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Sample records for comparative diagnostic imaging

  1. Diagnostic Imaging

    MedlinePlus

    Diagnostic imaging lets doctors look inside your body for clues about a medical condition. A variety of machines and techniques can create pictures of the structures and activities inside your body. The type of imaging your doctor uses depends on your symptoms and ...

  2. Diagnostic agreement when comparing still and video imaging for the medical evaluation of child sexual abuse.

    PubMed

    Killough, Emily; Spector, Lisa; Moffatt, Mary; Wiebe, Jan; Nielsen-Parker, Monica; Anderst, Jim

    2016-02-01

    Still photo imaging is often used in medical evaluations of child sexual abuse (CSA) but video imaging may be superior. We aimed to compare still images to videos with respect to diagnostic agreement regarding hymenal deep notches and transections in post-pubertal females. Additionally, we evaluated the role of experience and expertise on agreement. We hypothesized that videos would result in improved diagnostic agreement of multiple evaluators as compared to still photos. This was a prospective quasi-experimental study using imaging modality as the quasi-independent variable. The dependent variable was diagnostic agreement of participants regarding presence/absence of findings indicating penetrative trauma on non-acute post-pubertal genital exams. Participants were medical personnel who regularly perform CSA exams. Diagnostic agreement was evaluated utilizing a retrospective selection of videos and still photos obtained directly from the videos. Videos and still photos were embedded into an on-line survey as sixteen cases. One-hundred sixteen participants completed the study. Participant diagnosis was more likely to agree with study center diagnosis when using video (p<0.01). Use of video resulted in statistically significant changes in diagnosis in four of eight cases. In two cases, the diagnosis of the majority of participants changed from no hymenal transection to transection present. No difference in agreement was found based on experience or expertise. Use of video vs. still images resulted in increased agreement with original examiner and changes in diagnostic impressions in review of CSA exams. Further study is warranted, as video imaging may have significant impacts on diagnosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Localization of Diagnostically Relevant Regions of Interest in Whole Slide Images: a Comparative Study.

    PubMed

    Mercan, Ezgi; Aksoy, Selim; Shapiro, Linda G; Weaver, Donald L; Brunyé, Tad T; Elmore, Joann G

    2016-08-01

    Whole slide digital imaging technology enables researchers to study pathologists' interpretive behavior as they view digital slides and gain new understanding of the diagnostic medical decision-making process. In this study, we propose a simple yet important analysis to extract diagnostically relevant regions of interest (ROIs) from tracking records using only pathologists' actions as they viewed biopsy specimens in the whole slide digital imaging format (zooming, panning, and fixating). We use these extracted regions in a visual bag-of-words model based on color and texture features to predict diagnostically relevant ROIs on whole slide images. Using a logistic regression classifier in a cross-validation setting on 240 digital breast biopsy slides and viewport tracking logs of three expert pathologists, we produce probability maps that show 74 % overlap with the actual regions at which pathologists looked. We compare different bag-of-words models by changing dictionary size, visual word definition (patches vs. superpixels), and training data (automatically extracted ROIs vs. manually marked ROIs). This study is a first step in understanding the scanning behaviors of pathologists and the underlying reasons for diagnostic errors.

  4. Chronic pelvic pain: how does noninvasive imaging compare with diagnostic laparoscopy?

    PubMed

    Tirlapur, Seema A; Daniels, Jane P; Khan, Khalid S

    2015-12-01

    Chronic pelvic pain (CPP) has an annual prevalence of 38/1000 in the UK, with coexisting pathologies often present. Diagnostic laparoscopy has long been the gold standard diagnostic test, but with up to 40% showing no abnormality, we explore the value of noninvasive imaging, such as pelvic ultrasound and MRI. A literature review from inception until January 2015 of the following databases: PubMed, MEDLINE, Cumulative Index to Nursing and Allied Health Literature, Excerpta Medica database, and System for Information on Grey Literature in Europe were performed to identify published studies assessing the usefulness of ultrasound, MRI, and laparoscopy in the diagnosis of CPP. Three studies (194 women) addressed their comparative performance in patients with endometriosis, showing the sensitivity of ultrasound ranged between 58 and 88.5%; MRI was 56-91.5% and in the one study using histology as its reference standard, the sensitivity of laparoscopy was 85.7%. Noninvasive imaging has the additional benefit of being well tolerated, safer, and cheaper than surgery. CPP, by nature of its multifactorial causation, can be difficult to manage and often requires a multidisciplinary team. Ultrasound and MRI may provide information about the presence or lack of abnormality, which would allow general practitioners or office gynaecologists to initiate treatment and think about surgery as a second-line investigative tool.

  5. The quest for 'diagnostically lossless' medical image compression: a comparative study of objective quality metrics for compressed medical images

    NASA Astrophysics Data System (ADS)

    Kowalik-Urbaniak, Ilona; Brunet, Dominique; Wang, Jiheng; Koff, David; Smolarski-Koff, Nadine; Vrscay, Edward R.; Wallace, Bill; Wang, Zhou

    2014-03-01

    Our study, involving a collaboration with radiologists (DK,NSK) as well as a leading international developer of medical imaging software (AGFA), is primarily concerned with improved methods of assessing the diagnostic quality of compressed medical images and the investigation of compression artifacts resulting from JPEG and JPEG2000. In this work, we compare the performances of the Structural Similarity quality measure (SSIM), MSE/PSNR, compression ratio CR and JPEG quality factor Q, based on experimental data collected in two experiments involving radiologists. An ROC and Kolmogorov-Smirnov analysis indicates that compression ratio is not always a good indicator of visual quality. Moreover, SSIM demonstrates the best performance, i.e., it provides the closest match to the radiologists' assessments. We also show that a weighted Youden index1 and curve tting method can provide SSIM and MSE thresholds for acceptable compression ratios.

  6. Manual of diagnostic imaging

    SciTech Connect

    Gaylord, G.; Baker, S.; Davis, L.

    1988-01-01

    This book is on ordering and understanding the results of radiologic studies. Main sections are (I) Diagnostic Radiology serves as a basic introduction; (II) Diagnostic Modalities dedicates a chapter to each imaging modality in a clinical context, with a brief technical description and patient preparation guidelines; and (III) Organ System Imaging contains a chapter on each major organ system, covering the abilities and limitations of each modality to image a specific organ system and the significance of anatomic, physiologic, and general pathologic information.

  7. Distribution of breath sound images in patients with pneumothoraces compared to healthy subjects. Diagnostic yield of vibration response imaging technology.

    PubMed

    Blanco, Montserrat; Mor, Ram; Fraticelli, Anne; Breen, David P; Dutau, Hervé

    2009-01-01

    Vibration response imaging (VRI) is a new technology that provides a radiation-free dynamic lung image from the vibrations produced by airflow. The vibration energy from the respiratory cycle can be quantified for any lung region. This is obtained by integrating the energy profiles from 42 acoustic sensors placed on the patient's back. The aim of this study was to evaluate whether a physician trained in interpreting acoustic images can accurately distinguish between normal and abnormal breath sound distribution in patients with pneumothoraces compared to healthy controls. In total, 14 patients with spontaneous or iatrogenic pneumothoraces and 15 healthy volunteers were enrolled in the study. VRI recordings and physical examination were obtained in all cases. Chest radiographs (CXRs) were reviewed in patients with pneumothoraces. Dynamic images recorded during one complete respiratory cycle were analyzed for each subject. The VRI images of patients with pneumothoraces demonstrated a reduction in the vibration response on the affected side which correlated with the CXR. Sensitivity was 100%, specificity was 87% and positive predictive value and negative predictive value were 86 and 100%, respectively. This study demonstrates that VRI can be safely used to assess patients with pneumothoraces. Moreover, the analysis of breath sound distribution images obtained noninvasively can distinguish between patients with a normal chest examination from those with pneumothoraces. 2008 S. Karger AG, Basel.

  8. Diagnostic accuracy of an artificial neural network compared with statistical quantitation of myocardial perfusion images: a Japanese multicenter study.

    PubMed

    Nakajima, Kenichi; Kudo, Takashi; Nakata, Tomoaki; Kiso, Keisuke; Kasai, Tokuo; Taniguchi, Yasuyo; Matsuo, Shinro; Momose, Mitsuru; Nakagawa, Masayasu; Sarai, Masayoshi; Hida, Satoshi; Tanaka, Hirokazu; Yokoyama, Kunihiko; Okuda, Koichi; Edenbrandt, Lars

    2017-09-26

    Artificial neural networks (ANN) might help to diagnose coronary artery disease. This study aimed to determine whether the diagnostic accuracy of an ANN-based diagnostic system and conventional quantitation are comparable. The ANN was trained to classify potentially abnormal areas as true or false based on the nuclear cardiology expert interpretation of 1001 gated stress/rest (99m)Tc-MIBI images at 12 hospitals. The diagnostic accuracy of the ANN was compared with 364 expert interpretations that served as the gold standard of abnormality for the validation study. Conventional summed stress/rest/difference scores (SSS/SRS/SDS) were calculated and compared with receiver operating characteristics (ROC) analysis. The ANN generated a better area under the ROC curves (AUC) than SSS (0.92 vs. 0.82, p < 0.0001), indicating better identification of stress defects. The ANN also generated a better AUC than SDS (0.90 vs. 0.75, p < 0.0001) for stress-induced ischemia. The AUC for patients with old myocardial infarction based on rest defects was 0.97 (0.91 for SRS, p = 0.0061), and that for patients with and without a history of revascularization based on stress defects was 0.94 and 0.90 (p = 0.0055 and p < 0.0001 vs. SSS, respectively). The SSS/SRS/SDS steeply increased when ANN values (probability of abnormality) were >0.80. The ANN was diagnostically accurate in various clinical settings, including that of patients with previous myocardial infarction and coronary revascularization. The ANN could help to diagnose coronary artery disease.

  9. Diagnostic paediatric imaging

    SciTech Connect

    Hall, C.M.; Lingam, S.

    1986-01-01

    This book is a case study teaching manual presenting radiographs and examples of other imaging modalities from 100 paediatric patients. The material comes from the radiological teaching collection at the Hospital for Sick Children at Great Ormond Street in London and was compiled over a ten year period. With each case a short clinical history is given and a series of questions posed, similar to those encountered in postgraduate medical examinations. Sample answers with comments and more illustrations are presented on the following page. The last decade has seen a rapid expansion in the range and sophistication of diagnostic imaging modalities which are available to clinicians. Since it is impossible to achieve comprehensive coverage in a book of this size, the authors have selected examples of cases which illustrate the range of imaging modalities currently available and which may be encountered in both clinical practice and in examinations.

  10. [Diagnostic imaging of lying].

    PubMed

    Lass, Piotr; Sławek, Jarosław; Sitek, Emilia; Szurowska, Edyta; Zimmermann, Agnieszka

    2013-01-01

    Functional diagnostic imaging has been applied in neuropsychology for more than two decades. Nowadays, the functional magnetic resonance (fMRI) seems to be the most important technique. Brain imaging in lying has been performed and discussed since 2001. There are postulates to use fMRI for forensic purposes, as well as commercially, e.g. testing the loyalty of employees, especially because of the limitations of traditional polygraph in some cases. In USA fMRI is performed in truthfulness/lying assessment by at least two commercial companies. Those applications are a matter of heated debate of practitioners, lawyers and specialists of ethics. The opponents of fMRI use for forensic purposes indicate the lack of common agreement on it and the lack of wide recognition and insufficient standardisation. Therefore it cannot serve as a forensic proof, yet. However, considering the development of MRI and a high failure rate of traditional polygraphy, forensic applications of MRI seem to be highly probable in future.

  11. Diagnostic imaging in pediatric emergencies

    SciTech Connect

    Heller, R.M.; Coulam, C.M.; Allen, J.H.; Fleischer, A.; Lee, G.S.; Kirchner, S.G.; James A.E. Jr.

    1980-07-01

    Evaluation of pediatric emergencies by diagnostic imaging technics can involve both invasive and noninvasive procedures. Nuclear medicine, conventional radiography, ultrasound, computerized axial tomography, and xeroradiography are the major nonangiographic diagnostic technics available for patient evaluation. We will emphasize the use of computerized axial tomography, nuclear medicine, xeroradiography, and ultrasound in the evaluation of emergencies in the pediatric age group. Since the radiologist is the primary consultant with regard to diagnostic imaging, his knowledge of these modulities can greatly influence patient care and clinical results.

  12. Diagnostic imaging of osteosarcoma

    SciTech Connect

    Seeger, L.L.; Gold, R.H.; Chandnani, V.P. )

    1991-09-01

    The diagnosis, treatment planning, and follow-up evaluation of osteosarcoma rely heavily on a variety of imaging techniques. Plain roentgenography, radionuclide bone scanning, computed tomography, and magnetic resonance imaging play important roles in defining local tumor extent, detecting metastatic disease, and monitoring for recurrent tumor. Invasive studies such as angiography are now rarely necessary. In the future, newer imaging modalities, including positron emission tomography, can be expected to become important tools for evaluation of these tumors. 23 references.

  13. Patient Characteristics as Predictors of Image Quality and Diagnostic Accuracy of MDCT Compared With Conventional Coronary Angiography for Detecting Coronary Artery Stenoses: CORE-64 Multicenter International Trial

    PubMed Central

    Dewey, Marc; Vavere, Andrea L.; Arbab-Zadeh, Armin; Miller, Julie M.; Sara, Leonardo; Cox, Christopher; Gottlieb, Ilan; Yoshioka, Kunihiro; Paul, Narinder; Hoe, John; de Roos, Albert; Lardo, Albert C.; Lima, Joao A.; Clouse, Melvin E.

    2012-01-01

    OBJECTIVE The purpose of the study was to investigate patient characteristics associated with image quality and their impact on the diagnostic accuracy of MDCT for the detection of coronary artery stenosis. MATERIALS AND METHODS Two hundred ninety-one patients with a coronary artery calcification (CAC) score of ≤ 600 Agatston units (214 men and 77 women; mean age, 59.3 ± 10.0 years [SD]) were analyzed. An overall image quality score was derived using an ordinal scale. The accuracy of quantitative MDCT to detect significant (≥ 50%) stenoses was assessed using quantitative coronary angiography (QCA) per patient and per vessel using a modified 19-segment model. The effect of CAC, obesity, heart rate, and heart rate variability on image quality and accuracy were evaluated by multiple logistic regression. Image quality and accuracy were further analyzed in subgroups of significant predictor variables. Diagnostic analysis was determined for image quality strata using receiver operating characteristic (ROC) curves. RESULTS Increasing body mass index (BMI) (odds ratio [OR] = 0.89, p < 0.001), increasing heart rate (OR = 0.90, p < 0.001), and the presence of breathing artifact (OR = 4.97, p ≤ 0.001) were associated with poorer image quality whereas sex, CAC score, and heart rate variability were not. Compared with examinations of white patients, studies of black patients had significantly poorer image quality (OR = 0.58, p = 0.04). At a vessel level, CAC score (10 Agatston units) (OR = 1.03, p = 0.012) and patient age (OR = 1.02, p = 0.04) were significantly associated with the diagnostic accuracy of quantitative MDCT compared with QCA. A trend was observed in differences in the areas under the ROC curves across image quality strata at the vessel level (p = 0.08). CONCLUSION Image quality is significantly associated with patient ethnicity, BMI, mean scan heart rate, and the presence of breathing artifact but not with CAC score at a patient level. At a vessel level

  14. Diagnostic imaging of infertility

    SciTech Connect

    Winfield, A.C.; Wentz, A.C.

    1987-01-01

    This text presents a review of all the imaging modalities available in the diagnosis of infertility. This book integrates the perspectives of experts in ob/gyn, radiology, reproductive endocrinology, and urology. It's a one-of-a-kind ''how to'' guide to hysterosalpinography and infertility evaluation, providing complete clinical information on the techniques, pitfalls, problems encountered and differential diagnosis. Detailed descriptions accompany numerous high-quality illustrations to help correlate findings and give meaning to the radiographic and ultrasound images.

  15. Diagnostic imaging of child abuse.

    PubMed

    2009-05-01

    The role of imaging in cases of child abuse is to identify the extent of physical injury when abuse is present and to elucidate all imaging findings that point to alternative diagnoses. Effective diagnostic imaging of child abuse rests on high-quality technology as well as a full appreciation of the clinical and pathologic alterations occurring in abused children. This statement is a revision of the previous policy published in 2000.

  16. The ear: Diagnostic imaging

    SciTech Connect

    Vignaud, J.; Jardin, C.; Rosen, L.

    1986-01-01

    This is an English translation of volume 17-1 of Traite de radiodiagnostic and represents a reasonably complete documentation of the diseases of the temporal bone that have imaging manifestations. The book begins with chapters on embryology, anatomy and radiography anatomy; it continues with blood supply and an overview of temporal bone pathology. Subsequent chapters cover malformations, trauma, infections, tumors, postoperative changes, glomus tumors, vertebasilar insufficiency, and facial nerve canal lesions. A final chapter demonstrates and discusses magnetic resonance images of the ear and cerebellopontine angle.

  17. Introduction to diagnostic imaging

    SciTech Connect

    Sider, L.

    1986-01-01

    This book begins with a chapter that includes the history of the various imaging modalities currently available, including magnetic resonance imaging. The following six chapters review specific anatomic regions (chest, urinary tract, gastrointestinal tract, bones and joints, cardiovascular system, and central nervous system) and the abnormalities that can be detected by various radiologic studies of these areas. Each chapter focuses on a specific body system and gives a short description of what studies are typically used for each. The normal anatomy, as shown in these studies, is also discussed. A series of short sections on specific, common disease conditions of each area follows.

  18. Image Processing Diagnostics: Emphysema

    NASA Astrophysics Data System (ADS)

    McKenzie, Alex

    2009-10-01

    Currently the computerized tomography (CT) scan can detect emphysema sooner than traditional x-rays, but other tests are required to measure more accurately the amount of affected lung. CT scan images show clearly if a patient has emphysema, but is unable by visual scan alone, to quantify the degree of the disease, as it appears merely as subtle, barely distinct, dark spots on the lung. Our goal is to create a software plug-in to interface with existing open source medical imaging software, to automate the process of accurately diagnosing and determining emphysema severity levels in patients. This will be accomplished by performing a number of statistical calculations using data taken from CT scan images of several patients representing a wide range of severity of the disease. These analyses include an examination of the deviation from a normal distribution curve to determine skewness, a commonly used statistical parameter. Our preliminary results show that this method of assessment appears to be more accurate and robust than currently utilized methods which involve looking at percentages of radiodensities in air passages of the lung.

  19. Diagnostic imaging in thyrotoxicosis.

    PubMed

    Summaria, V; Salvatori, M; Rufini, V; Mirk, P; Garganese, M C; Romani, M

    1999-01-01

    In thyrotoxicosis, imaging mainly scintigraphy, color Doppler sonography and radioiodine uptake test are used in the differential diagnosis as well as in the morphofunctional evaluation of the thyroid before and after therapy (mainly pharmacological or with radioiodine). Radioiodine uptake test differentiates high uptake thyrotoxicosis (Graves'disease, toxic nodular goiter) and low uptake thyrotoxycosis (subacute or silent thyroiditis, ectopic thyrotoxicosis, iodine-induced hyperthyroidism). In Graves'disease scintigraphy shows thyroid enlargement with intense homogeneous tracer uptake; rarely nodules with no uptake are present. On color Doppler sonography, a part from enlargement, typical findings are: diffuse structural hypoechogenicity (at times with echoic nodules), parenchymal hypervascularization ("thyroid inferno"), high systolic velocities (PSV > 70-100 cm/sec) in inferior thyroid arteries. Scintigraphy is the only method able to evidence an autonomously functioning thyroid nodule and stage it (in association to clinical findings and TSH, FT3, FT4 determination) as: toxic, non toxic (or pretoxic) and compensated, depending on whether there is inhibition of extranodular tissue. A scintigraphically "hot" nodule appears hypervascularized on color Doppler sonography (especially in the toxic or pre-toxic phase) with high PSV (> 50-70 cm/sec) in the ipsilateral inferior thyroid artery. The most reliable parameters in the evaluation of the therapeutic efficacy are: decreases in thyroid (Graves'disease) or nodular (autonomously functioning nodule) volume; decreased radioiodine uptake (Graves'disease); functional recovery of suppressed parenchyma (autonomously functioning nodule); decreased PSV in the inferior thyroid arteries.

  20. Image enhancement of digital periapical radiographs according to diagnostic tasks

    PubMed Central

    Choi, Jin-Woo; Han, Won-Jeong

    2014-01-01

    Purpose This study was performed to investigate the effect of image enhancement of periapical radiographs according to the diagnostic task. Materials and Methods Eighty digital intraoral radiographs were obtained from patients and classified into four groups according to the diagnostic tasks of dental caries, periodontal diseases, periapical lesions, and endodontic files. All images were enhanced differently by using five processing techniques. Three radiologists blindly compared the subjective image quality of the original images and the processed images using a 5-point scale. Results There were significant differences between the image quality of the processed images and that of the original images (P<0.01) in all the diagnostic task groups. Processing techniques showed significantly different efficacy according to the diagnostic task (P<0.01). Conclusion Image enhancement affects the image quality differently depending on the diagnostic task. And the use of optimal parameters is important for each diagnostic task. PMID:24701456

  1. Image enhancement of digital periapical radiographs according to diagnostic tasks.

    PubMed

    Choi, Jin-Woo; Han, Won-Jeong; Kim, Eun-Kyung

    2014-03-01

    This study was performed to investigate the effect of image enhancement of periapical radiographs according to the diagnostic task. Eighty digital intraoral radiographs were obtained from patients and classified into four groups according to the diagnostic tasks of dental caries, periodontal diseases, periapical lesions, and endodontic files. All images were enhanced differently by using five processing techniques. Three radiologists blindly compared the subjective image quality of the original images and the processed images using a 5-point scale. There were significant differences between the image quality of the processed images and that of the original images (P<0.01) in all the diagnostic task groups. Processing techniques showed significantly different efficacy according to the diagnostic task (P<0.01). Image enhancement affects the image quality differently depending on the diagnostic task. And the use of optimal parameters is important for each diagnostic task.

  2. Diagnostic imaging for aortic dissection.

    PubMed

    Kapustin, Andrew J; Litt, Harold I

    2005-01-01

    Diagnostic imaging for aortic dissection has dramatically changed in recent years. Previously, imaging consisted of conventional X-ray radiography, followed by invasive catheter angiography. Now imaging of dissection is performed primarily with multidetector CT, and to a lesser extent, with ultrasound and MRI. Catheter angiography is used primarily as a means of treating complications. Which modality to choose depends on patient factors, physician preference, and differences in availability of state-of-the-art equipment. All three modalities are highly accurate in experienced hands and have revolutionized the detection and evaluation of this condition.

  3. Diagnostic imaging in bovine orthopedics.

    PubMed

    Kofler, Johann; Geissbühler, Urs; Steiner, Adrian

    2014-03-01

    Although a radiographic unit is not standard equipment for bovine practitioners in hospital or field situations, ultrasound machines with 7.5-MHz linear transducers have been used in bovine reproduction for many years, and are eminently suitable for evaluation of orthopedic disorders. The goal of this article is to encourage veterinarians to use radiology and ultrasonography for the evaluation of bovine orthopedic disorders. These diagnostic imaging techniques improve the likelihood of a definitive diagnosis in every bovine patient but especially in highly valuable cattle, whose owners demand increasingly more diagnostic and surgical interventions that require high-level specialized techniques.

  4. Diagnostic efficacy of contrast-enhanced sonography by combined qualitative and quantitative analysis in breast lesions: a comparative study with magnetic resonance imaging.

    PubMed

    Wang, Lin; Du, Jing; Li, Feng-Hua; Fang, Hua; Hua, Jia; Wan, Cai-Feng

    2013-10-01

    The purpose of this study was to evaluate the diagnostic efficacy of contrast-enhanced sonography for differentiation of breast lesions by combined qualitative and quantitative analyses in comparison to magnetic resonance imaging (MRI). Fifty-six patients with American College of Radiology Breast Imaging Reporting and Data System category 3 to 5 breast lesions on conventional sonography were evaluated by contrast-enhanced sonography and MRI. A comparative analysis of diagnostic results between contrast-enhanced sonography and MRI was conducted in light of the pathologic findings. Pathologic analysis showed 26 benign and 30 malignant lesions. The predominant enhancement patterns of the benign lesions on contrast-enhanced sonography were homogeneous, centrifugal, and isoenhancement or hypoenhancement, whereas the patterns of the malignant lesions were mainly heterogeneous, centripetal, and hyperenhancement. The detection rates for perfusion defects and peripheral radial vessels in the malignant group were much higher than those in the benign group (P < .05). As to quantitative analysis, statistically significant differences were found in peak and time-to-peak values between the groups (P < .05). With pathologic findings as the reference standard, the sensitivity, specificity, and accuracy of contrast-enhanced sonography and MRI were 90.0%, 92.3%, 91.1% and 96.7%, 88.5%, and 92.9%, respectively. The two methods had a concordant rate of 87.5% (49 of 56), and the concordance test gave a value of κ = 0.75, indicating that there was high concordance in breast lesion assessment between the two diagnostic modalities. Contrast-enhanced sonography provided typical enhancement patterns and valuable quantitative parameters, which showed good agreement with MRI in diagnostic efficacy and may potentially improve characterization of breast lesions.

  5. Diagnostic accuracy of contrast-enhanced MR angiography and unenhanced proton MR imaging compared with CT pulmonary angiography in chronic thromboembolic pulmonary hypertension.

    PubMed

    Rajaram, Smitha; Swift, Andrew J; Capener, David; Telfer, Adam; Davies, Christine; Hill, Catherine; Condliffe, Robin; Elliot, Charles; Hurdman, Judith; Kiely, David G; Wild, Jim M

    2012-02-01

    To evaluate the diagnostic accuracy of contrast-enhanced MR angiography (CE-MRA) and the added benefit of unenhanced proton MR angiography compared with CT pulmonary angiography (CTPA) in patients with chronic thromboembolic disease (CTE). A 2 year retrospective study of 53 patients with chronic thromboembolic pulmonary hypertension who underwent CTPA and MRI for suspected pulmonary hypertension and a control group of 36 patients with no CT evidence of pulmonary embolism. The MRI was evaluated for CTE and the combined diagnostic accuracy of ce-MRA and unenhanced proton MRA was determined. CE-MRA generated lung perfusion maps were also assessed. The overall sensitivity and specificity of CE-MRA in diagnosing proximal and distal CTE were 98% and 94%, respectively. The sensitivity improved from 50% to 88% for central vessel disease when CE-MRA images were analysed with unenhanced proton MRA. The CE-MRA identified more stenoses (29/18), post-stenosis dilatation (23/7) and occlusions (37/29) compared with CTPA. The CE-MRA perfusion images showed a sensitivity of 92% for diagnosing CTE. CE-MRA has high sensitivity and specificity for diagnosing CTE. The sensitivity of CE-MRA for visualisation of adherent central and lobar thrombus significantly improves with the addition of unenhanced proton MRA which delineates the vessel wall.

  6. Appropriate use of diagnostic imaging

    SciTech Connect

    Palmer, P.E.S.; Cockshott, W.P.

    1984-11-16

    This article discusses ways in which more appropriate use can be made of roentgenography with a resulting decrease in radiation doses to the patient population. The authors recommend that fewer films be made and that traditional roentgenography be replaced with endoscopy, ultrasound, computerized tomography, or angiography where appropriate. They also recommend that medical schools and medical subspecialty groups study the World Health Organization document which provides indications for diagnostic imaging, the choice of procedure and the limitations of each.

  7. Comparative Soot Diagnostics: Preliminary Results

    NASA Technical Reports Server (NTRS)

    Urban, David L.; Griffin, DeVon W.; Gard, Melissa Y.

    1997-01-01

    The motivation for the Comparative Soot Diagnostics (CSD) experiment lies in the broad practical importance of understanding combustion generated particulate. Depending upon the circumstances, particulate matter can affect the durability and performance of combustion equipment, can be a pollutant, can be used to detect fires and, in the form of soot, can be the dominant source of radiant energy from flames. The nonbuoyant structure of most flames of practical interest makes understanding of soot processes in low gravity flames important to our ability to predict fire behavior on earth. These studies also have direct applications to fire safety in human-crew spacecraft, since smoke is the indicator used for automated detection in current spacecraft. In the earliest missions (Mercury, Gemini and Apollo), the crew quarters were so cramped that it was considered reasonable that the astronauts would rapidly detect any fire. The Skylab module, however, included approximately 20 UV-sensing fire detectors. The Space Shuttle has 9 particle-ionization smoke detectors in the mid-deck and flight deck and Spacelab has six additional particle-ionization smoke detectors. The designated detectors for the ISS are laser-diode, forward-scattering, smoke or particulate detectors. Current plans for the ISS call for two detectors in the open area of the module, and detectors in racks that have both cooling air flow and electrical power. Due to the complete absence of data concerning the nature of particulate and radiant emission from incipient and fully developed low-g fires, all three of these detector systems were designed based upon l-g test data and experience. As planned mission durations and complexity increase and the volume of spacecraft increases, the need for and importance of effective, crew-independent, fire detection grows significantly. To provide this level of protection, more knowledge is needed concerning low-gravity fire phenomena and, in particular, how they might be

  8. In Vivo Diagnostic Imaging Using Micro-CT: Sequential and Comparative Evaluation of Rodent Models for Hepatic/Brain Ischemia and Stroke

    PubMed Central

    Hayasaka, Naoto; Nagai, Nobuo; Kawao, Naoyuki; Niwa, Atsuko; Yoshioka, Yoshichika; Mori, Yuki; Shigeta, Hiroshi; Kashiwagi, Nobuo; Miyazawa, Masaaki; Satou, Takao; Higashino, Hideaki; Matsuo, Osamu; Murakami, Takamichi

    2012-01-01

    Background There is an increasing need for animal disease models for pathophysiological research and efficient drug screening. However, one of the technical barriers to the effective use of the models is the difficulty of non-invasive and sequential monitoring of the same animals. Micro-CT is a powerful tool for serial diagnostic imaging of animal models. However, soft tissue contrast resolution, particularly in the brain, is insufficient for detailed analysis, unlike the current applications of CT in the clinical arena. We address the soft tissue contrast resolution issue in this report. Methodology We performed contrast-enhanced CT (CECT) on mouse models of experimental cerebral infarction and hepatic ischemia. Pathological changes in each lesion were quantified for two weeks by measuring the lesion volume or the ratio of high attenuation area (%HAA), indicative of increased vascular permeability. We also compared brain images of stroke rats and ischemic mice acquired with micro-CT to those acquired with 11.7-T micro-MRI. Histopathological analysis was performed to confirm the diagnosis by CECT. Principal Findings In the models of cerebral infarction, vascular permeability was increased from three days through one week after surgical initiation, which was also confirmed by Evans blue dye leakage. Measurement of volume and %HAA of the liver lesions demonstrated differences in the recovery process between mice with distinct genetic backgrounds. Comparison of CT and MR images acquired from the same stroke rats or ischemic mice indicated that accuracy of volumetric measurement, as well as spatial and contrast resolutions of CT images, was comparable to that obtained with MRI. The imaging results were also consistent with the histological data. Conclusions This study demonstrates that the CECT scanning method is useful in rodents for both quantitative and qualitative evaluations of pathologic lesions in tissues/organs including the brain, and is also suitable for

  9. Recent Advancements in Microwave Imaging Plasma Diagnostics

    SciTech Connect

    H. Park; C.C. Chang; B.H. Deng; C.W. Domier; A.J.H. Donni; K. Kawahata; C. Liang; X.P. Liang; H.J. Lu; N.C. Luhmann, Jr.; A. Mase; H. Matsuura; E. Mazzucato; A. Miura; K. Mizuno; T. Munsat; K. and Y. Nagayama; M.J. van de Pol; J. Wang; Z.G. Xia; W-K. Zhang

    2002-03-26

    Significant advances in microwave and millimeter wave technology over the past decade have enabled the development of a new generation of imaging diagnostics for current and envisioned magnetic fusion devices. Prominent among these are revolutionary microwave electron cyclotron emission imaging (ECEI), microwave phase imaging interferometers, imaging microwave scattering and microwave imaging reflectometer (MIR) systems for imaging electron temperature and electron density fluctuations (both turbulent and coherent) and profiles (including transport barriers) on toroidal devices such as tokamaks, spherical tori, and stellarators. The diagnostic technology is reviewed, and typical diagnostic systems are analyzed. Representative experimental results obtained with these novel diagnostic systems are also presented.

  10. [Diagnostic imaging of thyroid tumor].

    PubMed

    Miyakawa, Megumi

    2012-11-01

    Recently, thyroid nodules are found frequently when other imaging test was performed, and selection of diagnostic methods and its handling have become a problem clinically. Although it is possible to differentiate the malignant tumor from benign one using B-mode ultrasound, it can be obtained more detailed information in combination of other modalities such as color Doppler and tissue elasticity imaging (elastography). The malignant B-mode findings are irregular shape, indistinct border, hypoechoic and inhomogeneous internal echo, and fine calcification. CT/MRI is useful to evaluate the extention of thyroid cancer to adjacent organs beyond the thyroid capsule. It is also useful to evaluate distant metastases to lung or brain of thyroid cancer. In nuclear medicine, 125I scintigraphy is used to measure thyroid uptake rate, 131I scintigraphy is used to investigate the distant metastasis of thyroid cancer. It is necessary to be careful that some false-positive cases exist in 18FDG-PET.

  11. [Over diagnostic imaging in cardiology].

    PubMed

    Carpeggiani, Clara

    2014-03-01

    Medical imaging is one of the major cause of rising health care costs. Diagnostic imaging has increased more rapidly than any other component of medical care. About 5 billion imaging tests are performed worldwide each year. According to recent estimates, at least one-third of all examinations are partially or totally inappropriate. Two out of 3 imaging tests employ ionizing radiations with radiology or nuclear medicine. The medical use of radiation is the largest man-made source of radiation exposure. Medical X-rays and γ-rays are a proven human carcinogen. The attributable long-term extra-risk of cancer due to diagnostic testing is around 10% in industrialized countries. Cardiologists prescribe and/or directly perform >50% of all imaging examinations, accounting for about two-thirds of the total effective dose given to patients. The dose of common cardiological examinations may be significant: 500 chest X-rays= a stress scintigraphy with sestamibi, 750 chest X-rays= a Multislice Computed Tomography, 1,000 chest X-rays= a coronary angiography and stenting. Unfortunately, few doctors are aware of the level of radiation their patients are exposed to during radiological tests and more intensive use of ionizing testing was not associated with greater awareness. Also as a consequence of unawareness, the rate of inappropriate examinations is unacceptably high in cardiology, even for procedures with high radiation load. Higher exposure doses correspond to higher long-term risks; there are no safe doses, and all doses add up in determining the cumulative risks over a lifetime. Doctors should make every effort so that «each patient should get the right imaging exam, at the right time, with the right radiation dose», as suggested by US Food and Drug Administration in the 2010 initiative to reduce unnecessary radiation exposure from medical imaging. This is best obtained through a systematic implementation of the "3 A's strategy" proposed by the International Atomic Energy

  12. Multidetector computed tomography for the evaluation of coronary artery disease; the diagnostic accuracy in calcified coronary arteries, comparing with IVUS imaging.

    PubMed

    Park, Jong Kwan; Kim, Jong Youn; Kwon, Hyuck Moon; Kim, Tae Hoon; Oh, Seung-Jin; Hong, Bum-Kee; Yoon, Young Won; Min, Pil-Ki; Kwon, Sung Woo; Lee, Byoung Kwon

    2014-05-01

    Contrast enhanced multidetector computed tomography (MDCT) has been used as an alternative to coronary angiography for the assessment of coronary artery disease in the patient of the intermediate risk group. However, coronary calcium is a known limiting factor for MDCT evaluation. We investigated the diagnostic accuracy of 64-channel MDCT with each coronary artery calcium score (CACS) by compared with intravascular ultrasound (IVUS) imaging. A total of 54 symptomatic patients with intermediate-risk (10 females, mean age 59.9±6.9 years, Framingham point scores 9-20) with 162 sites who had a culprit lesion on 64-channel MDCT before performing coronary angiography with IVUS were enrolled. Patients were divided into 4 subgroups depending on CACS: 0, 1-99, 100-399, and >400. Lesion length, external elastic membrane (EEM) cross sectional area (CSA), minimal luminal area, and plaque area were measured and compared between IVUS and MDCT. The correlation coefficients for the measurements of the EEM CSA, lumen CSA, and plaque area were r=0.514, r=0.837, and r=0.578, respectively. Furthermore, there were close correlation of plaque area between four subgroups of CACS (r=0.671, r=0.623, r=0.562, r=0.571, respectively). Despite the increase in CACS, the geometric analysis of coronary arteries using with 64-channel MDCT was comparable with IVUS in symptomatic patient of the intermediate risk group.

  13. Multidetector Computed Tomography for the Evaluation of Coronary Artery Disease; The Diagnostic Accuracy in Calcified Coronary Arteries, Comparing with IVUS Imaging

    PubMed Central

    Park, Jong Kwan; Kim, Jong Youn; Kwon, Hyuck Moon; Kim, Tae Hoon; Oh, Seung-Jin; Hong, Bum-Kee; Yoon, Young Won; Min, Pil-Ki; Kwon, Sung Woo

    2014-01-01

    Purpose Contrast enhanced multidetector computed tomography (MDCT) has been used as an alternative to coronary angiography for the assessment of coronary artery disease in the patient of the intermediate risk group. However, coronary calcium is a known limiting factor for MDCT evaluation. We investigated the diagnostic accuracy of 64-channel MDCT with each coronary artery calcium score (CACS) by compared with intravascular ultrasound (IVUS) imaging. Materials and Methods A total of 54 symptomatic patients with intermediate-risk (10 females, mean age 59.9±6.9 years, Framingham point scores 9-20) with 162 sites who had a culprit lesion on 64-channel MDCT before performing coronary angiography with IVUS were enrolled. Patients were divided into 4 subgroups depending on CACS: 0, 1-99, 100-399, and >400. Lesion length, external elastic membrane (EEM) cross sectional area (CSA), minimal luminal area, and plaque area were measured and compared between IVUS and MDCT. Results The correlation coefficients for the measurements of the EEM CSA, lumen CSA, and plaque area were r=0.514, r=0.837, and r=0.578, respectively. Furthermore, there were close correlation of plaque area between four subgroups of CACS (r=0.671, r=0.623, r=0.562, r=0.571, respectively). Conclusion Despite the increase in CACS, the geometric analysis of coronary arteries using with 64-channel MDCT was comparable with IVUS in symptomatic patient of the intermediate risk group. PMID:24719125

  14. [Diagnostic imaging of splenic disease].

    PubMed

    Völk, M; Strotzer, M

    2006-03-01

    Primary diseases of the spleen are relatively rare. More frequently, the spleen is involved secondarily in hematological, oncological, infectious, immunological, vascular, and other systemic diseases. The spleen is the most commonly injured organ in blunt abdominal trauma. Anatomical and physiological basics are explained, in addition to embryological facts with resulting abnormalities, such as accessory and "wandering" spleen, and polysplenia. The most frequent primary and secondary diseases of the spleen, including rare diagnoses, are presented and illustrated. Hemangioma represents the most common primary benign tumor, and lymphoma the most common primary malignant tumor of the spleen. Diagnostic imaging does not a allow safe differentiation between Hodgkin's and non-Hodgkin's lymphoma. One section deals with the clinical value and diagnostic workup of incidentally detected lesions. Simple cysts and calcifications need neither clarification nor a follow-up examination. Atypical cysts should be controlled within 3-6 months. Additional clarification using CT or MRT should be reserved for cases with a strong suspicion of clinically relevant primary or secondary splenic disease.

  15. Diagnostic performance and comparative cost-effectiveness of non-invasive imaging tests in patients presenting with chronic stable chest pain with suspected coronary artery disease: a systematic overview.

    PubMed

    van Waardhuizen, Claudia N; Langhout, Marieke; Ly, Felisia; Braun, Loes; Genders, Tessa S S; Petersen, Steffen E; Fleischmann, Kirsten E; Nieman, Koen; Hunink, M G Myriam

    2014-01-01

    Several non-invasive imaging techniques are currently in use for the diagnostic workup of adult patients with stable chest pain suspected of having coronary artery disease (CAD). In this paper, we present a systematic overview of the evidence on diagnostic performance and comparative cost-effectiveness of new modalities in comparison to established technologies. A literature search for English language studies from 2009 to 2013 was performed, and two investigators independently extracted data on patient and study characteristics. The reviewed published evidence on diagnostic performance and cost-effectiveness support a strategy of CTCA as a rule out (gatekeeper) test of CAD in low- to intermediate-risk patients since it has excellent diagnostic performance and as initial imaging test is cost-effective under different willingness-to-pay thresholds. More cost-effectiveness research is needed in order to define the role and choice of cardiac stress imaging tests.

  16. Myocardial fibrosis imaging based on T1-mapping and extracellular volume fraction (ECV) measurement in muscular dystrophy patients: diagnostic value compared with conventional late gadolinium enhancement (LGE) imaging.

    PubMed

    Florian, Anca; Ludwig, Anna; Rösch, Sabine; Yildiz, Handan; Sechtem, Udo; Yilmaz, Ali

    2014-09-01

    Cardiac involvement with progressive myocardial fibrosis leading to dilated cardiomyopathy is a major cause of death in muscular dystrophy patients. Extracellular volume fraction (ECV) measurement based on T1-mapping pre- and post-contrast promises the detection of early 'diffuse' myocardial fibrosis that cannot be depicted by conventional contrast-imaging based on late gadolinium enhancement (LGE). With this study, we evaluated the presence of diffuse myocardial fibrosis in regions of 'normal' (LGE-negative) and 'diseased' (LGE-positive) appearing myocardium as well as its relation to the extent of left ventricular (LV) dysfunction and the occurrence of arrhythmias in Becker muscular dystrophy (BMD) patients. Twenty-seven BMD patients (35 ± 12 years) and 17 matched male healthy controls (33 ± 8 years) underwent cardiovascular magnetic resonance (CMR) studies including ECV measurement and LGE-imaging. Ambulatory monitoring of arrhythmic events was performed by means of an external event loop recorder. Twenty BMD patients (74%) demonstrated cardiac involvement as detected by typical inferolateral presence of LGE. Twelve patients (44%) had an impaired LV ejection fraction-all being LGE-positive. Global myocardial ECV was significantly higher in the BMD group (29 ± 6%) compared with the control group (24 ± 2%, P = 0.001). Patients with cardiac involvement demonstrated higher global ECV (31 ± 6%) as well as significantly increased regional ECV not only in LGE-positive segments (34 ± 6%), but also in LGE-negative segments (28 ± 6%) compared with BMD patients without cardiac involvement and to controls, respectively (24 ± 3 and 24 ± 2%, P = 0.005). Global ECV in patients with cardiac involvement substantially correlated to LV ejection fraction (r = -0.629, P = 0.003) and to the number of LGE-positive segments (r = 0.783, P < 0.001). On univariable analysis, global ECV-but not the categorical presence of LGE per se--was significantly associated with arrhythmic

  17. Parkinson's disease: diagnostic utility of volumetric imaging.

    PubMed

    Lin, Wei-Che; Chou, Kun-Hsien; Lee, Pei-Lin; Tsai, Nai-Wen; Chen, Hsiu-Ling; Hsu, Ai-Ling; Chen, Meng-Hsiang; Huang, Yung-Cheng; Lin, Ching-Po; Lu, Cheng-Hsien

    2017-04-01

    This paper aims to examine the effectiveness of structural imaging as an aid in the diagnosis of Parkinson's disease (PD). High-resolution T 1-weighted magnetic resonance imaging was performed in 72 patients with idiopathic PD (mean age, 61.08 years) and 73 healthy subjects (mean age, 58.96 years). The whole brain was parcellated into 95 regions of interest using composite anatomical atlases, and region volumes were calculated. Three diagnostic classifiers were constructed using binary multiple logistic regression modeling: the (i) basal ganglion prior classifier, (ii) data-driven classifier, and (iii) basal ganglion prior/data-driven hybrid classifier. Leave-one-out cross validation was used to unbiasedly evaluate the predictive accuracy of imaging features. Pearson's correlation analysis was further performed to correlate outcome measurement using the best PD classifier with disease severity. Smaller volume in susceptible regions is diagnostic for Parkinson's disease. Compared with the other two classifiers, the basal ganglion prior/data-driven hybrid classifier had the highest diagnostic reliability with a sensitivity of 74%, specificity of 75%, and accuracy of 74%. Furthermore, outcome measurement using this classifier was associated with disease severity. Brain structural volumetric analysis with multiple logistic regression modeling can be a complementary tool for diagnosing PD.

  18. The value of diagnostic medical imaging.

    PubMed

    Bradley, Don; Bradley, Kendall E

    2014-01-01

    Diagnostic medical imaging has clear clinical utility, but it also imposes significant costs on the health care system. This commentary reviews the factors that drive the cost of medical imaging, discusses current interventions, and suggests possible future courses of action.

  19. Ferroelectric optical image comparator

    DOEpatents

    Butler, M.A.; Land, C.E.; Martin, S.J.; Pfeifer, K.B.

    1993-11-30

    A ferroelectric optical image comparator has a lead lanthanum zirconate titanate thin-film device which is constructed with a semi-transparent or transparent conductive first electrode on one side of the thin film, a conductive metal second electrode on the other side of the thin film, and the second electrode is in contact with a nonconducting substrate. A photoinduced current in the device represents the dot product between a stored image and an image projected onto the first electrode. One-dimensional autocorrelations are performed by measuring this current while displacing the projected image. 7 figures.

  20. Ferroelectric optical image comparator

    DOEpatents

    Butler, Michael A.; Land, Cecil E.; Martin, Stephen J.; Pfeifer, Kent B.

    1993-01-01

    A ferroelectric optical image comparator has a lead lanthanum zirconate titanate thin-film device which is constructed with a semi-transparent or transparent conductive first electrode on one side of the thin film, a conductive metal second electrode on the other side of the thin film, and the second electrode is in contact with a nonconducting substrate. A photoinduced current in the device represents the dot product between a stored image and an image projected onto the first electrode. One-dimensional autocorrelations are performed by measuring this current while displacing the projected image.

  1. Diagnostic imaging of the acutely injured patient

    SciTech Connect

    Berquist, T.H.

    1985-01-01

    This book provides an analysis of pathophysiologic concepts of trauma and reviews the effectiveness of the available imaging modalities in acute trauma of various organ system. Topics covered are chest injuries; abdominal trauma; fractures of long bones; the foot and ankle; the knee; hand and wrist; the elbow; the shoulder; the pelvis hips; the spine; the skull and facial trauma and the clinical assessment of multiple injuries patients. Comparative evaluation of diagnostic techniques of radiography is discussed. Normal anatomy and bone fractures along with soft-tissue injuries are described.

  2. Vestibular migraine: comparative analysis between diagnostic criteria.

    PubMed

    Salmito, Márcio Cavalcante; Morganti, Lígia Oliveira Gonçalves; Nakao, Bruno Higa; Simões, Juliana Caminha; Duarte, Juliana Antoniolli; Ganança, Fernando Freitas

    2015-01-01

    There is a strong association between vertigo and migraine. Vestibular migraine (VM) was described in 1999, and diagnostic criteria were proposed in 2001 and revised in 2012. To compare the diagnostic criteria for VM proposed in 2001 with 2012 criteria with respect to their diagnostic power and therapeutic effect of VM prophylaxis. Clinical chart review of patients attended to in a VM clinic. The 2012 criteria made the diagnosis more specific, restricting the diagnosis of VM to a smaller number of patients, such that 87.7% of patients met 2001 criteria and 77.8% met 2012 criteria. Prophylaxis for VM was effective both for patients diagnosed by either set of criteria and for those who did not meet any of the criteria. The 2012 diagnostic criteria for VM limited the diagnosis of the disease to a smaller number of patients, mainly because of the type, intensity, and duration of dizziness. Patients diagnosed with migraine and associated dizziness demonstrated improvement after prophylactic treatment of VM, even when they did not meet diagnostic criteria. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  3. Choosing the right diagnostic imaging modality in musculoskeletal diagnosis.

    PubMed

    Aagesen, Andrea L; Melek, Maged

    2013-12-01

    Radiological studies can confirm or rule out competing diagnoses for musculoskeletal injuries and pain. Obtaining a detailed history and physical examination is pivotal for localizing the pain generator and choosing the most appropriate imaging studies, based on the suspected injured tissue. Judicious use of imaging is important to avoid unnecessary radiation exposure, minimize cost, and avoid therapy targeting asymptomatic imaging abnormalities. This article compares and contrasts the diagnostic imaging commonly used for detecting musculoskeletal injuries. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Managing waiting times in diagnostic medical imaging

    PubMed Central

    Nuti, Sabina; Vainieri, Milena

    2012-01-01

    Objective This paper aims to analyse the variation in the delivery of diagnostic imaging services in order to suggest possible solutions for the reduction of waiting times, increase the quality of services and reduce financial costs. Design This study provides a logic model to manage waiting times in a regional context. Waiting times measured per day were compared on the basis of the variability in the use rates of CT and MRI examinations in Tuscany for the population, as well as on the basis of the capacity offered with respect to the number of radiologists available. The analysis was performed at the local health authority level to support the decision-making process of local managers. Setting Diagnostic imaging services, in particular the CT and MRI examinations. The study involved all the 12 local health authorities that provide services for 3.7 million inhabitants of the Italian Tuscany Region. Primary and secondary outcome measures Participants: the study uses regional administrative data on outpatients and survey data on inpatient diagnostic examinations in order to measure productivity. Primary and secondary outcome measures The study uses the volumes per 1000 inhabitants, the days of waiting times and the number of examinations per radiologist. Variability was measured using the traditional SD measures. Results A significant variation in areas considered homogeneous in terms of age, gender or mortality may indicate that the use of radiological services is not optimal and underuse or overuse occurs and that there is room for improvement in the service organisation. Conclusions Considering that there is a high level of variability among district use rates and waiting times, this study provides managers with a specific tool to find the cause of the problem, identify a possible solution, assess the financial impact and initiate the eventual reduction of waste. PMID:23242480

  5. Clinics in diagnostic imaging (174)

    PubMed Central

    Subramanian, Manickam; Chou, Hong; Chokkappan, Kabilan; Peh, Wilfred CG

    2017-01-01

    A 25-year-old man presented with chronic low back pain and occasional radiation to the right lower limb. Magnetic resonance imaging and computed tomography (CT) of the lumbar spine showed an osteolytic expansile lesion with a central sclerotic nidus in the right superior facet of the L5 vertebra and surrounding marrow oedema. The diagnosis of osteoblastoma was made based on imaging findings and confirmed after CT-guided biopsy. Radiofrequency ablation of the lesion was successfully performed. The patient tolerated the procedure well and showed symptomatic relief. The imaging features and management of osteoblastoma are discussed. PMID:28210742

  6. The neutron imaging diagnostic at NIF (invited).

    PubMed

    Merrill, F E; Bower, D; Buckles, R; Clark, D D; Danly, C R; Drury, O B; Dzenitis, J M; Fatherley, V E; Fittinghoff, D N; Gallegos, R; Grim, G P; Guler, N; Loomis, E N; Lutz, S; Malone, R M; Martinson, D D; Mares, D; Morley, D J; Morgan, G L; Oertel, J A; Tregillis, I L; Volegov, P L; Weiss, P B; Wilde, C H; Wilson, D C

    2012-10-01

    A neutron imaging diagnostic has recently been commissioned at the National Ignition Facility (NIF). This new system is an important diagnostic tool for inertial fusion studies at the NIF for measuring the size and shape of the burning DT plasma during the ignition stage of Inertial Confinement Fusion (ICF) implosions. The imaging technique utilizes a pinhole neutron aperture, placed between the neutron source and a neutron detector. The detection system measures the two dimensional distribution of neutrons passing through the pinhole. This diagnostic has been designed to collect two images at two times. The long flight path for this diagnostic, 28 m, results in a chromatic separation of the neutrons, allowing the independently timed images to measure the source distribution for two neutron energies. Typically the first image measures the distribution of the 14 MeV neutrons and the second image of the 6-12 MeV neutrons. The combination of these two images has provided data on the size and shape of the burning plasma within the compressed capsule, as well as a measure of the quantity and spatial distribution of the cold fuel surrounding this core.

  7. Diagnostic imaging and radiation exposure in inflammatory bowel disease

    PubMed Central

    Zakeri, Nekisa; Pollok, Richard CG

    2016-01-01

    Diagnostic imaging plays a key role in the diagnosis and management of inflammatory bowel disease (IBD). However due to the relapsing nature of IBD, there is growing concern that IBD patients may be exposed to potentially harmful cumulative levels of ionising radiation in their lifetime, increasing malignant potential in a population already at risk. In this review we explore the proportion of IBD patients exposed to high cumulative radiation doses, the risk factors associated with higher radiation exposures, and we compare conventional diagnostic imaging with newer radiation-free imaging techniques used in the evaluation of patients with IBD. While computed tomography (CT) performs well as an imaging modality for IBD, the effective radiation dose is considerably higher than other abdominal imaging modalities. It is increasingly recognised that CT imaging remains responsible for the majority of diagnostic medical radiation to which IBD patients are exposed. Magnetic resonance imaging (MRI) and small intestine contrast enhanced ultrasonography (SICUS) have now emerged as suitable radiation-free alternatives to CT imaging, with comparable diagnostic accuracy. The routine use of MRI and SICUS for the clinical evaluation of patients with known or suspected small bowel Crohn’s disease is to be encouraged wherever possible. More provision is needed for out-of-hours radiation-free imaging modalities to reduce the need for CT. PMID:26900282

  8. Diagnostic imaging and radiation exposure in inflammatory bowel disease.

    PubMed

    Zakeri, Nekisa; Pollok, Richard C G

    2016-02-21

    Diagnostic imaging plays a key role in the diagnosis and management of inflammatory bowel disease (IBD). However due to the relapsing nature of IBD, there is growing concern that IBD patients may be exposed to potentially harmful cumulative levels of ionising radiation in their lifetime, increasing malignant potential in a population already at risk. In this review we explore the proportion of IBD patients exposed to high cumulative radiation doses, the risk factors associated with higher radiation exposures, and we compare conventional diagnostic imaging with newer radiation-free imaging techniques used in the evaluation of patients with IBD. While computed tomography (CT) performs well as an imaging modality for IBD, the effective radiation dose is considerably higher than other abdominal imaging modalities. It is increasingly recognised that CT imaging remains responsible for the majority of diagnostic medical radiation to which IBD patients are exposed. Magnetic resonance imaging (MRI) and small intestine contrast enhanced ultrasonography (SICUS) have now emerged as suitable radiation-free alternatives to CT imaging, with comparable diagnostic accuracy. The routine use of MRI and SICUS for the clinical evaluation of patients with known or suspected small bowel Crohn's disease is to be encouraged wherever possible. More provision is needed for out-of-hours radiation-free imaging modalities to reduce the need for CT.

  9. Hierarchical Segmentation Enhances Diagnostic Imaging

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Bartron Medical Imaging LLC (BMI), of New Haven, Connecticut, gained a nonexclusive license from Goddard Space Flight Center to use the RHSEG software in medical imaging. To manage image data, BMI then licensed two pattern-matching software programs from NASA's Jet Propulsion Laboratory that were used in image analysis and three data-mining and edge-detection programs from Kennedy Space Center. More recently, BMI made NASA history by being the first company to partner with the Space Agency through a Cooperative Research and Development Agreement to develop a 3-D version of RHSEG. With U.S. Food and Drug Administration clearance, BMI will sell its Med-Seg imaging system with the 2-D version of the RHSEG software to analyze medical imagery from CAT and PET scans, MRI, ultrasound, digitized X-rays, digitized mammographies, dental X-rays, soft tissue analyses, moving object analyses, and soft-tissue slides such as Pap smears for the diagnoses and management of diseases. Extending the software's capabilities to three dimensions will eventually enable production of pixel-level views of a tumor or lesion, early identification of plaque build-up in arteries, and identification of density levels of microcalcification in mammographies.

  10. Clinics in diagnostic imaging (175)

    PubMed Central

    Krishnan, Vijay; Lim, Tze Chwan; Ho, Francis Cho Hao; Peh, Wilfred CG

    2017-01-01

    A 54-year-old man presented with change in behaviour, nocturnal enuresis, abnormal limb movement and headache of one week’s duration. The diagnosis of butterfly glioma (glioblastoma multiforme) was made based on imaging characteristics and was further confirmed by biopsy findings. As the corpus callosum is usually resistant to infiltration by tumours, a mass that involves and crosses the corpus callosum is suggestive of an aggressive neoplasm. Other neoplastic and non-neoplastic conditions that may involve the corpus callosum and mimic a butterfly glioma, as well as associated imaging features, are discussed. PMID:28361164

  11. The pacing stress test: thallium-201 myocardial imaging after atrial pacing. Diagnostic value in detecting coronary artery disease compared with exercise testing

    SciTech Connect

    Heller, G.V.; Aroesty, J.M.; Parker, J.A.; McKay, R.G.; Silverman, K.J.; Als, A.V.; Come, P.C.; Kolodny, G.M.; Grossman, W.

    1984-05-01

    Many patients suspected of having coronary artery disease are unable to undergo adequate exercise testing. An alternate stress, pacing tachycardia, has been shown to produce electrocardiographic changes that are as sensitive and specific as those observed during exercise testing. To compare thallium-201 imaging after atrial pacing stress with thallium imaging after exercise stress, 22 patients undergoing cardiac catheterization were studied with both standard exercise thallium imaging and pacing thallium imaging. Positive ischemic electrocardiographic changes (greater than 1 mm ST segment depression) were noted in 11 of 16 patients with coronary artery disease during exercise, and in 15 of the 16 patients during atrial pacing. One of six patients with normal or trivial coronary artery disease had a positive electrocardiogram with each test. Exercise thallium imaging was positive in 13 of 16 patients with coronary artery disease compared with 15 of 16 patients during atrial pacing. Three of six patients without coronary artery disease had a positive scan with exercise testing, and two of these same patients developed a positive scan with atrial pacing. Of those patients with coronary artery disease and an abnormal scan, 85% showed redistribution with exercise testing compared with 87% during atrial pacing. Segment by segment comparison of thallium imaging after either atrial pacing or exercise showed that there was a good correlation of the location and severity of the thallium defects (r . 0.83, p . 0.0001, Spearman rank correlation). It is concluded that the location and presence of both fixed and transient thallium defects after atrial pacing are closely correlated with the findings after exercise testing.

  12. Diagnostic cardiology: Noninvasive imaging techniques

    SciTech Connect

    Come, P.C.

    1985-01-01

    This book contains 23 chapters. Some of the chapter titles are: The chest x-ray and cardiac series; Computed tomographic scanning of the heart, coronary arteries, and great vessels; Digital subtraction angiography in the assessment of cardiovascular disease; Magnetic resonance: technique and cardiac applications; Basics of radiation physics and instrumentation; and Nuclear imaging: the assessment of cardiac performance.

  13. Clinics in diagnostic imaging (172)

    PubMed Central

    Low, Hsien Min; Chinchure, Dinesh

    2016-01-01

    A 50-year-old Chinese man presented with abdominal pain associated with bloody mucoid stools, loss of appetite and weight loss. Contrast-enhanced computed tomography of the abdomen and pelvis revealed a colocolic intussusception secondary to a lipoma. The patient subsequently underwent a left hemicolectomy. Clinical and imaging findings of intussusception in adults are discussed in this article. PMID:27995264

  14. [Diagnostic imaging and acute abdominal pain].

    PubMed

    Liljekvist, Mads Svane; Pommergaard, Hans-Christian; Burcharth, Jakob; Rosenberg, Jacob

    2015-01-19

    Acute abdominal pain is a common clinical condition. Clinical signs and symptoms can be difficult to interpret, and diagnostic imaging may help to identify intra-abdominal disease. Conventional X-ray, ultrasound (US) and computed tomography (CT) of the abdomen vary in usability between common surgical causes of acute abdominal pain. Overall, conventional X-ray cannot confidently diagnose or rule out disease. US and CT are equally trustworthy for most diseases. US with subsequent CT may enhance diagnostic precision. Magnetic resonance seems promising for future use in acute abdominal imaging.

  15. Neuroblastoma: diagnostic imaging and staging

    SciTech Connect

    Stark, D.D.; Moss, A.A.; Brasch, R.C.; deLorimier, A.A.; Albin, A.R.; London, D.A.; Gooding, C.A.

    1983-07-01

    Results of computed tomography (CT), scintigraphy, excretory urography, and other imaging tests used to diagnose and stage 38 cases of neuroblastoma prior to treatment were reviewed. Findings of these examinations were correlated with clinical data, laboratory data, results of biopsy, and surgical findings. CT was the most sensitive single test (100%) for the detection and delineation of the primary tumor. Calcifications that suggested the histologic diagnosis of neuroblastoma were present in 79% of the cases. Rim calcifications, the most specific pattern for neuroblastoma, were identified in 29% of all cases. CT alone accurately staged 82% of cases; when complemented by bone marrow biopsy, staging accuracy was 97%. CT alone was more accurate than any combination of imaging tests that excluded CT. An algorithm using CT is presented for the diagnosis and staging of neuroblastoma at reduced cost and with increased efficiency.

  16. Clinics in diagnostic imaging (171)

    PubMed Central

    Ooi, Su Kai Gideon; Tan, Tien Jin; Ngu, James Chi Yong

    2016-01-01

    A 46-year-old Chinese woman with a history of cholecystectomy and appendicectomy presented to the emergency department with symptoms of intestinal obstruction. Physical examination revealed central abdominal tenderness but no clinical features of peritonism. Plain radiography of the abdomen revealed a grossly distended large bowel loop with the long axis extending from the right lower abdomen toward the epigastrium, and an intraluminal air-fluid level. These findings were suspicious for an acute caecal volvulus, which was confirmed on subsequent contrast-enhanced computed tomography (CT) of the abdomen and pelvis. CT demonstrated an abnormal positional relationship between the superior mesenteric vein and artery, indicative of an underlying intestinal malrotation. This case highlights the utility of preoperative imaging in establishing the diagnosis of an uncommon cause of bowel obstruction. It also shows the importance of recognising the characteristic imaging features early, so as to ensure appropriate and expedient management, thus reducing patient morbidity arising from complications. PMID:27872936

  17. Optical Diagnostic Imaging Of Surface Topography And Body Deformity

    NASA Astrophysics Data System (ADS)

    Windischbauer, Gerhard

    1989-04-01

    Modern diagnostic imaging techniques are providing three-dimensional images by the combination of analog sensing devices, powerful digital processors and graphic displays. Computer based optical imaging systems are used for detection and tracking of body deformities in Orthopaedics. To establish a morphometric data-base means for comparing and averaging similar shapes have to be prepared. Assuming fast technological advancements use at present and prospective applications are given.

  18. Clinics in diagnostic imaging (173)

    PubMed Central

    Gaikwad, Vishal; Chawla, Ashish; Lim, Tze Chwan; Peh, Wilfred CG

    2017-01-01

    A 56-year-old Chinese man presented with giddiness and vertigo. Subsequent chest radiography showed the classic scimitar sign of an abnormal pulmonary venous return. Further evaluation with non-contrast computed tomography substantiated the finding of a partial anomalous venous drainage pattern and identified an associated rare lung anomaly, horseshoe lung. The imaging findings of scimitar syndrome and its association with horseshoe lung are reviewed. PMID:28111692

  19. [Diagnostic imaging of bone metastases].

    PubMed

    Scutellari, P N; Addonisio, G; Righi, R; Giganti, M

    2000-12-01

    To present an "algorithm" for detection and diagnosis of skeletal metastases, which may be applied differently in symptomatic and asymptomatic cancer patients. February to March 1999 we randomly selected and retrospectively reviewed the clinical charts of 100 cancer patients (70 women and 30 men; mean age: 63 years, range: 55-87). All the patients had been staged according to TNM criteria and had undergone conventional radiography and bone scan; when findings were equivocal, CT and MRI had been performed too. The primary lesions responsible for bone metastases were sited in the: breast (51 cases), colon (30 cases: 17 men and 13 women), lung (7 cases: 6 men and 1 woman), stomach (4 cases: 2 men and 2 women), skin (4 cases: 3 men and 1 woman), kidney (2 men), pleura (1 woman), and finally liver (1 men). The most frequent radiographic pattern was the lytic type (52%), followed by osteosclerotic, mixed, lytic vs. mixed and osteosclerotic vs lytic patterns. The patients were divided into two groups: group A patients were asymptomatic and group B patients had local symptoms and/or pain. Skeletal metastases are the most common malignant bone tumors: the spine and the pelvis are the most frequent sites of metastasis, because of the presence of high amounts of red (hematopoietic active) bone marrow. Pain is the main symptom, even though many bone metastases are asymptomatic. Pathological fractures are the most severe consequences. With the algorithm for detection and diagnosis of skeletal metastases two different diagnostic courses are available for asymptomatic and symptomatic patients. Bone scintigraphy remains the technique of choice in asymptomatic patients in whom skeletal metastases are suspected. However this technique, though very sensitive, is poorly specific, and thus a negative bone scan finding is double-checked with another physical examination: if the findings remain negative, the diagnostic workup is over. On the contrary, in patients with a positive bone

  20. [Inflammatory bowel diseases--imaging diagnostics].

    PubMed

    Gil, Jerzy; Wojtuń, Stanisław; Stec-Michalska, Krystyna; Chojnacki, Cezary

    2004-01-01

    The basic diagnostic procedure in ulcerative colitis is an endoscopy of gastrointestinal tract. It allows the macroscopic evaluation as well as the specimen taking for histological assessment what is the basis for ultimate diagnosis. In case of Crohn's disease the radiological diagnostics is of equal importance as endoscope evaluation. The imaging of inflammatory changes in Crohn's disease still poses some difficulties, especially, that located in the small intestine. Lately, the range of accessible examinations has been wider. We have in disposal the ultrasonography, the computed tomography, the magnetic resonance imaging and the capsular endoscopy. All of them are of great use in the diagnosis of Crohn's disease. In case of microscopic colitis all the imaging diagnostics has no use. The only one mean to establish the diagnosis is a histological assessment. What is more, in the period of remission the colon tissue could be normal. In this paper we discussed the traditional and contemporary intestine imaging methods in inflammatory bowel diseases. The conclusion is that the further progress in science offers a better imaging and, what is even more important, the more efficient diagnostics and treatment of these diseases.

  1. [Invasive diagnostic imaging of coronary atherosclerosis].

    PubMed

    Gamou, Tadatsugu; Kawashiri, Masaaki; Tada, Hayato; Hayashi, Kenshi; Yamagishi, Masakazu

    2011-01-01

    Invasive diagnostic imaging technique of coronary atherosclerosis has rapidly developed. For example, intravascular ultrasound(IVUS) is recognized as an essential device for percutaneous coronary intervention to evaluate the vessel wall, vascular lumen and coronary plaque morphologies because of its accuracy for quantitative analysis capability. Recently new imaging modalities such as radio-frequency signal analysis, elastography and contrast harmonic echography have been developed for the evaluation of histological characteristics. Also, optical coherence tomography(OCT), which provides approximately ten-times higher-resolutional cross-section images of the coronary arterial wall in comparison with IVUS, became available in clinical setting. In this article, we review the latest progress of the invasive diagnostic imaging of coronary atherosclerosis.

  2. Hepatocellular carcinoma: Advances in diagnostic imaging.

    PubMed

    Sun, Haoran; Song, Tianqiang

    2015-10-01

    Thanks to the growing knowledge on biological behaviors of hepatocellular carcinomas (HCC), as well as continuous improvement in imaging techniques and experienced interpretation of imaging features of the nodules in cirrhotic liver, the detection and characterization of HCC has improved in the past decade. A number of practice guidelines for imaging diagnosis have been developed to reduce interpretation variability and standardize management of HCC, and they are constantly updated with advances in imaging techniques and evidence based data from clinical series. In this article, we strive to review the imaging techniques and the characteristic features of hepatocellular carcinoma associated with cirrhotic liver, with emphasis on the diagnostic value of advanced magnetic resonance imaging (MRI) techniques and utilization of hepatocyte-specific MRI contrast agents. We also briefly describe the concept of liver imaging reporting and data systems and discuss the consensus and controversy of major practice guidelines.

  3. Clinics in diagnostic imaging (168)

    PubMed Central

    Lai, Yusheng Keefe; Mahmood, Rameysh Danovani

    2016-01-01

    A 16-year-old Chinese male patient presented with constipation lasting five days, colicky abdominal pain, lethargy, weakness and body aches. He was able to pass flatus. Abdominal radiography showed a distended stomach causing inferior displacement of the transverse colon. Computed tomography revealed a dilated oesophagus, stomach and duodenum up to its third portion, with a short aortomesenteric distance and narrow angle. There was also consolidation in the lungs bilaterally. Based on the constellation of clinical and imaging findings, a diagnosis of superior mesenteric artery syndrome complicated by aspiration pneumonia was made. The patient was subsequently started on intravenous hydration, nasogastric tube aspiration and antibiotics. Following stabilisation of his acute condition, a nasojejunal feeding tube was inserted and a feeding plan was implemented to promote weight gain. The clinical presentation, differentials, diagnosis and treatment of superior mesenteric artery syndrome are discussed. PMID:27212130

  4. Clinics in diagnostic imaging (170)

    PubMed Central

    Shah, Mohammad Taufik Bin Mohamed; Wong, Bak Siew Steven

    2016-01-01

    A 30-year-old woman presented with a six-month history of left posterior heel pain. Physical examination revealed a tender, inflamed and indurated posterior heel with a visible bony prominence of the posterosuperior aspect of the calcaneus. Lateral ankle radiography showed a prominent left posterosuperior calcaneal tuberosity and thickening of the distal Achilles tendon outline. Magnetic resonance imaging demonstrated high-signal inflammatory fluid in the retrocalcaneal bursa, increased signal intensity and thickening of the Achilles tendon, and prominence of the posterior calcaneus tuberosity with reactive marrow oedema. The findings are consistent with Haglund’s deformity. The patient underwent hind foot surgery after failing a six-month course of conservative therapy. There was no further recurrence of symptoms after surgery. The clinical and radiological features of Haglund’s deformity are described, including a short discussion of other causes of hind foot pain. PMID:27663032

  5. Marketing considerations for diagnostic imaging centers.

    PubMed

    McCue, P

    1987-10-01

    Diagnostic imaging centers seek every possible advantage to maintain a successful practice in the face of competition from hospitals and other freestanding operators. Several radiologists and business managers involved in existing or planned centers discuss their marketing strategies, modality choices, organizational structure, and other issues pertinent to the start-up and operation of a viable free-standing operation.

  6. Exploiting EIS/Hinode Imaging Diagnostic Capabilities

    NASA Astrophysics Data System (ADS)

    Ugarte-Urra, Ignacio; Warren, H. P.

    2009-05-01

    Using a wide slit, also called slot, the Extreme-ultraviolet Imaging Spectrometer, on-board Hinode, is capable of obtaining relatively fast (1-3 min) simultaneous monochromatic images of various spectral lines with different formation temperatures ranging 0.4-3 MK. This mode allows us to study morphology and dynamics of solar coronal and transition region structures across the temperature spectrum in a similar way to an EUV imager. This is achieved at the expense of spectral resolution. In this paper we investigate the plasma diagnostic capabilities of these spectrally pure images.Wide slit images can be interpreted as a superposition of simultaneous narrow slit spectra from adjacent solar positions. From the comparison of consecutive narrow slit rasters and wide slit images, we demonstrate that by making simple assumptions it is possible to extract the narrow slit spectra out of the slot images. This encouraging result opens up the door for plasma diagnostics, like electron density from spectral line ratios and differential emission measure analysis, for solar dynamic events. Various examples, as well as the limitations and validity of the assumptions, are discussed.

  7. Computational Imaging, Sensing and Diagnostics for Global Health Applications

    PubMed Central

    Coskun, Ahmet F.; Ozcan, Aydogan

    2013-01-01

    In this Review, we summarize some of the recent work in emerging computational imaging, sensing and diagnostics techniques, along with some of the complementary non-computational modalities that can potentially transform the delivery of health care globally. As computational resources are becoming more and more powerful, while also getting cheaper and more widely available, traditional imaging, sensing and diagnostic tools will continue to experience a revolution through simplification of their designs, making them compact, light-weight, cost-effective, and yet quite powerful in terms of their performance when compared to their bench-top counterparts. PMID:24484875

  8. Spectroscopic imaging diagnostics for burning plasma experiments

    SciTech Connect

    Stutman, D.; Finkenthal, M.; Suliman, G.; Tritz, K.; Delgado-Aparicio, L.; Kaita, R.; Johnson, D.; Soukhanovskii, V.; May, M.J.

    2005-02-01

    Spectroscopic imaging of plasma emission profiles from a few electron volts to tens of kilo-electron volts enables basic diagnostics in present day tokamaks. For the more difficult burning plasma conditions, light extraction and detection techniques, as well as instrument designs need to be investigated. As an alternative to light extraction with reflective optics, we discuss normal incidence, transmissive-diffractive optics (e.g., transmission gratings), which might withstand plasma exposure with less degradation of optical properties. Metallic multilayer reflectors are also of interest for light extraction. Although a shift of the diffraction peak might occur, instrument designs that accommodate such shifts are possible. As imaging detectors we consider 'optical' arrays based on conversion of the short-wavelength light into visible light followed by transport of the visible signal with hollow lightguides. The proposed approaches to light extraction and detection could enable radiation resistant diagnostics.

  9. Hyperspectral fluorescence imaging system for biomedical diagnostics

    NASA Astrophysics Data System (ADS)

    Martin, Matthew E.; Wabuyele, Musundi B.; Panjehpour, Masoud; Phan, Mary N.; Overholt, Bergein F.; Vo-Dinh, Tuan

    2006-02-01

    An advanced hyper-spectral imaging (HSI) system has been developed for use in medical diagnostics. One such diagnostic, esophageal cancer is diagnosed currently through biopsy and subsequent pathology. The end goal of this research is to develop an optical-based technique to assist or replace biopsy. In this paper, we demonstrate an instrument that has the capability to optically diagnose cancer in laboratory mice. We have developed a real-time HSI system based on state-of-the-art liquid crystal tunable filter (LCTF) technology coupled to an endoscope. This unique HSI technology is being developed to obtain spatially resolved images of the slight differences in luminescent properties of normal versus tumorous tissues. In this report, an in-vivo mouse study is shown. A predictive measure of cancer for the mice studied is developed and shown. It is hoped that the results of this study will lead to advances in the optical diagnosis of esophageal cancer in humans.

  10. Spectroscopic imaging diagnostics for burning plasma experiments

    NASA Astrophysics Data System (ADS)

    Stutman, D.; Finkenthal, M.; Suliman, G.; Tritz, K.; Delgado-Aparicio, L.; Kaita, R.; Johnson, D.; Soukhanovskii, V.; May, M. J.

    2005-02-01

    Spectroscopic imaging of plasma emission profiles from a few electron volts to tens of kilo-electron volts enables basic diagnostics in present day tokamaks. For the more difficult burning plasma conditions, light extraction and detection techniques, as well as instrument designs need to be investigated. As an alternative to light extraction with reflective optics, we discuss normal incidence, transmissive-diffractive optics (e.g., transmission gratings), which might withstand plasma exposure with less degradation of optical properties. Metallic multilayer reflectors are also of interest for light extraction. Although a shift of the diffraction peak might occur, instrument designs that accommodate such shifts are possible. As imaging detectors we consider "optical" arrays based on conversion of the short-wavelength light into visible light followed by transport of the visible signal with hollow lightguides. The proposed approaches to light extraction and detection could enable radiation resistant diagnostics.

  11. [Imaging techniques in modern trauma diagnostics].

    PubMed

    Vogl, T J; Eichler, K; Marzi, I; Wutzler, S; Zacharowski, K; Frellessen, C

    2017-08-17

    Modern trauma room management requires interdisciplinary teamwork and synchronous communication between a team of anaesthesists, surgeons and radiologists. As the length of stay in the trauma room influences morbidity and mortality of a severely injured person, optimizing time is one of the main targets. With the direct involvement of modern imaging techniques the injuries caused by trauma should be detected within a very short period of time in order to enable a priority-orientated treatment. Radiology influences structure and process quality, management and development of trauma room algorithms regarding the use of imaging techniques. For the individual case interventional therapy methods can be added. Based on current data and on the Frankfurt experience the current diagnostic concepts of trauma diagnostics are presented.

  12. [Imaging techniques in modern trauma diagnostics].

    PubMed

    Vogl, T J; Eichler, K; Marzi, I; Wutzler, S; Zacharowski, K; Frellessen, C

    2017-05-01

    Modern trauma room management requires interdisciplinary teamwork and synchronous communication between a team of anaesthesists, surgeons and radiologists. As the length of stay in the trauma room influences morbidity and mortality of a severely injured person, optimizing time is one of the main targets. With the direct involvement of modern imaging techniques the injuries caused by trauma should be detected within a very short period of time in order to enable a priority-orientated treatment. Radiology influences structure and process quality, management and development of trauma room algorithms regarding the use of imaging techniques. For the individual case interventional therapy methods can be added. Based on current data and on the Frankfurt experience the current diagnostic concepts of trauma diagnostics are presented.

  13. [Imaging techniques in modern trauma diagnostics].

    PubMed

    Vogl, T J; Eichler, K; Marzi, I; Wutzler, S; Zacharowski, K; Frellessen, C

    2017-09-21

    Modern trauma room management requires interdisciplinary teamwork and synchronous communication between a team of anaesthesists, surgeons and radiologists. As the length of stay in the trauma room influences morbidity and mortality of a severely injured person, optimizing time is one of the main targets. With the direct involvement of modern imaging techniques the injuries caused by trauma should be detected within a very short period of time in order to enable a priority-orientated treatment. Radiology influences structure and process quality, management and development of trauma room algorithms regarding the use of imaging techniques. For the individual case interventional therapy methods can be added. Based on current data and on the Frankfurt experience the current diagnostic concepts of trauma diagnostics are presented.

  14. Optical imaging diagnostics for fusion plasmas

    SciTech Connect

    Allen, S.L.

    1988-04-01

    Imaging diagnostics are used for spatially/emdash/and temporally/emdash/resolved quantitative measurements of plasma properties such as the ionization particle source, particle and energy loss, and impurity radiation in magnetically confined fusion plasmas. Diagnostics equipped with multi-element solid-state detectors (often with image intensifiers) are well suited to the environment of large fusion machines with high magnetic field and x-ray and neutron fluxes. We have both conventional (16msframe) and highspeed video cameras to measure neutral deuterium H/sub ..cap alpha../ (6563 /angstrom/) emissions from fusion plasmas. Continuous high-speed measurements are made with video cameras operating at 0.1 to 0.5 msframe; gated cameras provide snapshots of 10 to 100 ..mu..s during each 16-ms video frame. Digital data acquisition and absolute intensity calibrations of the cameras enable detailed quantitative source measurements: these are extremely important in determining the particle balance of the plasma. In a liner confinement device, radial transport can be determined from the total particle balance. In a toroidal confinement device, the details of particle recycling can be determined. Optical imaging in other regions of the spectrum are also important, particularly for the diverter region of large tokamaks. Absolutely calibrated infrared cameras have been used to image to temperature changes in the wall and thereby determine the heat flux. Absolutely calibrated imaging ultraviolet spectrometers measure impurity concentrations; both spatial and spectral imaging instruments are employed. Representative data from each of these diagnostic systems will be presented. 16 refs., 8 figs.

  15. [Diagnostic imaging of peripheral renal vascular disorders].

    PubMed

    Hélénon, O; Correas, J M; Eiss, D; Khairoune, A; Merran, S

    2004-02-01

    Peripheral vascular disorders of the kidney involve the intrarenal branches of the renal vascular tree. It include occlusive (infarction and cortical necrosis) and non-occlusive vascular lesions (acquired arteriovenous fistulas, arteriovenous malformation, false aneurysms and microaneurysms). Initial diagnosis relies on color Doppler US and CT angiography. Angiography plays a therapeutic role. MR imaging provides useful diagnostic information on perfusion disorders especially in patients with renal insufficiency.

  16. Diagnostic imaging of lower urinary tract disease.

    PubMed

    Hecht, Silke

    2015-07-01

    Diagnostic imaging is routinely performed in small animals with lower urinary tract disease. Survey radiographs allow identification of radiopaque calculi, gas within the urinary tract, and lymph node or bone metastases. Cystography and urethrography remain useful in the evaluation of bladder or urethral rupture, abnormal communication with other organs, and lesions of the pelvic or penile urethra. Ultrasonography is the modality of choice for the diagnosis of most disorders. Computed tomography and magnetic resonance imaging are useful in evaluating the ureterovesical junction and intrapelvic lesions, monitoring the size of lesions, and evaluating lymph nodes and osseous structures for metastases. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Comparative Soot Diagnostics: 1 Year Report

    NASA Technical Reports Server (NTRS)

    Urban, David L.; Griffin, DeVon W.; Gard, Melissa Y.

    1998-01-01

    The motivation for the Comparative Soot Diagnostics (CSD) experiment lies in the broad practical importance of understanding combustion generated particulate. Depending upon the circumstances, particulate matter can affect the durability and performance of combustion equipment, can be a pollutant, can be used to detect fires and, in the form of soot, can be the dominant source of radiant energy from flames. Bright sooty fires are desirable for efficient energy extraction in furnaces and power equipment. In contrast, soot-enhanced radiation is undesirable in many propulsion systems (e.g. jet engines). The non-buoyant structure of most flames of practical interest (turbulent) makes understanding of soot processes in low gravity flames important to our ability to predict fire behavior on earth. These studies also have direct applications to fire safety in human-crew spacecraft, since smoke is the indicator used for automated detection in current spacecraft. In addition, recent tests conducted on MIR showed that a candle in a truly quiescent spacecraft environment can burn for tens of minutes. Consequently, this test and many earlier tests have demonstrated that fires in spacecraft can be considered a credible risk. In anticipation of this risk, NASA has included fire detectors on Skylab, smoke detectors on the Space Shuttle (STS), and smoke detectors in the design for the International Space Station (ISS). In the CSD experiment, these smoke detectors were tested using, quasi-steady, low-gravity, particulate generating materials. Samples of the particulate were also obtained from these low-gravity sources. This experiment provides the first such measurements aimed toward understanding of soot processes here on earth and for the testing and design of advanced spacecraft smoke detection systems. This paper describes the operation and preliminary results of the CSD experiment which was was conducted in the Middeck Glovebox Facility (MGBX) on USMP-3. The objectives of CSD

  18. Comparative Soot Diagnostics: 1 Year Report

    NASA Technical Reports Server (NTRS)

    Urban, David L.; Griffin, DeVon W.; Gard, Melissa Y.

    1998-01-01

    The motivation for the Comparative Soot Diagnostics (CSD) experiment lies in the broad practical importance of understanding combustion generated particulate. Depending upon the circumstances, particulate matter can affect the durability and performance of combustion equipment, can be a pollutant, can be used to detect fires and, in the form of soot, can be the dominant source of radiant energy from flames. Bright sooty fires are desirable for efficient energy extraction in furnaces and power equipment. In contrast, soot-enhanced radiation is undesirable in many propulsion systems (e.g. jet engines). The non-buoyant structure of most flames of practical interest (turbulent) makes understanding of soot processes in low gravity flames important to our ability to predict fire behavior on earth. These studies also have direct applications to fire safety in human-crew spacecraft, since smoke is the indicator used for automated detection in current spacecraft. In addition, recent tests conducted on MIR showed that a candle in a truly quiescent spacecraft environment can burn for tens of minutes. Consequently, this test and many earlier tests have demonstrated that fires in spacecraft can be considered a credible risk. In anticipation of this risk, NASA has included fire detectors on Skylab, smoke detectors on the Space Shuttle (STS), and smoke detectors in the design for the International Space Station (ISS). In the CSD experiment, these smoke detectors were tested using, quasi-steady, low-gravity, particulate generating materials. Samples of the particulate were also obtained from these low-gravity sources. This experiment provides the first such measurements aimed toward understanding of soot processes here on earth and for the testing and design of advanced spacecraft smoke detection systems. This paper describes the operation and preliminary results of the CSD experiment which was was conducted in the Middeck Glovebox Facility (MGBX) on USMP-3. The objectives of CSD

  19. Diagnostic imaging techniques in thyroid cancer

    SciTech Connect

    Friedman, M.; Toriumi, D.M.; Mafee, M.F.

    1988-02-01

    With the refinement of fine-needle aspiration, the specific applications of thyroid imaging techniques need to be reevaluated for efficiency and cost containment. No thyroid imaging test should be routinely obtained. Radionuclide scanning is most beneficial in evaluating the functional status of thyroid nodules when fine-needle aspiration is inadequate, the findings are benign, or when there is no discrete nodule that is palpated in an enlarged gland. When fine-needle aspiration is unavailable or unreliable, radionuclide scanning becomes a first-line diagnostic tool. Ultrasonography should be used primarily for identifying a solid component of a cystic nodule, determining the size of nodules on thyroxine suppression that are not easily palpable, or for performing guided fine-needle aspiration. Computerized tomography and magnetic resonance imaging both have a definite role in the evaluation of thyroid tumors. Magnetic resonance imaging is superior to computerized tomography for the evaluation of metastatic, retrotracheal, or mediastinal involvement of large thyroid tumors or goiters. Careful selection of the diagnostic techniques will ensure more accurate diagnosis and reduce unnecessary patient costs in the treatment of thyroid cancer.

  20. Diagnostic accuracy of cone-beam CT compared with panoramic images in predicting retromolar canal during extraction of impacted mandibular third molars

    PubMed Central

    Sisman, Yıldıray; Payveren-Arıkan, Mehtap; Sahman, Halil

    2015-01-01

    Objectives: The clinical significance of the existence of a retromolar canal and of its neurovascular content is not yet clear.The aim of the present study was to assess the visibility, diameter and course of the mandibular retromolarcanal (MRC) using cone beam computed tomography (CBCT) scan -had been taken for pre-operative radiographic evaluation of impacted mandibular third molars- compared to panoramic radiographs. Study Design: Subjects eligible for study enrollment were those who underwent preoperative CBCT scan for the extraction of impactedmandibular third molars were determined to be extremely close to the mandibular canal on panoramic radiographs. Radiographs were screened for the presence and course of retromolar canals, and linear measurements. Results: 947hemimandibles in 632 patients were examined.A total of 253 MRCs (144 left, 109 right) were detected with CBCT images (26.7%). Only 29 of these canals were also seen on the corresponding panoramic radiographs. Most MRCs had a vertical course (type VI, 28.46%), followed by slightly curved (type I, 26.09%). The visibility of the MRC on the OPGs, according to the increase in the diameter, was not statistically significant for both sides (p>.05).Statistically difference were found for the width at the point of origin from the mandibular canal (p: .037), the mean distance from the MRC to the second molar (p: .042) and height of MRC when compared the gender. Conclusions: The findings suggest that the MRC isn’t a rare anatomical structure. This study therefore clearly establishes the incidence and importance of the MRC. The detection of the presence of the MRC using CBCT may be crucial for extraction of mandibular third molars. Key words:Accessory innervation, cone beam computed tomography, mandibular anatomy, panoramic radiographs, retromolar canal, retromolar foramen. PMID:25475767

  1. Dose and diagnostic image quality in digital tomosynthesis imaging of facial bones in pediatrics

    NASA Astrophysics Data System (ADS)

    King, J. M.; Hickling, S.; Elbakri, I. A.; Reed, M.; Wrogemann, J.

    2011-03-01

    The purpose of this study was to evaluate the use of digital tomosynthesis (DT) for pediatric facial bone imaging. We compared the eye lens dose and diagnostic image quality of DT facial bone exams relative to digital radiography (DR) and computed tomography (CT), and investigated whether we could modify our current DT imaging protocol to reduce patient dose while maintaining sufficient diagnostic image quality. We measured the dose to the eye lens for all three modalities using high-sensitivity thermoluminescent dosimeters (TLDs) and an anthropomorphic skull phantom. To assess the diagnostic image quality of DT compared to the corresponding DR and CT images, we performed an observer study where the visibility of anatomical structures in the DT phantom images were rated on a four-point scale. We then acquired DT images at lower doses and had radiologists indicate whether the visibility of each structure was adequate for diagnostic purposes. For typical facial bone exams, we measured eye lens doses of 0.1-0.4 mGy for DR, 0.3-3.7 mGy for DT, and 26 mGy for CT. In general, facial bone structures were visualized better with DT then DR, and the majority of structures were visualized well enough to avoid the need for CT. DT imaging provides high quality diagnostic images of the facial bones while delivering significantly lower doses to the lens of the eye compared to CT. In addition, we found that by adjusting the imaging parameters, the DT effective dose can be reduced by up to 50% while maintaining sufficient image quality.

  2. Analysis of licensed South African diagnostic imaging equipment

    PubMed Central

    Kabongo, Joseph Mwamba; Nel, Susan; Pitcher, Richard Denys

    2015-01-01

    Introduction: Objective To conduct an analysis of all registered South Africa (SA) diagnostic radiology equipment, assess the number of equipment units per capita by imaging modality, and compare SA figures with published international data, in preparation for the introduction of national health insurance (NHI) in SA. Methods The SA Radiation Control Board's database of registered diagnostic radiology equipment was analysed by modality, province and healthcare sector. Access to services was reflected as number of units/million population, and compared with published international data. Results General X-ray units are the most equitably distributed and accessible resource (34.8/million). For fluoroscopy (6.6/million), mammography (4.96/million), computed tomography (5.0/million) and magnetic resonance imaging (2.9/million), there are at least 10-fold discrepancies between the least and best resourced provinces. Although SA's overall imaging capacity is well above that of other countries in sub-Saharan Africa, it is lower than that of all Organisation for Economic Co-operation and Development (OECD). While SA's radiological resources most closely approximate those of the United Kingdom, they are substantially lower than the UK. Conclusion SA access to radiological services is lower than that of any OECD country. For the NHI to achieve equitable access to diagnostic imaging for all citizens, SA will need a more homogeneous distribution of specialised radiological resources and customized imaging guidelines. PMID:26834910

  3. Diagnostic Performance of First-Pass Myocardial Perfusion Imaging without Stress with Computed Tomography (CT) Compared with Coronary CT Angiography Alone, with Fractional Flow Reserve as the Reference Standard.

    PubMed

    Osawa, Kazuhiro; Miyoshi, Toru; Miki, Takashi; Koyama, Yasushi; Sato, Shuhei; Kanazawa, Susumu; Ito, Hiroshi

    2016-01-01

    Coronary computed tomography angiography (CCTA) in combination with first-pass CT myocardial perfusion imaging (MPI) has a better diagnostic performance than CCTA alone, compared with invasive coronary angiography as the reference standard. The aim of this study was to investigate the additional diagnostic value of first-pass CT-MPI without stress for detecting hemodynamic significance of coronary stenosis, compared with invasive fractional flow reserve (FFR). We recruited 53 patients with suspected coronary artery disease undergoing both CCTA and first-pass CT-MPI without stress and invasive FFR, and 75 vessels were analyzed. We used the same raw data for CCTA and CT-MPI. First-pass CT-MPI was reconstructed by examining the diastolic signal densities as a bull's eye map. Invasive FFR <0.8 was considered as positive. On per-vessel analysis, the area under the receiver operating characteristic curve for CCTA plus first-pass CT-MPI and CCTA alone was 0.81 (0.73-0.90) and 0.70 (0.61-0.81), respectively (P = 0.036). CCTA plus first-pass CT-MPI without stress showed 0.73 sensitivity, 0.74 specificity, 0.53 positive predictive value, and 0.87 negative predictive value for detecting hemodynamically significant coronary stenosis. First-pass CT-MPI without stress correctly reclassified 38% of CCTA false-positive vessels as true negative. First-pass CT-MPI without stress combined with CCTA demonstrated excellent diagnostic accuracy, compared with invasive FFR as the reference standard. This technique could complement CCTA for diagnosis of coronary artery disease.

  4. Diagnostic imaging of the diabetic foot.

    PubMed

    Ranachowska, Celina; Lass, Piotr; Korzon-Burakowska, Anna; Dobosz, Marek

    2010-01-01

    Diabetic foot syndrome is a significant complication of diabetes. Diagnostic imaging is a crucial factor determining surgical decision and extent of surgical intervention. At present the gold standard is MRI scanning, whilst the role of bone scanning is decreasing, although in some cases it brings valuable information. In particular, in early stages of osteitis and Charcot neuro-osteoarthropathy, radionuclide imaging may be superior to MRI. Additionally, a significant contribution of inflammation-targeted scintigraphy should be noted. Probably the role of PET scanning will grow, although its high cost and low availability may be a limiting factor. In every case, vascular status should be determined, at least with Doppler ultrasound, with following conventional angiography or MR angiography.

  5. A survey of medical diagnostic imaging technologies

    SciTech Connect

    Heese, V.; Gmuer, N.; Thomlinson, W.

    1991-10-01

    The fields of medical imaging and medical imaging instrumentation are increasingly important. The state-of-the-art continues to advance at a very rapid pace. In fact, various medical imaging modalities are under development at the National Synchrotron Light Source (such as MECT and Transvenous Angiography.) It is important to understand how these techniques compare with today`s more conventional imaging modalities. The purpose of this report is to provide some basic information about the various medical imaging technologies currently in use and their potential developments as a basis for this comparison. This report is by no means an in-depth study of the physics and instrumentation of the various imaging modalities; instead, it is an attempt to provide an explanation of the physical bases of these techniques and their principal clinical and research capabilities.

  6. A survey of medical diagnostic imaging technologies

    SciTech Connect

    Heese, V.; Gmuer, N.; Thomlinson, W.

    1991-10-01

    The fields of medical imaging and medical imaging instrumentation are increasingly important. The state-of-the-art continues to advance at a very rapid pace. In fact, various medical imaging modalities are under development at the National Synchrotron Light Source (such as MECT and Transvenous Angiography.) It is important to understand how these techniques compare with today's more conventional imaging modalities. The purpose of this report is to provide some basic information about the various medical imaging technologies currently in use and their potential developments as a basis for this comparison. This report is by no means an in-depth study of the physics and instrumentation of the various imaging modalities; instead, it is an attempt to provide an explanation of the physical bases of these techniques and their principal clinical and research capabilities.

  7. Image standards in tissue-based diagnosis (diagnostic surgical pathology).

    PubMed

    Kayser, Klaus; Görtler, Jürgen; Goldmann, Torsten; Vollmer, Ekkehard; Hufnagl, Peter; Kayser, Gian

    2008-04-18

    Progress in automated image analysis, virtual microscopy, hospital information systems, and interdisciplinary data exchange require image standards to be applied in tissue-based diagnosis. To describe the theoretical background, practical experiences and comparable solutions in other medical fields to promote image standards applicable for diagnostic pathology. THEORY AND EXPERIENCES: Images used in tissue-based diagnosis present with pathology-specific characteristics. It seems appropriate to discuss their characteristics and potential standardization in relation to the levels of hierarchy in which they appear. All levels can be divided into legal, medical, and technological properties. Standards applied to the first level include regulations or aims to be fulfilled. In legal properties, they have to regulate features of privacy, image documentation, transmission, and presentation; in medical properties, features of disease-image combination, human-diagnostics, automated information extraction, archive retrieval and access; and in technological properties features of image acquisition, display, formats, transfer speed, safety, and system dynamics. The next lower second level has to implement the prescriptions of the upper one, i.e. describe how they are implemented. Legal aspects should demand secure encryption for privacy of all patient related data, image archives that include all images used for diagnostics for a period of 10 years at minimum, accurate annotations of dates and viewing, and precise hardware and software information. Medical aspects should demand standardized patients' files such as DICOM 3 or HL 7 including history and previous examinations, information of image display hardware and software, of image resolution and fields of view, of relation between sizes of biological objects and image sizes, and of access to archives and retrieval. Technological aspects should deal with image acquisition systems (resolution, colour temperature, focus

  8. Diagnostic imaging in mediastinal thyroid tumor

    SciTech Connect

    Shih, W.J.; Cho, S.R.; Purcell, M.; Tsung-Yao, H.; Domstad, P.A.; Liu, C.I.; DeLand, F.H.

    1984-12-01

    Various diagnostic imagings in nine patients with mediastinal goiters were presented. The clinical manifestations of these patients were various, from totally asymptomatic to severe dyspnea. Six of the nine patients underwent surgical intervention, three were follicular adenomas and three were nodular goiters. A chest radiograph (positive in seven out of nine patients) provided the most valuable initial localization of a goiter mass to the anterior, middle, or posterior compartment. Esophagograms (performed in four patients) showed compression of esophagus by the mediastinal mass. I-131 scintigraphy (performed in seven patients) was capable of detection of functional (in three patients) vs nonfunctional status of thyroid status (in four patients). Angiography (performed in five patients), characterized by anatomic continuity with cervical thyroid gland, calcifications, well-defined border of masses and/or contrast enhancement, offered important roles to direct a diagnosis of intrathoracic goiter. The computed tomography becomes increasingly important because all mediastinal goiters are not radioiodine avid.

  9. Diagnostic imaging for temporomandibular disorders and orofacial pain.

    PubMed

    Hunter, Allison; Kalathingal, Sajitha

    2013-07-01

    The focus of this article is diagnostic imaging used for the evaluation of temporomandibular disorders and orofacial pain patients. Imaging modalities discussed include conventional panoramic radiography, panoramic temporomandibular joint imaging mode, cone beam computed tomography, and magnetic resonance imaging. The imaging findings associated with common diseases of the temporomandibular joint are presented and indications for brain imaging are discussed. Advantages and disadvantages of each imaging modality are presented as well as illustrations of the various imaging techniques.

  10. The Evidence Value Matrix for Diagnostic Imaging.

    PubMed

    Seidel, David; Frank, Richard A; Schmidt, Sebastian

    2016-10-01

    Evidence and value are independent factors that together affect the adoption of diagnostic imaging. For example, noncoverage decisions by reimbursement authorities can be justified by a lack of evidence and/or value. To create transparency and a common understanding among various stakeholders, we have proposed a two-dimensional matrix that allows classification of imaging devices into three distinct categories based on the available evidence and value: "question marks" (low value demonstrated in studies of any evidence level), "candidates" (high value demonstrated in retrospective case-control studies and smaller case series), and "stars" (high value demonstrated in large prospective cohort studies or, preferably, randomized controlled trials). We use several examples to illustrate the application of our matrix. A major benefit of the matrix includes the development of specific strategies for evidence and value generation. High-evidence/low-value studies are expensive and unlikely to convince decision makers, given the uncertainty of the impact on patient management and outcomes. Developing question marks into candidates first and then into stars will often be quicker and less expensive ("success sequence"). Only this more sophisticated and objective approach can justify the additional funding necessary to generate the evidence base to inform reimbursement by payers and adoption by providers.

  11. Diagnostic imaging in patients with retinitis pigmentosa.

    PubMed

    Mitamura, Yoshinori; Mitamura-Aizawa, Sayaka; Nagasawa, Toshihiko; Katome, Takashi; Eguchi, Hiroshi; Naito, Takeshi

    2012-01-01

    Retinitis pigmentosa (RP) is a progressive inherited retinal disease, and patients with RP have reduced visual function caused by a degeneration of the photoreceptors and retinal pigment epithelium (RPE). At the end stage of RP, the degeneration of the photoreceptors in the fovea reduces central vision, and RP is one of the main causes of acquired blindness in developed countries. Therefore, morphological and functional assessments of the photoreceptors in the macula area can be useful in estimating the residual retinal function in RP patients. Optical coherence tomography (OCT) is a well-established method of examining the retinal architecture in situ. The photoreceptor inner/outer segment (IS/OS) junction is observed as a distinct, highly reflective line by OCT. The presence of the IS/OS junction in the OCT images is essential for normal visual function. Fundus autofluorescence (FAF) results from the accumulation of lipofuscin in the RPE cells and has been used to investigate RPE and retinal function. More than one-half of RP patients have an abnormally high density parafoveal FAF ring (AF ring). The AF ring represents the border between functional and dysfunctional retina. In this review, we shall summarize recent progress on diagnostic imaging in eyes with RP.

  12. Diagnostic Imaging Guidelines Implementation Study for Spinal Disorders

    PubMed Central

    Bussières, André E.; Laurencelle, Louis; Peterson, Cynthia

    2010-01-01

    Purpose: Implementation strategies of imaging guidelines can assist in reducing the number of radiographic examinations. This study aimed to compare the perceived need for diagnostic imaging before and after an educational intervention strategy. Methods: One hundred sixty Swiss chiropractors attending a conference were randomized to either receive a radiology workshop, reviewing appropriate indications for diagnostic imaging for adult spine disorders (n = 80), or be in a control group (CG). One group of 40 individuals dropped out from the CG due to logistic reasons. Participants in the intervention group were randomly assigned to three subgroups to evaluate the effect of an online reminder at midpoint. All participants underwent a pretest and a final test at 14–16 weeks. A posttest was administered to two subgroups at 8–10 weeks. Results: There was no difference between baseline scores, and overall scores for the pretest and the final tests for all four groups were not significantly different. However, the subgroup provided with access to a reminder performed significantly better than the subgroup with whom they were compared (F = 4.486; df = 1 and 30; p = .043). Guideline adherence was 50.5% (95% CI, 39.1–61.8) for the intervention group and 43.7% (95% CI, 23.7–63.6) for the CG at baseline. Adherence at follow-up was lower, but mean group differences remained insignificant. Conclusions: Online access to specific recommendations while making a clinical decision may favorably influence the intention to either order or not order imaging studies. However, a didactic presentation alone did not appear to change the perception for the need of diagnostic imaging studies. PMID:20480010

  13. Diagnostic Imaging and Problems of Schizencephaly

    PubMed Central

    Stopa, Joanna; Kucharska-Miąsik, Iwona; Dziurzyńska-Białek, Ewa; Kostkiewicz, Agnieszka; Solińska, Anna; Zając-Mnich, Monika; Guz, Wiesław; Samojedny, Antoni

    2014-01-01

    Summary Background Schizencephaly is a rare developmental malformation of the central nervous system associated with cell migration disturbances. Schizencephaly can be uni- or bilateral and is divided into two morphological types. The cleft is defined as type I (“closed lips”) if there are fused clefts in cerebral mantle. In type II (“open lips”) the clefts are separated and filled with cerebrospinal fluid connecting lateral ventricle with the subarachnoid space. Material/Methods We retrospectively analysed data of patients hospitalized in the Clinical Pediatric Neurology Department of Provincial Hospital No. 2 in Rzeszow between 1998–2011. Clinical data and imaging exams were analysed in the group of children with confirmed schizencephaly. Results Schizencephaly was recognized in 32 children. Diagnosis was made in children at the ages between 2 weeks and 15 years – the majority of older children were born before the year 2000. Diagnostic imaging, most often magnetic resonance imaging, was performed in all of the children. In most cases coexistence of other CNS malformations was discovered. In only one patient there were no neurological symptoms, most of the children presented different developmental disorders and neurological symptoms – most often cerebral palsy and epilepsy. In the group of children with bilateral and type II schizencephaly certain symptoms occurred more often. Conclusions Schizencephaly is a rare central nervous system developmental disorder, which is very often associated with other severe brain malformations and in most of the cases subsequent multiple neurological symptoms. The method of choice in diagnosis of schizencephaly is magnetic resonance, which shows the degree and type of cleft, coexisting abnormalities and allows differential diagnosis. With the increased availability of this method it is possible to recognize schizencephaly more often and earlier. PMID:25473439

  14. A multispectral imaging approach for diagnostics of skin pathologies

    NASA Astrophysics Data System (ADS)

    Lihacova, Ilze; Derjabo, Aleksandrs; Spigulis, Janis

    2013-06-01

    Noninvasive multispectral imaging method was applied for different skin pathology such as nevus, basal cell carcinoma, and melanoma diagnostics. Developed melanoma diagnostic parameter, using three spectral bands (540 nm, 650 nm and 950 nm), was calculated for nevus, melanoma and basal cell carcinoma. Simple multispectral diagnostic device was established and applied for skin assessment. Development and application of multispectral diagnostics method described further in this article.

  15. Diagnostic performance of cardiac imaging methods to diagnose ischaemia-causing coronary artery disease when directly compared with fractional flow reserve as a reference standard: a meta-analysis

    PubMed Central

    Danad, Ibrahim; Szymonifka, Jackie; Twisk, Jos W.R.; Norgaard, Bjarne L.; Zarins, Christopher K.; Knaapen, Paul

    2017-01-01

    Aims The aim of this study was to determine the diagnostic performance of single-photon emission computed tomography (SPECT), stress echocardiography (SE), invasive coronary angiography (ICA), coronary computed tomography angiography (CCTA), fractional flow reserve (FFR) derived from CCTA (FFRCT), and cardiac magnetic resonance (MRI) imaging when directly compared with an FFR reference standard. Method and results PubMed and Web of Knowledge were searched for investigations published between 1 January 2002 and 28 February 2015. Studies performing FFR in at least 75% of coronary vessels for the diagnosis of ischaemic coronary artery disease (CAD) were included. Twenty-three articles reporting on 3788 patients and 5323 vessels were identified. Meta-analysis was performed for pooled sensitivity, specificity, likelihood ratios (LR), diagnostic odds ratio, and summary receiver operating characteristic curves. In contrast to ICA, CCTA, and FFRCT reports, studies evaluating SPECT, SE, and MRI were largely retrospective, single-centre and with generally smaller study samples. On a per-patient basis, the sensitivity of CCTA (90%, 95% CI: 86–93), FFRCT (90%, 95% CI: 85–93), and MRI (90%, 95% CI: 75–97) were higher than for SPECT (70%, 95% CI: 59–80), SE (77%, 95% CI: 61–88), and ICA (69%, 95% CI: 65–75). The highest and lowest per-patient specificity was observed for MRI (94%, 95% CI: 79–99) and for CCTA (39%, 95% CI: 34–44), respectively. Similar specificities were noted for SPECT (78%, 95% CI: 68–87), SE (75%, 95% CI: 63–85), FFRCT (71%, 95% CI: 65–75%), and ICA (67%, 95% CI: 63–71). On a per-vessel basis, the highest sensitivity was for CCTA (pooled sensitivity, 91%: 88–93), MRI (91%: 84–95), and FFRCT (83%, 78–87), with lower sensitivities for ICA (71%, 69–74), and SPECT (57%: 49–64). Per-vessel specificity was highest for MRI (85%, 79–89), FFRCT (78%: 78–81), and SPECT (75%: 69–80), whereas ICA (66%: 64–68) and CCTA (58%: 55

  16. Sedation for emergent diagnostic imaging studies in pediatric patients.

    PubMed

    Rutman, Maia S

    2009-06-01

    To review and summarize current literature regarding sedation for imaging studies in pediatric patients in the Emergency Department and acute care setting. Multiple guidelines about preparation, monitoring, and appropriate training of personnel administering pediatric sedation have been published. Recommendations for fasting prior to sedation remain in flux. Agents such as chloral hydrate, barbiturates, and benzodiazepines that have been used for pediatric sedation for many years continue to be studied. These agents are compared with newer agents such as etomidate, propofol, and dexmedetomidine. Although avoiding sedation for diagnostic imaging studies is optimal, there are multiple agents with reasonable safety profiles that can be utilized by personnel trained in pediatric airway management in order to obtain adequate emergent imaging studies.

  17. Fluorescence diagnostic imaging in patients with acne.

    PubMed

    Dobrev, Hristo

    2010-12-01

    Orange-red fluorescence in the follicle openings, induced by ultraviolet A light, originates from porphyrins, the metabolic products of Propionibacteria acnes. To investigate the relationship of orange-red follicular fluorescence with the severity of acne and the amount of sebum secretion. Twenty-five volunteers were included. The severity of acne was rated on a 4-point scale. The casual sebum level was measured using a Sebumeter and the follicular fluorescence was determined using the camera Visiopor. Casual sebum level and the intensity of fluorescence (percentage of the area and number of orange-red spots) were higher at the T zone than at the U zone in all patients regardless of their skin type. Sebum amount and area of fluorescence spots were significantly negative in correlation with the clinical grade of acne. There was a significant positive correlation between the orange-red fluorescence and the casual sebum level. The orange-red fluorescence showed stronger correlation with the presence of non-inflammatory acne lesions (comedones) and high sebum amount than the presence of inflammatory acne lesions (pustules) and low sebum amount. The fluorescence diagnostic imaging could be useful in the objective evaluation and monitoring of treatment efficacy in subjects with acne-prone skin and patients with acne. © 2010 John Wiley & Sons A/S.

  18. Diagnostic imaging in pediatric polytrauma management.

    PubMed

    Miele, Vittorio; Di Giampietro, Ilenia; Ianniello, Stefania; Pinto, Fabio; Trinci, Margherita

    2015-01-01

    Trauma is the cause of over 45% of deaths in children aged 1 to 14 years. Since multiple injuries are common among children, the emergency physician has to assess all the organs of a high-energy injured child, independent of mechanism of the trauma. Even if the principles of polytrauma management are identical both in children and in adults, the optimal pediatric patient care requires a specific understanding of some important anatomical, physiological, and psychological differences that play a significant role in the assessment and management of a pediatric patient. Emergency Radiology already plays a crucial role in the diagnostic process of a polytraumatized child according to the primary survey, through the use of multiple imaging modalities. Radiological and Ultrasound examinations play a basic role in the hemodynamically unstable patients. In the hemodynamically stable patients whole-body CT scanning is the most immediate radiological procedure that allows the examination of all the body parts of a polytraumatized child, reducing the number of minor injuries that might otherwise be neglected.

  19. Perfluorocarbon Compounds: Applications In Diagnostic Imaging

    NASA Astrophysics Data System (ADS)

    Mattrey, Robert F.

    1986-06-01

    Perfluorocarbon compounds (PFC's), well known in industry and of late as synthetic oxygen carriers, have a wide range of significant applications in diagnostic imaging. Their enhancement effect is detectable by ultrasound and magnetic resonance and if radiopaque, such as perfluoroctylbromide (PFOB), by standard radiography and computed tomography (CT). We have utilized PFOB as a CT contrast agent to enhance the blood pool, and as both a CT and an ultrasound contrast agent to enhance the liver, spleen, abscesses, infarctions, and tumors or any tissue where inflammatory cells can be found. PFC's, except for the echogenic enhancement of the vascular space on their first pass to the lung, do not enhance the blood pool on ultrasound. Otherwise, ultrasound applications are similar to those observed for CT. Fluosol, which was available for human trials, is not radiopaque and therefore served as an ultrasound contrast agent. In a preliminary clinical trial, Fluosol produced tumor enhancement in man at 1.6g/kg allowing the visualization of previously missed lesions and liver and spleen enhancement at 2.4g/kg allowing the visualization of previously missed non-enhancing lesions. Perfluorocarbon toxicity seems to be related to the constituents of the emulsion rather than the perfluorocarbon itself. Improvements in the emulsifier and emulsification technology has yielded stable emulsions at high concentrations and low toxicity.

  20. Diagnostic time in digital pathology: A comparative study on 400 cases.

    PubMed

    Vodovnik, Aleksandar

    2016-01-01

    Numerous validation studies in digital pathology confirmed its value as a diagnostic tool. However, a longer time to diagnosis than traditional microscopy has been seen as a significant barrier to the routine use of digital pathology. As a part of our validation study, we compared a digital and microscopic diagnostic time in the routine diagnostic setting. One senior staff pathologist reported 400 consecutive cases in histology, nongynecological, and fine needle aspiration cytology (20 sessions, 20 cases/session), over 4 weeks. Complex, difficult, and rare cases were excluded from the study to reduce the bias. A primary diagnosis was digital, followed by traditional microscopy, 6 months later, with only request forms available for both. Microscopic slides were scanned at ×20, digital images accessed through the fully integrated laboratory information management system (LIMS) and viewed in the image viewer on double 23" displays. A median broadband speed was 299 Mbps. A diagnostic time was measured from the point slides were made available to the point diagnosis was made or additional investigations were deemed necessary, recorded independently in minutes/session and compared. A digital diagnostic time was 1841 and microscopic 1956 min; digital being shorter than microscopic in 13 sessions. Four sessions with shorter microscopic diagnostic time included more cases requiring extensive use of magnifications over ×20. Diagnostic time was similar in three sessions. A diagnostic time in digital pathology can be shorter than traditional microscopy in the routine diagnostic setting, with adequate and stable network speeds, fully integrated LIMS and double displays as default parameters. This also related to better ergonomics, larger viewing field, and absence of physical slide handling, with effects on both diagnostic and nondiagnostic time. Differences with previous studies included a design, image size, number of cases, specimen type, network speed, and participant

  1. 3D ultrasound imaging for prosthesis fabrication and diagnostic imaging

    SciTech Connect

    Morimoto, A.K.; Bow, W.J.; Strong, D.S.

    1995-06-01

    The fabrication of a prosthetic socket for a below-the-knee amputee requires knowledge of the underlying bone structure in order to provide pressure relief for sensitive areas and support for load bearing areas. The goal is to enable the residual limb to bear pressure with greater ease and utility. Conventional methods of prosthesis fabrication are based on limited knowledge about the patient`s underlying bone structure. A 3D ultrasound imaging system was developed at Sandia National Laboratories. The imaging system provides information about the location of the bones in the residual limb along with the shape of the skin surface. Computer assisted design (CAD) software can use this data to design prosthetic sockets for amputees. Ultrasound was selected as the imaging modality. A computer model was developed to analyze the effect of the various scanning parameters and to assist in the design of the overall system. The 3D ultrasound imaging system combines off-the-shelf technology for image capturing, custom hardware, and control and image processing software to generate two types of image data -- volumetric and planar. Both volumetric and planar images reveal definition of skin and bone geometry with planar images providing details on muscle fascial planes, muscle/fat interfaces, and blood vessel definition. The 3D ultrasound imaging system was tested on 9 unilateral below-the- knee amputees. Image data was acquired from both the sound limb and the residual limb. The imaging system was operated in both volumetric and planar formats. An x-ray CT (Computed Tomography) scan was performed on each amputee for comparison. Results of the test indicate beneficial use of ultrasound to generate databases for fabrication of prostheses at a lower cost and with better initial fit as compared to manually fabricated prostheses.

  2. Modifications to the synthetic aperture microwave imaging diagnostic

    SciTech Connect

    Brunner, K. J.; Chorley, J. C.; Dipper, N. A.; Naylor, G.; Sharples, R. M.; Taylor, G.; Thomas, D. A.; Vann, R. G. L.

    2016-09-02

    The synthetic aperture microwave imaging diagnostic has been operating on the MAST experiment since 2011. It has provided the first 2D images of B-X-O mode conversion windows and showed the feasibility of conducting 2D Doppler back-scattering experiments. The diagnostic heavily relies on field programmable gate arrays to conduct its work. Recent successes and newly gained experience with the diagnostic have led us to modify it. The enhancements will enable pitch angle profile measurements, O and X mode separation, and the continuous acquisition of 2D DBS data. Finally, the diagnostic has also been installed on the NSTX-U and is acquiring data since May 2016.

  3. Modifications to the synthetic aperture microwave imaging diagnostic

    NASA Astrophysics Data System (ADS)

    Brunner, K. J.; Chorley, J. C.; Dipper, N. A.; Naylor, G.; Sharples, R. M.; Taylor, G.; Thomas, D. A.; Vann, R. G. L.

    2016-11-01

    The synthetic aperture microwave imaging diagnostic has been operating on the MAST experiment since 2011. It has provided the first 2D images of B-X-O mode conversion windows and showed the feasibility of conducting 2D Doppler back-scattering experiments. The diagnostic heavily relies on field programmable gate arrays to conduct its work. Recent successes and newly gained experience with the diagnostic have led us to modify it. The enhancements will enable pitch angle profile measurements, O and X mode separation, and the continuous acquisition of 2D DBS data. The diagnostic has also been installed on the NSTX-U and is acquiring data since May 2016.

  4. Modifications to the synthetic aperture microwave imaging diagnostic

    SciTech Connect

    Brunner, K. J.; Chorley, J. C.; Dipper, N. A.; Naylor, G.; Sharples, R. M.; Taylor, G.; Thomas, D. A.; Vann, R. G. L.

    2016-09-02

    The synthetic aperture microwave imaging diagnostic has been operating on the MAST experiment since 2011. It has provided the first 2D images of B-X-O mode conversion windows and showed the feasibility of conducting 2D Doppler back-scattering experiments. The diagnostic heavily relies on field programmable gate arrays to conduct its work. Recent successes and newly gained experience with the diagnostic have led us to modify it. The enhancements will enable pitch angle profile measurements, O and X mode separation, and the continuous acquisition of 2D DBS data. Finally, the diagnostic has also been installed on the NSTX-U and is acquiring data since May 2016.

  5. Magnetic resonance imaging-targeted biopsy may enhance the diagnostic accuracy of significant prostate cancer detection compared to standard transrectal ultrasound-guided biopsy: a systematic review and meta-analysis.

    PubMed

    Schoots, Ivo G; Roobol, Monique J; Nieboer, Daan; Bangma, Chris H; Steyerberg, Ewout W; Hunink, M G Myriam

    2015-09-01

    Multiparametric magnetic resonance imaging (MRI) of the prostate may improve the diagnostic accuracy of prostate cancer detection in MRI-targeted biopsy (MRI-TBx) in comparison to transrectal ultrasound-guided biopsy (TRUS-Bx). Systematic review and meta-analysis of evidence regarding the diagnostic benefits of MRI-TBx versus TRUS-Bx in detection of overall prostate cancer (primary objective) and significant/insignificant prostate cancer (secondary objective). A systematic review of Embase, Medline, Web of Science, Scopus, PubMed, Cinahl, and the Cochrane library was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Identified reports were critically appraised according to the Quality Assessment of Diagnostic Accuracy Studies criteria. Only men with a positive MRI were included. The reports we included (16 studies) used both MRI-TBx and TRUS-Bx for prostate cancer detection. A cumulative total of 1926 men with positive MRI were included, with prostate cancer prevalence of 59%. MRI-TBx and TRUS-Bx did not significantly differ in overall prostate cancer detection (sensitivity 0.85, 95% confidence interval [CI] 0.80-0.89, and 0.81, 95% CI 0.70-0.88, respectively). MRI-TBx had a higher rate of detection of significant prostate cancer compared to TRUS-Bx (sensitivity 0.91, 95% CI 0.87-0.94 vs 0.76, 95% CI 0.64-0.84) and a lower rate of detection of insignificant prostate cancer (sensitivity 0.44, 95% CI 0.26-0.64 vs 0.83, 95% confidence interval 0.77-0.87). Subgroup analysis revealed an improvement in significant prostate cancer detection by MRI-TBx in men with previous negative biopsy, rather than in men with initial biopsy (relative sensitivity 1.54, 95% CI 1.05-2.57 vs 1.10, 95% CI 1.00-1.22). Because of underlying methodological flaws of MRI-TBx, the comparison of MRI-TBx and TRUS-Bx needs to be regarded with caution. In men with clinical suspicion of prostate cancer and a subsequent positive MRI, MRI-TBx and

  6. Diagnosis of bone metastasis: recent comparative studies of imaging modalities.

    PubMed

    Talbot, J N; Paycha, F; Balogova, S

    2011-08-01

    Various imaging modalities are currently available to diagnose bone metastasis. The two main anatomical modalities are computed tomography (CT) and magnetic resonance imaging (MRI), with many variants proposed for the MRI procedure, including diffusion-weighted imaging. The two main functional modalities are scintigraphy and PET, also with many variants in the radiopharmaceutical, from the "all purpose" 99mTc labelled bisphosphonates to very selective radiopharmaceuticals for rare neoplasia. The diagnostic strategy will become more and more individually tailored according to the patient's clinical and biological data (primary cancer type, phase of the evolution, markers of aggressiveness, serum levels of biological tracers of bone metabolism, circulating or disseminating tumour cells …). If imaging is indicated, the diagnostic strategy will also depend on the availability and the diagnostic performance of the imaging modalities. Assessment of diagnostic performance requires comparative studies, performed with an adequate methodology. The main methodological weaknesses encountered in studies intending to compare imaging modalities for diagnosing bone metastasis are summarised. Comparative studies have been reviewed, which address the initial diagnosis of skeletal metastases in solid tumours except primary bone cancers. The results of more than 140 such comparative studies are then summarised and briefly commented, according to the type of the primary cancer, and according to the compared imaging modalities.

  7. Diagnostic imaging of acute pulmonary embolism.

    PubMed

    Christiansen, F

    1997-01-01

    The common strategy of combining clinical information, lung scintigraphy and pulmonary angiography in the diagnosis of acute pulmonary embolism (PE), has many limitations in clinical use. The major causes are that pulmonary angiography and lung scintigraphy are not universally available, and that pulmonary angiography is very expensive. The purpose of this thesis was to analyse different aspects of validity in regard to lung scintigraphy, pulmonary angiography, spiral CT, and ultrasound of the legs, with the subsequent intention of discussing new diagnostic strategies. Observer variations in lung scintigraphy interpretation when applying the PIOPED criteria were tested in 2 studies with 2 and 3 observers respectively and expressed as kappa values. The ability to improve agreement in lung scintigraphy interpretation was tested by training 2 observers from different hospitals. The impact of 3 observers' variations in lung scintigraphy interpretation when compared to pulmonary angiography, was tested by comparing the ROC areas of the observers. The value of combining subjectively derived numerical probabilities and the PIOPED categorical probabilities in lung scintigraphy reporting was compared to using the PIOPED categorization only, and this was tested by comparing ROC areas. The sensitivity and specificity of detecting an embolic source in the deep veins of the legs by ultrasound as a sign of PE when lung scintigraphy is inconclusive, was tested by comparison with pulmonary angiography. The sensitivity and specificity of spiral CT, compared to pulmonary angiography, was tested by comparison to pulmonary angiography. The inter- and intra-observer kappa values were in the range of moderate and fair. It was not possible to achieve better kappa values after training. Although observer variations were substantial, the accuracy did not differ significantly between the 3 observers. Incoorporating subjectively derived probabilities into lung scan reporting could not reduce

  8. Technology Advances in Support of Fusion Plasma Imaging Diagnostics

    NASA Astrophysics Data System (ADS)

    Jiang, Qi; Lai, Jiali; Hu, Fengqi; Li, Maijou; Chang, Yu-Ting; Domier, Calvin; Luhmann, Neville, Jr.

    2012-10-01

    Innovative technologies are under investigation in key areas to enhance the performance of microwave and millimeter-wave fusion plasma imaging diagnostics. Novel antenna and mixer configurations are being developed at increasingly higher frequencies, to facilitate the use of electron cyclotron emission imaging (ECEI) on high field (> 2.6 T) plasma devices. Low noise preamplifier-based imaging antenna arrays are being developed to increase the sensitivity and dynamic range of microwave imaging reflectometry (MIR) diagnostics for the localized measurement of turbulent density fluctuations. High power multi-frequency sources, fabricated using advanced CMOS technology, offer the promise of allowing MIR-based diagnostic instruments to image these density fluctuations in 2-D over an extended plasma volume in high performance tokamak plasmas. Details regarding each of these diagnostic development areas will be presented.

  9. Diagnostic Imaging of Hepatocellular Carcinoma - A Pictorial Essay

    PubMed Central

    Nowicki, Tomasz K.; Markiet, Karolina; Szurowska, Edyta

    2017-01-01

    Hepatocellular carcinoma (HCC) is the most common primary liver cancer, which develops mostly in the setting of chronic liver disease. European Association for the Study of the Liver (EASL) and European Organization for Research and Treatment of Cancer (EORTC) prepared guidelines for screening, follow-up and diagnosis of HCC to facilitate decision making and optimize both diagnostic and therapeutic protocols. The review briefly describes etiology, epidemiology and histopathology of HCC and presents EASL-EORTC guidelines for surveillance and diagnosis of HCC. Target population and screening algorithm is presented in the surveillance section. Ultrasound imaging of HCC and the role of contrast enhanced ultrasound are described as well as the value of laboratory tests in screening. Further, radiological features of HCC in multiphase CT and dynamic contrast enhanced MRI and diagnostic criteria are presented. Additionally, the advantages of advanced techniques in MRI such as diffusion weighed imaging and the use of hepatocyte-specific contrast agents are discussed. Lastly, the EASL-EORTC guidelines are compared with the guidelines of the American Association for the Study of Liver Diseases and the Japan Society of Hepatology. Also LI-RADS and the Barcelona Clinic Liver Cancer classification are mentioned. In the near future, due to the ongoing advances in imaging a revision of the guidelines may be expected. PMID:28553196

  10. Comparative study of bowtie and patient scatter in diagnostic CT

    NASA Astrophysics Data System (ADS)

    Prakash, Prakhar; Boudry, John M.

    2017-03-01

    A fast, GPU accelerated Monte Carlo engine for simulating relevant photon interaction processes over the diagnostic energy range in third-generation CT systems was developed to study the relative contributions of bowtie and object scatter to the total scatter reaching an imaging detector. Primary and scattered projections for an elliptical water phantom (major axis set to 300mm) with muscle and fat inserts were simulated for a typical diagnostic CT system as a function of anti-scatter grid (ASG) configurations. The ASG design space explored grid orientation, i.e. septa either a) parallel or b) parallel and perpendicular to the axis of rotation, as well as septa height. The septa material was Tungsten. The resulting projections were reconstructed and the scatter induced image degradation was quantified using common CT image metrics (such as Hounsfield Unit (HU) inaccuracy and loss in contrast), along with a qualitative review of image artifacts. Results indicate object scatter dominates total scatter in the detector channels under the shadow of the imaged object with the bowtie scatter fraction progressively increasing towards the edges of the object projection. Object scatter was shown to be the driving factor behind HU inaccuracy and contrast reduction in the simulated images while shading artifacts and elevated loss in HU accuracy at the object boundary were largely attributed to bowtie scatter. Because the impact of bowtie scatter could not be sufficiently mitigated with a large grid ratio ASG, algorithmic correction may be necessary to further mitigate these artifacts.

  11. Diagnostic Accuracy of Gd-EOB-DTPA for Detection Hepatocellular Carcinoma (HCC): A Comparative Study with Dynamic Contrast Enhanced Magnetic Resonance Imaging (MRI) and Dynamic Contrast Enhanced Computed Tomography (CT)

    PubMed Central

    Imbriaco, Massimo; De Luca, Serena; Coppola, Milena; Fusari, Mario; Klain, Michele; Puglia, Marta; Mainenti, Pierpaolo; Liuzzi, Raffaele; Maurea, Simone

    2017-01-01

    Summary Background To compare the diagnostic accuracy of hepato-biliary (HB) phase with gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic acid (Gd-EOB-DTPA) with dynamic contrast-enhanced MR imaging (DCEMRI) and contrast-enhanced CT (DCECT) for hepatocellular carcinoma (HCC) detection. Material/Methods 73 patients underwent DCECT and Gd-EOB-DTPA-3T-MR. Lesions were classified using a five-point confidence scale. Reference standard was a combination of pathological evidence and tumor growth at follow-up CT/MR at 12 months. Receiver Operating Characteristic (ROC) curves were obtained. Results A total of 125 lesions were confirmed in 73 patients. As many as 74 were HCCs and 51 were benign. Area under the curve (AUC) was 0.984 for DCEMRI+HB phase vs. 0.934 for DCEMRI (p<0.68) and 0.852 for DCECT (p<0.001). For lesions >20 mm (n.40), AUC was 0.984 for DCEMRI+HB phase, 0.999 for DCEMRI, and 0.913 for DCECT, (p=n.s.). For lesions <20 mm (n.85) AUC was 0.982 for DCEMRI+HB phase vs. 0.910 for DCEMRI (p<0.01) and 0.828 for DCECT (p<0.001). Conclusions The addition of HB phase to DCEMRI provides an incremental accuracy of 4.5% compared to DCEMRI and DCECT for HCC detection. The accuracy of Gd-EOB-DTPA-3T-MR significantly improves for lesions <20 mm. No significant improvement is observed for lesions >20 mm and patients with Child-Pugh class B or C. PMID:28217239

  12. Planning and developing a diagnostic imaging center.

    PubMed

    Meehan, Margaret J; Whelton, Dianne G

    2004-12-01

    The convergence of an aging population, new technology, and an increasing number of clinical applications and reimbursements has created a favorable environment for ambulatory imaging centers. From a patient's perspective, features such as easy access, parking, appointment availability, and a setting that caters to outpatients are attractive compared with the hospital environment. Before embarking on a venture, the execution of a careful, thorough planning process, from the inception of the idea to the opening, is vital to success. This article provides guidance on the process by discussing the process of determining whether a project is feasible; developing a business plan that will measure potential success; locating, financing, and planning space; contractor selection and project management; and planning operations.

  13. Overuse of Diagnostic Imaging for Work-Related Injuries.

    PubMed

    Clendenin, Brianna Rebecca; Conlon, Helen Acree; Burns, Candace

    2017-02-01

    Overuse of health care in the United States is a growing concern. This article addresses the use of diagnostic imaging for work-related injuries. Diagnostic imaging drives substantial cost for increases in workers' compensation. Despite guidelines published by the American College of Radiology and the American College of Occupational Medicine and the Official Disability Guidelines, practitioners are prematurely ordering imaging sooner than recommended. Workers are exposed to unnecessary radiation and are incurring increasing costs without evidence of better outcomes. Practitioners caring for workers and submitting workers' compensation claims should adhere to official guidelines, using their professional judgment to consider financial impact and health outcomes of diagnostic imaging including computed tomography, magnetic resonance imaging, nuclear medicine imaging, radiography, and ultrasound.

  14. Acoustic Waves in Medical Imaging and Diagnostics

    PubMed Central

    Sarvazyan, Armen P.; Urban, Matthew W.; Greenleaf, James F.

    2013-01-01

    Up until about two decades ago acoustic imaging and ultrasound imaging were synonymous. The term “ultrasonography,” or its abbreviated version “sonography” meant an imaging modality based on the use of ultrasonic compressional bulk waves. Since the 1990s numerous acoustic imaging modalities started to emerge based on the use of a different mode of acoustic wave: shear waves. It was demonstrated that imaging with these waves can provide very useful and very different information about the biological tissue being examined. We will discuss physical basis for the differences between these two basic modes of acoustic waves used in medical imaging and analyze the advantages associated with shear acoustic imaging. A comprehensive analysis of the range of acoustic wavelengths, velocities, and frequencies that have been used in different imaging applications will be presented. We will discuss the potential for future shear wave imaging applications. PMID:23643056

  15. Acoustic waves in medical imaging and diagnostics.

    PubMed

    Sarvazyan, Armen P; Urban, Matthew W; Greenleaf, James F

    2013-07-01

    Up until about two decades ago acoustic imaging and ultrasound imaging were synonymous. The term ultrasonography, or its abbreviated version sonography, meant an imaging modality based on the use of ultrasonic compressional bulk waves. Beginning in the 1990s, there started to emerge numerous acoustic imaging modalities based on the use of a different mode of acoustic wave: shear waves. Imaging with these waves was shown to provide very useful and very different information about the biological tissue being examined. We discuss the physical basis for the differences between these two basic modes of acoustic waves used in medical imaging and analyze the advantages associated with shear acoustic imaging. A comprehensive analysis of the range of acoustic wavelengths, velocities and frequencies that have been used in different imaging applications is presented. We discuss the potential for future shear wave imaging applications. Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  16. A dynamic infrared imaging-based diagnostic process for breast cancer.

    PubMed

    Joro, R; Lääperi, A-L; Dastidar, P; Järvenpää, R; Kuukasjärvi, T; Toivonen, T; Saaristo, R; Soimakallio, S

    2009-10-01

    Dynamic infrared (IR) imaging is an emerging functional imaging modality for the detection of breast cancer without evidence of optimal imaging and diagnostic application. To evaluate dynamic IR imaging in breast cancer diagnostics by comparing a stepwise diagnostic scheme to digital mammography and postoperative histopathology. Dynamic IR imaging of breasts was undertaken preoperatively with a long-wave quantum well (QWIP) and two mid-wave photovoltaic (PV) IR cameras in 10 cases (age 34-80 years) with breast cancer size 6-45 mm on mammography. Image stabilization, two-phase frequency analysis, and two image-processing algorithms were applied. Combining image processing with frequency analysis proved advantageous in detecting breast cancer. The IR imaging process recognized the cancer area independently of tissue density, cancer size, and cancer appearance on mammography. Compared to histopathology, all cancers yielded abnormal analysis results, including one case of ductal carcinoma in situ. Evidence of lymphatic invasion in postoperative histopathology, imaging with PV camera, and image processing with the Wiener filtering combination correlated with highest confidence between normal and cancer tissue measured by the calculated superiority value. Dynamic IR imaging with image-processing-guided frequency analysis is a promising modality for breast cancer detection and may not have the tissue-dependent limitations of mammography. Our results encourage further work on medical IR imaging and comparison to established breast-imaging modalities.

  17. [Radionuclide imaging of neurendocrine tumors: biological basis and diagnostic results].

    PubMed

    Genovese, Eugenio Annibale; Mallardo, Vania; Rossi, Michele; Vaccaro, Andrea; Raucci, Antonio; Della Vecchi, Nicoletta; Romano, Giovanna; Califano, Teresa; Schillirò, Francesco

    2013-01-01

    Many radiopharmaceuticals have been successfully used in nuclear medicine to detect neuroendocrine tumors, and many of them are based on a specific mechanism of uptake, while others are non-specific probes. This "review" focuses on the clinical applications of metaiodobenzylguanidine, (111)In-pentreotide and positron emission tomography (PET) tracers. New avances in diagnostic imaging will be discussed. Molecular imaging serves these diagnostic functions and provides powerful means for non-invasively detecting disease.

  18. Comparing diagnostic tests: a simple graphic using likelihood ratios.

    PubMed

    Biggerstaff, B J

    2000-03-15

    The diagnostic abilities of two or more diagnostic tests are traditionally compared by their respective sensitivities and specificities, either separately or using a summary of them such as Youden's index. Several authors have argued that the likelihood ratios provide a more appropriate, if in practice a less intuitive, comparison. We present a simple graphic which incorporates all these measures and admits easily interpreted comparison of two or more diagnostic tests. We show, using likelihood ratios and this graphic, that a test can be superior to a competitor in terms of predictive values while having either sensitivity or specificity smaller. A decision theoretic basis for the interpretation of the graph is given by relating it to the tent graph of Hilden and Glasziou (Statistics in Medicine, 1996). Finally, a brief example comparing two serodiagnostic tests for Lyme disease is presented. Published in 2000 by John Wiley & Sons, Ltd.

  19. Diagnostic Imaging of Dental Disease in Pet Rabbits and Rodents.

    PubMed

    Capello, Vittorio

    2016-09-01

    Diagnostic imaging techniques are of paramount importance for dentistry and oral disorders of rabbits, rodents, and other exotic companion mammals. Aside from standard radiography, stomatoscopy is a complementary tool allowing a thorough and detailed inspection of the oral cavity. Computed tomography (CT) generates multiple 2-dimensional views and 3-dimensional reconstructions providing superior diagnostic accuracy also useful for prognosis and treatment of advanced dental disease and its related complications. MRI is a diagnostic imaging technique additional to CT used primarily to enhance soft tissues, including complex odontogenic abscesses.

  20. Psychiatric Diagnostic Interviews for Children and Adolescents: A Comparative Study

    ERIC Educational Resources Information Center

    Angold, Adrian; Erkanli, Alaattin; Copeland, William; Goodman, Robert; Fisher, Prudence W.; Costello, E. Jane

    2012-01-01

    Objective: To compare examples of three styles of psychiatric interviews for youth: the Diagnostic Interview Schedule for Children (DISC) ("respondent-based"), the Child and Adolescent Psychiatric Assessment (CAPA) ("interviewer-based"), and the Development and Well-Being Assessment (DAWBA) ("expert judgment"). Method: Roughly equal numbers of…

  1. Psychiatric Diagnostic Interviews for Children and Adolescents: A Comparative Study

    ERIC Educational Resources Information Center

    Angold, Adrian; Erkanli, Alaattin; Copeland, William; Goodman, Robert; Fisher, Prudence W.; Costello, E. Jane

    2012-01-01

    Objective: To compare examples of three styles of psychiatric interviews for youth: the Diagnostic Interview Schedule for Children (DISC) ("respondent-based"), the Child and Adolescent Psychiatric Assessment (CAPA) ("interviewer-based"), and the Development and Well-Being Assessment (DAWBA) ("expert judgment"). Method: Roughly equal numbers of…

  2. TH-A-BRF-11: Image Intensity Non-Uniformities Between MRI Simulation and Diagnostic MRI

    SciTech Connect

    Paulson, E

    2014-06-15

    Purpose: MRI simulation for MRI-based radiotherapy demands that patients be setup in treatment position, which frequently involves use of alternative radiofrequency (RF) coil configurations to accommodate immobilized patients. However, alternative RF coil geometries may exacerbate image intensity non-uniformities (IINU) beyond those observed in diagnostic MRI, which may challenge image segmentation and registration accuracy as well as confound studies assessing radiotherapy response when MR simulation images are used as baselines for evaluation. The goal of this work was to determine whether differences in IINU exist between MR simulation and diagnostic MR images. Methods: ACR-MRI phantom images were acquired at 3T using a spin-echo sequence (TE/TR:20/500ms, rBW:62.5kHz, TH/skip:5/5mm). MR simulation images were obtained by wrapping two flexible phased-array RF coils around the phantom. Diagnostic MR images were obtained by placing the phantom into a commercial phased-array head coil. Pre-scan normalization was enabled in both cases. Images were transferred offline and corrected for IINU using the MNI N3 algorithm. Coefficients of variation (CV=σ/μ) were calculated for each slice. Wilcoxon matched-pairs and Mann-Whitney tests compared CV values between original and N3 images and between MR simulation and diagnostic MR images. Results: Significant differences in CV were detected between original and N3 images in both MRI simulation and diagnostic MRI groups (p=0.010, p=0.010). In addition, significant differences in CV were detected between original MR simulation and original and N3 diagnostic MR images (p=0.0256, p=0.0016). However, no significant differences in CV were detected between N3 MR simulation images and original or N3 diagnostic MR images, demonstrating the importance of correcting MR simulation images beyond pre-scan normalization prior to use in radiotherapy. Conclusions: Alternative RF coil configurations used in MRI simulation can Result in

  3. Cancer Risks Associated with External Radiation From Diagnostic Imaging Procedures

    PubMed Central

    Linet, Martha S.; Slovis, Thomas L.; Miller, Donald L.; Kleinerman, Ruth; Lee, Choonsik; Rajaraman, Preetha; de Gonzalez, Amy Berrington

    2012-01-01

    The 600% increase in medical radiation exposure to the US population since 1980 has provided immense benefit, but potential future cancer risks to patients. Most of the increase is from diagnostic radiologic procedures. The objectives of this review are to summarize epidemiologic data on cancer risks associated with diagnostic procedures, describe how exposures from recent diagnostic procedures relate to radiation levels linked with cancer occurrence, and propose a framework of strategies to reduce radiation from diagnostic imaging in patients. We briefly review radiation dose definitions, mechanisms of radiation carcinogenesis, key epidemiologic studies of medical and other radiation sources and cancer risks, and dose trends from diagnostic procedures. We describe cancer risks from experimental studies, future projected risks from current imaging procedures, and the potential for higher risks in genetically susceptible populations. To reduce future projected cancers from diagnostic procedures, we advocate widespread use of evidence-based appropriateness criteria for decisions about imaging procedures, oversight of equipment to deliver reliably the minimum radiation required to attain clinical objectives, development of electronic lifetime records of imaging procedures for patients and their physicians, and commitment by medical training programs, professional societies, and radiation protection organizations to educate all stakeholders in reducing radiation from diagnostic procedures. PMID:22307864

  4. Cancer risks associated with external radiation from diagnostic imaging procedures.

    PubMed

    Linet, Martha S; Slovis, Thomas L; Miller, Donald L; Kleinerman, Ruth; Lee, Choonsik; Rajaraman, Preetha; Berrington de Gonzalez, Amy

    2012-01-01

    The 600% increase in medical radiation exposure to the US population since 1980 has provided immense benefit, but increased potential future cancer risks to patients. Most of the increase is from diagnostic radiologic procedures. The objectives of this review are to summarize epidemiologic data on cancer risks associated with diagnostic procedures, describe how exposures from recent diagnostic procedures relate to radiation levels linked with cancer occurrence, and propose a framework of strategies to reduce radiation from diagnostic imaging in patients. We briefly review radiation dose definitions, mechanisms of radiation carcinogenesis, key epidemiologic studies of medical and other radiation sources and cancer risks, and dose trends from diagnostic procedures. We describe cancer risks from experimental studies, future projected risks from current imaging procedures, and the potential for higher risks in genetically susceptible populations. To reduce future projected cancers from diagnostic procedures, we advocate the widespread use of evidence-based appropriateness criteria for decisions about imaging procedures; oversight of equipment to deliver reliably the minimum radiation required to attain clinical objectives; development of electronic lifetime records of imaging procedures for patients and their physicians; and commitment by medical training programs, professional societies, and radiation protection organizations to educate all stakeholders in reducing radiation from diagnostic procedures.

  5. The clinician's guide to diagnostic imaging

    SciTech Connect

    Grossman, Z.D.; Ellis, D.A.; Brigham, S.C.

    1983-01-01

    ''Contains accurate and essential information on the imaging work-up of many clinical problems. It is best suited for medical students, house staff, and general practitioners who need a quick and easy basic reference when choosing among the various imaging modalities.'' -Radiology ''A practical manual designed for clinicians at any level....Provides a clear working framework.'' -Lancet ''The clarity of the text...is refreshing...It should be read by both referring physicians and imaging specialists.'' This pocket manual provides clinicians, house officers, and medical students with the first practical guide to the most appropriate, cost-effective use of computed tomography, ultrasound, nuclear medicine, and radiography. For each of 42 medical, surgical, and pediatric problems whose workup depends upon imaging, the text presents a logical, step-by-step imaging sequence, outlining the most direct, least invasive route to a diagnosis.

  6. [Imaging and Laboratory Diagnostics for Tuberculosis].

    PubMed

    Bauer, C M; Schmähl, A; Kreuter, M

    2016-05-01

    Diagnosis of tuberculosis (TB) is difficult, since symptoms are often very unspecific or lacking. However active, prompt and accurate diagnosis is the key element in the public health response to tuberculosis and the cornerstone of tuberculosis control. Different diagnostic methods for an assured diagnosis of TB are necessary. Chest radiography is a useful keystone to identify tuberculosis, but diagnosis of tuberculosis cannot be established by radiography alone. CT scanning is used in patients without pathological chest radiography but clinically suspected active TB and to differentiate TB from other diseases. Radiological appearance is primarily determined by the immune status of patients and caverns and disseminated disease foci are often observed. Laboratory diagnostic methods include microscopic identification of acid-fast mycobacteria from any body fluid (especially sputum), as well as isolation and characterisation of mycobacteria in culture. It is then possible to type the pathogens by the shape of their colony, their growth behavior and their biochemical characteristics. These methods are regarded as the gold standard in diagnosis of active TB. In patients who are highly suspected of having TB, but whose sputum specimens tested negative for mycobacteria, a nucleic acid amplification test is additionally performed. Moreover, sensitivity testing with first and second line antitubercular drugs is applied as standard. Laboratory diagnostic testing of cellular immunity against pathogenic mycobacteria employs the tuberculin skin test (TST, Mantoux tuberculin test) or the more specific interferon γ test to determine γ interferon released by T lymphocytes stimulated in vitro. The new ELISA and ELISPOT procedures exhibit higher test specificity and less cross reactivity to NTM (non-tuberculosis mycobacteria), are independent of BCG-vaccination status and correlate better with the degree of exposure than does the TST. Georg Thieme Verlag KG Stuttgart · New York.

  7. Semiconductor Circuit Diagnostics By Magnetic Field Imaging

    NASA Astrophysics Data System (ADS)

    Venkatesan, T.

    2011-03-01

    At the forefront of IC technology development are 3D circuit technologies such as system-in-package (SiP), wafer-level-packaging (WLP), through-silicon-vias (TSV), stacked die approaches, flex packages, etc. They integrate multiple devices, many times stacking them in layers with complex, intricate and very long interconnections in significantly reduced area, in addition to an ever-increasing number of opaque layers.~ We could very well say that the near future looks like the perfect nightmare for the Failure Analysis (FA) engineer with localization of defects becoming a major challenge. Magnetic field imaging (MFI) allows the fields generated by the circuit currents to go through various packaging layers and be imaged. I will describe in this talk Magma, a scanning magnetic field imaging system based on a high temperature superconducting SQUID device based on YBa2Cu3O7- δ . The HTS SQUIDs used have a noise level of ~ 20 pT/ √ (Hz) and for typical scanning conditions, a field sensitivity of about 0.7 nT. While current shorts are imaged with spatial resolution, up to 3 micron (with peak localization) resistive opens can also be imaged and currently different strategies are being adapted for imaging opens with large working distances of 50-100s of microns. Higher spatial resolution (~ 250 nm) is obtained by the use of magneto-resistive devices as sensors though the working distance requirement is sever

  8. Imaging polarimetry as a diagnostic tool

    NASA Astrophysics Data System (ADS)

    Gledhill, Tim M.

    2009-04-01

    Some of the earliest polarimetric measurements made in astronomy were concerned with the polarization of the interstellar medium resulting from dust grains aligned in the Galactic magnetic field. More than 50 years later, polarimetry continues to be an important diagnostic of field structure on size scales ranging from planetary to galactic. The use of both linear and circular polarimetry at optical and infrared wavelengths can provide additional insights into the nature of dust particles, their alignment in magnetic fields and the field topology. Given the science benefits that polarimetry offers it is perhaps surprising that the continued existence of polarimetric facilities on current and next generation large telescopes needs to be ensured.

  9. Lensless Imaging for Battlefield On-Chip Blood Diagnostics

    DTIC Science & Technology

    2010-12-06

    University of Southern California (USC), 28 April 2010, Los Angeles CA 15. A. Ozcan, “Incoherent Lensfree Cell Holography for Global Health...Multi-angle Lensless Holography for Depth Resolved High-throughput Imaging of Cells On a Chip,” IEEE Photonics Society, Winter Topical Meeting on...and A. Ozcan, “Incoherent On-chip Cell Holography for Sub-cellular Imaging and Point-of-Care Diagnostics,” SPIE Photonics West Conference, Imaging

  10. Modifications to the synthetic aperture microwave imaging diagnostic

    DOE PAGES

    Brunner, K. J.; Chorley, J. C.; Dipper, N. A.; ...

    2016-09-02

    The synthetic aperture microwave imaging diagnostic has been operating on the MAST experiment since 2011. It has provided the first 2D images of B-X-O mode conversion windows and showed the feasibility of conducting 2D Doppler back-scattering experiments. The diagnostic heavily relies on field programmable gate arrays to conduct its work. Recent successes and newly gained experience with the diagnostic have led us to modify it. The enhancements will enable pitch angle profile measurements, O and X mode separation, and the continuous acquisition of 2D DBS data. Finally, the diagnostic has also been installed on the NSTX-U and is acquiring datamore » since May 2016.« less

  11. Diagnostic time in digital pathology: A comparative study on 400 cases

    PubMed Central

    Vodovnik, Aleksandar

    2016-01-01

    Background: Numerous validation studies in digital pathology confirmed its value as a diagnostic tool. However, a longer time to diagnosis than traditional microscopy has been seen as a significant barrier to the routine use of digital pathology. As a part of our validation study, we compared a digital and microscopic diagnostic time in the routine diagnostic setting. Materials and Methods: One senior staff pathologist reported 400 consecutive cases in histology, nongynecological, and fine needle aspiration cytology (20 sessions, 20 cases/session), over 4 weeks. Complex, difficult, and rare cases were excluded from the study to reduce the bias. A primary diagnosis was digital, followed by traditional microscopy, 6 months later, with only request forms available for both. Microscopic slides were scanned at ×20, digital images accessed through the fully integrated laboratory information management system (LIMS) and viewed in the image viewer on double 23” displays. A median broadband speed was 299 Mbps. A diagnostic time was measured from the point slides were made available to the point diagnosis was made or additional investigations were deemed necessary, recorded independently in minutes/session and compared. Results: A digital diagnostic time was 1841 and microscopic 1956 min; digital being shorter than microscopic in 13 sessions. Four sessions with shorter microscopic diagnostic time included more cases requiring extensive use of magnifications over ×20. Diagnostic time was similar in three sessions. Conclusions: A diagnostic time in digital pathology can be shorter than traditional microscopy in the routine diagnostic setting, with adequate and stable network speeds, fully integrated LIMS and double displays as default parameters. This also related to better ergonomics, larger viewing field, and absence of physical slide handling, with effects on both diagnostic and nondiagnostic time. Differences with previous studies included a design, image size, number

  12. Compare diagnostic tests using transformation-invariant smoothed ROC curves⋆

    PubMed Central

    Tang, Liansheng; Du, Pang; Wu, Chengqing

    2012-01-01

    Receiver operating characteristic (ROC) curve, plotting true positive rates against false positive rates as threshold varies, is an important tool for evaluating biomarkers in diagnostic medicine studies. By definition, ROC curve is monotone increasing from 0 to 1 and is invariant to any monotone transformation of test results. And it is often a curve with certain level of smoothness when test results from the diseased and non-diseased subjects follow continuous distributions. Most existing ROC curve estimation methods do not guarantee all of these properties. One of the exceptions is Du and Tang (2009) which applies certain monotone spline regression procedure to empirical ROC estimates. However, their method does not consider the inherent correlations between empirical ROC estimates. This makes the derivation of the asymptotic properties very difficult. In this paper we propose a penalized weighted least square estimation method, which incorporates the covariance between empirical ROC estimates as a weight matrix. The resulting estimator satisfies all the aforementioned properties, and we show that it is also consistent. Then a resampling approach is used to extend our method for comparisons of two or more diagnostic tests. Our simulations show a significantly improved performance over the existing method, especially for steep ROC curves. We then apply the proposed method to a cancer diagnostic study that compares several newly developed diagnostic biomarkers to a traditional one. PMID:22639484

  13. Diagnostic imaging for dental implant therapy.

    PubMed

    Nagarajan, Aishwarya; Perumalsamy, Rajapriya; Thyagarajan, Ramakrishnan; Namasivayam, Ambalavanan

    2014-01-01

    Dental implant is a device made of alloplastic (foreign) material implanted into the jaw bone beneath the mucosal layer to support a fixed or removable dental prosthesis. Dental implants are gaining immense popularity and wide acceptance because they not only replace lost teeth but also provide permanent restorations that do not interfere with oral function or speech or compromise the self-esteem of a patient. Appropriate treatment planning for replacement of lost teeth is required and imaging plays a pivotal role to ensure a satisfactory outcome. The development of pre-surgical imaging techniques and surgical templates helps the dentist place the implants with relative ease. This article focuses on various types of imaging modalities that have a pivotal role in implant therapy.

  14. Diagnostic Imaging for Dental Implant Therapy

    PubMed Central

    Nagarajan, Aishwarya; Perumalsamy, Rajapriya; Thyagarajan, Ramakrishnan; Namasivayam, Ambalavanan

    2014-01-01

    Dental implant is a device made of alloplastic (foreign) material implanted into the jaw bone beneath the mucosal layer to support a fixed or removable dental prosthesis. Dental implants are gaining immense popularity and wide acceptance because they not only replace lost teeth but also provide permanent restorations that do not interfere with oral function or speech or compromise the self-esteem of a patient. Appropriate treatment planning for replacement of lost teeth is required and imaging plays a pivotal role to ensure a satisfactory outcome. The development of pre-surgical imaging techniques and surgical templates helps the dentist place the implants with relative ease. This article focuses on various types of imaging modalities that have a pivotal role in implant therapy. PMID:25379354

  15. Development of a synthetic phase contrast imaging diagnostic

    SciTech Connect

    Rost, J. C.; Lin, L.; Porkolab, M.

    2010-06-15

    A ''synthetic diagnostic'' has been developed to calculate the expected experimental response of phase contrast imaging (PCI), a scattering diagnostic used to measure density fluctuations in laboratory plasmas, to a tokamak discharge modeled with the GYRO nonlinear gyrokinetic code [J. Candy and R. Waltz, J. Comput. Phys. 186, 545 (2003)]. The synthetic PCI includes the spatial response of the experimental diagnostic, primarily implemented as a line integral of plasma density along the beam path, and the minimum and maximum wavenumber response resulting from the detection scheme. The synthetic PCI can be used for comparisons between GYRO and experiment as well as studies of the PCI response.

  16. Gold Nanoconstructs for Multimodal Diagnostic Imaging and Photothermal Cancer Therapy

    NASA Astrophysics Data System (ADS)

    Coughlin, Andrew James

    Cancer accounts for nearly 1 out of every 4 deaths in the United States, and because conventional treatments are limited by morbidity and off-target toxicities, improvements in cancer management are needed. This thesis further develops nanoparticle-assisted photothermal therapy (NAPT) as a viable treatment option for cancer patients. NAPT enables localized ablation of disease because heat generation only occurs where tissue permissive near-infrared (NIR) light and absorbing nanoparticles are combined, leaving surrounding normal tissue unharmed. Two principle approaches were investigated to improve the specificity of this technique: multimodal imaging and molecular targeting. Multimodal imaging affords the ability to guide NIR laser application for site-specific NAPT and more holistic characterization of disease by combining the advantages of several diagnostic technologies. Towards the goal of image-guided NAPT, gadolinium-conjugated gold-silica nanoshells were engineered and demonstrated to enhance imaging contrast across a range of diagnostic modes, including T1-weighted magnetic resonance imaging, X-Ray, optical coherence tomography, reflective confocal microscopy, and two-photon luminescence in vitro as well as within an animal tumor model. Additionally, the nanoparticle conjugates were shown to effectively convert NIR light to heat for applications in photothermal therapy. Therefore, the broad utility of gadolinium-nanoshells for anatomic localization of tissue lesions, molecular characterization of malignancy, and mediators of ablation was established. Molecular targeting strategies may also improve NAPT by promoting nanoparticle uptake and retention within tumors and enhancing specificity when malignant and normal tissue interdigitate. Here, ephrinA1 protein ligands were conjugated to nanoshell surfaces for particle homing to overexpressed EphA2 receptors on prostate cancer cells. In vitro, successful targeting and subsequent photothermal ablation of

  17. Infrared Imaging Tools for Diagnostic Applications in Dermatology.

    PubMed

    Gurjarpadhye, Abhijit Achyut; Parekh, Mansi Bharat; Dubnika, Arita; Rajadas, Jayakumar; Inayathullah, Mohammed

    Infrared (IR) imaging is a collection of non-invasive imaging techniques that utilize the IR domain of the electromagnetic spectrum for tissue assessment. A subset of these techniques construct images using back-reflected light, while other techniques rely on detection of IR radiation emitted by the tissue as a result of its temperature. Modern IR detectors sense thermal emissions and produce a heat map of surface temperature distribution in tissues. Thus, the IR spectrum offers a variety of imaging applications particularly useful in clinical diagnostic area, ranging from high-resolution, depth-resolved visualization of tissue to temperature variation assessment. These techniques have been helpful in the diagnosis of many medical conditions including skin/breast cancer, arthritis, allergy, burns, and others. In this review, we discuss current roles of IR-imaging techniques for diagnostic applications in dermatology with an emphasis on skin cancer, allergies, blisters, burns and wounds.

  18. Infrared Imaging Tools for Diagnostic Applications in Dermatology

    PubMed Central

    Gurjarpadhye, Abhijit Achyut; Parekh, Mansi Bharat; Dubnika, Arita; Rajadas, Jayakumar; Inayathullah, Mohammed

    2015-01-01

    Infrared (IR) imaging is a collection of non-invasive imaging techniques that utilize the IR domain of the electromagnetic spectrum for tissue assessment. A subset of these techniques construct images using back-reflected light, while other techniques rely on detection of IR radiation emitted by the tissue as a result of its temperature. Modern IR detectors sense thermal emissions and produce a heat map of surface temperature distribution in tissues. Thus, the IR spectrum offers a variety of imaging applications particularly useful in clinical diagnostic area, ranging from high-resolution, depth-resolved visualization of tissue to temperature variation assessment. These techniques have been helpful in the diagnosis of many medical conditions including skin/breast cancer, arthritis, allergy, burns, and others. In this review, we discuss current roles of IR-imaging techniques for diagnostic applications in dermatology with an emphasis on skin cancer, allergies, blisters, burns and wounds. PMID:26691203

  19. A review of diagnostic imaging of snakes and lizards.

    PubMed

    Banzato, T; Hellebuyck, T; Van Caelenberg, A; Saunders, J H; Zotti, A

    2013-07-13

    Snakes and lizards are considered 'stoic' animals and often show only non-specific signs of illness. Consequently, diagnostic imaging--along with clinical examination and laboratory tests--is gaining importance in making a final diagnosis and establishing a correct therapy. The large number of captive snake and lizard species commonly kept as pets, together with the high inter- and intraspecific morphological variability that is innate in these animals, make the analysis of diagnostic images challenging for the veterinary practitioner. Moreover, a thorough knowledge of the anatomy, physiology and pathology of the species that are the object of clinical investigation is mandatory for the correct interpretation of diagnostic images. Despite the large amount of clinical and scientific work carried out in the past two decades, the radiographic features of snakes and lizards have not undergone systematic description, and therefore veterinarians often have to rely mostly on anatomical studies rather than radiological literature. The aim of this paper is to review the most commonly used diagnostic imaging modalities, as well as to provide an overview of the available international original studies and scientific reviews describing the normal and pathological imaging features in snakes and lizards.

  20. Non-invasive diagnostic imaging of colorectal liver metastases

    PubMed Central

    Mainenti, Pier Paolo; Romano, Federica; Pizzuti, Laura; Segreto, Sabrina; Storto, Giovanni; Mannelli, Lorenzo; Imbriaco, Massimo; Camera, Luigi; Maurea, Simone

    2015-01-01

    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases (CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liver-directed therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs. PMID:26217455

  1. Non-invasive diagnostic imaging of colorectal liver metastases.

    PubMed

    Mainenti, Pier Paolo; Romano, Federica; Pizzuti, Laura; Segreto, Sabrina; Storto, Giovanni; Mannelli, Lorenzo; Imbriaco, Massimo; Camera, Luigi; Maurea, Simone

    2015-07-28

    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases (CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liver-directed therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs.

  2. Healthcare provider and patient perspectives on diagnostic imaging investigations.

    PubMed

    Makanjee, Chandra R; Bergh, Anne-Marie; Hoffmann, Willem A

    2015-05-20

    Much has been written about the patient-centred approach in doctor-patient consultations. Little is known about interactions and communication processes regarding healthcare providers' and patients' perspectives on expectations and experiences of diagnostic imaging investigations within the medical encounter. Patients journey through the health system from the point of referral to the imaging investigation itself and then to the post-imaging consultation. AIM AND SETTING: To explore healthcare provider and patient perspectives on interaction and communication processes during diagnostic imaging investigations as part of their clinical journey through a healthcare complex. A qualitative study was conducted, with two phases of data collection. Twenty-four patients were conveniently selected at a public district hospital complex and were followed throughout their journey in the hospital system, from admission to discharge. The second phase entailed focus group interviews conducted with providers in the district hospital and adjacent academic hospital (medical officers and family physicians, nurses, radiographers, radiology consultants and registrars). Two main themes guided our analysis: (1) provider perspectives; and (2) patient dispositions and reactions. Golden threads that cut across these themes are interactions and communication processes in the context of expectations, experiences of the imaging investigations and the outcomes thereof. Insights from this study provide a better understanding of the complexity of the processes and interactions between providers and patients during the imaging investigations conducted as part of their clinical pathway. The interactions and communication processes are provider-patient centred when a referral for a diagnostic imaging investigation is included.

  3. Automated image interpretation and computer-assisted diagnostics.

    PubMed

    Foran, David J; Chen, Wenjin; Yang, Lin

    2013-01-01

    Much of the difficulty in reaching consistent evaluations of radiology and pathology imaging studies arises from subjective impressions of individual observers. Developing strategies that can reliably transform complex visual observations into well-defined algorithmic procedures is an active area of exploration which can advance clinical practice, investigative research and outcome studies. The literature shows that when characterizations are based upon computer-aided analysis, objectivity, reproducibility and sensitivity improve considerably. Advanced imaging and computational tools could potentially enable investigators to detect and track subtle changes in measurable parameters leading to the discovery of novel diagnostic and prognostic clues which are not apparent by human visual inspection alone. The overarching objective of this book chapter is to provide readers with a summary of the origin, evolution and future directions for the fields of automated image interpretation and computer-assisted diagnostics. The chapter begins with a high-level overview of the fields of image processing, pattern recognition, and computer vision followed by a description of how these disciplines relate to the more comprehensive fields of computer-assisted diagnostics and image guided decision support. Throughout the remainder of the chapter we have supplied multiple illustrative examples demonstrating how recent advances and innovations in each of these areas have impacted clinical and research activities throughout pathology and radiology including high-throughput tissue microarray analysis, multi-spectral imaging, and image co-registration.

  4. Diagnostic Imaging of the Hepatobiliary System: An Update.

    PubMed

    Marolf, Angela J

    2017-05-01

    Recent advances in diagnostic imaging of the hepatobiliary system include MRI, computed tomography (CT), contrast-enhanced ultrasound, and ultrasound elastography. With the advent of multislice CT scanners, sedated examinations in veterinary patients are feasible, increasing the utility of this imaging modality. CT and MRI provide additional information for dogs and cats with hepatobiliary diseases due to lack of superimposition of structures, operator dependence, and through intravenous contrast administration. Advanced ultrasound methods can offer complementary information to standard ultrasound imaging. These newer imaging modalities assist clinicians by aiding diagnosis, prognostication, and surgical planning. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. [Auto-Immune Pancreatitis: The Diagnostic Role of Imaging Studies].

    PubMed

    Ressurreição, João; Bali, Maria; Matos, Celso

    2015-01-01

    Auto-immune pancreatitis is an uncommon and underdiagnosed pathology. Its clinical picture is not specific and the diagnosis is therefore difficult. Imaging studies have a crucial role in the diagnostic process and also in the follow-up of treatment. With the objective of emphasizing the importance of imaging in the correct diagnosis of this pathology, the authors report the case of a patient with longterm unspecific abdominal complaints that was diagnosed as auto-immune pancreatitis after laboratorial and imaging investigation. Assuming this diagnosis it was instituted treatment with oral methylprednisolone, which succeeded, with progressive resolution of the clinical, laboratorial and imaging findings.

  6. DIAGNOSTIC IMAGING OF THE THROWING ATHLETE’S SHOULDER

    PubMed Central

    Hazle, Charles

    2013-01-01

    The diagnostic capabilities of advanced imaging have increasingly enabled clinicians to delineate between structural alterations and injuries more efficiently than ever before. These impressive gains have unfortunately begun to provide a reliance on imaging at the loss of quality in the clinical examination. Ideally, imaging of the shoulder complex is performed to confirm the provisional diagnosis developed from the history and clinical exam rather than to create such. This clinical commentary will provide the framework for both basic and advanced uses of imaging as well as discussion of evolving modalities. Level of Evidence: 5 PMID:24175143

  7. Acute Cholecystitis: The Diagnostic Role for Current Imaging Tests

    PubMed Central

    Krishnamurthy, Gerbail T.

    1982-01-01

    Acute cholecystitis is a relatively common clinical entity characterized histopathologically by obstruction of the cystic duct due to either edema or stone or both. Thorough clinical assessment and selection of the appropriate diagnostic tests are crucial in making an early diagnosis before surgical treatment. Many diagnostic tests are available for imaging the gallbladder. Hepatobiliary imaging using technetium Tc 99m IDA is the test of choice to either exclude or confirm the diagnosis of acute cholecystitis and it carries a discriminating power greater than that of cholecystography or ultrasonography. In most patients the exclusion of the diagnosis of acute cholecystitis can be made as early as 30 minutes and the confirmation within three hours. The confirmation of acute cholecystitis by radionuclide imaging obviates the need for either cholecystography or ultrasonography. ImagesFigure 1. PMID:6753344

  8. Diagnostic value of imaging in infective endocarditis: a systematic review.

    PubMed

    Gomes, Anna; Glaudemans, Andor W J M; Touw, Daan J; van Melle, Joost P; Willems, Tineke P; Maass, Alexander H; Natour, Ehsan; Prakken, Niek H J; Borra, Ronald J H; van Geel, Peter Paul; Slart, Riemer H J A; van Assen, Sander; Sinha, Bhanu

    2017-01-01

    Sensitivity and specificity of the modified Duke criteria for native valve endocarditis are both suboptimal, at approximately 80%. Diagnostic accuracy for intracardiac prosthetic material-related infection is even lower. Non-invasive imaging modalities could potentially improve diagnosis of infective endocarditis; however, their diagnostic value is unclear. We did a systematic literature review to critically appraise the evidence for the diagnostic performance of these imaging modalities, according to PRISMA and GRADE criteria. We searched PubMed, Embase, and Cochrane databases. 31 studies were included that presented original data on the performance of electrocardiogram (ECG)-gated multidetector CT angiography (MDCTA), ECG-gated MRI, (18)F-fluorodeoxyglucose ((18)F-FDG) PET/CT, and leucocyte scintigraphy in diagnosis of native valve endocarditis, intracardiac prosthetic material-related infection, and extracardiac foci in adults. We consistently found positive albeit weak evidence for the diagnostic benefit of (18)F-FDG PET/CT and MDCTA. We conclude that additional imaging techniques should be considered if infective endocarditis is suspected. We propose an evidence-based diagnostic work-up for infective endocarditis including these non-invasive techniques. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Disposable blast shields for use on NIF imaging diagnostics

    NASA Astrophysics Data System (ADS)

    Smith, Cal A.; Wang, Karen M.; Masters, Nathan

    2015-08-01

    The NIFs 192 lasers can deliver 2 MJ of energy to Target Chamber Center (TCC) to produce environments not available in any other experimental laboratory. The NIFs ability to deliver such intense energy to a small volume causes harsh consequences to experimental equipment and supporting diagnostics such as holhraums, support packages, target positioners, diagnostic equipment, and laser optics. Of these, the hohlraum and support packages are typically quickly vaporized and transformed into an expanding shell of high-hypersonic gases referred to as debris wind. During an experimental event such as fusion implosion, the target diagnostic components used to measure key observables in the experiment are subjected to extreme pressures and impact shocks due to incident debris wind loading. As diagnostics are positioned closer to TCC, the diagnostic pinhole stacks and other components along the diagnostic structure become more likely to be at or above the yield strength of the materials commonly used. In particular, the pinhole stack components and data recording instruments behind the pinholes are the most costly to replace. Thus, a conceptual configuration for a pinhole shield is proposed, analyzed, and tested with the intent of mitigating damage to the pinhole stack and imaging equipment and allowing immediate re-use of this diagnostic equipment. This pinhole shield would be a replaceable window that can be replaced quickly by inserting and removing it before and after each experimental laser shot, which will allow NIF to benefit from significant material and labor costs.

  10. Present Practice And Perceived Needs-Managing Diagnostic Images

    NASA Astrophysics Data System (ADS)

    Vanden Brink, John A.

    1982-01-01

    With the advent of digital radiography and the installed base of CT, Nuclear Medicine and Ultrasound Scanners numbering in the thousands and the potential of NMR, the market potential for the electronic management of digital images is perhaps one of the most exciting, fastest growing (and most ill defined) fields in medicine today. New technology in optical data storage, electronic transmission, image reproduction, microprocessing, automation and software development provide the promise of a whole new generation of products which will simplify and enhance the diagnostic process (thereby hopefully improving diagnostic accuracy), enable implementation of archival review in a practical sense, expand the availability of diagnostic data and lower the cost/case by at least an order of magnitude.

  11. Diagnostic imaging advances in murine models of colitis.

    PubMed

    Brückner, Markus; Lenz, Philipp; Mücke, Marcus M; Gohar, Faekah; Willeke, Peter; Domagk, Dirk; Bettenworth, Dominik

    2016-01-21

    Inflammatory bowel diseases (IBD) such as Crohn's disease and ulcerative colitis are chronic-remittent inflammatory disorders of the gastrointestinal tract still evoking challenging clinical diagnostic and therapeutic situations. Murine models of experimental colitis are a vital component of research into human IBD concerning questions of its complex pathogenesis or the evaluation of potential new drugs. To monitor the course of colitis, to the present day, classical parameters like histological tissue alterations or analysis of mucosal cytokine/chemokine expression often require euthanasia of animals. Recent advances mean revolutionary non-invasive imaging techniques for in vivo murine colitis diagnostics are increasingly available. These novel and emerging imaging techniques not only allow direct visualization of intestinal inflammation, but also enable molecular imaging and targeting of specific alterations of the inflamed murine mucosa. For the first time, in vivo imaging techniques allow for longitudinal examinations and evaluation of intra-individual therapeutic response. This review discusses the latest developments in the different fields of ultrasound, molecularly targeted contrast agent ultrasound, fluorescence endoscopy, confocal laser endomicroscopy as well as tomographic imaging with magnetic resonance imaging, computed tomography and fluorescence-mediated tomography, discussing their individual limitations and potential future diagnostic applications in the management of human patients with IBD.

  12. Method to directly radiolabel antibodies for diagnostic imaging and therapy

    SciTech Connect

    Thakur, M.L.

    1991-04-30

    This patent describes a method for directly labeling proteins with radionuclides for use in diagnostic imaging and therapy. It comprises: the steps of incubating a protein-containing solution with a solution of sodium ascorbate; adding a required quantity of reduced radionuclide to the incubated protein-containing solution and incubating.

  13. Diagnostic Medical Imaging in Pediatric Patients and Subsequent Cancer Risk.

    PubMed

    Mulvihill, David J; Jhawar, Sachin; Kostis, John B; Goyal, Sharad

    2017-06-20

    The use of diagnostic medical imaging is becoming increasingly more commonplace in the pediatric setting. However, many medical imaging modalities expose pediatric patients to ionizing radiation, which has been shown to increase the risk of cancer development in later life. This review article provides a comprehensive overview of the available data regarding the risk of cancer development following exposure to ionizing radiation from diagnostic medical imaging. Attention is paid to modalities such as computed tomography scans and fluoroscopic procedures that can expose children to radiation doses orders of magnitude higher than standard diagnostic x-rays. Ongoing studies that seek to more precisely determine the relationship of diagnostic medical radiation in children and subsequent cancer development are discussed, as well as modern strategies to better quantify this risk. Finally, as cardiovascular imaging and intervention contribute substantially to medical radiation exposure, we discuss strategies to enhance radiation safety in these areas. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  14. Phyllodes tumor: diagnostic imaging and histopathology findings.

    PubMed

    Venter, Alina Cristiana; Roşca, Elena; Daina, Lucia Georgeta; Muţiu, Gabriela; Pirte, Adriana Nicoleta; Rahotă, Daniela

    2015-01-01

    Phyllodes tumors are rare breast tumors, accounting for less than 1% of all primary tumors of the breast. Histologically, phyllodes tumors can be divided into benign (60%), borderline (20%) and malignant (20%). The mammography examination was performed by means of a digital mammography system Giotto 3D Images; the ultrasound examination was performed through a GE Logiq P6 device and histological confirmation was possible after surgery or following the histological biopsy. We grouped the nine patients who presented clinically palpable nodules into two groups, namely: the six patients presenting histological benign results into Group I, and Group II where we included those with borderline and malignant histological results. Mammography performed in 77.7% revealed a well-circumscribed round or oval opacity or with contour lobules. Ultrasound examination was performed in all patients. Mammography and ultrasound have limitation in differentiating between benign lesion and phyllodes tumor. In the nine analyzed cases, mammographic and ultrasound examinations did not allow the differentiation into the three groups of phyllodes tumor. Histopathological examination is considered the golden standard for their diagnosis. Correlations between mammographic and microscopic aspects were inconclusive for determining the degree of differentiation, ultrasound changes could be correlated with the histopathological aspects.

  15. Autofluorescence-based diagnostic UV imaging of tissues and cells

    NASA Astrophysics Data System (ADS)

    Renkoski, Timothy E.

    Cancer is the second leading cause of death in the United States, and its early diagnosis is critical to improving treatment options and patient outcomes. In autofluorescence (AF) imaging, light of controlled wavelengths is projected onto tissue, absorbed by specific molecules, and re-emitted at longer wavelengths. Images of re-emitted light are used together with spectral information to infer tissue functional information and diagnosis. This dissertation describes AF imaging studies of three different organs using data collected from fresh human surgical specimens. In the ovary study, illumination was at 365 nm, and images were captured at 8 emission wavelengths. Measurements from a multispectral imaging system and fiber optic probe were used to map tissue diagnosis at every image pixel. For the colon and pancreas studies, instrumentation was developed extending AF imaging capability to sub-300 nm excitation. Images excited in the deep UV revealed tryptophan and protein content which are believed to change with disease state. Several excitation wavelength bands from 280 nm to 440 nm were investigated. Microscopic AF images collected in the pancreas study included both cultured and primary cells. Several findings are reported. A method of transforming fiber optic probe spectra for direct comparison with imager spectra was devised. Normalization of AF data by green reflectance data was found useful in correcting hemoglobin absorption. Ratio images, both AF and reflectance, were formulated to highlight growths in the colon. Novel tryptophan AF images were found less useful for colon diagnostics than the new ratio techniques. Microscopic tryptophan AF images produce useful visualization of cellular protein content, but their diagnostic value requires further study.

  16. The Astronomy Diagnostic Test: Comparing Your Class to Others

    NASA Astrophysics Data System (ADS)

    Hufnagel, B.; Deming, G.

    1999-05-01

    A standard diagnostic test can be a powerful tool to assess the conceptual understanding of students, as has been proven for undergraduate physics instruction over the last ten years (e.g., E.F. Redish and R.N. Steinberg 1999, Physics Today, 52:1, 24). If you are now using, or are considering adopting, a more interactive teaching style such as that used by Eric Mazur (Peer Instruction: a User's Manual, [Prentice-Hall: 1997]) or Michael Zeilik and his collaborators (1997, AJP, 65:12, 987), you may want to use a standard diagnostic test designed for undergraduate astronomy classes. Details of the validation of the ADT are at Slater et al., also presented in this session. A comparative database of ADT scores, by class and by question, can help the instructor assess student preparedness and the effectiveness of alternative teaching methods. In the spring of 1999, 19 astronomy instructors at 7 state universities, 4 community colleges, 4 liberal arts schools, 1 woman's college and 1 technical university across the USA gave the ADT to their classes once at the beginning of the course, and again at the end of the course. The average pre-course ADT scores by class from these ~ 1000 students show two surprising results: the conceptual understanding of introductory classes is about the same (34%) regardless of type of school, geographic location, or average student age. However, there is a significant gender difference, with females scoring an average of 29% and males 39%, with the standard errors both less than 1%. The Astronomy Diagnostic Test (ADT) and its comparative by-class database will be available at the National Institute for Science Education (NISE) website after 1 June 1999. This research was supported by the National Science Foundation through Grant DGE-9714489, and by the generosity of the participating astronomy instructors.

  17. Inference based on diagnostic measures from studies of new imaging devices.

    PubMed

    Samuelson, Frank W

    2013-07-01

    Before using a new diagnostic imaging device regularly in a clinic, it should be studied using patients and radiologists. Often such studies report diagnostic performance in terms of sensitivity, specificity, area under the receiver operating characteristic curve (AUC), or differences thereof. In this report we look at how these studies differ from actual future clinical practice and how those differences may affect reported performance measures. We review signal detection (receiver operating characteristic) theory and decision theory. We compare diagnostic measures from several published studies in medical imaging and examine how they relate to theory and each other. We see that clinical decisions can be modeled using signal detection and decision theories. Sensitivity and specificity are inextricably linked with clinical factors, such as prevalence and costs. Imaging devices are used in many different ways in clinical practice, so that sensitivities, specificities, and AUCs measured in studies of new diagnostic imaging devices will differ from those in actual future clinical use. Measured sensitivities, specificities, and the directions of changes thereof are not necessarily consistent or reproducible across studies of new diagnostic devices. A change in the AUC, which should be independent of clinical costs or prevalence, is a consistent measure across similar studies, and a positive change in AUC is indicative of additional diagnostic information that will be available to radiologists in a future clinical environment. Published by Elsevier Inc.

  18. Diagnostic accuracy of late iodine-enhancement dual-energy computed tomography for the detection of chronic myocardial infarction compared with late gadolinium-enhancement 3-T magnetic resonance imaging.

    PubMed

    Wichmann, Julian L; Bauer, Ralf W; Doss, Mirko; Stock, Wenzel; Lehnert, Thomas; Bodelle, Boris; Frellesen, Claudia; Vogl, Thomas J; Kerl, J Matthias

    2013-12-01

    The purpose of the study was to compare the performance of late iodine-enhancement (LIE) dual-energy computed tomography (DECT) linear blending and selective myocardial iodine mapping for the detection of chronic myocardial infarction (CMI) with late gadolinium-enhancement (LGE) 3-T magnetic resonance imaging. This study was approved by the institutional review board, and the patients gave informed consent. A total of 20 patients with a history of CMI underwent cardiac LIE-DECT and LGE-MRI. Images of the LIE-DECT were reconstructed as 100 kilovolt (peak) (kV[p]), 140 kV(p), and weighted-average (WA; linear blending) images from low- and high-kilovoltage peak data using 3 different weighting factors (0.8, 0.6, 0.3). Additional color-coded myocardial iodine distribution maps were calculated. The images were reviewed for the presence of late enhancement, transmural extent, signal characteristics, infarct volume, and subjective image quality. Segmental analysis of LIE-DECT data from 100 kV(p), WA of 0.8, and WA of 0.6 showed identical results for the identification of CMI (89% sensitivity, 98% specificity, 96% accuracy) and correctly identified all segments with transmural scarring detected through LGE-MRI. Weighted average of 0.6 received the best subjective image quality rating (15/20 votes) and average measured infarct size correlated best with LGE-MRI (5.7% difference). In comparison with LGE-MRI, iodine distribution maps were susceptible to false-positive and false-negative findings (52% sensitivity, 88% specificity, 81% accuracy), overestimating quantity of transmural scars by 78% while underestimating infarct volume by 55%. Late iodine enhancement cardiac dual-energy computed tomography correlates well with LGE-MRI for detecting CMI, whereas iodine distribution analysis provides inferior accuracy. Linear blending further improves image quality and enables more precise estimation of scar volume.

  19. Diagnostic imaging over the last 50 years: research and development in medical imaging science and technology.

    PubMed

    Doi, Kunio

    2006-07-07

    Over the last 50 years, diagnostic imaging has grown from a state of infancy to a high level of maturity. Many new imaging modalities have been developed. However, modern medical imaging includes not only image production but also image processing, computer-aided diagnosis (CAD), image recording and storage, and image transmission, most of which are included in a picture archiving and communication system (PACS). The content of this paper includes a short review of research and development in medical imaging science and technology, which covers (a) diagnostic imaging in the 1950s, (b) the importance of image quality and diagnostic performance, (c) MTF, Wiener spectrum, NEQ and DQE, (d) ROC analysis, (e) analogue imaging systems, (f) digital imaging systems, (g) image processing, (h) computer-aided diagnosis, (i) PACS, (j) 3D imaging and (k) future directions. Although some of the modalities are already very sophisticated, further improvements will be made in image quality for MRI, ultrasound and molecular imaging. The infrastructure of PACS is likely to be improved further in terms of its reliability, speed and capacity. However, CAD is currently still in its infancy, and is likely to be a subject of research for a long time.

  20. Radiation Protection of the Child from Diagnostic Imaging.

    PubMed

    Leung, Rebecca S

    2015-01-01

    In recent years due to the technological advances in imaging techniques, which have undoubtedly improved diagnostic accuracy and resulted in improved patient care, the utilization of ionizing radiation in diagnostic imaging has significantly increased. Computed tomography is the major contributor to the radiation burden, but fluoroscopy continues to be a mainstay in paediatric radiology. The rise in the use of ionizing radiation is of particular concern with regard to the paediatric population, as they are up to 10 times more sensitive to the effects of radiation than adults, due to their increased tissue radiosensitivity, increased cumulative lifetime radiation dose and longer lifetime in which to manifest the effects. This article will review the estimated radiation risk to the child from diagnostic imaging and summarise the various methods through which both the paediatrician and radiologist can practice the ALARA (As Low As Reasonably Achievable) principle, which underpins the safe practice of radiology. Emphasis is on the justification for an examination, i.e. weighing of benefits versus radiation risk, on the appropriate utilization of other, non-ionizing imaging modalities such as ultrasound and magnetic resonance imaging, and on optimisation of a clinically indicated examination. It is essential that the paediatrician and radiologist work together in this decision making process for the mutual benefit of the patient. The appropriate practical application of ALARA in the workplace is crucial to the radiation safety of our paediatric patients.

  1. Quantifying Therapeutic and Diagnostic Efficacy in 2D Microvascular Images

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia; Vickerman, Mary B.; Keith, Patricia A.

    2009-01-01

    VESGEN is a newly automated, user-interactive program that maps and quantifies the effects of vascular therapeutics and regulators on microvascular form and function. VESGEN analyzes two-dimensional, black and white vascular images by measuring important vessel morphology parameters. This software guides the user through each required step of the analysis process via a concise graphical user interface (GUI). Primary applications of the VESGEN code are 2D vascular images acquired as clinical diagnostic images of the human retina and as experimental studies of the effects of vascular regulators and therapeutics on vessel remodeling.

  2. The Comparative Diagnostic Features of Canine and Human Lymphoma

    PubMed Central

    Seelig, Davis M.; Avery, Anne C.; Ehrhart, E. J.; Linden, Michael A.

    2016-01-01

    The non-Hodgkin lymphomas (NHLs) are a heterogeneous family of lymphoid malignancies that are among the most common neoplasms of both dogs and humans. Owing to shared molecular, signaling, incidence, and pathologic features, there is a strong framework supporting the utilization of canine lymphoma as a comparative, large animal model of human NHL. In alignment with the biologic similarities, the current approach towards the diagnosis and classification of canine lymphoma is based upon the human World Health Organization guidelines. While this approach has contributed to an increasing appreciation of the potential biological scope of canine lymphoma, it has also become apparent that the most appropriate diagnostic philosophy must be multimodal, namely by requiring knowledge of microscopic, immunophenotypic, and clinical features before establishing a final disease diagnosis. This review seeks to illustrate the comparative similarities and differences in the diagnosis of canine lymphoma through the presentation of the microscopic and immunophenotypic features of its most common forms. PMID:28435836

  3. Diagnostic Value of Dual-Source Computerized Tomography Combined with Perfusion Imaging for Peripheral Pulmonary Embolism

    PubMed Central

    Mao, Xijin; Wang, Shanshan; Jiang, Xingyue; Zhang, Lin; Xu, Wenjian

    2016-01-01

    Background Pulmonary embolism has become the third most common cardiovascular disease, which can seriously harm human health. Objectives To investigate the diagnostic value of dual-source computerized tomography (CT) and perfusion imaging for peripheral pulmonary embolism. Patients and Methods Thirty-two patients with suspected pulmonary embolism underwent dual-source CT exams. To compare the ability of pulmonary embolism detection software (PED) with CT pulmonary angiography (CTPA) in determining the presence, numbers, and locations of pulmonary emboli, the subsequent images were reviewed by two radiologists using both imaging modalities. Also, the diagnostic consistency between PED and CTPA images and dual-energy pulmonary perfusion imaging (DEPI) for segmental pulmonary embolism was compared. Results CTPA images revealed 50 (7.81%) segmental and 56 (4.38%) sub-segmental pulmonary embolisms, while the PED images showed 68 (10.63%) segmental and 94 (7.34%) sub-segmental pulmonary embolisms. Thus, the detection rate on PED images for peripheral pulmonary embolism was significantly higher than that of the CTPA images (P < 0.05). There was good consistency for diagnosing segmental pulmonary embolism between PED and CTPA and DEPI (kappa = 0.85). The sensitivity and specificity of DEPI images for the diagnosis of pulmonary embolism were 91.7% and 97.5%, respectively. Conclusion PED software of dual-source CT combined with perfusion imaging can significantly improve the detection rate of peripheral pulmonary embolism. PMID:27703656

  4. Emerging diagnostic and therapeutic molecular imaging applications in vascular disease

    PubMed Central

    Eraso, Luis H; Reilly, Muredach P; Sehgal, Chandra; Mohler, Emile R

    2013-01-01

    Assessment of vascular disease has evolved from mere indirect and direct measurements of luminal stenosis to sophisticated imaging methods to depict millimeter structural changes of the vasculature. In the near future, the emergence of multimodal molecular imaging strategies may enable robust therapeutic and diagnostic (‘theragnostic’) approaches to vascular diseases that comprehensively consider structural, functional, biological and genomic characteristics of the disease in individualized risk assessment, early diagnosis and delivery of targeted interventions. This review presents a summary of recent preclinical and clinical developments in molecular imaging and theragnostic applications covering diverse atherosclerosis events such as endothelial activation, macrophage infammatory activity, plaque neovascularization and arterial thrombosis. The main focus is on molecular targets designed for imaging platforms commonly used in clinical medicine including magnetic resonance, computed tomography and positron emission tomography. A special emphasis is given to vascular ultrasound applications, considering the important role this imaging platform plays in the clinical and research practice of the vascular medicine specialty. PMID:21310769

  5. Healthcare provider and patient perspectives on diagnostic imaging investigations

    PubMed Central

    Bergh, Anne-Marie; Hoffmann, Willem A.

    2015-01-01

    Background: Much has been written about the patient-centred approach in doctor–patient consultations. Little is known about interactions and communication processes regarding healthcare providers’ and patients’ perspectives on expectations and experiences of diagnostic imaging investigations within the medical encounter. Patients journey through the health system from the point of referral to the imaging investigation itself and then to the post-imaging consultation. Aim and setting: To explore healthcare provider and patient perspectives on interaction and communication processes during diagnostic imaging investigations as part of their clinical journey through a healthcare complex. Methods: A qualitative study was conducted, with two phases of data collection. Twenty-four patients were conveniently selected at a public district hospital complex and were followed throughout their journey in the hospital system, from admission to discharge. The second phase entailed focus group interviews conducted with providers in the district hospital and adjacent academic hospital (medical officers and family physicians, nurses, radiographers, radiology consultants and registrars). Results: Two main themes guided our analysis: (1) provider perspectives; and (2) patient dispositions and reactions. Golden threads that cut across these themes are interactions and communication processes in the context of expectations, experiences of the imaging investigations and the outcomes thereof. Conclusion: Insights from this study provide a better understanding of the complexity of the processes and interactions between providers and patients during the imaging investigations conducted as part of their clinical pathway. The interactions and communication processes are provider–patient centred when a referral for a diagnostic imaging investigation is included. PMID:26245604

  6. Diagnostic value of image processing in myocardial scintigraphy

    SciTech Connect

    Cinotti, L.; Meignan, M.; Usdin, J.P.; Vasile, N.; Castaigne, A.

    1983-09-01

    The diagnostic value of stress myocardial analog scintigrams, and of five image-processing methods, was assessed by a decisional analysis in 96 patients undergoing coronary arteriography. The methods involved digitalization, nine-point binomial smoothing, background subtraction by linear interpolation, stationary filtering, and a combination of them. The difference between after-test probabilities of having the disease with a postive or a negative examination provided a discriminant index for different prevalences of the disease. Though the processing methods failed to improve the detection of a circumflex stenosis, the stationary filter significantly increased the diagnostic value for the detection of stenosis in a left anterior descending artery for a large range of prevalence, and in a right coronary artery at high prevalence. Thus, the filter seemed to provide a useful tool for enhancing the diagnostic value of myocardial scintigraphy.

  7. Diagnostic value of image processing in myocardial scintigraphy

    SciTech Connect

    Cinotti, L.; Meignan, M.; Usdin, J.P.; Vasile, N.; Castaigne, A.

    1983-09-01

    The diagnostic value of stress myocardial analog scintigrams, and of five image-processing methods, was assessed by a decisional analysis in 96 patients undergoing coronary arteriography. The methods involved digitalization, nine-point binomial smoothing, background subtraction by linear interpolation, stationary filtering, and a combination of them. The difference between after-test probabilities of having the disease with a positive or a negative examination provided a discriminant index for different prevalences of the disease. Though the processing methods failed to improve the detection of a circumflex stenosis, the stationary filter significantly increased the diagnostic value for the detection of stenosis in a left anterior descending artery for a large range of prevalence, and in a right coronary artery at high prevalence. Thus, the filter seemed to provide a useful tool for enhancing the diagnostic value of myocardial scintigraphy.

  8. Evolving imaging techniques in diagnostic strategies of pulmonary embolism.

    PubMed

    Robert-Ebadi, Helia; Le Gal, Grégoire; Righini, Marc

    2016-01-01

    Modern non invasive diagnostic strategies for pulmonary embolism (PE) rely on the sequential use of clinical probability assessment, D-dimer measurement and thoracic imaging tests. Planar ventilation/perfusion (V/Q) scintigraphy was the cornerstone for more than two decades and has now been replaced by computed tomography pulmonary angiography (CTPA). Diagnostic strategies using CTPA are very safe to rule out PE and have been well validated in large prospective management outcome studies. With the widespread use of CTPA, concerns regarding radiation and overdiagnosis of PE have paved the way for investigating new diagnostic modalities. V/Q single photon emission tomography has arisen as a highly accurate test and a potential alternative to CTPA. However, prospective management outcome studies are still lacking and are warranted before implementation in everyday clinical practice.

  9. Combining a thermal-imaging diagnostic with an existing imaging VISAR diagnostic at the National Ignition Facility (NIF)

    SciTech Connect

    Robert M. Malone; John R. Celesteb; Peter M. Celliers; Brent C. Froggeta; Robert L. Guyton; Morris I. Kaufman; Tony L. Lee; Brian J. MacGowan; Edmund W. Ng; Imants P. Reinbachs; Ronald B. Robinson; Lynn G. Seppala; Tom W. Tunnell; Phillip W. Watts

    2005-01-01

    Optical diagnostics are currently being designed to analyze high-energy density physics experiments at the National Ignition Facility (NIF). Two independent line-imaging Velocity Interferometer System for Any Reflector (VISAR) interferometers have been fielded to measure shock velocities, breakout times, and emission of targets having sizes of 1–5 mm. An 8-inch-diameter, fused silica triplet lens collects light at f/3 inside the 30-foot-diameter NIF vacuum chamber. VISAR recordings use a 659.5-nm probe laser. By adding a specially coated beam splitter to the interferometer table, light at wavelengths from 540 to 645 nm is spilt into a thermal-imaging diagnostic. Because fused silica lenses are used in the first triplet relay, the intermediate image planes for different wavelengths separate by considerable distances. A corrector lens on the interferometer table reunites these separated wavelength planes to provide a good image. Thermal imaging collects light at f/5 from a 2-mm object placed at Target Chamber Center (TCC). Streak cameras perform VISAR and thermal-imaging recording. All optical lenses are on kinematic mounts so that pointing accuracy of the optical axis may be checked. Counter-propagating laser beams (orange and red) are used to align both diagnostics. The red alignment laser is selected to be at the 50 percent reflection point of the beam splitter. This alignment laser is introduced at the recording streak cameras for both diagnostics and passes through this special beam splitter on its way into the NIF vacuum chamber.

  10. Combining a thermal-imaging diagnostic with an existing imaging VISAR diagnostic at the National Ignition Facility (NIF)

    SciTech Connect

    Malone, R; Celeste, J; Celliers, P; Frogget, B; Guyton, R L; Kaufman, M; Lee, T; MacGowan, B; Ng, E W; Reinbachs, I P; Robinson, R B; Seppala, L; Tunnell, T W; Watts, P

    2005-07-07

    Optical diagnostics are currently being designed to analyze high-energy density physics experiments at the National Ignition Facility (NIF). Two independent line-imaging Velocity Interferometer System for Any Reflector (VISAR) interferometers have been fielded to measure shock velocities, breakout times, and emission of targets having sizes of 1-5 mm. An 8-inch-diameter, fused silica triplet lens collects light at f/3 inside the 30-foot-diameter NIF vacuum chamber. VISAR recordings use a 659.5-nm probe laser. By adding a specially coated beam splitter to the interferometer table, light at wavelengths from 540 to 645 nm is spilt into a thermal-imaging diagnostic. Because fused silica lenses are used in the first triplet relay, the intermediate image planes for different wavelengths separate by considerable distances. A corrector lens on the interferometer table reunites these separated wavelength planes to provide a good image. Thermal imaging collects light at f/5 from a 2-mm object placed at Target Chamber Center (TCC). Streak cameras perform VISAR and thermal-imaging recording. All optical lenses are on kinematic mounts so that pointing accuracy of the optical axis may be checked. Counter-propagating laser beams (orange and red) are used to align both diagnostics. The red alignment laser is selected to be at the 50 percent reflection point of the beam splitter. This alignment laser is introduced at the recording streak cameras for both diagnostics and passes through this special beam splitter on its way into the NIF vacuum chamber.

  11. Combining a thermal-imaging diagnostic with an existing imaging VISAR diagnostic at the National Ignition Facility (NIF)

    NASA Astrophysics Data System (ADS)

    Malone, Robert M.; Celeste, John R.; Celliers, Peter M.; Frogget, Brent C.; Guyton, Robert L.; Kaufman, Morris I.; Lee, Tony L.; MacGowan, Brian J.; Ng, Edmund W.; Reinbachs, Imants P.; Robinson, Ronald B.; Seppala, Lynn G.; Tunnell, Thomas W.; Watts, Phillip W.

    2005-08-01

    Optical diagnostics are currently being designed to analyze high-energy density physics experiments at the National Ignition Facility (NIF). Two independent line-imaging Velocity Interferometer System for Any Reflector (VISAR) interferometers have been fielded to measure shock velocities, breakout times, and emission of targets having sizes of 1-5 mm. An 8-inch-diameter, fused silica triplet lens collects light at f/3 inside the 30-foot-diameter NIF vacuum chamber. VISAR recordings use a 659.5-nm probe laser. By adding a specially coated beam splitter to the interferometer table, light at wavelengths from 540 to 645 nm is spilt into a thermal-imaging diagnostic. Because fused silica lenses are used in the first triplet relay, the intermediate image planes for different wavelengths separate by considerable distances. A corrector lens on the interferometer table reunites these separated wavelength planes to provide a good image. Thermal imaging collects light at f/5 from a 2-mm object placed at Target Chamber Center (TCC). Streak cameras perform VISAR and thermal-imaging recording. All optical lenses are on kinematic mounts so that pointing accuracy of the optical axis may be checked. Counter-propagating laser beams (orange and red) are used to align both diagnostics. The red alignment laser is selected to be at the 50 percent reflection point of the beam splitter. This alignment laser is introduced at the recording streak cameras for both diagnostics and passes through this special beam splitter on its way into the NIF vacuum chamber.

  12. Current profile reconstruction using electron temperature imaging diagnostics

    SciTech Connect

    Tritz, K.; Stutman, D.; Delgado-Aparicio, L.F.; Finkenthal, M.; Pacella, D.; Kaita, R.; Stratton, B.; Sabbagh, S.

    2004-10-01

    Flux surface shape information can be used to constrain the current profile for reconstruction of the plasma equilibrium. One method of inferring flux surface shape relies on plasma x-ray emission; however, deviations from the flux surfaces due to impurity and density asymmetries complicate the interpretation. Electron isotherm surfaces should correspond well to the plasma flux surfaces, and equilibrium constraint modeling using this isotherm information constrains the current profile. The KFIT code is used to assess the profile uncertainty and to optimize the number, location and SNR required for the Te detectors. As Te imaging detectors we consider tangentially viewing, vertically spaced, linear gas electron multiplier arrays operated in pulse height analysis (PHA) mode and multifoil soft x-ray arrays. Isoflux coordinate sets provided by T{sub e} measurements offer a strong constraint on the equilibrium reconstruction in both a stacked horizontal array configuration and a crossed horizontal and vertical beam system, with q{sub 0} determined to within {+-}4%. The required SNR can be provided with either PHA or multicolor diagnostic techniques, though the multicolor system requires {approx}x4 better statistics for comparable final errors.

  13. [The Will Rogers phenomenon and its impact on imaging diagnostics].

    PubMed

    Golder, W A

    2009-04-01

    The Will Rogers phenomenon is a possible cause of systematic distortions in the results of clinical studies, which can be produced if stage migration occurs during a disease. The term refers to the apparent paradox which is observed when an element is changed from one set to another and the average values of both sets are altered in the same way. The effect is due to the prerequisite that the numerical value of the element being moved is placed between the mean values of both groups. In medicine, this phenomenon is a consequence of the evolution of staging procedures and may be source of misleading statistics for survival in cancer. Both advanced pathological assessment and modern imaging techniques may be involved. The wrong conclusions are induced by comparing the effects of treatment in contemporary patient groups, which profit from extensive diagnostic procedures, to those of historical controls. Treatise informs about the history of the term and illustrates its effects by numerical examples and clinical data. Finally, a model computation based on current PET/CT figures is offered.

  14. Reliability of whole slide images as a diagnostic modality for renal allograft biopsies.

    PubMed

    Jen, Kuang-Yu; Olson, Jean L; Brodsky, Sergey; Zhou, Xin J; Nadasdy, Tibor; Laszik, Zoltan G

    2013-05-01

    The use of digital whole slide images (WSI) in the field of pathology has become feasible for routine diagnostic purposes and has become more prevalent in recent years. This type of technology offers many advantages but must show the same degree of diagnostic reliability as conventional glass slides. Several studies have examined this issue in various settings and indicate that WSI are a reliable method for diagnostic pathology. Since transplant pathology is a highly specialized field that requires not only accurate but rapid diagnostic evaluation of biopsy materials, this field may greatly benefit from the use of WSI. In this study, we assessed the reliability of using WSI compared to conventional glass slides in renal allograft biopsies. We examined morphologic features and diagnostic categories defined by the Banff 07 Classification of Renal Allograft Pathology as well as additional morphologic features not included in this classification scheme. We found that intraobserver scores, when comparing the use of glass slides versus WSI, showed substantial agreement for both morphologic features (κ = 0.68) and acute rejection diagnostic categories (κ = 0.74). Furthermore, interobserver reliability was comparable for morphologic features (κ = 0.44 [glass] vs 0.42 [WSI]) and acute rejection diagnostic categories (κ = 0.49 [glass] vs 0.51 [WSI]). These data indicate that WSI are as reliable as glass slides for the evaluation of renal allograft biopsies.

  15. Imaging VISAR diagnostic for the National Ignition Facility (NIF)

    SciTech Connect

    Malone, R M; Bower, J R; Bradley, D K; Capelle, G A; Celeste, J R; Celliers, P M; Collins, G W; Eckart, M J; Eggert, J H; Frogget, B C; Guyton, R L; Hicks, D G; Kaufman, M I; MacGowan, B J; Montelongo, S; Ng, E W; Robinson, R B; Tunnell, T W; Watts, P W; Zapata, P G

    2004-08-30

    The National Ignition Facility (NIF) requires diagnostics to analyze high-energy density physics experiments. A VISAR (Velocity Interferometry System for Any Reflector) diagnostic has been designed to measure shock velocities, shock breakout times, and shock emission of targets with sizes from 1 to 5 mm. An 8-inch-diameter fused silica triplet lens collects light at f/3 inside the 30-foot-diameter vacuum chamber. The optical relay sends the image out an equatorial port, through a 2-inch-thick vacuum window, and into two interferometers. A 60-kW VISAR probe laser operates at 659.5 nm with variable pulse width. Special coatings on the mirrors and cutoff filters are used to reject the NIF drive laser wavelengths and to pass a band of wavelengths for VISAR, passive shock breakout light, or thermal imaging light (bypassing the interferometers). The first triplet can be no closer than 500 mm from the target chamber center and is protected from debris by a blast window that is replaced after every event. The front end of the optical relay can be temporarily removed from the equatorial port, allowing other experimenters to use that port. A unique resolution pattern has been designed to validate the VISAR diagnostic before each use. All optical lenses are on kinematic mounts so that the pointing accuracy of the optical axis can be checked. Seven CCD cameras monitor the diagnostic alignment.

  16. Imaging VISAR diagnostic for the National Ignition Facility (NIF)

    NASA Astrophysics Data System (ADS)

    Malone, Robert M.; Bower, John R.; Bradley, David K.; Capelle, Gene A.; Celeste, John R.; Celliers, Peter M.; Collins, Gilbert W.; Eckart, Mark J.; Eggert, Jon H.; Frogget, Brent C.; Guyton, Robert L.; Hicks, Damien G.; Kaufman, Morris I.; MacGowan, Brian J.; Montelongo, Samuel; Ng, Edmund W.; Robinson, Ronald B.; Tunnell, Thomas W.; Watts, Phillip W.; Zapata, Paul G.

    2005-03-01

    The National Ignition Facility (NIF) requires diagnostics to analyze high-energy density physics experiments. A VISAR (Velocity Interferometry System for Any Reflector) diagnostic has been designed to measure shock velocities, shock breakout times, and shock emission of targets with sizes from 1 to 5 mm. An 8-inch-diameter fused silica triplet lens collects light at f/3 inside the 30-foot-diameter vacuum chamber. The optical relay sends the image out an equatorial port, through a 2-inch-thick vacuum window, and into two interferometers. A 60-kW VISAR probe laser operates at 659.5 nm with variable pulse width. Special coatings on the mirrors and cutoff filters are used to reject the NIF drive laser wavelengths and to pass a band of wavelengths for VISAR, passive shock breakout light, or thermal imaging light (bypassing the interferometers). The first triplet can be no closer than 500 mm from the target chamber center and is protected from debris by a blast window that is replaced after every event. The front end of the optical relay can be temporarily removed from the equatorial port, allowing other experimenters to use that port. A unique resolution pattern has been designed to validate the VISAR diagnostic before each use. All optical lenses are on kinematic mounts so that the pointing accuracy of the optical axis can be checked. Seven CCD cameras monitor the diagnostic alignment.

  17. Comparing IKONOS and Landsat 7 Images

    NASA Technical Reports Server (NTRS)

    Blonski, Slawomir

    2002-01-01

    This work is a continuation of the simulations presented at the previous workshop.INformation is presented on the following: 20 IKONOS images compared with 10 Landsat 7 ETM+VNIR images acquired on the same days. Comparisons are based on simulations of the Landsat 7 images from the IKONOS data. IKONOS and Landsat 7 images used in simulations are on a similar processing level with radiometric correction, georeferenced with cubic-convolution resampling, and UTM projection with WGS-84 datum.

  18. Diagnostic Imaging of Canine Hepatobiliary Affections: A Review

    PubMed Central

    Kumar, Vijay; Kumar, Adarsh; Varshney, A. C.; Tyagi, S. P.; Kanwar, M. S.; Sharma, S. K.

    2012-01-01

    Hepatic disease is often treatable and has a predictable prognosis when a definitive diagnosis is made. The aim of clinicopathological evaluation of hepatobiliary affections is to identify and characterize hepatic damage and dysfunction, identify possible primary causes of secondary liver disease, differentiate causes of icterus, evaluate potential anaesthetic risks, assess prognosis and response to xenobiotics, and monitor response to therapy. This paper describes the different diagnostic methods and imaging techniques employed in diagnosis of hepatobiliary affections in dogs. Besides reviewing the significant clinical manifestations and imaging structural abnormalities in diagnostic approach to different hepatic affections, it also depicts radiographic, ultrasonographic, and wherever applicable, the laparoscopic characterization of different hepatic affections and target lesions encountered in clinical cases presented in the Teaching Veterinary Clinical Complex, COVAS, Palampur in the year 2007-2008. PMID:22577609

  19. Assessing the Risks for Modern Diagnostic Ultrasound Imaging

    NASA Astrophysics Data System (ADS)

    William, Jr.

    1998-05-01

    Some 35 years after Paul-Jacques and Pierre Curie discovered piezoelectricity, ultrasonic imaging was developed by Paul Langevin. During this work, ultrasonic energy was observed to have a detrimental biological effect. These observations were confirmed a decade later by R. W. Wood and A. L. Loomis. It was not until the early 1950s that ultrasonic exposure conditions were controlled and specified so that studies could focus on the mechanisms by which ultrasound influenced biological materials. In the late 1940s, pioneering work was initiated to image the human body by ultrasonic techniques. These engineers and physicians were aware of the deleterious ultrasound effects at sufficiently high levels; this endeavored them to keep the exposure levels reasonably low. Over the past three decades, diagnostic ultrasound has become a sophisticated technology. Yet, our understanding of the potential risks has not changed appreciably. It is very encouraging that human injury has never been attributed to clinical practice of diagnostic ultrasound.

  20. Optical Imaging Techniques for Point-of-care Diagnostics

    PubMed Central

    Zhu, Hongying; Isikman, Serhan O.; Mudanyali, Onur; Greenbaum, Alon; Ozcan, Aydogan

    2012-01-01

    Improving the access to effective and affordable healthcare has long been a global endeavor. In this quest, the development of cost-effective and easy-to-use medical testing equipment that enable rapid and accurate diagnosis is essential to reduce the time and costs associated with healthcare services. To this end, point-of-care (POC) diagnostics plays a crucial role in healthcare delivery in both the developed and developing countries by bringing medical testing to patients, or to sites near patients. As the diagnosis of a wide range of diseases, including various types of cancers and many endemics relies on optical techniques, numerous compact and cost-effective optical imaging platforms have been developed in recent years for use at the POC. Here, we review the state-of-the-art optical imaging techniques that can have significant impact on global health by facilitating effective and affordable POC diagnostics. PMID:23044793

  1. Functional infrared imaging in medicine: a quantitative diagnostic approach.

    PubMed

    Merla, A; Romani, G L

    2006-01-01

    The role and the potentialities of high-resolution infrared thermography, combined to bio-heat modelling, have been largely described in the last years in a wide variety of biomedical applications. Quantitative assessment over time of the cutaneous temperature and/or of other biomedical parameters related to the temperature (e.g., cutaneous blood flow, thermal inertia, sympathetic skin response) allows for a better and more complete understanding and description of functional processes involved and/or altered in presence of ailment and interfering with the regular cutaneous thermoregulation. Such an approach to thermal medical imaging requires both new methodologies and tools, like diagnostic paradigms, appropriate software for data analysis and, even, a completely new way to look at data processing. In this paper, some of the studies recently made in our laboratory are presented and described, with the general intent of introducing the reader to these innovative methods to obtain quantitative diagnostic tools based on thermal imaging.

  2. Diagnostic imaging and biopsy pathways following abnormal screen-film and digital screening mammography

    PubMed Central

    Hubbard, Rebecca A.; Zhu, Weiwei; Horblyuk, Ruslan; Karliner, Leah; Sprague, Brian L.; Henderson, Louise; Lee, David; Onega, Tracy; Buist, Diana SM.; Sweet, Alison

    2013-01-01

    Objective The transition from screen-film to digital mammography may have altered diagnostic evaluation of women following a positive screening examination. This study compared use and timeliness of diagnostic imaging and biopsy for women screened with screen-film or digital mammography. Materials and Methods Data were from 35,321 positive screening mammograms on 32,087 women aged 40–89 years, from 22 Breast Cancer Surveillance Consortium facilities in 2005–2008. Diagnostic pathways were classified by their inclusion of diagnostic mammography, ultrasound, magnetic resonance imaging (MRI), and biopsy. We compared time to resolution and frequency of diagnostic pathways by patient characteristics, screening exam modality, and radiology facility. Between-facility differences were evaluated by computing the proportion of mammograms receiving follow-up with a particular pathway for each facility and examining variation in these proportions across facilities. Multinomial logistic regression adjusting for age, calendar year, and facility compared odds of follow-up with each pathway. Results The median time to resolution of a positive screening mammogram was 10 days. Compared to screen-film mammograms, digital mammograms were more frequently followed by only a single diagnostic mammogram (46% vs. 36%). Pathways following digital screening mammography were also less likely to include biopsy (16% vs. 20%). However, in adjusted analyses most differences were not statistically significant (p = 0.857 for mammography only; p = 0.03 for biopsy). Substantial variability in diagnostic pathway frequency was seen across facilities. For instance, the frequency of evaluation with diagnostic mammography alone ranged from 23% to 55% across facilities. Conclusion Differences in evaluation of positive digital and screen-film screening mammograms were minor, and appeared to be largely attributable to substantial variation between radiology facilities. To guide health systems in their

  3. Diagnostic imaging and biopsy pathways following abnormal screen-film and digital screening mammography.

    PubMed

    Hubbard, Rebecca A; Zhu, Weiwei; Horblyuk, Ruslan; Karliner, Leah; Sprague, Brian L; Henderson, Louise; Lee, David; Onega, Tracy; Buist, Diana S M; Sweet, Alison

    2013-04-01

    The transition from screen-film to digital mammography may have altered diagnostic evaluation of women following a positive screening examination. This study compared the use and timeliness of diagnostic imaging and biopsy for women screened with screen-film or digital mammography. Data were obtained from 35,321 positive screening mammograms on 32,087 women aged 40-89 years, from 22 breast cancer surveillance consortium facilities in 2005-2008. Diagnostic pathways were classified by their inclusion of diagnostic mammography, ultrasound, magnetic resonance imaging, and biopsy. We compared time to resolution and frequency of diagnostic pathways by patient characteristics, screening exam modality, and radiology facility. Between-facility differences were evaluated by computing the proportion of mammograms receiving follow-up with a particular pathway for each facility and examining variation in these proportions across facilities. Multinomial logistic regression adjusting for age, calendar year, and facility compared odds of follow-up with each pathway. The median time to resolution of a positive screening mammogram was 10 days. Compared to screen-film mammograms, digital mammograms were more frequently followed by only a single diagnostic mammogram (46 vs. 36 %). Pathways following digital screening mammography were also less likely to include biopsy (16 vs. 20 %). However, in adjusted analyses, most differences were not statistically significant (p = 0.857 for mammography only; p = 0.03 for biopsy). Substantial variability in diagnostic pathway frequency was seen across facilities. For instance, the frequency of evaluation with diagnostic mammography alone ranged from 23 to 55 % across facilities. Differences in evaluation of positive digital and screen-film screening mammograms were minor, and appeared to be largely attributable to substantial variation between radiology facilities. To guide health systems in their efforts to eliminate practices that do not

  4. Diagnostic Imaging of Pulmonary Thromboembolism by Multidetector-row CT

    PubMed Central

    2010-01-01

    For diagnosis of pulmonary thromboembolism, multidetector-row computed tomography (CT) is a minimally invasive imaging technique that can be performed rapidly with high sensitivity and specificity, and has been increasingly employed as the imaging modality of first choice for this disease. Since deep vein thrombosis in the legs, which is important as a thrombus source, can be evaluated immediately after the diagnosis of pulmonary thromboembolism, this diagnostic method is considered to provide important information when deciding on a comprehensive therapeutic strategy for this disease. PMID:23555409

  5. Imaging Live Bee Brains using Minimally-Invasive Diagnostic Radioentomology

    PubMed Central

    Greco, Mark K; Tong, Jenna; Soleimani, Manucher; Bell, Duncan; Schäfer, Marc O

    2012-01-01

    The sensitivity of the honey bee, Apis mellifera L. (Hymeonoptera: Apidae), brain volume and density to behavior (plasticity) makes it a great model for exploring the interactions between experience, behavior, and brain structure. Plasticity in the adult bee brain has been demonstrated in previous experiments. This experiment was conducted to identify the potentials and limitations of MicroCT (micro computed tomograpy) scanning “live” bees as a more comprehensive, non-invasive method for brain morphology and physiology. Bench-top and synchrotron MicroCT were used to scan live bees. For improved tissue differentiation, bees were fed and injected with radiographic contrast. Images of optic lobes, ocelli, antennal lobes, and mushroom bodies were visualized in 2D and 3D rendering modes. Scanning of live bees (for the first time) enabled minimally-invasive imaging of physiological processes such as passage of contrast from gut to haemolymph, and preliminary brain perfusion studies. The use of microCT scanning for studying insects (collectively termed ‘diagnostic radioentomology’, or DR) is increasing. Our results indicate that it is feasible to observe plasticity of the honey bee brain in vivo using diagnostic radioentomology, and that progressive, real-time observations of these changes can be followed in individual live bees. Limitations of live bee scanning, such as movement errors and poor tissue differentiation, were identified; however, there is great potential for in-vivo, non-invasive diagnostic radioentomology imaging of the honey bee for brain morphology and physiology. PMID:23421752

  6. Towards real-time medical diagnostics using hyperspectral imaging technology

    NASA Astrophysics Data System (ADS)

    Bjorgan, Asgeir; Randeberg, Lise L.

    2015-07-01

    Hyperspectral imaging provides non-contact, high resolution spectral images which has a substantial diagnostic potential. This can be used for e.g. diagnosis and early detection of arthritis in finger joints. Processing speed is currently a limitation for clinical use of the technique. A real-time system for analysis and visualization using GPU processing and threaded CPU processing is presented. Images showing blood oxygenation, blood volume fraction and vessel enhanced images are among the data calculated in real-time. This study shows the potential of real-time processing in this context. A combination of the processing modules will be used in detection of arthritic finger joints from hyperspectral reflectance and transmittance data.

  7. The clinician's guide to diagnostic imaging: Cost-effective pathways. Second edition

    SciTech Connect

    Grossman, Z.D.; Chew, F.S.; Ellis, D.A.; Brigham, S.C.

    1987-01-01

    The authors developed a cost-effective approach to imaging studies, based on initial selection of an exam that best addresses the specific clinical problem and obviates the need for additional diagnostic tests. Tightly reasoned arguments compare available imaging options with respect to diagnostic yield, feasibility, risk, and cost. To aid the clinician in making cost comparisons, each paper of the Second Edition lists the dollar cost of relevant imaging studies. The Second Edition has been thoroughly revised to reflect the important advances in diagnostic imaging of the past three years, highlighting CT's expanding role in thoracic and abdominal problems, magnetic resonance imaging as a spectacular diagnostic tool for the central nervous system, and the clinical application of many newly-developed radiopharmaceuticals. New chapters cover breast cancer screening, acute spinal trauma, search for primary cancer of unknown origin, acute anuria, blunt chest trauma, new onset seizures, and spinal cord compression from metastases. Other papers have been rewritten for greater clarity and to incorporate new techniques, like dipyridamole stress testing. A glossary and an introduction define and explain the capabilities and limitations of current techniques.

  8. Current and Prospective Use of Musculoskeletal Diagnostic Ultrasound Imaging at Chiropractic Teaching Institutions: A Worldwide Survey of Diagnostic Imaging Staff.

    PubMed

    Henderson, Rogan E A; Walker, Bruce F; Young, Kenneth J

    2017-03-01

    The purpose of this study was to survey the use of musculoskeletal diagnostic ultrasound imaging (MSK-DUSI) at chiropractic educational programs worldwide and to elicit opinions of academic diagnostic imaging staff of its prospective use at their teaching institutions. An electronic questionnaire was delivered in 2014 using SurveyMonkey and notifications were disseminated by e-mail to 127 diagnostic imaging staff at chiropractic programs worldwide. The questionnaire consisted of 27 items using multiple-choice, Likert-type, and open-ended questions. Descriptive statistics were used for basic demographic data and the results of the numerical scales used in each item. Fifty-nine respondents (46.5%) from 24 (24/41) chiropractic programs returned questionnaires. The reported use of MSK-DUSI at chiropractic programs is low (n = 5/24); however, respondents from 9 institutions stated that it is planned to be implemented. Few respondents stated they had formal MSK-DUSI qualifications (4/59); however, 7 respondents stated they were in the process of becoming certified. Most respondents expressed an interest in the prospect of incorporating MSK-DUSI at their chiropractic program. Sixty-five percent stated that chiropractic programs should provide MSK-DUSI training to chiropractic students, and 75% of respondents stated that chiropractic programs should be providing accredited postgraduate MSK-DUSI courses. The current use of MSK-DUSI among chiropractic programs that responded to this survey is low. The opinions of diagnostic imaging staff who responded suggest a positive attitude to its use and possible growth in its use if foundational work, including gaining funding, accreditation, and acceptance of within the scope of chiropractic practice, is undertaken.

  9. Precision imaging-its impact on image quality and diagnostic confidence in breast ultrasound examinations.

    PubMed

    Safina, Alfiya; Lau, Louisa; Brennan, Patrick; Mello-Thoms, Claudia; Kench, Peter; Ryan, Elaine; McEntee, Mark; Rickard, Mary

    2015-10-01

    To determine the effect of noise-reducing innovation-precision imaging (PI)-on image quality and diagnostic efficacy in breast ultrasound. The study, which assessed four levels of PI from zero to three, consisted of two parts: image quality assessment and diagnostic efficacy evaluation. For the first part, 247 sets of ultrasound images displayed at each PI level were evaluated by 6 experienced breast imaging observers, by rating image quality using visual grading analysis on a 1-4 scale. For the diagnostic efficacy part 51 breast lesions were displayed at each PI level and scored 1-6 to generate a receiver operating characteristic (ROC) curve. These images were evaluated by radiologists and sonographers. Analyses were performed using non-parametric Friedman and Wilcoxon signed rank tests and a multireader multicase methodology. Statistically, higher scores of image quality were observed with increased levels of PI than with the zero setting (p < 0.001). The ROC analysis did not demonstrate any significant change in diagnostic efficacy, with mean scores for all observers being 0.79, 0.80, 0.81 and 0.81 for settings zero, one, two and three, respectively. This study suggested a perceived improvement in image quality with increasing levels of PI; however, no changes in diagnostic efficacy were noted. The importance of looking at the impact of new imaging technologies in a multifaceted way is emphasized. To our knowledge, this is the first article investigating the impact of the PI algorithm on ultrasound image quality and breast lesion characterization.

  10. MITOCHONDRIAL REDOX IMAGING FOR CANCER DIAGNOSTIC AND THERAPEUTIC STUDIES

    PubMed Central

    LI, LIN Z.; XU, HE N.; RANJI, MAHSA; NIOKA, SHOKO; CHANCE, BRITTON

    2015-01-01

    Mitochondrial redox states provide important information about energy-linked biological processes and signaling events in tissues for various disease phenotypes including cancer. The redox scanning method developed at the Chance laboratory about 30 years ago has allowed 3D high-resolution (~ 50 × 50 × 10 μm3) imaging of mitochondrial redox state in tissue on the basis of the fluorescence of NADH (reduced nicotinamide adenine dinucleotide) and Fp (oxidized flavoproteins including flavin adenine dinucleotide, i.e., FAD). In this review, we illustrate its basic principles, recent technical developments, and biomedical applications to cancer diagnostic and therapeutic studies in small animal models. Recently developed calibration procedures for the redox imaging using reference standards allow quantification of nominal NADH and Fp concentrations, and the concentration-based redox ratios, e.g., Fp/(Fp+NADH) and NADH/(Fp+NADH) in tissues. This calibration facilitates the comparison of redox imaging results acquired for different metabolic states at different times and/or with different instrumental settings. A redox imager using a CCD detector has been developed to acquire 3D images faster and with a higher in-plane resolution down to 10 μm. Ex vivo imaging and in vivo imaging of tissue mitochondrial redox status have been demonstrated with the CCD imager. Applications of tissue redox imaging in small animal cancer models include metabolic imaging of glioma and myc-induced mouse mammary tumors, predicting the metastatic potentials of human melanoma and breast cancer mouse xenografts, differentiating precancerous and normal tissues, and monitoring the tumor treatment response to photodynamic therapy. Possible future directions for the development of redox imaging are also discussed. PMID:26015810

  11. Technology in radiology: advances in diagnostic imaging & therapeutics.

    PubMed

    Stern, S M

    1993-01-01

    Nearly 100 years from its birth, radiology continues to grow as though still in adolescence. Although some radiologic technologies have matured more than others, new applications and techniques appear regularly in the literature. Radiology has evolved from purely diagnostic devices to interventional technologies. New contrast agents in MRI, X ray and ultrasound enable physicians to make diagnoses and plan therapies with greater precision than ever before. Techniques are less and less invasive. Advances in computer technology have given supercomputer-like power to high-end nuclear medicine and MRI systems. Imaging systems in most modalities are now designed with upgrades in mind instead of "planned obsolescence." Companies routinely upgrade software and other facets of their products, sometimes at no additional charge to existing customers. Hospitals, radiology groups and imaging centers will face increasing demands to justify what they do according to patient outcomes and management criteria. Did images make the diagnosis or confirm it? Did the images determine optimal treatment strategies or confirm which strategies might be appropriate? Third-party payers, especially the government, will view radiology in those terms. The diagnostic imaging and therapy systems of today require increasingly sophisticated technical support for maintenance and repair. Hospitals, radiology groups and imaging centers will have to determine the most economic and effective ways to guarantee equipment up-time. Borrowing from the automotive industry, some radiology manufacturers have devised transtelephonic software systems to facilitate remote troubleshooting. To ensure their fiscal viability, hospitals continue to acquire new imaging and therapy technologies for competitive and access-to-services reasons.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Strategic planning for radiology: opening an outpatient diagnostic imaging center.

    PubMed

    Leepson, Evan

    2003-01-01

    Launching a new diagnostic imaging center involves very specific requirements and roadmaps, including five major areas of change that have a direct impact on planning: Imaging and communication technology Finances and reimbursement Ownership structure of imaging entities Critical workforce shortages Imaging is moving outside radiology First, planning must focus on the strategic level of any organization, whether it is a multi-national corporation or a six-person radiology group. Think of all organizations as a triangle with three horizontal levels: strategic, managerial and operational. The strategic level of decision-making is at the top of the triangle, and here is where planning must take place. For strategic planning to work, there must be focused time and energy spent on this activity, usually away from the reading room and imaging center. There are five planning strategies, which must have the explicit goal of developing and growing the imaging center. The five strategies are: Clinical and quality issues, Governance and administration, Technology, Relationships, Marketing and business development. The best way to plan and implement these strategies is to create work groups of radiologists, technologists, and administrative and support staff. Once the group agrees on the strategy and tactic, it takes responsibility for implementation. Embarking on the launch of a new outpatient diagnostic imaging center is no small undertaking, and anyone who has struggled with such an endeavor can readily attest to the associated challenges and benefits. Success depends on many things, and one of the most important factors relates to the amount of time and the quality of effort spent on strategic planning at the outset. Neglecting or skimping on this phase may lead to unforeseen obstacles that could potentially derail the project.

  13. Diagnostic imaging of acute abdominal pain in adults.

    PubMed

    Cartwright, Sarah L; Knudson, Mark P

    2015-04-01

    Acute abdominal pain is a common presentation in the outpatient setting and can represent conditions ranging from benign to life-threatening. If the patient history, physical examination, and laboratory testing do not identify an underlying cause of pain and if serious pathology remains a clinical concern, diagnostic imaging is indicated. The American College of Radiology has developed clinical guidelines, the Appropriateness Criteria, based on the location of abdominal pain to help physicians choose the most appropriate imaging study. Ultrasonography is the initial imaging test of choice for patients presenting with right upper quadrant pain. Computed tomography (CT) is recommended for evaluating right or left lower quadrant pain. Conventional radiography has limited diagnostic value in the assessment of most patients with abdominal pain. The widespread use of CT raises concerns about patient exposure to ionizing radiation. Strategies to reduce exposure are currently being studied, such as using ultrasonography as an initial study for suspected appendicitis before obtaining CT and using low-dose CT rather than standard-dose CT. Magnetic resonance imaging is another emerging technique for the evaluation of abdominal pain that avoids ionizing radiation.

  14. Raman spectroscopy and imaging: promising optical diagnostic tools in pediatrics.

    PubMed

    Beleites, C; Bonifacio, A; Codrich, D; Krafft, C; Sergo, V

    2013-01-01

    This review focuses on the use of Raman spectroscopy, an analytical technique based on the inelastic scattering of harmless laser light with biological tissues, as an innovative diagnostic tool in pediatrics. After a brief introduction to explain the fundamental concepts behind Raman spectroscopy and imaging, a short summary is given of the most important and common issues arising when handling spectral data with multivariate statistics. Then, the most relevant papers in which Raman spectroscopy or imaging has been applied with diagnostic purposes to pediatric patients are reviewed, and grouped according to the type of pathology: neoplastic, inflammatory, allergic, malformative as well as other kinds. Raman spectroscopy has been used both in vivo, mostly using optical fibers for tissue illumination, as well as on ex vivo tissue sections in a microscopic imaging approach defined as "spectral histopathology". According to the results reported so far, this technique showed a huge potential for mini- or non-invasive real-time, bedside and intra-operatory diagnosis, as well as for an ex vivo imaging tool in support to pathologists. Despite many studies are limited by the small sample size, this technique is extremely promising in terms of sensitivity and specificity.

  15. Choice of diagnostic and therapeutic imaging in periodontics and implantology.

    PubMed

    Chakrapani, Swarna; Sirisha, K; Srilalitha, Anumadi; Srinivas, Moogala

    2013-11-01

    Imaging forms an integral component for diagnosis of dental and in specific periodontal diseases. To date, intra-oral radiographic techniques are the main non-invasive diagnostic aids for the detection and assessment of internal changes in mineralized periodontal tissues like alveolar bone. These analog radiographic techniques suffer from inherent limitations like: Two dimensional projection, magnification, distortion, superimposition and misrepresentation of anatomic structures. The evolution of novel imaging modalities, namely cone beam computed tomography, tuned aperture CT empowered dental researchers to visualize the periodontium three dimensionally. This improves interpretation of structural and biophysical changes, ensures densitometric assessments of dentoalveolar structures including variations in alveolar bone density, and peri-implant bone healing more precisely. This detailed review, highlights current leading edge concepts, envisions a wide range of imaging modalities which pave the way for better understanding and early intervention of periodontal diseases.

  16. [Image diagnostic of the retina with fundus cameras].

    PubMed

    Koschmieder, Ingo; Müller, Lothar

    2007-01-01

    Imaging of the retina of the human eye is an essential aid for medical diagnosis. The technical realization of photos of the ocular fundus is not trivial because of the optical properties of the eye. Established devices to obtain images are so called fundus cameras with digital documentation capabilities. New procedures do not need the use of pupils enlarging measures at the patient and work with infrared illumination. The quality of the diagnostic findings depends on the one hand fundamentally on the lay-out of the optical design of the fundus camera. On the other hand there are limitations caused by the eye itself which is always a part of the beam path. Both impacts define the attainable results. Special applications deal with the stereoscopic imaging of the retina or with spectral reflection characteristics.

  17. 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.

  18. The clinician's guide to diagnostic imaging: Cost effective pathways

    SciTech Connect

    Grossman, Z.D.; Chew, F.S.; Ellis, D.A.; Brigham, S.C.

    1987-01-01

    This book presents logical, step-by-step imaging sequences for 47 medical, surgical, and pediatric problems. Topics considered include breast cancer screening, acute spinal trauma, search for primary cancer of unknown origin, acute anuria, blunt chest trauma, new onset seizures, and spinal cord compression from metastases. Other chapters have been rewritten to enhance the clarity of presentation and to incorporate new techniques such as magnetic resonance imaging, dipyridamole stress testing, and single photon emission computed tomography. The book highlights the expanding role of CT in evaluation of thoracic and abdominal problems, the emergence of magnetic resonance imaging as a vital diagnostic tool for the central nervous system, and the clinical utility of many newly developed radiopharmaceuticals.

  19. Diagnostic Accuracy of Clinical Examination and Imaging Findings for Identifying Subacromial Pain

    PubMed Central

    2016-01-01

    Background The diagnosis of subacromial pathology is limited by the poor accuracy of clinical tests for specific pathologies. The aim of this study was to estimate the diagnostic accuracy of clinical examination and imaging features for identifying subacromial pain (SAP) defined by a positive response to diagnostic injection, and to evaluate the influence of imaging findings on the clinical diagnosis of SAP. Methods and Findings In a prospective, diagnostic accuracy design, 208 consecutive patients presenting to their primary healthcare practitioner for the first time with a new episode of shoulder pain were recruited. All participants underwent a standardized clinical examination, shoulder x-ray series and diagnostic ultrasound scan. Results were compared with the response to a diagnostic block of xylocaineTM injected into the SAB under ultrasound guidance using ≥80% post-injection reduction in pain intensity as the positive anaesthetic response (PAR) criterion. Diagnostic accuracy statistics were calculated for combinations of clinical and imaging variables demonstrating the highest likelihood of a PAR. A PAR was reported by 34% of participants. In participants with no loss of passive external rotation, combinations of three clinical variables (anterior shoulder pain, strain injury, absence of symptoms at end-range external rotation (in abduction)) demonstrated 100% specificity for a PAR when all three were positive (LR+ infinity; 95%CI 2.9, infinity). A full-thickness supraspinatus tear on ultrasound increased the likelihood of a PAR irrespective of age (specificity 98% (95%CI 94, 100); LR+ 6.2; 95% CI 1.5, 25.7)). Imaging did not improve the ability to rule-out a PAR. Conclusion Combinations of clinical examination findings and a full-thickness supraspinatus tear on ultrasound scan can help confirm, but not exclude, the presence of subacromial pain. Other imaging findings were of limited value for diagnosing SAP. PMID:27936246

  20. Visualization, imaging and new preclinical diagnostics in radiation oncology

    PubMed Central

    2014-01-01

    Innovative strategies in cancer radiotherapy are stimulated by the growing knowledge on cellular and molecular tumor biology, tumor pathophysiology, and tumor microenvironment. In terms of tumor diagnostics and therapy monitoring, the reliable delineation of tumor boundaries and the assessment of tumor heterogeneity are increasingly complemented by the non-invasive characterization of functional and molecular processes, moving preclinical and clinical imaging from solely assessing tumor morphology towards the visualization of physiological and pathophysiological processes. Functional and molecular imaging techniques allow for the non-invasive characterization of tissues in vivo, using different modalities, including computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, positron emission tomography (PET) and optical imaging (OI). With novel therapeutic concepts combining optimized radiotherapy with molecularly targeted agents focusing on tumor cell proliferation, angiogenesis, and cell death, the non-invasive assessment of tumor microcirculation and tissue water diffusion, together with strategies for imaging the mechanisms of cellular injury and repair is of particular interest. Characterizing the tumor microenvironment prior to and in response to irradiation will help to optimize the outcome of radiotherapy. These novel concepts of personalized multi-modal cancer therapy require careful pre-treatment stratification as well as a timely and efficient therapy monitoring to maximize patient benefit on an individual basis. Functional and molecular imaging techniques are key in this regard to open novel opportunities for exploring and understanding the underlying mechanisms with the perspective to optimize therapeutic concepts and translate them into a personalized form of radiotherapy in the near future. PMID:24387195

  1. Physical therapist practice and the role of diagnostic imaging.

    PubMed

    Boyles, Robert E; Gorman, Ira; Pinto, Daniel; Ross, Michael D

    2011-11-01

    For healthcare providers involved in the management of patients with musculoskeletal disorders, the ability to order diagnostic imaging is a beneficial adjunct to screening for medical referral and differential diagnosis. A trial of conservative treatment, such as physical therapy, is often recommended prior to the use of imaging in many treatment guidelines for the management of musculoskeletal conditions. In the United States, physical therapists are becoming more autonomous and can practice some degree of direct access in 48 states and Washington, DC. Referral for imaging privileges could increase the effectiveness and efficiency of healthcare delivery, particularly in combination with direct access management. This clinical commentary proposes that, given the American Physical Therapy Association's goal to have physical therapists as primary care musculoskeletal specialists of choice, it would be beneficial for physical therapists to have imaging privileges in their practice. The purpose of this commentary is 3-fold: (1) to make a case for the use of imaging privileges by physical therapists, using a historical perspective; (2) to discuss the barriers preventing physical therapists from having this privilege; and (3) to offer suggestions on strategies and guidelines to facilitate the appropriate inclusion of referral for imaging privileges in physical therapist practice. J Orthop Sports Phys Ther 2011;41(11):829-837. doi:10.2519/jospt.2011.3556.

  2. Australian per caput dose from diagnostic imaging and nuclear medicine.

    PubMed

    Hayton, A; Wallace, A; Marks, P; Edmonds, K; Tingey, D; Johnston, P

    2013-10-01

    The largest man-made contributor to the ionising radiation dose to the Australian population is from diagnostic imaging and nuclear medicine. The last estimation of this dose was made in 2004 (1.3 mSv), this paper describes a recent re-evaluation of this dose to reflect the changes in imaging trends and technology. The estimation was calculated by summing the dose from five modalities, computed tomography (CT), general radiography/fluoroscopy, interventional procedures, mammography and nuclear medicine. Estimates were made using Australian frequency data and dose data from a range of Australian and international sources of average effective dose values. The ionising radiation dose to the Australian population in 2010 from diagnostic imaging and nuclear medicine is estimated to be 1.7 mSv (1.11 mSv CT, 0.30 mSv general radiography/fluoroscopy, 0.17 mSv interventional procedures, 0.03 mSv mammography and 0.10 mSv nuclear medicine). This exceeds the estimate of 1.5 mSv per person from natural background and cosmic radiation.

  3. Comparative guide to emerging diagnostic tools for large commercial HVAC systems

    SciTech Connect

    Friedman, Hannah; Piette, Mary Ann

    2001-05-01

    This guide compares emerging diagnostic software tools that aid detection and diagnosis of operational problems for large HVAC systems. We have evaluated six tools for use with energy management control system (EMCS) or other monitoring data. The diagnostic tools summarize relevant performance metrics, display plots for manual analysis, and perform automated diagnostic procedures. Our comparative analysis presents nine summary tables with supporting explanatory text and includes sample diagnostic screens for each tool.

  4. [Positron emission tomography: diagnostic imaging on a molecular level].

    PubMed

    Allemann, K; Wyss, M; Wergin, M; Bley, C Rohrer; Ametamay, S; Bruehlmeier, M; Kaser-Hotz, B

    2004-08-01

    In human medicine positron emission tomography (PET) is a modern diagnostic imaging method. In the present paper we outline the physical principles of PET and give an overview over the main clinic fields where PET is being used, such as neurology, cardiology and oncology. Moreover, we present a current project in veterinary medicine (in collaboration with the Paul Scherrer Institute and the University Hospital Zurich), where a hypoxia tracer is applied to dogs and cats suffering from spontaneous tumors. Finally new developments in the field of PET were discussed.

  5. [Diagnostic imaging--CT, dynamic CT, and others].

    PubMed

    Kurosawa, Hajime

    2011-10-01

    Technical advances have raised computed tomography(CT) as a strong diagnostic tool of clinical imaging. Emphysematous changes can be quantitatively analyzed as low attenuation area which correlated with diffusion capacity, quality of life, and nutritional states, but not so much with forced expiratory volume in one second. With co-analyzing airway wall thickness, those are possibly useful to understand phenotypes. Dynamics of airway during breathing can be visualized by dynamic CT such as electron-beam CT. Dynamic airway narrowing is a representative feature in emphysematous lung.

  6. General equations for optimal selection of diagnostic image acquisition parameters in clinical X-ray imaging.

    PubMed

    Zheng, Xiaoming

    2017-08-18

    The purpose of this work was to examine the effects of relationship functions between diagnostic image quality and radiation dose on the governing equations for image acquisition parameter variations in X-ray imaging. Various equations were derived for the optimal selection of peak kilovoltage (kVp) and exposure parameter (milliAmpere second, mAs) in computed tomography (CT), computed radiography (CR), and direct digital radiography. Logistic, logarithmic, and linear functions were employed to establish the relationship between radiation dose and diagnostic image quality. The radiation dose to the patient, as a function of image acquisition parameters (kVp, mAs) and patient size (d), was used in radiation dose and image quality optimization. Both logistic and logarithmic functions resulted in the same governing equation for optimal selection of image acquisition parameters using a dose efficiency index. For image quality as a linear function of radiation dose, the same governing equation was derived from the linear relationship. The general equations should be used in guiding clinical X-ray imaging through optimal selection of image acquisition parameters. The radiation dose to the patient could be reduced from current levels in medical X-ray imaging.

  7. Multiphoton microscopy as a diagnostic imaging modality for lung cancer

    NASA Astrophysics Data System (ADS)

    Pavlova, Ina; Hume, Kelly R.; Yazinski, Stephanie A.; Peters, Rachel M.; Weiss, Robert S.; Webb, Watt W.

    2010-02-01

    Lung cancer is the leading killer among all cancers for both men and women in the US, and is associated with one of the lowest 5-year survival rates. Current diagnostic techniques, such as histopathological assessment of tissue obtained by computed tomography guided biopsies, have limited accuracy, especially for small lesions. Early diagnosis of lung cancer can be improved by introducing a real-time, optical guidance method based on the in vivo application of multiphoton microscopy (MPM). In particular, we hypothesize that MPM imaging of living lung tissue based on twophoton excited intrinsic fluorescence and second harmonic generation can provide sufficient morphologic and spectroscopic information to distinguish between normal and diseased lung tissue. Here, we used an experimental approach based on MPM with multichannel fluorescence detection for initial discovery that MPM spectral imaging could differentiate between normal and neoplastic lung in ex vivo samples from a murine model of lung cancer. Current results indicate that MPM imaging can directly distinguish normal and neoplastic lung tissues based on their distinct morphologies and fluorescence emission properties in non-processed lung tissue. Moreover, we found initial indication that MPM imaging differentiates between normal alveolar tissue, inflammatory foci, and lung neoplasms. Our long-term goal is to apply results from ex vivo lung specimens to aid in the development of multiphoton endoscopy for in vivo imaging of lung abnormalities in various animal models, and ultimately for the diagnosis of human lung cancer.

  8. Imaging system for hypervelocity dust injection diagnostic on NSTX

    SciTech Connect

    Dorf, L. A.; Roquemore, A. L.; Wurden, G. A.; Ticos, C. M.; Wang Zhehui

    2006-10-15

    The novel hypervelocity dust injection diagnostic will facilitate our understanding of basic aspects of dust-plasma interaction and magnetic field topology in fusion plasma devices, by observing 'comet tails' associated with the injected micron-size dust particles. A single projection of the tail onto an image plane will not provide sufficient information; therefore, we plan to use two views, with intensified DiCam-Pro cameras on two NSTX ports. Each camera can furnish up to five overlaying sequential images with gate times greater than 3 ns and 1280x1024 pixel resolution. A coherent fiber bundle with 1500x1200 fibers will relay the image from an imaging lens installed directly on the port to the camera optics. The lens receives light from the outer portion of the NSTX cross section and focuses a 1 cm tail onto at least 60 fibers for adequate resolution. The estimated number of photons received by the camera indicates signal-to-noise ratios of 10{sup 2}-10{sup 4}, with the use of a 10 nm bandwidth filter. The imaging system with one camera was successfully tested on NSTX in 2005. Photographing lithium pellets yielded bright and distinctive pictures of the tails nearly aligned with B lines. We also observed that the bright 'filaments' - plasma cords with high density and temperature - are present in both top and bottom portions of the machine.

  9. Stress Myocardial Perfusion Imaging in the Emergency Department - New Techniques for Speed and Diagnostic Accuracy

    PubMed Central

    Harrison, Sheri D; Harrison, Mark A; Duvall, W Lane

    2012-01-01

    Emergency room evaluations of patients presenting with chest pain continue to rise, and these evaluations which often include cardiac imaging, are an increasing area of resource utilization in the current health system. Myocardial perfusion imaging from the emergency department remains a vital component of the diagnosis or exclusion of coronary artery disease as the etiology of chest pain. Recent advances in camera technology, and changes to the imaging protocols have allowed MPI to become a more efficient way of providing this diagnostic information. Compared with conventional SPECT, new high-efficiency CZT cameras provide a 3-5 fold increase in photon sensitivity, 1.65-fold improvement in energy resolution and a 1.7-2.5-fold increase in spatial resolution. With stress-only imaging, rest images are eliminated if stress images are normal, as they provide no additional prognostic or diagnostic value and cancelling the rest images would shorten the length of the test which is of particular importance to the ED population. The rapid but accurate triage of patients in an ED CPU is essential to their care, and stress-only imaging and new CZT cameras allow for shorter test time, lower radiation doses and lower costs while demonstrating good clinical outcomes. These changes to nuclear stress testing can allow for faster throughput of patients through the emergency department while providing a safe and efficient evaluation of chest pain. PMID:22708910

  10. Advanced synchronous luminescence imaging for chemical and medical diagnostics

    DOEpatents

    Vo-Dinh, Tuan

    2006-09-05

    A diagnostic method and associated system includes the steps of exposing at least one sample location with excitation radiation through a single optical waveguide or a single optical waveguide bundle, wherein the sample emits emission radiation in response to the excitation radiation. The same single optical waveguide or the single optical waveguide bundle receives at least a portion of the emission radiation from the sample, thus providing co-registration of the excitation radiation and the emission radiation. The wavelength of the excitation radiation and emission radiation is synchronously scanned to produce a spectrum upon which an image can be formed. An increased emission signal is generated by the enhanced overlap of the excitation and emission focal volumes provided by co-registration of the excitation and emission signals thus increasing the sensitivity as well as decreasing the exposure time necessary to obtain an image.

  11. [Development of DICOM image viewing software for efficient image reading and evaluation of distributed server system for diagnostic environment].

    PubMed

    Ishikawa, K

    2000-12-01

    To construct an efficient diagnostic environment using computer displays, the author investigated the time of network transmission using clinical images. In our hospital, we introduced optical-fiber 100Base-Fx Ethernet connections between 22 HIS-segments and one RIS-segment. Although Ethernet architecture is inexpensive, the speed of image transmission becomes 2371 KB/sec. (4.6 CT-slice/sec.) in the RIS-segment and 996 KB/sec. (1.9 CT-slice/sec.) from the RIS-segment to HIS-segments. Because one examination is transmitted in one minute, it does not disturb image reading. Otherwise, a distributed server system using inexpensive personal computers helps in constructing an efficient system. This investigation showed that commercially based Digital Imaging and Communications in Medicine(DICOM) servers and RSNA Central Test Node servers are not so different in transmission speed. The author programmed and developed DICOM transmission and viewing software for Macintosh computers. This viewer includes two inventions, dynamic tiling window system (DTWS) and window binding mode(WBM). On DTWS, windows, tiles, and images are independent objects, which are movable and resizable. The tile-matrix is changeable by mouse dragging, which realizes suitable tile rectangles for wide-low or narrow-high images. The arranging window tool prevents windows from scattering. Using WBM, any operation affects each window similarly. This means that the relationship of compared images is always equivalent. DTWS and WBM contribute greatly to a filmless diagnostic environment.

  12. Whole slide imaging diagnostic concordance with light microscopy for breast needle biopsies.

    PubMed

    Campbell, W Scott; Hinrichs, Steven H; Lele, Subodh M; Baker, John J; Lazenby, Audrey J; Talmon, Geoffrey A; Smith, Lynette M; West, William W

    2014-08-01

    This study investigated the diagnostic accuracy of whole slide imaging (WSI) in breast needle biopsy diagnosis in comparison with standard light microscopy (LM). The study examined the effects of image capture magnification and computer monitor quality on diagnostic concordance of WSI and LM. Four pathologists rendered diagnoses using WSI to examine 85 breast biopsies (92 parts; 786 slides) consisting of benign and malignant cases. Each WSI case was evaluated using images captured at either ×20 or ×40 magnifications and viewed using a Digital Imaging and Communication in Medicine (DICOM) grade, color-calibrated monitor or a standard, desktop liquid-crystal display (LCD) monitor. For each combination, the WSI result was compared with the original, LM diagnosis. The overall concordance rate observed between WSI and LM was 97.1% (95% confidence intervals [CI]: 94.3%-98.5%). After a washout period, all cases were reviewed a second time by each pathologist after using LM, and the second LM diagnosis was compared with the WSI diagnosis rendered by the same pathologist. Intraobserver concordance between WSI and LM was 95.4% (95% CI: 92.2%-97.4%). The second LM diagnoses were also compared with the original LM diagnoses, and the observed interobserver LM concordance rate was 97.3% (95% CI: 93.1%-99.0%). The study data demonstrated that breast needle biopsy diagnoses rendered by WSI were equivalent to diagnoses rendered by LM. No diagnostic differences were detected between the underlying viewing system parameters of monitor quality and image capture resolution. The results of this study demonstrated that WSI can be effectively used in subspecialty diagnostic cases where a minimum amount of tissue is available.

  13. Patient and family impact of pediatric genitourinary diagnostic imaging tests.

    PubMed

    Nelson, Caleb P; Chow, Jeanne S; Rosoklija, Ilina; Ziniel, Sonja; Routh, Jonathan C; Cilento, Bartley G

    2012-10-01

    The impact of diagnostic genitourinary imaging on patients and families is poorly understood. We measured patient and family reaction to commonly performed genitourinary imaging studies using a standardized measurement tool. We surveyed families undergoing genitourinary imaging (renal ultrasound, voiding cystourethrography, radionuclide cystogram, static renal scintigraphy and diuretic renal scintigraphy) using a Likert scaled 11-item survey to assess impact across 4 domains (pain, anxiety, time, satisfaction). Survey scores were analyzed using ANOVA and linear regression. A total of 263 families were surveyed (61 renal ultrasound, 52 voiding cystourethrogram, 55 radionuclide cystogram, 47 mercaptoacetyltriglycine dynamic renal scintigraphy, 48 dimercaptosuccinic acid static renal scintigraphy). Mean patient age was 2.1 years old. Of the patients 45% were male and 77% were white. Patient age, gender and prior genitourinary imaging experience varied by study type. Study type was significantly associated with total and weighted scores on the genitourinary imaging survey (both p <0.0001). Renal ultrasound was scored as better and mercaptoacetyltriglycine dynamic renal scintigraphy was worse than voiding cystourethrogram, radionuclide cystogram and dimercaptosuccinic acid static renal scintigraphy, which did not differ from each other. Other factors associated with worse total scores included patient age 1 to 3 years (p <0.001) and nonwhite race (p = 0.04). Gender, prior testing history, wait time and parent education were not associated with total scores. In the multivariate model renal ultrasound remained the best and mercaptoacetyltriglycine dynamic renal scintigraphy the worst (p <0.0001). In a direct comparison dimercaptosuccinic acid static renal scintigraphy and voiding cystourethrogram total scores did not differ (p = 0.59). There were significant differences among genitourinary imaging studies regarding the patient/family experience, but there was no overall

  14. Meeting the Needs for Radiation Protection: Diagnostic Imaging.

    PubMed

    Frush, Donald P

    2017-02-01

    Radiation and potential risk during medical imaging is one of the foremost issues for the imaging community. Because of this, there are growing demands for accountability, including appropriate use of ionizing radiation in diagnostic and image-guided procedures. Factors contributing to this include increasing use of medical imaging; increased scrutiny (from awareness to alarm) by patients/caregivers and the public over radiation risk; and mounting calls for accountability from regulatory, accrediting, healthcare coverage (e.g., Centers for Medicare and Medicaid Services), and advisory agencies and organizations as well as industry (e.g., NEMA XR-29, Standard Attributes on CT Equipment Related to Dose Optimization and Management). Current challenges include debates over uncertainty with risks with low-level radiation; lack of fully developed and targeted products for diagnostic imaging and radiation dose monitoring; lack of resources for and clarity surrounding dose monitoring programs; inconsistencies across and between practices for design, implementation and audit of dose monitoring programs; lack of interdisciplinary programs for radiation protection of patients; potential shortages in personnel for these and other consensus efforts; and training concerns as well as inconsistencies for competencies throughout medical providers' careers for radiation protection of patients. Medical care providers are currently in a purgatory between quality- and value-based imaging paradigms, a state that has yet to mature to reward this move to quality-based performance. There are also deficits in radiation expertise personnel in medicine. For example, health physics academic programs and graduates have recently declined, and medical physics residency openings are currently at a third of the number of graduates. However, leveraging solutions to the medical needs will require money and resources, beyond personnel alone. Energy and capital will need to be directed to

  15. Optical systems for point-of-care diagnostic instrumentation: analysis of imaging performance and cost.

    PubMed

    Pierce, Mark C; Weigum, Shannon E; Jaslove, Jacob M; Richards-Kortum, Rebecca; Tkaczyk, Tomasz S

    2014-01-01

    One of the key elements in point-of-care (POC) diagnostic test instrumentation is the optical system required for signal detection and/or imaging. Many tests which use fluorescence, absorbance, or colorimetric optical signals are under development for management of infectious diseases in resource limited settings, where the overall size and cost of the device is of critical importance. At present, high-performance lenses are expensive to fabricate and difficult to obtain commercially, presenting barriers for developers of in vitro POC tests or microscopic image-based diagnostics. We recently described a compact "hybrid" objective lens incorporating both glass and plastic optical elements, with a numerical aperture of 1.0 and field-of-view of 250 μm. This design concept may potentially enable mass-production of high-performance, low-cost optical systems which can be easily incorporated in the readout path of existing and emerging POC diagnostic assays. In this paper, we evaluate the biological imaging performance of these lens systems in three broad POC diagnostic application areas; (1) bright field microscopy of histopathology slides, (2) cytologic examination of blood smears, and (3) immunofluorescence imaging. We also break down the fabrication costs and draw comparisons with other miniature optical systems. The hybrid lenses provided images with quality comparable to conventional microscopy, enabling examination of neoplastic pathology and infectious parasites including malaria and cryptosporidium. We describe how these components can be produced at below $10 per unit in full-scale production quantities, making these systems well suited for use within POC diagnostic instrumentation.

  16. Optical systems for point-of-care diagnostic instrumentation: analysis of imaging performance and cost

    PubMed Central

    Pierce, Mark C.; Weigum, Shannon E.; Jaslove, Jacob M.; Richards-Kortum, Rebecca; Tkaczyk, Tomasz S.

    2013-01-01

    One of the key elements in point-of-care (POC) diagnostic test instrumentation is the optical system required for signal detection and / or imaging. Many tests which use fluorescence, absorbance, or colorimetric optical signals are under development for management of infectious diseases in resource limited settings, where the overall size and cost of the device is of critical importance. At present, high-performance lenses are expensive to fabricate and difficult to obtain commercially, presenting barriers for developers of in vitro POC tests or microscopic image-based diagnostics. We recently described a compact “hybrid” objective lens incorporating both glass and plastic optical elements, with a numerical aperture of 1.0 and field-of-view of 250 m. This design concept may potentially enable mass-production of high-performance, low-cost optical systems which can be easily incorporated in the readout path of existing and emerging POC diagnostic assays. In this paper, we evaluate the biological imaging performance of these lens systems in three broad POC diagnostic application areas; (1) bright field microscopy of histopathology slides, (2) cytologic examination of blood smears, and (3) immunofluorescence imaging. We also break down the fabrication costs and draw comparisons with other miniature optical systems. The hybrid lenses provided images with quality comparable to conventional microscopy, enabling examination of neoplastic pathology and infectious parasites including malaria and cryptosporidium. We describe how these components can be produced at below $10 per unit in full-scale production quantities, making these systems well suited for use within POC diagnostic instrumentation. PMID:24097204

  17. [Sonography of the teat of cattle, sheep and goats in comparison with other methods of diagnostic imaging--a review].

    PubMed

    Franz, S; Hofmann-Parisot, M; Gumpenberger, M

    2001-01-01

    Beside the clinical examination of udder/teat imaging methods e.g. sonography, radiography and endoscopy allow diagnosis. This publication will give a summary of currently used and potentially usable methods of diagnostic imaging applied to the teat. Advantages and disadvantages of the several methods were compared--as quoted in literature and completed by own experiences.

  18. Comparing the performance of different ultrasonic images enhancement for speckle noise reduction in ultrasound images using techniques: a preference study

    NASA Astrophysics Data System (ADS)

    Rana, Md. Shohel; Sarker, Kaushik; Bhuiyan, Touhid; Hassan, Md. Maruf

    2017-06-01

    Diagnostic ultrasound (US) is an important tool in today's sophisticated medical diagnostics. Nearly every medical discipline benefits itself from this relatively inexpensive method that provides a view of the inner organs of the human body without exposing the patient to any harmful radiations. Medical diagnostic images are usually corrupted by noise during their acquisition and most of the noise is speckle noise. To solve this problem, instead of using adaptive filters which are widely used, No-Local Means based filters have been used to de-noise the images. Ultrasound images of four organs such as Abdomen, Ortho, Liver, Kidney, Brest and Prostrate of a Human body have been used and applied comparative analysis study to find out the output. These images were taken from Siemens SONOLINE G60 S System and the output was compared by matrices like SNR, RMSE, PSNR IMGQ and SSIM. The significance and compared results were shown in a tabular format.

  19. Nanoparticles: a boon to drug delivery, therapeutics, diagnostics and imaging.

    PubMed

    Parveen, Suphiya; Misra, Ranjita; Sahoo, Sanjeeb K

    2012-02-01

    Drug delivery is an interdisciplinary and independent field of research and is gaining the attention of pharmaceutical researchers, medical doctors and industry. A safe and targeted drug delivery could improve the performance of some classic medicines already on the market, and moreover, will have implications for the development and success of new therapeutic strategies such as anticancer drug delivery, peptide and protein delivery and gene therapy. In the last decade, several drug-delivery technologies have emerged and a fascinating part of this field is the development of nanoscale drug delivery devices. Nanoparticles (NPs) have been developed as an important strategy to deliver conventional drugs, recombinant proteins, vaccines and more recently, nucleotides. NPs and other colloidal drug-delivery systems modify the kinetics, body distribution and drug release of an associated drug. This review article focuses on the potential of nanotechnology in medicine and discusses different nanoparticulate drug-delivery systems including polymeric NPs, ceramic NPs, magnetic NPs, polymeric micelles and dendrimers as well as their applications in therapeutics, diagnostics and imaging. This comprehensive review focuses on different nanoparticulate drug-delivery systems including polymeric NPs, ceramic NPs, magnetic NPs, polymeric micelles and dendrimers as well as their applications in therapeutics, diagnostics and imaging. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Magnetic nanoparticles in magnetic resonance imaging and diagnostics.

    PubMed

    Rümenapp, Christine; Gleich, Bernhard; Haase, Axel

    2012-05-01

    Magnetic nanoparticles are useful as contrast agents for magnetic resonance imaging (MRI). Paramagnetic contrast agents have been used for a long time, but more recently superparamagnetic iron oxide nanoparticles (SPIOs) have been discovered to influence MRI contrast as well. In contrast to paramagnetic contrast agents, SPIOs can be functionalized and size-tailored in order to adapt to various kinds of soft tissues. Although both types of contrast agents have a inducible magnetization, their mechanisms of influence on spin-spin and spin-lattice relaxation of protons are different. A special emphasis on the basic magnetism of nanoparticles and their structures as well as on the principle of nuclear magnetic resonance is made. Examples of different contrast-enhanced magnetic resonance images are given. The potential use of magnetic nanoparticles as diagnostic tracers is explored. Additionally, SPIOs can be used in diagnostic magnetic resonance, since the spin relaxation time of water protons differs, whether magnetic nanoparticles are bound to a target or not.

  1. Gas puff imaging diagnostic on NSTX-U

    NASA Astrophysics Data System (ADS)

    Zweben, S. J.; Scotti, F.; Stotler, D. L.; Diallo, A.; Mandell, N.; Terry, J. L.; Han, W.

    2016-10-01

    The first results and plans for the gas puff imaging (GPI) diagnostic on NSTX-U will be described. The GPI optical efficiency has been improved by about × 10 using a new fiber bundle and interference filter, and the new optics has a zoom lens which can potentially resolve turbulence below the ion gyroradius scale. Experiments are planned to study high-k edge turbulence, correlations of edge turbulence with the SOL heat flux width, and the trigger mechanism of the L-H transition. A second fast camera is planned to view the GPI gas cloud from across the machine, which can potentially measure the field line pitch by simultaneously viewing individual field-aligned blob filaments in the radial vs. poloidal (GPI) and toroidal vs. poloidal (second camera) directions. An incoming collaboration from MIT will bring a 9 × 10 pixel APD-based detector array from Alcator C-Mod to NSTX-U, initially for faster and more sensitive imaging of the existing GPI gas puff. New results and further diagnostic plans will be described. This work was supported by USDOE Contracts #DE-AC02-09CH11466, DE-SC0014264, and DE-AC52-07NA27344.

  2. Diagnostic Method of Diabetes Based on Support Vector Machine and Tongue Images

    PubMed Central

    Hu, Xiaojuan; Chen, Qingguang; Tu, Liping; Huang, Jingbin; Cui, Ji

    2017-01-01

    Objective. The purpose of this research is to develop a diagnostic method of diabetes based on standardized tongue image using support vector machine (SVM). Methods. Tongue images of 296 diabetic subjects and 531 nondiabetic subjects were collected by the TDA-1 digital tongue instrument. Tongue body and tongue coating were separated by the division-merging method and chrominance-threshold method. With extracted color and texture features of the tongue image as input variables, the diagnostic model of diabetes with SVM was trained. After optimizing the combination of SVM kernel parameters and input variables, the influences of the combinations on the model were analyzed. Results. After normalizing parameters of tongue images, the accuracy rate of diabetes predication was increased from 77.83% to 78.77%. The accuracy rate and area under curve (AUC) were not reduced after reducing the dimensions of tongue features with principal component analysis (PCA), while substantially saving the training time. During the training for selecting SVM parameters by genetic algorithm (GA), the accuracy rate of cross-validation was grown from 72% or so to 83.06%. Finally, we compare with several state-of-the-art algorithms, and experimental results show that our algorithm has the best predictive accuracy. Conclusions. The diagnostic method of diabetes on the basis of tongue images in Traditional Chinese Medicine (TCM) is of great value, indicating the feasibility of digitalized tongue diagnosis. PMID:28133611

  3. Diagnostic Method of Diabetes Based on Support Vector Machine and Tongue Images.

    PubMed

    Zhang, Jianfeng; Xu, Jiatuo; Hu, Xiaojuan; Chen, Qingguang; Tu, Liping; Huang, Jingbin; Cui, Ji

    2017-01-01

    Objective. The purpose of this research is to develop a diagnostic method of diabetes based on standardized tongue image using support vector machine (SVM). Methods. Tongue images of 296 diabetic subjects and 531 nondiabetic subjects were collected by the TDA-1 digital tongue instrument. Tongue body and tongue coating were separated by the division-merging method and chrominance-threshold method. With extracted color and texture features of the tongue image as input variables, the diagnostic model of diabetes with SVM was trained. After optimizing the combination of SVM kernel parameters and input variables, the influences of the combinations on the model were analyzed. Results. After normalizing parameters of tongue images, the accuracy rate of diabetes predication was increased from 77.83% to 78.77%. The accuracy rate and area under curve (AUC) were not reduced after reducing the dimensions of tongue features with principal component analysis (PCA), while substantially saving the training time. During the training for selecting SVM parameters by genetic algorithm (GA), the accuracy rate of cross-validation was grown from 72% or so to 83.06%. Finally, we compare with several state-of-the-art algorithms, and experimental results show that our algorithm has the best predictive accuracy. Conclusions. The diagnostic method of diabetes on the basis of tongue images in Traditional Chinese Medicine (TCM) is of great value, indicating the feasibility of digitalized tongue diagnosis.

  4. A comparative study of electrical probe techniques for plasma diagnostics

    NASA Technical Reports Server (NTRS)

    Szuszczewicz, E. P.

    1972-01-01

    Techniques for using electrical probes for plasma diagnostics are reviewed. Specific consideration is given to the simple Langmuir probe, the symmetric double probe of Johnson and Malter, the variable-area probe of Fetz and Oeschsner, and a floating probe technique. The advantages and disadvantages of each technique are discussed.

  5. Image processing methods and architectures in diagnostic pathology.

    PubMed

    Bueno, Gloria; Déniz, Oscar; Salido, Jesús; Rojo, Marcial García

    2009-01-01

    Grid technology has enabled the clustering and the efficient and secure access to and interaction among a wide variety of geographically distributed resources such as: supercomputers, storage systems, data sources, instruments and special devices and services. Their main applications include large-scale computational and data intensive problems in science and engineering. General grid structures and methodologies for both software and hardware in image analysis for virtual tissue-based diagnosis has been considered in this paper. This methods are focus on the user level middleware. The article describes the distributed programming system developed by the authors for virtual slide analysis in diagnostic pathology. The system supports different image analysis operations commonly done in anatomical pathology and it takes into account secured aspects and specialized infrastructures with high level services designed to meet application requirements. Grids are likely to have a deep impact on health related applications, and therefore they seem to be suitable for tissue-based diagnosis too. The implemented system is a joint application that mixes both Web and Grid Service Architecture around a distributed architecture for image processing. It has shown to be a successful solution to analyze a big and heterogeneous group of histological images under architecture of massively parallel processors using message passing and non-shared memory.

  6. Lensfree holographic imaging for on-chip cytometry and diagnostics.

    PubMed

    Seo, Sungkyu; Su, Ting-Wei; Tseng, Derek K; Erlinger, Anthony; Ozcan, Aydogan

    2009-03-21

    We experimentally illustrate a lensfree holographic imaging platform to perform on-chip cytometry. By controlling the spatial coherence of the illumination source, we record a 2D holographic diffraction pattern of each cell or micro-particle on a chip using a high resolution sensor array that has approximately 2 microm pixel size. The recorded holographic image is then processed by using a custom developed decision algorithm for matching the detected hologram texture to existing library images for on-chip characterization and counting of a heterogeneous solution of interest. The holographic diffraction signature of any microscopic object is significantly different from the classical diffraction pattern of the same object. It improves the signal to noise ratio and the signature uniformity of the cell patterns; and also exhibits much better sensitivity for on-chip imaging of weakly scattering phase objects such as small bacteria or cells. We verify significantly improved performance of this holographic on-chip cytometry approach by automatically characterizing heterogeneous solutions of red blood cells, yeast cells, E. coli and various sized micro-particles without the use of any lenses or microscope objectives. This lensless on-chip holography platform will especially be useful for point-of-care cytometry and diagnostics applications involving e.g., infectious diseases such as HIV or malaria.

  7. Thermoacoustic imaging and spectroscopy for enhanced cancer diagnostics

    NASA Astrophysics Data System (ADS)

    Bauer, Daniel Ryan

    Early detection of cancer is paramount for improved patient survival. This dissertation presents work developing imaging techniques to improve cancer diagnostics and detection utilizing light and microwave induced thermoacoustic imaging. In the second chapter, the well-established pre-clinical mouse window chamber model is interfaced with simultaneously acquired high-resolution pulse echo (PE) ultrasound and photoacoustic (PA) imaging. Co-registered PE and PA imaging, coupled with developed image segmentation algorithms, are used to quantitatively track and monitor the size, shape, heterogeneity, and neovasculature of the tumor microenvironment during a month long study. Average volumetric growth was 5.35 mm3/day, which correlated well with two dimensional results from fluorescent imaging (R = 0.97, p < 0.01). Spectroscopic PA imaging is also employed to probe the assumed oxygenation status of the tumor vasculature. The window chamber model combined with high-resolution PE and PA imaging could form a powerful testbed for characterizing cancers and evaluating new contrast and therapeutic agents. The third chapter utilizes a clinical ultrasound array to facilitate fast volumetric spectroscopic PA imaging to detect and discriminate endogenous absorbers (i.e. oxy/deoxygenated hemoglobin) as well as exogenous PA contrast agents (i.e. gold nanorods, fluorophores). In vivo spatiotemporal tracking of administered gold nanorods is presented, with the contrast agent augmenting the PA signal 18 dB. Furthermore, through the use of spectral unmixing algorithms, the relative concentrations of multiple endogenous and exogenous co-localized absorbers were reconstructed in tumor bearing mice. The concentration of Alexaflour647 was calculated to increase nearly 20 dB in the center of a prostate tumor after a tail-vein injection of the contrast agent. Additionally, after direct subcutaneous injections of two different gold nanorods into a breast tumor, the concentration of each

  8. Diagnostic imaging of psoriatic arthritis. Part II: magnetic resonance imaging and ultrasonography

    PubMed Central

    Pracoń, Grzegorz

    2016-01-01

    Plain radiography reveals specific, yet late changes of advanced psoriatic arthritis. Early inflammatory changes are seen both on magnetic resonance imaging and ultrasound within peripheral joints (arthritis, synovitis), tendons sheaths (tenosynovitis, tendovaginitis) and entheses (enthesitis, enthesopathy). In addition, magnetic resonance imaging enables the assessment of inflammatory features in the sacroiliac joints (sacroiliitis), and the spine (spondylitis). In this article, we review current opinions on the diagnostics of some selective, and distinctive features of psoriatic arthritis concerning magnetic resonance imaging and ultrasound and present some hypotheses on psoriatic arthritis etiopathogenesis, which have been studied with the use of magnetic resonance imaging. The following elements of the psoriatic arthritis are discussed: enthesitis, extracapsular inflammation, dactylitis, distal interphalangeal joint and nail disease, and the ability of magnetic resonance imaging to differentiate undifferentiated arthritis, the value of whole-body magnetic resonance imaging and dynamic contrast-enhanced magnetic resonance imaging. PMID:27446601

  9. Diagnostic imaging of psoriatic arthritis. Part II: magnetic resonance imaging and ultrasonography.

    PubMed

    Sudoł-Szopińska, Iwona; Pracoń, Grzegorz

    2016-06-01

    Plain radiography reveals specific, yet late changes of advanced psoriatic arthritis. Early inflammatory changes are seen both on magnetic resonance imaging and ultrasound within peripheral joints (arthritis, synovitis), tendons sheaths (tenosynovitis, tendovaginitis) and entheses (enthesitis, enthesopathy). In addition, magnetic resonance imaging enables the assessment of inflammatory features in the sacroiliac joints (sacroiliitis), and the spine (spondylitis). In this article, we review current opinions on the diagnostics of some selective, and distinctive features of psoriatic arthritis concerning magnetic resonance imaging and ultrasound and present some hypotheses on psoriatic arthritis etiopathogenesis, which have been studied with the use of magnetic resonance imaging. The following elements of the psoriatic arthritis are discussed: enthesitis, extracapsular inflammation, dactylitis, distal interphalangeal joint and nail disease, and the ability of magnetic resonance imaging to differentiate undifferentiated arthritis, the value of whole-body magnetic resonance imaging and dynamic contrast-enhanced magnetic resonance imaging.

  10. Image quality and diagnostic performance of free-breathing diffusion-weighted imaging for hepatocellular carcinoma.

    PubMed

    Takayama, Yukihisa; Nishie, Akihiro; Asayama, Yoshiki; Ishigami, Kousei; Kakihara, Daisuke; Ushijima, Yasuhiro; Fujita, Nobuhiro; Shirabe, Ken; Takemura, Atsushi; Honda, Hiroshi

    2017-05-18

    To retrospectively evaluate the diagnostic performance of free-breathing diffusion-weighted imaging (FB-DWI) with modified imaging parameter settings for detecting hepatocellular carcinomas (HCCs). Fifty-one patients at risk for HCC were scanned with both FB-DWI and respiratory-triggered DWI with the navigator echo respiratory-triggering technique (RT-DWI). Qualitatively, the sharpness of the liver contour, the image noise and the chemical shift artifacts on each DWI with b-values of 1000 s/mm(2) were independently evaluated by three radiologists using 4-point scoring. We compared the image quality scores of each observer between the two DWI methods, using the Wilcoxon signed-rank test. Quantitatively, we compared the signal-to-noise ratios (SNRs) of the liver parenchyma and lesion-to-nonlesion contrast-to-noise ratios (CNRs) after measuring the signal intensity on each DWI with a b-factor of 1000 s/mm(2). The average SNRs and CNRs between the two DWI methods were compared by the paired t-test. The detectability of HCC on each DWI was also analyzed by three radiologists. The detectability provided by the two DWI methods was compared using McNemar's test. For all observers, the averaged image quality scores of FB-DWI were: Sharpness of the liver contour [observer (Obs)-1, 3.08 ± 0.81; Obs-2, 2.98 ± 0.73; Obs-3, 3.54 ± 0.75], those of the distortion (Obs-1, 2.94 ± 0.50; Obs-2, 2.71 ± 0.70; Obs-3, 3.27 ± 0.53), and the chemical shift artifacts (Obs-1, 3.38 ± 0.60; Obs-2, 3.15 ± 1.07; Obs-3, 3.21 ± 0.85). The averaged image quality scores of RT-DWI were: Sharpness of the liver contour (Obs-1, 2.33 ± 0.65; Obs-2, 2.37 ± 0.74; Obs-3, 2.75 ± 0.81), distortion (Obs-1, 2.81 ± 0.56; Obs-2, 2.25 ± 0.74; Obs-3, 2.96 ± 0.71), and the chemical shift artifacts (Obs-1, 2.92 ± 0.59; Obs-2, 2.21 ± 0.85; Obs-3, 2.77 ± 1.08). All image quality scores of FB-DWI were significantly higher than those of RT-DWI (P < 0.05). The average SNR of the normal liver parenchyma by

  11. Digital diagnostic imaging with a comprehensive PACS: hypothetical economic evaluation at a large community hospital.

    PubMed

    Warburton, R N; Fisher, P D; Nosil, J; Brauer, G W; Lawrence, W J; Ritchie, G W

    1990-05-01

    Since 1983, the 422-bed Victoria General Hospital (VGH) and Siemens Electric Limited have been piloting the implementation of digital medical imaging, including digital acquisition of diagnostic images, in British Columbia. Although full PACS is not yet in place at VGH, experience to date has been used to project annual cost figures (including capital replacement) for a fully digital department. The resulting economic evaluation has been labeled hypothetical to emphasize that some key cost components were estimated rather than observed; this paper presents updated cost figures based on recent revisions to proposed departmental equipment configuration. Compared with conventional diagnostic imaging, digital imaging appears to raise overall annual costs at VGH by nearly $0.7 million, (Canadian currency) or 11.6%; this is more favorable than the previous results, which indicated extra annual costs of $1 million (16.9%). Sensitivity analysis still indicates that all reasonable changes in the underlying assumptions result in higher costs for digital imaging than for conventional imaging. Digital imaging appears likely to offer lower radiation exposure to patients, shorter waiting times, and other potential advantages, but as yet the price of obtaining these benefits remains substantial.

  12. Advancements in electron cyclotron emission imaging demonstrated by the TEXTOR ECEI diagnostic upgrade

    SciTech Connect

    Tobias, B.; Kong, X.; Liang, T.; Spear, A.; Domier, C. W.; Luhmann, N. C. Jr.; Classen, I. G. J.; Boom, J. E.; Pol, M. J. van de; Jaspers, R.; Donne, A. J. H.; Park, H. K.; Munsat, T.

    2009-09-15

    A new TEXTOR electron cyclotron emission imaging system has been developed and employed, providing a diagnostic with new features and enhanced capabilities when compared to the legacy system it replaces. Optical coupling to the plasma has been completely redesigned, making use of new minilens arrays for reduced optical aberration and providing the new feature of vertical zoom, whereby the vertical coverage is now remotely adjustable on a shot-by-shot basis from 20-35 cm. Other innovations, such as the implementation of stacked quasioptical planar notch filters, allow for the diagnostic to be operated without interruption or degradation in performance during electron cyclotron resonance heating. Successful commissioning of the new diagnostic and a demonstration of the improved capabilities are presented in this paper, along with a discussion of the new technologies employed.

  13. Diagnostic performance of image navigated coronary CMR angiography in patients with coronary artery disease.

    PubMed

    Henningsson, Markus; Shome, Joy; Bratis, Konstantinos; Vieira, Miguel Silva; Nagel, Eike; Botnar, Rene M

    2017-09-11

    The use of coronary MR angiography (CMRA) in patients with coronary artery disease (CAD) remains limited due to the long scan times, unpredictable and often non-diagnostic image quality secondary to respiratory motion artifacts. The purpose of this study was to evaluate CMRA with image-based respiratory navigation (iNAV CMRA) and compare it to gold standard invasive x-ray coronary angiography in patients with CAD. Consecutive patients referred for CMR assessment were included to undergo iNAV CMRA on a 1.5 T scanner. Coronary vessel sharpness and a visual score were assigned to the coronary arteries. A diagnostic reading was performed on the iNAV CMRA data, where a lumen narrowing >50% was considered diseased. This was compared to invasive x-ray findings. Image-navigated CMRA was performed in 31 patients (77% male, 56 ± 14 years). The iNAV CMRA scan time was 7 min:21 s ± 0 min:28 s. Out of a possible 279 coronary segments, 26 segments were excluded from analysis due to stents or diameter less than 1.5 mm, resulting in a total of 253 coronary segments. Diagnostic image quality was obtained for 98% of proximal coronary segments, 94% of middle segments, and 91% of distal coronary segments. The sensitivity and specificity was 86% and 83% per patient, 80% and 92% per vessel and 73% and 95% per segment. In this study, iNAV CMRA offered a very good diagnostic performance when compared against invasive x-ray angiography. Due to the short and predictable scan time it can add clinical value as a part of a comprehensive CAD assessment protocol.

  14. Magnetic Levitation Coupled with Portable Imaging and Analysis for Disease Diagnostics.

    PubMed

    Knowlton, Stephanie M; Yenilmez, Bekir; Amin, Reza; Tasoglu, Savas

    2017-02-19

    Currently, many clinical diagnostic procedures are complex, costly, inefficient, and inaccessible to a large population in the world. The requirements for specialized equipment and trained personnel require that many diagnostic tests be performed at remote, centralized clinical laboratories. Magnetic levitation is a simple yet powerful technique and can be applied to levitate cells, which are suspended in a paramagnetic solution and placed in a magnetic field, at a position determined by equilibrium between a magnetic force and a buoyancy force. Here, we present a versatile platform technology designed for point-of-care diagnostics which uses magnetic levitation coupled to microscopic imaging and automated analysis to determine the density distribution of a patient's cells as a useful diagnostic indicator. We present two platforms operating on this principle: (i) a smartphone-compatible version of the technology, where the built-in smartphone camera is used to image cells in the magnetic field and a smartphone application processes the images and to measures the density distribution of the cells and (ii) a self-contained version where a camera board is used to capture images and an embedded processing unit with attached thin-film-transistor (TFT) screen measures and displays the results. Demonstrated applications include: (i) measuring the altered distribution of a cell population with a disease phenotype compared to a healthy phenotype, which is applied to sickle cell disease diagnosis, and (ii) separation of different cell types based on their characteristic densities, which is applied to separate white blood cells from red blood cells for white blood cell cytometry. These applications, as well as future extensions of the essential density-based measurements enabled by this portable, user-friendly platform technology, will significantly enhance disease diagnostic capabilities at the point of care.

  15. Image analysis in comparative genomic hybridization

    SciTech Connect

    Lundsteen, C.; Maahr, J.; Christensen, B.

    1995-01-01

    Comparative genomic hybridization (CGH) is a new technique by which genomic imbalances can be detected by combining in situ suppression hybridization of whole genomic DNA and image analysis. We have developed software for rapid, quantitative CGH image analysis by a modification and extension of the standard software used for routine karyotyping of G-banded metaphase spreads in the Magiscan chromosome analysis system. The DAPI-counterstained metaphase spread is karyotyped interactively. Corrections for image shifts between the DAPI, FITC, and TRITC images are done manually by moving the three images relative to each other. The fluorescence background is subtracted. A mean filter is applied to smooth the FITC and TRITC images before the fluorescence ratio between the individual FITC and TRITC-stained chromosomes is computed pixel by pixel inside the area of the chromosomes determined by the DAPI boundaries. Fluorescence intensity ratio profiles are generated, and peaks and valleys indicating possible gains and losses of test DNA are marked if they exceed ratios below 0.75 and above 1.25. By combining the analysis of several metaphase spreads, consistent findings of gains and losses in all or almost all spreads indicate chromosomal imbalance. Chromosomal imbalances are detected either by visual inspection of fluorescence ratio (FR) profiles or by a statistical approach that compares FR measurements of the individual case with measurements of normal chromosomes. The complete analysis of one metaphase can be carried out in approximately 10 minutes. 8 refs., 7 figs., 1 tab.

  16. Investigation of diagnostic and image quality attributes: comparison of screen-film to CR mammography

    NASA Astrophysics Data System (ADS)

    Fletcher-Heath, Lynn; Richards, Anne; Ryan-Kron, Susan

    2006-03-01

    Digital mammography is advancing into an arena where analog has long been the gold standard. Direct digital systems may not be the favored solution for a particular site while computed radiography (CR) mammography, remains unproven worldwide. This pilot study responds to the growing desire to acquire and display digital mammographic images by exploring the acceptability of CR mammography. Images representing a range of breast tissue types were collected from 49 subjects (17 screening; 32 diagnostic) at four clinical sites. Comparison views were collected on the same breast, under the same compression, using automatic exposure control on state-of-the-art film systems followed by CR. CR images were processed and printed to a mammography printer for hard copy feature comparison. Each image pair in the study was evaluated according to 13 image quality attributes covering noise, contrast, sharpness, and image quality in the overall captured images as well as in each of several particular breast regions (periphery and skin-line, parenchyma and fatty tissue). A rating scale from 1 to 5 was used (strong preference for film=1, strong preference for CR=5). Twelve experienced mammographers at four clinical sites scored a subset of the 49 cases for a total of 64 image pair readings. There were 64 ratings for each of 13 image quality attributes for all cases and, an additional series of scores (four or five attribute ratings) for each abnormality in the category of mass, architectural distortion and microcalcification, for a total of 1069 scores. Based on the pilot study results, it was suggested that CR was equivalent or preferred to conventional screen-film for overall image quality (38% scored 3; 46% scored >3), image contrast (27% scored 3; 59% scored >3) and sharpness (28% scored 3; 50% scored >3). No preference was found when assessing noise. This pilot study also suggested that diagnostic quality was maintained in assessing abnormalities for attributes necessary to

  17. Targeted diagnostic magnetic nanoparticles for medical imaging of pancreatic cancer.

    PubMed

    Rosenberger, I; Strauss, A; Dobiasch, S; Weis, C; Szanyi, S; Gil-Iceta, L; Alonso, E; González Esparza, M; Gómez-Vallejo, V; Szczupak, B; Plaza-García, S; Mirzaei, S; Israel, L L; Bianchessi, S; Scanziani, E; Lellouche, J-P; Knoll, P; Werner, J; Felix, K; Grenacher, L; Reese, T; Kreuter, J; Jiménez-González, M

    2015-09-28

    Highly aggressive cancer types such as pancreatic cancer possess a mortality rate of up to 80% within the first 6months after diagnosis. To reduce this high mortality rate, more sensitive diagnostic tools allowing an early stage medical imaging of even very small tumours are needed. For this purpose, magnetic, biodegradable nanoparticles prepared using recombinant human serum albumin (rHSA) and incorporated iron oxide (maghemite, γ-Fe2O3) nanoparticles were developed. Galectin-1 has been chosen as target receptor as this protein is upregulated in pancreatic cancer and its precursor lesions but not in healthy pancreatic tissue nor in pancreatitis. Tissue plasminogen activator derived peptides (t-PA-ligands), that have a high affinity to galectin-1 have been chosen as target moieties and were covalently attached onto the nanoparticle surface. Improved targeting and imaging properties were shown in mice using single photon emission computed tomography-computer tomography (SPECT-CT), a handheld gamma camera, and magnetic resonance imaging (MRI). Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Infrared imaging diagnostics for intense pulsed electron beam

    SciTech Connect

    Yu, Xiao; Shen, Jie; Liu, Wenbin; Zhong, Haowen; Zhang, Jie; Zhang, Gaolong; Le, Xiaoyun; Qu, Miao; Yan, Sha

    2015-08-15

    Infrared imaging diagnostic method for two-dimensional calorimetric diagnostics has been developed for intense pulsed electron beam (IPEB). By using a 100-μm-thick tungsten film as the infrared heat sink for IPEB, the emitting uniformity of the electron source can be analyzed to evaluate the efficiency and stability of the diode system. Two-dimensional axisymmetric finite element method heat transfer simulation, combined with Monte Carlo calculation, was performed for error estimation and optimization of the method. The test of the method was finished with IPEB generated by explosive emission electron diode with pulse duration (FWHM) of 80 ns, electron energy up to 450 keV, and a total beam current of over 1 kA. The results showed that it is possible to measure the cross-sectional energy density distribution of IPEB with energy sensitivity of 0.1 J/cm{sup 2} and spatial resolution of 1 mm. The technical details, such as irradiation protection of bremsstrahlung γ photons and the functional extensibility of the method were discussed in this work.

  19. [Update - health risks induced by ionizing radiation from diagnostic imaging].

    PubMed

    Knüsli, Claudio; Walter, Martin

    2013-12-01

    Ionizing radiation is the most thoroughly investigated exogenous noxa. Since the early 20th century it is well known that using ionizing radiation in diagnostic procedures causes cancer - physicians themselves frequently being struck by this disease in those early days of radiology. Radiation protection therefore plays an important role. Below doses of 100 Millisievert (mSv) however much research has to be accomplished yet because not only malignant tumors, but cardiovascular diseases, malformations and genetic sequelae attributable to low dose radiation have been described. Unborns, children and adolescents are highly vulnerable. Dose response correlations are subject to continuing discussions because data stem mostly from calculations studying Japanese atomic bomb survivors. Radiation exposure is not exactly known, and it is unknown, if observations of radiation induced diseases in this ethnicity can be generalized. Nowadays the main source of low dose ionizing radiation from medical diagnostics is due to computertomography (CT). Large recent clinical studies from the UK and Australia investigating cancer incidence after exposition to CT in childhood and adolescence confirm that low doses in the range of 5 mSv already significantly increase the risk of malignant diseases during follow up. Imaging techniques as ultrasound and magnetic resonance tomography therefore should be preferred whenever appropriate.

  20. The prototype imaging motional Stark effect diagnostic for ASDEX upgrade.

    PubMed

    Ford, O P; Howard, J; Wolf, R C

    2015-09-01

    This paper presents the development and testing of the prototype Imaging Motional Stark-Effect (IMSE) diagnostic, designed for ASDEX upgrade. A detailed description of the core hardware, theory of operation, and application to complex MSE spectra are presented and analytical evaluation methods suitable for the required accuracy are developed. The diagnostic is tested with a MSE-like polarised spectrum to assess the accuracy of different modulation modes suggested in previous works. Each is found to have small systematic errors due to non-ideal effects of the components, which must be carefully examined. In particular, the effect of intrinsic contrast that results from imperfect parallelism of the birefringent plates is found to have a strong effect. Methods to mitigate and correct for this are discussed. With the necessary corrections and calibrations, the accuracy of polarisation orientation is shown to be within ±0.2°. The effect of finite ellipticity is examined and the possibility to measure this to an accuracy of ±2.0° is demonstrated. The system is shown to be insensitive to broadband polarised background light, temperature variations, and critically to variations in the details of the MSE spectrum.

  1. Infrared imaging diagnostics for intense pulsed electron beam.

    PubMed

    Yu, Xiao; Shen, Jie; Qu, Miao; Liu, Wenbin; Zhong, Haowen; Zhang, Jie; Yan, Sha; Zhang, Gaolong; Le, Xiaoyun

    2015-08-01

    Infrared imaging diagnostic method for two-dimensional calorimetric diagnostics has been developed for intense pulsed electron beam (IPEB). By using a 100-μm-thick tungsten film as the infrared heat sink for IPEB, the emitting uniformity of the electron source can be analyzed to evaluate the efficiency and stability of the diode system. Two-dimensional axisymmetric finite element method heat transfer simulation, combined with Monte Carlo calculation, was performed for error estimation and optimization of the method. The test of the method was finished with IPEB generated by explosive emission electron diode with pulse duration (FWHM) of 80 ns, electron energy up to 450 keV, and a total beam current of over 1 kA. The results showed that it is possible to measure the cross-sectional energy density distribution of IPEB with energy sensitivity of 0.1 J/cm(2) and spatial resolution of 1 mm. The technical details, such as irradiation protection of bremsstrahlung γ photons and the functional extensibility of the method were discussed in this work.

  2. Target material collection for High-Energy Imaging Diagnostic

    NASA Astrophysics Data System (ADS)

    Ahmed, Maryum F.; Mcnaney, James M.; Vignes, Ryan M.; Smith, Cal A.; Masters, Nathan; Bailey, Chris; Petre, Robert B.

    2014-09-01

    The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory uses the world's largest and most energetic laser system to explore Inertial Confinement Fusion (ICF) and High-Energy-Density (HED) physics, with the potential of creating pressure and density conditions normally found in the cores of stars or large planets. During NIF experiments, the laser energy is directed to the target, driving the desired physics conditions, and the breakup of the target. During this breakup there is the potential to generate debris fields with both vaporized and solid target material, traveling at extremely high velocities (~10 km/s). For future shots, it is desirable to minimize distribution of the certain target materials within NIF. The High Energy Imaging Diagnostic (HEIDI), which comes within 8 cm of the target, will be modified to minimize the distribution of the ejected material. An external cone will be added to HEIDI which will block a larger angle than the existing hardware. Internal shielding will be added to isolate target material within the front portion of the diagnostic. A thin aluminum bumper will slow low-density vaporized material and contribute to the breakup of high velocity particles, while a thicker wall will block solid chunks. After the shot, an external cover will be installed, to contain any stray material that might be disturbed by regular operations. The target material will be retrieved from the various shielding mechanisms and assayed.

  3. Geometry-driven diffusion: an alternative approach to image filtering/segmentation in diagnostic imaging

    NASA Astrophysics Data System (ADS)

    Bajla, Ivan

    1998-02-01

    The major goal of this survey is to provide the reader with the motivation of image filtering and segmentation in diagnostic imaging, with the brief overview of the state-of- the-art of nonlinear filters based on the geometry-driven diffusion (GDD), and with a possible generalization of the GDD-filtering towards the complex problem of image segmentation, stated as minimization of particular energy functionals. An example of the application of the GDD- filtering to the task of 3D visualization of MRI data of the brain is illustrated and discussed in the paper.

  4. Surgery and diagnostic imaging in abdominal Crohn's disease.

    PubMed

    Botti, Fiorenzo; Caprioli, Flavio; Pettinari, Diego; Carrara, Alberto; Magarotto, Andrea; Contessini Avesani, Ettore

    2015-03-01

    Surgery is well-established option for the treatment of Crohn's disease that is refractory to medical therapy and for complications of the disease, including strictures, fistulas, abscesses, bleeding that cannot be controlled endoscopically, and neoplastic degeneration. For a condition like Crohn's disease, where medical management is the rule, other indications for surgery are considered controversial, because the therapeutic effects of surgery are limited to the resolution of complications and the rate of recurrence is high, especially at sites of the surgical anastomosis. In the authors' opinion, however, surgery should not be considered a last-resort treatment: in a variety of situations, it should be regarded as an appropriate solution for managing this disease. Based on a review of the literature and their own experience, the authors examine some of the possibilities for surgical interventions in Crohn's disease and the roles played in these cases by diagnostic imaging modalities.

  5. Diagnostic accuracy of an ultrasonic multiple transducer cardiac imaging system

    NASA Technical Reports Server (NTRS)

    Popp, R. L.; Brown, O. R.; Harrison, D. C.

    1975-01-01

    An ultrasonic multiple-transducer imaging system for intracardiac structure visualization is developed in order to simplify visualization of the human heart in vivo without radiation hazard or invasion of the body. Results of the evaluation of the diagnostic accuracy of the devised system in a clinical setting for adult patients are presented and discussed. Criteria are presented for recognition of mitral valva prolapse, mitral stenosis, pericardial effusion, atrial septal defect, and left ventricular dyssynergy. The probable cause for false-positive and false-negative diagnoses is discussed. However, hypertrophic myopathy and congestive myopathy were unable to be detected. Since only qualitative criteria were used, it was not possible to differentiate patients with left ventricular volume overload from patients without cardiac pathology.

  6. Diagnostic accuracy of an ultrasonic multiple transducer cardiac imaging system

    NASA Technical Reports Server (NTRS)

    Popp, R. L.; Brown, O. R.; Harrison, D. C.

    1975-01-01

    An ultrasonic multiple-transducer imaging system for intracardiac structure visualization is developed in order to simplify visualization of the human heart in vivo without radiation hazard or invasion of the body. Results of the evaluation of the diagnostic accuracy of the devised system in a clinical setting for adult patients are presented and discussed. Criteria are presented for recognition of mitral valva prolapse, mitral stenosis, pericardial effusion, atrial septal defect, and left ventricular dyssynergy. The probable cause for false-positive and false-negative diagnoses is discussed. However, hypertrophic myopathy and congestive myopathy were unable to be detected. Since only qualitative criteria were used, it was not possible to differentiate patients with left ventricular volume overload from patients without cardiac pathology.

  7. Targeting SR-BI for Cancer Diagnostics, Imaging and Therapy

    PubMed Central

    Rajora, Maneesha A.; Zheng, Gang

    2016-01-01

    Scavenger receptor class B type I (SR-BI) plays an important role in trafficking cholesteryl esters between the core of high density lipoprotein and the liver. Interestingly, this integral membrane protein receptor is also implicated in the metabolism of cholesterol by cancer cells, whereby overexpression of SR-BI has been observed in a number of tumors and cancer cell lines, including breast and prostate cancers. Consequently, SR-BI has recently gained attention as a cancer biomarker and exciting target for the direct cytosolic delivery of therapeutic agents. This brief review highlights these key developments in SR-BI-targeted cancer therapies and imaging probes. Special attention is given to the exploration of high density lipoprotein nanomimetic platforms that take advantage of upregulated SR-BI expression to facilitate targeted drug-delivery and cancer diagnostics, and promising future directions in the development of these agents. PMID:27729859

  8. Cost Of Managing Digital Diagnostic Images For A 614 Bed Hospital

    NASA Astrophysics Data System (ADS)

    Dwyer, Samuel J.; Templeton, Arch W.; Martin, Norman L.; Cook, Larry T.; Lee, Kyo R.; Levine, Errol; Batnitzky, Solomon; Preston, David F.; Rosenthal, Stanton J.; Price, Hilton I.; Anderson, William H.; Tarlton, Mark A.; Faszold, Susan

    1982-01-01

    The cost of recording and archiving digital diagnostic imaging data is presented for a Radiology Department serving a 614 bed University Hospital with a large outpatient population. Digital diagnostic imaging modalities include computed tomography, nuclear medicine, ultrasound, and digital radiography. The archiving media include multiformat video film recordings, magnetic tapes, and disc storage. The estimated cost per patient for the archiving of digital diagnostic imaging data is presented.

  9. Acquiring diagnostic DaTSCAN images in claustrophobic or difficult patients using a 180 degrees configuration.

    PubMed

    Notghi, Alp; O'Brien, Joseph; Clarke, Elizabeth A; Thomson, William H

    2010-03-01

    In this study, we have investigated the feasibility of a 180 degrees DaTSCAN brain SPECT acquisition. This technique has the advantage of being 'open view' for the patient and therefore more acceptable for claustrophobic patients. It also enables easier access for a technologist to hold the patient's head during acquisition to reduce movement in confused patients or in those with severe tremor. In the first part of this study, we validated the practicality and image quality of a 180 degrees acquisition using a DaTSCAN Alderson head phantom with different camera configurations on GE Infinia and Philips AXIS gamma cameras. The effect on image quality of using half the acquisition time was also assessed. In the second part of the study, 50 sets of patient data were reprocessed by reconstructing half of the 360 degrees data to mimic a single-head 180 degrees acquisition. The 180 degrees images were then compared with 360 degrees images for the same patient using a visual score system. The effect of half-time 180 degrees data acquisition on quantification was also assessed using GE QuantiSPECT software. All phantom images from 180 degrees acquisitions contained some degree of distortion at the periphery, but clearly retain the presence of centrally positioned caudate and putamen; hence 180 degrees acquisitions were deemed to produce clinically useful diagnostic images. The shorter (half) acquisition time leads to noisier but acceptable images for all configurations. In the patient study, there was complete agreement between the two reporters with no clinical difference in the diagnostic accuracy between the 180 degrees and 360 degrees images. However, 6 of 50 180 degrees images were marked as poor quality but reportable, compared with 0 of 50 in 360 degrees images. Quantification gave consistently lower nuclei to background ratio values for 180 degrees compared with 360 degrees for normal and abnormal patients. It is possible to obtain diagnostic DaTSCAN images using

  10. Diagnostic imaging of benign and malignant neck masses in children—a pictorial review

    PubMed Central

    Harave, Srikrishna

    2016-01-01

    Neck masses are frequently encountered in pediatric medicine, and can present a diagnostic dilemma for the clinicians involved. There are several means by which neck masses in children can be subdivided, for example by age at presentation, anatomical location including compartments and fascia of the neck, their classical appearance when imaged, or by etiology. When imaging children the clinicians must be mindful of radiation exposure and as such ultrasound (US) is often attempted first. Cross sectional imaging can be helpful for problem solving with CT being particularly useful for assessing the patient in more acute scenarios, for example when there is airway compromise. Nuclear medicine scintigraphy has a role in specific circumstances and can aid in staging in the presence of malignancy. If required, additional acquisition by means of magnetic resonance imaging (MRI) and computed tomography (CT) can be considered. This pictorial review describe the diagnostic imaging of (I) congenital and Developmental Pathologies, including thyroglossal duct cyst, branchial cleft cyst, cystic hygroma, dermoid cyst, thymic cyst and ectopic thymus; (II) neoplastic lesions, including hemangiomas and vascular malformations, pilomatrixoma, neurofibroma, neuroblastoma, rhabdomyosarcoma, papillary thyroid cancer, lymphoma & leukemia; (III) neck masses of Infective causes, including lymphadenitis, retropharyngeal and peritonsilar abscess, salivary gland inflammation; and (IV) other miscellaneous lesions, including ranula, sternocleidomastoid fibromatosis coli, and goiter. Neck masses are common in the pediatric population with a broad and varied differential; malignant etiologies are less frequently encountered when compared with adults but an awareness of its potential is important when reviewing imaging. PMID:27942480

  11. Diagnostic performance on briefly presented digital pathology images

    PubMed Central

    Houghton, Joseph P; Smoller, Bruce R; Leonard, Niamh; Stevenson, Michael R; Dornan, Tim

    2015-01-01

    Background: Identifying new and more robust assessments of proficiency/expertise (finding new “biomarkers of expertise”) in histopathology is desirable for many reasons. Advances in digital pathology permit new and innovative tests such as flash viewing tests and eye tracking and slide navigation analyses that would not be possible with a traditional microscope. The main purpose of this study was to examine the usefulness of time-restricted testing of expertise in histopathology using digital images. Methods: 19 novices (undergraduate medical students), 18 intermediates (trainees), and 19 experts (consultants) were invited to give their opinion on 20 general histopathology cases after 1 s and 10 s viewing times. Differences in performance between groups were measured and the internal reliability of the test was calculated. Results: There were highly significant differences in performance between the groups using the Fisher's least significant difference method for multiple comparisons. Differences between groups were consistently greater in the 10-s than the 1-s test. The Kuder–Richardson 20 internal reliability coefficients were very high for both tests: 0.905 for the 1-s test and 0.926 for the 10-s test. Consultants had levels of diagnostic accuracy of 72% at 1 s and 83% at 10 s. Conclusions: Time-restricted tests using digital images have the potential to be extremely reliable tests of diagnostic proficiency in histopathology. A 10-s viewing test may be more reliable than a 1-s test. Over-reliance on “at a glance” diagnoses in histopathology is a potential source of medical error due to over-confidence bias and premature closure. PMID:26605121

  12. Diagnostic imaging of canine elbow dysplasia: a review.

    PubMed

    Cook, Cristi R; Cook, James L

    2009-02-01

    Canine elbow dysplasia (CED) is a common developmental disorder of the cubital joint of dogs. CED is comprised of fragmented medial coronoid process (FMCP), ununited anconeal process (UAP), osteochondrosis (OC), and elbow incongruity. Multiple imaging modalities have been used to assess this complex of disorders and the severity of the pathologic changes. Radiography has been used as a surveying tool for assessment of CED for many years. Recently, alternate techniques and modalities have expanded our knowledge of CED and our clinical approach to this disorder. Nuclear medicine has been used to aid in localizing lameness to the elbow joint. Ultrasonography has proven helpful for imaging the soft tissue structures adjacent to the joint as well as superficial bone abnormalities, including visualization of FMCP. Computed tomography and magnetic resonance imaging are advanced imaging modalities that allow visualization of the elbow in multiple planes and into three-dimensional reconstructions, thus allowing lesions to be more accurately and comprehensively visualized. Assessment of elbow incongruity in particular has been benefitted by these advanced imaging techniques because of the importance of sagittal and dorsal plane imaging and reconstructions for accurately determining the relationships between radial and ulnar articular surfaces. Comparative studies using multiple techniques and imaging modalities with correlation to reference standards and patient outcomes will be vital to continued progress in this area.

  13. Histological Image Feature Mining Reveals Emergent Diagnostic Properties for Renal Cancer.

    PubMed

    Kothari, Sonal; Phan, John H; Young, Andrew N; Wang, May D

    2011-11-01

    Computer-aided histological image classification systems are important for making objective and timely cancer diagnostic decisions. These systems use combinations of image features that quantify a variety of image properties. Because researchers tend to validate their diagnostic systems on specific cancer endpoints, it is difficult to predict which image features will perform well given a new cancer endpoint. In this paper, we define a comprehensive set of common image features (consisting of 12 distinct feature subsets) that quantify a variety of image properties. We use a data-mining approach to determine which feature subsets and image properties emerge as part of an "optimal" diagnostic model when applied to specific cancer endpoints. Our goal is to assess the performance of such comprehensive image feature sets for application to a wide variety of diagnostic problems. We perform this study on 12 endpoints including 6 renal tumor subtype endpoints and 6 renal cancer grade endpoints. Keywords-histology, image mining, computer-aided diagnosis.

  14. Diagnostic Confidence of Run-Off CT-Angiography as the Primary Diagnostic Imaging Modality in Patients Presenting with Acute or Chronic Peripheral Arterial Disease

    PubMed Central

    Werncke, Thomas; Ringe, Kristina Imeen; von Falck, Christian; Kruschewski, Martin; Wacker, Frank; Meyer, Bernhard Christian

    2015-01-01

    Objectives To investigate the reliability of CT-angiography of the lower extremities (run-off CTA) to derive a treatment decision in patients with acute and chronic peripheral artery disease (PAD). Materials and Methods 314 patients referred for run-off CTA were includ-ed in this retrospective study. First, diagnostic confidence of run-off CTA to derive a treat-ment decision was assessed in an interdisciplinary vascular conference using a 2 point scale (sufficient or not sufficient diagnostic confidence) and compared with the image quality eval-uated by two readers in consensus in four different levels (abdominopelvic, thigh, calf, foot arteries). Second, reliability of treatment decision was verified in all patients undergoing re-vascularization therapy. Results Diagnostic confidence of run-off CTA to derive a treatment deci-sion was sufficient in all patients with acute and in 97% of patients (215/221) with chronic PAD, whereas the rate of run-off CTA with non-diagnostic image quality was considerably higher in the calf and foot level (acute vs. chronic; calf: 28% vs.17%; foot: 52% vs. 20%). Reliability of treatment decision was superior for patients with chronic (123/133 = 92%) than for patients with acute PAD (64/78 = 82%, P = 0.02). Conclusion Run-off CTA is a reliable imaging modality for primary diag-nostic work-up of patients with acute and chronic PAD. PMID:25835948

  15. Diagnostic confidence of run-off CT-angiography as the primary diagnostic imaging modality in patients presenting with acute or chronic peripheral arterial disease.

    PubMed

    Werncke, Thomas; Ringe, Kristina Imeen; von Falck, Christian; Kruschewski, Martin; Wacker, Frank; Meyer, Bernhard Christian

    2015-01-01

    To investigate the reliability of CT-angiography of the lower extremities (run-off CTA) to derive a treatment decision in patients with acute and chronic peripheral artery disease (PAD). 314 patients referred for run-off CTA were includ-ed in this retrospective study. First, diagnostic confidence of run-off CTA to derive a treat-ment decision was assessed in an interdisciplinary vascular conference using a 2 point scale (sufficient or not sufficient diagnostic confidence) and compared with the image quality eval-uated by two readers in consensus in four different levels (abdominopelvic, thigh, calf, foot arteries). Second, reliability of treatment decision was verified in all patients undergoing re-vascularization therapy. Diagnostic confidence of run-off CTA to derive a treatment deci-sion was sufficient in all patients with acute and in 97% of patients (215/221) with chronic PAD, whereas the rate of run-off CTA with non-diagnostic image quality was considerably higher in the calf and foot level (acute vs. chronic; calf: 28% vs.17%; foot: 52% vs. 20%). Reliability of treatment decision was superior for patients with chronic (123/133 = 92%) than for patients with acute PAD (64/78 = 82%, P = 0.02). Run-off CTA is a reliable imaging modality for primary diag-nostic work-up of patients with acute and chronic PAD.

  16. High-Accuracy Ultrasound Contrast Agent Detection Method for Diagnostic Ultrasound Imaging Systems.

    PubMed

    Ito, Koichi; Noro, Kazumasa; Yanagisawa, Yukari; Sakamoto, Maya; Mori, Shiro; Shiga, Kiyoto; Kodama, Tetsuya; Aoki, Takafumi

    2015-12-01

    An accurate method for detecting contrast agents using diagnostic ultrasound imaging systems is proposed. Contrast agents, such as microbubbles, passing through a blood vessel during ultrasound imaging are detected as blinking signals in the temporal axis, because their intensity value is constantly in motion. Ultrasound contrast agents are detected by evaluating the intensity variation of a pixel in the temporal axis. Conventional methods are based on simple subtraction of ultrasound images to detect ultrasound contrast agents. Even if the subject moves only slightly, a conventional detection method will introduce significant error. In contrast, the proposed technique employs spatiotemporal analysis of the pixel intensity variation over several frames. Experiments visualizing blood vessels in the mouse tail illustrated that the proposed method performs efficiently compared with conventional approaches. We also report that the new technique is useful for observing temporal changes in microvessel density in subiliac lymph nodes containing tumors. The results are compared with those of contrast-enhanced computed tomography.

  17. Diagnostic accuracy and image quality using a digital camera for teledermatology.

    PubMed

    Krupinski, E A; LeSueur, B; Ellsworth, L; Levine, N; Hansen, R; Silvis, N; Sarantopoulos, P; Hite, P; Wurzel, J; Weinstein, R S; Lopez, A M

    1999-01-01

    The study was designed to evaluate the effectiveness of digital photography for dermatologic diagnoses and compare it with in-person diagnoses. Patients referred for specialty consultations (n = 308) were recruited from a university dermatology clinic. Patients were examined in-person by one of three board-certified dermatologists who provided clinical diagnoses. Digital photos were obtained on all patients and were evaluated as computer images by a panel of dermatologists. There was 83% concordance between in-person versus digital photo diagnoses. Intradermatologist concordance averaged 84%, and interdermatologist concordance averaged 81%. Decision confidence was rated as "very definite" to "definite" 62% of the time. Concordance with biopsy results was achieved in 76% of the cases. Image sharpness and color quality were rated "good" to "excellent" 83% and 93% of the time, respectively. Digital photography for store-and-forward teledermatology produces high-quality images and diagnostic concordance rates that compare favorably with in-person clinical diagnoses.

  18. Prediction of liver cirrhosis, using diagnostic imaging tools

    PubMed Central

    Yeom, Suk Keu; Lee, Chang Hee; Cha, Sang Hoon; Park, Cheol Min

    2015-01-01

    Early diagnosis of liver cirrhosis is important. Ultrasound-guided liver biopsy is the gold standard for diagnosis of liver cirrhosis. However, its invasiveness and sampling bias limit the applicability of the method. Basic imaging for the diagnosis of liver cirrhosis has developed over the last few decades, enabling early detection of morphological changes of the liver by ultrasonography (US), computed tomography, and magnetic resonance imaging (MRI). They are also accurate diagnostic methods for advanced liver cirrhosis, for which early diagnosis is difficult. There are a number of ways to compensate for this difficulty, including texture analysis to more closely identify the homogeneity of hepatic parenchyma, elastography to measure the stiffness and elasticity of the liver, and perfusion studies to determine the blood flow volume, transit time, and velocity. Amongst these methods, elastography using US and MRI was found to be slightly easier, faster, and able to provide an accurate diagnosis. Early diagnosis of liver cirrhosis using MRI or US elastography is therefore a realistic alternative, but further research is still needed. PMID:26301049

  19. Acoustic imaging for diagnostics of chemically reacting systems

    NASA Technical Reports Server (NTRS)

    Ramohalli, K.; Seshan, P.

    1983-01-01

    The concept of local diagnostics, in chemically reacting systems, with acoustic imaging is developed. The elements of acoustic imaging through ellipsoidal mirrors are theoretically discussed. In a general plan of the experimental program, the first system is chosen in these studies to be a simple open jet, non premixed turbulent flame. Methane is the fuel and enriched air is the oxidizer. This simple chemically reacting flow system is established at a Reynolds number (based on cold viscosity) of 50,000. A 1.5 m diameter high resolution acoustic mirror with an f-number of 0.75 is used to map the acoustic source zone along the axis of the flame. The results are presented as acoustic power spectra at various distances from the nozzle exit. It is seen that most of the reaction intensity is localized in a zone within 8 diameters from the exit. The bulk reactions (possibly around the periphery of the larger eddies) are evenly distributed along the length of the flame. Possibilities are seen for locally diagnosing single zones in a multiple cluster of reaction zones that occur frequently in practice. A brief outline is given of the future of this work which will be to apply this technique to chemically reacting flows not limited to combustion.

  20. Millimeter-Wave Imaging Technology Advancements for Plasma Diagnostics Applications

    NASA Astrophysics Data System (ADS)

    Kong, Xiangyu

    To realize fusion plant, the very first step is to understand the fundamental physics of materials under fusion conditions, i.e. to understand fusion plasmas. Our research group, Plasma Diagnostics Group, focuses on developing advanced tools for physicists to extract as much information as possible from fusion plasmas at millions degrees. The Electron Cyclotron Emission Imaging (ECEI) diagnostics is a very useful tool invented in this group to study fusion plasma electron temperature and it fluctuations. This dissertation presents millimeter wave imaging technology advances recently developed in this group to improve the ECEI system. New technologies made it more powerful to image and visualize magneto-hydrodynamics (MHD) activities and micro-turbulence in fusion plasmas. Topics of particular emphasis start from development of miniaturized elliptical substrate lens array. This novel substrate lens array replaces the previous generation substrate lens, hyper-hemispherical substrate lens, in terms of geometry. From the optical performance perspective, this substitution not only significantly simplifies the optical system with improved optical coupling, but also enhances the RF/LO coupling efficiency. By the benefit of the mini lens focusing properties, a wideband dual-dipole antenna array is carefully designed and developed. The new antenna array is optimized simultaneously for receiving both RF and LO, with sharp radiation patterns, low side-lobe levels, and less crosstalk between adjacent antennas. In addition, a high frequency antenna is also developed, which extends the frequency limit from 145 GHz to 220 GHz. This type of antenna will be used on high field operation tokamaks with toroidal fields in excess of 3 Tesla. Another important technology advance is so-called extended bandwidth double down-conversion electronics. This new electronics extends the instantaneous IF coverage from 2 to 9.2 GHz to 2 to 16.4 GHz. From the plasma point of view, it means that the

  1. Angiographic CT with intravenous contrast injection compared with conventional rotational angiography in the diagnostic work-up of cerebral aneurysms.

    PubMed

    Gölitz, P; Struffert, T; Knossalla, F; Saake, M; Ott, S; Ganslandt, O; Doerfler, A

    2012-05-01

    Noninvasive imaging of cerebral aneurysms is still considered inferior to conventional angiography. The purpose of this study was to evaluate the diagnostic accuracy of ivACT in the assessment of intracranial aneurysms compared with 3D-DSA. We included 13 patients with 15 incidental unruptured saccular aneurysms scheduled for diagnostic angiographic work-up in our study. In each patient, we performed an ivACT and a conventional angiography including a 3D rotational run. During postprocessing, MPR images were generated for each technique. Maximal aneurysm diameter, neck diameter, aneurysm height, maximum width, bulge height, parent artery diameter, and angle between the parent artery and aneurysm apex were measured for each aneurysm. 3D-DSA and ivACT both provided images of high quality without artificial disturbances (ie, motion artifacts). Measurements of all parameters resulted in comparable values for both modalities with a strong correlation (P ≤ .001). ivACT is feasible for the noninvasive visualization of saccular cerebral aneurysms and may provide reliable diagnostic information for the assessment of aneurysm size and geometry comparable with conventional intra-arterial 3D rotational angiography. These preliminary results might be a first promising step to replacing conventional angiography in preinterventional aneurysm imaging.

  2. Scatterometry or imaging overlay: a comparative study

    NASA Astrophysics Data System (ADS)

    Hsu, Simon C. C.; Pai, Yuan Chi; Chen, Charlie; Yu, Chun Chi; Hsing, Henry; Wu, Hsing-Chien; Kuo, Kelly T. L.; Amir, Nuriel

    2015-03-01

    Most fabrication facilities today use imaging overlay measurement methods, as it has been the industry's reliable workhorse for decades. In the last few years, third-generation Scatterometry Overlay (SCOL™) or Diffraction Based Overlay (DBO-1) technology was developed, along another DBO technology (DBO-2). This development led to the question of where the DBO technology should be implemented for overlay measurements. Scatterometry has been adopted for high volume production in only few cases, always with imaging as a backup, but scatterometry overlay is considered by many as the technology of the future. In this paper we compare imaging overlay and DBO technologies by means of measurements and simulations. We outline issues and sensitivities for both technologies, providing guidelines for the best implementation of each. For several of the presented cases, data from two different DBO technologies are compared as well, the first with Pupil data access (DBO-1) and the other without pupil data access (DBO-2). Key indicators of overlay measurement quality include: layer coverage, accuracy, TMU, process robustness and robustness to process changes. Measurement data from real cases across the industry are compared and the conclusions are also backed by simulations. Accuracy is benchmarked with reference OVL, and self-consistency, showing good results for Imaging and DBO-1 technology. Process sensitivity and metrology robustness are mostly simulated with MTD (Metrology Target Designer) comparing the same process variations for both technologies. The experimental data presented in this study was done on ten advanced node layers and three production node layers, for all phases of the IC fabrication process (FEOL, MEOL and BEOL). The metrology tool used for most of the study is KLA-Tencor's Archer 500LCM system (scatterometry-based and imaging-based measurement technologies on the same tool) another type of tool is used for DBO-2 measurements. Finally, we conclude that

  3. [Adrenal tumors: principles of imaging and differential diagnostics].

    PubMed

    Degenhart, C

    2014-10-01

    Adrenal masses are very common and are usually detected incidentally. Less frequently, imaging is performed for the localization of the underlying lesion in the case of endocrine disease. The differentiation between adenomas and non-adenomas is fundamental. Adenomas show a low density on unenhanced computed tomography (CT) and a rapid washout of contrast agents. In magnetic resonance imaging (MRI) adenomas are characterized by a low signal in opposed phase imaging as compared to in phase imaging. According to the literature a density of less than 10 HU in an adrenal mass has a specificity of 98% and a sensitivity of 71% for the presence of an adenoma and MRI is slightly more sensitive. Some adrenal lesions, e.g. cysts or myelolipomas can be diagnosed with high accuracy due to pathognomonic findings. In the majority of cases the synopsis of imaging along with clinical and laboratory findings is necessary for a reliable diagnosis. For the evaluation of an adrenal mass the CT examination should begin with an unenhanced scan, if necessary followed by a washout examination. In the case of MRI in phase and opposed phase imaging are essential components of the examination.

  4. Additive diagnostic role of imaging in glaucoma: optical coherence tomography and retinal nerve fiber layer photography.

    PubMed

    Kim, Ko Eun; Kim, Seok Hwan; Oh, Sohee; Jeoung, Jin Wook; Suh, Min Hee; Seo, Je Hyun; Kim, Martha; Park, Ki Ho; Kim, Dong Myung

    2014-11-20

    To investigate the additive diagnostic role of spectral-domain optical coherence tomography (SD-OCT) and red-free retinal nerve fiber layer photography (RNFLP) in making clinical glaucoma diagnosis. Four diagnostic combination sets, including the most recent image from each measurement of 196 glaucoma eyes (including the 44 preperimetric glaucoma eyes) and 101 healthy eyes, were prepared: (1) stereo disc photography and Humphrey visual field (SH), (2) SH and SD-OCT (SHO), (3) SH and RNFLP (SHR), and (4) SHR and SD-OCT (SHRO). Each randomly sorted set was serially presented at 1-month intervals to five glaucoma specialists who were asked to evaluate them in a subjective and independent manner. The specialists' glaucoma-diagnostic performances based on the sets were then compared. For each specialist, adding SD-OCT to SH or SHR increased the glaucoma-diagnostic sensitivity but not to a level of statistical significance. For one specialist, adding RNFLP to SH significantly increased the sensitivity. Each specialist showed a high level of specificity regardless of the diagnostic set. The overall sensitivity of all specialists' assessments was significantly increased by adding RNFLP or the combination of SD-OCT and RNFLP to SH (P < 0.001); however, adding SD-OCT to SH or SHR did not significantly increase the sensitivity. A similar relationship was noted also for the preperimetric glaucoma subgroup. In contrast to RNFLP, SD-OCT did not significantly enhance the diagnostic accuracy of detecting glaucoma or even of preperimetric glaucoma. Our results suggest that, at least for glaucoma specialists, the additive diagnostic role of OCT is limited. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  5. Diagnostic imaging and interventional therapy of hepatocellular carcinoma.

    PubMed

    Palma, L D

    1998-08-01

    Diagnostic imaging has many important roles in the management of patients with hepatocellular carcinoma (HCC). In diagnosis, lipiodol CT (LCT) has been shown to be the most sensitive imaging modality (90-97%) for all sizes of lesions; all other modalities have high sensitivities for lesions 1-3 cm but low sensitivities for lesions < 1 cm (ultrasound 33-37%, conventional CT 20-42% and digital subtraction angiography 40-55%). All imaging modalities understage HCC. Once again LCT is the most accurate method of evaluating the extent of tumour, but even this method does not identify all satellite nodules. Ultrasound has been proposed as a screening method, but this cannot be justified on the basis of its results or cost benefit analysis. Both CT and dynamic MRI play useful roles in evaluating the efficacy and follow-up of patients undergoing chemoembolization (TACE) and percutaneous ethanol injection (PEI). Although surgery remains the best treatment of HCC, it is unsuitable in most of the cases which would be better treated with interventional therapy. This article presents a review of the literature regarding the use of TACE, PEI or a combination of both procedures in the treatment of HCC. A multicentric study has shown that patients with monofocal lesions less than 5 cm in diameter are better treated with PEI, which is therefore a good alternative to the surgical treatment; patients with multifocal lesions (maximum of three lesions) show a better survival with TACE. Combined treatment with TACE and PEI proves to be effective in patients with large HCC.

  6. Dermoscopy analysis of RGB-images based on comparative features

    NASA Astrophysics Data System (ADS)

    Myakinin, Oleg O.; Zakharov, Valery P.; Bratchenko, Ivan A.; Artemyev, Dmitry N.; Neretin, Evgeny Y.; Kozlov, Sergey V.

    2015-09-01

    In this paper, we propose an algorithm for color and texture analysis for dermoscopic images of human skin based on Haar wavelets, Local Binary Patterns (LBP) and Histogram Analysis. This approach is a modification of «7-point checklist» clinical method. Thus, that is an "absolute" diagnostic method because one is using only features extracted from tumor's ROI (Region of Interest), which can be selected manually and/or using a special algorithm. We propose additional features extracted from the same image for comparative analysis of tumor and healthy skin. We used Euclidean distance, Cosine similarity, and Tanimoto coefficient as comparison metrics between color and texture features extracted from tumor's and healthy skin's ROI separately. A classifier for separating melanoma images from other tumors has been built by SVM (Support Vector Machine) algorithm. Classification's errors with and without comparative features between skin and tumor have been analyzed. Significant increase of recognition quality with comparative features has been demonstrated. Moreover, we analyzed two modes (manual and automatic) for ROI selecting on tumor and healthy skin areas. We have reached 91% of sensitivity using comparative features in contrast with 77% of sensitivity using the only "absolute" method. The specificity was the invariable (94%) in both cases.

  7. Final Report - DOE Center for Laser Imaging and Cancer Diagnostics

    SciTech Connect

    Alfano, Robert R.; Koutcher, Jason A.

    2002-10-31

    This Final Report summarizes the significant progress made by the researchers, students and staff of the Center for Laser Imaging and Cancer Diagnostics (CLICD) from January 1998 through May 2002. During this period, the Center supported several projects. Most projects were proposed initially, some were added subsequently as their relevance and importance to the DOE mission became evident. DOE support has been leveraged to obtain continuing funding for some projects. Leveraged funds come from various sources, including NIH, Army, NSF and the Air Force. The goal of the Center was to develop laser-based instruments for use in the detection and diagnosis of major diseases, with an emphasis on detection and diagnosis of various cancers. Each of the supported projects is a collaborative effort between physicists and laser scientists and the City College of New York and noted physicians, surgeons, pathologists, and biologists located at medical centers in the Metropolitan area. The participating institutions were: City College of New York Institute for Ultrafast Lasers and Spectroscopy, Hackensack University Medical Center, Lawrence Livermore National Laboratory, Memorial Sloan Kettering Cancer Center, and New York Eye and Ear Institute. Each of the projects funded by the Center is grouped into one of four research categories: a) Disease Detection, b) Non-Disease Applications, c) New Diagnostic Tools, and, d) Education, Training, Outreach and Dissemination. The progress achieved by the multidisciplinary teams was reported in 51 publications and 32 presentations at major national conferences. Also, one U.S. patent was obtained and six U.S. patent applications have been filed for innovations resulting from the projects sponsored by the Center.

  8. Diagnostic impact of proton MR-spectroscopy versus image-guided stereotactic biopsy.

    PubMed

    Setzer, M; Herminghaus, S; Marquardt, G; Tews, D S; Pilatus, U; Seifert, V; Zanella, F; Lanfermann, H

    2007-01-01

    The aim of this study was to compare the diagnostic accuracy of (1)H MR-spectroscopy versus image-guided stereotactic biopsy. A cohort of 83 consecutive patients with a broad spectrum of brain lesions were examined. Prior to stereotactic biopsy, the patients were subjected to (1)H MR-spectroscopy examination. Diagnostic accuracy of (1)H MR-spectroscopy and image guided stereotactic biopsy was determined for the largest diagnostic subgroups. Each diagnostic procedure was tested for concordance in every subgroup. The subgroups of patients comprised: low grade glioma, high grade glioma (grades III and IV), lymphoma and metastasis. For the sensitivity of (1)H MR-spectroscopy ranged from 87.7 in high grade glioma to 92.3% in metastasis and for specificity from 93.3% for high grade glioma to 100% in low grade glioma. The highest positive predictive value of 100% was reached in the subgroup of low grade glioma. The highest negative predictive value was reached in lymphoma and metastasis, 100%. The kappa values were highly significant for all comparisons (p<0.001). The co-efficient ranged from 0.68 to 0.84. It was lowest in assessing high grade glioma and highest in lymphoma. Compared with each other (1)H MR-spectroscopy and image-guided stereotactic biopsy showed a moderate to good, statistically highly significant concordance. In patients in whom operation is at an increased risk e.g., due to severe medical illness, (1)H MR-spectroscopy as a noninvasive procedure may be sufficient to assess the diagnosis.

  9. Effect of slice thickness on image noise and diagnostic content of single-source-dual energy computed tomography

    NASA Astrophysics Data System (ADS)

    Alshipli, Marwan; Kabir, Norlaili A.

    2017-05-01

    Computed tomography (CT) employs X-ray radiation to create cross-sectional images. Dual-energy CT acquisition includes the images acquired from an alternating voltage of X-ray tube: a low- and a high-peak kilovoltage. The main objective of this study is to determine the best slice thickness that reduces image noise with adequate diagnostic information using dual energy CT head protocol. The study used the ImageJ software and statistical analyses to aid the medical image analysis of dual-energy CT. In this study, ImageJ software and F-test were utilised as the combination methods to analyse DICOM CT images. They were used to investigate the effect of slice thickness on noise and visibility in dual-energy CT head protocol images. Catphan-600 phantom was scanned at different slice thickness values;.6, 1, 2, 3, 4, 5 and 6 mm, then quantitative analyses were carried out. The DECT operated in helical mode with another fixed scan parameter values. Based on F-test statistical analyses, image noise at 0.6, 1, and 2 mm were significantly different compared to the other images acquired at slice thickness of 3, 4, 5, and 6 mm. However, no significant differences of image noise were observed at 3, 4, 5, and 6 mm. As a result, better diagnostic image value, image visibility, and lower image noise in dual-energy CT head protocol was observed at a slice thickness of 3 mm.

  10. Utilization and likelihood of radiologic diagnostic imaging in patients with implantable cardiac defibrillators.

    PubMed

    Nazarian, Saman; Reynolds, Matthew R; Ryan, Michael P; Wolff, Steven D; Mollenkopf, Sarah A; Turakhia, Mintu P

    2016-01-01

    To examine imaging utilization in a matched cohort of patients with and without implantable cardioverter defibrillators (ICD) and to project magnetic resonance imaging (MRI) utilization over a 10-year period. The Truven Health MarketScan Commercial claims and Medicare Supplemental health insurance claims data were used to identify patients with continuous health plan enrollment in 2009-2012. Patients with ICDs were identified using ICD-9 and CPT codes, and matched to patients with the same demographic and comorbidity profile, but no record of device implantation. Diagnostic imaging utilization was compared across the matched cohorts, in total, by imaging categories, and in subpopulations of stroke, back pain, and joint pain. MRI use in the nonimplant group over the 4-year period was extrapolated out to 10 years for ICD-indicated patients. A cohort of 18,770 matched patients were identified; average age 65.5 ± 13.38 and 21.9% female. ICD patients had significantly less MRI imaging (0.23 0.70 SD vs. 0.00 0.08 SD, P < 0.0001) than nonimplant patients. Among patients with records of stroke/transient ischemic attack (TIA) (ICD 5%, nonimplant 4%) and accompanying diagnostic imaging, 44% of nonimplant patients underwent MRI vs. 1% of ICD patients (P < 0.0001). Forecast models estimated that 53% to 64% of ICD-eligible patients may require an MRI within 10 years. MRI utilization is lower in ICD patients compared to nonimplant patients, yet the burden of incident stroke/TIA, back, and joint pain suggests an unmet need for MR-conditional devices. © 2015 The Authors Journal of Magnetic Resonance Imaging published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.

  11. Utilization and likelihood of radiologic diagnostic imaging in patients with implantable cardiac defibrillators

    PubMed Central

    Reynolds, Matthew R.; Ryan, Michael P.; Wolff, Steven D.; Mollenkopf, Sarah A.; Turakhia, Mintu P.

    2015-01-01

    Purpose To examine imaging utilization in a matched cohort of patients with and without implantable cardioverter defibrillators (ICD) and to project magnetic resonance imaging (MRI) utilization over a 10‐year period. Materials and Methods The Truven Health MarketScan Commercial claims and Medicare Supplemental health insurance claims data were used to identify patients with continuous health plan enrollment in 2009–2012. Patients with ICDs were identified using ICD‐9 and CPT codes, and matched to patients with the same demographic and comorbidity profile, but no record of device implantation. Diagnostic imaging utilization was compared across the matched cohorts, in total, by imaging categories, and in subpopulations of stroke, back pain, and joint pain. MRI use in the nonimplant group over the 4‐year period was extrapolated out to 10 years for ICD‐indicated patients. Results A cohort of 18,770 matched patients were identified; average age 65.5 ± 13.38 and 21.9% female. ICD patients had significantly less MRI imaging (0.23 0.70 SD vs. 0.00 0.08 SD, P < 0.0001) than nonimplant patients. Among patients with records of stroke/transient ischemic attack (TIA) (ICD 5%, nonimplant 4%) and accompanying diagnostic imaging, 44% of nonimplant patients underwent MRI vs. 1% of ICD patients (P < 0.0001). Forecast models estimated that 53% to 64% of ICD‐eligible patients may require an MRI within 10 years. Conclusion MRI utilization is lower in ICD patients compared to nonimplant patients, yet the burden of incident stroke/TIA, back, and joint pain suggests an unmet need for MR‐conditional devices. J. MAGN. RESON. IMAGING 2016;43:115–127. PMID:26118943

  12. Going the Distance: Taking a Diagnostic Imaging Program to Frontier and Rural Oregon

    ERIC Educational Resources Information Center

    Malosh, Ann; Mallory, Stacy; Olson, Marcene

    2009-01-01

    The Grow Your Own diagnostic imaging program is a public/private collaborative venture involving the efforts of an array of community colleges, employers, workforce, and educational partners throughout Oregon. This statewide Community College Partnership delivers diagnostic imaging education to Oregon's rural communities via distributed learning…

  13. Research Priorities in the Utilization and Interpretation of Diagnostic Imaging: Education, Assessment, and Competency.

    PubMed

    Lewiss, Resa E; Chan, Wilma; Sheng, Alexander Y; Soto, Jorge; Castro, Alexandra; Meltzer, Andrew C; Cherney, Alan; Kumaravel, Manickam; Cody, Dianna; Chen, Esther H

    2015-12-01

    The appropriate selection and accurate interpretation of diagnostic imaging is a crucial skill for emergency practitioners. To date, the majority of the published literature and research on competency assessment comes from the subspecialty of point-of-care ultrasound. A group of radiologists, physicists, and emergency physicians convened at the 2015 Academic Emergency Medicine consensus conference to discuss and prioritize a research agenda related to education, assessment, and competency in ordering and interpreting diagnostic imaging. A set of questions for the continued development of an educational curriculum on diagnostic imaging for trainees and competency assessment using specific assessment methods based on current best practices was delineated. The research priorities were developed through an iterative consensus-driven process using a modified nominal group technique that culminated in an in-person breakout session. The four recommendations are: 1) develop a diagnostic imaging curriculum for emergency medicine (EM) residency training; 2) develop, study, and validate tools to assess competency in diagnostic imaging interpretation; 3) evaluate the role of simulation in education, assessment, and competency measures for diagnostic imaging; 4) study is needed regarding the American College of Radiology Appropriateness Criteria, an evidence-based peer-reviewed resource in determining the use of diagnostic imaging, to maximize its value in EM. In this article, the authors review the supporting reliability and validity evidence and make specific recommendations for future research on the education, competency, and assessment of learning diagnostic imaging. © 2015 by the Society for Academic Emergency Medicine.

  14. Diagnostic imaging capabilities of the Ocelot -Optical Coherence Tomography System, ex-vivo evaluation and clinical relevance.

    PubMed

    Dohad, Suhail; Shao, John; Cawich, Ian; Kankaria, Manish; Desai, Arjun

    2015-11-18

    Optical coherence tomography (OCT) is a high-resolution sub-surface imaging modality using near-infrared light to provide accurate and high contrast intra-vascular images. This enables accurate assessment of diseased arteries before and after intravascular intervention. This study was designed to corroborate diagnostic imaging equivalence between the Ocelot and the Dragonfly OCT systems with regards to the intravascular features that are most important in clinical management of patients with atherosclerotic vascular disease. These intravascular features were then corroborated in vivo during treatment of peripheral arterial disease (PAD) pathology using the Ocelot catheter. In order to compare the diagnostic information obtained by Ocelot (Avinger Inc., Redwood City, CA) and Dragonfly (St. Jude Medical, Minneapolis, MN) OCT systems, we utilized ex-vivo preparations of arterial segments. Ocelot and Dragonfly catheters were inserted into identical cadaveric femoral peripheral arteries for image acquisition and interpretation. Three independent physician interpreters assessed the images to establish accuracy and sensitivity of the diagnostic information. Histologic evaluation of the corresponding arterial segments provided the gold standard for image interpretation. In vivo clinical images were obtained during therapeutic interventions that included crossing of peripheral chronic total occlusions (CTOs) using the Ocelot catheter. Strong concordance was demonstrated when matching image characteristics between both OCT systems and histology. The Dragonfly and Ocelot system's vessel features were interpreted with high sensitivity (91.1-100%) and specificity (86.7-100%). Inter-observer concordance was documented with excellent correlation across all vessel features. The clinical benefit that the Ocelot OCT system provided was demonstrated by comparable procedural images acquired at the point of therapy. The study demonstrates equivalence of image acquisition and consistent

  15. Incidental findings in imaging diagnostic tests: a systematic review

    PubMed Central

    Lumbreras, B; Donat, L; Hernández-Aguado, I

    2010-01-01

    The objective of this review is to summarise the available evidence on the frequency and management of incidental findings in imaging diagnostic tests. Original articles were identified by a systematic search of the MEDLINE, EMBASE and Cochrane Library Plus databases using appropriate medical headings. Extracted variables were study design; sample size; type of imaging test; initial diagnosis; frequency and location of incidental findings; whether clinical follow-up was performed; and whether a definitive diagnosis was made. Study characteristics were assessed by one reviewer and checked by a second reviewer. Any disagreement was solved by consensus. The relationship between the frequency of incidental findings and the study characteristics was assessed using a one-way ANOVA test, as was the frequency of follow-up of incidental findings and the frequency of confirmation. 251 potentially relevant abstracts were identified and 44 articles were finally included in the review. Overall, the mean frequency of incidental findings was 23.6% (95% confidence interval (CI) 15.8–31.3%). The frequency of incidental findings was higher in studies involving CT technology (mean 31.1%, 95% CI 20.1–41.9%), in patients with an unspecific initial diagnosis (mean 30.5, 95% CI 0–81.6) and when the location of the incidental findings was unspecified (mean 33.9%, 95% CI 18.1–49.7). The mean frequency of clinical follow-up was 64.5% (95% CI 52.9–76.1%) and mean frequency of clinical confirmation was 45.6% (95% CI 32.1–59.2%). Although the optimal strategy for the management of these abnormalities is still unclear, it is essential to be aware of the low clinical confirmation in findings of moderate and major importance. PMID:20335439

  16. High-sensitivity hyperspectral imager for biomedical video diagnostic applications

    NASA Astrophysics Data System (ADS)

    Leitner, Raimund; Arnold, Thomas; De Biasio, Martin

    2010-04-01

    Video endoscopy allows physicians to visually inspect inner regions of the human body using a camera and only minimal invasive optical instruments. It has become an every-day routine in clinics all over the world. Recently a technological shift was done to increase the resolution from PAL/NTSC to HDTV. But, despite a vast literature on invivo and in-vitro experiments with multi-spectral point and imaging instruments that suggest that a wealth of information for diagnostic overlays is available in the visible spectrum, the technological evolution from colour to hyper-spectral video endoscopy is overdue. There were two approaches (NBI, OBI) that tried to increase the contrast for a better visualisation by using more than three wavelengths. But controversial discussions about the real benefit of a contrast enhancement alone, motivated a more comprehensive approach using the entire spectrum and pattern recognition algorithms. Up to now the hyper-spectral equipment was too slow to acquire a multi-spectral image stack at reasonable video rates rendering video endoscopy applications impossible. Recently, the availability of fast and versatile tunable filters with switching times below 50 microseconds made an instrumentation for hyper-spectral video endoscopes feasible. This paper describes a demonstrator for hyper-spectral video endoscopy and the results of clinical measurements using this demonstrator for measurements after otolaryngoscopic investigations and thorax surgeries. The application investigated here is the detection of dysplastic tissue, although hyper-spectral video endoscopy is of course not limited to cancer detection. Other applications are the detection of dysplastic tissue or polyps in the colon or the gastrointestinal tract.

  17. Differential diagnostic features of the radionuclide scrotal image.

    PubMed

    Mishkin, F S

    1977-01-01

    Differential diagnosis of scrotal lesions is aided by correlating radionuclide images with clinical findings. Subacute torsion is associated with peripheral hyperemia and can be mistaken for an inflammatory process; however, in a review of 128 studies, torsion and orchiectomy were the only processes encountered which had a center truly devoid of activity on the tissue phase compared to the normal side. Other lesions such as acute inflammation, abscess, hematoma, and hemorrhagic tumor may superficially appear to lack central activity but invariably contain at least as much activity when compared to the normal side.

  18. Readout-segmented echo-planar diffusion-weighted imaging in the assessment of orbital tumors: comparison with conventional single-shot echo-planar imaging in image quality and diagnostic performance.

    PubMed

    Xu, Xiaoquan; Wang, Yanjun; Hu, Hao; Su, Guoyi; Liu, Hu; Shi, Haibin; Wu, Feiyun

    2017-01-01

    Background Readout-segmented echo-planar imaging (RS-EPI) could improve the imaging quality of diffusion-weighted imaging (DWI) in various organs. However, whether it could improve the imaging quality and diagnostic performance for the patients with orbital tumors is still unknown. Purpose To compare the image quality and diagnostic performance of RS-EPI DWI with that of conventional single-shot EPI (SS-EPI) DWI in patients with orbital tumors. Material and Methods SS-EPI and RS-EPI DW images of 32 patients with pathologically diagnosed orbital tumors were retrospectively analyzed. Qualitative imaging parameters (imaging sharpness, geometric distortion, ghosting artifacts, and overall imaging quality) and quantitative imaging parameters (apparent diffusion coefficient [ADC], signal-to-noise ratio [SNR], contrast, and contrast-to-noise ratio [CNR]) were assessed by two independent radiologists, and compared between SS-EPI and RS-EPI DWI. Receiver operating characteristic curves were used to determine the diagnostic value of ADC in differentiating malignant from benign orbital tumors. Results RS-EPI DW imaging produced less geometric distortion and ghosting artifacts, and better imaging sharpness and overall imaging quality than SS-EPI DWI (for all, P < 0.001). Meanwhile, RS-EPI DWI produced significantly lower SNR ( P < 0.001) and ADC ( P < 0.001), and higher contrast ( P < 0.001) than SS-EPI DWI, while producing no difference in CNR ( P = 0.137). There was no significant difference on the diagnostic performance between SS-EPI and RS-EPI DWI, when using ADC as the differentiating index ( P = 0.529). Conclusion Compared with SS-EPI, RS-EPI DWI provided significantly better imaging quality and comparable diagnostic performance in differentiating malignant from benign orbital tumors.

  19. Diagnostic Imaging in Flames with Instantaneous Planar Coherent Raman Spectroscopy.

    PubMed

    Bohlin, A; Kliewer, C J

    2014-04-03

    Spatial mapping of temperature and molecular species concentrations is vitally important in studies of gaseous chemically reacting flows. Temperature marks the evolution of heat release and energy transfer, while species concentration gradients provide critical information on mixing and chemical reaction. Coherent anti-Stokes Raman spectroscopy (CARS) was pioneered in measurements of such processes almost 40 years ago and is authoritative in terms of the accuracy and precision it may provide. While a reacting flow is fully characterized in three-dimensional space, a limitation of CARS has been its applicability as a point-wise measurement technique, motivating advancement toward CARS imaging, and attempts have been made considering one-dimensional probing. Here, we report development of two-dimensional CARS, with the first diagnostics of a planar field in a combusting flow within a single laser pulse, resulting in measured isotherms ranging from 450 K up to typical hydrocarbon flame temperatures of about 2000 K with chemical mapping of O2 and N2.

  20. Strategic planning in diagnostic imaging: meeting the challenge.

    PubMed

    Lexa, Frank J

    2008-02-01

    The 21st century has raised new and significant challenges to the practice of diagnostic imaging. Radiologists will have to navigate a difficult path as they face threats from disruptive technologies, adverse demographic changes, pressures to limit reimbursement both from the public and from the private sectors, increased domestic and crossborder competition, and many others. Success in these trying times will require greater attention to strategic planning if we are to thrive and survive in radiology. Strategic planning and tactical implementation methodologies were reviewed, from Sun Tzu to the present day, for applicability to the needs of modern radiology groups. A framework for developing and implementing strategic plans was constructed to assist radiology leaders and groups in considering the spectrum of tasks, from gathering intelligence, to developing scenarios, to implementing and evaluating tactical plans. Strategy and tactics are too important to be ignored or left to others. They need to be core activities for all radiology leaders. Frameworks can be used to help in providing structure and rigour to strategic planning efforts at the department and group level.

  1. Advanced imaging systems for diagnostic investigations applied to Cultural Heritage

    NASA Astrophysics Data System (ADS)

    Peccenini, E.; Albertin, F.; Bettuzzi, M.; Brancaccio, R.; Casali, F.; Morigi, M. P.; Petrucci, F.

    2014-12-01

    The diagnostic investigations are an important resource in the studies on Cultural Heritage to enhance the knowledge on execution techniques, materials and conservation status of a work of art. In this field, due to the great historical and artistic value of the objects, preservation is the main concern; for this reason, new technological equipment has been designed and developed in the Physics Departments of the Universities of Ferrara and Bologna to enhance the non-invasive approach to the study of pictorial artworks and other objects of cultural interest. Infrared (IR) reflectography, X-ray radiography and computed tomography (CT), applied to works of art, are joined by the same goal: to get hidden information on execution techniques and inner structure pursuing the non-invasiveness of the methods, although using different setup and physical principles. In this work transportable imaging systems to investigate large objects in museums and galleries are presented. In particular, 2D scanning devices for IR reflectography and X-ray radiography, CT systems and some applications to the Cultural Heritage are described.

  2. Value of exercise thallium-201 imaging in patients with diagnostic and nondiagnostic exercise electrocardiograms

    SciTech Connect

    Iskandrian, A.S.; Segal, B.L.

    1981-08-01

    The role of exercise imaging with thallium-201 in the evaluation of patients suspected of having coronary artery disease was studied in 194 patients undergoing diagnostic coronary arteriography. Ninety-eight patients had 70 percent or more narrowing of one or more coronary vessels and 96 patients had either no or insignificant coronary artery disease. One hundren twenty-three of the 194 patients had conclusive treadmill exercise electrocardiograms (either positive or negative), and 71 had inconclusive exercise electrocardiograms. The specificity of exercise imaging (97 percent) was higher than that of exercise electrocardiograms (86 percent, p less than 0.02). The specificity of both tests combined was not significantly different from that of exercise electrocardiograms alone. The sensitivity (79 percent) and specificity (95 percent) of exercise imaging were not significantly different in patients with inconclusive exercise electrocardiograms when compared with those in patients whose exercise electrocardiograms were conclusive. These data indicate that exercise imaging is sensitive and specific in diagnosing coronary artery disease in the presence of diagnostic as well as nondiagnostic exercise electrocardiograms and that propranolol therapy does not affect the results.

  3. Image quality, radiation dose and diagnostic accuracy of 70 kVp whole brain volumetric CT perfusion imaging: a preliminary study.

    PubMed

    Fang, Xiao Kun; Ni, Qian Qian; Schoepf, U Joseph; Zhou, Chang Sheng; Chen, Guo Zhong; Luo, Song; Fuller, Stephen R; De Cecco, Carlo N; Zhang, Long Jiang; Lu, Guang Ming

    2016-11-01

    To evaluate image quality and diagnostic accuracy for acute infarct detection and radiation dose of 70 kVp whole brain CT perfusion (CTP) and CT angiography (CTA) reconstructed from CTP source data. Patients were divided into three groups (n = 50 each): group A, 80 kVp, 21 scanning time points; groups B, 70 kVp, 21 scanning time points; group C, 70 kVp, 17 scanning time points. Objective and subjective image quality of CTP and CTA were compared. Diagnostic accuracy for detecting acute infarct and cerebral artery stenosis ≥ 50 % was calculated for CTP and CTA with diffusion weighted imaging and digital subtraction angiography as reference standards. Effective radiation dose was compared. There were no differences in any perfusion parameter value between three groups (P > 0.05). No difference was found in subjective image quality between three groups (P > 0.05). Diagnostic accuracy for detecting acute infarct and vascular stenosis showed no difference between three groups (P > 0.05). Compared with group A, radiation doses of groups B and C were decreased by 28 % and 37 % (both P < 0.001), respectively. Compared with 80 kVp protocol, 70 kVp brain CTP allows comparable vascular and perfusion assessment and lower radiation dose while maintaining high diagnostic accuracy in detecting acute infarct. • 70 kVp whole brain CTP can provide diagnostic image quality. • 70 kVp CTP diagnostic accuracy was maintained vs. 80 kVp protocol. • 70 kVp CTP radiation doses were lower than 80 kVp protocol.

  4. Non-linear multimodal imaging for disease diagnostics and treatment monitoring

    NASA Astrophysics Data System (ADS)

    Bocklitz, Thomas; Schmitt, Michael; Lukić, Aleksandar; Heuke, Sandro; Chernavskaia, Olga; Meyer, Tobias; Popp, Jürgen

    2017-04-01

    Molecular imaging modalities, like multimodal imaging, e.g. the combination of coherent-anti-Stokes Raman scattering (CARS), second-harmonic generation (SHG) and two-photon-excited fluorescence (TPEF), feature a unique potential for disease diagnostics and treatment monitoring. In order to use the full potential of multi-modal imaging for diagnostic tasks powerful image analysis methods are necessary, which translate the physical measurements into medical meaningful information. This translation process requires standardization, correction procedures and statistical models like regression or classification models. With the help of these techniques medical relevant information can be extracted and used for the diagnostics of cancer or inflammation related diseases.

  5. Optical coherence tomography: influence of contrast concentration on image quality and diagnostic confidence.

    PubMed

    Blachutzik, Florian; Achenbach, Stephan; Nef, Holger; Hamm, Christian; Dörr, Oliver; Boeder, Niklas; Marwan, Mohamed; Tröbs, Monique; Schneider, Reinhard; Röther, Jens; Schlundt, Christian

    2016-11-09

    OCT requires intracoronary injection of contrast agent to remove blood from the coronary lumen during data acquisition, which is a possible limitation of this method. Aim of this study was to analyze the influence of iodine concentration on image quality and diagnostic certainty of optical coherence tomography (OCT). OCT sequences acquired using contrast agent with a reduced concentration of 150 mg iodine/ml and a standard concentration of 350 mg iodine/ml were analyzed. Cross-sectional images with a spacing of 10 mm were evaluated regarding image quality and diagnostic confidence. A total of 67 OCT sequences acquired in 24 patients were analyzed. 31 sequences were acquired using contrast agent with a concentration of 150 mg iodine/ml and 36 sequences with a concentration of 350 mg iodine/ml. The percentage of remaining blood streaks in the cross sections was significantly lower for 350 mg iodine/ml compared to 150 mg iodine/ml (19 ± 21 vs. 34 ± 26%, p = 0.013). Contrast with 350 mg iodine/ml showed a significantly higher percentage of completely flushed pullback length as compared to 150 mg iodine/ml (78 ± 24 vs. 58 ± 27%, p = 0.004). Diagnostic certainty was significantly higher for 350 mg iodine/ml than for 150 mg iodine/ml (Likert scale average 1.4 ± 0.7 vs. 2.1 ± 1.2, p < 0.001; Likert scale: 1 = absolutely confident, 2 = confident with slight doubts, 3 = doubtful/not confident, 4 = non-diagnostic). Regarding image quality and diagnostic certainty, contrast agent with a concentration of 350 mg iodine/ml is superior to 150 mg iodine/ml.

  6. Optical diagnostics for turbulent and multiphase flows: Particle image velocimetry and photorefractive optics

    SciTech Connect

    O`Hern, T.J.; Torczynski, J.R.; Shagam, R.N.; Blanchat, T.K.; Chu, T.Y.; Tassin-Leger, A.L.; Henderson, J.A.

    1997-01-01

    This report summarizes the work performed under the Sandia Laboratory Directed Research and Development (LDRD) project ``Optical Diagnostics for Turbulent and Multiphase Flows.`` Advanced optical diagnostics have been investigated and developed for flow field measurements, including capabilities for measurement in turbulent, multiphase, and heated flows. Particle Image Velocimetry (PIV) includes several techniques for measurement of instantaneous flow field velocities and associated turbulence quantities. Nonlinear photorefractive optical materials have been investigated for the possibility of measuring turbulence quantities (turbulent spectrum) more directly. The two-dimensional PIV techniques developed under this LDRD were shown to work well, and were compared with more traditional laser Doppler velocimetry (LDV). Three-dimensional PIV techniques were developed and tested, but due to several experimental difficulties were not as successful. The photorefractive techniques were tested, and both potential capabilities and possible problem areas were elucidated.

  7. The Reproducibility of Changes in Diagnostic Figures of Merit Across Laboratory and Clinical Imaging Reader Studies.

    PubMed

    Samuelson, Frank W; Abbey, Craig K

    2017-06-27

    In this paper we examine which comparisons of reading performance between diagnostic imaging systems made in controlled retrospective laboratory studies may be representative of what we observe in later clinical studies. The change in a meaningful diagnostic figure of merit between two diagnostic modalities should be qualitatively or quantitatively comparable across all kinds of studies. In this meta-study we examine the reproducibility of relative measures of sensitivity, false positive fraction (FPF), area under the receiver operating characteristic (ROC) curve, and expected utility across laboratory and observational clinical studies for several different breast imaging modalities, including screen film mammography, digital mammography, breast tomosynthesis, and ultrasound. Across studies of all types, the changes in the FPFs yielded very small probabilities of having a common mean value. The probabilities of relative sensitivity being the same across ultrasound and tomosynthesis studies were low. No evidence was found for different mean values of relative area under the ROC curve or relative expected utility within any of the study sets. The comparison demonstrates that the ratios of areas under the ROC curve and expected utilities are reproducible across laboratory and clinical studies, whereas sensitivity and FPF are not. Published by Elsevier Inc.

  8. Diagnostic accuracy of new handheld echocardiography with Doppler and harmonic imaging properties.

    PubMed

    Borges, Adrian Constantin; Knebel, Fabian; Walde, Torsten; Sanad, Wasiem; Baumann, Gert

    2004-03-01

    The first generation of handheld echocardiography devices was evaluated with divergent results because of inherent technical limitations. New handheld devices with continuous/pulsed wave Doppler and tissue harmonic imaging were introduced recently. In this study, comparisons were drawn among standard echocardiography, invasively measured systolic pulmonary artery pressure, and these new devices. We sought to evaluate new handheld echocardiography and its diagnostic accuracy compared with standard echocardiography. Two consecutive echocardiographic examinations were performed by experienced and independent examiners using handheld and standard echocardiography. Systolic pulmonary artery pressure was measured by Swan-Ganz catheter. In all, 177 (56.2%) patients had normal cardiac function; 138 (43.8%) had underlying cardiac pathology. Handheld echocardiography had an overall agreement of 94.8% and kappa of 0.89 to detect the main echocardiographic finding. Handheld echocardiography detected valve disease with an agreement of 96.7% and kappa of 0.93; global left ventricular function was assessed correctly in 85.6% of cases. Pericardial effusion was diagnosed with an agreement of 91.2%. Dyssynergy was found by handheld echocardiography with an agreement of 95.4% and kappa value of 0.88. Systolic pulmonary artery pressure measured by handheld echocardiography and Swan-Ganz catheter had a correlation of 0.97. This study demonstrates the high diagnostic accuracy of handheld devices with continuous/pulsed wave Doppler and harmonic imaging, and that these devices broaden the diagnostic spectrum while allowing for enhanced mobility in everyday clinical applications.

  9. Opto-acoustic image fusion technology for diagnostic breast imaging in a feasibility study

    NASA Astrophysics Data System (ADS)

    Zalev, Jason; Clingman, Bryan; Herzog, Don; Miller, Tom; Ulissey, Michael; Stavros, A. T.; Oraevsky, Alexander; Lavin, Philip; Kist, Kenneth; Dornbluth, N. C.; Otto, Pamela

    2015-03-01

    Functional opto-acoustic (OA) imaging was fused with gray-scale ultrasound acquired using a specialized duplex handheld probe. Feasibility Study findings indicated the potential to more accurately characterize breast masses for cancer than conventional diagnostic ultrasound (CDU). The Feasibility Study included OA imagery of 74 breast masses that were collected using the investigational Imagio® breast imaging system. Superior specificity and equal sensitivity to CDU was demonstrated, suggesting that OA fusion imaging may potentially obviate the need for negative biopsies without missing cancers in a certain percentage of breast masses. Preliminary results from a 100 subject Pilot Study are also discussed. A larger Pivotal Study (n=2,097 subjects) is underway to confirm the Feasibility Study and Pilot Study findings.

  10. DIAGNOSTIC IMAGING IN A DIRECT-ACCESS SPORTS PHYSICAL THERAPY CLINIC: A 2-YEAR RETROSPECTIVE PRACTICE ANALYSIS.

    PubMed

    Crowell, Michael S; Dedekam, Erik A; Johnson, Michael R; Dembowski, Scott C; Westrick, Richard B; Goss, Donald L

    2016-10-01

    While advanced diagnostic imaging is a large contributor to the growth in health care costs, direct-access to physical therapy is associated with decreased rates of diagnostic imaging. No study has systematically evaluated with evidence-based criteria the appropriateness of advanced diagnostic imaging, including magnetic resonance imaging (MRI), when ordered by physical therapists. The primary purpose of this study was to describe the appropriateness of magnetic resonance imaging (MRI) or magnetic resonance arthrogram (MRA) exams ordered by physical therapists in a direct-access sports physical therapy clinic. Retrospective observational study of practice. Greater than 80% of advanced diagnostic imaging orders would have an American College of Radiology (ACR) Appropriateness Criteria rating of greater than 6, indicating an imaging order that is usually appropriate. A 2-year retrospective analysis identified 108 MRI/MRA examination orders from four physical therapists. A board-certified radiologist determined the appropriateness of each order based on ACR appropriateness criteria. The principal investigator and co-investigator radiologist assessed agreement between the clinical diagnosis and MRI/surgical findings. Knee (31%) and shoulder (25%) injuries were the most common. Overall, 55% of injuries were acute. The mean ACR rating was 7.7; scores from six to nine have been considered appropriate orders and higher ratings are better. The percentage of orders complying with ACR appropriateness criteria was 83.2%. Physical therapist's clinical diagnosis was confirmed by MRI/MRA findings in 64.8% of cases and was confirmed by surgical findings in 90% of cases. Physical therapists providing musculoskeletal primary care in a direct-access sports physical therapy clinic appropriately ordered advanced diagnostic imaging in over 80% of cases. Future research should prospectively compare physical therapist appropriateness and utilization to other groups of providers and

  11. DIAGNOSTIC IMAGING IN A DIRECT-ACCESS SPORTS PHYSICAL THERAPY CLINIC: A 2-YEAR RETROSPECTIVE PRACTICE ANALYSIS

    PubMed Central

    Dedekam, Erik A.; Johnson, Michael R.; Dembowski, Scott C.; Westrick, Richard B.; Goss, Donald L.

    2016-01-01

    Background While advanced diagnostic imaging is a large contributor to the growth in health care costs, direct-access to physical therapy is associated with decreased rates of diagnostic imaging. No study has systematically evaluated with evidence-based criteria the appropriateness of advanced diagnostic imaging, including magnetic resonance imaging (MRI), when ordered by physical therapists. The primary purpose of this study was to describe the appropriateness of magnetic resonance imaging (MRI) or magnetic resonance arthrogram (MRA) exams ordered by physical therapists in a direct-access sports physical therapy clinic. Study Design Retrospective observational study of practice. Hypothesis Greater than 80% of advanced diagnostic imaging orders would have an American College of Radiology (ACR) Appropriateness Criteria rating of greater than 6, indicating an imaging order that is usually appropriate. Methods A 2-year retrospective analysis identified 108 MRI/MRA examination orders from four physical therapists. A board-certified radiologist determined the appropriateness of each order based on ACR appropriateness criteria. The principal investigator and co-investigator radiologist assessed agreement between the clinical diagnosis and MRI/surgical findings. Results Knee (31%) and shoulder (25%) injuries were the most common. Overall, 55% of injuries were acute. The mean ACR rating was 7.7; scores from six to nine have been considered appropriate orders and higher ratings are better. The percentage of orders complying with ACR appropriateness criteria was 83.2%. Physical therapist's clinical diagnosis was confirmed by MRI/MRA findings in 64.8% of cases and was confirmed by surgical findings in 90% of cases. Conclusions Physical therapists providing musculoskeletal primary care in a direct-access sports physical therapy clinic appropriately ordered advanced diagnostic imaging in over 80% of cases. Future research should prospectively compare physical therapist

  12. A randomized trial comparing the diagnostic yield of rigid and semirigid thoracoscopy in undiagnosed pleural effusions.

    PubMed

    Dhooria, Sahajal; Singh, Navneet; Aggarwal, Ashutosh N; Gupta, Dheeraj; Agarwal, Ritesh

    2014-05-01

    Thoracoscopic pleural biopsy increases the diagnostic yield of pleural effusions undiagnosed after thoracentesis and is superior to closed pleural biopsy. Medical thoracoscopy can be performed using the rigid thoracoscope or the semirigid thoracoscope (pleuroscope). In this randomized trial, we compare the efficacy and safety of the 2 thoracoscopes. Subjects with undiagnosed exudative pleural effusions were randomly assigned to undergo pleural biopsy with either the rigid or the semirigid thoracoscope. The primary outcome was the diagnostic yield of the procedure, while the secondary outcomes were requirement of sedative/analgesic agents, scar size, biopsy sample size, and the operator's view of the procedure. Of the 145 screened subjects with exudative pleural effusions, 90 were randomized to undergo thoracoscopy with the 2 thoracoscopes (n = 45 each). The diagnostic yield of rigid thoracoscopy was superior to semirigid thoracoscopy (97.8% vs 73.3%, P = .002) on an intention-to-treat analysis but was similar (100% vs 94.3%, P = .18) in those with successful biopsy. The requirement of sedative/analgesic agents was higher in the rigid thoracoscopy arm. The scar size was slightly larger (mean ± SD, 23.1 ± 4 vs 18.7 ± 3.2 mm, P = .0001), whereas the biopsy sample size was distinctly larger in the rigid arm (mean ± SD, 13.9 ± 4.4 vs 4.4 ± 1.4 mm, P = .001). The operator-rated visual analog scale score for the ease of taking a biopsy sample was significantly higher with the rigid instrument (mean ± SD, visual analog scale 86 ± 12 vs 79 ± 12 mm, P = .01), while the quality of image was superior in the semirigid arm (mean ± SD, visual analog scale 88 ± 7 vs 92 ± 5 mm, P = .002). The number of complications were similar in the 2 groups. Rigid thoracoscopy was found to be superior to semirigid thoracoscopy overall, but the diagnostic yield was similar if pleural biopsy could be successfully performed. Due to the small sample size, a larger study is required to

  13. Investigating the link between radiologists' gaze, diagnostic decision, and image content.

    PubMed

    Tourassi, Georgia; Voisin, Sophie; Paquit, Vincent; Krupinski, Elizabeth

    2013-01-01

    To investigate machine learning for linking image content, human perception, cognition, and error in the diagnostic interpretation of mammograms. Gaze data and diagnostic decisions were collected from three breast imaging radiologists and three radiology residents who reviewed 20 screening mammograms while wearing a head-mounted eye-tracker. Image analysis was performed in mammographic regions that attracted radiologists' attention and in all abnormal regions. Machine learning algorithms were investigated to develop predictive models that link: (i) image content with gaze, (ii) image content and gaze with cognition, and (iii) image content, gaze, and cognition with diagnostic error. Both group-based and individualized models were explored. By pooling the data from all readers, machine learning produced highly accurate predictive models linking image content, gaze, and cognition. Potential linking of those with diagnostic error was also supported to some extent. Merging readers' gaze metrics and cognitive opinions with computer-extracted image features identified 59% of the readers' diagnostic errors while confirming 97.3% of their correct diagnoses. The readers' individual perceptual and cognitive behaviors could be adequately predicted by modeling the behavior of others. However, personalized tuning was in many cases beneficial for capturing more accurately individual behavior. There is clearly an interaction between radiologists' gaze, diagnostic decision, and image content which can be modeled with machine learning algorithms.

  14. Pott's Spine: Diagnostic Imaging Modalities and Technology Advancements

    PubMed Central

    Ansari, Sajid; Amanullah, Md. Farid; Ahmad, Kaleem; Rauniyar, Raj Kumar

    2013-01-01

    Spinal tuberculosis (TB) or Pott's spine is the commonest extrapulmonary manifestation of TB. It spreads through hematogenous route. Clinically, it presents with constitutional symptoms, back pain, tenderness, paraplegia or paraparesis, and kyphotic or scoliotic deformities. Pott's spine accounts for 2% of all cases of TB, 15% of extrapulmonary, and 50% of skeletal TB. The paradiscal, central, anterior subligamentous, and neural arch are the common vertebral lesions. Thoracic vertebrae are commonly affected followed by lumbar and cervical vertebrae. Plain radiographs are usually the initial investigation in spinal TB. For a radiolucent lesion to be apparent on a plain radiograph there should be 30% of bone mineral loss. Computed tomographic scanning provides much better bony detail of irregular lytic lesions, sclerosis, disc collapse, and disruption of bone circumference than plain radiograph. Magnetic resonance imaging (MRI) is the best diagnostic modality for Pott's spine and is more sensitive than other modalities. MRI frequently demonstrates disc collapse/destruction, cold abscess, vertebral wedging/collapse, marrow edema, and spinal deformities. Ultrasound and computed tomographic guided needle aspiration or biopsy is the technique for early histopathological diagnosis. Recently, the coexistence of human immunodeficiency virus infections and TB has been increased globally. In recent years, diffusion-weighted MRI (DW-MRI) and apparent diffusion coefficient values in combination with MRI are used to some extent in the diagnosis of spinal TB. We have reviewed related literature through internet. The terms searched on Google scholar and PubMed are TB, extrapulmonary TB, skeletal TB, spinal TB, Pott's spine, Pott's paraplegia, MRI, and computed tomography (CT). PMID:24020048

  15. [Comparative study of different diagnostic methods in pulmonary alveolitis].

    PubMed

    Makhmudova, S Iu

    2009-05-01

    To evaluate and analyze, clinical and roentgenological manifestations of extrinsic allergic alveolitis (EAA) and idiopathic fibrosing alveolitis (IFA) 89 patients underwent bronchoscopy survey and functional test of lungs. Average age of patients was 38,3+/-5,8. Among examined 89 patients 31 (34,8%) patients were poultry farmers, 30 (33,7%) - millers, and 28 (31,5%) - tobacco-growers. EAA was found among 22 poultry farmers, 19 tobacco-growers, and 19 millers. IFA was found among 11 millers, 9 tobacco-growers and 9 poultry farmers. Acute respiratory disease (ARD) was found among 58 patients; 38 patients suffer from lung diseases. Control group consisted of 20 healthy people. Along with general blood analysis, all patients underwent - roentgenological analysis of thorax in two shifts. Recent studies show that CT lung screening is more sensitive than standard lung screening methods in detecting lung disease. Comparative analysis allowed concluding that Real-Time CT method is the most effective. CT lung screening is more sensitive than standard lung screening methods in detecting lung diseases.

  16. Comparing the diagnostic utility of sacroiliac spectral CT and MRI in axial spondyloarthritis

    PubMed Central

    Zhang, Ping; Yu, Kai Hu; Guo, Rui Min; Ran, Jun; Liu, Yao; Morelli, John; Runge, Val A

    2016-01-01

    Objective: To compare the clinical value of sacroiliac spectral CT and MRI in diagnosing axial spondyloarthritis (SpA). Methods: 137 patients with low back pain and suspected axial SpA were recruited. 76 patients were diagnosed with axial SpA, and 49 patients were diagnosed with non-specific low back pain (nLBP). Each patient underwent spectral CT and MRI examinations of the sacroiliac joints. Water- and calcium-based material decomposition images were reconstructed for quantitative analysis. The marrow-to-muscle ratios of water and calcium concentrations and short tau inversion recovery (STIR) signal intensity, as well as Hounsfield units in the ilium and sacrum were compared between nLBP and patients with axial SpA. Results: Spectral CT is comparable with MRI for the detection of bone marrow oedema, and it is superior to MRI for detection of osseous sclerosis and erosions. MRI is superior to spectral CT in detecting enthesitis and synovitis. There were statistically significant differences in STIR signal intensity, water concentration and calcium concentration ratios as well as CT values between nLBP and patients with axial SpA (p < 0.05) in the ilium. There was a statistically significant but weak correlation between ratios of water concentration and STIR signal intensity in both the ilium and sacrum (p < 0.05). Overall, the iliac water concentration was most sensitive for detection of patients with SpA. The positive likelihood ratio of the STIR signal intensity ratio was the highest. The diagnostic odds ratio of the calcium concentration ratio was the highest, and its negative likelihood ratio was the lowest. Conclusion: Spectral CT not only depicts findings of chronic sacroiliitis (i.e. bone erosion and sclerosis), but also can detect and quantify the extent of marrow oedema in patients with SpA with activity sacroiliitis. The sensitivity of MRI for diagnosis of early synovitis and enthesitis remains superior. The combination of spectral CT and MRI may

  17. Comparison of different phantoms used in digital diagnostic imaging

    NASA Astrophysics Data System (ADS)

    Bor, Dogan; Unal, Elif; Uslu, Anil

    2015-09-01

    The organs of extremity, chest, skull and lumbar were physically simulated using uniform PMMA slabs with different thicknesses alone and using these slabs together with aluminum plates and air gaps (ANSI Phantoms). The variation of entrance surface air kerma and scatter fraction with X-ray beam qualities was investigated for these phantoms and the results were compared with those measured from anthropomorphic phantoms. A flat panel digital radiographic system was used for all the experiments. Considerable variations of entrance surface air kermas were found for the same organs of different designs, and highest doses were measured for the PMMA slabs. A low contrast test tool and a contrast detail test object (CDRAD) were used together with each organ simulation of PMMA slabs and ANSI phantoms in order to test the clinical image qualities. Digital images of these phantom combinations and anthropomorphic phantoms were acquired in raw and clinically processed formats. Variation of image quality with kVp and post processing was evaluated using the numerical metrics of these test tools and measured contrast values from the anthropomorphic phantoms. Our results indicated that design of some phantoms may not be efficient enough to reveal the expected performance of the post processing algorithms.

  18. Mapping the different methods adopted for diagnostic imaging instruction at medical schools in Brazil

    PubMed Central

    Chojniak, Rubens; Carneiro, Dominique Piacenti; Moterani, Gustavo Simonetto Peres; Duarte, Ivone da Silva; Bitencourt, Almir Galvão Vieira; Muglia, Valdair Francisco; D'Ippolito, Giuseppe

    2017-01-01

    Objective To map the different methods for diagnostic imaging instruction at medical schools in Brazil. Materials and Methods In this cross-sectional study, a questionnaire was sent to each of the coordinators of 178 Brazilian medical schools. The following characteristics were assessed: teaching model; total course hours; infrastructure; numbers of students and professionals involved; themes addressed; diagnostic imaging modalities covered; and education policies related to diagnostic imaging. Results Of the 178 questionnaires sent, 45 (25.3%) were completed and returned. Of those 45 responses, 17 (37.8%) were from public medical schools, whereas 28 (62.2%) were from private medical schools. Among the 45 medical schools evaluated, the method of diagnostic imaging instruction was modular at 21 (46.7%), classic (independent discipline) at 13 (28.9%), hybrid (classical and modular) at 9 (20.0%), and none of the preceding at 3 (6.7%). Diagnostic imaging is part of the formal curriculum at 36 (80.0%) of the schools, an elective course at 3 (6.7%), and included within another modality at 6 (13.3%). Professors involved in diagnostic imaging teaching are radiologists at 43 (95.5%) of the institutions. Conclusion The survey showed that medical courses in Brazil tend to offer diagnostic imaging instruction in courses that include other content and at different time points during the course. Radiologists are extensively involved in undergraduate medical education, regardless of the teaching methodology employed at the institution. PMID:28298730

  19. Mapping the different methods adopted for diagnostic imaging instruction at medical schools in Brazil.

    PubMed

    Chojniak, Rubens; Carneiro, Dominique Piacenti; Moterani, Gustavo Simonetto Peres; Duarte, Ivone da Silva; Bitencourt, Almir Galvão Vieira; Muglia, Valdair Francisco; D'Ippolito, Giuseppe

    2017-01-01

    To map the different methods for diagnostic imaging instruction at medical schools in Brazil. In this cross-sectional study, a questionnaire was sent to each of the coordinators of 178 Brazilian medical schools. The following characteristics were assessed: teaching model; total course hours; infrastructure; numbers of students and professionals involved; themes addressed; diagnostic imaging modalities covered; and education policies related to diagnostic imaging. Of the 178 questionnaires sent, 45 (25.3%) were completed and returned. Of those 45 responses, 17 (37.8%) were from public medical schools, whereas 28 (62.2%) were from private medical schools. Among the 45 medical schools evaluated, the method of diagnostic imaging instruction was modular at 21 (46.7%), classic (independent discipline) at 13 (28.9%), hybrid (classical and modular) at 9 (20.0%), and none of the preceding at 3 (6.7%). Diagnostic imaging is part of the formal curriculum at 36 (80.0%) of the schools, an elective course at 3 (6.7%), and included within another modality at 6 (13.3%). Professors involved in diagnostic imaging teaching are radiologists at 43 (95.5%) of the institutions. The survey showed that medical courses in Brazil tend to offer diagnostic imaging instruction in courses that include other content and at different time points during the course. Radiologists are extensively involved in undergraduate medical education, regardless of the teaching methodology employed at the institution.

  20. Diagnostic performance of fusion of myocardial perfusion imaging (MPI) and computed tomography coronary angiography

    PubMed Central

    Santana, Cesar A.; Garcia, Ernest V.; Faber, Tracy L.; Sirineni, Gopi K. R.; Esteves, Fabio P.; Sanyal, Rupan; Halkar, Raghuveer; Ornelas, Mario; Verdes, Liudmila; Lerakis, Stamatios; Ramos, Julie J.; Aguadé-Bruix, Santiago; Cuéllar, Hugo; Candell-Riera, Jaume; Raggi, Paolo

    2011-01-01

    Background We evaluated the incremental diagnostic value of fusion images of coronary computed tomography angiography (CTA) and myocardial perfusion imaging (MPI) over MPI alone or MPI and CTA side-by-side to identify obstructive coronary artery disease (CAD > 50% stenosis) using invasive coronary angiography (ICA) as the gold standard. Methods 50 subjects (36 men; 56 ± 11 years old) underwent rest-stress MPI and CTA within 12-26 days of each other. CTAs were performed with multi-detector CT-scanners (31 on 64-slice; and 19 on 16-slice). 37 patients underwent ICA while 13 subjects did not because of low (<5%) pre-test likelihood (LLK) of disease. Three blinded readers scored the images in sequential sessions using (1) MPI alone (2) MPI and CTA side-by-side, (3) fused CTA/MPI images. Results One or more critical stenoses during ICA were found in 28 patients and non-critical stenoses were found in 9 patients. MPI, side-by-side MPI-CTA, and fused CTA/MPI showed the same normalcy rate (NR:13/13) in LLK subjects. The fusion technique performed better than MPI and MPI and CTA side-by-side for the presence of CAD in any vessel (overall area under the curve (AUC) for fused images: 0.89; P = .005 vs MPI, P = .04 vs side-by-side MPI-CTA) and for localization of CAD to the left anterior descending coronary artery (AUC: 0.82, P < .001 vs MPI; P = .007 vs side-by-side MPI-CTA). There was a non-significant trend for better detection of multi-vessel disease with fusion. Conclusions Using ICA as the gold standard, fusion imaging provided incremental diagnostic information compared to MPI alone or side-by-side MPI-CTA for the diagnosis of obstructive CAD and for localization of CAD to the left anterior descending coronary artery. PMID:19156478

  1. Technical Note: Method to correlate whole-specimen histopathology of radical prostatectomy with diagnostic MR imaging

    SciTech Connect

    McGrath, Deirdre M. Lee, Jenny; Foltz, Warren D.; Samavati, Navid; Jewett, Michael A. S.; Kwast, Theo van der; Chung, Peter; Ménard, Cynthia; Brock, Kristy K.

    2016-03-15

    Purpose: Validation of MRI-guided tumor boundary delineation for targeted prostate cancer therapy is achieved via correlation with gold-standard histopathology of radical prostatectomy specimens. Challenges to accurate correlation include matching the pathology sectioning plane with the in vivo imaging slice plane and correction for the deformation that occurs between in vivo imaging and histology. A methodology is presented for matching of the histological sectioning angle and position to the in vivo imaging slices. Methods: Patients (n = 4) with biochemical failure following external beam radiotherapy underwent diagnostic MRI to confirm localized recurrence of prostate cancer, followed by salvage radical prostatectomy. High-resolution 3-D MRI of the ex vivo specimens was acquired to determine the pathology sectioning angle that best matched the in vivo imaging slice plane, using matching anatomical features and implanted fiducials. A novel sectioning device was developed to guide sectioning at the correct angle, and to assist the insertion of reference dye marks to aid in histopathology reconstruction. Results: The percentage difference in the positioning of the urethra in the ex vivo pathology sections compared to the positioning in in vivo images was reduced from 34% to 7% through slicing at the best match angle. Reference dye marks were generated, which were visible in ex vivo imaging, in the tissue sections before and after processing, and in histology sections. Conclusions: The method achieved an almost fivefold reduction in the slice-matching error and is readily implementable in combination with standard MRI technology. The technique will be employed to generate datasets for correlation of whole-specimen prostate histopathology with in vivo diagnostic MRI using 3-D deformable registration, allowing assessment of the sensitivity and specificity of MRI parameters for prostate cancer. Although developed specifically for prostate, the method is readily

  2. Technical Note: Method to correlate whole-specimen histopathology of radical prostatectomy with diagnostic MR imaging

    PubMed Central

    McGrath, Deirdre M.; Lee, Jenny; Foltz, Warren D.; Samavati, Navid; Jewett, Michael A. S.; van der Kwast, Theo; Chung, Peter; Ménard, Cynthia; Brock, Kristy K.

    2016-01-01

    Purpose: Validation of MRI-guided tumor boundary delineation for targeted prostate cancer therapy is achieved via correlation with gold-standard histopathology of radical prostatectomy specimens. Challenges to accurate correlation include matching the pathology sectioning plane with the in vivo imaging slice plane and correction for the deformation that occurs between in vivo imaging and histology. A methodology is presented for matching of the histological sectioning angle and position to the in vivo imaging slices. Methods: Patients (n = 4) with biochemical failure following external beam radiotherapy underwent diagnostic MRI to confirm localized recurrence of prostate cancer, followed by salvage radical prostatectomy. High-resolution 3-D MRI of the ex vivo specimens was acquired to determine the pathology sectioning angle that best matched the in vivo imaging slice plane, using matching anatomical features and implanted fiducials. A novel sectioning device was developed to guide sectioning at the correct angle, and to assist the insertion of reference dye marks to aid in histopathology reconstruction. Results: The percentage difference in the positioning of the urethra in the ex vivo pathology sections compared to the positioning in in vivo images was reduced from 34% to 7% through slicing at the best match angle. Reference dye marks were generated, which were visible in ex vivo imaging, in the tissue sections before and after processing, and in histology sections. Conclusions: The method achieved an almost fivefold reduction in the slice-matching error and is readily implementable in combination with standard MRI technology. The technique will be employed to generate datasets for correlation of whole-specimen prostate histopathology with in vivo diagnostic MRI using 3-D deformable registration, allowing assessment of the sensitivity and specificity of MRI parameters for prostate cancer. Although developed specifically for prostate, the method is readily

  3. Broadband coherent anti-Stokes Raman scattering (CARS): a potential tool for atherosclerosis diagnostic imaging

    NASA Astrophysics Data System (ADS)

    Cormier, J.-F.; Ko, A.; Choo-Smith, L.-P.; Werner, J.; Kohlenberg, E.; Hewko, M.; Fréchette, J.; Fortin, M.; Noiseux, I.; Bouchard, J. P.; Gay, David; Desroches, P.; Roy-Moisan, Francois; Bourgault, Marie-Eve; Sowa, M. G.; Vernon, M. L.

    2007-02-01

    Nonlinear optical imaging technologies offer some intriguing medical diagnostic applications. Examples include fast imaging of elastin and collagen distributions in diseased tissues using two-photon fluorescence (TPF) and second harmonic generation (SHG), respectively. The 3D sectioning capabilities and biochemical specificity that enable fast imaging in highly scattering biological media lie at the heart of the appeal of these nonlinear approaches for medical applications. One of these promising nonlinear techniques relies on the resonance enhancement of the third order nonlinear susceptibility by a vibrational mode of a molecule. Coherent Anti-Stokes Raman Scattering (CARS) can provide similar vibrational information as a spontaneous Raman spectrum. The technique has been shown to be orders of magnitude more sensitive than spontaneous Raman, with video rate imaging demonstrated recently. In this work, we investigate the potential use of broadband CARS spectroscopy and CARS imaging for biochemical analysis of arterial tissue. Biochemical imaging data from broadband CARS is compared with spontaneous Raman microspectroscopy. The broadband CARS system comprised of a single femtosecond-laser is presented in detail. Issues related to data analysis, the advantages and current limitations of the CARS technique in biodiagnostics are discussed.

  4. Can we safely diagnose pigmented lesions from stored video images? A diagnostic comparison between clinical examination and stored video images of pigmented lesions removed for histology.

    PubMed

    Jolliffe, V M; Harris, D W; Whittaker, S J

    2001-01-01

    Rapid expansion of communication technology has permitted the clinician to perform a consultation with a patient located at a different site. Assuming adequate diagnostic accuracy, it could theoretically be possible to use telemedical techniques as a triage tool. Images of pigmented lesions sent by the primary care physician could be viewed by the consultant dermatologist, and those with banal lesions spared from attending clinic. Previous studies assessing diagnostic accuracy of images of lesions have used 'face-to-face' diagnoses as the 'gold standard'. We set out to compare diagnostic accuracy of image examination compared with that of clinical examination, using histological examination as the diagnostic benchmark. We found that pigmented lesions may be diagnosed as accurately by stored video image evaluation as by conventional clinical examination. None of the malignant skin tumours was misdiagnosed as benign in either group. Whilst these results are encouraging in terms of the clinical safety of store-and-forward imaging, the inability to examine the whole patient or to palpate the lesions may limit the acceptability of the technique severely. Further evaluation of the cost : benefit ratio of such a system to the health care provider must be undertaken before considering this technique as a potential adjunct to managing outpatient referrals.

  5. Different diagnostic values of imaging parameters to predict pseudoprogression in glioblastoma subgroups stratified by MGMT promoter methylation.

    PubMed

    Yoon, Ra Gyoung; Kim, Ho Sung; Paik, Wooyul; Shim, Woo Hyun; Kim, Sang Joon; Kim, Jeong Hoon

    2017-01-01

    The aim of this study was to determine whether diffusion and perfusion imaging parameters demonstrate different diagnostic values for predicting pseudoprogression between glioblastoma subgroups stratified by O(6)-mythylguanine-DNA methyltransferase (MGMT) promoter methylation status. We enrolled seventy-five glioblastoma patients that had presented with enlarged contrast-enhanced lesions on magnetic resonance imaging (MRI) one month after completing concurrent chemoradiotherapy and undergoing MGMT promoter methylation testing. The imaging parameters included 10 or 90 % histogram cutoffs of apparent diffusion coefficient (ADC10), normalized cerebral blood volume (nCBV90), and initial area under the time signal-intensity curve (IAUC90). The results of the areas under the receiver operating characteristic curve (AUCs) with cross-validation were compared between MGMT methylation and unmethylation groups. MR imaging parameters demonstrated a trend toward higher accuracy in the MGMT promoter methylation group than in the unmethylation group (cross-validated AUCs = 0.70-0.95 and 0.56-0.87, respectively). The combination of MGMT methylation status with imaging parameters improved the AUCs from 0.70 to 0.75-0.90 for both readers in comparison with MGMT methylation status alone. The probability of pseudoprogression was highest (95.7 %) when nCBV90 was below 4.02 in the MGMT promoter methylation group. MR imaging parameters could be stronger predictors of pseudoprogression in glioblastoma patients with the methylated MGMT promoter than in patients with the unmethylated MGMT promoter. • The glioblastoma subgroup was stratified according to MGMT promoter methylation status. • Diagnostic values of diffusion and perfusion parameters for predicting pseudoprogression were compared. • Imaging parameters showed higher diagnostic accuracy in the MGMT promoter methylation group. • Imaging parameters were independent to MGMT promoter methylation status for predicting

  6. The accuracy of diagnostic ultrasound imaging for musculoskeletal soft tissue pathology of the extremities: a comprehensive review of the literature.

    PubMed

    Henderson, Rogan E A; Walker, Bruce F; Young, Kenneth J

    2015-01-01

    Musculoskeletal diagnostic ultrasound imaging (MSK-DUSI) has been growing outside the traditional radiology speciality. Increased use of this technology has been reported in several healthcare settings, however an apparent gap in the knowledge of the accuracy of this diagnostic technology indicated a review was warranted. We undertook a structured review of the literature to assess the accuracy of MSK-DUSI for the diagnosis of musculoskeletal soft tissue pathology of the extremities. An electronic search of the National Library of Medicine's PubMed database (1972 to mid-2014) was conducted. All relevant systematic reviews of diagnostic studies, all diagnostic studies published after the date of the latest systematic reviews and relevant diagnostic studies outside the scope the systematic reviews that directly compared the accuracy of MSK-DUSI (the index test) to an appropriate reference standard for the target condition were included. A fundamental appraisal of the methodological quality of studies was completed. The individual sensitivity, specificity and likelihood ratio data were extracted and entered into diagnostic accuracy tables. A total of 207 individual studies were included. The results show that MSK-DUSI has acceptable diagnostic accuracy for a wide spectrum of musculoskeletal conditions of the extremities. However, there is a lack of high quality prospective experimental studies in this area and as such clinicians should interpret the results with some caution due to the potential for overestimation of diagnostic accuracy.

  7. Companion diagnostics and molecular imaging-enhanced approaches for oncology clinical trials.

    PubMed

    Van Heertum, Ronald L; Scarimbolo, Robert; Ford, Robert; Berdougo, Eli; O'Neal, Michael

    2015-01-01

    In the era of personalized medicine, diagnostic approaches are helping pharmaceutical and biotechnology sponsors streamline the clinical trial process. Molecular assays and diagnostic imaging are routinely being used to stratify patients for treatment, monitor disease, and provide reliable early clinical phase assessments. The importance of diagnostic approaches in drug development is highlighted by the rapidly expanding global cancer diagnostics market and the emergent attention of regulatory agencies worldwide, who are beginning to offer more structured platforms and guidance for this area. In this paper, we highlight the key benefits of using companion diagnostics and diagnostic imaging with a focus on oncology clinical trials. Nuclear imaging using widely available radiopharmaceuticals in conjunction with molecular imaging of oncology targets has opened the door to more accurate disease assessment and the modernization of standard criteria for the evaluation, staging, and treatment responses of cancer patients. Furthermore, the introduction and validation of quantitative molecular imaging continues to drive and optimize the field of oncology diagnostics. Given their pivotal role in disease assessment and treatment, the validation and commercialization of diagnostic tools will continue to advance oncology clinical trials, support new oncology drugs, and promote better patient outcomes.

  8. Companion diagnostics and molecular imaging-enhanced approaches for oncology clinical trials

    PubMed Central

    Van Heertum, Ronald L; Scarimbolo, Robert; Ford, Robert; Berdougo, Eli; O’Neal, Michael

    2015-01-01

    In the era of personalized medicine, diagnostic approaches are helping pharmaceutical and biotechnology sponsors streamline the clinical trial process. Molecular assays and diagnostic imaging are routinely being used to stratify patients for treatment, monitor disease, and provide reliable early clinical phase assessments. The importance of diagnostic approaches in drug development is highlighted by the rapidly expanding global cancer diagnostics market and the emergent attention of regulatory agencies worldwide, who are beginning to offer more structured platforms and guidance for this area. In this paper, we highlight the key benefits of using companion diagnostics and diagnostic imaging with a focus on oncology clinical trials. Nuclear imaging using widely available radiopharmaceuticals in conjunction with molecular imaging of oncology targets has opened the door to more accurate disease assessment and the modernization of standard criteria for the evaluation, staging, and treatment responses of cancer patients. Furthermore, the introduction and validation of quantitative molecular imaging continues to drive and optimize the field of oncology diagnostics. Given their pivotal role in disease assessment and treatment, the validation and commercialization of diagnostic tools will continue to advance oncology clinical trials, support new oncology drugs, and promote better patient outcomes. PMID:26392755

  9. Making sure. A comparative micro-analysis of diagnostic instruments in medical practice.

    PubMed

    Schubert, Cornelius

    2011-09-01

    This article conceptualises diagnosis as ongoing practical judgement in medical care. Based on pragmatist and phenomenological considerations of tools in use, it uses a comparative approach to analyse similarities and differences in the use of diagnostic technologies. In the first part of the paper, a historical perspective on the innovation of the stethoscope is used to highlight the transformations in diagnostic practices occasioned by novel diagnostic instruments. In the second part of the paper, ethnographic accounts of contemporary anaesthesia are presented in order to sketch out the manifold variations of using diagnostic instruments in daily practice. Both cases are analysed on a micro-analytical level, emphasising the interrelations of bodies, tools and knowledge in concrete situations. The analysis shows how diagnostic instruments become embodied in the perceptual habits of physicians and how diagnosing becomes an ongoing activity in the course of managing an illness trajectory.

  10. Medical physics: some recollections in diagnostic X-ray imaging and therapeutic radiology.

    PubMed

    Gray, J E; Orton, C G

    2000-12-01

    Medical physics has changed dramatically since 1895. There was a period of slow evolutionary change during the first 70 years after Roentgen's discovery of x rays. With the advent of the computer, however, both diagnostic and therapeutic radiology have undergone rapid growth and changes. Technologic advances such as computed tomography and magnetic resonance imaging in diagnostic imaging and three-dimensional treatment planning systems, stereotactic radiosurgery, and intensity modulated radiation therapy in radiation oncology have resulted in substantial changes in medical physics. These advances have improved diagnostic imaging and radiation therapy while expanding the need for better educated and experienced medical physics staff.

  11. Impact of iterative metal artifact reduction on diagnostic image quality in patients with dental hardware.

    PubMed

    Weiß, Jakob; Schabel, Christoph; Bongers, Malte; Raupach, Rainer; Clasen, Stephan; Notohamiprodjo, Mike; Nikolaou, Konstantin; Bamberg, Fabian

    2017-03-01

    Background Metal artifacts often impair diagnostic accuracy in computed tomography (CT) imaging. Therefore, effective and workflow implemented metal artifact reduction algorithms are crucial to gain higher diagnostic image quality in patients with metallic hardware. Purpose To assess the clinical performance of a novel iterative metal artifact reduction (iMAR) algorithm for CT in patients with dental fillings. Material and Methods Thirty consecutive patients scheduled for CT imaging and dental fillings were included in the analysis. All patients underwent CT imaging using a second generation dual-source CT scanner (120 kV single-energy; 100/Sn140 kV in dual-energy, 219 mAs, gantry rotation time 0.28-1/s, collimation 0.6 mm) as part of their clinical work-up. Post-processing included standard kernel (B49) and an iterative MAR algorithm. Image quality and diagnostic value were assessed qualitatively (Likert scale) and quantitatively (HU ± SD) by two reviewers independently. Results All 30 patients were included in the analysis, with equal reconstruction times for iMAR and standard reconstruction (17 s ± 0.5 vs. 19 s ± 0.5; P > 0.05). Visual image quality was significantly higher for iMAR as compared with standard reconstruction (3.8 ± 0.5 vs. 2.6 ± 0.5; P < 0.0001, respectively) and showed improved evaluation of adjacent anatomical structures. Similarly, HU-based measurements of degree of artifacts were significantly lower in the iMAR reconstructions as compared with the standard reconstruction (0.9 ± 1.6 vs. -20 ± 47; P < 0.05, respectively). Conclusion The tested iterative, raw-data based reconstruction MAR algorithm allows for a significant reduction of metal artifacts and improved evaluation of adjacent anatomical structures in the head and neck area in patients with dental hardware.

  12. Diagnostic imaging for chronic plantar heel pain: a systematic review and meta-analysis

    PubMed Central

    2009-01-01

    Background Chronic plantar heel pain (CPHP) is a generalised term used to describe a range of undifferentiated conditions affecting the plantar heel. Plantar fasciitis is reported as the most common cause and the terms are frequently used interchangeably in the literature. Diagnostic imaging has been used by many researchers and practitioners to investigate the involvement of specific anatomical structures in CPHP. These observations help to explain the underlying pathology of the disorder, and are of benefit in forming an accurate diagnosis and targeted treatment plan. The purpose of this systematic review was to investigate the diagnostic imaging features associated with CPHP, and evaluate study findings by meta-analysis where appropriate. Methods Bibliographic databases including Medline, Embase, CINAHL, SportDiscus and The Cochrane Library were searched electronically on March 25, 2009. Eligible articles were required to report imaging findings in participants with CPHP unrelated to inflammatory arthritis, and to compare these findings with a control group. Methodological quality was evaluated by use of the Quality Index as described by Downs and Black. Meta-analysis of study data was conducted where appropriate. Results Plantar fascia thickness as measured by ultrasonography was the most widely reported imaging feature. Meta-analysis revealed that the plantar fascia of CPHP participants was 2.16 mm thicker than control participants (95% CI = 1.60 to 2.71 mm, P < 0.001) and that CPHP participants were more likely to have plantar fascia thickness values greater than 4.0 mm (OR = 105.11, 95% CI = 3.09 to 3577.28, P = 0.01). CPHP participants were also more likely to show radiographic evidence of subcalcaneal spur than control participants (OR = 8.52, 95% CI = 4.08 to 17.77, P < 0.001). Conclusion This systematic review has identified 23 studies investigating the diagnostic imaging appearance of the plantar fascia and inferior calcaneum in people with CPHP

  13. Diagnostic value of the stand-alone synthetic image in digital breast tomosynthesis examinations.

    PubMed

    Garayoa, Julia; Chevalier, Margarita; Castillo, Maria; Mahillo-Fernández, Ignacio; Amallal El Ouahabi, Najim; Estrada, Carmen; Tejerina, Alejandro; Benitez, Olivia; Valverde, Julio

    2017-08-15

    To demonstrate the non-inferiority of synthetic image (SI) mammography versus full-field digital mammography (FFDM) in breast tomosynthesis (DBT) examinations. An observational, retrospective, single-centre, multireader blinded study was performed, using 2384 images to directly compare SI and FFDM based on Breast Imaging Reporting and Data System (BIRADS) categorisation and visibility of radiological findings. Readers had no access to digital breast tomosynthesis slices. Multiple reader, multiple case (MRMC) receiver operating characteristic (ROC) methodology was used to compare the diagnostic performance of SI and FFDM images. The kappa statistic was used to estimate the inter-reader and intra-reader reliability. The area under the ROC curves (AUC) reveals the non-inferiority of SI versus FFDM based on BIRADS categorisation [difference between AUC (ΔAUC), -0.014] and lesion visibility (ΔAUC, -0.001) but the differences were not statistically significant (p=0.282 for BIRADS; p=0.961 for lesion visibility). On average, 77.4% of malignant lesions were detected with SI versus 76.5% with FFDM. Sensitivity and specificity of SI are superior to FFDM for malignant lesions scored as BIRADS 5 and breasts categorised as BIRADS 1. SI is not inferior to FFDM when DBT slices are not available during image reading. SI can replace FFDM, reducing the dose by 45%. • Stand-alone SI demonstrated performance not inferior for lesion visibility as compared to FFDM. • Stand-alone SI demonstrated performance not inferior for lesion BIRADS categorisation as compared to FFDM. • Synthetic images provide important dose savings in breast tomosynthesis examinations.

  14. Diagnostic Imaging in the Medical Support of the Future Missions to the Moon

    NASA Technical Reports Server (NTRS)

    Sargsyan, Ashot E.; Jones, Jeffrey A.; Hamilton, Douglas R.; Dulchavsky, Scott A.; Duncan, J. Michael

    2007-01-01

    This viewgraph presentation is a course that reviews the diagnostic imaging techniques available for medical support on the future moon missions. The educational objectives of the course are to: 1) Update the audience on the curreultrasound imaging in space flight; 2) Discuss the unique aspects of conducting ultrasound imaging on ISS, interplanetary transit, ultrasound imaging on ISS, interplanetary transit, and lunar surface operations; and 3) Review preliminary data obtained in simulations of medical imaging in lunar surface operations.

  15. Bi-photon imaging and diagnostics using ultra-small diagnostic probes engineered from semiconductor nanocrystals and single-domain antibodies

    NASA Astrophysics Data System (ADS)

    Hafian, Hilal; Sukhanova, Alyona; Chames, Patrick; Baty, Daniel; Pluot, Michel; Cohen, Jacques H. M.; Nabiev, Igor R.; Millot, Jean-Marc

    2012-10-01

    Semiconductor fluorescent quantum dots (QDs) have just demonstrated their numerous advantages over organic dyes in bioimaging and diagnostics. One of characteristics of QDs is a very large cross section of their twophoton absorption. A common approach to biodetection by means of QDs is to use monoclonal antibodies (mAbs) for targeting. Recently, we have engineered ultrasmall diagnostic nanoprobes (sdAb-QD) based on highly oriented conjugates of QDs with the single-domain antibodies (sdAbs) against cancer biomarkers. With a molecular weight of only 13 kDa (12-fold smaller than full-size mAbs) and extreme stability and capacity to refolding, sdAbs are the smallest functional Ab fragments capable of binding antigens with affinities comparable to those of conventional Abs. Ultrasmall diagnostic sdAb-QD nanoprobes were engineered through oriented conjugation of QDs with sdAbs. This study is the first to demonstrate the possibility of immunohistochemical imaging of colon carcinoma biomarkers with sdAb-QD conjugates by means of two-photon excitation. The optimal excitation conditions for imaging of the markers in clinical samples with sdAb-QD nanoprobes have been determined. The absence of sample autofluorescence significantly improves the sensitivity of biomarker detection with the use of the two-photon excitation diagnostic setup.

  16. Microwave and digital imaging technology reduce turnaround times for diagnostic electron microscopy.

    PubMed

    Giberson, Richard T; Austin, Ronald L; Charlesworth, Jon; Adamson, Grete; Herrera, Guillermo A

    2003-01-01

    The contributions of microwave methods and digital imaging techniques, when taken together, can reduce routine specimen processing and evaluation for diagnostic electron microscopy to a time frame never thought possible. Significant improvements in both technologies over the last 5 years led the authors to evaluate their combined attributes as the most likely candidate to provide a realistic solution in the reduction of turnaround times for diagnostic electron microscopy. For diagnostic electron microscopy to compete favorably with immunohistochemistry and other ancillary diagnostic techniques, it must improve its turnaround time. To evaluate this hypothesis the microwave-assisted processing results of over 2,000 diagnostic cases were evaluated as was a digital image administration system used for the acquisition and dissemination of diagnostic results. The incorporation of both technologies resulted in turnaround times being reduced to 4 h or less.

  17. Diagnostic Imaging Integrated Network: A Teleradiology Pilot in Public Hospitals in Uruguay.

    PubMed

    Acosta, Lilian; Ruibal Faral, Karime

    2015-01-01

    A network of health care centers allows radiologists to share diagnostic images in different areas of Uruguay. This solution is based on an informatics multicenter application for center management, enabling the creation, storage and distribution of images and reports from different imaging modalities according to outsourcing agreements. The solution improves health care territorial equity and reduces asymmetry in resources distribution.

  18. Simple fractal method of assessment of histological images for application in medical diagnostics

    PubMed Central

    2010-01-01

    We propose new method of assessment of histological images for medical diagnostics. 2-D image is preprocessed to form 1-D landscapes or 1-D signature of the image contour and then their complexity is analyzed using Higuchi's fractal dimension method. The method may have broad medical application, from choosing implant materials to differentiation between benign masses and malignant breast tumors. PMID:21134258

  19. Advances in diagnostic imaging for pathologic conditions of the jaws.

    PubMed

    Benson, Byron W; Flint, Diane J; Liang, Hui; Opatowsky, Michael J

    2014-12-01

    Advances in dental and maxillofacial imaging are delineated along with the advantages and disadvantages of each imaging modality. The imaging modalities that are included are intraoral radiography, panoramic radiography, cone-beam computed tomography, multidetector computed tomography, magnetic resonance imaging, nuclear medicine, and ultrasound.

  20. Ancillary diagnostic imaging. Angiography, ultrasonography, scintigraphy, and xeroradiography

    SciTech Connect

    Pharr, J.W.

    1985-03-01

    Veterinary medical imaging is now accepted as including a number of imaging modalities other than conventional radiography. Although the wide availability and relatively low cost of conventional radiography will keep it in the forefront of veterinary medical imaging, other imaging modalities or techniques such as those discussed in this article will, where available, be of significant value in selected cases of bovine lameness.

  1. Global Auroral Imaging as a Remote Diagnostic of Geospace

    NASA Technical Reports Server (NTRS)

    Germany, G. A.; Richards, P. G.; Parks, G. K.; Brittnacher, M. J.; Spann, J. F., Jr.

    1997-01-01

    Images of the Earth's aurora, taken from space, can be used to examine plasma behavior throughout the magnetospheric regions surrounding the earth. The coupling of the magnetospheric plasmas through the ionosphere are discussed. A summary of past and current imaging technology is given and then specific examples of remote sensing are given using images from the Ultraviolet Imager aboard the POLAR satellite.

  2. Investigating the Link Between Radiologists Gaze, Diagnostic Decision, and Image Content

    SciTech Connect

    Tourassi, Georgia; Voisin, Sophie; Paquit, Vincent C; Krupinski, Elizabeth

    2013-01-01

    Objective: To investigate machine learning for linking image content, human perception, cognition, and error in the diagnostic interpretation of mammograms. Methods: Gaze data and diagnostic decisions were collected from six radiologists who reviewed 20 screening mammograms while wearing a head-mounted eye-tracker. Texture analysis was performed in mammographic regions that attracted radiologists attention and in all abnormal regions. Machine learning algorithms were investigated to develop predictive models that link: (i) image content with gaze, (ii) image content and gaze with cognition, and (iii) image content, gaze, and cognition with diagnostic error. Both group-based and individualized models were explored. Results: By pooling the data from all radiologists machine learning produced highly accurate predictive models linking image content, gaze, cognition, and error. Merging radiologists gaze metrics and cognitive opinions with computer-extracted image features identified 59% of the radiologists diagnostic errors while confirming 96.2% of their correct diagnoses. The radiologists individual errors could be adequately predicted by modeling the behavior of their peers. However, personalized tuning appears to be beneficial in many cases to capture more accurately individual behavior. Conclusions: Machine learning algorithms combining image features with radiologists gaze data and diagnostic decisions can be effectively developed to recognize cognitive and perceptual errors associated with the diagnostic interpretation of mammograms.

  3. Gold-manganese nanoparticles for targeted diagnostic and imaging

    SciTech Connect

    Murph, Simona Hunyadi

    2015-11-10

    Imagine the possibility of non-invasive, non-radiation based Magnetic resonance imaging (MRI) in combating cardiac disease. Researchers at the Savannah River National Laboratory (SRNL) are developing a process that would use nanotechnology in a novel, targeted approach that would allow MRIs to be more descriptive and brighter, and to target specific organs. Researchers at SRNL have discovered a way to use multifunctional metallic gold-manganese nanoparticles to create a unique, targeted positive contrast agent. SRNL Senior Scientist Dr. Simona Hunyadi Murph says she first thought of using the nanoparticles for cardiac disease applications after learning that people who survive an infarct exhibit up to 15 times higher rate of developing chronic heart failure, arrhythmias and/or sudden death compared to the general population. Without question, nanotechnology will revolutionize the future of technology. The development of functional nanomaterials with multi-detection modalities opens up new avenues for creating multi-purpose technologies for biomedical applications.

  4. Combination of fluorescence imaging and local spectrophotometry in fluorescence diagnostics of early cancer of larynx and bronchi

    SciTech Connect

    Sokolov, Vladimir V; Filonenko, E V; Telegina, L V; Boulgakova, N N; Smirnov, V V

    2002-11-30

    The results of comparative studies of autofluorescence and 5-ALA-induced fluorescence of protoporphyrin IX, used in the diagnostics of early cancer of larynx and bronchi, are presented. The autofluorescence and 5-ALA-induced fluorescence images of larynx and bronchial tissues are analysed during the endoscopic study. The method of local spectrophotometry is used to verify findings obtained from fluorescence images. It is shown that such a combined approach can be efficiently used to improve the diagnostics of precancer and early cancer, to detect a primary multiple tumours, as well as for the diagnostics of a residual tumour or an early recurrence after the endoscopic, surgery or X-ray treatment. The developed approach allows one to minimise the number of false-positive results and to reduce the number of biopsies, which are commonly used in the white-light bronchoscopy search for occult cancerous loci. (laser biology and medicine)

  5. Multiphoton microscopy as a diagnostic imaging modality for pancreatic neoplasms without hematoxylin and eosin stains

    NASA Astrophysics Data System (ADS)

    Chen, Youting; Chen, Jing; Chen, Hong; Hong, Zhipeng; Zhu, Xiaoqin; Zhuo, Shuangmu; Chen, Yanling; Chen, Jianxin

    2014-09-01

    Hematoxylin and eosin (H&E) staining of tissue samples is the standard approach in histopathology for imaging and diagnosing cancer. Recent reports have shown that multiphoton microscopy (MPM) provides better sample interface with single-cell resolution, which enhances traditional H&E staining and offers a powerful diagnostic tool with potential applications in oncology. The purpose of this study was to further expand the versatility of MPM by establishing the optical parameters required for imaging unstained histological sections of pancreatic neoplasms, thereby providing an efficient and environmentally sustainable alternative to H&E staining while improving the accuracy of pancreatic cancer diagnoses. We found that the high-resolution MPM images clearly distinguish between the structure of normal pancreatic tissues compared with pancreatic neoplasms in unstained histological sections, and discernable differences in tissue architecture and cell morphology between normal versus tumorigenic cells led to enhanced optical diagnosis of cancerous tissue. Moreover, quantitative assessment of the cytomorphological features visualized from MPM images showed significant differences in the nuclear-cytoplasmic ratios of pancreatic neoplasms compared with normal pancreas, as well as further distinguished pancreatic malignant tumors from benign tumors. These results indicate that the MPM could potentially serve as an optical tool for the diagnosis of pancreatic neoplasms in unstained histological sections.

  6. Multiphoton microscopy as a diagnostic imaging modality for pancreatic neoplasms without hematoxylin and eosin stains.

    PubMed

    Chen, Youting; Chen, Jing; Chen, Hong; Hong, Zhipeng; Zhu, Xiaoqin; Zhuo, Shuangmu; Chen, Yanling; Chen, Jianxin

    2014-09-01

    Hematoxylin and eosin (H&E) staining of tissue samples is the standard approach in histopathology for imaging and diagnosing cancer. Recent reports have shown that multiphoton microscopy (MPM) provides better sample interface with single-cell resolution, which enhances traditional H&E staining and offers a powerful diagnostic tool with potential applications in oncology. The purpose of this study was to further expand the versatility of MPM by establishing the optical parameters required for imaging unstained histological sections of pancreatic neoplasms, thereby providing an efficient and environmentally sustainable alternative to H&E staining while improving the accuracy of pancreatic cancer diagnoses. We found that the high-resolution MPM images clearly distinguish between the structure of normal pancreatic tissues compared with pancreatic neoplasms in unstained histological sections, and discernable differences in tissue architecture and cell morphology between normal versus tumorigenic cells led to enhanced optical diagnosis of cancerous tissue. Moreover, quantitative assessment of the cytomorphological features visualized from MPM images showed significant differences in the nuclear–cytoplasmic ratios of pancreatic neoplasms compared with normal pancreas, as well as further distinguished pancreatic malignant tumors from benign tumors. These results indicate that the MPM could potentially serve as an optical tool for the diagnosis of pancreatic neoplasms in unstained histological sections.

  7. Diagnostic performance of combined noninvasive coronary angiography and myocardial perfusion imaging using 320 row detector computed tomography: design and implementation of the CORE320 multicenter, multinational diagnostic study.

    PubMed

    Vavere, Andrea L; Simon, Gregory G; George, Richard T; Rochitte, Carlos E; Arai, Andrew E; Miller, Julie M; Di Carli, Marcello; Arbab-Zadeh, Armin; Zadeh, Armin A; Dewey, Marc; Niinuma, Hiroyuki; Laham, Roger; Rybicki, Frank J; Schuijf, Joanne D; Paul, Narinder; Hoe, John; Kuribyashi, Sachio; Sakuma, Hajime; Nomura, Cesar; Yaw, Tan Swee; Kofoed, Klaus F; Yoshioka, Kunihiro; Clouse, Melvin E; Brinker, Jeffrey; Cox, Christopher; Lima, Joao A C

    2011-01-01

    Multidetector coronary computed tomography angiography (CTA) is a promising modality for widespread clinical application because of its noninvasive nature and high diagnostic accuracy as found in previous studies using 64 to 320 simultaneous detector rows. It is, however, limited in its ability to detect myocardial ischemia. In this article, we describe the design of the CORE320 study ("Combined coronary atherosclerosis and myocardial perfusion evaluation using 320 detector row computed tomography"). This prospective, multicenter, multinational study is unique in that it is designed to assess the diagnostic performance of combined 320-row CTA and myocardial CT perfusion imaging (CTP) in comparison with the combination of invasive coronary angiography and single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). The trial is being performed at 16 medical centers located in 8 countries worldwide. CT has the potential to assess both anatomy and physiology in a single imaging session. The co-primary aim of the CORE320 study is to define the per-patient diagnostic accuracy of the combination of coronary CTA and myocardial CTP to detect physiologically significant coronary artery disease compared with (1) the combination of conventional coronary angiography and SPECT-MPI and (2) conventional coronary angiography alone. If successful, the technology could revolutionize the management of patients with symptomatic CAD.

  8. Improved image quality and diagnostic potential using ultra-high-resolution computed tomography of the lung with small scan FOV: A prospective study

    PubMed Central

    Wang, Yali; Hamal, Preeti; You, Xiaofang; Mao, Haixia; Li, Fei; Sun, Xiwen

    2017-01-01

    The aim of this study was to assess whether CT imaging using an ultra-high-resolution CT (UHRCT) scan with a small scan field of view (FOV) provides higher image quality and helps to reduce the follow-up period compared with a conventional high-resolution CT (CHRCT) scan. We identified patients with at least one pulmonary nodule at our hospital from July 2015 to November 2015. CHRCT and UHRCT scans were conducted in all enrolled patients. Three experienced radiologists evaluated the image quality using a 5-point score and made diagnoses. The paired images were displayed side by side in a random manner and annotations of scan information were removed. The following parameters including image quality, diagnostic confidence of radiologists, follow-up recommendations and diagnostic accuracy were assessed. A total of 52 patients (62 nodules) were included in this study. UHRCT scan provides a better image quality regarding the margin of nodules and solid internal component compared to that of CHRCT (P < 0.05). Readers have higher diagnostic confidence based on the UHRCT images than of CHRCT images (P<0.05). The follow-up recommendations were significantly different between UHRCT and CHRCT images (P<0.05). Compared with the surgical pathological findings, UHRCT had a relative higher diagnostic accuracy than CHRCT (P > 0.05). These findings suggest that the UHRCT prototype scanner provides a better image quality of subsolid nodules compared to CHRCT and contributes significantly to reduce the patients' follow-up period. PMID:28231320

  9. Computational Diagnostic Techniques for Electromagnetic Scattering: Analytical Imaging, Near Fields, and Surface Currents

    NASA Technical Reports Server (NTRS)

    Hom, Kam W.; Talcott, Noel A., Jr.; Shaeffer, John

    1997-01-01

    This paper presents three techniques and the graphics implementations which can be used as diagnostic aides in the design and understanding of scattering structures: Imaging, near fields, and surface current displays. The imaging analysis is a new bistatic k space approach which has potential for much greater information than standard experimental approaches. The near field and current analysis are implementations of standard theory while the diagnostic graphics displays are implementations exploiting recent computer engineering work station graphics libraries.

  10. Advanced diagnostic imaging and surgical treatment of an odontogenic retromasseteric abscess in a guinea pig.

    PubMed

    Capello, V; Lennox, A

    2015-02-01

    A two-year-old guinea pig presented for difficulty chewing. Examination and diagnostic imaging, including computed tomography and magnetic resonance, revealed an odontogenic retromasseteric abscess associated with a mandibular cheek tooth. Treatment included removal of the abscess and marsupialisation of the surgical site for repeated debridement and healing by second intention. Unique features of this case included the use of advanced diagnostic imaging and utilisation of marsupialisation for surgical correction.

  11. Image-matching as a medical diagnostic support tool (DST) for brain diseases in children.

    PubMed

    Huang, H K; Nielsen, J F; Nelson, Marvin D; Liu, Lifeng

    2005-01-01

    Imaging-matching is an important research area in imaging informatics. We have developed and evaluated a novel diagnostic support tool (DST) based on medical image matching using MR brain images. The approach consists of two steps, database generation and image matching. The database contains pre-diagnosed MR brain images. As the images are added to the database, they are registered to the 3D Talairach coordinate system. In addition, regions of interests (ROI) are generated, and image-processing techniques are used to extract relevant image parameters related to the brain and diseases from the ROIs and from the entire MR image. The second step is to retrieve relevant information from the database by performing image matching. In this step, the physician first submits a query image. The DST computes the similarity between the query image and each of the images in the database, and then presents the most similar images to the user. Since the database contains pre-diagnosed images, the retrieved cases tend to contain relevant diagnostic information. To evaluate the usefulness of the DST in a clinical setting, pediatric brain diseases were used. The database contains 2500 pediatric patients between ages 0 and 18 with brain Magnetic Resonance (MR) images of known brain lesions. A testbed was established at the Children's Hospital Los Angeles (CHLA) for acquiring MR images from the PACS server of patients with known lesions. These images were matched against those in the DST pediatric brain MR database. An expert pediatric neuroradiologist evaluated the matched results. We found that in most cases, the image-matching method was able to quickly retrieve images with relevant diagnostic content. The evaluation method and results are given.

  12. Diagnostic Imaging of the Lower Respiratory Tract in Neonatal Foals: Radiography and Computed Tomography.

    PubMed

    Lascola, Kara M; Joslyn, Stephen

    2015-12-01

    Diagnostic imaging plays an essential role in the diagnosis and monitoring of lower respiratory disease in neonatal foals. Radiography is most widely available to equine practitioners and is the primary modality that has been used for the characterization of respiratory disease in foals. Computed tomography imaging, although still limited in availability to the general practitioner, offers advantages over radiography and has been used diagnostically in neonatal foals with respiratory disease. Recognition of appropriate imaging protocols and patient-associated artifacts is critical for accurate image interpretation regardless of the modality used. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Dual Gated Imaging system for Enhanced Fluorescent Diagnostics Measurements

    DTIC Science & Technology

    1992-03-13

    Imaging: An Approach for Fuel Equivalence Ratio Imaging", Applied Spectroscopy , 45, 938 (1991). 2. R.M. Ballew and J.N. Demas, "An Error Analysis of...and S.C. Yang, Applied Spectroscopy , 39, 266 (1985). of Figures Block diagram of dual gated imaging system VII. List Figure 1 Figure 2

  14. #7 Comparing STEREO, Simulated Helioseismic Images

    NASA Image and Video Library

    Farside direct observations from STEREO (left) and simultaneous helioseismic reconstructions (right). Medium to large size active regions clearly appear on the helioseismic images, however the smal...

  15. Clinical outcomes and cost effectiveness of accelerated diagnostic protocol in a chest pain center compared with routine care of patients with chest pain.

    PubMed

    Asher, Elad; Reuveni, Haim; Shlomo, Nir; Gerber, Yariv; Beigel, Roy; Narodetski, Michael; Eldar, Michael; Or, Jacob; Hod, Hanoch; Shamiss, Arie; Matetzky, Shlomi

    2015-01-01

    The aim of this study was to compare in patients presenting with acute chest pain the clinical outcomes and cost-effectiveness of an accelerated diagnostic protocol utilizing contemporary technology in a chest pain unit versus routine care in an internal medicine department. Hospital and 90-day course were prospectively studied in 585 consecutive low-moderate risk acute chest pain patients, of whom 304 were investigated in a designated chest pain center using a pre-specified accelerated diagnostic protocol, while 281 underwent routine care in an internal medicine ward. Hospitalization was longer in the routine care compared with the accelerated diagnostic protocol group (p<0.001). During hospitalization, 298 accelerated diagnostic protocol patients (98%) vs. 57 (20%) routine care patients underwent non-invasive testing, (p<0.001). Throughout the 90-day follow-up, diagnostic imaging testing was performed in 125 (44%) and 26 (9%) patients in the routine care and accelerated diagnostic protocol patients, respectively (p<0.001). Ultimately, most patients in both groups had non-invasive imaging testing. Accelerated diagnostic protocol patients compared with those receiving routine care was associated with a lower incidence of readmissions for chest pain [8 (3%) vs. 24 (9%), p<0.01], and acute coronary syndromes [1 (0.3%) vs. 9 (3.2%), p<0.01], during the follow-up period. The accelerated diagnostic protocol remained a predictor of lower acute coronary syndromes and readmissions after propensity score analysis [OR = 0.28 (CI 95% 0.14-0.59)]. Cost per patient was similar in both groups [($2510 vs. $2703 for the accelerated diagnostic protocol and routine care group, respectively, (p = 0.9)]. An accelerated diagnostic protocol is clinically superior and as cost effective as routine in acute chest pain patients, and may save time and resources.

  16. Use of an Online Education Platform to Enhance Patients' Knowledge About Radiation in Diagnostic Imaging.

    PubMed

    Steele, Joseph R; Jones, A Kyle; Clarke, Ryan K; Shiao, Sue J; Wei, Wei; Shoemaker, Stowe; Parmar, Simrit

    2017-03-01

    The aim of this study was to compare the impact of a digital interactive education platform and standard paper-based education on patients' knowledge regarding ionizing radiation. Beginning in January 2015, patients at a tertiary cancer center scheduled for diagnostic imaging procedures were randomized to receive information about ionizing radiation delivered through a web-based interactive education platform (interactive education group), the same information in document format (document education group), or no specialized education (control group). Patients who completed at least some education and control group patients were invited to complete a knowledge assessment; interactive education patients were invited to provide feedback about satisfaction with their experience. A total of 2,226 patients participated. Surveys were completed by 302 of 745 patients (40.5%) participating in interactive education, 488 of 993 (49.1%) participating in document education, and 363 of 488 (74.4%) in the control group. Patients in the interactive education group were significantly more likely to say that they knew the definition of ionizing radiation, outperformed the other groups in identifying which imaging examinations used ionizing radiation, were significantly more likely to identify from a list which imaging modality had the highest radiation dose, and tended to perform better when asked about the tissue effects of radiation in diagnostic imaging, although this difference was not significant. In the interactive education group, 84% of patients were satisfied with the experience, and 79% said that they would recommend the program. Complex information on a highly technical subject with personal implications for patients may be conveyed more effectively using electronic platforms, and this approach is well accepted. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  17. Comparative Capabilities of Clinical Assessment, Diagnostic Criteria, and Polysomnography in Detecting Sleep Bruxism

    PubMed Central

    Palinkas, Marcelo; De Luca Canto, Graziela; Rodrigues, Laíse Angélica Mendes; Bataglion, César; Siéssere, Selma; Semprini, Marisa; Regalo, Simone Cecilio Hallak

    2015-01-01

    Objective: To evaluate the diagnostic capability of signs and symptoms of sleep bruxism (SB) as per the American Academy of Sleep Medicine (AASM) criteria and a diagnostic grading system proposed by international experts for assessing SB. Methods: The study was conducted in three phases (interview, physical examination, and sleep studies). Subjects were asked about self-reported tooth grinding sounds occurring during sleep, muscle fatigue, temporal headaches, jaw muscle pain, and jaw locking. A visual examination was conducted to check for presence of abnormal tooth wear. A full-night polysomnography (PSG) was performed. After three phases, the subjects were divided into two groups matched by age and gender: Case Group, 45 SB subjects, and Control Group, 45 non-SB subjects. Diagnostic accuracy measurements were calculated for each sign or symptom individually and for the two diagnostic criteria analyzed. Results: Muscle fatigue, temporal headaches, and AASM criteria were associated with highest sensitivity (78%, 67%, 58%, respectively) and also with highest diagnostic odds ratio (OR = 9.63, 9.25, 6.33, respectively). Jaw locking, muscle pain, and the criterion of “probable SB” were associated with the worst sensitivity (16%, 18%, 22%, respectively). Conclusions: Presence of muscle fatigue and temporal headaches can be considered good tools to screen SB patients. None of the diagnostic criteria evaluated was able to accurately identify patients with SB. AASM criteria had the strongest diagnostic capabilities and—although they do not attain diagnostic values high enough to replace the current gold standard (PSG)—should be used as a screening tool to identify SB. Citation: Palinkas M, De Luca Canto G, Rodrigues LA, Bataglion C, Siéssere S, Semprini M, Regalo SC. Comparative capabilities of clinical assessment, diagnostic criteria, and polysomnography in detecting sleep bruxism. J Clin Sleep Med 2015;11(11):1319–1325. PMID:26235152

  18. Gender incongruence: a comparative study using ICD-10 and DSM-5 diagnostic criteria.

    PubMed

    Soll, Bianca M; Robles-García, Rebeca; Brandelli-Costa, Angelo; Mori, Daniel; Mueller, Andressa; Vaitses-Fontanari, Anna M; Cardoso-da-Silva, Dhiordan; Schwarz, Karine; Abel-Schneider, Maiko; Saadeh, Alexandre; Lobato, Maria-Inês-Rodrigues

    2017-10-02

    To compare the presence of criteria listed in the DSM-5 and ICD-10 diagnostic manuals in a Brazilian sample of transgender persons seeking health services specifically for physical transition. This multicenter cross-sectional study included a sample of 103 subjects who sought services for gender identity disorder in two main reference centers in Brazil. The method involved a structured interview encompassing the diagnostic criteria in the two manuals. The results revealed that despite theoretical disagreement about the criteria, the manuals overlap regarding diagnosis confirmation; the DSM-5 was more inclusive (97.1%) than the ICD-10 (93.2%) in this population. Although there is no consensus on diagnostic criteria on transgenderism in the diversity of social and cultural contexts, more comprehensive diagnostic criteria are evolving due to society's increasing inclusivity.

  19. Acoustic radiation force elasticity imaging in diagnostic ultrasound.

    PubMed

    Doherty, Joshua R; Trahey, Gregg E; Nightingale, Kathryn R; Palmeri, Mark L

    2013-04-01

    The development of ultrasound-based elasticity imaging methods has been the focus of intense research activity since the mid-1990s. In characterizing the mechanical properties of soft tissues, these techniques image an entirely new subset of tissue properties that cannot be derived with conventional ultrasound techniques. Clinically, tissue elasticity is known to be associated with pathological condition and with the ability to image these features in vivo; elasticity imaging methods may prove to be invaluable tools for the diagnosis and/or monitoring of disease. This review focuses on ultrasound-based elasticity imaging methods that generate an acoustic radiation force to induce tissue displacements. These methods can be performed noninvasively during routine exams to provide either qualitative or quantitative metrics of tissue elasticity. A brief overview of soft tissue mechanics relevant to elasticity imaging is provided, including a derivation of acoustic radiation force, and an overview of the various acoustic radiation force elasticity imaging methods.

  20. Acoustic Radiation Force Elasticity Imaging in Diagnostic Ultrasound

    PubMed Central

    Doherty, Joshua R.; Trahey, Gregg E.; Nightingale, Kathryn R.; Palmeri, Mark L.

    2013-01-01

    The development of ultrasound-based elasticity imaging methods has been the focus of intense research activity since the mid-1990s. In characterizing the mechanical properties of soft tissues, these techniques image an entirely new subset of tissue properties that cannot be derived with conventional ultrasound techniques. Clinically, tissue elasticity is known to be associated with pathological condition and with the ability to image these features in vivo, elasticity imaging methods may prove to be invaluable tools for the diagnosis and/or monitoring of disease. This review focuses on ultrasound-based elasticity imaging methods that generate an acoustic radiation force to induce tissue displacements. These methods can be performed non-invasively during routine exams to provide either qualitative or quantitative metrics of tissue elasticity. A brief overview of soft tissue mechanics relevant to elasticity imaging is provided, including a derivation of acoustic radiation force, and an overview of the various acoustic radiation force elasticity imaging methods. PMID:23549529

  1. Diagnostic emergency imaging utilization at an academic trauma center from 1996 to 2012.

    PubMed

    Arasu, Vignesh A; Abujudeh, Hani H; Biddinger, Paul D; Noble, Vicki E; Halpern, Elkan F; Thrall, James H; Novelline, Robert A

    2015-05-01

    The aim of this study was to retrospectively review the growth rate in emergency radiology volume at an urban academic trauma center from 1996 to 2012. The authors reviewed aggregated billing data, for which the requirement for institutional review board approval was waived, from 1,458,230 diagnostic radiologic examinations ordered for emergency department (ED) visits from 1996 to 2012. The growth rate was calculated as the average annual percentage change in imaging examinations per ED visits. The growth rates between 1996 to 2003 and 2004 to 2012 were statistically compared using a t test. ED patient visits showed continual growth at an average of 3% per year. Total imaging per ED visit grew from 1996 to 2003 at 4 ± 4% per year but significantly decreased from 2004 to 2012 at -2 ± 3% per year (P = .01). By modality, statistically significant decreased growth was observed in CT and MRI from 2004 to 2012. Ultrasound and x-ray showed unchanged growth from 1996 through 2012. ED physician ultrasound data available for 2002 to 2011 also showed increased growth. When adjusting ED imaging volume by ED visits, significantly decreased growth of overall ED imaging, specifically CT and MRI, was observed during the past 9 years. This may be due to slowing of new imaging indications, improved awareness of practice guidelines, and increased use of ultrasound. Although the national health care discussion focuses on continual imaging growth, these results demonstrate that long-term stability in ED imaging utilization is achievable. Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  2. Diagnostic Emergency Imaging Utilization at an Academic Trauma Center From 1996 to 2012

    PubMed Central

    Arasu, Vignesh A.; Abujudeh, Hani H.; Biddinger, Paul D.; Noble, Vicki E.; Halpern, Elkan F.; Thrall, James H.; Novelline, Robert A.

    2015-01-01

    Purpose The aim of this study was to retrospectively review the growth rate in emergency radiology volume at an urban academic trauma center from 1996 to 2012. Methods The authors reviewed aggregated billing data, for which the requirement for institutional review board approval was waived, from 1,458,230 diagnostic radiologic examinations ordered for emergency department (ED) visits from 1996 to 2012. The growth rate was calculated as the average annual percentage change in imaging examinations per ED visits. The growth rates between 1996 to 2003 and 2004 to 2012 were statistically compared using a t test. Results ED patient visits showed continual growth at an average of 3% per year. Total imaging per ED visit grew from 1996 to 2003 at 4 ± 4% per year but significantly decreased from 2004 to 2012 at −2 ± 3% per year (P = .01). By modality, statistically significant decreased growth was observed in CT and MRI from 2004 to 2012. Ultrasound and x-ray showed unchanged growth from 1996 through 2012. ED physician ultrasound data available for 2002 to 2011 also showed increased growth. Conclusions When adjusting ED imaging volume by ED visits, significantly decreased growth of overall ED imaging, specifically CT and MRI, was observed during the past 9 years. This may be due to slowing of new imaging indications, improved awareness of practice guidelines, and increased use of ultrasound. Although the national health care discussion focuses on continual imaging growth, these results demonstrate that long-term stability in ED imaging utilization is achievable. PMID:25622765

  3. WE-AB-206-01: Diagnostic Ultrasound Imaging Quality Assurance.

    PubMed

    Zagzebski, J

    2016-06-01

    The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging.

  4. Image quality assessment in panoramic dental radiography: a comparative study between conventional and digital systems.

    PubMed

    Sabarudin, Akmal; Tiau, Yu Jin

    2013-02-01

    This study is designed to compare and evaluate the diagnostic image quality of dental panoramic radiography between conventional and digital systems. Fifty-four panoramic images were collected and divided into three groups consisting of conventional, digital with and without post processing image. Each image was printed out and scored subjectively by two experienced dentists who were blinded to the exposure parameters and system protocols. The evaluation covers of anatomical coverage and structures, density and image contrast. The overall image quality score revealed that digital panoramic with post-processing scored the highest of 3.45±0.19, followed by digital panoramic system without post-processing and conventional panoramic system with corresponding scores of 3.33±0.33 and 2.06±0.40. In conclusion, images produced by digital panoramic system are better in diagnostic image quality than that from conventional panoramic system. Digital post-processing visualization can improve diagnostic quality significantly in terms of radiographic density and contrast.

  5. Image quality assessment in panoramic dental radiography: a comparative study between conventional and digital systems

    PubMed Central

    Tiau, Yu Jin

    2013-01-01

    This study is designed to compare and evaluate the diagnostic image quality of dental panoramic radiography between conventional and digital systems. Fifty-four panoramic images were collected and divided into three groups consisting of conventional, digital with and without post processing image. Each image was printed out and scored subjectively by two experienced dentists who were blinded to the exposure parameters and system protocols. The evaluation covers of anatomical coverage and structures, density and image contrast. The overall image quality score revealed that digital panoramic with post-processing scored the highest of 3.45±0.19, followed by digital panoramic system without post-processing and conventional panoramic system with corresponding scores of 3.33±0.33 and 2.06±0.40. In conclusion, images produced by digital panoramic system are better in diagnostic image quality than that from conventional panoramic system. Digital post-processing visualization can improve diagnostic quality significantly in terms of radiographic density and contrast. PMID:23483085

  6. Definitions and outlook targeting x-ray exposure of patients in diagnostic imaging

    NASA Astrophysics Data System (ADS)

    Regulla, Dieter F.

    2011-03-01

    Computer tomography (CT) is vital and currently irreplaceable in diagnostic radiology. But CT operates with ionizing radiation which may cause cancer or non-cancer diseases in humans. The degree of radiation impact depends on the dose administered by an investigation. And this is the core issue: Even CT exams executed lege artis, administer doses to patients which by magnitude are far beyond the level of hitherto known doses of conventional film-screen techniques. Patients undergoing one or multiple CT examinations, digital angiographies or interventions will be exposed to effective doses between roughly several mSv and several 100 mSv depending on type and frequency of the diagnostic investigations. From the radiation protection point of view, there is therefore the worldwide problem of formulating firm rules for the control of these high-dose investigations, as dose limits can not be established for reasons of the medical benefit. This makes the difference compared with radiation protection for occupationally exposed persons. What remains is "software", namely "justification" and "optimization". Justification requires balancing the interests between the health benefit and the potential harm of an exam which has to be responsibly executed by the physician himself; therefore the radiologists' associations are in the duty to prepare practicable rules for justification. Optimization again needs a cooperative solution, and that is the establishment of reference doses for diagnostic examinations, to be checked by the technical service of the producers' companies. Experts and authorities have been aware of the high-dose dilemma in diagnostic imaging since long. It is time for the reflection of active solutions and their implementation into practice.

  7. Feasibility and Diagnostic Value of Cardiovascular Magnetic Resonance Imaging After Acute Ischemic Stroke of Undetermined Origin.

    PubMed

    Haeusler, Karl Georg; Wollboldt, Christian; Bentheim, Laura Zu; Herm, Juliane; Jäger, Sebastian; Kunze, Claudia; Eberle, Holger-Carsten; Deluigi, Claudia Christina; Bruder, Oliver; Malsch, Carolin; Heuschmann, Peter U; Endres, Matthias; Audebert, Heinrich J; Morguet, Andreas J; Jensen, Christoph; Fiebach, Jochen B

    2017-05-01

    Etiology of acute ischemic stroke remains undetermined (cryptogenic) in about 25% of patients after state-of-the-art diagnostic work-up. One-hundred and three patients with magnetic resonance imaging (MRI)-proven acute ischemic stroke of undetermined origin were prospectively enrolled and underwent 3-T cardiac MRI and magnetic resonance angiography of the aortic arch in addition to state-of-the-art diagnostic work-up, including transesophageal echocardiography (TEE). We analyzed the feasibility, diagnostic accuracy, and added value of cardiovascular MRI (cvMRI) compared with TEE for detecting sources of stroke. Overall, 102 (99.0%) ischemic stroke patients (median 63 years [interquartile range, 53-72], 24% female, median NIHSS (National Institutes of Health Stroke Scale) score on admission 2 [interquartile range, 1-4]) underwent cvMRI and TEE in hospital; 89 (86.4%) patients completed the cvMRI examination. In 93 cryptogenic stroke patients, a high-risk embolic source was found in 9 (8.7%) patients by cvMRI and in 11 (11.8%) patients by echocardiography, respectively. cvMRI and echocardiography findings were consistent in 80 (86.0%) patients, resulting in a degree of agreement of κ=0.24. In 82 patients with cryptogenic stroke according to routine work-up, including TEE, cvMRI identified stroke etiology in additional 5 (6.1%) patients. Late gadolinium enhancement consistent with previous myocardial infarction was found in 13 (14.6%) out of 89 stroke patients completing cvMRI. Only 2 of these 13 patients had known coronary artery disease. Our study demonstrated that cvMRI was feasible in the vast majority of included patients with acute ischemic stroke. The diagnostic information of cvMRI seems to be complementary to TEE but is not replacing echocardiography after acute ischemic stroke. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01917955. © 2017 American Heart Association, Inc.

  8. Bridging the Semantic Gap Between Diagnostic Histopathology and Image Analysis.

    PubMed

    Traore, Lamine; Kergosien, Yannick; Racoceanu, Daniel

    2017-01-01

    With the wider acceptance of Whole Slide Images (WSI) in histopathology domain, automatic image analysis algorithms represent a very promising solution to support pathologist's laborious tasks during the diagnosis process, to create a quantification-based second opinion and to enhance inter-observer agreement. In this context, reference vocabularies and formalization of the associated knowledge are especially needed to annotate histopathology images with labels complying with semantic standards. In this work, we elaborate a sustainable triptych able to bridge the gap between pathologists and image analysis scientists. The proposed paradigm is structured along three components: i) extracting a relevant semantic repository from the College of American Pathologists (CAP) organ-specific Cancer Checklists and associated Protocols (CC&P); ii) identifying imaging formalized knowledge issued from effective histopathology imaging methods highlighted by recent Digital Pathology (DP) contests and iii) proposing a formal representation of the imaging concepts and functionalities issued from major biomedical imaging software (MATLAB, ITK, ImageJ). Since the first step i) has been the object of a recent publication of our team, this study focuses on the steps ii) and iii). Our hypothesis is that the management of available semantic resources concerning the histopathology imaging tasks associated with effective methods highlighted by the recent DP challenges will facilitate the integration of WSI in clinical routine and support new generation of DP protocols.

  9. Histological Image Feature Mining Reveals Emergent Diagnostic Properties for Renal Cancer

    PubMed Central

    Kothari, Sonal; Phan, John H.; Young, Andrew N.; Wang, May D.

    2016-01-01

    Computer-aided histological image classification systems are important for making objective and timely cancer diagnostic decisions. These systems use combinations of image features that quantify a variety of image properties. Because researchers tend to validate their diagnostic systems on specific cancer endpoints, it is difficult to predict which image features will perform well given a new cancer endpoint. In this paper, we define a comprehensive set of common image features (consisting of 12 distinct feature subsets) that quantify a variety of image properties. We use a data-mining approach to determine which feature subsets and image properties emerge as part of an “optimal” diagnostic model when applied to specific cancer endpoints. Our goal is to assess the performance of such comprehensive image feature sets for application to a wide variety of diagnostic problems. We perform this study on 12 endpoints including 6 renal tumor subtype endpoints and 6 renal cancer grade endpoints. Keywords-histology, image mining, computer-aided diagnosis PMID:28163980

  10. Diagnostic and quality-assurance tools for low-contrast images obtained from array detectors

    NASA Technical Reports Server (NTRS)

    Hatfield, D. B.; Sandel, Bill R.

    1993-01-01

    We investigate methods of estimating a background image frame for subtraction from a data frame for use when a more suitable measured background frame is not available. We define background as any signal component that is not attributable to the phenomenon currently under investigation. We describe a technique that is based on pixel-by-pixel least-squares regression of images for computing a background frame from available data. We argue that the same technique can be a useful quality-assurance tool for evaluating instrument performance. For example, it can help to separate image structure resulting from the reading process from structure resulting from the characteristics of the detector itself. We demonstrate that background estimation can be nontrivial by comparing the results of different background estimation procedures by using data obtained from a CCD array detector. We investigate the temperature-dependent contributions of the detector and readout electronics to the total signal as a demonstration of the diagnostic capabilities of least-squares image regression.

  11. Diagnostic and quality-assurance tools for low-contrast images obtained from array detectors

    NASA Technical Reports Server (NTRS)

    Hatfield, D. B.; Sandel, Bill R.

    1993-01-01

    We investigate methods of estimating a background image frame for subtraction from a data frame for use when a more suitable measured background frame is not available. We define background as any signal component that is not attributable to the phenomenon currently under investigation. We describe a technique that is based on pixel-by-pixel least-squares regression of images for computing a background frame from available data. We argue that the same technique can be a useful quality-assurance tool for evaluating instrument performance. For example, it can help to separate image structure resulting from the reading process from structure resulting from the characteristics of the detector itself. We demonstrate that background estimation can be nontrivial by comparing the results of different background estimation procedures by using data obtained from a CCD array detector. We investigate the temperature-dependent contributions of the detector and readout electronics to the total signal as a demonstration of the diagnostic capabilities of least-squares image regression.

  12. Invited Review Article: Gas puff imaging diagnostics of edge plasma turbulence in magnetic fusion devices

    DOE PAGES

    Zweben, S. J.; Terry, J. L.; Stotler, D. P.; ...

    2017-04-27

    Gas puff imaging (GPI) is a diagnostic of plasma turbulence which uses a puff of neutral gas at the plasma edge to increase the local visible light emission for improved space-time resolution of plasma fluctuations. This paper reviews gas puff imaging diagnostics of edge plasma turbulence in magnetic fusion research, with a focus on the instrumentation, diagnostic cross-checks, and interpretation issues. The gas puff imaging hardware, optics, and detectors are described for about 10 GPI systems implemented over the past similar to 15 years. Comparison of GPI results with other edge turbulence diagnostic results is described, and many common featuresmore » are observed. Here, several issues in the interpretation of GPI measurements are discussed, and potential improvements in hardware and modeling are suggested.« less

  13. Financial impact of adopting implantable loop recorder diagnostic for unexplained syncope compared with conventional diagnostic pathway in Portugal.

    PubMed

    Providência, Rui; Candeias, Rui; Morais, Carlos; Reis, Hipólito; Elvas, Luís; Sanfins, Vitor; Farinha, Sara; Eggington, Simon; Tsintzos, Stelios

    2014-05-06

    To estimate the short- and long-term financial impact of early referral for implantable loop recorder diagnostic (ILR) versus conventional diagnostic pathway (CDP) in the management of unexplained syncope (US) in the Portuguese National Health Service (PNHS). A Markov model was developed to estimate the expected number of hospital admissions due to US and its respective financial impact in patients implanted with ILR versus CDP. The average cost of a syncope episode admission was estimated based on Portuguese cost data and landmark papers. The financial impact of ILR adoption was estimated for a total of 197 patients with US, based on the number of syncope admissions per year in the PNHS. Sensitivity analysis was performed to take into account the effect of uncertainty in the input parameters (hazard ratio of death; number of syncope events per year; probabilities and unit costs of each diagnostic test; probability of trauma and yield of diagnosis) over three-year and lifetime horizons. The average cost of a syncope event was estimated to be between 1,760€ and 2,800€. Over a lifetime horizon, the total discounted costs of hospital admissions and syncope diagnosis for the entire cohort were 23% lower amongst patients in the ILR group compared with the CDP group (1,204,621€ for ILR, versus 1,571,332€ for CDP). The utilization of ILR leads to an earlier diagnosis and lower number of syncope hospital admissions and investigations, thus allowing significant cost offsets in the Portuguese setting. The result is robust to changes in the input parameter values, and cost savings become more pronounced over time.

  14. Diagnostic sensitivity of radiography, ultrasonography, and magnetic resonance imaging for detecting shoulder osteochondrosis/osteochondritis dissecans in dogs.

    PubMed

    Wall, Corey R; Cook, Cristi R; Cook, James L

    2015-01-01

    Radiography, magnetic resonance imaging (MRI), and ultrasonography are commonly used for diagnosis of shoulder osteochondrosis and osteochondritis dissecans (OC/OCD) in dogs, however there is a lack of published information on the relative diagnostic sensitivities of these modalities. The purpose of this prospective study was to compare diagnostic sensitivities of these modalities for detecting shoulder OC/OCD in a group of dogs, using arthroscopy as the reference standard. Inclusion criteria were history and clinical findings consistent with osteochondrosis and/or osteochondritis dissecans involving at least one shoulder. With informed client consent, both shoulders for all included dogs were examined using standardized radiography, ultrasonography, MRI, and arthroscopy protocols. One of three veterinary surgeons recorded clinical and arthroscopic findings without knowledge of diagnostic imaging findings. One of two veterinary radiologists recorded diagnostic imaging findings without knowledge of clinical and arthroscopic findings. Eighteen client-owned dogs (n = 36 shoulders) met inclusion criteria. Diagnostic sensitivity, specificity, and accuracy (correct classification rate) values for detecting presence or absence of shoulder osteochondrosis/osteochondritis dissecans were as follows: radiography (88.5%, 90%, 88.9%), ultrasonography (92%, 60%, 82.6%), and MRI (96%, 88.9%, 94.4%). Odds of a correct diagnosis for MRI were 3.2 times more than ultrasonography and two times more than radiography. For MRI detection of lesions, the sagittal T2 or PD-FAT SAT sequences were considered to be most helpful. For radiographic detection of lesions, the additional supinated-mediolateral and pronated-mediolateral projections were considered to be most helpful. Findings from the current study support more evidence-based diagnostic imaging recommendations for dogs with clinically suspected shoulder osteochondrosis or osteochondritis dissecans. © 2014 American College of

  15. Contemporary Diagnostic Imaging Modalities for the Staging and Surveillance of Melanoma Patients: a Meta-analysis

    PubMed Central

    Xing, Yan; Bronstein, Yulia; Ross, Merrick I.; Askew, Robert L.; Lee, Jeffrey E.; Gershenwald, Jeffrey E.; Royal, Richard

    2011-01-01

    Background Meta-analyses were performed to examine the utility of ultrasonography, computed tomography (CT), positron emission tomography (PET), and a combination of both (PET-CT) for the staging and surveillance of melanoma patients. Method Patient-level data from 74 studies containing 10 528 patients (between January 1, 1990, and June, 30, 2009) were used to derive characteristics of the diagnostic tests used. Meta-analyses were conducted by use of Bayesian bivariate binomial models to estimate sensitivity and specificity. Diagnostic odds ratios [ie, true-positive results/false-negative results)/(false-positive results/true-negative results)] and their 95% credible intervals (CrIs) and positive predictive values were used as indicators of test performance. Results Among the four imaging methods examined for the staging of regional lymph nodes, ultrasonography had the highest sensitivity (60%, 95% CrI = 33% to 83%), specificity (97%, 95% CrI = 88% to 99%), and diagnostic odds ratio (42, 95% CrI = 8.08 to 249.8). For staging of distant metastases, PET-CT had the highest sensitivity (80%, 95% CrI = 53% to 93%), specificity (87%, 95% CrI = 54% to 97%), and diagnostic odds ratio (25, 95% CrI = 3.58 to 198.7). Similar trends were observed for melanoma surveillance of lymph node involvement, with ultrasonography having the highest sensitivity (96%, 95% CrI = 85% to 99%), specificity (99%, 95% CrI = 95% to 100%), and diagnostic odds ratio (1675, 95% CrI = 226.6 to 15,920). For distant metastases, PET-CT had the highest sensitivity (86%, 95% CrI = 76% to 93%), specificity (91%, 95% CrI = 79% to 97%), and diagnostic odds ratio (67, 95% CrI = 20.42 to 229.7). Positive predictive values were likewise highest for ultrasonography in lymph node staging and for PET-CT in detecting distant metastases. Conclusion Among the compared modalities, ultrasonography was superior for detecting lymph node metastases, and PET-CT was superior for the detection of distant metastases in both

  16. Diagnostic performance of a telemedicine system for ophthalmology: advantages in accuracy and speed compared to standard care.

    PubMed

    Chiang, Michael F; Wang, Lu; Kim, David; Scott, Karen; Richter, Grace; Kane, Steven; Flynn, John; Starren, Justin

    2010-11-13

    Telemedicine has potential to improve quality and delivery of medical care, particularly in image-oriented specialties where decisions are based on appearance of morphological features during examination. In the ophthalmology domain, nearly all published telemedicine studies have measured accuracy against a gold standard of ophthalmoscopic examination. The purposes of this study are to examine difficulties in defining an absolute gold standard and to compare diagnostic speed in a representative disease, retinopathy of prematurity. We compare results from ophthalmoscopic and telemedicine examinations by the same physicians. In 180 (86.5%) of 208 eyes, the two examinations produced the same diagnosis. In some discrepancies, there was rationale suggesting that telemedicine may have provided a more accurate diagnosis than ophthalmoscopic examination. The quantity and nature of these disagreements has important implications for evaluation of telemedicine systems in image-based specialties, and for the definition of gold standards in future studies.

  17. A Fast Visible Camera Divertor-Imaging Diagnostic on DIII-D

    SciTech Connect

    Roquemore, A; Maingi, R; Lasnier, C; Nishino, N; Evans, T; Fenstermacher, M; Nagy, A

    2007-06-19

    In recent campaigns, the Photron Ultima SE fast framing camera has proven to be a powerful diagnostic when applied to imaging divertor phenomena on the National Spherical Torus Experiment (NSTX). Active areas of NSTX divertor research addressed with the fast camera include identification of types of EDGE Localized Modes (ELMs)[1], dust migration, impurity behavior and a number of phenomena related to turbulence. To compare such edge and divertor phenomena in low and high aspect ratio plasmas, a multi-institutional collaboration was developed for fast visible imaging on NSTX and DIII-D. More specifically, the collaboration was proposed to compare the NSTX small type V ELM regime [2] and the residual ELMs observed during Type I ELM suppression with external magnetic perturbations on DIII-D[3]. As part of the collaboration effort, the Photron camera was installed recently on DIII-D with a tangential view similar to the view implemented on NSTX, enabling a direct comparison between the two machines. The rapid implementation was facilitated by utilization of the existing optics that coupled the visible spectral output from the divertor vacuum ultraviolet UVTV system, which has a view similar to the view developed for the divertor tangential TV camera [4]. A remote controlled filter wheel was implemented, as was the radiation shield required for the DIII-D installation. The installation and initial operation of the camera are described in this paper, and the first images from the DIII-D divertor are presented.

  18. The use of diagnostic imaging in sports medicine.

    PubMed

    Orchard, John W; Read, John W; Anderson, Ian Jock F

    2005-11-07

    Imaging should only be undertaken if it is likely to influence patient management. The dose of ionising radiation to the patient should be considered. Requesting the appropriate imaging method requires an understanding of the pathological process. Plain x-ray should still generally be the first imaging technique; exceptions include some forms of superficial tendinopathy, in which ultrasound may be more appropriate, and situations where radiation exposure is contraindicated, such as in a pregnant patient. The cost of the examination to the patient and the community should also be considered (eg, ultrasound v magnetic resonance imaging).

  19. Signal and noise transfer properties of photoelectric interactions in diagnostic x-ray imaging detectors.

    PubMed

    Hajdok, G; Yao, J; Battista, J J; Cunningham, I A

    2006-10-01

    Image quality in diagnostic x-ray imaging is ultimately limited by the statistical properties governing how, and where, x-ray energy is deposited in a detector. This in turn depends on the physics of the underlying x-ray interactions. In the diagnostic energy range (10-100 keV), most of the energy deposited in a detector is through photoelectric interactions. We present a theoretical model of the photoelectric effect that specifically addresses the statistical nature of energy absorption by photoelectrons, K and L characteristic x rays, and Auger electrons. A cascaded-systems approach is used that employs a complex structure of parallel cascades to describe signal and noise transfer through the photoelectric effect in terms of the modulation transfer function, Wiener noise power spectrum, and detective quantum efficiency (DQE). The model was evaluated by comparing results with Monte Carlo calculations for x-ray converters based on amorphous selenium (a-Se) and lead (Pb), representing both low and high-Z materials. When electron transport considerations can be neglected, excellent agreement (within 3%) is obtained for each metric over the entire diagnostic energy range in both a-Se and Pb detectors up to 30 cycles/mm, the highest frequency tested. The cascaded model overstates the DQE when the electron range cannot be ignored. This occurs at approximately two cycles/mm in a-Se at an incident photon energy of 80 keV, whereas in Pb, excellent agreement is obtained for the DQE over the entire diagnostic energy range. However, within the context of mammography (20 keV) and micro-computed tomography (40 keV), the effects of electron transport on the DQE are negligible compared to fluorescence reabsorption, which can lead to decreases of up to 30% and 20% in a-Se and Pb, respectively, at 20 keV; and 10% and 5%, respectively, at 40 keV. It is shown that when Swank noise is identified in a Fourier model, the Swank factor must be frequency dependent. This factor decreases

  20. Signal and noise transfer properties of photoelectric interactions in diagnostic x-ray imaging detectors

    SciTech Connect

    Hajdok, G.; Yao, J.; Battista, J. J.; Cunningham, I. A.

    2006-10-15

    Image quality in diagnostic x-ray imaging is ultimately limited by the statistical properties governing how, and where, x-ray energy is deposited in a detector. This in turn depends on the physics of the underlying x-ray interactions. In the diagnostic energy range (10-100 keV), most of the energy deposited in a detector is through photoelectric interactions. We present a theoretical model of the photoelectric effect that specifically addresses the statistical nature of energy absorption by photoelectrons, K and L characteristic x rays, and Auger electrons. A cascaded-systems approach is used that employs a complex structure of parallel cascades to describe signal and noise transfer through the photoelectric effect in terms of the modulation transfer function, Wiener noise power spectrum, and detective quantum efficiency (DQE). The model was evaluated by comparing results with Monte Carlo calculations for x-ray converters based on amorphous selenium (a-Se) and lead (Pb), representing both low and high-Z materials. When electron transport considerations can be neglected, excellent agreement (within 3%) is obtained for each metric over the entire diagnostic energy range in both a-Se and Pb detectors up to 30 cycles/mm, the highest frequency tested. The cascaded model overstates the DQE when the electron range cannot be ignored. This occurs at approximately two cycles/mm in a-Se at an incident photon energy of 80 keV, whereas in Pb, excellent agreement is obtained for the DQE over the entire diagnostic energy range. However, within the context of mammography (20 keV) and micro-computed tomography (40 keV), the effects of electron transport on the DQE are negligible compared to fluorescence reabsorption, which can lead to decreases of up to 30% and 20% in a-Se and Pb, respectively, at 20 keV; and 10% and 5%, respectively, at 40 keV. It is shown that when Swank noise is identified in a Fourier model, the Swank factor must be frequency dependent. This factor decreases

  1. Diagnostic imaging practices for children with suspected appendicitis evaluated at definitive care hospitals and their associated referral centers.

    PubMed

    Glass, Charity C; Saito, Jacqueline M; Sidhwa, Feroze; Cameron, Danielle B; Feng, Christina; Karki, Mahima; Abdullah, Fizan; Arca, Marjorie J; Goldin, Adam B; Barnhart, Douglas C; Zurakowski, David; Rangel, Shawn J

    2016-06-01

    The purpose of this study was to compare rates of ultrasound (US) and computed tomography (CT) for suspected appendicitis at hospitals able to provide definitive surgical care with those from their associated referral hospitals. A retrospective cohort study of children undergoing appendectomy using the Pediatric NSQIP Appendectomy Pilot Database (1/1/2013-8/31/2014) was performed. Imaging rates at the initial hospital of presentation were compared between groups after adjusting for differences in demographic characteristics. We identified 4859 patients from 28 definitive care hospitals, of which 35% underwent diagnostic imaging at a referral hospital prior to transfer (range: 20.3-70.4%). The overall odds of receiving a CT scan was 10.9-times greater (95% CI: 9.4-12.5) at referring hospitals compared to definitive care hospitals, and the odds were significantly higher for referral hospitals in 96% (27/28) of the geographic regions represented. The overall odds of an initial attempt at US prior to CT was 11.1 times greater (95% CI: 9.09-14.28), and the odds of receiving any ultrasound was 6.25-times greater (95% CI: 5.26-7.14) at definitive care hospitals compared to referral hospitals. Children initially evaluated for suspected appendicitis at referring hospitals are much more likely to receive a diagnostic CT, and those imaged with CT are much less likely to receive an US as the initial diagnostic test. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Method to directly radiolabel antibodies for diagnostic imaging and therapy

    SciTech Connect

    Thakur, M.L.

    1994-05-03

    The invention is a novel method and kit for directly radiolabeling proteins such as antibodies or antibody fragments for diagnostic and therapeutic purposes. The method comprises incubating a protein-containing solution with a solution of sodium ascorbate; adding a required quantity of reduced radionuclide to the incubated protein. A kit is also provided wherein the protein and/or reducing agents may be in lyophilized form. No Drawings

  3. Method to directly radiolabel antibodies for diagnostic imaging and therapy

    DOEpatents

    Thakur, Mathew L.

    1991-01-01

    The invention is a novel method and kit for directly radiolabeling proteins such as antibodies or antibody fragments for diagnostic and therapeutic purposes. The method comprises incubating a protein-containing solution with a solution of sodium ascorbate; adding a required quantity of reduced radionuclide to the incubated protein. A kit is also provided wherein the protein and/or reducing agents may be in lyophilized form.

  4. Method to directly radiolabel antibodies for diagnostic imaging and therapy

    DOEpatents

    Thakur, Mathew L.

    1994-01-01

    The invention is a novel method and kit for directly radiolabeling proteins such as antibodies or antibody fragments for diagnostic and therapeutic purposes. The method comprises incubating a protein-containing solution with a solution of sodium ascorbate; adding a required quantity of reduced radionuclide to the incubated protein. A kit is also provided wherein the protein and/or reducing agents may be in lyophilized form.

  5. MDIS (medical diagnostic imaging support) workstation issues: clinical perspective

    NASA Astrophysics Data System (ADS)

    Smith, Donald V.; Smith, Suzy; Cawthon, Michael A.

    1991-05-01

    A joint DoD effort is in the final stages of contract acquisition to achieve a ''filmless'' hospital environment in the near future. Success of implementation lays to a large degree on an effective image workstation. This paper will discuss soft copy image display (SCID) of the MDIS system including hardware and software.

  6. Vertical root fracture: Biological effects and accuracy of diagnostic imaging methods

    PubMed Central

    Baageel, Turki M.; Allah, Emad Habib; Bakalka, Ghaida T.; Jadu, Fatima; Yamany, Ibrahim; Jan, Ahmed M.; Bogari, Dania F.; Alhazzazi, Turki Y.

    2016-01-01

    This review assessed the most up-to-date literature on the accuracy of detecting vertical root fractures (VRFs] using the currently available diagnostic imaging methods. In addition, an overview of the biological and clinical aspects of VRFs will also be discussed. A systematic review of the literature was initiated in December of 2015 and then updated in May of 2016. The electronic databases searched included PubMed, Emabse, Ovid, and Google Scholar. An assessment of the methodological quality was performed using a modified version of the quality assessment of diagnostic accuracy studies tool. Twenty-two studies were included in this systematic review after applying specific inclusion and exclusion criteria. Of those, 12 favored using cone beam computed tomography (CBCT) for detecting VRF as compared to periapical radiographs, whereas 5 reported no differences between the two methods. The remaining 5 studies confirmed the advantages associated with using CBCT when diagnosing VRF and described the parameters and limitations associated with this method, but they were not comparative studies. In conclusion, overwhelming evidence suggests that the use of CBCT is a preferred method for detecting VRFs. Nevertheless, additional well controlled and high quality studies are needed to produce solid evidence and guidelines to support the routine use of CBCT in the diagnosis of VRFs as a standard of care. PMID:27652254

  7. Computed Tomography is Diagnostic in the Cervical Imaging of Helmeted Football Players With Shoulder Pads

    PubMed Central

    Rothman, Michael; Foley, Jack; Heller, Michael

    2004-01-01

    Objective: Prospective, observational case series evaluating the value of cervical spine computed tomography (CT) scans in the initial evaluation of a helmeted football player with suspected cervical spine injury. Subjects: Five asymptomatic male football players, fully equipped and immobilized on a backboard. Design: Multiple 3.0-mm, helically acquired, axially displayed CT images of the cervical spine were obtained from the skull base inferiorly through T1, with images filmed at soft tissue and bone windows. Sagittal and coronal reformatted images were performed. Software was used to minimize metallic artifact. Measurements: All series were reviewed by a Board-certified neuroradiologist for image clarity and diagnostic capability. Results: Lateral scout films demonstrated mild segmental degradation, depending on the location of the metallic snaps overlying the spine. Anteroposterior scout films and bone window images were of diagnostic quality. The soft tissue windows showed minimal localized artifact occurring at the same levels as in the lateral scout views. This minimal beam-hardening streak artifact did not affect the diagnostic quality of the soft tissue windows. Reconstructed images were uniformly of clinical diagnostic quality. Discussion: When CT scans were reviewed as a unit, sufficient information was available to allow reliable clinical decisions about the helmeted football player. In light of recent publications demonstrating the difficulty of obtaining adequate radiographs to evaluate cervical spine injury in equipped football players, helmeted athletes may undergo CT scanning without any significant diagnostic limitations. PMID:15496989

  8. Power calculation for comparing diagnostic accuracies in a multi-reader, multi-test design.

    PubMed

    Kim, Eunhee; Zhang, Zheng; Wang, Youdan; Zeng, Donglin

    2014-12-01

    Receiver operating characteristic (ROC) analysis is widely used to evaluate the performance of diagnostic tests with continuous or ordinal responses. A popular study design for assessing the accuracy of diagnostic tests involves multiple readers interpreting multiple diagnostic test results, called the multi-reader, multi-test design. Although several different approaches to analyzing data from this design exist, few methods have discussed the sample size and power issues. In this article, we develop a power formula to compare the correlated areas under the ROC curves (AUC) in a multi-reader, multi-test design. We present a nonparametric approach to estimate and compare the correlated AUCs by extending DeLong et al.'s (1988, Biometrics 44, 837-845) approach. A power formula is derived based on the asymptotic distribution of the nonparametric AUCs. Simulation studies are conducted to demonstrate the performance of the proposed power formula and an example is provided to illustrate the proposed procedure.

  9. A promising diagnostic method: Terahertz pulsed imaging and spectroscopy

    PubMed Central

    Sun, Yiwen; Sy, Ming Yiu; Wang, Yi-Xiang J; Ahuja, Anil T; Zhang, Yuan-Ting; Pickwell-MacPherson, Emma

    2011-01-01

    The terahertz band lies between the microwave and infrared regions of the electromagnetic spectrum. This radiation has very low photon energy and thus it does not pose any ionization hazard for biological tissues. It is strongly attenuated by water and very sensitive to water content. Unique absorption spectra due to intermolecular vibrations in this region have been found in different biological materials. These unique features make terahertz imaging very attractive for medical applications in order to provide complimentary information to existing imaging techniques. There has been an increasing interest in terahertz imaging and spectroscopy of biologically related applications within the last few years and more and more terahertz spectra are being reported. This paper introduces terahertz technology and provides a short review of recent advances in terahertz imaging and spectroscopy techniques, and a number of applications such as molecular spectroscopy, tissue characterization and skin imaging are discussed. PMID:21512652

  10. A Methodology for Anatomic Ultrasound Image Diagnostic Quality Assessment.

    PubMed

    Hemmsen, Martin Christian; Lange, Theis; Brandt, Andreas Hjelm; Nielsen, Michael Bachmann; Jensen, Jorgen Arendt

    2017-01-01

    This paper discusses the methods for the assessment of ultrasound image quality based on our experiences with evaluating new methods for anatomic imaging. It presents a methodology to ensure a fair assessment between competing imaging methods using clinically relevant evaluations. The methodology is valuable in the continuing process of method optimization and guided development of new imaging methods. It includes a three phased study plan covering from initial prototype development to clinical assessment. Recommendations to the clinical assessment protocol, software, and statistical analysis are presented. Earlier uses of the methodology has shown that it ensures validity of the assessment, as it separates the influences between developer, investigator, and assessor once a research protocol has been established. This separation reduces confounding influences on the result from the developer to properly reveal the clinical value. This paper exemplifies the methodology using recent studies of synthetic aperture sequential beamforming tissue harmonic imaging.

  11. A report on the Academic Emergency Medicine 2015 consensus conference "Diagnostic imaging in the emergency department: a research agenda to optimize utilization".

    PubMed

    Gunn, Martin L; Marin, Jennifer R; Mills, Angela M; Chong, Suzanne T; Froemming, Adam T; Johnson, Jamlik O; Kumaravel, Manickam; Sodickson, Aaron D

    2016-08-01

    In May 2015, the Academic Emergency Medicine consensus conference "Diagnostic imaging in the emergency department: a research agenda to optimize utilization" was held. The goal of the conference was to develop a high-priority research agenda regarding emergency diagnostic imaging on which to base future research. In addition to representatives from the Society of Academic Emergency Medicine, the multidisciplinary conference included members of several radiology organizations: American Society for Emergency Radiology, Radiological Society of North America, the American College of Radiology, and the American Association of Physicists in Medicine. The specific aims of the conference were to (1) understand the current state of evidence regarding emergency department (ED) diagnostic imaging utilization and identify key opportunities, limitations, and gaps in knowledge; (2) develop a consensus-driven research agenda emphasizing priorities and opportunities for research in ED diagnostic imaging; and (3) explore specific funding mechanisms available to facilitate research in ED diagnostic imaging. Through a multistep consensus process, participants developed targeted research questions for future research in six content areas within emergency diagnostic imaging: clinical decision rules; use of administrative data; patient-centered outcomes research; training, education, and competency; knowledge translation and barriers to imaging optimization; and comparative effectiveness research in alternatives to traditional computed tomography use.

  12. A comparative study of the diagnostic capabilities of 2D plain radiograph and 3D cone beam CT sialography

    PubMed Central

    Jadu, FM; Lam, EWN

    2013-01-01

    Objective The aim of this study was to compare the diagnostic capabilities of two-dimensional sialography with a novel three-dimensional technique using cone beam CT (CBCT). Methods 47 subjects underwent parotid or submandibular gland sialography over a 2 year period using both plain imaging and CBCT. Both image sets were anonymized and independently reviewed by three certified oral and maxillofacial radiologists blinded to the clinical data. McNemar's χ2 test was used to determine differences between the two modalities for feature visualization and interpretation. Results CBCT outperformed plain imaging with respect to visualization of the gland parenchyma (p < 0.001) and identification of sialoliths (p = 0.02). Plain imaging outperformed CBCT for the identification of strictures (p = 0.04); however, the negative per cent agreement (“specificity”) between the two imaging modalities was 100%. Although both imaging modalities performed equally in identifying normal and abnormal sialographic examinations, CBCT demonstrated a high negative per cent agreement for normal glands and a high positive per cent agreement (“sensitivity”) for abnormal glands with inflammatory changes. Conclusion CBCT sialography allowed better visualization of gland parenchyma and identification of sialoliths. The high negative per cent agreement for strictures suggests that, if strictures are identified on CBCT images, then obstruction can be ruled in. Relative to plain images, the high negative per cent agreement for normal glands suggests that, if an abnormal finding is detected on CBCT images, then disease can be ruled in, and the high positive per cent agreement for glands with inflammatory changes suggests that inflammation can be ruled out if these changes are not seen on CBCT images. PMID:23253564

  13. Motion tracking in infrared imaging for quantitative medical diagnostic applications

    NASA Astrophysics Data System (ADS)

    Cheng, Tze-Yuan; Herman, Cila

    2014-01-01

    In medical applications, infrared (IR) thermography is used to detect and examine the thermal signature of skin abnormalities by quantitatively analyzing skin temperature in steady state conditions or its evolution over time, captured in an image sequence. However, during the image acquisition period, the involuntary movements of the patient are unavoidable, and such movements will undermine the accuracy of temperature measurement for any particular location on the skin. In this study, a tracking approach using a template-based algorithm is proposed, to follow the involuntary motion of the subject in the IR image sequence. The motion tacking will allow to associate a temperature evolution to each spatial location on the body while the body moves relative to the image frame. The affine transformation model is adopted to estimate the motion parameters of the template image. The Lucas-Kanade algorithm is applied to search for the optimized parameters of the affine transformation. A weighting mask is incorporated into the algorithm to ensure its tracking robustness. To evaluate the feasibility of the tracking approach, two sets of IR image sequences with random in-plane motion were tested in our experiments. A steady-state (no heating or cooling) IR image sequence in which the skin temperature is in equilibrium with the environment was considered first. The thermal recovery IR image sequence, acquired when the skin is recovering from 60-s cooling, was the second case analyzed. By proper selection of the template image along with template update, satisfactory tracking results were obtained for both IR image sequences. The achieved tracking accuracies are promising in terms of satisfying the demands imposed by clinical applications of IR thermography.

  14. Emergency CT brain: preliminary interpretation with a tablet device: image quality and diagnostic performance of the Apple iPad.

    PubMed

    Mc Laughlin, Patrick; Neill, Siobhan O; Fanning, Noel; Mc Garrigle, Anne Marie; Connor, Owen J O; Wyse, Gerry; Maher, Michael M

    2012-04-01

    Tablet devices have recently been used in radiological image interpretation because they have a display resolution comparable to desktop LCD monitors. We identified a need to examine tablet display performance prior to their use in preliminary interpretation of radiological images. We compared the spatial and contrast resolution of a commercially available tablet display with a diagnostic grade 2 megapixel monochrome LCD using a contrast detail phantom. We also recorded reporting discrepancies, using the ACR RADPEER system, between preliminary interpretation of 100 emergency CT brain examinations on the tablet display and formal review on a diagnostic LCD. The iPad display performed inferiorly to the diagnostic monochrome display without the ability to zoom. When the software zoom function was enabled on the tablet device, comparable contrast detail phantom scores of 163 vs 165 points were achieved. No reporting discrepancies were encountered during the interpretation of 43 normal examinations and five cases of acute intracranial hemorrhage. There were seven RADPEER2 (understandable) misses when using the iPad display and 12 with the diagnostic LCD. Use of software zoom in the tablet device improved its contrast detail phantom score. The tablet allowed satisfactory identification of acute CT brain findings, but additional research will be required to examine the cause of "understandable" reporting discrepancies that occur when using tablet devices.

  15. Radiation exposure in urology: a genitourinary catalogue for diagnostic imaging.

    PubMed

    Neisius, Andreas; Wang, Agnes J; Wang, Chu; Nguyen, Giao; Tsivian, Matvey; Kuntz, Nicholas J; Astroza, Gastón M; Lowry, Carolyn; Toncheva, Greta; Yoshizumi, Terry T; Preminger, Glenn M; Ferrandino, Michael N; Lipkin, Michael E

    2013-12-01

    Computerized tomography use increased exponentially in the last 3 decades, and it is commonly used to evaluate many urological conditions. Ionizing radiation exposure from medical imaging is linked to the risk of malignancy. We measured the organ and calculated effective doses of different studies to determine whether the dose-length product method is an accurate estimation of radiation exposure. An anthropomorphic male phantom validated for human organ dosimetry measurements was used to determine radiation doses. High sensitivity metal oxide semiconductor field effect transistor dosimeters were placed at 20 organ locations to measure specific organ doses. For each study the phantom was scanned 3 times using our institutional protocols. Organ doses were measured and effective doses were calculated on dosimetry. Effective doses measured by a metal oxide semiconductor field effect transistor dosimeter were compared to calculated effective doses derived from the dose-length product. The mean±SD effective dose on dosimetry for stone protocol, chest and abdominopelvic computerized tomography, computerized tomography urogram and renal cell carcinoma protocol computerized tomography was 3.04±0.34, 4.34±0.27, 5.19±0.64, 9.73±0.71 and 11.42±0.24 mSv, respectively. The calculated effective dose for these studies Was 3.33, 2.92, 5.84, 9.64 and 10.06 mSv, respectively (p=0.8478). The effective dose varies considerable for different urological computerized tomography studies. Renal stone protocol computerized tomography shows the lowest dose, and computerized tomography urogram and the renal cell carcinoma protocol accumulate the highest effective doses. The calculated effective dose derived from the dose-length product is a reasonable estimate of patient radiation exposure. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  16. Diagnostic Performance of Diffusion-weighted Magnetic Resonance Imaging in Bone Malignancy

    PubMed Central

    Liu, Li-Peng; Cui, Long-Biao; Zhang, Xin-Xin; Cao, Jing; Chang, Ning; Tang, Xing; Qi, Shun; Zhang, Xiao-Liang; Yin, Hong; Zhang, Jian

    2015-01-01

    Abstract Current state-of-the-art nuclear medicine imaging methods (such as PET/CT or bone scintigraphy) may have insufficient sensitivity for predicting bone tumor, and substantial exposure to ionizing radiation is associated with the risk of secondary cancer development. Diffusion-weighted MRI (DW-MRI) is radiation free and requires no intravenous contrast media, and hence is more suitable for population groups that are vulnerable to ionizing radiation and/or impaired renal functions. This meta-analysis was conducted to investigate whether whole-body DW-MRI is a viable means in differentiating bone malignancy. Medline and Embase databases were searched from their inception to May 2015 without language restriction for studies evaluating DW-MRI for detection of bone lesions. Methodological quality was assessed by the quality assessment of diagnostic studies (QUADAS-2) instrument. Sensitivities, specificities, diagnostic odds ratio (DOR), and areas under the curve (AUC) were used as measures of the diagnostic accuracy. We combined the effects by using the random-effects mode. Potential threshold effects and publication bias were investigated. We included data from 32 studies with 1507 patients. The pooled sensitivity, specificity, and AUC were 0.95 (95% CI, 0.90–0.97), 0.92 (95% CI, 0.88–0.95), and 0.98 on a per-patient basis, and they were 0.91 (95% CI, 0.87–0.94), 0.94 (95% CI, 0.90–0.96), and 0.97 on a per-lesion basis. In subgroup analysis, there is no statistical significance found in the sensitivity and specificity of using DWI only and DWI combined with other morphological or functional imaging sequence in both basis (P > 0.05). A b value of 750 to 1000 s/mm2 enables higher AUC and DOR for whole-body imaging purpose when compared with other values in both basis either (P < 0.01). The ROC space did not show a curvilinear trend of points and a threshold effect was not observed. According to the Deek's plots, there was no publication bias on

  17. First Steps Toward Incorporating Image Based Diagnostics Into Particle Accelerator Control Systems Using Convolutional Neural Networks

    SciTech Connect

    Edelen, A. L.; Biedron, S. G.; Milton, S. V.; Edelen, J. P.

    2016-12-16

    At present, a variety of image-based diagnostics are used in particle accelerator systems. Often times, these are viewed by a human operator who then makes appropriate adjustments to the machine. Given recent advances in using convolutional neural networks (CNNs) for image processing, it should be possible to use image diagnostics directly in control routines (NN-based or otherwise). This is especially appealing for non-intercepting diagnostics that could run continuously during beam operation. Here, we show results of a first step toward implementing such a controller: our trained CNN can predict multiple simulated downstream beam parameters at the Fermilab Accelerator Science and Technology (FAST) facility's low energy beamline using simulated virtual cathode laser images, gun phases, and solenoid strengths.

  18. Necrotizing fasciitis: contribution and limitations of diagnostic imaging.

    PubMed

    Malghem, Jacques; Lecouvet, Frédéric E; Omoumi, Patrick; Maldague, Baudouin E; Vande Berg, Bruno C

    2013-03-01

    Necrotizing fasciitis is a rare, rapidly spreading, deep-seated infection causing thrombosis of the blood vessels located in the fascia. Necrotizing fasciitis is a surgical emergency. The diagnosis typically relies on clinical findings of severe sepsis and intense pain, although subacute forms may be difficult to recognize. Imaging studies can help to differentiate necrotizing fasciitis from infections located more superficially (dermohypodermitis). The presence of gas within the necrotized fasciae is characteristic but may be lacking. The main finding is thickening of the deep fasciae due to fluid accumulation and reactive hyperemia, which can be visualized using computed tomography and, above all, magnetic resonance imaging (high signal on contrast-enhanced T1 images and T2 images, best seen with fat saturation). These findings lack specificity, as they can be seen in non-necrotizing fasciitis and even in non-inflammatory conditions. Signs that support a diagnosis of necrotizing fasciitis include extensive involvement of the deep intermuscular fascias (high sensitivity but low specificity), thickening to more than 3mm, and partial or complete absence on post-gadolinium images of signal enhancement of the thickened fasciae (fairly high sensitivity and specificity). Ultrasonography is not recommended in adults, as the infiltration of the hypodermis blocks ultrasound transmission. Thus, imaging studies in patients with necrotizing fasciitis may be challenging to interpret. Although imaging may help to confirm deep tissue involvement and to evaluate lesion spread, it should never delay emergency surgical treatment in patients with established necrotizing fasciitis.

  19. Diagnostic accuracy of susceptibility-weighted magnetic resonance imaging for the evaluation of pineal gland calcification

    PubMed Central

    Böker, Sarah M.; Bender, Yvonne Y.; Diederichs, Gerd; Fallenberg, Eva M.; Wagner, Moritz; Hamm, Bernd; Makowski, Marcus R.

    2017-01-01

    Objectives To determine the diagnostic performance of susceptibility-weighted magnetic resonance imaging (SWMR) for the detection of pineal gland calcifications (PGC) compared to conventional magnetic resonance imaging (MRI) sequences, using computed tomography (CT) as a reference standard. Methods 384 patients who received a 1.5 Tesla MRI scan including SWMR sequences and a CT scan of the brain between January 2014 and October 2016 were retrospectively evaluated. 346 patients were included in the analysis, of which 214 showed PGC on CT scans. To assess correlation between imaging modalities, the maximum calcification diameter was used. Sensitivity and specificity and intra- and interobserver reliability were calculated for SWMR and conventional MRI sequences. Results SWMR reached a sensitivity of 95% (95% CI: 91%-97%) and a specificity of 96% (95% CI: 91%-99%) for the detection of PGC, whereas conventional MRI achieved a sensitivity of 43% (95% CI: 36%-50%) and a specificity of 96% (95% CI: 91%-99%). Detection rates for calcifications in SWMR and conventional MRI differed significantly (95% versus 43%, p<0.001). Diameter measurements between SWMR and CT showed a close correlation (R2 = 0.85, p<0.001) with a slight but not significant overestimation of size (SWMR: 6.5 mm ± 2.5; CT: 5.9 mm ± 2.4, p = 0.02). Interobserver-agreement for diameter measurements was excellent on SWMR (ICC = 0.984, p < 0.0001). Conclusions Combining SWMR magnitude and phase information enables the accurate detection of PGC and offers a better diagnostic performance than conventional MRI with CT as a reference standard. PMID:28278291

  20. Diagnostic accuracy of susceptibility-weighted magnetic resonance imaging for the evaluation of pineal gland calcification.

    PubMed

    Adams, Lisa C; Böker, Sarah M; Bender, Yvonne Y; Diederichs, Gerd; Fallenberg, Eva M; Wagner, Moritz; Hamm, Bernd; Makowski, Marcus R

    2017-01-01

    To determine the diagnostic performance of susceptibility-weighted magnetic resonance imaging (SWMR) for the detection of pineal gland calcifications (PGC) compared to conventional magnetic resonance imaging (MRI) sequences, using computed tomography (CT) as a reference standard. 384 patients who received a 1.5 Tesla MRI scan including SWMR sequences and a CT scan of the brain between January 2014 and October 2016 were retrospectively evaluated. 346 patients were included in the analysis, of which 214 showed PGC on CT scans. To assess correlation between imaging modalities, the maximum calcification diameter was used. Sensitivity and specificity and intra- and interobserver reliability were calculated for SWMR and conventional MRI sequences. SWMR reached a sensitivity of 95% (95% CI: 91%-97%) and a specificity of 96% (95% CI: 91%-99%) for the detection of PGC, whereas conventional MRI achieved a sensitivity of 43% (95% CI: 36%-50%) and a specificity of 96% (95% CI: 91%-99%). Detection rates for calcifications in SWMR and conventional MRI differed significantly (95% versus 43%, p<0.001). Diameter measurements between SWMR and CT showed a close correlation (R2 = 0.85, p<0.001) with a slight but not significant overestimation of size (SWMR: 6.5 mm ± 2.5; CT: 5.9 mm ± 2.4, p = 0.02). Interobserver-agreement for diameter measurements was excellent on SWMR (ICC = 0.984, p < 0.0001). Combining SWMR magnitude and phase information enables the accurate detection of PGC and offers a better diagnostic performance than conventional MRI with CT as a reference standard.

  1. Use and Accuracy of Diagnostic Imaging by Hospital Type in Pediatric Appendicitis

    PubMed Central

    Yan, Yan; Evashwick, Thomas W.; Warner, Brad W.; Tarr, Phillip I.

    2013-01-01

    OBJECTIVE: Accurate, timely diagnosis of pediatric appendicitis minimizes unnecessary operations and treatment delays. Preoperative abdominal-pelvic computed tomography (CT) scan is sensitive and specific for appendicitis; however, concerns regarding radiation exposure in children obligate scrutiny of CT use. Here, we characterize recent preoperative imaging use and accuracy among pediatric appendectomy subjects. METHODS: We retrospectively reviewed children who underwent operations for presumed appendicitis at a single tertiary-care children’s hospital and examined preoperative CT and ultrasound use with subject characteristics. Preoperative imaging accuracy was compared with postoperative and histologic diagnosis as the reference standard. RESULTS: Most children (395/423, 93.4%) who underwent an operation for appendicitis during 2009–2010 had preoperative imaging. Final diagnoses included normal appendix (7.3%) and perforated appendicitis (23.6%). In multivariable analysis, initial evaluation at a community hospital versus the children’s hospital was associated with 4.4-fold higher odds of obtaining a preoperative CT scan (P = .002), whereas preoperative ultrasound was less likely (odds ratio 0.20; P = .003). Ultrasound and CT sensitivities for appendicitis were diminished for studies performed at community hospitals compared with the children’s hospital. Girls were 4.5-fold more likely to undergo both ultrasound and CT scans and were associated with lower ultrasound sensitivity for appendicitis. CONCLUSIONS: Widespread preoperative imaging did not eliminate unnecessary pediatric appendectomies. Controlling for factors potentially associated with referral bias, a CT scan was more likely to be performed in children initially evaluated at community hospitals compared with the children’s hospital. Broadly-applicable strategies to systematically maximize diagnostic accuracy for childhood appendicitis, while minimizing ionizing radiation exposure, are

  2. New concepts in standing advanced diagnostic equine imaging.

    PubMed

    Porter, Erin G; Werpy, Natasha M

    2014-04-01

    This article addresses the clinical application of magnetic resonance imaging (MRI) and computed tomography (CT) as applied to the standing equine patient. This discussion includes the logistics, advantages, disadvantages, and limitations of imaging a standing horse. In addition, a brief review is given of the physics of these modalities as applied in clinical practice, and the currently available hardware and software required by these techniques for image acquisition and artifact reduction. The appropriate selection of clinical cases for standing MRI and CT is reviewed, focusing on cases that are capable of undergoing standing surgeries following lesion diagnosis.

  3. Advanced radiation measurement techniques in diagnostic radiology and molecular imaging.

    PubMed

    Del Guerra, Alberto; Belcari, Nicola; Llacer, Gabriela Llosa; Marcatili, Sara; Moehrs, Sascha; Panetta, Daniele

    2008-01-01

    This paper reports some technological advances recently achieved in the fields of micro-CT and small animal PET instrumentation. It highlights a balance between image-quality improvement and dose reduction. Most of the recent accomplishments in these fields are due to the use of novel imaging sensors such as CMOS-based X-ray detectors and silicon photomultipliers (SiPM). Some of the research projects carried out at the University of Pisa for the development of such advanced radiation imaging technology are also described.

  4. Forensic Techniques for Image Source Classification: A Comparative Study

    NASA Astrophysics Data System (ADS)

    Delp, Edward J.

    Digital images can be captured or generated by a variety of sources including digital cameras, scanners and computer graphics softwares. In many cases it is important to be able to determine the source of a digital image such as for criminal and forensic investigation. Based on their originating mechanism digital images can be classified into three classes: digital camera images, scanner generated images and computer-graphics generated images. Image source classification is helpful as a first step for identifying the unique device or system which produced the image. This paper presents a survey of different methods for solving image source classification problem, some improvements over them and compares their performance in a common framework. As expected with the advances in computer graphics techniques, artificial images are becoming closer and closer to the natural ones and harder to distinguish by human visual system. Hence, the methods based on characteristics of image generating process are more successful than those based on image content.

  5. Diagnostic Accuracy of Lumbosacral Spine Magnetic Resonance Image Reading by Chiropractors, Chiropractic Radiologists, and Medical Radiologists.

    PubMed

    de Zoete, Annemarie; Ostelo, Raymond; Knol, Dirk L; Algra, Paul R; Wilmink, Jan T; van Tulder, Maurits W

    2015-06-01

    A cross-sectional diagnostic accuracy study was conducted in 2 sessions. It is important to know whether it is possible to accurately detect "specific findings" on lumbosacral magnetic resonance (MR) images and whether the results of different observers are comparable. Health care providers frequently use magnetic resonance imaging in the diagnostic process of patients with low back pain. The use of MR scans is increasing. This leads to an increase in costs and to an increase in risk of inaccurately labeling patients with an anatomical diagnosis that might not be the actual cause of symptoms. A set of 300 blinded MR images was read by medical radiologists, chiropractors, and chiropractic radiologists in 2 sessions. Each assessor read 100 scans in round 1 and 50 scans in round 2. The reference test was an expert panel.For all analyses, the magnetic resonance imaging findings were dichotomized into "specific findings" or "no specific findings." For the agreement, percentage agreement and κ values were calculated and for validity, sensitivity, and specificity. Sensitivity analysis was done for classifications A and B (prevalence of 31% and 57%, respectively). The intraobserver κ values for chiropractors, chiropractic radiologists, and medical radiologists were 0.46, 0.49, and 0.69 for A and 0.55, 0.75, and 0.64 for B, respectively.The interobserver κ values were lowest for chiropractors (0.28 for A, 0.37 for B) and highest for chiropractic radiologists (0.50 for A, 0.49 for B).The sensitivities of the medical radiologists, chiropractors, and chiropractic radiologists were 0.62, 0.71, and 0.75 for A and 0.70, 0.74, 0.84 for B, respectively.The specificities of medical radiologists, chiropractic radiologists, and chiropractors were 0.82, 0.77, and 0.70 for A and 0.74, 0.52, and 0.61 for B, respectively. Agreement and validity of MR image readings of chiropractors and chiropractic and medical radiologists is modest at best. This study supports recommendations in

  6. Comparing the diagnostic performance of MRI versus CT in the evaluation of acute nontraumatic abdominal pain during pregnancy.

    PubMed

    Baron, Keren Tuvia; Arleo, Elizabeth Kagan; Robinson, Christopher; Sanelli, Pina C

    2012-12-01

    The objectives of this study were to document the utilization of MRI compared with CT in pregnant patients presenting with acute nontraumatic abdominal pain at our institution and to compare the diagnostic performance of the two modalities. A retrospective review identified all pregnant patients at our institution who had MRI or CT exams of the abdomen and/or pelvis for acute nontraumatic abdominal pain over a 3-year period from January 2008 through December 2010. The imaging diagnoses were compared with pathologic data or operative findings as the primary reference standard or with clinical follow-up and laboratory data as the secondary reference standard. Patients without surgically proven diagnoses were followed clinically until delivery, when possible. Ninety-four pregnant patients were included in this study: 61 MRI exams were performed in 57 patients, 44 CT exams were performed in 43 patients (including six patients who had both), and 72 patients (77 %) had ultrasound prior to cross-sectional imaging, with the appendix specifically assessed in 25 patients but visualized in only two of them. Of 61 MRI exams, 24 were considered positive for imaging diagnoses, 33 were negative, and 4 were equivocal. Of 44 CT exams, 24 were positive and 20 were negative. The test characteristics for MRI and CT in the diagnosis of acute abdominal pain were as follows: sensitivity 91 and 88 %, specificity 85 and 90 %, positive predictive value 81 and 91 %, negative predictive value 94 and 8 5 %, and diagnostic accuracy 88 and 88 %, respectively. Differences were not statistically significant (p value = 1). The majority of MRIs (34/61 = 56 %) were read by emergency radiologists. MRI and CT performed equally well in the evaluation of acute nontraumatic abdominal pain during pregnancy. Given its lack of ionizing radiation, MRI may be preferable. Given that the majority of MRIs were read by radiologists specializing in emergency imaging, this is a technique that emergency

  7. Comparing Phytophthora ramorum diagnostic protocols for the national Sudden Oak death stream monitoring program

    Treesearch

    W. Sutton; E.M. Hansen; P. Reeser; A. Kanaskie

    2008-01-01

    Oregon was a participant in the pilot test of the national stream monitoring protocol for SOD. We routinely and continuously monitor about 50 streams in and near the SOD quarantine area in southwest Oregon using foliage baits. For the national protocol, we added six additional streams beyond the area of known infestation, and compared results from different diagnostic...

  8. [EOS imaging acquisition system : 2D/3D diagnostics of the skeleton].

    PubMed

    Tarhan, T; Froemel, D; Meurer, A

    2015-12-01

    The application spectrum of the EOS imaging acquisition system is versatile. It is especially useful in the diagnostics and planning of corrective surgical procedures in complex orthopedic cases. The application is indicated when assessing deformities and malpositions of the spine, pelvis and lower extremities. It can also be used in the assessment and planning of hip and knee arthroplasty. For the first time physicians have the opportunity to conduct examinations of the whole body under weight-bearing conditions in order to anticipate the effects of a planned surgical procedure on the skeletal system as a whole and therefore on the posture of the patient. Compared to conventional radiographic examination techniques, such as x-ray or computed tomography, the patient is exposed to much less radiation. Therefore, the pediatric application of this technique can be described as reasonable.

  9. Application of a three-dimensional display in diagnostic imaging.

    PubMed

    Baxter, B; Hitchner, L E; Anderson, R E

    1982-10-01

    An autostereoscopic viewing device for tomographic scans that allows a physician to examine multiple computed tomography sections with each section properly positioned in three dimensions has been constructed and tested. Images produced on the device allow the observer to utilize both motion parallax and stereoscopic depth cues as if viewing a real three-dimensional (3D) object. These 3D images can be very striking because of the ease with which one can form a true impression of depth relationships. We describe operating principles of the viewing device and the appearance of images produced on it. Stereo photographs made from 3D images displayed on the device are included to illustrate potential applications and problems.

  10. 1895-1995: diagnostic imaging in its first century.

    PubMed

    Yochum, T R

    1995-01-01

    A brief historical review of the discovery of X-ray by Wilhelm Konrad Roentgen on November 9, 1895, is presented. This synopsis discusses the evolution of X-ray imaging from the primitive Crookes x-ray tube to the state-of-the-art high-frequency generators. Technological advancements from fluoroscopy to plain films, nuclear medicine, computed tomography and magnetic resonance imaging, along with changes in X-ray film and intensifying screens, are also provided. A concise overview of chiropractic radiology and the introduction of X-ray into the chiropractic curriculum, first at Palmer College and then at other colleges is presented. Historical recognition of the development of the American Chiropractic Board of Radiology (ACBR), its founding fathers and its certification program for training chiropractic radiologists is reviewed. General comments pointing to computerized digital imaging as the filmless imaging of the future are offered.

  11. Systems diagnostics: the systems approach to molecular imaging.

    PubMed

    Lee, Daniel Y; Li, King C P

    2009-08-01

    Molecular imaging has emerged as a powerful technology that has already changed the practice of modern medicine. During this same period, the monumental genome project has sequenced man's entire genetic content. Now the postgenomic aim is to understand the dynamic interactions of the encoded components and their regulatory mechanisms. Molecular imaging is well positioned to play a major role in this massive effort as we move toward a comprehensive paradigm for assessing health and disease.

  12. [Contrast-enhanced Ultrasound in Diagnostic Imaging of Muscle Injuries: Perfusion Imaging in the Early Arterial Phase].

    PubMed

    Hotfiel, T; Carl, H D; Swoboda, B; Engelhardt, M; Heinrich, M; Strobel, D; Wildner, D

    2016-03-01

    Ultrasound is a standard procedure widely used in the diagnostic investigation of muscle injuries and widely described in the literature. Its advantages include rapid availability, cost effectiveness and the possibility to perform a real-time dynamic examination with the highest possible spatial resolution. In the diagnostic work-up of minor lesions (muscle stiffness, muscle strain), plain ultrasound has so far been inferior to MRI. The case presented by us is an example of the possibilities offered by contrast-enhanced ultrasound (CEUS) in the imaging of muscle injuries compared with plain B-mode image ultrasound and MRI imaging of the affected region. This case report is about a high-performance football player who sustained a muscle injury. He underwent an ultrasound examination (S 2000, 9L4 Probe, Siemens, Germany), which was performed simultaneously in the conventional and contrast-enhanced mode at the level of the lesion. An intravenous bolus injection of 4.8 ml of intravascular contrast agent (SonoVue(®), Bracco, Italy) was given via a cubital intravenous line. After that, the distribution of contrast agent was visualised in the early arterial phase. In addition, a plain magnetic resonance imaging scan of both thighs was performed for reference. On conventional ultrasound, the lesion was not clearly distinguishable from neighbouring tissue, whereas contrast-enhanced ultrasound demonstrated a well delineated, circumscribed area of impaired perfusion with hypoenhancement compared with the surrounding muscles at the clinical level of the lesion in the arterial wash-in phase (0-30 sec, after intravenous administration). The MRI scan revealed an edema signal with perifascial fluid accumulation in the corresponding site. The use of intravascular contrast agent enabled the sensitive detection of a minor injury by ultrasound for the first time. An intramuscular edema seen in the MRI scan showed a functional arterial perfusion impairment on ultrasound, which was

  13. Quantitative validation of anti-PTBP1 antibody for diagnostic neuropathology use: Image analysis approach.

    PubMed

    Goceri, Evgin; Goksel, Behiye; Elder, James B; Puduvalli, Vinay K; Otero, Jose J; Gurcan, Metin N

    2016-12-26

    Traditional diagnostic neuropathology relies on subjective interpretation of visual data obtained from a brightfield microscopy. This approach causes high variability, unsatisfactory reproducibility, and inability for multiplexing even among experts. These problems may affect patient outcomes and confound clinical decision-making. Also, standard histological processing of pathological specimens leads to auto-fluorescence and other artifacts, a reason why fluorescent microscopy is not routinely implemented in diagnostic pathology. To overcome these problems, objective and quantitative methods are required to help neuropathologists in their clinical decision-making. Therefore, we propose a computerized image analysis method to validate anti-PTBP1 antibody for its potential use in diagnostic neuropathology. Images were obtained from standard neuropathological specimens stained with anti-PTBP1 antibody. First, the noise characteristics of the images were modeled and images are de-noised according to the noise model. Next, images are filtered with sigma-adaptive Gaussian filtering for normalization, and cell nuclei are detected and segmented with a k-means-based deterministic approach. Experiments on 29 data sets from 3 cases of brain tumor and reactive gliosis show statistically significant differences between the number of positively stained nuclei in images stained with and without anti-PTBP1 antibody. The experimental analysis of specimens from 3 different brain tumor groups and 1 reactive gliosis group indicates the feasibility of using anti-PTBP1 antibody in diagnostic neuropathology, and computerized image analysis provides a systematic and quantitative approach to explore feasibility.

  14. Image analysis of cell natural fluorescence: diagnostic applications in haematology

    NASA Astrophysics Data System (ADS)

    Monici, Monica; Agati, Giovanni; Mazzinghi, Piero; Fusi, Franco; Bernabei, Pietro A.; Landini, Stefano; Ferrini, Pierluigi R.; Pratesi, Riccardo

    1996-11-01

    Haematic cells, excited with radiation of suitable wavelength, give rise to a natural fluorescence (NF) emission. This paper investigates NF to develop new techniques for applications in both basic research and medical diagnostics. Results show that the cell populations examined exhibit peculiar emission bands. The intracellular fluorescence pattern reveals that flouresence is mainly located at cytoplasmic-level, thus related to the metabolic processes of the cells. The photophysical properties of cells appear different among the normal populations and between normal and leukaemic ones. Therefore the recognition of the various cellular elements, according to their fluorescence emission, is possible.

  15. Use of a sandwich technique to control image geometry in clinical studies comparing intraoral xeroradiographs and E-speed films

    SciTech Connect

    Ludlow, J.B.; Hill, R.A.; Hayes, C.J.

    1988-05-01

    A method of superimposing a film on a xeroradiographic (XR) cassette for simultaneous intraoral exposure is evaluated for use as an imaging technique in clinical studies comparing Ektaspeed film and XR images. Sandwich images were indistinguishable from those produced by conventional technique. Pilot studies were conducted with 104 patients who had symptomatic dental problems. No significant differences were found in diagnostic usefulness or image quality between XR and film radiographs when sign test analysis was used. The sandwich technique yielded film and XR images with duplicate image geometry while reducing patient exposures to one half of that used in conventional image comparison protocols.

  16. Diagnostic performance of computed tomography and magnetic resonance imaging for detecting peritoneal metastases: systematic review and meta-analysis.

    PubMed

    Laghi, Andrea; Bellini, Davide; Rengo, Marco; Accarpio, Fabio; Caruso, Damiano; Biacchi, Daniele; Di Giorgio, Angelo; Sammartino, Paolo

    2017-01-01

    Primary end point was to assess diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) in detecting peritoneal metastases (PM). Secondary end points were determining the diagnostic sensitivity and specificity of CT in detecting PM according to the peritoneal cancer index (PCI), investigating correlations between radiological and surgical PCI, and comparing diagnostic yield of CT versus positron emission tomography (PET)/CT. We searched MEDLINE, Cochrane Library, Embase and Web of Science databases. Analytic methods were based on PRISMA. Pooled estimates for sensitivity, specificity, positive and negative likelihood ratios were calculated using fixed and random effect models. I (2) was used to evaluate heterogeneity. Of the 529 articles initially identified, 22 were selected for inclusion (934 patients). Cumulative data for per patient CT diagnostic accuracy were sensitivity 83 % (95 % CI 79-86 %), specificity 86 % (95 % CI 82-89 %), pooled positive LR 4.37 (2.58-7.41), and pooled negative LR 0.20 (0.11-0.35). On a per region basis CT performed best in epigastrium and pelvis. Correlation analysis showed a high correlation between CT-PCI and surgical-PCI scores, ranging from 0.49 to 0.96. MRI and PET/CT achieved similar per patient diagnostic accuracy. CT should be the preferred diagnostic imaging modality for detecting peritoneal metastases because of the robustness of the data. MRI and PET/CT should be considered second choices, until more consistent information on their diagnostic yield in detecting PM are obtained.

  17. Children's Deviant Behavior in Primary Education: Comparing Physical Educator's Implicit Theory With Diagnostic Criteria.

    PubMed

    Efstratopoulou, Maria A; Janssen, Rianne; Simons, Johan

    2012-06-11

    Objective: Physical educators' implicit theory of children's deviant behavior in primary education was investigated and compared with diagnostic criteria. Method: A total of 60 physical education (PE) teachers reported deviant behaviors during lessons. Experts sorted these behaviors together with the official diagnostic criteria into categories based on perceived similarity in content. Results: Hierarchical cluster analysis on the derived similarity matrix among the behaviors suggested that PE teachers focus more on attention problems, disobedience, and aggressiveness when internalizing behaviors, such as anxiety and low energy, were less reported. Conclusion: PE teachers may be important and useful informants on children's behavior in school settings. (J. of Att. Dis. 2012; XX(X) 1-XX).

  18. Latest generation of flat detector CT as a peri-interventional diagnostic tool: a comparative study with multidetector CT.

    PubMed

    Leyhe, Johanna Rosemarie; Tsogkas, Ioannis; Hesse, Amélie Carolina; Behme, Daniel; Schregel, Katharina; Papageorgiou, Ismini; Liman, Jan; Knauth, Michael; Psychogios, Marios-Nikos

    2016-12-20

    Flat detector CT (FDCT) has been used as a peri-interventional diagnostic tool in numerous studies with mixed results regarding image quality and detection of intracranial lesions. We compared the diagnostic aspects of the latest generation FDCT with standard multidetector CT (MDCT). 102 patients were included in our retrospective study. All patients had undergone interventional procedures. FDCT was acquired peri-interventionally and compared with postinterventional MDCT regarding depiction of ventricular/subarachnoidal spaces, detection of intracranial hemorrhage, and delineation of ischemic lesions using an ordinal scale. Ischemic lesions were quantified with the Alberta Stroke Program Early CT Scale (ASPECTS) on both examinations. Two neuroradiologists with varying grades of experience and a medical student scored the anonymized images separately, blinded to the clinical history. The two methods were of equal diagnostic value regarding evaluation of the ventricular system and the subarachnoidal spaces. Subarachnoidal, intraventricular, and parenchymal hemorrhages were detected with a sensitivity of 95%, 97%, and 100% and specificity of 97%, 100%, and 99%, respectively, using FDCT. Gray-white differentiation was feasible in the majority of FDCT scans, and ischemic lesions were detected with a sensitivity of 71% on FDCT, compared with MDCT scans. The mean difference in ASPECTS values on FDCT and MDCT was 0.5 points (95% CI 0.12 to 0.88). The latest generation of FDCT is a reliable and accurate tool for the detection of intracranial hemorrhage. Gray-white differentiation is feasible in the supratentorial region. 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/.

  19. Advanced Imaging and Diagnostic Methods in the Assessment of Suspected Ischemic Heart Disease in Women.

    PubMed

    Joly, Joanna M; Bittner, Vera

    2016-09-01

    Although differences diminish with age, outcomes are overall worse for women compared to men who present with suspected acute coronary syndrome. The reasons for this discrepancy are multifactorial, including sex-related differences in atherosclerosis biology and fluid dynamics, as well as a premature conclusion by providers that chest pain must be noncardiac in the absence of obstructive coronary artery disease. In this review of existing literature, we explore the diverse differential diagnosis in this unique set of patients. Especially in women with persistent symptoms, absence of occlusive disease should prompt consideration for subangiographic plaque disruption, epicardial or microvascular endothelial dysfunction, transient neurohormonal imbalance predisposing to Takotsubo cardiomyopathy or spontaneous coronary artery dissection, underlying systemic inflammatory conditions, thromboembolic disease, myocarditis, and sequelae of congenital heart disease. As always, a thorough history and attentive physical exam will help guide further work-up, which in many cases may warrant noninvasive imaging, such as contrast-enhanced echocardiography, cardiac magnetic resonance imaging, or positron emission tomography, with their respective means of measuring myocardial perfusion and myocardial tissue pathology. Lastly, intracoronary imaging such as intravascular ultrasound and optical coherence tomography and invasive diagnostic methods such as coronary reactivity testing continue to add to our understanding that what appear to be atypical presentations of ischemic heart disease in women may in fact be typical presentations of pathologic cousin entities that remain incompletely defined.

  20. WE-A-BRF-01: Dual-Energy CT Imaging in Diagnostic Imaging and Radiation Therapy

    SciTech Connect

    Molloi, S; Li, B; Yin, F; Chen, H

    2014-06-15

    The quantification accuracy of dual-energy imaging is influenced by the fundamentals of x-ray physics, system geometry, data acquisition hardware/protocol, system calibration, and image processing technique. This symposium will provide updates on the following advanced application areas: Mammography. Volumetric breast density techniques based on standard mammograms require estimation of breast thickness, which is difficult to accurately measure. By comparison, calculation of breast density using dual energy mammography does not require measurement of breast thickness. Dual energy mammography has been implemented using both energy integrating flat panel detectors in conjunction with beam energy switching and energy resolved photon counting detectors. These techniques have been optimized using simulation studies and validated using physical phantoms and postmortem breasts. Chemical decomposition was used as the gold standard for volumetric breast density measurement in postmortem breasts. Breast density measurements have also been compared with results from four-category BI-RADS density rankings, standard image thresholding and Fuzzy k-mean clustering techniques. These studies indicate that dual energy mammography can be used to accurately measure volumetric breast density. Cardiovascular CT. The predicative accuracy of risk models for recurrent stroke and cardiac arrest depends heavily on accurate differentiation of thrombus or calcium from iodine in left atrial appendage or coronary arteries. The amount of energy separation is constrained by image noise; therefore, optimal kVp, beam filtration, and balanced flux are essential for the quantification accuracy of iodine and calcium. The basis materials are combined linearly to generate monochromatic energy images, where CT# accuracy and CNR are energy dependent. With optimal monochromatic energy, the mean iodine concentration for the thrombus, circulatory stasis, and control groups are significantly different. Risk

  1. Feasibility of poly(ethylene glycol) derivatives as diagnostic drug carriers for tumor imaging.

    PubMed

    Kanazaki, Kengo; Sano, Kohei; Makino, Akira; Yamauchi, Fumio; Takahashi, Atsushi; Homma, Tsutomu; Ono, Masahiro; Saji, Hideo

    2016-03-28

    Poly(ethylene glycol) (PEG) is an artificial but biocompatible hydrophilic polymer that has been widely used in clinical products. To evaluate the feasibility of using PEG derivative itself as a tumor imaging carrier via an enhanced permeability and retention (EPR) effect, we prepared indium-111-labeled PEG ((111)In-DTPA-PEG) and indocyanine green (ICG)-labeled PEG (ICG-PEG) with PEG molecular weights of 5-40kDa and investigated their in vivo biodistribution in colon26 tumor-bearing mice. Thereafter, single-photon emission computed tomography (SPECT) and photoacoustic (PA) imaging studies were performed. The in vivo biodistribution studies demonstrated increased tumor uptake and a prolongation of circulation half-life as the molecular weight of PEG increased. Although the observed differences in in vivo biodistribution were dependent on the labeling method ((111)In or ICG), the tumor-to-normal tissue ratios were comparable. Because PEG-based probes with a molecular weight of 20kDa (PEG20) showed a preferable biodistribution (highest accumulation among tissues excised and relatively high tumor-to-blood ratios), an imaging study using (111)In-DTPA-PEG20 and ICG-PEG20 was performed. Colon26 tumors inoculated in the right shoulder were clearly visualized by SPECT 24h after administration. Furthermore, PA imaging using ICG-PEG20 also detected tumor regions, and the detected PA signals increased in proportion with the injected dose. These results suggest that PEG derivatives (20kDa) serve as robust diagnostic drug carriers for tumor imaging. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Mobile teledermatology for skin tumour screening: diagnostic accuracy of clinical and dermoscopic image tele-evaluation using cellular phones.

    PubMed

    Kroemer, S; Frühauf, J; Campbell, T M; Massone, C; Schwantzer, G; Soyer, H P; Hofmann-Wellenhof, R

    2011-05-01

    The ability to diagnose malignant skin tumours accurately and to distinguish them from benign lesions is vital in ensuring appropriate patient management. Little is known about the effects of mobile teledermatology services on diagnostic accuracy and their appropriateness for skin tumour surveillance. To evaluate the diagnostic accuracy of clinical and dermoscopic image tele-evaluation for mobile skin tumour screening. Over a 3-month period up to three clinical and dermoscopic images were obtained of 113 skin tumours from 88 patients using a mobile phone camera. Dermoscopic images were taken with a dermatoscope applied to the camera lens. Clinical and dermoscopic images of each lesion together with clinical information were separately teletransmitted for decision-making. Results were compared with those obtained by face-to-face examination and histopathology as the gold standard. A total of 322 clinical and 278 dermoscopic images were acquired; two (1%) clinical and 18 (6%) dermoscopic pictures were inadequate for decision-making. After excluding inadequate images, the majority of which were dermoscopic pictures, only 104 of the 113 skin tumours from 80 of 88 patients could be tele-evaluated. Among these 104 lesions, 25 (24%) benign nonmelanocytic, 15 (14%) benign melanocytic, 58 (56%) malignant nonmelanocytic and six (6%) malignant melanocytic lesions were identified. Clinical and dermoscopic tele-evaluations demonstrated strong concordance with the gold standard (κ = 0·84 for each) and similar high sensitivity and specificity for all diagnostic categories. With regard to the detailed diagnoses, clinical image tele-evaluation was superior to teledermoscopy resulting in 16 vs. 22 discordant cases. Clinical image tele-evaluation might be the method of choice for mobile tumour screening. © 2011 The Authors. BJD © 2011 British Association of Dermatologists.

  3. Fahr disease: use of susceptibility-weighted imaging for diagnostic dilemma with magnetic resonance imaging

    PubMed Central

    Solak, Aynur; Genc, Berhan; Kulu, Ugur

    2015-01-01

    Fahr disease (FD) is a well-defined rare neurodegenerative disease that is characterized by idiopathic bilateral symmetric extensive striopallidodentate calcifications. The patients may present with diverse manifestations, most commonly movement disorder, cognitive impairment, and ataxia. Computed tomography (CT) is considered to be critical for accurate diagnosis because it is difficult to reliably identify calcifications by routine magnetic resonance imaging (MRI). Susceptibility-weighted imaging (SWI) is a relatively new 3D gradient-echo (GE) MR sequence with special phase and magnitude processing. SWI phase images can recognize calcifications definitively with higher sensitivity compared to other MRI sequences. In this article, we present two cases of FD with different manifestations and neuroimaging in different age groups and genders, which were diagnosed by SWI and confirmed with CT, and we discuss the contribution of SWI in the diagnosis of FD. In conclusion, we suggest integrating SWI with MRI protocol to identify calcifications in suspicion of neurodegenerative disorders. PMID:26435928

  4. Fahr disease: use of susceptibility-weighted imaging for diagnostic dilemma with magnetic resonance imaging.

    PubMed

    Sahin, Neslin; Solak, Aynur; Genc, Berhan; Kulu, Ugur

    2015-08-01

    Fahr disease (FD) is a well-defined rare neurodegenerative disease that is characterized by idiopathic bilateral symmetric extensive striopallidodentate calcifications. The patients may present with diverse manifestations, most commonly movement disorder, cognitive impairment, and ataxia. Computed tomography (CT) is considered to be critical for accurate diagnosis because it is difficult to reliably identify calcifications by routine magnetic resonance imaging (MRI). Susceptibility-weighted imaging (SWI) is a relatively new 3D gradient-echo (GE) MR sequence with special phase and magnitude processing. SWI phase images can recognize calcifications definitively with higher sensitivity compared to other MRI sequences. In this article, we present two cases of FD with different manifestations and neuroimaging in different age groups and genders, which were diagnosed by SWI and confirmed with CT, and we discuss the contribution of SWI in the diagnosis of FD. In conclusion, we suggest integrating SWI with MRI protocol to identify calcifications in suspicion of neurodegenerative disorders.

  5. Imaging in axial spondyloarthritis: diagnostic problems and pitfalls.

    PubMed

    Baraliakos, Xenofon; Hermann, Kay-Geert A; Braun, Jürgen

    2012-08-01

    Magnetic Structural changes in axial Spondyloarthritis (axSpA) are best identified by conventional radiographs, while magnetic resonance imaging (MRI) is considered the gold standard for assessment of inflammatory changes. Imaging of the axial skeleton is crucial for the diagnosis but also for classification to non-radiographic axSpA according to the 2009 ASAS classification criteria. Despite the existing definitions for a positive MRI for the sacroiliac joints and the spine, these predefined lesions can also be seen in other conditions, representing pitfalls and false-positive conclusions in patients with similar clinical symptoms who do not have SpA. Diagnosis of SpA should result from the combination of clinical, laboratory and imaging findings.

  6. The Diagnostic Radiological Utilization Of 3-D Display Images

    NASA Astrophysics Data System (ADS)

    Cook, Larry T.; Dwyer, Samuel J.; Preston, David F.; Batnitzky, Solomon; Lee, Kyo R.

    1984-10-01

    In the practice of radiology, computer graphics systems have become an integral part of the use of computed tomography (CT), nuclear medicine (NM), magnetic resonance imaging (MRI), digital subtraction angiography (DSA) and ultrasound. Gray scale computerized display systems are used to display, manipulate, and record scans in all of these modalities. As the use of these imaging systems has spread, various applications involving digital image manipulation have also been widely accepted in the radiological community. We discuss one of the more esoteric of such applications, namely, the reconstruction of 3-D structures from plane section data, such as CT scans. Our technique is based on the acquisition of contour data from successive sections, the definition of the implicit surface defined by such contours, and the application of the appropriate computer graphics hardware and software to present reasonably pleasing pictures.

  7. Diagnostic imaging of abdominal fluid collections and abscesses.

    PubMed

    Baker, M E; Blinder, R A; Rice, R P

    1986-01-01

    With today's advanced technology, the clinician and radiologist have a number of techniques with which to evaluate the abdomen for fluid collections and/or abscesses. Three points are clear from the plethora of literature concerning this subject: the need to individualize the clinical and imaging approach to each patient suspected of an abnormal fluid collection or abscess, the need to individualize the imaging procedure based upon what is done best at the institution, and the need for percutaneous aspiration of all fluid collections for diagnosis. No single imaging test is totally sensitive or specific for the detection of an infected fluid collection. Overall, CT probably does provide the most accurate means to detect an intra-abdominal abscess. Because of this, and because it is less operator dependent than ultrasound, CT is used most often as the procedure of choice at our institution.

  8. [Diagnostic approach to cardiopathies by means of magnetic resonance imaging].

    PubMed

    Gutiérrez Zamora, Agustín

    2005-01-01

    Cardiomyopathies encompass a broad spectrum of heart pathologies having a basic principle, the intrinsic injury of the myocardial fiber. By definition, cardiomyopathies could be primary (dilated cardiomyopathy), or can be a consequence of another cardiovascular illness (high blood pressure), or of genetic anomalies, such as hypertrophic cardiomyopathy, or due to alterations in myocytes due to fibrolipidic material as occurs in right ventricle arrhythmogenic dysplasia. Currently, magnetic resonance imaging is the best method to approach the diagnosis of these pathologies. Magnetic resonance imaging has allowed us to study histological sections through adequate sequences and using gadolinium as contrast agent. We present herein a simple way to approach the diagnosis of cardiomyopathies by means of magnetic resonance imaging methods.

  9. The next generation of electron cyclotron emission imaging diagnostics (invited).

    PubMed

    Zhang, P; Domier, C W; Liang, T; Kong, X; Tobias, B; Shen, Z; Luhmann, N C; Park, H; Classen, I G J; van de Pol, M J; Donné, A J H; Jaspers, R

    2008-10-01

    A 128 channel two-dimensional electron cyclotron emission imaging system collects time-resolved 16x8 images of T(e) profiles and fluctuations on the TEXTOR tokamak. Electron cyclotron emission imaging (ECEI) is undergoing significant changes which promise to revolutionize and extend its capabilities far beyond what has been achieved to date. These include the development of a minilens array configuration with increased sensitivity antennas, a new local oscillator pumping scheme, enhanced electron cyclotron resonance heating shielding, and a highly flexible optical design with vertical zoom capability. Horizontal zoom and spot size (rf bandwidth) capabilities are also being developed with new ECEI electronics. An interface module is under development to remotely control all key features of the new ECEI instrument, many of which can be changed during a plasma discharge for maximum flexibility.

  10. The next generation of electron cyclotron emission imaging diagnostics (invited)

    SciTech Connect

    Zhang, P.; Domier, C. W.; Liang, T.; Kong, X.; Tobias, B.; Shen, Z.; Luhmann, N. C. Jr.; Park, H.; Classen, I. G. J.; Pol, M. J. van de; Donne, A. J. H.; Jaspers, R.

    2008-10-15

    A 128 channel two-dimensional electron cyclotron emission imaging system collects time-resolved 16x8 images of T{sub e} profiles and fluctuations on the TEXTOR tokamak. Electron cyclotron emission imaging (ECEI) is undergoing significant changes which promise to revolutionize and extend its capabilities far beyond what has been achieved to date. These include the development of a minilens array configuration with increased sensitivity antennas, a new local oscillator pumping scheme, enhanced electron cyclotron resonance heating shielding, and a highly flexible optical design with vertical zoom capability. Horizontal zoom and spot size (rf bandwidth) capabilities are also being developed with new ECEI electronics. An interface module is under development to remotely control all key features of the new ECEI instrument, many of which can be changed during a plasma discharge for maximum flexibility.

  11. New real-time strain imaging concepts using diagnostic ultrasound.

    PubMed

    Pesavento, A; Lorenz, A; Siebers, S; Ermert, H

    2000-06-01

    Two real-time strain imaging concepts and systems are presented. Both systems are based on a conventional ultrasound scanner that is connected to a PC with an A/D converter card for real-time data acquisition of rf data. Differential strain between successively acquired rf frames are estimated using phase root seeking. The first concept uses a special real-time implementation of manual elastography. In the second concept, denoted 'vibrography', the static compression is replaced by low-frequency axial vibration of the probe, still operating in quasistatic acquisition mode. The properties of both concepts are discussed with regard to noise and motion artefacts, and it is shown, using simulations and phantom experiments, that both imaging concepts yield the same kind of strain images. Vibrography has the advantage that no manual compression has to be applied, total compression can be very low and some motion artefacts are better suppressed.

  12. New real-time strain imaging concepts using diagnostic ultrasound

    NASA Astrophysics Data System (ADS)

    Pesavento, A.; Lorenz, A.; Siebers, S.; Ermert, H.

    2000-06-01

    Two real-time strain imaging concepts and systems are presented. Both systems are based on a conventional ultrasound scanner that is connected to a PC with an A/D converter card for real-time data acquisition of rf data. Differential strain between successively acquired rf frames are estimated using phase root seeking. The first concept uses a special real-time implementation of manual elastography. In the second concept, denoted `vibrography', the static compression is replaced by low-frequency axial vibration of the probe, still operating in quasistatic acquisition mode. The properties of both concepts are discussed with regard to noise and motion artefacts, and it is shown, using simulations and phantom experiments, that both imaging concepts yield the same kind of strain images. Vibrography has the advantage that no manual compression has to be applied, total compression can be very low and some motion artefacts are better suppressed.

  13. Ordering Diagnostic Imaging: A Survey of Ontario Physiotherapists' Opinions on an Expanded Scope of Practice

    PubMed Central

    Chong, Jodie Ng Fuk; De Luca, Krista; Goldan, Sana; Imam, Abdullah; Li, Boris; Zabjek, Karl; Chu, Anna

    2015-01-01

    ABSTRACT Purpose: To explore Ontario physiotherapists' opinions on their ability to order diagnostic imaging (DI). Methods: An online questionnaire was sent to all registered members of the College of Physiotherapists of Ontario. Descriptive statistics were calculated using response frequencies. Practice characteristics were compared using χ2 tests and Wilcoxon rank–sum tests. Results: Of 1,574 respondents (21% response rate), 42% practised in orthopaedics and 53% in the public sector. Most physiotherapists were interested in ordering DI (72% MRI/diagnostic ultrasound, 78% X-rays/computed tomography scans). Respondents with an orthopaedic caseload of 50% or more (p<0.001) and those in the private sector (p<0.001) were more interested in ordering DI. Respondents preferred a DI course that combined face-to-face and Web-based components and one that was specific to their area of practice. Most respondents perceived minimal barriers to the uptake of ordering DI, and most agreed that support from other health care professionals would facilitate uptake. Conclusion: The majority of Ontario physiotherapists are interested in ordering DI. For successful implementation of a health care change, such as physiotherapists' ability to order DI, educational needs and barriers to and facilitators of the uptake of the authorized activity should be considered. PMID:25931666

  14. Ordering diagnostic imaging: a survey of ontario physiotherapists' opinions on an expanded scope of practice.

    PubMed

    Chong, Jodie Ng Fuk; De Luca, Krista; Goldan, Sana; Imam, Abdullah; Li, Boris; Zabjek, Karl; Chu, Anna; Yeung, Euson

    2015-01-01

    To explore Ontario physiotherapists' opinions on their ability to order diagnostic imaging (DI). An online questionnaire was sent to all registered members of the College of Physiotherapists of Ontario. Descriptive statistics were calculated using response frequencies. Practice characteristics were compared using χ(2) tests and Wilcoxon rank-sum tests. Of 1,574 respondents (21% response rate), 42% practised in orthopaedics and 53% in the public sector. Most physiotherapists were interested in ordering DI (72% MRI/diagnostic ultrasound, 78% X-rays/computed tomography scans). Respondents with an orthopaedic caseload of 50% or more (p<0.001) and those in the private sector (p<0.001) were more interested in ordering DI. Respondents preferred a DI course that combined face-to-face and Web-based components and one that was specific to their area of practice. Most respondents perceived minimal barriers to the uptake of ordering DI, and most agreed that support from other health care professionals would facilitate uptake. The majority of Ontario physiotherapists are interested in ordering DI. For successful implementation of a health care change, such as physiotherapists' ability to order DI, educational needs and barriers to and facilitators of the uptake of the authorized activity should be considered.

  15. Diagnostic accuracy of MR imaging in tuberculous spondylitis.

    PubMed

    Danchaivijitr, Nasuda; Temram, Siriwan; Thepmongkhol, Kullathorn; Chiewvit, Pipat

    2007-08-01

    To systemically evaluate MR imaging features of tuberculous spondylitis and to find features that may help differentiating tuberculosis from other spinal diseases. Retrospective review of 65 MR imaging of two groups of patients between January 2002 and December 2005. Thirty-one patients were diagnosed as tuberculosis spondylitis and the rest were a randomly selected group of 34 patients with other spinal diseases. All images were reviewed by two neuroradiologists blinded to clinical data. Sensitivity and specificity of each MR imaging features were calculated. Three most useful MR imaging features with high sensitivity and specificity (> 80%) were endplate disruption (100%, 81.4%), paravertebral soft tissue (96.8%, 85.3%), and high signal intensity of intervertebral disc on T2W (80.6%, 82.4%). High sensitivity but low specificity signs in MRI included bone marrow edema (90.3%, 76.5%), bone marrow enhancement (100%, 42.5%), posterior element involvement (93.5%, 76.5%), canal stenosis (87.1%, 26.5%), and spinal cord or nerve root compression (80.6%, 38.2%). Low sensitivity but high specificity features in MRI were intervertebral disc enhancement (63.3%, 84.2%), vertebral collapse (58.1%, 85.3%), and kyphosis deformity (67.7%, 82.4%). Overall, the sensitivity and specificity of MRI for spinal tuberculosis were 100% and 88.2% respectively. The authors presented three good to excellent sensitivity and specificity MR imaging features for spinal tuberculosis, end plate disruption, paravertebral soft tissue formation, and high signal of intervertebral disc on T2W. In contrast to a previous study, most of the presented cases still presented with classic radiological pictures of "two vertebral disease with the destruction of the intervertebral disc". Only a small portion of the patients revealed sparing intervening disc or isolated single vertebral body involvement, which possibly reflected the early stages of the disease process.

  16. Clinics in diagnostic imaging (162). Meckel’s diverticulum

    PubMed Central

    Singh, Dinesh R; Pulickal, Geoiphy G; Lo, Zhiwen J; Peh, Wilfred CG

    2015-01-01

    A 28-year-old Chinese man presented with acute bleeding per rectum. Computed tomography showed a posterior outpouching arising from the distal ileum. The outpouching had hyperaemic walls, but no active contrast extravasation was detected. Technetium-99m pertechnetate scintigraphy showed focal areas of abnormal uptake in the right side of the pelvis, superior and posterior to the urinary bladder. These areas of uptake appeared simultaneously with the gastric uptake and demonstrated gradual increase in intensity on subsequent images. The diagnosis of Meckel’s diverticulum was confirmed on surgery and the lesion was resected. The clinical and imaging features of Meckel’s diverticulum are discussed. PMID:26451056

  17. Dropped gallstones: spectrum of imaging findings, complications and diagnostic pitfalls.

    PubMed

    Nayak, L; Menias, C O; Gayer, G

    2013-08-01

    Spillage of gallstones into the abdominal cavity, referred to as "dropped gallstones" (DGs), occurs commonly during laparoscopic cholecystectomy. The majority of these spilled stones remain clinically silent; however, if uncomplicated DGs are not correctly identified on subsequent imaging, they may mimic peritoneal implants and cause unduly concern. A small percentage of DGs cause complications, including abscess and fistula formation. Recognising the DG within the abscess is critical for definitive treatment. This pictorial review illustrates the imaging appearances and complications of DGs on CT, MRI and ultrasound and emphasises pitfalls in diagnosis.

  18. Diagnostic precision of PET imaging and functional MRI in disorders of consciousness: a clinical validation study.

    PubMed

    Stender, Johan; Gosseries, Olivia; Bruno, Marie-Aurélie; Charland-Verville, Vanessa; Vanhaudenhuyse, Audrey; Demertzi, Athena; Chatelle, Camille; Thonnard, Marie; Thibaut, Aurore; Heine, Lizette; Soddu, Andrea; Boly, Mélanie; Schnakers, Caroline; Gjedde, Albert; Laureys, Steven

    2014-08-09

    Bedside clinical examinations can have high rates of misdiagnosis of unresponsive wakefulness syndrome (vegetative state) or minimally conscious state. The diagnostic and prognostic usefulness of neuroimaging-based approaches has not been established in a clinical setting. We did a validation study of two neuroimaging-based diagnostic methods: PET imaging and functional MRI (fMRI). For this clinical validation study, we included patients referred to the University Hospital of Liège, Belgium, between January, 2008, and June, 2012, who were diagnosed by our unit with unresponsive wakefulness syndrome, locked-in syndrome, or minimally conscious state with traumatic or non-traumatic causes. We did repeated standardised clinical assessments with the Coma Recovery Scale-Revised (CRS-R), cerebral (18)F-fluorodeoxyglucose (FDG) PET, and fMRI during mental activation tasks. We calculated the diagnostic accuracy of both imaging methods with CRS-R diagnosis as reference. We assessed outcome after 12 months with the Glasgow Outcome Scale-Extended. We included 41 patients with unresponsive wakefulness syndrome, four with locked-in syndrome, and 81 in a minimally conscious state (48=traumatic, 78=non-traumatic; 110=chronic, 16=subacute). (18)F-FDG PET had high sensitivity for identification of patients in a minimally conscious state (93%, 95% CI 85-98) and high congruence (85%, 77-90) with behavioural CRS-R scores. The active fMRI method was less sensitive at diagnosis of a minimally conscious state (45%, 30-61) and had lower overall congruence with behavioural scores (63%, 51-73) than PET imaging. (18)F-FDG PET correctly predicted outcome in 75 of 102 patients (74%, 64-81), and fMRI in 36 of 65 patients (56%, 43-67). 13 of 41 (32%) of the behaviourally unresponsive patients (ie, diagnosed as unresponsive with CRS-R) showed brain activity compatible with (minimal) consciousness (ie, activity associated with consciousness, but diminished compared with fully conscious individuals

  19. The method of polarization selection of laser images in diagnostics of polycrystalline structure of human bile layers

    NASA Astrophysics Data System (ADS)

    Ivashchuk, I. O.; Marchuk, Yu. F.; Fediv, O. I.; Andriychuk, D. R.

    2011-09-01

    In this paper the possibility of polarization correlometry complex distributions of azimuth and ellipticity of laser images polarization of layers of human bile. Were found new approach of comparative analysis of polarization of different points in the far field. The principles of optical model of human bile polycrystalline structure are described. The results of investigating the interrelation between the values of statistical, correlation and fractal parameters are presented. They characterize the coordinate distributions of mutual polarization degree of the points of laser images of bile smears of cholelithiasis patients in combination with other pathologies. The diagnostic criteria of the cholelithiasis nascency and its severity degree differentiation are determined.

  20. The method of polarization selection of laser images in diagnostics of polycrystalline structure of human bile layers

    NASA Astrophysics Data System (ADS)

    Ivashchuk, I. O.; Marchuk, Yu. F.; Fediv, O. I.; Andriychuk, D. R.

    2012-01-01

    In this paper the possibility of polarization correlometry complex distributions of azimuth and ellipticity of laser images polarization of layers of human bile. Were found new approach of comparative analysis of polarization of different points in the far field. The principles of optical model of human bile polycrystalline structure are described. The results of investigating the interrelation between the values of statistical, correlation and fractal parameters are presented. They characterize the coordinate distributions of mutual polarization degree of the points of laser images of bile smears of cholelithiasis patients in combination with other pathologies. The diagnostic criteria of the cholelithiasis nascency and its severity degree differentiation are determined.

  1. Volume perfusion CT imaging of cerebral vasospasm: diagnostic performance of different perfusion maps.

    PubMed

    Othman, Ahmed E; Afat, Saif; Nikoubashman, Omid; Müller, Marguerite; Schubert, Gerrit Alexander; Bier, Georg; Brockmann, Marc A; Wiesmann, Martin; Brockmann, Carolin

    2016-08-01

    In this study, we aimed to evaluate the diagnostic performance of different volume perfusion CT (VPCT) maps regarding the detection of cerebral vasospasm compared to angiographic findings. Forty-one datasets of 26 patients (57.5 ± 10.8 years, 18 F) with subarachnoid hemorrhage and suspected cerebral vasospasm, who underwent VPCT and angiography within 6 h, were included. Two neuroradiologists independently evaluated the presence and severity of vasospasm on perfusion maps on a 3-point Likert scale (0-no vasospasm, 1-vasospasm affecting <50 %, 2-vasospasm affecting >50 % of vascular territory). A third neuroradiologist independently assessed angiography for the presence and severity of vasospasm on a 3-point Likert scale (0-no vasospasm, 1-vasospasm affecting < 50 %, 2-vasospasm affecting > 50 % of vessel diameter). Perfusion maps of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to drain (TTD) were evaluated regarding diagnostic accuracy for cerebral vasospasm with angiography as reference standard. Correlation analysis of vasospasm severity on perfusion maps and angiographic images was performed. Furthermore, inter-reader agreement was assessed regarding findings on perfusion maps. Diagnostic accuracy for TTD and MTT was significantly higher than for all other perfusion maps (TTD, AUC = 0.832; MTT, AUC = 0.791; p < 0.001). TTD revealed higher sensitivity than MTT (p = 0.007). The severity of vasospasm on TTD maps showed significantly higher correlation levels with angiography than all other perfusion maps (p ≤ 0.048). Inter-reader agreement was (almost) perfect for all perfusion maps (kappa ≥ 0.927). The results of this study indicate that TTD maps have the highest sensitivity for the detection of cerebral vasospasm and highest correlation with angiography regarding the severity of vasospasm.

  2. Multi-method analysis of MRI images in early diagnostics of Alzheimer's disease.

    PubMed

    Wolz, Robin; Julkunen, Valtteri; Koikkalainen, Juha; Niskanen, Eini; Zhang, Dong Ping; Rueckert, Daniel; Soininen, Hilkka; Lötjönen, Jyrki

    2011-01-01

    The role of structural brain magnetic resonance imaging (MRI) is becoming more and more emphasized in the early diagnostics of Alzheimer's disease (AD). This study aimed to assess the improvement in classification accuracy that can be achieved by combining features from different structural MRI analysis techniques. Automatically estimated MR features used are hippocampal volume, tensor-based morphometry, cortical thickness and a novel technique based on manifold learning. Baseline MRIs acquired from all 834 subjects (231 healthy controls (HC), 238 stable mild cognitive impairment (S-MCI), 167 MCI to AD progressors (P-MCI), 198 AD) from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database were used for evaluation. We compared the classification accuracy achieved with linear discriminant analysis (LDA) and support vector machines (SVM). The best results achieved with individual features are 90% sensitivity and 84% specificity (HC/AD classification), 64%/66% (S-MCI/P-MCI) and 82%/76% (HC/P-MCI) with the LDA classifier. The combination of all features improved these results to 93% sensitivity and 85% specificity (HC/AD), 67%/69% (S-MCI/P-MCI) and 86%/82% (HC/P-MCI). Compared with previously published results in the ADNI database using individual MR-based features, the presented results show that a comprehensive analysis of MRI images combining multiple features improves classification accuracy and predictive power in detecting early AD. The most stable and reliable classification was achieved when combining all available features.

  3. Applications of imaging flow cytometry in the diagnostic assessment of acute leukaemia.

    PubMed

    Grimwade, Lizz F; Fuller, Kathryn A; Erber, Wendy N

    2017-01-01

    Automated imaging flow cytometry integrates flow cytometry with digital microscopy to produce high-resolution digital imaging with quantitative analysis. This enables cell identification based on morphology (cell size, shape), antigen expression, quantification of fluorescence signal intensity and localisation of detected signals (i.e. surface, cytoplasm, nuclear). We describe applications of imaging flow cytometry for the diagnostic assessment of acute leukaemia. These bone marrow malignancies are traditionally diagnosed and classified by cell morphology, phenotype and cytogenetic abnormalities. Traditionally morphology is assessed by light microscopy, phenotyping by conventional flow cytometry and genetics by karyotype and fluorescence in situ hybridisation (FISH) on interphase nuclei/metaphase spreads of cells on slides. Imaging flow cytometry adds a new dimension to the diagnostic assessment of these neoplasms. We describe three specific applications: From this we conclude that imaging flow cytometry offers benefits over conventional diagnostic methods. Specifically the ability to visualise the cells of interest, the pattern and localisation of expressed antigens and assess cytogenetic abnormalities in one integrated automated high-throughput test. Imaging flow cytometry presents a new paradigm for the diagnostic assessment of leukaemia.

  4. Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD): Development of Image Analysis Criteria and Examiner Reliability for Image Analysis

    PubMed Central

    Ahmad, Mansur; Hollender, Lars; Odont; Anderson, Quentin; Kartha, Krishnan; Ohrbach, Richard K.; Truelove, Edmond L.; John, Mike T.; Schiffman, Eric L.

    2011-01-01

    Introduction As a part of a multi-site RDC/TMD Validation Project, comprehensive TMJ diagnostic criteria were developed for image analysis using panoramic radiography, magnetic resonance imaging (MRI), and computed tomography (CT). Methods Inter-examiner reliability was estimated using the kappa (k) statistic, and agreement between rater pairs was characterized by overall, positive, and negative percent agreement. CT was the reference standard for assessing validity of other imaging modalities for detecting osteoarthritis (OA). Results For the radiological diagnosis of OA, reliability of the three examiners was poor for panoramic radiography (k = 0.16), fair for MRI (k = 0.46), and close to the threshold for excellent for CT (k = 0.71). Using MRI, reliability was excellent for diagnosing disc displacements (DD) with reduction (k = 0.78) and for DD without reduction (k = 0.94), and was good for effusion (k = 0.64). Overall percent agreement for pair-wise ratings was ≥ 82% for all conditions. Positive percent agreement for diagnosing OA was 19% for panoramic radiography, 59% for MRI, and 84% for CT. Using MRI, positive percent agreement for diagnoses of any DD was 95% and for effusion was 81%. Negative percent agreement was ≥ 88% for all conditions. Compared to CT, panoramic radiography and MRI had poor to marginal sensitivity, respectively, but excellent specificity, in detecting OA. Conclusion Comprehensive image analysis criteria for RDC/TMD Validation Project were developed, which can reliably be employed for assessing OA using CT, and for disc position and effusion using MRI. PMID:19464658

  5. Diagnostic imaging of the locomotor system- historical reviev.

    PubMed

    Swiatkowski, Jan; Białoszewski, Dariusz; Urbanik, Andrzej

    2002-10-30

    This work discusses the stages in the development of techniques used for imaging the locomotor apparatus. Attention is also drawn to the fact that from the very beginning of the "Roentgen era" Polish scientists were among its leading advocates and promoters.

  6. Clinics in diagnostic imaging (29). Thalassaemia major with iron overload.

    PubMed

    Griffith, J F; King, A D; Chan, Y L

    1997-09-01

    A 5-year-old girl presented with lethargy, anaemia and facial distortion. Both parents had beta-thalassaemia minor. Radiographs confirmed the characteristic features of thalassaemia major. A treatment regime comprising regular blood transfusions was commenced. The basis of the radiographic changes and the current role of magnetic resonance imaging, particularly with respect to assessing iron overload, are emphasized.

  7. MULTISPECTRAL DIAGNOSTIC IMAGING OF THE IRIS IN PIGMENT DISPERSION SYNDROME

    PubMed Central

    Roberts, Daniel K.; Lukic, Ana; Yang, Yongyi; Wilensky, Jacob T.; Wernick, Miles N.

    2011-01-01

    Purpose To determine if wavelength selection with near infrared (NIR) iris imaging may enhance iris transillumination defects (ITDs) in pigment dispersion syndrome. Methods An experimental apparatus was used to acquire iris images in 6 African-American (AA) and 6 White patients with pigment dispersion syndrome. Light emitting diode (LED) probes of 6 different spectral bands (700 to 950 nm) were used to project light into patients' eyes. Iris patterns were photographed, ITD regions of interest were outlined, and region of interest contrasts were calculated for each spectral band. Results Contrasts varied as a function of wavelength (P<0.0001) for both groups, but tended to be highest in the 700 to 800 nm range. Contrasts were higher in Whites than AAs at 700 nm but the opposite was found at 810 nm (P<0.001). Conclusions Optimized NIR iris imaging may be wavelength dependent. Ideal wavelength to image ITDs in more pigmented eyes may be slightly longer than for less pigmented eyes. PMID:21423031

  8. Committee Opinion No. 723: Guidelines for Diagnostic Imaging During Pregnancy and Lactation.

    PubMed

    2017-10-01

    Imaging studies are important adjuncts in the diagnostic evaluation of acute and chronic conditions. However, confusion about the safety of these modalities for pregnant and lactating women and their infants often results in unnecessary avoidance of useful diagnostic tests or the unnecessary interruption of breastfeeding. Ultrasonography and magnetic resonance imaging are not associated with risk and are the imaging techniques of choice for the pregnant patient, but they should be used prudently and only when use is expected to answer a relevant clinical question or otherwise provide medical benefit to the patient. With few exceptions, radiation exposure through radiography, computed tomography scan, or nuclear medicine imaging techniques is at a dose much lower than the exposure associated with fetal harm. If these techniques are necessary in addition to ultrasonography or magnetic resonance imaging or are more readily available for the diagnosis in question, they should not be withheld from a pregnant patient. Breastfeeding should not be interrupted after gadolinium administration.

  9. Committee Opinion No. 723 Summary: Guidelines for Diagnostic Imaging During Pregnancy and Lactation.

    PubMed

    2017-10-01

    Imaging studies are important adjuncts in the diagnostic evaluation of acute and chronic conditions. However, confusion about the safety of these modalities for pregnant and lactating women and their infants often results in unnecessary avoidance of useful diagnostic tests or the unnecessary interruption of breastfeeding. Ultrasonography and magnetic resonance imaging are not associated with risk and are the imaging techniques of choice for the pregnant patient, but they should be used prudently and only when use is expected to answer a relevant clinical question or otherwise provide medical benefit to the patient. With few exceptions, radiation exposure through radiography, computed tomography scan, or nuclear medicine imaging techniques is at a dose much lower than the exposure associated with fetal harm. If these techniques are necessary in addition to ultrasonography or magnetic resonance imaging or are more readily available for the diagnosis in question, they should not be withheld from a pregnant patient. Breastfeeding should not be interrupted after gadolinium administration.

  10. Effect of JPEG compression on the diagnostic accuracy of periapical images in the detection of root fracture.

    PubMed

    Noujeim, Marcel; Geha, Hassem; Shintaku, Werner; Bechara, Boulos; Kashi, Khosrow Aroni

    2012-06-01

    The ability of a periapical radiograph to exhibit the fracture depends on many factors including, but not limited to, the resolution of the image. The quality can be reduced by the image compression. The purpose of this study is to evaluate the effect of Joint Photographic Experts Group (JPEG) compressions on the diagnostic capability of periapical images in the detection of root fractures. Ten dry human mandibles containing 151 teeth were used in this study. Mandibles were radiographed with direct digital imaging sensor using the paralleling technique. Four observers detected root fracture on the images saved in one uncompressed and two compressed formats. Receiver operating characteristic (ROC) and anova analyses were performed to compare the performance of the three different systems and evaluate the effect of the compression on the accuracy of root fracture detection. Results did not show any statistically significant difference between the original, large images presented in tagged image file format (TIFF) and the two compressed images (JPEG medium file and JPEG small file images) in the detection of root fractures. The intra-rater comparison showed a significant consistency in the detection of the fracture. The compression reduced the file size considerably (from 1.77 MB to 453 and 95 Kb), but it did not affect the accuracy of root fracture detection. The file size reduction, on the other hand, is very beneficial for image electronic storage and mainly in teleradiology. © 2011 John Wiley & Sons A/S.

  11. Polyethersulfone improves isothermal nucleic acid amplification compared to current paper-based diagnostics

    PubMed Central

    Linnes, J. C.; Rodriguez, N. M.; Liu, L.

    2016-01-01

    Devices based on rapid, paper-based, isothermal nucleic acid amplification techniques have recently emerged with the potential to fill a growing need for highly sensitive point-of-care diagnostics throughout the world. As this field develops, such devices will require optimized materials that promote amplification and sample preparation. Herein, we systematically investigated isothermal nucleic acid amplification in materials currently used in rapid diagnostics (cellulose paper, glass fiber, and nitrocellulose) and two additional porous membranes with upstream sample preparation capabilities (polyethersulfone and polycarbonate). We compared amplification efficiency from four separate DNA and RNA targets (Bordetella pertussis, Chlamydia trachomatis, Neisseria gonorrhoeae, and Influenza A H1N1) within these materials using two different isothermal amplification schemes, helicase dependent amplification (tHDA) and loop-mediated isothermal amplification (LAMP), and traditional PCR. We found that the current paper-based diagnostic membranes inhibited nucleic acid amplification when compared to membrane-free controls; however, polyethersulfone allowed for efficient amplification in both LAMP and tHDA reactions. Further, observing the performance of traditional PCR amplification within these membranes was not predicative of their effects on in situ LAMP and tHDA. Polyethersulfone is a new material for paper-based nucleic acid amplification, yet provides an optimal support for rapid molecular diagnostics for point-of-care applications. PMID:26906904

  12. Polyethersulfone improves isothermal nucleic acid amplification compared to current paper-based diagnostics.

    PubMed

    Linnes, J C; Rodriguez, N M; Liu, L; Klapperich, C M

    2016-04-01

    Devices based on rapid, paper-based, isothermal nucleic acid amplification techniques have recently emerged with the potential to fill a growing need for highly sensitive point-of-care diagnostics throughout the world. As this field develops, such devices will require optimized materials that promote amplification and sample preparation. Herein, we systematically investigated isothermal nucleic acid amplification in materials currently used in rapid diagnostics (cellulose paper, glass fiber, and nitrocellulose) and two additional porous membranes with upstream sample preparation capabilities (polyethersulfone and polycarbonate). We compared amplification efficiency from four separate DNA and RNA targets (Bordetella pertussis, Chlamydia trachomatis, Neisseria gonorrhoeae, and Influenza A H1N1) within these materials using two different isothermal amplification schemes, helicase dependent amplification (tHDA) and loop-mediated isothermal amplification (LAMP), and traditional PCR. We found that the current paper-based diagnostic membranes inhibited nucleic acid amplification when compared to membrane-free controls; however, polyethersulfone allowed for efficient amplification in both LAMP and tHDA reactions. Further, observing the performance of traditional PCR amplification within these membranes was not predicative of their effects on in situ LAMP and tHDA. Polyethersulfone is a new material for paper-based nucleic acid amplification, yet provides an optimal support for rapid molecular diagnostics for point-of-care applications.

  13. A Practical Illustration of Multidimensional Diagnostic Skills Profiling: Comparing Results from Confirmatory Factor Analysis and Diagnostic Classification Models

    ERIC Educational Resources Information Center

    Kunina-Habenicht, Olga; Rupp, Andre A.; Wilhelm, Oliver

    2009-01-01

    In recent years there has been an increasing international interest in fine-grained diagnostic inferences on multiple skills for formative purposes. A successful provision of such inferences that support meaningful instructional decision-making requires (a) careful diagnostic assessment design coupled with (b) empirical support for the structure…

  14. Diagnostic Performance of Dual-Energy CT Stress Myocardial Perfusion Imaging: Direct Comparison With Cardiovascular MRI

    PubMed Central

    Ko, Sung Min; Song, Meong Gun; Chee, Hyun Kun; Hwang, Hweung Kon; Feuchtner, Gudrun Maria; Min, James K.

    2014-01-01

    OBJECTIVE The purpose of this study was to assess the diagnostic performance of stress perfusion dual-energy CT (DECT) and its incremental value when used with coronary CT angiography (CTA) for identifying hemodynamically significant coronary artery disease. SUBJECTS AND METHODS One hundred patients with suspected or known coronary artery disease without chronic myocardial infarction detected with coronary CTA underwent stress perfusion DECT, stress cardiovascular perfusion MRI, and invasive coronary angiography (ICA). Stress perfusion DECT and cardiovascular stress perfusion MR images were used for detecting perfusion defects. Coronary CTA and ICA were evaluated in the detection of ≥ 50% coronary stenosis. The diagnostic performance of coronary CTA for detecting hemodynamically significant stenosis was assessed before and after stress perfusion DECT on a pervessel basis with ICA and cardiovascular stress perfusion MRI as the reference standard. RESULTS The performance of stress perfusion DECT compared with cardiovascular stress perfusion MRI on a per-vessel basis in the detection of perfusion defects was sensitivity, 89%; specificity, 74%; positive predictive value, 73%; negative predictive value, 90%. Per segment, these values were sensitivity, 76%; specificity, 80%; positive predictive value, 63%; and negative predictive value, 88%. Compared with ICA and cardiovascular stress perfusion MRI per vessel territory the sensitivity, specificity, positive predictive value, and negative predictive value of coronary CTA were 95%, 61%, 61%, and 95%. The values for stress perfusion DECT were 92%, 72%, 68%, and 94%. The values for coronary CTA and stress perfusion DECT were 88%, 79%, 73%, and 91%. The ROC AUC increased from 0.78 to 0.84 (p = 0.02) with the use of coronary CTA and stress perfusion DECT compared with coronary CTA alone. CONCLUSION Stress perfusion DECT plays a complementary role in enhancing the accuracy of coronary CTA for identifying hemodynamically

  15. Clinics in diagnostic imaging (82). Lesser trochanter metastasis.

    PubMed

    Peh, W C G; Muttarak, M

    2003-02-01

    A 73-year-old woman who had previous mastectomy for breast carcinoma presented with persistent pain over the left hip area for two to three months. Pelvic radiograph showed an expanded osteolytic lesion involving the lesser trochanter of the left femur, with adjacent ill-defined destructive changes. She subsequently developed a displaced pathological fracture through the lesser trochanteric metastasis. The clinical features and pathophysiology of bone metastases are discussed. The role of imaging, with additional illustrative examples, is emphasised.

  16. Diagnostic Imaging of Detonation Waves for Waveshaper Development

    DTIC Science & Technology

    2009-07-01

    charge in toward the centre. This pressure which is greater than the normal detonation pressure of the explosive causes an increase in energy ...powerful jet. For successful charge initiation sufficient explosive energy from the detonator and/or booster is required to successfully detonate the...sympathetic detonation (iv) Air-gap compression – ionisation due to adiabatic compression of air gap 2 DSTO-TR-2309 3.1 Direct Imaging Direct

  17. Innovations in diagnostic imaging of localized prostate cancer.

    PubMed

    Pummer, Karl; Rieken, Malte; Augustin, Herbert; Gutschi, Thomas; Shariat, Shahrokh F

    2014-08-01

    In recent years, various imaging modalities have been developed to improve diagnosis, staging, and localization of early-stage prostate cancer (PCa). A MEDLINE literature search of the time frame between 01/2007 and 06/2013 was performed on imaging of localized PCa. Conventional transrectal ultrasound (TRUS) is mainly used to guide prostate biopsy. Contrast-enhanced ultrasound is based on the assumption that PCa tissue is hypervascularized and might be better identified after intravenous injection of a microbubble contrast agent. However, results on its additional value for cancer detection are controversial. Computer-based analysis of the transrectal ultrasound signal (C-TRUS) appears to detect cancer in a high rate of patients with previous biopsies. Real-time elastography seems to have higher sensitivity, specificity, and positive predictive value than conventional TRUS. However, the method still awaits prospective validation. The same is true for prostate histoscanning, an ultrasound-based method for tissue characterization. Currently, multiparametric MRI provides improved tissue visualization of the prostate, which may be helpful in the diagnosis and targeting of prostate lesions. However, most published series are small and suffer from variations in indication, methodology, quality, interpretation, and reporting. Among ultrasound-based techniques, real-time elastography and C-TRUS seem the most promising techniques. Multiparametric MRI appears to have advantages over conventional T2-weighted MRI in the detection of PCa. Despite these promising results, currently, no recommendation for the routine use of these novel imaging techniques can be made. Prospective studies defining the value of various imaging modalities are urgently needed.

  18. Evaluation of subjective image quality in relation to diagnostic task for cone beam computed tomography with different fields of view.

    PubMed

    Lofthag-Hansen, Sara; Thilander-Klang, Anne; Gröndahl, Kerstin

    2011-11-01

    To evaluate subjective image quality for two diagnostic tasks, periapical diagnosis and implant planning, for cone beam computed tomography (CBCT) using different exposure parameters and fields of view (FOVs). Examinations were performed in posterior part of the jaws on a skull phantom with 3D Accuitomo (FOV 3 cm×4 cm) and 3D Accuitomo FPD (FOVs 4 cm×4 cm and 6 cm×6 cm). All combinations of 60, 65, 70, 75, 80 kV and 2, 4, 6, 8, 10 mA with a rotation of 180° and 360° were used. Dose-area product (DAP) value was determined for each combination. The images were presented, displaying the object in axial, cross-sectional and sagittal views, without scanning data in a random order for each FOV and jaw. Seven observers assessed image quality on a six-point rating scale. Intra-observer agreement was good (κw=0.76) and inter-observer agreement moderate (κw=0.52). Stepwise logistic regression showed kV, mA and diagnostic task to be the most important variables. Periapical diagnosis, regardless jaw, required higher exposure parameters compared to implant planning. Implant planning in the lower jaw required higher exposure parameters compared to upper jaw. Overall ranking of FOVs gave 4 cm×4 cm, 6 cm×6 cm followed by 3 cm×4 cm. This study has shown that exposure parameters should be adjusted according to diagnostic task. For this particular CBCT brand a rotation of 180° gave good subjective image quality, hence a substantial dose reduction can be achieved without loss of diagnostic information. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  19. Predictive capabilities of statistical learning methods for lung nodule malignancy classification using diagnostic image features: an investigation using the Lung Image Database Consortium dataset

    NASA Astrophysics Data System (ADS)

    Hancock, Matthew C.; Magnan, Jerry F.

    2017-03-01

    To determine the potential usefulness of quantified diagnostic image features as inputs to a CAD system, we investigate the predictive capabilities of statistical learning methods for classifying nodule malignancy, utilizing the Lung Image Database Consortium (LIDC) dataset, and only employ the radiologist-assigned diagnostic feature values for the lung nodules therein, as well as our derived estimates of the diameter and volume of the nodules from the radiologists' annotations. We calculate theoretical upper bounds on the classification accuracy that is achievable by an ideal classifier that only uses the radiologist-assigned feature values, and we obtain an accuracy of 85.74 (+/-1.14)% which is, on average, 4.43% below the theoretical maximum of 90.17%. The corresponding area-under-the-curve (AUC) score is 0.932 (+/-0.012), which increases to 0.949 (+/-0.007) when diameter and volume features are included, along with the accuracy to 88.08 (+/-1.11)%. Our results are comparable to those in the literature that use algorithmically-derived image-based features, which supports our hypothesis that lung nodules can be classified as malignant or benign using only quantified, diagnostic image features, and indicates the competitiveness of this approach. We also analyze how the classification accuracy depends on specific features, and feature subsets, and we rank the features according to their predictive power, statistically demonstrating the top four to be spiculation, lobulation, subtlety, and calcification.

  20. Diagnostic accuracy of thallium-201 myocardial perfusion imaging

    SciTech Connect

    Beller, G.A. )

    1991-09-01

    Myocardial thallium-201 (Tl-201) imaging performed in conjunction with exercise stress has enhanced the accuracy of detecting coronary artery disease among patients with chest pain. Sensitivity and specificity of qualitative visual Tl-201 scintigraphy for detection of coronary artery disease average 84% and 87%, respectively. Quantitative analysis of planar Tl-201 scintigrams has yielded sensitivity and specificity in the 90% range. Single photon emission computed tomographic imaging is associated with even higher sensitivity but with specificity in the 82-85% range. Perfusion defects representing ischemia can now be distinguished from scar by demonstration of delayed Tl-201 redistribution or enhanced uptake after reinjection of a second dose of Tl-201. Stenoses of the left circumflex coronary artery are less easily detected than lesions of the right and left anterior descending coronary arteries. False-positive Tl-201 perfusion defects may occur as a result of attenuation artifacts, most often caused by overlying breast tissue or by a high left hemidiaphragm. Patient motion during acquisition of single photon emission computed tomographic images results in artifactual defects on reconstruction. Abnormal Tl-201 uptake has been noted in patients with (1) left bundle branch block and normal coronary arteries, (2) hypertrophic cardiomyopathy, and (3) progressive systemic sclerosis.

  1. Optoacoustic imaging of absorbing objects in a turbid medium: ultimate sensitivity and application to breast cancer diagnostics

    NASA Astrophysics Data System (ADS)

    Khokhlova, Tatiana D.; Pelivanov, Ivan M.; Kozhushko, Victor V.; Zharinov, Alexei N.; Solomatin, Vladimir S.; Karabutov, Alexander A.

    2007-01-01

    One of the major medical applications of optoacoustic (OA) tomography is in the diagnostics of early-stage breast cancer. A numerical approach was developed to characterize the following parameters of an OA imaging system: resolution, maximum depth at which the tumor can be detected, and image contrast. The parameters of the 64-element focused array transducer were obtained. The results of numerical modeling were compared with known analytical solutions and further validated by phantom experiments. The OA images of a 3 mm piece of bovine liver immersed in diluted milk at various depths were obtained. Based on the results of modeling, a signal filtering algorithm for OA image contrast enhancement has been proposed.

  2. Optoacoustic imaging of absorbing objects in a turbid medium: ultimate sensitivity and application to breast cancer diagnostics

    SciTech Connect

    Khokhlova, Tatiana D.; Pelivanov, Ivan M.; Kozhushko, Victor V.; Zharinov, Alexei N.; Solomatin, Vladimir S.; Karabutov, Alexander A

    2007-01-10

    One of the major medical applications of optoacoustic (OA) tomography is in the diagnostics of early-stage breast cancer. A numerical approach was developed to characterize the following parameters of an OA imaging system: resolution, maximum depth at which the tumor can be detected, and image contrast. The parameters of the 64-element focused array transducer were obtained. The results of numerical modeling were compared with known analytical solutions and further validated by phantom experiments. The OA images of a3 mm piece of bovine liver immersed in diluted milk at various depths were obtained. Based on the results of modeling, a signal filtering algorithm for OA image contrast enhancement has been proposed.

  3. Diagnostic ultrasound at MACH 20: retroperitoneal and pelvic imaging in space.

    PubMed

    Jones, J A; Sargsyan, A E; Barr, Y R; Melton, S; Hamilton, D R; Dulchavsky, S A; Whitson, P A

    2009-07-01

    An operationally available diagnostic imaging capability augments spaceflight medical support by facilitating the diagnosis, monitoring and treatment of medical or surgical conditions, by improving medical outcomes and, thereby, by lowering medical mission impacts and the probability of crew evacuation due to medical causes. Microgravity-related physiological changes occurring during spaceflight can affect the genitourinary system and potentially cause conditions such as urinary retention or nephrolithiasis for which ultrasonography (U/S) would be a useful diagnostic tool. This study describes the first genitourinary ultrasound examination conducted in space, and evaluates image quality, frame rate, resolution requirements, real-time remote guidance of nonphysician crew medical officers and evaluation of on-orbit tools that can augment image acquisition. A nonphysician crew medical officer (CMO) astronaut, with minimal training in U/S, performed a self-examination of the genitourinary system onboard the International Space Station, using a Philips/ATL Model HDI-5000 ultrasound imaging unit located in the International Space Station Human Research Facility. The CMO was remotely guided by voice commands from experienced, earth-based sonographers stationed in Mission Control Center in Houston. The crewmember, with guidance, was able to acquire all of the target images. Real-time and still U/S images received at Mission Control Center in Houston were of sufficient quality for the images to be diagnostic for multiple potential genitourinary applications. Microgravity-based ultrasound imaging can provide diagnostic quality images of the retroperitoneum and pelvis, offering improved diagnosis and treatment for onboard medical contingencies. Successful completion of complex sonographic examinations can be obtained even with minimally trained nonphysician ultrasound operators, with the assistance of ground-based real-time guidance.

  4. Development of horn antenna mixer array with internal local oscillator module for microwave imaging diagnostics

    SciTech Connect

    Kuwahara, D.; Ito, N.; Nagayama, Y.; Yoshinaga, T.; Yamaguchi, S.; Yoshikawa, M.; Kohagura, J.; Sugito, S.; Kogi, Y.; Mase, A.

    2014-11-15

    A new antenna array is proposed in order to improve the sensitivity and complexity of microwave imaging diagnostics systems such as a microwave imaging reflectometry, a microwave imaging interferometer, and an electron cyclotron emission imaging. The antenna array consists of five elements: a horn antenna, a waveguide-to-microstrip line transition, a mixer, a local oscillation (LO) module, and an intermediate frequency amplifier. By using an LO module, the LO optics can be removed, and the supplied LO power to each element can be equalized. We report details of the antenna array and characteristics of a prototype antenna array.

  5. Phase-contrast enhanced mammography: A new diagnostic tool for breast imaging

    NASA Astrophysics Data System (ADS)

    Wang, Zhentian; Thuering, Thomas; David, Christian; Roessl, Ewald; Trippel, Mafalda; Kubik-Huch, Rahel A.; Singer, Gad; Hohl, Michael K.; Hauser, Nik; Stampanoni, Marco

    2012-07-01

    Phase contrast and scattering-based X-ray imaging can potentially revolutionize the radiological approach to breast imaging by providing additional and complementary information to conventional, absorption-based methods. We investigated native, non-fixed whole breast samples using a grating interferometer with an X-ray tube-based configuration. Our approach simultaneously recorded absorption, differential phase contrast and small-angle scattering signals. The results show that this novel technique - combined with a dedicated image fusion algorithm - has the potential to deliver enhanced breast imaging with complementary information for an improved diagnostic process.

  6. Phase-contrast enhanced mammography: A new diagnostic tool for breast imaging

    SciTech Connect

    Wang Zhentian; Thuering, Thomas; David, Christian; Roessl, Ewald; Trippel, Mafalda; Kubik-Huch, Rahel A.; Singer, Gad; Hohl, Michael K.; Hauser, Nik; Stampanoni, Marco

    2012-07-31

    Phase contrast and scattering-based X-ray imaging can potentially revolutionize the radiological approach to breast imaging by providing additional and complementary information to conventional, absorption-based methods. We investigated native, non-fixed whole breast samples using a grating interferometer with an X-ray tube-based configuration. Our approach simultaneously recorded absorption, differential phase contrast and small-angle scattering signals. The results show that this novel technique - combined with a dedicated image fusion algorithm - has the potential to deliver enhanced breast imaging with complementary information for an improved diagnostic process.

  7. Development of horn antenna mixer array with internal local oscillator module for microwave imaging diagnostics.

    PubMed

    Kuwahara, D; Ito, N; Nagayama, Y; Yoshinaga, T; Yamaguchi, S; Yoshikawa, M; Kohagura, J; Sugito, S; Kogi, Y; Mase, A

    2014-11-01

    A new antenna array is proposed in order to improve the sensitivity and complexity of microwave imaging diagnostics systems such as a microwave imaging reflectometry, a microwave imaging interferometer, and an electron cyclotron emission imaging. The antenna array consists of five elements: a horn antenna, a waveguide-to-microstrip line transition, a mixer, a local oscillation (LO) module, and an intermediate frequency amplifier. By using an LO module, the LO optics can be removed, and the supplied LO power to each element can be equalized. We report details of the antenna array and characteristics of a prototype antenna array.

  8. Development of horn antenna mixer array with internal local oscillator module for microwave imaging diagnostics

    NASA Astrophysics Data System (ADS)

    Kuwahara, D.; Ito, N.; Nagayama, Y.; Yoshinaga, T.; Yamaguchi, S.; Yoshikawa, M.; Kohagura, J.; Sugito, S.; Kogi, Y.; Mase, A.

    2014-11-01

    A new antenna array is proposed in order to improve the sensitivity and complexity of microwave imaging diagnostics systems such as a microwave imaging reflectometry, a microwave imaging interferometer, and an electron cyclotron emission imaging. The antenna array consists of five elements: a horn antenna, a waveguide-to-microstrip line transition, a mixer, a local oscillation (LO) module, and an intermediate frequency amplifier. By using an LO module, the LO optics can be removed, and the supplied LO power to each element can be equalized. We report details of the antenna array and characteristics of a prototype antenna array.

  9. Multimodality Diagnostic Imaging in Unilateral Acute Idiopathic Maculopathy

    PubMed Central

    Jung, Cecilia S.; Payne, John F.; Bergstrom, Chris S.; Cribbs, Blaine E.; Yan, Jiong; Hubbard, G. Baker; Olsen, Timothy W.; Yeh, Steven

    2014-01-01

    Objective To describe the clinical features and imaging characteristics in unilateral acute idiopathic maculopathy (UAIM). Methods This is a retrospective review of four patients diagnosed with UAIM. Clinical characteristics (age, symptoms, Snellen visual acuity (VA), and funduscopic features) and images from spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence (FAF), fluorescein (FA), and indocyanine green (ICG) angiography were analyzed. Results The median age at presentation was 31 years (range 27–52 years). The median interval between symptom onset and presentation was four weeks (range 1–20 weeks). Associated systemic findings included a viral prodrome (50%), orchitis (50%), hand-foot-mouth disease (25%), and positive Coxsackie virus titers (50%). The median presenting VA was 20/400 (range 20/70–1/400), which improved to 20/30 (range 20/20–20/60) at final follow-up. The median follow-up time was 6 weeks (range 0–8 weeks). Early in the disease course, the central macula developed irregular, circular areas of white-grey discoloration. Following recovery, the macula had a stippled retinal pigment epithelium characterized by rarefaction and hyperplasia. FA demonstrated irregular early hyperfluorescence and late subretinal hyperfluorescence. SD-OCT showed a partially reversible disruption of the outer photoreceptor layer. FAF initially revealed stippled autofluorescence that eventually became more hypoautofluorescent. ICG showed “moth-eaten” appearing choroidal vasculature, suggestive of choroidal inflammation. Conclusions The imaging characteristics highlight the structural changes during the active and resolution phases of UAIM. The visual recovery correlates with structural changes and suggests that the pathogenesis involves inflammation of the inner choroid, retinal pigment epithelium, and outer photoreceptor complex that is partially reversible. PMID:22232475

  10. Nanoparticles for biomedical imaging, therapy, and quantitative diagnostics

    NASA Astrophysics Data System (ADS)

    Yust, Brian G.

    Nanoparticles and nanomaterials are known to exhibit extraordinary characteristics and have a wide range of application which utilizes their unique properties. In particular, nanoparticles have shown great promise towards advancing the state of biological and biomedical techniques such as in vivo and in vitro imaging modalities, biosensing, and disease detection and therapy. Nanocrystalline hosts: NaYF4, KYF4, KGdF4, NaMF3, and KMF3 (M=Mg, Ba, Mn, Fe, Co, Ni, Cr) doped with rare earth ions have been synthesized by thermolysis, solvothermal, and hydrothermal methods. The morphology and spectroscopic properties have been thoroughly characterized. These nanoparticles (NP) are particularly useful for biomedical purposes since both the exciting and emitting wavelengths are in the near-infrared, where most tissues do not strongly absorb or scatter light. In vivo and in vitro imaging was performed with a 980 nm excitation source. Finally, NPs were conjugated with zinc phthalocyanine, a photosensitizer with a large absorption coefficient in the red and NIR regions, to illustrate the efficacy of these NPs as a platform for dual-mode infrared-activated imaging and photodynamic platforms. In addition, nonlinear optical nanomaterials, such as BaTiO3 and Ag@BaTiO3, were also synthesized and characterized. The nonlinear optical properties were investigated, and it is demonstrated that these nanoparticles can produce phase conjugate waves when used in a counterpropagating four wave mixing setup. The third order susceptibility is quantified using the z-scan technique, and the toxicity of these nanoparticles is also explored.

  11. High-dynamic-range pixel architectures for diagnostic medical imaging

    NASA Astrophysics Data System (ADS)

    Karim, Karim S.; Yin, Sherman; Nathan, Arokia; Rowlands, John A.

    2004-05-01

    One approach to increase pixel signal-to-noise ratio (SNR) in low noise digital fluoroscopy is to employ in-situ pixel amplification via current-mediated active pixel sensors (C-APS). Experiments reveal a reduction in readout noise and indicate that an a-Si C-APS, coupled together with an established X-ray detection technology such as amorphous selenium (a-Se), can meet the stringent requirements (of < 1000 noise electrons) for digital X-ray fluoroscopy. A challenge with the C-APS circuit is the presence of a small-signal input linearity constraint. While using such a pixel amplifier for real-time fluoroscopy (where the exposure level is small) is feasible, the voltage change at the amplifier input is much higher in chest radiography or mammography due to the larger X-ray exposure levels. The larger input voltage causes the C-APS output to be non-linear thus reducing the pixel dynamic range. In addition, the resulting larger pixel output current causes the external column amplifier to saturate further reducing the pixel dynamic range. In this research, we investigate two alternate amplified pixel architectures that exhibit higher dynamic range. The test pixels are designed and simulated using an a-Si TFT model implemented in Verilog-A and results indicate a linear performance, high dynamic range, and a programmable circuit gain via choice of supply voltage and sampling time. These high dynamic range pixel architectures have the potential to enable a large area, active matrix flat panel imager (AMFPI) to switch instantly between low exposure, fluoroscopic imaging and higher exposure radiographic imaging modes. Lastly, the high dynamic range pixel circuits are suitable for integration with on-panel multiplexers for both gate and data lines, which can further reduce circuit complexity.

  12. Diagnostic imaging in a patient with an acute knee injury.

    PubMed

    Sago, Carrie E; Labuda, Craig S

    2013-01-01

    The patient was a 23-year-old man, currently serving in a military airborne operations unit. During a jump training exercise, the patient's right lower extremity became entangled in his parachute equipment upon exiting the aircraft, which caused hyperextension and valgus forces upon his right knee. Due to concern for a fracture, the patient was transported to an emergency department, where conventional radiographs were completed and interpreted by a radiologist as negative for a fracture. Following further physical examination by a physical therapist, magnetic resonance imaging of the right knee was ordered, revealing ruptures of the anterior cruciate ligament and medial collateral ligament.

  13. A method for comparing beam-hardening filter materials for diagnostic radiology.

    PubMed

    Jennings, R J

    1988-01-01

    The necessity for using adequate beam filtration in diagnostic radiology is well known. Although aluminum is the most widely used filter material for diagnostic x-ray applications, the possibility that other materials might have superior properties has prompted a number of studies that have attempted to determine both the type and the amount of filtration most appropriate for a given situation. This paper describes a method based on precise matching of spectral shape that permits the absolute ranking of beam-hardening materials. Matching of spectral shape ensures equality of such parameters as image contrast and patient dose. Spectrally equivalent filters can then be ranked on the basis of the transmission of one relative to another. Following the development of the theory behind the method and an algorithm for implementing it, the method is applied to the evaluation of a variety of materials for use as filters in diagnostic radiology. Experimental verification of a few of the calculated results is also described. Both calculated and experimental results show that normal aluminum filters are about 10% less efficient than filters of materials such as copper, brass, or iron. Since the approach followed here was the basis for several early investigations of filtration for orthovoltage therapy, a brief comparison of results from these early reports with results calculated using the method developed here is also presented.

  14. Comparison of midazolam and propofol for sedation in pediatric diagnostic imaging studies.

    PubMed

    Sebe, Ahmet; Yilmaz, Hayri Levent; Koseoglu, Zikret; Ay, Mehmet Oguzhan; Gulen, Muge

    2014-05-01

    This study aims to compare the efficacy of propofol and midazolam in terms of adverse effect potentials and to determine the appropriate strategy for pediatric procedural sedation. A total of 200 pediatric patients (aged < 14 years) undergoing diagnostic procedures were recruited for this nonrandomized prospective controlled cohort study. The patients were assigned to 2 treatment arms: either propofol (Group 1: IV bolus dose of 2 mg/kg during a 2-minute period, IV maintenance dose of 100 mcg/kg/min) or midazolam (Group 2: IV bolus dose of 0.15 mg/kg during a period of 2 to 3 minutes) to achieve sedation. Demographic data, body weight, and clinical status of the patients were evaluated and recorded. The vital signs and sedation levels (ie, Ramsay sedation scale scores) were evaluated and recorded, as well as the complications detected and medications administered in 10-minute intervals throughout the sedation procedure. Findings between the study arms were compared. Arterial blood pressures decreased significantly in both groups (P = 0.001). The patients in Group 1 experienced a greater difference in diastolic blood pressure (P = 0.001) than those in Group 2. Sedation scores in Group 1 were more favorable (P = 0.014) and reached the appropriate sedation level in a shorter time than those in Group 2 (P = 0.010). Likewise, recovery time of patients was shorter in Group 1 than in Group 2 (P = 0.010). Hypoxia was found to be more common in the propofol group, but the difference was not significant (P = 0.333). Propofol seems to be more effective, achieve the appropriate sedation level more quickly, and provide a faster onset of sedation than midazolam in pediatric procedural sedation and analgesia. Propofol is preferred for imaging studies (computed tomography and magnetic resonance imaging) to reduce the occurrence of undesired motion artefacts. Although both drugs are safe to use for sedation before pediatric imaging procedures, propofol is preferred with appropriate

  15. Application of Six Sigma methodology to a diagnostic imaging process.

    PubMed

    Taner, Mehmet Tolga; Sezen, Bulent; Atwat, Kamal M

    2012-01-01

    This paper aims to apply the Six Sigma methodology to improve workflow by eliminating the causes of failure in the medical imaging department of a private Turkish hospital. Implementation of the design, measure, analyse, improve and control (DMAIC) improvement cycle, workflow chart, fishbone diagrams and Pareto charts were employed, together with rigorous data collection in the department. The identification of root causes of repeat sessions and delays was followed by failure, mode and effect analysis, hazard analysis and decision tree analysis. The most frequent causes of failure were malfunction of the RIS/PACS system and improper positioning of patients. Subsequent to extensive training of professionals, the sigma level was increased from 3.5 to 4.2. The data were collected over only four months. Six Sigma's data measurement and process improvement methodology is the impetus for health care organisations to rethink their workflow and reduce malpractice. It involves measuring, recording and reporting data on a regular basis. This enables the administration to monitor workflow continuously. The improvements in the workflow under study, made by determining the failures and potential risks associated with radiologic care, will have a positive impact on society in terms of patient safety. Having eliminated repeat examinations, the risk of being exposed to more radiation was also minimised. This paper supports the need to apply Six Sigma and present an evaluation of the process in an imaging department.

  16. Correlation of diagnostic ultrasound and radionuclide imaging in scrotal disease

    SciTech Connect

    Chen, D.C.P.; Holder, L.E.; Kaplan, G.N.

    1984-01-01

    A retrospective study was performed to evaluate the usefulness of scrotal ultrasound imaging (SU) and radionuclide scrotal imaging (RSI) in 43 patients (pts), age: 16-75. Twenty-two of them complained of scrotal pain; 18 had a scrotal mass; and 4 had a history of trauma. The final diagnoses were conformed by surgery (n = 21) and long-term follow-up (n = 22) and included 4 late phase and 1 early testicular torsion (TT), 11 acute epididymitis (AE), 4 subacute epididymitis (SE), 5 malignant tumors, 3 testicular atrophy, 2 intratesticular hematomas, 10 hydroceles or other cystic lesions, and miscellaneous. In pts with scrotal pain, 3/4 with late phase TT were correctly diagnosed, while one pt with early TT and 11/15 with AE or SE were not diagnosed by SU. All of them were correctly diagnosed with RSI except one with scrotal cyst. SU was able to separate cystic masses (n = 10) from solid masses (n = 6), but cannot separate malignant from benign lesions. SU was excellent in detecting 19 hydroceles and 2 intratesticular hematomas, while 3 lesions < 1 cm. were not seen in RSI. The authors concluded that SU is useful in pts with scrotal mass to separate solid from cystic lesions. However, SU is unable to differentiate the acute epididymitis from early testicular torsion. In pts with acute scrotal pain, SU is not helpful and RSI should still be the first study performed.

  17. [Wernicke-Korsakoff syndrome: diagnostic contribution of magnetic resonance imaging].

    PubMed

    Varnet, O; de Seze, J; Soto-Ares, G; Tiberghien, F; Caparros-Lefebvre, D; Daems, C; Pasquier, F; Pruvo, J P; Destée, A; Vermesch, P

    2002-12-01

    Data regarding the magnetic resonance imaging (MRI) features in Wernicke-Korsakoff syndrome (WKS) are scarce. WKS usually combines a cerebellar syndrome, oculomotor disorder and confusion. The aim of this study was to determine more precisely the clinical presentation of WKS and the frequency and topography of MRI abnormalities. Furthermore, we try to assess the prognostic value of both clinical signs and MRI abnormalities. We retrospectively studied 25 patients with WKS in which an MRI was available. We assessed the initial clinical presentation and the outcome. We also analyzed the frequency and the location of MRI lesions. We then correlated clinical and MRI data with the clinical outcome. Eleven patients (44 p. 100) had the full WKS. Fourteen of the 25 patients (56 p. 100) had a poor evolution. The occurrence of full WKS was correlated with a poor outcome (p < 0.02). Signal abnormalities on T2-weighted images were found in the periacqueducal region, in the thalami or in the mamillar bodies in 16 cases (64 p. 100). There was a correlation between an hypersignal in at least one region and a poor clinical outcome (p < 0.02). Our study demonstrates the high frequency of brain MRI lesions in WKS and the correlation of both initial clinical signs and MRI abnormalities with a poor clinical outcome.

  18. Using complex networks towards information retrieval and diagnostics in multidimensional imaging

    PubMed Central

    Banerjee, Soumya Jyoti; Azharuddin, Mohammad; Sen, Debanjan; Savale, Smruti; Datta, Himadri; Dasgupta, Anjan Kr; Roy, Soumen

    2015-01-01

    We present a fresh and broad yet simple approach towards information retrieval in general and diagnostics in particular by applying the theory of complex networks on multidimensional, dynamic images. We demonstrate a successful use of our method with the time series generated from high content thermal imaging videos of patients suffering from the aqueous deficient dry eye (ADDE) disease. Remarkably, network analyses of thermal imaging time series of contact lens users and patients upon whom Laser-Assisted in situ Keratomileusis (Lasik) surgery has been conducted, exhibit pronounced similarity with results obtained from ADDE patients. We also propose a general framework for the transformation of multidimensional images to networks for futuristic biometry. Our approach is general and scalable to other fluctuation-based devices where network parameters derived from fluctuations, act as effective discriminators and diagnostic markers. PMID:26626047

  19. Using complex networks towards information retrieval and diagnostics in multidimensional imaging.

    PubMed

    Banerjee, Soumya Jyoti; Azharuddin, Mohammad; Sen, Debanjan; Savale, Smruti; Datta, Himadri; Dasgupta, Anjan Kr; Roy, Soumen

    2015-12-02

    We present a fresh and broad yet simple approach towards information retrieval in general and diagnostics in particular by applying the theory of complex networks on multidimensional, dynamic images. We demonstrate a successful use of our method with the time series generated from high content thermal imaging videos of patients suffering from the aqueous deficient dry eye (ADDE) disease. Remarkably, network analyses of thermal imaging time series of contact lens users and patients upon whom Laser-Assisted in situ Keratomileusis (Lasik) surgery has been conducted, exhibit pronounced similarity with results obtained from ADDE patients. We also propose a general framework for the transformation of multidimensional images to networks for futuristic biometry. Our approach is general and scalable to other fluctuation-based devices where network parameters derived from fluctuations, act as effective discriminators and diagnostic markers.

  20. Using complex networks towards information retrieval and diagnostics in multidimensional imaging

    NASA Astrophysics Data System (ADS)

    Banerjee, Soumya Jyoti; Azharuddin, Mohammad; Sen, Debanjan; Savale, Smruti; Datta, Himadri; Dasgupta, Anjan Kr; Roy, Soumen

    2015-12-01

    We present a fresh and broad yet simple approach towards information retrieval in general and diagnostics in particular by applying the theory of complex networks on multidimensional, dynamic images. We demonstrate a successful use of our method with the time series generated from high content thermal imaging videos of patients suffering from the aqueous deficient dry eye (ADDE) disease. Remarkably, network analyses of thermal imaging time series of contact lens users and patients upon whom Laser-Assisted in situ Keratomileusis (Lasik) surgery has been conducted, exhibit pronounced similarity with results obtained from ADDE patients. We also propose a general framework for the transformation of multidimensional images to networks for futuristic biometry. Our approach is general and scalable to other fluctuation-based devices where network parameters derived from fluctuations, act as effective discriminators and diagnostic markers.

  1. Review of Quantitative Ultrasound: Envelope Statistics and Backscatter Coefficient Imaging and Contributions to Diagnostic Ultrasound.

    PubMed

    Oelze, Michael L; Mamou, Jonathan

    2016-02-01

    Conventional medical imaging technologies, including ultrasound, have continued to improve over the years. For example, in oncology, medical imaging is characterized by high sensitivity, i.e., the ability to detect anomalous tissue features, but the ability to classify these tissue features from images often lacks specificity. As a result, a large number of biopsies of tissues with suspicious image findings are performed each year with a vast majority of these biopsies resulting in a negative finding. To improve specificity of cancer imaging, quantitative imaging techniques can play an important role. Conventional ultrasound B-mode imaging is mainly qualitative in nature. However, quantitative ultrasound (QUS) imaging can provide specific numbers related to tissue features that can increase the specificity of image findings leading to improvements in diagnostic ultrasound. QUS imaging can encompass a wide variety of techniques including spectral-based parameterization, elastography, shear wave imaging, flow estimation, and envelope statistics. Currently, spectral-based parameterization and envelope statistics are not available on most conventional clinical ultrasound machines. However, in recent years, QUS techniques involving spectral-based parameterization and envelope statistics have demonstrated success in many applications, providing additional diagnostic capabilities. Spectral-based techniques include the estimation of the backscatter coefficient (BSC), estimation of attenuation, and estimation of scatterer properties such as the correlation length associated with an effective scatterer diameter (ESD) and the effective acoustic concentration (EAC) of scatterers. Envelope statistics include the estimation of the number density of scatterers and quantification of coherent to incoherent signals produced from the tissue. Challenges for clinical application include correctly accounting for attenuation effects and transmission losses and implementation of QUS on

  2. The effects of noise reduction, sharpening, enhancement, and image magnification on diagnostic accuracy of a photostimulable phosphor system in the detection of non-cavitated approximal dental caries.

    PubMed

    Kajan, Zahra Dalili; Tayefeh Davalloo, Reza; Tavangar, Mayam; Valizade, Fatemeh

    2015-06-01

    Contrast, sharpness, enhancement, and density can be changed in digital systems. The important question is to what extent the changes in these variables affect the accuracy of caries detection. Forty eight extracted human posterior teeth with healthy or proximal caries surfaces were imaged using a photostimulable phosphor (PSP) sensor. All original images were processed using a six-step method: (1) applying "Sharpening 2" and "Noise Reduction" processing options to the original images; (2) applying the "Magnification 1:3" option to the image obtained in the first step; (3) enhancing the original images by using the "Diagonal/" option; (4) reviewing the changes brought about by the third step of image processing and then, applying "Magnification 1:3"; (5) applying "Sharpening UM" to the original images; and (6) analyzing the changes brought about by the fifth step of image processing, and finally, applying "Magnification 1:3." Three observers evaluated the images. The tooth sections were evaluated histologically as the gold standard. The diagnostic accuracy of the observers was compared using a chi-squared test. The accuracy levels irrespective of the image processing method ranged from weak (18.8%) to intermediate (54.2%), but the highest accuracy was achieved at the sixth image processing step. The overall diagnostic accuracy level showed a statistically significant difference (p=0.0001). This study shows that the application of "Sharpening UM" along with the "Magnification 1:3" processing option improved the diagnostic accuracy and the observer agreement more effectively than the other processing procedures.

  3. Tomosynthesis for the early detection of pulmonary emphysema: diagnostic performance compared with chest radiography, using multidetector computed tomography as reference.

    PubMed

    Yamada, Yoshitake; Jinzaki, Masahiro; Hashimoto, Masahiro; Shiomi, Eisuke; Abe, Takayuki; Kuribayashi, Sachio; Ogawa, Kenji

    2013-08-01

    To compare the diagnostic performance of tomosynthesis with that of chest radiography for the detection of pulmonary emphysema, using multidetector computed tomography (MDCT) as reference. Forty-eight patients with and 63 without pulmonary emphysema underwent chest MDCT, tomosynthesis and radiography on the same day. Two blinded radiologists independently evaluated the tomosynthesis images and radiographs for the presence of pulmonary emphysema. Axial and coronal MDCT images served as the reference standard and the percentage lung volume with attenuation values of -950 HU or lower (LAA-950) was evaluated to determine the extent of emphysema. Receiver-operating characteristic (ROC) analysis and generalised estimating equations model were used. ROC analysis revealed significantly better performance (P < 0.0001) of tomosynthesis than radiography for the detection of pulmonary emphysema. The average sensitivity, specificity, positive predictive value and negative predictive value of tomosynthesis were 0.875, 0.968, 0.955 and 0.910, respectively, whereas the values for radiography were 0.479, 0.913, 0.815 and 0.697, respectively. For both tomosynthesis and radiography, the sensitivity increased with increasing LAA-950. The diagnostic performance of tomosynthesis was significantly superior to that of radiography for the detection of pulmonary emphysema. In both tomosynthesis and radiography, the sensitivity was affected by the LAA-950. • Tomosynthesis showed significantly better diagnostic performance for pulmonary emphysema than radiography. • Interobserver agreement for tomosynthesis was significantly higher than that for radiography. • Sensitivity increased with increasing LAA -950 in both tomosynthesis and radiography. • Tomosynthesis imparts a similar radiation dose to two projection chest radiography. • Radiation dose and cost of tomosynthesis are lower than those of MDCT.

  4. Near Infrared Imaging as a Diagnostic Tool for Detecting Enamel Demineralization: An in vivo Study

    NASA Astrophysics Data System (ADS)

    Lucas, Seth Adam

    Background and Objectives: For decades there has been an effort to develop alternative optical methods of imaging dental decay utilizing non-ionizing radiation methods. The purpose of this in-vivo study was to demonstrate whether NIR can be used as a diagnostic tool to evaluate dental caries and to compare the sensitivity and specificity of this method with that of conventional methods, including bitewing x-rays and visual inspection. Materials and Methods: 31 test subjects (n=31) from the UCSF orthodontic clinic undergoing orthodontic treatment with planned premolar extractions were recruited. Calibrated examiners performed caries detection examinations using conventional methods: bitewing radiographs and visual inspection. These findings were compared with the results from NIR examinations: transillumination and reflectance. To confirm the results found in the two different detection methods, a gold standard was used. After teeth were extracted, polarized light microscopy and transverse microradiography were performed. Results: A total of 87 premolars were used in the study. NIR identified the occlusal lesions with a sensitivity of 71% and a specificity of 77%, whereas, the visual examination had a sensitivity of only 40% and a specifity of 39%. For interproximal lesions halfway to DEJ, specificity remained constant, but sensitivity improved to 100% for NIR and 75% for x-rays. Conclusions: The results of this preliminary study demonstrate that NIR is just as effective at detecting enamel interproximal lesions as standard dental x-rays. NIR was more effective at detecting occlusal lesions than visual examination alone. NIR shows promise as an alternative diagnostic tool to the conventional methods of x-rays and visual examination and provides a non-ionizing radiation technique.

  5. Diagnostic accuracy and added value of dual-energy subtraction radiography compared to standard conventional radiography using computed tomography as standard of reference

    PubMed Central

    Martini, Katharina; Baessler, Marco; Baumueller, Stephan; Frauenfelder, Thomas

    2017-01-01

    Purpose To retrospectively evaluate diagnostic performance of dual-energy subtraction radiography (DESR) for interpretation of chest radiographs compared to conventional radiography (CR) using computed tomography (CT) as standard of reference. Material and methods A total of 199 patients (75 female, median age 67) were included in this institutional review board (IRB)-approved clinical trial. All patients were scanned in posteroanterior and lateral direction with dual-shot DE-technique. Chest CT was performed within ±72 hours. The system provides three types of images: bone weighted-image, soft tissue weighted-image, herein termed as DESR-images, and a standard image, termed CR-image (marked as CR-image). Images were evaluated by two radiologists for presence of inserted life support lines, pneumothorax, pleural effusion, infectious consolidation, interstitial lung changes, tumor, skeletal alterations, soft tissue alterations, aortic or tracheal calcification and pleural thickening. Inter-observer agreement between readers and diagnostic performance were calculated. McNemar’s test was used to test for significant differences. Results Mean inter-observer agreement throughout the investigated parameters was higher in DESR images compared to CR-images (kDESR = 0.935 vs. kCR = 0.858). DESR images provided significantly increased sensitivity compared to CR-images for the detection of infectious consolidations (42% vs. 62%), tumor (46% vs. 57%), interstitial lung changes (69% vs. 87%) and aortic or tracheal calcification (25 vs. 73%) (p<0.05). There were no significant differences in sensitivity for the detection of inserted life support lines, pneumothorax, pleural effusion, skeletal alterations, soft tissue alterations or pleural thickening (p>0.05). Conclusion DESR increases significantly the sensibility without affecting the specificity evaluating chest radiographs, with emphasis on the detection of interstitial lung diseases. PMID:28301584

  6. A Novel Hand-Held Optical Imager with Real-Time Coregistration Facilities Toward Diagnostic Mammography

    DTIC Science & Technology

    2011-01-01

    Journal Publications (1) S.J. Erickson, S.L. Martinez, J. Gonzalez, L. Caldera , and A. Godavarty. “Improved detection limits using a hand-held...Erickson, S. Martinez, J. Gonzalez, L. Caldera , and A. Godavarty. “Non- invasive Diagnostic Breast Imaging using a Hand-held Optical Imager...Proceedings of the 14th World Multi-Conference on Systems, Cybernetics and Informatics, 2010. (4) S.J. Erickson, S. Martinez, L. Caldera , and A

  7. Predicting diagnostic error in radiology via eye-tracking and image analytics: Preliminary investigation in mammography

    SciTech Connect

    Voisin, Sophie; Tourassi, Georgia D.; Pinto, Frank; Morin-Ducote, Garnetta; Hudson, Kathleen B.

    2013-10-15

    Purpose: The primary aim of the present study was to test the feasibility of predicting diagnostic errors in mammography by merging radiologists’ gaze behavior and image characteristics. A secondary aim was to investigate group-based and personalized predictive models for radiologists of variable experience levels.Methods: The study was performed for the clinical task of assessing the likelihood of malignancy of mammographic masses. Eye-tracking data and diagnostic decisions for 40 cases were acquired from four Radiology residents and two breast imaging experts as part of an IRB-approved pilot study. Gaze behavior features were extracted from the eye-tracking data. Computer-generated and BIRADS images features were extracted from the images. Finally, machine learning algorithms were used to merge gaze and image features for predicting human error. Feature selection was thoroughly explored to determine the relative contribution of the various features. Group-based and personalized user modeling was also investigated.Results: Machine learning can be used to predict diagnostic error by merging gaze behavior characteristics from the radiologist and textural characteristics from the image under review. Leveraging data collected from multiple readers produced a reasonable group model [area under the ROC curve (AUC) = 0.792 ± 0.030]. Personalized user modeling was far more accurate for the more experienced readers (AUC = 0.837 ± 0.029) than for the less experienced ones (AUC = 0.667 ± 0.099). The best performing group-based and personalized predictive models involved combinations of both gaze and image features.Conclusions: Diagnostic errors in mammography can be predicted to a good extent by leveraging the radiologists’ gaze behavior and image content.

  8. Predicting diagnostic error in Radiology via eye-tracking and image analytics: Application in mammography

    SciTech Connect

    Voisin, Sophie; Pinto, Frank M; Morin-Ducote, Garnetta; Hudson, Kathy; Tourassi, Georgia

    2013-01-01

    Purpose: The primary aim of the present study was to test the feasibility of predicting diagnostic errors in mammography by merging radiologists gaze behavior and image characteristics. A secondary aim was to investigate group-based and personalized predictive models for radiologists of variable experience levels. Methods: The study was performed for the clinical task of assessing the likelihood of malignancy of mammographic masses. Eye-tracking data and diagnostic decisions for 40 cases were acquired from 4 Radiology residents and 2 breast imaging experts as part of an IRB-approved pilot study. Gaze behavior features were extracted from the eye-tracking data. Computer-generated and BIRADs images features were extracted from the images. Finally, machine learning algorithms were used to merge gaze and image features for predicting human error. Feature selection was thoroughly explored to determine the relative contribution of the various features. Group-based and personalized user modeling was also investigated. Results: Diagnostic error can be predicted reliably by merging gaze behavior characteristics from the radiologist and textural characteristics from the image under review. Leveraging data collected from multiple readers produced a reasonable group model (AUC=0.79). Personalized user modeling was far more accurate for the more experienced readers (average AUC of 0.837 0.029) than for the less experienced ones (average AUC of 0.667 0.099). The best performing group-based and personalized predictive models involved combinations of both gaze and image features. Conclusions: Diagnostic errors in mammography can be predicted reliably by leveraging the radiologists gaze behavior and image content.

  9. Diagnostic imaging of the equine fetlock region using radiography and ultrasonography. Part 2: the bony disorders.

    PubMed

    Vanderperren, Katrien; Saunders, Jimmy H

    2009-08-01

    The metacarpophangeal/metatarsophalangeal (fetlock) joint in the horse is commonly associated with equine lameness and diagnostic imaging is routinely used to investigate disorders of the joint and its surrounding tissues. This review describes the osseous disorders of the fetlock as well as the technical aspects of taking radiographic and ultrasonographic images of the different lesions. In current clinical practice, a combination of radiography and ultrasonography is still the most frequently used approach to arrive at a diagnosis.

  10. Predicting diagnostic error in radiology via eye-tracking and image analytics: preliminary investigation in mammography.

    PubMed

    Voisin, Sophie; Pinto, Frank; Morin-Ducote, Garnetta; Hudson, Kathleen B; Tourassi, Georgia D

    2013-10-01

    The primary aim of the present study was to test the feasibility of predicting diagnostic errors in mammography by merging radiologists' gaze behavior and image characteristics. A secondary aim was to investigate group-based and personalized predictive models for radiologists of variable experience levels. The study was performed for the clinical task of assessing the likelihood of malignancy of mammographic masses. Eye-tracking data and diagnostic decisions for 40 cases were acquired from four Radiology residents and two breast imaging experts as part of an IRB-approved pilot study. Gaze behavior features were extracted from the eye-tracking data. Computer-generated and BIRADS images features were extracted from the images. Finally, machine learning algorithms were used to merge gaze and image features for predicting human error. Feature selection was thoroughly explored to determine the relative contribution of the various features. Group-based and personalized user modeling was also investigated. Machine learning can be used to predict diagnostic error by merging gaze behavior characteristics from the radiologist and textural characteristics from the image under review. Leveraging data collected from multiple readers produced a reasonable group model [area under the ROC curve (AUC) = 0.792 ± 0.030]. Personalized user modeling was far more accurate for the more experienced readers (AUC = 0.837 ± 0.029) than for the less experienced ones (AUC = 0.667 ± 0.099). The best performing group-based and personalized predictive models involved combinations of both gaze and image features. Diagnostic errors in mammography can be predicted to a good extent by leveraging the radiologists' gaze behavior and image content.