presented two variants of the proposed method with different stopping criteria used in the SFFS procedure. The first variant searched all feature combinations allowed in the SFFS procedure and selected the subsets that maximize the AUC values. The second variant performed a statistical test at each step during the SFFS procedure, and it was terminated if the increase in the AUC value was not statistically significant. The advantage of the second variant is its lower computational cost. To test the performance of the proposed method, we compared it against the popular stepwise feature selection method based on Wilks' lambda for a colonic-polyp database (25 polyps and 2624 nonpolyps). We extracted 75 morphologic, gray-level-based, and texture features from the segmented lesion candidate regions. The two variants of the proposed feature selection method chose 29 and 7 features, respectively. Two SVM classifiers trained with these selected features yielded a 96% by-polyp sensitivity at false-positive (FP) rates of 4.1 and 6.5 per patient, respectively. Experiments showed a significant improvement in the performance of the classifier with the proposed feature selection method over that with the popular stepwise feature selection based on Wilks' lambda that yielded 18.0 FPs per patient at the same sensitivity level.

  4. Efficient seeding and defragmentation of curvature streamlines for colonic polyp detection

    NASA Astrophysics Data System (ADS)

    Zhao, Lingxiao; Botha, Charl P.; Truyen, Roel; Vos, Frans M.; Post, Frits H.

    2008-03-01

    Many computer aided diagnosis (CAD) schemes have been developed for colon cancer detection using Virtual Colonoscopy (VC). In earlier work, we developed an automatic polyp detection method integrating flow visualization techniques, that forms part of the CAD functionality of an existing Virtual Colonoscopy pipeline. Curvature streamlines were used to characterize polyp surface shape. Features derived from curvature streamlines correlated highly with true polyp detections. During testing with a large number of patient data sets, we found that the correlation between streamline features and true polyps could be affected by noise and our streamline generation technique. The seeding and spacing constraints and CT noise could lead to streamline fragmentation, which reduced the discriminating power of our streamline features. In this paper, we present two major improvements of our curvature streamline generation. First, we adapted our streamline seeding strategy to the local surface properties and made the streamline generation faster. It generates a significantly smaller number of seeds but still results in a comparable and suitable streamline distribution. Second, based on our observation that longer streamlines are better surface shape descriptors, we improved our streamline tracing algorithm to produce longer streamlines. Our improved techniques are more effcient and also guide the streamline geometry to correspond better to colonic surface shape. These two adaptations support a robust and high correlation between our streamline features and true positive detections and lead to better polyp detection results.

  5. Automatic Polyp Detection via A Novel Unified Bottom-up and Top-down Saliency Approach.

    PubMed

    Yuan, Yixuan; Li, Dengwang; Meng, Max Q-H

    2017-07-31

    In this paper, we propose a novel automatic computer-aided method to detect polyps for colonoscopy videos. To find the perceptually and semantically meaningful salient polyp regions, we first segment images into multilevel superpixels. Each level corresponds to different sizes of superpixels. Rather than adopting hand-designed features to describe these superpixels in images, we employ sparse autoencoder (SAE) to learn discriminative features in an unsupervised way. Then a novel unified bottom-up and top-down saliency method is proposed to detect polyps. In the first stage, we propose a weak bottom-up (WBU) saliency map by fusing the contrast based saliency and object-center based saliency together. The contrast based saliency map highlights image parts that show different appearances compared with surrounding areas while the object-center based saliency map emphasizes the center of the salient object. In the second stage, a strong classifier with Multiple Kernel Boosting (MKB) is learned to calculate the strong top-down (STD) saliency map based on samples directly from the obtained multi-level WBU saliency maps. We finally integrate these two stage saliency maps from all levels together to highlight polyps. Experiment results achieve 0.818 recall for saliency calculation, validating the effectiveness of our method. Extensive experiments on public polyp datasets demonstrate that the proposed saliency algorithm performs favorably against state-of-the-art saliency methods to detect polyps.

  6. Massive-training artificial neural network (MTANN) for reduction of false positives in computer-aided detection of polyps: Suppression of rectal tubes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Suzuki, Kenji; Yoshida, Hiroyuki; Naeppi, Janne

    2006-10-15

    One of the limitations of the current computer-aided detection (CAD) of polyps in CT colonography (CTC) is a relatively large number of false-positive (FP) detections. Rectal tubes (RTs) are one of the typical sources of FPs because a portion of a RT, especially a portion of a bulbous tip, often exhibits a cap-like shape that closely mimics the appearance of a small polyp. Radiologists can easily recognize and dismiss RT-induced FPs; thus, they may lose their confidence in CAD as an effective tool if the CAD scheme generates such ''obvious'' FPs due to RTs consistently. In addition, RT-induced FPs maymore » distract radiologists from less common true positives in the rectum. Therefore, removal RT-induced FPs as well as other types of FPs is desirable while maintaining a high sensitivity in the detection of polyps. We developed a three-dimensional (3D) massive-training artificial neural network (MTANN) for distinction between polyps and RTs in 3D CTC volumetric data. The 3D MTANN is a supervised volume-processing technique which is trained with input CTC volumes and the corresponding ''teaching'' volumes. The teaching volume for a polyp contains a 3D Gaussian distribution, and that for a RT contains zeros for enhancement of polyps and suppression of RTs, respectively. For distinction between polyps and nonpolyps including RTs, a 3D scoring method based on a 3D Gaussian weighting function is applied to the output of the trained 3D MTANN. Our database consisted of CTC examinations of 73 patients, scanned in both supine and prone positions (146 CTC data sets in total), with optical colonoscopy as a reference standard for the presence of polyps. Fifteen patients had 28 polyps, 15 of which were 5-9 mm and 13 were 10-25 mm in size. These CTC cases were subjected to our previously reported CAD scheme that included centerline-based segmentation of the colon, shape-based detection of polyps, and reduction of FPs by use of a Bayesian neural network based on geometric and texture features. Application of this CAD scheme yielded 96.4% (27/28) by-polyp sensitivity with 3.1 (224/73) FPs per patient, among which 20 FPs were caused by RTs. To eliminate the FPs due to RTs and possibly other normal structures, we trained a 3D MTANN with ten representative polyps and ten RTs, and applied the trained 3D MTANN to the above CAD true- and false-positive detections. In the output volumes of the 3D MTANN, polyps were represented by distributions of bright voxels, whereas RTs and other normal structures partly similar to RTs appeared as darker voxels, indicating the ability of the 3D MTANN to suppress RTs as well as other normal structures effectively. Application of the 3D MTANN to the CAD detections showed that the 3D MTANN eliminated all RT-induced 20 FPs, as well as 53 FPs due to other causes, without removal of any true positives. Overall, the 3D MTANN was able to reduce the FP rate of the CAD scheme from 3.1 to 2.1 FPs per patient (33% reduction), while the original by-polyp sensitivity of 96.4% was maintained.« less

  7. CT colonography: investigation of the optimum reader paradigm by using computer-aided detection software.

    PubMed

    Taylor, Stuart A; Charman, Susan C; Lefere, Philippe; McFarland, Elizabeth G; Paulson, Erik K; Yee, Judy; Aslam, Rizwan; Barlow, John M; Gupta, Arun; Kim, David H; Miller, Chad M; Halligan, Steve

    2008-02-01

    To prospectively compare the diagnostic performance and time efficiency of both second and concurrent computer-aided detection (CAD) reading paradigms for retrospectively obtained computed tomographic (CT) colonography data sets by using consensus reading (three radiologists) of colonoscopic findings as a reference standard. Ethical permission, HIPAA compliance (for U.S. institutions), and patient consent were obtained from all institutions for use of CT colonography data sets in this study. Ten radiologists each read 25 CT colonography data sets (12 men, 13 women; mean age, 61 years) containing 69 polyps (28 were 1-5 mm, 41 were >or=6 mm) by using workstations integrated with CAD software. Reading was randomized to either "second read" CAD (applied only after initial unassisted assessment) or "concurrent read" CAD (applied at the start of assessment). Data sets were reread 6 weeks later by using the opposing paradigm. Polyp sensitivity and reading times were compared by using multilevel logistic and linear regression, respectively. Receiver operating characteristic (ROC) curves were generated. Compared with the unassisted read, odds of improved polyp (>or=6 mm) detection were 1.5 (95% confidence interval [CI]: 1.0, 2.2) and 1.3 (95% CI: 0.9, 1.9) by using CAD as second and concurrent reader, respectively. Detection odds by using CAD concurrently were 0.87 (95% CI: 0.59, 1.3) and 0.76 (95% CI: 0.57, 1.01) those of second read CAD, excluding and including polyps 1-5 mm, respectively. The concurrent read took 2.9 minutes (95% CI: -3.8, -1.9) less than did second read. The mean areas under the ROC curve (95% CI) for the unassisted read, second read CAD, and concurrent read CAD were 0.83 (95% CI: 0.78, 0.87), 0.86 (95% CI: 0.82, 0.90), and 0.88 (95% CI: 0.83, 0.92), respectively. CAD is more time efficient when used concurrently than when used as a second reader, with similar sensitivity for polyps 6 mm or larger. However, use of second read CAD maximizes sensitivity, particularly for smaller lesions. (c) RSNA, 2007.

  8. A comparison of blood vessel features and local binary patterns for colorectal polyp classification

    NASA Astrophysics Data System (ADS)

    Gross, Sebastian; Stehle, Thomas; Behrens, Alexander; Auer, Roland; Aach, Til; Winograd, Ron; Trautwein, Christian; Tischendorf, Jens

    2009-02-01

    Colorectal cancer is the third leading cause of cancer deaths in the United States of America for both women and men. By means of early detection, the five year survival rate can be up to 90%. Polyps can to be grouped into three different classes: hyperplastic, adenomatous, and carcinomatous polyps. Hyperplastic polyps are benign and are not likely to develop into cancer. Adenomas, on the other hand, are known to grow into cancer (adenoma-carcinoma sequence). Carcinomas are fully developed cancers and can be easily distinguished from adenomas and hyperplastic polyps. A recent narrow band imaging (NBI) study by Tischendorf et al. has shown that hyperplastic polyps and adenomas can be discriminated by their blood vessel structure. We designed a computer-aided system for the differentiation between hyperplastic and adenomatous polyps. Our development aim is to provide the medical practitioner with an additional objective interpretation of the available image data as well as a confidence measure for the classification. We propose classification features calculated on the basis of the extracted blood vessel structure. We use the combined length of the detected blood vessels, the average perimeter of the vessels and their average gray level value. We achieve a successful classification rate of more than 90% on 102 polyps from our polyp data base. The classification results based on these features are compared to the results of Local Binary Patterns (LBP). The results indicate that the implemented features are superior to LBP.

  9. Combining Statistical and Geometric Features for Colonic Polyp Detection in CTC Based on Multiple Kernel Learning

    PubMed Central

    Wang, Shijun; Yao, Jianhua; Petrick, Nicholas; Summers, Ronald M.

    2010-01-01

    Colon cancer is the second leading cause of cancer-related deaths in the United States. Computed tomographic colonography (CTC) combined with a computer aided detection system provides a feasible approach for improving colonic polyps detection and increasing the use of CTC for colon cancer screening. To distinguish true polyps from false positives, various features extracted from polyp candidates have been proposed. Most of these traditional features try to capture the shape information of polyp candidates or neighborhood knowledge about the surrounding structures (fold, colon wall, etc.). In this paper, we propose a new set of shape descriptors for polyp candidates based on statistical curvature information. These features called histograms of curvature features are rotation, translation and scale invariant and can be treated as complementing existing feature set. Then in order to make full use of the traditional geometric features (defined as group A) and the new statistical features (group B) which are highly heterogeneous, we employed a multiple kernel learning method based on semi-definite programming to learn an optimized classification kernel from the two groups of features. We conducted leave-one-patient-out test on a CTC dataset which contained scans from 66 patients. Experimental results show that a support vector machine (SVM) based on the combined feature set and the semi-definite optimization kernel achieved higher FROC performance compared to SVMs using the two groups of features separately. At a false positive per scan rate of 5, the sensitivity of the SVM using the combined features improved from 0.77 (Group A) and 0.73 (Group B) to 0.83 (p ≤ 0.01). PMID:20953299

  10. Computer-aided marginal artery detection on computed tomographic colonography

    NASA Astrophysics Data System (ADS)

    Wei, Zhuoshi; Yao, Jianhua; Wang, Shijun; Liu, Jiamin; Summers, Ronald M.

    2012-03-01

    Computed tomographic colonography (CTC) is a minimally invasive technique for colonic polyps and cancer screening. The marginal artery of the colon, also known as the marginal artery of Drummond, is the blood vessel that connects the inferior mesenteric artery with the superior mesenteric artery. The marginal artery runs parallel to the colon for its entire length, providing the blood supply to the colon. Detecting the marginal artery may benefit computer-aided detection (CAD) of colonic polyp. It can be used to identify teniae coli based on their anatomic spatial relationship. It can also serve as an alternative marker for colon localization, in case of colon collapse and inability to directly compute the endoluminal centerline. This paper proposes an automatic method for marginal artery detection on CTC. To the best of our knowledge, this is the first work presented for this purpose. Our method includes two stages. The first stage extracts the blood vessels in the abdominal region. The eigenvalue of Hessian matrix is used to detect line-like structures in the images. The second stage is to reduce the false positives in the first step. We used two different masks to exclude the false positive vessel regions. One is a dilated colon mask which is obtained by colon segmentation. The other is an eroded visceral fat mask which is obtained by fat segmentation in the abdominal region. We tested our method on a CTC dataset with 6 cases. Using ratio-of-overlap with manual labeling of the marginal artery as the standard-of-reference, our method yielded true positive, false positive and false negative fractions of 89%, 33%, 11%, respectively.

  11. Histogram-based adaptive gray level scaling for texture feature classification of colorectal polyps

    NASA Astrophysics Data System (ADS)

    Pomeroy, Marc; Lu, Hongbing; Pickhardt, Perry J.; Liang, Zhengrong

    2018-02-01

    Texture features have played an ever increasing role in computer aided detection (CADe) and diagnosis (CADx) methods since their inception. Texture features are often used as a method of false positive reduction for CADe packages, especially for detecting colorectal polyps and distinguishing them from falsely tagged residual stool and healthy colon wall folds. While texture features have shown great success there, the performance of texture features for CADx have lagged behind primarily because of the more similar features among different polyps types. In this paper, we present an adaptive gray level scaling and compare it to the conventional equal-spacing of gray level bins. We use a dataset taken from computed tomography colonography patients, with 392 polyp regions of interest (ROIs) identified and have a confirmed diagnosis through pathology. Using the histogram information from the entire ROI dataset, we generate the gray level bins such that each bin contains roughly the same number of voxels Each image ROI is the scaled down to two different numbers of gray levels, using both an equal spacing of Hounsfield units for each bin, and our adaptive method. We compute a set of texture features from the scaled images including 30 gray level co-occurrence matrix (GLCM) features and 11 gray level run length matrix (GLRLM) features. Using a random forest classifier to distinguish between hyperplastic polyps and all others (adenomas and adenocarcinomas), we find that the adaptive gray level scaling can improve performance based on the area under the receiver operating characteristic curve by up to 4.6%.

  12. Crowd-assisted polyp annotation of virtual colonoscopy videos

    NASA Astrophysics Data System (ADS)

    Park, Ji Hwan; Nadeem, Saad; Marino, Joseph; Baker, Kevin; Barish, Matthew; Kaufman, Arie

    2018-03-01

    Virtual colonoscopy (VC) allows a radiologist to navigate through a 3D colon model reconstructed from a computed tomography scan of the abdomen, looking for polyps, the precursors of colon cancer. Polyps are seen as protrusions on the colon wall and haustral folds, visible in the VC y-through videos. A complete review of the colon surface requires full navigation from the rectum to the cecum in antegrade and retrograde directions, which is a tedious task that takes an average of 30 minutes. Crowdsourcing is a technique for non-expert users to perform certain tasks, such as image or video annotation. In this work, we use crowdsourcing for the examination of complete VC y-through videos for polyp annotation by non-experts. The motivation for this is to potentially help the radiologist reach a diagnosis in a shorter period of time, and provide a stronger confirmation of the eventual diagnosis. The crowdsourcing interface includes an interactive tool for the crowd to annotate suspected polyps in the video with an enclosing box. Using our work flow, we achieve an overall polyps-per-patient sensitivity of 87.88% (95.65% for polyps >=5mm and 70% for polyps <5mm). We also demonstrate the efficacy and effectiveness of a non-expert user in detecting and annotating polyps and discuss their possibility in aiding radiologists in VC examinations.

  13. Accurate Classification of Diminutive Colorectal Polyps Using Computer-Aided Analysis.

    PubMed

    Chen, Peng-Jen; Lin, Meng-Chiung; Lai, Mei-Ju; Lin, Jung-Chun; Lu, Henry Horng-Shing; Tseng, Vincent S

    2018-02-01

    Narrow-band imaging is an image-enhanced form of endoscopy used to observed microstructures and capillaries of the mucosal epithelium which allows for real-time prediction of histologic features of colorectal polyps. However, narrow-band imaging expertise is required to differentiate hyperplastic from neoplastic polyps with high levels of accuracy. We developed and tested a system of computer-aided diagnosis with a deep neural network (DNN-CAD) to analyze narrow-band images of diminutive colorectal polyps. We collected 1476 images of neoplastic polyps and 681 images of hyperplastic polyps, obtained from the picture archiving and communications system database in a tertiary hospital in Taiwan. Histologic findings from the polyps were also collected and used as the reference standard. The images and data were used to train the DNN. A test set of images (96 hyperplastic and 188 neoplastic polyps, smaller than 5 mm), obtained from patients who underwent colonoscopies from March 2017 through August 2017, was then used to test the diagnostic ability of the DNN-CAD vs endoscopists (2 expert and 4 novice), who were asked to classify the images of the test set as neoplastic or hyperplastic. Their classifications were compared with findings from histologic analysis. The primary outcome measures were diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic time. The accuracy, sensitivity, specificity, PPV, NPV, and diagnostic time were compared among DNN-CAD, the novice endoscopists, and the expert endoscopists. The study was designed to detect a difference of 10% in accuracy by a 2-sided McNemar test. In the test set, the DNN-CAD identified neoplastic or hyperplastic polyps with 96.3% sensitivity, 78.1% specificity, a PPV of 89.6%, and a NPV of 91.5%. Fewer than half of the novice endoscopists classified polyps with a NPV of 90% (their NPVs ranged from 73.9% to 84.0%). DNN-CAD classified polyps as neoplastic or hyperplastic in 0.45 ± 0.07 seconds-shorter than the time required by experts (1.54 ± 1.30 seconds) and nonexperts (1.77 ± 1.37 seconds) (both P < .001). DNN-CAD classified polyps with perfect intra-observer agreement (kappa score of 1). There was a low level of intra-observer and inter-observer agreement in classification among endoscopists. We developed a system called DNN-CAD to identify neoplastic or hyperplastic colorectal polyps less than 5 mm. The system classified polyps with a PPV of 89.6%, and a NPV of 91.5%, and in a shorter time than endoscopists. This deep-learning model has potential for not only endoscopic image recognition but for other forms of medical image analysis, including sonography, computed tomography, and magnetic resonance images. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

  14. Texture-based CAD improves diagnosis for low-dose CT colonography

    NASA Astrophysics Data System (ADS)

    Liang, Zhengrong; Cohen, Harris; Posniak, Erica; Fiore, Eddie; Wang, Zigang; Li, Bin; Andersen, Joseph; Harrington, Donald

    2008-03-01

    Computed tomography (CT)-based virtual colonoscopy or CT colonography (CTC) currently utilizes oral contrast solutions to tag the colonic fluid and possibly residual stool for differentiation from the colon wall and polyps. The enhanced image density of the tagged colonic materials causes a significant partial volume (PV) effect into the colon wall as well as the lumen space (filled with air or CO II). The PV effect on the colon wall can "bury" polyps of size as large as 5mm by increasing their image densities to a noticeable level, resulting in false negatives. It can also create false positives when PV effect goes into the lumen space. We have been modeling the PV effect for mixture-based image segmentation and developing text-based computer-aided detection of polyp (CADpolyp) by utilizing the PV mixture-based image segmentation. This work presents some preliminary results of developing and applying texture-based CADpolyp technique to low-dose CTC studies. A total of 114 studies of asymptomatic patients older than 50, who underwent CTC and then optical colonoscopy (OC) on the same day, were selected from a database, which was accumulated in the past decade and contains various bowel preparations and CT scanning protocols. The participating radiologists found ten polyps of greater than 5 mm from a total of 16 OC proved polyps, i.e., a detection sensitivity of 63%. They scored 23 false positives from the database, i.e., a 20% false positive rate. Approximately 70% of the datasets were marked as imperfect bowel cleansing and/or presence of image artifacts. The impact of imperfect bowel cleansing and image artifacts on VC performance is significant. The texture-based CADpolyp detected all the polyps with an average of 2.68 false positives per patient. This indicates that texture-based CADpolyp can improve the CTC performance in the cases of imperfect cleansed bowels and presence of image artifacts.

  15. Massive-training support vector regression and Gaussian process for false-positive reduction in computer-aided detection of polyps in CT colonography

    PubMed Central

    Xu, Jian-Wu; Suzuki, Kenji

    2011-01-01

    Purpose: A massive-training artificial neural network (MTANN) has been developed for the reduction of false positives (FPs) in computer-aided detection (CADe) of polyps in CT colonography (CTC). A major limitation of the MTANN is the long training time. To address this issue, the authors investigated the feasibility of two state-of-the-art regression models, namely, support vector regression (SVR) and Gaussian process regression (GPR) models, in the massive-training framework and developed massive-training SVR (MTSVR) and massive-training GPR (MTGPR) for the reduction of FPs in CADe of polyps. Methods: The authors applied SVR and GPR as volume-processing techniques in the distinction of polyps from FP detections in a CTC CADe scheme. Unlike artificial neural networks (ANNs), both SVR and GPR are memory-based methods that store a part of or the entire training data for testing. Therefore, their training is generally fast and they are able to improve the efficiency of the massive-training methodology. Rooted in a maximum margin property, SVR offers excellent generalization ability and robustness to outliers. On the other hand, GPR approaches nonlinear regression from a Bayesian perspective, which produces both the optimal estimated function and the covariance associated with the estimation. Therefore, both SVR and GPR, as the state-of-the-art nonlinear regression models, are able to offer a performance comparable or potentially superior to that of ANN, with highly efficient training. Both MTSVR and MTGPR were trained directly with voxel values from CTC images. A 3D scoring method based on a 3D Gaussian weighting function was applied to the outputs of MTSVR and MTGPR for distinction between polyps and nonpolyps. To test the performance of the proposed models, the authors compared them to the original MTANN in the distinction between actual polyps and various types of FPs in terms of training time reduction and FP reduction performance. The authors’ CTC database consisted of 240 CTC data sets obtained from 120 patients in the supine and prone positions. The training set consisted of 27 patients, 10 of which had 10 polyps. The authors selected 10 nonpolyps (i.e., FP sources) from the training set. These ten polyps and ten nonpolyps were used for training the proposed models. The testing set consisted of 93 patients, including 19 polyps in 7 patients and 86 negative patients with 474 FPs produced by an original CADe scheme. Results: With the MTSVR, the training time was reduced by a factor of 190, while a FP reduction performance [by-polyp sensitivity of 94.7% (18∕19) with 2.5 (230∕93) FPs∕patient] comparable to that of the original MTANN [the same sensitivity with 2.6 (244∕93) FPs∕patient] was achieved. The classification performance in terms of the area under the receiver-operating-characteristic curve value of the MTGPR (0.82) was statistically significantly higher than that of the original MTANN (0.77), with a two-sided p-value of 0.03. The MTGPR yielded a 94.7% (18∕19) by-polyp sensitivity at a FP rate of 2.5 (235∕93) per patient and reduced the training time by a factor of 1.3. Conclusions: Both MTSVR and MTGPR improve the efficiency of the training in the massive-training framework while maintaining a comparable performance. PMID:21626922

  16. Exploring the clinical potential of an automatic colonic polyp detection method based on the creation of energy maps.

    PubMed

    Fernández-Esparrach, Glòria; Bernal, Jorge; López-Cerón, Maria; Córdova, Henry; Sánchez-Montes, Cristina; Rodríguez de Miguel, Cristina; Sánchez, Francisco Javier

    2016-09-01

    Polyp miss-rate is a drawback of colonoscopy that increases significantly for small polyps. We explored the efficacy of an automatic computer-vision method for polyp detection. Our method relies on a model that defines polyp boundaries as valleys of image intensity. Valley information is integrated into energy maps that represent the likelihood of the presence of a polyp. In 24 videos containing polyps from routine colonoscopies, all polyps were detected in at least one frame. The mean of the maximum values on the energy map was higher for frames with polyps than without (P < 0.001). Performance improved in high quality frames (AUC = 0.79 [95 %CI 0.70 - 0.87] vs. 0.75 [95 %CI 0.66 - 0.83]). With 3.75 set as the maximum threshold value, sensitivity and specificity for the detection of polyps were 70.4 % (95 %CI 60.3 % - 80.8 %) and 72.4 % (95 %CI 61.6 % - 84.6 %), respectively. Energy maps performed well for colonic polyp detection, indicating their potential applicability in clinical practice. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Ultrasound virtual endoscopy: Polyp detection and reliability of measurement in an in vitro study with pig intestine specimens

    PubMed Central

    Liu, Jin-Ya; Chen, Li-Da; Cai, Hua-Song; Liang, Jin-Yu; Xu, Ming; Huang, Yang; Li, Wei; Feng, Shi-Ting; Xie, Xiao-Yan; Lu, Ming-De; Wang, Wei

    2016-01-01

    AIM: To present our initial experience regarding the feasibility of ultrasound virtual endoscopy (USVE) and its measurement reliability for polyp detection in an in vitro study using pig intestine specimens. METHODS: Six porcine intestine specimens containing 30 synthetic polyps underwent USVE, computed tomography colonography (CTC) and optical colonoscopy (OC) for polyp detection. The polyp measurement defined as the maximum polyp diameter on two-dimensional (2D) multiplanar reformatted (MPR) planes was obtained by USVE, and the absolute measurement error was analyzed using the direct measurement as the reference standard. RESULTS: USVE detected 29 (96.7%) of 30 polyps, remaining a 7-mm one missed. There was one false-positive finding. Twenty-six (89.7%) of 29 reconstructed images were clearly depicted, while 29 (96.7%) of 30 polyps were displayed on CTC with one false-negative finding. In OC, all the polyps were detected. The intraclass correlation coefficient was 0.876 (95%CI: 0.745-0.940) for measurements obtained with USVE. The pooled absolute measurement errors ± the standard deviations of the depicted polyps with actual sizes ≤ 5 mm, 6-9 mm, and ≥ 10 mm were 1.9 ± 0.8 mm, 0.9 ± 1.2 mm, and 1.0 ± 1.4 mm, respectively. CONCLUSION: USVE is reliable for polyp detection and measurement in in vitro study. PMID:27022217

  18. Electronic cleansing for CT colonography using spectral-driven iterative reconstruction

    NASA Astrophysics Data System (ADS)

    Nasirudin, Radin A.; Näppi, Janne J.; Hironaka, Toru; Tachibana, Rie; Yoshida, Hiroyuki

    2017-03-01

    Dual-energy computed tomography is used increasingly in CT colonography (CTC). The combination of computer-aided detection (CADe) and dual-energy CTC (DE-CTC) has high clinical value, because it can detect clinically significant colonic lesions automatically at higher accuracy than does conventional single-energy CTC. While CADe has demonstrated its ability to detect small polyps, its performance is highly dependent on several factors, including the quality of CTC images and electronic cleansing (EC) of the images. The presence of artifacts such as beam hardening and image noise in ultra-low-dose CTC can produce incorrectly cleansed colon images that severely degrade the detection performance of CTC for small polyps. Also, CADe methods are very dependent on the quality of input images and the information about different tissues in the colon. In this work, we developed a novel method to calculate EC images using spectral information from DE-CTC data. First, the ultra-low dose dual-energy projection data obtained from a CT scanner are decomposed into two materials, soft tissue and the orally administered fecal-tagging contrast agent, to detect the location and intensity of the contrast agent. Next, the images are iteratively reconstructed while gradually removing the presence of tagged materials from the images. Our preliminary qualitative results show that the method can cleanse the contrast agent and tagged materials correctly from DE-CTC images without affecting the appearance of surrounding tissue.

  19. Antral hyperplastic polyp: A rare cause of gastric outlet obstruction.

    PubMed

    Aydin, Ibrahim; Ozer, Ender; Rakici, Halil; Sehitoglu, Ibrahim; Yucel, Ahmet Fikret; Pergel, Ahmet; Sahin, Dursun Ali

    2014-01-01

    Gastric polyps are usually found incidentally during upper gastrointestinal endoscopic examinations. These polyps are generally benign, with hyperplasia being the most common. While gastric polyps are often asymptomatic, they can cause gastric outlet obstruction. A 64 years-old female patient presented to our polyclinic with a history of approximately 2 months of weakness, occasional early nausea, vomiting after meals and epigastric pain. A polypoid lesion of approximately 25mm in diameter was detected in the antral area of the stomach, which prolapsed through the pylorus into the duodenal bulbus, and subsequently caused gastric outlet obstruction, as revealed by upper gastrointestinal endoscopy of the patient. The polyp was retrieved from the pyloric canal into the stomach with the aid of a tripod, and snare polypectomy was performed. Currently, widespread use of endoscopy has led to an increase in the frequency of detecting hyperplastic polyps. While most gastric polyps are asymptomatic, they can cause iron deficiency anemia, acute pancreatitis and more commonly, gastric outlet obstruction because of their antral location. Although there are no precise principles in the treatment of asymptomatic polyps, polyps >5mm should be removed due to the possibility of malignant transformation. According to the medical evidence, polypectomy is required for gastric hyperplastic polyps because of the risks of complication and malignancy. These cases can be successfully treated endoscopically. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Antral hyperplastic polyp: A rare cause of gastric outlet obstruction

    PubMed Central

    Aydin, Ibrahim; Ozer, Ender; Rakici, Halil; Sehitoglu, Ibrahim; Yucel, Ahmet Fikret; Pergel, Ahmet; Sahin, Dursun Ali

    2014-01-01

    INTRODUCTION Gastric polyps are usually found incidentally during upper gastrointestinal endoscopic examinations. These polyps are generally benign, with hyperplasia being the most common. While gastric polyps are often asymptomatic, they can cause gastric outlet obstruction. PRESENTATION OF CASE A 64 years-old female patient presented to our polyclinic with a history of approximately 2 months of weakness, occasional early nausea, vomiting after meals and epigastric pain. A polypoid lesion of approximately 25 mm in diameter was detected in the antral area of the stomach, which prolapsed through the pylorus into the duodenal bulbus, and subsequently caused gastric outlet obstruction, as revealed by upper gastrointestinal endoscopy of the patient. The polyp was retrieved from the pyloric canal into the stomach with the aid of a tripod, and snare polypectomy was performed. DISCUSSION Currently, widespread use of endoscopy has led to an increase in the frequency of detecting hyperplastic polyps. While most gastric polyps are asymptomatic, they can cause iron deficiency anemia, acute pancreatitis and more commonly, gastric outlet obstruction because of their antral location. Although there are no precise principles in the treatment of asymptomatic polyps, polyps >5 mm should be removed due to the possibility of malignant transformation. CONCLUSION According to the medical evidence, polypectomy is required for gastric hyperplastic polyps because of the risks of complication and malignancy. These cases can be successfully treated endoscopically. PMID:24747755

  1. Contrast coating of the surface of flat polyps at CT colonography: a marker of detection

    PubMed Central

    Kim, David H.; Hinshaw, J. Louis; Lubner, Meghan G.; Munoz del Rio, Alejandro; Pooler, B. Dustin; Pickhardt, Perry J.

    2014-01-01

    Purpose To assess the frequency of oral contrast coating of flat polyps, which may promote detection, and influencing factors within a screening CTC population. Materials From 7,426 individuals, 123 patients with 160 flat polyps were extracted. Flat polyps were defined as plaque-like, raised ≤ 3mm in height and reviewed for contrast coating. Factors including demographic variables such as age and sex, and polyp variables such as polyp size, location, and histology were analyzed for effect on coating. Results Of 160 flat polyps (mean size 9.4mm±3.6), 78.8% demonstrated coating. Mean coat thickness was 1.5mm±0.6; 23.8% (n=30), demonstrating a thin film of contrast. Large size (≥10 mm), and proximal colonic location (relative to splenic flexure) were predictive variables by univariate logistic regression [OR (odds ratio) 3.4(CI 1.3–8.9; p=0.011), 2.0(CI 1.2–3.5; p=0.011), respectively]. Adenomas (OR 0.37, CI: 0.14–1.02; p=0.054) and mucosal polyps or venous blebs (OR 0.07, CI: 0.02–0.25; p < 0.001) were less likely to coat than serrated/hyperplastic lesions. Age and sex were not predictive for coating (p=0.417, p= 0.499, respectively). Conclusions Surface contrast coating is common for flat polyps at CTC, promoted by large size, proximal location, and serrated/hyperplastic histology. Given the difficulty in detection, recognition may aid in flat polyp identification. PMID:24482303

  2. Measurement of smaller colon polyp in CT colonography images using morphological image processing.

    PubMed

    Manjunath, K N; Siddalingaswamy, P C; Prabhu, G K

    2017-11-01

    Automated measurement of the size and shape of colon polyps is one of the challenges in Computed tomography colonography (CTC). The objective of this retrospective study was to improve the sensitivity and specificity of smaller polyp measurement in CTC using image processing techniques. A domain knowledge-based method has been implemented with hybrid method of colon segmentation, morphological image processing operators for detecting the colonic structures, and the decision-making system for delineating the smaller polyp-based on a priori knowledge. The method was applied on 45 CTC dataset. The key finding was that the smaller polyps were accurately measured. In addition to 6-9 mm range, polyps of even <5 mm were also detected. The results were validated qualitatively and quantitatively using both 2D MPR and 3D view. Implementation was done on a high-performance computer with parallel processing. It takes [Formula: see text] min for measuring the smaller polyp in a dataset of 500 CTC images. With this method, [Formula: see text] and [Formula: see text] were achieved. The domain-based approach with morphological image processing has given good results. The smaller polyps were measured accurately which helps in making right clinical decisions. Qualitatively and quantitatively the results were acceptable when compared to the ground truth at [Formula: see text].

  3. A ROC-based feature selection method for computer-aided detection and diagnosis

    NASA Astrophysics Data System (ADS)

    Wang, Songyuan; Zhang, Guopeng; Liao, Qimei; Zhang, Junying; Jiao, Chun; Lu, Hongbing

    2014-03-01

    Image-based computer-aided detection and diagnosis (CAD) has been a very active research topic aiming to assist physicians to detect lesions and distinguish them from benign to malignant. However, the datasets fed into a classifier usually suffer from small number of samples, as well as significantly less samples available in one class (have a disease) than the other, resulting in the classifier's suboptimal performance. How to identifying the most characterizing features of the observed data for lesion detection is critical to improve the sensitivity and minimize false positives of a CAD system. In this study, we propose a novel feature selection method mR-FAST that combines the minimal-redundancymaximal relevance (mRMR) framework with a selection metric FAST (feature assessment by sliding thresholds) based on the area under a ROC curve (AUC) generated on optimal simple linear discriminants. With three feature datasets extracted from CAD systems for colon polyps and bladder cancer, we show that the space of candidate features selected by mR-FAST is more characterizing for lesion detection with higher AUC, enabling to find a compact subset of superior features at low cost.

  4. Automated synthesis, insertion and detection of polyps for CT colonography

    NASA Astrophysics Data System (ADS)

    Sezille, Nicolas; Sadleir, Robert J. T.; Whelan, Paul F.

    2003-03-01

    CT Colonography (CTC) is a new non-invasive colon imaging technique which has the potential to replace conventional colonoscopy for colorectal cancer screening. A novel system which facilitates automated detection of colorectal polyps at CTC is introduced. As exhaustive testing of such a system using real patient data is not feasible, more complete testing is achieved through synthesis of artificial polyps and insertion into real datasets. The polyp insertion is semi-automatic: candidate points are manually selected using a custom GUI, suitable points are determined automatically from an analysis of the local neighborhood surrounding each of the candidate points. Local density and orientation information are used to generate polyps based on an elliptical model. Anomalies are identified from the modified dataset by analyzing the axial images. Detected anomalies are classified as potential polyps or natural features using 3D morphological techniques. The final results are flagged for review. The system was evaluated using 15 scenarios. The sensitivity of the system was found to be 65% with 34% false positive detections. Automated diagnosis at CTC is possible and thorough testing is facilitated by augmenting real patient data with computer generated polyps. Ultimately, automated diagnosis will enhance standard CTC and increase performance.

  5. A comparison of computer-assisted detection (CAD) programs for the identification of colorectal polyps: performance and sensitivity analysis, current limitations and practical tips for radiologists.

    PubMed

    Bell, L T O; Gandhi, S

    2018-06-01

    To directly compare the accuracy and speed of analysis of two commercially available computer-assisted detection (CAD) programs in detecting colorectal polyps. In this retrospective single-centre study, patients who had colorectal polyps identified on computed tomography colonography (CTC) and subsequent lower gastrointestinal endoscopy, were analysed using two commercially available CAD programs (CAD1 and CAD2). Results were compared against endoscopy to ascertain sensitivity and positive predictive value (PPV) for colorectal polyps. Time taken for CAD analysis was also calculated. CAD1 demonstrated a sensitivity of 89.8%, PPV of 17.6% and mean analysis time of 125.8 seconds. CAD2 demonstrated a sensitivity of 75.5%, PPV of 44.0% and mean analysis time of 84.6 seconds. The sensitivity and PPV for colorectal polyps and CAD analysis times can vary widely between current commercially available CAD programs. There is still room for improvement. Generally, there is a trade-off between sensitivity and PPV, and so further developments should aim to optimise both. Information on these factors should be made routinely available, so that an informed choice on their use can be made. This information could also potentially influence the radiologist's use of CAD results. Copyright © 2018 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  6. Virtually assisted optical colonoscopy

    NASA Astrophysics Data System (ADS)

    Marino, Joseph; Qiu, Feng; Kaufman, Arie

    2008-03-01

    We present a set of tools used to enhance the optical colonoscopy procedure in a novel manner with the aim of improving both the accuracy and efficiency of this procedure. In order to better present the colon information to the gastroenterologist performing a conventional (optical) colonoscopy, we undistort the radial distortion of the fisheye view of the colonoscope. The radial distortion is modeled with a function that converts the fisheye view to the perspective view, where the shape and size of polyps can be more readily observed. The conversion, accelerated on the graphics processing unit and running in real-time, calculates the corresponding position in the fisheye view of each pixel on the perspective image. We also merge our previous work in computer-aided polyp detection for virtual colonoscopy into the optical colonoscopy environment. The physical colonoscope path in the optical colonoscopy is approximated with the hugging corner shortest path, which is correlated with the centerline in the virtual colonoscopy. With the estimated distance that the colonoscope has been inserted, we are able to provide the gastroenterologist with visual cues along the observation path as to the location of possible polyps found by the detection process. In order to present the information to the gastroenterologist in a non-intrusive manner, we have developed a friendly user interface to enhance the optical colonoscopy without being cumbersome, distracting, or resulting in a more lackadaisical inspection by the gastroenterologist.

  7. Multi-detector row CT colonography: effect of collimation, pitch, and orientation on polyp detection in a human colectomy specimen.

    PubMed

    Taylor, Stuart A; Halligan, Steve; Bartram, Clive I; Morgan, Paul R; Talbot, Ian C; Fry, Nicola; Saunders, Brian P; Khosraviani, Kirosh; Atkin, Wendy

    2003-10-01

    To investigate the effects of orientation, collimation, pitch, and tube current setting on polyp detection at multi-detector row computed tomographic (CT) colonography and to determine the optimal combination of scanning parameters for screening. A colectomy specimen containing 117 polyps of different sizes was insufflated and imaged with a multi-detector row CT scanner at various collimation (1.25 and 2.5 mm), pitch (3 and 6), and tube current (50, 100, and 150 mA) settings. Two-dimensional multiplanar reformatted images and three-dimensional endoluminal surface renderings from the 12 resultant data sets were examined by one observer for the presence and conspicuity of polyps. The results were analyzed with Poisson regression and logistic regression to determine the effects of scanning parameters and of specimen orientation on polyp detection. The percentage of polyps that were detected significantly increased when collimation (P =.008) and table feed (P =.03) were decreased. Increased tube current resulted in improved detection only of polyps with a diameter of less than 5 mm. Polyps of less than 5 mm were optimally depicted with a collimation of 1.25 mm, a pitch of 3, and a tube current setting of 150 mA; polyps with a diameter greater than 5 mm were adequately depicted with 1.25-mm collimation and with either pitch setting and any of the three tube current settings. Small polyps in the transverse segment (positioned at a 90 degrees angle to the z axis of scanning) were significantly less visible than those in parallel or oblique orientations (P <.001). The effective radiation dose, calculated with a Monte Carlo simulation, was 1.4-10.0 mSv. Detection of small polyps (<5 mm) with multi-detector row CT is highly dependent on collimation, pitch, and, to a lesser extent, tube current. Collimation of 1.25 mm, combined with pitch of 6 and tube current of 50 mA, provides for reliable detection of polyps 5 mm or larger while limiting the effective radiation dose. Polyps smaller than 5 mm, however, may be poorly depicted with use of these settings in the transverse colon. Copyright RSNA, 2003

  8. Computed Tomography Colonography vs Colonoscopy for Colorectal Cancer Surveillance After Surgery.

    PubMed

    Weinberg, David S; Pickhardt, Perry J; Bruining, David H; Edwards, Kristin; Fletcher, Joel G; Gollub, Marc J; Keenan, Eileen M; Kupfer, Sonia S; Li, Tianyu; Lubner, Sam J; Markowitz, Arnold J; Ross, Eric A

    2018-03-01

    Recommendations for surveillance after curative surgery for colorectal cancer (CRC) include a 1-year post-resection abdominal-pelvic computed tomography (CT) scan and optical colonoscopy (OC). CT colonography (CTC), when used in CRC screening, effectively identifies colorectal polyps ≥10 mm and cancers. We performed a prospective study to determine whether CTC, concurrent with CT, could substitute for OC in CRC surveillance. Our study enrolled 231 patients with resected stage 0-III CRC, identified at 5 tertiary care academic centers. Approximately 1 year after surgery, participants underwent outpatient CTC plus CT, followed by same-day OC. CTC results were revealed after endoscopic visualization of sequential colonic segments, which were re-examined for discordant findings. The primary outcome was performance of CTC in the detection of colorectal adenomas and cancers using endoscopy as the reference standard. Of the 231 participants, 116 (50.2%) had polyps of any size or histology identified by OC, and 15.6% had conventional adenomas and/or serrated polyps ≥6 mm. No intra-luminal cancers were detected. CTC detected patients with polyps of ≥6 mm with 44.0% sensitivity (95% CI, 30.2-57.8) and 93.4% specificity (95% CI, 89.7-97.0). CTC detected polyps ≥10 mm with 76.9% sensitivity (95% CI, 54.0-99.8) and 89.0% specificity (95% CI, 84.8-93.1). Similar values were found when only adenomatous polyps were considered. The negative predictive value of CTC for adenomas ≥6 mm was 90.7% (95% CI, 86.7-94.5) and for adenomas ≥10 mm the negative predictive value was 98.6% (95% CI, 97.0-100). In a CRC surveillance population 1 year following resection, CTC was inferior to OC for detecting patients with polyps ≥6 mm. Clinical Trials.gov Registration Number: NCT02143115. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

  9. SVM based colon polyps classifier in a wireless active stereo endoscope.

    PubMed

    Ayoub, J; Granado, B; Mhanna, Y; Romain, O

    2010-01-01

    This work focuses on the recognition of three-dimensional colon polyps captured by an active stereo vision sensor. The detection algorithm consists of SVM classifier trained on robust feature descriptors. The study is related to Cyclope, this prototype sensor allows real time 3D object reconstruction and continues to be optimized technically to improve its classification task by differentiation between hyperplastic and adenomatous polyps. Experimental results were encouraging and show correct classification rate of approximately 97%. The work contains detailed statistics about the detection rate and the computing complexity. Inspired by intensity histogram, the work shows a new approach that extracts a set of features based on depth histogram and combines stereo measurement with SVM classifiers to correctly classify benign and malignant polyps.

  10. [Differential concentrations of conjugated bile acids in sera of patients with polypoid lesions of gallbladder].

    PubMed

    Huang, Peng; Zhao, Meifen; Meng, Fanbin; Sun, Tao; He, Chunxu; Chen, Jingyu; Zhang, Jiali; Huang, Jiapeng; Ge, Chunlin

    2014-11-04

    To explore the concentration differences of eight conjugated bile acids between patients of cholesterol polyps and adenomatous polyps and determine the differential diagnosis markers for polypoid lesions of gallbladder (PLG). During the period of March 2013 to November, 18 cholesterol polyps patients, 9 adenomatous polyps ones and 20 simple gallstone disease ones were enrolled. High performance liquid chromatography with ultraviolet detection was used to test 8 conjugated bile acids in sera. A total of 8 conjugated bile acids were completely dissociated within 10 minutes and the assay was liner in the range of 3.91 to 500.00 mg/L. The correlation coefficients for linear regression were from 0.995 to 0.999 and the detection limits ranged from 3.91 to 7.81 mg/L. The serum level of glycocholic acid (GCA) in adenomatous polyps group (3.48 ± 1.66) mg/L was significantly higher than that in cholesterol polyps group ((2.16 ± 0.71) mg/L, q = 5.182, P = 0.001) and control group ((2.15 ± 0.45) mg/L, q = 5.313, P = 0.001). The serum level of glycochenodeoxycholic acid (GCDCA) in adenomatous polyps group (12.67 ± 1.74) mg/L was significantly higher than that in cholesterol polyps group ((10.53 ± 3.04) mg/L, q = 3.253, P = 0.026) and control group ((10.72 ± 1.58) mg/L, q = 3.015, P = 0.038). The serum level of taurochenodeoxycholic acid (TCDCA) in adenomatous polyps group ((6.79 ± 2.90) mg/L) was significantly higher than that in cholesterol polyps group ((4.47 ± 2.35) mg/L, q = 3.412, P = 0.020) and control group ((4.72 ± 2.11) mg/L q = 3.091, P = 0.034). The serum levels of GCA, GCDCA and TCDCA in adenomatous polyps patients are higher than those in cholesterol polyps counterparts. And these markers may aid the differential diagnosis of PLG.

  11. A dimension reduction strategy for improving the efficiency of computer-aided detection for CT colonography

    NASA Astrophysics Data System (ADS)

    Song, Bowen; Zhang, Guopeng; Wang, Huafeng; Zhu, Wei; Liang, Zhengrong

    2013-02-01

    Various types of features, e.g., geometric features, texture features, projection features etc., have been introduced for polyp detection and differentiation tasks via computer aided detection and diagnosis (CAD) for computed tomography colonography (CTC). Although these features together cover more information of the data, some of them are statistically highly-related to others, which made the feature set redundant and burdened the computation task of CAD. In this paper, we proposed a new dimension reduction method which combines hierarchical clustering and principal component analysis (PCA) for false positives (FPs) reduction task. First, we group all the features based on their similarity using hierarchical clustering, and then PCA is employed within each group. Different numbers of principal components are selected from each group to form the final feature set. Support vector machine is used to perform the classification. The results show that when three principal components were chosen from each group we can achieve an area under the curve of receiver operating characteristics of 0.905, which is as high as the original dataset. Meanwhile, the computation time is reduced by 70% and the feature set size is reduce by 77%. It can be concluded that the proposed method captures the most important information of the feature set and the classification accuracy is not affected after the dimension reduction. The result is promising and further investigation, such as automatically threshold setting, are worthwhile and are under progress.

  12. An integrated classifier for computer-aided diagnosis of colorectal polyps based on random forest and location index strategies

    NASA Astrophysics Data System (ADS)

    Hu, Yifan; Han, Hao; Zhu, Wei; Li, Lihong; Pickhardt, Perry J.; Liang, Zhengrong

    2016-03-01

    Feature classification plays an important role in differentiation or computer-aided diagnosis (CADx) of suspicious lesions. As a widely used ensemble learning algorithm for classification, random forest (RF) has a distinguished performance for CADx. Our recent study has shown that the location index (LI), which is derived from the well-known kNN (k nearest neighbor) and wkNN (weighted k nearest neighbor) classifier [1], has also a distinguished role in the classification for CADx. Therefore, in this paper, based on the property that the LI will achieve a very high accuracy, we design an algorithm to integrate the LI into RF for improved or higher value of AUC (area under the curve of receiver operating characteristics -- ROC). Experiments were performed by the use of a database of 153 lesions (polyps), including 116 neoplastic lesions and 37 hyperplastic lesions, with comparison to the existing classifiers of RF and wkNN, respectively. A noticeable gain by the proposed integrated classifier was quantified by the AUC measure.

  13. Computer-assisted polyp matching between optical colonoscopy and CT colonography: a phantom study

    NASA Astrophysics Data System (ADS)

    Roth, Holger R.; Hampshire, Thomas E.; Helbren, Emma; Hu, Mingxing; Vega, Roser; Halligan, Steve; Hawkes, David J.

    2014-03-01

    Potentially precancerous polyps detected with CT colonography (CTC) need to be removed subsequently, using an optical colonoscope (OC). Due to large colonic deformations induced by the colonoscope, even very experienced colonoscopists find it difficult to pinpoint the exact location of the colonoscope tip in relation to polyps reported on CTC. This can cause unduly prolonged OC examinations that are stressful for the patient, colonoscopist and supporting staff. We developed a method, based on monocular 3D reconstruction from OC images, that automatically matches polyps observed in OC with polyps reported on prior CTC. A matching cost is computed, using rigid point-based registration between surface point clouds extracted from both modalities. A 3D printed and painted phantom of a 25 cm long transverse colon segment was used to validate the method on two medium sized polyps. Results indicate that the matching cost is smaller at the correct corresponding polyp between OC and CTC: the value is 3.9 times higher at the incorrect polyp, comparing the correct match between polyps to the incorrect match. Furthermore, we evaluate the matching of the reconstructed polyp from OC with other colonic endoluminal surface structures such as haustral folds and show that there is a minimum at the correct polyp from CTC. Automated matching between polyps observed at OC and prior CTC would facilitate the biopsy or removal of true-positive pathology or exclusion of false-positive CTC findings, and would reduce colonoscopy false-negative (missed) polyps. Ultimately, such a method might reduce healthcare costs, patient inconvenience and discomfort.

  14. Utility of contrast-enhanced harmonic EUS in the diagnosis of malignant gallbladder polyps (with videos).

    PubMed

    Choi, Jun-Ho; Seo, Dong-Wan; Choi, Joon Hyuk; Park, Do Hyun; Lee, Sang Soo; Lee, Sung Koo; Kim, Myung-Hwan

    2013-09-01

    The differential diagnosis between benign and malignant polyps of the gallbladder (GB) is often challenging. To evaluate whether contrast-enhanced harmonic EUS (CEH-EUS) might be an accurate method for discriminating malignant GB polyps from benign polyps. Observational study. Tertiary care medical center. Ninety-three patients with GB polyps larger than 10 mm in diameter that were detected by conventional EUS underwent CEH-EUS for evaluation of microvasculature. CEH-EUS was performed using a radial echoendoscope and the extended pure harmonic detection mode. The abilities of conventional EUS and CEH-EUS to diagnose malignant polyp were compared. Two blinded reviewers classified the perfusion images into 3 categories: diffuse enhancement, perfusion defect, or nonenhancement. The vessel images were categorized as having a regular spotty vessel, an irregular vessel, or no vessels. An irregular vessel pattern determined by CEH-EUS aided in the diagnosis of malignant polyps with a sensitivity and specificity of 90.3% and 96.6%, respectively. The presence of perfusion defects, determined by CEH-EUS, was calculated to diagnose malignant polyps with a sensitivity and specificity of 90.3% and 94.9%, respectively. Based on the definitely determined diagnosis, sensitivity and specificity for CEH-EUS were 93.5% and 93.2% versus 90.0% and 91.1% for conventional EUS. In 8 cases, management changed after CEH-EUS. A tertiary medical center with a limited number of patients. The presence of irregular intratumoral vessels or perfusion defects seen on CEH-EUS may be sensitive and accurate predictors of malignant GB polyps. CEH-EUS offers slightly improved diagnostic accuracy compared with EUS. Copyright © 2013 American Society for Gastrointestinal Endoscopy. All rights reserved.

  15. Deep Learning Localizes and Identifies Polyps in Real Time with 96% Accuracy in Screening Colonoscopy.

    PubMed

    Urban, Gregor; Tripathi, Priyam; Alkayali, Talal; Mittal, Mohit; Jalali, Farid; Karnes, William; Baldi, Pierre

    2018-06-18

    The benefit of colonoscopy for colorectal cancer prevention depends on the adenoma detection rate (ADR). The ADR should reflect adenoma prevalence rate, estimated to be greater than 50% among the screening-age population. Yet the rate of adenoma detection by colonoscopists varies from 7% to 53%. It is estimated that every 1% increase in ADR reduces the risk of interval colorectal cancers by 3-6%. New strategies are needed to increase the ADR during colonoscopy. We tested the ability of computer-assisted image analysis, with convolutional neural networks (a deep learning model for image analysis), to improve polyp detection, a surrogate of ADR. We designed and trained deep convolutional neural networks (CNN) to detect polyps using a diverse and representative set of 8641 hand labeled images from screening colonoscopies collected from over 2000 patients. We tested the models on 20 colonoscopy videos with a total duration of 5 hours. Expert colonoscopists were asked to identify all polyps in 9 de-identified colonoscopy videos, selected from archived video studies, either with or without benefit of the CNN overlay. Their findings were compared with those of the CNN, using CNN-assisted expert review as the reference. When tested on manually labeled images, the CNN identified polyps with an area under the receiver operating characteristic curve (ROC-AUC) of 0.991 and an accuracy of 96.4%. In the analysis of colonoscopy videos in which 28 polyps were removed, 4 expert reviewers identified 8 additional polyps without CNN assistance that had not been removed and identified an additional 17 polyps with CNN assistance (45 in total). All polyps removed and identified by expert review were detected by the CNN. The CNN had a false-positive rate of 7%. In a set of 8641 colonoscopy images containing 4088 unique polyps the CNN identified polyps with a cross-validation accuracy of 96.4% and ROC-AUC value of 0.991. The CNN system can detect and localize polyps well within real-time constraints using an ordinary desktop machine with a contemporary graphics processing unit. This system could increase ADR and reduce interval colorectal cancers but requires validation in large multicenter trials. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

  16. Computer-Aided Diagnosis Based on Convolutional Neural Network System for Colorectal Polyp Classification: Preliminary Experience.

    PubMed

    Komeda, Yoriaki; Handa, Hisashi; Watanabe, Tomohiro; Nomura, Takanobu; Kitahashi, Misaki; Sakurai, Toshiharu; Okamoto, Ayana; Minami, Tomohiro; Kono, Masashi; Arizumi, Tadaaki; Takenaka, Mamoru; Hagiwara, Satoru; Matsui, Shigenaga; Nishida, Naoshi; Kashida, Hiroshi; Kudo, Masatoshi

    2017-01-01

    Computer-aided diagnosis (CAD) is becoming a next-generation tool for the diagnosis of human disease. CAD for colon polyps has been suggested as a particularly useful tool for trainee colonoscopists, as the use of a CAD system avoids the complications associated with endoscopic resections. In addition to conventional CAD, a convolutional neural network (CNN) system utilizing artificial intelligence (AI) has been developing rapidly over the past 5 years. We attempted to generate a unique CNN-CAD system with an AI function that studied endoscopic images extracted from movies obtained with colonoscopes used in routine examinations. Here, we report our preliminary results of this novel CNN-CAD system for the diagnosis of colon polyps. A total of 1,200 images from cases of colonoscopy performed between January 2010 and December 2016 at Kindai University Hospital were used. These images were extracted from the video of actual endoscopic examinations. Additional video images from 10 cases of unlearned processes were retrospectively assessed in a pilot study. They were simply diagnosed as either an adenomatous or nonadenomatous polyp. The number of images used by AI to learn to distinguish adenomatous from nonadenomatous was 1,200:600. These images were extracted from the videos of actual endoscopic examinations. The size of each image was adjusted to 256 × 256 pixels. A 10-hold cross-validation was carried out. The accuracy of the 10-hold cross-validation is 0.751, where the accuracy is the ratio of the number of correct answers over the number of all the answers produced by the CNN. The decisions by the CNN were correct in 7 of 10 cases. A CNN-CAD system using routine colonoscopy might be useful for the rapid diagnosis of colorectal polyp classification. Further prospective studies in an in vivo setting are required to confirm the effectiveness of a CNN-CAD system in routine colonoscopy. © 2017 S. Karger AG, Basel.

  17. CT colonography: automated measurement of colonic polyps compared with manual techniques--human in vitro study.

    PubMed

    Taylor, Stuart A; Slater, Andrew; Halligan, Steve; Honeyfield, Lesley; Roddie, Mary E; Demeshski, Jamshid; Amin, Hamdam; Burling, David

    2007-01-01

    To prospectively investigate the relative accuracy and reproducibility of manual and automated computer software measurements by using polyps of known size in a human colectomy specimen. Institutional review board approval was obtained for the study; written consent for use of the surgical specimen was obtained. A colectomy specimen containing 27 polyps from a 16-year-old male patient with familial adenomatous polyposis was insufflated, submerged in a container with solution, and scanned at four-section multi-detector row computed tomography (CT). A histopathologist measured the maximum dimension of all polyps in the opened specimen. Digital photographs and line drawings were produced to aid CT-histologic measurement correlation. A novice (radiographic technician) and an experienced (radiologist) observer independently estimated polyp diameter with three methods: manual two-dimensional (2D) and manual three-dimensional (3D) measurement with software calipers and automated measurement with software (automatic). Data were analyzed with paired t tests and Bland-Altman limits of agreement. Seven polyps (

  18. Pre-operative predictive factors for gallbladder cholesterol polyps using conventional diagnostic imaging

    PubMed Central

    Choi, Ji-Hoon; Yun, Jung-Won; Kim, Yong-Sung; Lee, Eun-A; Hwang, Sang-Tae; Cho, Yong-Kyun; Kim, Hong-Joo; Park, Jung-Ho; Park, Dong-Il; Sohn, Chong-Il; Jeon, Woo-Kyu; Kim, Byung-Ik; Kim, Hyoung-Ook; Shin, Jun-Ho

    2008-01-01

    AIM: To determine the clinical data that might be useful for differentiating benign from malignant gallbladder (GB) polyps by comparing radiological methods, including abdominal ultrasonography (US) and computed tomography (CT) scanning, with postoperative pathology findings. METHODS: Fifty-nine patients underwent laparoscopic cholecystectomy for a GB polyp of around 10 mm. They were divided into two groups, one with cholesterol polyps and the other with non-cholesterol polyps. Clinical features such as gender, age, symptoms, size and number of polyps, the presence of a GB stone, the radiologically measured maximum diameter of the polyp by US and CT scanning, and the measurements of diameter from postoperative pathology were recorded for comparative analysis. RESULTS: Fifteen of the 41 cases with cholesterol polyps (36.6%) were detected with US but not CT scanning, whereas all 18 non-cholesterol polyps were observed using both methods. In the cholesterol polyp group, the maximum measured diameter of the polyp was smaller by CT scan than by US. Consequently, the discrepancy between those two scanning measurements was greater than for the non-cholesterol polyp group. CONCLUSION: The clinical signs indicative of a cholesterol polyp include: (1) a polyp observed by US but not observable by CT scanning, (2) a smaller diameter on the CT scan compared to US, and (3) a discrepancy in its maximum diameter between US and CT measurements. In addition, US and the CT scan had low accuracy in predicting the polyp diameter compared to that determined by postoperative pathology. PMID:19058309

  19. Pre-operative predictive factors for gallbladder cholesterol polyps using conventional diagnostic imaging.

    PubMed

    Choi, Ji-Hoon; Yun, Jung-Won; Kim, Yong-Sung; Lee, Eun-A; Hwang, Sang-Tae; Cho, Yong-Kyun; Kim, Hong-Joo; Park, Jung-Ho; Park, Dong-Il; Sohn, Chong-Il; Jeon, Woo-Kyu; Kim, Byung-Ik; Kim, Hyoung-Ook; Shin, Jun-Ho

    2008-11-28

    To determine the clinical data that might be useful for differentiating benign from malignant gallbladder (GB) polyps by comparing radiological methods, including abdominal ultrasonography (US) and computed tomography (CT) scanning, with postoperative pathology findings. Fifty-nine patients underwent laparoscopic cholecystectomy for a GB polyp of around 10 mm. They were divided into two groups, one with cholesterol polyps and the other with non-cholesterol polyps. Clinical features such as gender, age, symptoms, size and number of polyps, the presence of a GB stone, the radiologically measured maximum diameter of the polyp by US and CT scanning, and the measurements of diameter from postoperative pathology were recorded for comparative analysis. Fifteen of the 41 cases with cholesterol polyps (36.6%) were detected with US but not CT scanning, whereas all 18 non-cholesterol polyps were observed using both methods. In the cholesterol polyp group, the maximum measured diameter of the polyp was smaller by CT scan than by US. Consequently, the discrepancy between those two scanning measurements was greater than for the non-cholesterol polyp group. The clinical signs indicative of a cholesterol polyp include: (1) a polyp observed by US but not observable by CT scanning, (2) a smaller diameter on the CT scan compared to US, and (3) a discrepancy in its maximum diameter between US and CT measurements. In addition, US and the CT scan had low accuracy in predicting the polyp diameter compared to that determined by postoperative pathology.

  20. Two methods of Haustral fold detection from computed tomographic virtual colonoscopy images

    NASA Astrophysics Data System (ADS)

    Chowdhury, Ananda S.; Tan, Sovira; Yao, Jianhua; Linguraru, Marius G.; Summers, Ronald M.

    2009-02-01

    Virtual colonoscopy (VC) has gained popularity as a new colon diagnostic method over the last decade. VC is a new, less invasive alternative to the usually practiced optical colonoscopy for colorectal polyp and cancer screening, the second major cause of cancer related deaths in industrial nations. Haustral (colonic) folds serve as important landmarks for virtual endoscopic navigation in the existing computer-aided-diagnosis (CAD) system. In this paper, we propose and compare two different methods of haustral fold detection from volumetric computed tomographic virtual colonoscopy images. The colon lumen is segmented from the input using modified region growing and fuzzy connectedness. The first method for fold detection uses a level set that evolves on a mesh representation of the colon surface. The colon surface is obtained from the segmented colon lumen using the Marching Cubes algorithm. The second method for fold detection, based on a combination of heat diffusion and fuzzy c-means algorithm, is employed on the segmented colon volume. Folds obtained on the colon volume using this method are then transferred to the corresponding colon surface. After experimentation with different datasets, results are found to be promising. The results also demonstrate that the first method has a tendency of slight under-segmentation while the second method tends to slightly over-segment the folds.

  1. Display modes for CT colonography. Part II. Blinded comparison of axial CT and virtual endoscopic and panoramic endoscopic volume-rendered studies.

    PubMed

    Beaulieu, C F; Jeffrey, R B; Karadi, C; Paik, D S; Napel, S

    1999-07-01

    To determine the sensitivity of radiologist observers for detecting colonic polyps by using three different data review (display) modes for computed tomographic (CT) colonography, or "virtual colonoscopy." CT colonographic data in a patient with a normal colon were used as base data for insertion of digitally synthesized polyps. Forty such polyps (3.5, 5, 7, and 10 mm in diameter) were randomly inserted in four copies of the base data. Axial CT studies, volume-rendered virtual endoscopic movies, and studies from a three-dimensional mode termed "panoramic endoscopy" were reviewed blindly and independently by two radiologists. Detection improved with increasing polyp size. Trends in sensitivity were dependent on whether all inserted lesions or only visible lesions were considered, because modes differed in how completely the colonic surface was depicted. For both reviewers and all polyps 7 mm or larger, panoramic endoscopy resulted in significantly greater sensitivity (90%) than did virtual endoscopy (68%, P = .014). For visible lesions only, the sensitivities were 85%, 81%, and 60% for one reader and 65%, 62%, and 28% for the other for virtual endoscopy, panoramic endoscopy, and axial CT, respectively. Three-dimensional displays were more sensitive than two-dimensional displays (P < .05). The sensitivity of panoramic endoscopy is higher than that of virtual endoscopy, because the former displays more of the colonic surface. Higher sensitivities for three-dimensional displays may justify the additional computation and review time.

  2. In vivo endoscopic Doppler optical coherence tomography imaging of mouse colon

    NASA Astrophysics Data System (ADS)

    Welge, Weston A.; Barton, Jennifer K.

    2016-03-01

    Colorectal cancer remains the second deadliest cancer in the United States, despite the high sensitivity and specificity of colonoscopy and sigmoidoscopy. While these standard imaging procedures can accurately detect medium and large polyps, some studies have shown miss rates up to 25% for polyps less than 5 mm in diameter. An imaging modality capable of detecting small lesions could potentially improve patient outcomes. Optical coherence tomography (OCT) has been shown to be a powerful imaging modality for adenoma detection in a mouse model of colorectal cancer. While previous work has focused on analyzing the structural OCT images based on thickening of the mucosa and changes in light attenuation in depth, imaging the microvasculature of the colon may enable earlier detection of polyps. The structure and function of vessels grown to support tumor growth are markedly different from healthy vessels. Doppler OCT is capable of imaging microvessels in vivo. We developed a method of processing raw fringe data from a commercial swept-source OCT system using a lab-built miniature endoscope to extract microvessels. This method can be used to measure vessel count and density and to measure flow velocities. This may improve early detection and aid in the development of new chemopreventive and chemotherapeutic drugs. We present, to the best of our knowledge, the first endoscopic Doppler OCT images of in vivo mouse colon.

  3. Long-term follow up of gallbladder polyps.

    PubMed

    Park, Jeong Youp; Hong, Sung Pil; Kim, Yoon Jae; Kim, Hong Jeoung; Kim, Hee Man; Cho, Jae Hee; Park, Seung Woo; Song, Si Young; Chung, Jae Bock; Bang, Seungmin

    2009-02-01

    The management of gallbladder polyps (GBP) is directly linked to the early diagnosis of gallbladder cancer (GBC). This study aimed to evaluate the malignant risk of GBP. In total, 1558 patients diagnosed with GBP were followed. Neoplastic polyps were defined as GBC and its premalignant lesions. The risk for malignancy was estimated with the cumulative detection rate of neoplastic polyps. Thirty-three cases (2.1%) were diagnosed with neoplastic polyps. The cumulative detection rates of neoplastic polyps were 1.7% at 1 year, 2.8% at 5 years, and 4% at 8 years after diagnosis. The size of GBP and the presence of gallstones were risk factors for neoplastic polyps. Polyps > or = 10 mm had a 24.2 times greater risk of malignancy than polyps < 10 mm. However, 15 of 33 neoplastic polyps (45.5%) were < 10 mm at the time of diagnosis of GBP. During follow up in 36 (3.5%) of 1027 cases, an increase in size was detected; of these, nine (25%) had neoplastic polyps. Even small polyps have a risk of malignancy, and careful long-term follow up of GBP will help detect and treat early GBC.

  4. A novel balloon colonoscope detects significantly more simulated polyps than a standard colonoscope in a colon model.

    PubMed

    Hasan, Nazia; Gross, Seth A; Gralnek, Ian M; Pochapin, Mark; Kiesslich, Ralf; Halpern, Zamir

    2014-12-01

    Although standard colonoscopy is considered the optimal test to detect adenomas, it can have a significant adenoma miss rate. A major contributing factor to high miss rates is the inability to visualize adenomas behind haustral folds and at anatomic flexures. To compare the diagnostic yield of balloon-assisted colonoscopy versus standard colonoscopy in the detection of simulated polyps in a colon model. Prospective, cohort study. International gastroenterology meeting. A colon model composed of elastic material, which mimics the flexible structure of haustral folds, allowing for dynamic responses to balloon inflation, with embedded simulated colon polyps (n = 12 silicone "polyps"). Fifty gastroenterologists were recruited to identify simulated colon polyps in a colon model, first using standard colonoscopy immediately followed by balloon-assisted colonoscopy. Detection of simulated polyps. The median polyp detection rate for all simulated polyps was significantly higher with balloon-assisted as compared with standard colonoscopy (91.7% vs 45.8%, respectively; P < .0001). The significantly higher simulated polyp detection rate with balloon-assisted versus standard colonoscopy was notable both for non-obscured polyps (100.0% vs 75.0%; P < .0001) and obscured polyps (88.0% vs 25.0%; P < .0001). Non-randomized design, use of a colon model, and simulated colon polyps. As compared with standard colonoscopy, balloon-assisted colonoscopy detected significantly more obscured and non-obscured simulated polyps in a colon model. Clinical studies in human participants are being pursued to further evaluate this new colonoscopic technology. Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  5. Seeing is believing: video classification for computed tomographic colonography using multiple-instance learning.

    PubMed

    Wang, Shijun; McKenna, Matthew T; Nguyen, Tan B; Burns, Joseph E; Petrick, Nicholas; Sahiner, Berkman; Summers, Ronald M

    2012-05-01

    In this paper, we present development and testing results for a novel colonic polyp classification method for use as part of a computed tomographic colonography (CTC) computer-aided detection (CAD) system. Inspired by the interpretative methodology of radiologists using 3-D fly-through mode in CTC reading, we have developed an algorithm which utilizes sequences of images (referred to here as videos) for classification of CAD marks. For each CAD mark, we created a video composed of a series of intraluminal, volume-rendered images visualizing the detection from multiple viewpoints. We then framed the video classification question as a multiple-instance learning (MIL) problem. Since a positive (negative) bag may contain negative (positive) instances, which in our case depends on the viewing angles and camera distance to the target, we developed a novel MIL paradigm to accommodate this class of problems. We solved the new MIL problem by maximizing a L2-norm soft margin using semidefinite programming, which can optimize relevant parameters automatically. We tested our method by analyzing a CTC data set obtained from 50 patients from three medical centers. Our proposed method showed significantly better performance compared with several traditional MIL methods.

  6. Seeing is Believing: Video Classification for Computed Tomographic Colonography Using Multiple-Instance Learning

    PubMed Central

    Wang, Shijun; McKenna, Matthew T.; Nguyen, Tan B.; Burns, Joseph E.; Petrick, Nicholas; Sahiner, Berkman

    2012-01-01

    In this paper we present development and testing results for a novel colonic polyp classification method for use as part of a computed tomographic colonography (CTC) computer-aided detection (CAD) system. Inspired by the interpretative methodology of radiologists using 3D fly-through mode in CTC reading, we have developed an algorithm which utilizes sequences of images (referred to here as videos) for classification of CAD marks. For each CAD mark, we created a video composed of a series of intraluminal, volume-rendered images visualizing the detection from multiple viewpoints. We then framed the video classification question as a multiple-instance learning (MIL) problem. Since a positive (negative) bag may contain negative (positive) instances, which in our case depends on the viewing angles and camera distance to the target, we developed a novel MIL paradigm to accommodate this class of problems. We solved the new MIL problem by maximizing a L2-norm soft margin using semidefinite programming, which can optimize relevant parameters automatically. We tested our method by analyzing a CTC data set obtained from 50 patients from three medical centers. Our proposed method showed significantly better performance compared with several traditional MIL methods. PMID:22552333

  7. Serrated and adenomatous polyp detection increases with longer withdrawal time: results from the New Hampshire Colonoscopy Registry.

    PubMed

    Butterly, Lynn; Robinson, Christina M; Anderson, Joseph C; Weiss, Julia E; Goodrich, Martha; Onega, Tracy L; Amos, Christopher I; Beach, Michael L

    2014-03-01

    Detection and removal of adenomas and clinically significant serrated polyps (CSSPs) is critical to the effectiveness of colonoscopy in preventing colorectal cancer. Although longer withdrawal time has been found to increase polyp detection, this association and the use of withdrawal time as a quality indicator remains controversial. Few studies have reported on withdrawal time and serrated polyp detection. Using data from the New Hampshire Colonoscopy Registry, we examined how an endoscopist's withdrawal time in normal colonoscopies affects adenoma and serrated polyp detection. We analyzed 7,996 colonoscopies performed in 7,972 patients between 2009 and 2011 by 42 endoscopists at 14 hospitals, ambulatory surgery centers, and community practices. CSSPs were defined as sessile serrated polyps and hyperplastic polyps proximal to the sigmoid. Adenoma and CSSP detection rates were calculated based on median endoscopist withdrawal time in normal exams. Regression models were used to estimate the association of increased normal withdrawal time and polyp, adenoma, and CSSP detection. Polyp and adenoma detection rates were highest among endoscopists with 9 min median normal withdrawal time, and detection of CSSPs reached its highest levels at 8-9 min. Incident rate ratios for adenoma and CSSP detection increased with each minute of normal withdrawal time above 6 min, with maximum benefit at 9 min for adenomas (1.50, 95% confidence interval (CI) (1.21, 1.85)) and CSSPs (1.77, 95% CI (1.15, 2.72)). When modeling was used to set the minimum withdrawal time at 9 min, we predicted that adenomas and CSSPs would be detected in 302 (3.8%) and 191 (2.4%) more patients. The increase in detection was most striking for the CSSPs, with nearly a 30% relative increase. A withdrawal time of 9 min resulted in a statistically significant increase in adenoma and serrated polyp detection. Colonoscopy quality may improve with a median normal withdrawal time benchmark of 9 min.

  8. [The comparison of the expansion of polyps according to the Ki-67 and computed tomography scores].

    PubMed

    Aydin, Sedat; Sanli, Arif; Tezer, Ilter; Hardal, Umit; Barişik, Nagehan Ozdemir

    2009-01-01

    The disease extention in nasal polyps was compared by using the mitotic activity rates and the computed tomography scores. This study was conducted on 19 nasal polyposis patients (8 males, 11 females; mean age 40.0+/-13.7 years; range 20 to 63 years). The preoperative computed tomography records of the patients were evaluated according to the Lund-Mackay grading system. The polyp tissues of the same patients were stained with the Ki-67 antigen for immunohistochemical evaluation. The correlation between the radiologic results and the Ki-67 values was compared by means of the Spearman's correlation test. The mean computed tomography score was observed as 14.3+/-4.7 (range 7-24). The mean Ki-67 score resulting from the immunohistochemical staining was calculated as 24.3+/-18.5 (range 3.3-73.5%). A significant correlation was determined between the Ki-67 values and the computed tomography scores. ("Spearman's" correlation factor: 0.677; p<0.001). As the mitotic activity rate of nasal polyps increases, both the volume of the polyps and the computed tomography scores increase as a result of the blockage of the sinus ostiums by the increased polyp volume.

  9. CT colonography of colorectal polyps: a metaanalysis.

    PubMed

    Sosna, Jacob; Morrin, Martina M; Kruskal, Jonathan B; Lavin, Philip T; Rosen, Max P; Raptopoulos, Vassilios

    2003-12-01

    For proper evaluation of the accuracy of CT colonography, prospective multiinstitutional trials would be ideal. Until these trials are available, data can be collectively analyzed. The purpose of this study is to use metaanalysis to assess the reported accuracy of CT colonography compared with conventional colonoscopy for detecting colorectal polyps. Articles comparing CT colonography and conventional colonoscopy were identified, and a standardized form was used to extract relevant study data. Fisher's exact test and the Mantel-Haenszel test were used for pooling of data. A 95% confidence interval (CI) was selected to determine sensitivity and specificity, and the Kruskal-Wallis exact test was used to identify trends relating to polyp size. Meta-analysis methods were used to test strength of results. Comparisons were made for the percentage of polyps detected grouped by size (> or = 10 mm, 6-9 mm, < or = 5 mm) and the percentage of patients identified who had polyps of the same size. Fourteen studies fulfilled all the study inclusion criteria and gave a total of 1,324 patients and 1,411 polyps. The pooled per-patient sensitivity for polyps 10 mm or larger was (sensitivity [95% CI]) 0.88 (0.84-0.93), for polyps 6-9 mm it was 0.84 (0.80-0.89), and for polyps 5 mm or smaller it was 0.65 (0.57-0.73). The pooled per-polyp sensitivity for polyps 10 mm or larger was 0.81 (0.76-0.85), for polyps 6-9 mm it was 0.62 (0.58-0.67), and for polyps 5 mm or smaller it was 0.43 (0.39-0.47). Sensitivity for detection of polyps increased as the polyp size increased (p < 0.00005). The pooled overall specificity for detection of polyps larger than 10 mm was 0.95 (0.94-0.97). The specificity and sensitivity of CT colonography are high for polyps larger than 10 mm.

  10. Incidentally detected gallbladder polyps: is follow-up necessary?--Long-term clinical and US analysis of 346 patients.

    PubMed

    Corwin, Michael T; Siewert, Bettina; Sheiman, Robert G; Kane, Robert A

    2011-01-01

    To determine the natural history of gallbladder (GB) polyps incidentally detected at ultrasonography (US) and to propose management guidelines for these lesions based on polyp size. The HIPAA-compliant study was approved by the institutional review board, and informed consent was waived. A database search for "polyp" in all US examinations of the GB between January 1, 1999, and December 31, 2001, at a single institution was performed. All subsequent US reports were reviewed to determine changes in GB polyp size. The electronic medical record was searched to obtain clinical and pathologic follow-up. Three hundred forty-six patients (mean age, 51.6 years; range, 20-93 years) with GB polyps were included. There were 156 men (45%) and 190 women (55%). US follow-up (mean, 5.4 years; range, 2-11.5 years) was performed in 149 patients (43%). Polyp size was stable in 90 (60%) polyps, decreased in eight (5%), increased in one (1%), and resolved in 50 (34%). Forty-two patients (12%) underwent cholecystectomy, revealing 13 (31%) GBs with polypoid lesions, 24 (57%) with stones and no polyps, and five (12%) with neither a stone nor a polypoid lesion. Clinical follow-up (mean, 8 years; range, 5-10.4 years) was performed in 155 patients (45%). No patient had clinical evidence of GB-related disease. Overall, no cases of GB malignancy were identified in 346 patients. Mean polyp size was 5.0 mm (range, 1-18 mm). No neoplastic polyps were found at 1-6 mm, one neoplastic polyp was seen at 7-9 mm, and two neoplastic polyps were found at 10 mm or larger. The risk of GB malignancy resulting from incidentally detected polyps is extremely low. Incidentally detected GB polyps measuring 6 mm or less may require no additional follow-up. Data are inconclusive regarding polyps 7 mm or greater, and further studies are warranted. © RSNA, 2010

  11. Differentiation of nonneoplastic and neoplastic gallbladder polyps 1 cm or bigger with multi-detector row computed tomography.

    PubMed

    Park, Ko Woon; Kim, Seong Hyun; Choi, Seong Ho; Lee, Won Jae

    2010-01-01

    To evaluate useful computed tomographic features to differentiate nonneoplastic and neoplastic gallbladder polyps 1 cm or bigger. Thirty-one patients with 32 nonneoplastic polyps and 67 patients with 73 neoplastic polyps 1 cm or bigger underwent unenhanced and dual-phase (arterial and portal venous phases) multi-detector row computed tomography. Gallbladder polyps were diagnosed by cholecystectomy. Computed tomographic features including size (1.5 cm), surface (smooth or irregular), shape (pedunculated or sessile), accompanying wall thickening, basal indentation, perception on unenhanced images, and enhancement pattern between 2 groups were compared using univariate and multivariate analyses. On univariate analysis, age 55 years or older (P = 0.0019), size bigger than 1.5 cm (P < 0.0001), irregular surface (P = 0.0033), sessile shape (P = 0.0016), accompanying wall thickening (P = 0.0056), basal indentation (P = 0.0236), and perception on unenhanced images (P < 0.0001) were significantly more frequent in neoplastic polyps as compared with nonneoplastic polyps. On multivariate analysis, size bigger than 1.5 cm (P = 0.0260), sessile shape (P = 0.0397), and perception on unenhanced images (P < 0.0001) were statistically significant. Size bigger than 1.5 cm, sessile shape, and perception on unenhanced images are the main factors that differentiate neoplastic from nonneoplastic gallbladder polyps 1 cm or bigger.

  12. Computer-aided teniae coli detection using height maps from computed tomographic colonography images

    NASA Astrophysics Data System (ADS)

    Wei, Zhuoshi; Yao, Jianhua; Wang, Shijun; Summers, Ronald M.

    2011-03-01

    Computed tomographic colonography (CTC) is a minimally invasive technique for colonic polyps and cancer screening. Teniae coli are three bands of longitudinal smooth muscle on the colon surface. They are parallel, equally distributed on the colon wall, and form a triple helix structure from the appendix to the sigmoid colon. Because of their characteristics, teniae coli are important anatomical meaningful landmarks on human colon. This paper proposes a novel method for teniae coli detection on CT colonography. We first unfold the three-dimensional (3D) colon using a reversible projection technique and compute the two-dimensional (2D) height map of the unfolded colon. The height map records the elevation of colon surface relative to the unfolding plane, where haustral folds corresponding to high elevation points and teniae to low elevation points. The teniae coli are detected on the height map and then projected back to the 3D colon. Since teniae are located where the haustral folds meet, we break down the problem by first detecting haustral folds. We apply 2D Gabor filter banks to extract fold features. The maximum response of the filter banks is then selected as the feature image. The fold centers are then identified based on piecewise thresholding on the feature image. Connecting the fold centers yields a path of the folds. Teniae coli are finally extracted as lines running between the fold paths. Experiments were carried out on 7 cases. The proposed method yielded a promising result with an average normalized RMSE of 5.66% and standard deviation of 4.79% of the circumference of the colon.

  13. Simple colonoscopy reporting system checking the detection rate of colon polyps.

    PubMed

    Kim, Jae Hyun; Choi, Youn Jung; Kwon, Hye Jung; Park, Seun Ja; Park, Moo In; Moon, Won; Kim, Sung Eun

    2015-08-21

    To present a simple colonoscopy reporting system that can be checked easily the detection rate of colon polyps. A simple colonoscopy reporting system Kosin Gastroenterology (KG quality reporting system) was developed. The polyp detection rate (PDR), adenoma detection rate (ADR), serrated polyp detection rate (SDR), and advanced adenoma detection rate (AADR) are easily calculated to use this system. In our gastroenterology center, the PDR, ADR, SDR, and AADR test results from each gastroenterologist were updated, every month. Between June 2014, when the program was started, and December 2014, the overall PDR and ADR in our center were 62.5% and 41.4%, respectively. And the overall SDR and AADR were 7.5% and 12.1%, respectively. We envision that KG quality reporting system can be applied to develop a comprehensive system to check colon polyp detection rates in other gastroenterology centers.

  14. Automatic colonic lesion detection and tracking in endoscopic videos

    NASA Astrophysics Data System (ADS)

    Li, Wenjing; Gustafsson, Ulf; A-Rahim, Yoursif

    2011-03-01

    The biology of colorectal cancer offers an opportunity for both early detection and prevention. Compared with other imaging modalities, optical colonoscopy is the procedure of choice for simultaneous detection and removal of colonic polyps. Computer assisted screening makes it possible to assist physicians and potentially improve the accuracy of the diagnostic decision during the exam. This paper presents an unsupervised method to detect and track colonic lesions in endoscopic videos. The aim of the lesion screening and tracking is to facilitate detection of polyps and abnormal mucosa in real time as the physician is performing the procedure. For colonic lesion detection, the conventional marker controlled watershed based segmentation is used to segment the colonic lesions, followed by an adaptive ellipse fitting strategy to further validate the shape. For colonic lesion tracking, a mean shift tracker with background modeling is used to track the target region from the detection phase. The approach has been tested on colonoscopy videos acquired during regular colonoscopic procedures and demonstrated promising results.

  15. Nonneoplastic polypectomy during screening colonoscopy: the impact on polyp detection rate, adenoma detection rate, and overall cost.

    PubMed

    Atia, Mary A; Patel, Neal C; Ratuapli, Shiva K; Boroff, Erika S; Crowell, Michael D; Gurudu, Suryakanth R; Faigel, Douglas O; Leighton, Jonathan A; Ramirez, Francisco C

    2015-08-01

    The frequency of nonneoplastic polypectomy (NNP) and its impact on the polyp detection rate (PDR) is unknown. The correlation between NNP and adenoma detection rate (ADR) and its impact on the cost of colonoscopy has not been investigated. To determine the rate of NNP in screening colonoscopy, the impact of NNP on the PDR, and the correlation of NNP with ADR. The increased cost of NNP during screening colonoscopy also was calculated. We reviewed all screening colonoscopies. PDR and ADR were calculated. We then calculated a nonneoplastic polyp detection rate (patients with ≥1 nonneoplastic polyp). Tertiary-care referral center. Patients who underwent screening colonoscopies from 2010 to 2011. Colonoscopy. ADR, PDR, NNP rate. A total of 1797 colonoscopies were reviewed. Mean (±standard deviation) PDR was 47.7%±12.0%, and mean ADR was 27.3%±6.9%. The overall NNP rate was 10.4%±7.1%, with a range of 2.4% to 28.4%. Among all polypectomies (n=2061), 276 were for nonneoplastic polyps (13.4%). Endoscopists with a higher rate of nonneoplastic polyp detection were more likely to detect an adenoma (odds ratio 1.58; 95% confidence interval, 1.1-1.2). With one outlier excluded, there was a strong correlation between ADR and NNP (r=0.825; P<.001). The increased cost of removal of nonneoplastic polyps was $32,963. Retrospective study. There is a strong correlation between adenoma detection and nonneoplastic polyp detection. The etiology is unclear, but nonneoplastic polyp detection rate may inflate the PDR for some endoscopists. NNP also adds an increased cost. Increasing the awareness of endoscopic appearances through advanced imaging techniques of normal versus neoplastic tissue may be an area to improve cost containment in screening colonoscopy. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  16. Queue position in the endoscopic schedule impacts effectiveness of colonoscopy.

    PubMed

    Lee, Alexander; Iskander, John M; Gupta, Nitin; Borg, Brian B; Zuckerman, Gary; Banerjee, Bhaskar; Gyawali, C Prakash

    2011-08-01

    Endoscopist fatigue potentially impacts colonoscopy. Fatigue is difficult to quantitate, but polyp detection rates between non-fatigued and fatigued time periods could represent a surrogate marker. We assessed whether timing variables impacted polyp detection rates at a busy tertiary care endoscopy suite. Consecutive patients undergoing colonoscopy were retrospectively identified. Indications, clinical demographics, pre-procedural, and procedural variables were extracted from chart review; colonoscopy findings were determined from the procedure reports. Three separate timing variables were assessed as surrogate markers for endoscopist fatigue: morning vs. afternoon procedures, start times throughout the day, and queue position, a unique variable that takes into account the number of procedures performed before the colonoscopy of interest. Univariate and multivariate analyses were performed to determine whether timing variables and other clinical, pre-procedural, and procedural variables predicted polyp detection. During the 4-month study period, 1,083 outpatient colonoscopy procedures (57.5±0.5 years, 59.5% female) were identified, performed by 28 endoscopists (mean 38.7 procedures/endoscopist), with a mean polyp detection rate of 0.851/colonoscopy. At least, one adenoma was detected in 297 procedures (27.4%). A 12.4% reduction in mean detected polyps was detected between morning and afternoon procedures (0.90±0.06 vs. 0.76±0.06, P=0.15). Using start time on a continuous scale, however, each elapsed hour in the day was associated with a 4.6% reduction in polyp detection (P=0.005). When queue position was assessed, a 5.4% reduction in polyp detection was noted with each increase in queue position (P=0.016). These results remained significant when controlled for each individual endoscopist. Polyp detection rates decline as time passes during an endoscopist's schedule, potentially from endoscopist fatigue. Queue position may be a novel surrogate measure for operator fatigue.

  17. Endoscopy and polyps-diagnostic and therapeutic advances in management

    PubMed Central

    Steele, Scott R; Johnson, Eric K; Champagne, Bradley; Davis, Brad; Lee, Sang; Rivadeneira, David; Ross, Howard; Hayden, Dana A; Maykel, Justin A

    2013-01-01

    Despite multiple efforts aimed at early detection through screening, colon cancer remains the third leading cause of cancer-related deaths in the United States, with an estimated 51000 deaths during 2013 alone. The goal remains to identify and remove benign neoplastic polyps prior to becoming invasive cancers. Polypoid lesions of the colon vary widely from hyperplastic, hamartomatous and inflammatory to neoplastic adenomatous growths. Although these lesions are all benign, they are common, with up to one-quarter of patients over 60 years old will develop pre-malignant adenomatous polyps. Colonoscopy is the most effective screening tool to detect polyps and colon cancer, although several studies have demonstrated missed polyp rates from 6%-29%, largely due to variations in polyp size. This number can be as high as 40%, even with advanced (> 1 cm) adenomas. Other factors including sub-optimal bowel preparation, experience of the endoscopist, and patient anatomical variations all affect the detection rate. Additional challenges in decision-making exist when dealing with more advanced, and typically larger, polyps that have traditionally required formal resection. In this brief review, we will explore the recent advances in polyp detection and therapeutic options. PMID:23885138

  18. Next-generation narrow band imaging system for colonic polyp detection: a prospective multicenter randomized trial.

    PubMed

    Horimatsu, Takahiro; Sano, Yasushi; Tanaka, Shinji; Kawamura, Takuji; Saito, Shoichi; Iwatate, Mineo; Oka, Shiro; Uno, Koji; Yoshimura, Kenichi; Ishikawa, Hideki; Muto, Manabu; Tajiri, Hisao

    2015-07-01

    Previous studies have yielded conflicting results on the colonic polyp detection rate with narrow-band imaging (NBI) compared with white-light imaging (WLI). We compared the mean number of colonic polyps detected per patient for NBI versus WLI using a next-generation NBI system (EVIS LUCERA ELITE; Olympus Medical Systems) used with standard-definition (SD) colonoscopy and wide-angle (WA) colonoscopy. this study is a 2 × 2 factorial, prospective, multicenter randomized controlled trial. this study was conducted at five academic centers in Japan. patients were allocated to one of four groups: (1) WLI with SD colonoscopy (H260AZI), (2) NBI with SD colonoscopy (H260AZI), (3) WLI with WA colonoscopy (CF-HQ290), and (4) NBI with WA colonoscopy (CF-HQ290). the mean numbers of polyps detected per patient were compared between the four groups: WLI with/without WA colonoscopy and NBI with/without WA colonoscopy. Of the 454 patients recruited, 431 patients were enrolled. The total numbers of polyps detected by WLI with SD, NBI with SD, WLI with WA, and NBI with WA were 164, 176, 188, and 241, respectively. The mean number of polyps detected per patient was significantly higher in the NBI group than in the WLI group (2.01 vs 1.56; P = 0.032). The rate was not higher in the WA group than in the SD group (1.97 vs 1.61; P = 0.089). Although WA colonoscopy did not improve the polyp detection, next-generation NBI colonoscopy represents a significant improvement in the detection of colonic polyps.

  19. The diagnostic accuracy of transabdominal ultrasonography needs to be considered when managing gallbladder polyps.

    PubMed

    French, Daniel G; Allen, Philippe D; Ellsmere, James C

    2013-11-01

    Transabdominal ultrasonography (TAUS) is the most commonly used modality to diagnose gallbladder (GB) disease. GB polyps are reported in 1-5.6 % of TAUS studies. Histopathologic studies suggest that there is a relationship between GB polyps and GB cancer. Previous literature suggests GB polyps reported on TAUS do not correlate well with histological findings. There have been recent advances in TAUS technology. We hypothesize the recent advances in TAUS technology have improved the accuracy of TAUS for diagnosing GB polyps. Radiology and pathology databases at our tertiary care center were retrospectively searched between January 1, 2000, and December 31, 2010. Ultrasound reports that suggested a GB polyp was present on TAUS were correlated to histopathology in cases where a cholecystectomy was performed. The pathology reports where a GB polyp was found were correlated with preoperative TAUS reports. There were 102,740 TAUS reports referring to the GB, of which 6,612 (6.4 %) contained search terms suggesting a GB polyp was present. There were 13,278 cholecystectomy pathology reports, of which 159 (1.2 %) included a diagnosis of GB polyp. TAUS detected only 50 % of the polyps identified on histopathology. The sensitivity and specificity of TAUS for diagnosing GB polyps were 50.0 and 98.3 %, respectively. The positive and negative predictive values were 10.5 and 99.8 %. Despite improvement in TAUS technology, the accuracy for GB polyps remains poor. This needs to be considered when managing patients with TAUS-detected GB polyps. We recommend that the decision to operate on TAUS-detected GB polyps be largely based on symptoms, and following GB polyps with TAUS should be discouraged.

  20. Reduction in training time of a deep learning model in detection of lesions in CT

    NASA Astrophysics Data System (ADS)

    Makkinejad, Nazanin; Tajbakhsh, Nima; Zarshenas, Amin; Khokhar, Ashfaq; Suzuki, Kenji

    2018-02-01

    Deep learning (DL) emerged as a powerful tool for object detection and classification in medical images. Building a well-performing DL model, however, requires a huge number of images for training, and it takes days to train a DL model even on a cutting edge high-performance computing platform. This study is aimed at developing a method for selecting a "small" number of representative samples from a large collection of training samples to train a DL model for the could be used to detect polyps in CT colonography (CTC), without compromising the classification performance. Our proposed method for representative sample selection (RSS) consists of a K-means clustering algorithm. For the performance evaluation, we applied the proposed method to select samples for the training of a massive training artificial neural network based DL model, to be used for the classification of polyps and non-polyps in CTC. Our results show that the proposed method reduce the training time by a factor of 15, while maintaining the classification performance equivalent to the model trained using the full training set. We compare the performance using area under the receiveroperating- characteristic curve (AUC).

  1. Detection of flat colorectal polyps at screening CT colonography in comparison with conventional polypoid lesions.

    PubMed

    Sakamoto, Takashi; Mitsuzaki, Katsuhiko; Utsunomiya, Daisuke; Matsuda, Katsuhiko; Yamamura, Sadahiro; Urata, Joji; Kawakami, Megumi; Yamashita, Yasuyuki

    2012-09-01

    Although the screening of small, flat polyps is clinically important, the role of CT colonography (CTC) screening in their detection has not been thoroughly investigated. To evaluate the detection capability and usefulness of CTC in the screening of flat and polypoid lesions by comparing CTC with optic colonoscopy findings as the gold standard. We evaluated the CTC detection capability for flat colorectal polyps with a flat surface and a height not exceeding 3 mm (n = 42) by comparing to conventional polypoid lesions (n = 418) according to the polyp diameter. Four types of reconstruction images including multiplanar reconstruction, volume rendering, virtual gross pathology, and virtual endoscopic images were used for visual analysis. We compared the abilities of the four reconstructions for polyp visualization. Detection sensitivity for flat polyps was 31.3%, 44.4%, and 87.5% for lesions measuring 2-3 mm, 4-5 mm, and ≥6 mm, respectively; the corresponding sensitivity for polypoid lesions was 47.6%, 79.0%, and 91.7%. The overall sensitivity for flat lesions (47.6%) was significantly lower than polypoid lesions (64.1%). Virtual endoscopic imaging showed best visualization among the four reconstructions. Colon cancers were detected in eight patients by optic colonoscopy, and CTC detected colon cancers in all eight patients. CTC using 64-row multidetector CT is useful for colon cancer screening to detect colorectal polyps while the detection of small, flat lesions is still challenging.

  2. Back-to-back colon capsule endoscopy and optical colonoscopy in colorectal cancer screening individuals.

    PubMed

    Kobaek-Larsen, M; Kroijer, R; Dyrvig, A-K; Buijs, M M; Steele, R J C; Qvist, N; Baatrup, G

    2018-06-01

    The aim was to determine the polyp detection rate and per-patient sensitivity for polyps > 9 mm of colon capsule endoscopy (CCE) compared with colonoscopy as well as the diagnostic accuracy of CCE. Individuals who had a positive immunochemical faecal occult blood test during screening had investigator blinded CCE and colonoscopy. Participants underwent repeat endoscopy if significant lesions detected by CCE were considered to have been missed by colonoscopy. There were 253 participants. The polyp detection rate was significantly higher in CCE compared with colonoscopy (P = 0.02). The per-patient sensitivity for > 9 mm polyps for CCE and colonoscopy was 87% (95% CI: 83-91%) and 88% (95% CI: 84-92%) respectively. In participants with complete CCE and colonoscopy examinations (N = 126), per-patient sensitivity of > 9 mm polyps in CCE (97%; 95% CI: 94-100%) was superior to colonoscopy (89%; 95% CI: 84-94%). A complete capsule endoscopy examination (N = 134) could detect patients with intermediate or greater risk (according to the European guidelines) with an accuracy, sensitivity, specificity and positivity rate of 79%, 93%, 69% and 58% respectively, using a cut-off of at least one polyp > 10 mm or more than two polyps. CCE is superior to colonoscopy in polyp detection rate and per-patient sensitivity to > 9 mm polyps, but only in complete CCE examinations. The rate of incomplete CCE examinations must be improved. Colorectal Disease © 2017 The Association of Coloproctology of Great Britain and Ireland.

  3. Flat colon polyps: what should radiologists know?

    PubMed

    Ignjatovic, A; Burling, D; Ilangovan, R; Clark, S K; Taylor, S A; East, J E; Saunders, B P

    2010-12-01

    With the recent publication of international computed tomography (CT) colonography standards, which aim to improve quality of examinations, this review informs radiologists about the significance of flat polyps (adenomas and hyperplastic polyps) in colorectal cancer pathways. We describe flat polyp classification systems and propose how flat polyps should be reported to ensure patient management strategies are based on polyp morphology as well as size. Indeed, consistency when describing flat polyps is of increasing importance given the strengthening links between CT colonography and endoscopy. Copyright © 2010 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  4. CT colonography without cathartic preparation: positive predictive value and patient experience in clinical practice.

    PubMed

    Zueco Zueco, Carmen; Sobrido Sampedro, Carolina; Corroto, Juan D; Rodriguez Fernández, Paula; Fontanillo Fontanillo, Manuela

    2012-06-01

    To determine the positive predictive value (PPV) for polyps ≥ 6 mm detected at CT colonography (CTC) performed without cathartic preparation, with low-dose iodine faecal tagging regimen and to evaluate patient experience. 1920 average-risk patients underwent CTC without cathartic preparation. Faecal tagging was performed by diatrizoate meglumine and diatrizoate sodium at a total dose of 60 ml (22.2 g of iodine).The standard interpretation method was primary 3D with 2D problem solving. We calculated per-patient and per-polyp PPV in relation to size and morphology. All colonic segments were evaluated for image quality (faecal tagging, amount of liquid and solid residual faeces and luminal distension). Patients completed a questionnaire before and after CTC to assess preparation and examination experience. Per-polyp PPV for detected lesions of ≥ 6 mm, 6-9 mm, ≥ 10 mm and ≥ 30 mm were 94.3%, 93.1%, 94.7% and 98%, respectively. Per-polyp PPV, according to lesion morphology, was 94.6%, 97.3% and 85.1% for sessile, pedunculated and flat polyps, respectively. Per-patient PPV was 92.8%. Preparation without frank cathartics was reported to cause minimal discomfort by 78.9% of patients. CTC without cathartic preparation and low-dose iodine faecal tagging may yield high PPVs for lesions ≥ 6 mm and is well accepted by patients. • Computed tomographic colonography (CTC) without cathartic preparation is well accepted by patients • Cathartic-free faecal tagging CTC yields high positive predictive values • CTC without cathartic preparation could improve uptake of colorectal cancer screening.

  5. Glycoprotein expression by adenomatous polyps of the colon

    NASA Astrophysics Data System (ADS)

    Roney, Celeste A.; Xie, Jianwu; Xu, Biying; Jabour, Paul; Griffiths, Gary; Summers, Ronald M.

    2008-03-01

    Colon cancer is the second leading cause of cancer related deaths in the United States. Specificity in diagnostic imaging for detecting colorectal adenomas, which have a propensity towards malignancy, is desired. Adenomatous polyp specimens of the colon were obtained from the mouse model of colorectal cancer called adenomatous polyposis coli-multiple intestinal neoplasia (APC Min). Histological evaluation, by the legume protein Ulex europaeus agglutinin I (UEA-1), determined expression of the glycoprotein α-L-fucose. FITC-labelled UEA-1 confirmed overexpression of the glycoprotein by the polyps on fluorescence microscopy in 17/17 cases, of which 13/17 included paraffin-fixed mouse polyp specimens. In addition, FITC-UEA-1 ex vivo multispectral optical imaging of 4/17 colonic specimens displayed over-expression of the glycoprotein by the polyps, as compared to non-neoplastic mucosa. Here, we report the surface expression of α-L-fucosyl terminal residues by neoplastic mucosal cells of APC specimens of the mouse. Glycoprotein expression was validated by the carbohydrate binding protein UEA-1. Future applications of this method are the development of agents used to diagnose cancers by biomedical imaging modalities, including computed tomographic colonography (CTC). UEA-1 targeting to colonic adenomas may provide a new avenue for the diagnosis of colorectal carcinoma by CT imaging.

  6. Automatic Detection and Classification of Colorectal Polyps by Transferring Low-Level CNN Features From Nonmedical Domain.

    PubMed

    Zhang, Ruikai; Zheng, Yali; Mak, Tony Wing Chung; Yu, Ruoxi; Wong, Sunny H; Lau, James Y W; Poon, Carmen C Y

    2017-01-01

    Colorectal cancer (CRC) is a leading cause of cancer deaths worldwide. Although polypectomy at early stage reduces CRC incidence, 90% of the polyps are small and diminutive, where removal of them poses risks to patients that may outweigh the benefits. Correctly detecting and predicting polyp type during colonoscopy allows endoscopists to resect and discard the tissue without submitting it for histology, saving time, and costs. Nevertheless, human visual observation of early stage polyps varies. Therefore, this paper aims at developing a fully automatic algorithm to detect and classify hyperplastic and adenomatous colorectal polyps. Adenomatous polyps should be removed, whereas distal diminutive hyperplastic polyps are considered clinically insignificant and may be left in situ . A novel transfer learning application is proposed utilizing features learned from big nonmedical datasets with 1.4-2.5 million images using deep convolutional neural network. The endoscopic images we collected for experiment were taken under random lighting conditions, zooming and optical magnification, including 1104 endoscopic nonpolyp images taken under both white-light and narrowband imaging (NBI) endoscopy and 826 NBI endoscopic polyp images, of which 263 images were hyperplasia and 563 were adenoma as confirmed by histology. The proposed method identified polyp images from nonpolyp images in the beginning followed by predicting the polyp histology. When compared with visual inspection by endoscopists, the results of this study show that the proposed method has similar precision (87.3% versus 86.4%) but a higher recall rate (87.6% versus 77.0%) and a higher accuracy (85.9% versus 74.3%). In conclusion, automatic algorithms can assist endoscopists in identifying polyps that are adenomatous but have been incorrectly judged as hyperplasia and, therefore, enable timely resection of these polyps at an early stage before they develop into invasive cancer.

  7. Risk and Cost-effectiveness of Surveillance Followed by Cholecystectomy for Gallbladder Polyps.

    PubMed

    Cairns, Vaux; Neal, Christopher P; Dennison, Ashely R; Garcea, Giuseppe

    2012-12-01

    OBJECTIVE To ascertain the best management options for patients presenting with gallbladder polyps. DESIGN Retrospective case-note analysis. SETTING Tertiary referral teaching hospital practice. PATIENTS Patients with ultrasonography-detected gallbladder polyps. INTERVENTIONS Ultrasonography surveillance or surgery. MAIN OUTCOME MEASURES Demographic data and size and number of polyps were recorded as well as size increase and histological findings. Detection rates for potentially neoplastic and frankly neoplastic polyps were recorded and compared with complication rates from cholecystectomy. Cost-effectiveness of ultrasonography surveillance was examined. RESULTS Nine hundred eighty-six patients were identified and 467 patients underwent further follow-up. Only 6.6% of polyps exhibited an increase in size over the surveillance period. Polyps that subsequently progressed in size on surveillance had a significantly greater diameter at first presentation than those polyps that remained static (7 mm vs 5 mm, respectively) (P < .05). Only 3.7% of resected polyps had malignant or potentially malignant histology. Size greater than 10 mm and increase in size during surveillance predicted neoplastic potential. CONCLUSIONS A surveillance with or without selective surgery policy could potentially detect and prevent 5.4 gallbladder cancers per 1000 individuals per year with a cost saving of more than £130 000 (US $201 676) per year. Cancer prevention benefits would exceed the risk ratios from cholecystectomy complications. Polyps greater than 10 mm should be resected; those between 5 and 10 mm should be under ultrasonography surveillance.

  8. Automatic polyp detection in colonoscopy videos

    NASA Astrophysics Data System (ADS)

    Yuan, Zijie; IzadyYazdanabadi, Mohammadhassan; Mokkapati, Divya; Panvalkar, Rujuta; Shin, Jae Y.; Tajbakhsh, Nima; Gurudu, Suryakanth; Liang, Jianming

    2017-02-01

    Colon cancer is the second cancer killer in the US [1]. Colonoscopy is the primary method for screening and prevention of colon cancer, but during colonoscopy, a significant number (25% [2]) of polyps (precancerous abnormal growths inside of the colon) are missed; therefore, the goal of our research is to reduce the polyp miss-rate of colonoscopy. This paper presents a method to detect polyp automatically in a colonoscopy video. Our system has two stages: Candidate generation and candidate classification. In candidate generation (stage 1), we chose 3,463 frames (including 1,718 with-polyp frames) from real-time colonoscopy video database. We first applied processing procedures, namely intensity adjustment, edge detection and morphology operations, as pre-preparation. We extracted each connected component (edge contour) as one candidate patch from the pre-processed image. With the help of ground truth (GT) images, 2 constraints were implemented on each candidate patch, dividing and saving them into polyp group and non-polyp group. In candidate classification (stage 2), we trained and tested convolutional neural networks (CNNs) with AlexNet architecture [3] to classify each candidate into with-polyp or non-polyp class. Each with-polyp patch was processed by rotation, translation and scaling for invariant to get a much robust CNNs system. We applied leave-2-patients-out cross-validation on this model (4 of 6 cases were chosen as training set and the rest 2 were as testing set). The system accuracy and sensitivity are 91.47% and 91.76%, respectively.

  9. Segmentation algorithm of colon based on multi-slice CT colonography

    NASA Astrophysics Data System (ADS)

    Hu, Yizhong; Ahamed, Mohammed Shabbir; Takahashi, Eiji; Suzuki, Hidenobu; Kawata, Yoshiki; Niki, Noboru; Suzuki, Masahiro; Iinuma, Gen; Moriyama, Noriyuki

    2012-02-01

    CT colonography is a radiology test that looks at people's large intestines(colon). CT colonography can screen many options of colon cancer. This test is used to detect polyps or cancers of the colon. CT colonography is safe and reliable. It can be used if people are too sick to undergo other forms of colon cancer screening. In our research, we proposed a method for automatic segmentation of the colon from abdominal computed Tomography (CT) images. Our multistage detection method extracted colon and spited colon into different parts according to the colon anatomy information. We found that among the five segmented parts of the colon, sigmoid (20%) and rectum (50%) are more sensitive toward polyps and masses than the other three parts. Our research focused on detecting the colon by the individual diagnosis of sigmoid and rectum. We think it would make the rapid and easy diagnosis of colon in its earlier stage and help doctors for analysis of correct position of each part and detect the colon rectal cancer much easier.

  10. Exploration of Analysis Methods for Diagnostic Imaging Tests: Problems with ROC AUC and Confidence Scores in CT Colonography

    PubMed Central

    Mallett, Susan; Halligan, Steve; Collins, Gary S.; Altman, Doug G.

    2014-01-01

    Background Different methods of evaluating diagnostic performance when comparing diagnostic tests may lead to different results. We compared two such approaches, sensitivity and specificity with area under the Receiver Operating Characteristic Curve (ROC AUC) for the evaluation of CT colonography for the detection of polyps, either with or without computer assisted detection. Methods In a multireader multicase study of 10 readers and 107 cases we compared sensitivity and specificity, using radiological reporting of the presence or absence of polyps, to ROC AUC calculated from confidence scores concerning the presence of polyps. Both methods were assessed against a reference standard. Here we focus on five readers, selected to illustrate issues in design and analysis. We compared diagnostic measures within readers, showing that differences in results are due to statistical methods. Results Reader performance varied widely depending on whether sensitivity and specificity or ROC AUC was used. There were problems using confidence scores; in assigning scores to all cases; in use of zero scores when no polyps were identified; the bimodal non-normal distribution of scores; fitting ROC curves due to extrapolation beyond the study data; and the undue influence of a few false positive results. Variation due to use of different ROC methods exceeded differences between test results for ROC AUC. Conclusions The confidence scores recorded in our study violated many assumptions of ROC AUC methods, rendering these methods inappropriate. The problems we identified will apply to other detection studies using confidence scores. We found sensitivity and specificity were a more reliable and clinically appropriate method to compare diagnostic tests. PMID:25353643

  11. Exploration of analysis methods for diagnostic imaging tests: problems with ROC AUC and confidence scores in CT colonography.

    PubMed

    Mallett, Susan; Halligan, Steve; Collins, Gary S; Altman, Doug G

    2014-01-01

    Different methods of evaluating diagnostic performance when comparing diagnostic tests may lead to different results. We compared two such approaches, sensitivity and specificity with area under the Receiver Operating Characteristic Curve (ROC AUC) for the evaluation of CT colonography for the detection of polyps, either with or without computer assisted detection. In a multireader multicase study of 10 readers and 107 cases we compared sensitivity and specificity, using radiological reporting of the presence or absence of polyps, to ROC AUC calculated from confidence scores concerning the presence of polyps. Both methods were assessed against a reference standard. Here we focus on five readers, selected to illustrate issues in design and analysis. We compared diagnostic measures within readers, showing that differences in results are due to statistical methods. Reader performance varied widely depending on whether sensitivity and specificity or ROC AUC was used. There were problems using confidence scores; in assigning scores to all cases; in use of zero scores when no polyps were identified; the bimodal non-normal distribution of scores; fitting ROC curves due to extrapolation beyond the study data; and the undue influence of a few false positive results. Variation due to use of different ROC methods exceeded differences between test results for ROC AUC. The confidence scores recorded in our study violated many assumptions of ROC AUC methods, rendering these methods inappropriate. The problems we identified will apply to other detection studies using confidence scores. We found sensitivity and specificity were a more reliable and clinically appropriate method to compare diagnostic tests.

  12. Prevalence of flat lesions in a large screening population and their role in colonoscopy quality improvement.

    PubMed

    Reinhart, K; Bannert, C; Dunkler, D; Salzl, P; Trauner, M; Renner, F; Knoflach, P; Ferlitsch, A; Weiss, W; Ferlitsch, M

    2013-01-01

    Flat lesions pose new challenges for endoscopists, but the importance of detecting them is still controversial. Most screening studies do not survey macroscopic polyp morphology. The aims were to evaluate the percentage of flat polyp findings in a large asymptomatic adult screening population (n = 52 521), to assess the impact of shape and size on malignant transformation, and to assess the role of flat lesions regarding quality assurance in colorectal cancer prevention. Retrospective analysis of screening colonoscopies performed between 2007 and 2011 according to the Austrian "Quality management for colon cancer prevention" program. 17 771 patients with polyps were included in the study. Patients with flat polyps represented 24.2 % (n = 4293), 62.4 % (n = 11 097) were classified as having sessile and 13.4 % (n = 2381) as pedunculated polyps. Among those with flat polyps 51.4 % had adenomas (n = 2207). High grade dysplasia (HGD) was found in 2.1 % (n = 47) of flat adenomas, in 1.5 % (n = 89) of sessile adenomas and 4.7 % (n = 92) of pedunculated adenomas (P < 0.0001. The risk for containing HGD was 1.0 % for flat lesions ≤ 10 mm in size compared with 10.3 % for lesions > 10 mm, and 1.0 % for polypoid lesions ≤ 10 mm compared with 9.3 % for lesions > 10 mm (P < 0.0001). Multivariable logistic regression showed that polyp size (P < 0.0001) but not polyp shape (P = 0.438) is an independent predictor for HGD. Adenoma detection rate (ADR) correlated weakly with the flat polyp detection rate (Pearson r = 0.24). Malignant potential of polyps is mostly affected by size but not by shape. Since flat polyp detection rate only correlates poorly with ADR we do not recommend its incorporation in quality assured screening colonoscopy. © Georg Thieme Verlag KG Stuttgart · New York.

  13. [Colonic polyps diagnosis by conventional video colonoscopes and chromoscopy with indigo carmine dye solution].

    PubMed

    Nakao, Frank Shigueo; Araújo, Isabella Saraiva; Ornellas, Laura Cotta; Cury, Marcelo de Sousa; Ferrari, Angelo Paulo

    2002-01-01

    Magnification colonoscopy and contrast chromoscopy with indigo carmine dye solution have been used to differentiate neoplastic polyps (adenomas and adenocarcinomas) from non-neoplastic (hyperplastic, inflammatory, juvenile) in an attempt to obviate endoscopic polypectomy. On the other hand, little published information exists concerning conventional video colonoscopes and chromoscopy for polyp histology prediction. Aim - To assess usefullness of conventional video colonoscopes and contrast chromoscopy with indigo carmine solution for differential diagnosis of colon polyps. In a routine colonoscopy series, we performed chromoscopy with conventional video colonoscopes before endoscopic excision of detected polyps. If a sulcus pattern was observed on the surface of the lesion, it was classified as neoplastic. Polyps were classified as non-neoplastic if no sulcus was detected on its surface. These observations were then compared with histology. In the study period (18 months), we detected 133 polyps in 53 patients. We were able to compare results of histology and chromoscopy in 126 lesions. The sensitivity, specificity, diagnostic accuracy, negative predictive value, and positive predictive value were 56,4%, 79,2%, 65,1%, 52,8%, and 81,5%, respectively. On the base of the presented data, we concluded that conventional video colonoscopes and contrast chromoscopy with indigo carmine solution is not a good technique for differential diagnosis of colon polyps.

  14. Fully convolutional neural networks for polyp segmentation in colonoscopy

    NASA Astrophysics Data System (ADS)

    Brandao, Patrick; Mazomenos, Evangelos; Ciuti, Gastone; Caliò, Renato; Bianchi, Federico; Menciassi, Arianna; Dario, Paolo; Koulaouzidis, Anastasios; Arezzo, Alberto; Stoyanov, Danail

    2017-03-01

    Colorectal cancer (CRC) is one of the most common and deadliest forms of cancer, accounting for nearly 10% of all forms of cancer in the world. Even though colonoscopy is considered the most effective method for screening and diagnosis, the success of the procedure is highly dependent on the operator skills and level of hand-eye coordination. In this work, we propose to adapt fully convolution neural networks (FCN), to identify and segment polyps in colonoscopy images. We converted three established networks into a fully convolution architecture and fine-tuned their learned representations to the polyp segmentation task. We validate our framework on the 2015 MICCAI polyp detection challenge dataset, surpassing the state-of-the-art in automated polyp detection. Our method obtained high segmentation accuracy and a detection precision and recall of 73.61% and 86.31%, respectively.

  15. Cancer emerging from the recurrence of sessile serrated adenoma/polyp resected endoscopically 5 years ago.

    PubMed

    Chino, A; Nagayama, S; Ishikawa, H; Morishige, K; Kishihara, T; Arai, M; Sugiura, Y; Motoi, N; Yamamoto, N; Tamegai, Y; Igarashi, M

    2016-01-01

    Since the serrated neoplastic pathway has been regarded as an important pathway of colorectal carcinogenesis, few reports have been published on clinical cases of cancer derived from sessile serrated adenoma/polyp, especially on recurrence after resected sessile serrated adenoma/polyp. An elderly woman underwent endoscopic mucosal resection of a flat elevated lesion, 30 mm in diameter, in the ascending colon; the histopathological diagnosis at that time was a hyperplastic polyp, now known as sessile serrated adenoma/polyp. Five years later, cancer due to the malignant transformation of the sessile serrated adenoma/polyp was detected at the same site. The endoscopic diagnosis was a deep invasive carcinoma with a remnant sessile serrated adenoma/polyp component. The carcinoma was surgically removed, and the pathological diagnosis was an adenocarcinoma with sessile serrated adenoma/polyp, which invaded the muscularis propria. The surgically removed lesion did not have a B-RAF mutation in either the sessile serrated adenoma/polyp or the carcinoma; moreover, the initial endoscopically resected lesion also did not have a B-RAF mutation. Immunohistochemistry confirmed negative MLH1 protein expression in only the cancer cells. Lynch syndrome was not detected on genomic examination. The lesion was considered to be a cancer derived from sessile serrated adenoma/polyp recurrence after endoscopic resection, because both the surgically and endoscopically resected lesions were detected at the same location and had similar pathological characteristics, with a serrated structure and low-grade atypia. Furthermore, both lesions had a rare diagnosis of a sessile serrated adenoma/polyp without B-RAF mutation. This report highlights the need for the follow-up colonoscopy after endoscopic resection and rethinking our resection procedures to improve treatment. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. CT biliary cystoscopy of gallbladder polyps

    PubMed Central

    Lou, Ming-Wu; Hu, Wei-Dong; Fan, Yi; Chen, Jin-Hua; E, Zhan-Sen; Yang, Guang-Fu

    2004-01-01

    AIM: CT virtual endoscopy has been used in the study of various organs of body including the biliary tract, however, CT virtual endoseopy in diagnosis of gallbladder polyps has not yet been reported. This study was to evaluate the diagnostic value of CT virtual endoscopy in polyps of the gallbladder. METHODS: Thirty-two cases of gallbladder polyps were examined by CT virtual endoscopy, ultrasound, CT scan with oral biliary contrast separately and confirmed by operation and pathology. CT biliary cystoscopic findings were analyzed and compared with those of ultrasound and CT scan with oral biliary contrast, and evaluated in comparison with operative and pathologic findings in all cases. RESULTS: The detection rate of gallbladder polyps was 93.8%(90/96), 96.9%(93/96) and 79.2%(76/96) for CT cystoscopy, ultrasound and CT scan with oral contrast, respectively. CT biliary cystoscopy corresponded well with ultrasound as well as pathology in demonstrating the location, size and configuration of polyps. CT endoscopy was superior to ultrasound in viewing the polyps in a more precise way, 3 dimensionally from any angle in space, and showing the surface in details. CT biliary cystoscopy was also superior to CT scan with oral biliary contrast in terms of observation of the base of polyps for the presence of a pedicle, detection rates as well as image quality. The smallest polyp detected by CT biliary cystoscopy was measured 1.5 mm×2.2 mm×2.5 mm. CONCLUSION: CT biliary cystoscopy is a non-invasive and accurate technique for diagnosis and management of gallbladder polyps. PMID:15069726

  17. Withdrawal times and associated factors in colonoscopy: a quality assurance multicenter assessment.

    PubMed

    Overholt, Bergein F; Brooks-Belli, Linda; Grace, Michael; Rankin, Kristin; Harrell, Royce; Turyk, Mary; Rosenberg, Fred B; Barish, Robert W; Gilinsky, Norman H

    2010-04-01

    To evaluate the use and impact of the recommended withdrawal time of at least 6 minutes from the cecum in colonoscopy in multiple gastroenterology endoscopy ambulatory surgery centers serving a wide geographical area. An observational prospective multicenter quality assurance review was conducted in 49 ambulatory surgery centers in 17 states with 315 gastroenterologists. There was no intervention with this quality assessment program as care of patients and the routine of gastroenterologists continued as standard practice. Multivariable analysis was applied to the database to examine factors affecting withdrawal time and polyp detection. There were 15,955 consecutive qualified patients receiving colonoscopies in a designated 4-week period. Gastroenterologists with average withdrawal times of 6 minutes or more in patients with no polyps were 1.8 times more likely to detect 1 or more polyps and had a significantly higher rate (P<0.0001) of polyp detection in patients with findings of polyps compared to gastroenterologists with average withdrawal times of less than 6 minutes in patients with no polyps. For patients with no pathology, the mean time of withdrawal was 6.98 (SD=4.34) minutes and for patients with pathology mean time of withdrawal was 11.27 (SD=6.71) minutes. Strongest predictors of withdrawal time of 6 minutes or more were presence of carcinoma (3.7 times more likely than those with no pathology), adenoma (2.0 times more likely than those with no pathology), and number of polyps visualized (1.7 times more likely for each polyp). This quality assurance assessment from standard colonoscopy practices of 315 gastroenterologists in 49 endoscopic ambulatory surgery centers serving a wide geographical area provides support for the merits of a colonoscopy withdrawal time from the cecum of 6 minutes or more to improve the detection of polyps.

  18. Update on imaging of Peutz-Jeghers syndrome

    PubMed Central

    Tomas, Catherine; Soyer, Philippe; Dohan, Anthony; Dray, Xavier; Boudiaf, Mourad; Hoeffel, Christine

    2014-01-01

    Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant disease linked to a mutation of the STK 11 gene and is characterized by the development of benign hamartomatous polyps in the gastrointestinal tract in association with a hyperpigmentation on the lips and oral mucosa. Patients affected by PJS have an increased risk of developing gastrointestinal and extra-digestive cancer. Malignancy most commonly occurs in the small-bowel. Extra-intestinal malignancies are mostly breast cancer and gynecological tumors or, to a lesser extent, pancreatic cancer. These polyps are also at risk of acute gastrointestinal bleeding, intussusception and bowel obstruction. Recent guidelines recommend regular small-bowel surveillance to reduce these risks associated with PJS. Small-bowel surveillance allows for the detection of large polyps and the further referral of selected PJS patients for endoscopic enteroscopy or surgery. Video capsule endoscopy, double balloon pushed enteroscopy, multidetector computed tomography and magnetic resonance enteroclysis or enterography, all of which are relatively new techniques, have an important role in the management of patients suffering from PJS. This review illustrates the pathological, clinical and imaging features of small-bowel abnormalities as well as the role and performance of the most recent imaging modalities for the detection and follow-up of PJS patients. PMID:25152588

  19. Integrating Online and Offline Three-Dimensional Deep Learning for Automated Polyp Detection in Colonoscopy Videos.

    PubMed

    Lequan Yu; Hao Chen; Qi Dou; Jing Qin; Pheng Ann Heng

    2017-01-01

    Automated polyp detection in colonoscopy videos has been demonstrated to be a promising way for colorectal cancer prevention and diagnosis. Traditional manual screening is time consuming, operator dependent, and error prone; hence, automated detection approach is highly demanded in clinical practice. However, automated polyp detection is very challenging due to high intraclass variations in polyp size, color, shape, and texture, and low interclass variations between polyps and hard mimics. In this paper, we propose a novel offline and online three-dimensional (3-D) deep learning integration framework by leveraging the 3-D fully convolutional network (3D-FCN) to tackle this challenging problem. Compared with the previous methods employing hand-crafted features or 2-D convolutional neural network, the 3D-FCN is capable of learning more representative spatio-temporal features from colonoscopy videos, and hence has more powerful discrimination capability. More importantly, we propose a novel online learning scheme to deal with the problem of limited training data by harnessing the specific information of an input video in the learning process. We integrate offline and online learning to effectively reduce the number of false positives generated by the offline network and further improve the detection performance. Extensive experiments on the dataset of MICCAI 2015 Challenge on Polyp Detection demonstrated the better performance of our method when compared with other competitors.

  20. BowelScope: Accuracy of Detection Using ENdocuff Optimisation of Mucosal Abnormalities

    ClinicalTrials.gov

    2017-05-05

    Colorectal Neoplasms; Colonic Polyp; Adenoma; Neoplasia GI; Digestive System Neoplasms; Intestinal Neoplasms; Neoplasms, Glandular and Epithelial; Digestive Disease; Intestinal Diseases; Colonic Diseases; Rectal Diseases; Intestinal Polyps; Polyps; Pathological Conditions, Anatomical

  1. Inflammatory myoglandular polyp--a rare but distinct type of colorectal polyps.

    PubMed

    Becheanu, Gabriel; Stamm, Bernhard

    2003-01-01

    The aim of this paper was to report another example of a rare type of colorectal polyps, the inflammatory myoglandular polyp, and to reaffirm this type of polyp as a distinct entity. This solitary pedunculated polyp was detected after a single episode of rectal bleeding. It was situated in the sigmoid colon, measured 2.5 cm in greatest diameter, and was composed almost exclusively of smooth muscles and hyperplastic glands. The patient had neither chronic colitis nor diverticula. Clinical presentation, localization, and histology give this type of polyp a unique appearance and justify its designation as a separate entity.

  2. Recurrent giant fibrovascular polyp of the esophagus

    PubMed Central

    Lee, Ser Yee; Chan, Weng Hoong; Sivanandan, Ranjiv; Lim, Dennis Teck Hock; Wong, Wai Keong

    2009-01-01

    Giant fibrovascular polyps of the esophagus and hypopharynx are rare benign esophageal tumors. They arise most commonly in the upper esophagus and may, rarely, originate in the hypopharynx. They can vary significantly in size. Even though they are benign, they may be lethal due to either bleeding or, rarely, asphyxiation if a large polyp is regurgitated. Patients commonly present with dysphagia or hematemesis. The polyps may not be well visualized on endoscopy and imaging plays a vital role in aiding diagnosis as well as providing important information for pre-operative planning, such as the location of the pedicle, the vascularity of the polyp and the tissue elements of the mass. They can also be recurrent in rare cases, especially if the resection margins of the base are involved. We review the recent literature and report a case of a 61-year-old man with a recurrent giant esophageal fibrovascular polyp with illustrative contrast barium swallow, CT and intra-operative images, who required several surgeries via a combination of endoscopic, trans-oral, trans-cervical, trans-thoracic and trans-abdominal approaches. PMID:19653354

  3. Virtual Colonoscopy Screening With Ultra Low-Dose CT and Less-Stressful Bowel Preparation: A Computer Simulation Study

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Wang, Su; Li, Lihong; Fan, Yi; Lu, Hongbing; Liang, Zhengrong

    2008-10-01

    Computed tomography colonography (CTC) or CT-based virtual colonoscopy (VC) is an emerging tool for detection of colonic polyps. Compared to the conventional fiber-optic colonoscopy, VC has demonstrated the potential to become a mass screening modality in terms of safety, cost, and patient compliance. However, current CTC delivers excessive X-ray radiation to the patient during data acquisition. The radiation is a major concern for screening application of CTC. In this work, we performed a simulation study to demonstrate a possible ultra low-dose CT technique for VC. The ultra low-dose abdominal CT images were simulated by adding noise to the sinograms of the patient CTC images acquired with normal dose scans at 100 mA s levels. The simulated noisy sinogram or projection data were first processed by a Karhunen-Loeve domain penalized weighted least-squares (KL-PWLS) restoration method and then reconstructed by a filtered backprojection algorithm for the ultra low-dose CT images. The patient-specific virtual colon lumen was constructed and navigated by a VC system after electronic colon cleansing of the orally-tagged residue stool and fluid. By the KL-PWLS noise reduction, the colon lumen can successfully be constructed and the colonic polyp can be detected in an ultra low-dose level below 50 mA s. Polyp detection can be found more easily by the KL-PWLS noise reduction compared to the results using the conventional noise filters, such as Hanning filter. These promising results indicate the feasibility of an ultra low-dose CTC pipeline for colon screening with less-stressful bowel preparation by fecal tagging with oral contrast.

  4. Colonoscopy yields fewer polyps as the day progresses despite using social influence theory to reverse the trend.

    PubMed

    Kaneshiro, Marc; Ho, Andrew; Chan, Michael; Cohen, Hartley; Spiegel, Brennan M R

    2010-12-01

    We previously reported that fewer polyps are detected by colonoscopy as the day progresses, a phenomenon that could be modified with "social influence theory" by using auditing and feedback. To measure the impact of a social influence informational poster on the relationship between time of day and colonoscopy yield. Controlled before-and-after study comparing the polyp yield and time of day relationship in a historical cohort versus a 3-month intervention period. University-based Veterans Affairs medical center. Patients undergoing outpatient screening, surveillance, or diagnostic colonoscopies. Placement of informational posters in endoscopy rooms within view of operators and nurses. The poster depicted a bar graph of the previously documented hour-by-hour decreases in polyp yield coupled with prominent text: "What Time Is It Now?" Polyp yield, including secondary end point limited to adenoma detection. We performed regression to measure the effect of start time on polyp yield. There were 477 and 301 patients in the control and intervention periods, respectively. There was a negative relationship between start time and polyp yield, including adenoma detection, for both periods (P = .001). Start time remained negatively predictive of polyp and adenoma yield after adjusting for poster exposure and confounders (P = .01). Nonrandomized study design. An informational poster did not alter the relationship between colonoscopy start time and polyp yield. This strengthens the previous finding that start time may affect polyp yield and suggests that passive use of social influence theory is inadequate to modify this effect. Shortening endoscopy shifts and active auditing with feedback may be necessary. Copyright © 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  5. Clinical evaluation of endoscopic trimodal imaging for the detection and differentiation of colonic polyps.

    PubMed

    van den Broek, Frank J C; Fockens, Paul; Van Eeden, Susanne; Kara, Mohammed A; Hardwick, James C H; Reitsma, Johannes B; Dekker, Evelien

    2009-03-01

    Endoscopic trimodal imaging (ETMI) incorporates high-resolution endoscopy (HRE) and autofluorescence imaging (AFI) for adenoma detection, and narrow-band imaging (NBI) for differentiation of adenomas from nonneoplastic polyps. The aim of this study was to compare AFI with HRE for adenoma detection and to assess the diagnostic accuracy of NBI for differentiation of polyps. This was a randomized trial of tandem colonoscopies. The study was performed at the Academic Medical Center in Amsterdam. One hundred patients underwent colonoscopy with ETMI. Each colonic segment was examined twice for polyps, once with HRE and once with AFI, in random order per patient. All detected polyps were assessed with NBI for pit pattern and with AFI for color, and subsequently removed. Histopathology served as the gold standard for diagnosis. The main outcome measures of this study were adenoma miss-rates of AFI and HRE, and diagnostic accuracy of NBI and AFI for differentiating adenomas from nonneoplastic polyps. Among 50 patients examined with AFI first, 32 adenomas were detected initially. Subsequent inspection with HRE identified 8 additional adenomas. Among 50 patients examined with HRE first, 35 adenomas were detected initially. Successive AFI yielded 14 additional adenomas. The adenoma miss-rates of AFI and HRE therefore were 20% and 29%, respectively (P = .351). The sensitivity, specificity, and overall accuracy of NBI for differentiation were 90%, 70%, and 79%, respectively; corresponding figures for AFI were 99%, 35%, and 63%, respectively. The overall adenoma miss-rate was 25%; AFI did not significantly reduce the adenoma miss-rate compared with HRE. Both NBI and AFI had a disappointing diagnostic accuracy for polyp differentiation, although AFI had a high sensitivity.

  6. Model-based iterative reconstruction in low-dose CT colonography-feasibility study in 65 patients for symptomatic investigation.

    PubMed

    Vardhanabhuti, Varut; James, Julia; Nensey, Rehaan; Hyde, Christopher; Roobottom, Carl

    2015-05-01

    To compare image quality on computed tomographic colonography (CTC) acquired at standard dose (STD) and low dose (LD) using filtered-back projection, adaptive statistical iterative reconstruction, and model-based iterative reconstruction (MBIR) techniques. A total of 65 symptomatic patients were prospectively enrolled for the study and underwent STD and LD CTC with filtered-back projection, adaptive statistical iterative reconstruction, and MBIR to allow direct per-patient comparison. Objective image noise, subjective image analyses, and polyp detection were assessed. Objective image noise analysis demonstrates significant noise reduction using MBIR technique (P < .05) despite being acquired at lower doses. Subjective image analyses were superior for LD MBIR in all parameters except visibility of extracolonic lesions (two-dimensional) and visibility of colonic wall (three-dimensional) where there were no significant differences. There was no significant difference in polyp detection rates (P > .05). Doses: LD (dose-length product, 257.7), STD (dose-length product, 483.6). LD MBIR CTC objectively shows improved image noise using parameters in our study. Subjectively, image quality is maintained. Polyp detection shows no significant difference but because of small numbers needs further validation. Average dose reduction of 47% can be achieved. This study confirms feasibility of using MBIR in this context of CTC in symptomatic population. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  7. High resolution colonoscopy in a bowel cancer screening program improves polyp detection

    PubMed Central

    Banks, Matthew R; Haidry, Rehan; Butt, M Adil; Whitley, Lisa; Stein, Judith; Langmead, Louise; Bloom, Stuart L; O’Bichere, Austin; McCartney, Sara; Basherdas, Kalpesh; Rodriguez-Justo, Manuel; Lovat, Laurence B

    2011-01-01

    AIM: To compare high resolution colonoscopy (Olympus Lucera) with a megapixel high resolution system (Pentax HiLine) as an in-service evaluation. METHODS: Polyp detection rates and measures of performance were collected for 269 colonoscopy procedures. Five colonoscopists conducted the study over a three month period, as part of the United Kingdom bowel cancer screening program. RESULTS:There were no differences in procedure duration (χ2 P = 0.98), caecal intubation rates (χ2 P = 0.67), or depth of sedation (χ2 P = 0.64). Mild discomfort was more common in the Pentax group (χ2 P = 0.036). Adenoma detection rate was significantly higher in the Pentax group (χ2 test for trend P = 0.01). Most of the extra polyps detected were flat or sessile adenomas. CONCLUSION: Megapixel definition colonoscopes improve adenoma detection without compromising other measures of endoscope performance. Increased polyp detection rates may improve future outcomes in bowel cancer screening programs. PMID:22090787

  8. Virtual gastrointestinal colonoscopy in combination with large bowel endoscopy: Clinical application

    PubMed Central

    He, Qing; Rao, Ting; Guan, Yong-Song

    2014-01-01

    Although colorectal cancer (CRC) has no longer been the leading cancer killer worldwide for years with the exponential development in computed tomography (CT) or magnetic resonance imaging, and positron emission tomography/CT as well as virtual colonoscopy for early detection, the CRC related mortality is still high. The objective of CRC screening is to reduce the burden of CRC and thereby the morbidity and mortality rates of the disease. It is believed that this goal can be achieved by regularly screening the average-risk population, enabling the detection of cancer at early, curable stages, and polyps before they become cancerous. Large-scale screening with multimodality imaging approaches plays an important role in reaching that goal to detect polyps, Crohn’s disease, ulcerative colitis and CRC in early stage. This article reviews kinds of presentative imaging procedures for various screening options and updates detecting, staging and re-staging of CRC patients for determining the optimal therapeutic method and forecasting the risk of CRC recurrence and the overall prognosis. The combination use of virtual colonoscopy and conventional endoscopy, advantages and limitations of these modalities are also discussed. PMID:25320519

  9. Clinicopathologic review of polyps biopsied at colonoscopy in Lagos, Nigeria.

    PubMed

    Oluyemi, Aderemi; Awolola, Nicholas; Oyedeji, Olufemi

    2016-01-01

    Colorectal polyps are known precursors of colorectal cancers. The increase in utilization of colonoscopy in Nigeria has meant a rise in the recently reported incidence of these lesions. The aim of this study is to evaluate the clinicopathological profile of colorectal polyps biopsied during the inaugural 12 month period of colonoscopy from a private endoscopy suite in Nigeria. This is a retrospective review of all the clients who had polyps diagnosed at colonoscopy over a 12 month period (August 2014 -July 2015) at a private endoscopy suite in Lagos, Nigeria. This analysis of prospectively collected data was performed using clinical information from the endoscopy logs and pathology database system of a private endoscopy suite based in Lagos, Nigeria. A total of 125 colonoscopies were carried out over the stated period. Of these, 14 individuals had a total of 18 polyps- 4 clients (28.6% of the persons with polyps) had two polyps each. The polyp detection rate was 11.2% while the polyp per colonoscopy rate was 14.4%. Of these clients, males were 10 in number; giving a male to female ratio of 2.5:1. Their ages ranged from 37 to 77 years (mean= 57.3 years). The presenting complaint at colonoscopy was hematochezia in 11 (78.6%), new onset constipation in 2 (14.2%) and peri-anal pain in 1 patient (7.1%). The polyps were distributed as follows; 2 (11.1%) in the ascending colon, 1 (5.6%) each in the transverse and descending colons, 8 (44.4%) in the sigmoid colon, 6(33.3%) located in the rectum. Hence, there was left sided (15 of 18= 83.3%) preponderance. Pathologically, tubular (adenomatous) polyp with or without low grade dysplastic changes was diagnosed in 6 of the 18 polyps (giving an adenoma detection rate of 4.8%), 4 (22.2%) were inflammatory polyps, 1 (5.6%) was malignant and another had the rare inflammatory fibroid polyp. Five (27.8%) of the specimens were reported as non-specific colitis. The study supports the present wisdom that polyps are clearly less prevalent in our environment when compared to the Western world. The increased prevalence with advancing age, in male subjects and of left sided lesions, is also in keeping with previous results from our environment. A case is also advanced for the increased deployment of endoscopy as a tool for the detection of these polyps and ultimately, the reduction of colorectal cancer in our population.

  10. Cost-effectiveness of colorectal cancer screening with computed tomography colonography according to a polyp size threshold for polypectomy.

    PubMed

    Heresbach, Denis; Chauvin, Pauline; Hess-Migliorretti, Aurélie; Riou, Françoise; Grolier, Jacques; Josselin, Jean-Michel

    2010-06-01

    Computed tomography colonography (CTC) has an acceptable accuracy in detecting colonic lesions, especially for polyps at least 6 mm. The aim of this analysis is to determine the cost-effectiveness of population-based screening for colorectal cancer (CRC) using CTC with a polyp size threshold. The cost-effectiveness ratios of CTC performed at 50, 60 and 70 years old, without (PL strategy) or with (TS strategy) polyp size threshold were compared using a Markov process. Incremental cost-effectiveness ratios (ICER) were calculated per life-years gained (LYG) for a time horizon of 30 years. The ICER of PL and TS strategies were 12 042 and 2765 euro/LYG associated to CRC prevention rates of 37.9 and 36.5%. The ICER of PL and TS strategies dropped to 9687 and 1857 euro/LYG when advanced adenoma (AA) prevalence increased from 6.9 to 8.6% for male participants and 3.8-4.9% for female participants or to 9482 and 2067 euro/LYG when adenoma and AA annual recurrence rates dropped to 3.2 and 0.25%. The ICER for PL and TS strategies decreased to 7947 and 954 euro/LYG or when only two CTC were performed at 50 and 60-years-old. Conversely, the ICER did not significantly change when varying population participation rate or accuracy of CTC. CTC with a 6 mm threshold for polypectomy is associated to a substantial cost reduction without significant loss of efficacy. Cost-effectiveness depends more on the AA prevalence or transition rate to CRC than on CTC accuracy or screening compliance.

  11. How does the serrated polyp pathway alter CRC screening and surveillance?

    PubMed

    Kahi, Charles J

    2015-03-01

    Screening and surveillance for colorectal cancer (CRC) reduces mortality through the detection of early-stage adenocarcinoma, and more importantly the detection and removal of premalignant polyps. While adenomas have historically been considered the most common and screening-relevant precursor lesions, there is accumulating evidence showing that the serrated pathway is an important contributor to CRC, and a disproportionate contributor to interval or postcolonoscopy CRC, particularly in the proximal colon. The serrated pathway is characterized by mutations in the BRAF gene, high levels of methylation of promoter CpG islands (CIMP-high), and the sessile serrated adenoma/polyp (SSA/P) is the most important precursor lesion. The study of serrated polyps has been complicated by evolving nomenclature, substantial variation among pathologists in the identification of SSA/Ps, high variability in endoscopic detection rates, and uncertainty regarding the relation to synchronous and metachronous colonic neoplasia. This paper presents an overview of the serrated polyp pathway and discusses its clinical implications including its impact on CRC screening.

  12. A novel summary report of colonoscopy: timeline visualization providing meaningful colonoscopy video information.

    PubMed

    Cho, Minwoo; Kim, Jee Hyun; Kong, Hyoun Joong; Hong, Kyoung Sup; Kim, Sungwan

    2018-05-01

    The colonoscopy adenoma detection rate depends largely on physician experience and skill, and overlooked colorectal adenomas could develop into cancer. This study assessed a system that detects polyps and summarizes meaningful information from colonoscopy videos. One hundred thirteen consecutive patients had colonoscopy videos prospectively recorded at the Seoul National University Hospital. Informative video frames were extracted using a MATLAB support vector machine (SVM) model and classified as bleeding, polypectomy, tool, residue, thin wrinkle, folded wrinkle, or common. Thin wrinkle, folded wrinkle, and common frames were reanalyzed using SVM for polyp detection. The SVM model was applied hierarchically for effective classification and optimization of the SVM. The mean classification accuracy according to type was over 93%; sensitivity was over 87%. The mean sensitivity for polyp detection was 82.1%, and the positive predicted value (PPV) was 39.3%. Polyps detected using the system were larger (6.3 ± 6.4 vs. 4.9 ± 2.5 mm; P = 0.003) with a more pedunculated morphology (Yamada type III, 10.2 vs. 0%; P < 0.001; Yamada type IV, 2.8 vs. 0%; P < 0.001) than polyps missed by the system. There were no statistically significant differences in polyp distribution or histology between the groups. Informative frames and suspected polyps were presented on a timeline. This summary was evaluated using the system usability scale questionnaire; 89.3% of participants expressed positive opinions. We developed and verified a system to extract meaningful information from colonoscopy videos. Although further improvement and validation of the system is needed, the proposed system is useful for physicians and patients.

  13. Endotics system vs colonoscopy for the detection of polyps

    PubMed Central

    Tumino, Emanuele; Sacco, Rodolfo; Bertini, Marco; Bertoni, Michele; Parisi, Giuseppe; Capria, Alfonso

    2010-01-01

    AIM: To compare the endotics system (ES), a set of new medical equipment for diagnostic colonoscopy, with video-colonoscopy in the detection of polyps. METHODS: Patients with clinical or familial risk of colonic polyps/carcinomas were eligible for this study. After a standard colonic cleaning, detection of polyps by the ES and by video-colonoscopy was performed in each patient on the same day. In each single patient, the assessment of the presence of polyps was performed by two independent endoscopists, who were randomly assigned to evaluate, in a blind fashion, the presence of polyps either by ES or by standard colonoscopy. The frequency of successful procedures (i.e. reaching to the cecum), the time for endoscopy, and the need for sedation were recorded. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the ES were also calculated. RESULTS: A total of 71 patients (40 men, mean age 51.9 ± 12.0 years) were enrolled. The cecum was reached in 81.6% of ES examinations and in 94.3% of colonoscopies (P = 0.03). The average time of endoscopy was 45.1 ± 18.5 and 23.7 ± 7.2 min for the ES and traditional colonoscopy, respectively (P < 0.0001). No patient required sedation during ES examination, compared with 19.7% of patients undergoing colonoscopy (P < 0.0001). The sensitivity and specificity of ES for detecting polyps were 93.3% (95% CI: 68-98) and 100% (95% CI: 76.8-100), respectively. PPV was 100% (95% CI: 76.8-100) and NPV was 97.7% (95% CI: 88-99.9). CONCLUSION: The ES allows the visualization of the entire colonic mucosa in most patients, with good sensitivity/specificity for the detection of lesions and without requiring sedation. PMID:21086563

  14. The frequency of early colorectal cancer derived from sessile serrated adenoma/polyps among 1858 serrated polyps from a single institution.

    PubMed

    Chino, A; Yamamoto, N; Kato, Y; Morishige, K; Ishikawa, H; Kishihara, T; Fujisaki, J; Ishikawa, Y; Tamegai, Y; Igarashi, M

    2016-02-01

    Sessile serrated adenoma/polyps (SSAPs) are suspected to have a high malignant potential, although few reports have evaluated the incidence of carcinomas derived from SSAPs using the new classification for serrated polyps (SPs). The aim of study was to compare the frequency of cancer coexisting with the various SP subtypes including mixed polyps (MIXs) and conventional adenomas (CADs). A total of 18,667 CADs were identified between April 2005 and December 2011, and 1858 SPs (re-classified as SSAP, hyperplastic polyp (HP), traditional serrated adenoma (TSA), or MIX) were removed via snare polypectomy, endoscopic mucosal resection, or endoscopic sub-mucosal dissection. Among 1160 HP lesions, 1 (0.1%) coexisting sub-mucosal invasive carcinoma (T1) was detected. Among 430 SSAP lesions, 3 (0.7%) high-grade dysplasia (HGD/Tis) and 1 (0.2%) T1 were detected. All of the lesions were detected in the proximal colon, with a mean tumor diameter of 18 mm (SD 9 mm). Among 212 TSA lesions, 3 (1%) HGD/Tis were detected but no T1 cancer. Among 56 MIX lesions, 9 (16%) HGD/Tis and 1 (2%) T1 cancers were detected, and among 18,677 CAD lesions, 964 (5%) HGD/Tis and 166 (1%) T1 cancers were identified. Among the resected lesions that were detected during endoscopic examination, a smaller proportion (1%) of SSAPs harbored HGD or coexisting cancer, compared to CAD or MIX lesions. Therefore, more attention should be paid to accurately identifying lesions endoscopically for intentional resection and the surveillance of each SP subtype.

  15. Colorectal cancer screening with virtual colonoscopy

    NASA Astrophysics Data System (ADS)

    Ge, Yaorong; Vining, David J.; Ahn, David K.; Stelts, David R.

    1999-05-01

    Early detection and removal of colorectal polyps have been proven to reduce mortality from colorectal carcinoma (CRC), the second leading cause of cancer deaths in the United States. Unfortunately, traditional techniques for CRC examination (i.e., barium enema, sigmoidoscopy, and colonoscopy) are unsuitable for mass screening because of either low accuracy or poor public acceptance, costs, and risks. Virtual colonoscopy (VC) is a minimally invasive alternative that is based on tomographic scanning of the colon. After a patient's bowel is optimally cleansed and distended with gas, a fast tomographic scan, typically helical computed tomography (CT), of the abdomen is performed during a single breath-hold acquisition. Two-dimensional (2D) slices and three-dimensional (3D) rendered views of the colon lumen generated from the tomographic data are then examined for colorectal polyps. Recent clinical studies conducted at several institutions including ours have shown great potential for this technology to be an effective CRC screening tool. In this paper, we describe new methods to improve bowel preparation, colon lumen visualization, colon segmentation, and polyp detection. Our initial results show that VC with the new bowel preparation and imaging protocol is capable of achieving accuracy comparable to conventional colonoscopy and our new algorithms for image analysis contribute to increased accuracy and efficiency in VC examinations.

  16. Relation between obesity and adenomatous polyps of the large bowel.

    PubMed

    Sato, Yumi; Nozaki, Ryoichi; Yamada, Kazutaka; Takano, Masahiro; Haruma, Ken

    2009-07-01

    We compared the prevalence of colorectal adenoma (polyps) in men and women and examined the role of body mass index (BMI) on polyp risk according to patient age and gender. The risk of developing colorectal polyps was studied in 15 380 subjects (7155 men and 8225 women) who underwent colonoscopy for the first time from April 1998 to March 2006 at our 'Human Dry Dock', which is the check-up service provided in Japan. Eligible subjects were 20-86 years old (mean age +/- SD, 47.3 +/- 8.5) and were free of invasive cancer, hyperplastic polyps and familial polyposis. Polyps were found in 1590 subjects (1062 men and 528 women). The odds ratio (OR) of detection of polyps in relation to obesity was determined in all cases by multivariate logistic regression analysis after making an adjustment for gender and age. The OR of polyp detection in obese subjects (BMI >or= 25) versus non-obese subjects (BMI < 25, OR = 1) was 1.34 (P < 0.001) in men and 1.13 (P = 0.26) in women. As the BMI increased in increments of one, the OR in men increased significantly to 1.01 (P < 0.001), whereas the OR in women was unchanged at 1.00 (P = 0.23), which was without significance. We conclude that obesity in men is a risk factor for the development of polyps. These results must be confirmed by additional epidemiological studies.

  17. Computer-aided diagnosis of colorectal polyp histology by using a real-time image recognition system and narrow-band imaging magnifying colonoscopy.

    PubMed

    Kominami, Yoko; Yoshida, Shigeto; Tanaka, Shinji; Sanomura, Yoji; Hirakawa, Tsubasa; Raytchev, Bisser; Tamaki, Toru; Koide, Tetsusi; Kaneda, Kazufumi; Chayama, Kazuaki

    2016-03-01

    It is necessary to establish cost-effective examinations and treatments for diminutive colorectal tumors that consider the treatment risk and surveillance interval after treatment. The Preservation and Incorporation of Valuable Endoscopic Innovations (PIVI) committee of the American Society for Gastrointestinal Endoscopy published a statement recommending the establishment of endoscopic techniques that practice the resect and discard strategy. The aims of this study were to evaluate whether our newly developed real-time image recognition system can predict histologic diagnoses of colorectal lesions depicted on narrow-band imaging and to satisfy some problems with the PIVI recommendations. We enrolled 41 patients who had undergone endoscopic resection of 118 colorectal lesions (45 nonneoplastic lesions and 73 neoplastic lesions). We compared the results of real-time image recognition system analysis with that of narrow-band imaging diagnosis and evaluated the correlation between image analysis and the pathological results. Concordance between the endoscopic diagnosis and diagnosis by a real-time image recognition system with a support vector machine output value was 97.5% (115/118). Accuracy between the histologic findings of diminutive colorectal lesions (polyps) and diagnosis by a real-time image recognition system with a support vector machine output value was 93.2% (sensitivity, 93.0%; specificity, 93.3%; positive predictive value (PPV), 93.0%; and negative predictive value, 93.3%). Although further investigation is necessary to establish our computer-aided diagnosis system, this real-time image recognition system may satisfy the PIVI recommendations and be useful for predicting the histology of colorectal tumors. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  18. Pathogenesis and Management of Serrated Polyps: Current Status and Future Directions

    PubMed Central

    Anderson, Joseph C.

    2014-01-01

    Hyperplastic or serrated polyps were once believed to have little to no clinical significance. A subset of these polyps are now considered to be precursors to colorectal cancers (CRC) in the serrated pathway that may account for at least 15% of all tumors. The serrated pathway is distinct from the two other CRC pathways and involves an epigenetic hypermethylation mechanism of CpG islands within promoter regions of tumor suppressor genes. This process results in the formation of CpG island methylator phenotype tumors. Serrated polyps are divided into hyperplastic polyps, sessile serrated adenomas/polyps (SSA/Ps), and traditional serrated adenomas (TSAs). The SSA/P and the TSA have the potential for dysplasia and subsequent malignant transformation. The SSA/Ps are more common and are more likely to be flat than TSAs. Their flat morphology may make them difficult to detect and thus explain the variation in detection rates among endoscopists. Challenges for endoscopists also include the difficulty in pathological interpretation as well surveillance of these lesions. Furthermore, serrated polyps may be inadequately resected by endoscopists. Thus, it is not surprising that the serrated pathway has been linked with interval cancers. This review will provide the physician or clinician with the knowledge to manage patients with serrated polyps. PMID:25368744

  19. The Effects of Size and Type of Vocal Fold Polyp on Some Acoustic Voice Parameters.

    PubMed

    Akbari, Elaheh; Seifpanahi, Sadegh; Ghorbani, Ali; Izadi, Farzad; Torabinezhad, Farhad

    2018-03-01

    Vocal abuse and misuse would result in vocal fold polyp. Certain features define the extent of vocal folds polyp effects on voice acoustic parameters. The present study aimed to define the effects of polyp size on acoustic voice parameters, and compare these parameters in hemorrhagic and non-hemorrhagic polyps. In the present retrospective study, 28 individuals with hemorrhagic or non-hemorrhagic polyps of the true vocal folds were recruited to investigate acoustic voice parameters of vowel/ æ/ computed by the Praat software. The data were analyzed using the SPSS software, version 17.0. According to the type and size of polyps, mean acoustic differences and correlations were analyzed by the statistical t test and Pearson correlation test, respectively; with significance level below 0.05. The results indicated that jitter and the harmonics-to-noise ratio had a significant positive and negative correlation with the polyp size (P=0.01), respectively. In addition, both mentioned parameters were significantly different between the two types of the investigated polyps. Both the type and size of polyps have effects on acoustic voice characteristics. In the present study, a novel method to measure polyp size was introduced. Further confirmation of this method as a tool to compare polyp sizes requires additional investigations.

  20. The Effects of Size and Type of Vocal Fold Polyp on Some Acoustic Voice Parameters

    PubMed Central

    Akbari, Elaheh; Seifpanahi, Sadegh; Ghorbani, Ali; Izadi, Farzad; Torabinezhad, Farhad

    2018-01-01

    Background Vocal abuse and misuse would result in vocal fold polyp. Certain features define the extent of vocal folds polyp effects on voice acoustic parameters. The present study aimed to define the effects of polyp size on acoustic voice parameters, and compare these parameters in hemorrhagic and non-hemorrhagic polyps. Methods In the present retrospective study, 28 individuals with hemorrhagic or non-hemorrhagic polyps of the true vocal folds were recruited to investigate acoustic voice parameters of vowel/ æ/ computed by the Praat software. The data were analyzed using the SPSS software, version 17.0. According to the type and size of polyps, mean acoustic differences and correlations were analyzed by the statistical t test and Pearson correlation test, respectively; with significance level below 0.05. Results The results indicated that jitter and the harmonics-to-noise ratio had a significant positive and negative correlation with the polyp size (P=0.01), respectively. In addition, both mentioned parameters were significantly different between the two types of the investigated polyps. Conclusion Both the type and size of polyps have effects on acoustic voice characteristics. In the present study, a novel method to measure polyp size was introduced. Further confirmation of this method as a tool to compare polyp sizes requires additional investigations. PMID:29749984

  1. Influence of Computer-Aided Detection on Performance of Screening Mammography

    PubMed Central

    Fenton, Joshua J.; Taplin, Stephen H.; Carney, Patricia A.; Abraham, Linn; Sickles, Edward A.; D'Orsi, Carl; Berns, Eric A.; Cutter, Gary; Hendrick, R. Edward; Barlow, William E.; Elmore, Joann G.

    2011-01-01

    Background Computer-aided detection identifies suspicious findings on mammograms to assist radiologists. Since the Food and Drug Administration approved the technology in 1998, it has been disseminated into practice, but its effect on the accuracy of interpretation is unclear. Methods We determined the association between the use of computer-aided detection at mammography facilities and the performance of screening mammography from 1998 through 2002 at 43 facilities in three states. We had complete data for 222,135 women (a total of 429,345 mammograms), including 2351 women who received a diagnosis of breast cancer within 1 year after screening. We calculated the specificity, sensitivity, and positive predictive value of screening mammography with and without computer-aided detection, as well as the rates of biopsy and breast-cancer detection and the overall accuracy, measured as the area under the receiver-operating-characteristic (ROC) curve. Results Seven facilities (16%) implemented computer-aided detection during the study period. Diagnostic specificity decreased from 90.2% before implementation to 87.2% after implementation (P<0.001), the positive predictive value decreased from 4.1% to 3.2% (P = 0.01), and the rate of biopsy increased by 19.7% (P<0.001). The increase in sensitivity from 80.4% before implementation of computer-aided detection to 84.0% after implementation was not significant (P = 0.32). The change in the cancer-detection rate (including invasive breast cancers and ductal carcinomas in situ) was not significant (4.15 cases per 1000 screening mammograms before implementation and 4.20 cases after implementation, P = 0.90). Analyses of data from all 43 facilities showed that the use of computer-aided detection was associated with significantly lower overall accuracy than was nonuse (area under the ROC curve, 0.871 vs. 0.919; P = 0.005). Conclusions The use of computer-aided detection is associated with reduced accuracy of interpretation of screening mammograms. The increased rate of biopsy with the use of computer-aided detection is not clearly associated with improved detection of invasive breast cancer. PMID:17409321

  2. Ultrasound diagnosis of gallbladder polyps.

    PubMed

    Tomić, Dragan V; Marković, Aleksandra R Pavlović; Alempijević, Tamara M; Davidović, Dragana B; Prsić, Daliborka R; Vucković, Maja S

    2011-01-01

    The most frequent benign gallbladder polyps are cholesterol polyps. Next in frequency were adenomas, which may have malignant potential. The aim of this study was to assess the possibility of ultrasonography in the diagnosis and differential diagnosis of cholesterol polyps compared to adenomas. Patients were examined during the period from October 2006. to December 2008. In Department of Ultrasound, Clinic for Gastroenterology and Hepatology, Belgrade. The group of 54 patients analyzed consisted of 30 women (56%) and 24 men (44%). Most (59%) had solitary polyps. In 92.6% of patients the size of polyps was below 10 mm. 74% of respondents were over 50 years. Ultrasonography is the method of choice and gold standard in diagnosis of gallbladder polyps. Based on echoic properties cholesterol polyps can not be distinguished from adenomas. Malignant alteration of polyps also could not be detected. Appropriate ultrasonographic characteristics such as size of polyps, appearance of a broad base that sits on the wall, concomitant lithiasis findings and patient age may be indicative for malignancy.

  3. Computer assisted optical biopsy for colorectal polyps

    NASA Astrophysics Data System (ADS)

    Navarro-Avila, Fernando J.; Saint-Hill-Febles, Yadira; Renner, Janis; Klare, Peter; von Delius, Stefan; Navab, Nassir; Mateus, Diana

    2017-03-01

    We propose a method for computer-assisted optical biopsy for colorectal polyps, with the final goal of assisting the medical expert during the colonoscopy. In particular, we target the problem of automatic classification of polyp images in two classes: adenomatous vs non-adenoma. Our approach is based on recent advancements in convolutional neural networks (CNN) for image representation. In the paper, we describe and compare four different methodologies to address the binary classification task: a baseline with classical features and a Random Forest classifier, two methods based on features obtained from a pre-trained network, and finally, the end-to-end training of a CNN. With the pre-trained network, we show the feasibility of transferring a feature extraction mechanism trained on millions of natural images, to the task of classifying adenomatous polyps. We then demonstrate further performance improvements when training the CNN for our specific classification task. In our study, 776 polyp images were acquired and histologically analyzed after polyp resection. We report a performance increase of the CNN-based approaches with respect to both, the conventional engineered features and to a state-of-the-art method based on videos and 3D shape features.

  4. [Research of conjugated bile acids in gallbladder bile of patients with polypoid lesions of gallbladder].

    PubMed

    Ge, Chunlin; Sun, Tao; Meng, Jingjuan; Wang, Kun; Huang, Peng

    2014-02-01

    To investigate the difference in conjugated bile acids in the gallbladder bile between gallbladder cholesterol polyps and adenomatous polyps patients, and screen the differential diagnosis-markers for polypoid lesions of gallbladder (PLG). From January to June 2013, the 20 cholesterol polyps patients, 10 adenomatous polyps patients and 10 patients without gallbladder diseases were enrolled. High performance liquid chromatography assay with ultraviolet detection was used to test 8 conjugated bile acids in gallbladder bile. The 8 conjugated bile acids were completely analyzed in 10 minutes, and the assay was liner in the range 8-500 µg/ml. The correlation coeffients for linear regression was from 0.9996-0.9999 and the detection limits ranged from 3.90-7.81 µg/ml. The level of taurocholic acid (TCA) in adenomatous polyps group ((75 ± 51) µg/ml) was significantly lower than that in the cholesterol polyps ((228 ± 206) µg/ml, q = 3.120, P = 0.014) and control groups ((104 ± 40) µg/ml, q = 2.950, P = 0.027). The level of taurochenodeoxycholic acid (TCDCA) in cholesterol polyps group ((604 ± 444) µg/ml) was significantly higher than that in the adenomatous polyps ((310 ± 182) µg/ml, q = 2.560, P = 0.048) and control groups ((308 ± 21) µg/ml, q = 2.970, P = 0.023). The levels of TCA and TCDCA in the gallbladder biles in cholesterol polyps patients were higher than those in adenomatous polyps patients, which may be the differential diagnosis-markers for PLG.

  5. Didactic training vs. computer-based self-learning in the prediction of diminutive colon polyp histology by trainees: a randomized controlled study.

    PubMed

    Khan, Taimur; Cinnor, Birtukan; Gupta, Neil; Hosford, Lindsay; Bansal, Ajay; Olyaee, Mojtaba S; Wani, Sachin; Rastogi, Amit

    2017-12-01

    Background and study aim  Experts can accurately predict diminutive polyp histology, but the ideal method to train nonexperts is not known. The aim of the study was to compare accuracy in diminutive polyp histology characterization using narrow-band imaging (NBI) between participants undergoing classroom didactic training vs. computer-based self-learning. Participants and methods  Trainees at two institutions were randomized to classroom didactic training or computer-based self-learning. In didactic training, experienced endoscopists reviewed a presentation on NBI patterns for adenomatous and hyperplastic polyps and 40 NBI videos, along with interactive discussion. The self-learning group reviewed the same presentation of 40 teaching videos independently, without interactive discussion. A total of 40 testing videos of diminutive polyps under NBI were then evaluated by both groups. Performance characteristics were calculated by comparing predicted and actual histology. Fisher's exact test was used and P  < 0.05 was considered significant. Results  A total of 17 trainees participated (8 didactic training and 9 self-learning). A larger proportion of polyps were diagnosed with high confidence in the classroom group (66.5 % vs. 50.8 %; P  < 0.01), although sensitivity (86.9 % vs. 95.0 %) and accuracy (85.7 % vs. 93.9 %) of high-confidence predictions were higher in the self-learning group. However, there was no difference in overall accuracy of histology characterization (83.4 % vs. 87.2 %; P  = 0.19). Similar results were noted when comparing sensitivity and specificity between the groups. Conclusion  The self-learning group showed results on a par with or, for high-confidence predictions, even slightly superior to classroom didactic training for predicting diminutive polyp histology. This approach can help in widespread training and clinical implementation of real-time polyp histology characterization. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Dual modality virtual colonoscopy workstation: design, implementation, and preliminary evaluation

    NASA Astrophysics Data System (ADS)

    Chen, Dongqing; Meissner, Michael

    2006-03-01

    The aim of this study is to develop a virtual colonoscopy (VC) workstation that supports both CT (computed tomography) and MR (magnetic resonance) imaging procedures. The workflow should be optimized and be able to take advantage of both image modalities. The technological break through is at the real-time volume rendering of spatial-intensity-inhomogeneous MR images to achieve high quality 3D endoluminal view. VC aims at visualizing CT or MR tomography images for detection of colonic polyp and lesion. It is also called as CT/MR colonography based on the imaging modality that is employed. The published results of large scale clinical trial demonstrated more than 90% of sensitivity on polyp detection for certain CT colonography (CTC) workstation. A drawback of the CT colonoscopy is the radiation exposure. MR colonography (MRC) is free from the X-ray radiation. It achieved almost 100% specificity for polyp detection in published trials. The better tissue contrast in MR image allows the accurate diagnosis of inflammatory bowel disease also, which is usually difficult in CTC. At present, most of the VC workstations are designed for CT examination. They are not able to display multi-sequence MR series concurrently in a single application. The automatic correlation between 2D and 3D view is not available due to the difficulty of 3D model building for MR images. This study aims at enhancing a commercial VC product that was successfully used for CTC to equally support dark-lumen protocol MR procedure also.

  7. Colorectal cancer detection and screening.

    PubMed

    Gruber, M; Lance, P

    1998-01-01

    Colon cancer is a leading cause of death in the United States and is estimated to cause 56,500 deaths during 1998. Most cancers evolve from adenomatous polyps. Screening asymptomatic average-risk individuals is recommended to reduce colorectal cancer mortality by detection and removal of adenomatous polyps.

  8. An evidence-based treatment algorithm for colorectal polyp cancers: results from the Scottish Screen-detected Polyp Cancer Study (SSPoCS).

    PubMed

    Richards, C H; Ventham, N T; Mansouri, D; Wilson, M; Ramsay, G; Mackay, C D; Parnaby, C N; Smith, D; On, J; Speake, D; McFarlane, G; Neo, Y N; Aitken, E; Forrest, C; Knight, K; McKay, A; Nair, H; Mulholland, C; Robertson, J H; Carey, F A; Steele, Rjc

    2018-02-01

    Colorectal polyp cancers present clinicians with a treatment dilemma. Decisions regarding whether to offer segmental resection or endoscopic surveillance are often taken without reference to good quality evidence. The aim of this study was to develop a treatment algorithm for patients with screen-detected polyp cancers. This national cohort study included all patients with a polyp cancer identified through the Scottish Bowel Screening Programme between 2000 and 2012. Multivariate regression analysis was used to assess the impact of clinical, endoscopic and pathological variables on the rate of adverse events (residual tumour in patients undergoing segmental resection or cancer-related death or disease recurrence in any patient). These data were used to develop a clinically relevant treatment algorithm. 485 patients with polyp cancers were included. 186/485 (38%) underwent segmental resection and residual tumour was identified in 41/186 (22%). The only factor associated with an increased risk of residual tumour in the bowel wall was incomplete excision of the original polyp (OR 5.61, p=0.001), while only lymphovascular invasion was associated with an increased risk of lymph node metastases (OR 5.95, p=0.002). When patients undergoing segmental resection or endoscopic surveillance were considered together, the risk of adverse events was significantly higher in patients with incomplete excision (OR 10.23, p<0.001) or lymphovascular invasion (OR 2.65, p=0.023). A policy of surveillance is adequate for the majority of patients with screen-detected colorectal polyp cancers. Consideration of segmental resection should be reserved for those with incomplete excision or evidence of lymphovascular invasion. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  9. Higher Prevalence of Endometrial Polyps in Infertile Patients with Endometriosis.

    PubMed

    Zhang, Ya-Nan; Zhang, You-Sheng; Yu, Qian; Guo, Zi-Zhen; Ma, Jin-Long; Yan, Lei

    2018-06-07

    To study whether infertile patients with endometriosis have a higher prevalence of endometrial polyps, and to clarify the characteristics of the pathology of combined polyps. Infertile patients who had undergone both hysteroscopy and laparoscopy in Reproductive Hospital Affiliated with Shandong University from January 2014 to May 2017 were enrolled. Patients with and without endometriosis, diagnosed by laparoscopy, were staged and included in the study group and control group, respectively, and the prevalence of polyps was compared. The pathological types of endometrial polyps were analyzed. A total of 414 cases were enrolled in the study group and 3,048 cases in the control group; polyps were diagnosed, with endoscopy, in 1,107 patients. Endometrial polyps were detected by hysteroscopy in 47.83% of the endometriosis group and 29.82% of the control group. The prevalence of endometrial polyps was significantly higher in the endometriosis group than in the control group (p < 0.001) but not significantly different between stages of endometriosis (p = 0.580). The pathological diagnosis included 899 endometrial polyps and 208 polypoid hyperplasia; 66.5% of endometrial polyps were combined with simple hyperplasia. The infertile patients with endometriosis had a higher prevalence of endometrial polyps, and those polyps are often combined with simple hyperplasia. © 2018 S. Karger AG, Basel.

  10. A new fractional order derivative based active contour model for colon wall segmentation

    NASA Astrophysics Data System (ADS)

    Chen, Bo; Li, Lihong C.; Wang, Huafeng; Wei, Xinzhou; Huang, Shan; Chen, Wensheng; Liang, Zhengrong

    2018-02-01

    Segmentation of colon wall plays an important role in advancing computed tomographic colonography (CTC) toward a screening modality. Due to the low contrast of CT attenuation around colon wall, accurate segmentation of the boundary of both inner and outer wall is very challenging. In this paper, based on the geodesic active contour model, we develop a new model for colon wall segmentation. First, tagged materials in CTC images were automatically removed via a partial volume (PV) based electronic colon cleansing (ECC) strategy. We then present a new fractional order derivative based active contour model to segment the volumetric colon wall from the cleansed CTC images. In this model, the regionbased Chan-Vese model is incorporated as an energy term to the whole model so that not only edge/gradient information but also region/volume information is taken into account in the segmentation process. Furthermore, a fractional order differentiation derivative energy term is also developed in the new model to preserve the low frequency information and improve the noise immunity of the new segmentation model. The proposed colon wall segmentation approach was validated on 16 patient CTC scans. Experimental results indicate that the present scheme is very promising towards automatically segmenting colon wall, thus facilitating computer aided detection of initial colonic polyp candidates via CTC.

  11. Optical diagnosis of small colorectal polyps at routine colonoscopy (Detect InSpect ChAracterise Resect and Discard; DISCARD trial): a prospective cohort study.

    PubMed

    Ignjatovic, Ana; East, James E; Suzuki, Noriko; Vance, Margaret; Guenther, Thomas; Saunders, Brian P

    2009-12-01

    Accurate optical diagnosis of small (<10 mm) colorectal polyps in vivo, without formal histopathology, could make colonoscopy more efficient and cost effective. The aim of this study was to assess whether optical diagnosis of small polyps is feasible and safe in routine clinical practice. Consecutive patients with a positive faecal occult blood test or previous adenomas undergoing surveillance at St Mark's Hospital (London, UK), from June 19, 2008, to June 16, 2009, were included in this prospective study. Four colonoscopists with different levels of experience predicted polyp histology using optical diagnosis with high-definition white light, followed by narrow-band imaging without magnification and chromoendoscopy, as required. The primary outcome was accuracy of polyp characterisation using optical diagnosis compared with histopathology, the current gold standard. Accuracy of optical diagnosis to predict the next surveillance interval was also assessed and compared with surveillance intervals predicted by current guidelines using histopathology. This study is registered with ClinicalTrials.gov, NCT00888771. 363 polyps smaller than 10 mm were detected in 130 patients, of which 278 polyps had both optical and histopathological diagnosis. By histology, 198 of these polyps were adenomas and 80 were non-neoplastic lesions (of which 62 were hyperplastic). Optical diagnosis accurately diagnosed 186 of 198 adenomas (sensitivity 0.94; 95% CI 0.90-0.97) and 55 of 62 hyperplastic polyps (specificity 0.89; 0.78-0.95), with an overall accuracy of 241 of 260 (0.93, 0.89-0.96) for polyp characterisation. Using optical diagnosis alone, 82 of 130 patients could be given a surveillance interval immediately after colonoscopy, and the same interval was found after formal histopathology in 80 patients (98%) using British guidelines and in 78 patients (95%) using US multisociety guidelines. For polyps less than 10 mm in size, in-vivo optical diagnosis seems to be an acceptable strategy to assess polyp histopathology and future surveillance intervals. Dispensing with formal histopathology for most small polyps found at colonoscopy could improve the efficiency of the procedure and lead to substantial savings in time and cost. Leigh Family Trust, London, UK.

  12. Natural history of diminutive colorectal polyps: long-term prospective observation by colonoscopy.

    PubMed

    Mizuno, Ken-Ichi; Suzuki, Yutaka; Takeuchi, Manabu; Kobayashi, Masaaki; Aoyagi, Yutaka

    2014-04-01

    Endoscopic removal of colorectal adenomatous polyps effectively prevents cancer. However, the treatment strategy for diminutive polyps (diameter ≤ 5 mm) remains controversial. Understanding the natural history of diminutive polyps is a prerequisite to their effective management. We prospectively examined the natural history of diminutive polyps by long-term surveillance colonoscopy. A total of 207 polyps detected in 112 patients from December 1991 through March 2002 were studied. To avoid potential effects on size and morphological characteristics, all polyps were selected randomly and were followed without biopsy. Polyp size was estimated by comparing the lesion with the diameter of a biopsy forceps. Mean follow up was 7.8 years (SD, 4.8; range, 1.0-18.6; median, 7.5; interquartile range 3.4-11.2). Twenty-four polyps were resected endoscopically, and the histopathological diagnosis was mucosal high-grade neoplasia (Category 4) for one polyp, and mucosal low-grade neoplasia (Category 3) for 23 polyps. Mean linear size of the polyps was 3.2 mm (SD, 1.0; range, 1.3-5.0) at initial colonoscopy and 3.8 mm (SD 1.6; range 1.3-10.0) at final colonoscopy (P<0.01). Left-sided polyps showed a higher growth rate than right-sided polyps, and a type IIIL2 pit pattern was associated with a lower growth rate than a type IIIL1 pattern. We clarified the natural history of diminutive polyps by long-term follow-up colonoscopy. The benign course of diminutive polyps should be considered in the design of treatment strategies. © 2014 The Authors. Digestive Endoscopy © 2014 Japan Gastroenterological Endoscopy Society.

  13. Preoperative predictive factors for gallbladder cholesterol polyp diagnosed after laparoscopic cholecystectomy for polypoid lesions of gallbladder

    PubMed Central

    Lee, Hyojin; Park, Inseok; Cho, Hyunjin; Gwak, Geumhee; Yang, Keunho; Bae, Byung-Noe; Kim, Hong-Ju; Kim, Young Duk

    2016-01-01

    Backgrounds/Aims We investigated patients' clinical and radiological data to determine preoperative factors that predict cholesterol gallbladder (GB) polyps of large size, which can be helpful for decision on further diagnostic tools. Methods In this study, we retrospectively analyzed 126 patients who underwent laparoscopic cholecystectomy for GB polyps >10 mm diagnosed preoperatively by abdominal ultrasonography between February 2002 and February 2016 in Department of Surgery, Sanggye Paik Hospital. Patients were divided into non-cholesterol polyps group and cholesterol polyps group, based on the postoperative pathologic diagnosis. Clinical and radiological data, such as gender, age, body weight, height, body mass index (BMI), laboratory findings, size, number and shape of the polypoid lesions, and presence of the concurrent GB stone were compared between the two groups. Results Of the 126 cases, 73 had cholesterol polyps (57.9%) and 53 cases were non-cholesterol polyps (42.1%). The younger age (<48.5 years), size of polyp <13.25 mm and multiple polyps were independent predictive variables for cholesterol polyps, with odd ratios (OR) of 2.352 (p=0.045), 5.429 (p<0.001) and 0.472 (p<0.001), respectively. Conclusions Age, size and polyp number were used to predict cholesterol GB polyp among polypoid lesions of the gallbladder >10 mm. For cases in which these factors are not applicable, it is strongly recommended to evaluate further diagnostic tools, such as computed tomography, endoscopic ultrasonography and tumor markers. PMID:28261697

  14. Sonographic diagnosis of juvenile polyps in children.

    PubMed

    Zhang, Yao; Li, Shi-Xing; Xie, Li-Mei; Shi, Bo; Ju, Hao; Bai, Yu-Zuo; Zhang, Shu-Cheng

    2012-09-01

    The aim of this study was to assess the diagnostic value of ultrasonography for juvenile polyps in children and their sonographic characteristics. A retrospective analysis was performed of the ultrasound findings in 27 children who were diagnosed preoperatively with juvenile polyp within the intestinal tract by ultrasonography and then confirmed by colonoscopy, laparotomy and histopathology. The ultrasonic finding common to all polyps was an isolated intraluminal nodular or massive protrusion, associated with multiple mesh-like fluid areas of different sizes. In 25 children, surrounding pedicle-like low echoes of varying lengths were seen connecting with the polyps to form "mushroom" sign. The color Doppler showed abundant blood flow signals within all polyps and pedicles in a shape of a branch or an umbrella. For seven children with an intussusception, the polyp shadow was detected in the cervical part or interior of the intussusception. Ultrasonography is, thus, considered to be a feasible method for diagnosing intestinal juvenile polyp. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  15. Gallbladder polyps: factors affecting surgical decision.

    PubMed

    Sarkut, Pinar; Kilicturgay, Sadik; Ozer, Ali; Ozturk, Ersin; Yilmazlar, Tuncay

    2013-07-28

    To determine the factors affecting the decision to perform surgery, and the efficiency of ultrasonography (USG) in detecting gallbladder polyps (GP). Data for 138 patients who underwent cholecystectomy between 1996 and 2012 in our clinic with a diagnosis of GP were retrospectively analyzed. Demographic data, clinical presentation, principal symptoms, ultrasonographic and histopathological findings were evaluated. Patients were evaluated in individual groups according to the age of the patients (older or younger than 50 years old) and polyp size (bigger or smaller than 10 mm) and characteristics of the polyps (pseudopolyp or real polyps). χ(2) tests were used for the statistical evaluation of the data. The median age was 50 (26-85) years and 91 of patients were female. Of 138 patients who underwent cholecystectomy with GP diagnosis, only 99 had a histopathologically defined polyp; 77 of them had pseudopolyps and 22 had true polyps. Twenty-one patients had adenocarcinoma. Of these 21 patients, 11 were male, their median age was 61 (40-85) years and all malignant polyps had diameters > 10 mm (P < 0.0001). Of 138 patients in whom surgery were performed, 112 had ultrasonographic polyps with diameters < 10 mm. Of the other 26 patients who also had polyps with diameters > 10 mm, 22 had true polyps. The sensitivity of USG was 84.6% for polyps with diameters > 10 mm (P < 0.0001); however it was only 66% in polyps with diameters < 10 mm. The risk of malignancy was high in the patients over 50 years old who had single polyps with diameters > 10 mm.

  16. Expression of pituitary adenylate cyclase-activating polypeptide 1 and 2 receptor mRNA in gallbladder tissue of patients with gallstone or gallbladder polyps.

    PubMed

    Zhang, Zhen-Hai; Wu, Shuo-Dong; Gao, Hong; Shi, Gang; Jin, Jun-Zhe; Kong, Jing; Tian, Zhong; Su, Yang

    2006-03-07

    To detect the expression of pituitary adenylate cyclase-activating polypeptide receptor 1 (VPCAP1-R)and VPCAP2-R mRNA in gallbladder tissues of patients with gallstone or gallbladder polyps. The expression of VPCAP1-R and VPCAP2-R mRNA in gallbladder tissues was detected in 25 patients with gallstone,8 patients with gallbladder polyps and 7 donors of liver transplantation by reverse transcription polymerase chain reaction (RT-PCR). The VPCAP2-R mRNA expression level in the control group (1.09+/-0.58) was lower than that in the gallbladder polyp group (1.64+/-0.56) and the gallstone group (1.55+/-0.45) (P<0.05) while the VPCAP1-R mRNA expression level in the control group (1.15+/-0.23) was not apparently different from that in the gallbladder polyp group (1.28+/-0.56) and the gallstone group (1.27+/-0.38). The abnormal expression of VPCAP2-R mRNA in gallbladder tissue may play a role in the formation of gallbladder stone and gallbladder polyps.

  17. Serrated Colon Polyps as Precursors to Colorectal Cancer

    PubMed Central

    Sweetser, Seth; Smyrk, Thomas C.; Sinicrope, Frank A.

    2013-01-01

    Identification of the serrated neoplasia pathway has improved our understanding of the pathogenesis of colorectal cancer (CRC). Insights have included an increased recognition of the malignant potential of different types of serrated polyps, such as sessile and traditional serrated adenomas. Sessile serrated adenomas share molecular features with colon tumors, such as microsatellite instability and a methylator phenotype, indicating that these lesions are precursors that progress via the serrated neoplasia pathway. There is evidence that the serrated pathway contributes to interval or missed cancers. These data have important implications for clinical practice and CRC prevention, since hyperplastic polyps were previously regarded as having no malignant potential. Endoscopic detection of serrated polyps is a challenge because they are often inconspicuous with indistinct margins, and are frequently covered by adherent mucus. It is important for gastroenterologists to recognize the subtle endoscopic features of serrated polyps, which would facilitate their detection and removal, to ensure a high-quality colonoscopy examination. Recognition of the role of serrated polyps in colon carcinogenesis has led to the inclusion of these lesions in post-polypectomy surveillance guidelines. However, an enhanced effort is needed to identify and completely remove serrated adenomas, with the goal of increasing the effectiveness of colonoscopy to reduce CRC incidence. PMID:23267866

  18. Computer-aided detection systems to improve lung cancer early diagnosis: state-of-the-art and challenges

    NASA Astrophysics Data System (ADS)

    Traverso, A.; Lopez Torres, E.; Fantacci, M. E.; Cerello, P.

    2017-05-01

    Lung cancer is one of the most lethal types of cancer, because its early diagnosis is not good enough. In fact, the detection of pulmonary nodule, potential lung cancers, in Computed Tomography scans is a very challenging and time-consuming task for radiologists. To support radiologists, researchers have developed Computer-Aided Diagnosis (CAD) systems for the automated detection of pulmonary nodules in chest Computed Tomography scans. Despite the high level of technological developments and the proved benefits on the overall detection performance, the usage of Computer-Aided Diagnosis in clinical practice is far from being a common procedure. In this paper we investigate the causes underlying this discrepancy and present a solution to tackle it: the M5L WEB- and Cloud-based on-demand Computer-Aided Diagnosis. In addition, we prove how the combination of traditional imaging processing techniques with state-of-art advanced classification algorithms allows to build a system whose performance could be much larger than any Computer-Aided Diagnosis developed so far. This outcome opens the possibility to use the CAD as clinical decision support for radiologists.

  19. Omalizumab is effective in allergic and nonallergic patients with nasal polyps and asthma.

    PubMed

    Gevaert, Philippe; Calus, Lien; Van Zele, Thibaut; Blomme, Katrien; De Ruyck, Natalie; Bauters, Wouter; Hellings, Peter; Brusselle, Guy; De Bacquer, Dirk; van Cauwenberge, Paul; Bachert, Claus

    2013-01-01

    Adult patients with nasal polyps often have comorbid asthma, adding to the serious effect on the quality of life of these patients. Nasal polyps and asthma might represent a therapeutic challenge; inflammation in both diseases shares many features, such as airway eosinophilia, local IgE formation, and a T(H)2 cytokine profile. Omalizumab is a human anti-IgE mAb with proved efficacy in patients with severe allergic asthma. Omalizumab could be a treatment option for patients with nasal polyps and asthma. The goal of this study was to investigate the clinical efficacy of omalizumab in patients with nasal polyps and comorbid asthma. A randomized, double-blind, placebo-controlled study of allergic and nonallergic patients with nasal polyps and comorbid asthma (n = 24) was conducted. Subjects received 4 to 8 (subcutaneous) doses of omalizumab (n = 16) or placebo (n = 8). The primary end point was reduction in total nasal endoscopic polyp scores after 16 weeks. Secondary end points included a change in sinus computed tomographic scans, nasal and asthma symptoms, results of validated questionnaires (Short-Form Health Questionnaire, 31-item Rhinosinusitis Outcome Measuring Instrument, and Asthma Quality of Life Questionnaire), and serum/nasal secretion biomarker levels. There was a significant decrease in total nasal endoscopic polyp scores after 16 weeks in the omalizumab-treated group (-2.67, P = .001), which was confirmed by means of computed tomographic scanning (Lund-Mackay score). Omalizumab had a beneficial effect on airway symptoms (nasal congestion, anterior rhinorrhea, loss of sense of smell, wheezing, and dyspnea) and on quality-of-life scores, irrespective of the presence of allergy. Omalizumab demonstrated clinical efficacy in the treatment of nasal polyps with comorbid asthma, supporting the importance and functionality of local IgE formation in the airways. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  20. Evaluation of risk factors for the recurrence of colorectal polyps and colorectal cancer

    PubMed

    Ateş, Öztürk; Sivri, Bülent; Kılıçkap, Saadettin

    2017-11-13

    Background/aim: Colorectal adenomatous polyps are precursors of colorectal cancer (CRC), which can be prevented with surveillance colonoscopy. This study aimed to assess risk factors for the recurrence of colorectal polyps and CRC following polypectomy. Materials and methods: In this single-center trial, a total of 510 patients who applied to the endoscopy unit of Hacettepe University Hospital for various reasons and who were diagnosed with at least one colorectal adenomatous polyp between 2000 and 2010 were retrospectively analyzed. Patients with colorectal adenomatous polyps or CRC recurrences were examined in terms of clinical and histological risk factors. Results: A total of 190 (37.1%) patients had surveillance colonoscopy. Among them, 127 (66.3%) were found to have polyp recurrence. Of the parameters defined for polyp recurrence, no association was found between the number of polyps (1-2, ≥3) (1-3, ≥4) in the first colonoscopy and diabetes mellitus, hypertension, hyperlipidemia, sex, family history of colon malignancy, smoking, alcohol usage, size of polyp (<10 mm, ≥10 mm), or advanced histologic type of polyp. The only significant difference was observed in patients who had left-sided colon polyps. In the basal colonoscopy, 130 patients had been diagnosed with CRC, and a significant correlation was found between the number of polyps (1, ≥2) and polyp size (≥10 mm), anemia, high sedimentation rate (>25), and CRC. In the first surveillance colonoscopy, CRC was detected in 12 patients. There was a significant correlation between the development of CRC and advanced histological type, anemia with high erythrocyte sedimentation rate, polyp size (<10 mm, ≥10 mm), and the number of polyps (<3, ≥3). Conclusion: Patients with left-sided colon polyps had a high risk of developing colorectal polyp recurrence. Moreover, the risk of developing CRC increased in patients who had advanced histology, a polyp larger than 10 mm, or more than three polyps.

  1. Colon Capsule Endoscopy compared to Conventional Colonoscopy under routine screening conditions

    PubMed Central

    2010-01-01

    Background Colonoscopy (CSPY) for colorectal cancer screening has several limitations. Colon Capsule Endoscopy (PillCam Colon, CCE) was compared to CSPY under routine screening conditions. Methods We performed a prospective, single-center pilot study at a University Hospital. Data were obtained from November 2007 until May 2008. Patients underwent CCE on Day 1 and CSPY on Day 2. Outcomes were evaluated regarding sensitivity and specificity of polyp detection rate, with a significance level set at >5 mm. Results 59 individuals were included in this study, the results were evaluable in 56 patients (males 34, females 22; median age 59). CCE was complete in 36 subjects. Polyp detection rate for significant polyps was 11% on CSPY and 27% on CCE. 6/56 (11%) patients had polyps on CSPY not detected on CCE (miss rate). Overall sensitivity was 79% (95% confidence interval [CI], 61 to 90), specificity was 54% (95% CI, 35 to 70), positive predictive value (PPV) was 63% and negative predictive value (NPV) was 71%. Adjusted to significance of findings, sensitivity was 50% (95% CI, 19 to 81), specificity was 76% (95% CI, 63 to 86), PPV was 20% and NPV was 93%. Conclusion In comparison to the gold standard, the sensitivity of CCE for detection of relevant polyps is low, however, the high NPV supports its role as a possible screening tool. Trial Registration NCT00991003. PMID:20565828

  2. Gallbladder polyps: Factors affecting surgical decision

    PubMed Central

    Sarkut, Pinar; Kilicturgay, Sadik; Ozer, Ali; Ozturk, Ersin; Yilmazlar, Tuncay

    2013-01-01

    AIM: To determine the factors affecting the decision to perform surgery, and the efficiency of ultrasonography (USG) in detecting gallbladder polyps (GP). METHODS: Data for 138 patients who underwent cholecystectomy between 1996 and 2012 in our clinic with a diagnosis of GP were retrospectively analyzed. Demographic data, clinical presentation, principal symptoms, ultrasonographic and histopathological findings were evaluated. Patients were evaluated in individual groups according to the age of the patients (older or younger than 50 years old) and polyp size (bigger or smaller than 10 mm) and characteristics of the polyps (pseudopolyp or real polyps). χ2 tests were used for the statistical evaluation of the data. RESULTS: The median age was 50 (26-85) years and 91 of patients were female. Of 138 patients who underwent cholecystectomy with GP diagnosis, only 99 had a histopathologically defined polyp; 77 of them had pseudopolyps and 22 had true polyps. Twenty-one patients had adenocarcinoma. Of these 21 patients, 11 were male, their median age was 61 (40-85) years and all malignant polyps had diameters > 10 mm (P < 0.0001). Of 138 patients in whom surgery were performed, 112 had ultrasonographic polyps with diameters < 10 mm. Of the other 26 patients who also had polyps with diameters > 10 mm, 22 had true polyps. The sensitivity of USG was 84.6% for polyps with diameters > 10 mm (P < 0.0001); however it was only 66% in polyps with diameters < 10 mm. CONCLUSION: The risk of malignancy was high in the patients over 50 years old who had single polyps with diameters > 10 mm. PMID:23901228

  3. Correlation of Ki-67, p53, and Adnab-9 immunohistochemical staining and ploidy with clinical and histopathologic features of severely dysplastic colorectal adenomas.

    PubMed

    Sheikh, Rafiq A; Min, Byung Hee; Yasmeen, Shagufta; Teplitz, Raymond; Tesluk, Henry; Ruebner, Boris Henry; Tobi, Martin; Hatfield, James; Fligiel, Suzanne; Lawson, Michael J

    2003-01-01

    Variations of Ki-67, p53, and Adnab-9 monoclonal antibody reactions in colonic adenomas may be associated with colonic cancer risk. We studied the predictive value of these markers for adverse behavior in severely dysplastic colorectal adenomas, such as an associated carcinoma, multiplicity of adenomas, and subsequent development of adenomas. For this purpose we compared theclinical, gross, and histologic characteristics of highly dysplastic index polyps in 42 patients with Ki 67, p53, and Adnab-9 immunostaining and other molecular markers. Polyps were removed endoscopically, and severely dysplastic polyps were stained immunohistochemically with Ki-67, Adnab-9, and p53 protein by the avidin biotin conjugate (ABC) technique. Quantitative DNA (QDNA) was analyzed by computer-assisted image analysis. Ki-67 immunohistochemistry showed reversal of normal distribution of nuclear staining from the normal basal position to the upper third of the colonic crypts. This abnormality of immunostaining in dysplastic adenomas was the earliest detected by the panel we used. A statistically significant correlation was seen between invasiveness of carcinoma in the index polyp and polyp size (P = 0.003), sessile morphology (P = 0.037), and villous or tubulovillous histology (P = 0.019). In the index adenoma, p53 positivity was correlated with multiplicity at initial examination (P = 0.053), villous histology (P = 0.053), invasiveness of carcinoma (P < 0.003), and recurrence of colorectal adenomas (P = 0.025). Although p53 positivity and aneuploidy were correlated with invasiveness of carcinoma in the index polyp (P = 0.025), Adnab-9 positivity was not. However, Adnab-9 positivity in the index polyp was associated with multiplicity of adenomas (P = 0.04) as well as recurrence of adenomas (P < 0.024). In conclusion, in addition to the morphologic and histologic markers already known, Ki-67, Adnab-9 antibody, and p53 protein may be prognostic indicators useful in follow-up of patients with severely dysplastic colorectal adenomas. Adnab-9 antibody may identify a field defect in above-average-risk adenoma-bearing patients.

  4. Giant fibrovascular polyp of the oesophagus: a case report and review of the literature

    PubMed Central

    Chourmouzi, Danai; Drevelegas, Antonios

    2008-01-01

    Introduction We present a case of fibrovascular polyp, a rare submucosal tumour of the oesophagus that has been reported only sporadically in the literature. The biapproach for surgical removal of fibrovascular polyp has only been mentioned once in the literature. Case presentation A 65-year-old Greek man presented with a 9-month history of gradually progressive intermittent dysphagia. Radiologic work-up with oesophagogram and computed tomography revealed a large, sausage-shaped intraluminal polyp extending from the level of the cervical oesophagus to the level of the upper body of the stomach. The diagnosis of giant fibrovascular polyp was made radiographically and confirmed by endoscopic biopsy. The polyp was removed using a biapproach surgical technique: pharyngotomy and subsequent gastrostomy. Conclusion Fibrovascular polyp is a rare submucosal tumour. Proper treatment depends on accurate assessment of the origin, size, and vascularity of the pedicle and the size of the tumour. Choice of the appropriate surgical approach depends on the correct diagnosis, which can usually be indicated radiographically by the presence of a smooth, sausage-shaped defect with a discrete bulbous tip. PMID:18957112

  5. The role of high-resolution endoscopy and narrow-band imaging in the evaluation of upper GI neoplasia in familial adenomatous polyposis.

    PubMed

    Lopez-Ceron, Maria; van den Broek, Frank J C; Mathus-Vliegen, Elisabeth M; Boparai, Karam S; van Eeden, Susanne; Fockens, Paul; Dekker, Evelien

    2013-04-01

    The Spigelman classification stratifies cancer risk in familial adenomatous polyposis (FAP) patients with duodenal adenomatosis. High-resolution endoscopy (HRE) and narrow-band imaging (NBI) may identify lesions at high risk. To compare HRE and NBI for the detection of duodenal and gastric polyps and to characterize duodenal adenomas harboring advanced histology with HRE and NBI. Prospective, nonrandomized, comparative study. Retrospective image evaluation study. Tertiary-care center. Thirty-seven FAP patients undergoing surveillance upper endoscopies. HRE endoscopy was followed by NBI. The number of gastric polyps and Spigelman staging were compared. Duodenal polyp images were systematically reviewed in a learning and validation phase. Number of gastric and duodenal polyps detected by HRE and NBI and prevalence of specific endoscopic features in duodenal adenomas with advanced histology. NBI did not identify additional gastric polyps but detected more duodenal adenomas in 16 examinations, resulting in upgrades of the Spigelman stage in 2 cases (4.4%). Pictures of 168 duodenal adenomas (44% advanced histology) were assessed. In the learning phase, 3 endoscopic features were associated with advanced histology: white color, enlarged villi, and size ≥1 cm. Only size ≥1 cm was confirmed in the validation phase (odds ratio 3.0; 95% confidence interval, 1.2-7.4). Nonrandomized study, scant number of high-grade dysplasia adenomas. Inspection with NBI did not lead to a clinically relevant upgrade in the Spigelman classification and did not improve the detection of gastric polyps in comparison with HRE. The only endoscopic feature that predicted advanced histology of a duodenal adenoma was size ≥1 cm. Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  6. Ultrasonographically detected gallbladder polyps: A reason for concern? A seven-year follow-up study

    PubMed Central

    Kratzer, Wolfgang; Haenle, Mark M; Voegtle, Andrea; Mason, Richard A; Akinli, Atilla S; Hirschbuehl, Klaus; Schuler, Andreas; Kaechele, Volker

    2008-01-01

    Background The management of coincidental detected gallbladder polyps (GP) is still nebulous. There are few published data regarding their long-term growth. Objective of the present study was to investigate the prevalence and growth of gallbladder polyps in a survey of unselected subjects from the general population of a complete rural community. Methods A total of 2,415 subjects (1,261 women; 1,154 men) underwent ultrasound examination of the gallbladder, in November 1996 as part of a prospective study. Subjects in whom GP were detected at the initial survey underwent follow-up ultrasound examinations after 30 and 84 months. Results At the initial survey gallbladder polyps were detected in 34 subjects (1.4%; females: 1.1%, range 14 to 74 years; males: 1.7%, range 19 to 63 years). Median diameter was 5 ± 2.1 mm (range 2 to10 mm) at the initial survey, 5 mm ± 2.8 mm (range 2 to 12 mm) at 30 months and 4 ± 2.3 mm (range 2 to 9 mm) at 84 months. At the time of first follow-up no change in diameter was found in 81.0% (n = 17), reduction in diameter in 4.8% (n = 1) and increase in diameter in 14.3% (n = 3). At the time of second follow-up no increase in polyp diameter was found in 76.9% (n = 10) and reduction in diameter in 7.7% (n = 1). No evidence of malignant disease of the gallbladder was found. Conclusion Over a period of seven years little change was measured in the diameter of gallbladder polyps. There was no evidence of malignant disease of the gallbladder in any subject. PMID:18793401

  7. Ultrasonographically detected gallbladder polyps: a reason for concern? A seven-year follow-up study.

    PubMed

    Kratzer, Wolfgang; Haenle, Mark M; Voegtle, Andrea; Mason, Richard A; Akinli, Atilla S; Hirschbuehl, Klaus; Schuler, Andreas; Kaechele, Volker

    2008-09-15

    The management of coincidental detected gallbladder polyps (GP) is still nebulous. There are few published data regarding their long-term growth. Objective of the present study was to investigate the prevalence and growth of gallbladder polyps in a survey of unselected subjects from the general population of a complete rural community. A total of 2,415 subjects (1,261 women; 1,154 men) underwent ultrasound examination of the gallbladder, in November 1996 as part of a prospective study. Subjects in whom GP were detected at the initial survey underwent follow-up ultrasound examinations after 30 and 84 months. At the initial survey gallbladder polyps were detected in 34 subjects (1.4%; females: 1.1%, range 14 to 74 years; males: 1.7%, range 19 to 63 years). Median diameter was 5 +/- 2.1 mm (range 2 to 10 mm) at the initial survey, 5 mm +/- 2.8 mm (range 2 to 12 mm) at 30 months and 4 +/- 2.3 mm (range 2 to 9 mm) at 84 months. At the time of first follow-up no change in diameter was found in 81.0% (n = 17), reduction in diameter in 4.8% (n = 1) and increase in diameter in 14.3% (n = 3). At the time of second follow-up no increase in polyp diameter was found in 76.9% (n = 10) and reduction in diameter in 7.7% (n = 1). No evidence of malignant disease of the gallbladder was found. Over a period of seven years little change was measured in the diameter of gallbladder polyps. There was no evidence of malignant disease of the gallbladder in any subject.

  8. Active BRAF-V600E is the key player in generation of a sessile serrated polyp-specific DNA methylation profile

    PubMed Central

    Dehghanizadeh, Somaye; Khoddami, Vahid; Mosbruger, Timothy L.; Hammoud, Sue S.; Edes, Kornelia; Berry, Therese S.; Done, Michelle; Samowitz, Wade S.; DiSario, James A.; Luba, Daniel G.; Burt, Randall W.

    2018-01-01

    Background Sessile serrated polyps (SSPs) have emerged as important precursors for a large number of sporadic colorectal cancers. They are difficult to detect during colonoscopy due to their flat shape and the excessive amounts of secreted mucin that cover the polyps. The underlying genetic and epigenetic basis for the emergence of SSPs is largely unknown with existing genetic studies confined to a limited number of oncogenes and tumor suppressors. A full characterization of the genetic and epigenetic landscape of SSPs would provide insight into their origin and potentially offer new biomarkers useful for detection of SSPs in stool samples. Methods We used a combination of genome-wide mutation detection, exome sequencing and DNA methylation profiling (via methyl-array and whole-genome bisulfite sequencing) to analyze multiple samples of sessile serrated polyps and compared these to familial adenomatous polyps. Results Our analysis revealed BRAF-V600E as the sole recurring somatic mutation in SSPs with no additional major genetic mutations detected. The occurrence of BRAF-V600E was coincident with a unique DNA methylation pattern revealing a set of DNA methylation markers showing significant (~3 to 30 fold) increase in their methylation levels, exclusively in SSP samples. These methylation patterns effectively distinguished sessile serrated polys from adenomatous polyps and did so more effectively than parallel gene expression profiles. Conclusions This study provides an important example of a single oncogenic mutation leading to reproducible global DNA methylation changes. These methylated markers are specific to SSPs and could be of important clinical relevance for the early diagnosis of SSPs using non-invasive approaches such as fecal DNA testing. PMID:29590112

  9. Gastric polyps diagnosed by double-contrast upper gastrointestinal barium X-ray radiography mostly arise from the Helicobacter pylori-negative stomach with low risk of gastric cancer in Japan.

    PubMed

    Takeuchi, Chihiro; Yamamichi, Nobutake; Shimamoto, Takeshi; Takahashi, Yu; Mitsushima, Toru; Koike, Kazuhiko

    2017-03-01

    Double-contrast upper gastrointestinal barium X-ray radiography (UGI-XR) is a method broadly used for gastric cancer screening in Japan. Gastric polyp is one of the most frequent findings detected by UGI-XR, but how to handle it remains controversial. Gastric polyps of the 17,264 generally healthy subjects in Japan who underwent UGI-XR or upper gastrointestinal endoscopy (UGI-ES) in 2010 were analyzed. Of the 6,433 UGI-XR examinees (3,405 men and 3,028 women, 47.4 ± 9.0 years old), gastric polyps were detected in 464 men (13.6 %) and 733 women (24.2 %) and were predominantly developed on the non-atrophic gastric mucosa (p < 0.0001). Multiple logistic regression analysis showed that the presence of gastric polyps has significant association with lower value of serum anti-Helicobacter pylori IgG titer, female gender, lighter smoking habit, older age, and normal range of body mass index (≥18.5 and <25), but not with drinking or serum pepsinogen I/II ratio. During the 3-year follow-up, gastric cancer occurred in 7 subjects (0.11 %), but none of them had gastric polyps at the beginning of the follow-up period. Of the 2,722 subjects with gastric polyps among the 10,831 UGI-ES examinees in the same period, 2,446 (89.9 %) had fundic, 267 (9.8 %) had hyperplastic, and 9 (0.3 %) had adenomatous/cancerous polyps. Gastric polyps diagnosed by UGI-XR predominantly arise on the Helicobacter pylori-negative gastric mucosa with a low risk of gastric cancer in Japan. In the prospective observation, none of the UGI-XR examinees with gastric polyps developed gastric cancer for at least 3 years subsequently.

  10. A Metric for Reducing False Positives in the Computer-Aided Detection of Breast Cancer from Dynamic Contrast-Enhanced Magnetic Resonance Imaging Based Screening Examinations of High-Risk Women.

    PubMed

    Levman, Jacob E D; Gallego-Ortiz, Cristina; Warner, Ellen; Causer, Petrina; Martel, Anne L

    2016-02-01

    Magnetic resonance imaging (MRI)-enabled cancer screening has been shown to be a highly sensitive method for the early detection of breast cancer. Computer-aided detection systems have the potential to improve the screening process by standardizing radiologists to a high level of diagnostic accuracy. This retrospective study was approved by the institutional review board of Sunnybrook Health Sciences Centre. This study compares the performance of a proposed method for computer-aided detection (based on the second-order spatial derivative of the relative signal intensity) with the signal enhancement ratio (SER) on MRI-based breast screening examinations. Comparison is performed using receiver operating characteristic (ROC) curve analysis as well as free-response receiver operating characteristic (FROC) curve analysis. A modified computer-aided detection system combining the proposed approach with the SER method is also presented. The proposed method provides improvements in the rates of false positive markings over the SER method in the detection of breast cancer (as assessed by FROC analysis). The modified computer-aided detection system that incorporates both the proposed method and the SER method yields ROC results equal to that produced by SER while simultaneously providing improvements over the SER method in terms of false positives per noncancerous exam. The proposed method for identifying malignancies outperforms the SER method in terms of false positives on a challenging dataset containing many small lesions and may play a useful role in breast cancer screening by MRI as part of a computer-aided detection system.

  11. High-resolution melting (HRM) re-analysis of a polyposis patients cohort reveals previously undetected heterozygous and mosaic APC gene mutations.

    PubMed

    Out, Astrid A; van Minderhout, Ivonne J H M; van der Stoep, Nienke; van Bommel, Lysette S R; Kluijt, Irma; Aalfs, Cora; Voorendt, Marsha; Vossen, Rolf H A M; Nielsen, Maartje; Vasen, Hans F A; Morreau, Hans; Devilee, Peter; Tops, Carli M J; Hes, Frederik J

    2015-06-01

    Familial adenomatous polyposis is most frequently caused by pathogenic variants in either the APC gene or the MUTYH gene. The detection rate of pathogenic variants depends on the severity of the phenotype and sensitivity of the screening method, including sensitivity for mosaic variants. For 171 patients with multiple colorectal polyps without previously detectable pathogenic variant, APC was reanalyzed in leukocyte DNA by one uniform technique: high-resolution melting (HRM) analysis. Serial dilution of heterozygous DNA resulted in a lowest detectable allelic fraction of 6% for the majority of variants. HRM analysis and subsequent sequencing detected pathogenic fully heterozygous APC variants in 10 (6%) of the patients and pathogenic mosaic variants in 2 (1%). All these variants were previously missed by various conventional scanning methods. In parallel, HRM APC scanning was applied to DNA isolated from polyp tissue of two additional patients with apparently sporadic polyposis and without detectable pathogenic APC variant in leukocyte DNA. In both patients a pathogenic mosaic APC variant was present in multiple polyps. The detection of pathogenic APC variants in 7% of the patients, including mosaics, illustrates the usefulness of a complete APC gene reanalysis of previously tested patients, by a supplementary scanning method. HRM is a sensitive and fast pre-screening method for reliable detection of heterozygous and mosaic variants, which can be applied to leukocyte and polyp derived DNA.

  12. The efficacy and safety of argon plasma coagulation (APC) in the management of polyp remnants in stomach and colon.

    PubMed

    Neneman, B; Gasiorowska, A; Małecka-Panas, E

    2006-01-01

    Endoscopic treatment of sessile and semipedunculated polyps remains controversial. Residual tissue remains frequently after endoscopic snare polypectomy. The aim of the study was to assess the outcome and safety of argon plasma coagulation (APC) in the management of gastric and colorectal polyp remnants after polypectomy, and to search for clinical parameters useful in predicting the efficacy of this technique. This prospective study comprised 18 patients with gastric polyps and 29 with colonic polyps found in upper and lower GI endoscopy. Overall 22 gastric polyps and 58 colonic polyps have been detected. All those polyps were removed at colonoscopy with the diathermic snare and the polyp remnants were destroyed with APC using Argon Beamer source (Erbe, Germany). Follow-up endoscopies have been performed 1, 3 and 6 months after the treatment completion. Pathologic examination revealed 10 hyperplastic polyps and 12 tubular adenomas of the stomach. Effective destruction of polyp remnants was achieved in 20 (90.9%) gastric polyps in 16 (88.9%) patients. Significant positive correlation was demonstrated between the power output, APC sessions number and polyp location in the prepyloric part, its size and adenomatous content. Among colonic polyps there were: 17 hyperplastic, 26 tubular, 8 tubulo-villous, 4 villous adenomas and 3 inflammatory pseudopolyps. Effective destruction of remnant polyp tissue was obtained in 56 (96.4%) polyps in 27 (93.1%) patients. A significant positive correlation between the power output and the size, distal location and villous texture of the polyp has been demonstrated. No complications other than mild abdominal distention have been encountered. APC is an effective and safe method in the management of polyp remnants in the stomach and colon. The application of higher electric power and numerous APC sessions are necessary to remove residues of large gastric polyps located in the prepyloric part and of with adenomatous content. In the case of colonic polyps the application of higher electric power should be recommended in case of large-sized lesions, located in rectum and of villous texture.

  13. Carcinoma in gastric hyperplastic polyps: A phenotypic study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zea-Iriarte, W.L.; Sekine, Ichiro; Itsuno, Minoru

    1996-02-01

    One-hundred twelve hyperplastic polyps were analyzed. The aim was to study their malignant transformation. Among them, four hyperplastic polyps harbored adenocarcinoma; two were from our own institution (1.8%). The majority were pedunculated and located in the antrum with an average of 14.5 mm in diameter. The four polyps bore well-differentiated adenocarcinoma. Dysplasia and intestinal metaplasia were detected in two and three polyps, respectively. The cancer and dysplastic foci shared the same type of neutral and acid mucosubstances. p53 oncoprotein was positive in three cancer foci and in the dysplastic areas, and nucleolar organizer region counts were higher in the cancermore » foci. In conclusion, hyperplastic polyps have malignant potential. Such possibility increases in polyps larger than 14.5 mm. In our cases, the carcinoma foci may have arisen from dysplastic areas. Once the neoplastic changes occur, the cancer cells proliferate and behave as other adenocarcinomas of the stomach. 40 refs., 7 figs., 5 tabs.« less

  14. Evaluation of promoter methylation status of MLH1 gene in Iranian patients with colorectal tumors and adenoma polyps.

    PubMed

    Zarandi, Ashkan; Irani, Shiva; Savabkar, Sanaz; Chaleshi, Vahid; Ghavideldarestani, Maryam; Mirfakhraie, Reza; Khodadoostan, Mahsa; Nazemalhosseini-Mojarad, Ehsan; Asadzadeh Aghdaei, Hamid

    2017-01-01

    The aim of this study was to evaluate the methylation status of the promoter region of MLH1 gene in colorectal cancer (CRC) and its precursor lesions as well as elucidate its association with various clinicopathological characteristics among Iranian population. Epigenetic silencing of mismatch repair genes, such as MLH1 , by methylation of CpG islands of their promoter region has been proved to be an important mechanism in colorectal carcinogenesis. Fifty colorectal cancer and polyp tissue samples including 13 Primary colorectal tumor and 37 Adenoma polyp samples were enrolled in this study. Methylation-specific polymerase chain reaction (MSP) was performed to find the frequency of MLH1 Promoter Methylation. Promoter methylation of MLH1 gene was detected in 5 out of 13 tumor tissues and 4 out of 37 adenoma polyp. The frequency of MLH1 methylation in tumor samples was significantly higher compared to that in polyp tissues (P= 0.026). No significant association was observed between MLH1 promoter methylation and clinicopathological characteristics of the patients. The frequency of  MLH1  promoter methylation in CRC and colon polyp was 18%. Our findings indicated that methylation of MLH1 promoter region alone cannot be considered as a biomarker for early detection of CRC.

  15. Expression of pituitary adenylate cyclase-activating polypeptide 1 and 2 receptor mRNA in gallbladder tissue of patients with gallstone or gallbladder polyps

    PubMed Central

    Zhang, Zhen-Hai; Wu, Shuo-Dong; Gao, Hong; Shi, Gang; Jin, Jun-Zhe; Kong, Jing; Tian, Zhong; Su, Yang

    2006-01-01

    AIM: To detect the expression of pituitary adenylate cyclase-activating polypeptide receptor 1 (VPCAP1-R) and VPCAP2-R mRNA in gallbladder tissues of patients with gallstone or gallbladder polyps. METHODS: The expression of VPCAP1-R and VPCAP2-R mRNA in gallbladder tissues was detected in 25 patients with gallstone, 8 patients with gallbladder polyps and 7 donors of liver transplantation by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: The VPCAP2-R mRNA expression level in the control group (1.09±0.58) was lower than that in the gallbladder polyp group (1.64 ± 0.56) and the gallstone group (1.55±0.45) (P < 0.05) while the VPCAP1-R mRNA expression level in the control group (1.15 ± 0.23) was not apparently different from that in the gallbladder polyp group (1.28±0.56) and the gallstone group (1.27 ± 0.38). CONCLUSION: The abnormal expression of VPCAP2-R mRNA in gallbladder tissue may play a role in the formation of gallbladder stone and gallbladder polyps. PMID:16552823

  16. Ultrasound follow-up for gallbladder polyps less than 6 mm may not be necessary.

    PubMed

    Pedersen, Malene Roland V; Dam, Claus; Rafaelsen, Søren Rafael

    2012-10-01

    The management of ultrasound (US) detected gallbladder (GB) polyps remains a dilemma. The aim of this study was to assess the size distribution and the outcome of US follow-up of GB polyps. The study was approved by the Danish Data Protection Agency. US reports from patients examined with abdominal US in our department from January 2008 to the end of December 2009 were reviewed with a view to including all patients with GB polyps. Patients with GB polyps are routinely recommended a 2-year follow-up with US every six months. The GB polyp size was recorded at baseline and at subsequent US reports. Pathology reports were finally reviewed for all patients with GB polyps to check who underwent cholecystectomy and to register the histological diagnosis. A total of 203 patients (median age 54 years; range 19-95 years) with GB polyps were included; 89 (44%) men and 114 (56%) women. The mean polyp size was 5 mm (range 2-40 mm). In 143 patients (70%) the GB polyp diameter was less than 6 mm. The first US follow-up was performed in 120 patients (59%), and only 31 (15%) completed the full 2-year US follow-up programme. Polyp size was stable in 100 patients, decreased in five patients, increased in eight and resolved in 15 patients. A total of 13 patients (6%) underwent cholecystectomy. Of the 203 patients, none showed neoplastic or malignant GB polyps. We recommend that follow-up US of patients with GB polyps < 6 mm is avoided. Alternatively, the intervals between US follow-up of GB polyps < 6 mm may be extended. not relevant. not relevant.

  17. Giant Hypopharyngeal Fibrovascular Polyp: A Case Report and Review of the Relevant Literature.

    PubMed

    Haytoglu, Suheyl; Tuhanioglu, Birgul; Bozkurttan, Abdurrahman; Arikan, Osman Kursat

    2015-01-01

    Fibrovascular polyps occur most commonly in the cervical esophagus and are extremely rare in the hypopharynx. In this paper, we report a case of fibrovascular polyp of a 52-year-old female, who presented with progressive dysphagia and weight loss and regurgitating a mass from her mouth. By the endoscopic examination, a polyp covered by normal mucosa with a wide stalk was detected at the hypopharynx. The pedicle of the mass was identified under general anesthesia and the 13 × 3 × 2 cm mass was completely resected perorally. Histopathological examination of the tumor showed oedematous subepithelial fibrous stroma, surrounded by squamous epithelium and containing many congested vascular structures. No recurrence was detected over one year of follow-up. This case highlights the need for clinicians to be aware of this rare entity and to develop the best approach to patient management.

  18. Blood test using surface-enhanced Raman spectroscopy with colloidal silver nanoparticle substrate to detect polyps and colorectal cancer (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Wang, Wenbo; Feng, Shangyuan; Tai, Isabella T.; Chen, Guannan; Chen, Rong; Zeng, Haishan

    2016-03-01

    Colorectal cancer (CRC) is the third most common type of cancer and forth leading cause of cancer-related death. Early diagnosis is the key to long-term patient survival. Programmatic screening for the general population has shown to be cost-effective in reducing the incidence and mortality from CRC. Current CRC screening strategy relies on a broad range of test techniques such as fecal based tests and endoscopic exams. Occult blood tests like fecal immunochemical test is a cost effective way to detect CRC but have limited diagnostic values in detecting adenomatous polyp, the most treatable precursor to CRC. In the present work, we proposed the use of surface enhanced Raman spectroscopy (SERS) with silver nanoparticles as substrate to analyze blood plasma for detecting both CRC and adenomatous polyps. Blood plasma samples collected from healthy subjects and patients diagnosed with adenomas and CRC were prepared with nanoparticles and measured using a real-time fiber optic probe based Raman system. The collected SERS spectra are analyzed with partial least squares-discriminant analysis. Classification of normal versus CRC plus adenomatous polyps achieved diagnostic sensitivity of 86.4% and specificity of 80%. This exploratory study suggests that blood plasma SERS analysis has potential to become a screening test for detecting both CRC and adenomas.

  19. Korean Guidelines for Colorectal Cancer Screening and Polyp Detection

    PubMed Central

    Lee, Bo-In; Hong, Sung Pil; Kim, Seong-Eun; Kim, Se Hyung; Hong, Sung Noh; Yang, Dong-Hoon; Shin, Sung Jae; Lee, Suck-Ho; Park, Dong Il; Kim, Young-Ho; Kim, Hyun Jung; Yang, Suk-Kyun; Kim, Hyo Jong; Jeon, Hae Jeong

    2012-01-01

    Now colorectal cancer is the second most common cancer in males and the fourth most common cancer in females in Korea. Since most of colorectal cancers occur after the prolonged transformation of adenomas into carcinomas, early detection and removal of colorectal adenomas are one of the most effective methods to prevent colorectal cancer. Considering the increasing incidence of colorectal cancer and polyps in Korea, it is very important to establish Korean guideline for colorectal cancer screening and polyp detection. The guideline was developed by the Korean Multi-Society Take Force and we tried to establish the guideline by evidence-based methods. Parts of the statements were draw by systematic reviews and meta-analyses. Herein we discussed epidemiology of colorectal cancers and adenomas in Korea and optimal methods for screening of colorectal cancer and detection of adenomas including fecal occult blood tests, radiologic tests, and endoscopic examinations. PMID:22741131

  20. MicroRNA signatures of colonic polyps on screening and histology

    PubMed Central

    Tsikitis, Vassiliki L.; Potter, Amiee; Mori, Motomi; Buckmeier, Julie A.; Preece, Christina R.; Harrington, Christina A.; Bartley, Angela N.; Bhattacharyya, Achyut K.; Hamilton, Stanley R.; Lance, M. Peter; Thompson, Patricia A.

    2016-01-01

    Colorectal cancer (CRC) and adenoma adjacent to cancer exhibit distinct microRNA (miR) alterations in an apparent mucosa-to-adenocarcinoma sequence. The pattern of microRNAs in screen-detected polyps in relation to histologic features and cancer risk has not been investigated. miR expression analysis was performed on normal mucosa (NM), hyperplastic polyps (HPs), tubular adenomas (TAs), tubulovillous adenomas or high-grade dysplasia (TVHGs), and serrated polyps (sessile serrated adenoma/polyps, SSA/Ps, and traditional serrated adenomas, TSAs) in biopsy specimens from 109 patients undergoing screening/surveillance colonoscopy. Generalized linear models were used to identify differentially expressed miRs by histologic type and logistic regression to identify miR predictors of histopathology. False discovery rate (FDR) was used to control for multiple comparisons. We identified 99 miRs differing in at least one of five histopathologic groups (FDR ≤ 0.05). In a comparison of HPNM vs. TVHG, the top most up- and down-regulated miRs in HPNM included miR-145, -143, -107, -194, and -26a (upregulated), and miR-663, -1268, -320b, -1275, and -320b (down-regulated) (FDR P-value < 0.05). miR-145 and -619 showed high accuracy to discriminate low- from high-risk polyps without serrated histology (TVHG vs. HPNM+TA) (CI= 95.6%), whereas miRs-124, -143, and -30a showed high accuracy of separating high-risk polyps (TVHG+TSA) from low-risk polyps (HPNM+TA+SSA/P) (CI=96.0%). For TSAs, miRs-125b and -199a were uniquely downregulated relative to HPNMs, and miR-335, -222 and -214 discriminated between non-serrated and serrated histology. Our data support the presence of CRC-associated miR alterations in screen-detected adenomas that may be useful for risk stratification for surveillance interval planning. PMID:27658891

  1. Computer vision and augmented reality in gastrointestinal endoscopy

    PubMed Central

    Mahmud, Nadim; Cohen, Jonah; Tsourides, Kleovoulos; Berzin, Tyler M.

    2015-01-01

    Augmented reality (AR) is an environment-enhancing technology, widely applied in the computer sciences, which has only recently begun to permeate the medical field. Gastrointestinal endoscopy—which relies on the integration of high-definition video data with pathologic correlates—requires endoscopists to assimilate and process a tremendous amount of data in real time. We believe that AR is well positioned to provide computer-guided assistance with a wide variety of endoscopic applications, beginning with polyp detection. In this article, we review the principles of AR, describe its potential integration into an endoscopy set-up, and envisage a series of novel uses. With close collaboration between physicians and computer scientists, AR promises to contribute significant improvements to the field of endoscopy. PMID:26133175

  2. Randomized, controlled trial of standard-definition white-light, high-definition white-light, and narrow-band imaging colonoscopy for the detection of colon polyps and prediction of polyp histology.

    PubMed

    Rastogi, Amit; Early, Dayna S; Gupta, Neil; Bansal, Ajay; Singh, Vikas; Ansstas, Michael; Jonnalagadda, Sreenivasa S; Hovis, Christine E; Gaddam, Srinivas; Wani, Sachin B; Edmundowicz, Steven A; Sharma, Prateek

    2011-09-01

    Missing adenomas and the inability to accurately differentiate between polyp histology remain the main limitations of standard-definition white-light (SD-WL) colonoscopy. To compare the adenoma detection rates of SD-WL with those of high-definition white-light (HD-WL) and narrow-band imaging (NBI) as well as the accuracy of predicting polyp histology. Multicenter, prospective, randomized, controlled trial. Two academic medical centers in the United States. Subjects undergoing screening or surveillance colonoscopy. Subjects were randomized to undergo colonoscopy with one of the following: SD-WL, HD-WL, or NBI. The proportion of subjects detected with adenomas, adenomas detected per subject, and the accuracy of predicting polyp histology real time. A total of 630 subjects were included. The proportion of subjects with adenomas was 38.6% with SD-WL compared with 45.7% with HD-WL and 46.2% with NBI (P = .17 and P = .14, respectively). Adenomas detected per subject were 0.69 with SD-WL compared with 1.12 with HD-WL and 1.13 with NBI (P = .016 and P = .014, respectively). HD-WL and NBI detected more subjects with flat and right-sided adenomas compared with SD-WL (all P values <.005). NBI had a superior sensitivity (90%) and accuracy (82%) to predict adenomas compared with SD-WL and HD-WL (all P values <.005). Academic medical centers with experienced endoscopists. There was no difference in the proportion of subjects with adenomas detected with SD-WL, HD-WL, and NBI. However, HD-WL and NBI detected significantly more adenomas per subject (>60%) compared with SD-WL. NBI had the highest accuracy in predicting adenomas in real time during colonoscopy. ( NCT 00614770.). Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  3. Outcome Analyses of 15,189 Screenings Via Colonoscopy.

    PubMed

    Liu, Lan; Gao, Hongwei; Yu, Weihua; Zhang, Shanyan; Guo, Jianqiang; Zhu, Kongxi

    2017-10-01

    This study investigated the detection rates of common colorectal diseases during colonoscopy procedures to provide reference for clinical diagnoses in China. A total of 15,189 participants, who underwent total colonoscopy, were studied. We analyzed the detection rates of common colorectal diseases in different sex, age, and decade groups. The most common indication for colonoscopy is abdominal pain followed by change in bowel habits. Among the 15,189 participants, 5658 cases (37.25%) were normal. The most common positive finding was colorectal polyp (27.32%) followed by nonspecific colitis (12.06%), colorectal cancer (CRC) (7.71%), and ulcerative colitis (4.64%). The frequencies of polyp (31.56% vs. 21.99%; P=0.000) and CRC (8.28% vs. 7.00%; P=0.004) were higher in males than in females. By contrast, ischemic colitis (0.08% vs. 0.31%; P=0.001) and melanosis coli (1.15% vs. 1.87%; P=0.000) were more seen in females than in males. In addition, the detection rates for CRC (2.42% vs. 7.18% vs. 16.67%; P=0.000), colorectal polyp (17.65% vs. 32.27% vs. 34.73%; P=0.000), ischemic colitis (0.09% vs. 0.19% vs. 0.32%; P=0.033), and melanosis coli (0.71% vs. 1.09% vs. 3.21%; P=0.000) increased with age. The frequent positive findings were colorectal polyp, nonspecific colitis, and CRC. Patients showing alarming symptoms definitely require colonoscopy. The detection rates for colorectal polyp and melanosis coli were significantly higher in the later decade, so we should focus on these deseases.

  4. The role of human papilloma virus and herpes viruses in the etiology of nasal polyposis.

    PubMed

    Koçoğlu, Mücahide Esra; Mengeloğlu, Fırat Zafer; Apuhan, Tayfun; Özsoy, Şeyda; Yilmaz, Beyhan

    2016-02-17

    The aim of this study was to investigate the etiological role of human papilloma virus (HPV), herpes simplex virus (HSV), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human herpes virus-6 (HHV-6) and -7 (HHV-7) in the occurrence of nasal polyposis. Nasal polyp samples from 30 patients with nasal polyposis and normal nasal mucosa from 10 patients without nasal polyps were obtained. DNA was extracted from tissues. Real-time polymerase chain reaction was performed for all runs. No HSV-1, HSV-2, or VZV was detected in the samples. Among the patient samples, EBV and HHV-7 DNA were detected in 18 (60%), HHV-6 was detected in 20 (66.7%), and HPV was detected in 4 (13.3%) samples. Among the controls, CMV DNA was positive in one (10%). EBV was positive in 5 (50%), HHV-6 and HHV-7 were positive in 7 (70%), and HPV was positive in 2 (20%) samples. No significant difference was found among the groups with any test in terms of positivity. The association of Herpesviridae and HPV with the pathogenesis of nasal polyps was investigated in this study and no relationship was found. Thus, these viruses do not play a significant role in the formation of nasal polyps.

  5. Prevalence of and risk factors for gallbladder polyps detected by ultrasonography among healthy Chinese: analysis of 34 669 cases.

    PubMed

    Lin, Wey-Ran; Lin, Deng-Yn; Tai, Dar-In; Hsieh, Sen-Yung; Lin, Chun-Yen; Sheen, I-Shyan; Chiu, Cheng-Tang

    2008-06-01

    Gallbladder (GB) polyps are tumor or tumor-like projections arising from GB mucosa. Although most polyps are benign, some early GB carcinomas present as polypoid lesions. The diagnosis of GB polyps is relatively easy by ultrasonography. Although numerous studies have investigated GB polyps, few studies have addressed the prevalence of and factors associated with GB polyps for specific ethnic populations. This study analyzes the prevalence and factors associated with GB polyps in a Chinese population who can afford a paid general checkup. The prevalence of and risk factors for GB polyps diagnosed by ultrasonography were retrospectively investigated in 34 669 Chinese patients who underwent a general checkup at Chang Gung Memorial Hospital (Taipei, Taiwan) between 2000 and 2003. Demographic, hemogram, serum biochemistry, hepatitis B surface antigen, hepatitis C antibody, and ultrasonography study data was available for all the patients. The correlations between the prevalence of GB polyps and age, sex, body height, body weight, body mass index, hemogram, serum biochemistry, and viral markers were examined for all the patients. Excluding the patients who underwent cholecystectomy, the overall prevalence of GB polyps was 9.5% and highest for middle-aged males. The analyzed risk factors with increased odds ratios (OR) for the development of GB polyps were male sex (OR 0.646, P < 0.0005) and hepatitis B virus surface antigen positivity (OR 1.113, P < 0.0005). Other demographic characteristics and biochemical parameters, including body height, body weight, body mass index, lipid profile, chronic hepatitis C virus infection, and liver function did not correlate with the presence of GB polyps. The prevalence of GB polyps among the Chinese in this study is higher than that reported for other populations. Chinese males and other patients with chronic hepatitis B viral infections have a high risk for developing GB polyps.

  6. Deep learning-based depth estimation from a synthetic endoscopy image training set

    NASA Astrophysics Data System (ADS)

    Mahmood, Faisal; Durr, Nicholas J.

    2018-03-01

    Colorectal cancer is the fourth leading cause of cancer deaths worldwide. The detection and removal of premalignant lesions through an endoscopic colonoscopy is the most effective way to reduce colorectal cancer mortality. Unfortunately, conventional colonoscopy has an almost 25% polyp miss rate, in part due to the lack of depth information and contrast of the surface of the colon. Estimating depth using conventional hardware and software methods is challenging in endoscopy due to limited endoscope size and deformable mucosa. In this work, we use a joint deep learning and graphical model-based framework for depth estimation from endoscopy images. Since depth is an inherently continuous property of an object, it can easily be posed as a continuous graphical learning problem. Unlike previous approaches, this method does not require hand-crafted features. Large amounts of augmented data are required to train such a framework. Since there is limited availability of colonoscopy images with ground-truth depth maps and colon texture is highly patient-specific, we generated training images using a synthetic, texture-free colon phantom to train our models. Initial results show that our system can estimate depths for phantom test data with a relative error of 0.164. The resulting depth maps could prove valuable for 3D reconstruction and automated Computer Aided Detection (CAD) to assist in identifying lesions.

  7. Prospective randomized controlled trial evaluating cap-assisted colonoscopy vs standard colonoscopy

    PubMed Central

    Tee, Hoi-Poh; Corte, Crispin; Al-Ghamdi, Hamdan; Prakoso, Emilia; Darke, John; Chettiar, Raman; Rahman, Wassim; Davison, Scott; Griffin, Sean P; Selby, Warwick S; Kaffes, Arthur J

    2010-01-01

    AIM: To study the significance of cap-fitted colonoscopy in improving cecal intubation time and polyp detection rate. METHODS: This study was a prospective randomized controlled trial conducted from March 2008 to February 2009 in a tertiary referral hospital at Sydney. The primary end point was cecal intubation time and the secondary endpoint was polyp detection rate. Consecutive cases of total colonoscopy over a 1-year period were recruited. Randomization into either standard colonoscopy (SC) or cap-assisted colonoscopy (CAC) was performed after consent was obtained. For cases randomized to CAC, one of the three sizes of cap was used: D-201-15004 (with a diameter of 15.3 mm), D-201-14304 (14.6 mm) and D-201-12704 (13.0 mm). All of these caps were produced by Olympus Medical Systems, Japan. Independent predictors for faster cecal time and better polyp detection rate were also determined from this study. RESULTS: There were 200 cases in each group. There was no significant difference in terms of demographic characteristics between the two groups. CAC, when compared to the SC group, had no significant difference in terms of cecal intubation rate (96.0% vs 97.0%, P = 0.40) and time (9.94 ± 7.05 min vs 10.34 ± 6.82 min, P = 0.21), or polyp detection rate (32.8% vs 31.3%, P = 0.75). On the subgroup analysis, there was no significant difference in terms of cecal intubation time by trainees (88.1% vs 84.8%, P = 0.40), ileal intubation rate (82.5% vs 79.0%, P = 0.38) or total colonoscopy time (23.24 ± 13.95 min vs 22.56 ± 9.94 min, P = 0.88). On multivariate analysis, the independent determinants of faster cecal time were consultant-performed procedures (P < 0.001), male patients (P < 0.001), non-usage of hyoscine (P < 0.001) and better bowel preparation (P = 0.01). The determinants of better polyp detection rate were older age (P < 0.001), no history of previous abdominal surgery (P = 0.04), patients not having esophagogastroduodenoscopy in the same setting (P = 0.003), trainee-performed procedures (P = 0.01), usage of hyoscine (P = 0.01) and procedures performed for polyp follow-up (P = 0.01). The limitations of the study were that it was a single-center experience, no blinding was possible, and there were a large number of endoscopists. CONCLUSION: CAC did not significantly different from SC in term of cecal intubation time and polyp detection rate. PMID:20712051

  8. Real-time differentiation of adenomatous and hyperplastic diminutive colorectal polyps during analysis of unaltered videos of standard colonoscopy using a deep learning model.

    PubMed

    Byrne, Michael F; Chapados, Nicolas; Soudan, Florian; Oertel, Clemens; Linares Pérez, Milagros; Kelly, Raymond; Iqbal, Nadeem; Chandelier, Florent; Rex, Douglas K

    2017-10-24

    In general, academic but not community endoscopists have demonstrated adequate endoscopic differentiation accuracy to make the 'resect and discard' paradigm for diminutive colorectal polyps workable. Computer analysis of video could potentially eliminate the obstacle of interobserver variability in endoscopic polyp interpretation and enable widespread acceptance of 'resect and discard'. We developed an artificial intelligence (AI) model for real-time assessment of endoscopic video images of colorectal polyps. A deep convolutional neural network model was used. Only narrow band imaging video frames were used, split equally between relevant multiclasses. Unaltered videos from routine exams not specifically designed or adapted for AI classification were used to train and validate the model. The model was tested on a separate series of 125 videos of consecutively encountered diminutive polyps that were proven to be adenomas or hyperplastic polyps. The AI model works with a confidence mechanism and did not generate sufficient confidence to predict the histology of 19 polyps in the test set, representing 15% of the polyps. For the remaining 106 diminutive polyps, the accuracy of the model was 94% (95% CI 86% to 97%), the sensitivity for identification of adenomas was 98% (95% CI 92% to 100%), specificity was 83% (95% CI 67% to 93%), negative predictive value 97% and positive predictive value 90%. An AI model trained on endoscopic video can differentiate diminutive adenomas from hyperplastic polyps with high accuracy. Additional study of this programme in a live patient clinical trial setting to address resect and discard is planned. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  9. Polyp detection rates using magnification with narrow band imaging and white light.

    PubMed

    Gilani, Nooman; Stipho, Sally; Panetta, James D; Petre, Sorin; Young, Michele A; Ramirez, Francisco C

    2015-05-16

    To compare the yield of adenomas between narrow band imaging and white light when using high definition/magnification. This prospective, non-randomized comparative study was performed at the endoscopy unit of veteran affairs medical center in Phoenix, Arizona. Consecutive patients undergoing first average risk colorectal cancer screening colonoscopy were selected. Two experienced gastroenterologists performed all the procedures that were blinded to each other's findings. Demographic details were recorded. Data are presented as mean ± SEM. Proportional data were compared using the χ(2) test and means were compared using the Student's t test. Tandem colonoscopy was performed in a sequential and segmental fashion using one of 3 strategies: white light followed by narrow band imaging [Group A: white light (WL) → narrow band imaging (NBI)]; narrow band imaging followed by white light (Group B: NBI → WL) and, white light followed by white light (Group C: WL → WL). Detection rate of missed polyps and adenomas were evaluated in all three groups. Three hundred patients were studied (100 in each Group). Although the total time for the colonoscopy was similar in the 3 groups (23.8 ± 0.7, 22.2 ± 0.5 and 24.1 ± 0.7 min for Groups A, B and C, respectively), it reached statistical significance between Groups B and C (P < 0.05). The cecal intubation time in Groups B and C was longer than for Group A (6.5 ± 0.4 min and 6.5 ± 0.4 min vs 4.9 ± 0.3 min; P < 0.05). The withdrawal time for Groups A and C was longer than Group B (18.9 ± 0.7 min and 17.6 ± 0.6 min vs 15.7 ± 0.4 min; P < 0.05). Overall miss rate for polyps and adenomas detected in three groups during the second look was 18% and 17%, respectively (P = NS). Detection rate for polyps and adenomas after first look with white light was similar irrespective of the light used during the second look (WL → WL: 13.7% for polyps, 12.6% for adenomas; WL → NBI: 14.2% for polyps, 11.3% for adenomas). Miss rate of polyps and adenomas however was significantly higher when NBI was used first (29.3% and 30.3%, respectively; P < 0.05). Most missed adenomas were ≤ 5 mm in size. There was only one advanced neoplasia (defined by size only) missed during the first look. Our data suggest that the tandem nature of the procedure rather than the optical techniques was associated with the detection of additional polyps' and adenomas.

  10. Hyoscine butylbromide for colorectal polyp detection: prospective, randomized, placebo-controlled trial

    PubMed Central

    dos Santos, Carlos Eduardo Oliveira; Moreira, Hamilton; Pereira-Lima, Julio Carlos; Ribas, Carmen Australia Paredes Marcondes; de Quadros Onófrio, Fernanda; Czecko, Alexandre Eduardo Augusti; Ramos, Rafael Koerich; de Carvalho, Caroline Aragão

    2017-01-01

    OBJECTIVES: The removal of pre-malignant colorectal lesions prevents cancer. Hyoscine has been proposed as a means of improving diagnosis by reducing colonic movements. The aim of this study was to analyze whether this anti-spasmodic enhances the detection of pre-malignant colorectal lesions. METHODS: In a randomized, double-blinded fashion patients received hyoscine or a saline solution in all consecutive colonoscopies in which the cecum was reached. Lesions were analysed with respect to number, size, location, histology and capillary pattern. RESULTS: A total of 440 colonoscopies were randomized. The overall polyp detection rate (PDR) and the adenoma detection rate (ADR) were 65.2% and 49.3%, respectively. In the hyoscine group, non-polypoid lesions were detected significantly more often (p=0.01). In the placebo group 281 lesions were diagnosed (202 adenomas) and in the hyoscine group 282 lesions were detected (189 adenomas) (p=0.23). The PDR and ADR were similar between the placebo and hyoscine groups (64% vs 66% and 50% vs 47%, respectively). No differences were observed between the two groups in the advanced-ADR or advanced neoplasia detection rate, as well the mean numbers of polyps, adenomas, advanced adenomas and advanced neoplasias detected per patient. The administration of hyoscine also did not improve the diagnostic accuracy of digital chromoendoscopy. The presence of adenomatous polyps in the right colon was detected significantly more frequently in the hyoscine group (OR 5.41 95% CI 2.7 - 11; p<0.01 vs OR 2.3 95% CI 1.1 - 4.6; p=0.02). CONCLUSION: The use of hyoscine before beginning the withdrawal of the colonoscope does not seem to enhance the PDR and the ADR. PMID:28792997

  11. Hyoscine butylbromide for colorectal polyp detection: prospective, randomized, placebo-controlled trial.

    PubMed

    Dos Santos, Carlos Eduardo Oliveira; Moreira, Hamilton; Pereira-Lima, Julio Carlos; Ribas, Carmen Australia Paredes Marcondes; de Quadros Onófrio, Fernanda; Czecko, Alexandre Eduardo Augusti; Ramos, Rafael Koerich; de Carvalho, Caroline Aragão

    2017-07-01

    The removal of pre-malignant colorectal lesions prevents cancer. Hyoscine has been proposed as a means of improving diagnosis by reducing colonic movements. The aim of this study was to analyze whether this anti-spasmodic enhances the detection of pre-malignant colorectal lesions. In a randomized, double-blinded fashion patients received hyoscine or a saline solution in all consecutive colonoscopies in which the cecum was reached. Lesions were analysed with respect to number, size, location, histology and capillary pattern. A total of 440 colonoscopies were randomized. The overall polyp detection rate (PDR) and the adenoma detection rate (ADR) were 65.2% and 49.3%, respectively. In the hyoscine group, non-polypoid lesions were detected significantly more often (p=0.01). In the placebo group 281 lesions were diagnosed (202 adenomas) and in the hyoscine group 282 lesions were detected (189 adenomas) (p=0.23). The PDR and ADR were similar between the placebo and hyoscine groups (64% vs 66% and 50% vs 47%, respectively). No differences were observed between the two groups in the advanced-ADR or advanced neoplasia detection rate, as well the mean numbers of polyps, adenomas, advanced adenomas and advanced neoplasias detected per patient. The administration of hyoscine also did not improve the diagnostic accuracy of digital chromoendoscopy. The presence of adenomatous polyps in the right colon was detected significantly more frequently in the hyoscine group (OR 5.41 95% CI 2.7 - 11; p<0.01 vs OR 2.3 95% CI 1.1 - 4.6; p=0.02). The use of hyoscine before beginning the withdrawal of the colonoscope does not seem to enhance the PDR and the ADR.

  12. A multi-mineral natural product from red marine algae reduces colon polyp formation in C57BL/6 mice

    PubMed Central

    Aslam, Muhammad N.; Bergin, Ingrid; Naik, Madhav; Paruchuri, Tejaswi; Hampton, Anna; Rehman, Muneeb; Dame, Michael K; Rush, Howard; Varani, James

    2013-01-01

    The goal of this study was to determine if a multi-mineral natural product derived from red marine algae, could reduce colon polyp formation in mice on a high fat diet. C57BL/6 mice were maintained for up to 18 months either on a high-fat “Western-style” diet or on a low-fat diet (AIN 76A), with or without the multi-mineral-supplement. To summarize, colon polyps were detected in 22 of 70 mice (31%) on the high-fat diet, but in only 2 of 70 mice (3%) receiving the mineral-supplemented high-fat diet (p<0.0001). Colon polyps were detected in 16 of 70 mice (23%) in the low-fat group; not significantly different from high-fat group but significantly higher than the high-fat-supplemented group (p=0.0006). This was in spite of the fact that the calcium level in the low-fat diet was comparable to the level of calcium in the high-fat diet containing the multi-mineral-product. Supplementation of the low-fat diet reduced the incidence to 8 of 70 mice (11% incidence). Taken together, these findings demonstrate that a multi-mineral natural product can protect mice on a high-fat diet against adenomatous polyp formation in the colon. These data suggest that increased calcium alone is insufficient to explain the lower incidence of colon polyps. PMID:23035966

  13. New Insights into the in situ Microscopic Visualization and Quantification of Inorganic Polyphosphate Stores by 4’,6-Diamidino-2-Phenylindole (DAPI)-Staining

    PubMed Central

    Gomes, F.M.; Ramos, I.B.; Wendt, C.; Girard-Dias, W.; De Souza, W.; Machado, E.A.; K. Miranda, E.A.

    2013-01-01

    Inorganic polyphosphate (PolyP) is a biological polymer that plays important roles in the cell physiology of both prokaryotic and eukaryotic organisms. Among the available methods for PolyP localization and quantification, a 4’,6-diamidino-2-phenylindole(DAPI)-based assay has been used for visualization of PolyP-rich organelles. Due to differences in DAPI permeability to different compartments and/or PolyP retention after fixation, a general protocol for DAPI-PolyP staining has not yet been established. Here, we tested different protocols for DAPI-PolyP detection in a range of samples with different levels of DAPI permeability, including subcellular fractions, free-living cells and cryosections of fixed tissues. Subcellular fractions of PolyP-rich organelles yielded DAPI-PolyP fluorescence, although those with a complex external layer usually required longer incubation times, previous aldehyde fixation and/or detergent permeabilization. DAPI-PolyP was also detected in cryosections of OCT-embedded tissues analyzed by multiphoton microscopy. In addition, a semi-quantitative fluorimetric analysis of DAPI-stained fractions showed PolyP mobilization in a similar fashion to what has been demonstrated with the use of enzyme-based quantitative protocols. Taken together, our results support the use of DAPI for both PolyP visualization and quantification, although specific steps are suggested as a general guideline for DAPI-PolyP staining in biological samples with different degrees of DAPI and PolyP permeability. PMID:24441187

  14. Real-Time Optical Biopsy of Colon Polyps With Narrow Band Imaging in Community Practice Does Not Yet Meet Key Thresholds for Clinical Decisions

    PubMed Central

    LADABAUM, URI; FIORITTO, ANN; MITANI, AYA; DESAI, MANISHA; KIM, JANE P.; REX, DOUGLAS K.; IMPERIALE, THOMAS; GUNARATNAM, NARESH

    2017-01-01

    BACKGROUND & AIMS Accurate optical analysis of colorectal polyps (optical biopsy) could prevent unnecessary polypectomies or allow a “resect and discard” strategy with surveillance intervals determined based on the results of the optical biopsy; this could be less expensive than histopathologic analysis of polyps. We prospectively evaluated real-time optical biopsy analysis of polyps with narrow band imaging (NBI) by community-based gastroenterologists. METHODS We first analyzed a computerized module to train gastroenterologists (N = 13) in optical biopsy skills using photographs of polyps. Then we evaluated a practice-based learning program for these gastroenterologists (n = 12) that included real-time optical analysis of polyps in vivo, comparison of optical biopsy predictions to histopathologic analysis, and ongoing feedback on performance. RESULTS Twelve of 13 subjects identified adenomas with >90% accuracy at the end of the computer study, and 3 of 12 subjects did so with accuracy ≥90% in the in vivo study. Learning curves showed considerable variation among batches of polyps. For diminutive rectosigmoid polyps assessed with high confidence at the end of the study, adenomas were identified with mean (95% confidence interval [CI]) accuracy, sensitivity, specificity, and negative predictive values of 81% (73%–89%), 85% (74%–96%), 78% (66%–92%), and 91% (86%–97%), respectively. The adjusted odds ratio for high confidence as a predictor of accuracy was 1.8 (95% CI, 1.3–2.5). The agreement between surveillance recommendations informed by high-confidence NBI analysis of diminutive polyps and results from histopathologic analysis of all polyps was 80% (95% CI, 77%–82%). CONCLUSIONS In an evaluation of real-time optical biopsy analysis of polyps with NBI, only 25% of gastroenterologists assessed polyps with ≥90% accuracy. The negative predictive value for identification of adenomas, but not the surveillance interval agreement, met the American Society for Gastrointestinal Endoscopy–recommended thresholds for optical biopsy. Better results in community practice must be achieved before NBI-based optical biopsy methods can be used routinely to evaluate polyps; ClinicalTrials.gov number, NCT01638091. PMID:23041328

  15. Comparison of hand-craft feature based SVM and CNN based deep learning framework for automatic polyp classification.

    PubMed

    Younghak Shin; Balasingham, Ilangko

    2017-07-01

    Colonoscopy is a standard method for screening polyps by highly trained physicians. Miss-detected polyps in colonoscopy are potential risk factor for colorectal cancer. In this study, we investigate an automatic polyp classification framework. We aim to compare two different approaches named hand-craft feature method and convolutional neural network (CNN) based deep learning method. Combined shape and color features are used for hand craft feature extraction and support vector machine (SVM) method is adopted for classification. For CNN approach, three convolution and pooling based deep learning framework is used for classification purpose. The proposed framework is evaluated using three public polyp databases. From the experimental results, we have shown that the CNN based deep learning framework shows better classification performance than the hand-craft feature based methods. It achieves over 90% of classification accuracy, sensitivity, specificity and precision.

  16. The Influence of Screening for Precancerous Lesions on Family-Based Genetic Association Tests: An Example of Colorectal Polyps and Cancer.

    PubMed

    Schmit, Stephanie L; Figueiredo, Jane C; Cortessis, Victoria K; Thomas, Duncan C

    2015-10-15

    Unintended consequences of secondary prevention include potential introduction of bias into epidemiologic studies estimating genotype-disease associations. To better understand such bias, we simulated a family-based study of colorectal cancer (CRC), which can be prevented by resecting screen-detected polyps. We simulated genes related to CRC development through risk of polyps (G1), risk of CRC but not polyps (G2), and progression from polyp to CRC (G3). Then, we examined 4 analytical strategies for studying diseases subject to secondary prevention, comparing the following: 1) CRC cases with all controls, without adjusting for polyp history; 2) CRC cases with controls, adjusting for polyp history; 3) CRC cases with only polyp-free controls; and 4) cases with either CRC or polyps with controls having neither. Strategy 1 yielded estimates of association between CRC and each G that were not substantially biased. Strategies 2-4 yielded biased estimates varying in direction according to analysis strategy and gene type. Type I errors were correct, but strategy 1 provided greater power for estimating associations with G2 and G3. We also applied each strategy to case-control data from the Colon Cancer Family Registry (1997-2007). Generally, the best analytical option balancing bias and power is to compare all CRC cases with all controls, ignoring polyps. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Colonoscopy audit over 10 years--what can be learnt?

    PubMed

    Fraser, Alan G; Gamble, Greg D; Rose, Toby R; Dunn, John P

    2013-09-13

    The goals of colonoscopy are changing over time and it is important to regularly determine if endoscopists are achieving key performance indicators. Data on key performance indicators were recorded independently by nursing staff for all colonoscopies performed during a 10-year period. The results were discussed at regular meetings and feedback given to endoscopists. Audit data was recorded for 67,570 procedures. The key performance indicators (time to caecum, withdrawal time, adjusted caecal intubation rate and polyp detection rate) all improved over the audit period (p<0.0001 for trend). For each endoscopist the mean withdrawal time was highly variable ranging from 3.1 mins (95%CI 3.0; 3.1) to 11.2 mins (11.0; 11.3). For each endoscopist mean polyp detection rate varied from 29% (CI 26, 31%) to 69% (CI 68, 70%). There was a significant correlation between mean withdrawal time and mean polyp detection rate for each endoscopist (r=0.42; p=0.03). The polyp detection rate improved from 29% in 1999 to 49% in 2010. The proportion of procedures with more than 2 polyps increased from 22% in 2001 to 33% in 2010. There was a significant association of patient discomfort with time to caecum and also to level of consciousness, p<0.0001. There was a significant decrease in the proportion with significant discomfort over the audit period, p<0.0001. Colonoscopy audit as a routine process with data collection by endoscopy nurses over several years may be able to improve key performance indicators by the process of regular feedback to endoscopists. Audit should be encouraged as a routine process rather than simply as a research tool for a limited period.

  18. National CT Colonography Trial (ACRIN 6664): Comparison of Three Full-Laxative Bowel Preparations in More Than 2500 Average-Risk Patients

    PubMed Central

    Hara, Amy K.; Kuo, Mark D.; Blevins, Meridith; Chen, Mei-Hsiu; Yee, Judy; Dachman, Abraham; Menias, Christine O.; Siewert, Betina; Cheema, Jugesh I.; Obregon, Richard G.; Fidler, Jeff L.; Zimmerman, Peter; Horton, Karen M.; Coakley, Kevin; Iyer, Revathy B.; Halvorsen, Robert A.; Casola, Giovanna; Johnson, C. Daniel

    2011-01-01

    OBJECTIVE The purpose of our study was to compare the effect of three different full-laxative bowel preparations on patient compliance, residual stool and fluid, reader confidence, and polyp detection at CT colonography (CTC). SUBJECTS AND METHODS A total of 2531 patients underwent CTC followed by colonoscopy for the American College of Radiology Imaging Network (ACRIN) National CTC Trial. Of this total, 2525 patients used one of three bowel preparations with bisacodyl tablets and stool and fluid tagging: 4 L of polyethylene glycol (PEG); 90 mL of phosphosoda; or 300 mL of magnesium citrate. Patients reported percent compliance with the bowel preparation and radiologists graded each CTC examination for the amount of residual fluid and stool on a scale from 1 (none) to 4 (nondiagnostic). Reader confidence for true-positive findings was reported on a 5-point scale: 1 (low) to 5 (high). Sensitivity and specificity for detecting polyps ≥ 6 mm and ≥ 1 cm compared with colonoscopy were calculated for each preparation. RESULTS The most commonly prescribed preparation was phosphosoda (n = 1403) followed by PEG (n = 1020) and magnesium citrate (n = 102). Phosphosoda had the highest patient compliance (p = 0.01), least residual stool (p < 0.001), and highest reader confidence versus PEG for examinations with polyps (p = 0.06). Magnesium citrate had significantly more residual fluid compared with PEG and phosphosoda (p = 0.006). The sensitivity and specificity for detecting colon polyps ≥ 6 mm and ≥ 1 cm did not differ significantly between preparations. CONCLUSION Polyp detection was comparable for all three preparations, although phosphosoda had significantly higher patient compliance and the least residual stool. PMID:21512073

  19. Application of laser-induced autofluorescence spectra detection system in human colorectal cancer in-vivo screening

    NASA Astrophysics Data System (ADS)

    Chia, Teck Chee; Fu, Sheng; Chia, Yee Hong; Kwek, Leong Chuan; Tang, Choong Leong

    2005-09-01

    This study aimed at applying Laser induced-autofluorescence (LIAF) diagnostics method as an in-vivo screening of colorectal polyplcancer. The spectrum algorithm based on the ratio of autofluorescence intensity was used to identify the diseased tissues from the normal tissues as it was generally performed better than an algorithm based only simply on the intensity of the spectrum. Histopathological biopsy results were compared with the detected AF spectra characteristics for different kinds of polyps. 73 patients had been examined via the LIAF spectroscopy detection system during their colonoscopy screening in Endoscopy Center, Singapore General Hospital. The autofluorescence from the surface of the colorectal tissues under 405 nm laser light excitation was detected using our detecting system. In the experimental investigation two groups of patients were involved. One group was "abnormal" group. There were 25 patients belonging to this group since polyps or carcinoma was found in their colorectal tract during colonoscopy. The histopathology reports confirm the group classification. Total 36 polyps' AF spectra and 9 carcinoma' AF spectra were detected from 25 patients of the abnormal group during their regular endoscopy examination. The intensity ratios RI-680/I-500 and RI-630/I-500 of polyps/cancerous AF spectra and intensity ratios of corresponding normal colorectal AF spectra were calculated. Two critical intensity ratios for separating the AF intensity ratios RI-680/I-500 and RI-630/I-500 of normal and abnormal colorectal tissues were defined as 0.5 and 0.6 respectively. Using the critical intensity ratio values, 48 "normal" group patients' rectums were checked via the LIAF detection system. There were 20 patients (41.7%) whose AF spectra of colorectal tract mucosa belonging to abnormal spectra. However, these 20 patients had not been found under white light via traditional endoscopy. For small diseased area like small plat polyp disease and carcinoma, it was very difficult to identify under white light by endoscopy. However, the LIAF spectra technique and AF intensity ratio algorithm was able to detect these kinds of abnormal area earlier than traditional endoscopy. Using this algorithm, it is able to identify the onset of abnormal tissue growth during real-time clinical endoscope examination.

  20. Assessment of an Optical Flow Field-Based Polyp Detector for CT Colonography

    DTIC Science & Technology

    2001-10-25

    sort true polyps from false positives based on features extracted from the computed OFFs. II. METHODOLOGY A. Pre-processing The 3D CT data was...subvolume and scrolling direction, as follows:      = ∑ Z ZD y)x,( Smoothy )x,( vv (2) The smoothing filter used is a 3×3 rectangular

  1. Prolapsing Gastric Polyp Causing Intermittent Gastric Outlet Obstruction.

    PubMed

    Kosai, Nik Ritza; Gendeh, Hardip Singh; Norfaezan, Abdul Rashid; Razman, Jamin; Sutton, Paul Anthony; Das, Srijit

    2015-06-01

    Gastric polyps are often an incidental finding on upper gastrointestinal endoscopy, with an incidence up to 5%. The majority of gastric polyps are asymptomatic, occurring secondary to inflammation. Prior reviews discussed Helicobacter pylori (H pylori)-associated singular gastric polyposis; however, we present a rare and unusual case of recurrent multiple benign gastric polyposis post H pylori eradication resulting in intermittent gastric outlet obstruction. A 70-year-old independent male, Chinese in ethnicity, with a background of diabetes mellitus, hypertension, and a simple renal cyst presented with a combination of melena, anemia, and intermittent vomiting of partially digested food after meals. Initial gastroscopy was positive for H pylori; thus he was treated with H pylori eradication and proton pump inhibitors. Serial gastroscopy demonstrated multiple sessile gastric antral polyps, the largest measuring 4 cm. Histopathologic examination confirmed a benign hyperplastic lesion. Computed tomography identified a pyloric mass with absent surrounding infiltration or metastasis. A distal gastrectomy was performed, whereby multiple small pyloric polyps were found, the largest prolapsing into the pyloric opening, thus explaining the intermittent nature of gastric outlet obstruction. Such polyps often develop from gastric ulcers and, if left untreated, may undergo neoplasia to form malignant cells. A distal gastrectomy was an effective choice of treatment, taking into account the polyp size, quantity, and potential for malignancy as opposed to an endoscopic approach, which may not guarantee a complete removal of safer margins and depth. Therefore, surgical excision is favorable for multiple large gastric polyps with risk of malignancy.

  2. Prolapsing Gastric Polyp Causing Intermittent Gastric Outlet Obstruction

    PubMed Central

    Kosai, Nik Ritza; Gendeh, Hardip Singh; Norfaezan, Abdul Rashid; Razman, Jamin; Sutton, Paul Anthony; Das, Srijit

    2015-01-01

    Gastric polyps are often an incidental finding on upper gastrointestinal endoscopy, with an incidence up to 5%. The majority of gastric polyps are asymptomatic, occurring secondary to inflammation. Prior reviews discussed Helicobacter pylori (H pylori)–associated singular gastric polyposis; however, we present a rare and unusual case of recurrent multiple benign gastric polyposis post H pylori eradication resulting in intermittent gastric outlet obstruction. A 70-year-old independent male, Chinese in ethnicity, with a background of diabetes mellitus, hypertension, and a simple renal cyst presented with a combination of melena, anemia, and intermittent vomiting of partially digested food after meals. Initial gastroscopy was positive for H pylori; thus he was treated with H pylori eradication and proton pump inhibitors. Serial gastroscopy demonstrated multiple sessile gastric antral polyps, the largest measuring 4 cm. Histopathologic examination confirmed a benign hyperplastic lesion. Computed tomography identified a pyloric mass with absent surrounding infiltration or metastasis. A distal gastrectomy was performed, whereby multiple small pyloric polyps were found, the largest prolapsing into the pyloric opening, thus explaining the intermittent nature of gastric outlet obstruction. Such polyps often develop from gastric ulcers and, if left untreated, may undergo neoplasia to form malignant cells. A distal gastrectomy was an effective choice of treatment, taking into account the polyp size, quantity, and potential for malignancy as opposed to an endoscopic approach, which may not guarantee a complete removal of safer margins and depth. Therefore, surgical excision is favorable for multiple large gastric polyps with risk of malignancy. PMID:25578789

  3. Management and follow-up of gallbladder polyps : Joint guidelines between the European Society of Gastrointestinal and Abdominal Radiology (ESGAR), European Association for Endoscopic Surgery and other Interventional Techniques (EAES), International Society of Digestive Surgery - European Federation (EFISDS) and European Society of Gastrointestinal Endoscopy (ESGE).

    PubMed

    Wiles, Rebecca; Thoeni, Ruedi F; Barbu, Sorin Traian; Vashist, Yogesh K; Rafaelsen, Søren Rafael; Dewhurst, Catherine; Arvanitakis, Marianna; Lahaye, Max; Soltes, Marek; Perinel, Julie; Roberts, Stuart Ashley

    2017-09-01

    The management of incidentally detected gallbladder polyps on radiological examinations is contentious. The incidental radiological finding of a gallbladder polyp can therefore be problematic for the radiologist and the clinician who referred the patient for the radiological examination. To address this a joint guideline was created by the European Society of Gastrointestinal and Abdominal Radiology (ESGAR), European Association for Endoscopic Surgery and other Interventional Techniques (EAES), International Society of Digestive Surgery - European Federation (EFISDS) and European Society of Gastrointestinal Endoscopy (ESGE). A targeted literature search was performed and consensus guidelines were created using a series of Delphi questionnaires and a seven-point Likert scale. A total of three Delphi rounds were performed. Consensus regarding which patients should have cholecystectomy, which patients should have ultrasound follow-up and the nature and duration of that follow-up was established. The full recommendations as well as a summary algorithm are provided. These expert consensus recommendations can be used as guidance when a gallbladder polyp is encountered in clinical practice. • Management of gallbladder polyps is contentious • Cholecystectomy is recommended for gallbladder polyps >10 mm • Management of polyps <10 mm depends on patient and polyp characteristics • Further research is required to determine optimal management of gallbladder polyps.

  4. Individual polyp detection rate in routine daily endoscopy practice depends on case-mix.

    PubMed

    Loffeld, R J L F; Liberov, B; Dekkers, P E P

    2015-07-01

    The adenoma detection rate (ADR), a marker of endoscopic quality, is confounded by selection bias. It is not known what the ADR is in normal daily practice. To study the polyp detection rate (PDR) in different endoscopists in the course of years. All consecutive endoscopies of the colon done in 11 years were included. Endoscopies in the regular surveillance programme after polyp removal and after surgery because of colorectal cancer or diverticular disease were scored separately. The number of yearly procedures per endoscopist and presence of polyps, anastomoses, surveillance and cancer were noted. In the period of 11 years, 14,908 consecutive endoscopies of colon and rectum were done by four endoscopists. Two endoscopists had a significantly lower PDR than the other two (p < 0.001), these two had the longest careers in endoscopy. The two younger endoscopists did significantly less often procedures in patients with anastomoses and because of surveillance (p < 0.001, respectively). One endoscopist detected significantly less colorectal cancers than the other three endoscopists (p < 0.001). This study presents the PDR in normal routine daily endoscopy practice. It can be concluded that the PDR, implicating the ADR, in unselected patients can be lower in individual endoscopists than recommended in the literature. This highly depends on the case-mix of patients presented for endoscopy. This result debates the use of the ADR as quality indicator for individual endoscopists.

  5. High-definition colonoscopy increases adenoma detection rate.

    PubMed

    Jrebi, Nezar Y; Hefty, Matthew; Jalouta, Tarek; Ogilvie, James; Davis, Alan T; Asgeirsson, Theodor; Luchtefeld, Martin

    2017-01-01

    The adenoma detection rate (ADR) is a quality indicator for colonoscopy. High-definition (HD) imaging has been reported to increase polyp detection rates. The primary objective of this study was to compare polyp detection rate (PDR) and adenoma detection rate (ADR) before and after the implementation of HD colonoscopy. A retrospective chart review was performed on patients aged 48-55 years old, who underwent first-time screening colonoscopy. The first group underwent standard-definition (SD) colonoscopy in the first 6 months of 2011. The second group underwent screening with HD colonoscopy during the first 6 months of 2012. We compared age, gender, PDR, ADR, and average sizes of adenomatous polyps between gastroenterologist and colorectal surgeon and among physicians themselves. Statistical analysis was performed with Fischer's exact test and Pearson Chi-square. A total of 1268 patients were involved in the study (634 in each group). PDR (35.6 vs. 48.2 %, p < 0.001) and ADR (22.2 vs. 30.4 %, p = 0.02) were higher in the HD group. The average size of an adenomatous polyp was the same in the two groups (0.58 vs. 0.57, p = 0.69). However, this difference was not seen among colorectal surgeons PDR (35.7 vs. 37 %, p = 0.789), ADR (22.9 vs. 24.5 % p = 0.513), but clearly seen among gastroenterologist, PDR (35.6 vs. 53.1 % p < 0.001) and ADR (21.9 vs. 32.9 % p < 0.001). When polyps were categorized into size groups, there was no difference in ADR between the two timeframes (<5 mm in size (41.5 vs. 35.4 %), 5-10 mm (49.3 vs. 60.1 %) and >10 mm (9.2 vs. 4.5 %), p = 0.07). Polyps were most commonly seen in the sigmoid colon (26.1 vs. 24.7 %). There was no difference in the rate of synchronous polyp detection between modalities (25.6 vs. 29 %, p = 0.51). Withdrawal time was the same in both procedure (9.2 vs. 8.5 min, p = 0.10). Screening colonoscopy with high-definition technology significantly improved both PDR and ADR. In addition, high-definition colonoscopy may be particularly useful and advantageous among less experienced endoscopists in various community settings. However, there needs to be application to specific patient populations in future studies to assess for any statistical differences between standard- and high-definition modalities to determine clinical utility.

  6. The natural history of endometrial polyps.

    PubMed

    Wong, M; Crnobrnja, B; Liberale, V; Dharmarajah, K; Widschwendter, M; Jurkovic, D

    2017-02-01

    What is the natural history of endometrial polyps in women who are managed expectantly? The growth rates of expectantly managed polyps vary considerably and cannot be accurately predicted. The majority of polyps detected on ultrasound are treated surgically, and therefore little is known about their natural history. Some polyps have been reported to regress spontaneously without the need for treatment; however, the factors predictive of regression are unknown. This was a retrospective cohort study conducted at the Department of Gynaecology, University College London Hospitals. We searched our ultrasound clinic database between July 1997 and September 2015, to identify women aged 18 years or older with endometrial polyps that were managed expectantly for ≥6 months. All women attended for a minimum of two ultrasound scans. A single expert operator performed all ultrasound scans. Those with <6-month follow-up and those who were taking hormonal contraception, HRT or tamoxifen were excluded from the study. The mean diameter of each polyp was calculated from the measurements in three perpendicular planes. The polyp growth rate was expressed as annual percentage change in the mean diameter. Non-parametric tests and the Fisher's exact test were used to compare differences in polyp mean diameters and growth rates between women of different demographic characteristics. To correct for multiple significance testing, we used the Bonferroni method, giving the level of probability at which findings were considered significant as P < 0.0029 (as 17 tests were undertaken). We included 112 women with endometrial polyps, which were expectantly managed over a median period of 22.5 months (range, 6-136). The annual endometrial polyp growth rate varied with a median of 1.0% (interquartile range, -6.5 to 14.3). There was no association between women's demographic characteristics or polyps' morphology and their growth rates. Eleven out of 75 (15% (95% CI, 6.9%-23.1%)) women who initially did not have abnormal uterine bleeding subsequently developed abnormal bleeding during the follow-up period. Polyp growth rate was not associated with the subsequent development of abnormal uterine bleeding (P = 0.397). Seven out of 112 (6.3% (95% CI, 1.8%-10.8%)) women had complete regression of their polyps without treatment during a median follow-up period of 28 months (range, 9-56). Spontaneous regression appeared to occur more frequently in premenopausal women (P = 0.016) and in those who presented with abnormal uterine bleeding at diagnosis (P = 0.004); however, the differences did not reach statistical significance after correction for multiple comparisons. This study was retrospective and therefore may be prone to selection and information biases. The lack of histological confirmation on all ultrasound diagnoses may also be considered as a limitation. Women should be advised that the growth pattern of an individual polyp cannot be accurately predicted; however, a small proportion of polyps do regress spontaneously. There was no correlation between polyps' growth rate and the subsequent development of abnormal uterine bleeding. In view of that, routine monitoring of asymptomatic polyps by ultrasound is not helpful and encouraging women to report clinical symptoms is more useful in deciding whether treatment is required. In contrast to previous studies, we found that polyps may regress more frequently in premenopausal women and in those who presented with abnormal uterine bleeding; a larger sample size would give us greater power to detect a difference in these subgroups of women. No study funding was received and no competing interests are present. N/A. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Gastric Polyp Growth during Endoscopic Surveillance for Esophageal Varices or Barrett's Esophagus.

    PubMed

    Livovsky, Dan M; Pappo, Orit; Skarzhinsky, Galina; Peretz, Asaf; Turvall, Elliot; Ackerman, Zvi

    2016-05-01

    We recently observed patients with chronic liver disease (CLD) or chronic reflux symptoms (CRS) who developed gastric polyps (GPs) while undergoing surveillance gastroscopies for the detection of esophageal varices or Barrett's esophagus, respectively. To identify risk factors for GP growth and estimate its growth rate. GP growth rate was defined as the number of days since the first gastroscopy (without polyps) in the surveillance program, until the gastroscopy when a GP was discovered. Gastric polyp growth rates in CLD and CRS patients were similar. However, hyperplastic gastric polyps (HGPs) were detected more often (87.5% vs. 60.5%, P = 0.051) and at a higher number (2.57 ± 1.33 vs. 1.65 ± 0.93, P = 0.021) in the CLD patients. Subgroup analysis revealed the following findings only in CLD patients with HGPs: (i) a positive correlation between the GP growth rate and the patient's age; the older the patient, the higher the GP growth rate (r = 0.7, P = 0.004). (ii) A negative correlation between the patient's age and the Ki-67 proliferation index value; the older the patient, the lower the Ki-67 value (r = -0.64, P = 0.02). No correlation was detected between Ki-67 values of HGPs in CLD patients and the presence of portal hypertension, infection with Helicobacter pylori, or proton pump inhibitor use. In comparison with CRS patients, CLD patients developed HGPs more often and at a greater number. Young CLD patients may have a tendency to develop HGPs at a faster rate than elderly CLD patients.

  8. Randomized, controlled trial of standard, large-capacity versus jumbo biopsy forceps for polypectomy of small, sessile, colorectal polyps.

    PubMed

    Draganov, Peter V; Chang, Myron N; Alkhasawneh, Ahmad; Dixon, Lisa R; Lieb, John; Moshiree, Baharak; Polyak, Steven; Sultan, Shahnaz; Collins, Dennis; Suman, Amitabh; Valentine, John F; Wagh, Mihir S; Habashi, Samir L; Forsmark, Chris E

    2012-01-01

    Polypectomy with cold biopsy forceps is a frequently used technique for removal of small, sessile, colorectal polyps. Jumbo forceps may lead to more effective polypectomy because of the larger size of the forceps cup. To evaluate the efficiency of cold jumbo biopsy forceps compared with standard forceps for polypectomy of small, sessile, colorectal polyps. Randomized, controlled trial. Outpatient endoscopy center. This study involved 140 patients found to have at least one eligible polyp defined as a sessile polyp measuring ≤6 mm. Polypectomy with cold biopsy forceps. Complete visual polyp eradication with one forceps bite. In 140 patients, a total of 305 eligible polyps were detected (151 removed with jumbo forceps and 154 with standard forceps). Complete visual eradication of the polyp with one forceps bite was achieved in 78.8% of the jumbo forceps group and 50.7% of the standard forceps group (P < .0001). Biopsies from the polypectomy sites of adenomatous polyps thought to be visually completely eradicated with one bite showed a trend toward a higher complete histologic eradication rate with the jumbo forceps (82.4%) compared with the standard forceps (77.4%), but the difference did not reach statistical significance (P = .62). The withdrawal time for visual inspection of the colon and time to perform polypectomies were significantly shorter in the jumbo forceps group (mean 21.43 vs 18.23 minutes; P = .02). Lack of blinding to the type of forceps used. The jumbo biopsy forceps is superior to the standard forceps in removing small, sessile polyps. ( NCT00855790.). Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  9. Development and validation of a highly sensitive urine-based test to identify patients with colonic adenomatous polyps.

    PubMed

    Wang, Haili; Tso, Victor; Wong, Clarence; Sadowski, Dan; Fedorak, Richard N

    2014-03-20

    Adenomatous polyps are precursors of colorectal cancer; their detection and removal is the goal of colon cancer screening programs. However, fecal-based methods identify patients with adenomatous polyps with low levels of sensitivity. The aim or this study was to develop a highly accurate, prototypic, proof-of-concept, spot urine-based diagnostic test using metabolomic technology to distinguish persons with adenomatous polyps from those without polyps. Prospective urine and stool samples were collected from 876 participants undergoing colonoscopy examination in a colon cancer screening program, from April 2008 to October 2009 at the University of Alberta. Colonoscopy reference standard identified 633 participants with no colonic polyps and 243 with colonic adenomatous polyps. One-dimensional nuclear magnetic resonance spectra of urine metabolites were analyzed to define a diagnostic metabolomic profile for colonic adenomas. A urine metabolomic diagnostic test for colonic adenomatous polyps was established using 67% of the samples (un-blinded training set) and validated using the other 33% of the samples (blinded testing set). The urine metabolomic diagnostic test's specificity and sensitivity were compared with those of fecal-based tests. Using a two-component, orthogonal, partial least-squares model of the metabolomic profile, the un-blinded training set identified patients with colonic adenomatous polyps with 88.9% sensitivity and 50.2% specificity. Validation using the blinded testing set confirmed sensitivity and specificity values of 82.7% and 51.2%, respectively. Sensitivities of fecal-based tests to identify colonic adenomas ranged from 2.5 to 11.9%. We describe a proof-of-concept spot urine-based metabolomic diagnostic test that identifies patients with colonic adenomatous polyps with a greater level of sensitivity (83%) than fecal-based tests.

  10. QuickView video preview software of colon capsule endoscopy: reliability in presenting colorectal polyps as compared to normal mode reading.

    PubMed

    Farnbacher, Michael J; Krause, Horst H; Hagel, Alexander F; Raithel, Martin; Neurath, Markus F; Schneider, Thomas

    2014-03-01

    OBJECTIVE. Colon capsule endoscopy (CCE) proved to be highly sensitive in detection of colorectal polyps (CP). Major limitation is the time-consuming video reading. The aim of this prospective, double-center study was to assess the theoretical time-saving potential and its possible impact on the reliability of "QuickView" (QV), in the presentation of CP as compared to normal mode (NM). METHODS. During NM reading of 65 CCE videos (mean patient´s age 56 years), all frames showing CPs were collected and compared to the number of frames presented by QV at increasing QV settings (10, 20, ... 80%). Reliability of QV in presenting polyps <6 mm and ≥6 mm (significant polyp), and identifying patients for subsequent therapeutic colonoscopy, capsule egestion rate, cleansing level, and estimated time-saving potential were assessed. RESULTS. At a 30% QV setting, the QV video presented 89% of the significant polyps and 86% of any polyps with ≥1 frame (per-polyp analysis) identified in NM before. At a 10% QV setting, 98% of the 52 patients with significant polyps could be identified (per-patient analysis) by QV video analysis. Capsule excretion rate was 74% and colon cleanliness was adequate in 85%. QV´s presentation rate correlates to the QV setting, the polyp size, and the number of frames per finding. CONCLUSIONS. Depending on its setting, the reliability of QV in presenting CP as compared to NM reading is notable. However, if no significant polyp is presented by QV, NM reading must be performed afterwards. The reduction of frames to be analyzed in QV might speed up identification of candidates for therapeutic colonoscopy.

  11. Computer Aided Detection of Breast Masses in Digital Tomosynthesis

    DTIC Science & Technology

    2008-06-01

    the suspicious CAD location were extracted. For the second set, 256x256 ROIs representing the - 8 - summed slab of 5 slices (5 mm) were extracted...region hotelling observer, digital tomosynthesis, multi-slice CAD algorithms, biopsy 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18...developing computer-aided detection ( CAD ) tools for mammography. Although these tools have shown promise in identifying calcifications, detecting

  12. [Colonoscopy for early detection and prevention of colorectal cancer].

    PubMed

    Niv, Yaron

    2010-08-01

    Colonoscopy has a limited success in the prevention of colorectal cancer of the right colon. Thus, there is place for improvement. The potential reasons for colonoscopy failure are the different biology of polyps on the right side of the colon or procedure quality. Preparation, withdrawal time, detection of all polyps and their removal using the best technique will overcome this problem. Furthermore, the implementation of a computerized database and report that includes quality assurance fields, will improve colonoscopy success rates.

  13. Providing data for serrated polyp detection rate benchmarks: an analysis of the New Hampshire Colonoscopy Registry.

    PubMed

    Anderson, Joseph C; Butterly, Lynn F; Weiss, Julia E; Robinson, Christina M

    2017-06-01

    Similar to achieving adenoma detection rate (ADR) benchmarks to prevent colorectal cancer (CRC), achieving adequate serrated polyp detection rates (SDRs) may be essential to the prevention of CRC associated with the serrated pathway. Previous studies have been based on data from high-volume endoscopists at single academic centers. Based on a hypothesis that ADR is correlated with SDR, we stratified a large, diverse group of endoscopists (n = 77 practicing at 28 centers) into high performers and low performers, based on ADR, to provide data for corresponding target SDR benchmarks. By using colonoscopies in adults aged ≥50 years (4/09-12/14), we stratified endoscopists by high and low ADRs (<15%, 15%-<25%, 25%-<35%, ≥35%) to determine corresponding SDRs by using 2 SDR measures, for screening and surveillance colonoscopies separately: (1) Clinically significant SDR (CSSDR), meaning colonoscopies with any sessile serrated adenoma/polyp (SSA/P), traditional serrated adenoma (TSA), or hyperplastic polyp (HP) >1 cm anywhere in the colon or HP >5 mm in the proximal colon only divided by the total number of screening and surveillance colonoscopies, respectively. (2) Proximal SDR (PSDR) meaning colonoscopies with any serrated polyp (SSA/P, HP, TSA) of any size proximal to the sigmoid colon divided by the total number of screening and surveillance colonoscopies, respectively. A total of 45,996 (29,960 screening) colonoscopies by 77 endoscopists (28 facilities) were included. Moderately strong positive correlation coefficients were observed for screening ADR/CSSDR (P = .69) and ADR/PSDR (P = .79) and a strong positive correlation (P = .82) for CSSDR/PSDR (P < .0001 for all) was observed. For ADR ≥25%, endoscopists' median (interquartile range) screening CSSDR was 6.8% (4.3%-8.6%) and PSDR was 10.8% (8.6%-16.1%). Derived from ADR, the primary colonoscopy quality indicator, our results suggest potential SDR benchmarks (CSSDR = 7% and PSDR = 11%) that may guide adequate serrated polyp detection. Because CSSDR and PSDR are strongly correlated, endoscopists could use the simpler PSDR calculation to assess quality. Published by Elsevier Inc.

  14. A study of prostaglandin pathway genes and interactions with current nonsteroidal anti-inflammatory drug use in colorectal adenoma.

    PubMed

    Edwards, Todd L; Shrubsole, Martha J; Cai, Qiuyin; Li, Guoliang; Dai, Qi; Rex, Douglas K; Ulbright, Thomas M; Fu, Zhenming; Murff, Harvey J; Smalley, Walter; Ness, Reid; Zheng, Wei

    2012-06-01

    Colorectal cancer (CRC) is the second leading cause of cancer-related death and usually arises from colorectal polyps. Screening and removal of polyps reduce mortality from CRC. Colorectal polyps are known to aggregate in families; however the genetic determinants for risk of polyps are unknown. In addition, it has been shown that nonsteroidal anti-inflammatory drug (NSAID) use decreases the risk of CRC and the incidence and size of polyps. In this study, we used data from the Tennessee Colorectal Polyp Study and the Tennessee-Indiana Adenoma Recurrence Study to evaluate selected genes from the prostaglandin (PG) metabolism and signaling pathways for association with risk of polyps and for interactions with NSAIDs. Our design consisted of discovery and replication phases for a total of 2,551 Caucasian polyp cases and 3,285 Caucasian controls. We carried out multivariable logistic regression to test for association in both the discovery and replication phase and further examined the results with meta-analysis. We detected association signals in the genes PGE receptor 3 (PTGER3) and 15-hydroxyprostaglandin dehydrogenase (HPGD), both strong biologic candidates for influence on polyp risk. We did not observe the previously reported effects and effect modification in PG-endoperoxide synthase 2 (PTGS2), PGE receptor 2 (PTGER2), or PGE receptor 4 (PTGER4), although we did observe a single nucleotide polymorphism in PTGER2 associated with risk of multiple adenomas. We also observed effect modification of the HPGD signal by NSAID exposure. ©2012 AACR.

  15. [Intestinal polyp of the umbilical cord].

    PubMed

    Guschmann, M; Janda, J; Wenzelides, K; Vogel, M

    2002-02-01

    The morphology, pathogenesis, complications and differential diagnosis of an intestinal polyp of the umbilical cord are presented. The polyp were detected postnatal on the umbilical cord in an healthy male newborn. The presents of intestinal tissue upon the umbilical cord ist possible about the persistence from remnants of the ductus omphalomesentericus with prolapse and differentiation of the intestinal cells. The ductus omphalomesentericus is a tubular structure, a communication between the developing embryonic gut and the yolk sac, forming during the early embryonic life. Obliteration of the omphalomesenteric duct is usually complete by the 10(th) week of gestation. Various portions of the duct may persist, however, giving rise to polyps, fistulas or cysts of the umbilical cord with potentially dangerous clinical consequences. Other tumors of the umbilical cord are myxoma, angioma and teratoma are differential diagnosis.

  16. Variation in diagnostic performance among radiologists at screening CT colonography.

    PubMed

    Pooler, B Dustin; Kim, David H; Hassan, Cesare; Rinaldi, Antonio; Burnside, Elizabeth S; Pickhardt, Perry J

    2013-07-01

    To assess the variation in diagnostic performance among radiologists at screening computed tomographic (CT) colonography. In this HIPAA-compliant, institutional review board-approved study, 6866 asymptomatic adults underwent first-time CT colonographic screening at a single center between January 2005 and November 2011. Results of examinations were interpreted by one of eight board-certified abdominal radiologists (mean number of CT colonographic studies per reader, 858; range, 131-2202). Findings at CT colonography and subsequent colonoscopy were recorded, and key measures of diagnostic performance, including adenoma and advanced neoplasia detection rate, were compared among the radiologists. The overall prevalence of histopathologically confirmed advanced neoplasia was 3.6% and did not differ significantly among radiologists (range, 2.4%-4.4%; P = .067; P = .395 when one outlier was excluded). Overall, 19.5% of polyps detected at CT colonography proved to be advanced neoplasia and did not differ significantly among radiologists (range, 14.4%-23.2%; P = .223). The overall per-polyp endoscopic confirmation rate was 93.5%, ranging from 80.0% to 97.6% among radiologists (P = .585). The overall percentage of nondiagnostic CT colonographic examinations was 0.7% and was consistent among radiologists (range, 0.3%-1.1%; P = .509). Consistent performance for adenoma and advanced neoplasia detection, as well as other clinically relevant end points, were observed among radiologists at CT colonographic screening.

  17. Adaptive statistical iterative reconstruction and Veo: assessment of image quality and diagnostic performance in CT colonography at various radiation doses.

    PubMed

    Yoon, Min A; Kim, Se Hyung; Lee, Jeong Min; Woo, Hyoun Sik; Lee, Eun Sun; Ahn, Se Jin; Han, Joon Koo

    2012-01-01

    To evaluate the diagnostic performance of computed tomography (CT) colonography (CTC) reconstructed with different levels of adaptive statistical iterative reconstruction (ASiR, GE Healthcare) and Veo (model-based iterative reconstruction, GE Healthcare) at various tube currents in detection of polyps in porcine colon phantoms. Five porcine colon phantoms with 46 simulated polyps were scanned at different radiation doses (10, 30, and 50 mA s) and were reconstructed using filtered back projection (FBP), ASiR (20%, 40%, and 60%) and Veo. Eleven data sets for each phantom (10-mA s FBP, 10-mA s 20% ASiR, 10-mA s 40% ASiR, 10-mA s 60% ASiR, 10-mA s Veo, 30-mA s FBP, 30-mA s 20% ASiR, 30-mA s 40% ASiR, 30-mA s 60% ASiR, 30-mA s Veo, and 50-mA s FBP) yielded a total of 55 data sets. Polyp detection sensitivity and confidence level of 2 independent observers were evaluated with the McNemar test, the Fisher exact test, and receiver operating characteristic curve analysis. Comparative analyses of overall image quality score, measured image noise, and interpretation time were also performed. Per-polyp detection sensitivities and specificities were highest in 10-mA s Veo, 30-mA s FBP, 30-mA s 60% ASiR, and 50-mA s FBP (sensitivity, 100%; specificity, 100%). The area-under-the-curve values for the overall performance of each data set was also highest (1.000) at 50-mA s FBP, 30-mA s FBP, 30-mA s 60% ASiR, and 10-mA s Veo. Images reconstructed with ASiR showed statistically significant improvement in per-polyp detection sensitivity as the percent level of per-polyp sensitivity increased (10-mA s FBP vs 10-mA s 20% ASiR, P = 0.011; 10-mA s FBP vs 10-mA s 40% ASiR, P = 0.000; 10-mA s FBP vs 10-mA s 60% ASiR, P = 0.000; 10-mA s 20% ASiR vs 40% ASiR, P = 0.034). Overall image quality score was highest at 30-mA s Veo and 50-mA s FBP. The quantitative measurement of the image noise was lowest at 30-mA s Veo and second lowest at 10-mA s Veo. There was a trend of decrease in time required for image interpretation as the percent level of ASiR increased, and ASiR or Veo was used instead of FBP. However, differences from comparative analyses of overall image quality score, measured image noise, and interpretation time did not reach statistical significance. ASiR and Veo showed improved diagnostic performance with excellent sensitivity and specificity with less image noise and good image quality compared with FBP reconstruction of same radiation dose. Our study confirmed feasibility of low-dose CTC with iterative reconstruction as a promising screening tool with excellent diagnostic performance similar to that of the standard-dose CTC with FBP.

  18. Evaluation of computer-aided detection and diagnosis systems.

    PubMed

    Petrick, Nicholas; Sahiner, Berkman; Armato, Samuel G; Bert, Alberto; Correale, Loredana; Delsanto, Silvia; Freedman, Matthew T; Fryd, David; Gur, David; Hadjiiski, Lubomir; Huo, Zhimin; Jiang, Yulei; Morra, Lia; Paquerault, Sophie; Raykar, Vikas; Samuelson, Frank; Summers, Ronald M; Tourassi, Georgia; Yoshida, Hiroyuki; Zheng, Bin; Zhou, Chuan; Chan, Heang-Ping

    2013-08-01

    Computer-aided detection and diagnosis (CAD) systems are increasingly being used as an aid by clinicians for detection and interpretation of diseases. Computer-aided detection systems mark regions of an image that may reveal specific abnormalities and are used to alert clinicians to these regions during image interpretation. Computer-aided diagnosis systems provide an assessment of a disease using image-based information alone or in combination with other relevant diagnostic data and are used by clinicians as a decision support in developing their diagnoses. While CAD systems are commercially available, standardized approaches for evaluating and reporting their performance have not yet been fully formalized in the literature or in a standardization effort. This deficiency has led to difficulty in the comparison of CAD devices and in understanding how the reported performance might translate into clinical practice. To address these important issues, the American Association of Physicists in Medicine (AAPM) formed the Computer Aided Detection in Diagnostic Imaging Subcommittee (CADSC), in part, to develop recommendations on approaches for assessing CAD system performance. The purpose of this paper is to convey the opinions of the AAPM CADSC members and to stimulate the development of consensus approaches and "best practices" for evaluating CAD systems. Both the assessment of a standalone CAD system and the evaluation of the impact of CAD on end-users are discussed. It is hoped that awareness of these important evaluation elements and the CADSC recommendations will lead to further development of structured guidelines for CAD performance assessment. Proper assessment of CAD system performance is expected to increase the understanding of a CAD system's effectiveness and limitations, which is expected to stimulate further research and development efforts on CAD technologies, reduce problems due to improper use, and eventually improve the utility and efficacy of CAD in clinical practice.

  19. Evaluation of computer-aided detection and diagnosis systemsa)

    PubMed Central

    Petrick, Nicholas; Sahiner, Berkman; Armato, Samuel G.; Bert, Alberto; Correale, Loredana; Delsanto, Silvia; Freedman, Matthew T.; Fryd, David; Gur, David; Hadjiiski, Lubomir; Huo, Zhimin; Jiang, Yulei; Morra, Lia; Paquerault, Sophie; Raykar, Vikas; Samuelson, Frank; Summers, Ronald M.; Tourassi, Georgia; Yoshida, Hiroyuki; Zheng, Bin; Zhou, Chuan; Chan, Heang-Ping

    2013-01-01

    Computer-aided detection and diagnosis (CAD) systems are increasingly being used as an aid by clinicians for detection and interpretation of diseases. Computer-aided detection systems mark regions of an image that may reveal specific abnormalities and are used to alert clinicians to these regions during image interpretation. Computer-aided diagnosis systems provide an assessment of a disease using image-based information alone or in combination with other relevant diagnostic data and are used by clinicians as a decision support in developing their diagnoses. While CAD systems are commercially available, standardized approaches for evaluating and reporting their performance have not yet been fully formalized in the literature or in a standardization effort. This deficiency has led to difficulty in the comparison of CAD devices and in understanding how the reported performance might translate into clinical practice. To address these important issues, the American Association of Physicists in Medicine (AAPM) formed the Computer Aided Detection in Diagnostic Imaging Subcommittee (CADSC), in part, to develop recommendations on approaches for assessing CAD system performance. The purpose of this paper is to convey the opinions of the AAPM CADSC members and to stimulate the development of consensus approaches and “best practices” for evaluating CAD systems. Both the assessment of a standalone CAD system and the evaluation of the impact of CAD on end-users are discussed. It is hoped that awareness of these important evaluation elements and the CADSC recommendations will lead to further development of structured guidelines for CAD performance assessment. Proper assessment of CAD system performance is expected to increase the understanding of a CAD system's effectiveness and limitations, which is expected to stimulate further research and development efforts on CAD technologies, reduce problems due to improper use, and eventually improve the utility and efficacy of CAD in clinical practice. PMID:23927365

  20. The TLR3/TICAM-1 signal constitutively controls spontaneous polyposis through suppression of c-Myc in Apc Min/+ mice.

    PubMed

    Ono, Junya; Shime, Hiroaki; Takaki, Hiromi; Takashima, Ken; Funami, Kenji; Yoshida, Sumito; Takeda, Yohei; Matsumoto, Misako; Kasahara, Masanori; Seya, Tsukasa

    2017-10-17

    Intestinal tumorigenesis is promoted by myeloid differentiation primary response gene 88 (MyD88) activation in response to the components of microbiota in Apc Min/+ mice. Microbiota also contains double-stranded RNA (dsRNA), a ligand for TLR3, which activates the toll-like receptor adaptor molecule 1 (TICAM-1, also known as TRIF) pathway. We established Apc Min/+ Ticam1 -/- mice and their survival was compared to survival of Apc Min/+ Myd88 -/- and wild-type (WT) mice. The properties of polyps were investigated using immunofluorescence staining and RT-PCR analysis. We demonstrate that TICAM-1 is essential for suppression of polyp formation in Apc Min/+ mice. TICAM-1 knockout resulted in shorter survival of mice compared to WT mice or mice with knockout of MyD88 in the Apc Min/+ background. Polyps were more frequently formed in the distal intestine of Apc Min/+ Ticam1 -/- mice than in Apc Min/+ mice. Infiltration of immune cells such as CD11b + and CD8α + cells into the polyps was detected histologically. CD11b and CD8α mRNAs were increased in polyps of Apc Min/+ Ticam1 -/- mice compared to Apc Min/+ mice. Gene expression of inducible nitric oxide synthase (iNOS), interferon (IFN)-γ, CXCL9 and IL-12p40 was increased in polyps of Apc Min/+ Ticam1 -/- mice. mRNA and protein expression of c-Myc, a critical transcription factor for inflammation-associated polyposis, were increased in polyps of Apc Min/+ Ticam1 -/- mice. A Lactobacillus strain producing dsRNA was detected in feces of Apc Min/+ mice. These results imply that the TLR3/TICAM-1 pathway inhibits polyposis through suppression of c-Myc expression and supports long survival in Apc Min/+ mice.

  1. Polyp detection rates using magnification with narrow band imaging and white light

    PubMed Central

    Gilani, Nooman; Stipho, Sally; Panetta, James D; Petre, Sorin; Young, Michele A; Ramirez, Francisco C

    2015-01-01

    AIM: To compare the yield of adenomas between narrow band imaging and white light when using high definition/magnification. METHODS: This prospective, non-randomized comparative study was performed at the endoscopy unit of veteran affairs medical center in Phoenix, Arizona. Consecutive patients undergoing first average risk colorectal cancer screening colonoscopy were selected. Two experienced gastroenterologists performed all the procedures that were blinded to each other’s findings. Demographic details were recorded. Data are presented as mean ± SEM. Proportional data were compared using the χ2 test and means were compared using the Student’s t test. Tandem colonoscopy was performed in a sequential and segmental fashion using one of 3 strategies: white light followed by narrow band imaging [Group A: white light (WL) → narrow band imaging (NBI)]; narrow band imaging followed by white light (Group B: NBI → WL) and, white light followed by white light (Group C: WL → WL). Detection rate of missed polyps and adenomas were evaluated in all three groups. RESULTS: Three hundred patients were studied (100 in each Group). Although the total time for the colonoscopy was similar in the 3 groups (23.8 ± 0.7, 22.2 ± 0.5 and 24.1 ± 0.7 min for Groups A, B and C, respectively), it reached statistical significance between Groups B and C (P < 0.05). The cecal intubation time in Groups B and C was longer than for Group A (6.5 ± 0.4 min and 6.5 ± 0.4 min vs 4.9 ± 0.3 min; P < 0.05). The withdrawal time for Groups A and C was longer than Group B (18.9 ± 0.7 min and 17.6 ± 0.6 min vs 15.7 ± 0.4 min; P < 0.05). Overall miss rate for polyps and adenomas detected in three groups during the second look was 18% and 17%, respectively (P = NS). Detection rate for polyps and adenomas after first look with white light was similar irrespective of the light used during the second look (WL → WL: 13.7% for polyps, 12.6% for adenomas; WL → NBI: 14.2% for polyps, 11.3% for adenomas). Miss rate of polyps and adenomas however was significantly higher when NBI was used first (29.3% and 30.3%, respectively; P < 0.05). Most missed adenomas were ≤ 5 mm in size. There was only one advanced neoplasia (defined by size only) missed during the first look. CONCLUSION: Our data suggest that the tandem nature of the procedure rather than the optical techniques was associated with the detection of additional polyps’ and adenomas. PMID:25992195

  2. Accumulation of CD69+ tissue‑resident memory T cells in the nasal polyps of patients with chronic rhinosinusitis.

    PubMed

    Ickrath, Pascal; Kleinsasser, Norbert; Ding, Xin; Ginzkey, Christian; Beyersdorf, Niklas; Hagen, Rudolf; Kerkau, Thomas; Hackenberg, Stephan

    2018-08-01

    In patients with chronic rhinosinusitis with nasal polyps (CRSwNP), a relative accumulation of cluster of differentiation (CD)8+ T cells over CD4+ T cells occurs in nasal polyps compared with the peripheral blood. Nasal CD8+ T cells and CD4+ T cells predominantly present an effector memory phenotype. Immunological studies have reported that memory T cells recirculate from the tissues to the peripheral blood and a high percentage of these T cells persist within the tissue. The aim of the present study was to characterize CD69+ sphingosine‑1‑phosphate receptor 1 (S1PR1)‑ tissue resident memory T cells (Trm) in the polyps of patients with CRSwNP. Tissue and blood samples were collected from 10 patients undergoing nasal sinus surgery. Expression of specific extra‑ and intracellular molecules were analyzed using multicolor flow cytometry. A significantly higher level of CD8+ T cells than CD4+ T cells was present in nasal polyps, while significantly more CD4+ T cells than CD8+ T cells were detected in the peripheral blood of patients with CRSwNP. The frequency of CD69+ T cells was significantly higher in CD8+ and CD4+ T cells in nasal polyps compared with the peripheral blood. The frequency of CD69+ S1PR1‑ Trm was also significantly higher in CD4+ and CD8+ T cells from nasal polyps compared with the peripheral blood. Within polyps, the frequency of CD69+ S1PR1‑ Trm was again significantly higher in CD8+ compared with CD4+ T cells. In summary, a significantly higher frequency of CD69+ S1PR1‑ T cells was observed in the nasal polyps compared with the peripheral blood in patients with CRSwNP. The results of the present study suggest that local regulation of the immune response occurs within nasal polyps. As such, Trm should be considered a potential stimulus in the pathogenesis of nasal polyps. However, the role of Trm in nasal polyps as a pathogenic trigger of the local inflammatory reaction requires further investigation.

  3. Preoperative care of Polypoid exposed mucosal template in bladder exstrophy: the role of high-barrier plastic wraps in reducing inflammation and polyp size.

    PubMed

    Sabetkish, Nastaran; Sabetkish, Shabnam; Kajbafzadeh, Abdol-Mohammad

    2018-01-26

    To assess the role of high-barrier plastic wrap in reducing the number and size of polyps, as well as decreasing the inflammation and allergic reactions in exstrophy cases, and to compare the results with the application of low-barrier wrap. Eight patients with bladder exstrophy-epispadias complex (BEEC) that had used a low density polyethylene (LDPE) wrap for coverage of the exposed polypoid bladder in preoperative care management were referred. The main complaint of their parents was increase in size and number of polyps. After a period of 2 months using the same wrap and observing the increasing pattern in size of polyps, these patients were recommended to use a high-barrier wrap which is made of polyvinylidene chloride (PVdC), until closure. Patients were monitored for the number and size of polyps before and after the change of barriers. The incidence of para-exstrophy skin infection/inflammation and skin allergy were assessed. Biopsies were taken from the polyps to identify histopathological characteristics of the exposed polyps. The high barrier wrap was applied for a mean ± SD duration of 12±2.1 months. Polyps' size and number decreased after 12 months. No allergic reaction was detected in patients after the usage of PVdC; three patients suffered from low-grade skin allergy when LDPE was applied. Also, pre-malignant changes were observed in none of the patients in histopathological examination after the application of PVdC. Polyps' size and number and skin allergy may significantly decrease with the use of a high-barrier wrap. Certain PVdC wraps with more integrity and less evaporative permeability may be more "exstrophy-friendly". Copyright® by the International Brazilian Journal of Urology.

  4. Dynamic Tumor Growth Patterns in a Novel Murine Model of Colorectal Cancer

    PubMed Central

    Olson, Terrah J. Paul; Hadac, Jamie N.; Sievers, Chelsie K.; Leystra, Alyssa A.; Deming, Dustin A.; Zahm, Christopher D.; Albrecht, Dawn M.; Nomura, Alice; Nettekoven, Laura A.; Plesh, Lauren K.; Clipson, Linda; Sullivan, Ruth; Newton, Michael A.; Schelman, William R.; Halberg, Richard B.

    2014-01-01

    Colorectal cancer (CRC) often arises from adenomatous colonic polyps. Polyps can grow and progress to cancer, but may also remain static in size, regress, or resolve. Predicting which progress and which remain benign is difficult. We developed a novel long-lived murine model of CRC with tumors that can be followed by colonoscopy. Our aim was to assess whether these tumors have similar growth patterns and histologic fates to human colorectal polyps to identify features to aid in risk-stratification of colonic tumors. Long-lived ApcMin/+ mice were treated with dextran sodium sulfate to promote colonic tumorigenesis. Tumor growth patterns were characterized by serial colonoscopy with biopsies obtained for immunohistochemistry and gene expression profiling. Tumors grew, remained static, regressed, or resolved over time with different relative frequencies. Newly developed tumors demonstrated higher rates of growth and resolution than more established tumors that tended to remain static in size. Colonic tumors were hyperplastic lesions (3%), adenomas (73%), intramucosal carcinomas (20%), or adenocarcinomas (3%). Interestingly, the level of β-catenin was higher in adenomas that became intratumoral carcinomas as compared to those that failed to progress. In addition, differentially expressed genes between adenomas and intramucosal carcinomas were identified. This novel murine model of intestinal tumorigenesis develops colonic tumors that can be monitored by serial colonoscopy, mirror growth patterns seen in human colorectal polyps, and progress to CRC. Further characterization of cellular and molecular features are needed to determine which features can be used to risk-stratify polyps for progression to CRC and potentially guide prevention strategies. PMID:24196829

  5. Computed tomographic colonography to screen for colorectal cancer, extracolonic cancer, and aortic aneurysm: model simulation with cost-effectiveness analysis.

    PubMed

    Hassan, Cesare; Pickhardt, Perry J; Pickhardt, Perry; Laghi, Andrea; Kim, Daniel H; Kim, Daniel; Zullo, Angelo; Iafrate, Franco; Di Giulio, Lorenzo; Morini, Sergio

    2008-04-14

    In addition to detecting colorectal neoplasia, abdominal computed tomography (CT) with colonography technique (CTC) can also detect unsuspected extracolonic cancers and abdominal aortic aneurysms (AAA).The efficacy and cost-effectiveness of this combined abdominal CT screening strategy are unknown. A computerized Markov model was constructed to simulate the occurrence of colorectal neoplasia, extracolonic malignant neoplasm, and AAA in a hypothetical cohort of 100,000 subjects from the United States who were 50 years of age. Simulated screening with CTC, using a 6-mm polyp size threshold for reporting, was compared with a competing model of optical colonoscopy (OC), both without and with abdominal ultrasonography for AAA detection (OC-US strategy). In the simulated population, CTC was the dominant screening strategy, gaining an additional 1458 and 462 life-years compared with the OC and OC-US strategies and being less costly, with a savings of $266 and $449 per person, respectively. The additional gains for CTC were largely due to a decrease in AAA-related deaths, whereas the modeled benefit from extracolonic cancer downstaging was a relatively minor factor. At sensitivity analysis, OC-US became more cost-effective only when the CTC sensitivity for large polyps dropped to 61% or when broad variations of costs were simulated, such as an increase in CTC cost from $814 to $1300 or a decrease in OC cost from $1100 to $500. With the OC-US approach, suboptimal compliance had a strong negative influence on efficacy and cost-effectiveness. The estimated mortality from CT-induced cancer was less than estimated colonoscopy-related mortality (8 vs 22 deaths), both of which were minor compared with the positive benefit from screening. When detection of extracolonic findings such as AAA and extracolonic cancer are considered in addition to colorectal neoplasia in our model simulation, CT colonography is a dominant screening strategy (ie, more clinically effective and more cost-effective) over both colonoscopy and colonoscopy with 1-time ultrasonography.

  6. Low plasma selenium concentration is associated with elevated risk to neoplastic polyps of the colon

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clark, L.C.; Hixson, L.G.; Sampliner, R.E.

    1991-03-11

    A cross-sectional study was conducted to examine the relationship of selenium (Se) status and polyps incidence in a sequential series of 100 patients undergoing outpatient colonoscopies at the Tucson VA Hospital. Se was measured in plasma samples by electrothermal atomic absorption spectrophotometry with Zeeman background correction using a reduced palladium matrix modified. The activities of the Se-dependent enzyme glutathione peroxidase (SeGSHpx) were measured using H{sub 2}O{sub 2} as substrate in all plasma samples and in colonic mucosal biopsies obtained from some patients. The mean plasma Se concentration of patients without polyps was 134 ng/ml. Mean plasma Se levels of patientsmore » with only diminutive or large polyps were 127 ng/ml and 125 ng/ml; while patients with polyps of both sizes had a mean plasma Se level of 121 ng/ml. Patients with no reported history of cancer, neoplastic polyps or prior colonoscopy, showed an inverse association of plasma Se level and risk of benign colonic neoplasms. The age-adjusted odds ratio for neoplastic polyps was 3.8 for patients with plasma Se levels below vs. above the median value. This association was stronger for patients under 68 yrs of age than for older patients. Activities of SeGSHpx in plasma or colonic mucosa were not related to plasma Se level; however, smokers showed greater SeGSHpx activities than non-smokers. This study is the first to detect an association of Se status and risk to neoplastic polyps of the colon.« less

  7. The serrated neoplasia pathway of colorectal tumors: Identification of MUC5AC hypomethylation as an early marker of polyps with malignant potential.

    PubMed

    Renaud, Florence; Mariette, Christophe; Vincent, Audrey; Wacrenier, Agnès; Maunoury, Vincent; Leclerc, Julie; Coppin, Lucie; Crépin, Michel; Van Seuningen, Isabelle; Leteurtre, Emmanuelle; Buisine, Marie-Pierre

    2016-03-15

    The serrated neoplasia pathway accounts for 20-30% of colorectal cancers (CRC), which are characterized by extensive methylation (CpG island methylation phenotype, CIMP), frequent BRAF mutation and high microsatellite instability (MSI). We recently identified MUC5AC mucin gene hypomethylation as a specific marker of MSI CRC. The early identification of preneoplastic lesions among serrated polyps is currently challenging. Here, we performed a detailed pathological and molecular analysis of a large series of colorectal serrated polyps and evaluated the usefulness of mucin genes MUC2 and MUC5AC to differentiate serrated polyps and to identify lesions with malignant potential. A series of 330 colorectal polyps including 218 serrated polyps [42 goblet cell-rich hyperplastic polyps (GCHP), 68 microvesicular hyperplastic polyps (MVHP), 100 sessile serrated adenoma (SSA) and eight traditional serrated adenoma (TSA)] and 112 conventional adenomas was analyzed for BRAF/KRAS mutations, MSI, CIMP, MLH1 and MGMT methylation, and MUC2 and MUC5AC expression and methylation. We show that MUC5AC hypomethylation is an early event in the serrated neoplasia pathway, and specifically detects MVHP and SSA, arguing for a filiation between MVHP, SSA and CIMP-H/MSI CRC, whereas GCHP and TSA arise from a distinct pathway. Moreover, MUC5AC hypomethylation specifically identified serrated lesions with BRAF mutation, CIMP-H or MSI, suggesting that it may be useful to identify serrated neoplasia pathway-related precursor lesions. Our data suggest that MVHP should be recognized among HP and require particular attention. © 2015 UICC.

  8. Computer-aided detection and quantification of endolymphatic hydrops within the mouse cochlea in vivo using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Liu, George S.; Kim, Jinkyung; Applegate, Brian E.; Oghalai, John S.

    2017-07-01

    Diseases that cause hearing loss and/or vertigo in humans such as Meniere's disease are often studied using animal models. The volume of endolymph within the inner ear varies with these diseases. Here, we used a mouse model of increased endolymph volume, endolymphatic hydrops, to develop a computer-aided objective approach to measure endolymph volume from images collected in vivo using optical coherence tomography. The displacement of Reissner's membrane from its normal position was measured in cochlear cross sections. We validated our computer-aided measurements with manual measurements and with trained observer labels. This approach allows for computer-aided detection of endolymphatic hydrops in mice, with test performance showing sensitivity of 91% and specificity of 87% using a running average of five measurements. These findings indicate that this approach is accurate and reliable for classifying endolymphatic hydrops and quantifying endolymph volume.

  9. Development of a Computer-Aided Diagnosis System for Early Detection of Masses Using Retrospectively Detected Cancers on Prior Mammograms

    DTIC Science & Technology

    2006-06-01

    Hadjiiski, and N. Petrick, "Computerized nipple identification for multiple image analysis in computer-aided diagnosis," Medical Physics 31, 2871...candidates, 3 identification of suspicious objects, 4 feature extraction and analysis, and 5 FP reduc- tion by classification of normal tissue...detection of microcalcifi- cations on digitized mammograms.41 An illustration of a La- placian decomposition tree is shown on the left-hand side of Fig. 4

  10. Polyp measurement with CT colonography: multiple-reader, multiple-workstation comparison.

    PubMed

    Young, Brett M; Fletcher, J G; Paulsen, Scott R; Booya, Fargol; Johnson, C Daniel; Johnson, Kristina T; Melton, Zackary; Rodysill, Drew; Mandrekar, Jay

    2007-01-01

    The risk of invasive colorectal cancer in colorectal polyps correlates with lesion size. Our purpose was to define the most accurate methods for measuring polyp size at CT colonography (CTC) using three models of workstations and multiple observers. Six reviewers measured 24 unique polyps of known size (5, 7, 10, and 12 mm), shape (sessile, flat, and pedunculated), and location (straight or curved bowel segment) using CTC data sets obtained at two doses (5 mAs and 65 mAs) and a previously described colonic phantom model. Reviewers measured the largest diameter of polyps on three proprietary workstations. Each polyp was measured with lung and soft-tissue windows on axial, 2D multiplanar reconstruction (MPR), and 3D images. There were significant differences among measurements obtained at various settings within each workstation (p < 0.0001). Measurements on 2D images were more accurate with lung window than with soft-tissue window settings (p < 0.0001). For the 65-mAs data set, the most accurate measurements were obtained in analysis of axial images with lung window, 2D MPR images with lung window, and 3D tissue cube images for Wizard, Advantage, and Vitrea workstations, respectively, without significant differences in accuracy among techniques (0.11 < p < 0.59). The mean absolute error values for these optimal settings were 0.48 mm, 0.61 mm, and 0.76 mm, respectively, for the three workstations. Within the ultralow-dose 5-mAs data set the best methods for Wizard, Advantage, and Vitrea were axial with lung window, 2D MPR with lung window, and 2D MPR with lung window, respectively. Use of nearly all measurement methods, except for the Vitrea 3D tissue cube and the Wizard 2D MPR with lung window, resulted in undermeasurement of the true size of the polyps. Use of CTC computer workstations facilitates accurate polyp measurement. For routine CTC examinations, polyps should be measured with lung window settings on 2D axial or MPR images (Wizard and Advantage) or 3D images (Vitrea). When these optimal methods are used, these three commercial workstations do not differ significantly in acquisition of accurate polyp measurements at routine dose settings.

  11. Proteins with CHADs (Conserved Histidine α-Helical Domains) Are Attached to Polyphosphate Granules In Vivo and Constitute a Novel Family of Polyphosphate-Associated Proteins (Phosins).

    PubMed

    Tumlirsch, Tony; Jendrossek, Dieter

    2017-04-01

    On the basis of bioinformatic evidence, we suspected that proteins with a CYTH ( Cy aB th iamine triphosphatase) domain and/or a CHAD ( c onserved h istidine α -helical d omain) motif might represent polyphosphate (polyP) granule-associated proteins. We found no evidence of polyP targeting by proteins with CYTH domains. In contrast, two CHAD motif-containing proteins from Ralstonia eutropha H16 (A0104 and B1017) that were expressed as fusions with enhanced yellow fluorescent protein (eYFP) colocalized with polyP granules. While the expression of B1017 was not detectable, the A0104 protein was specifically identified in an isolated polyP granule fraction by proteome analysis. Moreover, eYFP fusions with the CHAD motif-containing proteins MGMSRV2-1987 from Magnetospirillum gryphiswaldense and PP2307 from Pseudomonas putida also colocalized with polyP granules in a transspecies-specific manner. These data indicated that CHAD-containing proteins are generally attached to polyP granules. Together with the findings from four previously polyP-attached proteins (polyP kinases), the results of this study raised the number of polyP-associated proteins in R. eutropha to six. We suggest designating polyP granule-bound proteins with CHAD motifs as phosins ( pho sphate), analogous to pha sins and oleo sins that are specifically bound to the surface of polyhydroxyalkanoate (PHA) granules in PHA-accumulating bacteria and to oil droplets in oil seed plants, respectively. IMPORTANCE The importance of polyphosphate (polyP) for life is evident from the ubiquitous presence of polyP in all species on earth. In unicellular eukaryotic microorganisms, polyP is located in specific membrane-enclosed organelles, called acidocalcisomes. However, in most prokaryotes, polyP is present as insoluble granules that have been designated previously as volutin granules. Almost nothing is known regarding the macromolecular composition of polyP granules. Particularly, the absence or presence of cellular compounds on the surface of polyP granules has not yet been investigated. In this study, we identified a novel class of proteins that are attached to the surface of polyP granules in three model species of Alphaproteobacteria , Betaproteobacteria , and Gammaproteobacteria These proteins are characterized by the presence of a CHAD ( c onserved h istidine α -helical d omain) motif that functions as a polyP granule-targeting signal. We suggest designating CHAD motif-containing proteins as phosins [analogous to phasins for poly(3-hydroxybutyrate)-associated proteins and to oleosins for oil droplet-associated proteins in oil seed plants]. The expression of phosins in different species confirmed their polyP-targeting function in a transspecies-specific manner. We postulate that polyP granules in prokaryotic species generally have a complex surface structure that consists of one to several polyP kinases and phosin proteins. We suggest differentiating polyP granules from acidocalcisomes by designating them as polyphosphatosomes. Copyright © 2017 American Society for Microbiology.

  12. A standardized imaging protocol for the endoscopic prediction of dysplasia within sessile serrated polyps (with video).

    PubMed

    Tate, David J; Jayanna, Mahesh; Awadie, Halim; Desomer, Lobke; Lee, Ralph; Heitman, Steven J; Sidhu, Mayenaaz; Goodrick, Kathleen; Burgess, Nicholas G; Mahajan, Hema; McLeod, Duncan; Bourke, Michael J

    2018-01-01

    Dysplasia within sessile serrated polyps (SSPs) is difficult to detect and may be mistaken for an adenoma, risking incomplete resection of the background serrated tissue, and is strongly implicated in interval cancer after colonoscopy. The use of endoscopic imaging to detect dysplasia within SSPs has not been systematically studied. Consecutively detected SSPs ≥8 mm in size were evaluated by using a standardized imaging protocol at a tertiary-care endoscopy center over 3 years. Lesions suspected as SSPs were analyzed with high-definition white light then narrow-band imaging. A demarcated area with a neoplastic pit pattern (Kudo type III/IV, NICE type II) was sought among the serrated tissue. If this was detected, the lesion was labeled dysplastic (sessile serrated polyp with dysplasia); if not, it was labeled non-dysplastic (sessile serrated polyp without dysplasia). Histopathology was reviewed by 2 blinded specialist GI pathologists. A total of 141 SSPs were assessed in 83 patients. Median lesion size was 15.0 mm (interquartile range 10-20), and 54.6% were in the right side of the colon. Endoscopic evidence of dysplasia was detected in 36 of 141 (25.5%) SSPs; of these, 5 of 36 (13.9%) lacked dysplasia at histopathology. Two of 105 (1.9%) endoscopically designated non-dysplastic SSPs had dysplasia at histopathology. Endoscopic imaging, therefore, had an accuracy of 95.0% (95% confidence interval [CI], 90.1%-97.6%) and a negative predictive value of 98.1% (95% CI, 92.6%-99.7%) for detection of dysplasia within SSPs. Dysplasia within SSPs can be detected accurately by using a simple, broadly applicable endoscopic imaging protocol that allows complete resection. Independent validation of this protocol and its dissemination to the wider endoscopic community may have a significant impact on rates of interval cancer. (Clinical trial registration number: NCT03100552.). Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  13. An improved high order texture features extraction method with application to pathological diagnosis of colon lesions for CT colonography

    NASA Astrophysics Data System (ADS)

    Song, Bowen; Zhang, Guopeng; Lu, Hongbing; Wang, Huafeng; Han, Fangfang; Zhu, Wei; Liang, Zhengrong

    2014-03-01

    Differentiation of colon lesions according to underlying pathology, e.g., neoplastic and non-neoplastic, is of fundamental importance for patient management. Image intensity based textural features have been recognized as a useful biomarker for the differentiation task. In this paper, we introduce high order texture features, beyond the intensity, such as gradient and curvature, for that task. Based on the Haralick texture analysis method, we introduce a virtual pathological method to explore the utility of texture features from high order differentiations, i.e., gradient and curvature, of the image intensity distribution. The texture features were validated on database consisting of 148 colon lesions, of which 35 are non-neoplastic lesions, using the random forest classifier and the merit of area under the curve (AUC) of the receiver operating characteristics. The results show that after applying the high order features, the AUC was improved from 0.8069 to 0.8544 in differentiating non-neoplastic lesion from neoplastic ones, e.g., hyperplastic polyps from tubular adenomas, tubulovillous adenomas and adenocarcinomas. The experimental results demonstrated that texture features from the higher order images can significantly improve the classification accuracy in pathological differentiation of colorectal lesions. The gain in differentiation capability shall increase the potential of computed tomography (CT) colonography for colorectal cancer screening by not only detecting polyps but also classifying them from optimal polyp management for the best outcome in personalized medicine.

  14. Tandem alternative polyadenylation events of genes in non-eosinophilic nasal polyp tissue identified by high-throughput sequencing analysis

    PubMed Central

    TIAN, PENG; LI, JIE; LIU, XIANG; LI, YUXI; CHEN, MEIHENG; MA, YUN; ZHENG, YI QING; FU, YONGGUI; ZOU, HUA

    2014-01-01

    Nasal polyps (NP) is highly associated with the disorder of immune cells. Alternative polyadenylation (APA) produces mRNA isoforms with different length of 3′-untranslated region (UTR) and regulates gene expression. It has been proven that this APA-mediated regulation of 3′UTR length is an immune-associated phenomenon. The aim of this study was to investigate the genome-wide alternative tandem 3′UTR length switching events in non-eosinophilic nasal polyp tissue. Thirteen patients diagnosed as having non-eosinophilic nasal polyps were included in this study. Nasal polyp tissue and control mucosa were collected during surgery. The 3′ end library of cDNA was constructed. The recovered libraries were sequenced with second sequencing technology, and the sequencing data were analyzed by an in-house bioinformatics pipeline. Tandem 3′UTR length switching between samples was detected by a test of linear trend alternative to independence. We found a significant alteration in the tandem 3′UTR length in 1,920 genes in nasal polyp samples. Functional annotation results showed that several gene ontology (GO) terms were enriched in the list of genes with switched APA sites, including regulation of transcription, macromolecule catabolic localization and mRNA processing. The results suggested that APA-mediated alternative 3′UTR regulation plays an important role in the post-transcriptional regulation of gene expression in non-eosinophilic nasal polyps. PMID:24715051

  15. Computer-aided diagnostic detection system of venous beading in retinal images

    NASA Astrophysics Data System (ADS)

    Yang, Ching-Wen; Ma, DyeJyun; Chao, ShuennChing; Wang, ChuinMu; Wen, Chia-Hsien; Lo, ChienShun; Chung, Pau-Choo; Chang, Chein-I.

    2000-05-01

    The detection of venous beading in retinal images provides an early sign of diabetic retinopathy and plays an important role as a preprocessing step in diagnosing ocular diseases. We present a computer-aided diagnostic system to automatically detect venous beading of blood vessels. It comprises of two modules, referred to as the blood vessel extraction module and the venus beading detection module. The former uses a bell-shaped Gaussian kernel with 12 azimuths to extract blood vessels while the latter applies a neural network-based shape cognitron to detect venous beading among the extracted blood vessels for diagnosis. Both modules are fully computer-automated. To evaluate the proposed system, 61 retinal images (32 beaded and 29 normal images) are used for performance evaluation.

  16. Variation in Diagnostic Performance among Radiologists at Screening CT Colonography

    PubMed Central

    Pooler, B. Dustin; Kim, David H.; Hassan, Cesare; Rinaldi, Antonio; Burnside, Elizabeth S.

    2013-01-01

    Purpose: To assess the variation in diagnostic performance among radiologists at screening computed tomographic (CT) colonography. Materials and Methods: In this HIPAA-compliant, institutional review board–approved study, 6866 asymptomatic adults underwent first-time CT colonographic screening at a single center between January 2005 and November 2011. Results of examinations were interpreted by one of eight board-certified abdominal radiologists (mean number of CT colonographic studies per reader, 858; range, 131–2202). Findings at CT colonography and subsequent colonoscopy were recorded, and key measures of diagnostic performance, including adenoma and advanced neoplasia detection rate, were compared among the radiologists. Results: The overall prevalence of histopathologically confirmed advanced neoplasia was 3.6% and did not differ significantly among radiologists (range, 2.4%–4.4%; P = .067; P = .395 when one outlier was excluded). Overall, 19.5% of polyps detected at CT colonography proved to be advanced neoplasia and did not differ significantly among radiologists (range, 14.4%–23.2%; P = .223). The overall per-polyp endoscopic confirmation rate was 93.5%, ranging from 80.0% to 97.6% among radiologists (P = .585). The overall percentage of nondiagnostic CT colonographic examinations was 0.7% and was consistent among radiologists (range, 0.3%–1.1%; P = .509). Conclusion: Consistent performance for adenoma and advanced neoplasia detection, as well as other clinically relevant end points, were observed among radiologists at CT colonographic screening. © RSNA, 2013 PMID:23449954

  17. Hyperspectral imaging of colonic polyps in vivo (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Clancy, Neil T.; Elson, Daniel S.; Teare, Julian

    2017-02-01

    Standard endoscopic tools restrict clinicians to making subjective visual assessments of lesions detected in the bowel, with classification results depending strongly on experience level and training. Histological examination of resected tissue remains the diagnostic gold standard, meaning that all detected lesions are routinely removed. This subjects the patient to risk of polypectomy-related injury, and places significant workload and economic burdens on the hospital. An objective endoscopic classification method would allow hyperplastic polyps, with no malignant potential, to be left in situ, or low grade adenomas to be resected and discarded without histology. A miniature multimodal flexible endoscope is proposed to obtain hyperspectral reflectance and dual excitation autofluorescence information from polyps in vivo. This is placed inside the working channel of a conventional colonoscope, with the external scanning and detection optics on a bedside trolley. A blue and violet laser diode pair excite endogenous fluorophores in the respiration chain, while the colonoscope's xenon light source provides broadband white light for diffuse reflectance measurements. A push-broom HSI scanner collects the hypercube. System characterisation experiments are presented, defining resolution limits as well as acquisition settings for optimal spectral, spatial and temporal performance. The first in vivo results in human subjects are presented, demonstrating the clinical utility of the device. The optical properties (reflectance and autofluorescence) of imaged polyps are quantified and compared to the histologically-confirmed tissue type as well as the clinician's visual assessment. Further clinical studies will allow construction of a full robust training dataset for development of classification schemes.

  18. Feasibility of Using the Marginal Blood Vessels as Reference Landmarks for CT Colonography

    PubMed Central

    Wei, Zhuoshi; Yao, Jianhua; Wang, Shijun; Liu, Jiamin; Dwyer, Andrew J.; Pickhardt, Perry J.; Nowinski, Wieslaw L.; Summers, Ronald M.

    2015-01-01

    OBJECTIVE The purpose of this study was to show the spatial relationship of the colonic marginal blood vessels and the teniae coli on CT colonography (CTC) and the use of the marginal blood vessels for supine-prone registration of polyps and for determination of proper connectivity of collapsed colonic segments. MATERIALS AND METHODS We manually labeled the marginal blood vessels on 15 CTC examinations. Colon segmentation, centerline extraction, teniae detection, and teniae identification were automatically performed. For assessment of their spatial relationships, the distances from the marginal blood vessels to the three teniae coli and to the colon were measured. Student t tests (paired, two-tailed) were performed to evaluate the differences among these distances. To evaluate the reliability of the marginal vessels as reference points for polyp correlation, we analyzed 20 polyps from 20 additional patients who underwent supine and prone CTC. The average difference of the circumferential polyp position on the supine and prone scans was computed. Student t tests (paired, two-tailed) were performed to evaluate the supine-prone differences of the distance. We performed a study on 10 CTC studies from 10 patients with collapsed colonic segments by manually tracing the marginal blood vessels near the collapsed regions to resolve the ambiguity of the colon path. RESULTS The average distances (± SD) from the marginal blood vessels to the tenia mesocolica, tenia omentalis, and tenia libera were 20.1 ± 3.1 mm (95% CI, 18.5–21.6 mm), 39.5 ± 4.8 mm (37.1–42.0 mm), and 36.9 ± 4.2 mm (34.8–39.1 mm), respectively. Pairwise comparison showed that these distances to the tenia libera and tenia omentalis were significantly different from the distance to the tenia mesocolica (p < 0.001). The average distance from the marginal blood vessels to the colon wall was 15.3 ± 2.0 mm (14.2–16.3 mm). For polyp localization, the average difference of the circumferential polyp position on the supine and prone scans was 9.6 ± 9.4 mm (5.5–13.7 mm) (p = 0.15) and expressed as a percentage of the colon circumference was 3.1% ± 2.0% (2.3–4.0%) (p = 0.83). We were able to trace the marginal blood vessels for 10 collapsed colonic segments and determine the paths of the colon in these regions. CONCLUSION The marginal blood vessels run parallel to the colon in proximity to the tenia mesocolica and enable accurate supine-prone registration of polyps and localization of the colon path in areas of collapse. Thus, the marginal blood vessels may be used as reference landmarks complementary to the colon centerline and teniae coli. PMID:24370165

  19. Dynamic Model for Life History of Scyphozoa

    PubMed Central

    Xie, Congbo; Fan, Meng; Wang, Xin; Chen, Ming

    2015-01-01

    A two-state life history model governed by ODEs is formulated to elucidate the population dynamics of jellyfish and to illuminate the triggering mechanism of its blooms. The polyp-medusa model admits trichotomous global dynamic scenarios: extinction, polyps survival only, and both survival. The population dynamics sensitively depend on several biotic and abiotic limiting factors such as substrate, temperature, and predation. The combination of temperature increase, substrate expansion, and predator diminishment acts synergistically to create a habitat that is more favorable for jellyfishes. Reducing artificial marine constructions, aiding predator populations, and directly controlling the jellyfish population would help to manage the jellyfish blooms. The theoretical analyses and numerical experiments yield several insights into the nature underlying the model and shed some new light on the general control strategy for jellyfish. PMID:26114642

  20. Dynamic Model for Life History of Scyphozoa.

    PubMed

    Xie, Congbo; Fan, Meng; Wang, Xin; Chen, Ming

    2015-01-01

    A two-state life history model governed by ODEs is formulated to elucidate the population dynamics of jellyfish and to illuminate the triggering mechanism of its blooms. The polyp-medusa model admits trichotomous global dynamic scenarios: extinction, polyps survival only, and both survival. The population dynamics sensitively depend on several biotic and abiotic limiting factors such as substrate, temperature, and predation. The combination of temperature increase, substrate expansion, and predator diminishment acts synergistically to create a habitat that is more favorable for jellyfishes. Reducing artificial marine constructions, aiding predator populations, and directly controlling the jellyfish population would help to manage the jellyfish blooms. The theoretical analyses and numerical experiments yield several insights into the nature underlying the model and shed some new light on the general control strategy for jellyfish.

  1. Colon Capsule Endoscopy for the Detection of Colorectal Polyps: An Economic Analysis

    PubMed Central

    Palimaka, Stefan; Blackhouse, Gord; Goeree, Ron

    2015-01-01

    Background Colorectal cancer is a leading cause of mortality and morbidity in Ontario. Most cases of colorectal cancer are preventable through early diagnosis and the removal of precancerous polyps. Colon capsule endoscopy is a non-invasive test for detecting colorectal polyps. Objectives The objectives of this analysis were to evaluate the cost-effectiveness and the impact on the Ontario health budget of implementing colon capsule endoscopy for detecting advanced colorectal polyps among adult patients who have been referred for computed tomographic (CT) colonography. Methods We performed an original cost-effectiveness analysis to assess the additional cost of CT colonography and colon capsule endoscopy resulting from misdiagnoses. We generated diagnostic accuracy data from a clinical evidence-based analysis (reported separately), and we developed a deterministic Markov model to estimate the additional long-term costs and life-years lost due to false-negative results. We then also performed a budget impact analysis using data from Ontario administrative sources. One-year costs were estimated for CT colonography and colon capsule endoscopy (replacing all CT colonography procedures, and replacing only those CT colonography procedures in patients with an incomplete colonoscopy within the previous year). We conducted this analysis from the payer perspective. Results Using the point estimates of diagnostic accuracy from the head-to-head study between colon capsule endoscopy and CT colonography, we found the additional cost of false-positive results for colon capsule endoscopy to be $0.41 per patient, while additional false-negatives for the CT colonography arm generated an added cost of $116 per patient, with 0.0096 life-years lost per patient due to cancer. This results in an additional cost of $26,750 per life-year gained for colon capsule endoscopy compared with CT colonography. The total 1-year cost to replace all CT colonography procedures with colon capsule endoscopy in Ontario is about $2.72 million; replacing only those CT colonography procedures in patients with an incomplete colonoscopy in the previous year would cost about $740,600 in the first year. Limitations The difference in accuracy between colon capsule endoscopy and CT colonography was not statistically significant for the detection of advanced adenomas (≥ 10 mm in diameter), according to the head-to-head clinical study from which the diagnostic accuracy was taken. This leads to uncertainty in the economic analysis, with results highly sensitive to changes in diagnostic accuracy. Conclusions The cost-effectiveness of colon capsule endoscopy for use in patients referred for CT colonography is $26,750 per life-year, assuming an increased sensitivity of colon capsule endoscopy. Replacement of CT colonography with colon capsule endoscopy is associated with moderate costs to the health care system. PMID:26366240

  2. Pediatric colonoscopy in South China: a 12-year experience in a tertiary center.

    PubMed

    Lei, Pingguang; Gu, Fang; Hong, Liru; Sun, Yuli; Li, Minrui; Wang, Huiling; Zhong, Bihui; Chen, Minhu; Cui, Yi; Zhang, Shenghong

    2014-01-01

    To investigate: 1) the demographics and clinical characteristics, 2) the findings, and 3) the safety and effectiveness in a cohort of Chinese pediatric patients undergoing colonoscopy. The study participants were consecutive patients aged ≤14 years old that underwent their first colonoscopy in the endoscopy center at the First Affiliated Hospital, Sun Yat-sen University between Jan. 1, 2001 and Dec. 31, 2012. Demographic, clinical, endoscopic, and pathological findings were collected. The cohort consisted of 322 patients, including 218 boys (67.7%) and 104 girls (32.3%). The median age was 8.0 years old and ranged from 9 months to 14 years old. Hematochezia (48.8%) and abdominal pain/discomfort (41.3%) were the most common presentations preceding pediatric colonoscopy. The caecal intubation success rate was 96.3%. No serious complications occurred during the procedures. A total of 227 patients (70.5%) received a positive diagnosis under endoscopy, including 138 patients with polyps and 53 patients with inflammatory bowel disease (IBD). Among the patients with polyps, 71.0% were juvenile polyps. Comparisons between years 2001-2006 and 2007-2012 showed that the IBD detection rate increased significantly (4.6% vs. 22.4%, P<0.001), while the opposite occurred for the polyp detection rate (73.1% vs. 27.6%, P<0.001). Colonoscopy in pediatric patients is a safe and effective procedure. Polyps are the primary finding during colonoscopy. In South China there has been an increase in pediatric patients diagnosed with IBD over the past decade. However, a large epidemiological study is needed to confirm our findings.

  3. Toward the detection of abnormal chest radiographs the way radiologists do it

    NASA Astrophysics Data System (ADS)

    Alzubaidi, Mohammad; Patel, Ameet; Panchanathan, Sethuraman; Black, John A., Jr.

    2011-03-01

    Computer Aided Detection (CADe) and Computer Aided Diagnosis (CADx) are relatively recent areas of research that attempt to employ feature extraction, pattern recognition, and machine learning algorithms to aid radiologists in detecting and diagnosing abnormalities in medical images. However, these computational methods are based on the assumption that there are distinct classes of abnormalities, and that each class has some distinguishing features that set it apart from other classes. However, abnormalities in chest radiographs tend to be very heterogeneous. The literature suggests that thoracic (chest) radiologists develop their ability to detect abnormalities by developing a sense of what is normal, so that anything that is abnormal attracts their attention. This paper discusses an approach to CADe that is based on a technique called anomaly detection (which aims to detect outliers in data sets) for the purpose of detecting atypical regions in chest radiographs. However, in order to apply anomaly detection to chest radiographs, it is necessary to develop a basis for extracting features from corresponding anatomical locations in different chest radiographs. This paper proposes a method for doing this, and describes how it can be used to support CADe.

  4. Endoscopists can sustain high performance for the optical diagnosis of colorectal polyps following standardized and continued training.

    PubMed

    McGill, Sarah K; Soetikno, Roy; Rastogi, Amit; Rouse, Robert V; Sato, Tohru; Bansal, Ajay; McQuaid, Kenneth; Kaltenbach, Tonya

    2015-03-01

    The learning curve for optical diagnosis of colorectal polyps with the narrow-band imaging (NBI) is unknown. To forego histological analysis of diminutive polyps diagnosed optically with high confidence, guidelines recommend ≥ 90 % negative predictive value (NPV) and concordance of ≥ 90 % for surveillance intervals predicted optically and histologically. We aimed to study the learning of optical diagnosis for colorectal polyps. We studied five endoscopists as part of a randomized multisite trial comparing near-focus and standard-focus views for optical diagnosis. They trained using a computer-based module, followed by 10 real-time colonoscopies with pathology correlation. Endoscopists then optically diagnosed and resected all the polyps found during 558 consecutive colonoscopies, and diagnoses were compared with pathology. Endoscopists repeated the training module at the study midpoint. NPV and concordance of surveillance intervals for diminutive polyps diagnosed optically with high confidence were measured over time. Endoscopists showed high diagnostic performance, with a nonsignificant trend toward higher NPV in the second half of the study. For the 445 polyps in the standard-view arm, the NPV was 88.0 % (95 %CI 75.7 % - 95.5 %) in the first half and 95.8 % (88.3 % - 99.1 %) in the second; P = 0.7. Three endoscopists in the first half and four in the second achieved > 90 % NPV. Concordance of surveillance intervals was identical in the first and second halves at 98.1 % (95 %CI 93.3 % - 99.8 %). High NPV for the prediction of non-neoplasms with NBI was achieved and maintained in this group of endoscopists who participated in standardized and continued training. Both NPV and surveillance interval agreement indicated high performance in the optical diagnosis of colorectal polyps and exceeded thresholds. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Diagnostic accuracy of translucency rendering to differentiate polyps from pseudopolyps at 3D endoluminal CT colonography: a feasibility study.

    PubMed

    Guerrisi, A; Marin, D; Laghi, A; Di Martino, M; Iafrate, F; Iannaccone, R; Catalano, C; Passariello, R

    2010-08-01

    The aim of this study was to assess the accuracy of translucency rendering (TR) in computed tomographic (CT) colonography without cathartic preparation using primary 3D reading. From 350 patients with 482 endoscopically verified polyps, 50 pathologically proven polyps and 50 pseudopolyps were retrospectively examined. For faecal tagging, all patients ingested 140 ml of orally administered iodinated contrast agent (diatrizoate meglumine and diatrizoate sodium) at meals 48 h prior to CT colonography examination and two h prior to scanning. CT colonography was performed using a 64-section CT scanner. Colonoscopy with segmental unblinding was performed within 2 weeks after CT. Three independent radiologists retrospectively evaluated TRCT clonographic images using a dedicated software package (V3D-Colon System). To enable size-dependent statistical analysis, lesions were stratified into the following size categories: small (< or =5 mm), intermediate (6-9 mm), and large (> or =10 mm). Overall average TR sensitivity for polyp characterisation was 96.6%, and overall average specificity for pseudopolyp characterisation was 91.3%. Overall average diagnostic accuracy (area under the curve) of TR for characterising colonic lesions was 0.97. TR is an accurate tool that facilitates interpretation of images obtained with a primary 3D analysis, thus enabling easy differentiation of polyps from pseudopolyps.

  6. Sessile Serrated Polyps: Detection, Eradication, and Prevention of the Evil Twin

    PubMed Central

    Obuch, Joshua C.; Pigott, Courtney M.; Ahnen, Dennis J.

    2015-01-01

    Opinion Statement The sessile serrated polyp (SSP), also known as sessile serrated adenoma, is the evil twin among the colorectal cancer precursors. As will be described, these lesions have multiple aliases (serrated adenoma, serrated polyp or serrated lesion among others), they hang out in a bad neighborhood (the poorly prepped right colon), they hide behind a mask of mucus, they are difficult for witnesses (pathologists) to identify, they are difficult for police (endoscopists) to find, they are difficult to permanently remove from society (high incomplete resection rate), they can be impulsive (progress rapidly to CRC) and enforcers (gastroenterologists) don’t know how best to control them (uncertain surveillance recommendations). There is no wonder that there is a need to understand these lesions well, learn how best to prevent the colonic mucosa from going down this errant path or, if that fails, to detect these deviants and eradicate them from colonic society. These lesions should be on the endoscopists’ most wanted list. PMID:25623474

  7. Can optical diagnosis of small colon polyps be accurate? Comparing standard scope without narrow banding to high definition scope with narrow banding.

    PubMed

    Ashktorab, Hassan; Etaati, Firoozeh; Rezaeean, Farahnaz; Nouraie, Mehdi; Paydar, Mansour; Namin, Hassan Hassanzadeh; Sanderson, Andrew; Begum, Rehana; Alkhalloufi, Kawtar; Brim, Hassan; Laiyemo, Adeyinka O

    2016-07-28

    To study the accuracy of using high definition (HD) scope with narrow band imaging (NBI) vs standard white light colonoscope without NBI (ST), to predict the histology of the colon polyps, particularly those < 1 cm. A total of 147 African Americans patients who were referred to Howard University Hospital for screening or, diagnostic or follow up colonoscopy, during a 12-mo period in 2012 were prospectively recruited. Some patients had multiple polyps and total number of polyps was 179. Their colonoscopies were performed by 3 experienced endoscopists who determined the size and stated whether the polyps being removed were hyperplastic or adenomatous polyps using standard colonoscopes or high definition colonoscopes with NBI. The histopathologic diagnosis was reported by pathologists as part of routine care. Of participants in the study, 55 (37%) were male and median (interquartile range) of age was 56 (19-80). Demographic, clinical characteristics, past medical history of patients, and the data obtained by two instruments were not significantly different and two methods detected similar number of polyps. In ST scope 89% of polyps were < 1 cm vs 87% in HD scope (P = 0.7). The ST scope had a positive predictive value (PPV) and positive likelihood ratio (PLR) of 86% and 4.0 for adenoma compared to 74% and 2.6 for HD scope. There was a trend of higher sensitivity for HD scope (68%) compare to ST scope (53%) with almost the same specificity. The ST scope had a PPV and PLR of 38% and 1.8 for hyperplastic polyp (HPP) compared to 42% and 2.2 for HD scope. The sensitivity and specificity of two instruments for HPP diagnosis were similar. Our results indicated that HD scope was more sensitive in diagnosis of adenoma than ST scope. Clinical diagnosis of HPP with either scope is less accurate compared to adenoma. Colonoscopy diagnosis is not yet fully matched with pathologic diagnosis of colon polyp. However with the advancement of both imaging and training, it may be possible to increase the sensitivity and specificity of the scopes and hence save money for eliminating time and the cost of Immunohistochemistry/pathology.

  8. A comparison of detection efficiency on an air traffic control monitoring task with and without computer aiding.

    DOT National Transportation Integrated Search

    1989-01-01

    Future levels of air traffic control automation plan to incorporate computer aiding features designed to alert the controller to upcoming problem situations by displaying information that will identify the situation and suggest possible solutions. Co...

  9. The CIMP Phenotype in BRAF Mutant Serrated Polyps from a Prospective Colonoscopy Patient Cohort

    PubMed Central

    Fernando, Winnie C.; Miranda, Mariska S.; Worthley, Daniel L.; Togashi, Kazutomo; Watters, Dianne J.; Leggett, Barbara A.; Spring, Kevin J.

    2014-01-01

    Colorectal cancers arising via the serrated pathway are often associated with BRAF V600E mutation, CpG island methylator phenotype (CIMP), and microsatellite instability. Previous studies have shown a strong association between BRAF V600E mutation and serrated polyps. This study aims to evaluate CIMP status of all the serrated polyp subtypes and its association with functionally important genes such as MLH1, p16, and IGFBP7. CIMP status and methylation were evaluated using the real-time based MethyLight assay in 154 serrated polyps and 63 conventional adenomas. Results showed that CIMP-high serrated polyps were strongly associated with BRAF mutation and proximal colon. CIMP-high was uncommon in conventional adenomas (1.59%), occurred in 8.25% of hyperplastic polyps (HPs), and became common in sessile serrated adenomas (SSAs) (51.43%). MLH1 methylation was mainly observed in the proximal colon and was significantly associated with BRAF mutation and CIMP-high. The number of samples methylated for p16 and IGFBP7 was the highest in SSAs. The methylation panel we used to detect CIMP is highly specific for CIMP-high cancers. With this panel, we demonstrate that CIMP-high is much more common in SSAs than HPs. This suggests that CIMP-high correlates with increased risk of malignant transformation which was also observed in methylation of functionally important genes. PMID:24812557

  10. The CIMP Phenotype in BRAF Mutant Serrated Polyps from a Prospective Colonoscopy Patient Cohort.

    PubMed

    Fernando, Winnie C; Miranda, Mariska S; Worthley, Daniel L; Togashi, Kazutomo; Watters, Dianne J; Leggett, Barbara A; Spring, Kevin J

    2014-01-01

    Colorectal cancers arising via the serrated pathway are often associated with BRAF V600E mutation, CpG island methylator phenotype (CIMP), and microsatellite instability. Previous studies have shown a strong association between BRAF V600E mutation and serrated polyps. This study aims to evaluate CIMP status of all the serrated polyp subtypes and its association with functionally important genes such as MLH1, p16, and IGFBP7. CIMP status and methylation were evaluated using the real-time based MethyLight assay in 154 serrated polyps and 63 conventional adenomas. Results showed that CIMP-high serrated polyps were strongly associated with BRAF mutation and proximal colon. CIMP-high was uncommon in conventional adenomas (1.59%), occurred in 8.25% of hyperplastic polyps (HPs), and became common in sessile serrated adenomas (SSAs) (51.43%). MLH1 methylation was mainly observed in the proximal colon and was significantly associated with BRAF mutation and CIMP-high. The number of samples methylated for p16 and IGFBP7 was the highest in SSAs. The methylation panel we used to detect CIMP is highly specific for CIMP-high cancers. With this panel, we demonstrate that CIMP-high is much more common in SSAs than HPs. This suggests that CIMP-high correlates with increased risk of malignant transformation which was also observed in methylation of functionally important genes.

  11. Factors associated with perceived risk in automotive employees at increased risk of colorectal cancer.

    PubMed

    Vernon, S W; Myers, R E; Tilley, B C; Li, S

    2001-01-01

    Risk perception may be an important motivator of health-related behaviors. To develop effective risk communication messages, it is important to understand both the patterns of association between perceived risk and health-related behaviors as well as the correlates of risk perception. Very little is known about whether correlates of risk perception are similar in cross-sectional data compared with prospective data. Furthermore, there are scant data on consistency of correlates of risk perception across groups who vary in objective medical risk. If correlates differ, it would underscore the need to tailor intervention messages based on subgroup characteristics as well as increase awareness of the limitations of basing intervention messages only on cross-sectional data. We analyzed data on a subset of 5042 employees who participated in The Next Step Trial, a randomized health promotion trial to encourage colorectal cancer screening and dietary change. We restricted our analysis to only those automotive workers who were white, male, and did not have colorectal cancer (4477/5042) and who returned surveys both at baseline (2,684/4,477) and at year 2 of follow-up (1955/2684). Initial analyses detected interactions between a history of polyps and several of the other covariates. Therefore, univariate and multivariable analyses were conducted separately for men with and without a personal history of colorectal polyps. Within each of the four subgroups (those with or without polyps in the baseline or follow-up analyses), we examined associations between perceived risk measured at baseline (cross-sectional analyses) and at year 2 of follow-up (prospective analyses) in relation to intervention group status, demographic, medical history, psychosocial, and worksite characteristics measured at baseline. To assess the predictive ability of the models, we computed sensitivity and specificity as measures of each model's ability to correctly classify men into their respective subgroup. Although there was no association between perceived risk and intervention group status in the four subgroups analyzed, we included intervention group status as a covariate in all analyses. At baseline (cross-sectional analyses) among men with and without a history of polyps, perceived risk was positively associated with family history of colorectal polyps or cancer, family support for screening, and worry about being diagnosed with colorectal cancer. In addition, for men without polyps, perceived risk was positively associated with being a current smoker. At year 2 of follow-up (prospective analyses) for men with and without polyps, perceived risk at year 2 was positively associated with family history and baseline perceived risk and was negatively associated with having a normal screening examination or no examinations during the trial. In addition, for men with polyps, perceived risk was positively associated with belief in the salience and coherence of screening and with intention to be screened and was negatively associated with access to screening at the worksite. Specificity was higher than sensitivity in three of four subgroups and was >65% in all subgroups. Except for family history, messages to influence perceived risk would emphasize different factors, depending on whether associations were based on baseline or follow-up data and depending on whether men reported a personal history of polyps. For example, although intervention messages using baseline data would emphasize the same factors for men with or without polyps, messages based on follow-up data would emphasize psychosocial characteristics, such as salience and coherence of screening and intention for men with a history of polyps but not for men without. Our findings support the need to delineate subgroups in the study population to target and tailor health-related messages based on respondent characteristics. Our findings also underscore the need to base health-related messages on prospective data as well as cross-sectional data to better address health-related beliefs and behaviors.

  12. Total colonoscopy detects early colorectal cancer more frequently than advanced colorectal cancer in patients with fecal occult blood.

    PubMed

    Ozaki, Takuji; Tokunaga, Akira; Chihara, Naoto; Yoshino, Masanori; Bou, Hideki; Ogata, Masao; Watanabe, Masanori; Suzuki, Hideyuki; Uchida, Eiji

    2010-08-01

    The efficacy of total colonoscopy following a positive result of the fecal occult blood test (FOBT) for the early detection of colorectal cancer and polyps was evaluated. A total of 1,491 patients with positive FOBT results underwent total colonoscopy at the Institute of Gastroenterology, Nippon Medical School, Musashi Kosugi Hospital, from April 2002 through July 2009. Abnormalities were found in 1,312 of the 1,491 patients (88.0%). Ninety-six of the 1,491 patients (6.4%) were found to have early cancer, but 59 patients (4.0%) were found to have advanced cancer. The early cancers were treated with endoscopic mucosal resection or endoscopic submucosal dissection in 81 patients, with laparoscopy-assisted colectomy in 10 patients, and with open surgery in 5 patients. Fifty-one of the 59 patients with advanced colorectal cancer underwent conventional open surgery, and 8 patients underwent laparoscopic surgery. The cancers detected were more likely to be early cancers than advanced cancers. In addition to malignancies, other abnormalities found included inner or external hemorrhoids, diverticula of the colon, ulcerative colitis, ischemic colitis, infectious colitis, and colorectal polyps. Our results show that a high percentage of lesions detected with total colonoscopy following a positive FOBT result are early colorectal cancers and polyps.

  13. Accuracy of saline contrast sonohysterography in detection of endometrial polyps and submucosal leiomyomas in women of reproductive age with abnormal uterine bleeding: systematic review and meta-analysis.

    PubMed

    Bittencourt, C A; Dos Santos Simões, R; Bernardo, W M; Fuchs, L F P; Soares Júnior, J M; Pastore, A R; Baracat, E C

    2017-07-01

    To analyze the diagnostic accuracy of two- (2D) and three- (3D) dimensional saline contrast sonohysterography (SCSH) in the detection of endometrial polyps and submucosal uterine leiomyomas in women of reproductive age with abnormal uterine bleeding compared with gold standard hysteroscopy. A systematic review of diagnostic studies that compared 2D- and/or 3D-SCSH with hysteroscopy and anatomopathology was conducted according to PRISMA and SEDATE recommendations. The databases MEDLINE, EMBASE and The Cochrane Library were searched electronically using specific terms with no restriction on language or publication year. Quality assessment of included studies was performed using the QUADAS-2 tool. Meta-analysis was performed with the Meta-DiSk program and data presented as forest plots and summary receiver-operating characteristics (SROC) curves. Pooled sensitivity, specificity and positive (LR+) and negative (LR-) likelihood ratios of SCSH in the detection of uterine cavity abnormalities were calculated. A total of 1398 citations were identified and five studies were included in the systematic review and meta-analysis. Pooled sensitivity and specificity of 2D-SCSH in detecting endometrial polyps were 93% (95% CI, 89-96%) and 81% (95% CI, 76-86%), respectively, with pooled LR+ of 5.41 (95% CI, 2.60-11.28) and LR- of 0.10 (95% CI, 0.06-0.17). In the detection of submucosal uterine leiomyomas, pooled sensitivity and specificity were 94% (95% CI, 89-97%) and 81% (95% CI, 76-86%), respectively, with pooled LR+ of 4.25 (95% CI, 2.20-8.21) and LR- of 0.11 (95% CI, 0.05-0.22). 2D-SCSH had good accuracy in detecting endometrial polyps and submucosal uterine leiomyomas, with areas under the SROC curves of 0.97 ± 0.02 and 0.97 ± 0.03, respectively. Studies that analyzed the diagnostic accuracy of 3D-SCSH could not be compared due to high heterogeneity related to menopausal status, type of technique used and primary outcome being investigation of infertility. 2D-SCSH proved to be a highly sensitive method for detection of endometrial polyps and submucosal uterine leiomyomas, making it a potential first-line diagnostic method in the work-up for women with abnormal uterine bleeding. More studies are needed on 3D-SCSH in women of reproductive age. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

  14. Dynamic enhanced computed tomography imaging findings of an inflammatory fibroid polyp with massive fibrosis in the stomach

    PubMed Central

    Shim, Eun Jung; Ahn, Sung Eun; Lee, Dong Ho; Park, Seong Jin; Kim, Youn Wha

    2017-01-01

    Inflammatory fibroid polyp (IFP) is a rare benign lesion of the gastrointestinal tract. We report a case of computed tomography (CT) imaging finding of a gastric IFP with massive fibrosis. CT scans showed thickening of submucosal layer with overlying mucosal hyperenhancement in the gastric antrum. The submucosal layer showed increased enhancement on delayed phase imaging. An antrectomy with gastroduodenostomy was performed because gastric cancer was suspected, particularly signet ring cell carcinoma. The histopathological diagnosis was an IFP with massive fibrosis. The authors suggest that when the submucosal layer of the gastric wall is markedly thickened with delayed enhancement and preservation of the mucosal layer, an IFP with massive fibrosis should be considered in the differential diagnosis. PMID:28373777

  15. Development of a Computer-aided Diagnosis System for Early Detection of Masses Using Retrospectively Detected Cancers on Prior Mammograms

    DTIC Science & Technology

    2009-06-01

    131 cases with 131 biopsy proven masses, of which 27 were malignant and 104 benign. The true locations of the masses were identified by an experi- enced ...two acquisitions would cause differ- ences in the subtlety of the masses on the FFDMs and SFMs. However, assuming that the differences are ran- dom... Lado , M. Souto, and J. J. Vidal, “Computer-aided diagnosis: Automatic detection of malignant masses in digitized mammograms,” Med. Phys. 25, 957–964

  16. Reducing false-positive detections by combining two stage-1 computer-aided mass detection algorithms

    NASA Astrophysics Data System (ADS)

    Bedard, Noah D.; Sampat, Mehul P.; Stokes, Patrick A.; Markey, Mia K.

    2006-03-01

    In this paper we present a strategy for reducing the number of false-positives in computer-aided mass detection. Our approach is to only mark "consensus" detections from among the suspicious sites identified by different "stage-1" detection algorithms. By "stage-1" we mean that each of the Computer-aided Detection (CADe) algorithms is designed to operate with high sensitivity, allowing for a large number of false positives. In this study, two mass detection methods were used: (1) Heath and Bowyer's algorithm based on the average fraction under the minimum filter (AFUM) and (2) a low-threshold bi-lateral subtraction algorithm. The two methods were applied separately to a set of images from the Digital Database for Screening Mammography (DDSM) to obtain paired sets of mass candidates. The consensus mass candidates for each image were identified by a logical "and" operation of the two CADe algorithms so as to eliminate regions of suspicion that were not independently identified by both techniques. It was shown that by combining the evidence from the AFUM filter method with that obtained from bi-lateral subtraction, the same sensitivity could be reached with fewer false-positives per image relative to using the AFUM filter alone.

  17. Computer-Aided Detection of Prostate Cancer with MRI: Technology and Applications

    PubMed Central

    Liu, Lizhi; Tian, Zhiqiang; Zhang, Zhenfeng; Fei, Baowei

    2016-01-01

    One in six men will develop prostate cancer in his life time. Early detection and accurate diagnosis of the disease can improve cancer survival and reduce treatment costs. Recently, imaging of prostate cancer has greatly advanced since the introduction of multi-parametric magnetic resonance imaging (mp-MRI). Mp-MRI consists of T2-weighted sequences combined with functional sequences including dynamic contrast-enhanced MRI, diffusion-weighted MRI, and MR spectroscopy imaging. Due to the big data and variations in imaging sequences, detection can be affected by multiple factors such as observer variability and visibility and complexity of the lesions. In order to improve quantitative assessment of the disease, various computer-aided detection systems have been designed to help radiologists in their clinical practice. This review paper presents an overview of literatures on computer-aided detection of prostate cancer with mp-MRI, which include the technology and its applications. The aim of the survey is threefold: an introduction for those new to the field, an overview for those working in the field, and a reference for those searching for literature on a specific application. PMID:27133005

  18. Quality of colonoscopy performance among gastroenterology and surgical trainees: a need for common training standards for all trainees?

    PubMed

    Leyden, J E; Doherty, G A; Hanley, A; McNamara, D A; Shields, C; Leader, M; Murray, F E; Patchett, S E; Harewood, G C

    2011-11-01

    Cecal intubation and polyp detection rates are objective measures of colonoscopy performance. Minimum cecal intubation rates greater than 90% have been endorsed by the American Society for Gastrointestinal Endoscopy (ASGE) and the Joint Advisory Group (JAG) UK. Performance data for medical and surgical trainee endoscopists are limited, and we used endoscopy quality parameters to compare these two groups. Retrospective review of all single-endoscopist colonoscopies done by gastroenterology and surgical trainees ("registrars," equivalent to fellows, postgraduate year 5) with more than two years' endoscopy experience, in 2006 and 2007 at a single academic medical center. Completion rates and polyp detection rates for endoscopists performing more than 50 colonoscopies during the study period were audited. Colonoscopy withdrawal time was prospectively observed in a representative subset of 140 patients. Among 3079 audited single-endoscopist colonoscopies, seven gastroenterology trainees performed 1998 procedures and six surgery trainees performed 1081. The crude completion rate was 82%, 84% for gastroenterology trainees and 78% for surgery trainees (P < 0.0001). Adjusted for poor bowel preparation quality and obstructing lesions, the completion rate was 89%; 93% for gastroenterology trainees, and 84% for surgical trainees (P < 0.0001). The polyp detection rate was 19% overall, with 21% and 14% for gastroenterology and surgical trainees, respectively (P < 0.0001). The adenoma detection rate in patients over 50 was 12%; gastroenterology trainees 14% and surgical trainees 9% (P = 0.0065). In the prospectively audited procedures, median withdrawal time was greater in the gastroenterology trainee group and polyp detection rates correlated closely with withdrawal time (r = 0.99). The observed disparity in endoscopic performance between surgical and gastroenterology trainees suggests the need for a combined or unitary approach to endoscopy training for specialist medical and surgical trainees. © Georg Thieme Verlag KG Stuttgart · New York.

  19. Increasing Navigation Speed at Endoluminal CT Colonography Reduces Colonic Visualization and Polyp Identification.

    PubMed

    Plumb, Andrew A; Phillips, Peter; Spence, Graeme; Mallett, Susan; Taylor, Stuart A; Halligan, Steve; Fanshawe, Thomas

    2017-08-01

    Purpose To investigate the effect of increasing navigation speed on the visual search and decision making during polyp identification for computed tomography (CT) colonography Materials and Methods Institutional review board permission was obtained to use deidentified CT colonography data for this prospective reader study. After obtaining informed consent from the readers, 12 CT colonography fly-through examinations that depicted eight polyps were presented at four different fixed navigation speeds to 23 radiologists. Speeds ranged from 1 cm/sec to 4.5 cm/sec. Gaze position was tracked by using an infrared eye tracker, and readers indicated that they saw a polyp by clicking a mouse. Patterns of searching and decision making by speed were investigated graphically and by multilevel modeling. Results Readers identified polyps correctly in 56 of 77 (72.7%) of viewings at the slowest speed but in only 137 of 225 (60.9%) of viewings at the fastest speed (P = .004). They also identified fewer false-positive features at faster speeds (42 of 115; 36.5%) of videos at slowest speed, 89 of 345 (25.8%) at fastest, P = .02). Gaze location was highly concentrated toward the central quarter of the screen area at faster speeds (mean gaze points at slowest speed vs fastest speed, 86% vs 97%, respectively). Conclusion Faster navigation speed at endoluminal CT colonography led to progressive restriction of visual search patterns. Greater speed also reduced both true-positive and false-positive colorectal polyp identification. © RSNA, 2017 Online supplemental material is available for this article.

  20. [Virtual colonoscopy is now reality].

    PubMed

    Pedersen, Bodil Ginnerup; Achiam, Michael P; Arnesen, Regnar Bøge

    2005-10-31

    Virtual colonoscopy involves a helical CT or MR scan of the abdomen and pelvis to detect colorectal polyps and cancer. Both modalities have shown promising sensitivity in revealing larger polyps, in comparison with colonoscopy. Caution should be exercised in its clinical implementation due to significant interobserver variation and individual learning curves. A Danish study indicates that CT colonography (CTC) can be performed cost-effectively compared to colonoscopy. CTC is recommended in preference to double-contrast barium enema after incomplete colonoscopy.

  1. [The role of colonoscopy in early diagnosis of intraluminal recurrences in patients already treated for colorectal cancer].

    PubMed

    Barillari, P; Manetti, G; Bovino, A; Puce, Y; Piovanello, P; Cioè, I; Sammartino, P; Stipa, V

    1996-11-01

    It is a common opinion that the more often and the more rigorously the colon is examined, the more lesions will be discovered and diagnosed. However it has not been shown which methods of colonic examination and which regimen of surveillance should be used. Chart review was conducted on 481 patients who underwent curative resection for colorectal cancer between 1980 and 1990. Colonoscopy was performed preoperatively, after 12-15 months from surgical treatment, and then at an interval of 12-24 months, or when symptoms appeared. About ten percent of patients developed intraluminal recurrences, and more than 25% adenomatous polyps. More than one half of the metachronous lesions arise within the first 24 months. The median time to diagnosis was 25 months for intraluminal recurrences and 22 months for adenomatous polyps. Patients with left sited tumor at an advanced stage run a higher risk of developing recurrent intraluminal disease, and patients who presented associated polyps at the time of the operation for the index cancer have a higher risk of developing new polyps. About 50% of recurrences were detected when patients were asymptomatic. Colonoscopy must be performed within the first 12-15 months after operation, while an interval of 24 months between each examination seems sufficient to guarantee an early detection of metachronous lesion. Asymptomatic patients are more frequently reoperated for cure and thus have a better survival rate.

  2. Matching colonoscopy and pathology data in population-based registries: development of a novel algorithm and the initial experience of the New Hampshire Colonoscopy Registry.

    PubMed

    Greene, Mary Ann; Butterly, Lynn F; Goodrich, Martha; Onega, Tracy; Baron, John A; Lieberman, David A; Dietrich, Allen J; Srivastava, Amitabh

    2011-08-01

    The quality of polyp-level data in a population-based registry depends on the ability to match each polypectomy recorded by the endoscopist to a specific diagnosis on the pathology report. To review impediments encountered in matching colonoscopy and pathology data in a population-based registry. New Hampshire Colonoscopy Registry data from August 2006 to November 2008 were analyzed for prevalence of missing reports, discrepancies between colonoscopy and pathology reports, and the proportion of polyps that could not be matched because of multiple polyps submitted in the same container. New Hampshire Colonoscopy Registry. This study involved all consenting patients during the study period. Develop an algorithm for capturing number, size, location, and histology of polyps and for defining and flagging discrepancies to ensure data quality. The proportion of polyps with no assumption or discrepancy, the proportion of patient records eligible for determining the adenoma detection rate (ADR), and the number of patients with ≥3 adenomas. Only 50% of polyps removed during this period were perfectly matched, with no assumption or discrepancy. Records from only 69.9% and 29.7% of eligible patients could be used to determine the ADR and the number of patients with ≥3 adenomas, respectively. Rates of missing reports may have been higher in the early phase of establishment of the registry. This study highlights the impediments in collecting polyp-level data in a population-based registry and provides useful parameters for evaluating the quality and accuracy of data obtained from such registries. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  3. High prevalence of adenomatous colorectal polyps in young cancer survivors treated with abdominal radiation therapy: results of a prospective trial.

    PubMed

    Daly, Patricia E; Samiee, Sara; Cino, Maria; Gryfe, Robert; Pollett, Aaron; Ng, Andrea; Constine, Louis S; Hodgson, David C

    2017-10-01

    Cancer survivors treated with abdominal/pelvic radiation therapy (ART) have increased the risks of colorectal cancer (CRC), although evidence supporting early CRC screening for these patients is lacking. We sought to determine whether there is an elevated prevalence of adenomatous colorectal polyps in young survivors prior to the age when screening would be routinely recommended. We conducted a prospective study of early colonoscopic screening in cancer survivors aged 35-49 who had received ART ≥10 years previously. The planned sample size was based on prior studies reporting a prevalence of adenomatous polyps of approximately 20% among the average-risk population ≥50 years of age, in contrast to ≤10% among those average-risk people aged 40-50 years, for whom screening is not routinely recommended. Colonoscopy was performed in 54 survivors, at a median age of 45 years (range 36-49) and after median interval from radiation treatment of 19 years (10.6-43.5). Forty-nine polyps were detected in 24 patients, with 15 patients (27.8%; 95% CI 17.6% to 40.9%) having potentially precancerous polyps. Fifty-three per cent of polyps were within or at the edge of the prior ART fields. Young survivors treated with ART have a polyp prevalence comparable with the average-risk population aged ≥50 years and substantially higher than previously reported for the average-risk population aged 40-50 years. These findings lend support to the early initiation of screening in these survivors. NCT00982059; results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  4. Multicentric GISCoR Study "intensive clinical follow-up versus surgical radicalization after complete endoscopic polypectomy of a malignant adenoma" (SEC-GISCoR).

    PubMed

    Andreoni, Bruno; Camellini, Lorenzo; Sonzogni, Angelica; Crosta, Cristiano; Pirola, Maria Elena; Corbellini, Carlo

    2011-09-01

    Colorectal cancer screening programs result in an early diagnosis of the disease. In 2007, 250 malignant polyps were identified in Lombardy, out of 1,329 screen-detected colorectal carcinomas. The Italian Group for Colorectal Cancer (GISCoR) promoted the multicentric study "Endoscopic Follow-up versus Surgical Radicalization of Malignant Polyps after Complete Endoscopic Polypectomy" (SEC-GISCoR). The protocol was a multicentric, prospective, observational, non-randomized study. It included patients diagnosed a colorectal malignant adenoma, after complete endoscopic removal. From November 2005 to September 2009, three participating centers enrolled 120 patients with malignant polyps after "complete" endoscopic polypectomy; malignant polyps were classified as "low risk" or "high risk". The study had two arms: "Intensive follow-up" (42 patients: 32 with low-risk and 10 with high-risk polyps) and "Surgical radicalization" (78 patients: 5 with low-risk and 73 with high-risk polyps). Data were collected using an online CRF. Overall, 37/120 polyps (30.8%) were low risk and 83/120 (69.2%) were high risk. 42 out of 120 patients (35%) were enrolled in the "clinical follow-up" arm, while 78/120 (65%) entered the surgery arm. In 15 cases, patients were not enrolled in the correct arm, according to the criteria agreed upon before starting the study. There still is a high incidence (11.5%) of pathological mismatches. No clinical event was reported in 2.9 years of follow-up. In conclusion, some differences emerged in the management of patients with malignant polyps among participating centers (p < 0.001), mismatches can be explained by high surgical risk or patient's choice. Only in 5 cases (4.2%), did data analysis not allow to exactly determine the reason for a choice different from protocol criteria. The availability of new risk factors and the evidence of pathological mismatches confirmed the need for future studies on this issue.

  5. Evaluation of a novel tablet application for improvement in colonoscopy training and mentoring (with video).

    PubMed

    Laborde, Cregan J; Bell, Charreau S; Slaughter, James Chris; Valdastri, Pietro; Obstein, Keith L

    2017-03-01

    Endoscopic training can be challenging for the trainee and preceptor. Frustration can result from ineffective communication regarding areas of interest. Our team developed a novel tablet application for real-time mirroring of the colonoscopy examination that allows preceptors to make annotations directly on the viewing monitor. The potential for improvement in team proficiency and satisfaction is unknown. The on-screen endoscopic image is mirrored to an Android tablet and permits real-time annotation directly on the in-room endoscopic image display. Preceptors can also "freeze-frame" an image and provide visual on-screen instruction (telestration). Trainees, precepted by a GI attending, were 1:1 randomized to perform colonoscopy on a training phantom using the application with traditional precepting or traditional precepting alone. Magnetized polyps (size < 5 mm) were placed in 1 of 5 preset location scenarios. Each trainee performed a total of 10 colonoscopies and completed each location scenario twice. During withdrawal, the trainee and the attending identified polyps. Outcome measures included number of polyps missed and participant satisfaction after each trial. Fifteen trainees (6 novice and 9 GI fellows) performed a total of 150 colonoscopies where 330 polyps in total were placed. Fellows missed fewer polyps using the tablet versus traditional precepting alone (4.2% vs 12.5%; P = .04). There was no significant difference in missed polyps for novices (12.5% vs 18.8%; P = .66). Overall, fellows missed fewer polyps when compared with novices regardless of the precepting method (P = .01). The attending and all trainees reported reduced stress with improved communication using the tablet. Fellows missed fewer polyps using the tablet when compared with traditional endoscopy precepting. All trainees reported reduced stress, quicker identification of polyps, and improved educational satisfaction using the tablet. Our application has the potential to improve trainee plus attending team lesion detection and to enhance the endoscopy training experience for both the trainee and attending preceptor. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  6. Computer aided detection system for lung cancer using computer tomography scans

    NASA Astrophysics Data System (ADS)

    Mahesh, Shanthi; Rakesh, Spoorthi; Patil, Vidya C.

    2018-04-01

    Lung Cancer is a disease can be defined as uncontrolled cell growth in tissues of the lung. If we detect the Lung Cancer in its early stage, then that could be the key of its cure. In this work the non-invasive methods are studied for assisting in nodule detection. It supplies a Computer Aided Diagnosis System (CAD) for early detection of lung cancer nodules from the Computer Tomography (CT) images. CAD system is the one which helps to improve the diagnostic performance of radiologists in their image interpretations. The main aim of this technique is to develop a CAD system for finding the lung cancer using the lung CT images and classify the nodule as Benign or Malignant. For classifying cancer cells, SVM classifier is used. Here, image processing techniques have been used to de-noise, to enhance, for segmentation and edge detection of an image is used to extract the area, perimeter and shape of nodule. The core factors of this research are Image quality and accuracy.

  7. Can optical diagnosis of small colon polyps be accurate? Comparing standard scope without narrow banding to high definition scope with narrow banding

    PubMed Central

    Ashktorab, Hassan; Etaati, Firoozeh; Rezaeean, Farahnaz; Nouraie, Mehdi; Paydar, Mansour; Namin, Hassan Hassanzadeh; Sanderson, Andrew; Begum, Rehana; Alkhalloufi, Kawtar; Brim, Hassan; Laiyemo, Adeyinka O

    2016-01-01

    AIM: To study the accuracy of using high definition (HD) scope with narrow band imaging (NBI) vs standard white light colonoscope without NBI (ST), to predict the histology of the colon polyps, particularly those < 1 cm. METHODS: A total of 147 African Americans patients who were referred to Howard University Hospital for screening or, diagnostic or follow up colonoscopy, during a 12-mo period in 2012 were prospectively recruited. Some patients had multiple polyps and total number of polyps was 179. Their colonoscopies were performed by 3 experienced endoscopists who determined the size and stated whether the polyps being removed were hyperplastic or adenomatous polyps using standard colonoscopes or high definition colonoscopes with NBI. The histopathologic diagnosis was reported by pathologists as part of routine care. RESULTS: Of participants in the study, 55 (37%) were male and median (interquartile range) of age was 56 (19-80). Demographic, clinical characteristics, past medical history of patients, and the data obtained by two instruments were not significantly different and two methods detected similar number of polyps. In ST scope 89% of polyps were < 1 cm vs 87% in HD scope (P = 0.7). The ST scope had a positive predictive value (PPV) and positive likelihood ratio (PLR) of 86% and 4.0 for adenoma compared to 74% and 2.6 for HD scope. There was a trend of higher sensitivity for HD scope (68%) compare to ST scope (53%) with almost the same specificity. The ST scope had a PPV and PLR of 38% and 1.8 for hyperplastic polyp (HPP) compared to 42% and 2.2 for HD scope. The sensitivity and specificity of two instruments for HPP diagnosis were similar. CONCLUSION: Our results indicated that HD scope was more sensitive in diagnosis of adenoma than ST scope. Clinical diagnosis of HPP with either scope is less accurate compared to adenoma. Colonoscopy diagnosis is not yet fully matched with pathologic diagnosis of colon polyp. However with the advancement of both imaging and training, it may be possible to increase the sensitivity and specificity of the scopes and hence save money for eliminating time and the cost of Immunohistochemistry/pathology. PMID:27605888

  8. Comparing the Effects of Symbiotic Algae (Symbiodinium) Clades C1 and D on Early Growth Stages of Acropora tenuis

    PubMed Central

    Yuyama, Ikuko; Higuchi, Tomihiko

    2014-01-01

    Reef-building corals switch endosymbiotic algae of the genus Symbiodinium during their early growth stages and during bleaching events. Clade C Symbiodinium algae are dominant in corals, although other clades — including A and D — have also been commonly detected in juvenile Acroporid corals. Previous studies have been reported that only molecular data of Symbiodinium clade were identified within field corals. In this study, we inoculated aposymbiotic juvenile polyps with cultures of clades C1 and D Symbiodinium algae, and investigated the different effect of these two clades of Symbiodinium on juvenile polyps. Our results showed that clade C1 algae did not grow, while clade D algae grew rapidly during the first 2 months after inoculation. Polyps associated with clade C1 algae exhibited bright green fluorescence across the body and tentacles after inoculation. The growth rate of polyp skeletons was lower in polyps associated with clade C1 algae than those associated with clade D algae. On the other hand, antioxidant activity (catalase) of corals was not significantly different between corals with clade C1 and clade D algae. Our results suggested that clade D Symbiodinium algae easily form symbiotic relationships with corals and that these algae could contribute to coral growth in early symbiosis stages. PMID:24914677

  9. The gastrointestinal manifestation of constitutional mismatch repair deficiency syndrome: from a single adenoma to polyposis-like phenotype and early onset cancer.

    PubMed

    Levi, Z; Kariv, R; Barnes-Kedar, I; Goldberg, Y; Half, E; Morgentern, S; Eli, B; Baris, H N; Vilkin, A; Belfer, R G; Niv, Y; Elhasid, R; Dvir, R; Abu-Freha, N; Cohen, S

    2015-11-01

    Data on the clinical presentation of constitutional mismatch repair deficiency syndrome (CMMRD) is accumulating. However, as the extraintestinal manifestations are often fatal and occur at early age, data on the systematic evaluation of the gastrointestinal tract is scarce. Here we describe 11 subjects with verified biallelic carriage and who underwent colonoscopy, upper endoscopy and small bowel evaluation. Five subjects were symptomatic and in six subjects the findings were screen detected. Two subjects had colorectal cancer and few adenomatous polyps (19, 20 years), three subjects had polyposis-like phenotype (13, 14, 16 years), four subjects had few adenomatous polyps (8, 12-14 years) and two subjects had no polyps (both at age 6). Of the three subjects in the polyposis-like group, two subjects had already developed high-grade dysplasia or cancer and one subject had atypical juvenile polyps suggesting juvenile polyposis. Three out of the five subjects that underwent repeated exams had significant findings during short interval. The gastrointestinal manifestations of CMMRD are highly dependent upon age of examination and highly variable. The polyps may also resemble juvenile polyposis. Intensive surveillance according to current guidelines is mandatory. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Thyroid Ultrasound Pitfalls: Esophageal Fibrovascular Polyp Mimicking Thyroid Nodule

    PubMed Central

    Brigante, G.; Madeo, B.

    2016-01-01

    Background. Ultrasound (US) is the most accurate tool in the diagnosis of thyroid nodules if performed by expert physician. Misdiagnosis due to extrathyroidal lesions mimicking thyroid nodules is reported in literature. We describe the first case of an esophageal fibrovascular polyp misdiagnosed as a thyroid nodule on US examination. Patient Findings. A 54-year-old woman presented to emergency department for headache and underwent carotid Doppler extended to neck ultrasound with incidental finding of a nodule in the posterior side of the left thyroid lobe. A following thyroid US performed by an endocrinologist allowed the characterization of the lesion as an esophageal pathology, considering the extrathyroidal position, the typical peripheral hyperechoic spots and hypoechoic rim, the connection to the esophagus, and the swallowing connected movement. The patient was addressed to further investigations and finally to anterior pharyngotomy with histological diagnosis of esophageal fibrovascular polyp. Summary. Differential diagnosis between thyroid nodules and other neck lesions is important to prevent an unnecessary fine needle aspiration biopsy and to treat the extrathyroidal pathology. In this case, an US performed by an expert endocrinologist allowed detecting an esophageal fibrovascular polyp requiring surgical removal. In conclusion, the possibility of an esophageal pathology, and even fibrovascular polyp, should be considered during US thyroid examination. PMID:27022492

  11. [The crypto-hem test in screening for colon cancer].

    PubMed

    Prokorov, V V; Shabarov, V L

    1988-01-01

    The paper discusses the reliability of crypto-hem test (detection of occult blood in feces) in diagnosing large bowel tumors in the course of a mass screening. 1573 healthy subjects aged 45 years and older were examined. The results were positive in 24 (2%) out of 1190 screenees who were involved in the test and in 58 (4.9%) subjects the results were suspicious. Tumors were detected in 23 (95.9%) test-positive screenees: cancer--12.5, polyps--54.2 and villous tumor--29.2%. Crypto-hem test proved instrumental in mass screening. Due to its application, symptom-free rectal cancer was diagnosed in 0.2, villous tumor--0.6, and single adenomatous polyps--1.1%.

  12. Needle knife-assisted endoscopic polypectomy for a large inflammatory fibroid colon polyp by making its stalk into an omega shape using an endoloop.

    PubMed

    Kim, Byung Chang; Cheon, Jae Hee; Lee, Sang Kil; Kim, Tae Il; Kim, Hoguen; Kim, Won Ho

    2008-08-30

    Colonic inflammatory fibroid polyp (IFP) is an uncommon benign polypoid lesion, which is composed of fibroblasts, numerous small vessels and edematous connective tissue with marked eosinophilic inflammatory cell infiltration. This condition is frequently detected in the stomach and small intestine, but uncommon in the colon. Although IFP is a benign lesion, surgical resections are performed in most colonic cases because the polyps are usually too large to resect endoscopically. Only three patients underwent endoscopic polypectomy in our literature reviews. Here, we present a case of IFP in the descending colon successful endoscopically resected using a novel technique of trapping its stalk with an endoloop, forming the stalk into an omega shape, and then dissecting the stalk with a needle knife.

  13. Computer-Aided Methodology for Syndromic Strabismus Diagnosis.

    PubMed

    Sousa de Almeida, João Dallyson; Silva, Aristófanes Corrêa; Teixeira, Jorge Antonio Meireles; Paiva, Anselmo Cardoso; Gattass, Marcelo

    2015-08-01

    Strabismus is a pathology that affects approximately 4 % of the population, causing aesthetic problems reversible at any age and irreversible sensory alterations that modify the vision mechanism. The Hirschberg test is one type of examination for detecting this pathology. Computer-aided detection/diagnosis is being used with relative success to aid health professionals. Nevertheless, the routine use of high-tech devices for aiding ophthalmological diagnosis and therapy is not a reality within the subspecialty of strabismus. Thus, this work presents a methodology to aid in diagnosis of syndromic strabismus through digital imaging. Two hundred images belonging to 40 patients previously diagnosed by an specialist were tested. The method was demonstrated to be 88 % accurate in esotropias identification (ET), 100 % for exotropias (XT), 80.33 % for hypertropias (HT), and 83.33 % for hypotropias (HoT). The overall average error was 5.6Δ and 3.83Δ for horizontal and vertical deviations, respectively, against the measures presented by the specialist.

  14. Charity colonoscopy event to commemorate the 185th anniversary of Singapore General Hospital.

    PubMed

    Ng, Kheng Hong; Lim, Jit Fong; Ho, Kok Sun; Ooi, Boon Swee; Tang, Choong Leong; Eu, Kong Weng

    2008-03-01

    Colorectal cancer is now the cancer with the highest incidence in Singapore. However, the overall mortality rate is still about 50% because the majority of the patients present at a late stage of disease. A charity event of screening colonoscopy was offered to the public in conjunction with the 185th anniversary of Singapore General Hospital. The aim of this event was to raise awareness about early detection of colorectal cancer and the safety of colonoscopy. We conducted a one-off free screening event for colorectal cancer using colonoscopy. Four hundred and ninety individuals responded to a multimedia advertisement for the event. Of these, 220 individuals were selected for the screening based on National Guidelines for colorectal cancer screening and financial status. One hundred and fifty-two individuals turned up for the colonoscopy. The median age was 55 years (range, 22 to 82), with 84 males. Significant pathology was found in 33% of the individuals (n = 51). Colorectal polyps were detected in 34 individuals (22%). A total of 45 polyps were removed, with 20 hyperplastic polyps and 25 adenomas. Eight out of 25 adenomas were located proximal to the splenic flexure. Rectal cancer was diagnosed in 1 individual (0.6%). One individual had a large dysplastic rectosigmoid ulcer and refused further intervention. There were no significant complications from any of the colonoscopies. Colonoscopy is an invaluable screening modality as it has a high pick-up rate for colorectal polyp and cancer in an asymptomatic population. It is also proven to be safe in our study. It has the added advantage over flexible sigmoidoscopy of detecting a significant number of proximal lesions. Also, therapeutic polypectomy can be performed in the same setting.

  15. The effect on colon visualization during colonoscopy of the addition of simethicone to polyethylene glycol-electrolyte solution: a randomized single-blind study.

    PubMed

    Matro, Rebecca; Tupchong, Keegan; Daskalakis, Constantine; Gordon, Victoria; Katz, Leo; Kastenberg, David

    2012-11-29

    Colonic bubbles associated with polyethylene glycol-electrolyte solution (PEG-ELS) are common and obscure mucosal visualization. This study aimed to determine whether adding simethicone decreases the incidence of bubbles. Prospective, single-blind, randomized comparison of split dose PEG-ELS vs. PEG-ELS+simethicone (PEG-S) for outpatient colonoscopy. Bubble severity for colonic segments was assessed on withdrawal as A=no/minimal bubbles, B=moderate bubbles/interfere with detecting 5 mm polyp, C=severe bubbles/interfere with detecting 10 mm polyp. Primary end point was Grade B or C bubbles in any colon segment. Secondary end points were cleansing quality, incidence and severity of side effects, and polyp detection. One hundred and thirty nine patients enrolled; 13 withdrew before colonoscopy. Of 123 patients evaluated, 62 took PEG-S and 61 PEG-ELS. The incidence of grade B or C bubbles was much lower with PEG-S compared with PEG-ELS (2% vs. 38%; P=0.001). Overall cleansing (excellent or good) quality was not significantly different for either the whole colon (89% PEG-ELS, 94% of PEG-S, P=0.529) or right colon (88% PEG-ELS, 94% PEG-S, P=0.365). More PEG-S patients had excellent rather than good preps (whole colon 53% vs. 28%, P=0.004; right colon 53% vs. 35%, P=0.044). Need for any flushing was less with PEG-S (38% vs. 70%, P=0.001). The groups were not significantly different with respect to total procedure and withdrawal times, incidence or severity of side effects, or number of polyps/patient or adenomas/patient. Adding simethicone to PEG-ELS effectively eliminates bubbles, substantially reduces the need for flushing, and results in more excellent preparations.

  16. The Effect on Colon Visualization During Colonoscopy of the Addition of Simethicone to Polyethylene Glycol-Electrolyte Solution: A Randomized Single-Blind Study

    PubMed Central

    Matro, Rebecca; Tupchong, Keegan; Daskalakis, Constantine; Gordon, Victoria; Katz, Leo; Kastenberg, David

    2012-01-01

    OBJECTIVES: Colonic bubbles associated with polyethylene glycol-electrolyte solution (PEG-ELS) are common and obscure mucosal visualization. This study aimed to determine whether adding simethicone decreases the incidence of bubbles. METHODS: Prospective, single-blind, randomized comparison of split dose PEG-ELS vs. PEG-ELS+simethicone (PEG-S) for outpatient colonoscopy. Bubble severity for colonic segments was assessed on withdrawal as A=no/minimal bubbles, B=moderate bubbles/interfere with detecting 5 mm polyp, C=severe bubbles/interfere with detecting 10 mm polyp. Primary end point was Grade B or C bubbles in any colon segment. Secondary end points were cleansing quality, incidence and severity of side effects, and polyp detection. RESULTS: One hundred and thirty nine patients enrolled; 13 withdrew before colonoscopy. Of 123 patients evaluated, 62 took PEG-S and 61 PEG-ELS. The incidence of grade B or C bubbles was much lower with PEG-S compared with PEG-ELS (2% vs. 38% P=0.001). Overall cleansing (excellent or good) quality was not significantly different for either the whole colon (89% PEG-ELS, 94% of PEG-S, P=0.529) or right colon (88% PEG-ELS, 94% PEG-S, P=0.365). More PEG-S patients had excellent rather than good preps (whole colon 53% vs. 28%, P=0.004; right colon 53% vs. 35%, P=0.044). Need for any flushing was less with PEG-S (38% vs. 70%, P=0.001). The groups were not significantly different with respect to total procedure and withdrawal times, incidence or severity of side effects, or number of polyps/patient or adenomas/patient. CONCLUSIONS: Adding simethicone to PEG-ELS effectively eliminates bubbles, substantially reduces the need for flushing, and results in more excellent preparations. PMID:23238113

  17. Computer-aided Detection of Prostate Cancer with MRI: Technology and Applications.

    PubMed

    Liu, Lizhi; Tian, Zhiqiang; Zhang, Zhenfeng; Fei, Baowei

    2016-08-01

    One in six men will develop prostate cancer in his lifetime. Early detection and accurate diagnosis of the disease can improve cancer survival and reduce treatment costs. Recently, imaging of prostate cancer has greatly advanced since the introduction of multiparametric magnetic resonance imaging (mp-MRI). Mp-MRI consists of T2-weighted sequences combined with functional sequences including dynamic contrast-enhanced MRI, diffusion-weighted MRI, and magnetic resonance spectroscopy imaging. Because of the big data and variations in imaging sequences, detection can be affected by multiple factors such as observer variability and visibility and complexity of the lesions. To improve quantitative assessment of the disease, various computer-aided detection systems have been designed to help radiologists in their clinical practice. This review paper presents an overview of literatures on computer-aided detection of prostate cancer with mp-MRI, which include the technology and its applications. The aim of the survey is threefold: an introduction for those new to the field, an overview for those working in the field, and a reference for those searching for literature on a specific application. Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  18. Feasibility of full-spectrum endoscopy: Korea’s first full-spectrum endoscopy colonoscopic trial

    PubMed Central

    Song, Jeong-Yeop; Cho, Youn Hee; Kim, Mi A; Kim, Jeong-Ae; Lee, Chun Tek; Lee, Moon Sung

    2016-01-01

    AIM: To evaluate the full-spectrum endoscopy (FUSE) colonoscopy system as the first report on the utility thereof in a Korean population. METHODS: We explored the efficacy of the FUSE colonoscopy in a retrospective, single-center feasibility study performed between February 1 and July 20, 2015. A total of 262 subjects (age range: 22-80) underwent the FUSE colonoscopy for colorectal cancer screening, polyp surveillance, or diagnostic evaluation. The cecal intubation success rate, the polyp detection rate (PDR), the adenoma detection rate (ADR), and the diverticulum detection rate (DDR), were calculated. Also, the success rates of therapeutic interventions were evaluated with biopsy confirmation. RESULTS: All patients completed the study and the success rates of cecal and terminal ileal intubation were 100% with the FUSE colonoscope; we found 313 polyps in 142 patients and 173 adenomas in 95. The overall PDR, ADR and DDR were 54.2%, 36.3%, and 25.2%, respectively, and were higher in males, and increased with age. The endoscopists and nurses involved considered that the full-spectrum colonoscope improved navigation and orientation within the colon. No colonoscopy was aborted because of colonoscope malfunction. CONCLUSION: The FUSE colonoscopy yielded a higher PDR, ADR, DDR than did traditional colonoscopy, without therapeutic failure or complications, showing feasible, effective, and safe in this first Korean trial. PMID:26937150

  19. Computer-Aided Diagnostic System For Mass Survey Chest Images

    NASA Astrophysics Data System (ADS)

    Yasuda, Yoshizumi; Kinoshita, Yasuhiro; Emori, Yasufumi; Yoshimura, Hitoshi

    1988-06-01

    In order to support screening of chest radiographs on mass survey, a computer-aided diagnostic system that automatically detects abnormality of candidate images using a digital image analysis technique has been developed. Extracting boundary lines of lung fields and examining their shapes allowed various kind of abnormalities to be detected. Correction and expansion were facilitated by describing the system control, image analysis control and judgement of abnormality in the rule type programing language. In the experiments using typical samples of student's radiograms, good results were obtained for the detection of abnormal shape of lung field, cardiac hypertrophy and scoliosis. As for the detection of diaphragmatic abnormality, relatively good results were obtained but further improvements will be necessary.

  20. Assessing colonoscopic inspection skill using a virtual withdrawal simulation: a preliminary validation of performance metrics.

    PubMed

    Zupanc, Christine M; Wallis, Guy M; Hill, Andrew; Burgess-Limerick, Robin; Riek, Stephan; Plooy, Annaliese M; Horswill, Mark S; Watson, Marcus O; de Visser, Hans; Conlan, David; Hewett, David G

    2017-07-12

    The effectiveness of colonoscopy for diagnosing and preventing colon cancer is largely dependent on the ability of endoscopists to fully inspect the colonic mucosa, which they achieve primarily through skilled manipulation of the colonoscope during withdrawal. Performance assessment during live procedures is problematic. However, a virtual withdrawal simulation can help identify and parameterise actions linked to successful inspection, and offer standardised assessments for trainees. Eleven experienced endoscopists and 18 endoscopy novices (medical students) completed a mucosal inspection task during three simulated colonoscopic withdrawals. The two groups were compared on 10 performance metrics to preliminarily assess the validity of these measures to describe inspection quality. Four metrics were related to aspects of polyp detection: percentage of polyp markers found; number of polyp markers found per minute; percentage of the mucosal surface illuminated by the colonoscope (≥0.5 s); and percentage of polyp markers illuminated (≥2.5 s) but not identified. A further six metrics described the movement of the colonoscope: withdrawal time; linear distance travelled by the colonoscope tip; total distance travelled by the colonoscope tip; and distance travelled by the colonoscope tip due to movement of the up/down angulation control, movement of the left/right angulation control, and axial shaft rotation. Statistically significant experienced-novice differences were found for 8 of the 10 performance metrics (p's < .005). Compared with novices, experienced endoscopists inspected more of the mucosa and detected more polyp markers, at a faster rate. Despite completing the withdrawals more quickly than the novices, the experienced endoscopists also moved the colonoscope more in terms of linear distance travelled and overall tip movement, with greater use of both the up/down angulation control and axial shaft rotation. However, the groups did not differ in the number of polyp markers visible on the monitor but not identified, or movement of the left/right angulation control. All metrics that yielded significant group differences had adequate to excellent internal consistency reliability (α = .79 to .90). These systematic differences confirm the potential of the simulated withdrawal task for evaluating inspection skills and strategies. It may be useful for training, and assessment of trainee competence.

  1. Human nasal polyp microenvironments maintained in a viable and functional state as xenografts in NOD-scid IL2rgamma(null) mice.

    PubMed

    Bernstein, Joel M; Brooks, Stephen P; Lehman, Heather K; Pope, Liza; Sands, Amy; Shultz, Leonard D; Bankert, Richard B

    2009-12-01

    The objective was to develop a model with which to study the cellular and molecular events associated with nasal polyp progression. To accomplish this, we undertook to develop a system in which nondisrupted human nasal polyp tissue could be successfully implanted into severely immunocompromised mice, in which the histopathology of the original nasal polyp tissue, including inflammatory lymphocytes, epithelial and goblet cell hyperplasia, and subepithelial fibrosis, could be preserved for prolonged periods. Small, non-disrupted pieces of human nasal polyp tissues were subcutaneously implanted into NOD-scid IL2rgamma(null) mice. Xenografts at 8 to 12 weeks after implantation were examined histologically and immunohistochemically to identify human inflammatory leukocytes and to determine whether the characteristic histopathologic characteristics of the nasal polyps were maintained for a prolonged period. The xenografts, spleen, lung, liver, and kidneys were examined histologically and immunohistochemically and were evaluated for changes in volume. The sera of these mice were assayed for human cytokines and immunoglobulin. Xenografts of human nasal polyp tissues were established after their subcutaneous implantation into NOD-scid IL2rgamma(null) mice. The xenografts were maintained in a viable and functional state for up to 3 months, and retained a histopathologic appearance similar to that of the original tissue, with a noticeable increase in goblet cell hyperplasia and marked mucus accumulation in the submucosal glands compared to the original nasal polyp tissue. Inflammatory lymphocytes present in the polyp microenvironment were predominantly human CD8+ T cells with an effector memory phenotype. Human CD4+ T cells, CD138+ plasma cells, and CD68+ macrophages were also observed in the xenografts. Human immunoglobulin and interferon-gamma were detected in the sera of xenograft-bearing mice. The polyp-associated lymphocytes proliferated and were found to migrate from the xenografts to the spleens of the recipient mice, resulting in a significant splenomegaly. A progressive increase in the volume of the xenografts was observed with little or no evidence of mouse cell infiltration into the human leukocyte antigen-positive human tissue. An average twofold increase in polyp volume was found at 3 months after engraftment. The use of innate and adaptive immunodeficient NOD-scid mice homozygous for targeted mutations in the interleukin-2 receptor gamma-chain locus NOD-scid IL2rgamma(null) for establishing xenografts of nondisrupted pieces of human nasal polyp tissues represents a significant improvement over the previously reported xenograft model that used partially immunoincompetent CB17-scid mice as tissue recipients. The absence of the interleukin-2 receptor gamma-chain results in complete elimination of natural killer cell development, as well as severe impairments in T and B cell development. These mice, lacking both innate and adaptive immune responses, significantly improve upon the long-term engraftment of human nasal polyp tissues and provide a model with which to study how nasal polyp-associated lymphocytes and their secreted biologically active products contribute to the histopathology and progression of this chronic inflammatory disease.

  2. Foveolar gastric metaplasia of the duodenum: a frequent, so far neglected type of duodenal polyp.

    PubMed

    Sarbia, M; Sauer, G; Karimi, D; Berndt, R

    2014-04-01

    Foveolar gastric metaplasia of the duodenum (FGM) is considered as imperfect mucosal healing in the context of H. pylori gastritis and intake of NSAIDs or ASS.  Typical endoscopic findings are redness of the mucosa, erosion/ulcer and loss of mucosal folds. During diagnostic histological examinations we observed a frequent so far not described association of FGM with endoscopically observed duodenal polyps. The archives of two institutes of pathology with high gastroenterological workload (approximately 100 000 patients per year) were investigated for an association between "duodenal polyp" and "foveolar gastric metaplasia". In Institute 1, of 481 duodenal polyps 41 % were classified as FGM, 9 % as adenoma and 2 % as heterotopic gastric mucosa. In 48 % no histological correlate was present. In Institute 2, 217 cases of FGM were diagnosed. Of these, in 69 cases the endoscopic finding was "polyp" (32 %). In the other cases, the endoscopic findings were mucosal defect (18 %), redness/inflammation (16 %), suspicion for gastric heterotopia (5 %) and scar (3 %). In 26 % of cases no pathologic endoscopic finding was reported. Both groups of patients with FGM showed a similar distribution of age ranges (24 - 83 years and 16 - 88 years), median age (62 years and 61 years, respectively) and a dominance of male sex (both 1.5:1). In conclusion, foveolar gastric metaplasia is a frequent, so far neglected correlate of endoscopically detected duodenal polyps. © Georg Thieme Verlag KG Stuttgart · New York.

  3. Conjugated bile acids in gallbladder bile and serum as potential biomarkers for cholesterol polyps and adenomatous polyps.

    PubMed

    Zhao, Mei-Fen; Huang, Peng; Ge, Chun-Lin; Sun, Tao; Ma, Zhi-Gang; Ye, Fei-Fei

    2016-02-28

    To identify conjugated bile acids in gallbladder bile and serum as possible biomarkers for cholesterol polyps (CPs) and adenomatous polyps (APs). Gallbladder bile samples and serum samples were collected from 18 patients with CPs (CP group), 9 patients with APs (AP group), and 20 patients with gallstones (control group) from March to November, 2013. High performance liquid chromatography (HPLC) assay with ultraviolent detection was used to detect the concentration of 8 conjugated bile acids (glycocholic acid, GCA; taurocholic acid, TCA; glycochenodeoxycholic acid, GCDCA; taurochenodeoxycholic acid, TCDCA; glycodeoxycholic acid, GDCA; taurodeoxycholic acid, TDCA; taurolithocholic acid, TLCA; tauroursodeoxycholic acid, TUDCA) in bile samples and serum samples. The diagnostic efficacy of serum GCA, GCDCA and TCDCA was evaluated. These 8 conjugated bile acids in gallbladder bile and serum were completely identified within 10 minutes with good linearity (correlation coefficient: R>0.9900; linearity range: 3.91-500 µg/mL). Among these conjugated bile acids, the levels of gallbladder bile GCDCA and TCDCA in the CP group were significantly higher than those in the AP group (p<0.05). Furthermore, serum GCDCA and TCDCA as well as GCA were significantly higher in the AP group than the CP group (p<0.05). Serum GCDCA alone (≤12 µg/mL) had relatively better diagnostic efficacy than the other conjugated bile acids. The levels of serum GCA, GCDCA and TCDCA may be valuable for differentiation of APs and CPs.

  4. Evaluation of MTANNs for eliminating false-positive with different computer aided pulmonary nodules detection software.

    PubMed

    Shi, Zhenghao; Ma, Jiejue; Feng, Yaning; He, Lifeng; Suzuki, Kenji

    2015-11-01

    MTANN (Massive Training Artificial Neural Network) is a promising tool, which applied to eliminate false-positive for thoracic CT in recent years. In order to evaluate whether this method is feasible to eliminate false-positive of different CAD schemes, especially, when it is applied to commercial CAD software, this paper evaluate the performance of the method for eliminating false-positives produced by three different versions of commercial CAD software for lung nodules detection in chest radiographs. Experimental results demonstrate that the approach is useful in reducing FPs for different computer aided lung nodules detection software in chest radiographs.

  5. Development of a Computer-Aided Diagnosis System for Early Detection of Masses Using Retrospectively Detected Cancers on Prior Mammograms

    DTIC Science & Technology

    2007-06-01

    the masses were identified by an experi- enced Mammography Quality Standards Act (MQSA) radiologist. The no-mass data set contained 98 cases. The time...force, and the difference in time between the two acquisitions would cause differ- ences in the subtlety of the masses on the FFDMs and SFMs. However...images," Medical Physics 18, 955-963 (1991). 20A. J. Mendez, P. G. Tahoces, M. J. Lado , M. Souto, and J. J. Vidal, "Computer-aided diagnosis: Automatic

  6. DETECTION OF SMALL LESIONS OF THE LARGE BOWEL—Barium Enema Versus Double Contrast

    PubMed Central

    Robinson, J. Maurice

    1954-01-01

    Roentgen study with the so-called opaque barium enema with some modifications is superior to double contrast study as the primary means of demonstrating polyps in the colon as well as other lesions. The method described combines fluoroscopy, high kilovoltage radiography, fluoroscopically aimed “spot films” taken with compression, suction and evacuation studies. In this way unsuspected as well as suspected polyps can be demonstrated, particularly if attention is directed to the region where polyps are most likely to be found—namely, the distal third of the large bowel. Double contrast study is quite valuable as a supplement to the modified “single contrast” barium enema, but it has not been sufficiently perfected to replace the modified opaque barium enema as a primary procedure. In many instances a combination of methods will, of course, be required. PMID:13209360

  7. Pyloric gland adenoma of gallbladder—reports of two cases and a brief review of literature

    PubMed Central

    Yang, Guang; Qin, Haixia; Raza, Anwar; Saukel, George W.; Solomon, Naveenraj; Michelotti, Marcos

    2016-01-01

    Adenomas of the gallbladder are uncommon benign epithelial neoplasms. Rarely, they can give rise to gallbladder cancer, which is the most common malignancy of the biliary tract, carrying a poor prognosis and decreased survival. Here we report the case histories of two patients, 40-year-old and 53-year-old males who presented with >1 cm gallbladder polyps, which were detected and confirmed using various imaging studies. Cholecystectomy was performed on both patients and the subsequent pathologic exam revealed 1.2 and 1.6 cm polyps in the lumen. Histopathologically, both polyps showed features reminiscent of “pyloric” gland type of adenoma. The differences between the two cases in regard to histopathological and immunohistochemical characteristics will be discussed. We will also briefly review the latest nomenclature on such low-grade polypoid gallbladder entities. PMID:27034818

  8. The clinical impact of serrated colorectal polyps

    PubMed Central

    O’Connell, Brendon M; Crockett, Seth D

    2017-01-01

    Serrated polyps (SPs) of the colorectum pose a novel challenge to practicing gastroenterologists. Previously thought benign and unimportant, there is now compelling evidence that SPs are responsible for a significant percentage of incident colorectal cancer worldwide. In contrast to conventional adenomas, which tend to be slow growing and polypoid, SPs have unique features that undermine current screening and surveillance practices. For example, sessile serrated polyps (SSPs) are flat, predominately right-sided, and thought to have the potential for rapid growth. Moreover, SSPs are subject to wide variations in endoscopic detection and pathologic interpretation. Unfortunately, little is known about the natural history of SPs, and current guidelines are based largely on expert opinion. In this review, we outline the current taxonomy, epidemiology, and management of SPs with an emphasis on the clinical and public health impact of these lesions. PMID:28260946

  9. [Accuracy of computer aided measurement for detecting dental proximal caries lesions in images of cone-beam computed tomography].

    PubMed

    Zhang, Z L; Li, J P; Li, G; Ma, X C

    2017-02-09

    Objective: To establish and validate a computer program used to aid the detection of dental proximal caries in the images cone beam computed tomography (CBCT) images. Methods: According to the characteristics of caries lesions in X-ray images, a computer aided detection program for proximal caries was established with Matlab and Visual C++. The whole process for caries lesion detection included image import and preprocessing, measuring average gray value of air area, choosing region of interest and calculating gray value, defining the caries areas. The program was used to examine 90 proximal surfaces from 45 extracted human teeth collected from Peking University School and Hospital of Stomatology. The teeth were then scanned with a CBCT scanner (Promax 3D). The proximal surfaces of the teeth were respectively detected by caries detection program and scored by human observer for the extent of lesions with 6-level-scale. With histologic examination serving as the reference standard, the caries detection program and the human observer performances were assessed with receiver operating characteristic (ROC) curves. Student t -test was used to analyze the areas under the ROC curves (AUC) for the differences between caries detection program and human observer. Spearman correlation coefficient was used to analyze the detection accuracy of caries depth. Results: For the diagnosis of proximal caries in CBCT images, the AUC values of human observers and caries detection program were 0.632 and 0.703, respectively. There was a statistically significant difference between the AUC values ( P= 0.023). The correlation between program performance and gold standard (correlation coefficient r (s)=0.525) was higher than that of observer performance and gold standard ( r (s)=0.457) and there was a statistically significant difference between the correlation coefficients ( P= 0.000). Conclusions: The program that automatically detects dental proximal caries lesions could improve the diagnostic value of CBCT images.

  10. US characteristics for the prediction of neoplasm in gallbladder polyps 10 mm or larger.

    PubMed

    Kim, Jin Sil; Lee, Jeong Kyong; Kim, Yookyung; Lee, Sang Min

    2016-04-01

    To evaluate the characteristics of gallbladder polyps 10 mm or larger to predict a neoplasm in US examinations. Fifty-three patients with gallbladder polyps ≥ 10 mm with follow-up images or pathologic diagnosis were included in the retrospective study. All images and reports were reviewed to determine the imaging characteristics of gallbladder polyps. Univariate and multivariate analyses were used to evaluate predictors for a neoplastic polyp. A neoplastic polyp was verified in 12 of 53 patients and the mean size was 13.9 mm. The univariate analysis revealed that adjacent gallbladder wall thickening, larger size (≥15 mm), older age (≥57 years), absence of hyperechoic foci in a polyp, CT visibility, sessile shape, a solitary polyp, and an irregular surface were significant predictors for a neoplastic polyp. In the multivariate analysis, larger size (≥15 mm) was a significant predictor for a neoplastic polyp. A polyp size ≥15 mm was the strongest predictor for a neoplastic polyp with US. The hyperechoic foci in a polyp and CT visibility would be useful indicators for the differentiation of a neoplastic polyp, in addition to the established predictors. • A polyp size ≥15 mm is the strongest predictor for a neoplastic polyp with US. • Hyperechoic foci in a polyp and CT visibility are new predictors. • The rate of malignancy is low in polyps even 10 mm or larger (15.1 %).

  11. Estimation of the Adenoma Detection Rate From the Polyp Detection Rate by Using a Conversion Factor in a Predominantly Hispanic Population.

    PubMed

    Elhanafi, Sherif; Ortiz, Arleen M; Yarlagadda, Anita; Tsai, Cindy; Eloliby, Mohamed; Mallawaarachchi, Indika; Dwivedi, Alok; Zuckerman, Marc J; Othman, Mohamed O

    2015-08-01

    Calculating the adenoma detection rate (ADR) is a complex process in contrast to the polyp detection rate (PDR) that can be easily calculated. The average adenoma to polyp detection rate quotient (APDRQ) was proposed as a conversion factor to estimate the ADR for individual endoscopists from the endoscopist's PDR. However, this conversion factor was not validated in different practice settings. To validate the use of the proposed conversion factor in a practice setting with a predominantly Hispanic population. We conducted a retrospective, cross-sectional study (December 2007 to November 2012) of screening colonoscopies at a university practice setting with an 86.9% Hispanic population. The actual ADR and PDR were calculated for all endoscopists. The weighted average of ADR to PDR ratio for each endoscopist was used to obtain APDRQ. The APDRQ was used as a conversion multiplier to estimate each endoscopist's ADR using the single endoscopist's PDR. A total of 2148 screening colonoscopies were included. The average PDR for the whole group was 36.9% (range, 11% to 49%). The actual ADR was estimated as 25.5% (range, 11% to 37%). The average APDRQ for our group was 0.68. The estimated ADR was 25.48% (range, 8% to 33%). There was a high correlation between actual ADR and the estimated ADR (Pearson correlation=0.92). In a practice setting with a predominantly Hispanic population, a conversion factor can be used to estimate ADR from PDR providing a high degree of correlation with the actual ADR.

  12. Review of a series of proctosigmoidoscopies done at Wallops Station, Virginia

    NASA Technical Reports Server (NTRS)

    White, E.

    1969-01-01

    Routine proctosigmoidoscopic examinations for incidence of polyps in NASA installation asymptomatic personnel establish the value of this method in detecting cancer without invasion beyond the stalk and resulting in curative operation at greater survival rates than in later detections.

  13. CT differentiation of 1-2-cm gallbladder polyps: benign vs malignant.

    PubMed

    Song, E Rang; Chung, Woo-Suk; Jang, Hye Young; Yoon, Minjae; Cha, Eun Jung

    2014-04-01

    To evaluate MDCT findings of 1-2-cm sized gallbladder (GB) polyps for differentiation between benign and malignant polyps. Institutional review board approval was obtained, and informed consent was waived. Portal venous phase CT scans of 1-2-cm sized GB polyps caused by various pathologic conditions were retrospectively reviewed by two blinded observers. Among the 36 patients identified, 21 had benign polyps with the remaining 15 having malignant polyps. Size, margin, and shape of GB polyps were evaluated. Attenuation values of the polyps, including mean attenuation, maximum attenuation, and standard deviation, were recorded. As determined by visual inspection, the degree of polyp enhancement was evaluated. Using these CT findings, each of the two radiologists assessed and recorded individual diagnostic confidence for differentiating benign versus malignant polyps on a 5-point scale. The diagnostic performance of CT was evaluated using a receiver operating characteristic curve analysis. There was no significant difference in size between benign and malignant GB polyps. Ill-defined margin and sessile morphology were significantly associated with malignant polyp. There was a significant difference in mean and maximum attenuation values between benign and malignant GB polyps. Mean standard deviation value of malignant polyps was significantly higher than that of benign polyps. All malignant polyps showed either hyperenhancement or marked hyperenhancement. A z value for the diagnosis of malignant GB polyps was 0.905. Margin, shape, and enhancement degree are helpful in differentiating between benign and malignant polyps of 1-2-cm sizes.

  14. Clinical significance of peripheral circulating tumor cell counts in colorectal polyps and non-metastatic colorectal cancer.

    PubMed

    Yang, Chengguang; Zhuang, Wenfang; Hu, Yuemei; Zhu, Leiming

    2018-01-22

    The presence of peripheral circulating tumor cells indicates the possible existence of a tumor in vivo; however, low numbers of circulating tumor cells (CTCs) can be detected in peripheral blood of healthy individuals as well as patients with benign tumors. It is not known whether peripheral CTC counts differ between patients with benign colorectal disease and those with colorectal cancer. Comparative analysis of preoperative peripheral circulating tumor cells counts was completed in patients with benign colorectal disease (colorectal polyps) and non-metastatic cancer of the colon and rectum. The results of this analysis showed that patients with colorectal cancer had higher CTC counts than patients with colorectal polyps (3.47 ± 0.32/3.2 ml vs 1.49 ± 0.2/3.2 ml, P < 0.001). Colorectal cancer patients with tumors of the sigmoid colon displayed the highest CTC counts (4.87 ± 0.95/3.2 ml), followed by those with tumors of the rectum (3.73 ± 0.54/3.2 ml), ascending colon (3.5 ± 0.63/3.2 ml), transverse colon (2.4 ± 0.68/3.2 ml), and descending colon (2.08 ± 0.46/3.2 ml). Colorectal polyp patients with polyps in the rectum showed the highest CTC counts (2.2 ± 0.77/3.2 ml), followed by those with polyps in the ascending colon (1.82 ± 0.54/3.2 ml), sigmoid colon (1.38 ± 0.25/3.2 ml), transverse colon (0.75 ± 0.25/3.2 ml), and descending colon (0.33 ± 0.21/3.2 ml). The differences in CTC counts suggest that anatomical location of colorectal tumors may affect blood vessel metastasis. Meanwhile, patients with moderately differentiated and poorly differentiated tumors displayed higher peripheral blood CTC counts compared to those with well-differentiated tumors (P < 0.001). This result suggests that the type of tissue differentiation of colorectal tumors may act as another factor that affects blood vessel metastasis. Circulating tumor cells can be detected in the peripheral blood of colorectal cancer patients as well as patients with colorectal polyps. The differences in CTC counts suggest that anatomical location and the type of tissue differentiation of colorectal tumors may affect blood vessel metastasis.

  15. Comparative performance analysis for computer aided lung nodule detection and segmentation on ultra-low-dose vs. standard-dose CT

    NASA Astrophysics Data System (ADS)

    Wiemker, Rafael; Rogalla, Patrik; Opfer, Roland; Ekin, Ahmet; Romano, Valentina; Bülow, Thomas

    2006-03-01

    The performance of computer aided lung nodule detection (CAD) and computer aided nodule volumetry is compared between standard-dose (70-100 mAs) and ultra-low-dose CT images (5-10 mAs). A direct quantitative performance comparison was possible, since for each patient both an ultra-low-dose and a standard-dose CT scan were acquired within the same examination session. The data sets were recorded with a multi-slice CT scanner at the Charite university hospital Berlin with 1 mm slice thickness. Our computer aided nodule detection and segmentation algorithms were deployed on both ultra-low-dose and standard-dose CT data without any dose-specific fine-tuning or preprocessing. As a reference standard 292 nodules from 20 patients were visually identified, each nodule both in ultra-low-dose and standard-dose data sets. The CAD performance was analyzed by virtue of multiple FROC curves for different lower thresholds of the nodule diameter. For nodules with a volume-equivalent diameter equal or larger than 4 mm (149 nodules pairs), we observed a detection rate of 88% at a median false positive rate of 2 per patient in standard-dose images, and 86% detection rate in ultra-low-dose images, also at 2 FPs per patient. Including even smaller nodules equal or larger than 2 mm (272 nodules pairs), we observed a detection rate of 86% in standard-dose images, and 84% detection rate in ultra-low-dose images, both at a rate of 5 FPs per patient. Moreover, we observed a correlation of 94% between the volume-equivalent nodule diameter as automatically measured on ultra-low-dose versus on standard-dose images, indicating that ultra-low-dose CT is also feasible for growth-rate assessment in follow-up examinations. The comparable performance of lung nodule CAD in ultra-low-dose and standard-dose images is of particular interest with respect to lung cancer screening of asymptomatic patients.

  16. Evaluating Imaging and Computer-aided Detection and Diagnosis Devices at the FDA

    PubMed Central

    Gallas, Brandon D.; Chan, Heang-Ping; D’Orsi, Carl J.; Dodd, Lori E.; Giger, Maryellen L.; Gur, David; Krupinski, Elizabeth A.; Metz, Charles E.; Myers, Kyle J.; Obuchowski, Nancy A.; Sahiner, Berkman; Toledano, Alicia Y.; Zuley, Margarita L.

    2017-01-01

    This report summarizes the Joint FDA-MIPS Workshop on Methods for the Evaluation of Imaging and Computer-Assist Devices. The purpose of the workshop was to gather information on the current state of the science and facilitate consensus development on statistical methods and study designs for the evaluation of imaging devices to support US Food and Drug Administration submissions. Additionally, participants expected to identify gaps in knowledge and unmet needs that should be addressed in future research. This summary is intended to document the topics that were discussed at the meeting and disseminate the lessons that have been learned through past studies of imaging and computer-aided detection and diagnosis device performance. PMID:22306064

  17. Referring patients to nurses: Outcomes and evaluation of a nurse flexible sigmoidoscopy training program for colorectal cancer screening

    PubMed Central

    Dobrow, Mark J; Cooper, Mary Anne; Gayman, Karen; Pennington, Jason; Matthews, Joanne; Rabeneck, Linda

    2007-01-01

    Colorectal cancer is a significant health burden. Several screening options exist that can detect colorectal cancer at an early stage, leading to a more favourable prognosis. However, despite years of knowledge on best practice, screening rates are still very low in Canada, particularly in Ontario. The present paper reports on efforts to increase the flexible sigmoidoscopy screening capacity in Ontario by training nurses to perform this traditionally physician-performed procedure. Drawing on American, British and local experience, a professional regulatory framework was established, and training curriculum and assessment criteria were developed. Training was initiated at Princess Margaret Hospital and Sunnybrook and Women’s College Health Sciences Centre in Toronto, Ontario. (During the study, Sunnybrook and Women’s College Health Sciences Centre was deamalgamated into two separate hospitals: Women’s College Hospital and Sunnybrook Health Sciences Centre.) Six registered nurses participated in didactic, simulator and practical training. These nurses performed a total of 77 procedures in patients, 23 of whom had polyps detected and biopsied. Eight patients were advised to undergo colonoscopy because they had one or more neoplastic polyps. To date, six of these eight patients have undergone colonoscopy, one patient has moved out of the province and another patient is awaiting the procedure. Classifying the six patients according to the most advanced polyp histology, one patient had a negative colonoscopy (no polyps found), one patient’s polyps were hyperplastic, one had a tubular adenoma, two had advanced neoplasia (tubulovillous adenomas) and one had adenocarcinoma. All these lesions were excised completely at colonoscopy. Overall, many difficulties were anticipated and addressed in the development of the training program; ultimately, the project was affected most directly by challenges in encouraging family physicians to refer patients to the program. As health human resource strategies continue to evolve, it is believed that lessons learned from experience make an important contribution to the knowledge of how nontraditional health services can be organized and delivered. PMID:17505566

  18. [Polyps of the gallbladder].

    PubMed

    Oestmann, A

    2012-04-25

    Gallbladder polyps are a common incidental finding in ultrasound. They may be clinically significant, because adenomas have a malignant potential, in contrast to the benign cholesterol polyps occuring more frequently. As non-neoplastic polyps and neoplastic polyps cannot be morphologically discriminated in ultrasound, maximal diameter of a polyp has proven to be the best predictor for malignancy. Cholecystectomy is widely accepted as the treatment of choice for patients with polyps >1 cm. Patients with polyps <1 cm should have a follow-up check for a longer period of time (with the exception of very small polyps).

  19. [Diagnostic hysteroscopy indications and results in Complexo Hospitalario Universitario De Ourense].

    PubMed

    Pato-Mosquera, Mónica; Vázquez-Rodríguez, Marta; Pérez-Adán, Marta; García-García, María Jesús; Blanco-Pérez, Susana

    2013-07-01

    Diagnostic hysteroscopy is an endoscopic technique that allows the evaluation of the endocervical canal and uterine cavity. To evaluate indications, complications and referral to operative hysteroscopy. To analyze the correlation between sonographic display, hysteroscopy findings and histological diagnosis. Retrospective and descriptive study of 904 patients who underwent diagnostic hysteroscopy between January 1, 2008 and June 30, 2012. The most frequent indication was sonographic detection of endometrial polyps (75% were premenopausal and 71.2% postmenopausal). The complication rate associated with the test was 11.4%. The reduction experimented in operative hysteroscopies was from 31.2% in 2008 to 12.2% between January and June 2012. When a polyp or a myoma was detected by sonography, diagnostic hysteroscopy showed them in 64.4% y 62.5% of the cases, respectively. The correlation between hysteroscopic findings and histopathologic diagnosis was 77.7% for normal endometrium, 77.9% for polyps, 17.8% for hyperplasic appearance and 100% for carcinoma suspicion. Diagnostic hysteroscopy is a safe technique that allows small interventions avoiding operative hysteroscopies. There is a good relation between hysteroscopic visual inspection and anatomopathologic diagnosis, but biopsy should be taken except if normal endometrium is visualized.

  20. Using hydrofluoric acid for morphological investigations of Zoanthids (Cnidaria: Anthozoa): a critical assessment of methodology and necessity.

    PubMed

    Reimer, James Davis; Nakachi, Shu; Hirose, Mamiko; Hirose, Euichi; Hashiguchi, Shinji

    2010-10-01

    Zoanthids comprise an order of benthic, generally colonial cnidarians, which can usually be distinguished from other hexacorallians by embedded sand and detritus in their mesoglea to help strengthen their structure. These animals are becoming increasingly important research subjects in biochemistry and other research fields. Their inclusion of both calcium and silica results in the need for both decalcification and desilification for internal morphological examinations. Since the methodology of hydrofluoric acid (HF) desilification has rarely been documented in zoanthids, histological surveys for zoanthid taxonomy have often been abandoned and their taxonomy is often problematic. Recent investigations utilizing molecular methods have brought a clearer understanding of zoanthid diversity, but standardization of HF treatments are still needed to provide a link between molecular and more traditional techniques, and to properly examine specimens for which molecular methods may not be an option (e.g., formalin-preserved specimens, etc.). Here, we use both "straight" HF and, for the first time with zoanthids, buffered HF (BHF) treatments at different treatment lengths (1-48 h) on polyps from three different species of zoanthids for histological examination. Section conditions were judged based on the presence/absence of embedded detritus, drag marks, and tissue condition. Results show that the BHF treatment resulted in slightly better tissue conditions for all specimens, and suggest that desilification works well regardless of treatment time for species with smaller (polyp diameter <0.5 cm), less heavily encrusted polyps. Desilification of heavily encrusted Palythoa mutuki polyps were still problematic, with at least 24 h treatment needed. To aid future research, we provide guidelines for HF treatments of zoanthid specimens.

  1. A computer-aided approach to detect the fetal behavioral states using multi-sensor Magnetocardiographic recordings.

    PubMed

    Vairavan, S; Ulusar, U D; Eswaran, H; Preissl, H; Wilson, J D; Mckelvey, S S; Lowery, C L; Govindan, R B

    2016-02-01

    We propose a novel computational approach to automatically identify the fetal heart rate patterns (fHRPs), which are reflective of sleep/awake states. By combining these patterns with presence or absence of movements, a fetal behavioral state (fBS) was determined. The expert scores were used as the gold standard and objective thresholds for the detection procedure were obtained using Receiver Operating Characteristics (ROC) analysis. To assess the performance, intraclass correlation was computed between the proposed approach and the mutually agreed expert scores. The detected fHRPs were then associated to their corresponding fBS based on the fetal movement obtained from fetal magnetocardiogaphic (fMCG) signals. This approach may aid clinicians in objectively assessing the fBS and monitoring fetal wellbeing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Cloud-Based NoSQL Open Database of Pulmonary Nodules for Computer-Aided Lung Cancer Diagnosis and Reproducible Research.

    PubMed

    Ferreira Junior, José Raniery; Oliveira, Marcelo Costa; de Azevedo-Marques, Paulo Mazzoncini

    2016-12-01

    Lung cancer is the leading cause of cancer-related deaths in the world, and its main manifestation is pulmonary nodules. Detection and classification of pulmonary nodules are challenging tasks that must be done by qualified specialists, but image interpretation errors make those tasks difficult. In order to aid radiologists on those hard tasks, it is important to integrate the computer-based tools with the lesion detection, pathology diagnosis, and image interpretation processes. However, computer-aided diagnosis research faces the problem of not having enough shared medical reference data for the development, testing, and evaluation of computational methods for diagnosis. In order to minimize this problem, this paper presents a public nonrelational document-oriented cloud-based database of pulmonary nodules characterized by 3D texture attributes, identified by experienced radiologists and classified in nine different subjective characteristics by the same specialists. Our goal with the development of this database is to improve computer-aided lung cancer diagnosis and pulmonary nodule detection and classification research through the deployment of this database in a cloud Database as a Service framework. Pulmonary nodule data was provided by the Lung Image Database Consortium and Image Database Resource Initiative (LIDC-IDRI), image descriptors were acquired by a volumetric texture analysis, and database schema was developed using a document-oriented Not only Structured Query Language (NoSQL) approach. The proposed database is now with 379 exams, 838 nodules, and 8237 images, 4029 of them are CT scans and 4208 manually segmented nodules, and it is allocated in a MongoDB instance on a cloud infrastructure.

  3. True left-sided gallbladder with variations of bile duct and cholecystic vein.

    PubMed

    Ishii, Hiromichi; Noguchi, Akinori; Onishi, Mie; Takao, Koji; Maruyama, Takahiro; Taiyoh, Hiroaki; Araki, Yasunobu; Shimizu, Takeshi; Izumi, Hiroyuki; Tani, Naoki; Yamaguchi, Masahide; Yamane, Tetsuro

    2015-06-07

    A left-sided gallbladder without a right-sided round ligament, which is called a true left-sided gallbladder, is extremely rare. A 71-year-old woman was referred to our hospital due to a gallbladder polyp. Computed tomography (CT) revealed not only a gallbladder polyp but also the gallbladder located to the left of the round ligament connected to the left umbilical portion. CT portography revealed that the main portal vein diverged into the right posterior portal vein and the common trunk of the left portal vein and right anterior portal vein. CT cholangiography revealed that the infraportal bile duct of segment 2 joined the common bile duct. Laparoscopic cholecystectomy was performed for a gallbladder polyp, and the intraoperative finding showed that the cholecystic veins joined the round ligament. A true left-sided gallbladder is closely associated with several anomalies; therefore, surgeons encountering a true left-sided gallbladder should be aware of the potential for these anomalies.

  4. True left-sided gallbladder with variations of bile duct and cholecystic vein

    PubMed Central

    Ishii, Hiromichi; Noguchi, Akinori; Onishi, Mie; Takao, Koji; Maruyama, Takahiro; Taiyoh, Hiroaki; Araki, Yasunobu; Shimizu, Takeshi; Izumi, Hiroyuki; Tani, Naoki; Yamaguchi, Masahide; Yamane, Tetsuro

    2015-01-01

    A left-sided gallbladder without a right-sided round ligament, which is called a true left-sided gallbladder, is extremely rare. A 71-year-old woman was referred to our hospital due to a gallbladder polyp. Computed tomography (CT) revealed not only a gallbladder polyp but also the gallbladder located to the left of the round ligament connected to the left umbilical portion. CT portography revealed that the main portal vein diverged into the right posterior portal vein and the common trunk of the left portal vein and right anterior portal vein. CT cholangiography revealed that the infraportal bile duct of segment 2 joined the common bile duct. Laparoscopic cholecystectomy was performed for a gallbladder polyp, and the intraoperative finding showed that the cholecystic veins joined the round ligament. A true left-sided gallbladder is closely associated with several anomalies; therefore, surgeons encountering a true left-sided gallbladder should be aware of the potential for these anomalies. PMID:26074714

  5. A novel approach to malignant-benign classification of pulmonary nodules by using ensemble learning classifiers.

    PubMed

    Tartar, A; Akan, A; Kilic, N

    2014-01-01

    Computer-aided detection systems can help radiologists to detect pulmonary nodules at an early stage. In this paper, a novel Computer-Aided Diagnosis system (CAD) is proposed for the classification of pulmonary nodules as malignant and benign. The proposed CAD system using ensemble learning classifiers, provides an important support to radiologists at the diagnosis process of the disease, achieves high classification performance. The proposed approach with bagging classifier results in 94.7 %, 90.0 % and 77.8 % classification sensitivities for benign, malignant and undetermined classes (89.5 % accuracy), respectively.

  6. Gallbladder stones and gallbladder polyps associated with increased risk of colorectal adenoma in men.

    PubMed

    Liu, Yen-Ling; Wu, Jin-Shang; Yang, Yi-Ching; Lu, Feng-Hwa; Lee, Chih-Ting; Lin, Wan-Ju; Chang, Chih-Jen

    2018-04-01

    Most cases of colorectal cancer develop via an adenoma to carcinoma sequence. Gallbladder polyps share some risk factors with colorectal polyps. Little is known about the relationship between gallbladder diseases and different status of colorectal polyps by gender. This study was to investigate the association of gallbladder stones and polyps with colorectal adenomas by gender in a Taiwanese population. A total of 7066 eligible subjects who underwent a total colonoscopy as a part of health check-up between January 2001 and August 2009 were recruited. Colonoscopic findings were classified into polyp-free, non-neoplastic polyps and colorectal adenomas. Gallbladder stones and gallbladder polyps were diagnosed based on ultrasonographic findings. There was a significant difference in the status of colon polyps between subjects with and without gallbladder polyps. However, the status of colon polyps was not significantly different between subjects with or without gallbladder stones. After adjusting obesity, fasting plasma glucose, and other variables, there was a positive relationship between gallbladder polyps and colorectal adenomas (odds ratio [OR]: 1.396, 95% confidence interval [CI]: 1.115-1.747) but not non-neoplastic polyps in all subjects. In men, gallbladder polyps (OR: 1.560, 95% CI: 1.204-2.019) and gallbladder stones (OR: 1.465, 95% CI 1.081-1.984) were positively associated with colorectal adenomas. In women, neither gallbladder polyps nor gallbladder stones were significantly related to colon polyps. Both gallbladder polyps and gallbladder stones were associated with an increased risk of colorectal adenomas in men but not in women. Gender difference was significant for the association between gallbladder lesions and colorectal polyps. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  7. Polyp Removal of a Bloom Forming Jellyfish, Aurelia coerulea, in Korean Waters and Its Value Evaluation

    NASA Astrophysics Data System (ADS)

    Yoon, Wonduk; Chae, Jinho; Koh, Byoung-Seol; Han, Changhoon

    2018-04-01

    Aurelia coerulea is a bloom forming jellyfish that first appeared before 1980 in the western and southern Korean seas and which has been blamed for huge economical losses in all fields of marine activities. As a preventive measure to reduce economical losses, polyp removal was undertaken at Lake Shihwa, Lake Saemangeum, and Masan Bay, Korea. In the course of efforts during 2 years to remove polyps, polyps were surveyed, quantified, and removed. In these areas, the initial total polyp abundance was 5.04 × 109 and 46.25% of them were removed; Lake Shihwa the highest rates of removal and Lake Saemangeum the lowest. These efforts to remove polyps prevented the appearance of 1.20 × 109 medusae, corresponding to 78.28 × 106 kg. The cost of polyp removal was evaluated and compared with that of medusae removal. The ratio between the cost of polyp removal and that of medusae removal ranged between 0.78-3.14%, indicating large cost savings for polyp removal undertakings. However, the effect of polyp removal varied from positive to none, and we assumed that the cleared surface for polyp removal, quantity of removed polyp, and existence of polyps' hotspots in neighboring areas were the causes of the non-effectiveness of polyp removal undertakings.

  8. [Gallbladder polyps: how should they be treated and when?].

    PubMed

    Matos, Ana Sofia Bento de; Baptista, Hamilton Neves; Pinheiro, Carlos; Martinho, Fernando

    2010-01-01

    The objective of this study was to determine the correct therapeutic management for patients with gallbladder polyps (GPs), what type of surveillance should be employed and how to differentiate between benign and malignant polyps in addition to also to providing reassurance in cases of "cancerophobia". This was a 5-years retrospective study. The study was conducted at a Surgery Department at the Hospitais da Universidade de Coimbra. We analyzed all patients operated on at the Surgery Service II from January 2003 to December 2007 who had had a preoperative diagnosis of GP. Clinicopathological correlations were traced for all patients. The following were analyzed: demographic data, clinical presentation, principal symptoms, associated pathologies, supplementary tests and diagnoses. We studied 93 patients, 91 of whom had benign polyps and two of whom had malignant polyps. Of the 91 benign polyps, 73 (78.5%) were cholesterol polyps, 14 (15%) were hyperplastic and two (2.2%) were adenomas. Two (2.2%) patients had malignant polyps, both adenogallbladder carcinomas. The mean diameter of benign polyps was 6 mm and 40 (43%) patients had multiple lesions. The mean diameter of malignant and premalignant polyps taken together was 18.8 mm, all were single polyps and the mean age of this patient subset was 57.7 years. It was concluded that the surgical option for GPs is cholecystectomy and that this should only be undertaken in cases where there are clinical signs of GP; polyps with diameters greater than 10 mm; fast-growing polyps; sessile polyps or wide-based polyps; polyps with long pedicles; patient aged over 50; concurrent gallstones; polyps of the gallbladder infundibulum or abnormal gallbladder wall ultrasound.

  9. [Gallbladder polyps: prevalence and risk factors].

    PubMed

    Kratzer, W; Schmid, A; Akinli, A S; Thiel, R; Mason, R A; Schuler, A; Haenle, M M

    2011-01-01

    The objective of the present study was to investigate the prevalence of gallbladder polyps and possible risk factors in a random population sample of an urban population. A total of 2099 subjects (1072 women, 1027 men; aged 19 - 65 years, mean age 42.1 (SD ± 12.8 years) were prospectively examined using ultrasound, a standardized questionnaire and laboratory studies. Gallbladder polyps were identified in 6.1 % (128 / 2099) of all subjects (women: 6.1 % [63 / 1027]); men: 6.1 % [65 / 1072]). Solitary polyps were found in 52.4 % (65 / 124), two polyps in 16.1 % (20 / 124), three polyps in 6.5 % (8 / 124), several polyps in 22.6 % (28 / 124) and multiple polyps in 2.4 % (3 / 124) of subjects. The mean polyp diameter was 4.7 mm (SD ± 2.2; range 2 - 20 mm). The polyp diameter was ≤ 7 mm in 94.5 % of subjects. The polyps were described as pedunculate in 82.3 % (102 / 124). The polyps were broad-based in 11.3 % of subjects (14 / 124; men: 18 % women: 4.8 %). The polyps were homogeneously echogenic in 100 % of cases and with irregular contours in only one male subject. Multiple logistic regression failed to demonstrate an influence on the increased occurrence of gallbladder polyps for the risk factors of male sex, age, body-mass index (BMI), alcohol, nicotine or caffeine consumption or diabetes mellitus. The prevalence of gallbladder polyps reported in the present study (6.1 %) is higher than figures previously published for populations in Germany or Europe. The majority of polyps were pedunculate and solitary. A typical risk factor profile for gallbladder polyps could not be identified in the present population sample. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Digital subtraction dark-lumen MR colonography: initial experience.

    PubMed

    Ajaj, Waleed; Veit, Patrick; Kuehle, Christiane; Joekel, Michaela; Lauenstein, Thomas C; Herborn, Christoph U

    2005-06-01

    To evaluate image subtraction for the detection of colonic pathologies in a dark-lumen MR colonography exam. A total of 20 patients (12 males; 8 females; mean 51.4 years of age) underwent MR colonography after standard cleansing and a rectal water enema on a 1.5-T whole-body MR system. After suppression of peristaltic motion, native and Gd-contrast-enhanced three-dimensional T1-w gradient echo images were acquired in the coronal plane. Two radiologists analyzed the MR data sets in consensus on two separate occasions, with and without the subtracted images for lesion detection, and assessed the value of the subtracted data set on a five-point Likert scale (1=very helpful to 5=very unhelpful). All imaging results were compared with endoscopy. Without subtracted images, MR-colonography detected a total of five polyps, two inflammatory lesions, and one carcinoma in eight patients, which were all verified by endoscopy. Using subtraction, an additional polyp was found, and readout time was significantly shorter (6:41 vs. 7:39 minutes; P<0.05). In two patients, endoscopy detected a flat adenoma and a polyp (0.4 cm) that were missed in the MR exam. Sensitivity and specificity without subtraction were 0.67/1.0, and 0.76/1.0 with the subtracted images, respectively. Subtraction was assessed as helpful in all exams (mean value 1.8+/-0.5; Likert scale). We consider subtraction of native from contrast-enhanced dark-lumen MR colonography data sets as a beneficial supplement to the exam. Copyright (c) 2005 Wiley-Liss, Inc.

  11. Impact of cap-assisted colonoscopy on the learning curve and quality in colonoscopy: a randomized controlled trial.

    PubMed

    Tang, Zhouwen; Zhang, Daniel S; Thrift, Aaron P; Patel, Kalpesh K

    2018-03-01

    Colonoscopy competency assessment in trainees traditionally has been informal. Comprehensive metrics such as the Assessment of Competency in Endoscopy (ACE) tool suggest that competency thresholds are higher than assumed. Cap-assisted colonoscopy (CAC) may improve competency, but data regarding novice trainees are lacking. We compared CAC versus standard colonoscopy (SC) performed by novice trainees in a randomized controlled trial. All colonoscopies performed by 3 gastroenterology fellows without prior experience were eligible for the study. Exclusion criteria included patient age <18 or >90 years, pregnancy, prior colon resection, diverticulitis, colon obstruction, severe hematochezia, referral for EMR, or a procedure done without patient sedation. Patients were randomized to either CAC or SC in a 1:1 fashion. The primary outcome was the independent cecal intubation rate (ICIR). Secondary outcomes were cecal intubation time, polyp detection rate, polyp miss rate, adenoma detection rate, ACE tool scores, and cumulative summation learning curves. A total of 203 colonoscopies were analyzed, 101 in CAC and 102 in SC. CAC resulted in a significantly higher cecal intubation rate, at 79.2% in CAC compared with 66.7% in SC (P = .04). Overall cecal intubation time was significantly shorter at 13.7 minutes for CAC versus 16.5 minutes for SC (P =.02). Cecal intubation time in the case of successful independent fellow intubation was not significantly different between CAC and SC (11.6 minutes vs 12.7 minutes; P = .29). Overall ACE tool motor and cognitive scores were higher with CAC. Learning curves for ICIR approached the competency threshold earlier with cap use but reached competency for only 1 fellow. The polyp detection rate, polyp miss rate, and adenoma detection rate were not significantly different between groups. CAC resulted in significant improvement in ICIR, overall ACE tool scores, and trend toward competency on learning curves when compared with SC in colonoscopy trainees without prior colonoscopy experience. (Clinical trial registration number: NCT02472730.). Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  12. Dynamic MRI-based computer aided diagnostic systems for early detection of kidney transplant rejection: A survey

    NASA Astrophysics Data System (ADS)

    Mostapha, Mahmoud; Khalifa, Fahmi; Alansary, Amir; Soliman, Ahmed; Gimel'farb, Georgy; El-Baz, Ayman

    2013-10-01

    Early detection of renal transplant rejection is important to implement appropriate medical and immune therapy in patients with transplanted kidneys. In literature, a large number of computer-aided diagnostic (CAD) systems using different image modalities, such as ultrasound (US), magnetic resonance imaging (MRI), computed tomography (CT), and radionuclide imaging, have been proposed for early detection of kidney diseases. A typical CAD system for kidney diagnosis consists of a set of processing steps including: motion correction, segmentation of the kidney and/or its internal structures (e.g., cortex, medulla), construction of agent kinetic curves, functional parameter estimation, diagnosis, and assessment of the kidney status. In this paper, we survey the current state-of-the-art CAD systems that have been developed for kidney disease diagnosis using dynamic MRI. In addition, the paper addresses several challenges that researchers face in developing efficient, fast and reliable CAD systems for the early detection of kidney diseases.

  13. Computer-Aided Recognition of Facial Attributes for Fetal Alcohol Spectrum Disorders.

    PubMed

    Valentine, Matthew; Bihm, Dustin C J; Wolf, Lior; Hoyme, H Eugene; May, Philip A; Buckley, David; Kalberg, Wendy; Abdul-Rahman, Omar A

    2017-12-01

    To compare the detection of facial attributes by computer-based facial recognition software of 2-D images against standard, manual examination in fetal alcohol spectrum disorders (FASD). Participants were gathered from the Fetal Alcohol Syndrome Epidemiology Research database. Standard frontal and oblique photographs of children were obtained during a manual, in-person dysmorphology assessment. Images were submitted for facial analysis conducted by the facial dysmorphology novel analysis technology (an automated system), which assesses ratios of measurements between various facial landmarks to determine the presence of dysmorphic features. Manual blinded dysmorphology assessments were compared with those obtained via the computer-aided system. Areas under the curve values for individual receiver-operating characteristic curves revealed the computer-aided system (0.88 ± 0.02) to be comparable to the manual method (0.86 ± 0.03) in detecting patients with FASD. Interestingly, cases of alcohol-related neurodevelopmental disorder (ARND) were identified more efficiently by the computer-aided system (0.84 ± 0.07) in comparison to the manual method (0.74 ± 0.04). A facial gestalt analysis of patients with ARND also identified more generalized facial findings compared to the cardinal facial features seen in more severe forms of FASD. We found there was an increased diagnostic accuracy for ARND via our computer-aided method. As this category has been historically difficult to diagnose, we believe our experiment demonstrates that facial dysmorphology novel analysis technology can potentially improve ARND diagnosis by introducing a standardized metric for recognizing FASD-associated facial anomalies. Earlier recognition of these patients will lead to earlier intervention with improved patient outcomes. Copyright © 2017 by the American Academy of Pediatrics.

  14. Computational Electromagnetic Modeling of SansEC(Trade Mark) Sensors

    NASA Technical Reports Server (NTRS)

    Smith, Laura J.; Dudley, Kenneth L.; Szatkowski, George N.

    2011-01-01

    This paper describes the preliminary effort to apply computational design tools to aid in the development of an electromagnetic SansEC resonant sensor composite materials damage detection system. The computational methods and models employed on this research problem will evolve in complexity over time and will lead to the development of new computational methods and experimental sensor systems that demonstrate the capability to detect, diagnose, and monitor the damage of composite materials and structures on aerospace vehicles.

  15. Performance of fusion algorithms for computer-aided detection and classification of mines in very shallow water obtained from testing in navy Fleet Battle Exercise-Hotel 2000

    NASA Astrophysics Data System (ADS)

    Ciany, Charles M.; Zurawski, William; Kerfoot, Ian

    2001-10-01

    The performance of Computer Aided Detection/Computer Aided Classification (CAD/CAC) Fusion algorithms on side-scan sonar images was evaluated using data taken at the Navy's's Fleet Battle Exercise-Hotel held in Panama City, Florida, in August 2000. A 2-of-3 binary fusion algorithm is shown to provide robust performance. The algorithm accepts the classification decisions and associated contact locations form three different CAD/CAC algorithms, clusters the contacts based on Euclidian distance, and then declares a valid target when a clustered contact is declared by at least 2 of the 3 individual algorithms. This simple binary fusion provided a 96 percent probability of correct classification at a false alarm rate of 0.14 false alarms per image per side. The performance represented a 3.8:1 reduction in false alarms over the best performing single CAD/CAC algorithm, with no loss in probability of correct classification.

  16. [Factors associated with malignancy in gallbladder polyps without gallbladder stone].

    PubMed

    Lee, Jae Seung; Lee, Kyu Taek; Jung, Jae Hong; Ok, Sung Wook; Choi, Sung Chul; Lee, Kwang Hyuck; Lee, Jong Kyun; Heo, Jin Seok; Choi, Seong Ho; Rhee, Jong Chul

    2008-08-01

    The purpose of this study was to find the factors predicting the neoplastic polyp of gallbladder and analyze the size criteria associated with malignancy. A total of 354 subjects with gallbladder polyps confirmed by tissue pathology were included for the analysis. The clinical and radiological features of the polyps were compared between the two groups (neoplastic vs. non-neoplastic) and in the three groups (non-neoplastic vs. adenoma vs. adenocarcinoma). The independent factors associated with malignancy were studied. Of 354 patients, non-neoplastic polyps were observed in 229 (64.7%) patents, adenoma in 85 (24.0%) and adenocarcinoma in 40 (11.3%). The mean diameter of non-neoplastic polyp, adenoma, and adenocarcinoma were 11.3+/-2.8 mm, 16.0+/-7.2 mm, and 27.0+/-8.9 mm, respectively. The mean age of patients with non-neoplastic polyp, adenoma, and adenocarcinoma were 44.8+/-11.3, 49.9+/-12.5, and 60.8+/-9.6, respectively. Age, size of polyp, number of polyp, presence of diabetes, and presence of symptom showed statistically significant difference between the neoplastic polyp and non-neoplastic polyp groups. But only age, size of polyp, number of polyp were statistically independent factors associated with neoplastic polyp (p<0.05). To predict the neoplastic polyp, sensitivity was 94.4%, but specificity was 18.3% on the basis of 10 mm criteria. whereas sensitivity and specificity was 76.0% and 55.5% on the 12 mm-criteria. On the basis of our analysis, the size of polyp is the most important factor to predict the malignancy. In the 10 mm criteria, sensitivity is satisfactory but specificity is very low. Therefore 10 mm size should not be considered to be the absolute size-criterion for surgery.

  17. Identification of non-neoplastic and neoplastic gastric polyps using multiphoton microscopy

    NASA Astrophysics Data System (ADS)

    Jiang, Shanghai; Kang, Deyong; Xu, Meifang; Zhu, Xiaoqin; Zhuo, Shuangmu; Chen, Jianxin

    2012-12-01

    Gastric polyps can be broadly defined as luminal lesions projecting above the plane of the mucosal surface. They are generally divided into non-neoplastic and neoplastic polyps. Accurate diagnosis of neoplastic polyps is important because of their well-known relationship with gastric cancer. Multiphoton microscopy (MPM) based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) is one of the most important recent inventions in biological imaging. In this study, we used MPM to image the microstructure of gastric polyps, including fundic gland polyps, hyperplastic polyps, inflammatory fibroid polyps and adenomas, then compared with gold-standard hematoxylin- eosin(H-E)-stained histopathology. MPM images showed that different gastric polyps have different gland architecture and cell morphology. Dilated, elongated or branch-like hyperplastic polyps are arranged by columnar epithelial cells. Inflammatory fibroid polyps are composed of small, thin-walled blood vessels surrounded by short spindle cells. Fundic glands polyps are lined by parietal cells and chief cells, admixed with normal glands. Gastric adenomas are generally composed of tubules or villi of dysplastic epithelium, which usually show some degree of intestinal-type differentiation toward absorptive cells, goblet cells, endocrine cells. Our results demonstrated that MPM can be used to identify non- neoplastic and neoplastic gastric polyps without the need of any staining procedure.

  18. Comparative effectiveness of i-SCAN™ and high-definition white light characterizing small colonic polyps.

    PubMed

    Chan, Johanna L; Lin, Li; Feiler, Michael; Wolf, Andrew I; Cardona, Diana M; Gellad, Ziad F

    2012-11-07

    To evaluate accuracy of in vivo diagnosis of adenomatous vs non-adenomatous polyps using i-SCAN digital chromoendoscopy compared with high-definition white light. This is a single-center comparative effectiveness pilot study. Polyps (n = 103) from 75 average-risk adult outpatients undergoing screening or surveillance colonoscopy between December 1, 2010 and April 1, 2011 were evaluated by two participating endoscopists in an academic outpatient endoscopy center. Polyps were evaluated both with high-definition white light and with i-SCAN to make an in vivo prediction of adenomatous vs non-adenomatous pathology. We determined diagnostic characteristics of i-SCAN and high-definition white light, including sensitivity, specificity, and accuracy, with regards to identifying adenomatous vs non-adenomatous polyps. Histopathologic diagnosis was the gold standard comparison. One hundred and three small polyps, detected from forty-three patients, were included in the analysis. The average size of the polyps evaluated in the analysis was 3.7 mm (SD 1.3 mm, range 2 mm to 8 mm). Formal histopathology revealed that 54/103 (52.4%) were adenomas, 26/103 (25.2%) were hyperplastic, and 23/103 (22.3%) were other diagnoses include "lymphoid aggregates", "non-specific colitis," and "no pathologic diagnosis." Overall, the combined accuracy of endoscopists for predicting adenomas was identical between i-SCAN (71.8%, 95%CI: 62.1%-80.3%) and high-definition white light (71.8%, 95%CI: 62.1%-80.3%). However, the accuracy of each endoscopist differed substantially, where endoscopist A demonstrated 63.0% overall accuracy (95%CI: 50.9%-74.0%) as compared with endoscopist B demonstrating 93.3% overall accuracy (95%CI: 77.9%-99.2%), irrespective of imaging modality. Neither endoscopist demonstrated a significant learning effect with i-SCAN during the study. Though endoscopist A increased accuracy using i-SCAN from 59% (95%CI: 42.1%-74.4%) in the first half to 67.6% (95%CI: 49.5%-82.6%) in the second half, and endoscopist B decreased accuracy using i-SCAN from 100% (95%CI: 80.5%-100.0%) in the first half to 84.6% (95%CI: 54.6%-98.1%) in the second half, neither of these differences were statistically significant. i-SCAN and high-definition white light had similar efficacy predicting polyp histology. Endoscopist training likely plays a critical role in diagnostic test characteristics and deserves further study.

  19. The efficacy of real-time colour Doppler flow imaging on endoscopic ultrasonography for differential diagnosis between neoplastic and non-neoplastic gallbladder polyps.

    PubMed

    Kim, Su Young; Cho, Jae Hee; Kim, Eui Joo; Chung, Dong Hae; Kim, Kun Kuk; Park, Yeon Ho; Kim, Yeon Suk

    2018-05-01

    We evaluated the usefulness of real-time colour Doppler flow (CDF) endoscopic ultrasonography (EUS) for differentiating neoplastic gallbladder (GB) polyps from non-neoplastic polyps. Between August 2014 and December 2016, a total of 233 patients with GB polyps who underwent real-time CDF-EUS were consecutively enrolled in this prospective study. CDF imaging was subjectively categorized for each patient as: strong CDF pattern, weak CDF pattern and no CDF pattern. Of the 233 patients, 115 underwent surgical resection. Of these, there were 90 cases of non-neoplastic GB polyps and 23 cases of neoplastic GB polyps. In a multivariate analysis, a strong CDF pattern was the most significant predictive factor for neoplastic polyps; sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 52.2 %, 79.4 %, 38.7 %, 86.9 % and 73.9 %, respectively. Solitary polyp and polyp size were associated with an increased risk of neoplasm. The presence of a strong CDF pattern as well as solitary and larger polyps on EUS may be predictive of neoplastic GB polyps. As real-time CDF-EUS poses no danger to the patient and requires no additional equipment, it is likely to become a supplemental tool for the differential diagnosis of GB polyps. • Differential diagnosis between neoplastic polyps and non-neoplastic polyps of GB is limited. • The use of real-time CDF-EUS was convenient, with high agreement between operators. • The real-time CDF-EUS is helpful in differential diagnosis of GB polyps.

  20. Wavelet Entropy and Directed Acyclic Graph Support Vector Machine for Detection of Patients with Unilateral Hearing Loss in MRI Scanning

    PubMed Central

    Wang, Shuihua; Yang, Ming; Du, Sidan; Yang, Jiquan; Liu, Bin; Gorriz, Juan M.; Ramírez, Javier; Yuan, Ti-Fei; Zhang, Yudong

    2016-01-01

    Highlights We develop computer-aided diagnosis system for unilateral hearing loss detection in structural magnetic resonance imaging.Wavelet entropy is introduced to extract image global features from brain images. Directed acyclic graph is employed to endow support vector machine an ability to handle multi-class problems.The developed computer-aided diagnosis system achieves an overall accuracy of 95.1% for this three-class problem of differentiating left-sided and right-sided hearing loss from healthy controls. Aim: Sensorineural hearing loss (SNHL) is correlated to many neurodegenerative disease. Now more and more computer vision based methods are using to detect it in an automatic way. Materials: We have in total 49 subjects, scanned by 3.0T MRI (Siemens Medical Solutions, Erlangen, Germany). The subjects contain 14 patients with right-sided hearing loss (RHL), 15 patients with left-sided hearing loss (LHL), and 20 healthy controls (HC). Method: We treat this as a three-class classification problem: RHL, LHL, and HC. Wavelet entropy (WE) was selected from the magnetic resonance images of each subjects, and then submitted to a directed acyclic graph support vector machine (DAG-SVM). Results: The 10 repetition results of 10-fold cross validation shows 3-level decomposition will yield an overall accuracy of 95.10% for this three-class classification problem, higher than feedforward neural network, decision tree, and naive Bayesian classifier. Conclusions: This computer-aided diagnosis system is promising. We hope this study can attract more computer vision method for detecting hearing loss. PMID:27807415

  1. Wavelet Entropy and Directed Acyclic Graph Support Vector Machine for Detection of Patients with Unilateral Hearing Loss in MRI Scanning.

    PubMed

    Wang, Shuihua; Yang, Ming; Du, Sidan; Yang, Jiquan; Liu, Bin; Gorriz, Juan M; Ramírez, Javier; Yuan, Ti-Fei; Zhang, Yudong

    2016-01-01

    Highlights We develop computer-aided diagnosis system for unilateral hearing loss detection in structural magnetic resonance imaging.Wavelet entropy is introduced to extract image global features from brain images. Directed acyclic graph is employed to endow support vector machine an ability to handle multi-class problems.The developed computer-aided diagnosis system achieves an overall accuracy of 95.1% for this three-class problem of differentiating left-sided and right-sided hearing loss from healthy controls. Aim: Sensorineural hearing loss (SNHL) is correlated to many neurodegenerative disease. Now more and more computer vision based methods are using to detect it in an automatic way. Materials: We have in total 49 subjects, scanned by 3.0T MRI (Siemens Medical Solutions, Erlangen, Germany). The subjects contain 14 patients with right-sided hearing loss (RHL), 15 patients with left-sided hearing loss (LHL), and 20 healthy controls (HC). Method: We treat this as a three-class classification problem: RHL, LHL, and HC. Wavelet entropy (WE) was selected from the magnetic resonance images of each subjects, and then submitted to a directed acyclic graph support vector machine (DAG-SVM). Results: The 10 repetition results of 10-fold cross validation shows 3-level decomposition will yield an overall accuracy of 95.10% for this three-class classification problem, higher than feedforward neural network, decision tree, and naive Bayesian classifier. Conclusions: This computer-aided diagnosis system is promising. We hope this study can attract more computer vision method for detecting hearing loss.

  2. Risk stratification of gallbladder polyps larger than 10 mm using high-resolution ultrasonography and texture analysis.

    PubMed

    Choi, Tae Won; Kim, Jung Hoon; Park, Sang Joon; Ahn, Su Joa; Joo, Ijin; Han, Joon Koo

    2018-01-01

    To assess important features for risk stratification of gallbladder (GB) polyps >10 mm using high-resolution ultrasonography (HRUS) and texture analysis. We included 136 patients with GB polyps (>10 mm) who underwent both HRUS and cholecystectomy (non-neoplastic, n = 58; adenomatous, n = 32; and carcinoma, n = 46). Two radiologists retrospectively assessed HRUS findings and texture analysis. Multivariate analysis was performed to identify significant predictors for neoplastic polyps and carcinomas. Single polyp (OR, 3.680-3.856) and larger size (OR, 1.450-1.477) were independently associated with neoplastic polyps (p < 0.05). In a single or polyp >14 mm, sensitivity for differentiating neoplastic from non-neoplastic polyps was 92.3%. To differentiate carcinoma from adenoma, sessile shape (OR, 9.485-41.257), larger size (OR, 1.267-1.303), higher skewness (OR, 6.382) and lower grey-level co-occurrence matrices (GLCM) contrast (OR, 0.963) were significant predictors (p < 0.05). In a polyp >22 mm or sessile, sensitivity for differentiating carcinomas from adenomas was 93.5-95.7%. If a polyp demonstrated at least one HRUS finding and at least one texture feature, the specificity for diagnosing carcinoma was increased to 90.6-93.8%. In a GB polyp >10 mm, single and diameter >14 mm were useful for predicting neoplastic polyps. In neoplastic polyps, sessile shape, diameter >22 mm, higher skewness and lower GLCM contrast were useful for predicting carcinoma. • Risk of neoplastic polyp is low in <14 mm and multiple polyps • A sessile polyp or >22 mm has increased risk for GB carcinomas • Higher skewness and lower GLCM contrast are predictors of GB carcinoma • HRUS is useful for risk stratification of GB polyps >1 cm.

  3. Colorectal Cancer Risk Assessment Tool

    MedlinePlus

    ... 11/12/2014 Risk Calculator About the Tool Colorectal Cancer Risk Factors Download SAS and Gauss Code Page ... Rectal Cancer: Prevention, Genetics, Causes Tests to Detect Colorectal Cancer and Polyps Cancer Risk Prediction Resources Update November ...

  4. Tissue resonance interaction accurately detects colon lesions: A double-blind pilot study.

    PubMed

    Dore, Maria P; Tufano, Marcello O; Pes, Giovanni M; Cuccu, Marianna; Farina, Valentina; Manca, Alessandra; Graham, David Y

    2015-07-07

    To investigated the performance of the tissue resonance interaction method (TRIM) for the non-invasive detection of colon lesions. We performed a prospective single-center blinded pilot study of consecutive adults undergoing colonoscopy at the University Hospital in Sassari, Italy. Before patients underwent colonoscopy, they were examined by the TRIMprobe which detects differences in electromagnetic properties between pathological and normal tissues. All patients had completed the polyethylene glycol-containing bowel prep for the colonoscopy procedure before being screened. During the procedure the subjects remained fully dressed. A hand-held probe was moved over the abdomen and variations in electromagnetic signals were recorded for 3 spectral lines (462-465 MHz, 930 MHz, and 1395 MHz). A single investigator, blind to any clinical information, performed the test using the TRIMprob system. Abnormal signals were identified and recorded as malignant or benign (adenoma or hyperplastic polyps). Findings were compared with those from colonoscopy with histologic confirmation. Statistical analysis was performed by χ(2) test. A total of 305 consecutive patients fulfilling the inclusion criteria were enrolled over a period of 12 months. The most frequent indication for colonoscopy was abdominal pain (33%). The TRIMprob was well accepted by all patients; none spontaneously complained about the procedure, and no adverse effects were observed. TRIM proved inaccurate for polyp detection in patients with inflammatory bowel disease (IBD) and they were excluded leaving 281 subjects (mean age 59 ± 13 years; 107 males). The TRIM detected and accurately characterized all 12 adenocarcinomas and 135/137 polyps (98.5%) including 64 adenomatous (100%) found. The method identified cancers and polyps with 98.7% sensitivity, 96.2% specificity, and 97.5% diagnostic accuracy, compared to colonoscopy and histology analyses. The positive predictive value was 96.7% and the negative predictive value 98.4%. Among the 281 non-IBD subjects, there were 7 cases with discordant results (2.5%) between TRIMprob and the reference standard including 5 false positive results (1.8%) and 2 false negative (0.7%) results. The main limitation of the TRIMprob system is the need for trained operators. The study confirmed that TRIM provides rapid, accurate, convenient and noninvasive means to identify individuals most likely to benefit from colonoscopy.

  5. Tissue resonance interaction accurately detects colon lesions: A double-blind pilot study

    PubMed Central

    Dore, Maria P; Tufano, Marcello O; Pes, Giovanni M; Cuccu, Marianna; Farina, Valentina; Manca, Alessandra; Graham, David Y

    2015-01-01

    AIM: To investigated the performance of the tissue resonance interaction method (TRIM) for the non-invasive detection of colon lesions. METHODS: We performed a prospective single-center blinded pilot study of consecutive adults undergoing colonoscopy at the University Hospital in Sassari, Italy. Before patients underwent colonoscopy, they were examined by the TRIMprobe which detects differences in electromagnetic properties between pathological and normal tissues. All patients had completed the polyethylene glycol-containing bowel prep for the colonoscopy procedure before being screened. During the procedure the subjects remained fully dressed. A hand-held probe was moved over the abdomen and variations in electromagnetic signals were recorded for 3 spectral lines (462-465 MHz, 930 MHz, and 1395 MHz). A single investigator, blind to any clinical information, performed the test using the TRIMprob system. Abnormal signals were identified and recorded as malignant or benign (adenoma or hyperplastic polyps). Findings were compared with those from colonoscopy with histologic confirmation. Statistical analysis was performed by χ2 test. RESULTS: A total of 305 consecutive patients fulfilling the inclusion criteria were enrolled over a period of 12 months. The most frequent indication for colonoscopy was abdominal pain (33%). The TRIMprob was well accepted by all patients; none spontaneously complained about the procedure, and no adverse effects were observed. TRIM proved inaccurate for polyp detection in patients with inflammatory bowel disease (IBD) and they were excluded leaving 281 subjects (mean age 59 ± 13 years; 107 males). The TRIM detected and accurately characterized all 12 adenocarcinomas and 135/137 polyps (98.5%) including 64 adenomatous (100%) found. The method identified cancers and polyps with 98.7% sensitivity, 96.2% specificity, and 97.5% diagnostic accuracy, compared to colonoscopy and histology analyses. The positive predictive value was 96.7% and the negative predictive value 98.4%. Among the 281 non-IBD subjects, there were 7 cases with discordant results (2.5%) between TRIMprob and the reference standard including 5 false positive results (1.8%) and 2 false negative (0.7%) results. The main limitation of the TRIMprob system is the need for trained operators. CONCLUSION: The study confirmed that TRIM provides rapid, accurate, convenient and noninvasive means to identify individuals most likely to benefit from colonoscopy. PMID:26167085

  6. Is it necessary to perform prophylactic cholecystectomy for all symptomatic gallbladder polyps diagnosed with ultrasound?

    PubMed

    Velidedeoğlu, Mehmet; Çitgez, Bülent; Arıkan, Akif Enes; Ayan, Fadıl

    2017-01-01

    The main aim of this study is to determine the necessity of cholecystectomy in patients with ultrasound diagnosed symptomatic polypoid lesions of the gallbladder. The data of 82 patients with polypoid lesions of the gallbladder who had cholecystectomy between 2000 and 2012 were analyzed retrospectively with preoperative ultrasound and histopathology results. The mean age was 48.05±11.18 years (range 25-74 years). All patients underwent preoperative ultrasound examination. Eighteen (22%) of the 82 patients were asymptomatic; their polypoid lesions of the gallbladder were detected with ultrasound during a check-up or other reasons. In 45 (55%) of cases pathology reported no polypoid lesions of the gallbladder. Right upper quadrant or epigastric pain was the most common symptom (41.46%) that led to hepatobiliary ultrasound, the other symptom was dyspepsia (36.59%). On preoperative ultrasound evaluation, 22 patients had multiple polyps, and 9 of these 22 patients had at least 3 polyps. There is an inaccuracy of ultrasound to detect polypoid lesions of the gallbladder. After diagnosing polypoid lesions of the gallbladder by using standard ultrasound, further pre-operative diagnostic tests are needed to help discriminating benign lesions from malignant ones, which may prevent unnecessary surgery regardless of symptoms.

  7. Composition and abundance of microbiota in the pharynx in patients with laryngeal carcinoma and vocal cord polyps.

    PubMed

    Gong, Hongli; Wang, Boyan; Shi, Yi; Shi, Yong; Xiao, Xiyan; Cao, Pengyu; Tao, Lei; Wang, Yuezhu; Zhou, Liang

    2017-08-01

    The pharynx is an important site of microbiota colonization, but the bacterial populations at this site have been relatively unexplored by culture-independent approaches. The aim of this study was to characterize the microbiota structure of the pharynx. Pyrosequencing of 16S rRNA gene libraries was used to characterize the pharyngeal microbiota using swab samples from 68 subjects with laryngeal cancer and 28 subjects with vocal cord polyps. Overall, the major phylum was Firmicutes, with Streptococcus as the predominant genus in the pharyngeal communities. Nine core operational taxonomic units detected from Streptococcus, Fusobacterium, Prevotella, Granulicatella, and Veillonella accounted for 21.3% of the total sequences detected. However, there was no difference in bacterial communities in the pharynx from patients with laryngeal cancer and vocal cord polyps. The relative abundance of Firmicutes was inversely correlated with Fusobacteria, Proteobacteria, Actinobacteria, and Bacteroidetes. The correlation was evident at the genus level, and the relative abundance of Streptococcus was inversely associated with Fusobacterium, Leptotrichia, Neisseria, Actinomyces, and Prevotella. This study presented a profile for the overall structure of the microbiota in pharyngeal swab samples. Inverse correlations were found between Streptococcus and other bacterial communities, suggesting that potential antagonism may exist among pharyngeal microbiota.

  8. An evaluation of computer-aided disproportionality analysis for post-marketing signal detection.

    PubMed

    Lehman, H P; Chen, J; Gould, A L; Kassekert, R; Beninger, P R; Carney, R; Goldberg, M; Goss, M A; Kidos, K; Sharrar, R G; Shields, K; Sweet, A; Wiholm, B E; Honig, P K

    2007-08-01

    To understand the value of computer-aided disproportionality analysis (DA) in relation to current pharmacovigilance signal detection methods, four products were retrospectively evaluated by applying an empirical Bayes method to Merck's post-marketing safety database. Findings were compared with the prior detection of labeled post-marketing adverse events. Disproportionality ratios (empirical Bayes geometric mean lower 95% bounds for the posterior distribution (EBGM05)) were generated for product-event pairs. Overall (1993-2004 data, EBGM05> or =2, individual terms) results of signal detection using DA compared to standard methods were sensitivity, 31.1%; specificity, 95.3%; and positive predictive value, 19.9%. Using groupings of synonymous labeled terms, sensitivity improved (40.9%). More of the adverse events detected by both methods were detected earlier using DA and grouped (versus individual) terms. With 1939-2004 data, diagnostic properties were similar to those from 1993 to 2004. DA methods using Merck's safety database demonstrate sufficient sensitivity and specificity to be considered for use as an adjunct to conventional signal detection methods.

  9. Computer-Aided Detection of Mammographic Masses in Dense Breast Images

    DTIC Science & Technology

    2005-06-01

    Kinnard, Ph.D. CONTRACTING ORGANIZATION: Howard University Washington, DC 20059 REPORT DATE: June 2005 TYPE OF REPORT: Annual Summary PREPARED FOR: U.S...AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Howard University Washington, DC 20059 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES...34, Preparing for the Postdoctoral Institute, August, 2004, Howard University and The University of Texas at El Paso. 2. "Computer-Aided Diagnosis and Image

  10. Evaluating success of curettage in the surgical treatment of endometrial polyps.

    PubMed

    Hafizi, Leili; Mousavifar, Nezhat; Zirak, Nahid; Khadem, Nayereh; Davarpanah, Sousan; Akhondi, Mohsen

    2015-02-01

    To determine treatment efficacy of curettage on endometrial polyp. The quasi-experimental pre-and-post study was conducted in 2011-12 at the gynaecology department of Imam Reza Hospital, Mashhad, Iran, and comprised patients who underwent hysteroscopy for endometrial polyp. Location, size, number and base condition of the polyps were recorded before the patient underwent curettage. Hysteroscopy was then performed and the condition of the remaining polyps was compared with initial findings. Also, the remaining polyps were resected. SPSS 13 was used for statistical analysis. There were 51 patients in the study with a mean age of 33.14 ± 8.19 years (range: 23-59 years)Besides, there were 82 polyps; 38(46.3%) having a narrow base, and 44(53.7%) having a wide base. The mean polyp size was 2.39 ± 2.63cm.After performing curettage, 23 (28.0%) polyps were removed completely, 39(47.6%) had size reduction, and 20(24.4%) had no change in size. Curettage could not significantly remove polyps (p < 0.001). Polyps smaller than 2cm were more likely to have been removed compared to the bigger ones (p = 0.003).Polyps with wide base were more significantly removed than those with narrow base (p < 0.001).Further, those with wide base and also smaller than 2 cm were removed more significantly than others (p < 0.001).The location of polyps had no effect on removal probability by curettage (p = 0.114). Curettage was not found to be a reliable method for endometrial polyp removal. If hysteroscopy is not accessible, the size of the polyp should be determined by vaginal sonograghy to estimate the probability of its removal by curettage.

  11. Correlation of morphological and molecular parameters for colon cancer

    NASA Astrophysics Data System (ADS)

    Yuan, Shuai; Roney, Celeste A.; Li, Qian; Jiang, James; Cable, Alex; Summers, Ronald M.; Chen, Yu

    2010-02-01

    Colorectal cancer (CRC) is the second leading cause of cancer death in the United States. There is great interest in studying the relationship among microstructures and molecular processes of colorectal cancer during its progression at early stages. In this study, we use our multi-modality optical system that could obtain co-registered optical coherence tomography (OCT) and fluorescence molecular imaging (FMI) images simultaneously to study CRC. The overexpressed carbohydrate α-L-fucose on the surfaces of polyps facilitates the bond of adenomatous polyps with UEA-1 and is used as biomarker. Tissue scattering coefficient derived from OCT axial scan is used as quantitative value of structural information. Both structural images from OCT and molecular images show spatial heterogeneity of tumors. Correlations between those values are analyzed and demonstrate that scattering coefficients are positively correlated with FMI signals in conjugated. In UEA-1 conjugated samples (8 polyps and 8 control regions), the correlation coefficient is ranged from 0.45 to 0.99. These findings indicate that the microstructure of polyps is changed gradually during cancer progression and the change is well correlated with certain molecular process. Our study demonstrated that multi-parametric imaging is able to simultaneously detect morphology and molecular information and it can enable spatially and temporally correlated studies of structure-function relationships during tumor progression.

  12. Computer-aided diagnosis of leukoencephalopathy in children treated for acute lymphoblastic leukemia

    NASA Astrophysics Data System (ADS)

    Glass, John O.; Li, Chin-Shang; Helton, Kathleen J.; Reddick, Wilburn E.

    2005-04-01

    The purpose of this study was to use objective quantitative MR imaging methods to develop a computer-aided diagnosis tool to differentiate white matter (WM) hyperintensities as either leukoencephalopathy (LE) or normal maturational processes in children treated for acute lymphoblastic leukemia with intravenous high dose methotrexate. A combined imaging set consisting of T1, T2, PD, and FLAIR MR images and WM, gray matter, and cerebrospinal fluid a priori maps from a spatially normalized atlas were analyzed with a neural network segmentation based on a Kohonen Self-Organizing Map. Segmented regions were manually classified to identify the most hyperintense WM region and the normal appearing genu region. Signal intensity differences normalized to the genu within each examination were generated for two time points in 203 children. An unsupervised hierarchical clustering algorithm with the agglomeration method of McQuitty was used to divide data from the first examination into normal appearing or LE groups. A C-support vector machine (C-SVM) was then trained on the first examination data and used to classify the data from the second examination. The overall accuracy of the computer-aided detection tool was 83.5% (299/358) with sensitivity to normal WM of 86.9% (199/229) and specificity to LE of 77.5% (100/129) when compared to the readings of two expert observers. These results suggest that subtle therapy-induced leukoencephalopathy can be objectively and reproducibly detected in children treated for cancer using this computer-aided detection approach based on relative differences in quantitative signal intensity measures normalized within each examination.

  13. Sessile Serrated Adenomas: How to Detect, Characterize and Resect

    PubMed Central

    Ma, Michael X.; Bourke, Michael J.

    2017-01-01

    Serrated polyps are important contributors to the burden of colorectal cancers (CRC). These lesions were once considered to have no malignant potential, but currently up to 30% of all CRC are recognized to arise from the serrated neoplasia pathway. The primary premalignant lesions are sessile serrated adenomas/polyps (SSA/Ps), although traditional serrated adenomas are relatively uncommon. Compared to conventional adenomas, SSA/Ps are morphologically subtle with indistinct borders, may be difficult to detect endoscopically, are more prevalent than previously thought, are associated with synchronous and metachronous advanced neoplasia, and have a higher risk of incomplete resection. Although many lesions remain “dormant,” progressive disease is associated with the development of dysplasia and more rapid progression to CRC. As a result, SSA/Ps are strongly implicated in the development of interval cancers. These factors represent unique challenges that require a meticulous approach to their management. In this review, we summarize the contemporary literature on the characterization, detection and resection of SSA/Ps. PMID:28494577

  14. An analysis-by-synthesis approach to the estimation of vocal cord polyp features.

    PubMed

    Koizumi, T; Taniguchi, S; Itakura, F

    1993-09-01

    This paper deals with a new noninvasive method of estimating vocal cord polyp features through hoarse-voice analysis. A noteworthy feature of this method is that it enables us not only to discriminate hoarse voices caused by pathological vocal cords with a single golf-ball-like polyp from normal voices, but also to estimate polyp features such as the mass and dimension of polyp through the use of a novel model of pathological vocal cords which has been devised to simulate the subtle movement of the vocal cords. A synthetic hoarse voice produced with a hoarse-voice synthesizer is compared with a natural hoarse voice caused by the vocal cord polyp in terms of a distance measure and the polyp features are estimated by minimizing the distance measure. Some estimates of polyp dimension that have been obtained by applying this procedure to hoarse voices are found to compare favorably with actual polyp dimensions, demonstrating that the procedure is effective for estimating the features of golf-ball-like vocal cord polyps.

  15. [Clinical and endoscopic features of a selected population with serrated colorectal adenomas in a private clinic in Lima - Peru].

    PubMed

    Castillo, Ofelia; Barreda, Carlos; Recavarren, Sixto; Barriga, José A; Salazar M, Fernando; Yriberry, Simón; Barriga, Eduardo; Salazar C, Fernando

    2013-01-01

    To describe the clinical and endoscopic caracteristics of a population that has only serrated polyps of colon (mainly sessile serrated adenomas) in a private clinic in Lima, Perú, from 2009-2011. Retrospective study conducted at the endoscopy center of Clinic Ricardo Palma, Lima, Peru. Olympus colonoscope was used with high definition, including NBI (narrow band imaging) and electronic magnification. Patients had pathologic diagnosis of “polyps and / or colorectal serrated adenomas” and excluded those with synchronous tubular or villous adenomas. Images were evaluated by two endoscopists and then by a third gastroenterologist. We found 201 serrated polyps in 108 patients. Women were 60.2% and overweight predominated. Eighty (74.1%) had only one serrated adenoma and 23 (21.3%) with at least one synchronous hyperplastic polyp. The average size of sessile serrated adenomas was 5.12 mm (± 3.87 DS) and the flat type was 91 (58.7%). There were significant differences in the diameter of sessile serrated adenomas between the distal and proximal colon (4.47 mm ± 2.23 vs. 6.90 mm ± 6.25; p<0.000). The common features of sessile serrated adenomas were: White (31/36, 86.1%), smooth (28/36, 77.8%) and regular margins (26/36, 72.2%). There was a relationship between vascular pattern according NBI and serrated polyp histology (p=0.024). The endoscopic features of sessile serrated adenomas can evade detection to white light. NBI is a useful tool to define some features of these lesions.

  16. Natural history of small gallbladder polyps is benign: evidence from a clinical and pathogenetic study.

    PubMed

    Colecchia, Antonio; Larocca, Anna; Scaioli, Eleonora; Bacchi-Reggiani, Maria Letizia; Di Biase, Anna Rita; Azzaroli, Francesco; Gualandi, Roberta; Simoni, Patrizia; Vestito, Amanda; Festi, Davide

    2009-03-01

    Little is known about the natural history and pathogenesis of small gallbladder polyps (<10 mm, usually of the cholesterol type), particularly in Western populations. It is unclear if these polyps and gallstones represent different aspects of the same disease. The aim of this study was to characterize the natural history and pathogenesis of small gallbladder polyps. Fifty-six Caucasian patients with small gallbladder polyps, 30 matched gallstone patients, and 30 controls were enrolled in this 5-year prospective study. Patients underwent a symptomatic questionnaire, abdominal ultrasonography, and ultrasonographic evaluation of gallbladder motility at baseline and yearly intervals for 5 years. Cholesterol saturation index, cholesterol crystals in bile, and apolipoprotein E genotype were also determined. Most patients with polyps (mean size: 5.3 mm) were men (61%), asymptomatic, and had multiple polyps (57%). Polyps did not change in 91% of patients during follow-up. No subject experienced biliary pain or underwent cholecystectomy; four developed gallstones. Cholesterol saturation index was higher in patients with polyps or gallstones than in controls (P<0.05). Cholesterol crystals were more frequent in patients with polyps than in controls (P<0.0001) but less common than in gallstone patients (P<0.0001). Polyps and gallstones were associated with nonapolipoprotein E4 phenotypes. The natural history of small gallbladder polyps was benign, as no patient developed specific symptoms and/or morphological changes in polyps. Consequently, a "wait and see" policy is advisable in these patients. Polyps have some pathogenetic mechanisms in common with gallstones, but few patients developed gallstones.

  17. Photoacoustic Imaging for Differential Diagnosis of Benign Polyps versus Malignant Polyps of the Gallbladder: A Preliminary Study.

    PubMed

    Chae, Hee-Dong; Lee, Jae Young; Jang, Jin-Young; Chang, Jin Ho; Kang, Jeeun; Kang, Mee Joo; Han, Joon Koo

    2017-01-01

    To investigate the feasibility of ex vivo multispectral photoacoustic (PA) imaging in differentiating cholesterol versus neoplastic polyps, and benign versus malignant polyps, of the gallbladder. A total of 38 surgically confirmed gallbladder polyps (24 cholesterol polyps, 4 adenomas, and 10 adenocarcinomas) from 38 patients were prospectively included in this study. The surgical specimens were set on a gel pad immersed in a saline-filled container. The PA intensities of polyps were then measured, using two separate wavelength intervals (421-647 nm and 692-917 nm). Mann-Whitney U test was performed for the comparison of normalized PA intensities between the cholesterol and neoplastic polyps, and between the benign and malignant polyps. Kruskal-Wallis test was conducted for the comparison of normalized PA intensities among the cholesterol polyps, adenomas, and adenocarcinomas. A significant difference was observed in the normalized PA intensities between the cholesterol and neoplastic polyps at 459 nm (median, 1.00 vs. 0.73; p = 0.032). Comparing the benign and malignant polyps, there were significant differences in the normalized PA intensities at 765 nm (median, 0.67 vs. 0.78; p = 0.013), 787 nm (median, 0.65 vs. 0.77; p = 0.034), and 853 nm (median, 0.59 vs. 0.85; p = 0.028). The comparison of the normalized PA intensities among cholesterol polyps, adenomas, and adenocarcinomas demonstrated marginally significant differences at 765 nm (median, 0.67 vs. 0.66 vs. 0.78, respectively; p = 0.049). These preliminary results indicate that benign versus malignant gallbladder polyps might exhibit different spectral patterns on multispectral PA imaging.

  18. Distinct antimicrobial peptide expression determines host species-specific bacterial associations

    PubMed Central

    Franzenburg, Sören; Walter, Jonas; Künzel, Sven; Wang, Jun; Baines, John F.; Bosch, Thomas C. G.; Fraune, Sebastian

    2013-01-01

    Animals are colonized by coevolved bacterial communities, which contribute to the host’s health. This commensal microbiota is often highly specific to its host-species, inferring strong selective pressures on the associated microbes. Several factors, including diet, mucus composition, and the immune system have been proposed as putative determinants of host-associated bacterial communities. Here we report that species-specific antimicrobial peptides account for different bacterial communities associated with closely related species of the cnidarian Hydra. Gene family extensions for potent antimicrobial peptides, the arminins, were detected in four Hydra species, with each species possessing a unique composition and expression profile of arminins. For functional analysis, we inoculated arminin-deficient and control polyps with bacterial consortia characteristic for different Hydra species and compared their selective preferences by 454 pyrosequencing of the bacterial microbiota. In contrast to control polyps, arminin-deficient polyps displayed decreased potential to select for bacterial communities resembling their native microbiota. This finding indicates that species-specific antimicrobial peptides shape species-specific bacterial associations. PMID:24003149

  19. Tests to Detect Colorectal Cancer and Polyps

    MedlinePlus

    ... colonoscopy. People are usually not sedated for this test. Studies have shown that people who have regular screening ... patients receive some form of sedation during the test. Studies suggest that colonoscopy reduces deaths from colorectal cancer ...

  20. Simplified computer-aided detection scheme of microcalcification clusters in digital breast tomosynthesis images.

    PubMed

    Ji-Wook Jeong; Seung-Hoon Chae; Eun Young Chae; Hak Hee Kim; Young Wook Choi; Sooyeul Lee

    2016-08-01

    A computer-aided detection (CADe) algorithm for clustered microcalcifications (MCs) in reconstructed digital breast tomosynthesis (DBT) images is suggested. The MC-like objects were enhanced by a Hessian-based 3D calcification response function, and a signal-to-noise ratio (SNR) enhanced image was also generated to screen the MC clustering seed objects. A connected component segmentation method was used to detect the cluster seed objects, which were considered as potential clustering centers of MCs. Bounding cubes for the accepted clustering seed candidate were generated and the overlapping cubes were combined and examined. After the MC clustering and false-positive (FP) reduction step, the average number of FPs was estimated to be 0.87 per DBT volume with a sensitivity of 90.5%.

  1. [Gallbladder polyps: Clinical and pathological features in Cholecystectomy patients in the Anglo American clinic in the period of 1999-2007].

    PubMed

    Bugosen Tannous, Munira; Tagle Arróspide, Martín; Huerta-Mercado Tenorio, Jorge; Scavino Levy, Yolanda

    2011-01-01

    To describe the clinical and anatomopathologic characteristics of gallbladder polyps found in patients who underwent cholecystectomy at Clinica Anglo Americana for the 1999-2007 period. Descriptive and retrospective study that started at Pathology Department where patients with anatomopathologic finding of gallbladder polyps who underwent cholecystectomy for the 1999-2007 period were selected. Clinical records were reviewed to take ultrasonographic, anatomopathologic and clinical characteristics, which were included and studied in a data base in Microsoft Excel. Gallbladder polyps were found in 172 (10%) of 1707 gallbladders that were analized. Cholesterolosic polyps were found in 95.4% of the cases, 4% were adenomas and 0.6% were hyperplasic polyps. Gallbladder polyps ≥ 10 mm were found in 32,25% of the cases. A 90% of these polyps were cholesterolosic and a 10% were adenomas. No malign polyps were found in this study. The vast majority of gallbladder polyps, including the ≥ 10 mm group, were cholesterolosic. The physician decision to remove the gallbladder must be individualized and discussed with each patient, considering gallbladder polyp characteristics such as size and growth rate of the lesion.

  2. Histologic characteristics of gastric polyps in Korea: Emphasis on discrepancy between endoscopic forceps biopsy and endoscopic mucosal resection specimen

    PubMed Central

    Yoon, Won Jae; Lee, Dong Ho; Jung, Yong Jin; Jeong, Ji Bong; Kim, Ji Won; Kim, Byeong Gwan; Lee, Kook Lae; Lee, Kwang Hyuck; Park, Young Soo; Hwang, Jin-Hyeok; Kim, Jin-Wook; Kim, Nayoung; Lee, Jun Kyu; Jung, Hyun Chae; Yoon, Yong Bum; Song, In Sung

    2006-01-01

    AIM: To investigate histological characteristics of gastric polyps in the Korean population. METHODS: We reviewed endoscopic photographs and medical records of patients with gastric polyps who underwent endoscopic mucosal resection from April 1996 through February 2003. RESULTS: A total of 85 gastric polyps from 74 patients were reviewed. Male-to-female ratio was 1:1.96. Mean age was 59.9 ± 10.8 years. Multiple polyps were observed in 10.8%. Gastric polyps occurred most frequently in the antrum (58.8%). Pathological results on resected specimens were as follows: tubular adenoma 45.9%, hyperplastic polyp 31.8%, inflammatory polyp 9.4%, hamartoma 3.5%, fundic gland polyp 2.4%, tubulovillous adenoma 2.4%, adenocarcinoma 2.4%, dysplasia 1.1%, and mucosal pseudolipomatosis 1.1%. Discrepancy rate between endoscopic biopsy and pathology of resected specimens was 27.1%. There was no relationship between the size of the polyp and concordance rate. CONCLUSION: There is considerable discrepancy in histologic findings between endoscopic forceps biopsy and resected specimens. Approaches to review of the histology of an entire polyp should be performed, especially when an adenoma is suspected. PMID:16810753

  3. [Gallbladder polyps: correlation between ultrasonographic and histopathological findings].

    PubMed

    Escalona, Alex; León, Francisca; Bellolio, Felipe; Pimentel, Fernando; Guajardo, Matías; Gennero, Rubén; Cruz, Juan Pablo; Viviani, Paola; Ibáñez, Luis

    2006-10-01

    Gallbladder polyps are becoming a common finding. The management of these polyps is complicated considering that they can bear malignant lesions. To analyze the ultrasonographic and histopathologic findings of patients operated due to gallbladder polyps. The records of patients with ultrasonographic diagnosis of gallbladder polyp and that underwent cholecystectomy in a thirteen years period were reviewed, collecting their demographic, ultrasonographic and histopathological data. One hundred and twenty three patients were operated. The mean age was 44+/-13 years, and 69% were women. The mean size of polyps in ultrasonography was 7.3+/-5 mm. Histopathology confirmed the presence of polyps in 79% of patients, with a mean size and number of lesions of 5.1+/-3.8 mm and 2.1+/-2, respectively. Nine percent of polyps were greater than 10 mm, and single polyps were significantly larger than the multiple ones (p =0.003). Four cases of adenoma (3.2%) were diagnosed; one of them had in situ carcinoma. All were single and larger than 10 mm. We found a significant correlation between ultrasonographic and histopathological polyp size determination (r =0.47; p =0.002). Polyp size was also a predictor of the presence of adenoma (p =0.043; confidence intervals: 1.006-1.424). There is a good correlation between the size of the gallbladder polyp in ultrasonography and the size in the histopathology report. Gallbladder adenoma is uncommon and it correlates with the size of the polyp. In this series, size was the only predictor of the presence of adenoma.

  4. Hypoechoic foci on EUS are simple and strong predictive factors for neoplastic gallbladder polyps.

    PubMed

    Cho, Jae Hee; Park, Jeong Youp; Kim, Yoon Jae; Kim, Hee Man; Kim, Hong Jeong; Hong, Sung Pil; Park, Seung Woo; Chung, Jae Bock; Song, Si Young; Bang, Seungmin

    2009-06-01

    EUS is an accurate imaging modality for delineating gallbladder (GB) structures; however, its clinical use in differentiating neoplastic GB polyps from nonneoplastic polyps is limited. Thus, we sought to characterize neoplastic GB polyps by analyzing unique EUS features. Our analysis revealed variably shaped, relatively hypoechoic portions in the core of polyps compared with general background echogenicity. Our purpose was to make a differential diagnosis between neoplastic and nonneoplastic GB polyps of less than 20 mm by use of EUS variables, including hypoechoic foci. Retrospective single-center study. University teaching hospital. Patients (n = 88) underwent preoperative EUS and cholecystectomy for GB polyps smaller than 20 mm. Hypoechoic foci were found in 30 of 33 patients (91%) with neoplastic polyps and 6 of 55 (11%) with nonneoplastic polyps. In a multivariate analysis, hypoechoic foci were the only significant predictive factor for neoplastic polyps (odds ratio [OR] 55.4, 95% CI, 8.26-371, P < .001); the sensitivity and specificity were 90% and 89%, respectively. In addition, polyps >15 mm had an increased risk of malignancy (OR 21.7, 95% CI, 2.35-201, P = .007), as did those with hypoechoic foci (OR 10.9; 95% CI, 1.01-117, P = .049). Retrospective review of selected patients from a tertiary medical center. The presence of hypoechoic foci on EUS is a strong predictive factor for neoplastic polyps. EUS may be useful in developing a treatment strategy for GB polyps.

  5. PDGFRA-mutant syndrome.

    PubMed

    Ricci, Riccardo; Martini, Maurizio; Cenci, Tonia; Carbone, Arnaldo; Lanza, Paola; Biondi, Alberto; Rindi, Guido; Cassano, Alessandra; Larghi, Alberto; Persiani, Roberto; Larocca, Luigi M

    2015-07-01

    Germline PDGFRA mutations cause multiple heterogeneous gastrointestinal mesenchymal tumors. In its familial form this disease, which was formerly termed intestinal neurofibromatosis/neurofibromatosis 3b (INF/NF3b), has been included among familial gastrointestinal stromal tumors (GISTs) because of its genotype, described when GIST was the only known PDGFRA-mutant gastrointestinal tumor. Shortly afterwards, however, inflammatory fibroid polyps also revealed PDGFRA mutations. Subsequently, gastrointestinal CD34+ 'fibrous tumors' of uncertain classification were described in a germline PDGFRA-mutant context. Our aim was to characterize the syndrome produced by germline PDGFRA mutations and establish diagnostic criteria and management strategies for this hitherto puzzling disease. We studied a kindred displaying multiple gastrointestinal mesenchymal tumors, comparing it with published families/individuals with possible analogous conditions. We identified a novel inherited PDGFRA mutation (P653L), constituting the third reported example of familial PDGFRA mutation. In adult mutants we detected inflammatory fibroid polyps, gastric GISTs and gastrointestinal fibrous tumors of uncertain nosology. We demonstrate that the syndrome formerly defined as INF/NF3b (exemplified by the family reported herein) is simplistically considered a form of familial GIST, because inflammatory fibroid polyps often prevail. Fibrous tumors appear variants of inflammatory fibroid polyps. 'INF/NF3b' and 'familial GIST' are misleading terms which we propose changing to 'PDGFRA-mutant syndrome'. In this condition, unlike KIT-dependent familial GIST syndromes, if present, GISTs are stomach-restricted and diffuse Cajal cell hyperplasia is not observed. This restriction of GISTs to the stomach in PDGFRA-mutant syndrome: (i) focuses oncological concern on gastric masses, as inflammatory fibroid polyps are benign; (ii) supports a selective role of gastric environment for PDGFRA mutations to elicit GISTs, justifying the known predilection for stomach of sporadic PDGFRA-mutant GISTs. An awareness that inflammatory fibroid polyps, relatively common among gastrointestinal mesenchymal tumors, may be the prevailing tumor in PDGFRA-mutant syndrome could eventually reveal an unsuspected prevalence of this condition.

  6. Is cholecystectomy a reasonable treatment option for simple gallbladder polyps larger than 10 mm?

    PubMed

    Park, Hye Yon; Oh, Se Hoon; Lee, Kwang Hyuck; Lee, Jong Kyun; Lee, Kyu Taek

    2015-04-14

    To determine the relevance of the 10-mm size criterion of the generally accepted surgical indication for gallbladder polyps (GBPs). We collected data of patients who were confirmed to have GBPs through cholecystectomy at Samsung Medical Center between January 1997 and December 2012. Among the patients who underwent cholecystectomy for GBP, those with a definite evidence for malignancy such as adjacent organ invasion, metastasis on preoperative imaging studies, polyp larger than 20 mm, absence of preoperative imaging study results, and patients having gallstones were excluded. We retrospectively collected and analyzed information on patient's clinical characteristics, symptoms, ultrasonographic findings, and blood laboratory tests. A total of 836 patients who had undergone cholecystectomy were retrospectively analyzed. Seven hundred eighty patients (93%) had benign polyps, whereas 56 patients (7%) had malignant polyps. Of the 56 patients with malignancy, 4 patients (7%) had borderline GBP (10-12 mm) and a patient had small GBP (< 10 mm) with T2 stage. We conducted an ROC curve analysis to verify the 10-mm size criteria (AUC = 0.887, SD = 0.21, P < 0.001). In the ROC curve for polyp size and malignancy, sensitivity and specificity of the 10-mm size criterion was 98.2% and 19.6%, respectively. The specificity of the 11-mm and 12-mm size criteria was 44.6% and 56%, respectively, whereas the sensitivity of these two size criteria was similar. We defined the GBPs of 10 to 12 mm as a borderline-sized GBP, which were found in 411 patients (49%). In this group, there was a significant difference in age between patients with benign and malignant GBPs (47 years vs 60 years, P < 0.05). GBPs larger than 13 mm need immediate excision whereas for borderline-sized GBPs detected in young patients, careful medical observation can be a rational decision.

  7. Is cholecystectomy a reasonable treatment option for simple gallbladder polyps larger than 10 mm?

    PubMed Central

    Park, Hye Yon; Oh, Se Hoon; Lee, Kwang Hyuck; Lee, Jong Kyun; Lee, Kyu Taek

    2015-01-01

    AIM: To determine the relevance of the 10-mm size criterion of the generally accepted surgical indication for gallbladder polyps (GBPs). METHODS: We collected data of patients who were confirmed to have GBPs through cholecystectomy at Samsung Medical Center between January 1997 and December 2012. Among the patients who underwent cholecystectomy for GBP, those with a definite evidence for malignancy such as adjacent organ invasion, metastasis on preoperative imaging studies, polyp larger than 20 mm, absence of preoperative imaging study results, and patients having gallstones were excluded. We retrospectively collected and analyzed information on patient’s clinical characteristics, symptoms, ultrasonographic findings, and blood laboratory tests. RESULTS: A total of 836 patients who had undergone cholecystectomy were retrospectively analyzed. Seven hundred eighty patients (93%) had benign polyps, whereas 56 patients (7%) had malignant polyps. Of the 56 patients with malignancy, 4 patients (7%) had borderline GBP (10-12 mm) and a patient had small GBP (< 10 mm) with T2 stage. We conducted an ROC curve analysis to verify the 10-mm size criteria (AUC = 0.887, SD = 0.21, P < 0.001). In the ROC curve for polyp size and malignancy, sensitivity and specificity of the 10-mm size criterion was 98.2% and 19.6%, respectively. The specificity of the 11-mm and 12-mm size criteria was 44.6% and 56%, respectively, whereas the sensitivity of these two size criteria was similar. We defined the GBPs of 10 to 12 mm as a borderline-sized GBP, which were found in 411 patients (49%). In this group, there was a significant difference in age between patients with benign and malignant GBPs (47 years vs 60 years, P < 0.05). CONCLUSION: GBPs larger than 13 mm need immediate excision whereas for borderline-sized GBPs detected in young patients, careful medical observation can be a rational decision. PMID:25892875

  8. [Expression and role of IL-18 in chronic rhinosinusitis].

    PubMed

    Liu, R W; Du, J T; Liu, Y F; Liu, S X

    2018-04-01

    Objective: To study the expression and role of interleukin-18 (IL-18) in different clinical phenotypes of chronic rhinosinusitis(CRS)and in different subtypes of CRS with nasal polyps (CRSwNP). Method: During nasal endoscopic surgery, inferior turbinates were obtained from 13 patients with nasal septum deviation (control group),uncinate processes were obtained from 10 patients with chronic rhinosinusitis without nasal polyps (CRSsNP) and nasal polyp tissues were obtained from 36 patients with CRSwNP, respectively. IL-5 expression in CRSwNP was detected by ELISA, and the expression of IL-18 mRNA and protein in different subtypes of CRS were assessed by real-time PCR, ELISA and immunohistochemistr. Result: CRSwNP was divided into 12 cases of IL-5 positive nasal polyps (IL-5+NP)group and 24 cases of IL-5 negative nasal polyps (IL-5-NP)group. The expression of IL-18 mRNA and protein in all CRSsNP,IL-5+NP and IL-5-NP groups were higher than that in control group ( P <0.01 or P <0.05),but no significant difference existed between IL-5+NP and IL-5-NP ( P >0.05) group. IL-18 also expresses in epithelial cells of normal nasal mucosa. Conclusion: CRSwNP can be divided into two main subtypes: IL-5+NP and IL-5-NP. The increasing expression of IL-18 in CRSsNP, IL-5+NP and IL-5-NP compared with control group indicates that IL-18 may play a key role in the pathogenesis of CRS, and IL-18 expression in nasal polyps is not affected by the type of inflammation. The possible presence of balance between IL-18 and IL-18 binding protein in normal nasal mucosa provides a new way for research and treatment of CRS. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

  9. Effectiveness of computer-aided diagnosis of colorectal lesions using novel software for magnifying narrow-band imaging: a pilot study.

    PubMed

    Tamai, Naoto; Saito, Yutaka; Sakamoto, Taku; Nakajima, Takeshi; Matsuda, Takahisa; Sumiyama, Kazuki; Tajiri, Hisao; Koyama, Ryosuke; Kido, Shoji

    2017-08-01

     Magnifying narrow-band imaging (M-NBI) enables detailed observation of microvascular architecture and can be used in endoscopic diagnosis of colorectal lesion. However, in clinical practice, differential diagnosis and estimation of invasion depth of colorectal lesions based on M-NBI findings require experience. Therefore, developing computer-aided diagnosis (CAD) for M-NBI would be beneficial for clinical practice. The aim of this study was to evaluate the effectiveness of software for CAD of colorectal lesions. In collaboration with Yamaguchi University, we developed novel software that enables CAD of colorectal lesions using M-NBI images. This software for CAD further specifically divides original Sano's colorectal M-NBI classification into 3 groups (group A, capillary pattern [CP] type I; group B, CP type II + CP type IIIA; group C, CP type IIIB), which describe hyperplastic polyps (HPs), adenoma/adenocarcinoma (intramucosal [IM] to submucosal [SM]-superficial) lesions, and SM-deep lesions, respectively. We retrospectively reviewed 121 lesions evaluated using M-NBI. The 121 reviewed lesions included 21 HP, 80 adenoma/adenocarcinoma (IM to SM-superficial), and 20 SM-deep lesions. The concordance rate between the CAD and the diagnosis of the experienced endoscopists was 90.9 %. The sensitivity, specificity, positive and negative predictive values, and accuracy of the CAD for neoplastic lesions were 83.9 %, 82.6 %, 53.1 %, 95.6 %, and 82.8 %, respectively. The values for SM-deep lesions were 83.9 %, 82.6 %, 53.1 %, 95.6 %, and 82.8 %, respectively.  Relatively high diagnostic values were obtained using CAD. This software for CAD could possibly lead to a wider use of M-NBI in the endoscopic diagnosis of colorectal lesions.

  10. Hypomethylation of DNA from Benign and Malignant Human Colon Neoplasms

    NASA Astrophysics Data System (ADS)

    Goelz, Susan E.; Vogelstein, Bert; Hamilton, Stanley R.; Feinberg, Andrew P.

    1985-04-01

    The methylation state of DNA from human colon tissue displaying neoplastic growth was determined by means of restriction endonuclease analysis. When compared to DNA from adjacent normal tissue, DNA from both benign colon polyps and malignant carcinomas was substantially hypomethylated. With the use of probes for growth hormone, γ -globin, α -chorionic gonadotropin, and γ -crystallin, methylation changes were detected in all 23 neoplastic growths examined. Benign polyps were hypomethylated to a degree similar to that in malignant tissue. These results indicate that hypomethylation is a consistent biochemical characteristic of human colonic tumors and is an alteration in the DNA that precedes malignancy.

  11. Multitarget stool DNA testing for colorectal-cancer screening.

    PubMed

    Imperiale, Thomas F; Ransohoff, David F; Itzkowitz, Steven H; Levin, Theodore R; Lavin, Philip; Lidgard, Graham P; Ahlquist, David A; Berger, Barry M

    2014-04-03

    An accurate, noninvasive test could improve the effectiveness of colorectal-cancer screening. We compared a noninvasive, multitarget stool DNA test with a fecal immunochemical test (FIT) in persons at average risk for colorectal cancer. The DNA test includes quantitative molecular assays for KRAS mutations, aberrant NDRG4 and BMP3 methylation, and β-actin, plus a hemoglobin immunoassay. Results were generated with the use of a logistic-regression algorithm, with values of 183 or more considered to be positive. FIT values of more than 100 ng of hemoglobin per milliliter of buffer were considered to be positive. Tests were processed independently of colonoscopic findings. Of the 9989 participants who could be evaluated, 65 (0.7%) had colorectal cancer and 757 (7.6%) had advanced precancerous lesions (advanced adenomas or sessile serrated polyps measuring ≥1 cm in the greatest dimension) on colonoscopy. The sensitivity for detecting colorectal cancer was 92.3% with DNA testing and 73.8% with FIT (P=0.002). The sensitivity for detecting advanced precancerous lesions was 42.4% with DNA testing and 23.8% with FIT (P<0.001). The rate of detection of polyps with high-grade dysplasia was 69.2% with DNA testing and 46.2% with FIT (P=0.004); the rates of detection of serrated sessile polyps measuring 1 cm or more were 42.4% and 5.1%, respectively (P<0.001). Specificities with DNA testing and FIT were 86.6% and 94.9%, respectively, among participants with nonadvanced or negative findings (P<0.001) and 89.8% and 96.4%, respectively, among those with negative results on colonoscopy (P<0.001). The numbers of persons who would need to be screened to detect one cancer were 154 with colonoscopy, 166 with DNA testing, and 208 with FIT. In asymptomatic persons at average risk for colorectal cancer, multitarget stool DNA testing detected significantly more cancers than did FIT but had more false positive results. (Funded by Exact Sciences; ClinicalTrials.gov number, NCT01397747.).

  12. Computer-aided detection of pulmonary embolism at CT pulmonary angiography: can it improve performance of inexperienced readers?

    PubMed

    Blackmon, Kevin N; Florin, Charles; Bogoni, Luca; McCain, Joshua W; Koonce, James D; Lee, Heon; Bastarrika, Gorka; Thilo, Christian; Costello, Philip; Salganicoff, Marcos; Joseph Schoepf, U

    2011-06-01

    To evaluate the effect of a computer-aided detection (CAD) algorithm on the performance of novice readers for detection of pulmonary embolism (PE) at CT pulmonary angiography (CTPA). We included CTPA examinations of 79 patients (50 female, 52 ± 18 years). Studies were evaluated by two independent inexperienced readers who marked all vessels containing PE. After 3 months all studies were reevaluated by the same two readers, this time aided by CAD prototype. A consensus read by three expert radiologists served as the reference standard. Statistical analysis used χ(2) and McNemar testing. Expert consensus revealed 119 PEs in 32 studies. For PE detection, the sensitivity of CAD alone was 78%. Inexperienced readers' initial interpretations had an average per-PE sensitivity of 50%, which improved to 71% (p < 0.001) with CAD as a second reader. False positives increased from 0.18 to 0.25 per study (p = 0.03). Per-study, the readers initially detected 27/32 positive studies (84%); with CAD this number increased to 29.5 studies (92%; p = 0.125). Our results suggest that CAD significantly improves the sensitivity of PE detection for inexperienced readers with a small but appreciable increase in the rate of false positives.

  13. Segmentation and detection of breast cancer in mammograms combining wavelet analysis and genetic algorithm.

    PubMed

    Pereira, Danilo Cesar; Ramos, Rodrigo Pereira; do Nascimento, Marcelo Zanchetta

    2014-04-01

    In Brazil, the National Cancer Institute (INCA) reports more than 50,000 new cases of the disease, with risk of 51 cases per 100,000 women. Radiographic images obtained from mammography equipments are one of the most frequently used techniques for helping in early diagnosis. Due to factors related to cost and professional experience, in the last two decades computer systems to support detection (Computer-Aided Detection - CADe) and diagnosis (Computer-Aided Diagnosis - CADx) have been developed in order to assist experts in detection of abnormalities in their initial stages. Despite the large number of researches on CADe and CADx systems, there is still a need for improved computerized methods. Nowadays, there is a growing concern with the sensitivity and reliability of abnormalities diagnosis in both views of breast mammographic images, namely cranio-caudal (CC) and medio-lateral oblique (MLO). This paper presents a set of computational tools to aid segmentation and detection of mammograms that contained mass or masses in CC and MLO views. An artifact removal algorithm is first implemented followed by an image denoising and gray-level enhancement method based on wavelet transform and Wiener filter. Finally, a method for detection and segmentation of masses using multiple thresholding, wavelet transform and genetic algorithm is employed in mammograms which were randomly selected from the Digital Database for Screening Mammography (DDSM). The developed computer method was quantitatively evaluated using the area overlap metric (AOM). The mean ± standard deviation value of AOM for the proposed method was 79.2 ± 8%. The experiments demonstrate that the proposed method has a strong potential to be used as the basis for mammogram mass segmentation in CC and MLO views. Another important aspect is that the method overcomes the limitation of analyzing only CC and MLO views. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Differences in detection rates of adenomas and serrated polyps in screening versus surveillance colonoscopies, based on the new hampshire colonoscopy registry.

    PubMed

    Anderson, Joseph C; Butterly, Lynn F; Goodrich, Martha; Robinson, Christina M; Weiss, Julia E

    2013-10-01

    The adenoma detection rate (ADR) is an important quality indicator originally developed for screening colonoscopies. However, it is unclear whether the ADR should be calculated using data from screening and surveillance examinations. The recommended benchmark ADR for screening examinations is 20% (15% for women and 25% for men ≥50 y). There are few data available to compare ADRs from surveillance vs screening colonoscopies. We used a population-based registry to compare ADRs from screening vs surveillance colonoscopies. The serrated polyp detection rate (SDR), a potential new quality indicator, also was examined. By using data from the statewide New Hampshire Colonoscopy Registry, we excluded incomplete and diagnostic colonoscopies, and those performed in patients with inflammatory bowel disease, familial syndromes, or poor bowel preparation. We calculated the ADR and SDR (number of colonoscopies with at least 1 adenoma or serrated polyp detected, respectively, divided by the number of colonoscopies) from 9100 colonoscopies. The ADR and SDR were compared by colonoscopy indication (screening, surveillance), age at colonoscopy (50-64 y, ≥65 y), and sex. The ADR was significantly higher in surveillance colonoscopies (37%) than screening colonoscopies (25%; P < .001). This difference was observed for both sexes and age groups. There was a smaller difference in the SDR of screening (8%) vs surveillance colonoscopies (10%; P < .001). In a population-based study, we found that addition of data from surveillance colonoscopies increased the ADR but had a smaller effect on the SDR. These findings indicate that when calculating ADR as a quality measure, endoscopists should use screening, rather than surveillance colonoscopy, data. Copyright © 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.

  15. Prevalence of human papilloma virus and human herpes virus types 1-7 in human nasal polyposis.

    PubMed

    Zaravinos, Apostolos; Bizakis, John; Spandidos, Demetrios A

    2009-09-01

    This study aimed to investigate the prevalence of human papilloma virus (HPV), herpes simplex virus-1/-2 (HSV-1/-2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human herpes virus-6/-7 (HHV-6/-7) in 23 human nasal polyps by applying PCR. Two types of control tissues were used: adjacent inferior/middle turbinates from the patients and inferior/middle turbinates from 13 patients undergoing nasal corrective surgery. EBV was the virus most frequently detected (35%), followed by HPV (13%), HSV-1 (9%), and CMV (4%). The CMV-positive polyp was simultaneously positive for HSV-1. HPV was also detected in the adjacent turbinates (4%) and the adjacent middle turbinate (4%) of one of the HPV-positive patients. EBV, HSV, and CMV were not detected in the adjacent turbinates of the EBV-, HSV- or CMV-positive patients. All mucosae were negative for the VZV, HHV-6, and HHV-7. This is the first study to deal with the involvement of a comparable group of viruses in human nasal polyposis. The findings support the theory that the presence of viral EBV markedly influences the pathogenesis of these benign nasal tumors. The low incidence of HPV detected confirms the hypothesis that HPV is correlated with infectious mucosal lesions to a lesser extent than it is with proliferative lesions, such as inverted papilloma. The low incidence of HSV-1 and CMV confirms that these two herpes viruses may play a minor role in the development of nasal polyposis. Double infection with HSV-1 and CMV may also play a minor, though causative, role in nasal polyp development. VZV and HHV-6/-7 do not appear to be involved in the pathogenesis of these mucosal lesions.

  16. Differences in Detection Rates of Adenomas and Serrated Polyps in Screening Versus Surveillance Colonoscopies, Based on the New Hampshire Colonoscopy Registry

    PubMed Central

    ANDERSON, JOSEPH C.; BUTTERLY, LYNN; GOODRICH, MARTHA; ROBINSON, CHRISTINA M.; WEISS, JULIA E.

    2013-01-01

    BACKGROUND & AIMS The adenoma detection rate (ADR) is an important quality indicator originally developed for screening colonoscopies. However, it is unclear whether the ADR should be calculated using data from screening and surveillance examinations. The recommended benchmark ADR for screening examinations is 20% (15% for women and 25% for men ≥ 50 y). There are few data available to compare ADRs from surveillance vs screening colonoscopies. We used a population-based registry to compare ADRs from screening vs surveillance colonoscopies. The serrated polyp detection rate (SDR), a potential new quality indicator, also was examined. METHODS By using data from the statewide New Hampshire Colonoscopy Registry, we excluded incomplete and diagnostic colonoscopies, and those performed in patients with inflammatory bowel disease, familial syndromes, or poor bowel preparation. We calculated the ADR and SDR (number of colonoscopies with at least 1 adenoma or serrated polyp detected, respectively, divided by the number of colonoscopies) from 9100 colonoscopies. The ADR and SDR were compared by colonoscopy indication (screening, surveillance), age at colonoscopy (50–64 y, ≥65 y), and sex. RESULTS The ADR was significantly higher in surveillance colonoscopies (37%) than screening colonoscopies (25%; P < .001). This difference was observed for both sexes and age groups. There was a smaller difference in the SDR of screening (8%) vs surveillance colonoscopies (10%; P < .001). CONCLUSIONS In a population-based study, we found that addition of data from surveillance colonoscopies increased the ADR, but had a smaller effect on the SDR. These findings indicate that when calculating ADR as a quality measure, endoscopists should use screening, rather than surveillance colonoscopy, data. PMID:23660415

  17. Polyphosphate colocalizes with factor XII on platelet-bound fibrin and augments its plasminogen activator activity

    PubMed Central

    Lionikiene, Ausra S.; Georgiev, Georgi; Klemmer, Anja; Brain, Chelsea; Kim, Paul Y.

    2016-01-01

    Activated factor XII (FXIIa) has plasminogen activator capacity but its relative contribution to fibrinolysis is considered marginal compared with urokinase and tissue plasminogen activator. Polyphosphate (polyP) is released from activated platelets and mediates FXII activation. Here, we investigate the contribution of polyP to the plasminogen activator function of αFXIIa. We show that both polyP70, of the chain length found in platelets (60-100 mer), and platelet-derived polyP significantly augment the plasminogen activation capacity of αFXIIa. PolyP70 stimulated the autoactivation of FXII and subsequent plasminogen activation, indicating that once activated, αFXIIa remains bound to polyP70. Indeed, complex formation between polyP70 and αFXIIa provides protection against autodegradation. Plasminogen activation by βFXIIa was minimal and not enhanced by polyP70, highlighting the importance of the anion binding site. PolyP70 did not modulate plasmin activity but stimulated activation of Glu and Lys forms of plasminogen by αFXIIa. Accordingly, polyP70 was found to bind to FXII, αFXIIa, and plasminogen, but not βFXIIa. Fibrin and polyP70 acted synergistically to enhance αFXIIa-mediated plasminogen activation. The plasminogen activator activity of the αFXIIa-polyP70 complex was modulated by C1 inhibitor and histidine-rich glycoprotein, but not plasminogen activator inhibitors 1 and 2. Platelet polyP and FXII were found to colocalize on the activated platelet membrane in a fibrin-dependent manner and decorated fibrin strands extending from platelet aggregates. We show that in the presence of platelet polyP and the downstream substrate fibrin, αFXIIa is a highly efficient and favorable plasminogen activator. Our data are the first to document a profibrinolytic function of platelet polyP. PMID:27694320

  18. Polyp on ultrasound: now what? The association between gallbladder polyps and cancer.

    PubMed

    Donald, Graham; Sunjaya, Dharma; Donahue, Timothy; Hines, O Joe

    2013-10-01

    The association between gallbladder polyps (GBP) and gallbladder cancer (GBC) is unclear. We sought to determine the association between preoperative diagnosis of GBP on imaging and GBC. A retrospective review of patients over 9 years was conducted using International Classification of Diseases, 9th Revision codes for GBP and GBC who underwent cholecystectomy at our institution. Demographics, imaging findings, and pathology results were recorded. A total of 2416 patients underwent cholecystectomy during the study period. Twenty-seven had an operation for GBP either as a result of concern for size or symptoms. Polyp sizes were categorized as less than 1 cm, 1 to 2 cm, or 2 cm or greater. Twenty-four patients in this group (88.9%) had no evidence of high-grade dysplasia or cancer and all of these benign polyps were 2 cm or less on imaging. One patient with a 2.4-cm polyp had high-grade dysplasia, and two patients with polyps over 3 cm had adenocarcinoma. During the same period, 20 patients had an operation for GBC with two patients common to the polyp group. The group of patients with noncancerous polyps was significantly younger than the cancer group (polyps and no polyps). The cancer group was more likely to be symptomatic. Therefore, polyps over 2 cm should be removed given the risk of high-grade dysplasia and cancer above this size. Polyps less than 2 cm were not associated with high-grade dysplasia or cancer and thus surgery may not be required. Intermediate- and small-sized polyps can be monitored with serial ultrasound, especially in younger, asymptomatic patients in whom the risk of malignancy is low.

  19. Photoacoustic Imaging for Differential Diagnosis of Benign Polyps versus Malignant Polyps of the Gallbladder: A Preliminary Study

    PubMed Central

    Chae, Hee-Dong; Jang, Jin-Young; Chang, Jin Ho; Kang, Jeeun; Kang, Mee Joo; Han, Joon Koo

    2017-01-01

    Objective To investigate the feasibility of ex vivo multispectral photoacoustic (PA) imaging in differentiating cholesterol versus neoplastic polyps, and benign versus malignant polyps, of the gallbladder. Materials and Methods A total of 38 surgically confirmed gallbladder polyps (24 cholesterol polyps, 4 adenomas, and 10 adenocarcinomas) from 38 patients were prospectively included in this study. The surgical specimens were set on a gel pad immersed in a saline-filled container. The PA intensities of polyps were then measured, using two separate wavelength intervals (421–647 nm and 692–917 nm). Mann-Whitney U test was performed for the comparison of normalized PA intensities between the cholesterol and neoplastic polyps, and between the benign and malignant polyps. Kruskal-Wallis test was conducted for the comparison of normalized PA intensities among the cholesterol polyps, adenomas, and adenocarcinomas. Results A significant difference was observed in the normalized PA intensities between the cholesterol and neoplastic polyps at 459 nm (median, 1.00 vs. 0.73; p = 0.032). Comparing the benign and malignant polyps, there were significant differences in the normalized PA intensities at 765 nm (median, 0.67 vs. 0.78; p = 0.013), 787 nm (median, 0.65 vs. 0.77; p = 0.034), and 853 nm (median, 0.59 vs. 0.85; p = 0.028). The comparison of the normalized PA intensities among cholesterol polyps, adenomas, and adenocarcinomas demonstrated marginally significant differences at 765 nm (median, 0.67 vs. 0.66 vs. 0.78, respectively; p = 0.049). Conclusion These preliminary results indicate that benign versus malignant gallbladder polyps might exhibit different spectral patterns on multispectral PA imaging. PMID:28860899

  20. Robust Nucleus/Cell Detection and Segmentation in Digital Pathology and Microscopy Images: A Comprehensive Review.

    PubMed

    Xing, Fuyong; Yang, Lin

    2016-01-01

    Digital pathology and microscopy image analysis is widely used for comprehensive studies of cell morphology or tissue structure. Manual assessment is labor intensive and prone to interobserver variations. Computer-aided methods, which can significantly improve the objectivity and reproducibility, have attracted a great deal of interest in recent literature. Among the pipeline of building a computer-aided diagnosis system, nucleus or cell detection and segmentation play a very important role to describe the molecular morphological information. In the past few decades, many efforts have been devoted to automated nucleus/cell detection and segmentation. In this review, we provide a comprehensive summary of the recent state-of-the-art nucleus/cell segmentation approaches on different types of microscopy images including bright-field, phase-contrast, differential interference contrast, fluorescence, and electron microscopies. In addition, we discuss the challenges for the current methods and the potential future work of nucleus/cell detection and segmentation.

  1. Nasal polyps

    MedlinePlus

    ... get rid of nasal polyps. Nasal steroid sprays shrink polyps. They help clear blocked nasal passages and ... is stopped. Corticosteroid pills or liquid may also shrink polyps, and can reduce swelling and nasal congestion. ...

  2. Revisiting the potential signs of colorectal cancer on contrast-enhanced computed tomography without bowel preparation.

    PubMed

    Naqvi, Jawad; Hosmane, Sharath; Lapsia, Snehal

    2015-10-01

    Colorectal cancer (CRC) is the second most common cause of cancer death in the US. Earlier detection can allow treatment with curative intent and improve prognosis. Optical and virtual colonoscopy are widely used in screening for colonic polyps and in the investigation of suspected CRC. However, contrast-enhanced computed tomography (CT) is still performed to investigate various non-specific abdominal complaints. Hence, a significant number of CRC are identified on contrast-enhanced CT without bowel preparation. We describe several signs, which when present in tandem, raise suspicion of CRC, and may warrant further investigation with optical colonoscopy. These include an intraluminal mass, eccentric or circumferential wall thickening >3 mm, focal wall enhancement, pericolic fat stranding, a cluster of >3 local lymph nodes, and enlarged lymph nodes >10 mm in short axis. Multiplanar evaluation of the bowel should be performed on all CT abdominal studies, including those without bowel preparation, to identify subtle features of CRC.

  3. PACS-Based Computer-Aided Detection and Diagnosis

    NASA Astrophysics Data System (ADS)

    Huang, H. K. (Bernie); Liu, Brent J.; Le, Anh HongTu; Documet, Jorge

    The ultimate goal of Picture Archiving and Communication System (PACS)-based Computer-Aided Detection and Diagnosis (CAD) is to integrate CAD results into daily clinical practice so that it becomes a second reader to aid the radiologist's diagnosis. Integration of CAD and Hospital Information System (HIS), Radiology Information System (RIS) or PACS requires certain basic ingredients from Health Level 7 (HL7) standard for textual data, Digital Imaging and Communications in Medicine (DICOM) standard for images, and Integrating the Healthcare Enterprise (IHE) workflow profiles in order to comply with the Health Insurance Portability and Accountability Act (HIPAA) requirements to be a healthcare information system. Among the DICOM standards and IHE workflow profiles, DICOM Structured Reporting (DICOM-SR); and IHE Key Image Note (KIN), Simple Image and Numeric Report (SINR) and Post-processing Work Flow (PWF) are utilized in CAD-HIS/RIS/PACS integration. These topics with examples are presented in this chapter.

  4. Registration of prone and supine CT colonography scans using correlation optimized warping and canonical correlation analysis

    PubMed Central

    Wang, Shijun; Yao, Jianhua; Liu, Jiamin; Petrick, Nicholas; Van Uitert, Robert L.; Periaswamy, Senthil; Summers, Ronald M.

    2009-01-01

    Purpose: In computed tomographic colonography (CTC), a patient will be scanned twice—Once supine and once prone—to improve the sensitivity for polyp detection. To assist radiologists in CTC reading, in this paper we propose an automated method for colon registration from supine and prone CTC scans. Methods: We propose a new colon centerline registration method for prone and supine CTC scans using correlation optimized warping (COW) and canonical correlation analysis (CCA) based on the anatomical structure of the colon. Four anatomical salient points on the colon are first automatically distinguished. Then correlation optimized warping is applied to the segments defined by the anatomical landmarks to improve the global registration based on local correlation of segments. The COW method was modified by embedding canonical correlation analysis to allow multiple features along the colon centerline to be used in our implementation. Results: We tested the COW algorithm on a CTC data set of 39 patients with 39 polyps (19 training and 20 test cases) to verify the effectiveness of the proposed COW registration method. Experimental results on the test set show that the COW method significantly reduces the average estimation error in a polyp location between supine and prone scans by 67.6%, from 46.27±52.97 to 14.98 mm±11.41 mm, compared to the normalized distance along the colon centerline algorithm (p<0.01). Conclusions: The proposed COW algorithm is more accurate for the colon centerline registration compared to the normalized distance along the colon centerline method and the dynamic time warping method. Comparison results showed that the feature combination of z-coordinate and curvature achieved lowest registration error compared to the other feature combinations used by COW. The proposed method is tolerant to centerline errors because anatomical landmarks help prevent the propagation of errors across the entire colon centerline. PMID:20095272

  5. Registration of prone and supine CT colonography scans using correlation optimized warping and canonical correlation analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang Shijun; Yao Jianhua; Liu Jiamin

    Purpose: In computed tomographic colonography (CTC), a patient will be scanned twice--Once supine and once prone--to improve the sensitivity for polyp detection. To assist radiologists in CTC reading, in this paper we propose an automated method for colon registration from supine and prone CTC scans. Methods: We propose a new colon centerline registration method for prone and supine CTC scans using correlation optimized warping (COW) and canonical correlation analysis (CCA) based on the anatomical structure of the colon. Four anatomical salient points on the colon are first automatically distinguished. Then correlation optimized warping is applied to the segments defined bymore » the anatomical landmarks to improve the global registration based on local correlation of segments. The COW method was modified by embedding canonical correlation analysis to allow multiple features along the colon centerline to be used in our implementation. Results: We tested the COW algorithm on a CTC data set of 39 patients with 39 polyps (19 training and 20 test cases) to verify the effectiveness of the proposed COW registration method. Experimental results on the test set show that the COW method significantly reduces the average estimation error in a polyp location between supine and prone scans by 67.6%, from 46.27{+-}52.97 to 14.98 mm{+-}11.41 mm, compared to the normalized distance along the colon centerline algorithm (p<0.01). Conclusions: The proposed COW algorithm is more accurate for the colon centerline registration compared to the normalized distance along the colon centerline method and the dynamic time warping method. Comparison results showed that the feature combination of z-coordinate and curvature achieved lowest registration error compared to the other feature combinations used by COW. The proposed method is tolerant to centerline errors because anatomical landmarks help prevent the propagation of errors across the entire colon centerline.« less

  6. Snaring large serrated polyps.

    PubMed

    Liang, Jennifer; Kalady, Matthew F; Church, James

    2013-05-01

    Serrated polyps of the large bowel are potentially premalignant, difficult to see, but important to remove. Few studies describe the technique or outcomes of serrated polypectomy. We sought to present outcomes of a series of polypectomies of large serrated polyps in comparison to a series of endoscopic resections of large adenomas. This retrospective, comparative, single endoscopist study was performed in an outpatient colonoscopy department of a tertiary referral medical center. Patients had outpatient colonoscopy where a large (≥2 cm) serrated polyp or adenoma was removed. Outcomes were completeness of excision and complications of polypectomy. A database of endoscopic polypectomies was reviewed. Polypectomy of large serrated polyps was compared with polypectomy of large adenomas. There were 132 large serrated polyps in 112 patients and 563 adenomas in 428 patients. More serrated polyps were right sided (120 of 130, 92.3 %, vs. 379 of 563, 67 %) (p < 0.0001). The serrated polyps were smaller than the adenomas (mean 25.5 ± 7.9 mm standard deviation) versus 36.8 ± 16.9 mm standard deviation (p < 0.001). There were four complications of serrated polypectomy in four patients (4 % of polyps, 5 % of patients): three postpolypectomy bleeds and one postpolypectomy syndrome. There were 33 complications of adenoma removal (31 postpolypectomy bleeding and two postpolypectomy syndrome) (6.9 % of polyps, p = 0.376, 8.4 % of patients, p = 0.371). On follow-up, 36 of 51 patients (71 %) with serrated polyps had metachronous lesions compared to 133 of 298 patients (45 %) with adenomas (p < 0.0001). There were fewer residual polyps in the serrated group (4 of 47 vs. 64 of 298, p = 0.001). Removal of large serrated colorectal polyps is no more complicated than polypectomy of similarly sized adenomas. However, large serrated polyps have a higher rate of metachronous polyps than similarly sized adenomas and surveillance should be adapted to reflect these findings.

  7. Molecular characterization of colorectal adenomas with and without malignancy reveals distinguishing genome, transcriptome and methylome alterations.

    PubMed

    Druliner, Brooke R; Wang, Panwen; Bae, Taejeong; Baheti, Saurabh; Slettedahl, Seth; Mahoney, Douglas; Vasmatzis, Nikolaos; Xu, Hang; Kim, Minsoo; Bockol, Matthew; O'Brien, Daniel; Grill, Diane; Warner, Nathaniel; Munoz-Gomez, Miguel; Kossick, Kimberlee; Johnson, Ruth; Mouchli, Mohamad; Felmlee-Devine, Donna; Washechek-Aletto, Jill; Smyrk, Thomas; Oberg, Ann; Wang, Junwen; Chia, Nicholas; Abyzov, Alexej; Ahlquist, David; Boardman, Lisa A

    2018-02-16

    The majority of colorectal cancer (CRC) arises from precursor lesions known as polyps. The molecular determinants that distinguish benign from malignant polyps remain unclear. To molecularly characterize polyps, we utilized Cancer Adjacent Polyp (CAP) and Cancer Free Polyp (CFP) patients. CAPs had tissues from the residual polyp of origin and contiguous cancer; CFPs had polyp tissues matched to CAPs based on polyp size, histology and dysplasia. To determine whether molecular features distinguish CAPs and CFPs, we conducted Whole Genome Sequencing, RNA-seq, and RRBS on over 90 tissues from 31 patients. CAPs had significantly more mutations, altered expression and hypermethylation compared to CFPs. APC was significantly mutated in both polyp groups, but mutations in TP53, FBXW7, PIK3CA, KIAA1804 and SMAD2 were exclusive to CAPs. We found significant expression changes between CAPs and CFPs in GREM1, IGF2, CTGF, and PLAU, and both expression and methylation alterations in FES and HES1. Integrative analyses revealed 124 genes with alterations in at least two platforms, and ERBB3 and E2F8 showed aberrations specific to CAPs across all platforms. These findings provide a resource of molecular distinctions between polyps with and without cancer, which have the potential to enhance the diagnosis, risk assessment and management of polyps.

  8. Body mass index is an independent risk factor for the development of endometrial polyps in patients undergoing in vitro fertilization.

    PubMed

    Onalan, Reside; Onalan, Gogsen; Tonguc, Esra; Ozdener, Tulin; Dogan, Muammer; Mollamahmutoglu, Leyla

    2009-04-01

    To determine the subgroup of patients in whom office hysteroscopy should be routinely performed before an in vitro fertilization (IVF) program. Retrospective cohort analysis. Tertiary education and research hospital. Two hundred twenty-three patients who underwent a uterine evaluation by office hysteroscopy before the IVF and embryo transfer cycle. The office hysteroscopy was performed in the follicular phase of the menstrual cycle before the IVF cycle. The office findings: number of polyps, number of multiple polyps, and polyp size. Patients with polycystic ovary syndrome (PCOS) had a higher number of endometrial polyps, but the difference was not statistically significant (28.9% vs. 18.3%). When comparing the patients according to BMI, patients with BMI >or=30 had a statistically significantly higher number of endometrial polyps versus BMI <30 (52% vs. 15%). On the other hand, obesity was positively correlated with the occurrence of polyps, size of the polyps, and occurrence of multiple number of polyps in the correlation analysis. In addition, logistic regression analysis using age, obesity, duration of infertility, and estradiol levels revealed that obesity was an independent prognostic factor for the development of endometrial polyps. Office hysteroscopy should be performed in patients with BMI >or=30 because obesity may act as an initiator for the pathogenesis of endometrial polyps.

  9. Biopsy forceps is inadequate for the resection of diminutive polyps.

    PubMed

    Efthymiou, M; Taylor, A C; Desmond, P V; Allen, P B; Chen, R Y

    2011-04-01

    Cold biopsy forceps polypectomy (CBP) is often used for the removal of diminutive polyps. The efficacy of the technique has not been thoroughly assessed. The aim of this study was to prospectively assess the efficacy of CBP for removing diminutive polyps. This was a prospective study from St Vincent's Hospital, a tertiary referral hospital in Melbourne, Australia. A total of 143 patients were screened and 52 patients with ≥ 1 diminutive polyps were enrolled. CBP was used to resect diminutive polyps until no polyp tissue was visible. The polyp base was then resected using endoscopic mucosal resection (EMR) with a 1 - 2-mm margin. The CBP and EMR samples were compared to assess completeness of the resection. Overall 39 % (21 / 54) of diminutive polyps were completely resected using CBP. After binary logistic regression analysis, polyp histology was found to be predictive of resection, with complete resection of 62 % (13 / 21) for adenomas and 24 % (8 / 33) for hyperplastic polyps (odds ratio 5.1; P = 0.008). The size and number of bites taken with the forceps were not predictive of complete response. Within the limitations of a modest sample size, CBP appears to be inadequate treatment for the removal of diminutive polyps. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Diagnosis and management of gallbladder polyps.

    PubMed

    Gallahan, William C; Conway, Jason D

    2010-06-01

    Gallbladder polyps are frequently encountered on cross-sectional imaging, often in asymptomatic patients. Most are benign and of little clinical importance. However, some polyps do have a malignant potential. This article discusses the clinical presentation, diagnosis, and natural history of gallbladder polyps and risk factors for malignant polyps and indications for cholecystectomy. Copyright 2010 Elsevier Inc. All rights reserved.

  11. Inflammatory nasal polyps: an unusual late complication of Silastic sheet repair of orbital floor fracture.

    PubMed

    Andrews, A E; Hicklin, L

    2006-02-01

    Silastic implants are very widely used in surgical practice and are considered to be relatively inert. They do however present with complications, including infection, local foreign body inflammatory response,calcification, migration and failure of repair of the defect, which sometimes may necessitate explantation. Head and neck implants do present a special case, as complications can cause obstruction and disruption of function in small cavities. A pertinent history, clinical review and computed tomography scan are usually invaluable in obtaining a diagnosis. We present a rare case of migrated Silastic orbital sheet, presenting as a nasal polyp and causing maxillary antral pain and infection. A detailed search of the medical literature revealed no other such case.

  12. Diagnosis and management of gallbladder polyps.

    PubMed

    Andrén-Sandberg, Ake

    2012-05-01

    Gallbladder cancer is a rather uncommon disease, when it gives symptoms it has usually reached an incurable stage. Therefore, every attempt must be made to find the asymptomatic stages and look for premalignant gallbladder polyps. Even if gallbladder cancer is a rare disease, gallbladder polyps are common, only a few polyps develop to cancer. This makes gallbladder polyps another problem: which are the polyps that must be surgically removed, which shall be followed-up, or for how long? The author used the keyword "gallbladder polypsn" in PubMed and reviewed the scientific literatures published from January 2000 to December 2011. The present review article has summarized almost all respects of gallbladder polyp, including the risk factors, clinical diagnosis and management, and comments made from the author, in which clinical treatments are recommended. It is author's purpose that the 11-year-knowledge about gallbladder polyps summarized from all worlds' literatures is enough to know how clinicians will handle the next patient with gallbladder polyp.

  13. Diagnosis and Management of Gallbladder Polyps

    PubMed Central

    Andrén-Sandberg, Åke

    2012-01-01

    Gallbladder cancer is a rather uncommon disease, when it gives symptoms it has usually reached an incurable stage. Therefore, every attempt must be made to find the asymptomatic stages and look for premalignant gallbladder polyps. Even if gallbladder cancer is a rare disease, gallbladder polyps are common, only a few polyps develop to cancer. This makes gallbladder polyps another problem: which are the polyps that must be surgically removed, which shall be followed-up, or for how long? The author used the keyword “gallbladder polypsn” in PubMed and reviewed the scientific literatures published from January 2000 to December 2011. The present review article has summarized almost all respects of gallbladder polyp, including the risk factors, clinical diagnosis and management, and comments made from the author, in which clinical treatments are recommended. It is author's purpose that the 11-year-knowledge about gallbladder polyps summarized from all worlds’ literatures is enough to know how clinicians will handle the next patient with gallbladder polyp. PMID:22655278

  14. Malignant transformation of a 5-mm gallbladder polyp over 2 years: a case report and review of current literature.

    PubMed

    Lu, Darren; Radin, Randall; Yung, Evan; Tchelepi, Hisham

    2015-03-01

    Gallbladder polyps (GBPs) are incidentally seen in 4% to 7% of adults on abdominal ultrasounds. Most GBPs are benign cholesterol polyps, adenomyomatosis, or inflammatory polyps. Currently, cholecystectomy is widely accepted as appropriate care for polyps 10 mm or larger as they present a higher risk for malignancy. However, the management of small polyps smaller than 10 mm has continued to be a dilemma to clinicians and radiologists. Many authors support a nonoperative approach with imaging follow-up for polyps smaller than 10 mm, as most have been shown to be benign. However, small polyps do have the potential to be neoplastic adenomas and become malignant. In this report, we will describe a case of a tiny GBP that subsequently developed into a 20-mm carcinoma over a period of 2 years.

  15. Surgical Management of Endometrial Polyps in Infertile Women: A Comprehensive Review

    PubMed Central

    Petrini, Allison C.; Lekovich, Jovana P.; Elias, Rony T.; Spandorfer, Steven D.

    2015-01-01

    Endometrial polyps are benign localized lesions of the endometrium, which are commonly seen in women of reproductive age. Observational studies have suggested a detrimental effect of endometrial polyps on fertility. The natural course of endometrial polyps remains unclear. Expectant management of small and asymptomatic polyps is reasonable in many cases. However, surgical resection of endometrial polyps is recommended in infertile patients prior to treatment in order to increase natural conception or assisted reproductive pregnancy rates. There is mixed evidence regarding the resection of newly diagnosed endometrial polyps during ovarian stimulation to improve the outcomes of fresh in vitro fertilization cycles. Hysteroscopy polypectomy remains the gold standard for surgical treatment. Evidence regarding the cost and efficacy of different methods for hysteroscopic resection of endometrial polyps in the office and outpatient surgical settings has begun to emerge. PMID:26301260

  16. Association of Endotoxins and Colon Polyp: A Case-Control Study

    PubMed Central

    Lee, Kang-Kon

    2012-01-01

    Endotoxins are known to be associated with the occurrence of various chronic diseases. This study was conducted to investigate the role of endotoxins in the pathogenesis of colon polyps through a case-control study. A total of 145 subjects (74 subjects in the polyp group and 71 subjects in the control group) had undergone a colonoscopy. Age, body mass index (BMI) and endotoxin levels were found to be significantly higher in the polyp group than in the control group. The endotoxin level was still significantly higher in the polyp group than in the control group, even after age and BMI had been adjusted (polyp group 0.108 ± 0.007 EU/mL, control group 0.049 ± 0.008 EU/mL, P < 0.001). In subgroup analysis, the endotoxin level significantly increased in accordance with the number of colon polyps (one-polyp group, 0.088 ± 0.059 EU/mL; two-polyp group, 0.097 ± 0.071 EU/mL; three-or-more-polyp group, 0.149 ± 0.223 EU/mL). The endotoxin levels also significantly increased in groups with tubular adenoma with high-grade dysplasia (hyperplastic polyp group, 0.109 ± 0.121 EU/mL; tubular adenoma with low grade dysplasia group, 0.103 ± 0.059 EU/mL; tubular adenoma with high grade dysplasia group, 2.915 ± 0.072 EU/mL). In conclusion, the serum level of endotoxins is quantitatively correlated with colon polyps. PMID:22969253

  17. Natural Language Processing Accurately Calculates Adenoma and Sessile Serrated Polyp Detection Rates.

    PubMed

    Nayor, Jennifer; Borges, Lawrence F; Goryachev, Sergey; Gainer, Vivian S; Saltzman, John R

    2018-07-01

    ADR is a widely used colonoscopy quality indicator. Calculation of ADR is labor-intensive and cumbersome using current electronic medical databases. Natural language processing (NLP) is a method used to extract meaning from unstructured or free text data. (1) To develop and validate an accurate automated process for calculation of adenoma detection rate (ADR) and serrated polyp detection rate (SDR) on data stored in widely used electronic health record systems, specifically Epic electronic health record system, Provation ® endoscopy reporting system, and Sunquest PowerPath pathology reporting system. Screening colonoscopies performed between June 2010 and August 2015 were identified using the Provation ® reporting tool. An NLP pipeline was developed to identify adenomas and sessile serrated polyps (SSPs) on pathology reports corresponding to these colonoscopy reports. The pipeline was validated using a manual search. Precision, recall, and effectiveness of the natural language processing pipeline were calculated. ADR and SDR were then calculated. We identified 8032 screening colonoscopies that were linked to 3821 pathology reports (47.6%). The NLP pipeline had an accuracy of 100% for adenomas and 100% for SSPs. Mean total ADR was 29.3% (range 14.7-53.3%); mean male ADR was 35.7% (range 19.7-62.9%); and mean female ADR was 24.9% (range 9.1-51.0%). Mean total SDR was 4.0% (0-9.6%). We developed and validated an NLP pipeline that accurately and automatically calculates ADRs and SDRs using data stored in Epic, Provation ® and Sunquest PowerPath. This NLP pipeline can be used to evaluate colonoscopy quality parameters at both individual and practice levels.

  18. Inhibition of intestinal polyp growth by oral ingestion of bovine lactoferrin and immune cells in the large intestine.

    PubMed

    Iigo, Masaaki; Alexander, David B; Xu, Jiegou; Futakuchi, Mitsuru; Suzui, Masumi; Kozu, Takahiro; Akasu, Takayuki; Saito, Daizo; Kakizoe, Tadao; Yamauchi, Koji; Abe, Fumiaki; Takase, Mitsunori; Sekine, Kazunori; Tsuda, Hiroyuki

    2014-10-01

    Studies using animal models have demonstrated that ingestion of bovine lactoferrin (bLF) inhibits carcinogenesis in the colon and other organs of experimental animals. As a result of these studies, a blinded, randomized, controlled clinical trial was conducted in the National Cancer Center Hospital, Tokyo, Japan to determine whether ingestion of bLF had an effect on the growth of colorectal polyps in humans. Patients with colorectal polyps ≤5 mm diameter and likely to be adenomas ingested 0, 1.5, or 3.0 g bLF daily for 1 year. Ingestion of 3.0 g bLF suppressed the growth of colorectal polyps and increased the level of serum human lactoferrin in trial participants 63 years old or younger. The purpose of the present study was to investigate correlations between immune parameters and changes in polyp size. Trial participants with regressing polyps had increased NK cell activity, increased serum hLF levels (indicating increased neutrophil activity), and increased numbers of CD4+ cells in the polyps. These findings are consistent with a correlation between higher immune activity and suppression of colorectal polyps. In addition, participants with regressing polyps had lower numbers of PMNs and increased numbers of S100A8+ cells in the polyps, consistent with a correlation between lower inflammatory potential in the colon and suppression of colorectal polyps. Trial participants ingesting bLF had increased serum hLF levels, a possible increase in systemic NK cell activity, and increased numbers of CD4+ and CD161+ cells in the polyps. Taken together, our findings suggest that bLF suppressed colorectal polyps by enhancing immune responsiveness.

  19. THE PREVALENCE OF COLONIC POLYPS IN PATIENTS WITH ACROMEGALY: A CASE-CONTROL, NESTED IN A COHORT COLONOSCOPIC STUDY.

    PubMed

    Gonzalez, Baldomero; Vargas, Guadalupe; Mendoza, Victoria; Nava, Mariana; Rojas, Moisés; Mercado, Moisés

    2017-05-01

    Acromegaly is associated with an increased risk of colonic polyps. The magnitude of such risk is controversial, and the characteristics that distinguish patients who develop polyps from those who do not are not well established. This study was performed to determine the prevalence of colonic polyps upon the diagnosis of acromegaly and to compare the clinical and biochemical features of patients with and without polyps. Out of 165 patients who underwent a full colonoscopy upon diagnosis of acromegaly, 53 were found to harbor colonic lesions (cases), whereas the remaining 112 were used as controls. Demographic, clinical, and biochemical characteristics were compared between the 2 groups. The prevalence of colonic polyps was 32%, with an estimated relative risk of 6.21 (95% confidence interval [CI] 4.08-9.48). Adenomatous and nonadenomatous polyps were found in 22 and 31 patients, respectively. The most common location was the descending colon. Compared to patients without polyps, subjects with polyps were somewhat older and had significantly higher insulin-like growth factor-1 (IGF-1) levels and a higher prevalence of diabetes. Upon multivariate analysis, only IGF-1 level at diagnosis remained significantly associated with colonic polyps in general and with hyperplastic polyps in particular. Acromegaly is associated with an elevated risk of developing colonic polyps, particularly, distally located hyperplastic lesions. Except for a higher IGF-1 level at diagnosis, no distinctive clinical or biochemical features can be found among those who develop polyps compared to those who do not. CI = confidence interval GH = growth hormone IGF-1 = insulin-like growth factor 1 IQR = inter-quartile range RR = relative risk ULN = upper limit of normal.

  20. Computed-aided diagnosis (CAD) in the detection of breast cancer.

    PubMed

    Dromain, C; Boyer, B; Ferré, R; Canale, S; Delaloge, S; Balleyguier, C

    2013-03-01

    Computer-aided detection (CAD) systems have been developed for interpretation to improve mammographic detection of breast cancer at screening by reducing the number of false-negative interpretation that can be caused by subtle findings, radiologist distraction and complex architecture. They use a digitized mammographic image that can be obtained from both screen-film mammography and full field digital mammography. Its performance in breast cancer detection is dependent on the performance of the CAD itself, the population to which it is applied and the radiologists who use it. There is a clear benefit to the use of CAD in less experienced radiologist and in detecting breast carcinomas presenting as microcalcifications. This review gives a detailed description CAD systems used in mammography and their performance in assistance of reading in screening mammography and as an alternative to double reading. Other CAD systems developed for MRI and ultrasound are also presented and discussed. Copyright © 2012. Published by Elsevier Ireland Ltd.

  1. Mechanisms of interaction between macroalgae and scleractinians on a coral reef in Jamaica.

    PubMed

    River, G F.; Edmunds, P J.

    2001-07-01

    After several decades of disturbance, many coral reefs in the Caribbean are dominated by macroalgae. One process affecting this transition is coral-macroalgal competition, yet few studies have addressed the mechanisms involved. In this study, we investigated competition between the tall and bushy macroalga Sargassum hystrix (J. Agardh) and the branching coral Porites porites (Pallas) on a shallow reef in Jamaica. Experiments were designed to expose coral branches to different treatments to test the role of shading and abrasion by Sargassum on coral growth and polyp expansion. Corals exposed to Sargassum grew significantly more slowly (80% reduction) than controls, but this effect was absent when corals were caged to prevent physical contact with macroalgae. Light levels were reduced in both the algal and cage treatments, but shading apparently had little effect on the growth of corals in cages. Short-term measurements of integrated net water flow did not detect variation among treatments. In algal-mimic treatments, where clear plastic strips could touch but not shade the corals, growth rates were 25% lower than controls, but this effect was not statistically significant. Thus, the growth of corals in contact with Sargassum was reduced by abrasion and, to a lesser extent, by factors unique to living macroalgae. Analysis of polyp expansion showed that polyps were more frequently retracted when corals were in contact with macroalgae or algal-mimics compared to controls or cage treatment; the frequency of polyp contraction was correlated positively with growth. Together, these results suggest that abrasion-mediated polyp retraction is one of the primary mechanisms of competition utilized by tall (ca. 17 cm) macroalgae against scleractinian corals.

  2. Molecular features of colorectal polyps presenting Kudo’s type II mucosal crypt pattern: are they based on the same mechanism of tumorigenesis?

    PubMed Central

    Shinmura, Kensuke; Konishi, Kazuo; Yamochi, Toshiko; Kubota, Yutaro; Yano, Yuichiro; Katagiri, Atsushi; Muramoto, Takashi; Kihara, Toshihiro; Tojo, Masayuki; Konda, Kenichi; Tagawa, Teppei; Yanagisawa, Fumito; Kogo, Mari; Makino, Reiko; Takimoto, Masafumi; Yoshida, Hitoshi

    2014-01-01

    Background and study aims: The molecular features of serrated polyps (SPs) with hyperplastic crypt pattern, also called Kudo’s type II observed by chromoendoscopy, were evaluated. Methods: The clinicopathological and molecular features of 114 SPs with a hyperplastic pit pattern detected under chromoendoscopy (five dysplastic SPs, 63 sessile serrated adenoma/polyps (SSA/Ps), 36 microvesicular hyperplastic polyps (MVHPs), and 10 goblet cell-rich hyperplastic polyps (GCHPs)) were examined. The frequency of KRAS and BRAF mutations and CpG island methylator phenotype (CIMP) were investigated. Results: Dysplastic SPs and SSA/Ps were frequently located in the proximal colon compared to others (SSA/Ps vs. MVHPs or GCHPs, P < 0.0001). No significant difference was found in the frequency of BRAF mutation among SPs apart from GCHP (60 % for dysplastic SPs, 44 % for SSA/Ps, 47 % for MVHPs, and 0 % for GCHPs). The frequency of CIMP was higher in dysplastic SPs or SSA/Ps than in MVHPs or GCHPs (60 % for dysplastic SPs, 56 % for SSA/Ps, 32 % for MVHPs, and 10 % for GCHPs) (SSA/Ps vs. GCHP, P = 0.0068). When serrated neoplasias (SNs) and MVHPs were classified into proximal and distal lesions, the frequency of CIMP was significantly higher in the proximal compared to the distal SNs (64 % vs. 11 %, P = 0.0032). Finally, multivariate analysis showed that proximal location and BRAF mutation were significantly associated with an increased risk of CIMP. Conclusions: Distinct molecular features were observed between proximal and distal SPs with hyperplastic crypt pattern. Proximal MVHPs may develop more frequently through SSA/Ps to CIMP cancers than distal MVHPs. PMID:26134964

  3. Molecular features of colorectal polyps presenting Kudo's type II mucosal crypt pattern: are they based on the same mechanism of tumorigenesis?

    PubMed

    Shinmura, Kensuke; Konishi, Kazuo; Yamochi, Toshiko; Kubota, Yutaro; Yano, Yuichiro; Katagiri, Atsushi; Muramoto, Takashi; Kihara, Toshihiro; Tojo, Masayuki; Konda, Kenichi; Tagawa, Teppei; Yanagisawa, Fumito; Kogo, Mari; Makino, Reiko; Takimoto, Masafumi; Yoshida, Hitoshi

    2014-09-01

    The molecular features of serrated polyps (SPs) with hyperplastic crypt pattern, also called Kudo's type II observed by chromoendoscopy, were evaluated. The clinicopathological and molecular features of 114 SPs with a hyperplastic pit pattern detected under chromoendoscopy (five dysplastic SPs, 63 sessile serrated adenoma/polyps (SSA/Ps), 36 microvesicular hyperplastic polyps (MVHPs), and 10 goblet cell-rich hyperplastic polyps (GCHPs)) were examined. The frequency of KRAS and BRAF mutations and CpG island methylator phenotype (CIMP) were investigated. Dysplastic SPs and SSA/Ps were frequently located in the proximal colon compared to others (SSA/Ps vs. MVHPs or GCHPs, P < 0.0001). No significant difference was found in the frequency of BRAF mutation among SPs apart from GCHP (60 % for dysplastic SPs, 44 % for SSA/Ps, 47 % for MVHPs, and 0 % for GCHPs). The frequency of CIMP was higher in dysplastic SPs or SSA/Ps than in MVHPs or GCHPs (60 % for dysplastic SPs, 56 % for SSA/Ps, 32 % for MVHPs, and 10 % for GCHPs) (SSA/Ps vs. GCHP, P = 0.0068). When serrated neoplasias (SNs) and MVHPs were classified into proximal and distal lesions, the frequency of CIMP was significantly higher in the proximal compared to the distal SNs (64 % vs. 11 %, P = 0.0032). Finally, multivariate analysis showed that proximal location and BRAF mutation were significantly associated with an increased risk of CIMP. Distinct molecular features were observed between proximal and distal SPs with hyperplastic crypt pattern. Proximal MVHPs may develop more frequently through SSA/Ps to CIMP cancers than distal MVHPs.

  4. FXIa and platelet polyphosphate as therapeutic targets during human blood clotting on collagen/tissue factor surfaces under flow

    PubMed Central

    Zhu, Shu; Travers, Richard J.; Morrissey, James H.

    2015-01-01

    Factor XIIa (FXIIa) and factor XIa (FXIa) contribute to thrombosis in animal models, whereas platelet-derived polyphosphate (polyP) may potentiate contact or thrombin-feedback pathways. The significance of these mediators in human blood under thrombotic flow conditions on tissue factor (TF) –bearing surfaces remains inadequately resolved. Human blood (corn trypsin inhibitor treated [4 μg/mL]) was tested by microfluidic assay for clotting on collagen/TF at TF surface concentration ([TF]wall) from ∼0.1 to 2 molecules per μm2. Anti-FXI antibodies (14E11 and O1A6) or polyP-binding protein (PPXbd) were used to block FXIIa-dependent FXI activation, FXIa-dependent factor IX (FIX) activation, or platelet-derived polyP, respectively. Fibrin formation was sensitive to 14E11 at 0 to 0.1 molecules per µm2 and sensitive to O1A6 at 0 to 0.2 molecules per µm2. However, neither antibody reduced fibrin generation at ∼2 molecules per µm2 when the extrinsic pathway became dominant. Interestingly, PPXbd reduced fibrin generation at low [TF]wall (0.1 molecules per µm2) but not at zero or high [TF]wall, suggesting a role for polyP distinct from FXIIa activation and requiring low extrinsic pathway participation. Regardless of [TF]wall, PPXbd enhanced fibrin sensitivity to tissue plasminogen activator and promoted clot retraction during fibrinolysis concomitant with an observed PPXbd-mediated reduction of fibrin fiber diameter. This is the first detection of endogenous polyP function in human blood under thrombotic flow conditions. When triggered by low [TF]wall, thrombosis may be druggable by contact pathway inhibition, although thrombolytic susceptibility may benefit from polyP antagonism regardless of [TF]wall. PMID:26136249

  5. CTNNB1-mutant colorectal carcinomas with immediate invasive growth: a model of interval cancers in Lynch syndrome.

    PubMed

    Ahadova, Aysel; von Knebel Doeberitz, Magnus; Bläker, Hendrik; Kloor, Matthias

    2016-10-01

    The implementation of regular colonoscopy programs has significantly decreased the mortality associated with colorectal cancer (CRC) in Lynch syndrome patients. However, interval CRCs in Lynch syndrome that remain undetected by colonoscopy still represent a substantial problem in the management of the syndrome. One possible reason of interval cancers could be a non-polypous pathway of cancer development. To examine the possibility of a non-polypous pathway of CRC development in Lynch syndrome, we analyzed the histological appearance of 46 Lynch syndrome-associated CRCs and compared them to 34 sporadic microsatellite unstable cancers. We observed that 25 (62.5 %) out of 40 assessable Lynch syndrome-associated carcinomas lacked evidence of polypous growth, compared to 17 (50 %) out of 34 sporadic MSI-H cancers. We detected CTNNB1 mutations in 8 (17.4 %) out of 46 Lynch syndrome-associated cancers compared to 0 out of 34 sporadic MSI-H cancers (p = 0.01). The majority of CTNNB1-mutant cancers presented with a histological appearance suggesting immediate invasive growth. Our results suggest that a distinct subgroup of CRCs in Lynch syndrome may in fact emerge from a non-polypous precursor, thus potentially explaining the phenomenon of interval cancers. Such a non-polypous precursor may be the recently described mismatch repair-deficient crypt focus, which remains invisible for the examiner during colonoscopy. This calls for considering the implementation of active, primary preventive measures in the management of Lynch syndrome. Future studies on pathogenic pathways and precursor lesions in Lynch syndrome are strongly encouraged, and the clinical efficacy of new prevention approaches should be evaluated in prospective clinical trials.

  6. Expanding Biosensing Abilities through Computer-Aided Design of Metabolic Pathways.

    PubMed

    Libis, Vincent; Delépine, Baudoin; Faulon, Jean-Loup

    2016-10-21

    Detection of chemical signals is critical for cells in nature as well as in synthetic biology, where they serve as inputs for designer circuits. Important progress has been made in the design of signal processing circuits triggering complex biological behaviors, but the range of small molecules recognized by sensors as inputs is limited. The ability to detect new molecules will increase the number of synthetic biology applications, but direct engineering of tailor-made sensors takes time. Here we describe a way to immediately expand the range of biologically detectable molecules by systematically designing metabolic pathways that transform nondetectable molecules into molecules for which sensors already exist. We leveraged computer-aided design to predict such sensing-enabling metabolic pathways, and we built several new whole-cell biosensors for molecules such as cocaine, parathion, hippuric acid, and nitroglycerin.

  7. Polyphosphate colocalizes with factor XII on platelet-bound fibrin and augments its plasminogen activator activity.

    PubMed

    Mitchell, Joanne L; Lionikiene, Ausra S; Georgiev, Georgi; Klemmer, Anja; Brain, Chelsea; Kim, Paul Y; Mutch, Nicola J

    2016-12-15

    Activated factor XII (FXIIa) has plasminogen activator capacity but its relative contribution to fibrinolysis is considered marginal compared with urokinase and tissue plasminogen activator. Polyphosphate (polyP) is released from activated platelets and mediates FXII activation. Here, we investigate the contribution of polyP to the plasminogen activator function of αFXIIa. We show that both polyP 70 , of the chain length found in platelets (60-100 mer), and platelet-derived polyP significantly augment the plasminogen activation capacity of αFXIIa. PolyP 70 stimulated the autoactivation of FXII and subsequent plasminogen activation, indicating that once activated, αFXIIa remains bound to polyP 70 Indeed, complex formation between polyP 70 and αFXIIa provides protection against autodegradation. Plasminogen activation by βFXIIa was minimal and not enhanced by polyP 70 , highlighting the importance of the anion binding site. PolyP 70 did not modulate plasmin activity but stimulated activation of Glu and Lys forms of plasminogen by αFXIIa. Accordingly, polyP 70 was found to bind to FXII, αFXIIa, and plasminogen, but not βFXIIa. Fibrin and polyP 70 acted synergistically to enhance αFXIIa-mediated plasminogen activation. The plasminogen activator activity of the αFXIIa-polyP 70 complex was modulated by C1 inhibitor and histidine-rich glycoprotein, but not plasminogen activator inhibitors 1 and 2. Platelet polyP and FXII were found to colocalize on the activated platelet membrane in a fibrin-dependent manner and decorated fibrin strands extending from platelet aggregates. We show that in the presence of platelet polyP and the downstream substrate fibrin, αFXIIa is a highly efficient and favorable plasminogen activator. Our data are the first to document a profibrinolytic function of platelet polyP. © 2016 by The American Society of Hematology.

  8. Association of insulin-related serum factors with colorectal polyp number and type in adult males

    PubMed Central

    Comstock, Sarah S.; Xu, Diana; Hortos, Kari; Kovan, Bruce; McCaskey, Sarah; Pathak, Dorothy R.; Fenton, Jenifer I.

    2014-01-01

    Background Dysregulated insulin signaling is thought to contribute to cancer risk. Methods To determine if insulin-related serum factors are associated with colon polyps, 126 asymptomatic men (48–65yr) were recruited at colonoscopy. Blood was collected. Odds ratios were determined using polytomous logistic regression for polyp number and type. Results Males with serum C-peptide concentration >3.3 ng/ml were 3.8 times more likely to have an adenoma relative to no polyp than those with C-peptide ≤1.8 ng/ml. As C-peptide tertile increased, an individual was 2 times more likely to have an adenoma (p=0.01) than no polyp. There were no associations between insulin-like growth factor or its binding proteins with polyp number or type. Males with soluble receptor for advanced glycation end products (sRAGE) concentration >120.4 pg/ml were 0.25 times less likely to have ≥3 polyps relative to no polyps compared to males with sRAGE ≤94.5 pg/ml. For each increase in sRAGE tertile, a man was 0.5 times less likely to have ≥3 polyps than no polyps (p=0.03). Compared to males with a serum vascular endothelial growth factor (VEGF) concentration ≤104.7 pg/ml, males with a serum VEGF concentration >184.2 pg/ml were 3.4 times more likely to have ≥3 polyps relative to no polyps. As the VEGF tertile increased, a man was 1.9 times more likely to have ≥3 polyps than no polyps (p=0.049). Conclusions Serum concentrations of C-peptide, sRAGE, and VEGF may indicate which men could benefit most from colonoscopy. Impact Identification of biomarkers could reduce medical costs through the elimination of colonoscopies on low-risk individuals. PMID:24962837

  9. Crowdsourcing for identification of polyp-free segments in virtual colonoscopy videos

    NASA Astrophysics Data System (ADS)

    Park, Ji Hwan; Mirhosseini, Seyedkoosha; Nadeem, Saad; Marino, Joseph; Kaufman, Arie; Baker, Kevin; Barish, Matthew

    2017-03-01

    Virtual colonoscopy (VC) allows a physician to virtually navigate within a reconstructed 3D colon model searching for colorectal polyps. Though VC is widely recognized as a highly sensitive and specific test for identifying polyps, one limitation is the reading time, which can take over 30 minutes per patient. Large amounts of the colon are often devoid of polyps, and a way of identifying these polyp-free segments could be of valuable use in reducing the required reading time for the interrogating radiologist. To this end, we have tested the ability of the collective crowd intelligence of non-expert workers to identify polyp candidates and polyp-free regions. We presented twenty short videos flying through a segment of a virtual colon to each worker, and the crowd was asked to determine whether or not a possible polyp was observed within that video segment. We evaluated our framework on Amazon Mechanical Turk and found that the crowd was able to achieve a sensitivity of 80.0% and specificity of 86.5% in identifying video segments which contained a clinically proven polyp. Since each polyp appeared in multiple consecutive segments, all polyps were in fact identified. Using the crowd results as a first pass, 80% of the video segments could in theory be skipped by the radiologist, equating to a significant time savings and enabling more VC examinations to be performed.

  10. The use of real-time elastography in the assessment of gallbladder polyps: preliminary observations.

    PubMed

    Teber, Mehmet Akif; Tan, Sinan; Dönmez, Uğur; İpek, Ali; Uçar, Ali Erkan; Yıldırım, Halil; Aslan, Ahmet; Arslan, Halil

    2014-12-01

    Gallbladder polyps often have a benign nature. Current guidelines suggest surgical removal of polyps greater than 10 mm. However, the accuracy of the size criteria is limited because neoplasia can be found in gallbladder polyps less than 10 mm. The aim of this study was to evaluate the feasibility of real time elastography for gallbladder polyps and to demonstrate the elasticity properties of the polyps. Fifty-three polypoid lesions of the gallbladder were prospectively examined with real-time elastography. Of these patients, 52 had a diagnosis of benign gallbladder polyps and one patient was accepted as a gallbladder carcinoma due to its clinical and radiological findings. B-mode and real-time elastographic images were simultaneously presented as a two-panel image, and the elastogram was displayed in a color scale that ranged from red (greatest strain, softest component), to green (average strain, intermediate component), to blue (no strain, hardest component). The mean size for benign gallbladder polyps was 7.2 +/- 3 mm (range, 5-21 mm). All benign gallbladder polyps on consecutive real-time elastographic images appeared as having a high-strain elastographic pattern. Only one patient who was accepted with gallbladder carcinoma had a gallbladder polyp with low elasticity properties. Our study showed that real time elastography of gallbladder polyps is feasible. This novel approach may be useful for the characterization of polypoid lesions of the gallbladder.

  11. Predictive factors of neoplastic gallbladder polyps: Outcomes of 278 patients.

    PubMed

    Terzioğlu, Serdar Gökay; Kılıç, Murat Özgür; Sapmaz, Ali; Karaca, Ahmet Serdar

    2017-05-01

    Distinguishing between neoplastic and nonneoplastic gallbladder polyps (GBPs) in the preoperative workup is of great importance for appropriate treatment. The present study aimed to investigate the characteristics of GBPs and to determine potential predictive factors of neoplastic polyps. The data of 278 patients who were confirmed to have GBPs through laparoscopic cholecystectomy were retrospectively analyzed. Polyps were classified as nonneoplastic and neoplastic GBPs, according to histopathological diagnoses. All clinicopathological characteristics were compared between these two groups. There were 264 (95%) nonneoplastic GBPs and 14 (5%) neoplastic GBPs. In univariate analysis, there were significant differences in age with a cutoff value of 60 years (p=0.002), polyp size (p<0.001), number of polyps (p=0.014), and polyp morphology (p<0.001) between the groups. Multivariate analysis showed that solitary polyp (p<0.001) and sessile morphology (p<0.001) were the independent predictors of neoplastic GBPs. Receiver-operating characteristic curve analysis of three cut-off values of polyp sizes (6, 10, and 15 mm) indicated that a polyp size of 10 mm had the highest area under curve (0.942). Age above 60 years, solitary polyps larger than 1 cm, and sessile morphology are associated with an increased risk of neoplasia in GBP. Therefore, these characteristics should be considered in the management of GBPs to reduce the incidence of unnecessary surgeries and to prevent delays in the treatment of a possible cancer.

  12. A hitherto undescribed benign mesenchymal polyp of the gallbladder: edematous angiomyolipoma-like polyp.

    PubMed

    Arcega, R; Wu, J X; Magaki, S; Donahue, T R; Wang, H L

    2016-01-01

    We report a case of two peculiar gallbladder polyps in a sixty-four year old male who presented with symptomatic cholelithiasis. Cholecystectomy was performed, which revealed two polyps measuring 0.6 cm and 1.9 cm, located in the body of the gallbladder. Microscopic examination of the polyps showed composite mesenchymal lesions with vascular proliferation of small-to-medium sized arterioles, myoid stroma, and lipomatous periphery. The myoid component was characterized by wisps of bland smooth muscle fibers loosely separated by proteinaceous and focally myxoid matrix. The surface of the polyps was lined by a single layer of bland epithelial cells. The unique histomorphologic features differentiate the lesions from other known mesenchymal polyps of the gallbladder. We propose the name "edematous angiomyolipoma-like polyp" for these rare lesions given their histomorphologic similarity to angiomyolipoma. (Acta gastroenterol. belg., 2016, 79, 371-374). © Acta Gastro-Enterologica Belgica.

  13. The risk of malignancy in ultrasound detected gallbladder polyps: A systematic review.

    PubMed

    Elmasry, Mohamed; Lindop, Don; Dunne, Declan F J; Malik, Hassan; Poston, Graeme J; Fenwick, Stephen W

    2016-09-01

    Gallbladder polyps (GBPs) are a common incidental finding on ultrasound (US) examination. The malignant potential of GBPs is debated, and there is limited guidance on surveillance. This systematic review sought to assess the natural history of ultrasonographically diagnosed GBPs and their malignant potential. The keywords: "Gallbladder" AND ("polyp" OR "polypoid lesion") were used to conduct a search in four reference libraries to identify studies which examined the natural history of GBPs diagnosed by US. Twelve studies were eligible for inclusion in this review. Of the 5482 GBPs reported, malignant GBPs had an incidence of just 0.57%. True GBPs had an incidence of 0.60%. Sixty four patients of adenomatous and malignant polyps were reported. Only in one patient was a malignant GBP reported to be <6mm. Risk factors associated with increased risk of malignancy were GBP >6mm, single GBPs, symptomatic GBPs, age >60 years, Indian ethnicity, gallstones and cholecystitis. With the reported incidence of GBP malignancy at just 0.57%, a management approach based on risk assessment, clear surveillance planning, and multi disciplinary team (MDT) discussion should be adopted. The utilization of endoscopic ultrasound(EUS) should be Only considered on the grounds of its greater sensitivity and specificity when compared to US scans. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  14. Reproductive biology of the black coral Antipathella wollastoni (Cnidaria: Antipatharia) in the Azores (NE Atlantic)

    NASA Astrophysics Data System (ADS)

    Rakka, Maria; Orejas, Covadonga; Sampaio, Iris; Monteiro, João; Parra, Hugo; Carreiro-Silva, Marina

    2017-11-01

    Antipathella wollastoni is an antipatharian species common to Macaronesia, occurring in depths between 20 and 1425 m. Despite its importance as a habitat-forming species, there is no information about its basic biology. The aim of the current study is to describe its reproductive strategy, gametogenic cycle and reproductive timing. Sampling was performed monthly on six tagged colonies during one year and specimens were histologically processed. A. wollastoni was found to be a gonochoric broadcast spawner. Gametogenesis took place within the primary transversal mesenteries, and followed an annual cycle. The reproductive season coincided with an increase in seawater temperature but spawning, inferred from the disappearance of gametes, likely happened after the sea surface temperature peak of the year (September 2009). Polyp fecundity ranged from 1 to 309 oocytes/polyp. A decrease in polyp fecundity was detected in samples at the higher pre-spawning maturity stage, indicating possible repetitive spawning or oocyte absorption. Intra-colonial comparisons revealed a longer duration of the reproductive cycle in the medial colony section, and a gradient of increased oocyte size towards the apical section, possibly due to intra-colonial differences in energy allocation between reproduction and other biological processes, or as a strategy against predation on gametes/larvae. Colony height was positively correlated with polyp fecundity indicating that the reproductive output increases with colony size.

  15. Is it necessary to perform prophylactic cholecystectomy for asymptomatic subjects with gallbladder polyps and gallstones?

    PubMed

    Choi, Sung Youn; Kim, Tae Sun; Kim, Hong Joo; Park, Jung Ho; Park, Dong Il; Cho, Yong Kyun; Sohn, Chong Il; Jeon, Woo Kyu; Kim, Byung Ik

    2010-06-01

    The purpose of the present study was to determine the clinical characteristics of subjects with gallbladder polyps and cholelithiasis compared with those with gallbladder polyps only. Between August 1999 and December 2005, 176 subjects with gallbladder polyps and cholelithiasis (study group) by transabdominal ultrasonography performed during a medical check-up at our institution were recruited and compared with a control group of 185 subjects who had gallbladder polyps only. No significant difference in the mean interval change (delta) of polyp size during the follow-up period between the study and control groups (0.85 +/- 1.39 mm vs 0.84 +/- 1.58 mm, respectively, P = 0.927) was noted. A significantly higher proportion (9/176 [5.1%]) of examinees in the study group had attacks of acute cholecystitis compared with the control group (1/185 [0.5%], P < 0.01). By multivariate logistic regression analysis, gallbladder wall thickening on initial ultrasonography (odds ratio, 13.7; 95% confidence interval, 1.1-178.0; P = 0.046) and the interval increase in the size of the gallbladder polyps (odds ratio, 14.7; 95% confidence interval, 1.7-126.9; P = 0.014) were independent risk factors for cholecystectomy. No gallbladder cancer occurred during the follow-up period. There was no significant difference in delta polyp size between the examinees with gallbladder polyps and cholelithiasis and those with gallbladder polyps only. Hence, a small proportion of subjects with gallbladder polyps and cholelithiasis, such as those with thickened gallbladder walls and an interval increase in the size of the gallbladder polyps are candidates for prophylactic cholecytectomy.

  16. Impact of fair bowel preparation quality on adenoma and serrated polyp detection: data from the New Hampshire colonoscopy registry by using a standardized preparation-quality rating.

    PubMed

    Anderson, Joseph C; Butterly, Lynn F; Robinson, Christina M; Goodrich, Martha; Weiss, Julia E

    2014-09-01

    The effect of colon preparation quality on adenoma detection rates (ADRs) is unclear, partly because of lack of uniform colon preparation ratings in prior studies. The New Hampshire Colonoscopy Registry collects detailed data from colonoscopies statewide, by using a uniform preparation quality scale after the endoscopist has cleaned the mucosa. To compare the overall and proximal ADR and serrated polyp detection rates (SDR) in colonoscopies with differing levels of colon preparation quality. Cross-sectional. New Hampshire statewide registry. Patients undergoing colonoscopy. We examined colon preparation quality for 13,022 colonoscopies, graded by using specific descriptions provided to endoscopists. ADR and SDR are the number of colonoscopies with at least 1 adenoma or serrated polyp (excluding those in the rectum and/or sigmoid colon) detected divided by the total number of colonoscopies, for the preparation categories: optimal (excellent and/or good), fair, and poor. Overall/proximal ADR/SDR. The overall detection rates in examinations with fair colon preparation quality (SDR 8.9%; 95% confidence interval [CI], 7.4-10.7, ADR 27.1%; 95% CI, 24.6-30.0) were similar to rates observed in colonoscopies with optimal preparation quality (SDR 8.8%; 95% CI, 8.3-9.4, ADR 26.3%; 95% CI, 25.6-27.2). This finding also was observed for rates in the proximal colon. A logistic regression model (including withdrawal time) found that proximal ADR was statistically lower in the poor preparation category (odds ratio 0.45; 95% CI, 0.24-0.84; P < .01) than in adequately prepared colons. Homogeneous population. In our sample, there was no significant difference in overall or proximal ADR or SDR between colonoscopies with fair versus optimal colon preparation quality. Poor colon preparation quality may reduce the proximal ADR. Published by Mosby, Inc.

  17. [Experience of Fusion image guided system in endonasal endoscopic surgery].

    PubMed

    Wen, Jingying; Zhen, Hongtao; Shi, Lili; Cao, Pingping; Cui, Yonghua

    2015-08-01

    To review endonasal endoscopic surgeries aided by Fusion image guided system, and to explore the application value of Fusion image guided system in endonasal endoscopic surgeries. Retrospective research. Sixty cases of endonasal endoscopic surgeries aided by Fusion image guided system were analysed including chronic rhinosinusitis with polyp (n = 10), fungus sinusitis (n = 5), endoscopic optic nerve decompression (n = 16), inverted papilloma of the paranasal sinus (n = 9), ossifying fibroma of sphenoid bone (n = 1), malignance of the paranasal sinus (n = 9), cerebrospinal fluid leak (n = 5), hemangioma of orbital apex (n = 2) and orbital reconstruction (n = 3). Sixty cases of endonasal endoscopic surgeries completed successfully without any complications. Fusion image guided system can help to identify the ostium of paranasal sinus, lamina papyracea and skull base. Fused CT-CTA images, or fused MR-MRA images can help to localize the optic nerve or internal carotid arteiy . Fused CT-MR images can help to detect the range of the tumor. It spent (7.13 ± 1.358) minutes for image guided system to do preoperative preparation and the surgical navigation accuracy reached less than 1mm after proficient. There was no device localization problem because of block or head set loosed. Fusion image guided system make endonasal endoscopic surgery to be a true microinvasive and exact surgery. It spends less preoperative preparation time, has high surgical navigation accuracy, improves the surgical safety and reduces the surgical complications.

  18. Linked color imaging improves the visibility of colorectal polyps: a video study

    PubMed Central

    Yoshida, Naohisa; Naito, Yuji; Murakami, Takaaki; Hirose, Ryohei; Ogiso, Kiyoshi; Inada, Yutaka; Dohi, Osamu; Kamada, Kazuhiro; Uchiyama, Kazuhiko; Handa, Osamu; Konishi, Hideyuki; Siah, Kewin Tien Ho; Yagi, Nobuaki; Fujita, Yasuko; Kishimoto, Mitsuo; Yanagisawa, Akio; Itoh, Yoshito

    2017-01-01

    Background/study aim  Linked color imaging (LCI) by a laser endoscope (Fujifilm Co, Tokyo, Japan) is a novel narrow band light observation. In this study, we aimed to investigate whether LCI could improve the visibility of colorectal polyps using endoscopic videos. Patients and methods  We prospectively recorded videos of consecutive polyps 2 – 20 mm in size diagnosed as neoplastic polyps. Three videos, white light (WL), blue laser imaging (BLI)-bright, and LCI, were recorded for each polyp by one expert. After excluding inappropriate videos, all videos were evaluated in random order by two experts and two non-experts according to a published polyp visibility score from four (excellent visibility) to one (poor visibility). Additionally, the relationship between polyp visibility scores in LCI and various clinical characteristics including location, size, histology, morphology, and preparation were analyzed compared to WL and BLI-bright. Results  We analyzed 101 colorectal polyps (94 neoplastic) in 66 patients (303 videos). The mean polyp size was 9.0 ± 8.1 mm and 54 polyps were non-polypoid. The mean polyp visibility scores for LCI (2.86 ± 1.08) were significantly higher than for WL and BLI-bright (2.53 ± 1.15, P  < 0.001; 2.73 ± 1.47, P  < 0.041). The ratio of poor visibility (score 1 and 2) was significantly lower in LCI for experts and non-experts (35.6 %, 33.6 %) compared with WL (49.6 %, P  = 0.015, 50.5 %, P  = 0.046). The polyp visibility scores for LCI were significantly higher than those for WL for all of the factors. With respect to the comparison between BLI-bright and WL, the polyp visibility scores for BLI-bright were not higher than WL for right-sided location, < 10 mm size, sessile serrated adenoma and polyp histology, and poor preparation. For those characteristics, LCI improved the lesions with right-sided location, SSA/P histology, and poor preparation significantly better than BLI. Conclusions  LCI improved polyp visibility compared to WL for both expert and non-expert endoscopists. It is useful for improving polyp visibility in any location, any size, any morphology, any histology, and any preparation level. PMID:28596985

  19. Polypoid lesions of the gallbladder: disease spectrum with pathologic correlation.

    PubMed

    Mellnick, Vincent M; Menias, Christine O; Sandrasegaran, Kumar; Hara, Amy K; Kielar, Ania Z; Brunt, Elizabeth M; Doyle, Maria B Majella; Dahiya, Nirvikar; Elsayes, Khaled M

    2015-01-01

    Gallbladder polyps are seen on as many as 7% of gallbladder ultrasonographic images. The differential diagnosis for a polypoid gallbladder mass is wide and includes pseudotumors, as well as benign and malignant tumors. Tumefactive sludge may be mistaken for a gallbladder polyp. Pseudotumors include cholesterol polyps, adenomyomatosis, and inflammatory polyps, and they occur in that order of frequency. The most common benign and malignant tumors are adenomas and primary adenocarcinoma, respectively. Polyp size, shape, and other ancillary imaging findings, such as a wide base, wall thickening, and coexistent gallstones, are pertinent items to report when gallbladder polyps are discovered. These findings, as well as patient age and risk factors for gallbladder cancer, guide clinical decision making. Symptomatic polyps without other cause for symptoms, an age over 50 years, and the presence of gallstones are generally considered indications for cholecystectomy. Incidentally noted pedunculated polyps smaller than 5 mm generally do not require follow-up. Polyps that are 6-10 mm require follow-up, although neither the frequency nor the length of follow-up has been established. Polyps that are larger than 10 mm are typically excised, although lower size thresholds for cholecystectomy may be considered for patients with increased risk for gallbladder carcinoma, such as patients with primary sclerosing cholangitis. (©)RSNA, 2015.

  20. Developmental accumulation of inorganic polyphosphate affects germination and energetic metabolism in Dictyostelium discoideum

    PubMed Central

    Livermore, Thomas Miles; Chubb, Jonathan Robert; Saiardi, Adolfo

    2016-01-01

    Inorganic polyphosphate (polyP) is composed of linear chains of phosphate groups linked by high-energy phosphoanhydride bonds. However, this simple, ubiquitous molecule remains poorly understood. The use of nonstandardized analytical methods has contributed to this lack of clarity. By using improved polyacrylamide gel electrophoresis we were able to visualize polyP extracted from Dictyostelium discoideum. We established that polyP is undetectable in cells lacking the polyphosphate kinase (DdPpk1). Generation of this ppk1 null strain revealed that polyP is important for the general fitness of the amoebae with the mutant strain displaying a substantial growth defect. We discovered an unprecedented accumulation of polyP during the developmental program, with polyP increasing more than 100-fold. The failure of ppk1 spores to accumulate polyP results in a germination defect. These phenotypes are underpinned by the ability of polyP to regulate basic energetic metabolism, demonstrated by a 2.5-fold decrease in the level of ATP in vegetative ppk1. Finally, the lack of polyP during the development of ppk1 mutant cells is partially offset by an increase of both ATP and inositol pyrophosphates, evidence for a model in which there is a functional interplay between inositol pyrophosphates, ATP, and polyP. PMID:26755590

  1. Detection of colorectal masses in CT colonography: application of deep residual networks for differentiating masses from normal colon anatomy

    NASA Astrophysics Data System (ADS)

    Näppi, Janne J.; Hironaka, Toru; Yoshida, Hiroyuki

    2018-02-01

    Even though the clinical consequences of a missed colorectal cancer far outweigh those of a missed polyp, there has been little work on computer-aided detection (CADe) for colorectal masses in CT colonography (CTC). One of the problems is that it is not clear how to manually design mathematical image-based features that could be used to differentiate effectively between masses and certain types of normal colon anatomy such as ileocecal valves (ICVs). Deep learning has demonstrated ability to automatically determine effective discriminating features in many image-based problems. Recently, residual networks (ResNets) were developed to address the practical problems of constructing deep network architectures for optimizing the performance of deep learning. In this pilot study, we compared the classification performance of a conventional 2D-convolutional ResNet (2D-ResNet) with that of a volumetric 3D-convolutional ResNet (3D-ResNet) in differentiating masses from normal colon anatomy in CTC. For the development and evaluation of the ResNets, 695 volumetric images of biopsy-proven colorectal masses, ICVs, haustral folds, and rectal tubes were sampled from 196 clinical CTC cases and divided randomly into independent training, validation, and test datasets. The training set was expanded by use of volumetric data augmentation. Our preliminary results on the 140 test samples indicate that it is feasible to train a deep volumetric 3D-ResNet for performing effective image-based discriminations in CTC. The 3D-ResNet slightly outperformed the 2D-ResNet in the discrimination of masses and normal colon anatomy, but the statistical difference between their very high classification accuracies was not significant. The highest classification accuracy was obtained by combining the mass-likelihood estimates of the 2D- and 3D-ResNets, which enabled correct classification of all of the masses.

  2. Computer-aided diagnosis workstation and network system for chest diagnosis based on multislice CT images

    NASA Astrophysics Data System (ADS)

    Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Moriyama, Noriyuki; Ohmatsu, Hironobu; Masuda, Hideo; Machida, Suguru

    2008-03-01

    Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. To overcome this problem, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images, a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification and a vertebra body analysis algorithm for quantitative evaluation of osteoporosis likelihood by using helical CT scanner for the lung cancer mass screening. The function to observe suspicious shadow in detail are provided in computer-aided diagnosis workstation with these screening algorithms. We also have developed the telemedicine network by using Web medical image conference system with the security improvement of images transmission, Biometric fingerprint authentication system and Biometric face authentication system. Biometric face authentication used on site of telemedicine makes "Encryption of file" and Success in login" effective. As a result, patients' private information is protected. Based on these diagnostic assistance methods, we have developed a new computer-aided workstation and a new telemedicine network that can display suspected lesions three-dimensionally in a short time. The results of this study indicate that our radiological information system without film by using computer-aided diagnosis workstation and our telemedicine network system can increase diagnostic speed, diagnostic accuracy and security improvement of medical information.

  3. Associations among Pericolonic Fat, Visceral Fat, and Colorectal Polyps on CT Colonography

    PubMed Central

    Liu, Jiamin; Pattanaik, Sanket; Yao, Jianhua; Dwyer, Andrew J.; Pickhardt, Perry J.; Choi, J. Richard; Summers, Ronald M.

    2014-01-01

    OBJECTIVE To determine the association between pericolonic fat and colorectal polyps using CT colonography (CTC). METHODS 1169 patients who underwent CTC and same day optical colonoscopy were assessed. Pericolonic fat was measured on CTC in a band surrounding the colon. Visceral adipose tissue volume was measured at the L2-L3 levels. Student t-tests, odds ratio, logistic regression, binomial statistics and weighted-kappa were performed to ascertain associations with the incidence of colorectal polyps. RESULTS Pericolonic fat volume fractions (PFVF) were 61.5±11.0% versus 58.1±11.5%, 61.6 ±11.1% versus 58.7±11.5%, and 62.4±10.6% versus 58.8±11.5% for patients with and without any polyps, adenomatous polyps, and hyperplastic polyps, respectively (p<0.0001). Similar trends were observed when examining visceral fat volume fractions (VFVF). When patients were ordered by quintiles of PFVF or VFVF, there were 2.49, 2.19 and 2.39-fold increases in odds ratio for the presence of any polyp, adenomatous polyps, or hyperplastic polyps from the first to the fifth quintile for PFVF, and 1.92, 2.00 and 1.71-fold increases in odds ratio for VFVF. Polyps tended to occur more commonly in parts of the colon that had more PFVF than the spatially-adjusted average for patients in the highest quintile of VFVF. CONCLUSION Pericolonic fat accumulations, like visceral fat, are correlated with an increased risk of adenomatous and hyperplastic polyps. PMID:25558027

  4. "Difficult" Colorectal Polyps - Therapeutic Approach.

    PubMed

    Alecu, M; Simion, L; Ionescu, S; Brătucu, E; Straja, N D

    2015-01-01

    Endoscopic polypectomy is the gold standard in the treatment of colorectal polyps. The importance of polypectomy rests primarily on the fact that polyp-type lesions present a high risk of malignant degeneration, colorectal polyps being able, if left unattended therapeutically, to generate a colorectal cancer (CRC) - a lesion with a far more negative prognosis. Although preferable, endoscopic polypectomy of colorectal polyps is not always possible, multiple factors generating difficulties in performing this therapeutic measure. We performed a retrospective study in the First Surgical Clinic of the "Prof. Dr. Alexandu Trestioreanu" Bucharest Oncology Institute, spanning a period of 3 years (2008-2011), in which time 224 patients were diagnosed by colonoscopy with colorectal polyps, of whom 222 patients benefited from endoscopic polypectomy. The aim of the study was to identify "difficult" polyps and to identify the criteria for endoscopic surgery versus classic surgery as a therapeutic indication. Presence of "difficult" polyps was observed in 37.56% of the patients diagnosed with colorectal polyps. In over 88% of cases endoscopic polypectomy was possible, and for the remaining patients classic surgery was the therapeutic solution opted for. Presence of "difficult" polyps generates inconveniences in performing endoscopic polypectomy, increasing the risk of postoperative complication occurrence, as well as the duration of the operation. If the criteria for characterizing polyps as "difficult" are relatively well-established, the choice between endoscopic and classic surgery as a therapeutic measure is left at the free will of the operating surgeon, with the exception of situations in which classic surgery is resorted to for oncological reasons. Celsius.

  5. Prospective randomized comparison of cold snare polypectomy and conventional polypectomy for small colorectal polyps.

    PubMed

    Ichise, Yasuyuki; Horiuchi, Akira; Nakayama, Yoshiko; Tanaka, Naoki

    2011-01-01

    The ideal method to remove small colorectal polyps is unknown. We compared removal by colon snare transection without electrocautery (cold snare polypectomy) with conventional electrocautery snare polypectomy (hot polypectomy) in terms of procedure duration, difficulty in retrieving polyps, bleeding, and post-polypectomy symptoms. Patients with colorectal polyps up to 8 mm in diameter were randomized to polypectomy by cold snare technique (cold group) or conventional polypectomy (conventional group). The principal outcome measures were abdominal symptoms within 2 weeks after polypectomy. Secondary outcome measures were the rates of retrieval of colorectal polyps and bleeding. Eighty patients were randomized: cold group, n = 40 (101 polyps) and conventional group, n = 40 (104 polyps). The patients' demographic characteristics and the number and size of polyps removed were similar between the two techniques. Procedure time was significantly shorter with cold polypectomy vs. conventional polypectomy (18 vs. 25 min, p < 0.0001). Complete polyp retrieval rates were identical [96% (97/101) vs. 96% (100/104)]. No bleeding requiring hemostasis occurred in either group. Abdominal symptoms shortly after polypectomy were more common with conventional polypectomy (i.e. 20%; 8/40) than with cold polypectomy (i.e. 2.5%; 1/40; p = 0.029). Cold polypectomy was superior to conventional polypectomy in terms of procedure time and post-polypectomy abdominal symptoms. The two methods were otherwise essentially identical in terms of bleeding risk and complete polyp retrieval. Cold polypectomy is therefore the preferred method for removal of small colorectal polyps. Copyright © 2011 S. Karger AG, Basel.

  6. Variation in polyp size estimation among endoscopists and impact on surveillance intervals.

    PubMed

    Chaptini, Louis; Chaaya, Adib; Depalma, Fedele; Hunter, Krystal; Peikin, Steven; Laine, Loren

    2014-10-01

    Accurate estimation of polyp size is important because it is used to determine the surveillance interval after polypectomy. To evaluate the variation and accuracy in polyp size estimation among endoscopists and the impact on surveillance intervals after polypectomy. Web-based survey. A total of 873 members of the American Society for Gastrointestinal Endoscopy. Participants watched video recordings of 4 polypectomies and were asked to estimate the polyp sizes. Proportion of participants with polyp size estimates within 20% of the correct measurement and the frequency of incorrect surveillance intervals based on inaccurate size estimates. Polyp size estimates were within 20% of the correct value for 1362 (48%) of 2812 estimates (range 39%-59% for the 4 polyps). Polyp size was overestimated by >20% in 889 estimates (32%, range 15%-49%) and underestimated by >20% in 561 (20%, range 4%-46%) estimates. Incorrect surveillance intervals because of overestimation or underestimation occurred in 272 (10%) of the 2812 estimates (range 5%-14%). Participants in a private practice setting overestimated the size of 3 or of all 4 polyps by >20% more often than participants in an academic setting (difference = 7%; 95% confidence interval, 1%-11%). Survey design with the use of video clips. Substantial overestimation and underestimation of polyp size occurs with visual estimation leading to incorrect surveillance intervals in 10% of cases. Our findings support routine use of measurement tools to improve polyp size estimates. Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  7. Observer training for computer-aided detection of pulmonary nodules in chest radiography.

    PubMed

    De Boo, Diederick W; van Hoorn, François; van Schuppen, Joost; Schijf, Laura; Scheerder, Maeke J; Freling, Nicole J; Mets, Onno; Weber, Michael; Schaefer-Prokop, Cornelia M

    2012-08-01

    To assess whether short-term feedback helps readers to increase their performance using computer-aided detection (CAD) for nodule detection in chest radiography. The 140 CXRs (56 with a solitary CT-proven nodules and 84 negative controls) were divided into four subsets of 35; each were read in a different order by six readers. Lesion presence, location and diagnostic confidence were scored without and with CAD (IQQA-Chest, EDDA Technology) as second reader. Readers received individual feedback after each subset. Sensitivity, specificity and area under the receiver-operating characteristics curve (AUC) were calculated for readings with and without CAD with respect to change over time and impact of CAD. CAD stand-alone sensitivity was 59 % with 1.9 false-positives per image. Mean AUC slightly increased over time with and without CAD (0.78 vs. 0.84 with and 0.76 vs. 0.82 without CAD) but differences did not reach significance. The sensitivity increased (65 % vs. 70 % and 66 % vs. 70 %) and specificity decreased over time (79 % vs. 74 % and 80 % vs. 77 %) but no significant impact of CAD was found. Short-term feedback does not increase the ability of readers to differentiate true- from false-positive candidate lesions and to use CAD more effectively. • Computer-aided detection (CAD) is increasingly used as an adjunct for many radiological techniques. • Short-term feedback does not improve reader performance with CAD in chest radiography. • Differentiation between true- and false-positive CAD for low conspicious possible lesions proves difficult. • CAD can potentially increase reader performance for nodule detection in chest radiography.

  8. Specialist Endoscopists Are Associated with a Decreased Risk of Incomplete Polyp Resection During Endoscopic Mucosal Resection in the Colon.

    PubMed

    Tavakkoli, Anna; Law, Ryan J; Bedi, Aarti O; Prabhu, Anoop; Hiatt, Tadd; Anderson, Michelle A; Wamsteker, Erik J; Elmunzer, B Joseph; Piraka, Cyrus R; Scheiman, James M; Elta, Grace H; Kwon, Richard S

    2017-09-01

    Endoscopic experience is known to correlate with outcomes of endoscopic mucosal resection (EMR), particularly complete resection of the polyp tissue. Whether specialist endoscopists can protect against incomplete polypectomy in the setting of known risk factors for incomplete resection (IR) is unknown. We aimed to characterize how specialist endoscopists may help to mitigate the risk of IR of large sessile polyps. This is a retrospective cohort study of patients who underwent EMR at the University of Michigan from January 1, 2006, to November 15, 2015. The primary outcome was endoscopist-reported polyp tissue remaining at the end of the initial EMR attempt. Specialist endoscopists were defined as endoscopists who receive tertiary referrals for difficult colonoscopy cases and completed at least 20 EMR colonic polyp resections over the study period. A total of 257 patients with 269 polyps were included in the study. IR occurred in 40 (16%) cases. IR was associated with polyp size ≥ 40 mm [adjusted odds ratio (aOR) 3.31, 95% confidence interval (CI) 1.38-7.93], flat/laterally spreading polyps (aOR 2.61, 95% CI 1.24-5.48), and difficulty lifting the polyp (aOR 11.0, 95% CI 2.66-45.3). A specialist endoscopist performing the initial EMR was protective against IR, even in the setting of risk factors for IR (aOR 0.13, 95% CI 0.04-0.41). IR is associated with polyp size ≥ 40 mm, flat and/or laterally spreading polyps, and difficulty lifting the polyp. A specialist endoscopist initiating the EMR was protective of IR.

  9. Diagnostic accuracy of transabdominal ultrasonography for gallbladder polyps: systematic review.

    PubMed

    Martin, Erin; Gill, Richdeep; Debru, Estifanos

    2018-06-01

    Previous research has shown variable but generally poor accuracy of transabdominal ultrasonography in the diagnosis of gallbladder polyps. We performed a systematic review of the literature with the aim of helping surgeons interpret and apply these findings in the preoperative assessment and counselling of their patients. We searched PubMed, MEDLINE and the Cochrane database using the keywords "gallbladder," "polyp," "ultrasound," "pathology" and "diagnosis" for English-language articles published after 1990 with the full-text article available through our institutional subscriptions. Polyps were defined as immobile features that on transabdominal ultrasonography appear to arise from the mucosa and that lack an acoustic shadow, and pseudopolyps were defined as features such as inflammation, hyperplasia, cholesterolosis and adenomyomatosis that convey no risk of malignant transformation. The search returned 1816 articles, which were narrowed down to 14 primary sources involving 15 497 (range 23-13 703) patients who had preoperative transabdominal ultrasonography, underwent cholecystectomy and had postoperative pathology results available. Among the 1259 patients in whom a gallbladder polyp was diagnosed on ultrasonography, 188 polyps were confirmed as true polyps on pathologic examination, and 81 of these were found to be malignant. Of the 14 238 patients for whom a polyp was not seen on ultrasonography, 38 had a true polyp on pathologic examination, none of which were malignant. For true gallbladder polyps, transabdominal ultrasonography had a sensitivity of 83.1%, specificity of 96.3%, positive predictive value of 14.9% (7.0% for malignant polyps) and negative predictive value of 99.7%. Transabdominal ultrasonography has a high false-positive rate (85.1%) for the diagnosis of gallbladder polyps. Further study of alternative imaging modalities and reevaluation of existing management guidelines are warranted.

  10. Discrimination of premalignant lesions and cancer tissues from normal gastric tissues using Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Luo, Shuwen; Chen, Changshui; Mao, Hua; Jin, Shaoqin

    2013-06-01

    The feasibility of early detection of gastric cancer using near-infrared (NIR) Raman spectroscopy (RS) by distinguishing premalignant lesions (adenomatous polyp, n=27) and cancer tissues (adenocarcinoma, n=33) from normal gastric tissues (n=45) is evaluated. Significant differences in Raman spectra are observed among the normal, adenomatous polyp, and adenocarcinoma gastric tissues at 936, 1003, 1032, 1174, 1208, 1323, 1335, 1450, and 1655 cm-1. Diverse statistical methods are employed to develop effective diagnostic algorithms for classifying the Raman spectra of different types of ex vivo gastric tissues, including principal component analysis (PCA), linear discriminant analysis (LDA), and naive Bayesian classifier (NBC) techniques. Compared with PCA-LDA algorithms, PCA-NBC techniques together with leave-one-out, cross-validation method provide better discriminative results of normal, adenomatous polyp, and adenocarcinoma gastric tissues, resulting in superior sensitivities of 96.3%, 96.9%, and 96.9%, and specificities of 93%, 100%, and 95.2%, respectively. Therefore, NIR RS associated with multivariate statistical algorithms has the potential for early diagnosis of gastric premalignant lesions and cancer tissues in molecular level.

  11. The effects of different restorative materials on the detection of approximal caries in cone-beam computed tomography scans with and without metal artifact reduction mode.

    PubMed

    Cebe, Fatma; Aktan, Ali Murat; Ozsevik, Abdul Semih; Ciftci, Mehmet Ertugrul; Surmelioglu, Hatice Derya

    2017-03-01

    The aim of this study was to investigate the influence of artifacts produced by different restorative materials on the detection of approximal caries in cone-beam computed tomography (CBCT) scans with and without the application of an artifact-reduction (AR) option. Ninety-eight noncavitated premolar and molar teeth were placed with approximal contacts consisting of 2 sound or carious teeth and 1 mesial-occlusal-distal restored tooth with resin-modified glass-ionomer cement (RMGIC), amalgam, composite, ceramic-based composite (CBC), or computer-aided design-computer-aided manufacturing (CAD-CAM) zirconia materials in between. The teeth were scanned with a CBCT system with and without the AR option. Images were evaluated by 2 observers. The teeth were histologically evaluated, and sensitivity, specificity, and areas under the receiver operating characteristic (ROC) curve were calculated according to the appropriate threshold. Specificity and sensitivity values for contact surfaces ranged from 0-48.39 and 82.93-98.40, respectively. The AR option affected (P < .05) approximal caries detection of the amalgam, composite, CAD-CAM, and CBC groups in contact surfaces and composite and RMGIC groups in noncontact surfaces. Artifacts produced by different restorative materials could affect approximal caries detection in CBCT scans. Use of the AR option with CBCT scans increases the accuracy of approximal caries detection. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Histological variations in juvenile polyp phenotype correlate with genetic defect underlying juvenile polyposis

    PubMed Central

    van Hattem, W. Arnout; Langeveld, Danielle; de Leng, Wendy W. J.; Morsink, Folkert H.; van Diest, Paul J.; Iacobuzio-Donahue, Christine A.; Giardiello, Francis M.; Offerhaus, G. Johan A.; Brosens, Lodewijk A. A.

    2011-01-01

    Background Juvenile polyps are distinct hamartomatous malformations of the gastrointestinal tract that may occur in the heritable juvenile polyposis syndrome (JPS) or sporadically. Histologically, juvenile polyps are characterised by a marked increase of the stromal cell compartment but, an epithelial phenotype has also been reported. JPS has an increased risk of colorectal cancer but sporadic juvenile polyps do not. In 50–60% of JPS patients a germline mutation of the TGF-β/BMP pathway genes SMAD4 or BMPR1A is found. This study compares the histological phenotype of juvenile polyps with a SMAD4 or BMPR1A germline mutation and sporadic juvenile polyps. Methods H&E slides of 65 JPS polyps and 25 sporadic juvenile polyps were reviewed for histological features and dysplasia. Systematic random crypt and stroma counts were obtained by count stereology and a crypt-stroma ratio was determined. All polyps were subsequently categorised as type A (crypt-stroma ratio <1.00) or type B (crypt-stroma ratio ≥1.00), the latter referring to the epithelial phenotype. Cell cycle activity was assessed using immunohistochemistry of the proliferation marker Ki67, and mutation analysis was conducted for KRAS and APC to determine the involvement of the adenoma-carcinoma sequence. Results Juvenile polyps with a SMAD4 germline mutation were predominantly type B, whereas, type A was more common among juvenile polyps with a BMPR1A germline mutation, but this distinction could not be ascribed to differences in cell cycle activity. Dysplasia was equally common in JPS polyps with either a SMAD4 or BMPR1A germline mutation, where the involvement of the adenoma-carcinoma sequence does not seem to play a distinct role. Conclusion juvenile polyps in the setting of JPS exhibit distinct phenotypes correlating with the underlying genetic defect. PMID:21412070

  13. Clinical Significance of Colonoscopy in Patients with Upper Gastrointestinal Polyps and Neoplasms: A Meta-Analysis

    PubMed Central

    Wu, Zhen-Jie; Lin, Yuan; Xiao, Jun; Wu, Liu-Cheng; Liu, Jun-Gang

    2014-01-01

    Background Some authors have studied the relationship between the presence of polyps, adenomas and cancers of upper gastrointestinal tract (stomach and duodenum) and risk of colorectal polyps and neoplasms; however, the results are controversial, which may be due to study sample size, populations, design, clinical features, and so on. No meta-analysis, which can be generalized to a larger population and could provide a quantitative pooled risk estimate of the relationship, of this issue existed so far. Methods We performed a meta-analysis to evaluate risk of colorectal polyps or neoplasms in patients with polyps, adenomas or cancers in upper gastrointestinal tract comparing with controls. A search was conducted through PubMed, EMBASE, reference lists of potentially relevant papers, and practice guidelines up to 27 November 2013 without languages restriction. Odd ratios (ORs) were pooled using random-effects models. Results The search yielded 3 prospective and 21 retrospective case-control studies (n = 37152 participants). The principal findings included: (1) OR for colorectal polyps was 1.15 (95% CI, 1.04–1.26) in the gastric polyps group comparing with control groups; (2) Patients with gastric polyps and neoplasms have higher risk (OR, 1.31 [95% CI, 1.06–1.62], and 1.72 [95% CI, 1.42–2.09], respectively) of colorectal neoplasms comparing with their controls; and (3) Positive association was found between the presence of colorectal neoplasms and sporadic duodenal neoplasms (OR, 2.59; 95% CI, 1.64–4.11). Conclusions Findings from present meta-analysis of 24 case-control studies suggest that the prevalence of colorectal polyps was higher in patients with gastric polyps than in those without gastric polyps, and the risk of colorectal neoplasms increases significantly in patients with gastric polyps, neoplasms, and duodenal neoplasms. Therefore, screening colonoscopy should be considered for patients with upper gastrointestinal polyps and neoplasms. PMID:24637723

  14. Metamorphosis and acquisition of symbiotic algae in planula larvae and primary polyps of Acropora spp.

    NASA Astrophysics Data System (ADS)

    Hirose, M.; Yamamoto, H.; Nonaka, M.

    2008-06-01

    Coral planulae settle, then metamorphose and form polyps. This study examined the morphological process of metamorphosis from planulae into primary polyps in the scleractinian corals Acropora nobilis and Acropora microphthalma, using the cnidarian neuropeptide Hym-248 . These two species release eggs that do not contain Symbiodinium. The mode of acquisition of freshly isolated Symbiodinium (zooxanthellae) (FIZ) by the non-symbiotic polyp was also examined. Non-Hym-248 treated swimming Acropora planulae did not develop blastopore, mesenteries or coelenteron until the induction of metamorphosis 16 days after fertilization. The oral pore was formed by invagination of the epidermal layer after formation of the coelenteron in metamorphosing polyps. At 3 days after settlement and metamorphosis, primary polyps exposed to FIZ established symbioses with the Symbiodinium. Two-four days after exposure to FIZ, the distribution of Symbiodinium was limited to the gastrodermis of the pharynx and basal part of the polyps. Eight-ten days after exposure to FIZ, Symbiodinium were present in gastrodermal cells throughout the polyps.

  15. Differential diagnosis between gallbladder adenomas and cholesterol polyps on contrast-enhanced harmonic endoscopic ultrasonography.

    PubMed

    Park, Chan Hyuk; Chung, Moon Jae; Oh, Tak Geun; Park, Jeong Youp; Bang, Seungmin; Park, Seung Woo; Kim, Hyunki; Hwang, Ho Kyoung; Lee, Woo Jung; Song, Si Young

    2013-04-01

    Differential diagnosis between gallbladder (GB) adenomas and cholesterol polyps based on ultrasonography or endoscopic ultrasonography (EUS) is challenging because they have similar echogenicity and morphology. We evaluated the usefulness of contrast-enhanced harmonic EUS (CEH-EUS) for differentiating between GB adenomas and cholesterol polyps. Between June 2010 and December 2011, a total of 87 patients with GB polyps who underwent a CEH-EUS were reviewed retrospectively. Of the 87 patients, 57 had a cholecystectomy. Of these, 34 patients were diagnosed with adenoma, cholesterol polyp, adenocarcinoma, or adenomyomatosis pathology. The remaining 23 patients were not diagnosed with GB polyps because their lesions separated from the GB mucosal layer during pathological sampling. On CEH-EUS, homogeneous and heterogeneous enhancement was shown in 6 and 2 patients with adenoma and in 4 and 8 patients with cholesterol polyps, respectively. Sensitivity and specificity of CEH-EUS for differential diagnosis of GB adenomas from cholesterol polyps based on the enhancement pattern were 75.0 and 66.6 %, respectively. CEH-EUS might be useful for distinguishing GB adenomas and cholesterol polyps based on enhancement patterns. However, an additional technique such as quantitative perfusion analysis is necessary because visual assessment of CEH-EUS images is subjective.

  16. Endoscopic follow-up of 383 patients with colorectal adenoma: an observational study in daily practice.

    PubMed

    Jonkers, Daisy; Ernst, Justi; Pladdet, Ingrid; Stockbrügger, Reinhold; Hameeteman, Wim

    2006-06-01

    Endoscopic removal of colorectal adenomas reduces the incidence and mortality of colorectal cancer (CRC), but follow-up surveillance is recommended. Compliance with the Dutch surveillance guidelines and detection of neoplasia during follow-up has been evaluated in daily practice. From 1987 to 1996, 383 consecutive patients with colorectal adenomas (56.4% male, 61.8+/-11.3 years) were included and followed until December 2000. The mean follow-up was 80.5+/-42.5 months with 2.2+/-0.9 follow-up endoscopies. A total of 32.5 and 27.3% of follow-up endoscopies were performed >25% (time between advised and actual endoscopy) too late or too early, respectively. At the end of follow-up, 33.4% of patients had left the follow-up (two-thirds died) and 60.1% were known with co-morbidity. A first, second, third, fourth and fifth follow-up endoscopy had been performed in 327, 238, 132, 64 and 35 patients, respectively. Adenomatous polyps (with high-risk polyps) were detected in 100% (42.6%) of the index endoscopies and in 25.1% (17.4%), 23.9% (10.5%), 28.0% (12.1%), 34.4% (25.0%) and 37.1% (17.1%) of the first to fifth follow-up endoscopy, respectively. CRC was diagnosed in seven patients (46.1+/-22.9 months after index endoscopy), resulting in a standardized incidence ratio of 1.4 (confidence interval 0.6-3.0, P=0.4) compared to the general population. In this daily practice, high numbers of total and high-risk adenomatous polyps were found during follow-up surveillance. The incidence of CRC was not significantly different from the general population, which might be due to the intensive follow-up and removal of polyps. These findings support the importance of follow-up surveillance. However, the high overall morbidity and mortality should be taken into account when selecting patients for an intensive follow-up programme.

  17. Associations of dietary fat with risk of early neoplasia in the proximal colon in a population-based case-control study.

    PubMed

    Mo, Allen; Wu, Rong; Grady, James P; Hanley, Matthew P; Toro, Margaret; Swede, Helen; Devers, Thomas J; Hartman, Terryl J; Rosenberg, Daniel W

    2018-07-01

    Excess dietary fat consumption is strongly associated with the risk of colorectal cancer, but less is known about its role in the earliest stages of carcinogenesis, particularly within the proximal colon. In the following case-control study, we evaluated the relationship between the intake of dietary fats and the frequency of early proximal neoplasia [aberrant crypt foci (ACF) or polyps], detectable by high-definition colonoscopy with contrast dye-spray. Average-risk screening individuals underwent a high-definition colonoscopy procedure as part of larger ongoing clinical study of precancerous lesions in the proximal colon. Dietary fat intake was assessed using the Block Brief Food Frequency Questionnaire, which estimates average dietary intake based on 70 food items. The diets of individuals with no endoscopically identifiable lesions (n = 36) were compared to those with either ACF or polyps detected in the proximal colon. In multivariate analysis, high dietary intake of total polyunsaturated fatty acids (PUFAs) and intake of omega-6 and omega-3 fatty acids were positively associated with neoplastic lesions in the proximal colon. When comparing ACF and polyp groups separately, a positive association was observed for both proximal polyps (OR 2.28; CI 1.16-7.09) and ACF (OR 2.86; CI 1.16-7.09) for total PUFA intake. Furthermore, the prevalence of proximal ACF was increased with higher intake of omega-6 (OR 3.54; CI 1.32-9.47) and omega-3 fatty acids (OR 2.29; CI 1.02-5.13), although there was no discernible difference in the omega-6/omega-3 ratio. These results suggest that dietary PUFAs may be positively associated with risk of early neoplasia in the proximal colon. This study provides further evidence that dietary PUFA composition may play an important role in altering the microenvironment within the human colon.

  18. [Medical computer-aided detection method based on deep learning].

    PubMed

    Tao, Pan; Fu, Zhongliang; Zhu, Kai; Wang, Lili

    2018-03-01

    This paper performs a comprehensive study on the computer-aided detection for the medical diagnosis with deep learning. Based on the region convolution neural network and the prior knowledge of target, this algorithm uses the region proposal network, the region of interest pooling strategy, introduces the multi-task loss function: classification loss, bounding box localization loss and object rotation loss, and optimizes it by end-to-end. For medical image it locates the target automatically, and provides the localization result for the next stage task of segmentation. For the detection of left ventricular in echocardiography, proposed additional landmarks such as mitral annulus, endocardial pad and apical position, were used to estimate the left ventricular posture effectively. In order to verify the robustness and effectiveness of the algorithm, the experimental data of ultrasonic and nuclear magnetic resonance images are selected. Experimental results show that the algorithm is fast, accurate and effective.

  19. Screening for colon cancer: A test for occult blood.

    PubMed

    Khakimov, N; Khasanova, G; Ershova, K; Gibadullina, L; Vetkina, T; Lobisheva, G; Chumakova, A

    2015-01-01

    The relevance of the problem of colorectal cancer (CRC) is evident because of extremely high morbidity and mortality rates, associated with this disease. CRC is mostly diagnosed only at very advanced stages. The reduction of mortality can be achieved by the popularization of screening-methods for early identification of CRC and adenomatous polyps of the colon, which are proved to be precancerous condition. Fecal occult blood test is a well-known method of screening for CRC. The advantages of this method when compared, for example, with colonoscopy are its simplicity and cost-effectiveness.Two techniques are usually used for detection of occult blood in the stool: Hemoccult (Guaiac) test and immunochemical test for hemoglobin. There is no consensus among researchers regarding the validity of these tests for the diagnosis of colorectal cancer. For example, J.S. Mandel (1996) notes 60% sensitivity of Guaiac-test for the detection of the early forms of colorectal cancer, while O.I. Kit (2014) suggets that it is not higher than 30%. There are also various opinions about specificity of these two tests. To review the literature on the validity of the fecal occult blood tests for the diagnosis of CRC. We looked for articles (electronic versions) available for free in the full-text versions, published from June 1, 1990 to December 31, 2014 in Russian or English. The following databases were used for search: E-LIBRARY; Cochrane; MEDLINE; EMBASE; Google search. Only original research papers were analyzed. Literature reviews or systematic reviews were not taken for analyses. 1) use of Guaiac and/or immunochemical fecal occult blood test as screening-tests for the detection of colorectal cancer and/or colon polyps (1 cm or more in diameter) in people older than 45 years; 2) comparing of results with the results of colonoscopy (colonoscopy is counted by majority of the authors as a "gold standard" for the diagnosis of CRC and adenomatous polyps). Initial keyword search returned 803 000 results, of which 449 sources were selected. After reading the abstracts, 29 articles that met inclusion criteria were kept. 10 other articles were excluded after that because they did not contain enough data for extraction or did not contain a control group. At the final step 19 articles were used for meta-analysis.Forest plot and Rock curve, which were developed with inclusion of the data from all studies, showed heterogeneity of the data. Additional analyzes were performed in subgroups with different diagnoses and various tests.The sensitivity of the Guaiac test for the diagnosis of colorectal cancer varied from 0.13 to 1.00, and specificity - from 0.69 to 0.99. The sensitivity of the immunochemical test for the diagnosis of CRC ranged from 0.42 to 0.94 with specificity ranging from 0.40 to 1.00.The sensitivity of the Guaiac test for the diagnosis of the colon polyps was between 0.05 and 0.69, and its specificity - from 0.67 to 0.98. The sensitivity of the immunochemical test for the diagnosis of polyps was from 0.24 to 0.75, and its specificity - from 0.40 to 0.97.Bivariate analysis of the validity of Guaiac test and immunochemical method for the diagnosis of colorectal cancer showed better results for the immunochemical test compared to Guaiac test. The tests showed very similar results when used for the diagnosis of polyposis. Bivariate analysis, comparing the validity of tests for the diagnosis of colorectal cancer versus polyposis demonstrated better results for CRC.Multivariate analysis of the validity of the Guaiac and immunochemical tests for the diagnosis of colorectal cancer and polyps also showed better results for detection of colorectal cancer compared with the polyps for both tests. At the same time the highest validity for the diagnosis of CRC was demonstrated for immunochemical analysis. 1. The sensitivity of the Guaiac test for occult blood in stool is lower than its specificity.2. Broad dispersion of the validity characteristics of the fecal occult blood tests was observed.3. The validity of tests for occult blood was higher when they were used for detection of colorectal cancer than of colon polyposis.4. The highest validity rate has been demonstrated for the immunochemical test when it was used for colon cancer screening.

  20. Endoscopic Features of Mucous Cap Polyps: A Way to Predict Serrated Polyps.

    PubMed

    Moy, Brian T; Forouhar, Faripour; Kuo, Chia-Ling; Devers, Thomas J

    2018-04-27

    The aims of the study were to identify whether a mucous-cap predicts the presence of serrated polyps, and to determine whether additional endoscopic findings predict the presence of a sessile serrated adenomas/polyp (SSA/P). We analyzed 147 mucous-capped polyps with corresponding histology, during 2011-2014. Eight endoscopic features (presence of borders, elevation, rim of debris, location in the colon, size ≥10 mm, varicose vessels, nodularity, and alteration in mucosal folds) of mucous-capped polyps were examined to see if they can predict SSA/Ps. A total of 86% (n=126) of mucous-capped polyps were from the right sided serrated pathway (right-sided hyperplastic [n=83], SSA/Ps [n=43], traditional serrated adenoma [n=1]), 10% (n=15) were left-sided hyperplastic polyps, and 3% (n=5) were from the adenoma-carcinoma sequence. The presence of a mucous cap combined with varicose vessels was the only significant predictor for SSA/Ps. The other seven characteristics were not found to be statistically significant for SSA/Ps, although location in the colon and the presence of nodularity trended towards significance. Our study suggests that mucous-capped polyps have high predictability for being a part of the serrated pathway. Gastroenterologists should be alert for a mucous-capped polyp with varicose veins, as these lesions have a higher risk of SSA/P.

  1. Quantitative determination of polyphosphate in sediments using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy and partial least squares regression.

    PubMed

    Khoshmanesh, Aazam; Cook, Perran L M; Wood, Bayden R

    2012-08-21

    Phosphorus (P) is a major cause of eutrophication and subsequent loss of water quality in freshwater ecosystems. A major part of the flux of P to eutrophic lake sediments is organically bound or of biogenic origin. Despite the broad relevance of polyphosphate (Poly-P) in bioremediation and P release processes in the environment, its quantification is not yet well developed for sediment samples. Current methods possess significant disadvantages because of the difficulties associated with using a single extractant to extract a specific P compound without altering others. A fast and reliable method to estimate the quantitative contribution of microorganisms to sediment P release processes is needed, especially when an excessive P accumulation in the form of polyphosphate (Poly-P) occurs. Development of novel approaches for application of emerging spectroscopic techniques to complex environmental matrices such as sediments significantly contributes to the speciation models of P mobilization, biogeochemical nutrient cycling and development of nutrient models. In this study, for the first time Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy in combination with partial least squares (PLS) was used to quantify Poly-P in sediments. To reduce the high absorption matrix components in sediments such as silica, a physical extraction method was developed to separate sediment biological materials from abiotic particles. The aim was to achieve optimal separation of the biological materials from sediment abiotic particles with minimum chemical change in the sample matrix prior to ATR-FTIR analysis. Using a calibration set of 60 samples for the PLS prediction models in the Poly-P concentration range of 0-1 mg g(-1) d.w. (dry weight of sediment) (R(2) = 0.984 and root mean square error of prediction RMSEP = 0.041 at Factor-1) Poly-P could be detected at less than 50 μg g(-l) d.w. Using this technique, there is no solvent extraction or chemical treatment required, sample preparation is minimal and simple, and the analysis time is greatly reduced. The results from this study demonstrated the potential of ATR FT-IR spectroscopy as an alternative method to study Poly-P in sediments.

  2. Computer-aided detection of renal calculi from noncontrast CT images using TV-flow and MSER features.

    PubMed

    Liu, Jianfei; Wang, Shijun; Turkbey, Evrim B; Linguraru, Marius George; Yao, Jianhua; Summers, Ronald M

    2015-01-01

    Renal calculi are common extracolonic incidental findings on computed tomographic colonography (CTC). This work aims to develop a fully automated computer-aided diagnosis system to accurately detect renal calculi on CTC images. The authors developed a total variation (TV) flow method to reduce image noise within the kidneys while maintaining the characteristic appearance of renal calculi. Maximally stable extremal region (MSER) features were then calculated to robustly identify calculi candidates. Finally, the authors computed texture and shape features that were imported to support vector machines for calculus classification. The method was validated on a dataset of 192 patients and compared to a baseline approach that detects calculi by thresholding. The authors also compared their method with the detection approaches using anisotropic diffusion and nonsmoothing. At a false positive rate of 8 per patient, the sensitivities of the new method and the baseline thresholding approach were 69% and 35% (p < 1e - 3) on all calculi from 1 to 433 mm(3) in the testing dataset. The sensitivities of the detection methods using anisotropic diffusion and nonsmoothing were 36% and 0%, respectively. The sensitivity of the new method increased to 90% if only larger and more clinically relevant calculi were considered. Experimental results demonstrated that TV-flow and MSER features are efficient means to robustly and accurately detect renal calculi on low-dose, high noise CTC images. Thus, the proposed method can potentially improve diagnosis.

  3. Computer-aided detection of renal calculi from noncontrast CT images using TV-flow and MSER features

    PubMed Central

    Liu, Jianfei; Wang, Shijun; Turkbey, Evrim B.; Linguraru, Marius George; Yao, Jianhua; Summers, Ronald M.

    2015-01-01

    Purpose: Renal calculi are common extracolonic incidental findings on computed tomographic colonography (CTC). This work aims to develop a fully automated computer-aided diagnosis system to accurately detect renal calculi on CTC images. Methods: The authors developed a total variation (TV) flow method to reduce image noise within the kidneys while maintaining the characteristic appearance of renal calculi. Maximally stable extremal region (MSER) features were then calculated to robustly identify calculi candidates. Finally, the authors computed texture and shape features that were imported to support vector machines for calculus classification. The method was validated on a dataset of 192 patients and compared to a baseline approach that detects calculi by thresholding. The authors also compared their method with the detection approaches using anisotropic diffusion and nonsmoothing. Results: At a false positive rate of 8 per patient, the sensitivities of the new method and the baseline thresholding approach were 69% and 35% (p < 1e − 3) on all calculi from 1 to 433 mm3 in the testing dataset. The sensitivities of the detection methods using anisotropic diffusion and nonsmoothing were 36% and 0%, respectively. The sensitivity of the new method increased to 90% if only larger and more clinically relevant calculi were considered. Conclusions: Experimental results demonstrated that TV-flow and MSER features are efficient means to robustly and accurately detect renal calculi on low-dose, high noise CTC images. Thus, the proposed method can potentially improve diagnosis. PMID:25563255

  4. Prosthetically guided maxillofacial surgery: evaluation of the accuracy of a surgical guide and custom-made bone plate in oncology patients after mandibular reconstruction.

    PubMed

    Mazzoni, Simona; Marchetti, Claudio; Sgarzani, Rossella; Cipriani, Riccardo; Scotti, Roberto; Ciocca, Leonardo

    2013-06-01

    The aim of the present study was to evaluate the accuracy of prosthetically guided maxillofacial surgery in reconstructing the mandible with a free vascularized flap using custom-made bone plates and a surgical guide to cut the mandible and fibula. The surgical protocol was applied in a study group of seven consecutive mandibular-reconstructed patients who were compared with a control group treated using the standard preplating technique on stereolithographic models (indirect computer-aided design/computer-aided manufacturing method). The precision of both surgical techniques (prosthetically guided maxillofacial surgery and indirect computer-aided design/computer-aided manufacturing procedure) was evaluated by comparing preoperative and postoperative computed tomographic data and assessment of specific landmarks. With regard to midline deviation, no significant difference was documented between the test and control groups. With regard to mandibular angle shift, only one left angle shift on the lateral plane showed a statistically significant difference between the groups. With regard to angular deviation of the body axis, the data showed a significant difference in the arch deviation. All patients in the control group registered greater than 8 degrees of deviation, determining a facial contracture of the external profile at the lower margin of the mandible. With regard to condylar position, the postoperative condylar position was better in the test group than in the control group, although no significant difference was detected. The new protocol for mandibular reconstruction using computer-aided design/computer-aided manufacturing prosthetically guided maxillofacial surgery to construct custom-made guides and plates may represent a viable method of reproducing the patient's anatomical contour, giving the surgeon better procedural control and reducing procedure time. Therapeutic, III.

  5. Anniversary Paper: History and status of CAD and quantitative image analysis: The role of Medical Physics and AAPM

    PubMed Central

    Giger, Maryellen L.; Chan, Heang-Ping; Boone, John

    2008-01-01

    The roles of physicists in medical imaging have expanded over the years, from the study of imaging systems (sources and detectors) and dose to the assessment of image quality and perception, the development of image processing techniques, and the development of image analysis methods to assist in detection and diagnosis. The latter is a natural extension of medical physicists’ goals in developing imaging techniques to help physicians acquire diagnostic information and improve clinical decisions. Studies indicate that radiologists do not detect all abnormalities on images that are visible on retrospective review, and they do not always correctly characterize abnormalities that are found. Since the 1950s, the potential use of computers had been considered for analysis of radiographic abnormalities. In the mid-1980s, however, medical physicists and radiologists began major research efforts for computer-aided detection or computer-aided diagnosis (CAD), that is, using the computer output as an aid to radiologists—as opposed to a completely automatic computer interpretation—focusing initially on methods for the detection of lesions on chest radiographs and mammograms. Since then, extensive investigations of computerized image analysis for detection or diagnosis of abnormalities in a variety of 2D and 3D medical images have been conducted. The growth of CAD over the past 20 years has been tremendous—from the early days of time-consuming film digitization and CPU-intensive computations on a limited number of cases to its current status in which developed CAD approaches are evaluated rigorously on large clinically relevant databases. CAD research by medical physicists includes many aspects—collecting relevant normal and pathological cases; developing computer algorithms appropriate for the medical interpretation task including those for segmentation, feature extraction, and classifier design; developing methodology for assessing CAD performance; validating the algorithms using appropriate cases to measure performance and robustness; conducting observer studies with which to evaluate radiologists in the diagnostic task without and with the use of the computer aid; and ultimately assessing performance with a clinical trial. Medical physicists also have an important role in quantitative imaging, by validating the quantitative integrity of scanners and developing imaging techniques, and image analysis tools that extract quantitative data in a more accurate and automated fashion. As imaging systems become more complex and the need for better quantitative information from images grows, the future includes the combined research efforts from physicists working in CAD with those working on quantitative imaging systems to readily yield information on morphology, function, molecular structure, and more—from animal imaging research to clinical patient care. A historical review of CAD and a discussion of challenges for the future are presented here, along with the extension to quantitative image analysis. PMID:19175137

  6. Anniversary Paper: History and status of CAD and quantitative image analysis: The role of Medical Physics and AAPM

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Giger, Maryellen L.; Chan, Heang-Ping; Boone, John

    2008-12-15

    The roles of physicists in medical imaging have expanded over the years, from the study of imaging systems (sources and detectors) and dose to the assessment of image quality and perception, the development of image processing techniques, and the development of image analysis methods to assist in detection and diagnosis. The latter is a natural extension of medical physicists' goals in developing imaging techniques to help physicians acquire diagnostic information and improve clinical decisions. Studies indicate that radiologists do not detect all abnormalities on images that are visible on retrospective review, and they do not always correctly characterize abnormalities thatmore » are found. Since the 1950s, the potential use of computers had been considered for analysis of radiographic abnormalities. In the mid-1980s, however, medical physicists and radiologists began major research efforts for computer-aided detection or computer-aided diagnosis (CAD), that is, using the computer output as an aid to radiologists--as opposed to a completely automatic computer interpretation--focusing initially on methods for the detection of lesions on chest radiographs and mammograms. Since then, extensive investigations of computerized image analysis for detection or diagnosis of abnormalities in a variety of 2D and 3D medical images have been conducted. The growth of CAD over the past 20 years has been tremendous--from the early days of time-consuming film digitization and CPU-intensive computations on a limited number of cases to its current status in which developed CAD approaches are evaluated rigorously on large clinically relevant databases. CAD research by medical physicists includes many aspects--collecting relevant normal and pathological cases; developing computer algorithms appropriate for the medical interpretation task including those for segmentation, feature extraction, and classifier design; developing methodology for assessing CAD performance; validating the algorithms using appropriate cases to measure performance and robustness; conducting observer studies with which to evaluate radiologists in the diagnostic task without and with the use of the computer aid; and ultimately assessing performance with a clinical trial. Medical physicists also have an important role in quantitative imaging, by validating the quantitative integrity of scanners and developing imaging techniques, and image analysis tools that extract quantitative data in a more accurate and automated fashion. As imaging systems become more complex and the need for better quantitative information from images grows, the future includes the combined research efforts from physicists working in CAD with those working on quantitative imaging systems to readily yield information on morphology, function, molecular structure, and more--from animal imaging research to clinical patient care. A historical review of CAD and a discussion of challenges for the future are presented here, along with the extension to quantitative image analysis.« less

  7. Three-Dimensional Computer-Aided Detection of Microcalcification Clusters in Digital Breast Tomosynthesis.

    PubMed

    Jeong, Ji-Wook; Chae, Seung-Hoon; Chae, Eun Young; Kim, Hak Hee; Choi, Young-Wook; Lee, Sooyeul

    2016-01-01

    We propose computer-aided detection (CADe) algorithm for microcalcification (MC) clusters in reconstructed digital breast tomosynthesis (DBT) images. The algorithm consists of prescreening, MC detection, clustering, and false-positive (FP) reduction steps. The DBT images containing the MC-like objects were enhanced by a multiscale Hessian-based three-dimensional (3D) objectness response function and a connected-component segmentation method was applied to extract the cluster seed objects as potential clustering centers of MCs. Secondly, a signal-to-noise ratio (SNR) enhanced image was also generated to detect the individual MC candidates and prescreen the MC-like objects. Each cluster seed candidate was prescreened by counting neighboring individual MC candidates nearby the cluster seed object according to several microcalcification clustering criteria. As a second step, we introduced bounding boxes for the accepted seed candidate, clustered all the overlapping cubes, and examined. After the FP reduction step, the average number of FPs per case was estimated to be 2.47 per DBT volume with a sensitivity of 83.3%.

  8. Robust Nucleus/Cell Detection and Segmentation in Digital Pathology and Microscopy Images: A Comprehensive Review

    PubMed Central

    Xing, Fuyong; Yang, Lin

    2016-01-01

    Digital pathology and microscopy image analysis is widely used for comprehensive studies of cell morphology or tissue structure. Manual assessment is labor intensive and prone to inter-observer variations. Computer-aided methods, which can significantly improve the objectivity and reproducibility, have attracted a great deal of interest in recent literatures. Among the pipeline of building a computer-aided diagnosis system, nucleus or cell detection and segmentation play a very important role to describe the molecular morphological information. In the past few decades, many efforts have been devoted to automated nucleus/cell detection and segmentation. In this review, we provide a comprehensive summary of the recent state-of-the-art nucleus/cell segmentation approaches on different types of microscopy images including bright-field, phase-contrast, differential interference contrast (DIC), fluorescence, and electron microscopies. In addition, we discuss the challenges for the current methods and the potential future work of nucleus/cell detection and segmentation. PMID:26742143

  9. Evaluation of computer-aided detection of lesions in mammograms obtained with a digital phase-contrast mammography system.

    PubMed

    Tanaka, Toyohiko; Nitta, Norihisa; Ohta, Shinichi; Kobayashi, Tsuyoshi; Kano, Akiko; Tsuchiya, Keiko; Murakami, Yoko; Kitahara, Sawako; Wakamiya, Makoto; Furukawa, Akira; Takahashi, Masashi; Murata, Kiyoshi

    2009-12-01

    A computer-aided detection (CAD) system was evaluated for its ability to detect microcalcifications and masses on images obtained with a digital phase-contrast mammography (PCM) system, a system characterised by the sharp images provided by phase contrast and by the high resolution of 25-μm-pixel mammograms. Fifty abnormal and 50 normal mammograms were collected from about 3,500 mammograms and printed on film for reading on a light box. Seven qualified radiologists participated in an observer study based on receiver operating characteristic (ROC) analysis. The average of the areas under ROC curve (AUC) values for the ROC analysis with and without CAD were 0.927 and 0.897 respectively (P = 0.015). The AUC values improved from 0.840 to 0.888 for microcalcifications (P = 0.034) and from 0.947 to 0.962 for masses (P = 0.025) respectively. The application of CAD to the PCM system is a promising approach for the detection of breast cancer in its early stages.

  10. A new composite measure of colonoscopy: the Performance Indicator of Colonic Intubation (PICI).

    PubMed

    Valori, Roland M; Damery, Sarah; Gavin, Daniel R; Anderson, John T; Donnelly, Mark T; Williams, J Graham; Swarbrick, Edwin T

    2018-01-01

     Cecal intubation rate (CIR) is an established performance indicator of colonoscopy. In some patients, cecal intubation with acceptable tolerance is only achieved with additional sedation. This study proposes a composite Performance Indicator of Colonic Intubation (PICI), which combines CIR, comfort, and sedation. METHODS : Data from 20 085 colonoscopies reported in the 2011 UK national audit were analyzed. PICI was defined as the percentage of procedures achieving cecal intubation with median dose (2 mg) of midazolam or less, and nurse-assessed comfort score of 1 - 3/5. Multivariate logistic regression analysis evaluated possible associations between PICI and patient, unit, colonoscopist, and diagnostic factors. RESULTS : PICI was achieved in 54.1 % of procedures. PICI identified factors affecting performance more frequently than single measures such as CIR and polyp detection, or CIR + comfort alone. Older age, male sex, adequate bowel preparation, and a positive fecal occult blood test as indication were associated with a higher PICI. Unit accreditation, the presence of magnetic imagers in the unit, greater annual volume, fewer years' experience, and higher training/trainer status were associated with higher PICI rates. Procedures in which PICI was achieved were associated with significantly higher polyp detection rates than when PICI was not achieved. CONCLUSIONS : PICI provides a simpler picture of performance of colonoscopic intubation than separate measures of CIR, comfort, and sedation. It is associated with more factors that are amenable to change that might improve performance and with higher likelihood of polyp detection. It is proposed that PICI becomes the key performance indicator for intubation of the colon in colonoscopy quality improvement initiatives. © Georg Thieme Verlag KG Stuttgart · New York.

  11. Oral polyp as the presenting feature of Beckwith-Wiedemann syndrome in a child

    PubMed Central

    Kujan, Omar; Raheel, Syed Ahmed; King, David; Iqbal, Fareed

    2015-01-01

    Beckwith-Wiedemann syndrome (BWS) is a congenital growth disorder characterised by abdominal wall defects, macroglossia and somatic gigantism. A number of associated features, including gastrointestinal and urinary tract polyps, have been described, but there are no previous reports of oral polyps occurring in this syndrome. We describe the first case of BWS presenting with an oral polyp. Clinicians should be alert to the possibility of BWS if other features of the syndrome are present, in children with oral polyps. PMID:26323977

  12. Computer-aided detection of basal cell carcinoma through blood content analysis in dermoscopy images

    NASA Astrophysics Data System (ADS)

    Kharazmi, Pegah; Kalia, Sunil; Lui, Harvey; Wang, Z. Jane; Lee, Tim K.

    2018-02-01

    Basal cell carcinoma (BCC) is the most common type of skin cancer, which is highly damaging to the skin at its advanced stages and causes huge costs on the healthcare system. However, most types of BCC are easily curable if detected at early stage. Due to limited access to dermatologists and expert physicians, non-invasive computer-aided diagnosis is a viable option for skin cancer screening. A clinical biomarker of cancerous tumors is increased vascularization and excess blood flow. In this paper, we present a computer-aided technique to differentiate cancerous skin tumors from benign lesions based on vascular characteristics of the lesions. Dermoscopy image of the lesion is first decomposed using independent component analysis of the RGB channels to derive melanin and hemoglobin maps. A novel set of clinically inspired features and ratiometric measurements are then extracted from each map to characterize the vascular properties and blood content of the lesion. The feature set is then fed into a random forest classifier. Over a dataset of 664 skin lesions, the proposed method achieved an area under ROC curve of 0.832 in a 10-fold cross validation for differentiating basal cell carcinomas from benign lesions.

  13. At what costs will screening with CT colonography be competitive? A cost-effectiveness approach.

    PubMed

    Lansdorp-Vogelaar, Iris; van Ballegooijen, Marjolein; Zauber, Ann G; Boer, Rob; Wilschut, Janneke; Habbema, J Dik F

    2009-03-01

    The costs of computed tomographic colonography (CTC) are not yet established for screening use. In our study, we estimated the threshold costs for which CTC screening would be a cost-effective alternative to colonoscopy for colorectal cancer (CRC) screening in the general population. We used the MISCAN-colon microsimulation model to estimate the costs and life-years gained of screening persons aged 50-80 years for 4 screening strategies: (i) optical colonoscopy; and CTC with referral to optical colonoscopy of (ii) any suspected polyp; (iii) a suspected polyp >or=6 mm and (iv) a suspected polyp >or=10 mm. For each of the 4 strategies, screen intervals of 5, 10, 15 and 20 years were considered. Subsequently, for each CTC strategy and interval, the threshold costs of CTC were calculated. We performed a sensitivity analysis to assess the effect of uncertain model parameters on the threshold costs. With equal costs ($662), optical colonoscopy dominated CTC screening. For CTC to gain similar life-years as colonoscopy screening every 10 years, it should be offered every 5 years with referral of polyps >or=6 mm. For this strategy to be as cost-effective as colonoscopy screening, the costs must not exceed $285 or 43% of colonoscopy costs (range in sensitivity analysis: 39-47%). With 25% higher adherence than colonoscopy, CTC threshold costs could be 71% of colonoscopy costs. Our estimate of 43% is considerably lower than previous estimates in literature, because previous studies only compared CTC screening to 10-yearly colonoscopy, where we compared to different intervals of colonoscopy screening.

  14. Physician-patient and patient-family communication after colonoscopy.

    PubMed

    Jiménez, Jessica A; Jung, Barbara; Madlensky, Lisa

    2012-09-01

    A personal or family history of colorectal adenomas increases the risk of colorectal cancer (CRC). We aimed to compare physicians' communication with polyp patients vs. non-polyp patients, assess whether polyps or CRC family history were associated with physician-patient communication, and describe patients' disclosure of colonoscopy and polyp diagnosis to their relatives. Four hundred nine patients completed an online survey regarding physician-patient communication of colonoscopy results, perceived personal and familial risk of polyps and CRC, and disclosure of colonoscopy results to relatives. Six percent of participants reported that their physicians discussed familial risks. Polyp diagnosis and family history predicted physician-patient discussions about familial CRC risks. Polyp diagnosis predicted physician-patient discussions of future surveillance. Twenty-two percent of patients told none of their relatives that they had a colonoscopy. Family history, gender, and education were associated with patient-family communication. There is room for improvement in physician-patient and patient-family communication following colonoscopy.

  15. Chemoprevention of polyp recurrence with curcumin followed by silibinin in a case of multiple colorectal adenomas.

    PubMed

    Alfonso-Moreno, Vicente; López-Serrano, Antonio; Moreno-Osset, Eduardo

    2017-12-01

    Chemoprevention is a practical approach to reduce the risk of various cancers including colorectal cancer (CRC). The goal is to reduce the incidence of pre-neoplastic adenomatous polyps and prevent its progression to CRC. Curcumin and silibinin prevent intestinal polyp formation in mice. Curcumin sensitizes silymarin to exert synergistic anticancer activity in colon cancer cells. Patients presenting with multiple colorectal adenomatous polyps (MCRA) have a high lifetime risk for CRC. We present a 57-year-old man with MCRA, without deleterious germline APC or MYH mutations. Our patient had 54 polyps in the first colonoscopy, most of 3 to 8 mm and one of 20 mm with high grade dysplasia / adenocarcinoma. Four subsequent colonoscopies showed continuous development of adenomatous polyps treated by polypectomy for the most part and some with heat. After the treatment with curcumin for 3 months and a half followed by silibinin for 9 months, we find many less polyps than in the previous colonoscopies, going from the finding of 40 adenomas of 3-6 mm in the pre-treatment colonoscopy to 3 polyps after treatment.

  16. A Lactobacillus mutant capable of accumulating long-chain polyphosphates that enhance intestinal barrier function.

    PubMed

    Saiki, Asako; Ishida, Yasuaki; Segawa, Shuichi; Hirota, Ryuichi; Nakamura, Takeshi; Kuroda, Akio

    2016-05-01

    Inorganic polyphosphate (polyP) was previously identified as a probiotic-derived substance that enhances intestinal barrier function. PolyP-accumulating bacteria are expected to have beneficial effects on the human gastrointestinal tract. In this study, we selected Lactobacillus paracasei JCM 1163 as a strain with the potential to accumulate polyP, because among the probiotic bacteria stored in our laboratory, it had the largest amount of polyP. The chain length of polyP accumulated in L. paracasei JCM 1163 was approximately 700 phosphate (Pi) residues. L. paracasei JCM 1163 accumulated polyP when Pi was added to Pi-starved cells. We further improved the ability of L. paracasei JCM 1163 to accumulate polyP by nitrosoguanidine mutagenesis. The mutant accumulated polyP at a level of 1500 nmol/mg protein-approximately 190 times that of the wild-type strain. PolyP extracted from the L. paracasei JCM 1163 significantly suppressed the oxidant-induced intestinal permeability in mouse small intestine. In conclusion, we have succeeded in breeding the polyP-accumulating Lactobacillus mutant that is expected to enhance intestinal barrier function.

  17. Modulation of mitochondrial ion transport by inorganic polyphosphate - essential role in mitochondrial permeability transition pore.

    PubMed

    Baev, Artyom Y; Negoda, Alexander; Abramov, Andrey Y

    2017-02-01

    Inorganic polyphosphate (polyP) is a biopolymer of phosphoanhydride-linked orthophosphate residues. PolyP is involved in multiple cellular processes including mitochondrial metabolism and cell death. We used artificial membranes and isolated mitochondria to investigate the role of the polyP in mitochondrial ion transport and in activation of PTP. Here, we found that polyP can modify ion permeability of de-energised mitochondrial membranes but not artificial membranes. This permeability was selective for Ba 2+ and Ca 2+ but not for other monovalent and bivalent cations and can be blocked by inhibitors of the permeability transition pore - cyclosporine A or ADP. Lower concentrations of polyP modulate calcium dependent permeability transition pore opening. Increase in polyP concentrations and elongation chain length of the polymer causes calcium independent swelling in energized conditions. Physiologically relevant concentrations of inorganic polyP can regulate calcium dependent as well calcium independent mitochondrial permeability transition pore opening. This raises the possibility that cytoplasmic polyP can be an important contributor towards regulation of the cell death.

  18. Multiple polyps and colorectal cancer.

    PubMed

    Alecu, M; Simion, L; Straja, Nd; Brătucu, E

    2014-01-01

    Malignant degeneration as a possible course of evolution of colorectal polyps renders their diagnosis and therapeutic management a prophylactic act in the prevention of colorectal cancer (CRC). The study was conducted over a period of 3 years (2008-2011), during which 1,368 colonoscopies were performed in our service. The aim of the study was to identify patients presenting multiple colorectal polyps and to determine their risk factors for developing CRC, as well as to establish the appropriate therapeutic conduct. Presence of multiple polyps was recorded in over 40% of the patients identified with colorectal polyps of any kind. Dysplastic modifications observed during the histopathology exam presented a high incidence in the case of patients with multiple polyps, ranging from low-grade dysplasia to incipient CRC. Dysplastic modifications and carcinomatous foci were identified mostly among patients with multiple polyps.Only benign lesions or in situ carcinomas benefited from endoscopic treatment, poorly differentiated carcinomas or those invading the submucosa being treated by conventional surgery. Patients diagnosed with colorectal polyps require a rigorous post-therapy follow-up protocol, able to identify any eventual polyposis recurrence. Celsius.

  19. Correlation between transvaginal ultrasound measured endometrial thickness and histopathological findings in Turkish women with abnormal uterine bleeding.

    PubMed

    Ozer, Alev; Ozer, Serdar; Kanat-Pektas, Mine

    2016-05-01

    The present study aims to determine how transvaginal ultrasonography and histopathological examination findings are correlated in a cohort of premenopausal and postmenopausal Turkish women with abnormal uterine bleeding. This is a retrospective review of 350 Turkish women who underwent transvaginal ultrasonography and suction curettage as a result of abnormal uterine bleeding. Sonographic appearance of the endometrium was normal in 244 patients (69.7%), while homogeneous thickening was detected in 47 patients (13.4%) and cystic thickening in 21 patients (6.0%). A sonographic diagnosis of endometrial polyp was made in 38 patients (10.9%). Histopathological analysis of endometrial samplings revealed proliferative endometrium (36%), secretory endometrium (24.6%), decidualization (10.9%), endometrial polyp (8.3%), endometritis (6.8%), endometrial hyperplasia (4.6%), irregular shedding (3.7%), atrophic endometrium (3.1%), endometrial cancer (1.1%) and placental retention (0.9%). The sonographic and histopathological findings correlated significantly (χ(2) = 122 768, P = 0.001; r = 0.215, P = 0.001). Approximately 51% of the women with homogeneous endometrial thickening had proliferative endometrium. Only 44.7% of the women with ultrasonographically visualized endometrial polyps had histopathologically diagnosed endometrial polyps. Nearly 57% of the women with cystic endometrial thickening had proliferative endometrium. If there is no facility for hysteroscopy or hysteroscopy-guided endometrial biopsy for women with abnormal uterine bleeding, transvaginal ultrasonography findings can be efficiently used to make a preliminary diagnosis and, thus, notify the pathologists. © 2016 Japan Society of Obstetrics and Gynecology.

  20. Observation of rat's colon polyps in real time by mini-endoscopy and raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Andriana, Bibin Bintang; Mahardika, Anggara; Taketani, Akihiro; Sato, Hidetoshi

    2018-02-01

    Colorectal adenoma (CA) is a disease caused by various factors (such as genetic factors or environmental exposures). The appearance of colon polyp (CP) within colorectal might indicate the hint of CA development. Ball-lens hollow fiber Raman probe (BHRP) may has a high capability for detection of CA in living experimental animal and have already tested to rat's CP in this study, which was designed to collaborate between BHRP with mini-endoscopy to observe the biochemical alteration within normal colon tissue and rat's colon polyps in real time. BHRP and mini-endoscopy can distinguish the differences in their finger print spectra and make pictures the control and CP in the real time. At the first step, the real situation of normal colon and Rat's CP were washed by saline and observed with mini-endoscopy. BHRP was introduced to Dextran sodium sulphate (DSS)-induced Rat's CP to detect some of biochemical alteration. The main purpose of this study was to introduce mini-endoscopy to guide the BHRP for diagnosing of CP in real time and to compare it with spectra of normal colon (control group) in living rat. As the result, BHRP can provide the differences in band of control and CP group, which can inform that the biochemical of normal and CP has changed. As a major parameter to distinct normal and CP tissue were phosphatidylinositol, phosphodiester group, lipid, and collagen. Mini endoscopy and BHRP is very sensitive devices for diagnosing of CP in real time.

  1. Colonoscopic screening shows increased early incidence and progression of adenomas in cystic fibrosis

    PubMed Central

    Niccum, David E.; Billings, Joanne L.; Dunitz, Jordan M.; Khoruts, Alexander

    2018-01-01

    Background Colorectal cancer is an emerging problem in cystic fibrosis (CF). The goal of this study was to evaluate adenoma detection by systematic colonoscopic screening and surveillance. Methods We analyzed prospectively collected results of colonoscopies initiated at age 40 years from 88 CF patients at a single Cystic Fibrosis Center. We also reviewed results of diagnostic colonoscopies from 27 patients aged 30–39 years performed during the same time period at the Center. Results The incidence of polyp detection increased markedly after age 40 in CF patients. Greater than 50% were found to have adenomatous polyps; approximately 25% had advanced adenomas as defined by size and/or histopathology; 3% were found to have colon cancer. Multivariate analysis demonstrated specific risk factors for adenoma formation and progression. Conclusions Early screening and more frequent surveillance should be considered in patients with CF due to early incidence and progression of adenomas in this patient population. PMID:26851188

  2. Risk factor assessment of endoscopically removed malignant colorectal polyps.

    PubMed

    Netzer, P; Forster, C; Biral, R; Ruchti, C; Neuweiler, J; Stauffer, E; Schönegg, R; Maurer, C; Hüsler, J; Halter, F; Schmassmann, A

    1998-11-01

    Malignant colorectal polyps are defined as endoscopically removed polyps with cancerous tissue which has invaded the submucosa. Various histological criteria exist for managing these patients. To determine the significance of histological findings of patients with malignant polyps. Five pathologists reviewed the specimens of 85 patients initially diagnosed with malignant polyps. High risk malignant polyps were defined as having one of the following: incomplete polypectomy, a margin not clearly cancer-free, lymphatic or venous invasion, or grade III carcinoma. Adverse outcome was defined as residual cancer in a resection specimen and local or metastatic recurrence in the follow up period (mean 67 months). Malignant polyps were confirmed in 70 cases. In the 32 low risk malignant polyps, no adverse outcomes occurred; 16 (42%) of the 38 patients with high risk polyps had adverse outcomes (p<0.001). Independent adverse risk factors were incomplete polypectomy and a resected margin not clearly cancer-free; all other risk factors were only associated with adverse outcome when in combination. As no patients with low risk malignant polyps had adverse outcomes, polypectomy alone seems sufficient for these cases. In the high risk group, surgery is recommended when either of the two independent risk factors, incomplete polypectomy or a resection margin not clearly cancer-free, is present or if there is a combination of other risk factors. As lymphatic or venous invasion or grade III cancer did not have an adverse outcome when the sole risk factor, operations in such cases should be individually assessed on the basis of surgical risk.

  3. Association Between Visceral Adiposity and Colorectal Polyps on CT Colonography

    PubMed Central

    Summers, Ronald M.; Liu, Jiamin; Sussman, Daniel L.; Dwyer, Andrew J.; Rehani, Bhavya; Pickhardt, Perry J.; Choi, J. Richard; Yao, Jianhua

    2012-01-01

    OBJECTIVE To determine if there is an association between visceral adiposity measured on CT colonography (CTC) and colorectal polyps. MATERIALS AND METHODS The study was HIPAA-compliant and approved by our Institutional Review Board and Office of Human Subjects Research. 1186 patients who underwent CTC and same day optical colonoscopy were analyzed. Visceral adipose tissue volumes (VAV) and volume percents relative to total internal body volume (VAV%) were measured on slices in the L2–L3 regions on supine CTC scan with validated fully-automated software. Student t-test, odds ratio (OR), logistic regression and receiver operating characteristic analyses were performed. RESULTS For subjects with and without adenomatous polyps, means and s. d. of VAV% were 31.2 ± 10.8% (n=345) and 28.2% ± 11.3% (n=841) (p<0.0001), respectively. For subjects with and without hyperplastic polyps they were 31.8% ± 10.7% (n=244) and 28.3% ± 11.2% (n=942) (p<0.0001), respectively. Comparing the lowest and highest quintiles of VAV%, the ORs for having at least one adenomatous polyp or hyperplastic polyp versus no polyp were 2.06 (95% CI: 1.36–3.13) and 1.71 [1.08, 2.71] and the prevalence of having adenomatous polyps or hyperplastic polyps increased 14% and 8%, respectively. CONCLUSION Subjects with higher visceral adiposity measurements on CTC have a greater risk for the presence of colonic polyps. PMID:22733893

  4. Polyphosphate kinase: demonstration that short chain polyphosphate serves as a primer for the enzymatic synthesis of polyphosphate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Robinson, N.A.; Wood, H.G.

    1986-05-01

    Polyphosphate (poly(P)) kinase, isolated from Propionibacterium shermanii, catalyzes the following reaction: poly(P/sub n/) + ATPin equilibriumpoly(P/sub n+1/) + ADP. The authors have purified this enzyme to 90% homogeneity and have shown it to be composed of 2-3 identical subunits of M/sub r/ 80,000. Investigation of the reaction mechanism by product analysis has revealed that the elongation phase is processive whereby successive elongation occurs without release of intermediate sizes until very long chains are formed. The initiation phase of synthesis has been investigated using (/sup 32/P) poly(P) primer of chain length 11-60. It is incorporated into long chain poly(P) and themore » /sup 32/P has been shown, by use of poly(P) glucokinase, to be localized at the end of the molecule. Calculation of average chain length based upon the incorporation of /sup 32/P, however, yields a value approx.3 fold higher than the value calculated by another method using poly(P) glucokinase. This result indicates that initiation of poly(P) synthesis occurs by at least one other route which does not involve short chain poly(P) primers. The effect of temperature and concentration of poly(P) primer upon the average chain length of poly(P) synthesized was also investigated. A general trend was observed in which the chain length of the synthesized poly(P) decreased as either temperature or concentration or primer was increased.« less

  5. Recurrent Obstructive Giant Inflammatory Polyposis of the Colon

    PubMed Central

    Budhraja, Vikram

    2016-01-01

    Inflammatory polyps are relatively common in patients with inflammatory bowel disease. The term giant inflammatory polyposis is used to describe inflammatory polyps greater than 1.5 cm in any dimension. Their clinical presentation can be varied, ranging from asymptomatic, with incidental detection on radiological or endoscopic testing, to symptomatic, with rectal bleeding and colonic obstruction. Although giant inflammatory polyposis is a rare finding, it is of clinical importance, since it is easily mistaken for colon cancer, with patients sometimes undergoing radical surgeries. We describe an unusual case of giant inflammatory polyposis causing recurrent symptomatic obstruction despite multiple segmental colectomies in a patient with indeterminate colitis. This is the first such reported case in English literature to the best of our knowledge. PMID:27807551

  6. Recurrent Obstructive Giant Inflammatory Polyposis of the Colon.

    PubMed

    Syal, Gaurav; Budhraja, Vikram

    2016-08-01

    Inflammatory polyps are relatively common in patients with inflammatory bowel disease. The term giant inflammatory polyposis is used to describe inflammatory polyps greater than 1.5 cm in any dimension. Their clinical presentation can be varied, ranging from asymptomatic, with incidental detection on radiological or endoscopic testing, to symptomatic, with rectal bleeding and colonic obstruction. Although giant inflammatory polyposis is a rare finding, it is of clinical importance, since it is easily mistaken for colon cancer, with patients sometimes undergoing radical surgeries. We describe an unusual case of giant inflammatory polyposis causing recurrent symptomatic obstruction despite multiple segmental colectomies in a patient with indeterminate colitis. This is the first such reported case in English literature to the best of our knowledge.

  7. Risk factor assessment of endoscopically removed malignant colorectal polyps

    PubMed Central

    Netzer, P; Forster, C; Biral, R; Ruchti, C; Neuweiler, J; Stauffer, E; Schonegg, R; Maurer, C; Husler, J; Halter, F; Schmassmann, A

    1998-01-01

    Background—Malignant colorectal polyps are defined as endoscopically removed polyps with cancerous tissue which has invaded the submucosa. Various histological criteria exist for managing these patients. 
Aims—To determine the significance of histological findings of patients with malignant polyps. 
Methods—Five pathologists reviewed the specimens of 85 patients initially diagnosed with malignant polyps. High risk malignant polyps were defined as having one of the following: incomplete polypectomy, a margin not clearly cancer-free, lymphatic or venous invasion, or grade III carcinoma. Adverse outcome was defined as residual cancer in a resection specimen and local or metastatic recurrence in the follow up period (mean 67months). 
Results—Malignant polyps were confirmed in 70 cases. In the 32 low risk malignant polyps, no adverse outcomes occurred; 16(42%) of the 38 patients with high risk polyps had adverse outcomes (p<0.001). Independent adverse risk factors were incomplete polypectomy and a resected margin not clearly cancer-free; all other risk factors were only associated with adverse outcome when in combination. 
Conclusion—As no patients with low risk malignant polyps had adverse outcomes, polypectomy alone seems sufficient for these cases. In the high risk group, surgery is recommended when either of the two independent risk factors, incomplete polypectomy or a resection margin not clearly cancer-free, is present or if there is a combination of other risk factors. As lymphatic or venous invasion or grade III cancer did not have an adverse outcome when the sole risk factor, operations in such cases should be individually assessed on the basis of surgical risk. 

 Keywords: malignant polyps; colon cancer; colonoscopy; polypectomy; histology PMID:9824349

  8. Prevalence of endometrial polyps coexisting with uterine fibroids and associated factors

    PubMed Central

    Kınay, Tuğba; Öztürk Başarır, Zehra; Fırtına Tuncer, Serap; Akpınar, Funda; Kayıkçıoğlu, Fulya; Koç, Sevgi

    2016-01-01

    Objective: The aim of the study was to investigate the prevalence of endometrial polyps in patients with uterine fibroids and associated factors of coexistence of these two pathologies. Materials and Methods: The medical records of 772 patients who underwent hysterectomy because of uterine fibroids were retrospectively reviewed. Patients were divided into two groups according to the presence of endometrial polyps in the histopathologic examination. Demographic, clinical and histopathologic findings of the patients with and without endometrial polyps were compared. Student’s t-test, Mann-Whitney U test, Pearson’s Chi-square test, and logistic regression analysis were used for statistical analysis. Results: The prevalence of the endometrial polyps in uterine fibroid cases was found 20.1% (n=155). Age ≥45 years (odds ratio [OR] 1.61; 95% confidence interval [CI]: [1.06-2.44]; p=0.014), presence of hypertension (23.9% vs. 17.5%; p=0.047), endometrial hyperplasia (OR 4.00; 95% CI: [1.92-8.33]; p<0.001) and cervical polyps (OR 3.13; 95% CI: [1.69-5.88]; p<0.001) were significantly associated with the coexistence of endometrial polyps and uterine fibroids. Endometrial polyps were more common in patients with ≥2 fibroids (p=0.023) and largest fibroid <8 cm (p=0.009). A negative correlation was found between condom use and endometrial polyps (8.1% vs. 3.9%; p=0.044). Conclusions: The prevalence of the endometrial polyps coexisting with uterine fibroids was 20.1%. Age, hypertension, endometrial hyperplasia, cervical polyps, and number of fibroids were positively correlated; condom use and size of largest fibroid were negatively correlated with the coexistence of these two pathologies. PMID:28913086

  9. Evaluation of patients with gastric polyps.

    PubMed

    Olmez, Sehmus; Sayar, Suleyman; Saritas, Bunyamin; Savas, Ayla Yildiz; Avcioglu, Ufuk; Tenlik, Ilyas; Ozaslan, Ersan; Koseoglu, Hasan Tankut; Altiparmak, Emin

    2018-01-01

    The incidence of gastric polyps (GPs) greatly differs according to study populations and was found to be 0.33%-6.7% in various studies. The majority of GPs are composed of hyperplastic polyps (HPs), fundic gland polyps (FGPs), and adenomatous polyps (APs). Although APs have a high risk of malignant potential, sporadic FGPs have no malignant potential. Conversely, HPs have a low risk of malignant potential. It is not sufficient to perform a biopsy to identify the polyp type and the presence of dysplasia; thus, some polyps may require multiple biopsies or total excision. This retrospective study included patients with GPs or polypoid lesions found on esophagogastroscopy with polyp or malignant histology on biopsy at Ankara Numune Training and Research Hospital Endoscopy Unit between 2005 and 2011. In a series of 56.300 upper endoscopies, 192 patients (0.34%) were found to have GPs. Among the patients, 51 (26.6%) were men and 151 (73.4%) were women. The average age of the patients was 61.9±13.3 (14-90) years. The frequency of HPs, APs, and FGPs were 88%, 2.6%, and 1.6%, respectively. The size of the polyps was ≤1 cm in 137 (70%) patients. One polyp was determined in 141 (73.4%) patients. The most common localizations of polyps were the antrum and corpus. Endoscopic snare polypectomy was performed in 64 patients. One bleeding episode was observed, which required endoscopic treatment after ESP. In our study, the GP frequency was low (0.34%), whereas the frequency of HP maybe high due to the high frequency of Helicobacter pylori (HPy) infection in our country. The frequency of FGP is probably low due to the high frequency of HPy infection and the short-term use of proton-pump inhibitors.

  10. Diagnostic accuracy of transabdominal high-resolution US for staging gallbladder cancer and differential diagnosis of neoplastic polyps compared with EUS.

    PubMed

    Lee, Jeong Sub; Kim, Jung Hoon; Kim, Yong Jae; Ryu, Ji Kon; Kim, Yong-Tae; Lee, Jae Young; Han, Joon Koo

    2017-07-01

    To compare the diagnostic accuracy of transabdominal high-resolution ultrasound (HRUS) for staging gallbladder cancer and differential diagnosis of neoplastic polyps compared with endoscopic ultrasound (EUS) and pathology. Among 125 patients who underwent both HRUS and EUS, we included 29 pathologically proven cancers (T1 = 7, T2 = 19, T3 = 3) including 15 polypoid cancers and 50 surgically proven polyps (neoplastic = 30, non-neoplastic = 20). We reviewed formal reports and assessed the accuracy of HRUS and EUS for diagnosing cancer as well as the differential diagnosis of neoplastic polyps. Statistical analyses were performed using chi-square tests. The sensitivity, specificity, PPV, and NPV for gallbladder cancer were 82.7 %, 44.4 %, 82.7 %, and 44 % using HRUS and 86.2 %, 22.2 %, 78.1 %, and 33.3 % using EUS. HRUS and EUS correctly diagnosed the stage in 13 and 12 patients. The sensitivity, specificity, PPV, and NPV for neoplastic polyps were 80 %, 80 %, 86 %, and 73 % using HRUS and 73 %, 85 %, 88 %, and 69 % using EUS. Single polyps (8/20 vs. 21/30), larger (1.0 ± 0.28 cm vs. 1.9 ± 0.85 cm) polyps, and older age (52.5 ± 13.2 vs. 66.1 ± 10.3 years) were common in neoplastic polyps (p < 0.05). Transabdominal HRUS showed comparable accuracy for diagnosing gallbladder cancer and differentiating neoplastic polyps compared with EUS. HRUS is also easy to use during our routine ultrasound examinations. • HRUS showed comparable diagnostic accuracy for GB cancer compared with EUS. • HRUS and EUS showed similar diagnostic accuracy for differentiating neoplastic polyps. • Single, larger polyps and older age were common in neoplastic polyps. • HRUS is less invasive compared with EUS.

  11. High-resolution sonography for distinguishing neoplastic gallbladder polyps and staging gallbladder cancer.

    PubMed

    Kim, Jung Hoon; Lee, Jae Young; Baek, Jee Hyun; Eun, Hyo Won; Kim, Young Jae; Han, Joon Koo; Choi, Byung Ihn

    2015-02-01

    OBJECTIVE. The purposes of this study were to compare staging accuracy of high-resolution sonography (HRUS) with combined low- and high-MHz transducers with that of conventional sonography for gallbladder cancer and to investigate the differences in the imaging findings of neoplastic and nonneoplastic gallbladder polyps. MATERIALS AND METHODS. Our study included 37 surgically proven gallbladder cancer (T1a = 7, T1b = 2, T2 = 22, T3 = 6), including 15 malignant neoplastic polyps and 73 surgically proven polyps (neoplastic = 31, nonneoplastic = 42) that underwent HRUS and conventional transabdominal sonography. Two radiologists assessed T-category and predefined polyp findings on HRUS and conventional transabdominal sonography. Statistical analyses were performed using chi-square and McNemar tests. RESULTS. The diagnostic accuracy for the T category was T1a = 92-95%, T1b = 89-95%, T2 = 78-86%, and T3 = 84-89%, all with good agreement (κ = 0.642) using HRUS. The diagnostic accuracy for differentiating T1 from T2 or greater than T2 was 92% and 89% on HRUS and 65% and 70% with conventional transabdominal sonography. Statistically common findings for neoplastic polyps included size greater than 1 cm, single lobular surface, vascular core, hypoechoic polyp, and hypoechoic foci (p < 0.05). The value of HRUS in the differential diagnosis of a gallbladder polyp was more clearly depicted internal echo foci than conventional transabdominal sonography (39 vs 21). A polyp size greater than 1 cm was independently associated with a neoplastic polyp (odds ratio = 7.5, p = 0.02). The AUC of a polyp size greater than 1 cm was 0.877. The sensitivity and specificity were 66.67% and 89.13%, respectively. CONCLUSION. HRUS is a simple method that enables accurate T categorization of gallbladder carcinoma. It provides high-resolution images of gallbladder polyps and may have a role in stratifying the risk for malignancy.

  12. A prospective comparison of cold snare polypectomy using traditional or dedicated cold snares for the resection of small sessile colorectal polyps

    PubMed Central

    Dwyer, Jeremy P.; Tan, Jonathan Y. C.; Urquhart, Paul; Secomb, Robyn; Bunn, Catherine; Reynolds, John; La Nauze, Richard; Kemp, William; Roberts, Stuart; Brown, Gregor

    2017-01-01

    Background and study aims  The evidence for efficacy and safety of cold snare polypectomy is limited. The aim of this study was to assess the completeness of resection and safety of cold snare polypectomy, using either traditional or dedicated cold snares. Patients and methods  This was a prospective, non-randomized study performed at a single tertiary hospital. Adult patients with at least one colorectal polyp (size ≤ 10 mm) removed by cold snare were included. In the first phase, all patients had polyps removed by traditional snare without diathermy. In the second phase, all patients had polyps removed by dedicated cold snare. Complete endoscopic resection was determined from histological examination of quadrantic polypectomy margin biopsies. Immediate or delayed bleeding within 2 weeks was recorded. Results  In total, 181 patients with 299 eligible polyps (n = 93 (173 polyps) traditional snare group, n = 88 (126 polyps) dedicated cold snare group) were included. Patient demographics and procedure indications were similar between groups. Mean polyp size was 6 mm in both groups ( P  = 0.25). Complete polyp resection was 165 /173 (95.4 %; 95 %CI 90.5 – 97.6 %) in the traditional snare group and 124/126 (98.4 %; 95 %CI 93.7 – 99.6 %) in the dedicated cold snare group ( P  = 0.16). Serrated polyps, compared with adenomatous polyps, had a higher rate of incomplete resection (7 % vs. 2 %, P  = 0.03). There was no statistically significant difference in the rate of immediate bleeding (3 % vs. 1 %, P  = 0.41) and there were no delayed hemorrhages or perforations. Conclusions  Cold snare polypectomy is effective and safe for the complete endoscopic resection of small (≤ 10 mm) colorectal polyps with either traditional or dedicated cold snares. PMID:29250580

  13. Terrestrial implications of mathematical modeling developed for space biomedical research

    NASA Technical Reports Server (NTRS)

    Lujan, Barbara F.; White, Ronald J.; Leonard, Joel I.; Srinivasan, R. Srini

    1988-01-01

    This paper summarizes several related research projects supported by NASA which seek to apply computer models to space medicine and physiology. These efforts span a wide range of activities, including mathematical models used for computer simulations of physiological control systems; power spectral analysis of physiological signals; pattern recognition models for detection of disease processes; and computer-aided diagnosis programs.

  14. Laparoscopic cholecystectomy in the treatment of gallbladder polypoid lesions--15 years of experience.

    PubMed

    Matłok, Maciej; Migaczewski, Marcin; Major, Piotr; Pędziwiatr, Michał; Budzyński, Piotr; Winiarski, Marek; Ostachowski, Mateusz; Budzyński, Andrzej; Rembiasz, Kazimierz

    2013-11-01

    Due to the constant increase of public health awareness and widespread "cancerophobia", the progressively larger number of incidentally diagnosed gall-bladder polyps became the source of anxiety, which leads patients and physicians to undertake therapeutic decisions, despite the absence of symptoms. The majority of gall-bladder polyps are benign. It is estimated that only 3 to 5% of polyps are malignant. Currently, there is lack of randomized control trials based on which the clear-cut criteria of qualification of patients with gall-bladder polyps for surgical procedure can be created. The aim of the study was to analyze gall-bladder polyps in patients who underwent laparoscopic cholecystectomy in the 2nd Department of General Surgery, Jagiellonian University Collegium Medicum. The retrospective study was conducted on 5369 patients who underwent laparoscopic cholecystectomy in the 2nd Department of General Surgery, Jagiellonian University Collegium Medicum with special attention to 152 (2.8%) patients in whom gall-bladder polyps were diagnosed preoperatively. Qualification criteria for surgery, surgical treatment results, and histopathological examination results were also analyzed. Amongst the 5369 patients qualified for laparoscopic cholecystectomy, 152 (2.8%) were diagnosed with gall-bladder polyps during the preoperative ultrasound examinations. Postoperative histopathological examinations of 41 (27%) patients confirmed the presence of gall-bladder polyps. In 102 (67%) patients, only gall-stones were diagnosed without previously described polyps during the ultrasound examination. Analysis of the histopathological examination results revealed the presence of benign lesions in 35 (23.35%) patients. In 5 (3%) patients the presence of an adenoma, and in one (0.65%) the presence of adenocarcinoma were confirmed. Based on the conducted study and previous personal experience in the treatment of patients with gall-bladder polyps, we believe that due to the potential risk of neoplastic transformation, patients with polyps larger than 10 mm in diameter and polyps of proven rapid growth should be qualified for laparoscopic cholecystectomy. Indications for surgical treatment also seem reasonable in case of patients with present polyps and coexisting right upper quadrant pain, even though the above-mentioned is connected with gall-bladder deposits.

  15. Endoscopic innovations to increase the adenoma detection rate during colonoscopy

    PubMed Central

    Dik, Vincent K; Moons, Leon MG; Siersema, Peter D

    2014-01-01

    Up to a quarter of polyps and adenomas are missed during colonoscopy due to poor visualization behind folds and the inner curves of flexures, and the presence of flat lesions that are difficult to detect. These numbers may however be conservative because they mainly come from back-to-back studies performed with standard colonoscopes, which are unable to visualize the entire mucosal surface. In the past several years, new endoscopic techniques have been introduced to improve the detection of polyps and adenomas. The introduction of high definition colonoscopes and visual image enhancement technologies have been suggested to lead to better recognition of flat and small lesions, but the absolute increase in diagnostic yield seems limited. Cap assisted colonoscopy and water-exchange colonoscopy are methods to facilitate cecal intubation and increase patients comfort, but show only a marginal or no benefit on polyp and adenoma detection. Retroflexion is routinely used in the rectum for the inspection of the dentate line, but withdrawal in retroflexion in the colon is in general not recommended due to the risk of perforation. In contrast, colonoscopy with the Third-Eye Retroscope® may result in considerable lower miss rates compared to standard colonoscopy, but this technique is not practical in case of polypectomy and is more time consuming. The recently introduced Full Spectrum Endoscopy™ colonoscopes maintains the technical capabilities of standard colonoscopes and provides a much wider view of 330 degrees compared to the 170 degrees with standard colonoscopes. Remarkable lower adenoma miss rates with this new technique were recently demonstrated in the first randomized study. Nonetheless, more studies are required to determine the exact additional diagnostic yield in clinical practice. Optimizing the efficacy of colorectal cancer screening and surveillance requires high definition colonoscopes with improved virtual chromoendoscopy technology that visualize the whole colon mucosa while maintaining optimal washing, suction and therapeutic capabilities, and keeping the procedural time as low and patient discomfort as optimal as possible. PMID:24605019

  16. F18 FDG positron emission tomography revelation of primary testicular lymphoma with concurrent multiple extra nodal involvement

    PubMed Central

    Vamsy, Mohana; Dattatreya, PS; Parakh, Megha; Dayal, Monal; Rao, VVS Prabhakar

    2013-01-01

    Primary testicular lymphoma (PTL) a relatively rare disease of non-Hodgkin's lymphomas occurring with a lesser incidence of 1-2% has a propensity to occur at later ages above 50 years. PTL spreads to extra nodal sites due to deficiency of extra cellular adhesion molecules. We present detection of multiple sites of extra nodal involvement of PTL by F-18 positron emission tomography/computed tomography study aiding early detection of the dissemination thus aiding in staging and management. PMID:24019676

  17. Inflammatory fibroid polyp of sigmoid colon.

    PubMed

    Lifschitz, O; Lew, S; Witz, M; Reiss, R; Griffel, B

    1979-01-01

    A case of inflammatory fibroid polyp of the sigmoid colon is presented. This is the eight case of this type of polyp in the colon and, to the best of our knowledge, the first one involving the sigmoid and producing intussusception. Symptomatology of the inflamed fibroid polyp in this part of the gut closely simulates gastrointestinal malignancy. The treatment is surgical excision of the polyp, or colonoscopic resection when it is possible. Intraoperative colonoscopy helps the surgeon to localize the lesion and to role out the existence of other lesions.

  18. Deep Convolutional Neural Networks for Computer-Aided Detection: CNN Architectures, Dataset Characteristics and Transfer Learning.

    PubMed

    Shin, Hoo-Chang; Roth, Holger R; Gao, Mingchen; Lu, Le; Xu, Ziyue; Nogues, Isabella; Yao, Jianhua; Mollura, Daniel; Summers, Ronald M

    2016-05-01

    Remarkable progress has been made in image recognition, primarily due to the availability of large-scale annotated datasets and deep convolutional neural networks (CNNs). CNNs enable learning data-driven, highly representative, hierarchical image features from sufficient training data. However, obtaining datasets as comprehensively annotated as ImageNet in the medical imaging domain remains a challenge. There are currently three major techniques that successfully employ CNNs to medical image classification: training the CNN from scratch, using off-the-shelf pre-trained CNN features, and conducting unsupervised CNN pre-training with supervised fine-tuning. Another effective method is transfer learning, i.e., fine-tuning CNN models pre-trained from natural image dataset to medical image tasks. In this paper, we exploit three important, but previously understudied factors of employing deep convolutional neural networks to computer-aided detection problems. We first explore and evaluate different CNN architectures. The studied models contain 5 thousand to 160 million parameters, and vary in numbers of layers. We then evaluate the influence of dataset scale and spatial image context on performance. Finally, we examine when and why transfer learning from pre-trained ImageNet (via fine-tuning) can be useful. We study two specific computer-aided detection (CADe) problems, namely thoraco-abdominal lymph node (LN) detection and interstitial lung disease (ILD) classification. We achieve the state-of-the-art performance on the mediastinal LN detection, and report the first five-fold cross-validation classification results on predicting axial CT slices with ILD categories. Our extensive empirical evaluation, CNN model analysis and valuable insights can be extended to the design of high performance CAD systems for other medical imaging tasks.

  19. Evaluation of computer-aided diagnosis (CAD) software for the detection of lung nodules on multidetector row computed tomography (MDCT): JAFROC study for the improvement in radiologists' diagnostic accuracy.

    PubMed

    Hirose, Tomohiro; Nitta, Norihisa; Shiraishi, Junji; Nagatani, Yukihiro; Takahashi, Masashi; Murata, Kiyoshi

    2008-12-01

    The aim of this study was to evaluate the usefulness of computer-aided diagnosis (CAD) software for the detection of lung nodules on multidetector-row computed tomography (MDCT) in terms of improvement in radiologists' diagnostic accuracy in detecting lung nodules, using jackknife free-response receiver-operating characteristic (JAFROC) analysis. Twenty-one patients (6 without and 15 with lung nodules) were selected randomly from 120 consecutive thoracic computed tomographic examinations. The gold standard for the presence or absence of nodules in the observer study was determined by consensus of two radiologists. Six expert radiologists participated in a free-response receiver operating characteristic study for the detection of lung nodules on MDCT, in which cases were interpreted first without and then with the output of CAD software. Radiologists were asked to indicate the locations of lung nodule candidates on the monitor with their confidence ratings for the presence of lung nodules. The performance of the CAD software indicated that the sensitivity in detecting lung nodules was 71.4%, with 0.95 false-positive results per case. When radiologists used the CAD software, the average sensitivity improved from 39.5% to 81.0%, with an increase in the average number of false-positive results from 0.14 to 0.89 per case. The average figure-of-merit values for the six radiologists were 0.390 without and 0.845 with the output of the CAD software, and there was a statistically significant difference (P < .0001) using the JAFROC analysis. The CAD software for the detection of lung nodules on MDCT has the potential to assist radiologists by increasing their accuracy.

  20. Evaluation of a computer-aided detection algorithm for timely diagnosis of small acute intracranial hemorrhage on computed tomography in a critical care environment

    NASA Astrophysics Data System (ADS)

    Lee, Joon K.; Chan, Tao; Liu, Brent J.; Huang, H. K.

    2009-02-01

    Detection of acute intracranial hemorrhage (AIH) is a primary task in the interpretation of computed tomography (CT) brain scans of patients suffering from acute neurological disturbances or after head trauma. Interpretation can be difficult especially when the lesion is inconspicuous or the reader is inexperienced. We have previously developed a computeraided detection (CAD) algorithm to detect small AIH. One hundred and thirty five small AIH CT studies from the Los Angeles County (LAC) + USC Hospital were identified and matched by age and sex with one hundred and thirty five normal studies. These cases were then processed using our AIH CAD system to evaluate the efficacy and constraints of the algorithm.

  1. Developments in Colorectal Cancer Screening | NIH MedlinePlus the Magazine

    MedlinePlus

    ... cancer screening test for them? Colonoscopy is considered the gold standard. It is effective for screening and detection, and it is therapeutic as well since adenomas (a type of precancerous polyp) ... be removed. That’s the biggest advantage of colonoscopy as opposed to all ...

  2. In Vitro Effects of Polyphosphate against Prevotella intermedia in Planktonic Phase and Biofilm

    PubMed Central

    Jang, Eun-Young; Kim, Minjung; Noh, Mi Hee

    2015-01-01

    Polyphosphate (polyP) has gained a wide interest in the food industry due to its potential as a decontaminating agent. In this study, we examined the effect of sodium tripolyphosphate (polyP3; Na5P3O10) against planktonic and biofilm cells of Prevotella intermedia, a major oral pathogen. The MIC of polyP3 against P. intermedia ATCC 49046 determined by agar dilution method was 0.075%, while 0.05% polyP3 was bactericidal against P. intermedia in time-kill analysis performed using liquid medium. A crystal violet binding assay for the assessment of biofilm formation by P. intermedia showed that sub-MICs of polyP3 significantly decreased biofilm formation. Under the scanning electron microscope, decreased numbers of P. intermedia cells forming the biofilms were observed when the bacterial cells were incubated with 0.025% or higher concentrations of polyP3. Assessment of biofilm viability with LIVE/DEAD staining and viable cell count methods showed that 0.05% or higher concentrations of polyP3 significantly decreased the viability of the preformed biofilms in a concentration-dependent manner. The zone sizes of alpha-hemolysis formed on horse blood agar produced by P. intermedia were decreased in the presence of polyP3. The expression of the genes encoding hemolysins and the genes of the hemin uptake (hmu) locus was downregulated by polyP3. Collectively, our results show that polyP is an effective antimicrobial agent against P. intermedia in biofilms as well as planktonic phase, interfering with the process of hemin acquisition by the bacterium. PMID:26596937

  3. Can endoscopic ultrasonography differentiate nonneoplastic from neoplastic gallbladder polyps?

    PubMed

    Akatsu, Tomotaka; Aiura, Koichi; Shimazu, Motohide; Ueda, Masakazu; Wakabayashi, Go; Tanabe, Minoru; Kawachi, Shigeyuki; Kitajima, Masaki

    2006-02-01

    The present study aimed to clarify the endoscopic ultrasonography (EUS) features of nonneoplastic (cholesterol polyps and adenomyomatosis) and neoplastic (adenoma and adenocarcinoma) gallbladder polyps and to evaluate the effectiveness and limitation of EUS in the differential diagnosis of these lesions. We retrospectively compared EUS images with histologic findings in 29 surgical cases with gallbladder polyps with a diameter of 10 to 20 mm. Those cases were indicated for surgery based on the findings of a sessile appearance, a solitary lesion, low echogenicity, and/or a lobulated surface. Six of 10 cholesterol polyps were atypically seen as partially or completely hypoechoic due to predominant proliferation of glandular epithelia. Nine of 10 cholesterol polyps demonstrated an aggregation of hyperechoic spots, which represented multiple granules of cholesterosis. All adenomyomatoses (n = 10) showed multiple microcysts, which corresponded to proliferated Rokitansky-Aschoff sinuses. However, three of nine neoplastic lesions (three adenomas and six adenocarcinomas) showed one of these signs due to concomitant cholesterosis (n = 2) or proliferated Rokitansky-Aschoff sinuses (n = 1). In conclusion, 69% (20/29) of gallbladder polyps larger than 10 mm that were preoperatively suspected of malignancy were nonneoplastic. An aggregation of hyperechoic spots and multiple microcysts are considered to be important predictive factors for cholesterol polyps and adenomyomatosis, respectively. However, we should caution that these findings can also occur in neoplastic polyps when they contain a concomitant nonneoplastic component (cholesterosis or proliferated Rokitansky-Aschoff sinuses).

  4. A new exploration for gallbladder polyps: gallbladder polypectomy by endolap technique.

    PubMed

    Wang, JingMin; Tan, YuYan; Zhao, Gang; Wang, Dong; Ji, ZhenLing

    2014-12-01

    Abstract Gallbladder polyps are most commonly treated with cholecystectomy, which is associated with various complications. For benign disease, preserving the gallbladder is preferable. Since 1994, we have been exploring percutaneous polypectomy and have recently developed an improved new technique. This study reports a new endoscopic-laparoscopic (Endolap) technique for the removal of polyps and the preservation of the gallbladder. Nine Chinese mini-pigs were used to observe mucosal regeneration. Microwaves of 50-70 mA for 9 seconds were safe, and the gallbladder mucosa of pigs recovered to nearly normal 2 weeks later. In the clinical cases, 60 patients with gallbladder polyps were studied. With the patient under general anesthesia, each polyp stem was coagulated, and then the polyp was removed. All procedures were successful at between 60 and 135 minutes. The success rate was 93.33% (56/60). A retrospective analysis was conducted to assess the recovery of gallbladder function. All patients were followed up and symptom-free, without recurrence of the polyps; 3 months after the operation, the volume and contraction of the gallbladder recovered to preoperative levels. Thus the Endolap technique is reliable for removing benign gallbladder polyps and is applicable to a wider range of clinical situations than percutaneous polypectomy.

  5. Polyphosphate is a key factor for cell survival after DNA damage in eukaryotic cells.

    PubMed

    Bru, Samuel; Samper-Martín, Bàrbara; Quandt, Eva; Hernández-Ortega, Sara; Martínez-Laínez, Joan M; Garí, Eloi; Rafel, Marta; Torres-Torronteras, Javier; Martí, Ramón; Ribeiro, Mariana P C; Jiménez, Javier; Clotet, Josep

    2017-09-01

    Cells require extra amounts of dNTPs to repair DNA after damage. Polyphosphate (polyP) is an evolutionary conserved linear polymer of up to several hundred inorganic phosphate (Pi) residues that is involved in many functions, including Pi storage. In the present article, we report on findings demonstrating that polyP functions as a source of Pi when required to sustain the dNTP increment essential for DNA repair after damage. We show that mutant yeast cells without polyP produce less dNTPs upon DNA damage and that their survival is compromised. In contrast, when polyP levels are ectopically increased, yeast cells become more resistant to DNA damage. More importantly, we show that when polyP is reduced in HEK293 mammalian cell line cells and in human dermal primary fibroblasts (HDFa), these cells become more sensitive to DNA damage, suggesting that the protective role of polyP against DNA damage is evolutionary conserved. In conclusion, we present polyP as a molecule involved in resistance to DNA damage and suggest that polyP may be a putative target for new approaches in cancer treatment or prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Stomach Polyps

    MedlinePlus

    ... polyps are: Chronic stomach inflammation. Also known as gastritis, this condition can cause the formation of hyperplastic ... pylori) bacteria are a common cause of the gastritis that contributes to hyperplastic polyps and adenomas. Familial ...

  7. FXIa and platelet polyphosphate as therapeutic targets during human blood clotting on collagen/tissue factor surfaces under flow.

    PubMed

    Zhu, Shu; Travers, Richard J; Morrissey, James H; Diamond, Scott L

    2015-09-17

    Factor XIIa (FXIIa) and factor XIa (FXIa) contribute to thrombosis in animal models, whereas platelet-derived polyphosphate (polyP) may potentiate contact or thrombin-feedback pathways. The significance of these mediators in human blood under thrombotic flow conditions on tissue factor (TF) -bearing surfaces remains inadequately resolved. Human blood (corn trypsin inhibitor treated [4 μg/mL]) was tested by microfluidic assay for clotting on collagen/TF at TF surface concentration ([TF]wall) from ∼0.1 to 2 molecules per μm(2). Anti-FXI antibodies (14E11 and O1A6) or polyP-binding protein (PPXbd) were used to block FXIIa-dependent FXI activation, FXIa-dependent factor IX (FIX) activation, or platelet-derived polyP, respectively. Fibrin formation was sensitive to 14E11 at 0 to 0.1 molecules per µm(2) and sensitive to O1A6 at 0 to 0.2 molecules per µm(2). However, neither antibody reduced fibrin generation at ∼2 molecules per µm(2) when the extrinsic pathway became dominant. Interestingly, PPXbd reduced fibrin generation at low [TF]wall (0.1 molecules per µm(2)) but not at zero or high [TF]wall, suggesting a role for polyP distinct from FXIIa activation and requiring low extrinsic pathway participation. Regardless of [TF]wall, PPXbd enhanced fibrin sensitivity to tissue plasminogen activator and promoted clot retraction during fibrinolysis concomitant with an observed PPXbd-mediated reduction of fibrin fiber diameter. This is the first detection of endogenous polyP function in human blood under thrombotic flow conditions. When triggered by low [TF]wall, thrombosis may be druggable by contact pathway inhibition, although thrombolytic susceptibility may benefit from polyP antagonism regardless of [TF]wall. © 2015 by The American Society of Hematology.

  8. Two strictly polyphosphate-dependent gluco(manno)kinases from diazotrophic Cyanobacteria with potential to phosphorylate hexoses from polyphosphates.

    PubMed

    Albi, Tomás; Serrano, Aurelio

    2015-05-01

    The single-copy genes encoding putative polyphosphate-glucose phosphotransferases (PPGK, EC 2.7.1.63) from two nitrogen-fixing Cyanobacteria, Nostoc sp. PCC7120 and Nostoc punctiforme PCC73102, were cloned and functionally characterized. In contrast to their actinobacterial counterparts, the cyanobacterial PPGKs have shown the ability to phosphorylate glucose using strictly inorganic polyphosphates (polyP) as phosphoryl donors. This has proven to be an economically attractive reagent in contrast to the more costly ATP. Cyanobacterial PPGKs had a higher affinity for medium-long-sized polyP (greater than ten phosphoryl residues). Thus, longer polyP resulted in higher catalytic efficiency. Also in contrast to most their homologs in Actinobacteria, both cyanobacterial PPGKs exhibited a modest but significant polyP-mannokinase activity as well. Specific activities were in the range of 180-230 and 2-3 μmol min(-1) mg(-1) with glucose and mannose as substrates, respectively. No polyP-fructokinase activity was detected. Cyanobacterial PPGKs required a divalent metal cofactor and exhibited alkaline pH optima (approx. 9.0) and a remarkable thermostability (optimum temperature, 45 °C). The preference for Mg(2+) was noted with an affinity constant of 1.3 mM. Both recombinant PPGKs are homodimers with a subunit molecular mass of ca. 27 kDa. Based on database searches and experimental data from Southern blots and activity assays, closely related PPGK homologs appear to be widespread among unicellular and filamentous mostly nitrogen-fixing Cyanobacteria. Overall, these findings indicate that polyP may be metabolized in these photosynthetic prokaryotes to yield glucose (or mannose) 6-phosphate. They also provide evidence for a novel group-specific subfamily of strictly polyP-dependent gluco(manno)kinases with ancestral features and high biotechnological potential, capable of efficiently using polyP as an alternative and cheap source of energy-rich phosphate instead of costly ATP. Finally, these results could shed new light on the evolutionary origin of sugar kinases.

  9. Imaging for Polyps and Leiomyomas in Women With Abnormal Uterine Bleeding: A Systematic Review.

    PubMed

    Maheux-Lacroix, Sarah; Li, Fiona; Laberge, Philippe Y; Abbott, Jason

    2016-12-01

    To evaluate the accuracy of saline infusion sonohysterography in comparison with transvaginal ultrasonography for diagnosing polyps and submucosal leiomyomas in women with abnormal uterine bleeding. We searched the databases MEDLINE, EMBASE, CENTRAL, and ClinicalTrials.gov as well as citations and reference lists to the end of November 2015. Two authors screened 5,347 citations for eligibility. We included randomized controlled trials or prospective cohort studies published in English, assessing the accuracy of saline infusion sonohysterography and transvaginal ultrasonography for diagnosing polyps and submucosal leiomyomas in women with abnormal uterine bleeding. We considered studies using histopathologic specimens obtained at either hysteroscopy or hysterectomy as criterion standard. Twenty-five studies were eligible. Two authors extracted data and assessed the quality of included studies. Bivariate random-effects models were used to compare the different tests and evaluate sources of heterogeneity. Saline infusion sonohysterography was superior to transvaginal ultrasonography with pooled sensitivity and specificity of 0.92 and 0.89 compared with 0.64 and 0.90, respectively (P<.001). Transvaginal ultrasound sensitivity for diagnosing polyps was particularly low (0.51). Saline infusion sonohysterography was also compared with hysteroscopy in seven studies and had similar sensitivity but inferior specificity (0.93 and 0.83 compared with 0.95 and 0.90, respectively, P=.007). All three procedures were well-tolerated by women. Saline infusion sonohysterography was successfully completed in 95% of women. Technical variations such as the use of balloon catheters were not found to affect diagnostic accuracy. Transvaginal ultrasonography lacks sensitivity to be used alone to exclude the presence of polyps and leiomyomas in women with abnormal uterine bleeding. Although less specific than hysteroscopy, saline infusion sonohysterography offers a similar detection rate and permits concomitant visualization of the ovaries and myometrium. Cost, convenience, and tolerability of different imaging techniques require further evaluation. PROSPERO International prospective register of systematic reviews, http://www.crd.york.ac.uk/PROSPERO, CRD42016034005.

  10. 75 FR 16123 - Dave & Buster’s, Inc.; Analysis of Proposed Consent Order to Aid Public Comment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-31

    ... computer networks or to conduct security investigations, such as by employing an intrusion detection system and monitoring system logs; (b) failed to adequately restrict third-party access to its networks, such... reasonable and appropriate security for personal information on its computer networks. Among other things...

  11. Computer aided detection of ureteral stones in thin slice computed tomography volumes using Convolutional Neural Networks.

    PubMed

    Längkvist, Martin; Jendeberg, Johan; Thunberg, Per; Loutfi, Amy; Lidén, Mats

    2018-06-01

    Computed tomography (CT) is the method of choice for diagnosing ureteral stones - kidney stones that obstruct the ureter. The purpose of this study is to develop a computer aided detection (CAD) algorithm for identifying a ureteral stone in thin slice CT volumes. The challenge in CAD for urinary stones lies in the similarity in shape and intensity of stones with non-stone structures and how to efficiently deal with large high-resolution CT volumes. We address these challenges by using a Convolutional Neural Network (CNN) that works directly on the high resolution CT volumes. The method is evaluated on a large data base of 465 clinically acquired high-resolution CT volumes of the urinary tract with labeling of ureteral stones performed by a radiologist. The best model using 2.5D input data and anatomical information achieved a sensitivity of 100% and an average of 2.68 false-positives per patient on a test set of 88 scans. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Mutual information-based template matching scheme for detection of breast masses: from mammography to digital breast tomosynthesis

    PubMed Central

    Mazurowski, Maciej A; Lo, Joseph Y; Harrawood, Brian P; Tourassi, Georgia D

    2011-01-01

    Development of a computational decision aid for a new medical imaging modality typically is a long and complicated process. It consists of collecting data in the form of images and annotations, development of image processing and pattern recognition algorithms for analysis of the new images and finally testing of the resulting system. Since new imaging modalities are developed more rapidly than ever before, any effort for decreasing the time and cost of this development process could result in maximizing the benefit of the new imaging modality to patients by making the computer aids quickly available to radiologists that interpret the images. In this paper, we make a step in this direction and investigate the possibility of translating the knowledge about the detection problem from one imaging modality to another. Specifically, we present a computer-aided detection (CAD) system for mammographic masses that uses a mutual information-based template matching scheme with intelligently selected templates. We presented principles of template matching with mutual information for mammography before. In this paper, we present an implementation of those principles in a complete computer-aided detection system. The proposed system, through an automatic optimization process, chooses the most useful templates (mammographic regions of interest) using a large database of previously collected and annotated mammograms. Through this process, the knowledge about the task of detecting masses in mammograms is incorporated in the system. Then we evaluate whether our system developed for screen-film mammograms can be successfully applied not only to other mammograms but also to digital breast tomosynthesis (DBT) reconstructed slices without adding any DBT cases for training. Our rationale is that since mutual information is known to be a robust intermodality image similarity measure, it has high potential of transferring knowledge between modalities in the context of the mass detection task. Experimental evaluation of the system on mammograms showed competitive performance compared to other mammography CAD systems recently published in the literature. When the system was applied “as-is” to DBT, its performance was notably worse than that for mammograms. However, with a simple additional preprocessing step, the performance of the system reached levels similar to that obtained for mammograms. In conclusion, the presented CAD system not only performed competitively on screen-film mammograms but it also performed robustly on DBT showing that direct transfer of knowledge across breast imaging modalities for mass detection is in fact possible. PMID:21554985

  13. Computer-aided detection of breast lesions in DCE-MRI using region growing based on fuzzy C-means clustering and vesselness filter

    NASA Astrophysics Data System (ADS)

    B. Shokouhi, Shahriar; Fooladivanda, Aida; Ahmadinejad, Nasrin

    2017-12-01

    A computer-aided detection (CAD) system is introduced in this paper for detection of breast lesions in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). The proposed CAD system firstly compensates motion artifacts and segments the breast region. Then, the potential lesion voxels are detected and used as the initial seed points for the seeded region-growing algorithm. A new and robust region-growing algorithm incorporating with Fuzzy C-means (FCM) clustering and vesselness filter is proposed to segment any potential lesion regions. Subsequently, the false positive detections are reduced by applying a discrimination step. This is based on 3D morphological characteristics of the potential lesion regions and kinetic features which are fed to the support vector machine (SVM) classifier. The performance of the proposed CAD system is evaluated using the free-response operating characteristic (FROC) curve. We introduce our collected dataset that includes 76 DCE-MRI studies, 63 malignant and 107 benign lesions. The prepared dataset has been used to verify the accuracy of the proposed CAD system. At 5.29 false positives per case, the CAD system accurately detects 94% of the breast lesions.

  14. Polyp Prevention Trial

    Cancer.gov

    The primary objective of the Polyp Prevention Trial (PPT) is to determine whether a low fat, high fiber, high vegetable and fruit eating plan will decrease the recurrence of adenomatous polyps of the large bowel.

  15. The expression of 11β-hydroxysteroid dehydrogenase type 1 and 2 in nasal polyp-derived epithelial cells and its possible contribution to glucocorticoid activation in nasal polyp.

    PubMed

    Kook, Jin Ho; Kim, Hyun Jin; Kim, Kyung Won; Park, Se Jin; Kim, Tae Hoon; Lim, Sae Hee; Kang, Sung Hoon; Lee, Sang Hag

    2015-01-01

    The actions of glucocorticoids in target tissues depend on the local metabolism of glucocorticoids catalyzed by 11β hydroxysteroid dehydrogenase (HSD) 1 and 2. Glucocorticoids are the most effective anti-inflammatory drugs in the treatment of nasal polyps. However, the mechanisms that underlie the anti-inflammatory effects are unclear. The present study analyzed the expression of 11β-HSD1, 11β-HSD2, and steroidogenic enzymes (cytochrome P450, family 11, subfamily B, polypeptide 1 [CYP11B1]; cytochrome P450, family 11, subfamily A, polypeptide 1 [CYP11A1]) in nasal polyp tissues, and endogenous cortisol levels in nasal polyp-derived epithelial cells. The expression levels and distribution pattern of 11β-HSD1, 11β-HSD2, CYP11B1, and CYP11A1 were determined in nasal polyp tissues or nasal polyp-derived epithelial cells by using real-time polymerase chain reaction, Western blot, and immunohistochemistry testing. The expression levels of cortisol by using enzyme-linked immunosorbent assay were determined in cultured polyp-derived epithelial cells treated with adrenocorticotrophic hormone (ACTH), 11β-HSD1 inhibitor, or small interfering ribonucleic acid technique. The effect of glucocorticoids on the expression levels of these enzymes was investigated in cultured cells. Expressed in nasal polyp tissues and nasal polyp-derived epithelial cells were 11β-HSD1, 11β-HSD2, CYP11B1, and CYP11A1. Cortisol production in cultured epithelial cells was decreased in cells treated with 11β-HSD1 small interfering ribonucleic acid or inhibitor, compared with nontreated cells. Cultured cells treated with adrenocorticotropic hormone induced increased cortisol production. 11β-HSD1 expression levels were upregulated in cells treated with glucocorticoid. Analysis of these results indicated that 11β-HSD1 expressed in polyp-derived epithelial cells may be involved in the anti-inflammatory function of glucocorticoid in the treatment of nasal polyps, which contributes to increased levels of endogenous cortisol.

  16. Pre-exposure to simultaneous, but not individual, climate change stressors limits acclimation capacity of Irukandji jellyfish polyps to predicted climate scenarios

    NASA Astrophysics Data System (ADS)

    Klein, Shannon G.; Pitt, Kylie A.; Carroll, Anthony R.

    2017-09-01

    Researchers have investigated the immediate effects of end-of-century climate change scenarios on many marine species, yet it remains unclear whether we can reliably predict how marine species may respond to future conditions because biota may become either more or less resistant over time. Here, we examined the role of pre-exposure to elevated temperature and reduced pH in mitigating the potential negative effects of future ocean conditions on polyps of a dangerous Irukandji jellyfish Alatina alata. We pre-exposed polyps to elevated temperature (28 °C) and reduced pH (7.6), in a full factorial experiment that ran for 14 d. We secondarily exposed original polyps and their daughter polyps to either current (pH 8.0, 25 °C) or future conditions (pH 7.6, 28 °C) for a further 34 d to assess potential phenotypic plastic responses and whether asexual offspring could benefit from parental pre-exposure. Polyp fitness was characterised as asexual reproduction, respiration, feeding, and protein concentrations. Pre-exposure to elevated temperature alone partially mitigated the negative effects of future conditions on polyp fitness, while pre-exposure to reduced pH in isolation completely mitigated the negative effects of future conditions on polyp fitness. Pre-exposure to the dual stressors, however, reduced fitness under future conditions relative to those in the control treatment. Under future conditions, polyps had higher respiration rates regardless of the conditions they were pre-exposed to, suggesting that metabolic rates will be higher under future conditions. Parent and daughter polyps responded similarly to the various treatments tested, demonstrating that parental pre-exposure did not confer any benefit to asexual offspring under future conditions. Importantly, we demonstrate that while pre-exposure to the stressors individually may allow Irukandji polyps to acclimate over short timescales, the stressors are unlikely to occur in isolation in the long term, and thus, warming and acidification in parallel may prevent polyp populations from acclimating to future ocean conditions.

  17. Juvenile polyposis syndrome

    PubMed Central

    Hsiao, Yi-Han; Wei, Chin-Hung; Chang, Szu-Wen; Chang, Lung; Fu, Yu-Wei; Lee, Hung-Chang; Liu, Hsuan-Liang; Yeung, Chun-Yan

    2016-01-01

    Abstract Background: Juvenile polyposis syndrome, a rare disorder in children, is characterized with multiple hamartomatous polyps in alimentary tract. A variety of manifestations include bleeding, intussusception, or polyp prolapse. In this study, we present an 8-month-old male infant of juvenile polyposis syndrome initially presenting with chronic anemia. To the best of our knowledge, this is the youngest case reported in the literature. Methods: We report a rare case of an 8-month-old male infant who presented with chronic anemia and gastrointestinal bleeding initially. Panendoscopy and abdominal computed tomography showed multiple polyposis throughout the entire alimentary tract leading to intussusception. Technetium-99m-labeled red blood cell (RBC) bleeding scan revealed the possibility of gastrointestinal tract bleeding in the jejunum. Histopathological examination on biopsy samples showed Peutz-Jeghers syndrome was excluded, whereas the diagnosis of juvenile polyposis syndrome was established. Results: Enteroscopic polypectomy is the mainstay of the treatment. However, polyps recurred and occupied the majority of the gastrointestinal tract in 6 months. Supportive management was given. The patient expired for severe sepsis at the age of 18 months. Conclusion: Juvenile polyposis syndrome is an inherited disease, so it is not possible to prevent it. Concerning of its poor outcome and high mortality rate, it is important that we should increase awareness and education of the parents at its earliest stages. PMID:27631205

  18. Contrast-enhanced ultrasonography for the detection of joint vascularity in arthritis--subjective grading versus computer-aided objective quantification.

    PubMed

    Klauser, A S; Franz, M; Bellmann Weiler, R; Gruber, J; Hartig, F; Mur, E; Wick, M C; Jaschke, W

    2011-12-01

    To compare joint inflammation assessment using subjective grading of power Doppler ultrasonography (PDUS) and contrast-enhanced ultrasonography (CEUS) versus computer-aided objective CEUS quantification. 37 joints of 28 patients with arthritis of different etiologies underwent B-mode ultrasonography, PDUS, and CEUS using a second-generation contrast agent. Synovial thickness, extent of vascularized pannus and intensity of vascularization were included in a 4-point PDUS and CEUS grading system. Subjective CEUS and PDUS scores were compared to computer-aided objective CEUS quantification using Qontrast® software for the calculation of the signal intensity (SI) and the ratio of SI for contrast enhancement. The interobserver agreement for subjective scoring was good to excellent (κ = 0.8 - 1.0; P < 0.0001). Computer-aided objective CEUS quantification correlated statistically significantly with subjective CEUS (P < 0.001) and PDUS grading (P < 0.05). The Qontrast® SI ratio correlated with subjective CEUS (P < 0.02) and PDUS grading (P < 0.03). Clinical activity did not correlate with vascularity or synovial thickening (P = N. S.) and no correlation between synovial thickening and vascularity extent could be found, neither using PDUS nor CEUS (P = N. S.). Both subjective CEUS grading and objective CEUS quantification are valuable for assessing joint vascularity in arthritis and computer-aided CEUS quantification may be a suitable objective tool for therapy follow-up in arthritis. © Georg Thieme Verlag KG Stuttgart · New York.

  19. A role for the epidermal growth factor receptor signaling in development of intestinal serrated polyps in mice and humans.

    PubMed

    Bongers, Gerold; Muniz, Luciana R; Pacer, Michelle E; Iuga, Alina C; Thirunarayanan, Nanthakumar; Slinger, Erik; Smit, Martine J; Reddy, E Premkumar; Mayer, Lloyd; Furtado, Glaucia C; Harpaz, Noam; Lira, Sergio A

    2012-09-01

    Epithelial cancers can be initiated by activating mutations in components of the mitogen-activated protein kinase signaling pathway such as v-raf murine sarcoma viral oncogene homolog B1 (BRAF), v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS), or epidermal growth factor receptor (EGFR). Human intestinal serrated polyps are a heterogeneous group of benign lesions, but some progress to colorectal cancer. Tumors that arise from these polyps frequently contain activating mutations in BRAF or KRAS, but little is known about the role of EGFR activation in their development. Polyp samples were obtained from adults during screening colonoscopies at Mount Sinai Hospital in New York. We measured levels of EGFR protein and phosphorylation in human serrated polyps by immunohistochemical and immunoblot analyses. We generated transgenic mice that express the ligand for EGFR, Heparin-binding EGF-like growth factor (HB-EGF), in the intestine. EGFR and the extracellular-regulated kinases (ERK)1/2 were phosphorylated in serrated areas of human hyperplastic polyps (HPPs), sessile serrated adenomas, and traditional serrated adenomas. EGFR and ERK1/2 were phosphorylated in the absence of KRAS or BRAF activating mutations in a subset of HPP. Transgenic expression of the EGFR ligand HB-EGF in the intestines of mice promoted development of small cecal serrated polyps. Mice that expressed a combination of HB-EGF and US28 (a constitutively active, G-protein-coupled receptor that increases processing of HB-EGF from the membrane) rapidly developed large cecal serrated polyps. These polyps were similar to HPPs and had increased phosphorylation of EGFR and ERK1/2 within the serrated epithelium. Administration of pharmacologic inhibitors of EGFR or MAPK to these transgenic mice significantly reduced polyp development. Activation of EGFR signaling in the intestine of mice promotes development of serrated polyps. EGFR signaling also is activated in human HPPs, sessile serrated adenomas, and traditional serrated adenomas. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

  20. Time Lapse to Colorectal Cancer: Telomere Dynamics Define the Malignant Potential of Polyps.

    PubMed

    Druliner, Brooke R; Ruan, Xiaoyang; Johnson, Ruth; Grill, Diane; O'Brien, Daniel; Lai, Tsung-Po; Rashtak, Shahrooz; Felmlee-Devine, Donna; Washechek-Aletto, Jill; Malykh, Andrei; Smyrk, Thomas; Oberg, Ann; Liu, Hongfang; Shay, Jerry W; Ahlquist, David A; Boardman, Lisa A

    2016-09-01

    Whereas few adenomas become cancer, most colorectal cancers arise from adenomas. Telomere length is a recognized biomarker in multiple cancers, and telomere maintenance mechanisms (TMM) are exploited by malignant cells. We sought to determine whether telomere length and TMM distinguish cancer-associated adenomas from those that are cancer-free. Tissues were identified as cancer-adjacent polyp (CAP)-residual adenoma contiguous with cancer-and cancer-free polyp (CFP)-adenomas without malignancy. Telomere length, TMM, and expression were measured in 102 tissues including peripheral blood leukocytes (PBLs), normal colon epithelium, adenoma, and cancer (in CAP cases) from 31 patients. Telomere length was measured in a separate cohort of 342 PBL from CAP and CFP patients. The mean differences in telomere length between normal and adenoma were greater in CAP than in CFP cases, P=0.001; telomere length in PBL was 91.7 bp greater in CAP than in CFP, P=0.007. Each 100 bp telomere increase was associated with a 1.14 (1.04-1.26) increased odds of being a CAP, P=0.0063. The polyp tissue from CAP patients had shorter telomeres and higher Telomerase reverse transcriptase (hTERT) expression compared with polyps from CFP patients, P=0.05. There was a greater degree of alternative lengthening of telomere (ALT) level difference in CFP polyps than in CAP polyps. The polyp telomere lengths of aggressive CAPs were significantly different from the polyps of non-aggressive CAPs, P=0.01. Adenomas that progress to cancer exhibit distinct telomere length and TMM profiles. We report for the first time that PBL telomeres differ in patients with polyps that become malignant, and therefore may have clinical value in adenoma risk assessment and management.

  1. A case of bilateral vocal fold mucosal bridges, bilateral trans-vocal fold type III sulci vocales, and an intracordal polyp.

    PubMed

    Tan, Melin; Pitman, Michael J

    2011-07-01

    We present a patient with a novel finding of bilateral mucosal bridges, bilateral type III trans-vocal fold sulci vocales, and a vocal fold polyp. Although sulci and mucosal bridges occur in the vocal folds, it is rare to find multiples of these lesions in a single patient, and it is even more uncommon when they occur in conjunction with a vocal fold polyp. To our knowledge, this is the first description of a vocal fold polyp in combination with multiple vocal fold bridges and multiple type III sulci vocales in a single patient. To describe and visually present the diagnosis and treatment of a patient with an intracordal polyp, bilateral mucosal bridges, as well as bilateral type III trans-vocal fold sulci vocales. Presentation of a set of high definition intraoperative photos displaying the extent of the vocal fold lesions and the resection of the intracordal polyp. This patient presented with only 6 months of significant dysphonia. It was felt that the recent change in voice was because of the polyp and not the bridges or sulci vocales. Considering the patient's presentation and the possible morbidity of resection of mucosal bridges and sulci, only the polyp was excised. Postoperatively, the patient's voice returned to his acceptable mild baseline dysphonia, and the benefit has persisted 6 months postoperatively. The combination of bilateral mucosal bridges, bilateral type III sulcus vocalis, and an intracordal polyp in one patient is rare if not novel. Treatment of the polyp alone returned the patient's voice to his lifelong baseline of mild dysphonia. Copyright © 2011 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  2. Changing pathological diagnosis from hyperplastic polyp to sessile serrated adenoma: systematic review and meta-analysis.

    PubMed

    Niv, Yaron

    2017-12-01

    The WHO published a new classification of colonic polyps in 2010, including the group of serrated polyps, which can be divided into hyperplastic polyps (HP), traditional serrated adenomas, and sessile serrated adenomas (SSA) or polyps. To assess the rate of re-diagnosis of HP to SSA and to look for possible predictors for changing the diagnosis. English Medical literature searches were performed for 'reassessment' OR 'reclassification' AND 'hyperplastic polyp' OR 'sessile serrated adenoma' till 31 January 2017. PRISMA guidelines for systematic reviews were followed. Studies that included a precise re-diagnosis of HP into SSA were included. We also looked for predictors of SSA diagnosis such as polyp location and size, patient sex and age, and synchronous advanced adenoma. Altogether, we found 220 eligible studies; 212 were excluded as they did not fulfill the inclusion criteria and we were left with eight studies including 2625 patients. The odds ratio for the number of polyps with changed pathological diagnosis from HP to SSA was 0.112 with 95% confidence interval (CI): 0.099-0.126 (P<0.0001) or 11.2%. Heterogeneity between studies was significant with Q=199.4, d.f. (Q)=9, P<0.0001, and I=95.486%. The odds ratio for changing the pathological diagnosis from HP to SSA for polyp proximal location and polyp size more than 5 mm were 4.401, 95% CI: 2.784-6.958, P<0.0001, and 8.336, 95% CI: 4.963-15.571, P<0.0001, respectively. Endoscopists and pathologists should be aware of the SSA diagnosis when finding HPs larger than 5 mm in the right colon. The diagnosis of HP in these cases should be reassessed by experienced gastrointestinal pathologists.

  3. Copper tolerance of the thermoacidophilic archaeon Sulfolobus metallicus: possible role of polyphosphate metabolism.

    PubMed

    Remonsellez, Francisco; Orell, Alvaro; Jerez, Carlos A

    2006-01-01

    It has been postulated that inorganic polyphosphate (polyP) and transport of metal-phosphate complexes could participate in heavy metal tolerance in some bacteria. To study if such a system exists in archaea, the presence of polyP was determined by the electron energy loss spectroscopy (EELS) procedure and quantified by using specific enzymic methods in Sulfolobus acidocaldarius, Sulfolobus metallicus and Sulfolobus solfataricus. All three micro-organisms synthesized polyP during growth, but only S. metallicus greatly accumulated polyP granules. The differences in the capacity to accumulate polyP between these archaea may reflect adaptive responses to their natural environment. Thus, S. metallicus could grow in and tolerate up to 200 mM copper sulfate, with a concomitant decrease in its polyP levels with increasing copper concentrations. On the other hand, S. solfataricus could not grow in or tolerate more than 1-5 mM copper sulfate, most likely due to its low levels of polyP. Shifting S. metallicus cells to copper sulfate concentrations up to 100 mM led to a rapid increase in their exopolyphosphatase (PPX) activity which was concomitant in time with a decrease in their polyP levels and a stimulation of phosphate efflux. Furthermore, copper in the range of 10 microM greatly stimulated PPX activity in cell-free extracts from S. metallicus. The results strongly suggest that a metal tolerance mechanism mediated through polyP is functional in members of the genus Sulfolobus. This ability to accumulate and hydrolyse polyP may play an important role not only in the survival of these micro-organisms in sulfidic mineral environments containing high toxic metals concentrations, but also in their applications in biomining.

  4. In Vitro Effects of Polyphosphate against Prevotella intermedia in Planktonic Phase and Biofilm.

    PubMed

    Jang, Eun-Young; Kim, Minjung; Noh, Mi Hee; Moon, Ji-Hoi; Lee, Jin-Yong

    2016-02-01

    Polyphosphate (polyP) has gained a wide interest in the food industry due to its potential as a decontaminating agent. In this study, we examined the effect of sodium tripolyphosphate (polyP3; Na5P3O10) against planktonic and biofilm cells of Prevotella intermedia, a major oral pathogen. The MIC of polyP3 against P. intermedia ATCC 49046 determined by agar dilution method was 0.075%, while 0.05% polyP3 was bactericidal against P. intermedia in time-kill analysis performed using liquid medium. A crystal violet binding assay for the assessment of biofilm formation by P. intermedia showed that sub-MICs of polyP3 significantly decreased biofilm formation. Under the scanning electron microscope, decreased numbers of P. intermedia cells forming the biofilms were observed when the bacterial cells were incubated with 0.025% or higher concentrations of polyP3. Assessment of biofilm viability with LIVE/DEAD staining and viable cell count methods showed that 0.05% or higher concentrations of polyP3 significantly decreased the viability of the preformed biofilms in a concentration-dependent manner. The zone sizes of alpha-hemolysis formed on horse blood agar produced by P. intermedia were decreased in the presence of polyP3. The expression of the genes encoding hemolysins and the genes of the hemin uptake (hmu) locus was downregulated by polyP3. Collectively, our results show that polyP is an effective antimicrobial agent against P. intermedia in biofilms as well as planktonic phase, interfering with the process of hemin acquisition by the bacterium. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  5. Pathologic observations of the duodenum in 615 consecutive duodenal specimens: I. benign lesions

    PubMed Central

    Terada, Tadashi

    2012-01-01

    The author investigated histopathology of 615 consecutive duodenal specimens in our pathology laboratory. Computer search of the duodenal lesions was performed. Review of histological slides was done, when appropriate. The duodenal specimens were composed of 567 benign lesions and 48 malignant lesions. The 567 benign lesions were composed of chronic non-specific duodenitis in 334 cases (60.0%), duodenal ulcer in 101 cases (17,8%), heterotopic gastric mucosa in 81 cases (14.3%), hyperplastic polyp in 16 cases (2.8%), Brunner's gland hyperplasia in 14 cases (2.5%), Brunner's gland adenoma in 8 cases (1.4%), lymphoid polyp in 5 cases (0.8%), tubular adenoma in 4 cases (0.7%), lymphangioma in 2 cases (0.4%), endocrine nests in 1 case (0.2%), and amyloidosis in 1 case (0.2%). The chronic non-specific duodenitis was characterized by edema and lymphocytic infiltration. The duodenal ulcer was characterized by exudate, necrosis, granulation tissue and regenerative epithelium. The heterotopic gastric mucosa consisted of two types: one was composed of only foveolar epithelium (n=21) and another foveolar epithelium and fundic glands (n=60). Hyperplastic polyp was characterized by proliferation of gastric foveolar-like epithelium. The Brunner's gland hyperplasia was characterized by hyperplastic proliferation of the gland. The Brunner gland adenoma was characterized by neoplastic proliferation of the gland. The lymphoid polyp was characterized by large lymph follicles with large germinal centers. The tubular adenoma was characterized by adenomatous proliferation of intestinal epithelium, similar to colon adenoma. The lymphangioma was characterized by submucosal cavernous proliferation of lymphatics. The endocrine cell nests were characterized by non-neoplasmic proliferation of neuroendocrine cells. The amyloidosis was characterized by deposition of amorphous materials positive with Congo-red stain. PMID:22295146

  6. Pathologic observations of the duodenum in 615 consecutive duodenal specimens: I. benign lesions.

    PubMed

    Terada, Tadashi

    2012-01-01

    The author investigated histopathology of 615 consecutive duodenal specimens in our pathology laboratory. Computer search of the duodenal lesions was performed. Review of histological slides was done, when appropriate. The duodenal specimens were composed of 567 benign lesions and 48 malignant lesions. The 567 benign lesions were composed of chronic non-specific duodenitis in 334 cases (60.0%), duodenal ulcer in 101 cases (17,8%), heterotopic gastric mucosa in 81 cases (14.3%), hyperplastic polyp in 16 cases (2.8%), Brunner's gland hyperplasia in 14 cases (2.5%), Brunner's gland adenoma in 8 cases (1.4%), lymphoid polyp in 5 cases (0.8%), tubular adenoma in 4 cases (0.7%), lymphangioma in 2 cases (0.4%), endocrine nests in 1 case (0.2%), and amyloidosis in 1 case (0.2%). The chronic non-specific duodenitis was characterized by edema and lymphocytic infiltration. The duodenal ulcer was characterized by exudate, necrosis, granulation tissue and regenerative epithelium. The heterotopic gastric mucosa consisted of two types: one was composed of only foveolar epithelium (n=21) and another foveolar epithelium and fundic glands (n=60). Hyperplastic polyp was characterized by proliferation of gastric foveolar-like epithelium. The Brunner's gland hyperplasia was characterized by hyperplastic proliferation of the gland. The Brunner gland adenoma was characterized by neoplastic proliferation of the gland. The lymphoid polyp was characterized by large lymph follicles with large germinal centers. The tubular adenoma was characterized by adenomatous proliferation of intestinal epithelium, similar to colon adenoma. The lymphangioma was characterized by submucosal cavernous proliferation of lymphatics. The endocrine cell nests were characterized by non-neoplasmic proliferation of neuroendocrine cells. The amyloidosis was characterized by deposition of amorphous materials positive with Congo-red stain.

  7. High-definition endoscopy with digital chromoendoscopy for histologic prediction of distal colorectal polyps.

    PubMed

    Rath, Timo; Tontini, Gian E; Nägel, Andreas; Vieth, Michael; Zopf, Steffen; Günther, Claudia; Hoffman, Arthur; Neurath, Markus F; Neumann, Helmut

    2015-10-22

    Distal diminutive colorectal polyps are common and accurate endoscopic prediction of hyperplastic or adenomatous polyp histology could reduce procedural time, costs and potential risks associated with the resection. Within this study we assessed whether digital chromoendoscopy can accurately predict the histology of distal diminutive colorectal polyps according to the ASGE PIVI statement. In this prospective cohort study, 224 consecutive patients undergoing screening or surveillance colonoscopy were included. Real time histology of 121 diminutive distal colorectal polyps was evaluated using high-definition endoscopy with digital chromoendoscopy and the accuracy of predicting histology with digital chromoendoscopy was assessed. The overall accuracy of digital chromoendoscopy for prediction of adenomatous polyp histology was 90.1 %. Sensitivity, specificity, positive and negative predictive values were 93.3, 88.7, 88.7, and 93.2 %, respectively. In high-confidence predictions, the accuracy increased to 96.3 % while sensitivity, specificity, positive and negative predictive values were calculated as 98.1, 94.4, 94.5, and 98.1 %, respectively. Surveillance intervals with digital chromoendoscopy were correctly predicted with >90 % accuracy. High-definition endoscopy in combination with digital chromoendoscopy allowed real-time in vivo prediction of distal colorectal polyp histology and is accurate enough to leave distal colorectal polyps in place without resection or to resect and discard them without pathologic assessment. This approach has the potential to reduce costs and risks associated with the redundant removal of diminutive colorectal polyps. ClinicalTrials NCT02217449.

  8. Copper tolerance mediated by polyphosphate degradation and low-affinity inorganic phosphate transport system in Escherichia coli.

    PubMed

    Grillo-Puertas, Mariana; Schurig-Briccio, Lici Ariane; Rodríguez-Montelongo, Luisa; Rintoul, María Regina; Rapisarda, Viviana Andrea

    2014-03-19

    Metal tolerance in bacteria has been related to polyP in a model in which heavy metals stimulate the polymer hydrolysis, forming metal-phosphate complexes that are exported. As previously described in our laboratory, Escherichia coli cells grown in media containing a phosphate concentration >37 mM maintained an unusually high polyphosphate (polyP) level in stationary phase. The aim of the present work was to evaluate the influence of polyP levels as the involvement of low-affinity inorganic phosphate transport (Pit) system in E. coli copper tolerance. PolyP levels were modulated by the media phosphate concentration and/or using mutants in polyP metabolism. Stationary phase wild-type cells grown in high phosphate medium were significantly more tolerant to copper than those grown in sufficient phosphate medium. Copper addition to tolerant cells induced polyP degradation by PPX (an exopolyphosphatase), phosphate efflux and membrane polarization. ppk-ppx- (unable to synthesize/degrade polyP), ppx- (unable to degrade polyP) and Pit system mutants were highly sensitive to metal even in high phosphate media. In exponential phase, CopA and polyP-Pit system would act simultaneously to detoxify the metal or one could be sufficient to safeguard the absence of the other. Our results support a mechanism for copper detoxification in exponential and stationary phases of E. coli, involving Pit system and degradation of polyP. Data reflect the importance of the environmental phosphate concentration in the regulation of the microbial physiological state.

  9. Artificial substrates preference for proliferation and immigration in Aurelia aurita (s. l.) polyps

    NASA Astrophysics Data System (ADS)

    Feng, Song; Lin, Jianing; Sun, Song; Zhang, Fang

    2017-01-01

    The increasing amounts of artificial marine substrates, in many parts of the world have been proposed as a potential driver of Aurelia spp. blooms, on account of providing extra habitats for the settlement and the proliferation of the benthic stage (polyps). Previous experiments have mainly focused on the substrate choices of Aurelia spp. planulae. However, substrate preferences for the proliferation and immigration of polyps have not been reported. We monitored the propagation and immigration of Aurelia aurita (s. l.) polyps on two natural and nine artificial substrates at constant temperature (20±0.5°C) and salinity (30±0.5) in beakers and a glass aquarium in the laboratory, respectively. The results showed that, among artificial substrates, the highest number for polyp proliferation and immigration was found on nets, rigid polyvinyl chloride plates (RPVC), and wood. The lowest density of polyps was present on iron plates. Among natural substrates, the asexual reproduction rate of polyps on Patinopecten yessoensis (Jay, 1857) shells was significantly higher than Azumapecten farreri (Jones & Preston, 1904). On the account of the distinction in the roughness, chemical properties and biofilms of these material surfaces, bare artificial or natural substrates discriminatively affect the proliferation and the immigration of Aurelia spp. polyps at laboratory. These observations suggest that, even in the natural environment, different materials and texture may influence the composition and the abundance of the fouling communities and the assemblages of polyps and, indirectly, have effects on the amounts of released medusae.

  10. Colometer: a real-time quality feedback system for screening colonoscopy.

    PubMed

    Filip, Dobromir; Gao, Xuexin; Angulo-Rodríguez, Leticia; Mintchev, Martin P; Devlin, Shane M; Rostom, Alaa; Rosen, Wayne; Andrews, Christopher N

    2012-08-28

    To investigate the performance of a new software-based colonoscopy quality assessment system. The software-based system employs a novel image processing algorithm which detects the levels of image clarity, withdrawal velocity, and level of the bowel preparation in a real-time fashion from live video signal. Threshold levels of image blurriness and the withdrawal velocity below which the visualization could be considered adequate have initially been determined arbitrarily by review of sample colonoscopy videos by two experienced endoscopists. Subsequently, an overall colonoscopy quality rating was computed based on the percentage of the withdrawal time with adequate visualization (scored 1-5; 1, when the percentage was 1%-20%; 2, when the percentage was 21%-40%, etc.). In order to test the proposed velocity and blurriness thresholds, screening colonoscopy withdrawal videos from a specialized ambulatory colon cancer screening center were collected, automatically processed and rated. Quality ratings on the withdrawal were compared to the insertion in the same patients. Then, 3 experienced endoscopists reviewed the collected videos in a blinded fashion and rated the overall quality of each withdrawal (scored 1-5; 1, poor; 3, average; 5, excellent) based on 3 major aspects: image quality, colon preparation, and withdrawal velocity. The automated quality ratings were compared to the averaged endoscopist quality ratings using Spearman correlation coefficient. Fourteen screening colonoscopies were assessed. Adenomatous polyps were detected in 4/14 (29%) of the collected colonoscopy video samples. As a proof of concept, the Colometer software rated colonoscope withdrawal as having better visualization than the insertion in the 10 videos which did not have any polyps (average percent time with adequate visualization: 79% ± 5% for withdrawal and 50% ± 14% for insertion, P < 0.01). Withdrawal times during which no polyps were removed ranged from 4-12 min. The median quality rating from the automated system and the reviewers was 3.45 [interquartile range (IQR), 3.1-3.68] and 3.00 (IQR, 2.33-3.67) respectively for all colonoscopy video samples. The automated rating revealed a strong correlation with the reviewer's rating (ρ coefficient= 0.65, P = 0.01). There was good correlation of the automated overall quality rating and the mean endoscopist withdrawal speed rating (Spearman r coefficient= 0.59, P = 0.03). There was no correlation of automated overall quality rating with mean endoscopists image quality rating (Spearman r coefficient= 0.41, P = 0.15). The results from a novel automated real-time colonoscopy quality feedback system strongly agreed with the endoscopists' quality assessments. Further study is required to validate this approach.

  11. Gastrointestinal tract spindle cell lesions--just like real estate, it's all about location.

    PubMed

    Voltaggio, Lysandra; Montgomery, Elizabeth A

    2015-01-01

    Interpretation of gastrointestinal tract mesenchymal lesions is simplified merely by knowing in which anatomic layer they are usually found. For example, Kaposi sarcoma is detected on mucosal biopsies, whereas inflammatory fibroid polyp is nearly always in the submucosa. Gastrointestinal stromal tumors (GISTs) are generally centered in the muscularis propria. Schwannomas are essentially always in the muscularis propria. Mesenteric lesions are usually found in the small bowel mesentery. Knowledge of the favored layer is even most important in interpreting colon biopsies, as many mesenschymal polyps are encountered in the colon. Although GISTs are among the most common mesenchymal lesions, we will concentrate our discussion on other mesenchymal lesions, some of which are in the differential diagnosis of GIST, and point out some diagnostic pitfalls, particularly in immunolabeling.

  12. Analog Computer-Aided Detection (CAD) information can be more effective than binary marks.

    PubMed

    Cunningham, Corbin A; Drew, Trafton; Wolfe, Jeremy M

    2017-02-01

    In socially important visual search tasks, such as baggage screening and diagnostic radiology, experts miss more targets than is desirable. Computer-aided detection (CAD) programs have been developed specifically to improve performance in these professional search tasks. For example, in breast cancer screening, many CAD systems are capable of detecting approximately 90% of breast cancer, with approximately 0.5 false-positive detections per image. Nevertheless, benefits of CAD in clinical settings tend to be small (Birdwell, 2009) or even absent (Meziane et al., 2011; Philpotts, 2009). The marks made by a CAD system can be "binary," giving the same signal to any location where the signal is above some threshold. Alternatively, a CAD system presents an analog signal that reflects strength of the signal at a location. In the experiments reported, we compare analog and binary CAD presentations using nonexpert observers and artificial stimuli defined by two noisy signals: a visible color signal and an "invisible" signal that informed our simulated CAD system. We found that analog CAD generally yielded better overall performance than binary CAD. The analog benefit is similar at high and low target prevalence. Our data suggest that the form of the CAD signal can directly influence performance. Analog CAD may allow the computer to be more helpful to the searcher.

  13. Computer-Aided Diagnostic (CAD) Scheme by Use of Contralateral Subtraction Technique

    NASA Astrophysics Data System (ADS)

    Nagashima, Hiroyuki; Harakawa, Tetsumi

    We developed a computer-aided diagnostic (CAD) scheme for detection of subtle image findings of acute cerebral infarction in brain computed tomography (CT) by using a contralateral subtraction technique. In our computerized scheme, the lateral inclination of image was first corrected automatically by rotating and shifting. The contralateral subtraction image was then derived by subtraction of reversed image from original image. Initial candidates for acute cerebral infarctions were identified using the multiple-thresholding and image filtering techniques. As the 1st step for removing false positive candidates, fourteen image features were extracted in each of the initial candidates. Halfway candidates were detected by applying the rule-based test with these image features. At the 2nd step, five image features were extracted using the overlapping scale with halfway candidates in interest slice and upper/lower slice image. Finally, acute cerebral infarction candidates were detected by applying the rule-based test with five image features. The sensitivity in the detection for 74 training cases was 97.4% with 3.7 false positives per image. The performance of CAD scheme for 44 testing cases had an approximate result to training cases. Our CAD scheme using the contralateral subtraction technique can reveal suspected image findings of acute cerebral infarctions in CT images.

  14. Report of the Association of Coloproctology of Great Britain and Ireland/British Society of Gastroenterology Colorectal Polyp Working Group: the development of a complex colorectal polyp minimum dataset.

    PubMed

    Chattree, A; Barbour, J A; Thomas-Gibson, S; Bhandari, P; Saunders, B P; Veitch, A M; Anderson, J; Rembacken, B J; Loughrey, M B; Pullan, R; Garrett, W V; Lewis, G; Dolwani, S; Rutter, M D

    2017-01-01

    The management of large non-pedunculated colorectal polyps (LNPCPs) is complex, with widespread variation in management and outcome, even amongst experienced clinicians. Variations in the assessment and decision-making processes are likely to be a major factor in this variability. The creation of a standardized minimum dataset to aid decision-making may therefore result in improved clinical management. An official working group of 13 multidisciplinary specialists was appointed by the Association of Coloproctology of Great Britain and Ireland (ACPGBI) and the British Society of Gastroenterology (BSG) to develop a minimum dataset on LNPCPs. The literature review used to structure the ACPGBI/BSG guidelines for the management of LNPCPs was used by a steering subcommittee to identify various parameters pertaining to the decision-making processes in the assessment and management of LNPCPs. A modified Delphi consensus process was then used for voting on proposed parameters over multiple voting rounds with at least 80% agreement defined as consensus. The minimum dataset was used in a pilot process to ensure rigidity and usability. A 23-parameter minimum dataset with parameters relating to patient and lesion factors, including six parameters relating to image retrieval, was formulated over four rounds of voting with two pilot processes to test rigidity and usability. This paper describes the development of the first reported evidence-based and expert consensus minimum dataset for the management of LNPCPs. It is anticipated that this dataset will allow comprehensive and standardized lesion assessment to improve decision-making in the assessment and management of LNPCPs. Colorectal Disease © 2016 The Association of Coloproctology of Great Britain and Ireland.

  15. Association between Metabolic Syndrome and Gallbladder Polyps in Healthy Korean Adults

    PubMed Central

    Park, Eun Jung; Lee, Hong Soo; Lee, Sang Hwa; Chun, Hye Jin; Kim, Sun Young; Choi, Yu Kyung; Ryu, Hee Jeong

    2013-01-01

    The goal of this study was to evaluate the association between gallbladder (GB) polyps and metabolic syndrome. A total of 5,685 healthy subjects were included, and 485 of these subjects had GB polyps and 744 had metabolic syndrome. In this study, metabolic syndrome was diagnosed according to standards suggested by the AHA/NHLBI ATP III 2005, and abdominal obesity (≥ 90 cm in men and ≥ 85 cm in women for Korean) was diagnosed according to standards set forth by the Korean Society for Study of Obesity. Biphasic logistic regression adjusted for age and gender was used to evaluate the association between metabolic syndrome and GB polyps. Subjects who were male (OR, 1.493; 95% CI, 1.11-2.00) and hepatitis B suface Ag (HBsAg) positive (OR, 1.591; 95% CI, 1.06-2.38) were significantly more likely to have GB polyps. The metabolic syndrome group had a higher risk of GB polyps (OR, 1.315; 95% CI, 1.01-1.69) than the group without metabolic syndrome. In conclusion, subjects who were HBsAg positive and male appear to be associated with the risk of GB polyps. The presence of metabolic syndrome also appears to be associated with the risk of GB polyps in Koreans. PMID:23772152

  16. Association between metabolic syndrome and gallbladder polyps in healthy Korean adults.

    PubMed

    Park, Eun Jung; Lee, Hong Soo; Lee, Sang Hwa; Chun, Hye Jin; Kim, Sun Young; Choi, Yu Kyung; Ryu, Hee Jeong; Shim, Kyung Won

    2013-06-01

    The goal of this study was to evaluate the association between gallbladder (GB) polyps and metabolic syndrome. A total of 5,685 healthy subjects were included, and 485 of these subjects had GB polyps and 744 had metabolic syndrome. In this study, metabolic syndrome was diagnosed according to standards suggested by the AHA/NHLBI ATP III 2005, and abdominal obesity (≥ 90 cm in men and ≥ 85 cm in women for Korean) was diagnosed according to standards set forth by the Korean Society for Study of Obesity. Biphasic logistic regression adjusted for age and gender was used to evaluate the association between metabolic syndrome and GB polyps. Subjects who were male (OR, 1.493; 95% CI, 1.11-2.00) and hepatitis B suface Ag (HBsAg) positive (OR, 1.591; 95% CI, 1.06-2.38) were significantly more likely to have GB polyps. The metabolic syndrome group had a higher risk of GB polyps (OR, 1.315; 95% CI, 1.01-1.69) than the group without metabolic syndrome. In conclusion, subjects who were HBsAg positive and male appear to be associated with the risk of GB polyps. The presence of metabolic syndrome also appears to be associated with the risk of GB polyps in Koreans.

  17. Endoscopic mucosal resection for middle and large colorectal polyps with a double-loop snare.

    PubMed

    Yoshida, Naohisa; Saito, Yutaka; Hirose, Ryohei; Ogiso, Kiyoshi; Inada, Yutaka; Yagi, Nobuaki; Naito, Yuji; Otake, Yosuke; Nakajima, Takeshi; Matsuda, Takahisa; Yanagisawa, Akio; Itoh, Yoshito

    2014-01-01

    This study aimed to analyze the endoscopic mucosal resection (EMR) with a novel uniquely shaped, double-loop snare (Dualoop, Medico's Hirata Inc., Tokyo, Japan) for colorectal polyps. This was a clinical trial conducted in two referral centers, Kyoto Prefectural University of Medicine and National Cancer Center Hospital in Japan. First, the firmness of various snares including 'Dualoop' was experimentally analyzed with a pressure gauge. Five hundred and eighty nine consecutive polyps that underwent EMR with 'Dualoop' were compared to 339 polyps with the standard round snare. Lesion characteristics, en bloc resection, and complications were analyzed. 'Dualoop' had the most firmness among the various snares. The average tumor size was 9.3 mm (5-30), and en bloc resection was achieved in 95.4%. The rate of en bloc resection for middle polyps 15-19 mm in diameter was significantly higher with the 'Dualoop' than that with the round snare (97.9 vs. 80.0%, p < 0.05). The rate of en bloc resection was 64.7% for large polyps ≥20 mm in diameter using 'Dualoop'. Higher age, larger tumor size, and superficial polyps were associated with the failure of en bloc resection. EMR with 'Dualoop' was effective for resecting both middle and large polyps en-bloc. © 2014 S. Karger AG, Basel.

  18. NDE: A key to engine rotor life prediction

    NASA Technical Reports Server (NTRS)

    Doherty, J. E.

    1977-01-01

    A key ingredient in the establishment of safe life times for critical components is the means of reliably detecting flaws which may potentially exist. Currently used nondestructive evaluation procedures are successful in detecting life limiting defects; however, the development of automated and computer aided NDE technology permits even greater assurance of flight safety.

  19. Potential clinical impact of advanced imaging and computer-aided diagnosis in chest radiology: importance of radiologist's role and successful observer study.

    PubMed

    Li, Feng

    2015-07-01

    This review paper is based on our research experience in the past 30 years. The importance of radiologists' role is discussed in the development or evaluation of new medical images and of computer-aided detection (CAD) schemes in chest radiology. The four main topics include (1) introducing what diseases can be included in a research database for different imaging techniques or CAD systems and what imaging database can be built by radiologists, (2) understanding how radiologists' subjective judgment can be combined with technical objective features to improve CAD performance, (3) sharing our experience in the design of successful observer performance studies, and (4) finally, discussing whether the new images and CAD systems can improve radiologists' diagnostic ability in chest radiology. In conclusion, advanced imaging techniques and detection/classification of CAD systems have a potential clinical impact on improvement of radiologists' diagnostic ability, for both the detection and the differential diagnosis of various lung diseases, in chest radiology.

  20. Automatic bone detection and soft tissue aware ultrasound-CT registration for computer-aided orthopedic surgery.

    PubMed

    Wein, Wolfgang; Karamalis, Athanasios; Baumgartner, Adrian; Navab, Nassir

    2015-06-01

    The transfer of preoperative CT data into the tracking system coordinates within an operating room is of high interest for computer-aided orthopedic surgery. In this work, we introduce a solution for intra-operative ultrasound-CT registration of bones. We have developed methods for fully automatic real-time bone detection in ultrasound images and global automatic registration to CT. The bone detection algorithm uses a novel bone-specific feature descriptor and was thoroughly evaluated on both in-vivo and ex-vivo data. A global optimization strategy aligns the bone surface, followed by a soft tissue aware intensity-based registration to provide higher local registration accuracy. We evaluated the system on femur, tibia and fibula anatomy in a cadaver study with human legs, where magnetically tracked bone markers were implanted to yield ground truth information. An overall median system error of 3.7 mm was achieved on 11 datasets. Global and fully automatic registration of bones aquired with ultrasound to CT is feasible, with bone detection and tracking operating in real time for immediate feedback to the surgeon.

  1. Computer-aided diagnosis workstation and database system for chest diagnosis based on multi-helical CT images

    NASA Astrophysics Data System (ADS)

    Satoh, Hitoshi; Niki, Noboru; Mori, Kiyoshi; Eguchi, Kenji; Kaneko, Masahiro; Kakinuma, Ryutarou; Moriyama, Noriyuki; Ohmatsu, Hironobu; Masuda, Hideo; Machida, Suguru; Sasagawa, Michizou

    2006-03-01

    Multi-helical CT scanner advanced remarkably at the speed at which the chest CT images were acquired for mass screening. Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. To overcome this problem, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images and a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification. We also have developed electronic medical recording system and prototype internet system for the community health in two or more regions by using the Virtual Private Network router and Biometric fingerprint authentication system and Biometric face authentication system for safety of medical information. Based on these diagnostic assistance methods, we have now developed a new computer-aided workstation and database that can display suspected lesions three-dimensionally in a short time. This paper describes basic studies that have been conducted to evaluate this new system. The results of this study indicate that our computer-aided diagnosis workstation and network system can increase diagnostic speed, diagnostic accuracy and safety of medical information.

  2. Risk of Metachronous High-Risk Adenomas and Large Serrated Polyps in Individuals With Serrated Polyps on Index Colonoscopy: Data From the New Hampshire Colonoscopy Registry.

    PubMed

    Anderson, Joseph C; Butterly, Lynn F; Robinson, Christina M; Weiss, Julia E; Amos, Christopher; Srivastava, Amitabh

    2018-01-01

    Surveillance guidelines for serrated polyps (SPs) are based on limited data on longitudinal outcomes of patients. We used the New Hampshire Colonoscopy Registry to evaluate risk of clinically important metachronous lesions associated with SPs detected during index colonoscopies. We collected data from a population-based colonoscopy registry that has been collecting and analyzing data on colonoscopies across the state of New Hampshire since 2004, including rates of adenoma and SP detection. Patients completed a questionnaire to determine demographic characteristics, health history, and risk factors for colorectal cancer, and were followed from index colonoscopy through all subsequent surveillance colonoscopies. Our analyses included 5433 participants (median age, 61 years; 49.7% male) with 2 colonoscopies (median time to surveillance, 4.9 years). We used multivariable logistic regression models to assess effects of index SPs (n = 1016), high-risk adenomas (HRA, n = 817), low-risk adenomas (n = 1418), and no adenomas (n = 3198) on subsequent HRA or large SPs (>1 cm) on surveillance colonoscopy (metachronous lesions). Synchronous SPs, within each index risk group, were assessed for size and by histology. SPs comprise hyperplastic polyps, sessile serrated adenomas/polyps (SSA/Ps), and traditional serrated adenomas. In this study, SSA/Ps and traditional serrated adenomas are referred to collectively as STSAs. HRA and synchronous large SP (odds ratio [OR], 5.61; 95% confidence interval [CI], 1.72-18.28), HRA with synchronous STSA (OR, 16.04; 95% CI, 6.95-37.00), and HRA alone (OR, 3.86; 95% CI, 2.77-5.39) at index colonoscopy significantly increased the risk of metachronous HRA compared to the reference group (no index adenomas or SPs). Large index SPs alone (OR, 14.34; 95% CI, 5.03-40.86) or index STSA alone (OR, 9.70; 95% CI, 3.63-25.92) significantly increased the risk of a large metachronous SP. In an analysis of data from a population-based colonoscopy registry, we found index large SP or index STSA with no index HRA increased risk of metachronous large SPs but not metachronous HRA. HRA and synchronous SPs at index colonoscopy significantly increased risk of metachronous HRA. Individuals with HRA and synchronous large SP or any STSA could therefore benefit from close surveillance. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

  3. Adaptive deformable model for colonic polyp segmentation and measurement on CT colonography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yao Jianhua; Summers, Ronald M.

    2007-05-15

    Polyp size is one important biomarker for the malignancy risk of a polyp. This paper presents an improved approach for colonic polyp segmentation and measurement on CT colonography images. The method is based on a combination of knowledge-guided intensity adjustment, fuzzy clustering, and adaptive deformable model. Since polyps on haustral folds are the most difficult to be segmented, we propose a dual-distance algorithm to first identify voxels on the folds, and then introduce a counter-force to control the model evolution. We derive linear and volumetric measurements from the segmentation. The experiment was conducted on 395 patients with 83 polyps, ofmore » which 43 polyps were on haustral folds. The results were validated against manual measurement from the optical colonoscopy and the CT colonography. The paired t-test showed no significant difference, and the R{sup 2} correlation was 0.61 for the linear measurement and 0.98 for the volumetric measurement. The mean Dice coefficient for volume overlap between automatic and manual segmentation was 0.752 (standard deviation 0.154)« less

  4. Localization of Short-Chain Polyphosphate Enhances its Ability to Clot Flowing Blood Plasma

    NASA Astrophysics Data System (ADS)

    Yeon, Ju Hun; Mazinani, Nima; Schlappi, Travis S.; Chan, Karen Y. T.; Baylis, James R.; Smith, Stephanie A.; Donovan, Alexander J.; Kudela, Damien; Stucky, Galen D.; Liu, Ying; Morrissey, James H.; Kastrup, Christian J.

    2017-02-01

    Short-chain polyphosphate (polyP) is released from platelets upon platelet activation, but it is not clear if it contributes to thrombosis. PolyP has increased propensity to clot blood with increased polymer length and when localized onto particles, but it is unknown whether spatial localization of short-chain polyP can accelerate clotting of flowing blood. Here, numerical simulations predicted the effect of localization of polyP on clotting under flow, and this was tested in vitro using microfluidics. Synthetic polyP was more effective at triggering clotting of flowing blood plasma when localized on a surface than when solubilized in solution or when localized as nanoparticles, accelerating clotting at 10-200 fold lower concentrations, particularly at low to sub-physiological shear rates typical of where thrombosis occurs in large veins or valves. Thus, sub-micromolar concentrations of short-chain polyP can accelerate clotting of flowing blood plasma under flow at low to sub-physiological shear rates. However, a physiological mechanism for the localization of polyP to platelet or vascular surfaces remains unknown.

  5. Serrated pathway in colorectal carcinogenesis

    PubMed Central

    Yamane, Letícia; Scapulatempo-Neto, Cristovam; Reis, Rui Manuel; Guimarães, Denise Peixoto

    2014-01-01

    Serrated adenocarcinoma is a recently described subset of colorectal cancer (CRC), which account for about 10% of all CRCs and follows an alternative pathway in which serrated polyps replace the traditional adenoma as the precursor lesion to CRC. Serrated polyps form a heterogeneous group of colorectal lesions that includes hyperplastic polyps (HPs), sessile serrated adenoma (SSA), traditional serrated adenoma (TSA) and mixed polyps. HPs are the most common serrated polyp followed by SSA and TSA. This distinct histogenesis is believed to have a major influence in prevention strategies, patient prognosis and therapeutic impact. Genetically, serrated polyps exhibited also a distinct pattern, with KRAS and BRAF having an important contribution to its development. Two other molecular changes that have been implicated in the serrated pathway include microsatellite instability and the CpG island methylator phenotype. In the present review we will address the current knowledge of serrated polyps, clinical pathological features and will update the most recent findings of its molecular pathways. The understanding of their biology and malignancy potential is imperative to implement a surveillance approach in order to prevent colorectal cancer development. PMID:24627599

  6. Inflammatory myoglandular colorectal polyps: a series of seven cases and review of literature.

    PubMed

    Becheanu, G; Gheorghe, C; Dumbravă, M; Serban-Barbu, V; Diculescu, M

    2011-01-01

    Inflammatory myoglandular polyp is an unusual but distinct, non-neoplastic type of colorectal polyp, commonly with a distal localization at the recto-sigmoidian level. It was first described in 1992 by Nakamura and his colleagues and it is considered to have few particular histological features. We report a series of seven cases (two male and five female patients) of myoglandular polyps with different localization from 15 to 40 cm from anus. Only four out of seven cases presented with rectal bleeding, the others polyps we incidentally discovered. The polyps varied between 4 and 30 mm in the maximum diameter. Grossly, they had firm consistency and smooth reddish surface. Histological examination of the specimens revealed hyperplastic glands with occasional cystic dilatation, proliferation of smooth muscle with no regular distribution, a variable amount of granulation tissue (usually minimal) and no evidence of epithelial dysplasia. All the lesions were removed endoscopically without any complications. Inflammatory myoglandular polyps are distinct histopathological entities, with insufficiently investigated pathogenesis that can include local trauma, mucosal prolapse or ischemia. Being benign they can be removed endoscopically, surgical treatment being reserved in selected cases.

  7. [Application of metal hemoclip for endoscopic polypectomy in children with thick-pedunculated intestinal polyps].

    PubMed

    Deng, Zhao-hui; Xu, Chun-di; Zhong, Jie; Chen, Shun-nian; Yao, Wei-jiong

    2004-03-01

    With the development of endoscopic therapy in children, endoscopic electrocoagulation polypectomy had gradually replaced surgery and became an important method to resect gastrointestinal polyps in children. Simple electrocoagulation polypectomy could often bring some complications of gastrointestinal bleeding and perforation because of incomplete electrocoagulation or mechanical incision, especially in gastrointestinal thick-pedunculated polyps which always have thick nutrient blood vessel. Hemoclips can successfully interdict arteriovenous blood because it can clamp tissue firmly without causing necrosis around the target area. Based on its good mechanical hemostasis, hemoclips are not only widely used in treating bleeding like from ulcer, tumor and variceal ligation but also used in removal of thick-pedunculated gastrointestinal polyps in adults. This paper describes the application of endoscopic electrocoagulation with metal hemoclips to remove thick-pedunculated intestinal polpys in children for the first time, sums up the experience and evaluates its efficacy and safety. Between October, 2001 and December, 2002, 5 cases with thick-pedunculated intestinal polpys were presented. The age of the patients ranged from 3 to 5 years. The clinical features were gastrointestinal bleeding or abdominal pain. The longest course of disease was 2 years. Enough preparations for alimentary tract were necessary for polypectomy. The procedures were performed under general anesthesia in order to avoid the risk of bleeding aspiration. Endoscopy was performed in the standard fashion. The apparatus included electronic colonic endoscope (XQ 200, Fuji Corp, Tokyo, Japan), snare (XQ200, Fuji Corp, Tokyo, Japan), impeller of the clip (HX-5QR-1) and hemoclip (MD850) which could be passed through the biopsy channel of endoscope. The clip was completely covered with a hood avoiding any injury to the mucous membrane. The pedicel with diameter of more than 1.0 cm underwent endoscopic electrocoagulation polypectomy with hemoclips. The clip contacted polyps in upright direction. One or more hemoclips were selected to clamp the proximal basement of the pedicel in terms of the pedicel diameter. Turning of the red colour of polyps to purple suggested that hemoclip interdicted arteriovenous blood effectively. The clip was then shut off and electrocoagulation polypectomy was followed. Six polyps were observed and removed. Six polyps including 2 transverse colon polyps and 4 descending colon polyps were resected. Pathological results showed that 3 were juvenile polyps and the other 3 adenomatous polyps. All the polyps were completely resected. The diameter of pedicel were 1.2 - 2.2 cm. The head and pedicel of the biggest polyp was about 5 cm x 5 cm and 2.2 cm, respectively, and five clips were used in order to remove it. No complications of bleeding and perforation were observed in these children. All hemoclips were expelled from intestines within one week. The symptoms of these patients disappeared. Mechanical hemostasis with hemoclips successfully interdicted arteriovenous blood of thick-pedunculated polyps. Hemoclips can successfully prevent the complications of bleeding and perforation. The clipping brings about a new method in endoscopic therapy. Endoscopic electrocoagulation polypectomy with hemoclips is a simple, safe and effective method to treat thick-pedunculated gastrointestinal polyps in children and it is a valuable tool in polypectomy for children.

  8. Predictive values of FAP and HGF for tumor angiogenesis and metastasis in colorectal cancer.

    PubMed

    Ma, T H; Gao, C C; Xie, R; Yang, X Z; Dai, W J; Zhang, J L; Yan, W; Wu, S N

    2017-01-01

    This study aims to explore the correlation of hepatocyte growth factor (HGF) and fibroblast activation protein (FAP) expressions with the angiogenesis and metastasis in colorectal cancer (CRC). The immunohistochemical SABC method was used to detect HGF and FAP expressions in 127 CRC tissues, 51 colorectal polyp tissues and 28 normal tissues. HGF and FAP expressions in liver metastasis were detected using western blot to analyze the correlation of their expressions with lymph node metastasis and liver metastasis. Micro-vessel density (MVD) and clinic-pathologic information of CRC patients were recorded and analyzed. In CRC group, HGF and FAP expressions were greatly higher than those in normal group and colorectal polyps group (P < 0.05). Moreover, the positive rates of HGF and FAP expressions in lymph node metastasis were evidently higher than those in non-lymph node metastasis (P < 0.05). In liver metastasis group, HGF and FAP expressions were obviously higher than non-liver metastasis group (P < 0.05). CRC group had much more MVD in comparison with normal group and colorectal polyps group (P < 0.05).When compared with negative group, MVD was significantly higher than that in CRC tissue with positive HGF and FAP (P < 0.05). Spearman rank correlation analysis showed that HGF and FAP were in positive correlation with MVD (r = 0.542, P < 0.001; r = 0.753, P < 0.001). These results indicate that FAP and HGF play an important role in CRC angiogenesis, and their expression levels are valuable to predict CRC liver metastasis and lymph node metastasis.

  9. Congenital hypertrophy of retinal pigment epithelium (CHRPE) in patients with familial adenomatous polyposis (FAP); a polyposis registry experience.

    PubMed

    Nusliha, Anwer; Dalpatadu, Ushantha; Amarasinghe, Binara; Chandrasinghe, Pramodh Chitral; Deen, Kemal Ismail

    2014-10-18

    Familial Adenomatous Polyposis (FAP) is an autosomal dominant condition giving rise to multiple adenomatous polyps in the colon which invariably become malignant by the fourth decade. Congenital hypertrophy of retinal pigment epithelium (CHRPE) is one of its extra intestinal manifestations early in childhood seen, present in 90% of FAP population and is easy to detect. Patients diagnosed with FAP and at risk first degree family members were screened for CHRPE using a slit lamp and indirect ophthalmoscopy. The retina of 17 diagnosed FAP patients and 13 individuals at risk were examined. The site and size of CHRPE lesions were documented. Thirteen (76%) of 17 FAP patients (male-10, female - 7, median age - 30 years; range 15-55 years) had CHRPE lesions; seven (54%) had bilateral CHRPE lesions and six (46%) had unilateral lesions. A single lesion was detected in 6 (46%) while 7 (54%) patients had multiple lesions. Of 13 at risk individuals (7- male, female-6 ; median age 34; range 16-52 years), one was positive for CHRPE and 12 were free of retinal lesions. The sensitivity of the presence of a CHRPE lesion in association with colonic polyps in FAP was 76%, specificity 92%, positive predictive value 93%, and negative predictive value 75%. This study found a high sensitivity and specificity for a CHRPE lesion to be associated with colonic polyps of FAP and hence a useful screening method in a burdened health-care system. The method is minimally invasive and simple and would be of particular value in screening children at risk for FAP.

  10. Computer-aided diagnosis workstation and telemedicine network system for chest diagnosis based on multislice CT images

    NASA Astrophysics Data System (ADS)

    Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Ohmatsu, Hironobu; Kakinuma, Ryutaru; Moriyama, Noriyuki

    2009-02-01

    Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. Moreover, the doctor who diagnoses a medical image is insufficient in Japan. To overcome these problems, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images, a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification and a vertebra body analysis algorithm for quantitative evaluation of osteoporosis likelihood by using helical CT scanner for the lung cancer mass screening. The functions to observe suspicious shadow in detail are provided in computer-aided diagnosis workstation with these screening algorithms. We also have developed the telemedicine network by using Web medical image conference system with the security improvement of images transmission, Biometric fingerprint authentication system and Biometric face authentication system. Biometric face authentication used on site of telemedicine makes "Encryption of file" and "Success in login" effective. As a result, patients' private information is protected. We can share the screen of Web medical image conference system from two or more web conference terminals at the same time. An opinion can be exchanged mutually by using a camera and a microphone that are connected with workstation. Based on these diagnostic assistance methods, we have developed a new computer-aided workstation and a new telemedicine network that can display suspected lesions three-dimensionally in a short time. The results of this study indicate that our radiological information system without film by using computer-aided diagnosis workstation and our telemedicine network system can increase diagnostic speed, diagnostic accuracy and security improvement of medical information.

  11. Recent development on computer aided tissue engineering--a review.

    PubMed

    Sun, Wei; Lal, Pallavi

    2002-02-01

    The utilization of computer-aided technologies in tissue engineering has evolved in the development of a new field of computer-aided tissue engineering (CATE). This article reviews recent development and application of enabling computer technology, imaging technology, computer-aided design and computer-aided manufacturing (CAD and CAM), and rapid prototyping (RP) technology in tissue engineering, particularly, in computer-aided tissue anatomical modeling, three-dimensional (3-D) anatomy visualization and 3-D reconstruction, CAD-based anatomical modeling, computer-aided tissue classification, computer-aided tissue implantation and prototype modeling assisted surgical planning and reconstruction.

  12. Spontaneous resolution of hemorrhagic polyps of the true vocal fold.

    PubMed

    Klein, Adam M; Lehmann, Marcus; Hapner, Edie R; Johns, Michael M

    2009-01-01

    Hemorrhagic polyps are the most common benign lesions surgically removed from the vocal folds. Although this modality does offer satisfactory results in most of the cases, there is a subset of polyps that seems to resolve with conservative therapy. This study was performed to examine this subset of polyps. Thirty-four consecutive subjects diagnosed with hemorrhagic polyps of the true vocal fold were retrospectively reviewed to determine the incidence of spontaneous resolution of the lesions with nonsurgical therapy. Sixteen subjects began conservative therapy, consisting of voice therapy and proper vocal hygiene, often while awaiting an optimal personal time for surgical intervention. Of these subjects, nine (56.3%) experienced a resolution of their lesion and symptoms without undergoing surgical therapy. Surgical removal of hemorrhagic polyps is often considered the standard of treatment for these benign lesions. However, these observations support a regimen of voice therapy and observation in select cases.

  13. [Gastric polyps. Experience at the department of endoscopy of the Salvador Zubirán National Institute of Nutrition].

    PubMed

    Santiago Gallo, R; Rodríguez Hernández, H; Elizondo Rivera, J

    1990-01-01

    During 1981-1989 we seen 54 patients with gastric polyps in the Instituto Nacional de la Nutrición SZ, Endoscopy Dept., México City. We found 100 polyps among 15,974 upper endoscopy studies (0.33%), being multiple in 22 patients with an overall of 68 polyps. Females had a predominance of 2:1 with prevalence from the 5th to 8th decades. All were asymptomatic in regard to polyps. Its main locations were in antrum (46%) and corpus (39%). They measured an average of 8 mm with a range from 5 to 25. Only three adenomatous polyps shows dysplastic changes, two with moderate dysplasia and one, bigger than 20 mm, had severe dysplasia (carcinoma in situ). Histological findings were: Inflammatory (chronic gastritis) 30%, adenomatous 22%, hyperplastic 17% and hamartomatous 13%. In seven patients we seen recurrence at follow up.

  14. A case of gastric hamartomatous inverted polyp resected endoscopically

    PubMed Central

    Dohi, Moyu; Gen, Yasuyuki; Yoshioka, Mika

    2016-01-01

    We report the case of a 55-year-old woman with a tumor in the greater curvature of the upper gastric body. The tumor was incidentally found on an upper gastrointestinal X-ray series performed during a routine medical examination. Whereas endoscopy revealed a gastric submucosal tumor (SMT), endoscopic ultrasonography demonstrated a heterogeneous tumor with small, cystic, hypoechoic spots originating from the second layer. The patient was clinically asymptomatic, with no contributory family history or abnormal laboratory data. The results of a physical examination, abdominal computed tomography, and plain chest radiography were all unremarkable. Although the endoscopic tumor type was determined to be SMT, the tumor was successfully resected by endoscopic submucosal dissection (ESD) and subsequently diagnosed as a gastric hamartomatous inverted polyp (GHIP). The findings of the present case highlight the importance of considering GHIP as a diagnosis and indicate the utility of en bloc resection of GHIP with ESD. PMID:27556064

  15. Lymphangioma of the jejunal mesentery and jejunal polyps presenting as an acute abdomen in a teenager.

    PubMed

    Jayasundara, Jasb; Perera, E; Chandu de Silva, M V; Pathirana, A A

    2017-03-01

    Cystic lymphangioma of the small bowel mesentery is a rare clinical entity, especially after childhood. Medical literature reveals a limited number of such cases presenting as acute abdomen due to bowel obstruction, small bowel volvulus and bleeding into the tumour. We present the management experience of an 18-year-old woman who presented with rapid onset diffuse peritonism and raised inflammatory markers. Computed tomography showed a mass in the small bowel mesentery with suspicion of segmental bowel ischaemia. Emergency laparotomy revealed a mass in the mid-jejunal mesentery close to the bowel wall with no bowel ischaemia. The patient made an uncomplicated recovery after segmental bowel resection and end-to-end anastomosis. Histology confirmed the mass as a cystic lymphangioma involving the jejunal mesentery and two small jejunal polyps. Lymphangioma could be considered in the differential diagnosis of an acute abdomen in a young adult when the presentation is atypical.

  16. The activity of N-acetyl-β-d-hexosaminidase A and B and β-glucuronidase in nasal polyps and hypertrophic nasal concha.

    PubMed

    Chojnowska, Sylwia; Minarowska, Alina; Waszkiewicz, Napoleon; Kępka, Alina; Zalewska-Szajda, Beata; Gościk, Elżbieta; Kowal, Krzysztof; Olszewska, Ewa; Konarzewska-Duchnowska, Emilia; Minarowski, Łukasz; Zwierz, Krzysztof; Ładny, Jerzy Robert; Szajda, Sławomir Dariusz

    2014-01-01

    Nasal polyps and hypertrophic lower nasal conchae are common disorders of nasal cavity. The majority of etiopathogenetic theories indicate inflammatory background of polyps and hypertrophic concha. N-acetyl-β-D-hexosaminidase and β-glucuronidase are lysosomal exoglycosidases revealing accelerated activity in inflammatory processes. The aim of the study was to evaluate the catabolism of glycoconjugates in nasal polyps and hypertrophic nasal concha basing on the activity of N-acetyl-β-D-hexosaminidase (HEX) and β-glucuronidase (GLU). Material consisted of nasal polyps taken from 40 patients during polypectomy in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and hypertrophic lower nasal conchae taken from 20 patients during mucotomy. The activity of HEX, HEX A, HEX B and GLU in supernatant of homogenates of nasal polyps and hypertrophic lower nasal concha tissues has been estimated using colorimetric method. Statistically significant decrease has been observed in concentration of the activity (per 1mg of tissue) of HEX (p<0.05), HEX B (p<0.001) and specific activity (per 1mg of protein) of HEX B (p<0.001) in nasal polyps tissue in comparison to hypertrophic lower nasal conchae tissue. Decrease in the activity and specific activity concentration of the majority of examined lysosomal exoglycosidases (increasing in inflammations) in comparison to hypertrophic lower nasal conchae suggests electrolytes disorders and questions the inflammatory background of nasal polyps. Copyright © 2013 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

  17. Conjugated linoleic acids differentially alter polyp number and diameter in the Apc(min/+) mouse model of intestinal cancer.

    PubMed

    Mandir, N; Goodlad, R A

    2008-04-01

    Dietary conjugated linoleic acids (CLA) have had many health benefits claimed for them, including antineoplastic actions. The effects of the predominant forms of CLA, namely the c9t11 and t10c12 isomers, or a mixture of these on polyp development, were investigated in the Apc(Min/+) mouse. CLAs have also been linked to altered rates of cell renewal and cell proliferation so this was also studied, as was a further means of increasing tissue mass, namely crypt fission. The stomach and small intestine were significantly heavier in the t10c12, and in the mixture-treated groups (P < 0.001). Crypt fission was increased in the middle small intestine by the t10c12 diet while colonic weight was reduced by c9t11 provision and crypts were 20% shorter. The t10c12 and the mixture significantly reduced polyp number in the proximal small intestine but they increased polyp diameter in the middle and distal small intestine, to an extent that the polyp burden was significantly increased at these sites. All CLAs significantly reduced polyp number in the colon, but the mixture significantly increased polyp diameter in the colon. Increased polyp diameter associated with t10c12 diet and especially with the mixture is a cause of concern, as this is the commercially available form. The naturally occurring isomer, c9t11 decreased colonic polyp number and did not increase diameter, suggesting that this natural isomer is the most likely to be protective.

  18. Location in the right hemi-colon is an independent risk factor for delayed post-polypectomy hemorrhage: a multi-center case-control study.

    PubMed

    Buddingh, K Tim; Herngreen, Thomas; Haringsma, Jelle; van der Zwet, Wil C; Vleggaar, Frank P; Breumelhof, Ronald; Ter Borg, Frank

    2011-06-01

    Delayed hemorrhage is an infrequent, but serious complication of colonoscopic polypectomy. Large size is the only polyp-related factor that has been unequivocally proven to increase the risk of delayed bleeding. It has been suggested that location in the right hemi-colon is also a risk factor. The objective of this study was to determine whether polyp location is an independent risk factor for delayed post-polypectomy hemorrhage. A retrospective case-control study was conducted in two university hospitals and two community hospitals. Thirty-nine cases and 117 controls were identified. In multivariate analysis, size and location were found to be independent polyp-related risk factors for delayed type hemorrhage. The risk increased by 13% for every 1 mm increase in polyp diameter (odds ratio (OR) 1.13, 95% confidence interval (CI) 1.05-1.20, P<0.001). Polyps located in the right hemi-colon had an OR of 4.67 (1.88-11.61, P=0.001) for delayed hemorrhage. Polyps in the cecum seemed to be especially at high risk in univariate analysis (OR 13.82, 95% CI 2.66-71.73), but this could not be assessed in multivariate analysis as the number of cases was too small. Polyp type (sessile or pedunculated) was not a risk factor. Polyp location in the right hemi-colon seems to be an independent and substantial risk factor for delayed post-polypectomy hemorrhage. A low threshold for preventive hemostatic measures is advised when removing polyps from this region.

  19. A Set of Image Processing Algorithms for Computer-Aided Diagnosis in Nuclear Medicine Whole Body Bone Scan Images

    NASA Astrophysics Data System (ADS)

    Huang, Jia-Yann; Kao, Pan-Fu; Chen, Yung-Sheng

    2007-06-01

    Adjustment of brightness and contrast in nuclear medicine whole body bone scan images may confuse nuclear medicine physicians when identifying small bone lesions as well as making the identification of subtle bone lesion changes in sequential studies difficult. In this study, we developed a computer-aided diagnosis system, based on the fuzzy sets histogram thresholding method and anatomical knowledge-based image segmentation method that was able to analyze and quantify raw image data and identify the possible location of a lesion. To locate anatomical reference points, the fuzzy sets histogram thresholding method was adopted as a first processing stage to suppress the soft tissue in the bone images. Anatomical knowledge-based image segmentation method was then applied to segment the skeletal frame into different regions of homogeneous bones. For the different segmented bone regions, the lesion thresholds were set at different cut-offs. To obtain lesion thresholds in different segmented regions, the ranges and standard deviations of the image's gray-level distribution were obtained from 100 normal patients' whole body bone images and then, another 62 patients' images were used for testing. The two groups of images were independent. The sensitivity and the mean number of false lesions detected were used as performance indices to evaluate the proposed system. The overall sensitivity of the system is 92.1% (222 of 241) and 7.58 false detections per patient scan image. With a high sensitivity and an acceptable false lesions detection rate, this computer-aided automatic lesion detection system is demonstrated as useful and will probably in the future be able to help nuclear medicine physicians to identify possible bone lesions.

  20. Cervical polyps

    MedlinePlus

    ... on the cervix during a pelvic exam. A cervical biopsy will be performed. Most of the time, the biopsy will show cells that are consistent with a benign polyp. Rarely, there may be abnormal, precancerous, or cancer cells in a polyp. Treatment The provider can ...

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