Posterior reversible encephalopathy with late postpartum eclampsia and short-term memory loss: a case report.

PubMed

Gimovsky, Martin L; Guzman, Guillermo M; Koscica, Karen L; Nazir, Munir A; Ross, Diane E

2010-01-01

Late postpartum eclampsia is more frequently recognized than past reports indicate. This report describes the association of a reversible encephalopathy in a woman with late postpartum eclampsia. A woman with lupus nephritis presented 7 days postpartum with eclampsia. Postseizure findings included dramatic short-term memory loss. Although a computed tomography scan was negative, subsequent magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) demonstrated vascular changes associated with a reversible encephalopathy. Conservative treatment with analeptic and antihypertensive therapy allowed a rapid resolution of all symptomatology. In women with eclampsia and unusual neurologic findings, an MRI/MRA may be useful even in the presence of a negative computed tomography scan.

Cryptococcus gattii Infection Presenting as an Aggressive Lung Mass.

PubMed

Zheng, Shuwei; Tan, Thuan Tong; Chien, Jaime Mei Fong

2018-06-01

Cryptococcus gattii is an endemic fungus predominantly isolated in the tropical and subtropical regions, causing predominantly pulmonary disease with a predilection for the central nervous system. Herein, we report a case of rapidly progressing C. gattii pneumonia in an immune-deficient but virologically suppressed host with underlying human immunodeficiency viral (HIV) infection, exhibiting various fungal morphologies from bronchoalveolar lavage (BAL) cytological specimens. A 51-year-old Chinese male with known HIV disease was admitted to the Singapore General Hospital for evaluation of functional decline, febrile episodes, and a left hilar mass on chest radiograph. Computed tomography (CT) showed consolidation in the apical segment of the left lower lobe. He underwent bronchoscopy and BAL. Positron emission tomography-computed tomography done 10 days after the initial CT showed approximate doubling of the pulmonary lesion. Cytological examination of the fluid revealed yeasts of varying sizes. Subsequent fungal culture from BAL fluid grew C. gattii 10 days later.

Computational adaptive optics for broadband optical interferometric tomography of biological tissue

NASA Astrophysics Data System (ADS)

Boppart, Stephen A.

2015-03-01

High-resolution real-time tomography of biological tissues is important for many areas of biological investigations and medical applications. Cellular level optical tomography, however, has been challenging because of the compromise between transverse imaging resolution and depth-of-field, the system and sample aberrations that may be present, and the low imaging sensitivity deep in scattering tissues. The use of computed optical imaging techniques has the potential to address several of these long-standing limitations and challenges. Two related techniques are interferometric synthetic aperture microscopy (ISAM) and computational adaptive optics (CAO). Through three-dimensional Fourierdomain resampling, in combination with high-speed OCT, ISAM can be used to achieve high-resolution in vivo tomography with enhanced depth sensitivity over a depth-of-field extended by more than an order-of-magnitude, in realtime. Subsequently, aberration correction with CAO can be performed in a tomogram, rather than to the optical beam of a broadband optical interferometry system. Based on principles of Fourier optics, aberration correction with CAO is performed on a virtual pupil using Zernike polynomials, offering the potential to augment or even replace the more complicated and expensive adaptive optics hardware with algorithms implemented on a standard desktop computer. Interferometric tomographic reconstructions are characterized with tissue phantoms containing sub-resolution scattering particles, and in both ex vivo and in vivo biological tissue. This review will collectively establish the foundation for high-speed volumetric cellular-level optical interferometric tomography in living tissues.

Potential risk of alpha-glucosidase inhibitor administration in prostate cancer external radiotherapy by exceptional rectal gas production: a case report.

PubMed

Nishimura, Takuya; Yamazaki, Hideya; Iwama, Kazuki; Oota, Yoshitaka; Aibe, Norihiro; Nakamura, Satoaki; Yoshida, Ken; Okabe, Haruumi; Yamada, Kei

2014-05-05

Radiotherapy is a standard treatment for prostate cancer, and image-guided radiotherapy is increasingly being used to aid precision of dose delivery to targeted tissues. However, precision during radiotherapy cannot be maintained when unexpected intrafraction organ motion occurs. We report our experience of internal organ motion caused by persistent gas production in a patient taking an alpha-glucosidase inhibitor. A 68-year-old Japanese man with prostate cancer visited our institution for treatment with helical tomotherapy. He suffered from diabetes mellitus and took an alpha-glucosidase inhibitor. Routine treatment planning computed tomography showed a large volume of rectal gas; an enema was given to void the rectum. Subsequent treatment planning computed tomography again showed a large volume of gas. After exercise (walking) to remove the intestinal gas, a third scan was performed as a test scan without tight fixation, which showed a sufficiently empty rectum for planning. However, after only a few minutes, treatment planning computed tomography again showed extreme accumulation of gas. Therefore, we postponed treatment planning computed tomography and consulted his doctor to suspend the alpha-glucosidase inhibitor, which was the expected cause of his persistent gas. Four days after the alpha-glucosidase inhibitor regimen was suspended, we took a fourth treatment planning computed tomography and made a treatment plan without gas accumulation. Thereafter, the absence of rectal gas accumulation was confirmed using daily megavolt computed tomography before treatment, and the patient received 37 fractions of intensity-modified radiotherapy at 74 Gy without rectal gas complications. In this case study, the alpha-glucosidase inhibitor induced the accumulation of intestinal gas, which may have caused unexpected organ motion, untoward reactions, and insufficient doses to clinical targets. We suggest that patients who are taking an alpha-glucosidase inhibitor for diabetes should discontinue use of that particular medicine prior to beginning radiotherapy.

Sherlock Holmes in the ER (the case of red and the head).

PubMed

Bendo, Edlira; Gilbert, Molly; Chavis, Pamela; Mistr, Susannah

2009-01-01

A 58-year-old woman presented with a problem with her peripheral vision. Computed tomography scan showed an occipital hemorrhagic stroke. She subsequently suffered gastrointestinal bleeding and at surgery biopsy of a portion of the middle colic artery aneurysm revealed changes consistent with polyarteritis nodosa.

Video-assisted thoracoscopic surgery for pulmonary nodules after computed tomography-guided marking with a spiral wire.

PubMed

Eichfeld, Uwe; Dietrich, Arne; Ott, Rudolph; Kloeppel, Rainer

2005-01-01

Peripheral pulmonary nodules are preferably removed by minimally invasive techniques, such as video-assisted thoracoscopic (VATS) surgery. These nodules should be marked preoperatively for better intraoperative detection and removal. Twenty-two cases with a single pulmonary nodule requiring surgical removal for histologic examination were included in a prospective study. Guided by computed tomography, nodules were marked preoperatively using a laser marker system and fixed with a spiral wire. The marked nodules were removed by VATS surgery immediately after the marking. The marking wire was placed in all 22 patients without any complications. The marked nodule was completely removed by VATS surgery in 19 patients. Conversion to thoracotomy was necessary in 3 patients, twice because of thoracoscopy-related problems and once because of a marking failure. The average times for the marking procedure and operation were 24 minutes and 32 minutes, respectively. This new method of computed tomography-guided nodule marking with a spiral wire and subsequent VATS surgery is very efficient in terms of localization and stable fixation of subpleural pulmonary nodules.

Anatomical Confirmation of Computed Tomography-Based Diagnosis of the Atherosclerosis Discovered in 17th Century Korean Mummy

PubMed Central

Kim, Myeung Ju; Kim, Yi-Suk; Oh, Chang Seok; Go, Jai-Hyang; Lee, In Sun; Park, Won-Kyu; Cho, Seok-Min; Kim, Soon-Kwan; Shin, Dong Hoon

2015-01-01

In the present study on a newly discovered 17th century Korean mummy, computed tomography (CT) revealed multiple aortic calcifications within the aortic wall that were indicative of ancient atherosclerosis. The CT-based findings were confirmed by our subsequent post-factum dissection, which exhibited possible signs of the disease including ulcerated plaques, ruptured hemorrhages, and intimal thickening where the necrotic core was covered by the fibrous cap. These findings are strong indicators that the mummy suffered from aortic atherosclerosis during her lifetime. The present study is a good example of how CT images of vascular calcifications can be a useful diagnostic tool in forming at least preliminary diagnoses of ancient atherosclerosis. PMID:25816014

Reduced ventilation-perfusion (V/Q) mismatch following endobronchial valve insertion demonstrated by Gallium-68 V/Q photon emission tomography/computed tomography.

PubMed

Leong, Paul; Le Roux, Pierre-Yves; Callahan, Jason; Siva, Shankar; Hofman, Michael S; Steinfort, Daniel P

2017-09-01

Endobronchial valves (EBVs) are increasingly deployed in the management of severe emphysema. Initial studies focussed on volume reduction as the mechanism, with subsequent improvement in forced expiratory volume in 1 s (FEV 1 ). More recent studies have emphasized importance of perfusion on predicting outcomes, though findings have been inconsistent. Gallium-68 ventilation-perfusion (V/Q) photon emission tomography (PET)/computed tomography (CT) is a novel imaging modality with advantages in spatial resolution, quantitation, and speed over conventional V/Q scintigraphy. We report a pilot case in which V/Q-PET/CT demonstrated discordant findings compared with quantitative CT analysis, and directed left lower lobe EBV placement. The patient experienced a significant improvement in 6-min walk distance (6MWD) without change in spirometry. Post-EBV V/Q-PET/CT demonstrated a marked decrease in unmatched (detrimental) V/Q areas and improvement in overall V/Q matching on post-EBV V/Q-PET/CT. These preliminary novel findings suggest that EBVs improve V/Q matching and may explain the observed functional improvements.

Using synchrotron X-ray phase-contrast micro-computed tomography to study tissue damage by laser irradiation.

PubMed

Robinson, Alan M; Stock, Stuart R; Soriano, Carmen; Xiao, Xianghui; Richter, Claus-Peter

2016-11-01

The aim of this study was to determine if X-ray micro-computed tomography could be used to locate and characterize tissue damage caused by laser irradiation and to describe its advantages over classical histology for this application. A surgical CO 2 laser, operated in single pulse mode (100 milliseconds) at different power settings, was used to ablate different types of cadaveric animal tissues. Tissue samples were then harvested and imaged with synchrotron X-ray phase-contrast and micro-computed tomography to generate stacks of virtual sections of the tissues. Subsequently, Fiji (ImageJ) software was used to locate tissue damage, then to quantify volumes of laser ablation cones and thermal coagulation damage from 3D renderings of tissue image stacks. Visual comparisons of tissue structures in X-ray images with those visible by classic light microscopy histology were made. We demonstrated that micro-computed tomography could be used to rapidly identify areas of surgical laser ablation, vacuolization, carbonization, and thermally coagulated tissue. Quantification and comparison of the ablation crater, which represents the volume of ablated tissue, and the thermal coagulation zone volumes were performed faster than we could by classical histology. We demonstrated that these procedures can be performed on fresh hydrated and non-sectioned plastic embedded tissue. We demonstrated that the application of non-destructive micro-computed tomography to the visualization and analysis of laser induced tissue damage without tissue sectioning is possible. This will improve evaluation of new surgical lasers and their corresponding effect on tissues. Lasers Surg. Med. 48:866-877, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Renal Manifestation of Birt-Hogg-Dubé Syndrome Depicted by 18F-fludeoxyglucose Positron Emission Tomography/Computed Tomography in a Patient with Hurtle Cell Thyroid Malignancy.

PubMed

Panagiotidis, Emmanouil; Seshadri, Nagabhushan; Vinjamuri, Sobhan

2018-01-01

Birt-Hogg-Dubé (BHD) syndrome is an autosomal dominant genetic disorder characterized by small papular skin lesions (fibrofolliculomas) causing susceptibility to kidney cancer, renal and pulmonary cysts, spontaneous pneumothoraces, and several noncutaneous tumors. We report a case of a 67-year-old woman, with a previous history of right hemithyroidectomy for adenomatous lesion. She presented with a swelling in the right thyroid bed that on subsequent biopsy revealed features of metastatic carcinoma. 18F-fludeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) performed for the detection of primary malignancy showed increased high-grade metabolic activity in the right supraclavicular soft tissue mass extending into the superior mediastinum. Moreover, on low-dose CT, there have been bilateral renal interpolar cortical lesions with mild metabolic activity. Given the fact that the right neck mass was highly unlikely to represent renal metastases in the absence of widespread metastatic disease, surgical excision of the right neck mass was performed. The histology of the mass was in keeping with hurtle cell thyroid carcinoma. In regard to renal lesions, bilateral partial nephrectomy was performed, which was consistent with chromophobe renal cell carcinoma, raising the suspicion of BHD that was confirmed by the subsequent genetic evaluation. It is well established that 18F-FDG PET/CT study is not an optimal modality for evaluation of renal lesions. However, careful assessment of the CT features in conjunction with the associated metabolic activity of the 18F-FDG PET component increases the diagnostic accuracy of PET/CT.

The effect on cadaver blood DNA identification by the use of targeted and whole body post-mortem computed tomography angiography.

PubMed

Rutty, Guy N; Barber, Jade; Amoroso, Jasmin; Morgan, Bruno; Graham, Eleanor A M

2013-12-01

Post-mortem computed tomography angiography (PMCTA) involves the injection of contrast agents. This could have both a dilution effect on biological fluid samples and could affect subsequent post-contrast analytical laboratory processes. We undertook a small sample study of 10 targeted and 10 whole body PMCTA cases to consider whether or not these two methods of PMCTA could affect post-PMCTA cadaver blood based DNA identification. We used standard methodology to examine DNA from blood samples obtained before and after the PMCTA procedure. We illustrate that neither of these PMCTA methods had an effect on the alleles called following short tandem repeat based DNA profiling, and therefore the ability to undertake post-PMCTA blood based DNA identification.

The diagnostic value of single-photon emission computed tomography/computed tomography for severe sacroiliac joint dysfunction.

PubMed

Tofuku, Katsuhiro; Koga, Hiroaki; Komiya, Setsuro

2015-04-01

We aimed to evaluate the value of single-photon emission computed tomography (SPECT)/computed tomography (CT) for the diagnosis of sacroiliac joint (SIJ) dysfunction. SPECT/CT was performed in 32 patients with severe SIJ dysfunction, who did not respond to 1-year conservative treatment and had a score of >4 points on a 10-cm visual analog scale. We investigated the relationship between the presence of severe SIJ dysfunction and tracer accumulation, as confirmed by SPECT/CT. In cases of bilateral SIJ dysfunction, we also compared the intensity of tracer accumulation on each side. Moreover, we examined the relationship between the intensity of tracer accumulation and the different treatments the patients subsequently received. All 32 patients with severe SIJ dysfunction had tracer accumulation with a standardized uptake value (SUV) of >2.2 (mean SUV 4.7). In the 19 patients with lateralized symptom intensity, mean SUVs of the dominant side were significantly higher than those of the nondominant side. In 10 patients with no lateralization, the difference in the SUVs between sides was <0.6. Patients exhibiting higher levels of tracer accumulation required more advanced treatment. Patients with higher levels of tracer accumulation had greater symptom severity and also required more advanced treatment. Thus, we believe that SPECT/CT may be a suitable supplementary diagnostic modality for SIJ dysfunction as well as a useful technique for predicting the prognosis of this condition.

An Investigation of the Morphology of the Petrotympanic Fissure Using Cone-Beam Computed Tomography

PubMed Central

Syriopoulos, Konstantinos; Sens, Rogier L.; Politis, Constantinus

2018-01-01

ABSTRACT Objectives The purpose of the present study was: a) to examine the visibility and morphology of the petrotympanic fissure on cone-beam computed tomography images, and b) to investigate whether the petrotympanic fissure morphology is significantly affected by gender and age, or not. Material and Methods Using Newtom VGi (QR Verona, Italy), 106 cone-beam computed tomography examinations (212 temporomandibular joint areas) of both genders were retrospectively and randomly selected. Two observers examined the images and subsequently classified by consensus the petrotympanic fissure morphology into the following three types: type 1 - widely open; type 2 - narrow middle; type 3 - very narrow/closed. Results The petrotympanic fissure morphology was assessed as type 1, type 2, and type 3 in 85 (40.1%), 72 (34.0%), and 55 (25.9%) cases, respectively. No significant difference was found between left and right petrotympanic fissure morphology (Kappa = 0.37; P < 0.001). Furthermore, no significant difference was found between genders, specifically P = 0.264 and P = 0.211 for the right and left petrotympanic fissure morphology, respectively. However, the ordinal logistic regression analysis showed that males tend to have narrower petrotympanic fissures, in particular OR = 1.58 for right and OR = 1.5 for left petrotympanic fissure. Conclusions The current study lends support to the conclusion that an enhanced multi-planar cone-beam computed tomography yields a clear depiction of the petrotympanic fissure's morphological characteristics. We have found that the morphology is neither gender nor age-related. PMID:29707183

An Investigation of the Morphology of the Petrotympanic Fissure Using Cone-Beam Computed Tomography.

PubMed

Damaskos, Spyros; Syriopoulos, Konstantinos; Sens, Rogier L; Politis, Constantinus

2018-01-01

The purpose of the present study was: a) to examine the visibility and morphology of the petrotympanic fissure on cone-beam computed tomography images, and b) to investigate whether the petrotympanic fissure morphology is significantly affected by gender and age, or not. Using Newtom VGi (QR Verona, Italy), 106 cone-beam computed tomography examinations (212 temporomandibular joint areas) of both genders were retrospectively and randomly selected. Two observers examined the images and subsequently classified by consensus the petrotympanic fissure morphology into the following three types: type 1 - widely open; type 2 - narrow middle; type 3 - very narrow/closed. The petrotympanic fissure morphology was assessed as type 1, type 2, and type 3 in 85 (40.1%), 72 (34.0%), and 55 (25.9%) cases, respectively. No significant difference was found between left and right petrotympanic fissure morphology (Kappa = 0.37; P < 0.001). Furthermore, no significant difference was found between genders, specifically P = 0.264 and P = 0.211 for the right and left petrotympanic fissure morphology, respectively. However, the ordinal logistic regression analysis showed that males tend to have narrower petrotympanic fissures, in particular OR = 1.58 for right and OR = 1.5 for left petrotympanic fissure. The current study lends support to the conclusion that an enhanced multi-planar cone-beam computed tomography yields a clear depiction of the petrotympanic fissure's morphological characteristics. We have found that the morphology is neither gender nor age-related.

Rationale and design of the dual-energy computed tomography for ischemia determination compared to "gold standard" non-invasive and invasive techniques (DECIDE-Gold): A multicenter international efficacy diagnostic study of rest-stress dual-energy computed tomography angiography with perfusion.

PubMed

Truong, Quynh A; Knaapen, Paul; Pontone, Gianluca; Andreini, Daniele; Leipsic, Jonathon; Carrascosa, Patricia; Lu, Bin; Branch, Kelley; Raman, Subha; Bloom, Stephen; Min, James K

2015-10-01

Dual-energy CT (DECT) has potential to improve myocardial perfusion for physiologic assessment of coronary artery disease (CAD). Diagnostic performance of rest-stress DECT perfusion (DECTP) is unknown. DECIDE-Gold is a prospective multicenter study to evaluate the accuracy of DECT to detect hemodynamic (HD) significant CAD, as compared to fractional flow reserve (FFR) as a reference standard. Eligible participants are subjects with symptoms of CAD referred for invasive coronary angiography (ICA). Participants will undergo DECTP, which will be performed by pharmacological stress, and participants will subsequently proceed to ICA and FFR. HD-significant CAD will be defined as FFR ≤ 0.80. In those undergoing myocardial stress imaging (MPI) by positron emission tomography (PET), single photon emission computed tomography (SPECT) or cardiac magnetic resonance (CMR) imaging, ischemia will be graded by % ischemic myocardium. Blinded core laboratory interpretation will be performed for CCTA, DECTP, MPI, ICA, and FFR. Primary endpoint is accuracy of DECTP to detect ≥1 HD-significant stenosis at the subject level when compared to FFR. Secondary and tertiary endpoints are accuracies of combinations of DECTP at the subject and vessel levels compared to FFR and MPI. DECIDE-Gold will determine the performance of DECTP for diagnosing ischemia.

Natural History of Ground-Glass Lesions Among Patients With Previous Lung Cancer.

PubMed

Shewale, Jitesh B; Nelson, David B; Rice, David C; Sepesi, Boris; Hofstetter, Wayne L; Mehran, Reza J; Vaporciyan, Ara A; Walsh, Garrett L; Swisher, Stephen G; Roth, Jack A; Antonoff, Mara B

2018-06-01

Among patients with previous lung cancer, the malignant potential of subsequent ground-glass opacities (GGOs) on computed tomography remains unknown, with a lack of consensus regarding surveillance and intervention. This study sought to describe the natural history of GGO in patients with a history of lung cancer. A retrospective review was performed of 210 patients with a history of lung cancer and ensuing computed tomography evidence of pure or mixed GGOs between 2007 and 2013. Computed tomography reports were reviewed to determine the fate of the GGOs, by classifying all lesions as stable, resolved, or progressive over the course of the study. Multivariable analysis was performed to identify predictors of GGO progression and resolution. The mean follow-up time was 13 months. During this period, 55 (26%) patients' GGOs were stable, 131 (62%) resolved, and 24 (11%) progressed. Of the 24 GGOs that progressed, three were subsequently diagnosed as adenocarcinoma. Patients of black race (odds ratio [OR], 0.26) and other races besides white (OR, 0.89) had smaller odds of GGO resolution (p = 0.033), whereas patients with previous lung squamous cell carcinoma (OR, 5.16) or small cell carcinoma (OR, 5.36) were more likely to experience GGO resolution (p < 0.001). On multivariable analysis, only a history of adenocarcinoma was an independent predictor of GGO progression (OR, 6.9; p = 0.011). Among patients with a history of lung cancer, prior adenocarcinoma emerged as a predictor of GGO progression, whereas a history of squamous cell carcinoma or small cell carcinoma and white race were identified as predictors of GGO resolution. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Evaluation of prosthetic valve thrombosis by 64-row multi-detector computed tomography. .

PubMed

Tarzia, Vincenzo; Bortolussi, Giacomo; Rubino, Maurizio; Gallo, Michele; Bottio, Tomaso; Gerosa, Gino

2015-03-01

Multi-detector computed tomography (MDCT), combined with retrospective electrocardiographic gating, permits cardiac imaging with high accuracy. Recent advances in MDCT have seemed to respond adequately to the need for a non-invasive and reliable assessment of the coronary artery lumen. Two patients with prosthetic aortic valves (one bioprosthetic, one mechanical) presented at the authors' institution with dyspnea and syncopal episodes. MDCT was performed to evaluate thrombus characteristics and exclude coronary artery disease (CAD). Based on the MDCT coronary artery assessment, neither patient underwent preoperative invasive coronary angiography, abolishing the risk of any iatrogenic thrombus fragmentation and subsequent embolization. One patient underwent surgical treatment without complications, while medical therapy was successful in the other case. MDCT can be used for the accurate imaging of thrombi on prosthetic aortic valves, and to correctly assess possible CAD.

The effect on toxicology, biochemistry and immunology investigations by the use of targeted post-mortem computed tomography angiography.

PubMed

Rutty, G N; Smith, P; Visser, T; Barber, J; Amorosa, J; Morgan, B

2013-02-10

It is recognised in autopsy practice that investigations such as toxicology can be affected by post-mortem change. Post-mortem computed tomography angiography (PMCT-A) involves the injection of contrast agents. This could cause dilution of a biological fluid sample or cause the circulation of blood after death by mechanical pumping, and thus has the potential to affect laboratory investigations. We undertook a small sample study to consider whether targeted PMCT-A had any significant effect on subsequent samples taken for biochemical, toxicological or immunological investigations. Although the results of our study do illustrate differences between the pre and post PMCT-A results, these differences are considered not to be of diagnostic significance and not due to the direct effect of targeted PMCT-A. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Prediction of Blood-Brain Barrier Disruption and Intracerebral Hemorrhagic Infarction Using Arterial Spin-Labeling Magnetic Resonance Imaging.

PubMed

Niibo, Takeya; Ohta, Hajime; Miyata, Shirou; Ikushima, Ichiro; Yonenaga, Kazuchika; Takeshima, Hideo

2017-01-01

Arterial spin-labeling magnetic resonance imaging is sensitive for detecting hyperemic lesions (HLs) in patients with acute ischemic stroke. We evaluated whether HLs could predict blood-brain barrier (BBB) disruption and hemorrhagic transformation (HT) in acute ischemic stroke patients. In a retrospective study, arterial spin-labeling was performed within 6 hours of symptom onset before revascularization treatment in 25 patients with anterior circulation large vessel occlusion on baseline magnetic resonance angiography. All patients underwent angiographic procedures intended for endovascular therapy and a noncontrast computed tomography scan immediately after treatment. BBB disruption was defined as a hyperdense lesion present on the posttreatment computed tomography scan. A subacute magnetic resonance imaging or computed tomography scan was performed during the subacute phase to assess HTs. The relationship between HLs and BBB disruption and HT was examined using the Alberta Stroke Program Early Computed Tomography Score locations in the symptomatic hemispheres. A HL was defined as a region where CBF relative ≥1.4 (CBF relative =CBF HL /CBF contralateral ). HLs, BBB disruption, and HT were found in 9, 15, and 15 patients, respectively. Compared with the patients without HLs, the patients with HLs had a higher incidence of both BBB disruption (100% versus 37.5%; P=0.003) and HT (100% versus 37.5%; P=0.003). Based on the Alberta Stroke Program Early Computed Tomography Score locations, 21 regions of interests displayed HLs. Compared with the regions of interests without HLs, the regions of interests with HLs had a higher incidence of both BBB disruption (42.8% versus 3.9%; P<0.001) and HT (85.7% versus 7.8%; P<0.001). HLs detected on pretreatment arterial spin-labeling maps may enable the prediction and localization of subsequent BBB disruption and HT. © 2016 American Heart Association, Inc.

Validation of the Australian diagnostic reference levels for paediatric multi detector computed tomography: a comparison of RANZCR QUDI data and subsequent NDRLS data from 2012 to 2015.

PubMed

Anna, Hayton; Wallace, Anthony; Thomas, Peter

2017-03-01

The national diagnostic reference level service (NDRLS), was launched in 2011, however no paediatric data were submitted during the first calendar year of operation. As such, Australian national diagnostic reference levels (DRLs), for paediatric multi detector computed tomography (MDCT), were established using data obtained from a Royal Australian and New Zealand College of Radiologists (RANZCR), Quality Use of Diagnostic Imaging (QUDI), study. Paediatric data were submitted to the NDRLS in 2012 through 2015. An analysis has been made of the NDRLS paediatric data using the same method as was used to analyse the QUDI data to establish the Australian national paediatric DRLs for MDCT. An analysis of the paediatric NDRLS data has also been made using the method used to calculate the Australian national adult DRLs for MDCT. A comparison between the QUDI data and subsequent NDRLS data shows the NDRLS data to be lower on average for the Head and AbdoPelvis protocol and similar for the chest protocol. Using an average of NDRLS data submitted between 2012 and 2015 implications for updated paediatric DRLS are considered.

X-ray micro computed tomography for the visualization of an atherosclerotic human coronary artery

NASA Astrophysics Data System (ADS)

Matviykiv, Sofiya; Buscema, Marzia; Deyhle, Hans; Pfohl, Thomas; Zumbuehl, Andreas; Saxer, Till; Müller, Bert

2017-06-01

Atherosclerosis refers to narrowing or blocking of blood vessels that can lead to a heart attack, chest pain or stroke. Constricted segments of diseased arteries exhibit considerably increased wall shear stress, compared to the healthy ones. One of the possibilities to improve patient’s treatment is the application of nano-therapeutic approaches, based on shear stress sensitive nano-containers. In order to tailor the chemical composition and subsequent physical properties of such liposomes, one has to know precisely the morphology of critically stenosed arteries at micrometre resolution. It is often obtained by means of histology, which has the drawback of offering only two-dimensional information. Additionally, it requires the artery to be decalcified before sectioning, which might lead to deformations within the tissue. Micro computed tomography (μCT) enables the three-dimensional (3D) visualization of soft and hard tissues at micrometre level. μCT allows lumen segmentation that is crucial for subsequent flow simulation analysis. In this communication, tomographic images of a human coronary artery before and after decalcification are qualitatively and quantitatively compared. We analyse the cross section of the diseased human coronary artery before and after decalcification, and calculate the lumen area of both samples.

Positron Emission Tomography - Computed Tomography (PET/CT)

MedlinePlus

... A-Z Positron Emission Tomography - Computed Tomography (PET/CT) Positron emission tomography (PET) uses small amounts of ... What is Positron Emission Tomography – Computed Tomography (PET/CT) Scanning? Positron emission tomography, also called PET imaging ...

Limitations of PET/CT in the Detection of Occult N1 Metastasis in Clinical Stage I(T1-2aN0) Non-Small Cell Lung Cancer for Staging Prior to Stereotactic Body Radiotherapy

PubMed Central

Akthar, Adil S.; Ferguson, Mark K.; Koshy, Matthew; Vigneswaran, Wickii T.

2016-01-01

Purpose/Objectives: Patients receiving stereotactic body radiotherapy for stage I non-small cell lung cancer are typically staged clinically with positron emission tomography–computed tomography. Currently, limited data exist for the detection of occult hilar/peribronchial (N1) disease. We hypothesize that positron emission tomography–computed tomography underestimates spread of cancer to N1 lymph nodes and that future stereotactic body radiotherapy patients may benefit from increased pathologic evaluation of N1 nodal stations in addition to N2 nodes. Materials/Methods: A retrospective study was performed of all patients with clinical stage I (T1-2aN0) non-small cell lung cancer (American Joint Committee on Cancer, 7th edition) by positron emission tomography–computed tomography at our institution from 2003 to 2011, with subsequent surgical resection and lymph node staging. Findings on positron emission tomography–computed tomography were compared to pathologic nodal involvement to determine the negative predictive value of positron emission tomography–computed tomography for the detection of N1 nodal disease. An analysis was conducted to identify predictors of occult spread. Results: A total of 105 patients with clinical stage I non-small cell lung cancer were included in this study, of which 8 (7.6%) patients were found to have occult N1 metastasis on pathologic review yielding a negative predictive value for N1 disease of 92.4%. No patients had occult mediastinal nodes. The negative predictive value for positron emission tomography–computed tomography in patients with clinical stage T1 versus T2 tumors was 72 (96%) of 75 versus 25 (83%) of 30, respectively (P = .03), and for peripheral versus central tumor location was 77 (98%) of 78 versus 20 (74%) of 27, respectively (P = .0001). The negative predictive values for peripheral T1 and T2 tumors were 98% and 100%, respectively; while for central T1 and T2 tumors, the rates were 85% and 64%, respectively. Occult lymph node involvement was not associated with primary tumor maximum standard uptake value, histology, grade, or interval between positron emission tomography–computed tomography and surgery. Conclusion: Our results support pathologic assessment of N1 lymph nodes in patients with stage Inon-small cell lung cancer considered for stereotactic body radiotherapy, with the greatest benefit in patients with central and T2 tumors. Diagnostic evaluation with endoscopic bronchial ultrasound should be considered in the evaluation of stereotactic body radiotherapy candidates. PMID:26792491

Prevalence of incidental pulmonary nodules on computed tomography of the thorax in trauma patients.

PubMed

Hammerschlag, G; Cao, J; Gumm, K; Irving, L; Steinfort, D

2015-06-01

Lung cancer is the third leading cause of death in high-income countries. Early detection leads to improved clinical outcomes, with evidence showing that lung cancer screening reduces lung cancer mortality. Knowledge of the population prevalence of pulmonary nodules affects the efficacy and cost-effectiveness of a local screening programme. We performed a retrospective review of our trauma database looking for the prevalence of incidental pulmonary nodules on computed tomography of the thorax. Prevalence of nodules and follow up according to Fleischner Guidelines were reviewed. Two hundred and forty-eight patients underwent a computed tomography thorax as part of their trauma assessment. 8.5% (21/248) had incidental pulmonary nodules. Eighty-one per cent of these (17/21) required follow up according to the Fleischner Society Guidelines. One was subsequently diagnosed with primary lung cancer, one with metastatic sigmoid cancer and one with invasive aspergillus. Incidental pulmonary nodules are common in the general population. This has implications for possible lung cancer screening recommendations in the Australian population. Referral and/or review systems are essential to ensure adequate follow up of incidental findings, as it is likely some patients are not receiving adequate follow up at present. © 2015 Royal Australasian College of Physicians.

[Diagnostic imaging of changes of the canine intervertebral disc].

PubMed

Harder, Lisa K

2016-10-12

Intervertebral disc degeneration can cause intervertebral disc herniation. Diagnostic imaging, including radiography, computed tomography and magnetic resonance imaging, is the most important tool in diagnosis. Firstly, an overview of macroscopic and biochemical physiology and pathology of the intervertebral disc will be given. Subsequently, the physics of diagnostic imaging and the appearance of intervertebral disc degeneration and displacement in several imaging methods are described.

Image interpolation allows accurate quantitative bone morphometry in registered micro-computed tomography scans.

PubMed

Schulte, Friederike A; Lambers, Floor M; Mueller, Thomas L; Stauber, Martin; Müller, Ralph

2014-04-01

Time-lapsed in vivo micro-computed tomography is a powerful tool to analyse longitudinal changes in the bone micro-architecture. Registration can overcome problems associated with spatial misalignment between scans; however, it requires image interpolation which might affect the outcome of a subsequent bone morphometric analysis. The impact of the interpolation error itself, though, has not been quantified to date. Therefore, the purpose of this ex vivo study was to elaborate the effect of different interpolator schemes [nearest neighbour, tri-linear and B-spline (BSP)] on bone morphometric indices. None of the interpolator schemes led to significant differences between interpolated and non-interpolated images, with the lowest interpolation error found for BSPs (1.4%). Furthermore, depending on the interpolator, the processing order of registration, Gaussian filtration and binarisation played a role. Independent from the interpolator, the present findings suggest that the evaluation of bone morphometry should be done with images registered using greyscale information.

The role of mobile computed tomography in mass fatality incidents.

PubMed

Rutty, Guy N; Robinson, Claire E; BouHaidar, Ralph; Jeffery, Amanda J; Morgan, Bruno

2007-11-01

Mobile multi-detector computed tomography (MDCT) scanners are potentially available to temporary mortuaries and can be operational within 20 min of arrival. We describe, to our knowledge, the first use of mobile MDCT for a mass fatality incident. A mobile MDCT scanner attended the disaster mortuary after a five vehicle road traffic incident. Five out of six bodies were successfully imaged by MDCT in c. 15 min per body. Subsequent full radiological analysis took c. 1 h per case. The results were compared to the autopsy examinations. We discuss the advantages and disadvantages of imaging with mobile MDCT in relation to mass fatality work, illustrating the body pathway process, and its role in the identification of the pathology, personal effects, and health and safety hazards. We propose that the adoption of a single modality of mobile MDCT could replace the current use of multiple radiological sources within a mass fatality mortuary.

The benefits of the Atlas of Human Cardiac Anatomy website for the design of cardiac devices.

PubMed

Spencer, Julianne H; Quill, Jason L; Bateman, Michael G; Eggen, Michael D; Howard, Stephen A; Goff, Ryan P; Howard, Brian T; Quallich, Stephen G; Iaizzo, Paul A

2013-11-01

This paper describes how the Atlas of Human Cardiac Anatomy website can be used to improve cardiac device design throughout the process of development. The Atlas is a free-access website featuring novel images of both functional and fixed human cardiac anatomy from over 250 human heart specimens. This website provides numerous educational tutorials on anatomy, physiology and various imaging modalities. For instance, the 'device tutorial' provides examples of devices that were either present at the time of in vitro reanimation or were subsequently delivered, including leads, catheters, valves, annuloplasty rings and stents. Another section of the website displays 3D models of the vasculature, blood volumes and/or tissue volumes reconstructed from computed tomography and magnetic resonance images of various heart specimens. The website shares library images, video clips and computed tomography and MRI DICOM files in honor of the generous gifts received from donors and their families.

Endoscopic bronchial occlusion for postoperative persistent bronchopleural fistula with computed tomography fluoroscopy guidance and virtual bronchoscopic navigation

PubMed Central

Yanagiya, Masahiro; Matsumoto, Jun; Nagano, Masaaki; Kusakabe, Masashi; Matsumoto, Yoko; Furukawa, Ryutaro; Ohara, Sayaka; Usui, Kazuhiro

2018-01-01

Abstract Rationale: The development of postoperative bronchopleural fistula (BPF) remains a challenge in thoracic surgery. We herein report a case of BPF successfully treated with endoscopic bronchial occlusion under computed tomography (CT) fluoroscopy and virtual bronchoscopic navigation (VBN). Patient concerns: A 63-year-old man underwent right upper lobectomy with concomitant S6a subsegmentectomy for lung adenocarcinoma. On postoperative day 24, he complained of shaking chills with high fever. Diagnoses: BPF with subsequent pneumonia and empyema. Interventions: Despite aggressive surgical interventions for the BPF, air leakage persisted postoperatively. On days 26 and 34 after the final operation, endobronchial occlusions were performed under CT fluoroscopy and VBN. Outcomes: The air leaks greatly decreased and the patient was discharged. Lessons: CT fluoroscopy and VBN can be useful techniques for endobronchial occlusion in the treatment of BPF. PMID:29443771

Facial soft-tissue asymmetry in three-dimensional cone-beam computed tomography images of children with surgically corrected unilateral clefts.

PubMed

Starbuck, John Marlow; Ghoneima, Ahmed; Kula, Katherine

2014-03-01

Cleft lip with or without cleft palate (CL/P) is a relatively common craniofacial malformation involving bony and soft-tissue disruptions of the nasolabial and dentoalveolar regions. The combination of CL/P and subsequent craniofacial surgeries to close the cleft and improve appearance of the cutaneous upper lip and nose can cause scarring and muscle pull, possibly resulting in soft-tissue depth asymmetries across the face. We tested the hypothesis that tissue depths in children with unilateral CL/P exhibit differences in symmetry across the sides of the face. Twenty-eight tissue depths were measured on cone-beam computed tomography images of children with unilateral CL/P (n = 55), aged 7 to 17 years, using Dolphin software (version 11.5). Significant differences in tissue depth symmetry were found around the cutaneous upper lip and nose in patients with unilateral CL/P.

CAC-DRS: Coronary Artery Calcium Data and Reporting System. An expert consensus document of the Society of Cardiovascular Computed Tomography (SCCT).

PubMed

Hecht, Harvey S; Blaha, Michael J; Kazerooni, Ella A; Cury, Ricardo C; Budoff, Matt; Leipsic, Jonathon; Shaw, Leslee

2018-03-30

The goal of CAC-DRS: Coronary Artery Calcium Data and Reporting System is to create a standardized method to communicate findings of CAC scanning on all noncontrast CT scans, irrespective of the indication, in order to facilitate clinical decision-making, with recommendations for subsequent patient management. The CAC-DRS classification is applied on a per-patient basis and represents the total calcium score and the number of involved arteries. General recommendations are provided for further management of patients with different degrees of calcified plaque burden based on CAC-DRS classification. In addition, CAC-DRS will provide a framework of standardization that may benefit quality assurance and tracking patient outcomes with the potential to ultimately result in improved quality of care. Copyright © 2018 Society of Cardiovascular Computed Tomography. All rights reserved.

X-ray computed tomography to study rice (Oryza sativa L.) panicle development

PubMed Central

Jhala, Vibhuti M.; Thaker, Vrinda S.

2015-01-01

Computational tomography is an important technique for developing digital agricultural models that may help farmers and breeders for increasing crop quality and yield. In the present study an attempt has been made to understand rice seed development within the panicle at different developmental stages using this technique. During the first phase of cell division the Hounsfield Unit (HU) value remained low, increased in the dry matter accumulation phase, and finally reached a maximum at the maturation stage. HU value and seed dry weight showed a linear relationship in the varieties studied. This relationship was confirmed subsequently using seven other varieties. This is therefore an easy, simple, and non-invasive technique which may help breeders to select the best varieties. In addition, it may also help farmers to optimize post-anthesis agronomic practices as well as deciding the crop harvest time for higher grain yield. PMID:26265763

SCCT guidelines on radiation dose and dose-optimization strategies in cardiovascular CT

PubMed Central

Halliburton, Sandra S.; Abbara, Suhny; Chen, Marcus Y.; Gentry, Ralph; Mahesh, Mahadevappa; Raff, Gilbert L.; Shaw, Leslee J.; Hausleiter, Jörg

2012-01-01

Over the last few years, computed tomography (CT) has developed into a standard clinical test for a variety of cardiovascular conditions. The emergence of cardiovascular CT during a period of dramatic increase in radiation exposure to the population from medical procedures and heightened concern about the subsequent potential cancer risk has led to intense scrutiny of the radiation burden of this new technique. This has hastened the development and implementation of dose reduction tools and prompted closer monitoring of patient dose. In an effort to aid the cardiovascular CT community in incorporating patient-centered radiation dose optimization and monitoring strategies into standard practice, the Society of Cardiovascular Computed Tomography has produced a guideline document to review available data and provide recommendations regarding interpretation of radiation dose indices and predictors of risk, appropriate use of scanner acquisition modes and settings, development of algorithms for dose optimization, and establishment of procedures for dose monitoring. PMID:21723512

Relationship between the Self-Rating Anxiety Scale score and the success rate of 64-slice computed tomography coronary angiography.

PubMed

Li, Hui; Jin, Dan; Qiao, Fang; Chen, Jianchang; Gong, Jianping

Computed tomography coronary angiography, a key method for obtaining coronary artery images, is widely used to screen for coronary artery diseases due to its noninvasive nature. In China, 64-slice computed tomography systems are now the most common models. As factors that directly affect computed tomography performance, heart rate and rhythm control are regulated by the autonomic nervous system and are highly related to the emotional state of the patient. The aim of this prospective study is to use a pre-computed tomography scan Self-Rating Anxiety Scale assessment to analyze the effects of tension and anxiety on computed tomography coronary angiography success. Subjects aged 18-85 years who were planned to undergo computed tomography coronary angiography were enrolled; 1 to 2 h before the computed tomography scan, basic patient data (gender, age, heart rate at rest, and family history) and Self-Rating Anxiety Scale score were obtained. The same group of imaging department doctors, technicians, and nurses performed computed tomography coronary angiography for all the enrolled subjects and observed whether those subjects could finish the computed tomography coronary angiography scan and provide clear, diagnostically valuable images. Participants were divided into successful (obtained diagnostically useful coronary images) and unsuccessful groups. Basic data and Self-Rating Anxiety Scale scores were compared between the groups. The Self-Rating Anxiety Scale standard score of the successful group was lower than that of the unsuccessful group (P = 0.001). As the Self-Rating Anxiety Scale standard score rose, the success rate of computed tomography coronary angiography decreased. The Self-Rating Anxiety Scale score has a negative relationship with computed tomography coronary angiography success. Anxiety can be a disadvantage in computed tomography coronary angiography examination. The pre-computed tomography coronary angiography scan Self-Rating Anxiety Scale score may be a useful tool for assessing whether a computed tomography coronary angiography scan will be successful or not. © The Author(s) 2015.

Beam hardening correction for interior tomography based on exponential formed model and radon inversion transform

NASA Astrophysics Data System (ADS)

Chen, Siyu; Zhang, Hanming; Li, Lei; Xi, Xiaoqi; Han, Yu; Yan, Bin

2016-10-01

X-ray computed tomography (CT) has been extensively applied in industrial non-destructive testing (NDT). However, in practical applications, the X-ray beam polychromaticity often results in beam hardening problems for image reconstruction. The beam hardening artifacts, which manifested as cupping, streaks and flares, not only debase the image quality, but also disturb the subsequent analyses. Unfortunately, conventional CT scanning requires that the scanned object is completely covered by the field of view (FOV), the state-of-art beam hardening correction methods only consider the ideal scanning configuration, and often suffer problems for interior tomography due to the projection truncation. Aiming at this problem, this paper proposed a beam hardening correction method based on radon inversion transform for interior tomography. Experimental results show that, compared to the conventional correction algorithms, the proposed approach has achieved excellent performance in both beam hardening artifacts reduction and truncation artifacts suppression. Therefore, the presented method has vitally theoretic and practicable meaning in artifacts correction of industrial CT.

Computed Tomography (CT) - Spine

MedlinePlus

... Resources Professions Site Index A-Z Computed Tomography (CT) - Spine Computed tomography (CT) of the spine is ... of CT Scanning of the Spine? What is CT Scanning of the Spine? Computed tomography, more commonly ...

Clinical value of whole body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of metastatic bladder cancer.

PubMed

Yang, Zhongyi; Pan, Lingling; Cheng, Jingyi; Hu, Silong; Xu, Junyan; Ye, Dingwei; Zhang, Yingjian

2012-07-01

To investigate the value of whole-body fluorine-18 2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography for the detection of metastatic bladder cancer. From December 2006 to August 2010, 60 bladder cancer patients (median age 60.5 years old, range 32-96) underwent whole body positron emission tomography/computed tomography positron emission tomography/computed tomography. The diagnostic accuracy was assessed by performing both organ-based and patient-based analyses. Identified lesions were further studied by biopsy or clinically followed for at least 6 months. One hundred and thirty-four suspicious lesions were identified. Among them, 4 primary cancers (2 pancreatic cancers, 1 colonic and 1 nasopharyngeal cancer) were incidentally detected, and the patients could be treated on time. For the remaining 130 lesions, positron emission tomography/computed tomography detected 118 true positive lesions (sensitivity = 95.9%). On the patient-based analysis, the overall sensitivity and specificity resulted to be 87.1% and 89.7%, respectively. There was no difference of sensitivity and specificity in patients with or without adjuvant treatment in terms of detection of metastatic sites by positron emission tomography/computed tomography. Compared with conventional imaging modality, positron emission tomography/computed tomography correctly changed the management in 15 patients (25.0%). Positron emission tomography/computed tomography has excellent sensitivity and specificity in the detection of metastatic bladder cancer and it provides additional diagnostic information compared to standard imaging techniques. © 2012 The Japanese Urological Association.

A novel PFIB sample preparation protocol for correlative 3D X-ray CNT and FIB-TOF-SIMS tomography.

PubMed

Priebe, Agnieszka; Audoit, Guillaume; Barnes, Jean-Paul

2017-02-01

We present a novel sample preparation method that allows correlative 3D X-ray Computed Nano-Tomography (CNT) and Focused Ion Beam Time-Of-Flight Secondary Ion Mass Spectrometry (FIB-TOF-SIMS) tomography to be performed on the same sample. In addition, our invention ensures that samples stay unmodified structurally and chemically between the subsequent experiments. The main principle is based on modifying the topography of the X-ray CNT experimental setup before FIB-TOF-SIMS measurements by incorporating a square washer around the sample. This affects the distribution of extraction field lines and therefore influences the trajectories of secondary ions that are now guided more efficiently towards the detector. As the result, secondary ion detection is significantly improved and higher, i.e. statistically better, signals are obtained. Copyright © 2016 Elsevier B.V. All rights reserved.

Iterative image reconstruction in elastic inhomogenous media with application to transcranial photoacoustic tomography

NASA Astrophysics Data System (ADS)

Poudel, Joemini; Matthews, Thomas P.; Mitsuhashi, Kenji; Garcia-Uribe, Alejandro; Wang, Lihong V.; Anastasio, Mark A.

2017-03-01

Photoacoustic computed tomography (PACT) is an emerging computed imaging modality that exploits optical contrast and ultrasonic detection principles to form images of the photoacoustically induced initial pressure distribution within tissue. The PACT reconstruction problem corresponds to a time-domain inverse source problem, where the initial pressure distribution is recovered from the measurements recorded on an aperture outside the support of the source. A major challenge in transcranial PACT brain imaging is to compensate for aberrations in the measured data due to the propagation of the photoacoustic wavefields through the skull. To properly account for these effects, a wave equation-based inversion method should be employed that can model the heterogeneous elastic properties of the medium. In this study, an iterative image reconstruction method for 3D transcranial PACT is developed based on the elastic wave equation. To accomplish this, a forward model based on a finite-difference time-domain discretization of the elastic wave equation is established. Subsequently, gradient-based methods are employed for computing penalized least squares estimates of the initial source distribution that produced the measured photoacoustic data. The developed reconstruction algorithm is validated and investigated through computer-simulation studies.

Bilateral Malar Reconstruction Using Patient-Specific Polyether Ether Ketone Implants in Treacher-Collins Syndrome Patients With Absent Zygomas.

PubMed

Sainsbury, David C G; George, Alan; Forrest, Christopher R; Phillips, John H

2017-03-01

The authors performed bilateral malar reconstruction using polyether ether ketone implants in 3 patients with Treacher-Collins syndrome with absent, as opposed to hypoplastic, zygomata. These patient-specific implants were fabricated using computed-aided design software reformatted from three-dimensional bony preoperative computed tomography images. The first time the authors performed this procedure the implant compressed the globe resulting in temporary anisocoria that was quickly recognized intraoperatively. The implant was immediately removed and the patient made a full-recovery with no ocular disturbance. The computer-aided design and manufacturing process was adjusted to include periorbital soft-tissue boundaries to aid in contouring the new implants. The same patient, and 2 further patients, subsequently underwent malar reconstruction using this soft tissue periorbital boundary fabrication process with an additional 2 mm relief removed from the implant's orbital surface. These subsequent procedures were performed without complication and with pleasing aesthetic results. The authors describe their experience and the salutary lessons learnt.

[Diagnostic possibilities of digital volume tomography].

PubMed

Lemkamp, Michael; Filippi, Andreas; Berndt, Dorothea; Lambrecht, J Thomas

2006-01-01

Cone beam computed tomography allows high quality 3D images of cranio-facial structures. Although detail resolution is increased, x-ray exposition is reduced compared to classic computer tomography. The volume is analysed in three orthogonal plains, which can be rotated independently without quality loss. Cone beam computed tomography seems to be a less expensive and less x-ray exposing alternative to classic computer tomography.

18-Fluorodeoxy-Glucose Positron Emission Tomography- Computed Tomography (18-FDG-PET/CT) for Gross Tumor Volume (GTV) Delineation in Gastric Cancer Radiotherapy

PubMed

Dębiec, Kinga; Wydmański, Jerzy; Gorczewska, Izabela; Leszczyńska, Paulina; Gorczewski, Kamil; Leszczyński, Wojciech; d’Amico, Andrea; Kalemba, Michał

2017-11-26

Purpose: Evaluation of the 18-fluorodeoxy-glucose positron emission tomography-computed tomography (18-FDGPET/ CT) for gross tumor volume (GTV) delineation in gastric cancer patients undergoing radiotherapy. Methods: In this study, 29 gastric cancer patients (17 unresectable and 7 inoperable) were initially enrolled for radical chemoradiotherapy (45Gy/25 fractions + chemotherapy based on 5 fluorouracil) or radiotherapy alone (45Gy/25 fractions) with planning based on the 18-FDG-PET/CT images. Five patients were excluded due to excess blood glucose levels (1), false-negative positron emission tomography (1) and distant metastases revealed by 18-FDG-PET/CT (3). The analysis involved measurement of metabolic tumor volumes (MTVs) performed on PET/CT workstations. Different threshold levels of the standardized uptake value (SUV) and liver uptake were set to obtain MTVs. Secondly, GTVPET values were derived manually using the positron emission tomography (PET) dataset blinded to the computed tomography (CT) data. Subsequently, GTVCT values were delineated using a radiotherapy planning system based on the CT scans blinded to the PET data. The referenced GTVCT values were correlated with the GTVPET and were compared with a conformality index (CI). Results: The mean CI was 0.52 (range, 0.12-0.85). In 13/24 patients (54%), the GTVPET was larger than GTVCT, and in the remainder, GTVPET was smaller. Moreover, the cranio-caudal diameter of GTVPET in 16 cases (64%) was larger than that of GTVCT, smaller in 7 cases (29%), and unchanged in one case. Manual PET delineation (GTVPET) achieved the best correlation with GTVCT (Pearson correlation = 0.76, p <0.0001). Among the analyzed MTVs, a statistically significant correlation with GTVCT was revealed for MTV10%SUVmax (r = 0.63; p = 0.0014), MTVliv (r = 0.60; p = 0.0021), MTVSUV2.5 (r = 0.54; p = 0.0063); MTV20%SUVmax (r = 0.44; p = 0.0344); MTV30%SUVmax (r = 0.44; p = 0.0373). Conclusion: 18-FDG-PET/CT in gastric cancer radiotherapy planning may affect the GTV delineation. https://www.ncbi.nlm.nih.gov/pubmed/management

Acute lower extremity paralysis after lower extremity endovascular intervention.

PubMed

Öztürk, Semi; Kalyoncuoğlu, Muhsin; Durmuş, Gündüz; Topçu, Adem; Can, Mehmet

2017-04-01

A 61-year-old man underwent successful percutaneous revascularization of both lower limbs with multiple stent implantations. Paralysis of right lower limb was noticed after completion of procedure when transferring the patient from angiography table. Since hematoma compressing lumbosacral neural plexus could be a fatal complication, computed tomography (CT) image was taken. CT showed bulge of distended bladder compressing stent struts. Following placement of Foley catheter, condition improved and he was subsequently discharged uneventfully.

Isolated gallbladder injury in a case of blunt abdominal trauma.

PubMed

Birn, Jeffrey; Jung, Melissa; Dearing, Mark

2012-04-01

The diagnosis of blunt injury to the gallbladder may constitute a significant challenge to the diagnostician. There is often a delay in presentation with non-specific clinical symptoms. In the absence of reliable clinical symptoms, diagnostic imaging becomes an invaluable tool in the rapid identification of gallbladder injury. We present a case of isolated gallbladder injury following blunt abdominal trauma which was diagnosed by computed tomography and subsequently confirmed by cholecystectomy.

Asymmetric lumbosacral transitional vertebra and subsequent disc protrusion in a cocker spaniel

PubMed Central

Archer, Rebecca; Sissener, Thomas; Connery, Neil; Spotswood, Tim

2010-01-01

A 10-year-old cocker spaniel bitch presented with severe lumbosacral pain and acute onset left pelvic limb lameness. A diagnosis of asymmetric lumbosacral transitional vertebra with disc protrusion at L6-L7 was made by computed tomography. The cauda equina and left L6 nerve root were surgically decompressed with a dorsal laminectomy and lateral foraminotomy, which led to rapid resolution of the clinical signs. PMID:20514255

Disseminated Multi-system Sarcoidosis Mimicking Metastases on 18F-FDG PET/CT.

PubMed

Makis, William; Palayew, Mark; Rush, Christopher; Probst, Stephan

2018-06-07

A 60-year-old female with no significant medical history presented with hematuria. A computed tomography (CT) scan revealed extensive lymphadenopathy with hypodensities in the liver and spleen, and she was referred for an 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/CT (PET/CT) study to assess for malignancy of unknown primary. PET/CT revealed extensive 18 F-FDG avid lymphadenopathy as well as innumerable intensely 18 F-FDG avid lung, liver and splenic nodules, highly concerning for malignancy. A PET-guided bone marrow biopsy of the posterior superior iliac spine revealed several non-necrotizing, well-formed granulomas, consistent with sarcoidosis. The patient was managed conservatively and remained clinically well over the subsequent 9 years of follow-up.

Computed Tomography

NASA Astrophysics Data System (ADS)

Castellano, Isabel; Geleijns, Jacob

After its clinical introduction in 1973, computed tomography developed from an x-ray modality for axial imaging in neuroradiology into a versatile three dimensional imaging modality for a wide range of applications in for example oncology, vascular radiology, cardiology, traumatology and even in interventional radiology. Computed tomography is applied for diagnosis, follow-up studies and screening of healthy subpopulations with specific risk factors. This chapter provides a general introduction in computed tomography, covering a short history of computed tomography, technology, image quality, dosimetry, room shielding, quality control and quality criteria.

Acute Subdural Hematoma in a Judo Player with Repeated Head Injuries.

PubMed

Yokota, Hiroshi; Ida, Yuki

2016-07-01

Acute subdural hematoma (ASDH) is the most important cause of severe head injuries occurring during judo practice in Japan. Repeated head injuries have been reported as a cause of fatal ASDH, although the mechanism remains unknown. A 16-year-old boy visited an emergency department with vomiting 3 days after a strong blow to the occipital region during judo practice. Although computed tomography was performed at that time, a small interhemispheric ASDH was overlooked. The patient sustained another head injury 19 days after the first, which led to convulsions and disturbance of consciousness. The ASDH was increased in size on computed tomography. We performed a surgical evacuation, which revealed tearing of a bridging vein, after which the patient showed a good recovery. It is important to be aware of the possibility of a small ASDH in concussed judo players after an initial impact, which may lead to subsequent fatal ASDH after another impact incident. Copyright © 2016 Elsevier Inc. All rights reserved.

Management of a maxillary first molar having atypical anatomy of two roots diagnosed using cone beam computed tomography.

PubMed

Sharma, Sarang; Mittal, Meenu; Passi, Deepak; Grover, Shibani

2015-01-01

Most often, a clinician working on maxillary first molar when anticipates an aberration thinks of an extra canal but rarely does he preempt fewer canals. Maxillary first molar is a tooth, which has been extensively reviewed with respect to its external and internal morphology. Abundant literature related to its anatomy is available, but reports on incidence of two roots and two root canals in maxillary first molar are very limited. Here, a case of maxillary first molar is presented that had two roots: one palatal root with Type I canal configuration and one bulbous fused buccal root with Type V canal configuration; a unique root and canal configuration not seen in any of the earlier reported cases. Diagnosis of root canal aberrancy and subsequently, accurate management of the tooth was greatly facilitated by cone beam computed tomography (CBCT) scan. The relevance of CBCT in improving treatment prognosis is greatly emphasized in this report.

Imaging and Analysis of Void-defects in Solder Joints Formed in Reduced Gravity using High-Resolution Computed Tomography

NASA Technical Reports Server (NTRS)

Easton, John W.; Struk, Peter M.; Rotella, Anthony

2008-01-01

As a part of efforts to develop an electronics repair capability for long duration space missions, techniques and materials for soldering components on a circuit board in reduced gravity must be developed. This paper presents results from testing solder joint formation in low gravity on a NASA Reduced Gravity Research Aircraft. The results presented include joints formed using eutectic tin-lead solder and one of the following fluxes: (1) a no-clean flux core, (2) a rosin flux core, and (3) a solid solder wire with external liquid no-clean flux. The solder joints are analyzed with a computed tomography (CT) technique which imaged the interior of the entire solder joint. This replaced an earlier technique that required the solder joint to be destructively ground down revealing a single plane which was subsequently analyzed. The CT analysis technique is described and results presented with implications for future testing as well as implications for the overall electronics repair effort discussed.

A new Mumford-Shah total variation minimization based model for sparse-view x-ray computed tomography image reconstruction.

PubMed

Chen, Bo; Bian, Zhaoying; Zhou, Xiaohui; Chen, Wensheng; Ma, Jianhua; Liang, Zhengrong

2018-04-12

Total variation (TV) minimization for the sparse-view x-ray computer tomography (CT) reconstruction has been widely explored to reduce radiation dose. However, due to the piecewise constant assumption for the TV model, the reconstructed images often suffer from over-smoothness on the image edges. To mitigate this drawback of TV minimization, we present a Mumford-Shah total variation (MSTV) minimization algorithm in this paper. The presented MSTV model is derived by integrating TV minimization and Mumford-Shah segmentation. Subsequently, a penalized weighted least-squares (PWLS) scheme with MSTV is developed for the sparse-view CT reconstruction. For simplicity, the proposed algorithm is named as 'PWLS-MSTV.' To evaluate the performance of the present PWLS-MSTV algorithm, both qualitative and quantitative studies were conducted by using a digital XCAT phantom and a physical phantom. Experimental results show that the present PWLS-MSTV algorithm has noticeable gains over the existing algorithms in terms of noise reduction, contrast-to-ratio measure and edge-preservation.

Image-guided transnasal cryoablation of a recurrent nasal adenocarcinoma in a dog.

PubMed

Murphy, S M; Lawrence, J A; Schmiedt, C W; Davis, K W; Lee, F T; Forrest, L J; Bjorling, D E

2011-06-01

An eight-year-old female spayed Airedale terrier with rapid recurrence of a nasal adenocarcinoma following image-guided intensity-modulated radiation therapy was treated with transnasal, image-guided cryotherapy. Ice ball size and location were monitored real-time with computed tomography-fluoroscopy to verify that the entire tumour was enveloped in ice. Serial computed tomography scans demonstrated reduction in and subsequent resolution of the primary tumour volume corresponding visually with the ice ball imaged during the ablation procedure. Re-imaging demonstrated focallysis of the cribriform plate following ablation that spontaneously resolved by 13 months. While mild chronic nasal discharge developed following cryoablation, no other clinical signs of local nasal neoplasia were present. Twenty-one months after nasal tumour cryoablation the dog was euthanased as a result of acute haemoabdomen. Image-guided cryotherapy may warrant further investigation for the management of focal residual or recurrent tumours in dogs, especially in regions where critical structures preclude surgical intervention. © 2011 British Small Animal Veterinary Association.

Preoperative N Staging of Gastric Cancer by Stomach Protocol Computed Tomography

PubMed Central

Kim, Se Hoon; Kim, Jeong Jae; Lee, Jeong Sub; Kim, Seung Hyoung; Kim, Bong Soo; Maeng, Young Hee; Hyun, Chang Lim; Kim, Min Jeong

2013-01-01

Purpose Clinical stage of gastric cancer is currently assessed by computed tomography. Accurate clinical staging is important for the tailoring of therapy. This study evaluated the accuracy of clinical N staging using stomach protocol computed tomography. Materials and Methods Between March 2004 and November 2012, 171 patients with gastric cancer underwent preoperative stomach protocol computed tomography (Jeju National University Hospital; Jeju, Korea). Their demographic and clinical characteristics were reviewed retrospectively. Two radiologists evaluated cN staging using axial and coronal computed tomography images, and cN stage was matched with pathologic results. The diagnostic accuracy of stomach protocol computed tomography for clinical N staging and clinical characteristics associated with diagnostic accuracy were evaluated. Results The overall accuracy of stomach protocol computed tomography for cN staging was 63.2%. Computed tomography images of slice thickness 3.0 mm had a sensitivity of 60.0%; a specificity of 89.6%; an accuracy of 78.4%; and a positive predictive value of 78.0% in detecting lymph node metastases. Underestimation of cN stage was associated with larger tumor size (P<0.001), undifferentiated type (P=0.003), diffuse type (P=0.020), more advanced pathologic stage (P<0.001), and larger numbers of harvested and metastatic lymph nodes (P<0.001 each). Tumor differentiation was an independent factor affecting underestimation by computed tomography (P=0.045). Conclusions Computed tomography with a size criterion of 8 mm is highly specific but relatively insensitive in detecting nodal metastases. Physicians should keep in mind that computed tomography may not be an appropriate tool to detect nodal metastases for choosing appropriate treatment. PMID:24156034

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

Deshmukh, Hemant; Rathod, Krantikumar; Garg, Ashwin, E-mail: ashwingarg@indiatimes.com

Mycotic pseudoaneurysm of the pulmonary artery that ruptures during necrotizing pneumonia is a rare entity that is often fatal. Traditionally it has been treated with open thoracotomy and resection of both the aneurysm and the lobe in which the aneurysm is located. In this report, we describe the radiological findings and transcatheter coil embolization of a mycotic pulmonary pseudoaneurysm in a 6-month-old female infant. We also describe the subsequent morphologic changes observed on follow-up computed tomography after 9 months of embolization.

Initial screening test for blunt cerebrovascular injury: Validity assessment of whole-body computed tomography.

PubMed

Laser, Adriana; Kufera, Joseph A; Bruns, Brandon R; Sliker, Clint W; Tesoriero, Ronald B; Scalea, Thomas M; Stein, Deborah M

2015-09-01

Our whole-body computed tomography protocol (WBCT), used to image patients with polytrauma, consists of a noncontrast head computed tomography (CT) followed by a multidetector computed tomography (40- or 64- slice) that includes an intravenous, contrast-enhanced scan from the face through the pelvis. WBCT is used to screen for blunt cerebrovascular injury (BCVI) during initial CT imaging of the patient with polytrauma and allows for early initiation of therapy with the goal of avoiding stroke. WBCT has not been directly compared with CT angiography (CTA) of the neck as a screening tool for BCVI. We hypothesize that WBCT is a valid modality to diagnose BCVI compared with neck CTA, thus screening patients with polytrauma for BCVI and limiting the need for subsequent CTA. A retrospective review of the trauma registry was conducted for all patients diagnosed with BCVI from June 2009 to June 2013 at our institution. All injuries, identified and graded on initial WBCT, were compared with neck CTA imaging performed within the first 72 hours. Sensitivity was calculated for WBCT by the use of CTA as the reference standard. Proportions of agreement also were calculated between the grades of injury for both imaging modalities. A total of 319 injured vessels were identified in 227 patients. On initial WBCT 80 (25%) of the injuries were grade I, 75 (24%) grade II, 45 (14%) grade III, 41 (13%) grade IV, and 58 (18%) were classified as indeterminate: 27 vertebral and 31 carotid lesions. Twenty (6%) of the 319 injuries were not detected on WBCT but identified on subsequent CTA (9 grade I, 7 grade II, 4 grade III); 6 vertebral and 14 carotid. For each vessel type and for all vessels combined, WBCT demonstrated sensitivity rates of over 90% to detect BCVI among the population of patients with at least one vessel injured. There was concordant grading of injuries between WBCT and initial diagnostic CTA in 154 (48% of all injuries). Lower grade injures were more discordant than higher grades (55% vs 13%, respectively; P < .001). Grading was upgraded 8% of the time and downgraded 25%. WBCT holds promise as a rapid screening test for BCVI in the patient with polytrauma to identify injuries in the early stage of the trauma evaluation, thus allowing more rapid initiation of treatment. In addition, in those patients with high risk for BCVI but whose WBCT results are negative for BCVI, neck CTA should be considered to more confidently exclude low-grade injuries. Copyright © 2015 Elsevier Inc. All rights reserved.

[Computed tomography with computer-assisted detection of pulmonary nodules in dogs and cats].

PubMed

Niesterok, C; Piesnack, S; Köhler, C; Ludewig, E; Alef, M; Kiefer, I

2015-01-01

The aim of this study was to assess the potential benefit of computer-assisted detection (CAD) of pulmonary nodules in veterinary medicine. Therefore, the CAD rate was compared to the detection rates of two individual examiners in terms of its sensitivity and false-positive findings. We included 51 dogs and 16 cats with pulmonary nodules previously diagnosed by computed tomography. First, the number of nodules ≥ 3 mm was recorded for each patient by two independent examiners. Subsequently, each examiner used the CAD software for automated nodule detection. With the knowledge of the CAD results, a final consensus decision on the number of nodules was achieved. The software used was a commercially available CAD program. The sensitivity of examiner 1 was 89.2%, while that of examiner 2 reached 87.4%. CAD had a sensitivity of 69.4%. With CAD, the sensitivity of examiner 1 increased to 94.7% and that of examiner 2 to 90.8%. The CAD-system, which we used in our study, had a moderate sensitivity of 69.4%. Despite its severe limitations, with a high level of false-positive and false-negative results, CAD increased the examiners' sensitivity. Therefore, its supportive role in diagnostics appears to be evident.

Computed tomography vs. digital radiography assessment for detection of osteolysis in asymptomatic patients with uncemented cups: a proposal for a new classification system based on computer tomography.

PubMed

Sandgren, Buster; Crafoord, Joakim; Garellick, Göran; Carlsson, Lars; Weidenhielm, Lars; Olivecrona, Henrik

2013-10-01

Digital radiographic images in the anterior-posterior and lateral view have been gold standard for evaluation of peri-acetabular osteolysis for patients with an uncemented hip replacement. We compared digital radiographic images and computer tomography in detection of peri-acetabular osteolysis and devised a classification system based on computer tomography. Digital radiographs were compared with computer tomography on 206 hips, with a mean follow up 10 years after surgery. The patients had no clinical signs of osteolysis and none were planned for revision surgery. On digital radiographs, 192 cases had no osteolysis and only 14 cases had osteolysis. When using computer tomography there were 184 cases showing small or large osteolysis and only 22 patients had no osteolysis. A classification system for peri-acetabular osteolysis is proposed based on computer tomography that is easy to use on standard follow up evaluation. Copyright © 2013 Elsevier Inc. All rights reserved.

Computer-aided diagnosis in phase contrast imaging X-ray computed tomography for quantitative characterization of ex vivo human patellar cartilage.

PubMed

Nagarajan, Mahesh B; Coan, Paola; Huber, Markus B; Diemoz, Paul C; Glaser, Christian; Wismuller, Axel

2013-10-01

Visualization of ex vivo human patellar cartilage matrix through the phase contrast imaging X-ray computed tomography (PCI-CT) has been previously demonstrated. Such studies revealed osteoarthritis-induced changes to chondrocyte organization in the radial zone. This study investigates the application of texture analysis to characterizing such chondrocyte patterns in the presence and absence of osteoarthritic damage. Texture features derived from Minkowski functionals (MF) and gray-level co-occurrence matrices (GLCM) were extracted from 842 regions of interest (ROI) annotated on PCI-CT images of ex vivo human patellar cartilage specimens. These texture features were subsequently used in a machine learning task with support vector regression to classify ROIs as healthy or osteoarthritic; classification performance was evaluated using the area under the receiver operating characteristic curve (AUC). The best classification performance was observed with the MF features perimeter (AUC: 0.94 ±0.08 ) and "Euler characteristic" (AUC: 0.94 ±0.07 ), and GLCM-derived feature "Correlation" (AUC: 0.93 ±0.07). These results suggest that such texture features can provide a detailed characterization of the chondrocyte organization in the cartilage matrix, enabling classification of cartilage as healthy or osteoarthritic with high accuracy.

Assessment of the Role of Different Imaging Modalities with Emphasis on Fdg Pet/Ct in the Management of Well Differentiated Thyroid Cancer (WDTC).

PubMed

Kendi A, Tuba Karagulle; Mudalegundi, Shwetha; Switchenko, Jeffrey; Lee, Daniel; Halkar, Raghuveer; Chen, Amy Y

2016-01-01

Positron emission tomography/computed tomography is suggested to have a role in detection of iodine negative recurrence in well differentiated thyroid cancer. The aim of this study is to identify role of different imaging modalities in the management of well differentiated thyroid cancer. We reviewed 900 well differentiated thyroid cancer patients after post-thyroidectomy who underwent recombinant human thyroid stimulating hormone stimulated Sodium Iodide I 131 imaging. Out of 900 patients, 74 had positron emission tomography/computed tomography. Multivariate analysis was performed by controlling positron emission tomography/computed tomography, Sodium Iodide I 131 scan, neck ultrasonography, age, sex, primary tumor size, stage, histology, thyroglobulin. Patients were grouped according to results of Sodium Iodide I 131 scan and positron emission tomography/computed tomography. Positron emission tomography/computed tomography was positive in 23 of 74 patients. The sensitivity for positron emission tomography was 11/11(100%), the specificity was 51/63 (81.0%), the positive predictive value was 11/23 (47.8%), and the negative predictive value was 51/51 (100%). The sensitivity for the neck ultrasonography was 4/8 (50%), the specificity was 53/60 (88.3%), positive predictive value was 4/11 (36.4%), and negative predictive value was 53/57 (93.0%). 50% of patients who had Sodium Iodide I 131 negative scan and positive positron emission tomography/computed tomography had a change in management. Thirty-six percent with positive neck ultrasonography had a change in management. Out of 11 recurrences, 6 had distant metastatic disease, and 5/11 had regional nodal disease. Neck ultrasonography showed nodal metastasis in 4/5 (80%). Positron emission tomography/computed tomography altered management in the presence of a high thyroglobulin level and a negative Sodium Iodide I 131 scan. Neck ultrasonography should be the first line of imaging with rising thyroglobulin levels. Positron emission tomography/computed tomography should be considered for cases with high thyroglobulin levels and normal neck ultrasonography to look for distant metastatic disease.

Body CT (CAT Scan)

MedlinePlus

... Resources Professions Site Index A-Z Computed Tomography (CT) - Body Computed tomography (CT) of the body uses ... of CT Scanning of the Body? What is CT Scanning of the Body? Computed tomography, more commonly ...

Role of multidetector computed tomography in the diagnosis and management of patients attending the rapid access chest pain clinic, The Scottish computed tomography of the heart (SCOT-HEART) trial: study protocol for randomized controlled trial

PubMed Central

2012-01-01

Background Rapid access chest pain clinics have facilitated the early diagnosis and treatment of patients with coronary heart disease and angina. Despite this important service provision, coronary heart disease continues to be under-diagnosed and many patients are left untreated and at risk. Recent advances in imaging technology have now led to the widespread use of noninvasive computed tomography, which can be used to measure coronary artery calcium scores and perform coronary angiography in one examination. However, this technology has not been robustly evaluated in its application to the clinic. Methods/design The SCOT-HEART study is an open parallel group prospective multicentre randomized controlled trial of 4,138 patients attending the rapid access chest pain clinic for evaluation of suspected cardiac chest pain. Following clinical consultation, participants will be approached and randomized 1:1 to receive standard care or standard care plus ≥64-multidetector computed tomography coronary angiography and coronary calcium score. Randomization will be conducted using a web-based system to ensure allocation concealment and will incorporate minimization. The primary endpoint of the study will be the proportion of patients diagnosed with angina pectoris secondary to coronary heart disease at 6 weeks. Secondary endpoints will include the assessment of subsequent symptoms, diagnosis, investigation and treatment. In addition, long-term health outcomes, safety endpoints, such as radiation dose, and health economic endpoints will be assessed. Assuming a clinic rate of 27.0% for the diagnosis of angina pectoris due to coronary heart disease, we will need to recruit 2,069 patients per group to detect an absolute increase of 4.0% in the rate of diagnosis at 80% power and a two-sided P value of 0.05. The SCOT-HEART study is currently recruiting participants and expects to report in 2014. Discussion This is the first study to look at the implementation of computed tomography in the patient care pathway that is outcome focused. This study will have major implications for the management of patients with cardiovascular disease. Trial registration ClinicalTrials.gov Identifier: NCT01149590 PMID:23036114

Neuroimaging Techniques: a Conceptual Overview of Physical Principles, Contribution and History

NASA Astrophysics Data System (ADS)

Minati, Ludovico

2006-06-01

This paper is meant to provide a brief overview of the techniques currently used to image the brain and to study non-invasively its anatomy and function. After a historical summary in the first section, general aspects are outlined in the second section. The subsequent six sections survey, in order, computed tomography (CT), morphological magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), diffusion-tensor magnetic resonance imaging (DWI/DTI), positron emission tomography (PET), and electro- and magneto-encephalography (EEG/MEG) based imaging. Underlying physical principles, modelling and data processing approaches, as well as clinical and research relevance are briefly outlined for each technique. Given the breadth of the scope, there has been no attempt to be comprehensive. The ninth and final section outlines some aspects of active research in neuroimaging.

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

Minati, Ludovico

This paper is meant to provide a brief overview of the techniques currently used to image the brain and to study non-invasively its anatomy and function. After a historical summary in the first section, general aspects are outlined in the second section. The subsequent six sections survey, in order, computed tomography (CT), morphological magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), diffusion-tensor magnetic resonance imaging (DWI/DTI), positron emission tomography (PET), and electro- and magneto-encephalography (EEG/MEG) based imaging. Underlying physical principles, modelling and data processing approaches, as well as clinical and research relevance are briefly outlined for each technique. Givenmore » the breadth of the scope, there has been no attempt to be comprehensive. The ninth and final section outlines some aspects of active research in neuroimaging.« less

Evaluation of a deformable registration algorithm for subsequent lung computed tomography imaging during radiochemotherapy

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

Stützer, Kristin; Haase, Robert; Exner, Florian

2016-09-15

Purpose: Rating both a lung segmentation algorithm and a deformable image registration (DIR) algorithm for subsequent lung computed tomography (CT) images by different evaluation techniques. Furthermore, investigating the relative performance and the correlation of the different evaluation techniques to address their potential value in a clinical setting. Methods: Two to seven subsequent CT images (69 in total) of 15 lung cancer patients were acquired prior, during, and after radiochemotherapy. Automated lung segmentations were compared to manually adapted contours. DIR between the first and all following CT images was performed with a fast algorithm specialized for lung tissue registration, requiring themore » lung segmentation as input. DIR results were evaluated based on landmark distances, lung contour metrics, and vector field inconsistencies in different subvolumes defined by eroding the lung contour. Correlations between the results from the three methods were evaluated. Results: Automated lung contour segmentation was satisfactory in 18 cases (26%), failed in 6 cases (9%), and required manual correction in 45 cases (66%). Initial and corrected contours had large overlap but showed strong local deviations. Landmark-based DIR evaluation revealed high accuracy compared to CT resolution with an average error of 2.9 mm. Contour metrics of deformed contours were largely satisfactory. The median vector length of inconsistency vector fields was 0.9 mm in the lung volume and slightly smaller for the eroded volumes. There was no clear correlation between the three evaluation approaches. Conclusions: Automatic lung segmentation remains challenging but can assist the manual delineation process. Proven by three techniques, the inspected DIR algorithm delivers reliable results for the lung CT data sets acquired at different time points. Clinical application of DIR demands a fast DIR evaluation to identify unacceptable results, for instance, by combining different automated DIR evaluation methods.« less

[Lupus enteritis as initial manifestation of systemic lupus erythematosus. Report of one case].

PubMed

Barrera O, Manuel; Barrera M, Rodrigo; de la Rivera V, Matías; Vela U, Javier; Mönckeberg F, Gustavo

2017-10-01

Although gastrointestinal symptoms are not rare in Systemic lupus erythematosus, enteritis is an atypical manifestation of the disease. We report a 54 year-old woman who presented acute symptoms of diarrhea, fever and abdominal pain, receiving empiric antibiotic therapy for bacterial enteritis with no response. Computed tomography showed diffuse small intestine inflammation and serositis. Antinuclear antibodies, anti-Ro and anti-La were positive on blood tests. A lupic enteropathy was diagnosed and steroid treatment was initiated, with subsequent clinical improvement.

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

Matsui, O.; Takashima, T.; Kadoya, M.

Peripheral obstruction of intrahepatic portal vein branches was detected by dynamic sequential computed tomography during arterial portography and subsequently confirmed surgically in 9 patients with hepatic neoplasm (7 hepatocellular carcinomas, 1 cholangiocarcinoma, and 1 metastatic lymphadenopathy from gastric carcinoma). Eight of these 10 segments showed more dense staining than other regions of the liver during infusion hepatic angiography. This pattern was attributed to trans-sinusoidal or peripheral arterioportal shunting. In 5 cases, the segmental staining obscured the tumor stain, making the tumor appear larger than it actually was or causing it to be missed altogether.

Odontoid fracture following a fall in an elderly man.

PubMed

Pagnez, Maria Alice Mainenti; Elliott, James M

2011-12-01

The patient was a 79-year-old man with a chief complaint of neck pain after a fall. Three days following the fall, the patient was seen in the emergency department, where computed tomography imaging of the head and radiographs of the cervical spine were completed. The patient was subsequently referred to a physical therapist. Due to concern for a possible undetected cervical spine fracture, the patient was immediately referred to his physician. Magnetic resonance imaging demonstrated a type II fracture of the odontoid.

Indium-111 leukocyte scintigraphy in Wegener's granulomatosis involving the spleen

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

Morayati, S.J.; Fink-Bennett, D.

1986-12-01

Indium-111-labeled leukocyte scintigraphy was performed on a 44-yr-old man to exclude an occult abscess. Four- and twenty-four-hour images of the abdomen revealed splenic photopenia except for a rim of activity medially. A subsequent computed tomography (CT) study demonstrated necrosis or hemorrhage of the spleen except for a medial rim. Exploratory laparotomy demonstrated necrotizing vasculitis with granuloma formation consistent with Wegener's granulomatosis and a rim of viable splenic tissue corresponding to the radionuclide and CT studies.

[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.

Interstitial Lung Disease due to Siderosis in a Lathe Machine Worker.

PubMed

Gothi, D; Satija, B; Kumar, S; Kaur, Omkar

2015-01-01

Since its first description in 1936, siderosis of lung has been considered a benign pneumoconiosis due to absence of significant clinical symptoms or respiratory impairment. Subsequently, authors have questioned the non-fibrogenic property of iron. However, siderosis causing interstitial lung disease with usual interstitial pneumonia (UIP) pattern has not been described in the past. We report a case of UIP on high resolution computed tomography, proven to be siderosis on transbronchial lung biopsy in a lathe machine worker.

68Ga/177Lu-labeled DOTA-TATE shows similar imaging and biodistribution in neuroendocrine tumor model.

PubMed

Liu, Fei; Zhu, Hua; Yu, Jiangyuan; Han, Xuedi; Xie, Qinghua; Liu, Teli; Xia, Chuanqin; Li, Nan; Yang, Zhi

2017-06-01

Somatostatin receptors are overexpressed in neuroendocrine tumors, whose endogenous ligands are somatostatin. DOTA-TATE is an analogue of somatostatin, which shows high binding affinity to somatostatin receptors. We aim to evaluate the 68 Ga/ 177 Lu-labeling DOTA-TATE kit in neuroendocrine tumor model for molecular imaging and to try human-positron emission tomography/computed tomography imaging of 68 Ga-DOTA-TATE in neuroendocrine tumor patients. DOTA-TATE kits were formulated and radiolabeled with 68 Ga/ 177 Lu for 68 Ga/ 177 Lu-DOTA-TATE (M-DOTA-TATE). In vitro and in vivo stability of 177 Lu-DOTA-TATE were performed. Nude mice bearing human tumors were injected with 68 Ga-DOTA-TATE or 177 Lu-DOTA-TATE for micro-positron emission tomography and micro-single-photon emission computed tomography/computed tomography imaging separately, and clinical positron emission tomography/computed tomography images of 68 Ga-DOTA-TATE were obtained at 1 h post-intravenous injection from patients with neuroendocrine tumors. Micro-positron emission tomography and micro-single-photon emission computed tomography/computed tomography imaging of 68 Ga-DOTA-TATE and 177 Lu-DOTA-TATE both showed clear tumor uptake which could be blocked by excess DOTA-TATE. In addition, 68 Ga-DOTA-TATE-positron emission tomography/computed tomography imaging in neuroendocrine tumor patients could show primary and metastatic lesions. 68 Ga-DOTA-TATE and 177 Lu-DOTA-TATE could accumulate in tumors in animal models, paving the way for better clinical peptide receptor radionuclide therapy for neuroendocrine tumor patients in Asian population.

Dual-Energy Computed Tomography in Cardiothoracic Vascular Imaging.

PubMed

De Santis, Domenico; Eid, Marwen; De Cecco, Carlo N; Jacobs, Brian E; Albrecht, Moritz H; Varga-Szemes, Akos; Tesche, Christian; Caruso, Damiano; Laghi, Andrea; Schoepf, Uwe Joseph

2018-07-01

Dual energy computed tomography is becoming increasingly widespread in clinical practice. It can expand on the traditional density-based data achievable with single energy computed tomography by adding novel applications to help reach a more accurate diagnosis. The implementation of this technology in cardiothoracic vascular imaging allows for improved image contrast, metal artifact reduction, generation of virtual unenhanced images, virtual calcium subtraction techniques, cardiac and pulmonary perfusion evaluation, and plaque characterization. The improved diagnostic performance afforded by dual energy computed tomography is not associated with an increased radiation dose. This review provides an overview of dual energy computed tomography cardiothoracic vascular applications. Copyright © 2018 Elsevier Inc. All rights reserved.

A Freeware Path to Neutron Computed Tomography

NASA Astrophysics Data System (ADS)

Schillinger, Burkhard; Craft, Aaron E.

Neutron computed tomography has become a routine method at many neutron sources due to the availability of digital detection systems, powerful computers and advanced software. The commercial packages Octopus by Inside Matters and VGStudio by Volume Graphics have been established as a quasi-standard for high-end computed tomography. However, these packages require a stiff investment and are available to the users only on-site at the imaging facility to do their data processing. There is a demand from users to have image processing software at home to do further data processing; in addition, neutron computed tomography is now being introduced even at smaller and older reactors. Operators need to show a first working tomography setup before they can obtain a budget to build an advanced tomography system. Several packages are available on the web for free; however, these have been developed for X-rays or synchrotron radiation and are not immediately useable for neutron computed tomography. Three reconstruction packages and three 3D-viewers have been identified and used even for Gigabyte datasets. This paper is not a scientific publication in the classic sense, but is intended as a review to provide searchable help to make the described packages usable for the tomography community. It presents the necessary additional preprocessing in ImageJ, some workarounds for bugs in the software, and undocumented or badly documented parameters that need to be adapted for neutron computed tomography. The result is a slightly complicated, but surprisingly high-quality path to neutron computed tomography images in 3D, but not a replacement for the even more powerful commercial software mentioned above.

Terahertz Computed Tomography of NASA Thermal Protection System Materials

NASA Technical Reports Server (NTRS)

Roth, D. J.; Reyes-Rodriguez, S.; Zimdars, D. A.; Rauser, R. W.; Ussery, W. W.

2011-01-01

A terahertz axial computed tomography system has been developed that uses time domain measurements in order to form cross-sectional image slices and three-dimensional volume renderings of terahertz-transparent materials. The system can inspect samples as large as 0.0283 cubic meters (1 cubic foot) with no safety concerns as for x-ray computed tomography. In this study, the system is evaluated for its ability to detect and characterize flat bottom holes, drilled holes, and embedded voids in foam materials utilized as thermal protection on the external fuel tanks for the Space Shuttle. X-ray micro-computed tomography was also performed on the samples to compare against the terahertz computed tomography results and better define embedded voids. Limits of detectability based on depth and size for the samples used in this study are loosely defined. Image sharpness and morphology characterization ability for terahertz computed tomography are qualitatively described.

Congruence Between Pulmonary Function and Computed Tomography Imaging Assessment of Cystic Fibrosis Severity.

PubMed

Rybacka, Anna; Goździk-Spychalska, Joanna; Rybacki, Adam; Piorunek, Tomasz; Batura-Gabryel, Halina; Karmelita-Katulska, Katarzyna

2018-05-04

In cystic fibrosis, pulmonary function tests (PFTs) and computed tomography are used to assess lung function and structure, respectively. Although both techniques of assessment are congruent there are lingering doubts about which PFTs variables show the best congruence with computed tomography scoring. In this study we addressed the issue by reinvestigating the association between PFTs variables and the score of changes seen in computed tomography scans in patients with cystic fibrosis with and without pulmonary exacerbation. This retrospective study comprised 40 patients in whom PFTs and computed tomography were performed no longer than 3 weeks apart. Images (inspiratory: 0.625 mm slice thickness, 0.625 mm interval; expiratory: 1.250 mm slice thickness, 10 mm interval) were evaluated with the Bhalla scoring system. The most frequent structural abnormality found in scans were bronchiectases and peribronchial thickening. The strongest relationship was found between the Bhalla sore and forced expiratory volume in 1 s (FEV1). The Bhalla sore also was related to forced vital capacity (FVC), FEV1/FVC ratio, residual volume (RV), and RV/total lung capacity (TLC) ratio. We conclude that lung structural data obtained from the computed tomography examination are highly congruent to lung function data. Thus, computed tomography imaging may supersede functional assessment in cases of poor compliance with spirometry procedures in the lederly or children. Computed tomography also seems more sensitive than PFTs in the assessment of cystic fibrosis progression. Moreover, in early phases of cystic fibrosis, computed tomography, due to its excellent resolution, may be irreplaceable in monitoring pulmonary damage.

Computed tomography identifies patients at high risk for stroke after transient ischemic attack/nondisabling stroke: prospective, multicenter cohort study.

PubMed

Wasserman, Jason K; Perry, Jeffrey J; Sivilotti, Marco L A; Sutherland, Jane; Worster, Andrew; Émond, Marcel; Jin, Albert Y; Oczkowski, Wieslaw J; Sahlas, Demetrios J; Murray, Heather; MacKey, Ariane; Verreault, Steve; Wells, George A; Dowlatshahi, Dar; Stotts, Grant; Stiell, Ian G; Sharma, Mukul

2015-01-01

Ischemia on computed tomography (CT) is associated with subsequent stroke after transient ischemic attack. This study assessed CT findings of acute ischemia, chronic ischemia, or microangiopathy for predicting subsequent stroke after transient ischemic attack. This prospective cohort study enrolled patients with transient ischemic attack or nondisabling stroke that had CT scanning within 24 hours. Primary outcome was subsequent stroke within 90 days. Secondary outcomes were stroke at ≤2 or >2 days. CT findings were classified as ischemia present or absent and acute or chronic or microangiopathy. Analysis used Fisher exact test and multivariate logistic regression. A total of 2028 patients were included; 814 had ischemic changes on CT. Subsequent stroke rate was 3.4% at 90 days and 1.5% at ≤2 days. Stroke risk was greater if baseline CT showed acute ischemia alone (10.6%; P=0.002), acute+chronic ischemia (17.4%; P=0.007), acute ischemia+microangiopathy (17.6%; P=0.019), or acute+chronic ischemia+microangiopathy (25.0%; P=0.029). Logistic regression found acute ischemia alone (odds ratio [OR], 2.61; 95% confidence interval [CI[, 1.22-5.57), acute+chronic ischemia (OR, 5.35; 95% CI, 1.71-16.70), acute ischemia+microangiopathy (OR, 4.90; 95% CI, 1.33-18.07), or acute+chronic ischemia+microangiopathy (OR, 8.04; 95% CI, 1.52-42.63) was associated with a greater risk at 90 days, whereas acute+chronic ischemia (OR, 10.78; 95% CI, 2.93-36.68), acute ischemia+microangiopathy (OR, 8.90; 95% CI, 1.90-41.60), and acute+chronic ischemia+microangiopathy (OR, 23.66; 95% CI, 4.34-129.03) had greater risk at ≤2 days. Only acute ischemia (OR, 2.70; 95% CI, 1.01-7.18; P=0.047) was associated with a greater risk at >2 days. In patients with transient ischemic attack/nondisabling stroke, CT evidence of acute ischemia alone or acute ischemia with chronic ischemia or microangiopathy was associated with increased subsequent stroke risk within 90 days. © 2014 American Heart Association, Inc.

SCCT guidelines for the performance and acquisition of coronary computed tomographic angiography: A report of the society of Cardiovascular Computed Tomography Guidelines Committee: Endorsed by the North American Society for Cardiovascular Imaging (NASCI).

PubMed

Abbara, Suhny; Blanke, Philipp; Maroules, Christopher D; Cheezum, Michael; Choi, Andrew D; Han, B Kelly; Marwan, Mohamed; Naoum, Chris; Norgaard, Bjarne L; Rubinshtein, Ronen; Schoenhagen, Paul; Villines, Todd; Leipsic, Jonathon

In response to recent technological advancements in acquisition techniques as well as a growing body of evidence regarding the optimal performance of coronary computed tomography angiography (coronary CTA), the Society of Cardiovascular Computed Tomography Guidelines Committee has produced this update to its previously established 2009 "Guidelines for the Performance of Coronary CTA" (1). The purpose of this document is to provide standards meant to ensure reliable practice methods and quality outcomes based on the best available data in order to improve the diagnostic care of patients. Society of Cardiovascular Computed Tomography Guidelines for the Interpretation is published separately (2). The Society of Cardiovascular Computed Tomography Guidelines Committee ensures compliance with all existing standards for the declaration of conflict of interest by all authors and reviewers for the purpose ofclarity and transparency. Copyright © 2016 Society of Cardiovascular Computed Tomography. All rights reserved.

A Combination of Two Rare Coronary Anomalies Makes It Even Rarer: Right Sided Single Coronary Artery with Dual Left Anterior Descending Artery

PubMed Central

Addai, Theodore; Kola, Monahar; Raqeem, Muhammad Wajih; Barsamyan, Sergey; Mirrakhimov, Aibek E.

2016-01-01

An 82-year-old female with history of hyperlipidemia and hypertension presented to the clinic with chief complaint of nonradiating chest tightness accompanied by exertional dyspnea. Cardiac catheterization showed the absence of left coronary system; the entire coronary system originated from the right aortic sinus as a common trunk which then gave off the right coronary artery and the left main coronary artery. Cardiac catheterization demonstrated also another rare coronary anomaly: dual left anterior descending artery. Patient underwent percutaneous coronary intervention and subsequent multidetector computed tomography angiography confirmed the above angiography findings. Patient was subsequently discharged home on double antiplatelet therapy with aspirin and clopidogrel and has been asymptomatic since then. PMID:27293909

Application of multidetector-row computed tomography in propeller flap planning.

PubMed

Ono, Shimpei; Chung, Kevin C; Hayashi, Hiromitsu; Ogawa, Rei; Takami, Yoshihiro; Hyakusoku, Hiko

2011-02-01

The propeller flap is defined as (1) being island-shaped, (2) having an axis that includes the perforators, and (3) having the ability to be rotated around an axis. The advantage of the propeller flap is that it is a pedicle flap that can be applied to cover defects located at the distal ends of the extremities. The specific aims of the authors' study were (1) to evaluate the usefulness of multidetector-row computed tomography in the planning of propeller flaps and (2) to present a clinical case series of propeller flap reconstructions that were planned preoperatively using multidetector-row computed tomography. The authors retrospectively analyzed all cases between April of 2007 and April of 2010 at Nippon Medical School Hospital in Tokyo, where multidetector-row computed tomography was used preoperatively to plan surgical reconstructions using propeller flaps. Thirteen patients underwent 16 flaps using the propeller flap technique. The perforators were identified accurately by multidetector-row computed tomography preoperatively in all cases. This is the first report describing the application of multidetector-row computed tomography in the planning of propeller flaps. Multidetector-row computed tomography is superior to other imaging methods because it demonstrates more precisely the perforator's position and subcutaneous course using high-resolution three-dimensional images. By using multidetector-row computed tomography to preoperatively identify a flap's perforators, the surgeon can better plan the flap design to efficiently conduct the flap surgery.

Volumetric quantification of bone-implant contact using micro-computed tomography analysis based on region-based segmentation.

PubMed

Kang, Sung-Won; Lee, Woo-Jin; Choi, Soon-Chul; Lee, Sam-Sun; Heo, Min-Suk; Huh, Kyung-Hoe; Kim, Tae-Il; Yi, Won-Jin

2015-03-01

We have developed a new method of segmenting the areas of absorbable implants and bone using region-based segmentation of micro-computed tomography (micro-CT) images, which allowed us to quantify volumetric bone-implant contact (VBIC) and volumetric absorption (VA). The simple threshold technique generally used in micro-CT analysis cannot be used to segment the areas of absorbable implants and bone. Instead, a region-based segmentation method, a region-labeling method, and subsequent morphological operations were successively applied to micro-CT images. The three-dimensional VBIC and VA of the absorbable implant were then calculated over the entire volume of the implant. Two-dimensional (2D) bone-implant contact (BIC) and bone area (BA) were also measured based on the conventional histomorphometric method. VA and VBIC increased significantly with as the healing period increased (p<0.05). VBIC values were significantly correlated with VA values (p<0.05) and with 2D BIC values (p<0.05). It is possible to quantify VBIC and VA for absorbable implants using micro-CT analysis using a region-based segmentation method.

Death by 'ice': fatal methamphetamine intoxication of a body packer case detected by postmortem computed tomography (PMCT) and validated by autopsy.

PubMed

Bin Abdul Rashid, Saiful Nizam; Rahim, Amir Saad Abdul; Thali, Michael J; Flach, Patricia M

2013-03-01

Fatal acute methamphetamine (MA) poisoning in cases of internal drug trafficking is rarely described in the literature. This case study reports an MA 'body packer' who died from fatal methamphetamine intoxication due to leaking drug packages in the alimentary tract. The deceased was examined by postmortem computed tomography (PMCT), and the results were correlated to subsequent autopsy and toxicological findings. The deceased was arrested by the police when he was found disoriented in the city of Kuala Lumpur. He was transferred to the emergency department on suspicion of drug abuse. The initial drug screening was reactive for amphetamines. Shortly after admission to the hospital, he died despite rigorous resuscitation attempts. The postmortem plain chest and abdominal radiographs revealed multiple suspicious opacities in the gastrointestinal tract attributable to body packages. An unenhanced whole body PMCT revealed twenty-five drug packages, twenty-four in the stomach and one in the transverse colon. At least two were disintegrating, and therefore leaking. The autopsy findings were consistent with the PMCT results. Toxicology confirmed the diagnosis of fatal methamphetamine intoxication.

Advanced imaging technologies for mapping cadaveric lymphatic anatomy: magnetic resonance and computed tomography lymphangiography.

PubMed

Pan, W R; Rozen, W M; Stretch, J; Thierry, B; Ashton, M W; Corlett, R J

2008-09-01

Lymphatic anatomy has become increasingly clinically important as surgical techniques evolve for investigating and treating cancer metastases. However, due to limited anatomical techniques available, research in this field has been insufficient. The techniques of computed tomography (CT) and magnetic resonance (MR) lymphangiography have not been described previously in the imaging of cadaveric lymphatic anatomy. This preliminary work describes the feasibility of these advanced imaging technologies for imaging lymphatic anatomy. A single, fresh cadaveric lower limb underwent lymphatic dissection and cannulation utilizing microsurgical techniques. Contrast materials for both CT and MR studies were chosen based on their suitability for subsequent clinical use, and imaging was undertaken with a view to mapping lymphatic anatomy. Microdissection studies were compared with imaging findings in each case. Both MR-based and CT-based contrast media in current clinical use were found to be suitable for demonstrating cadaveric lymphatic anatomy upon direct intralymphatic injection. MR lymphangiography and CT lymphangiography are feasible modalities for cadaveric anatomical research for lymphatic anatomy. Future studies including refinements in scanning techniques may offer these technologies to the clinical setting.

Using computed tomography to assist with diagnosis of avascular necrosis complicating chronic scaphoid nonunion.

PubMed

Smith, Michael L; Bain, Gregory I; Chabrel, Nick; Turner, Perry; Carter, Chris; Field, John

2009-01-01

The primary aim of our study was to investigate use of long axis computed tomography (CT) in predicting avascular necrosis of the proximal pole of the scaphoid and subsequent fracture nonunion after internal fixation. In addition, we describe a new technique of measuring the position of a scaphoid fracture and provide data on its reproducibility. Thirty-one patients operated on by the senior author for delayed union or nonunion of scaphoid fracture were included. Preoperative CT scans were independently assessed for increased radiodensity of the proximal pole, converging trabeculae, degree of deformity, comminution, and fracture position. Intraoperative biopsies of the proximal pole were obtained and histologically assessed for evidence of avascular necrosis. The radiologic variables were statistically compared with the histologic findings. The presence of avascular necrosis was also compared with postoperative union status, identified on longitudinal CT scans. Preoperative CT features that statistically correlated with histologic evidence of avascular necrosis were increased radiodensity of the proximal pole and the absence of any converging trabeculae between the fracture fragments. The radiologic changes of avascular necrosis and the histologic confirmation of avascular necrosis were associated with persistent nonunion. Preoperative longitudinal CT of scaphoid nonunion is of great value in identifying avascular necrosis and predicting subsequent fracture union. If avascular necrosis is suspected based on preoperative CT, management options include vascularized bone grafts and bone morphogenic protein for younger patients and limited wrist arthrodesis for older patients. Diagnostic II.

Comparison of computed tomography and magnetic resonance imaging for the evaluation of canine intranasal neoplasia.

PubMed

Drees, R; Forrest, L J; Chappell, R

2009-07-01

Canine intranasal neoplasia is commonly evaluated using computed tomography to indicate the diagnosis, to determine disease extent, to guide histological sampling location and to plan treatment. With the expanding use of magnetic resonance imaging in veterinary medicine, this modality has been recently applied for the same purpose. The aim of this study was to compare the features of canine intranasal neoplasia using computed tomography and magnetic resonance imaging. Twenty-one dogs with confirmed intranasal neoplasia underwent both computed tomography and magnetic resonance imaging. The images were reviewed retrospectively for the bony and soft tissue features of intranasal neoplasia. Overall computed tomography and magnetic resonance imaging performed very similarly. However, lysis of bones bordering the nasal cavity and mucosal thickening was found on computed tomography images more often than on magnetic resonance images. Small amounts of fluid in the nasal cavity were more often seen on magnetic resonance images. However, fluid in the frontal sinuses was seen equally well with both modalities. We conclude that computed tomography is satisfactory for evaluation of canine intranasal neoplasia, and no clinically relevant benefit is gained using magnetic resonance imaging for intranasal neoplasia without extent into the cranial cavity.

Cone beam computed tomography in the diagnosis of dental disease.

PubMed

Tetradis, Sotirios; Anstey, Paul; Graff-Radford, Steven

2011-07-01

Conventional radiographs provide important information for dental disease diagnosis. However, they represent 2-D images of 3-D objects with significant structure superimposition and unpredictable magnification. Cone beam computed tomography, however, allows true 3-D visualization of the dentoalveolar structures, avoiding major limitations of conventional radiographs. Cone beam computed tomography images offer great advantages in disease detection for selected patients. The authors discuss cone beam computed tomography applications in dental disease diagnosis, reviewing the pertinent literature when available.

Detection of incidental colorectal pathology on positron emission tomography/computed tomography.

PubMed

Mui, Milton; Akhurst, Timothy; Warrier, Satish K; Lynch, A Craig; Heriot, Alexander G

2018-03-01

Positron emission tomography/computed tomography (PET/CT) is an important modality in cancer imaging. With its increasing availability and use, it is not uncommon to detect incidental focal colorectal 18 F-FDG uptake which poses a diagnostic challenge, as they may be associated with malignant or pre-malignant colorectal lesions. The aim of our study is to determine the proportion of these findings which represents true pathology. Patients with incidental focal colorectal 18 F-FDG uptake on PET/CT who subsequently underwent colonoscopy between January 2002 to September 2013 were identified from a prospective database in a tertiary referral centre. PET/CT results were correlated with colonoscopy and pathology results in these patients. Positive predictive values (PPVs) and 95% confidence intervals (CIs) of PET/CT in the detection of incidental colorectal pathology were calculated. A total of 148 patients (92 men and 56 women), with a mean age 73 years (range of 36 to 93 years) were included in the study. A total of 170 foci of colorectal 18 F-FDG uptake were detected on PET/CT. Of these, 101 foci corresponded to a malignant or pre-malignant lesion (PPV 59%; 95% CI: 52-67%). On a per-patient analysis, 93 patients had at least one focus of colorectal 18 F-FDG uptake which corresponded to a pre-malignant or malignant lesion (PPV 63%; 95% CI: 54-71%). Focal colorectal 18 F-FDG uptake on PET/CT is associated with a significant proportion of malignant or pre-malignant lesions. Further evaluation with colonoscopy is recommended. © 2016 Royal Australasian College of Surgeons.

Multiscale tomographic analysis of heterogeneous cast Al-Si-X alloys.

PubMed

Asghar, Z; Requena, G; Sket, F

2015-07-01

The three-dimensional microstructure of cast AlSi12Ni and AlSi10Cu5Ni2 alloys is investigated by laboratory X-ray computed tomography, synchrotron X-ray computed microtomography, light optical tomography and synchrotron X-ray computed microtomography with submicrometre resolution. The results obtained with each technique are correlated with the size of the scanned volumes and resolved microstructural features. Laboratory X-ray computed tomography is sufficient to resolve highly absorbing aluminides but eutectic and primary Si remain unrevealed. Synchrotron X-ray computed microtomography at ID15/ESRF gives better spatial resolution and reveals primary Si in addition to aluminides. Synchrotron X-ray computed microtomography at ID19/ESRF reveals all the phases ≥ ∼1 μm in volumes about 80 times smaller than laboratory X-ray computed tomography. The volumes investigated by light optical tomography and submicrometre synchrotron X-ray computed microtomography are much smaller than laboratory X-ray computed tomography but both techniques provide local chemical information on the types of aluminides. The complementary techniques applied enable a full three-dimensional characterization of the microstructure of the alloys at length scales ranging over six orders of magnitude. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

X-ray tomography system to investigate granular materials during mechanical loading

NASA Astrophysics Data System (ADS)

Athanassiadis, Athanasios G.; La Rivière, Patrick J.; Sidky, Emil; Pelizzari, Charles; Pan, Xiaochuan; Jaeger, Heinrich M.

2014-08-01

We integrate a small and portable medical x-ray device with mechanical testing equipment to enable in situ, non-invasive measurements of a granular material's response to mechanical loading. We employ an orthopedic C-arm as the x-ray source and detector to image samples mounted in the materials tester. We discuss the design of a custom rotation stage, which allows for sample rotation and tomographic reconstruction under applied compressive stress. We then discuss the calibration of the system for 3D computed tomography, as well as the subsequent image reconstruction process. Using this system to reconstruct packings of 3D-printed particles, we resolve packing features with 0.52 mm resolution in a (60 mm)3 field of view. By analyzing the performance bounds of the system, we demonstrate that the reconstructions exhibit only moderate noise.

Unusual Presentation of Bladder Paraganglioma: Comparison of (131)I MIBG SPECT/CT and (68)Ga DOTANOC PET/CT.

PubMed

Jain, Tarun Kumar; Basher, Rajender Kumar; Gupta, Nitin; Shukla, Jaya; Singh, Shrawan Kumar; Mittal, Bhagwant Rai

2016-01-01

Extraadrenal chromaffin cell-related tumors or paragangliomas are rare, especially in the bladder, accounting for less than 1% of cases. We report a 16-year-old boy who presented with hematuria and paroxysmal headache and was found to have a prostatic growth infiltrating the urinary bladder on anatomical imaging. Iodine-131 ((131)I) metaiodobenzylguanidine (MIBG) whole-body scanning and subsequently gallium-68 ((68)Ga) DOTANOC positron emission tomography/computed tomography (PET/CT) were performed. The MIBG scan revealed a non-tracer-avid soft-tissue mass, while DOTANOC PET/CT revealed a tracer-avid primary soft-tissue mass involving the urinary bladder and prostate with metastasis to the iliac lymph nodes. He underwent surgical management; histopathology of the surgical specimen revealed a bladder paraganglioma, whereas the prostate was found to be free of tumor.

Deformable image registration for multimodal lung-cancer staging

NASA Astrophysics Data System (ADS)

Cheirsilp, Ronnarit; Zang, Xiaonan; Bascom, Rebecca; Allen, Thomas W.; Mahraj, Rickhesvar P. M.; Higgins, William E.

2016-03-01

Positron emission tomography (PET) and X-ray computed tomography (CT) serve as major diagnostic imaging modalities in the lung-cancer staging process. Modern scanners provide co-registered whole-body PET/CT studies, collected while the patient breathes freely, and high-resolution chest CT scans, collected under a brief patient breath hold. Unfortunately, no method exists for registering a PET/CT study into the space of a high-resolution chest CT scan. If this could be done, vital diagnostic information offered by the PET/CT study could be brought seamlessly into the procedure plan used during live cancer-staging bronchoscopy. We propose a method for the deformable registration of whole-body PET/CT data into the space of a high-resolution chest CT study. We then demonstrate its potential for procedure planning and subsequent use in multimodal image-guided bronchoscopy.

Electromagnetic Navigational Bronchoscopy Reduces the Time Required for Localization and Resection of Lung Nodules.

PubMed

Bolton, William David; Cochran, Thomas; Ben-Or, Sharon; Stephenson, James E; Ellis, William; Hale, Allyson L; Binks, Andrew P

The aims of the study were to evaluate electromagnetic navigational bronchoscopy (ENB) and computed tomography-guided placement as localization techniques for minimally invasive resection of small pulmonary nodules and determine whether electromagnetic navigational bronchoscopy is a safer and more effective method than computed tomography-guided localization. We performed a retrospective review of our thoracic surgery database to identify patients who underwent minimally invasive resection for a pulmonary mass and used either electromagnetic navigational bronchoscopy or computed tomography-guided localization techniques between July 2011 and May 2015. Three hundred eighty-three patients had a minimally invasive resection during our study period, 117 of whom underwent electromagnetic navigational bronchoscopy or computed tomography localization (electromagnetic navigational bronchoscopy = 81; computed tomography = 36). There was no significant difference between computed tomography and electromagnetic navigational bronchoscopy patient groups with regard to age, sex, race, pathology, nodule size, or location. Both computed tomography and electromagnetic navigational bronchoscopy were 100% successful at localizing the mass, and there was no difference in the type of definitive surgical resection (wedge, segmentectomy, or lobectomy) (P = 0.320). Postoperative complications occurred in 36% of all patients, but there were no complications related to the localization procedures. In terms of localization time and surgical time, there was no difference between groups. However, the down/wait time between localization and resection was significant (computed tomography = 189 minutes; electromagnetic navigational bronchoscopy = 27 minutes); this explains why the difference in total time (sum of localization, down, and surgery) was significant (P < 0.001). We found electromagnetic navigational bronchoscopy to be as safe and effective as computed tomography-guided wire placement and to provide a significantly decreased down time between localization and surgical resection.

Sinonasal papilloma: what influences the decision to request a magnetic resonance imaging scan?

PubMed

Kasbekar, A V; Swords, C; Attlmayr, B; Kulkarni, T; Swift, A C

2018-06-18

Computed tomography is the standard pre-operative imaging modality for sinonasal papilloma. The complementary use of magnetic resonance imaging as an additional investigation is debated. This study aimed to establish whether magnetic resonance imaging can accurately detect tumour extent and is a useful adjunct to computed tomography. A retrospective review was conducted on 19 patients with sinonasal papilloma. The interpretation of computed tomography and magnetic resonance imaging scans, by three clinicians, was conducted by comparing prediction of tumour extent. The perceived necessity of magnetic resonance imaging was compared between clinicians. The addition of magnetic resonance imaging improved accuracy of pre-operative interpretation; specifically, this finding was significant in cases with frontal sinus involvement. Surgeons were more likely than a radiologist to request magnetic resonance imaging, particularly when computed tomography indicated frontal sinus disease. Pre-operative combined magnetic resonance imaging and computed tomography helped predict disease in the frontal sinus better than computed tomography alone. A close working relationship between the ENT and radiology departments is important for accurate tumour localisation.

Diagnostic Value of Software-Based Image Fusion of Computed Tomography and F18-FDG PET Scans in Patients with Malignant Lymphoma

PubMed Central

Henninger, B.; Putzer, D.; Kendler, D.; Uprimny, C.; Virgolini, I.; Gunsilius, E.; Bale, R.

2012-01-01

Aim. The purpose of this study was to evaluate the accuracy of 2-deoxy-2-[fluorine-18]fluoro-D-glucose (FDG) positron emission tomography (PET), computed tomography (CT), and software-based image fusion of both modalities in the imaging of non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD). Methods. 77 patients with NHL (n = 58) or HD (n = 19) underwent a FDG PET scan, a contrast-enhanced CT, and a subsequent digital image fusion during initial staging or followup. 109 examinations of each modality were evaluated and compared to each other. Conventional staging procedures, other imaging techniques, laboratory screening, and follow-up data constituted the reference standard for comparison with image fusion. Sensitivity and specificity were calculated for CT and PET separately. Results. Sensitivity and specificity for detecting malignant lymphoma were 90% and 76% for CT and 94% and 91% for PET, respectively. A lymph node region-based analysis (comprising 14 defined anatomical regions) revealed a sensitivity of 81% and a specificity of 97% for CT and 96% and 99% for FDG PET, respectively. Only three of 109 image fusion findings needed further evaluation (false positive). Conclusion. Digital fusion of PET and CT improves the accuracy of staging, restaging, and therapy monitoring in patients with malignant lymphoma and may reduce the need for invasive diagnostic procedures. PMID:22654631

Computer tomography of the neurocranium.

PubMed

Liliequist, B; Forssell, A

1976-07-01

The experience with computer tomography of the neurocranium in 300 patients submitted for computer tomography of the brain is reported. The more appropriate projections which may be obtained with the second generation of scanners in combination with an elaborated reconstruction technique seem to constitute a replacement of conventional skull films.

Study of Image Qualities From 6D Robot-Based CBCT Imaging System of Small Animal Irradiator.

PubMed

Sharma, Sunil; Narayanasamy, Ganesh; Clarkson, Richard; Chao, Ming; Moros, Eduardo G; Zhang, Xin; Yan, Yulong; Boerma, Marjan; Paudel, Nava; Morrill, Steven; Corry, Peter; Griffin, Robert J

2017-01-01

To assess the quality of cone beam computed tomography images obtained by a robotic arm-based and image-guided small animal conformal radiation therapy device. The small animal conformal radiation therapy device is equipped with a 40 to 225 kV X-ray tube mounted on a custom made gantry, a 1024 × 1024 pixels flat panel detector (200 μm resolution), a programmable 6 degrees of freedom robot for cone beam computed tomography imaging and conformal delivery of radiation doses. A series of 2-dimensional radiographic projection images were recorded in cone beam mode by placing and rotating microcomputed tomography phantoms on the "palm' of the robotic arm. Reconstructed images were studied for image quality (spatial resolution, image uniformity, computed tomography number linearity, voxel noise, and artifacts). Geometric accuracy was measured to be 2% corresponding to 0.7 mm accuracy on a Shelley microcomputed tomography QA phantom. Qualitative resolution of reconstructed axial computed tomography slices using the resolution coils was within 200 μm. Quantitative spatial resolution was found to be 3.16 lp/mm. Uniformity of the system was measured within 34 Hounsfield unit on a QRM microcomputed tomography water phantom. Computed tomography numbers measured using the linearity plate were linear with material density ( R 2 > 0.995). Cone beam computed tomography images of the QRM multidisk phantom had minimal artifacts. Results showed that the small animal conformal radiation therapy device is capable of producing high-quality cone beam computed tomography images for precise and conformal small animal dose delivery. With its high-caliber imaging capabilities, the small animal conformal radiation therapy device is a powerful tool for small animal research.

[Interest of MR perfusion and MR spectroscopy for the diagnostic of atypical cerebral toxoplasmosis].

PubMed

Barcelo, C; Catalaa, I; Loubes-Lacroix, F; Cognard, C; Bonneville, F

2010-03-01

We report an atypical case of cerebral toxoplasmosis (CT) in a 70-year-old woman with a history of breast cancer. Contrast-enhanced computed tomography revealed a single ring-enhancing lesion in the pons with perifocal oedema and mass effect. Toxoplasma encephalitis was suggested by means of diffusion weighted imaging, MR perfusion and MR spectroscopy, leading to the discovery of HIV infection. The patient was put on antitoxoplasma therapy. Subsequent clinical and radiological improvements confirmed the diagnosis. (c) 2009 Elsevier Masson SAS. All rights reserved.

ASSESSMENT OF VENOUS THROMBOSIS IN ANIMAL MODELS

PubMed Central

SP, Grover; CE, Evans; AS, Patel; B, Modarai; P, Saha; A, Smith

2016-01-01

Deep vein thrombosis and common complications, including pulmonary embolism and post thrombotic syndrome, represent a major source of morbidity and mortality worldwide. Experimental models of venous thrombosis have provided considerable insight into the cellular and molecular mechanisms that regulate thrombus formation and subsequent resolution. Here we critically appraise the ex vivo and in vivo techniques used to assess venous thrombosis in these models. Particular attention is paid to imaging modalities, including magnetic resonance imaging, micro computed tomography and high frequency ultrasound that facilitate longitudinal assessment of thrombus size and composition. PMID:26681755

Assessment of Venous Thrombosis in Animal Models.

PubMed

Grover, Steven P; Evans, Colin E; Patel, Ashish S; Modarai, Bijan; Saha, Prakash; Smith, Alberto

2016-02-01

Deep vein thrombosis and common complications, including pulmonary embolism and post-thrombotic syndrome, represent a major source of morbidity and mortality worldwide. Experimental models of venous thrombosis have provided considerable insight into the cellular and molecular mechanisms that regulate thrombus formation and subsequent resolution. Here, we critically appraise the ex vivo and in vivo techniques used to assess venous thrombosis in these models. Particular attention is paid to imaging modalities, including magnetic resonance imaging, micro-computed tomography, and high-frequency ultrasound that facilitate longitudinal assessment of thrombus size and composition. © 2015 American Heart Association, Inc.

Uteroenteric Fistula Resulting From Fibroid Expulsion After Uterine Fibroid Embolization: Case Report and Review of the Literature

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

Gutierrez, Luis B., E-mail: lbgutier@stanford.edu; Bansal, Anshuman K., E-mail: abansal@mednet.ucla.edu; Hovsepian, David M., E-mail: hovsepian@stanford.edu

A 44-year-old woman underwent uncomplicated uterine fibroid embolization (UFE) for menstrual and bulk-related symptoms in an enlarged, myomatous uterus. After surgery, she spontaneously sloughed a large mass of fibroids that arrested in the cervical canal during passage. Four days after gynecological extraction, she developed copious vaginal discharge that contained enteric contents. Contrast-enhanced computed tomography (CT) demonstrated a fistula between the small bowel and the uterus. She subsequently underwent hysterectomy, left oophorectomy, and small-bowel resection. Her postoperative recovery was uneventful.

Benefit from NASA

NASA Image and Video Library

2001-09-01

The high-tech art of digital signal processing (DSP) was pioneered at NASA's Jet Propulsion Laboratory (JPL) in the mid-1960s for use in the Apollo Lunar Landing Program. Designed to computer enhance pictures of the Moon, this technology became the basis for the Landsat Earth resources satellites and subsequently has been incorporated into a broad range of Earthbound medical and diagnostic tools. DSP is employed in advanced body imaging techniques including Computer-Aided Tomography, also known as CT and CATScan, and Magnetic Resonance Imaging (MRI). CT images are collected by irradiating a thin slice of the body with a fan-shaped x-ray beam from a number of directions around the body's perimeter. A tomographic (slice-like) picture is reconstructed from these multiple views by a computer. MRI employs a magnetic field and radio waves, rather than x-rays, to create images.

Morphometric analysis - Cone beam computed tomography to predict bone quality and quantity.

PubMed

Hohlweg-Majert, B; Metzger, M C; Kummer, T; Schulze, D

2011-07-01

Modified quantitative computed tomography is a method used to predict bone quality and quantify the bone mass of the jaw. The aim of this study was to determine whether bone quantity or quality was detected by cone beam computed tomography (CBCT) combined with image analysis. MATERIALS AND PROCEDURES: Different measurements recorded on two phantoms (Siemens phantom, Comac phantom) were evaluated on images taken with the Somatom VolumeZoom (Siemens Medical Solutions, Erlangen, Germany) and the NewTom 9000 (NIM s.r.l., Verona, Italy) in order to calculate a calibration curve. The spatial relationships of six sample cylinders and the repositioning from four pig skull halves relative to adjacent defined anatomical structures were assessed by means of three-dimensional visualization software. The calibration curves for computer tomography (CT) and cone beam computer tomography (CBCT) using the Siemens phantom showed linear correlation in both modalities between the Hounsfield Units (HU) and bone morphology. A correction factor for CBCT was calculated. Exact information about the micromorphology of the bone cylinders was only available using of micro computer tomography. Cone-beam computer tomography is a suitable choice for analysing bone mass, but, it does not give any information about bone quality. 2010 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Italian Chapter of the International Society of Cardiovascular Ultrasound expert consensus document on coronary computed tomography angiography: overview and new insights.

PubMed

Sozzi, Fabiola B; Maiello, Maria; Pelliccia, Francesco; Parato, Vito Maurizio; Canetta, Ciro; Savino, Ketty; Lombardi, Federico; Palmiero, Pasquale

2016-09-01

Coronary computed tomography angiography is a noninvasive heart imaging test currently undergoing rapid development and advancement. The high resolution of the three-dimensional pictures of the moving heart and great vessels is performed during a coronary computed tomography to identify coronary artery disease and classify patient risk for atherosclerotic cardiovascular disease. The technique provides useful information about the coronary tree and atherosclerotic plaques beyond simple luminal narrowing and plaque type defined by calcium content. This application will improve image-guided prevention, medical therapy, and coronary interventions. The ability to interpret coronary computed tomography images is of utmost importance as we develop personalized medical care to enable therapeutic interventions stratified on the bases of plaque characteristics. This overview provides available data and expert's recommendations in the utilization of coronary computed tomography findings. We focus on the use of coronary computed tomography to detect coronary artery disease and stratify patients at risk, illustrating the implications of this test on patient management. We describe its diagnostic power in identifying patients at higher risk to develop acute coronary syndrome and its prognostic significance. Finally, we highlight the features of the vulnerable plaques imaged by coronary computed tomography angiography. © 2016, Wiley Periodicals, Inc.

Comparison of computed tomography and magnetic resonance imaging for the evaluation of canine intranasal neoplasia

PubMed Central

Drees, R.; Forrest, L. J.; Chappell, R.

2009-01-01

Objectives Canine intranasal neoplasia is commonly evaluated using computed tomography to indicate the diagnosis, to determine disease extent, to guide histological sampling location and to plan treatment. With the expanding use of magnetic resonance imaging in veterinary medicine, this modality has been recently applied for the same purpose. The aim of this study was to compare the features of canine intranasal neoplasia using computed tomography and magnetic resonance imaging. Methods Twenty-one dogs with confirmed intranasal neoplasia underwent both computed tomography and magnetic resonance imaging. The images were reviewed retrospectively for the bony and soft tissue features of intranasal neoplasia. Results Overall computed tomography and magnetic resonance imaging performed very similarly. However, lysis of bones bordering the nasal cavity and mucosal thickening was found on computed tomography images more often than on magnetic resonance images. Small amounts of fluid in the nasal cavity were more often seen on magnetic resonance images. However, fluid in the frontal sinuses was seen equally well with both modalities. Clinical Significance We conclude that computed tomography is satisfactory for evaluation of canine intranasal neoplasia, and no clinically relevant benefit is gained using magnetic resonance imaging for intranasal neoplasia without extent into the cranial cavity. PMID:19508490

Measurement of Three-dimensional Density Distributions by Holographic Interferometry and Computer Tomography

NASA Technical Reports Server (NTRS)

Vest, C. M.

1982-01-01

The use of holographic interferometry to measure two and threedimensional flows and the interpretation of multiple-view interferograms with computer tomography are discussed. Computational techniques developed for tomography are reviewed. Current research topics are outlined including the development of an automated fringe readout system, optimum reconstruction procedures for when an opaque test model is present in the field, and interferometry and tomography with strongly refracting fields and shocks.

Computed tomography assessment of hip joints in asymptomatic individuals in relation to femoroacetabular impingement.

PubMed

Kang, Alan C L; Gooding, Andrew J; Coates, Mark H; Goh, Tony D; Armour, Paul; Rietveld, John

2010-06-01

Femoroacetabular impingement has become a well-recognized entity predisposing to acetabular labral tears and chondral damage, and subsequently development of osteoarthritis of the hip joint. In the authors' experience, it is common to see bony abnormalities predisposing to femoroacetabular impingement in the contralateral asymptomatic hips in patients with unilateral femoroacetabular impingement. This study was undertaken to investigate the prevalence of bony abnormalities predisposing to femoroacetabular impingement in asymptomatic individuals without exposing study participants to unnecessary radiation. Cross-sectional study; Level of evidence, 4. Fifty individuals (100 hip joints), ranging from 15 to 40 years of age, who were seen at a local hospital between March and August 2008 with abdominal trauma or nonspecific abdominal pain in whom abdominal computed tomography was performed to aid diagnosis were prospectively studied. These patients were not known to have any history of hip-related problems. Raw data from the abdominal computed tomography scan, performed on a 64-slice multidetector computed tomography scanner, were reformatted using bone algorithm into several different planes. Several measurements and observations of the hip joints were made in relation to femoroacetabular impingement. The 100 hip joints from 50 patients with no history of hip problems demonstrated that 39% of the joints (31% of female, 48% of male joints) have at least 1 morphologic aspect predisposing to femoroacetabular impingement. The majority (66% to 100% ) of the findings were bilateral; 33% of female and 52% of male asymptomatic participants in our study had at least 1 predisposing factor for femoroacetabular impingement in 1 or both of their hip joints. Based on the data collected from this study, the acetabular crossover sign had a 71% sensitivity and 88% specificity for detecting acetabular retroversion. Nonquantitative assessment of the femoral head at the anterior, anterolateral, and lateral head/neck junctions demonstrated that 74% of the joints had an aspherical femoral head. The study demonstrated substantial prevalence of bony characteristics predisposing to femoroacetabular impingement in asymptomatic individuals according to the established measurement parameters in current literature.

Severe brain atrophy after long-term survival seen in siblings with familial amyotrophic lateral sclerosis and a mutation in the optineurin gene: a case series.

PubMed

Ueno, Hiroki; Kobatake, Keitaro; Matsumoto, Masayasu; Morino, Hiroyuki; Maruyama, Hirofumi; Kawakami, Hideshi

2011-12-12

Previous studies have shown widespread multisystem degeneration in patients with sporadic amyotrophic lateral sclerosis who develop a total locked-in state and survive under mechanical ventilation for a prolonged period of time. However, the disease progressions reported in these studies were several years after disease onset. There have been no reports of long-term follow-up with brain imaging of patients with familial amyotrophic lateral sclerosis at an advanced stage of the disease. We report the cases of siblings with amyotrophic lateral sclerosis with homozygous deletions of the exon 5 mutation of the gene encoding optineurin, in whom brain computed tomography scans were followed up for more than 20 years. The patients were a Japanese brother and sister. The elder sister was 33 years of age at the onset of disease, which began with muscle weakness of her left lower limb. Two years later she required mechanical ventilation. She became bedridden at the age of 34, and died at the age of 57. A computed tomography scan of her brain at the age of 36 revealed no abnormality. Atrophy of her brain gradually progressed. Ten years after the onset of mechanical ventilation, atrophy of her whole brain, including the cerebral cortex, brain stem and cerebellum, markedly progressed. Her younger brother was 36 years of age at the onset of disease, which presented as muscle weakness of his left upper limb. One year later, he showed dysphagia and dysarthria, and tracheostomy ventilation was performed. He became bedridden at the age of 37 and died at the age of 55. There were no abnormal intracranial findings on brain computed tomography scans obtained at the age of 37 years. At the age of 48 years, computed tomography scans showed marked brain atrophy with ventricular dilatation. Subsequently, atrophy of the whole brain rapidly progressed as in his elder sister. We conclude that a homozygous deletion-type mutation in the optineurin gene may be associated with widespread multisystem degeneration in amyotrophic lateral sclerosis.

Improving early diagnosis of pulmonary infections in patients with febrile neutropenia using low-dose chest computed tomography.

PubMed

Gerritsen, M G; Willemink, M J; Pompe, E; van der Bruggen, T; van Rhenen, A; Lammers, J W J; Wessels, F; Sprengers, R W; de Jong, P A; Minnema, M C

2017-01-01

We performed a prospective study in patients with chemotherapy induced febrile neutropenia to investigate the diagnostic value of low-dose computed tomography compared to standard chest radiography. The aim was to compare both modalities for detection of pulmonary infections and to explore performance of low-dose computed tomography for early detection of invasive fungal disease. The low-dose computed tomography remained blinded during the study. A consensus diagnosis of the fever episode made by an expert panel was used as reference standard. We included 67 consecutive patients on the first day of febrile neutropenia. According to the consensus diagnosis 11 patients (16.4%) had pulmonary infections. Sensitivity, specificity, positive predictive value and negative predictive value were 36%, 93%, 50% and 88% for radiography, and 73%, 91%, 62% and 94% for low-dose computed tomography, respectively. An uncorrected McNemar showed no statistical difference (p = 0.197). Mean radiation dose for low-dose computed tomography was 0.24 mSv. Four out of 5 included patients diagnosed with invasive fungal disease had radiographic abnormalities suspect for invasive fungal disease on the low-dose computed tomography scan made on day 1 of fever, compared to none of the chest radiographs. We conclude that chest radiography has little value in the initial assessment of febrile neutropenia on day 1 for detection of pulmonary abnormalities. Low-dose computed tomography improves detection of pulmonary infiltrates and seems capable of detecting invasive fungal disease at a very early stage with a low radiation dose.

Improving early diagnosis of pulmonary infections in patients with febrile neutropenia using low-dose chest computed tomography

PubMed Central

Pompe, E.; van der Bruggen, T.; van Rhenen, A.; Lammers, J. W. J.; Wessels, F.; Sprengers, R. W.; de Jong, P. A.; Minnema, M. C.

2017-01-01

We performed a prospective study in patients with chemotherapy induced febrile neutropenia to investigate the diagnostic value of low-dose computed tomography compared to standard chest radiography. The aim was to compare both modalities for detection of pulmonary infections and to explore performance of low-dose computed tomography for early detection of invasive fungal disease. The low-dose computed tomography remained blinded during the study. A consensus diagnosis of the fever episode made by an expert panel was used as reference standard. We included 67 consecutive patients on the first day of febrile neutropenia. According to the consensus diagnosis 11 patients (16.4%) had pulmonary infections. Sensitivity, specificity, positive predictive value and negative predictive value were 36%, 93%, 50% and 88% for radiography, and 73%, 91%, 62% and 94% for low-dose computed tomography, respectively. An uncorrected McNemar showed no statistical difference (p = 0.197). Mean radiation dose for low-dose computed tomography was 0.24 mSv. Four out of 5 included patients diagnosed with invasive fungal disease had radiographic abnormalities suspect for invasive fungal disease on the low-dose computed tomography scan made on day 1 of fever, compared to none of the chest radiographs. We conclude that chest radiography has little value in the initial assessment of febrile neutropenia on day 1 for detection of pulmonary abnormalities. Low-dose computed tomography improves detection of pulmonary infiltrates and seems capable of detecting invasive fungal disease at a very early stage with a low radiation dose. PMID:28235014

Real-time data-intensive computing

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

Parkinson, Dilworth Y., E-mail: dyparkinson@lbl.gov; Chen, Xian; Hexemer, Alexander

2016-07-27

Today users visit synchrotrons as sources of understanding and discovery—not as sources of just light, and not as sources of data. To achieve this, the synchrotron facilities frequently provide not just light but often the entire end station and increasingly, advanced computational facilities that can reduce terabytes of data into a form that can reveal a new key insight. The Advanced Light Source (ALS) has partnered with high performance computing, fast networking, and applied mathematics groups to create a “super-facility”, giving users simultaneous access to the experimental, computational, and algorithmic resources to make this possible. This combination forms an efficientmore » closed loop, where data—despite its high rate and volume—is transferred and processed immediately and automatically on appropriate computing resources, and results are extracted, visualized, and presented to users or to the experimental control system, both to provide immediate insight and to guide decisions about subsequent experiments during beamtime. We will describe our work at the ALS ptychography, scattering, micro-diffraction, and micro-tomography beamlines.« less

Nasal computed tomography.

PubMed

Kuehn, Ned F

2006-05-01

Chronic nasal disease is often a challenge to diagnose. Computed tomography greatly enhances the ability to diagnose chronic nasal disease in dogs and cats. Nasal computed tomography provides detailed information regarding the extent of disease, accurate discrimination of neoplastic versus nonneoplastic diseases, and identification of areas of the nose to examine rhinoscopically and suspicious regions to target for biopsy.

Multislice Computed Tomography Accurately Detects Stenosis in Coronary Artery Bypass Conduits

PubMed Central

Duran, Cihan; Sagbas, Ertan; Caynak, Baris; Sanisoglu, Ilhan; Akpinar, Belhhan; Gulbaran, Murat

2007-01-01

The aim of this study was to evaluate the accuracy of multislice computed tomography in detecting graft stenosis or occlusion after coronary artery bypass grafting, using coronary angiography as the standard. From January 2005 through May 2006, 25 patients (19 men and 6 women; mean age, 54 ± 11.3 years) underwent diagnostic investigation of their bypass grafts by multislice computed tomography within 1 month of coronary angiography. The mean time elapsed after coronary artery bypass grafting was 6.2 years. In these 25 patients, we examined 65 bypass conduits (24 arterial and 41 venous) and 171 graft segments (the shaft, proximal anastomosis, and distal anastomosis). Compared with coronary angiography, the segment-based sensitivity, specificity, and positive and negative predictive values of multislice computed tomography in the evaluation of stenosis were 89%, 100%, 100%, and 99%, respectively. The patency rate for multislice compu-ted tomography was 85% (55/65: 3 arterial and 7 venous grafts were occluded), with 100% sensitivity and specificity. From these data, we conclude that multislice computed tomography can accurately evaluate the patency and stenosis of bypass grafts during outpatient follow-up. PMID:17948078

Differences between postmortem computed tomography and conventional autopsy in a stabbing murder case

PubMed Central

Zerbini, Talita; da Silva, Luiz Fernando Ferraz; Ferro, Antonio Carlos Gonçalves; Kay, Fernando Uliana; Junior, Edson Amaro; Pasqualucci, Carlos Augusto Gonçalves; do Nascimento Saldiva, Paulo Hilario

2014-01-01

OBJECTIVE: The aim of the present work is to analyze the differences and similarities between the elements of a conventional autopsy and images obtained from postmortem computed tomography in a case of a homicide stab wound. METHOD: Comparison between the findings of different methods: autopsy and postmortem computed tomography. RESULTS: In some aspects, autopsy is still superior to imaging, especially in relation to external examination and the description of lesion vitality. However, the findings of gas embolism, pneumothorax and pulmonary emphysema and the relationship between the internal path of the instrument of aggression and the entry wound are better demonstrated by postmortem computed tomography. CONCLUSIONS: Although multislice computed tomography has greater accuracy than autopsy, we believe that the conventional autopsy method is fundamental for providing evidence in criminal investigations. PMID:25518020

Interlaced X-ray diffraction computed tomography

PubMed Central

Vamvakeros, Antonios; Jacques, Simon D. M.; Di Michiel, Marco; Senecal, Pierre; Middelkoop, Vesna; Cernik, Robert J.; Beale, Andrew M.

2016-01-01

An X-ray diffraction computed tomography data-collection strategy that allows, post experiment, a choice between temporal and spatial resolution is reported. This strategy enables time-resolved studies on comparatively short timescales, or alternatively allows for improved spatial resolution if the system under study, or components within it, appear to be unchanging. The application of the method for studying an Mn–Na–W/SiO2 fixed-bed reactor in situ is demonstrated. Additionally, the opportunities to improve the data-collection strategy further, enabling post-collection tuning between statistical, temporal and spatial resolutions, are discussed. In principle, the interlaced scanning approach can also be applied to other pencil-beam tomographic techniques, like X-ray fluorescence computed tomography, X-ray absorption fine structure computed tomography, pair distribution function computed tomography and tomographic scanning transmission X-ray microscopy. PMID:27047305

Colovesical fistula causing an uncommon reason for failure of computed tomography colonography: a case report.

PubMed

Neroladaki, Angeliki; Breguet, Romain; Botsikas, Diomidis; Terraz, Sylvain; Becker, Christoph D; Montet, Xavier

2012-07-23

Computed tomography colonography, or virtual colonoscopy, is a good alternative to optical colonoscopy. However, suboptimal patient preparation or colon distension may reduce the diagnostic accuracy of this imaging technique. We report the case of an 83-year-old Caucasian woman who presented with a five-month history of pneumaturia and fecaluria and an acute episode of macrohematuria, leading to a high clinical suspicion of a colovesical fistula. The fistula was confirmed by standard contrast-enhanced computed tomography. Optical colonoscopy was performed to exclude the presence of an underlying colonic neoplasm. Since optical colonoscopy was incomplete, computed tomography colonography was performed, but also failed due to inadequate colon distension. The insufflated air directly accumulated within the bladder via the large fistula. Clinicians should consider colovesical fistula as a potential reason for computed tomography colonography failure.

Computed tomography and (18)F-fluorodeoxyglucose positron emission tomography/computed tomography findings in adrenal candidiasis and histoplasmosis: two cases.

PubMed

Altinmakas, Emre; Guo, Ming; Kundu, Uma R; Habra, Mouhammed Amir; Ng, Chaan

2015-01-01

We report the contrast-enhanced computed tomography (CT) and (18)F-fluorodeoxyglucose positron emission tomography findings in adrenal histoplasmosis and candidiasis. Both demonstrated bilateral hypermetabolic heterogeneous adrenal masses with limited wash-out on delayed CT. Adrenal candidiasis has not been previously reported, nor have the CT wash-out findings in either infection. The adrenal imaging findings are indistinguishable from malignancy, which is more common; but in this setting, physicians should be alert to the differential diagnosis of fungal infections, since it can be equally deadly. Published by Elsevier Inc.

Incidental renal tumours on low-dose CT lung cancer screening exams.

PubMed

Pinsky, Paul F; Dunn, Barbara; Gierada, David; Nath, P Hrudaya; Munden, Reginald; Berland, Lincoln; Kramer, Barnett S

2017-06-01

Introduction Renal cancer incidence has increased markedly in the United States in recent decades, largely due to incidentally detected tumours from computed tomography imaging. Here, we analyze the potential for low-dose computed tomography lung cancer screening to detect renal cancer. Methods The National Lung Screening Trial randomized subjects to three annual screens with either low-dose computed tomography or chest X-ray. Eligibility criteria included 30 + pack-years, current smoking or quit within 15 years, and age 55-74. Subjects were followed for seven years. Low-dose computed tomography screening forms collected information on lung cancer and non-lung cancer abnormalities, including abnormalities below the diaphragm. A reader study was performed on a sample of National Lung Screening Trial low-dose computed tomography images assessing presence of abnormalities below the diaphragms and abnormalities suspicious for renal cancer. Results There were 26,722 and 26,732 subjects enrolled in the low-dose computed tomography and chest X-ray arms, respectively, and there were 104 and 85 renal cancer cases diagnosed, respectively (relative risk = 1.22, 95% CI: 0.9-1.5). From 75,126 low-dose computed tomography screens, there were 46 renal cancer diagnoses within one year. Abnormalities below the diaphragm rates were 39.1% in screens with renal cancer versus 4.1% in screens without (P < 0.001). Cases with abnormalities below the diaphragms had shorter median time to diagnosis than those without (71 vs. 160 days, P = 0.004). In the reader study, 64% of renal cancer cases versus 13% of non-cases had abnormalities below the diaphragms; 55% of cases and 0.8% of non-cases had a finding suspicious for renal cancer (P < 0.001). Conclusion Low-dose computed tomography screens can potentially detect renal cancers. The benefits to harms tradeoff of incidental detection of renal tumours on low-dose computed tomography is unknown.

Meta-Analysis of Stress Myocardial Perfusion Imaging

ClinicalTrials.gov

2017-06-06

Coronary Disease; Echocardiography; Fractional Flow Reserve, Myocardial; Hemodynamics; Humans; Magnetic Resonance Imaging; Myocardial Perfusion Imaging; Perfusion; Predictive Value of Tests; Single Photon Emission Computed Tomography; Positron Emission Tomography; Multidetector Computed Tomography; Echocardiography, Stress; Coronary Angiography

Positron Computed Tomography: Current State, Clinical Results and Future Trends

DOE R&D Accomplishments Database

Schelbert, H. R.; Phelps, M. E.; Kuhl, D. E.

1980-09-01

An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends. (ACR)

Diagnostic dilemma of degenerative joint disease, chronic avascular necrosis or metastasis in planar Tc-99m-methylene diphosphonate planar skeletal scintigraphy excluded by single positron emission computed tomography/computed tomography.

PubMed

Jain, Tarun Kumar; Phulsunga, Rohit Kumar; Basher, Rajender Kumar; Kumar, Narendra; Bhattacharya, Anish; Mittal, Bhagwant Rai

2015-01-01

We present a 71-year-old male patient subjected to skeletal scintigraphy for metastasis work up of prostate cancer. Whole body planar images revealed a solitary focal tracer uptake in left femoral head mimicking as solitary metastatic focus. Single positron emission computed tomography/computed tomography images localized this increased tracer uptake to the subchondral cysts with minimal sclerosis in left femur head with no decrease in size of femur head and was reported as (degenerative joint disease).

Diagnostic dilemma of degenerative joint disease, chronic avascular necrosis or metastasis in planar Tc-99m-methylene diphosphonate planar skeletal scintigraphy excluded by single positron emission computed tomography/computed tomography

PubMed Central

Jain, Tarun Kumar; Phulsunga, Rohit Kumar; Basher, Rajender Kumar; Kumar, Narendra; Bhattacharya, Anish; Mittal, Bhagwant Rai

2015-01-01

We present a 71-year-old male patient subjected to skeletal scintigraphy for metastasis work up of prostate cancer. Whole body planar images revealed a solitary focal tracer uptake in left femoral head mimicking as solitary metastatic focus. Single positron emission computed tomography/computed tomography images localized this increased tracer uptake to the subchondral cysts with minimal sclerosis in left femur head with no decrease in size of femur head and was reported as (degenerative joint disease). PMID:26170582

The early development of medial coronoid disease in growing Labrador retrievers: radiographic, computed tomographic, necropsy and micro-computed tomographic findings.

PubMed

Lau, S F; Wolschrijn, C F; Hazewinkel, H A W; Siebelt, M; Voorhout, G

2013-09-01

Medial coronoid disease (MCD) encompasses lesions of the entire medial coronoid process (MCP), both of the articular cartilage and the subchondral bone. To detect the earliest signs of MCD, radiography and computed tomography were used to monitor the development of MCD in 14 Labrador retrievers, from 6 to 7 weeks of age until euthanasia. The definitive diagnosis of MCD was based on necropsy and micro-computed tomography findings. The frequency of MCD in the dogs studied was 50%. Radiographic findings did not provide evidence of MCD, ulnar subtrochlear sclerosis or blunting of the cranial edge of the MCP. Computed tomography was more sensitive (30.8%) than radiography (0%) in detecting early MCD, with the earliest signs detectable at 14 weeks of age. A combination of the necropsy and micro-computed tomography findings of the MCP showed that MCD was manifested as a lesion of only the subchondral bone in dogs <18 weeks of age. In all dogs (affected and unaffected), there was close contact between the base of the MCP and the proximal radial head in the congruent joints. Computed tomography and micro-computed tomography findings indicated that the lesions of MCD probably originated at the base of the MCP. Copyright © 2013 Elsevier Ltd. All rights reserved.

X-ray tomography system to investigate granular materials during mechanical loading

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

Athanassiadis, Athanasios G.; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139; La Rivière, Patrick J.

2014-08-15

We integrate a small and portable medical x-ray device with mechanical testing equipment to enable in situ, non-invasive measurements of a granular material's response to mechanical loading. We employ an orthopedic C-arm as the x-ray source and detector to image samples mounted in the materials tester. We discuss the design of a custom rotation stage, which allows for sample rotation and tomographic reconstruction under applied compressive stress. We then discuss the calibration of the system for 3D computed tomography, as well as the subsequent image reconstruction process. Using this system to reconstruct packings of 3D-printed particles, we resolve packing featuresmore » with 0.52 mm resolution in a (60 mm){sup 3} field of view. By analyzing the performance bounds of the system, we demonstrate that the reconstructions exhibit only moderate noise.« less

A partially reflecting random walk on spheres algorithm for electrical impedance tomography

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

Maire, Sylvain, E-mail: maire@univ-tln.fr; Simon, Martin, E-mail: simon@math.uni-mainz.de

2015-12-15

In this work, we develop a probabilistic estimator for the voltage-to-current map arising in electrical impedance tomography. This novel so-called partially reflecting random walk on spheres estimator enables Monte Carlo methods to compute the voltage-to-current map in an embarrassingly parallel manner, which is an important issue with regard to the corresponding inverse problem. Our method uses the well-known random walk on spheres algorithm inside subdomains where the diffusion coefficient is constant and employs replacement techniques motivated by finite difference discretization to deal with both mixed boundary conditions and interface transmission conditions. We analyze the global bias and the variance ofmore » the new estimator both theoretically and experimentally. Subsequently, the variance of the new estimator is considerably reduced via a novel control variate conditional sampling technique which yields a highly efficient hybrid forward solver coupling probabilistic and deterministic algorithms.« less

Unusual Presentation of Bladder Paraganglioma: Comparison of 131I MIBG SPECT/CT and 68Ga DOTANOC PET/CT

PubMed Central

Jain, Tarun Kumar; Basher, Rajender Kumar; Gupta, Nitin; Shukla, Jaya; Singh, Shrawan Kumar; Mittal, Bhagwant Rai

2016-01-01

Extraadrenal chromaffin cell-related tumors or paragangliomas are rare, especially in the bladder, accounting for less than 1% of cases. We report a 16-year-old boy who presented with hematuria and paroxysmal headache and was found to have a prostatic growth infiltrating the urinary bladder on anatomical imaging. Iodine-131 (131I) metaiodobenzylguanidine (MIBG) whole-body scanning and subsequently gallium-68 (68Ga) DOTANOC positron emission tomography/computed tomography (PET/CT) were performed. The MIBG scan revealed a non-tracer-avid soft-tissue mass, while DOTANOC PET/CT revealed a tracer-avid primary soft-tissue mass involving the urinary bladder and prostate with metastasis to the iliac lymph nodes. He underwent surgical management; histopathology of the surgical specimen revealed a bladder paraganglioma, whereas the prostate was found to be free of tumor. PMID:26912984

A feasibility study of X-ray phase-contrast mammographic tomography at the Imaging and Medical beamline of the Australian Synchrotron.

PubMed

Nesterets, Yakov I; Gureyev, Timur E; Mayo, Sheridan C; Stevenson, Andrew W; Thompson, Darren; Brown, Jeremy M C; Kitchen, Marcus J; Pavlov, Konstantin M; Lockie, Darren; Brun, Francesco; Tromba, Giuliana

2015-11-01

Results are presented of a recent experiment at the Imaging and Medical beamline of the Australian Synchrotron intended to contribute to the implementation of low-dose high-sensitivity three-dimensional mammographic phase-contrast imaging, initially at synchrotrons and subsequently in hospitals and medical imaging clinics. The effect of such imaging parameters as X-ray energy, source size, detector resolution, sample-to-detector distance, scanning and data processing strategies in the case of propagation-based phase-contrast computed tomography (CT) have been tested, quantified, evaluated and optimized using a plastic phantom simulating relevant breast-tissue characteristics. Analysis of the data collected using a Hamamatsu CMOS Flat Panel Sensor, with a pixel size of 100 µm, revealed the presence of propagation-based phase contrast and demonstrated significant improvement of the quality of phase-contrast CT imaging compared with conventional (absorption-based) CT, at medically acceptable radiation doses.

Tomography in Geology: 3D Modeling and Analysis of Structural Features of Rocks Using Computed MicroTomography

NASA Astrophysics Data System (ADS)

Ponomarev, A. A.; Mamadaliev, R. A.; Semenova, T. V.

2016-10-01

The article presents a brief overview of the current state of computed tomography in the sphere of oil and gas production in Russia and in the world. Operation of computed microtomograph Skyscan 1172 is also provided, as well as personal examples of its application in solving geological problems.

Aerosolized intranasal midazolam for safe and effective sedation for quality computed tomography imaging in infants and children.

PubMed

Mekitarian Filho, Eduardo; de Carvalho, Werther Brunow; Gilio, Alfredo Elias; Robinson, Fay; Mason, Keira P

2013-10-01

This pilot study introduces the aerosolized route for midazolam as an option for infant and pediatric sedation for computed tomography imaging. This technique produced predictable and effective sedation for quality computed tomography imaging studies with minimal artifact and no significant adverse events. Copyright © 2013 Mosby, Inc. All rights reserved.

Computed Tomography Measuring Inside Machines

NASA Technical Reports Server (NTRS)

Wozniak, James F.; Scudder, Henry J.; Anders, Jeffrey E.

1995-01-01

Computed tomography applied to obtain approximate measurements of radial distances from centerline of turbopump to leading edges of diffuser vanes in turbopump. Use of computed tomography has significance beyond turbopump application: example of general concept of measuring internal dimensions of assembly of parts without having to perform time-consuming task of taking assembly apart and measuring internal parts on coordinate-measuring machine.

A Heat Pipe Coupled Planar Thermionic Converter: Performance Characterization, Nondestructive Testing, and Evaluation.

DTIC Science & Technology

1992-03-15

Pipes, Computer Modelling, Nondestructive Testing. Tomography , Planar Converter, Cesium Reservoir 19. ABSTRACT (Continue on reverse if necessary and...Investigation ........................ 32 4.3 Computed Tomography ................................ 33 4.4 X-Ray Radiography...25 3.4 LEOS generated output data for Mo-Re converter ................ 26 4.1 Distance along converter imaged by the computed tomography

SPECT/CT localization of oral radioiodine activity: a retrospective study and in-vitro assessment.

PubMed

Burlison, Jared S; Hartshorne, Michael F; Voda, Alan M; Cocks, Franklin H; Fair, Joanna R

2013-12-01

We sought to further localize radioiodine activity in the mouth on post-thyroid cancer therapy imaging using single-photon emission computed tomography/computed tomography (SPECT/CT). We retrospectively reviewed all patients (58) who underwent thyroid cancer therapy with iodine-131 (131I) at our institution from August 2009 to March 2011 whose post-therapy radioiodine imaging included neck SPECT/CT. A small group (six) of diagnostic 131I scans including SPECT/CT was also reviewed. Separately, we performed in-vitro 131I (sodium iodide) binding assays with amalgam and Argenco HP 77 (77% dental gold alloy) as proof of principle for these interactions. Of the 58 post-therapy patients, 45 (78%) had undergone metallic dental restorations, and of them 41 (91%) demonstrated oral 131I activity localizing preferentially to those restorations. It was observed that radioiodine also localized to other dental restorations and to orthodontic hardware. Gum-line activity in edentulous patients suggests radioiodine interaction with denture adhesive. In vitro, dental amalgam and Argenco HP 77 bound 131I in a time-dependent manner over 1-16 days of exposure. Despite subsequent washings with normal saline, significant 131I activity (maximally 12% for amalgam and 68% for Argenco HP 77) was retained by these metals. Subsequent soaking in a saturated solution of potassium iodide partially displaced 131I from amalgam, with near-total displacement of I from Argenco HP 77. SPECT/CT shows that radioiodine in the oral cavity localizes to metallic dental restorations. Furthermore, in-vitro studies demonstrate partially reversible binding of 131I to common dental metals.

Nondestructive microimaging during preclinical pin-on-plate testing of novel materials for arthroplasty.

PubMed

Teeter, Matthew G; Langohr, G Daniel G; Medley, John B; Holdsworth, David W

2014-02-01

The purpose of this study was to determine the ability of micro-computed tomography to quantify wear in preclinical pin-on-plate testing of materials for use in joint arthroplasty. Wear testing of CoCr pins articulating against six polyetheretherketone plates was performed using a pin-on-plate apparatus over 2 million cycles. Change in volume due to wear was quantified with gravimetric analysis and with micro-computed tomography, and the volumes were compared. Separately, the volume of polyetheretherketone pin-on-plate specimens that had been soaking in fluid for 52 weeks was quantified with both gravimetric analysis and micro-computed tomography, and repeated after drying. The volume change with micro-computed tomography was compared to the mass change with gravimetric analysis. The mean wear volume measured was 8.02 ± 6.38 mm(3) with gravimetric analysis and 6.76 ± 5.38 mm(3) with micro-computed tomography (p = 0.06). Micro-computed tomography volume measurements did not show a statistically significant change with drying for either the plates (p = 0.60) or the pins (p = 0.09), yet drying had a significant effect on the gravimetric mass measurements for both the plates (p = 0.03) and the pins (p = 0.04). Micro-computed tomography provided accurate measurements of wear in polyetheretherketone pin-on-plate test specimens, and no statistically significant change was caused by fluid uptake. Micro-computed tomography quantifies wear depth and wear volume, mapped to the specific location of damage on the specimen, and is also capable of examining subsurface density as well as cracking. Its noncontact, nondestructive nature makes it ideal for preclinical testing of materials, in which further additional analysis techniques may be utilized.

Preoperative (3-dimensional) computed tomography lung reconstruction before anatomic segmentectomy or lobectomy for stage I non-small cell lung cancer.

PubMed

Chan, Ernest G; Landreneau, James R; Schuchert, Matthew J; Odell, David D; Gu, Suicheng; Pu, Jiantao; Luketich, James D; Landreneau, Rodney J

2015-09-01

Accurate cancer localization and negative resection margins are necessary for successful segmentectomy. In this study, we evaluate a newly developed software package that permits automated segmentation of the pulmonary parenchyma, allowing 3-dimensional assessment of tumor size, location, and estimates of surgical margins. A pilot study using a newly developed 3-dimensional computed tomography analytic software package was performed to retrospectively evaluate preoperative computed tomography images of patients who underwent segmentectomy (n = 36) or lobectomy (n = 15) for stage 1 non-small cell lung cancer. The software accomplishes an automated reconstruction of anatomic pulmonary segments of the lung based on bronchial arborization. Estimates of anticipated surgical margins and pulmonary segmental volume were made on the basis of 3-dimensional reconstruction. Autosegmentation was achieved in 72.7% (32/44) of preoperative computed tomography images with slice thicknesses of 3 mm or less. Reasons for segmentation failure included local severe emphysema or pneumonitis, and lower computed tomography resolution. Tumor segmental localization was achieved in all autosegmented studies. The 3-dimensional computed tomography analysis provided a positive predictive value of 87% in predicting a marginal clearance greater than 1 cm and a 75% positive predictive value in predicting a margin to tumor diameter ratio greater than 1 in relation to the surgical pathology assessment. This preoperative 3-dimensional computed tomography analysis of segmental anatomy can confirm the tumor location within an anatomic segment and aid in predicting surgical margins. This 3-dimensional computed tomography information may assist in the preoperative assessment regarding the suitability of segmentectomy for peripheral lung cancers. Published by Elsevier Inc.

Role of post-mapping computed tomography in virtual-assisted lung mapping.

PubMed

Sato, Masaaki; Nagayama, Kazuhiro; Kuwano, Hideki; Nitadori, Jun-Ichi; Anraku, Masaki; Nakajima, Jun

2017-02-01

Background Virtual-assisted lung mapping is a novel bronchoscopic preoperative lung marking technique in which virtual bronchoscopy is used to predict the locations of multiple dye markings. Post-mapping computed tomography is performed to confirm the locations of the actual markings. This study aimed to examine the accuracy of marking locations predicted by virtual bronchoscopy and elucidate the role of post-mapping computed tomography. Methods Automated and manual virtual bronchoscopy was used to predict marking locations. After bronchoscopic dye marking under local anesthesia, computed tomography was performed to confirm the actual marking locations before surgery. Discrepancies between marking locations predicted by the different methods and the actual markings were examined on computed tomography images. Forty-three markings in 11 patients were analyzed. Results The average difference between the predicted and actual marking locations was 30 mm. There was no significant difference between the latest version of the automated virtual bronchoscopy system (30.7 ± 17.2 mm) and manual virtual bronchoscopy (29.8 ± 19.1 mm). The difference was significantly greater in the upper vs. lower lobes (37.1 ± 20.1 vs. 23.0 ± 6.8 mm, for automated virtual bronchoscopy; p < 0.01). Despite this discrepancy, all targeted lesions were successfully resected using 3-dimensional image guidance based on post-mapping computed tomography reflecting the actual marking locations. Conclusions Markings predicted by virtual bronchoscopy were dislocated from the actual markings by an average of 3 cm. However, surgery was accurately performed using post-mapping computed tomography guidance, demonstrating the indispensable role of post-mapping computed tomography in virtual-assisted lung mapping.

Utility of screening computed tomography of chest, abdomen and pelvis in patients after heart transplantation.

PubMed

Dasari, Tarun W; Pavlovic-Surjancev, Biljana; Dusek, Linda; Patel, Nilamkumar; Heroux, Alain L

2011-12-01

Malignancy is a late cause of mortality in heart transplant recipients. It is unknown if screening computed tomography scan would lead to early detection of such malignancies or serious vascular anomalies post heart transplantation. This is a single center observational study of patients undergoing surveillance computed tomography of chest, abdomen and pelvis at least 5 years after transplantation. Abnormal findings, included pulmonary nodules, lymphadenopathy and intra-thoracic and intra-abdominal masses and vascular anomalies such as abdominal aortic aneurysm. The clinical follow up of each of these major abnormal findings is summarized. A total of 63 patients underwent computed tomography scan of chest, abdomen and pelvis at least 5 years after transplantation. Of these, 54 (86%) were male and 9 (14%) were female. Mean age was 52±9.2 years. Computed tomography revealed 1 lung cancer (squamous cell) only. Non specific pulmonary nodules were seen in 6 patients (9.5%). The most common incidental finding was abdominal aortic aneurysms (N=6 (9.5%)), which necessitated follow up computed tomography (N=5) or surgery (N=1). Mean time to detection of abdominal aortic aneurysms from transplantation was 14.6±4.2 years. Mean age at the time of detection of abdominal aortic aneurysms was 74.5±3.2 years. Screening computed tomography scan in patients 5 years from transplantation revealed only one malignancy but lead to increased detection of abdominal aortic aneurysms. Thus the utility is low in terms of detection of malignancy. Based on this study we do not recommend routine computed tomography post heart transplantation. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Near-infrared dye marking for thoracoscopic resection of small-sized pulmonary nodules: comparison of percutaneous and bronchoscopic injection techniques.

PubMed

Anayama, Takashi; Hirohashi, Kentaro; Miyazaki, Ryohei; Okada, Hironobu; Kawamoto, Nobutaka; Yamamoto, Marino; Sato, Takayuki; Orihashi, Kazumasa

2018-01-12

Minimally invasive video-assisted thoracoscopic surgery for small-sized pulmonary nodules is challenging, and image-guided preoperative localisation is required. Near-infrared indocyanine green fluorescence is capable of deep tissue penetration and can be distinguished regardless of the background colour of the lung; thus, indocyanine green has great potential for use as a near-infrared fluorescent marker in video-assisted thoracoscopic surgery. Thirty-seven patients with small-sized pulmonary nodules, who were scheduled to undergo video-assisted thoracoscopic wedge resection, were enrolled in this study. A mixture of diluted indocyanine green and iopamidol was injected into the lung parenchyma as a marker, using either computed tomography-guided percutaneous or bronchoscopic injection techniques. Indications and limitations of the percutaneous and bronchoscopic injection techniques for marking nodules with indocyanine green fluorescence were examined and compared. In the computed tomography-guided percutaneous injection group (n = 15), indocyanine green fluorescence was detected in 15/15 (100%) patients by near-infrared thoracoscopy. A small pneumothorax occurred in 3/15 (20.0%) patients, and subsequent marking was unsuccessful after a pneumothorax occurred. In the bronchoscopic injection group (n = 22), indocyanine green fluorescence was detected in 21/22 (95.5%) patients. In 6 patients who underwent injection marking at 2 different lesion sites, 5/6 (83.3%) markers were successfully detected. Either computed tomography-guided percutaneous or bronchoscopic injection techniques can be used to mark pulmonary nodules with indocyanine green fluorescence. Indocyanine green is a safe and easily detectable fluorescent marker for video-assisted thoracoscopic surgery. Furthermore, the bronchoscopic injection approach enables surgeons to mark multiple lesion areas with less risk of causing a pneumothorax. UMIN-CTR R000027833 accepted by ICMJE. Registered 5 January 2013.

Utilization of cardiac computed tomography angiography and outpatient invasive coronary angiography in Ontario, Canada.

PubMed

Roifman, Idan; Rezai, Mohammad R; Wijeysundera, Harindra C; Chow, Benjamin J W; Wright, Graham A; Tu, Jack V

2015-01-01

Cardiac computed tomography angiography (coronary CTA) has emerged as a non-invasive method of diagnosing coronary artery disease. The extent of utilization and uptake of this technology since initiation of its funding by the government of Ontario is unknown. The aim of our study was to examine coronary CTA utilization and the rates of elective invasive coronary angiography and revascularization before and after funding initiation. We studied all coronary CTAs performed on adults in Ontario after initiation of funding. We also used an interrupted time series analysis to compare the average monthly rates of invasive angiography and revascularization before and after initiation of funding. There was an initial steep increase in age-and sex-standardized rates of coronary CTA from 5.0 to 11.4/100,000 over the first two quarters after funding initiation. Afterwards, there was a gradual increase in utilization from 11.4 to 17.1/100,000 over two subsequent calendar years. There was a significant reduction in both the mean monthly outpatient invasive coronary angiography (from 20.7 to 19.9 per 100,000 (p = 0.0004)) and revascularization (from 4.9 to 4.4 per 100,000 (p < 0.0001)) rates in the three years following introduction of the coronary CTA billing code as compared to the three prior to its introduction. Since the introduction of coronary CTA funding in Ontario, there has been a steady and controlled increase in its utilization. The increasing use of coronary CTA was associated with a reduction in both the rates of invasive angiography and revascularization. Copyright © 2015 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

Computed tomography versus invasive coronary angiography: design and methods of the pragmatic randomised multicentre DISCHARGE trial.

PubMed

Napp, Adriane E; Haase, Robert; Laule, Michael; Schuetz, Georg M; Rief, Matthias; Dreger, Henryk; Feuchtner, Gudrun; Friedrich, Guy; Špaček, Miloslav; Suchánek, Vojtěch; Fuglsang Kofoed, Klaus; Engstroem, Thomas; Schroeder, Stephen; Drosch, Tanja; Gutberlet, Matthias; Woinke, Michael; Maurovich-Horvat, Pál; Merkely, Béla; Donnelly, Patrick; Ball, Peter; Dodd, Jonathan D; Quinn, Martin; Saba, Luca; Porcu, Maurizio; Francone, Marco; Mancone, Massimo; Erglis, Andrejs; Zvaigzne, Ligita; Jankauskas, Antanas; Sakalyte, Gintare; Harań, Tomasz; Ilnicka-Suckiel, Malgorzata; Bettencourt, Nuno; Gama-Ribeiro, Vasco; Condrea, Sebastian; Benedek, Imre; Čemerlić Adjić, Nada; Adjić, Oto; Rodriguez-Palomares, José; Garcia Del Blanco, Bruno; Roditi, Giles; Berry, Colin; Davis, Gershan; Thwaite, Erica; Knuuti, Juhani; Pietilä, Mikko; Kępka, Cezary; Kruk, Mariusz; Vidakovic, Radosav; Neskovic, Aleksandar N; Díez, Ignacio; Lecumberri, Iñigo; Geleijns, Jacob; Kubiak, Christine; Strenge-Hesse, Anke; Do, The-Hoang; Frömel, Felix; Gutiérrez-Ibarluzea, Iñaki; Benguria-Arrate, Gaizka; Keiding, Hans; Katzer, Christoph; Müller-Nordhorn, Jacqueline; Rieckmann, Nina; Walther, Mario; Schlattmann, Peter; Dewey, Marc

2017-07-01

More than 3.5 million invasive coronary angiographies (ICA) are performed in Europe annually. Approximately 2 million of these invasive procedures might be reduced by noninvasive tests because no coronary intervention is performed. Computed tomography (CT) is the most accurate noninvasive test for detection and exclusion of coronary artery disease (CAD). To investigate the comparative effectiveness of CT and ICA, we designed the European pragmatic multicentre DISCHARGE trial funded by the 7th Framework Programme of the European Union (EC-GA 603266). In this trial, patients with a low-to-intermediate pretest probability (10-60 %) of suspected CAD and a clinical indication for ICA because of stable chest pain will be randomised in a 1-to-1 ratio to CT or ICA. CT and ICA findings guide subsequent management decisions by the local heart teams according to current evidence and European guidelines. Major adverse cardiovascular events (MACE) defined as cardiovascular death, myocardial infarction and stroke as a composite endpoint will be the primary outcome measure. Secondary and other outcomes include cost-effectiveness, radiation exposure, health-related quality of life (HRQoL), socioeconomic status, lifestyle, adverse events related to CT/ICA, and gender differences. The DISCHARGE trial will assess the comparative effectiveness of CT and ICA. • Coronary artery disease (CAD) is a major cause of morbidity and mortality. • Invasive coronary angiography (ICA) is the reference standard for detection of CAD. • Noninvasive computed tomography angiography excludes CAD with high sensitivity. • CT may effectively reduce the approximately 2 million negative ICAs in Europe. • DISCHARGE addresses this hypothesis in patients with low-to-intermediate pretest probability for CAD.

Cardiac computed tomography in patients with symptomatic new-onset atrial fibrillation, rule-out acute coronary syndrome, but with intermediate pretest probability for coronary artery disease admitted to a chest pain unit.

PubMed

Koopmann, Matthias; Hinrichs, Liane; Olligs, Jan; Lichtenberg, Michael; Eckardt, Lars; Böse, Dirk; Möhlenkamp, Stefan; Waltenberger, Johannes; Breuckmann, Frank

2018-01-24

Atrial fibrillation (AF) and coronary artery disease (CAD) may be encountered coincidently in a large portion of patients. However, data on coronary artery calcium burden in such patients are lacking. Thus, we sought to determine the value of cardiac computed tomography (CCT) in patients presenting with new-onset AF associated with an intermediate pretest probability for CAD admitted to a chest pain unit (CPU). Calcium scores (CS) of 73 new-onset, symptomatic AF subjects without typical clinical, electrocardiographic, or laboratory signs of acute coronary syndrome (ACS) admitted to our CPU were analyzed. In addition, results from computed tomography angiography (CTA) were related to coronary angiography findings whenever available. Calcium scores of zero were found in 25%. Median Agatston score was 77 (interquartile range: 1-270) with gender- and territory-specific dispersal. CS scores above average were present in about 50%, high (> 400)-to-very high (> 1000) CS scores were found in 22%. Overall percentile ranking showed a relative accordance to the reference percentile distribution. Additional CTA was performed in 47%, revealing stenoses in 12%. Coronary angiography was performed in 22% and resulted in coronary intervention or surgical revascularization in 7%. On univariate analysis, CS > 50th percentile failed to serve as an independent determinant of significant stenosis during catheterization. Within a CPU setting, relevant CAD was excluded or confirmed in almost 50%, the latter with a high proportion of coronary angiographies and subsequent coronary interventions, underlining the diagnostic value of CCT in symptomatic, non-ACS, new-onset AF patients when admitted to a CPU.

Usefulness of computed tomography in pre-surgical evaluation of maxillo-facial pathology with rapid prototyping and surgical pre-planning by virtual reality.

PubMed

Toso, Francesco; Zuiani, Chiara; Vergendo, Maurizio; Salvo, Iolanda; Robiony, Massimo; Politi, Massimo; Bazzocchi, Massimo

2005-01-01

To validate a protocol for creating virtual models to be used in the construction of solid prototypes useful for the planning-simulation of maxillo-facial surgery, in particular for very complex anatomic and pathologic problems. To optimize communications between the radiology, engineering and surgical laboratories. We studied 16 patients with different clinical problems of the maxillo-facial district. Exams were performed with multidetector computed tomography (MDCT) and single slice computed tomography (SDCT) with axial scans and collimation of 0.5-2 mm, and reconstruction interval of 1 mm. Subsequently we performed 2D multiplanar reconstructions and 3D volume-rendering reconstructions. We exported the DICOM images to the engineering laboratory, to recognize and isolate the bony structures by software. With these data the solid prototypes were generated using stereolitography. To date, surgery has been preformed on 12 patients after simulation of the procedure on the stereolithographyc model. The solid prototypes constructed in the difficult cases were sufficiently detailed despite problems related to the artefacts generated by dental fillings an d prostheses. In the remaining cases the MPR/3D images were sufficiently detailed for surgical planning. The surgical results were excellent in all patients who underwent surgery, and the surgeons were satisfied with the improvement in quality and the reduction in time required for the procedure. MDCT enables rapid prototyping using solid replication, which was very helpful in maxillo-facial surgery, despite problems related to artifacts due to dental fillings and prosthesis within the acquisition field; solutions for this problem are work in progress. The protocol used for communication between the different laboratories was valid and reproducible.

Evaluation of the Diagnostic Accuracy of Conventional 2-Dimensional and 3-Dimensional Computed Tomography for Assessing Canine Sacral and Pelvic Fractures by Radiologists, Orthopedic Surgeons, and Veterinary Medical Students.

PubMed

Stieger-Vanegas, Susanne M; Senthirajah, Sri Kumar Jamie; Nemanic, Sarah; Baltzer, Wendy; Warnock, Jennifer; Hollars, Katelyn; Lee, Scott S; Bobe, Gerd

2015-08-01

To determine, using 3 groups of evaluators of varying experience reading orthopedic CT studies, if 3-dimensional computed tomography (3D-CT) provides a more accurate and time efficient method for diagnosis of canine sacral and pelvic fractures, and displacements of the sacroiliac and coxofemoral joints compared with 2-dimensional computed tomography (2D-CT). Retrospective clinical and prospective study. Dogs (n = 23): 12 dogs with traumatic pelvic fractures, 11 canine cadavers with pelvic trauma induced by a lateral impactor. All dogs had a 2D-CT exam of the pelvis and subsequent 3D-CT reconstructions from the 2D-CT images. Both 2D-CT and 3D-CT studies were anonymized and randomly presented to 2 veterinary radiologists, 2 veterinary orthopedic surgeons, and 2 veterinary medical students. Evaluators classified fractures using a confidence scale and recorded the duration of evaluation for each modality and case. 3D-CT was a more time-efficient technique for evaluation of traumatic sacral and pelvic injuries compared with 2D-CT in all evaluator groups irrespective of experience level reading orthopedic CT studies. However, for radiologists and surgeons, 2D-CT was the more accurate technique for evaluating sacral and pelvic fractures. 3D-CT improves sacral and pelvic fracture diagnosis when added to 2D-CT; however, 3D-CT has a reduced accuracy for evaluation of sacral and pelvic fractures if used without concurrent evaluation of 2D-CT images. © Copyright 2014 by The American College of Veterinary Surgeons.

Petamenophis (Padiamenemipet), an Egyptian Child Mummy Protected for Eternity: Revelation by Multidetector Computed Tomography.

PubMed

Martina, Maria Cristina; Cesarani, Federico; Boano, Rosa; Fiore Marochetti, Elisa; Gandini, Giovanni

The objective of our work was to report the most recent findings obtained with multidetector computed tomography of a child mummy from the Roman period (119-123 CE) housed at the Egyptian Museum in Turin, Italy. Multidetector computed tomography and postprocessing were applied to understand the embalming techniques, the nature of a foreign object, and anthropometrical values. The information was compared with that from other mummies that were buried in the same tomb, but today housed in different museums. New information regarding the embalming technique was revealed. Multidetector computed tomography allowed the identification of a knife-like metallic object, probably an amulet for the child's protection in the afterlife. Multidetector computed tomography and image postprocessing confirm their valuable role in noninvasive studies in ancient mummies and provided evidence of a unique cultural practice in the late history of Ancient Egypt such as placing a knife possibly as an amulet.

Diagnosis of sinusoidal obstruction syndrome by positron emission tomography/computed tomography: report of two cases treated by defibrotide.

PubMed

Gauthé, Mathieu; Bozec, Laurence; Bedossa, Pierre

2014-11-01

Sinusoidal obstruction syndrome (SOS) is a potentially fatal liver injury that mainly occurs after myeloablative chemotherapy. We report two cases of SOS investigated by 18F-fluorodeoxyglucose positron emission tomography/computed tomography and treated with defibrotide. © 2014 by the American Association for the Study of Liver Diseases.

Measuring Weld Profiles By Computer Tomography

NASA Technical Reports Server (NTRS)

Pascua, Antonio G.; Roy, Jagatjit

1990-01-01

Noncontacting, nondestructive computer tomography system determines internal and external contours of welded objects. System makes it unnecessary to take metallurgical sections (destructive technique) or to take silicone impressions of hidden surfaces (technique that contaminates) to inspect them. Measurements of contours via tomography performed 10 times as fast as measurements via impression molds, and tomography does not contaminate inspected parts.

Parallel Computing for the Computed-Tomography Imaging Spectrometer

NASA Technical Reports Server (NTRS)

Lee, Seungwon

2008-01-01

This software computes the tomographic reconstruction of spatial-spectral data from raw detector images of the Computed-Tomography Imaging Spectrometer (CTIS), which enables transient-level, multi-spectral imaging by capturing spatial and spectral information in a single snapshot.

Prehistological evaluation of benign and malignant pigmented skin lesions with optical computed tomography

NASA Astrophysics Data System (ADS)

Kokolakis, Athanasios; Zacharakis, Giannis; Krasagakis, Konstantin; Lasithiotakis, Konstantinos; Favicchio, Rosy; Spiliopoulos, George; Giannikaki, Elpida; Ripoll, Jorge; Tosca, Androniki

2012-06-01

Discrimination of benign and malignant melanocytic lesions is a major issue in clinical dermatology. Assessment of the thickness of melanoma is critical for prognosis and treatment selection. We aimed to evaluate a novel optical computed tomography (optical-CT) system as a tool for three-dimensional (3-D) imaging of melanocytic lesions and its ability to discriminate benign from malignant melanocytic lesions while simultaneously determining the thickness of invasive melanoma. Seventeen melanocytic lesions, one hemangioma, and normal skin were assessed immediately after their excision by optical-CT and subsequently underwent histopathological examination. Tomographic reconstructions were performed with a back-propagation algorithm calculating a 3-D map of the total attenuation coefficient (AC). There was a statistically significant difference between melanomas, dysplastic nevi, and non-dysplastic nevi, as indicated by Kruskal-Wallis test. Median AC values were higher for melanomas compared with dysplastic and non-dysplastic nevi. No statistically significant difference was observed when thickness values obtained by optical-CT were compared with histological thickness using a Wilcoxon sighed rank test. Our results suggest that optical-CT can be important for the immediate prehistological evaluation of biopsies, assisting the physician for a rapid assessment of malignancy and of the thickness of a melanocytic lesion.

Volumetric quantification of bone-implant contact using micro-computed tomography analysis based on region-based segmentation

PubMed Central

Kang, Sung-Won; Lee, Woo-Jin; Choi, Soon-Chul; Lee, Sam-Sun; Heo, Min-Suk; Huh, Kyung-Hoe

2015-01-01

Purpose We have developed a new method of segmenting the areas of absorbable implants and bone using region-based segmentation of micro-computed tomography (micro-CT) images, which allowed us to quantify volumetric bone-implant contact (VBIC) and volumetric absorption (VA). Materials and Methods The simple threshold technique generally used in micro-CT analysis cannot be used to segment the areas of absorbable implants and bone. Instead, a region-based segmentation method, a region-labeling method, and subsequent morphological operations were successively applied to micro-CT images. The three-dimensional VBIC and VA of the absorbable implant were then calculated over the entire volume of the implant. Two-dimensional (2D) bone-implant contact (BIC) and bone area (BA) were also measured based on the conventional histomorphometric method. Results VA and VBIC increased significantly with as the healing period increased (p<0.05). VBIC values were significantly correlated with VA values (p<0.05) and with 2D BIC values (p<0.05). Conclusion It is possible to quantify VBIC and VA for absorbable implants using micro-CT analysis using a region-based segmentation method. PMID:25793178

Do Changes in the Production Process Affect the Outcome of Ceramic Liners: A 3-Year Follow-Up Study.

PubMed

Schmidt-Braekling, Tom; Renner, Lisa; Mintz, Douglas N; Waldstein, Wenzel; Endo, Yoshimi; Boettner, Friedrich

2017-04-01

In 2011, the current liner was withdrawn from the market because of the potential risk for liner fracture secondary to increased pressures used to assemble the metal locking ring. The present study provides a short-term follow-up of patients with this implant. We retrospectively evaluated 63 consecutive hips in 53 patients operated by a single surgeon using a recalled ceramic-on-ceramic bearing. There were 30 women and 23 men with an average age of 50.6 years (range 20.3-63.5 years). The mean follow-up was 36.8 months. Six hips in 6 patients were revised (9.5%) because of a liner-fracture during the follow-up period. All liner fractures were identified on computer tomography imaging. Nine patients had self-reported episodes of squeaking (14.3%). All 6 patients that underwent revision surgery for liner fracture described squeaking before revision. There were no revisions for other causes. Two of the revised patients had a subsequent dislocation (33%). The recalled ceramic liner lots have an increased liner fracture rate. Patients with mechanical symptoms or squeaking should undergo computer tomography to rule out liner facture. Copyright © 2016 Elsevier Inc. All rights reserved.

Computed tomography and patient risk: Facts, perceptions and uncertainties

PubMed Central

Power, Stephen P; Moloney, Fiachra; Twomey, Maria; James, Karl; O’Connor, Owen J; Maher, Michael M

2016-01-01

Since its introduction in the 1970s, computed tomography (CT) has revolutionized diagnostic decision-making. One of the major concerns associated with the widespread use of CT is the associated increased radiation exposure incurred by patients. The link between ionizing radiation and the subsequent development of neoplasia has been largely based on extrapolating data from studies of survivors of the atomic bombs dropped in Japan in 1945 and on assessments of the increased relative risk of neoplasia in those occupationally exposed to radiation within the nuclear industry. However, the association between exposure to low-dose radiation from diagnostic imaging examinations and oncogenesis remains unclear. With improved technology, significant advances have already been achieved with regards to radiation dose reduction. There are several dose optimization strategies available that may be readily employed including omitting unnecessary images at the ends of acquired series, minimizing the number of phases acquired, and the use of automated exposure control as opposed to fixed tube current techniques. In addition, new image reconstruction techniques that reduce radiation dose have been developed in recent years with promising results. These techniques use iterative reconstruction algorithms to attain diagnostic quality images with reduced image noise at lower radiation doses. PMID:28070242

Imaging of cellular spread on a three-dimensional scaffold by means of a novel cell-labeling technique for high-resolution computed tomography.

PubMed

Thimm, Benjamin W; Hofmann, Sandra; Schneider, Philipp; Carretta, Roberto; Müller, Ralph

2012-03-01

Computed tomography (CT) represents a truly three-dimensional (3D) imaging technique that can provide high-resolution images on the cellular level. Thus, one approach to detect single cells is X-ray absorption-based CT, where cells are labeled with a dense, opaque material providing the required contrast for CT imaging. Within the present work, a novel cell-labeling method has been developed showing the feasibility of labeling fixed cells with iron oxide (FeO) particles for subsequent CT imaging and quantitative morphometry. A biotin-streptavidin detection system was exploited to bind FeO particles to its target endothelial cells. The binding of the particles was predominantly close to the cell centers on 2D surfaces as shown by light microscopy, scanning electron microscopy, and CT. When cells were cultured on porous, 3D polyurethane surfaces, significantly more FeO particles were detected compared with surfaces without cells and FeO particle labeling using CT. Here, we report on the implementation and evaluation of a novel cell detection method based on high-resolution CT. This system has potential in cell tracking for 3D in vitro imaging in the future.

Iterative reconstruction for x-ray computed tomography using prior-image induced nonlocal regularization.

PubMed

Zhang, Hua; Huang, Jing; Ma, Jianhua; Bian, Zhaoying; Feng, Qianjin; Lu, Hongbing; Liang, Zhengrong; Chen, Wufan

2014-09-01

Repeated X-ray computed tomography (CT) scans are often required in several specific applications such as perfusion imaging, image-guided biopsy needle, image-guided intervention, and radiotherapy with noticeable benefits. However, the associated cumulative radiation dose significantly increases as comparison with that used in the conventional CT scan, which has raised major concerns in patients. In this study, to realize radiation dose reduction by reducing the X-ray tube current and exposure time (mAs) in repeated CT scans, we propose a prior-image induced nonlocal (PINL) regularization for statistical iterative reconstruction via the penalized weighted least-squares (PWLS) criteria, which we refer to as "PWLS-PINL". Specifically, the PINL regularization utilizes the redundant information in the prior image and the weighted least-squares term considers a data-dependent variance estimation, aiming to improve current low-dose image quality. Subsequently, a modified iterative successive overrelaxation algorithm is adopted to optimize the associative objective function. Experimental results on both phantom and patient data show that the present PWLS-PINL method can achieve promising gains over the other existing methods in terms of the noise reduction, low-contrast object detection, and edge detail preservation.

Iterative Reconstruction for X-Ray Computed Tomography using Prior-Image Induced Nonlocal Regularization

PubMed Central

Ma, Jianhua; Bian, Zhaoying; Feng, Qianjin; Lu, Hongbing; Liang, Zhengrong; Chen, Wufan

2014-01-01

Repeated x-ray computed tomography (CT) scans are often required in several specific applications such as perfusion imaging, image-guided biopsy needle, image-guided intervention, and radiotherapy with noticeable benefits. However, the associated cumulative radiation dose significantly increases as comparison with that used in the conventional CT scan, which has raised major concerns in patients. In this study, to realize radiation dose reduction by reducing the x-ray tube current and exposure time (mAs) in repeated CT scans, we propose a prior-image induced nonlocal (PINL) regularization for statistical iterative reconstruction via the penalized weighted least-squares (PWLS) criteria, which we refer to as “PWLS-PINL”. Specifically, the PINL regularization utilizes the redundant information in the prior image and the weighted least-squares term considers a data-dependent variance estimation, aiming to improve current low-dose image quality. Subsequently, a modified iterative successive over-relaxation algorithm is adopted to optimize the associative objective function. Experimental results on both phantom and patient data show that the present PWLS-PINL method can achieve promising gains over the other existing methods in terms of the noise reduction, low-contrast object detection and edge detail preservation. PMID:24235272

Benefit from NASA

NASA Image and Video Library

2001-01-01

The high-tech art of digital signal processing (DSP) was pioneered at NASA's Jet Propulsion Laboratory (JPL) in the mid-1960s for use in the Apollo Lunar Landing Program. Designed to computer enhance pictures of the Moon, this technology became the basis for the Landsat Earth resources satellites and subsequently has been incorporated into a broad range of Earthbound medical and diagnostic tools. DSP is employed in advanced body imaging techniques including Computer-Aided Tomography, also known as CT and CATScan, and Magnetic Resonance Imaging (MRI). CT images are collected by irradiating a thin slice of the body with a fan-shaped x-ray beam from a number of directions around the body's perimeter. A tomographic (slice-like) picture is reconstructed from these multiple views by a computer. MRI employs a magnetic field and radio waves, rather than x-rays, to create images. In this photograph, a patient undergoes an open MRI.

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

PubMed

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

2009-01-01

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

A Projection Quality-Driven Tube Current Modulation Method in Cone-Beam CT for IGRT: Proof of Concept.

PubMed

Men, Kuo; Dai, Jianrong

2017-12-01

To develop a projection quality-driven tube current modulation method in cone-beam computed tomography for image-guided radiotherapy based on the prior attenuation information obtained by the planning computed tomography and then evaluate its effect on a reduction in the imaging dose. The QCKV-1 phantom with different thicknesses (0-400 mm) of solid water upon it was used to simulate different attenuation (μ). Projections were acquired with a series of tube current-exposure time product (mAs) settings, and a 2-dimensional contrast to noise ratio was analyzed for each projection to create a lookup table of mAs versus 2-dimensional contrast to noise ratio, μ. Before a patient underwent computed tomography, the maximum attenuation [Formula: see text] within the 95% range of each projection angle (θ) was estimated according to the planning computed tomography images. Then, a desired 2-dimensional contrast to noise ratio value was selected, and the mAs setting at θ was calculated with the lookup table of mAs versus 2-dimensional contrast to noise ratio,[Formula: see text]. Three-dimensional cone-beam computed tomography images were reconstructed using the projections acquired with the selected mAs. The imaging dose was evaluated with a polymethyl methacrylate dosimetry phantom in terms of volume computed tomography dose index. Image quality was analyzed using a Catphan 503 phantom with an oval body annulus and a pelvis phantom. For the Catphan 503 phantom, the cone-beam computed tomography image obtained by the projection quality-driven tube current modulation method had a similar quality to that of conventional cone-beam computed tomography . However, the proposed method could reduce the imaging dose by 16% to 33% to achieve an equivalent contrast to noise ratio value. For the pelvis phantom, the structural similarity index was 0.992 with a dose reduction of 39.7% for the projection quality-driven tube current modulation method. The proposed method could reduce the additional dose to the patient while not degrading the image quality for cone-beam computed tomography. The projection quality-driven tube current modulation method could be especially beneficial to patients who undergo cone-beam computed tomography frequently during a treatment course.

Real-time three-dimensional optical coherence tomography image-guided core-needle biopsy system.

PubMed

Kuo, Wei-Cheng; Kim, Jongsik; Shemonski, Nathan D; Chaney, Eric J; Spillman, Darold R; Boppart, Stephen A

2012-06-01

Advances in optical imaging modalities, such as optical coherence tomography (OCT), enable us to observe tissue microstructure at high resolution and in real time. Currently, core-needle biopsies are guided by external imaging modalities such as ultrasound imaging and x-ray computed tomography (CT) for breast and lung masses, respectively. These image-guided procedures are frequently limited by spatial resolution when using ultrasound imaging, or by temporal resolution (rapid real-time feedback capabilities) when using x-ray CT. One feasible approach is to perform OCT within small gauge needles to optically image tissue microstructure. However, to date, no system or core-needle device has been developed that incorporates both three-dimensional OCT imaging and tissue biopsy within the same needle for true OCT-guided core-needle biopsy. We have developed and demonstrate an integrated core-needle biopsy system that utilizes catheter-based 3-D OCT for real-time image-guidance for target tissue localization, imaging of tissue immediately prior to physical biopsy, and subsequent OCT imaging of the biopsied specimen for immediate assessment at the point-of-care. OCT images of biopsied ex vivo tumor specimens acquired during core-needle placement are correlated with corresponding histology, and computational visualization of arbitrary planes within the 3-D OCT volumes enables feedback on specimen tissue type and biopsy quality. These results demonstrate the potential for using real-time 3-D OCT for needle biopsy guidance by imaging within the needle and tissue during biopsy procedures.

Just Scan It!-Weapon Reconstruction in Computed Tomography on Historical and Current Swiss Military Guns.

PubMed

Franckenberg, Sabine; Binder, Thomas; Bolliger, Stephan; Thali, Michael J; Ross, Steffen G

2016-09-01

Cross-sectional imaging, such as computed tomography, has been increasingly implemented in both historic and recent postmortem forensic investigations. It aids in determining cause and manner of death as well as in correlating injuries to possible weapons. This study illuminates the feasibility of reconstructing guns in computed tomography and gives a distinct overview of historic and recent Swiss Army guns.

The use of computed tomography to diagnose chronic shoulder arthritis in an American white pelican (Pelecanus erythrorhynchos).

PubMed

Whitehead, Michelle C; Parker, Dennilyn L

2015-03-01

An American white pelican was presented with a complete left wing droop and no abnormal findings on conventional radiography. Computed tomography was used to diagnose chronic shoulder arthritis as a sequela to a suspected traumatic compressive fracture. This is the first case report to describe use of computed tomography to evaluate the avian shoulder joint.

Embracing Statistical Challenges in the Information Technology Age

DTIC Science & Technology

2006-01-01

computation and feature selection. Moreover, two research projects on network tomography and arctic cloud detection are used throughout the paper to bring...prominent Network Tomography problem, origin- destination (OD) traffic estimation. It demonstrates well how the two modes of data collection interact...software debugging (Biblit et al, 2005 [2]), and network tomography for computer network management. Computer sys- tem problems exist long before the IT

Computed Tomography For Internal Inspection Of Castings

NASA Technical Reports Server (NTRS)

Hanna, Timothy L.

1995-01-01

Computed tomography used to detect internal flaws in metal castings before machining and otherwise processing them into finished parts. Saves time and money otherwise wasted on machining and other processing of castings eventually rejected because of internal defects. Knowledge of internal defects gained by use of computed tomography also provides guidance for changes in foundry techniques, procedures, and equipment to minimize defects and reduce costs.

The Impact of Computed Tomography on Decision Making in Tibial Plateau Fractures.

PubMed

Castiglia, Marcello Teixeira; Nogueira-Barbosa, Marcello Henrique; Messias, Andre Marcio Vieira; Salim, Rodrigo; Fogagnolo, Fabricio; Schatzker, Joseph; Kfuri, Mauricio

2018-02-14

Schatzker introduced one of the most used classification systems for tibial plateau fractures, based on plain radiographs. Computed tomography brought to attention the importance of coronal plane-oriented fractures. The goal of our study was to determine if the addition of computed tomography would affect the decision making of surgeons who usually use the Schatzker classification to assess tibial plateau fractures. Image studies of 70 patients who sustained tibial plateau fractures were uploaded to a dedicated homepage. Every patient was linked to a folder which contained two radiographic projections (anteroposterior and lateral), three interactive videos of computed tomography (axial, sagittal, and coronal), and eight pictures depicting tridimensional reconstructions of the tibial plateau. Ten attending orthopaedic surgeons, who were blinded to the cases, were granted access to the homepage and assessed each set of images in two different rounds, separated to each other by an interval of 2 weeks. Each case was evaluated in three steps, where surgeons had access, respectively to radiographs, two-dimensional videos of computed tomography, and three-dimensional reconstruction images. After every step, surgeons were asked to present how would they classify the case using the Schatzker system and which surgical approaches would be appropriate. We evaluated the inter- and intraobserver reliability of the Schatzker classification using the Kappa concordance coefficient, as well as the impact of computed tomography in the decision making regarding the surgical approach for each case, by using the chi-square test and likelihood ratio. The interobserver concordance kappa coefficients after each assessment step were, respectively, 0.58, 0.62, and 0.64. For the intraobserver analysis, the coefficients were, respectively, 0.76, 0.75, and 0.78. Computed tomography changed the surgical approach selection for the types II, V, and VI of Schatzker ( p  < 0.01). The addition of computed tomography scans to plain radiographs improved the interobserver reliability of Schatzker classification. Computed tomography had a statistically significant impact in the selection of surgical approaches for the lateral tibial plateau. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Characterization of Phase Chemistry and Partitioning in a Family of High-Strength Nickel-Based Superalloys

NASA Astrophysics Data System (ADS)

Lapington, M. T.; Crudden, D. J.; Reed, R. C.; Moody, M. P.; Bagot, P. A. J.

2018-06-01

A family of novel polycrystalline Ni-based superalloys with varying Ti:Nb ratios has been created using computational alloy design techniques, and subsequently characterized using atom probe tomography and electron microscopy. Phase chemistry, elemental partitioning, and γ' character have been analyzed and compared with thermodynamic predictions created using Thermo-Calc. Phase compositions and γ' volume fraction were found to compare favorably with the thermodynamically predicted values, while predicted partitioning behavior for Ti, Nb, Cr, and Co tended to overestimate γ' preference over the γ matrix, often with opposing trends vs Nb concentration.

Endometriosis of the lung: report of a case and literature review

PubMed Central

2013-01-01

This paper reports a case of endometriosis of the lung in a 29-year-old woman with long-term periodic catamenial hemoptysis. A chest computed tomography image obtained during menstruation revealed a radiographic opaque lesion in the lingular segment of the left superior lobe. During bronchoscopy, bleeding in the mucosa of the distal bronchus of the lingular segment of the left superior lobe was observed. Histopathology subsequent to an exploratory thoracotomy confirmed the diagnosis of endometriosis of the left lung. The 2-year follow-up after lingular lobectomy of the left superior lobe showed no recurrence or complications. PMID:23634803

Papillary carcinoma in ectopic thyroid detected by Tl-201 scintigraphy

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

Michigishi, T.; Mizukami, Y.; Mura, T.

1991-05-01

A 37-year-old man with papillary carcinoma in an ectopic thyroid is presented. Excisional biopsy revealed the cervical mass to be a metastasis from thyroid cancer. X-ray, ultrasonography, and computed tomography, however, failed to identify the primary tumor in the thyroid. Incidental TI-201 uptake was noted in the midline of the anterior neck, and a palpable nodule was discovered in this area. Fine needle aspiration cytology demonstrated Class V papillary adenocarcinoma, and subsequent surgery confirmed a papillary carcinoma in the ectopic thyroid. This case suggests the usefulness of TI-201 scintigraphy for the detection of ectopic thyroid malignancy.

Severe tracheal stenosis with tracheopathia osteoplastica-like changes due to traumatic blunt injury.

PubMed

Kakinuma, Kazutaka; Morikawa, Kei; Miyamoto, Yasuhiro; Saji, Hisashi; Mineshita, Masamichi; Miyazawa, Teruomi

2014-12-01

A 17-year-old man was injured in a motorcycle accident, leading to a complex cerebral contusion and hepatic injury. Approximately one month after being discharged from the hospital, the patient experienced gradually progressive dyspnea on exertion. Chest computed tomography revealed severe upper tracheal stenosis; thus, emergency tracheotomy and subsequent tracheoplasty were performed. Microscopically, the deformation of tracheal cartilage and extensive interstitial ossification/fibro-elastic changes were observed. To our knowledge, this is the first report documenting the ossification of the trachea that rapidly progressed after injury, which was confirmed by surgical resection of the upper trachea.

Diagnostic Approach to Pediatric Spine Disorders.

PubMed

Rossi, Andrea; Martinetti, Carola; Morana, Giovanni; Severino, Mariasavina; Tortora, Domenico

2016-08-01

Understanding the developmental features of the pediatric spine and spinal cord, including embryologic steps and subsequent growth of the osteocartilaginous spine and contents is necessary for interpretation of the pathologic events that may affect the pediatric spine. MR imaging plays a crucial role in the diagnostic evaluation of patients suspected of harboring spinal abnormalities, whereas computed tomography and ultrasonography play a more limited, complementary role. This article discusses the embryologic and developmental anatomy features of the spine and spinal cord, together with some technical points and pitfalls, and the most common indications for pediatric spinal MR imaging. Copyright © 2016 Elsevier Inc. All rights reserved.

A broken heart: right ventricular rupture after blunt cardiac injury.

PubMed

Nabeel, Muhammad; Williams, Kim Allan

2013-01-01

A 68 year old woman who was a restrained driver was brought to the hospital after sustaining severe motor vehicle accident. She underwent CT of the chest demonstrating pulmonary infiltrates, multiple rib fractures, bilateral hemo- and pneumothoraces. Subsequent review of the images noted contrast extravasating from the apical portion of the right ventricle into the pericardial space, demonstrating a confined rupture of right ventricle. Cardiac rupture is a common complication of a rare event and there are few examples in the imaging literature capturing such event. Copyright © 2013 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

Acute pericarditis with cardiac tamponade induced by pacemaker implantation.

PubMed

Shingaki, Masami; Kobayashi, Yutaka; Suzuki, Haruo

2015-11-01

An 87-year-old woman was diagnosed with third-degree atrioventricular block and underwent pacemaker implantation. On postoperative day 12, she experienced cardiac tamponade that was suspected on computed tomography to be caused by lead perforation; therefore, we performed open-heart surgery. However, we could not identify a perforation site on the heart, and drained a 400-mL exudative pericardial effusion. Subsequently, we diagnosed the pericardial effusion as due to pericarditis induced by pacemaker implantation. It is sometimes difficult to distinguish pericarditis from pacemaker lead perforation, so both should be included in the differential diagnosis. © The Author(s) 2014.

L1 Epithelioid Hemangioma.

PubMed

Davis, Joel D; Koppenhaver, Shane

2017-05-01

A 24-year-old male soldier on limited-duty status was referred to physical therapy by his primary care physician for a 2-year history of insidious-onset and slowly progressive low back pain. Lumbar radiographs were noncontributory. Shortly after initiating rehabilitation, the patient underwent magnetic resonance imaging that was previously ordered by his primary care physician. Radiology identified a complex mass and cortical fracturing within the L1 vertebral body, and subsequent computed tomography imaging demonstrated mixed sclerotic and lytic foci at L1. Biopsy later confirmed an epithelioid hemangioma. J Orthop Sports Phys Ther 2017;47(5):367. doi:10.2519/jospt.2017.6689.

Use of n-butyl cyanoacrylate to reduce left to right shunting of an abdominal arteriovenous malformation in a dog.

PubMed

Eason, B D; Hogan, D F; Lim, C; Hogan, M J

2017-08-01

A 9-month old castrated male Labradoodle presented to the cardiology service at Purdue University for evaluation of a low-grade murmur. Physical examination, thoracic radiography, and echocardiography were strongly supportive of an extracardiac left-to-right shunt. Subsequent evaluation with nuclear scintigraphy and computed tomography angiography revealed a large, complex arteriovenous malformation within the cranial abdomen. Staged interventional attenuation of the shunt was performed using n-butyl cyanoacrylate that resulted in a reduction in echocardiographic and nuclear scintigraphy derived shunt estimation. Copyright © 2017 Elsevier B.V. All rights reserved.

Sarcoid-resembling granulomatous lung disease secondary to occupational magnetite iron dust exposure.

PubMed

Xiao, Lewis; Kookana, Anil; McClure, Robert; Heraganahally, Subash

2018-08-01

Non-caseating granulomatous pulmonary conditions resembling sarcoidosis secondary to industrial/occupation exposure to magnetite iron ore dusts have been rarely documented in the literature. This is a case report of a 58-year-old blast crew member involved in iron ore/magnetite mining who presented with a 12-month history of chronic dry cough. High-resolution computed tomography revealed bilateral interstitial opacities. Lung biopsy demonstrated sarcoid-like granulomatous inflammation. Oral corticosteroid treatment improved the cough. Radiological features did not resolve despite treatment and yet remained stable following no subsequent exposure to iron mining dust.

Postmortem whole-body computed tomography angiography visualizing vascular rupture in a case of fatal car crash.

PubMed

Flach, Patricia M; Ross, Steffen G; Bolliger, Stephan A; Preiss, Ulrich S; Thali, Michael J; Spendlove, Danny

2010-01-01

In addition to the increasingly significant role of multislice computed tomography in forensic pathology, the performance of whole-body computed tomography angiography provides outstanding results. In this case, we were able to detect multiple injuries of the parenchymal organs in the upper abdomen as well as lesions of the brain parenchyma and vasculature of the neck. The radiologic findings showed complete concordance with the autopsy and even supplemented the autopsy findings in areas that are difficult to access via a manual dissection (such as the vasculature of the neck). This case shows how minimally invasive computed tomography angiography can serve as an invaluable adjunct to the classic autopsy procedure.

Computed tomography in the evaluation of Crohn disease

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

Goldberg, H.I.; Gore, R.M.; Margulis, A.R.

1983-02-01

The abdominal and pelvic computed tomographic examinations in 28 patients with Crohn disease were analyzed and correlated with conventional barium studies, sinograms, and surgical findings. Mucosal abnormalities such as aphthous lesions, pseudopolyps, and ulcerations were only imaged by conventional techniques. Computed tomography proved superior in demonstrating the mural, serosal, and mesenteric abnormalities such as bowel wall thickening (82%), fibrofatty proliferation of mesenteric fat (39%), mesenteric abscess (25%), inflammatory reaction of the mesentery (14%), and mesenteric lymphadenopathy (18%). Computed tomography was most useful clinically in defining the nature of mass effects, separation, or displacement of small bowel segments seen on smallmore » bowel series. Although conventional barium studies remain the initial diagnostic procedure in evaluating Crohn disease, computed tomography can be a useful adjunct in resolving difficult clinical and radiologic diagnostic problems.« less

The efficacy of preoperative positron emission tomography-computed tomography (PET-CT) for detection of lymph node metastasis in cervical and endometrial cancer: clinical and pathological factors influencing it.

PubMed

Nogami, Yuya; Banno, Kouji; Irie, Haruko; Iida, Miho; Kisu, Iori; Masugi, Yohei; Tanaka, Kyoko; Tominaga, Eiichiro; Okuda, Shigeo; Murakami, Koji; Aoki, Daisuke

2015-01-01

We studied the diagnostic performance of (18)F-fluoro-2-deoxy-d-glucose-positron emission tomography/computed tomography in cervical and endometrial cancers with particular focus on lymph node metastases. Seventy patients with cervical cancer and 53 with endometrial cancer were imaged with (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography before lymphadenectomy. We evaluated the diagnostic performance of (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography using the final pathological diagnoses as the golden standard. We calculated the sensitivity, specificity, positive predictive value and negative predictive value of (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography. In cervical cancer, the results evaluated by cases were 33.3, 92.7, 55.6 and 83.6%, respectively. When evaluated by the area of lymph nodes, the results were 30.6, 98.9, 55.0 and 97.0%, respectively. As for endometrial cancer, the results evaluated by cases were 50.0, 93.9, 40.0 and 95.8%, and by area of lymph nodes, 45.0, 99.4, 64.3 and 98.5%, respectively. The limitation of the efficacy was found out by analyzing it by the region of the lymph node, the size of metastatic node, the historical type of tumor in cervical cancer and the prevalence of lymph node metastasis. The efficacy of positron emission tomography/computed tomography regarding the detection of lymph node metastasis in cervical and endometrial cancer is not established and has limitations associated with the region of the lymph node, the size of metastasis lesion in lymph node and the pathological type of primary tumor. The indication for the imaging and the interpretation of the results requires consideration for each case by the pretest probability based on the information obtained preoperatively. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Diagnostic ability of computed tomography using DentaScan software in endodontics: case reports.

PubMed

Siotia, Jaya; Gupta, Sunil K; Acharya, Shashi R; Saraswathi, Vidya

2011-01-01

Radiographic examination is essential in diagnosis and treatment planning in endodontics. Conventional radiographs depict structures in two dimensions only. The ability to assess the area of interest in three dimensions is advantageous. Computed tomography is an imaging technique which produces three-dimensional images of an object by taking a series of two-dimensional sectional X-ray images. DentaScan is a computed tomography software program that allows the mandible and maxilla to be imaged in three planes: axial, panoramic, and cross-sectional. As computed tomography is used in endodontics, DentaScan can play a wider role in endodontic diagnosis. It provides valuable information in the assessment of the morphology of the root canal, diagnosis of root fractures, internal and external resorptions, pre-operative assessment of anatomic structures etc. The aim of this article is to explore the clinical usefulness of computed tomography and DentaScan in endodontic diagnosis, through a series of four cases of different endodontic problems.

Recent Scientific Evidence and Technical Developments in Cardiovascular Computed Tomography.

PubMed

Marcus, Roy; Ruff, Christer; Burgstahler, Christof; Notohamiprodjo, Mike; Nikolaou, Konstantin; Geisler, Tobias; Schroeder, Stephen; Bamberg, Fabian

2016-05-01

In recent years, coronary computed tomography angiography has become an increasingly safe and noninvasive modality for the evaluation of the anatomical structure of the coronary artery tree with diagnostic benefits especially in patients with a low-to-intermediate pretest probability of disease. Currently, increasing evidence from large randomized diagnostic trials is accumulating on the diagnostic impact of computed tomography angiography for the management of patients with acute and stable chest pain syndrome. At the same time, technical advances have substantially reduced adverse effects and limiting factors, such as radiation exposure, the amount of iodinated contrast agent, and scanning time, rendering the technique appropriate for broader clinical applications. In this work, we review the latest developments in computed tomography technology and describe the scientific evidence on the use of cardiac computed tomography angiography to evaluate patients with acute and stable chest pain syndrome. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Dental application of novel finite element analysis software for three-dimensional finite element modeling of a dentulous mandible from its computed tomography images.

PubMed

Nakamura, Keiko; Tajima, Kiyoshi; Chen, Ker-Kong; Nagamatsu, Yuki; Kakigawa, Hiroshi; Masumi, Shin-ich

2013-12-01

This study focused on the application of novel finite-element analysis software for constructing a finite-element model from the computed tomography data of a human dentulous mandible. The finite-element model is necessary for evaluating the mechanical response of the alveolar part of the mandible, resulting from occlusal force applied to the teeth during biting. Commercially available patient-specific general computed tomography-based finite-element analysis software was solely applied to the finite-element analysis for the extraction of computed tomography data. The mandibular bone with teeth was extracted from the original images. Both the enamel and the dentin were extracted after image processing, and the periodontal ligament was created from the segmented dentin. The constructed finite-element model was reasonably accurate using a total of 234,644 nodes and 1,268,784 tetrahedral and 40,665 shell elements. The elastic moduli of the heterogeneous mandibular bone were determined from the bone density data of the computed tomography images. The results suggested that the software applied in this study is both useful and powerful for creating a more accurate three-dimensional finite-element model of a dentulous mandible from the computed tomography data without the need for any other software.

Rib Radiography versus Chest Computed Tomography in the Diagnosis of Rib Fractures.

PubMed

Sano, Atsushi

2018-05-01

 The accurate diagnosis of rib fractures is important in chest trauma. Diagnostic images following chest trauma are usually obtained via chest X-ray, chest computed tomography, or rib radiography. This study evaluated the diagnostic characteristics of rib radiography and chest computed tomography.  Seventy-five rib fracture patients who underwent both chest computed tomography and rib radiography between April 2008 and December 2013 were included. Rib radiographs, centered on the site of pain, were taken from two directions. Chest computed tomography was performed using a 16-row multidetector scanner with 5-mm slice-pitch without overlap, and axial images were visualized in a bone window.  In total, 217 rib fractures were diagnosed in 75 patients. Rib radiography missed 43 rib fractures in 24 patients. The causes were overlap with organs in 15 cases, trivial fractures in 21 cases, and injury outside the imaging range in 7 cases. Left lower rib fractures were often missed due to overlap with the heart, while middle and lower rib fractures were frequently not diagnosed due to overlap with abdominal organs. Computed tomography missed 21 rib fractures in 17 patients. The causes were horizontal fractures in 10 cases, trivial fractures in 9 cases, and insufficient breath holding in 1 case.  In rib radiography, overlap with organs and fractures outside the imaging range were characteristic reasons for missed diagnoses. In chest computed tomography, horizontal rib fractures and insufficient breath holding were often responsible. We should take these challenges into account when diagnosing rib fractures. Georg Thieme Verlag KG Stuttgart · New York.

64 slice-coronary computed tomography sensitivity and specificity in the evaluation of coronary artery bypass graft stenosis: A meta-analysis.

PubMed

Barbero, Umberto; Iannaccone, Mario; d'Ascenzo, Fabrizio; Barbero, Cristina; Mohamed, Abdirashid; Annone, Umberto; Benedetto, Sara; Celentani, Dario; Gagliardi, Marco; Moretti, Claudio; Gaita, Fiorenzo

2016-08-01

A non-invasive approach to define grafts patency and stenosis in the follow-up of coronary artery bypass graft (CABG) patients may be an interesting alternative to coronary angiography. 64-slice-coronary computed tomography is nowadays a diffused non-invasive method that permits an accurate evaluation of coronary stenosis, due to a high temporal and spatial resolution. However, its sensitivity and specificity in CABG evaluation has to be clearly defined, since published studies used different protocols and scanners. We collected all studies investigating patients with stable symptoms and previous CABG and reporting the comparison between diagnostic performances of invasive coronary angiography and 64-slice-coronary computed tomography. As a result, sensitivity and specificity of 64-slice-coronary computed tomography for CABG occlusion were 0.99 (95% CI 0.97-1.00) and 0.99 (95% CI: 0.99-1.00) with an area under the curve (AUC) of 0.99. 64-slice-coronary computed tomography sensitivity and specificity for the presence of any CABG stenosis >50% were 0.98 (95% CI: 0.97-0.99) and 0.98 (95% CI: 0.96-0.98), while AUC was 0.99. At meta-regression, neither the age nor the time from graft implantation had effect on sensitivity and specificity of 64-slice-coronary computed tomography detection of significant CABG stenosis or occlusion. In conclusion 64-slice-coronary computed tomography confirmed its high sensitivity and specificity in CABG stenosis or occlusion evaluation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Quadruple Axis Neutron Computed Tomography

NASA Astrophysics Data System (ADS)

Schillinger, Burkhard; Bausenwein, Dominik

Neutron computed tomography takes more time for a full tomography than X-rays or Synchrotron radiation, because the source intensity is limited. Most neutron imaging detectors have a square field of view, so if tomography of elongated, narrow samples, e.g. fuel rods, sword blades is recorded, much of the detector area is wasted. Using multiple rotation axes, several samples can be placed inside the field of view, and multiple tomographies can be recorded at the same time by later splitting the recorded images into separate tomography data sets. We describe a new multiple-axis setup using four independent miniaturized rotation tables.

Minimal invasive localization of the germinal disc in ovo for subsequent chicken sexing using optical coherence tomography

NASA Astrophysics Data System (ADS)

Burkhardt, Anke; Geissler, Stefan; Cimalla, Peter; Walther, Julia; Koch, Edmund

2010-02-01

Reason for using optical coherence tomography (OCT) to locate the germinal disc is the questionable and ethically alarming killing of male layer chickens because for the layer line only the females are necessary. To avoid this and to protect the animal rights, the sex of the fertilized chicken egg has to be determined as early as possible in the unincubated state. Because the information whether the chick becomes male or female can be found in the germinal disc an accurate localization for sexing is essential. The germinal disc is located somewhere on top of the yolk and has a diameter of approximately 4 - 5 mm. Different imaging methods like ultrasonography, 3D-X-ray micro computed tomography and magnetic resonance imaging were used for localization until now, but found to be impractical. The goal of this study is to prove if OCT can be a moderate approach for the precise in ovo localization. Because the eggshell is an impenetrable barrier for OCT and to minimize the penetration of germs a very small hole is placed in the eggshell and a fan-shaped optical scanning pattern is used.

Impact of Single-Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) and Positron Emission Tomography/Computed Tomography (PET/CT) in the Diagnosis of Traumatic Brain Injury (TBI): Case Report.

PubMed

Molina-Vicenty, Irma L; Santiago-Sánchez, Michelaldemar; Vélez-Miró, Iván; Motta-Valencia, Keryl

2016-09-01

Traumatic brain injury (TBI) is defined as damage to the brain resulting from an external force. TBI, a global leading cause of death and disability, is associated with serious social, economic, and health problems. In cases of mild-to-moderate brain damage, conventional anatomical imaging modalities may or may not detect the cascade of metabolic changes that have occurred or are occurring at the intracellular level. Functional nuclear medicine imaging and neurophysiological parameters can be used to characterize brain damage, as the former provides direct visualization of brain function, even in the absence of overt behavioral manifestations or anatomical findings. We report the case of a 30-year-old Hispanic male veteran who, after 2 traumatic brain injury events, developed cognitive and neuropsychological problems with no clear etiology in the presence of negative computed tomography (CT) findings.

Advanced Computed-Tomography Inspection System

NASA Technical Reports Server (NTRS)

Harris, Lowell D.; Gupta, Nand K.; Smith, Charles R.; Bernardi, Richard T.; Moore, John F.; Hediger, Lisa

1993-01-01

Advanced Computed Tomography Inspection System (ACTIS) is computed-tomography x-ray apparatus revealing internal structures of objects in wide range of sizes and materials. Three x-ray sources and adjustable scan geometry gives system unprecedented versatility. Gantry contains translation and rotation mechanisms scanning x-ray beam through object inspected. Distance between source and detector towers varied to suit object. System used in such diverse applications as development of new materials, refinement of manufacturing processes, and inspection of components.

Usefulness of Tc99m-mebrofenin Hepatobiliary Scintigraphy and Single Photon Emission Computed Tomography/Computed Tomography in the Diagnosis of Bronchobiliary Fistula.

PubMed

Parghane, Rahul Vithalrao; Phulsunga, Rohit Kumar; Gupta, Rajesh; Basher, Rajender Kumar; Bhattacharya, Anish; Mittal, Bhagwant Rai

2017-01-01

Bronchobiliary fistula (BBF), a rare complication of liver disease, is an abnormal communication between the biliary tract and bronchial tree. BBF may occur as a consequence of local liver infections such as hydatid or amebic disease, pyogenic liver abscess or trauma to the liver, obstruction of biliary tract, and tumor. As such management of liver disease with BBF is very difficult and often associated with a high rate of morbidity and mortality. Therefore, timely diagnosis of BBF is imperative. Hepatobiliary scintigraphy along with hybrid single photon emission computed tomography/computed tomography using Tc99m-mebrofenin is a very useful noninvasive imaging modality, in the diagnosis of BBF.

Usefulness of Tc99m-mebrofenin Hepatobiliary Scintigraphy and Single Photon Emission Computed Tomography/Computed Tomography in the Diagnosis of Bronchobiliary Fistula

PubMed Central

Parghane, Rahul Vithalrao; Phulsunga, Rohit Kumar; Gupta, Rajesh; Basher, Rajender Kumar; Bhattacharya, Anish; Mittal, Bhagwant Rai

2017-01-01

Bronchobiliary fistula (BBF), a rare complication of liver disease, is an abnormal communication between the biliary tract and bronchial tree. BBF may occur as a consequence of local liver infections such as hydatid or amebic disease, pyogenic liver abscess or trauma to the liver, obstruction of biliary tract, and tumor. As such management of liver disease with BBF is very difficult and often associated with a high rate of morbidity and mortality. Therefore, timely diagnosis of BBF is imperative. Hepatobiliary scintigraphy along with hybrid single photon emission computed tomography/computed tomography using Tc99m-mebrofenin is a very useful noninvasive imaging modality, in the diagnosis of BBF. PMID:29033682

Weightbearing Computed Tomography of the Foot and Ankle: Emerging Technology Topical Review.

PubMed

Barg, Alexej; Bailey, Travis; Richter, Martinus; de Cesar Netto, Cesar; Lintz, François; Burssens, Arne; Phisitkul, Phinit; Hanrahan, Christopher J; Saltzman, Charles L

2018-03-01

In the last decade, cone-beam computed tomography technology with improved designs allowing flexible gantry movements has allowed both supine and standing weight-bearing imaging of the lower extremity. There is an increasing amount of literature describing the use of weightbearing computed tomography in patients with foot and ankle disorders. To date, there is no review article summarizing this imaging modality in the foot and ankle. Therefore, we performed a systematic literature review of relevant clinical studies targeting the use of weightbearing computed tomography in diagnosis of patients with foot and ankle disorders. Furthermore, this review aims to offer insight to those with interest in considering possible future research opportunities with use of this technology. Level V, expert opinion.

SPECT/CT localization of oral radioiodine activity: a retrospective study and in-vitro assessment

PubMed Central

Burlison, Jared S.; Hartshorne, Michael F.; Voda, Alan M.; Cocks, Franklin H.

2013-01-01

Purpose We sought to further localize radioiodine activity in the mouth on post-thyroid cancer therapy imaging using single-photon emission computed tomography/computed tomography (SPECT/CT). Materials and methods We retrospectively reviewed all patients (58) who underwent thyroid cancer therapy with iodine-131 (131I) at our institution from August 2009 to March 2011 whose post-therapy radioiodine imaging included neck SPECT/CT. A small group (six) of diagnostic 123I scans including SPECT/CT was also reviewed. Separately, we performed in-vitro 131I (sodium iodide) binding assays with amalgam and Argenco HP 77 (77% dental gold alloy) as proof of principle for these interactions. Results Of the 58 post-therapy patients, 45 (78%) had undergone metallic dental restorations, and of them 41 (91%) demonstrated oral 131I activity localizing preferentially to those restorations. It was observed that radioiodine also localized to other dental restorations and to orthodontic hardware. Gum-line activity in edentulous patients suggests radioiodine interaction with denture adhesive. In vitro, dental amalgam and Argenco HP 77 bound 131I in a time-dependent manner over 1–16 days of exposure. Despite subsequent washings with normal saline, significant 131I activity (maximally 12% for amalgam and 68% for Argenco HP 77) was retained by these metals. Subsequent soaking in a saturated solution of potassium iodide partially displaced 131I from amalgam, with near-total displacement of 131I from Argenco HP 77. Conclusion SPECT/CT shows that radioiodine in the oral cavity localizes to metallic dental restorations. Furthermore, in-vitro studies demonstrate partially reversible binding of 131I to common dental metals. PMID:24128897

Incidental findings in imaging research: evaluating incidence, benefit, and burden.

PubMed

Orme, Nicholas M; Fletcher, Joel G; Siddiki, Hassan A; Harmsen, W Scott; O'Byrne, Megan M; Port, John D; Tremaine, William J; Pitot, Henry C; McFarland, Elizabeth G; Robinson, Marguerite E; Koenig, Barbara A; King, Bernard F; Wolf, Susan M

2010-09-27

Little information exists concerning the frequency and medical significance of incidental findings (IFs) in imaging research. Medical records of research participants undergoing a research imaging examination interpreted by a radiologist during January through March 2004 were reviewed, with 3-year clinical follow-up. An expert panel reviewed all IFs generating clinical action to determine medical benefit/burden on the basis of predefined criteria. The frequency of IFs that generated further clinical action was estimated by modality, body part, age, and sex, along with net medical benefit or burden. Of 1426 research imaging examinations, 567 (39.8%) had at least 1 IF (1055 total). Risk of an IF increased significantly by age (odds ratio [OR], 1.5; 95% confidence interval, 1.4-1.7 per decade increase). Abdominopelvic computed tomography generated more IFs than other examinations (OR, 18.9 vs ultrasonography; 9.2% with subsequent clinical action), with computed tomography of the thorax and magnetic resonance imaging of the head next (OR, 11.9 and 5.9; 2.8% and 2.2% with action, respectively). Of the 567 examinations with an IF, 35 (6.2%) generated clinical action, resulting in clear medical benefit in 1.1% (6 of 567) and clear medical burden in 0.5% (3 of 567). Medical benefit/burden was usually unclear (26 of 567 [4.6%]). Frequency of IFs in imaging research examinations varies significantly by imaging modality, body region, and age. Research imaging studies at high risk for generating IFs can be identified. Routine evaluation of research images by radiologists may result in identification of IFs in a high number of cases and subsequent clinical action to address them in a small but significant minority. Such clinical action can result in medical benefit to a small number of patients.

Inconsistency in 9 mm bullets: correlation of jacket thickness to post-impact geometry measured with non-destructive X-ray computed tomography.

PubMed

Thornby, John; Landheer, Dirk; Williams, Tim; Barnes-Warden, Jane; Fenne, Paul; Norman, Danielle G; Attridge, Alex; Williams, Mark A

2014-01-01

Fundamental to any ballistic armour standard is the reference projectile to be defeated. Typically, for certification purposes, a consistent and symmetrical bullet geometry is assumed, however variations in bullet jacket dimensions can have far reaching consequences. Traditionally, characteristics and internal dimensions have been analysed by physically sectioning bullets--an approach which is of restricted scope and which precludes subsequent ballistic assessment. The use of a non-destructive X-ray computed tomography (CT) method has been demonstrated and validated (Kumar et al., 2011 [15]); the authors now apply this technique to correlate bullet impact response with jacket thickness variations. A set of 20 bullets (9 mm DM11) were selected for comparison and an image-based analysis method was employed to map jacket thickness and determine the centre of gravity of each specimen. Both intra- and inter-bullet variations were investigated, with thickness variations of the order of 200 μm commonly found along the length of all bullets and angular variations of up to 50 μm in some. The bullets were subsequently impacted against a rigid flat plate under controlled conditions (observed on a high-speed video camera) and the resulting deformed projectiles were re-analysed. The results of the experiments demonstrate a marked difference in ballistic performance between bullets from different manufacturers and an asymmetric thinning of the jacket is observed in regions of pre-impact weakness. The conclusions are relevant for future soft armour standards and provide important quantitative data for numerical model correlation and development. The implications of the findings of the work on the reliability and repeatability of the industry standard V50 ballistic test are also discussed. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Evaluating the risk of appendiceal perforation when using ultrasound as the initial diagnostic imaging modality in children with suspected appendicitis.

PubMed

Alerhand, Stephen; Meltzer, James; Tay, Ee Tein

2017-08-01

Ultrasound scan has gained attention for diagnosing appendicitis due to its avoidance of ionizing radiation. However, studies show that ultrasound scan carries inferior sensitivity to computed tomography scan. A non-diagnostic ultrasound scan could increase the time to diagnosis and appendicectomy, particularly if follow-up computed tomography scan is needed. Some studies suggest that delaying appendicectomy increases the risk of perforation. To investigate the risk of appendiceal perforation when using ultrasound scan as the initial diagnostic imaging modality in children with suspected appendicitis. We retrospectively reviewed 1411 charts of children ≤17 years old diagnosed with appendicitis at two urban academic medical centers. Patients who underwent ultrasound scan first were compared to those who underwent computed tomography scan first. In the sub-group analysis, patients who only received ultrasound scan were compared to those who received initial ultrasound scan followed by computed tomography scan. Main outcome measures were appendiceal perforation rate and time from triage to appendicectomy. In 720 children eligible for analysis, there was no significant difference in perforation rate between those who had initial ultrasound scan and those who had initial computed tomography scan (7.3% vs. 8.9%, p = 0.44), nor in those who had ultrasound scan only and those who had initial ultrasound scan followed by computed tomography scan (8.0% vs. 5.6%, p = 0.42). Those patients who had ultrasound scan first had a shorter triage-to-incision time than those who had computed tomography scan first (9.2 (IQR: 5.9, 14.0) vs. 10.2 (IQR: 7.3, 14.3) hours, p = 0.03), whereas those who had ultrasound scan followed by computed tomography scan took longer than those who had ultrasound scan only (7.8 (IQR: 5.3, 11.6) vs. 15.1 (IQR: 10.6, 20.6), p < 0.001). Children < 12 years old receiving ultrasound scan first had lower perforation rate (p = 0.01) and shorter triage-to-incision time (p = 0.003). Children with suspected appendicitis receiving ultrasound scan as the initial diagnostic imaging modality do not have increased risk of perforation compared to those receiving computed tomography scan first. We recommend that children <12 years of age receive ultrasound scan first.

Neural networks for calibration tomography

NASA Technical Reports Server (NTRS)

Decker, Arthur

1993-01-01

Artificial neural networks are suitable for performing pattern-to-pattern calibrations. These calibrations are potentially useful for facilities operations in aeronautics, the control of optical alignment, and the like. Computed tomography is compared with neural net calibration tomography for estimating density from its x-ray transform. X-ray transforms are measured, for example, in diffuse-illumination, holographic interferometry of fluids. Computed tomography and neural net calibration tomography are shown to have comparable performance for a 10 degree viewing cone and 29 interferograms within that cone. The system of tomography discussed is proposed as a relevant test of neural networks and other parallel processors intended for using flow visualization data.

Use of cone beam computed tomography in implant dentistry: current concepts, indications and limitations for clinical practice and research.

PubMed

Bornstein, Michael M; Horner, Keith; Jacobs, Reinhilde

2017-02-01

Diagnostic radiology is an essential component of treatment planning in the field of implant dentistry. This narrative review will present current concepts for the use of cone beam computed tomography imaging, before and after implant placement, in daily clinical practice and research. Guidelines for the selection of three-dimensional imaging will be discussed, and limitations will be highlighted. Current concepts of radiation dose optimization, including novel imaging modalities using low-dose protocols, will be presented. For preoperative cross-sectional imaging, data are still not available which demonstrate that cone beam computed tomography results in fewer intraoperative complications such as nerve damage or bleeding incidents, or that implants inserted using preoperative cone beam computed tomography data sets for planning purposes will exhibit higher survival or success rates. The use of cone beam computed tomography following the insertion of dental implants should be restricted to specific postoperative complications, such as damage of neurovascular structures or postoperative infections in relation to the maxillary sinus. Regarding peri-implantitis, the diagnosis and severity of the disease should be evaluated primarily based on clinical parameters and on radiological findings based on periapical radiographs (two dimensional). The use of cone beam computed tomography scans in clinical research might not yield any evident beneficial effect for the patient included. As many of the cone beam computed tomography scans performed for research have no direct therapeutic consequence, dose optimization measures should be implemented by using appropriate exposure parameters and by reducing the field of view to the actual region of interest. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

How reliably can computed tomography predict thyroid invasion prior to laryngectomy?

PubMed

Harris, Andrew S; Passant, Carl D; Ingrams, Duncan R

2018-05-01

There is little evidence to support the removal of thyroid tissue during total laryngectomy. Although oncological control of the tumor is the priority, thyroidectomy can lead to hypothyroidism and hypoparathyroidism. This study aimed to test the usefulness of preoperative computed tomography in predicting histological invasion of the thyroid. Ambispective cohort study. All patients undergoing total laryngectomy for squamous cell carcinoma at one center from 2006 to 2016 were included. Data were recorded prospectively as part of the patients' standard care, but were collated retrospectively, giving this study an ambispective design. The histology report for thyroid invasion was taken as the gold standard. The computed tomography report was categorized by invasion of tumor into intralaryngeal, laryngeal cartilage involvement, and extralaryngeal tissues. Seventy-nine patients were included. Nine patients had thyroid involvement on histology, translating to an incidence of 11.29% in this population. The positive predictive value for cartilage involvement on computed tomography for thyroid invasion was 52.9% (95% confidence interval [CI]: 28.5%-76.1%) and the negative predictive value was 100% (95% CI: 92.7%-100%).The positive predictive value for extralaryngeal spread on computed tomography for thyroid involvement was 100% (95% CI: 62.9%-100%), and the negative predictive value was also 100% (95% CI: 93.5%-100%). This study has shown that preoperative computed tomography is an effective method of ruling out thyroid gland invasion. The absence of extralaryngeal spread on computed tomography has been shown to be the most useful finding, with a high negative predictive value and a narrow 95% CI. 4. Laryngoscope, 128:1099-1102, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Integrating dimension reduction and out-of-sample extension in automated classification of ex vivo human patellar cartilage on phase contrast X-ray computed tomography.

PubMed

Nagarajan, Mahesh B; Coan, Paola; Huber, Markus B; Diemoz, Paul C; Wismüller, Axel

2015-01-01

Phase contrast X-ray computed tomography (PCI-CT) has been demonstrated as a novel imaging technique that can visualize human cartilage with high spatial resolution and soft tissue contrast. Different textural approaches have been previously investigated for characterizing chondrocyte organization on PCI-CT to enable classification of healthy and osteoarthritic cartilage. However, the large size of feature sets extracted in such studies motivates an investigation into algorithmic feature reduction for computing efficient feature representations without compromising their discriminatory power. For this purpose, geometrical feature sets derived from the scaling index method (SIM) were extracted from 1392 volumes of interest (VOI) annotated on PCI-CT images of ex vivo human patellar cartilage specimens. The extracted feature sets were subject to linear and non-linear dimension reduction techniques as well as feature selection based on evaluation of mutual information criteria. The reduced feature set was subsequently used in a machine learning task with support vector regression to classify VOIs as healthy or osteoarthritic; classification performance was evaluated using the area under the receiver-operating characteristic (ROC) curve (AUC). Our results show that the classification performance achieved by 9-D SIM-derived geometric feature sets (AUC: 0.96 ± 0.02) can be maintained with 2-D representations computed from both dimension reduction and feature selection (AUC values as high as 0.97 ± 0.02). Thus, such feature reduction techniques can offer a high degree of compaction to large feature sets extracted from PCI-CT images while maintaining their ability to characterize the underlying chondrocyte patterns.

Diverticular Disease of the Colon: News From Imaging.

PubMed

Flor, Nicola; Soldi, Simone; Zanchetta, Edoardo; Sbaraini, Sara; Pesapane, Filippo

2016-10-01

Different scenarios embrace computed tomography imaging and diverticula, including asymptomatic (diverticulosis) and symptomatic patients (acute diverticulitis, follow-up of acute diverticulitis, chronic diverticulitis). If the role of computed tomography is validated and widely supported by evidence in case of acute diverticulitis, this is not the case of patients in their follow-up for acute diverticulitis or with symptoms related to diverticula, but without acute inflammation. In these settings, computed tomography colonography is gaining consensus as the preferred radiologic test.

Plain X-ray, computed tomography and magnetic resonance imaging findings of telangiectatic osteosarcoma: a case report.

PubMed

Skiadas, Vasilios; Koutoulidis, Vasilios; Koureas, Andreas; Moulopoulos, Lia; Gouliamos, Athanasios

2009-09-16

An 18-year-old male patient presented with chronic nonspecific pain of three months located at his left proximal tibia. The patient was admitted to our department for plain X-ray, computed tomography and magnetic resonance imaging examination. Plain X-ray and computed tomography revealed a geographic lytic lesion at the medial aspect of the proximal tibia. Biopsy of the lesion showed telangiectatic osteosarcoma. Image findings of all modalities are presented.

Advances in equine computed tomography and use of contrast media.

PubMed

Puchalski, Sarah M

2012-12-01

Advances in equine computed tomography have been made as a result of improvements in software and hardware and an increasing body of knowledge. Contrast media can be administered intravascularly or intrathecally. Contrast media is useful to differentiate between tissues of similar density. Equine computed tomography can be used for many different clinical conditions, including lameness diagnosis, fracture identification and characterization, preoperative planning, and characterization of skull diseases. Copyright © 2012 Elsevier Inc. All rights reserved.

[The radiologist physician in major trauma evaluation].

PubMed

Motta-Ramírez, Gaspar Alberto

2016-01-01

Trauma is the most common cause of death in young adults. A multidisciplinary trauma team consists of at least a surgical team, an anesthesiology team, radiologic team, and an emergency department team. Recognize the integration of multidisciplinary medical team in managing the trauma patient and which must include the radiologist physician responsible for the institutional approach to the systematization of the trauma patient regarding any radiological and imaging study with emphasis on the FAST (del inglés, Focused Assessment with Sonography in Trauma)/USTA, Whole body computed tomography. Ultrasound is a cross-sectional method available for use in patients with major trauma. Whole-body multidetector computed tomography became the imaging modality of choice in the late 1990s. In patients with major trauma, examination FAST often is the initial imaging examination, extended to extraabdominal regions. Patients who have multitrauma from blunt mechanisms often require multiple diagnostic examinations, including Computed Tomography imaging of the torso as well as abdominopelvic Computed Tomography angiography. Multiphasic Whole-body trauma imaging is feasible, helps detect clinically relevant vascular injuries, and results in diagnostic image quality in the majority of patients. Computed Tomography has gained importance in the early diagnostic phase of trauma care in the emergency room. With a single continuous acquisition, whole-body computed tomography angiography is able to demonstrate all potentially injured organs, as well as vascular and bone structures, from the circle of Willis to the symphysis pubis.

Development of computational small animal models and their applications in preclinical imaging and therapy research.

PubMed

Xie, Tianwu; Zaidi, Habib

2016-01-01

The development of multimodality preclinical imaging techniques and the rapid growth of realistic computer simulation tools have promoted the construction and application of computational laboratory animal models in preclinical research. Since the early 1990s, over 120 realistic computational animal models have been reported in the literature and used as surrogates to characterize the anatomy of actual animals for the simulation of preclinical studies involving the use of bioluminescence tomography, fluorescence molecular tomography, positron emission tomography, single-photon emission computed tomography, microcomputed tomography, magnetic resonance imaging, and optical imaging. Other applications include electromagnetic field simulation, ionizing and nonionizing radiation dosimetry, and the development and evaluation of new methodologies for multimodality image coregistration, segmentation, and reconstruction of small animal images. This paper provides a comprehensive review of the history and fundamental technologies used for the development of computational small animal models with a particular focus on their application in preclinical imaging as well as nonionizing and ionizing radiation dosimetry calculations. An overview of the overall process involved in the design of these models, including the fundamental elements used for the construction of different types of computational models, the identification of original anatomical data, the simulation tools used for solving various computational problems, and the applications of computational animal models in preclinical research. The authors also analyze the characteristics of categories of computational models (stylized, voxel-based, and boundary representation) and discuss the technical challenges faced at the present time as well as research needs in the future.

High-resolution PET [Positron Emission Tomography] for Medical Science Studies

DOE R&D Accomplishments Database

Budinger, T. F.; Derenzo, S. E.; Huesman, R. H.; Jagust, W. J.; Valk, P. E.

1989-09-01

One of the unexpected fruits of basic physics research and the computer revolution is the noninvasive imaging power available to today's physician. Technologies that were strictly the province of research scientists only a decade or two ago now serve as the foundations for such standard diagnostic tools as x-ray computer tomography (CT), magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), ultrasound, single photon emission computed tomography (SPECT), and positron emission tomography (PET). Furthermore, prompted by the needs of both the practicing physician and the clinical researcher, efforts to improve these technologies continue. This booklet endeavors to describe the advantages of achieving high resolution in PET imaging.

Life-Saving Esophageal Intubation in Neonate With Undiagnosed Tracheal Agenesis: A Case Report.

PubMed

Sattler, Christopher; Chiao, Franklin; Stein, David; Murphy, Denise

2017-07-01

A 3-day-old, 2.2-kg former 34-week premature infant with imperforate anus required loop ileostomy surgery. At delivery, the child had respiratory distress. Endotracheal intubation was "confirmed" by detection of exhaled carbon dioxide with a Pedi-Cap (Covidien, Dublin, Ireland) and subsequent chest x-ray. On arrival to the operating room, the pulse oximeter reading was 100% despite a large leak around the endotracheal tube and high-airway pressures. Packing the throat reduced the leak and increased the tidal volume. Intraoperative bronchospasm occurred during the surgery. On postoperative day 1, fiberoptic examination by an otolaryngologist revealed esophageal intubation and the absence of laryngeal opening. Subsequent computed tomography scan revealed Floyd type II tracheal agenesis. To our knowledge, this is the only case of tracheal agenesis diagnosed after a non-airway related procedure. We discussed how the diagnosis was missed.

[A case of enterolith ileus secondary to acute pancreatitis associated with a juxtapapillary duodenal diverticulum].

PubMed

Morii, Shinji; Doi, Yoko; Makita, Tomoo; Takeda, Shinichiro; Miura, Seiki; Kaneko, Takaaki; Saito, Shuichi; Okabe, Shinichiro

2015-05-01

A 63-year-old woman with abdominal pain was referred to our hospital. Her pancreatic enzymes were elevated, and an abdominal computed tomography (CT) scan showed an enlarged pancreas, consistent with pancreatitis, and gas collection containing an impacted stone adjacent to Vater's papilla. This finding raised the suspicion of a duodenal diverticulum. A subsequent ERCP showed a juxtapapillary duodenal diverticulum (JPDD) filled with calculi and pus. The pancreatitis improved with 2 weeks of conservative treatment. Subsequently, the patient underwent resection of the uterus and bilateral adnexa to remove a large ovarian cyst that was also identified on the admission CT scan. On the third postoperative day, she developed abdominal pain and vomiting. CT revealed small bowel obstruction caused by an enterolith expelled from JPDD. Enterotomy was performed to remove the stone. To our knowledge, only three similar cases have been previously reported in Japan.

Use of Noncontrast Computed Tomography and Computed Tomographic Perfusion in Predicting Intracerebral Hemorrhage After Intravenous Alteplase Therapy.

PubMed

Batchelor, Connor; Pordeli, Pooneh; d'Esterre, Christopher D; Najm, Mohamed; Al-Ajlan, Fahad S; Boesen, Mari E; McDougall, Connor; Hur, Lisa; Fainardi, Enrico; Shankar, Jai Jai Shiva; Rubiera, Marta; Khaw, Alexander V; Hill, Michael D; Demchuk, Andrew M; Sajobi, Tolulope T; Goyal, Mayank; Lee, Ting-Yim; Aviv, Richard I; Menon, Bijoy K

2017-06-01

Intracerebral hemorrhage is a feared complication of intravenous alteplase therapy in patients with acute ischemic stroke. We explore the use of multimodal computed tomography in predicting this complication. All patients were administered intravenous alteplase with/without intra-arterial therapy. An age- and sex-matched case-control design with classic and conditional logistic regression techniques was chosen for analyses. Outcome was parenchymal hemorrhage on 24- to 48-hour imaging. Exposure variables were imaging (noncontrast computed tomography hypoattenuation degree, relative volume of very low cerebral blood volume, relative volume of cerebral blood flow ≤7 mL/min·per 100 g, relative volume of T max ≥16 s with all volumes standardized to z axis coverage, mean permeability surface area product values within T max ≥8 s volume, and mean permeability surface area product values within ipsilesional hemisphere) and clinical variables (NIHSS [National Institutes of Health Stroke Scale], onset to imaging time, baseline systolic blood pressure, blood glucose, serum creatinine, treatment type, and reperfusion status). One-hundred eighteen subjects (22 patients with parenchymal hemorrhage versus 96 without, median baseline NIHSS score of 15) were included in the final analysis. In multivariable regression, noncontrast computed tomography hypoattenuation grade ( P <0.006) and computerized tomography perfusion white matter relative volume of very low cerebral blood volume ( P =0.04) were the only significant variables associated with parenchymal hemorrhage on follow-up imaging (area under the curve, 0.73; 95% confidence interval, 0.63-0.83). Interrater reliability for noncontrast computed tomography hypoattenuation grade was moderate (κ=0.6). Baseline hypoattenuation on noncontrast computed tomography and very low cerebral blood volume on computerized tomography perfusion are associated with development of parenchymal hemorrhage in patients with acute ischemic stroke receiving intravenous alteplase. © 2017 American Heart Association, Inc.

Use of radiography, computed tomography and magnetic resonance imaging for evaluation of navicular syndrome in the horse.

PubMed

Widmer, W R; Buckwalter, K A; Fessler, J F; Hill, M A; VanSickle, D C; Ivancevich, S

2000-01-01

Radiographic evaluation of navicular syndrome is problematic because of its inconsistent correlation with clinical signs. Scintigraphy often yields false positive and false negative results and diagnostic ultrasound is of limited value. Therefore, we assessed the use of computed tomography and magnetic resonance imaging in a horse with clinical and radiographic signs of navicular syndrome. Cadaver specimens were examined with spiral computed tomographic and high-field magnetic resonance scanners and images were correlated with pathologic findings. Radiographic changes consisted of bony remodeling, which included altered synovial fossae, increased medullary opacity, cyst formation and shape change. These osseous changes were more striking and more numerous on computed tomographic and magnetic resonance images. They were most clearly defined with computed tomography. Many osseous changes seen with computed tomography and magnetic resonance imaging were not radiographically evident. Histologically confirmed soft tissue alterations of the deep digital flexor tendon, impar ligament and marrow were identified with magnetic resonance imaging, but not with conventional radiography. Because of their multiplanar capability and tomographic nature, computed tomography and magnetic resonance imaging surpass conventional radiography for navicular imaging, facilitating earlier, more accurate diagnosis. Current advances in imaging technology should make these imaging modalities available to equine practitioners in the future.

Quantitative Comparison of Virtual Monochromatic Images of Dual Energy Computed Tomography Systems: Beam Hardening Artifact Correction and Variance in Computed Tomography Numbers: A Phantom Study.

PubMed

Wu, Rongli; Watanabe, Yoshiyuki; Satoh, Kazuhiko; Liao, Yen-Peng; Takahashi, Hiroto; Tanaka, Hisashi; Tomiyama, Noriyuki

2018-05-21

The aim of this study was to quantitatively compare the reduction in beam hardening artifact (BHA) and variance in computed tomography (CT) numbers of virtual monochromatic energy (VME) images obtained with 3 dual-energy computed tomography (DECT) systems at a given radiation dose. Five different iodine concentrations were scanned using dual-energy and single-energy (120 kVp) modes. The BHA and CT number variance were evaluated. For higher iodine concentrations, 40 and 80 mgI/mL, BHA on VME imaging was significantly decreased when the energy was higher than 50 keV (P = 0.003) and 60 keV (P < 0.001) for GE, higher than 80 keV (P < 0.001) and 70 keV (P = 0.002) for Siemens, and higher than 40 keV (P < 0.001) and 60 keV (P < 0.001) for Toshiba, compared with single-energy CT imaging. Virtual monochromatic energy imaging can decrease BHA and improve CT number accuracy in different dual-energy computed tomography systems, depending on energy levels and iodine concentrations.

Virtopsy: postmortem imaging of laryngeal foreign bodies.

PubMed

Oesterhelweg, Lars; Bolliger, Stephan A; Thali, Michael J; Ross, Steffen

2009-05-01

Death from corpora aliena in the larynx is a well-known entity in forensic pathology. The correct diagnosis of this cause of death is difficult without an autopsy, and misdiagnoses by external examination alone are common. To determine the postmortem usefulness of modern imaging techniques in the diagnosis of foreign bodies in the larynx, multislice computed tomography, magnetic resonance imaging, and postmortem full-body computed tomography-angiography were performed. Three decedents with a suspected foreign body in the larynx underwent the 3 different imaging techniques before medicolegal autopsy. Multislice computed tomography has a high diagnostic value in the noninvasive localization of a foreign body and abnormalities in the larynx. The differentiation between neoplasm or soft foreign bodies (eg, food) is possible, but difficult, by unenhanced multislice computed tomography. By magnetic resonance imaging, the discrimination of the soft tissue structures and soft foreign bodies is much easier. In addition to the postmortem multislice computed tomography, the combination with postmortem angiography will increase the diagnostic value. Postmortem, cross-sectional imaging methods are highly valuable procedures for the noninvasive detection of corpora aliena in the larynx.

Computed tomography in the management of orbital infections associated with dental disease.

PubMed Central

Flood, T. P.; Braude, L. S.; Jampol, L. M.; Herzog, S.

1982-01-01

Two patients developed orbital infection secondary to dental infections. In one patient the infection spread from maxillary premolar and molar teeth to the infratemporal and pterygopalatine fossa and then through the inferior orbital fissure to the subperiosteal space. A subperiosteal abscess in the posterior orbital wall developed, which subsequently spread within the muscle cone. In the second patient infection of an anterior maxillary tooth caused a pansinusitis and unilateral orbital cellulitis. In both patients computed tomographic scanning of the orbit proved valuable in localising the infection and, in one case, planning a surgical approach to the orbit. The infection in both patients responded to treatment, with no permanent visual impairment. Appropriate antibiotics and prompt identification and surgical drainage of orbital abscesses are essential for the preservation of vision in cases of orbital infection. Images PMID:7066283

Leg CT scan

MedlinePlus

CAT scan - leg; Computed axial tomography scan - leg; Computed tomography scan - leg; CT scan - leg ... CT scan makes detailed pictures of the body very quickly. The test may help look for: An abscess ...

Arm CT scan

MedlinePlus

CAT scan - arm; Computed axial tomography scan - arm; Computed tomography scan - arm; CT scan - arm ... Healing problems or scar tissue following surgery A CT scan may also be used to guide a surgeon ...

USE OF COMPUTED TOMOGRAPHY FOR INVESTIGATION OF HEPATIC LIPIDOSIS IN CAPTIVE CHELONOIDIS CARBONARIA (SPIX, 1824).

PubMed

Marchiori, Adriano; da Silva, Ieverton Cleiton Correia; de Albuquerque Bonelli, Marília; de Albuquerque Zanotti, Luciana Carla Rameh; Siqueira, Daniel B; Zanotti, Alexandre Pinheiro; Costa, Fabiano Séllos

2015-06-01

Computed tomography is a sensitive and highly applicable technique for determining the degree of radiographic attenuation of the hepatic parenchyma. Radiodensity measurements of the liver can help in the diagnosis of hepatic lipidosis in humans and animals. The objective was to investigate the presence of hepatic lipidosis in captive red-footed tortoises (Chelonoidis carbonaria) using computed tomography. Computed tomography was performed in 10 male red-footed tortoises. Mean radiographic attenuation values for the hepatic parenchyma were 11.2±3.0 Hounsfield units (HU). Seven red-footed tortoises had values lower than 20 HU, which is compatible with C. carbonaria hepatic lipidosis. These results allowed an early diagnosis of the hepatic changes and suggested corrective measures regarding feeding and management protocols.

Multidetector Computed Tomography for Congenital Anomalies of the Aortic Arch: Vascular Rings.

PubMed

García-Guereta, Luis; García-Cerro, Estefanía; Bret-Zurita, Montserrat

2016-07-01

The development of multidetector computed tomography has triggered a revolution in the study of the aorta and other large vessels and has replaced angiography in the diagnosis of congenital anomalies of the aortic arch, particularly vascular rings. The major advantage of multidetector computed tomography is that it permits clear 3-dimensional assessment of not only vascular structures, but also airway and esophageal compression. The current update aims to summarize the embryonic development of the aortic arch and the developmental anomalies leading to vascular ring formation and to discuss the current diagnostic and therapeutic role of multidetector computed tomography in this field. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Role of (18)F-FDG PET-CT in Monitoring the Cyclophosphamide Induced Pulmonary Toxicity in Patients with Breast Cancer - 2 Case Reports.

PubMed

Taywade, Sameer Kamalakar; Kumar, Rakesh; Bhethanabhotla, Sainath; Bal, Chandrasekhar

2016-09-01

Drug induced pulmonary toxicity is not uncommon with the use of various chemotherapeutic agents. Cyclophosphamide is a widely used chemotherapeutic drug in the treatment of breast cancer. Although rare, lung toxicity has been reported with cyclophosphamide use. Detection of bleomycin induced pulmonary toxicity and pattern of (18)F-fluorodeoxyglucose ((18)F-FDG) uptake in lungs on fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG PET-CT) has been elicited in literature in relation to lymphoma. However, limited data is available regarding the role of (18)F-FDG PET-CT in monitoring drug induced pulmonary toxicity in breast cancer. We here present two cases of cyclophosphamide induced drug toxicity. Interim (18)F-FDG PET-CT demonstrated diffusely increased tracer uptake in bilateral lung fields in both these patients. Subsequently there was resolution of lung uptake on (18)F-FDG PET-CT scan post completion of chemotherapy. These patients did not develop significant respiratory symptoms during chemotherapy treatment and in follow up.

Imaging of the interaction of low frequency electric fields with biological tissues by optical coherence tomography

NASA Astrophysics Data System (ADS)

Peña, Adrian F.; Devine, Jack; Doronin, Alexander; Meglinski, Igor

2014-03-01

We report the use of conventional Optical Coherence Tomography (OCT) for visualization of propagation of low frequency electric field in soft biological tissues ex vivo. To increase the overall quality of the experimental images an adaptive Wiener filtering technique has been employed. Fourier domain correlation has been subsequently applied to enhance spatial resolution of images of biological tissues influenced by low frequency electric field. Image processing has been performed on Graphics Processing Units (GPUs) utilizing Compute Unified Device Architecture (CUDA) framework in the frequencydomain. The results show that variation in voltage and frequency of the applied electric field relates exponentially to the magnitude of its influence on biological tissue. The magnitude of influence is about twice more for fresh tissue samples in comparison to non-fresh ones. The obtained results suggest that OCT can be used for observation and quantitative evaluation of the electro-kinetic changes in biological tissues under different physiological conditions, functional electrical stimulation, and potentially can be used non-invasively for food quality control.

Mechanics of kinetochore microtubules and their interactions with chromosomes during cell division

NASA Astrophysics Data System (ADS)

Nazockdast, Ehssan; Fürthauer, Sebastian; Redemann, Stephanie; Baumgart, Johannes; Lindow, Norbert; Kratz, Andrea; Prohaska, Steffen; Müller-Reichert, Thomas; Shelley, Michael

2016-11-01

The accurate segregation of chromosomes, and subsequent cell division, in Eukaryotic cells is achieved by the interactions of an assembly of microtubules (MTs) and motor-proteins, known as the mitotic spindle. We use a combination of our computational platform for simulating cytoskeletal assemblies and our structural data from high-resolution electron tomography of the mitotic spindle, to study the kinetics and mechanics of MTs in the spindle, and their interactions with chromosomes during chromosome segregation in the first cell division in C.elegans embryo. We focus on kinetochore MTs, or KMTs, which have one end attached to a chromosome. KMTs are thought to be a key mechanical component in chromosome segregation. Using exploratory simulations of MT growth, bending, hydrodynamic interactions, and attachment to chromosomes, we propose a mechanical model for KMT-chromosome interactions that reproduces observed KMT length and shape distributions from electron tomography. We find that including detailed hydrodynamic interactions between KMTs is essential for agreement with the experimental observations.

Handheld single photon emission computed tomography (handheld SPECT) navigated video-assisted thoracoscopic surgery of computer tomography-guided radioactively marked pulmonary lesions.

PubMed

Müller, Joachim; Putora, Paul Martin; Schneider, Tino; Zeisel, Christoph; Brutsche, Martin; Baty, Florent; Markus, Alexander; Kick, Jochen

2016-09-01

Radioactive marking can be a valuable extension to minimally invasive surgery. The technique has been clinically applied in procedures involving sentinel lymph nodes, parathyroidectomy as well as interventions in thoracic surgery. Improvements in equipment and techniques allow one to improve the limits. Pulmonary nodules are frequently surgically removed for diagnostic or therapeutic reasons; here video-assisted thoracoscopic surgery (VATS) is the preferred technique. VATS might be impossible with nodules that are small or located deep in the lung. In this study, we examined the clinical application and safety of employing the newly developed handheld single photon emission tomography (handheld SPECT) device in combination with CT-guided radioactive marking of pulmonary nodules. In this pilot study, 10 subjects requiring surgical resection of a pulmonary nodule were included. The technique involved CT-guided marking of the target nodule with a 20-G needle, with subsequent injection of 25-30 MBq (effective: 7-14 MBq) Tc-99m MAA (Macro Albumin Aggregate). Quality control was made with conventional SPECT-CT to confirm the correct localization and exclude possible complications related to the puncture procedure. VATS was subsequently carried out using the handheld SPECT to localize the radioactivity intraoperatively and therefore the target nodule. A 3D virtual image was superimposed on the intraoperative visual image for surgical guidance. In 9 of the 10 subjects, the radioactive application was successfully placed directly in or in the immediate vicinity of the target nodule. The average size of the involved nodules was 9 mm (range 4-15). All successfully marked nodules were subsequently completely excised (R0) using VATS. The procedure was well tolerated. An asymptomatic clinically insignificant pneumothorax occurred in 5 subjects. Two subjects were found to have non-significant discrete haemorrhage in the infiltration canal of the needle. In a single subject, the radioactive marking was unsuccessful because the radioactivity spread into the pleural space. In our series of 10 patients, it was demonstrated that using handheld SPECT in conjunction with VATS to remove radioactively marked pulmonary nodules is feasible. The combination of proven surgical techniques with a novel localization device (handheld SPECT) allowed successful VATS excision of pulmonary nodules which, due to their localization and small size, would typically have required thoracotomy. ClinicalTrials.gov, NCT02050724, Public 01/29/214, Joachim Müller. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Comprehensive Digital Imaging Network Project At Georgetown University Hospital

NASA Astrophysics Data System (ADS)

Mun, Seong K.; Stauffer, Douglas; Zeman, Robert; Benson, Harold; Wang, Paul; Allman, Robert

1987-10-01

The radiology practice is going through rapid changes due to the introduction of state-of-the-art computed based technologies. For the last twenty years we have witnessed the introduction of many new medical diagnostic imaging systems such as x-ray computed tomo-graphy, digital subtraction angiography (DSA), computerized nuclear medicine, single pho-ton emission computed tomography (SPECT), positron emission tomography (PET) and more re-cently, computerized digital radiography and nuclear magnetic resonance imaging (MRI). Other than the imaging systems, there has been a steady introduction of computed based information systems for radiology departments and hospitals.

Utility of three-dimensional and multiplanar reformatted computed tomography for evaluation of pediatric congenital spine abnormalities.

PubMed

Newton, Peter O; Hahn, Gregory W; Fricka, Kevin B; Wenger, Dennis R

2002-04-15

A retrospective radiographic review of 31 patients with congenital spine abnormalities who underwent conventional radiography and advanced imaging studies was conducted. To analyze the utility of three-dimensional computed tomography with multiplanar reformatted images for congenital spine anomalies, as compared with plain radiographs and axial two-dimensional computed tomography imaging. Conventional radiographic imaging for congenital spine disorders often are difficult to interpret because of the patient's small size, the complexity of the disorder, a deformity not in the plane of the radiographs, superimposed structures, and difficulty in forming a mental three-dimensional image. Multiplanar reformatted and three-dimensional computed tomographic imaging offers many potential advantages for defining congenital spine anomalies including visualization of the deformity in any plane, from any angle, with the overlying structures subtracted. The imaging studies of patients who had undergone a three-dimensional computed tomography for congenital deformities of the spine between 1992 and 1998 were reviewed (31 cases). All plain radiographs and axial two-dimensional computed tomography images performed before the three-dimensional computed tomography were reviewed and the findings documented. This was repeated for the three-dimensional reconstructions and, when available, the multiplanar reformatted images (15 cases). In each case, the utility of the advanced imaging was graded as one of the following: Grade A (substantial new information obtained), Grade B (confirmatory with improved visualization and understanding of the deformity), and Grade C (no added useful information obtained). In 17 of 31 cases, the multiplanar reformatted and three-dimensional images allowed identification of unrecognized malformations. In nine additional cases, the advanced imaging was helpful in better visualizing and understanding previously identified deformities. In five cases, no new information was gained. The standard and curved multiplanar reformatted images were best for defining the occiput-C1-C2 anatomy and the extent of segmentation defects. The curved multiplanar reformatted images were especially helpful in keeping the spine from "coming in" and "going out" of the plane of the image when there was significant spine deformity in the sagittal or coronal plane. The three-dimensional reconstructions proved valuable in defining failures of formation. Advanced computed tomography imaging (three-dimensional computed tomography and curved/standard multiplanar reformatted images) allows better definition of congenital spine anomalies. More than 50% of the cases showed additional abnormalities not appreciated on plain radiographs or axial two-dimensional computed tomography images. Curved multiplanar reformatted images allowed imaging in the coronal and sagittal planes of the entire deformity.

Heart CT scan

MedlinePlus

... Computed tomography scan - heart; Calcium scoring; Multi-detector CT scan - heart; Electron beam computed tomography - heart; Agatston ... table that slides into the center of the CT scanner. You will lie on your back with ...

Directional sinogram interpolation for sparse angular acquisition in cone-beam computed tomography.

PubMed

Zhang, Hua; Sonke, Jan-Jakob

2013-01-01

Cone-beam (CB) computed tomography (CT) is widely used in the field of medical imaging for guidance. Inspired by Betram's directional interpolation (BDI) methods, directional sinogram interpolation (DSI) was implemented to generate more CB projections by optimized (iterative) double-orientation estimation in sinogram space and directional interpolation. A new CBCT was subsequently reconstructed with the Feldkamp algorithm using both the original and interpolated CB projections. The proposed method was evaluated on both phantom and clinical data, and image quality was assessed by correlation ratio (CR) between the interpolated image and a gold standard obtained from full measured projections. Additionally, streak artifact reduction and image blur were assessed. In a CBCT reconstructed by 40 acquired projections over an arc of 360 degree, streak artifacts dropped 20.7% and 6.7% in a thorax phantom, when our method was compared to linear interpolation (LI) and BDI methods. Meanwhile, image blur was assessed by a head-and-neck phantom, where image blur of DSI was 20.1% and 24.3% less than LI and BDI. When our method was compared to LI and DI methods, CR increased by 4.4% and 3.1%. Streak artifacts of sparsely acquired CBCT were decreased by our method and image blur induced by interpolation was constrained to below other interpolation methods.

X-ray computed tomography comparison of individual and parallel assembled commercial lithium iron phosphate batteries at end of life after high rate cycling

NASA Astrophysics Data System (ADS)

Carter, Rachel; Huhman, Brett; Love, Corey T.; Zenyuk, Iryna V.

2018-03-01

X-ray computed tomography (X-ray CT) across multiple length scales is utilized for the first time to investigate the physical abuse of high C-rate pulsed discharge on cells wired individually and in parallel.. Manufactured lithium iron phosphate cells boasting high rate capability were pulse power tested in both wiring conditions with high discharge currents of 10C for a high number of cycles (up to 1200) until end of life (<80% of initial discharge capacity retained). The parallel assembly reached end of life more rapidly for reasons unknown prior to CT investigations. The investigation revealed evidence of overdischarge in the most degraded cell from the parallel assembly, compared to more traditional failure in the individual cell. The parallel-wired cell exhibited dissolution of copper from the anode current collector and subsequent deposition throughout the separator near the cathode of the cell. This overdischarge-induced copper deposition, notably impossible to confirm with other state of health (SOH) monitoring methods, is diagnosed using CT by rendering the interior current collector without harm or alteration to the active materials. Correlation of CT observations to the electrochemical pulse data from the parallel-wired cells reveals the risk of parallel wiring during high C-rate pulse discharge.

Detection and distribution analysis of organosilicon compounds in wood by means of SEM-EDX and micro-CT

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

Vetter, L. de; Cnudde, V.; Masschaele, B.

This article explores the potential of a scanning electron microscope with an energy dispersive X-ray spectrometer in combination with a new non-destructive 3D visualization technique, X-ray micro-computed tomography, as detection methods for siloxanes/silanes mixtures applied as wood preservatives. In order to have a higher contrast, bromine functional silane was added to the mixture. Scots pine and beech samples were dipped or impregnated with the mixture and subsequently scanned. Both silicon and bromine were easily detectable with both techniques. Dipped siloxanes/silanes covered the cell walls partly in beech and the lumen partly or completely in Scots pine. Impregnated siloxanes/silanes could bemore » found in the cell walls of both wood species. From the results, it can be concluded that, under the circumstances as described in the article, impregnation with a siloxane is necessary to have cell wall penetration. The combination of scanning electron microscopy, energy dispersive X-ray spectroscopy and micro-computed tomography can offer important information concerning the localization of certain products inside wood. While the last of these can monitor changes in 3D, the other two techniques can provide detailed 2D information. Both techniques are complementary and provide important extra information.« less

Characteristics of Rib Fractures in Child Abuse-The Role of Low-Dose Chest Computed Tomography.

PubMed

Sanchez, Thomas R; Grasparil, Angelo D; Chaudhari, Ruchir; Coulter, Kevin P; Wootton-Gorges, Sandra L

2018-02-01

Our aim is to describe the radiologic characteristics of rib fractures in clinically diagnosed cases of child abuse and suggest a complementary imaging for radiographically occult injuries in highly suspicious cases of child abuse. Retrospective analysis of initial and follow-up skeletal surveys and computed tomography (CT) scans of 16 patients younger than 12 months were reviewed after obtaining approval from our institutional review board. The number, location, displacement, and age of the rib fractures were recorded. Out of a total 105 rib fractures, 84% (87/105) were detected on the initial skeletal survey. Seventeen percent (18/105) were seen only after follow-up imaging, more than half of which (11/18) were detected on a subsequent CT. Majority of the fractures were posterior (43%) and anterior (30%) in location. An overwhelming majority (96%) of the fractures are nondisplaced. Seventeen percent of rib fractures analyzed in the study were not documented on the initial skeletal survey. Majority of fractures are nondisplaced and located posteriorly or anteriorly, areas that are often difficult to assess especially in the acute stage. The CT scan is more sensitive in evaluating these types of fractures. Low-dose chest CT can be an important imaging modality for suspicious cases of child abuse when initial radiographic findings are inconclusive.

Advanced measurement techniques to characterize thermo-mechanical aspects of solid oxide fuel cells

NASA Astrophysics Data System (ADS)

Malzbender, J.; Steinbrech, R. W.

Advanced characterization methods have been used to analyze the thermo-mechanical behaviour of solid oxide fuel cells in a model stack. The primarily experimental work included contacting studies, sealing of a model stack, thermal and re-oxidation cycling. Also an attempt was made to correlate cell fracture in the stack with pore sizes determined from computer tomography. The contacting studies were carried out using pressure sensitive foils. The load to achieve full contact on anode and cathode side of the cell was assessed and applied in the subsequent model stack test. The stack experiment permitted a detailed analysis of stack compaction during sealing. During steady state operation thermal and re-oxidation cycling the changes in open cell voltage and acoustic emissions were monitored. Significant softening of the sealant material was observed at low temperatures. Heating in the thermal cycling loop of the stack appeared to be less critical than the cooling. Re-oxidation cycling led to significant damage if a critical re-oxidation time was exceeded. Microstructural studies permitted further insight into the re-oxidation mechanism. Finally, the maximum defect size in the cell was determined by computer tomography. A limit of maximum anode stress was estimated and the result correlated this with the failure strength observed during the model stack testing.

Volume adjustment of lung density by computed tomography scans in patients with emphysema.

PubMed

Shaker, S B; Dirksen, A; Laursen, L C; Skovgaard, L T; Holstein-Rathlou, N H

2004-07-01

To determine how to adjust lung density measurements for the volume of the lung calculated from computed tomography (CT) scans in patients with emphysema. Fifty patients with emphysema underwent 3 CT scans at 2-week intervals. The scans were analyzed with a software package that detected the lung in contiguous images and subsequently generated a histogram of the pixel attenuation values. The total lung volume (TLV), lung weight, percentile density (PD), and relative area of emphysema (RA) were calculated from this histogram. RA and PD are commonly applied measures of pulmonary emphysema derived from CT scans. These parameters are markedly influenced by changes in the level of inspiration. The variability of lung density due to within-subject variation in TLV was explored by plotting TLV against PD and RA. The coefficients for volume adjustment for PD were relatively stable over a wide range from the 10th to the 80th percentile, whereas for RA the coefficients showed large variability especially in the lower range, which is the most relevant for quantitation of pulmonary emphysema. Volume adjustment is mandatory in repeated CT densitometry and is more robust for PD than for RA. Therefore, PD seems more suitable for monitoring the progression of emphysema.

Smoking-related interstitial fibrosis combined with pulmonary emphysema: computed tomography-pathologic correlative study using lobectomy specimens.

PubMed

Otani, Hideji; Tanaka, Tomonori; Murata, Kiyoshi; Fukuoka, Junya; Nitta, Norihisa; Nagatani, Yukihiro; Sonoda, Akinaga; Takahashi, Masashi

2016-01-01

To evaluate the incidence and pathologic correlation of thin-section computed tomography (TSCT) findings in smoking-related interstitial fibrosis (SRIF) with pulmonary emphysema. Our study included 172 consecutive patients who underwent TSCT and subsequent lobectomy. TSCT findings including clustered cysts with visible walls (CCVW) and ground-glass attenuation with/without reticulation (GGAR) were evaluated and compared in nonsmokers and smokers and among lung locations. TSCT findings, especially CCVW, were also compared with histological findings using lobectomy specimens. The incidence of CCVW and GGAR was significantly higher in smokers than in nonsmokers (34.1% and 40.7%, respectively, vs 2.0% and 12.2%). CCVW and GGAR were frequently found in the lower and peripheral zones. Histologically, CCVW corresponded more often with SRIF with emphysema than usual interstitial pneumonia (UIP, 63.3% vs 30%). CCVW of irregular size and shape were seen in 19 of 20 SRIF with emphysema and in seven of nine UIP-manifested areas with similar round cysts. A less-involved subpleural parenchyma was observed more frequently in SRIF with emphysema. SRIF with emphysema is a more frequent pathological finding than UIP in patients with CCVW on TSCT. The irregular size and shape of CCVW and a less-involved subpleural parenchyma may be a clue suggesting the presence of SRIF with emphysema.

A rare case of pure primary hemangioma of the scapula: A case report

PubMed Central

LI, WEI; ZOU, FAN; DAI, MIN; ZHANG, BIN; NIE, TAO

2015-01-01

Hemangioma is a benign vascular tumor, which may occur in any bone of the body. The most common locations are the spine and craniofacial bone; however, occurrence is extremely rare in the scapula. The current study presented the case of a 58-year-old female, with scapula hemangioma in the left shoulder who presented with joint ache that had lasted for ~1 year. The main clinical manifestations included local tenderness, an osseous lump and limited shoulder movement with a little pain, which was alleviated by rest. Roentgenogram, computed tomography and magnetic resonance imaging of the left acromion revealed a mass along the inner surface of the scapula of the left shoulder with polycystic expansion and bone destruction. The results of computed tomography and magnetic resonance imaging indicated a pure primary tumor and the lesion was subsequently resected. Notably, the postoperative pathological diagnosis was capillary hemangioma. The aim of the present study was to analyze the clinical and imaging features of scapula hemangioma, which must be considered for the differential diagnosis of scapula tumors. In the present case, no recurrence was identified by X-ray examination 1 year after surgery. The long-term efficacy of surgical treatment requires continuous observation of the patient. PMID:26622831

Penalized weighted least-squares approach for multienergy computed tomography image reconstruction via structure tensor total variation regularization.

PubMed

Zeng, Dong; Gao, Yuanyuan; Huang, Jing; Bian, Zhaoying; Zhang, Hua; Lu, Lijun; Ma, Jianhua

2016-10-01

Multienergy computed tomography (MECT) allows identifying and differentiating different materials through simultaneous capture of multiple sets of energy-selective data belonging to specific energy windows. However, because sufficient photon counts are not available in each energy window compared with that in the whole energy window, the MECT images reconstructed by the analytical approach often suffer from poor signal-to-noise and strong streak artifacts. To address the particular challenge, this work presents a penalized weighted least-squares (PWLS) scheme by incorporating the new concept of structure tensor total variation (STV) regularization, which is henceforth referred to as 'PWLS-STV' for simplicity. Specifically, the STV regularization is derived by penalizing higher-order derivatives of the desired MECT images. Thus it could provide more robust measures of image variation, which can eliminate the patchy artifacts often observed in total variation (TV) regularization. Subsequently, an alternating optimization algorithm was adopted to minimize the objective function. Extensive experiments with a digital XCAT phantom and meat specimen clearly demonstrate that the present PWLS-STV algorithm can achieve more gains than the existing TV-based algorithms and the conventional filtered backpeojection (FBP) algorithm in terms of both quantitative and visual quality evaluations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Segmentation of 3D ultrasound computer tomography reflection images using edge detection and surface fitting

NASA Astrophysics Data System (ADS)

Hopp, T.; Zapf, M.; Ruiter, N. V.

2014-03-01

An essential processing step for comparison of Ultrasound Computer Tomography images to other modalities, as well as for the use in further image processing, is to segment the breast from the background. In this work we present a (semi-) automated 3D segmentation method which is based on the detection of the breast boundary in coronal slice images and a subsequent surface fitting. The method was evaluated using a software phantom and in-vivo data. The fully automatically processed phantom results showed that a segmentation of approx. 10% of the slices of a dataset is sufficient to recover the overall breast shape. Application to 16 in-vivo datasets was performed successfully using semi-automated processing, i.e. using a graphical user interface for manual corrections of the automated breast boundary detection. The processing time for the segmentation of an in-vivo dataset could be significantly reduced by a factor of four compared to a fully manual segmentation. Comparison to manually segmented images identified a smoother surface for the semi-automated segmentation with an average of 11% of differing voxels and an average surface deviation of 2mm. Limitations of the edge detection may be overcome by future updates of the KIT USCT system, allowing a fully-automated usage of our segmentation approach.

Iterative image reconstruction for multienergy computed tomography via structure tensor total variation regularization

NASA Astrophysics Data System (ADS)

Zeng, Dong; Bian, Zhaoying; Gong, Changfei; Huang, Jing; He, Ji; Zhang, Hua; Lu, Lijun; Feng, Qianjin; Liang, Zhengrong; Ma, Jianhua

2016-03-01

Multienergy computed tomography (MECT) has the potential to simultaneously offer multiple sets of energy- selective data belonging to specific energy windows. However, because sufficient photon counts are not available in the specific energy windows compared with that in the whole energy window, the MECT images reconstructed by the analytical approach often suffer from poor signal-to-noise (SNR) and strong streak artifacts. To eliminate this drawback, in this work we present a penalized weighted least-squares (PWLS) scheme by incorporating the new concept of structure tensor total variation (STV) regularization to improve the MECT images quality from low-milliampere-seconds (low-mAs) data acquisitions. Henceforth the present scheme is referred to as `PWLS- STV' for simplicity. Specifically, the STV regularization is derived by penalizing the eigenvalues of the structure tensor of every point in the MECT images. Thus it can provide more robust measures of image variation, which can eliminate the patchy artifacts often observed in total variation regularization. Subsequently, an alternating optimization algorithm was adopted to minimize the objective function. Experiments with a digital XCAT phantom clearly demonstrate that the present PWLS-STV algorithm can achieve more gains than the existing TV-based algorithms and the conventional filtered backpeojection (FBP) algorithm in terms of noise-induced artifacts suppression, resolution preservation, and material decomposition assessment.

Evaluation of 3D airway imaging of obstructive sleep apnea with cone-beam computed tomography.

PubMed

Ogawa, Takumi; Enciso, Reyes; Memon, Ahmed; Mah, James K; Clark, Glenn T

2005-01-01

This study evaluates the use of cone-beam Computer Tomography (CT) for imaging the upper airway structure of Obstructive Sleep Apnea (OSA) patients. The total airway volume and the anteroposterior dimension of oropharyngeal airway showed significant group differences between OSA and gender-matched controls, so if we increase sample size these measurements may distinguish the two groups. We demonstrate the utility of diagnosis of anatomy with the 3D airway imaging with cone-beam Computed Tomography.

Cone beam computed tomography in Endodontics - a review.

PubMed

Patel, S; Durack, C; Abella, F; Shemesh, H; Roig, M; Lemberg, K

2015-01-01

Cone beam computed tomography (CBCT) produces undistorted three-dimensional information of the maxillofacial skeleton, including the teeth and their surrounding tissues with a lower effective radiation dose than computed tomography. The aim of this paper is to: (i) review the current literature on the applications and limitations of CBCT; (ii) make recommendations for the use of CBCT in Endodontics; (iii) highlight areas of further research of CBCT in Endodontics. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

White Paper of the Society of Computed Body Tomography and Magnetic Resonance on Dual-Energy CT, Part 1: Technology and Terminology.

PubMed

Siegel, Marilyn J; Kaza, Ravi K; Bolus, David N; Boll, Daniel T; Rofsky, Neil M; De Cecco, Carlo N; Foley, W Dennis; Morgan, Desiree E; Schoepf, U Joseph; Sahani, Dushyant V; Shuman, William P; Vrtiska, Terri J; Yeh, Benjamin M; Berland, Lincoln L

This is the first of a series of 4 white papers that represent Expert Consensus Documents developed by the Society of Computed Body Tomography and Magnetic Resonance through its task force on dual-energy computed tomography (DECT). This article, part 1, describes the fundamentals of the physical basis for DECT and the technology of DECT and proposes uniform nomenclature to account for differences in proprietary terms among manufacturers.

[Cardiac computed tomography: new applications of an evolving technique].

PubMed

Martín, María; Corros, Cecilia; Calvo, Juan; Mesa, Alicia; García-Campos, Ana; Rodríguez, María Luisa; Barreiro, Manuel; Rozado, José; Colunga, Santiago; de la Hera, Jesús M; Morís, César; Luyando, Luis H

2015-01-01

During the last years we have witnessed an increasing development of imaging techniques applied in Cardiology. Among them, cardiac computed tomography is an emerging and evolving technique. With the current possibility of very low radiation studies, the applications have expanded and go further coronariography In the present article we review the technical developments of cardiac computed tomography and its new applications. Copyright © 2014 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

Plain X-ray, computed tomography and magnetic resonance imaging findings of telangiectatic osteosarcoma: a case report

PubMed Central

Koutoulidis, Vasilios; Koureas, Andreas; Moulopoulos, Lia; Gouliamos, Athanasios

2009-01-01

An 18-year-old male patient presented with chronic nonspecific pain of three months located at his left proximal tibia. The patient was admitted to our department for plain X-ray, computed tomography and magnetic resonance imaging examination. Plain X-ray and computed tomography revealed a geographic lytic lesion at the medial aspect of the proximal tibia. Biopsy of the lesion showed telangiectatic osteosarcoma. Image findings of all modalities are presented. PMID:19918488

Accuracy and Precision of Radioactivity Quantification in Nuclear Medicine Images

PubMed Central

Frey, Eric C.; Humm, John L.; Ljungberg, Michael

2012-01-01

The ability to reliably quantify activity in nuclear medicine has a number of increasingly important applications. Dosimetry for targeted therapy treatment planning or for approval of new imaging agents requires accurate estimation of the activity in organs, tumors, or voxels at several imaging time points. Another important application is the use of quantitative metrics derived from images, such as the standard uptake value commonly used in positron emission tomography (PET), to diagnose and follow treatment of tumors. These measures require quantification of organ or tumor activities in nuclear medicine images. However, there are a number of physical, patient, and technical factors that limit the quantitative reliability of nuclear medicine images. There have been a large number of improvements in instrumentation, including the development of hybrid single-photon emission computed tomography/computed tomography and PET/computed tomography systems, and reconstruction methods, including the use of statistical iterative reconstruction methods, which have substantially improved the ability to obtain reliable quantitative information from planar, single-photon emission computed tomography, and PET images. PMID:22475429

Chest pain in the emergency room-an interesting case presentation.

PubMed

Turner, Michael C

2016-12-01

A 61-year-old woman presented to the emergency room with atypical chest pain, non-diagnostic electrocardiogram, and an initial troponin level that was normal. A coronary computed tomography angio (CCTA) was performed, and on initial review, it appeared to be normal. Subsequent review including evaluation of functional data from the retrospective scan identified a distal left anterior descending occlusion and an apical wall-motion abnormality with no other evidence of heart disease. This case illustrates the complementary contribution of anatomic and functional data and serves to remind us that on rare occasions, what looks "normal" is not always normal. © 2016, Wiley Periodicals, Inc.

[Complex treatment of patients with cholangiogenic hepatic abscess].

PubMed

Nychytaĭlo, M Iu; Skums, A V; Medvets'kyĭ, Ie B; Ohorodnyk, P V; Mashkovs'kyĭ, H Iu; Shkarban, V P; Shkarban, P O; Farzolakh, Mekhraban Jafarlu

2005-07-01

Results of treatment of 47 patients with cholangiogenic hepatic abscess were analyzed. Clinical, laboratory and special methods of investigation were applied for diagnosis. The authors consider ultrasound investigation (USI), computer tomography and the abscess puncture under the USI control with subsequent cytological and bacterial control the decisive methods in diagnosis of hepatic abscess. In complex of treatment of patients miniinvasive technologies were applied--the abscess puncture, its cavity drainage under USI control transcutaneus transhepatic cholangiostomy, endoscopic papillosphincterotomy with lithotripsy and nasobiliary drainage, according to indications. Efficacy of the abscess cavity sanation, using miramistinum and decasan, was proved. In general therapy the directed transport of medicines was applied.

Anomalous vertebral artery origins: the first and second reports of two variants.

PubMed

Hsu, Daniel P; Alexander, Ashley D; Gilkeson, Robert C

2010-06-01

We present two cases of aberrant origins of vertebral arteries. Case 1 is of a patient undergoing evaluation of an infrarenal aortic aneurysm stent graft. Computed tomography (CT) angiogram revealed an aberrant right vertebral artery that subsequently joined a second right vertebral artery that had the typical origin off the right subclavian artery. This represents an unusual anatomic variation not previously reported in the literature. Case 2 is of a patient being evaluated for thoracic aorta injury. CT angiogram of the chest revealed a five-vessel aortic arch with aberrant origin of the bilateral vertebral arteries distal to the left subclavian artery.

Mesorectum localization as a special kind of rectal metastasis from breast cancer.

PubMed

Xue, Fan; Liu, Zhong-Lin; Zhang, Qing; Kong, Xiang-Nan; Liu, Wen-Zhi

2015-04-14

Breast cancer can metastasize to other organs following initial treatment. Bones, liver, and the lung are the most common sites of breast cancer metastases. The digestive tract, on the other hand, is rarely involved. The incidence of mesorectal metastasis (a special category of rectal metastases) from breast cancer has not been described before. The case reported herein concerns a 68-year-old woman who underwent mastectomy. A pelvic mass with no symptoms was subsequently identified by computed tomography in the patient. We ultimately confirmed that this mass was a metastasis from breast cancer located in the mesorectum using surgical exploration and pathology results.

A giant testicular mixed germ cell tumour.

PubMed

Reekhaye, A; Harris, A; Nagarajan, S; Chadwick, D

2016-11-01

We present a case that we believe to be the largest mixed germ cell testicular tumour reported in the United Kingdom. A 23-year-old male was admitted to our urology department with a large scrotal swelling. The patient was found to have a giant left testicular tumour and a solitary lung metastasis at presentation. He underwent an emergency radical orchidectomy and subsequently received four cycles of bleomycin, etoposide and cisplatin chemotherapy. Four months after starting treatment, the tumour markers had normalised and a repeat staging computed tomography showed no active disease. The tumour reached that size because of the patient's failure to seek medical attention due to fear and embarrassment.

Meaning of Interior Tomography

PubMed Central

Wang, Ge; Yu, Hengyong

2013-01-01

The classic imaging geometry for computed tomography is for collection of un-truncated projections and reconstruction of a global image, with the Fourier transform as the theoretical foundation that is intrinsically non-local. Recently, interior tomography research has led to theoretically exact relationships between localities in the projection and image spaces and practically promising reconstruction algorithms. Initially, interior tomography was developed for x-ray computed tomography. Then, it has been elevated as a general imaging principle. Finally, a novel framework known as “omni-tomography” is being developed for grand fusion of multiple imaging modalities, allowing tomographic synchrony of diversified features. PMID:23912256

Correlation between Preoperative High Resolution Computed Tomography (CT) Findings with Surgical Findings in Chronic Otitis Media (COM) Squamosal Type.

PubMed

Karki, S; Pokharel, M; Suwal, S; Poudel, R

Background The exact role of High resolution computed tomography (HRCT) temporal bone in preoperative assessment of Chronic suppurative otitis media atticoantral disease still remains controversial. Objective To evaluate the role of high resolution computed tomography temporal bone in Chronic suppurative otitis media atticoantral disease and to compare preoperative computed tomographic findings with intra-operative findings. Method Prospective, analytical study conducted among 65 patients with chronic suppurative otitis media atticoantral disease in Department of Radiodiagnosis, Kathmandu University Dhulikhel Hospital between January 2015 to July 2016. The operative findings were compared with results of imaging. The parameters of comparison were erosion of ossicles, scutum, facial canal, lateral semicircular canal, sigmoid and tegmen plate along with extension of disease to sinus tympani and facial recess. Sensitivity, specificity, negative predictive value, positive predictive values were calculated. Result High resolution computed tomography temporal bone offered sensitivity (Se) and specificity (Sp) of 100% for visualization of sigmoid and tegmen plate erosion. The performance of HRCT in detecting malleus (Se=100%, Sp=95.23%), incus (Se=100%,Sp=80.48%) and stapes (Se=96.55%, Sp=71.42%) erosion was excellent. It offered precise information about facial canal erosion (Se=100%, Sp=75%), scutum erosion (Se=100%, Sp=96.87%) and extension of disease to facial recess and sinus tympani (Se=83.33%,Sp=100%). high resolution computed tomography showed specificity of 100% for lateral semicircular canal erosion (Sp=100%) but with low sensitivity (Se=53.84%). Conclusion The findings of high resolution computed tomography and intra-operative findings were well comparable except for lateral semicircular canal erosion. high resolution computed tomography temporal bone acts as a road map for surgeon to identify the extent of disease, plan for appropriate procedure that is required and prepare for potential complications that can be encountered during surgery.

Computer-aided diagnosis for phase-contrast X-ray computed tomography: quantitative characterization of human patellar cartilage with high-dimensional geometric features.

PubMed

Nagarajan, Mahesh B; Coan, Paola; Huber, Markus B; Diemoz, Paul C; Glaser, Christian; Wismüller, Axel

2014-02-01

Phase-contrast computed tomography (PCI-CT) has shown tremendous potential as an imaging modality for visualizing human cartilage with high spatial resolution. Previous studies have demonstrated the ability of PCI-CT to visualize (1) structural details of the human patellar cartilage matrix and (2) changes to chondrocyte organization induced by osteoarthritis. This study investigates the use of high-dimensional geometric features in characterizing such chondrocyte patterns in the presence or absence of osteoarthritic damage. Geometrical features derived from the scaling index method (SIM) and statistical features derived from gray-level co-occurrence matrices were extracted from 842 regions of interest (ROI) annotated on PCI-CT images of ex vivo human patellar cartilage specimens. These features were subsequently used in a machine learning task with support vector regression to classify ROIs as healthy or osteoarthritic; classification performance was evaluated using the area under the receiver-operating characteristic curve (AUC). SIM-derived geometrical features exhibited the best classification performance (AUC, 0.95 ± 0.06) and were most robust to changes in ROI size. These results suggest that such geometrical features can provide a detailed characterization of the chondrocyte organization in the cartilage matrix in an automated and non-subjective manner, while also enabling classification of cartilage as healthy or osteoarthritic with high accuracy. Such features could potentially serve as imaging markers for evaluating osteoarthritis progression and its response to different therapeutic intervention strategies.

Trails on 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Leading to Diagnosis of Testicular Adrenal Rest Tumor.

PubMed

Kashyap, Raghava

2018-01-01

Testicular adrenal rest tumors (TARTs) are secondary to hypertrophy of adrenal rest cells in the rete testis in settings of hypersecretion of androgens. We present a case of congenital adrenal hyperplasia with TART with clues to the diagnosis on 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT). To the best of our knowledge, this is the first reported case on the role of 18 F-FDG PET/CT in TART.

Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography in Disseminated Cryptococcosis.

PubMed

Tripathy, Sarthak; Parida, Girish Kumar; Roy, Shambo Guha; Singhal, Abhinav; Mallick, Saumya Ranjan; Tripathi, Madhavi; Shamim, Shamim Ahmed

2017-01-01

Disseminated cryptococcosis without pulmonary involvement is a very rare phenomenon. Patterns of organ involvement in cryptococcosis resemble various other infective conditions as well as malignant conditions on fluorodeoxyglucose positron emission tomography-computed tomography. We present a case of a 43-year-old male patient who had disseminated cryptococcosis. The rarity of the case being noninvolvement of lungs and meninges and resembling more like lymphoma due to the diffuse involvement of the lymph nodes on both sides of the diaphragm.

CT Perfusion of the Head

MedlinePlus

... News Physician Resources Professions Site Index A-Z CT Perfusion of the Head Computed tomography (CT) perfusion ... of CT Perfusion of the Head? What is CT Perfusion of the Head? Computed tomography (CT) perfusion ...

Quantification of pericardial effusions by echocardiography and computed tomography.

PubMed

Leibowitz, David; Perlman, Gidon; Planer, David; Gilon, Dan; Berman, Philip; Bogot, Naama

2011-01-15

Echocardiography is a well-accepted tool for the diagnosis and quantification of pericardial effusion (PEff). Given the increasing use of computed tomographic (CT) scanning, more PEffs are being initially diagnosed by computed tomography. No study has compared quantification of PEff by computed tomography and echocardiography. The objective of this study was to assess the accuracy of quantification of PEff by 2-dimensional echocardiography and computed tomography compared to the amount of pericardial fluid drained at pericardiocentesis. We retrospectively reviewed an institutional database to identify patients who underwent chest computed tomography and echocardiography before percutaneous pericardiocentesis with documentation of the amount of fluid withdrawn. Digital 2-dimensional echocardiographic and CT images were retrieved and quantification of PEff volume was performed by applying the formula for the volume of a prolate ellipse, π × 4/3 × maximal long-axis dimension/2 × maximal transverse dimension/2 × maximal anteroposterior dimension/2, to the pericardial sac and to the heart. Nineteen patients meeting study qualifications were entered into the study. The amount of PEff drained was 200 to 1,700 ml (mean 674 ± 340). Echocardiographically calculated pericardial effusion volume correlated relatively well with PEff volume (r = 0.73, p <0.001, mean difference -41 ± 225 ml). There was only moderate correlation between CT volume quantification and actual volume drained (r = 0.4, p = 0.004, mean difference 158 ± 379 ml). In conclusion, echocardiography appears a more accurate imaging technique than computed tomography in quantitative assessment of nonloculated PEffs and should continue to be the primary imaging in these patients. Copyright © 2011 Elsevier Inc. All rights reserved.

Development of computational small animal models and their applications in preclinical imaging and therapy research

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

Xie, Tianwu; Zaidi, Habib, E-mail: habib.zaidi@hcuge.ch; Geneva Neuroscience Center, Geneva University, Geneva CH-1205

The development of multimodality preclinical imaging techniques and the rapid growth of realistic computer simulation tools have promoted the construction and application of computational laboratory animal models in preclinical research. Since the early 1990s, over 120 realistic computational animal models have been reported in the literature and used as surrogates to characterize the anatomy of actual animals for the simulation of preclinical studies involving the use of bioluminescence tomography, fluorescence molecular tomography, positron emission tomography, single-photon emission computed tomography, microcomputed tomography, magnetic resonance imaging, and optical imaging. Other applications include electromagnetic field simulation, ionizing and nonionizing radiation dosimetry, and themore » development and evaluation of new methodologies for multimodality image coregistration, segmentation, and reconstruction of small animal images. This paper provides a comprehensive review of the history and fundamental technologies used for the development of computational small animal models with a particular focus on their application in preclinical imaging as well as nonionizing and ionizing radiation dosimetry calculations. An overview of the overall process involved in the design of these models, including the fundamental elements used for the construction of different types of computational models, the identification of original anatomical data, the simulation tools used for solving various computational problems, and the applications of computational animal models in preclinical research. The authors also analyze the characteristics of categories of computational models (stylized, voxel-based, and boundary representation) and discuss the technical challenges faced at the present time as well as research needs in the future.« less

[Computed tomography semiotics of osteonecrosis and sequestration in chronic hematogenic osteomyelitis].

PubMed

D'iachkova, G V; Mitina, Iu L

2007-01-01

Based on the data of computed tomography, radiography and densitometry in 39 patients the authors describe in detail the signs of osteonecrosis and sequestration of different localization and extension.

Pelvic CT scan

MedlinePlus

CAT scan - pelvis; Computed axial tomography scan - pelvis; Computed tomography scan - pelvis; CT scan - pelvis ... Risks of CT scans include: Being exposed to radiation Allergic reaction to contrast dye CT scans do expose you to more radiation ...

Lumbar spine CT scan

MedlinePlus

CAT scan - lumbar spine; Computed axial tomography scan - lumbar spine; Computed tomography scan - lumbar spine; CT - lower back ... CT scans rapidly makes detailed pictures of the lower back. The test may be used to look for: ...

Shoulder CT scan

MedlinePlus

CAT scan - shoulder; Computed axial tomography scan - shoulder; Computed tomography scan - shoulder; CT scan - shoulder ... Risks of CT scans include: Being exposed to radiation Allergic reaction to contrast dye Birth defect if done during pregnancy CT scans ...

SPECT/CT in imaging foot and ankle pathology-the demise of other coregistration techniques.

PubMed

Mohan, Hosahalli K; Gnanasegaran, Gopinath; Vijayanathan, Sanjay; Fogelman, Ignac

2010-01-01

Disorders of the ankle and foot are common and given the complex anatomy and function of the foot, they present a significant clinical challenge. Imaging plays a crucial role in the management of these patients, with multiple imaging options available to the clinician. The American College of radiology has set the appropriateness criteria for the use of the available investigating modalities in the management of foot and ankle pathologies. These are broadly classified into anatomical and functional imaging modalities. Recently, single-photon emission computed tomography and/or computed tomography scanners, which can elegantly combine functional and anatomical images have been introduced, promising an exciting and important development. This review describes our clinical experience with single-photon emission computed tomography and/or computed tomography and discusses potential applications of these techniques.

Comparison of radiological and morphologic assessments of myocardial bridges.

PubMed

Ercakmak, Burcu; Bulut, Elif; Hayran, Mutlu; Kaymaz, Figen; Bilgin, Selma; Hazirolan, Tuncay; Bayramoglu, Alp; Erbil, Mine

2015-09-01

In this study we aimed to compare the findings of coronary dual-source computed tomography angiography of myocardial bridges with cadaveric dissections. Forty-one isolated, non-damaged fresh sheep hearts were used in this study. Myocardial bridges of the anterior interventricular branch of the left coronary artery were demonstrated and analyzed by a coronary dual-source computed tomography angiography. Dissections along the left anterior interventricular branch of the left coronary artery were performed by using Zeiss OPMI pico microscope and the length of the bridges were measured. The depths of the myocardial bridges were measured from the stained sections by using the light microscope (Leica DM 6000B). MBs were found in all 41 hearts (100%) during dissections. Dual-source computed tomography angiography successfully detected 87.8% (36 of the 41 hearts) of the myocardial bridges measured on left anterior interventricular branch of left coronary artery. The lengths of the myocardial bridges were found 5-40 and 8-50 mm with dissection and dual-source computed tomography angiography, respectively. And the depths were found 0.7-4.5 mm by dual-source computed tomography angiography and 0.745-4.632 mm morphologically. Comparison of the mean values of the lengths showed statistically significantly higher values (22.0 ± 8.5, 17.7 ± 7.7 mm, p = 0.003) for the dissections. Radiological assessment also effectively discriminated complete bridges from incomplete ones. Our study showed that coronary computed tomography angiography is reliable in evaluating the presence and depth of myocardial bridges.

Regional lung ventilation and perfusion by electrical impedance tomography compared to single-photon emission computed tomography.

PubMed

Hentze, Benjamin; Muders, Thomas; Luepschen, Henning; Maripuu, Enn; Hedenstierna, Göran; Putensen, Christian; Walter, Marian; Leonhardt, Steffen

2018-06-20

Electrical impedance tomography (EIT) is a noninvasive imaging modality that allows real-time monitoring of regional lung ventilation ([Formula: see text]) in intensive care patients at bedside. However, for improved guidance of ventilation therapy it would be beneficial to obtain regional ventilation-to-perfusion ratio ([Formula: see text]) by EIT. In order to further explore the feasibility, we first evaluate a model-based approach, based on semi-negative matrix factorization and a gamma-variate model, to extract regional lung perfusion ([Formula: see text]) from EIT measurements. Subsequently, a combined validation of both [Formula: see text] and [Formula: see text] measured by EIT against single-photon emission computed tomography (SPECT) is performed on data acquired as part of a porcine animal trial. Four pigs were ventilated at two different levels of positive end-expiratory pressure (PEEP 0 and 15 cm H 2 O, respectively) in randomized order. Repeated injections of an EIT contrast agent (NaCl 10%) and simultaneous SPECT measurements of [Formula: see text] (81 m Kr gas) and [Formula: see text] (99 m Tc-labeled albumin) were performed. Both [Formula: see text] and [Formula: see text] from EIT and SPECT were compared by correlation analysis. Very strong (r 2   =  0.94 to 0.95) correlations were found for [Formula: see text] and [Formula: see text] in the dorsal-ventral direction at both PEEP levels. Moderate (r 2   =  0.36 to 0.46) and moderate to strong (r 2   =  0.61 to 0.82) correlations resulted for [Formula: see text] and [Formula: see text] in the right-left direction, respectively. The results of combined validation indicate that monitoring of [Formula: see text] and [Formula: see text] by EIT is possible. However, care should be taken when trying to quantify [Formula: see text] by EIT, as imaging artefacts and model bias may void necessary spatial matching.

False-Positive [18F]fluorodeoxyglucose-avid lymph nodes on positron emission tomography-computed tomography after allogeneic but not autologous stem-cell transplantation in patients with lymphoma.

PubMed

Ulaner, Gary A; Lilienstein, Joshua; Gönen, Mithat; Maragulia, Jocelyn; Moskowitz, Craig H; Zelenetz, Andrew D

2014-01-01

Determine the clinical significance of [(18)F]fluorodeoxyglucose (FDG)-avid lesions in patients with lymphoma treated with stem-cell transplantation. All patients who underwent stem-cell transplantation for lymphoma at Memorial Sloan-Kettering Cancer Center between January 2005 and December 2009 and had post-transplantation FDG positron emission tomography/computed tomography (PET/CT) examinations were included. PET/CT examinations were evaluated for FDG-avid lesions suggestive of disease. Clinical records, biopsy results, and subsequent imaging examinations were evaluated for malignancy. Two hundred fifty-one patients were identified, 107 with allogeneic and 144 with autologous stem-cell transplantation. Of allogeneic stem-cell transplantation recipients, 50 had FDG-avid lesions suggestive of lymphoma, defined as FDG-avidity greater than liver background. However, only 29 of these 50 demonstrated lymphoma on biopsy, whereas biopsy attempts were benign in the other 21 patients. Sensitivity analysis determined that a 1.5-cm short axis nodal measurement distinguished patients with malignant from nonmalignant biopsies. In 21 of 22 patients with FDG-avid lymph nodes ≤ 1.5 cm, biopsy attempts were benign. In the absence of treatment, these nodes either resolved or were stable on repeat imaging. Disease-free survival of patients with FDG-avid ≤ 1.5 cm lymph nodes was comparable with patients without FDG-avid lesions. In comparison, autologous stem-cell transplantation patients rarely demonstrated FDG-avid lesions suggestive of disease without malignant pathology. Twenty percent (21 of 107) of patients with an allogeneic stem-cell transplantation demonstrated FDG-avid lymph nodes up to 1.5 cm in short axis on PET/CT, which did not represent active lymphoma. After allogeneic stem-cell transplantation of patients with lymphoma, benign FDG-avid ≤ 1.5 cm lymph nodes can mimic malignancy.

Computed tomography arthrography using a radial plane view for the detection of triangular fibrocartilage complex foveal tears.

PubMed

Moritomo, Hisao; Arimitsu, Sayuri; Kubo, Nobuyuki; Masatomi, Takashi; Yukioka, Masao

2015-02-01

To classify triangular fibrocartilage complex (TFCC) foveal lesions on the basis of computed tomography (CT) arthrography using a radial plane view and to correlate the CT arthrography results with surgical findings. We also tested the interobserver and intra-observer reliability of the radial plane view. A total of 33 patients with a suspected TFCC foveal tear who had undergone wrist CT arthrography and subsequent surgical exploration were enrolled. We classified the configurations of TFCC foveal lesions into 5 types on the basis of CT arthrography with the radial plane view in which the image slices rotate clockwise centered on the ulnar styloid process. Sensitivity, specificity, and positive predictive values were calculated for each type of foveal lesion in CT arthrography to detect foveal tears. We determined interobserver and intra-observer agreements using kappa statistics. We also compared accuracies with the radial plane views with those with the coronal plane views. Among the tear types on CT arthrography, type 3, a roundish defect at the fovea, and type 4, a large defect at the overall ulnar insertion, had high specificity and positive predictive value for the detection of foveal tears. Specificity and positive predictive values were 90% and 89% for type 3 and 100% and 100% for type 4, respectively, whereas sensitivity was 35% for type 3 and 22% for type 4. Interobserver and intra-observer agreement was substantial and almost perfect, respectively. The radial plane view identified foveal lesion of each palmar and dorsal radioulnar ligament separately, but accuracy results with the radial plane views were not statistically different from those with the coronal plane views. Computed tomography arthrography with a radial plane view exhibited enhanced specificity and positive predictive value when a type 3 or 4 lesion was identified in the detection of a TFCC foveal tear compared with historical controls. Diagnostic II. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Sinus CT scan

MedlinePlus

CAT scan - sinus; Computed axial tomography scan - sinus; Computed tomography scan - sinus; CT scan - sinus ... Risks for a CT scan includes: Being exposed to radiation Allergic reaction to contrast dye CT scans expose you to more radiation than regular ...

Brain PET scan

MedlinePlus

... tissues are working. Other imaging tests, such as magnetic resonance imaging ( MRI ) and computed tomography ( CT ) scans only reveal ... M, Hellwig S, Kloppel S, Weiller C. Functional neuroimaging: functional magnetic resonance imaging, positron emission tomography, and single-photon emission computed ...

Correlation of quantitative dual-energy computed tomography iodine maps and abdominal computed tomography perfusion measurements: are single-acquisition dual-energy computed tomography iodine maps more than a reduced-dose surrogate of conventional computed tomography perfusion?

PubMed

Stiller, Wolfram; Skornitzke, Stephan; Fritz, Franziska; Klauss, Miriam; Hansen, Jens; Pahn, Gregor; Grenacher, Lars; Kauczor, Hans-Ulrich

2015-10-01

Study objectives were the quantitative evaluation of whether conventional abdominal computed tomography (CT) perfusion measurements mathematically correlate with quantitative single-acquisition dual-energy CT (DECT) iodine concentration maps, the determination of the optimum time of acquisition for achieving maximum correlation, and the estimation of the potential for radiation exposure reduction when replacing conventional CT perfusion by single-acquisition DECT iodine concentration maps. Dual-energy CT perfusion sequences were dynamically acquired over 51 seconds (34 acquisitions every 1.5 seconds) in 24 patients with histologically verified pancreatic carcinoma using dual-source DECT at tube potentials of 80 kVp and 140 kVp. Using software developed in-house, perfusion maps were calculated from 80-kVp image series using the maximum slope model after deformable motion correction. In addition, quantitative iodine maps were calculated for each of the 34 DECT acquisitions per patient. Within a manual segmentation of the pancreas, voxel-by-voxel correlation between the perfusion map and each of the iodine maps was calculated for each patient to determine the optimum time of acquisition topt defined as the acquisition time of the iodine map with the highest correlation coefficient. Subsequently, regions of interest were placed inside the tumor and inside healthy pancreatic tissue, and correlation between mean perfusion values and mean iodine concentrations within these regions of interest at topt was calculated for the patient sample. The mean (SD) topt was 31.7 (5.4) seconds after the start of contrast agent injection. The mean (SD) perfusion values for healthy pancreatic and tumor tissues were 67.8 (26.7) mL per 100 mL/min and 43.7 (32.2) mL per 100 mL/min, respectively. At topt, the mean (SD) iodine concentrations were 2.07 (0.71) mg/mL in healthy pancreatic and 1.69 (0.98) mg/mL in tumor tissue, respectively. Overall, the correlation between perfusion values and iodine concentrations was high (0.77), with correlation of 0.89 in tumor and of 0.56 in healthy pancreatic tissue at topt. Comparing radiation exposure associated with a single DECT acquisition at topt (0.18 mSv) to that of an 80 kVp CT perfusion sequence (2.96 mSv) indicates that an average reduction of Deff by 94% could be achieved by replacing conventional CT perfusion with a single-acquisition DECT iodine concentration map. Quantitative iodine concentration maps obtained with DECT correlate well with conventional abdominal CT perfusion measurements, suggesting that quantitative iodine maps calculated from a single DECT acquisition at an organ-specific and patient-specific optimum time of acquisition might be able to replace conventional abdominal CT perfusion measurements if the time of acquisition is carefully calibrated. This could lead to large reductions of radiation exposure to the patients while offering quantitative perfusion data for diagnosis.

Cone beam computed tomography: basics and applications in dentistry.

PubMed

Venkatesh, Elluru; Elluru, Snehal Venkatesh

2017-01-01

The introduction of cone beam computed tomography (CBCT) devices, changed the way oral and maxillofacial radiology is practiced. CBCT was embraced into the dental settings very rapidly due to its compact size, low cost, low ionizing radiation exposure when compared to medical computed tomography. Alike medical CT, 3 dimensional evaluation of the maxillofacial region with minimal distortion is offered by the CBCT. This article provides an overview of basics of CBCT technology and reviews the specific application of CBCT technology to oral and maxillofacial region with few illustrations.

Microstructure of cotton fibrous assemblies based on computed tomography

NASA Astrophysics Data System (ADS)

Jing, Hui; Yu, Weidong

2017-12-01

This paper describes for the first time the analysis of inner microstructure of cotton fibrous assemblies using computed tomography. Microstructure parameters such as packing density, fractal dimension as well as porosity including open porosity, closed porosity and total porosity are calculated based on 2D data from computed tomography. Values of packing density and fractal dimension are stable in random oriented fibrous assemblies, and there exists a satisfactory approximate linear relationship between them. Moreover, poles analysis indicates that porosity represents the tightness of fibrous assemblies and open poles are main existence.

Progress of projection computed tomography by upgrading of the beamline 37XU of SPring-8

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

Terada, Yasuko, E-mail: yterada@spring8.or.jp; Suzuki, Yoshio; Uesugi, Kentaro

2016-01-28

Beamline 37XU at SPring-8 has been upgraded for nano-focusing applications. The length of the beamline has been extended to 80 m. By utilizing this length, the beamline has advantages for experiments such as X-ray focusing, X-ray microscopic imaging and X-ray computed tomography. Projection computed tomography measurements were carried out at experimental hutch 3 located 80 m from the light source. CT images of a microcapsule have been successfully obtained with a wide X-ray energy range.

The use of iohexol as oral contrast for computed tomography of the abdomen and pelvis.

PubMed

Horton, Karen M; Fishman, Elliot K; Gayler, Bob

2008-01-01

Positive oral contrast agents (high-osmolar iodinated solutions [high-osmolar contrast medium] or barium sulfate suspensions) are used routinely for abdominal computed tomography. However, these agents are not ideal. Patients complain about the taste and, sometimes, refuse to drink the required quantity. Nausea, vomiting, and diarrhea are frequent. In certain clinical indications, either barium suspensions or high-osmolar contrast mediums may be contraindicated. This technical note describes the potential advantages of using low-osmolar iodinated solutions as an oral contrast agent for computed tomography.

Phase-contrast x-ray computed tomography for observing biological specimens and organic materials

NASA Astrophysics Data System (ADS)

Momose, Atsushi; Takeda, Tohoru; Itai, Yuji

1995-02-01

A novel three-dimensional x-ray imaging method has been developed by combining a phase-contrast x-ray imaging technique with x-ray computed tomography. This phase-contrast x-ray computed tomography (PCX-CT) provides sectional images of organic specimens that would produce absorption-contrast x-ray CT images with little contrast. Comparing PCX-CT images of rat cerebellum and cancerous rabbit liver specimens with corresponding absorption-contrast CT images shows that PCX-CT is much more sensitive to the internal structure of organic specimens.

Contours identification of elements in a cone beam computed tomography for investigating maxillary cysts

NASA Astrophysics Data System (ADS)

Chioran, Doina; Nicoarǎ, Adrian; Roşu, Şerban; Cǎrligeriu, Virgil; Ianeş, Emilia

2013-10-01

Digital processing of two-dimensional cone beam computer tomography slicesstarts by identification of the contour of elements within. This paper deals with the collective work of specialists in medicine and applied mathematics in computer science on elaborating and implementation of algorithms in dental 2D imagery.

Neuroanatomy of cranial computed tomography

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

Kretschmann, H.J.; Weinrich, W.

1985-01-01

Based on the fundamental structures visualized by means of computed tomography, the authors present the functional systems which are relevant in neurology by means of axial cross-sections. All drawings were prepared from original preparations by means of a new technique which is similar to the grey values of X-ray CT and nuclear magnetic resonance tomography. A detailed description is given of the topics of neurofunctional lesions.

Frozen Gaussian approximation for 3D seismic tomography

NASA Astrophysics Data System (ADS)

Chai, Lihui; Tong, Ping; Yang, Xu

2018-05-01

Three-dimensional (3D) wave-equation-based seismic tomography is computationally challenging in large scales and high-frequency regime. In this paper, we apply the frozen Gaussian approximation (FGA) method to compute 3D sensitivity kernels and seismic tomography of high-frequency. Rather than standard ray theory used in seismic inversion (e.g. Kirchhoff migration and Gaussian beam migration), FGA is used to compute the 3D high-frequency sensitivity kernels for travel-time or full waveform inversions. Specifically, we reformulate the equations of the forward and adjoint wavefields for the purpose of convenience to apply FGA, and with this reformulation, one can efficiently compute the Green’s functions whose convolutions with source time function produce wavefields needed for the construction of 3D kernels. Moreover, a fast summation method is proposed based on local fast Fourier transform which greatly improves the speed of reconstruction as the last step of FGA algorithm. We apply FGA to both the travel-time adjoint tomography and full waveform inversion (FWI) on synthetic crosswell seismic data with dominant frequencies as high as those of real crosswell data, and confirm again that FWI requires a more sophisticated initial velocity model for the convergence than travel-time adjoint tomography. We also numerically test the accuracy of applying FGA to local earthquake tomography. This study paves the way to directly apply wave-equation-based seismic tomography methods into real data around their dominant frequencies.

Triple primary malignancies of surface osteosarcoma of jaw, myelodysplastic syndrome and colorectal cancer as a second primary cancer detected by PET2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography: A case report.

PubMed

Maruyama, Nobuyuki; Nishihara, Kazuhide; Nakasone, Toshiyuki; Saio, Masanao; Maruyama, Tessho; Tedokon, Iori; Ohira, Tetsuya; Nimura, Fumikazu; Matayoshi, Akira; Karube, Ken-Nosuke; Yoshimi, Naoki; Arasaki, Akira

2018-06-01

Second primary malignancy (SPM) is a severe issue for cancer survivors, particularly for osteosarcoma (OS) survivors. To date, the associations between subsequent SPM and OS have been well reported. Hematogenic and solid malignancies tend to occur following OS treatment. Reportedly, 2-[ 18 F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is mainly used in OS patients for initial cancer staging, to evaluate the response of neoadjuvant chemotherapy, and when recurrence or metastasis is clinically suspected. The present case report describes a 70-year-old man diagnosed with three primary malignancies: jaw OS, myelodysplastic syndrome and colorectal adenocarcinoma. To the best of our knowledge, this combination of malignancies has not been reported previously. Until now, there is no specific protocol of postoperative FDG-PET for OS patients. Few studies have described OS follow-up methods; therefore, there is no consensus on proper follow-up methods. In the present case report, the colorectal early-stage SPM was observed, without any symptoms, by FDG-PET/computed tomography. To avoid overlooking solid SPMs, it is suggested that FDG-PET should be performed in the long-term follow-up of OS patients.

Pediatric minor head trauma: do cranial CT scans change the therapeutic approach?

PubMed

Andrade, Felipe P; Montoro, Roberto; Oliveira, Renan; Loures, Gabriela; Flessak, Luana; Gross, Roberta; Donnabella, Camille; Puchnick, Andrea; Suzuki, Lisa; Regacini, Rodrigo

2016-10-01

1) To verify clinical signs correlated with appropriate cranial computed tomography scan indications and changes in the therapeutic approach in pediatric minor head trauma scenarios. 2) To estimate the radiation exposure of computed tomography scans with low dose protocols in the context of trauma and the additional associated risk. Investigators reviewed the medical records of all children with minor head trauma, which was defined as a Glasgow coma scale ≥13 at the time of admission to the emergency room, who underwent computed tomography scans during the years of 2013 and 2014. A change in the therapeutic approach was defined as a neurosurgical intervention performed within 30 days, hospitalization, >12 hours of observation, or neuro-specialist evaluation. Of the 1006 children evaluated, 101 showed some abnormality on head computed tomography scans, including 49 who were hospitalized, 16 who remained under observation and 36 who were dismissed. No patient underwent neurosurgery. No statistically significant relationship was observed between patient age, time between trauma and admission, or signs/symptoms related to trauma and abnormal imaging results. A statistically significant relationship between abnormal image results and a fall higher than 1.0 meter was observed (p=0.044). The mean effective dose was 2.0 mSv (0.1 to 6.8 mSv), corresponding to an estimated additional cancer risk of 0.05%. A computed tomography scan after minor head injury in pediatric patients did not show clinically relevant abnormalities that could lead to neurosurgical indications. Patients who fell more than 1.0 m were more likely to have changes in imaging tests, although these changes did not require neurosurgical intervention; therefore, the use of computed tomography scans may be questioned in this group. The results support the trend of more careful indications for cranial computed tomography scans for children with minor head trauma.

Computed Tomography Perfusion, Magnetic Resonance Imaging, and Histopathological Findings After Laparoscopic Renal Cryoablation: An In Vivo Pig Model.

PubMed

Nielsen, Tommy Kjærgaard; Østraat, Øyvind; Graumann, Ole; Pedersen, Bodil Ginnerup; Andersen, Gratien; Høyer, Søren; Borre, Michael

2017-08-01

The present study investigates how computed tomography perfusion scans and magnetic resonance imaging correlates with the histopathological alterations in renal tissue after cryoablation. A total of 15 pigs were subjected to laparoscopic-assisted cryoablation on both kidneys. After intervention, each animal was randomized to a postoperative follow-up period of 1, 2, or 4 weeks, after which computed tomography perfusion and magnetic resonance imaging scans were performed. Immediately after imaging, open bilateral nephrectomy was performed allowing for histopathological examination of the cryolesions. On computed tomography perfusion and magnetic resonance imaging examinations, rim enhancement was observed in the transition zone of the cryolesion 1week after laparoscopic-assisted cryoablation. This rim enhancement was found to subside after 2 and 4 weeks of follow-up, which was consistent with the microscopic examinations revealing of fibrotic scar tissue formation in the peripheral zone of the cryolesion. On T2 magnetic resonance imaging sequences, a thin hypointense rim surrounded the cryolesion, separating it from the adjacent renal parenchyma. Microscopic examinations revealed hemorrhage and later hemosiderin located in the peripheral zone. No nodular or diffuse contrast enhancement was found in the central zone of the cryolesions at any follow-up stage on neither computed tomography perfusion nor magnetic resonance imaging. On microscopic examinations, the central zone was found to consist of coagulative necrosis 1 week after laparoscopic-assisted cryoablation, which was partially replaced by fibrotic scar tissue 4 weeks following laparoscopic-assisted cryoablation. Both computed tomography perfusion and magnetic resonance imaging found the renal collecting system to be involved at all 3 stages of follow-up, but on microscopic examination, the urothelium was found to be intact in all cases. In conclusion, cryoablation effectively destroyed renal parenchyma, leaving the urothelium intact. Both computed tomography perfusion and magnetic resonance imaging reflect the microscopic findings but with some differences, especially regarding the peripheral zone. Magnetic resonance imaging seems an attractive modality for early postoperative follow-up.

Validation of a computational knee joint model using an alignment method for the knee laxity test and computed tomography.

PubMed

Kang, Kyoung-Tak; Kim, Sung-Hwan; Son, Juhyun; Lee, Young Han; Koh, Yong-Gon

2017-01-01

Computational models have been identified as efficient techniques in the clinical decision-making process. However, computational model was validated using published data in most previous studies, and the kinematic validation of such models still remains a challenge. Recently, studies using medical imaging have provided a more accurate visualization of knee joint kinematics. The purpose of the present study was to perform kinematic validation for the subject-specific computational knee joint model by comparison with subject's medical imaging under identical laxity condition. The laxity test was applied to the anterior-posterior drawer under 90° flexion and the varus-valgus under 20° flexion with a series of stress radiographs, a Telos device, and computed tomography. The loading condition in the computational subject-specific knee joint model was identical to the laxity test condition in the medical image. Our computational model showed knee laxity kinematic trends that were consistent with the computed tomography images, except for negligible differences because of the indirect application of the subject's in vivo material properties. Medical imaging based on computed tomography with the laxity test allowed us to measure not only the precise translation but also the rotation of the knee joint. This methodology will be beneficial in the validation of laxity tests for subject- or patient-specific computational models.

Efficient visibility-driven medical image visualisation via adaptive binned visibility histogram.

PubMed

Jung, Younhyun; Kim, Jinman; Kumar, Ashnil; Feng, David Dagan; Fulham, Michael

2016-07-01

'Visibility' is a fundamental optical property that represents the observable, by users, proportion of the voxels in a volume during interactive volume rendering. The manipulation of this 'visibility' improves the volume rendering processes; for instance by ensuring the visibility of regions of interest (ROIs) or by guiding the identification of an optimal rendering view-point. The construction of visibility histograms (VHs), which represent the distribution of all the visibility of all voxels in the rendered volume, enables users to explore the volume with real-time feedback about occlusion patterns among spatially related structures during volume rendering manipulations. Volume rendered medical images have been a primary beneficiary of VH given the need to ensure that specific ROIs are visible relative to the surrounding structures, e.g. the visualisation of tumours that may otherwise be occluded by neighbouring structures. VH construction and its subsequent manipulations, however, are computationally expensive due to the histogram binning of the visibilities. This limits the real-time application of VH to medical images that have large intensity ranges and volume dimensions and require a large number of histogram bins. In this study, we introduce an efficient adaptive binned visibility histogram (AB-VH) in which a smaller number of histogram bins are used to represent the visibility distribution of the full VH. We adaptively bin medical images by using a cluster analysis algorithm that groups the voxels according to their intensity similarities into a smaller subset of bins while preserving the distribution of the intensity range of the original images. We increase efficiency by exploiting the parallel computation and multiple render targets (MRT) extension of the modern graphical processing units (GPUs) and this enables efficient computation of the histogram. We show the application of our method to single-modality computed tomography (CT), magnetic resonance (MR) imaging and multi-modality positron emission tomography-CT (PET-CT). In our experiments, the AB-VH markedly improved the computational efficiency for the VH construction and thus improved the subsequent VH-driven volume manipulations. This efficiency was achieved without major degradation in the VH visually and numerical differences between the AB-VH and its full-bin counterpart. We applied several variants of the K-means clustering algorithm with varying Ks (the number of clusters) and found that higher values of K resulted in better performance at a lower computational gain. The AB-VH also had an improved performance when compared to the conventional method of down-sampling of the histogram bins (equal binning) for volume rendering visualisation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Computed tomography or rhinoscopy as the first-line procedure for suspected nasal tumor: a pilot study.

PubMed

Finck, Marlène; Ponce, Frédérique; Guilbaud, Laurent; Chervier, Cindy; Floch, Franck; Cadoré, Jean-Luc; Chuzel, Thomas; Hugonnard, Marine

2015-02-01

There are no evidence-based guidelines as to whether computed tomography (CT) or endoscopy should be selected as the first-line procedure when a nasal tumor is suspected in a dog or a cat and only one examination can be performed. Computed tomography and rhinoscopic features of 17 dogs and 5 cats with a histopathologically or cytologically confirmed nasal tumor were retrospectively reviewed. The level of suspicion for nasal neoplasia after CT and/or rhinoscopy was compared to the definitive diagnosis. Twelve animals underwent CT, 14 underwent rhinoscopy, and 4 both examinations. Of the 12 CT examinations performed, 11 (92%) resulted in the conclusion that a nasal tumor was the most likely diagnosis compared with 9/14 (64%) for rhinoscopies. Computed tomography appeared to be more reliable than rhinoscopy for detecting nasal tumors and should therefore be considered as the first-line procedure.

Computed tomography or rhinoscopy as the first-line procedure for suspected nasal tumor: A pilot study

PubMed Central

Finck, Marlène; Ponce, Frédérique; Guilbaud, Laurent; Chervier, Cindy; Floch, Franck; Cadoré, Jean-Luc; Chuzel, Thomas; Hugonnard, Marine

2015-01-01

There are no evidence-based guidelines as to whether computed tomography (CT) or endoscopy should be selected as the first-line procedure when a nasal tumor is suspected in a dog or a cat and only one examination can be performed. Computed tomography and rhinoscopic features of 17 dogs and 5 cats with a histopathologically or cytologically confirmed nasal tumor were retrospectively reviewed. The level of suspicion for nasal neoplasia after CT and/or rhinoscopy was compared to the definitive diagnosis. Twelve animals underwent CT, 14 underwent rhinoscopy, and 4 both examinations. Of the 12 CT examinations performed, 11 (92%) resulted in the conclusion that a nasal tumor was the most likely diagnosis compared with 9/14 (64%) for rhinoscopies. Computed tomography appeared to be more reliable than rhinoscopy for detecting nasal tumors and should therefore be considered as the first-line procedure. PMID:25694669

Review of cardiovascular imaging in The Journal of Nuclear Cardiology in 2014: Part 1 of 2: Positron emission tomography, computed tomography, and neuronal imaging.

PubMed

AlJaroudi, Wael A; Hage, Fadi G

2015-06-01

The year 2014 has been an exciting year for the cardiovascular imaging community with significant advances in the realm of nuclear and multimodality cardiac imaging. In this new feature of the Journal of Nuclear Cardiology, we will summarize some of the breakthroughs that were published in the Journal in 2014 in 2 sister articles. This first article will concentrate on publications dealing with cardiac positron emission tomography (PET), computed tomography (CT), and neuronal imaging.

Trends in micro- and nanoComputed Tomography 2008-2010

NASA Astrophysics Data System (ADS)

Stock, S. R.

2010-09-01

Trends in micro- and nanoComputed Tomography (CT) from January 2008 through July 2010 are the subject of this brief report which takes up where a previous report in Developments in X-ray Tomography VI (2008) concluded. First, the number of systems operating world-wide is estimated. The main focus is on what searches of three citation indices (Web of Science, Compendex and PubMed) reveal about the field of micro- and nanoCT. Given research-fielddependent and disparate terminology used by investigators, searches were on "microtomography", "microCT" and "synchrotron tomography".

A tomographic technique for aerodynamics at transonic speeds

NASA Technical Reports Server (NTRS)

Lee, G.

1985-01-01

Computer aided tomography (CAT) provides a means of noninvasively measuring the air density distribution around an aerodynamic model. This technique is global in that a large portion of the flow field can be measured. A test of the applicability of CAT to transonic velocities was studied. A hemispherical-nose cylinder afterbody model was tested at a Mach number of 0.8 with a new laser holographic interferometer at the 2- by 2-Foot Transonic Wind Tunnel. Holograms of the flow field were taken and were reconstructed into interferograms. The fringe distribution (a measure of the local densities) was digitized for subsequent data reduction. A computer program based on the Fourier-transform technique was developed to convert the fringe distribution into three-dimensional densities around the model. Theoretical aerodynamic densities were calculated for evaluating and assessing the accuracy of the data obtained from the tomographic method.

Integrating Dimension Reduction and Out-of-Sample Extension in Automated Classification of Ex Vivo Human Patellar Cartilage on Phase Contrast X-Ray Computed Tomography

PubMed Central

Nagarajan, Mahesh B.; Coan, Paola; Huber, Markus B.; Diemoz, Paul C.; Wismüller, Axel

2015-01-01

Phase contrast X-ray computed tomography (PCI-CT) has been demonstrated as a novel imaging technique that can visualize human cartilage with high spatial resolution and soft tissue contrast. Different textural approaches have been previously investigated for characterizing chondrocyte organization on PCI-CT to enable classification of healthy and osteoarthritic cartilage. However, the large size of feature sets extracted in such studies motivates an investigation into algorithmic feature reduction for computing efficient feature representations without compromising their discriminatory power. For this purpose, geometrical feature sets derived from the scaling index method (SIM) were extracted from 1392 volumes of interest (VOI) annotated on PCI-CT images of ex vivo human patellar cartilage specimens. The extracted feature sets were subject to linear and non-linear dimension reduction techniques as well as feature selection based on evaluation of mutual information criteria. The reduced feature set was subsequently used in a machine learning task with support vector regression to classify VOIs as healthy or osteoarthritic; classification performance was evaluated using the area under the receiver-operating characteristic (ROC) curve (AUC). Our results show that the classification performance achieved by 9-D SIM-derived geometric feature sets (AUC: 0.96 ± 0.02) can be maintained with 2-D representations computed from both dimension reduction and feature selection (AUC values as high as 0.97 ± 0.02). Thus, such feature reduction techniques can offer a high degree of compaction to large feature sets extracted from PCI-CT images while maintaining their ability to characterize the underlying chondrocyte patterns. PMID:25710875

[Measurement of intracranial hematoma volume by personal computer].

PubMed

DU, Wanping; Tan, Lihua; Zhai, Ning; Zhou, Shunke; Wang, Rui; Xue, Gongshi; Xiao, An

2011-01-01

To explore the method for intracranial hematoma volume measurement by the personal computer. Forty cases of various intracranial hematomas were measured by the computer tomography with quantitative software and personal computer with Photoshop CS3 software, respectively. the data from the 2 methods were analyzed and compared. There was no difference between the data from the computer tomography and the personal computer (P>0.05). The personal computer with Photoshop CS3 software can measure the volume of various intracranial hematomas precisely, rapidly and simply. It should be recommended in the clinical medicolegal identification.

Computed Tomography of the Musculoskeletal System.

PubMed

Ballegeer, Elizabeth A

2016-05-01

Computed tomography (CT) has specific uses in veterinary species' appendicular musculoskeletal system. Parameters for acquisition of images, interpretation limitations, as well as published information regarding its use in small animals is reviewed. Copyright © 2016 Elsevier Inc. All rights reserved.

Intraoperative 3-Dimensional Computed Tomography and Navigation in Foot and Ankle Surgery.

PubMed

Chowdhary, Ashwin; Drittenbass, Lisca; Dubois-Ferrière, Victor; Stern, Richard; Assal, Mathieu

2016-09-01

Computer-assisted orthopedic surgery has developed dramatically during the past 2 decades. This article describes the use of intraoperative 3-dimensional computed tomography and navigation in foot and ankle surgery. Traditional imaging based on serial radiography or C-arm-based fluoroscopy does not provide simultaneous real-time 3-dimensional imaging, and thus leads to suboptimal visualization and guidance. Three-dimensional computed tomography allows for accurate intraoperative visualization of the position of bones and/or navigation implants. Such imaging and navigation helps to further reduce intraoperative complications, leads to improved surgical outcomes, and may become the gold standard in foot and ankle surgery. [Orthopedics.2016; 39(5):e1005-e1010.]. Copyright 2016, SLACK Incorporated.

Domain identification in impedance computed tomography by spline collocation method

NASA Technical Reports Server (NTRS)

Kojima, Fumio

1990-01-01

A method for estimating an unknown domain in elliptic boundary value problems is considered. The problem is formulated as an inverse problem of integral equations of the second kind. A computational method is developed using a splice collocation scheme. The results can be applied to the inverse problem of impedance computed tomography (ICT) for image reconstruction.

Fast automatic segmentation of anatomical structures in x-ray computed tomography images to improve fluorescence molecular tomography reconstruction.

PubMed

Freyer, Marcus; Ale, Angelique; Schulz, Ralf B; Zientkowska, Marta; Ntziachristos, Vasilis; Englmeier, Karl-Hans

2010-01-01

The recent development of hybrid imaging scanners that integrate fluorescence molecular tomography (FMT) and x-ray computed tomography (XCT) allows the utilization of x-ray information as image priors for improving optical tomography reconstruction. To fully capitalize on this capacity, we consider a framework for the automatic and fast detection of different anatomic structures in murine XCT images. To accurately differentiate between different structures such as bone, lung, and heart, a combination of image processing steps including thresholding, seed growing, and signal detection are found to offer optimal segmentation performance. The algorithm and its utilization in an inverse FMT scheme that uses priors is demonstrated on mouse images.

Clinical applications of cone beam computed tomography in endodontics: A comprehensive review.

PubMed

Cohenca, Nestor; Shemesh, Hagay

2015-09-01

The use of cone beam computed tomography (CBCT) in endodontics has been extensively reported in the literature. Compared with the traditional spiral computed tomography, limited field of view (FOV) CBCT results in a fraction of the effective absorbed dose of radiation. The purpose of this manuscript is to review the application and advantages associated with advanced endodontic problems and complications, while reducing radiation exposure during complex endodontic procedures. The benefits of the added diagnostic information provided by intraoperative CBCT images in select cases justify the risk associated with the limited level of radiation exposure.

Dry coupling for whole-body small-animal photoacoustic computed tomography

NASA Astrophysics Data System (ADS)

Yeh, Chenghung; Li, Lei; Zhu, Liren; Xia, Jun; Li, Chiye; Chen, Wanyi; Garcia-Uribe, Alejandro; Maslov, Konstantin I.; Wang, Lihong V.

2017-04-01

We have enhanced photoacoustic computed tomography with dry acoustic coupling that eliminates water immersion anxiety and wrinkling of the animal and facilitates incorporating complementary modalities and procedures. The dry acoustic coupler is made of a tubular elastic membrane enclosed by a closed transparent water tank. The tubular membrane ensures water-free contact with the animal, and the closed water tank allows pressurization for animal stabilization. The dry coupler was tested using a whole-body small-animal ring-shaped photoacoustic computed tomography system. Dry coupling was found to provide image quality comparable to that of conventional water coupling.

Linear-array based full-view high-resolution photoacoustic computed tomography of whole mouse brain functions in vivo

NASA Astrophysics Data System (ADS)

Li, Lei; Zhang, Pengfei; Wang, Lihong V.

2018-02-01

Photoacoustic computed tomography (PACT) is a non-invasive imaging technique offering high contrast, high resolution, and deep penetration in biological tissues. We report a photoacoustic computed tomography (PACT) system equipped with a high frequency linear array for anatomical and functional imaging of the mouse whole brain. The linear array was rotationally scanned in the coronal plane to achieve the full-view coverage. We investigated spontaneous neural activities in the deep brain by monitoring the hemodynamics and observed strong interhemispherical correlations between contralateral regions, both in the cortical layer and in the deep regions.

Broadband Terahertz Computed Tomography Using a 5k-pixel Real-time THz Camera

NASA Astrophysics Data System (ADS)

Trichopoulos, Georgios C.; Sertel, Kubilay

2015-07-01

We present a novel THz computed tomography system that enables fast 3-dimensional imaging and spectroscopy in the 0.6-1.2 THz band. The system is based on a new real-time broadband THz camera that enables rapid acquisition of multiple cross-sectional images required in computed tomography. Tomographic reconstruction is achieved using digital images from the densely-packed large-format (80×64) focal plane array sensor located behind a hyper-hemispherical silicon lens. Each pixel of the sensor array consists of an 85 μm × 92 μm lithographically fabricated wideband dual-slot antenna, monolithically integrated with an ultra-fast diode tuned to operate in the 0.6-1.2 THz regime. Concurrently, optimum impedance matching was implemented for maximum pixel sensitivity, enabling 5 frames-per-second image acquisition speed. As such, the THz computed tomography system generates diffraction-limited resolution cross-section images as well as the three-dimensional models of various opaque and partially transparent objects. As an example, an over-the-counter vitamin supplement pill is imaged and its material composition is reconstructed. The new THz camera enables, for the first time, a practical application of THz computed tomography for non-destructive evaluation and biomedical imaging.

[Contribution of X-ray computed tomography in the evaluation of kidney performance].

PubMed

Lemoine, Sandrine; Rognant, Nicolas; Collet-Benzaquen, Diane; Juillard, Laurent

2012-07-01

X-ray computer assisted tomography scanner is an imaging method based on the use of X-ray attenuation in tissue. This attenuation is proportional to the density of the tissue (without or after contrast media injection) in each pixel image of the image. Spiral scanner, the electron beam computed tomography (EBCT) scanner and multidetector computed tomography scanner allow renal anatomical measurements, such as cortical and medullary volume, but also the measurement of renal functional parameters, such as regional renal perfusion, renal blood flow and glomerular filtration rate. These functional parameters are extracted from the modeling of the kinetics of the contrast media concentration in the vascular space and the renal tissue, using two main mathematical models (the gamma variate model and the Patlak model). Renal functional imaging allows measuring quantitative parameters on each kidney separately, in a non-invasive manner, providing significant opportunities in nephrology, both for experimental and clinical studies. However, this method uses contrast media that may alter renal function, thus limiting its use in patients with chronic renal failure. Moreover, the increase irradiation delivered to the patient with multi detector computed tomography (MDCT) should be considered. Copyright © 2011 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.

A new surgical template with a handpiece positioner for use during flapless placement of four dental implants to retain a mandibular overdenture.

PubMed

Elsyad, Moustafa Abdou

2012-10-01

This article describes the fabrication of a new and inexpensive surgical template from a radiographic template for flapless placement of dental implants to retain a mandibular overdenture. A radiographic template with radiopaque metal plate markers is constructed and used as a guide for achieving three-dimensional evaluation of bone using computed tomography (CT). The potential position and angulation of the implants are measured relative to the metal plates using the CT data. The radiographic template is converted into a surgical template by attaching rigid metal rods that guide the handpiece precisely during subsequent drilling procedures. © 2012 by the American College of Prosthodontists.

PEComa of the mesentery coexisting with colon cancer: a case report.

PubMed

Wejman, Jarosław; Nowak, Krzysztof; Gielniewska, Lena; Komorowska, Magdalena; Dąbrowski, Wojciech

2015-04-18

Perivascular epithelioid cell tumor (PEComa) is a rare entity originating from mesenchymal tissue, which stains for both melanocytic and smooth muscle markers. We would like to present an unusual case of the PEComa of the mesentery which was unexpected discovery in a female patient with colonic adenocarcinoma. The tumour was revealed on the computer tomography and then resected during surgery, with subsequent chemotherapy for the colon adenocarcinoma. Furthermore we would like to discuss PEComa biology, emphasizing histological criteria of malignancy, possible treatment options and differential diagnosis which is mostly based on immunohistochemistry. Virtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1809062291157051 .

Methicillin-resistant Staphylococcus aureus hepatic abscess in a patient with sickle-cell disease.

PubMed

Mancao, M; Estrada, B; Wilson, F; Figarola, M; Wesenberg, R

2007-12-01

We report a case of a 16-year-old female patient with sickle-cell disease with a liver abscess secondary to methicillin-resistant Staphylococcus aureus (MRSA). She had initially presented with jaundice and abdominal pain and subsequently underwent endoscopic retrograde cholangio-pancreaticography followed by laparoscopic cholecystectomy for removal of gallstones. However, post-cholecystectomy she presented with generalized abdominal pain and computed tomography scan of the abdomen revealed a liver abscess. A pigtail catheter was inserted into the abscess and culture of the aspirate yielded MRSA (susceptibility pattern of the organism was compatible with community-acquired MRSA). She was treated with intravenous clindamycin for 6 weeks with complete resolution of the abscess.

Inter- and intraobserver reliability of the vertebral, local and segmental kyphosis in 120 traumatic lumbar and thoracic burst fractures: evaluation in lateral X-rays and sagittal computed tomographies

PubMed Central

Brunner, Alexander; Gühring, Markus; Schmälzle, Traude; Weise, Kuno; Badke, Andreas

2009-01-01

Evaluation of the kyphosis angle in thoracic and lumbar burst fractures is often used to indicate surgical procedures. The kyphosis angle could be measured as vertebral, segmental and local kyphosis according to the method of Cobb. The vertebral, segmental and local kyphosis according to the method of Cobb were measured at 120 lateral X-rays and sagittal computed tomographies of 60 thoracic and 60 lumbar burst fractures by 3 independent observers on 2 separate occasions. Osteoporotic fractures were excluded. The intra- and interobserver reliability of these angles in X-ray and computed tomogram, using the intra class correlation coefficient (ICC) were evaluated. Highest reproducibility showed the segmental kyphosis followed by the vertebral kyphosis. For thoracic fractures segmental kyphosis shows in X-ray “excellent” inter- and intraobserver reliabilities (ICC 0.826, 0.802) and for lumbar fractures “good” to “excellent” inter- and intraobserver reliabilities (ICC = 0.790, 0.803). In computed tomography, the segmental kyphosis showed “excellent” inter- and intraobserver reliabilities (ICC = 0.824, 0.801) for thoracic and “excellent” inter- and intraobserver reliabilities (ICC = 0.874, 0.835) for the lumbar fractures. Regarding both diagnostic work ups (X-ray and computed tomography), significant differences were evaluated in interobserver reliabilities for vertebral kyphosis measured in lumbar fracture X-rays (p = 0.035) and interobserver reliabilities for local kyphosis, measured in thoracic fracture X-rays (p = 0.010). Regarding both fracture localizations (thoracic and lumbar fractures), significant differences could only be evaluated in interobserver reliabilities for the local kyphosis measured in computed tomographies (p = 0.045) and in intraobserver reliabilities for the vertebral kyphosis measured in X-rays (p = 0.024). “Good” to “excellent” inter- and intraobserver reliabilities for vertebral, segmental and local kyphosis in X-ray make these angles to a helpful tool, indicating surgical procedures. For the practical use in lateral X-ray, we emphasize the determination of the segmental kyphosis, because of the highest reproducibility of this angle. “Good” to “excellent” inter- and intraobserver reliabilities for these three angles could also be evaluated in computed tomographies. Therefore, also in computed tomography, the use of these three angles seems to be generally possible. For a direct correlation of the results in lateral X-ray and in computed tomography, further studies should be needed. PMID:19953277

Dipyridamole stress myocardial perfusion by computed tomography in patients with left bundle branch block.

PubMed

Cabeda, Estêvan Vieira; Falcão, Andréa Maria Gomes; Soares, José; Rochitte, Carlos Eduardo; Nomura, César Higa; Ávila, Luiz Francisco Rodrigues; Parga, José Rodrigues

2015-12-01

Functional tests have limited accuracy for identifying myocardial ischemia in patients with left bundle branch block (LBBB). To assess the diagnostic accuracy of dipyridamole-stress myocardial computed tomography perfusion (CTP) by 320-detector CT in patients with LBBB using invasive quantitative coronary angiography (QCA) (stenosis ≥ 70%) as reference; to investigate the advantage of adding CTP to coronary computed tomography angiography (CTA) and compare the results with those of single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy. Thirty patients with LBBB who had undergone SPECT for the investigation of coronary artery disease were referred for stress tomography. Independent examiners performed per-patient and per-coronary territory assessments. All patients gave written informed consent to participate in the study that was approved by the institution's ethics committee. The patients' mean age was 62 ± 10 years. The mean dose of radiation for the tomography protocol was 9.3 ± 4.6 mSv. With regard to CTP, the per-patient values for sensitivity, specificity, positive and negative predictive values, and accuracy were 86%, 81%, 80%, 87%, and 83%, respectively (p = 0.001). The per-territory values were 63%, 86%, 65%, 84%, and 79%, respectively (p < 0.001). In both analyses, the addition of CTP to CTA achieved higher diagnostic accuracy for detecting myocardial ischemia than SPECT (p < 0.001). The use of the stress tomography protocol is feasible and has good diagnostic accuracy for assessing myocardial ischemia in patients with LBBB.

Role of positron emission tomography/computed tomography in breast cancer.

PubMed

Bourgeois, Austin C; Warren, Lance A; Chang, Ted T; Embry, Scott; Hudson, Kathleen; Bradley, Yong C

2013-09-01

Although positron emission tomography (PET) imaging may not be used in the diagnosis of breast cancer, the use of PET/computed tomography is imperative in all aspects of breast cancer staging, treatment, and follow-up. PET will continue to be relevant in personalized medicine because accurate tumor status will be even more critical during and after the transition from a generic metabolic agent to receptor imaging. Positron emission mammography is an imaging proposition that may have benefits in lower doses, but its use is limited without new radiopharmaceuticals. Copyright © 2013 Elsevier Inc. All rights reserved.

Transurethral Ultrasound Diffraction Tomography

DTIC Science & Technology

2007-03-01

the covariance matrix was derived. The covariance reduced to that of the X- ray CT under the assumptions of linear operator and real data.[5] The...the covariance matrix in the linear x- ray computed tomography is a special case of the inverse scattering matrix derived in this paper. The matrix was...is derived in Sec. IV, and its relation to that of the linear x- ray computed tomography appears in Sec. V. In Sec. VI, the inverse scattering

APPLICATION OF COMPUTER AIDED TOMOGRAPHY (CAT) TO THE STUDY OF MARINE BENTIC COMMUNITIES

EPA Science Inventory

Sediment cores were imaged using a Computer-Aided Tomography (CT) scanner at Massachusetts General Hospital, Boston, Massachusetts, United States. Procedures were developed, using the attenuation of X-rays, to differentiate between sediment and the water contained in macrobenthic...

How to interpret computed tomography of the lumbar spine

PubMed Central

Mobasheri, R; Das, T; Vaidya, S; Mallik, S; El-Hussainy, M; Casey, A

2014-01-01

Computed tomography (CT) of the spine has remained an important tool in the investigation of spinal pathology. This article helps to explain the basics of CT of the lumbar spine to allow the clinician better use of this diagnostic tool. PMID:25245727

Clinical and computed tomography features of secondary renal hyperparathyroidism

PubMed Central

Vanbrugghe, Benoît; Blond, Laurent; Carioto, Lisa; Carmel, Eric Norman; Nadeau, Marie-Eve

2011-01-01

An atypical case of secondary renal hyperparathyroidism was diagnosed in a 9-year-old miniature schnauzer after a skull computed tomography (CT) showed the presence of 2 bilateral and symmetrical soft tissue maxillary masses, and osteopenia of the skull. PMID:21532826

Immediate implant placement: the fate of the buccal crest. A retrospective cone beam computed tomography study.

PubMed

Groenendijk, E; Staas, T A; Graauwmans, F E J; Bronkhorst, E; Verhamme, L; Maal, T; Meijer, G J

2017-12-01

This retrospective study aimed to analyse the fate of the buccal crest after immediate implant placement (IIP) through the use of cone beam computed tomography (CBCT). In 16 consecutive patients, an implant was placed in a more palatal position after extraction, thereby creating a gap of at least 2mm between the implant and the buccal crest. Subsequently, this gap was filled with a bone substitute. Preoperatively, immediate postoperatively, and late postoperatively, a CBCT was made to measure the thickness of the buccal crest. After application of the bone substitute, the buccal crest increased in thickness from 0.9mm to 2.4mm (mean). At a mean of 103 weeks after IIP, late postoperative CBCT scans showed that the thickness of the buccal crest was compacted to 1.8mm. In the same period, the height of the buccal crest increased by 1.6mm (mean) to, on average, 1.2mm above the implant shoulder. The aesthetic outcome was analysed using the White and Pink Esthetic Score (WES and PES). Both scored high: 8.4 and 11.8, respectively. Within the limitations of this study, the results of this IIP protocol are promising. Long-term prospective research on this topic on a large number of patients is necessary. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

[A Case Strongly Suspected of Being Pulmonary Toxocariasis Showing Multiple Pulmonary Nodules with a Disappearing and Reappearing Halo Sign].

PubMed

Takakura, Akira; Harada, Shinya; Katono, Ken; Igawa, Satoshi; Katagiri, Masato; Yanase, Nobuo; Masuda, Noriyuki

2015-03-01

We report herein on a case strongly suspected of being pulmonary toxocariasis. A 22-year-old Indonesian man referred to our hospital presented with abnormal chest shadows upon medical examination. He had no symptoms. He did not have any pets nor did he eat raw beef or chicken. Hematological examination revealed eosinophilia and elevation of IgE. Chest computed tomography revealed 3 pulmonary nodules with the halo sign. We suspected a parasite infection and performed antiparasite antibody testing. Ascaris suum was slightly positive on the screening test. As specific antibody against the larval excretory-secretory products of Toxocara canis, measured at the National Institute of Infectious Diseases, was positive (level 3 up to 8). Subsequently, the abnormal chest shadows disappeared. However, two months later, 2 pulmonary nodules with the halo sign reappeared in other places. Diagnostic therapy with albendazole was performed for 8 weeks. Mild hepatic impairment emerged during therapy, but it was within the allowed range. Thereafter, the results improved for the imaging findings, eosinophilia, serum IgE level, and specific antibody. The antibody level became negative two months after the treatment had ended. We should consider toxocariasis in the differential diagnosis of migratory nodular shadows with the halo sign on chest computed tomography, and immunoserological testing is useful for the diagnosis.

Volumetric characterization of human patellar cartilage matrix on phase contrast x-ray computed tomography

NASA Astrophysics Data System (ADS)

Abidin, Anas Z.; Nagarajan, Mahesh B.; Checefsky, Walter A.; Coan, Paola; Diemoz, Paul C.; Hobbs, Susan K.; Huber, Markus B.; Wismüller, Axel

2015-03-01

Phase contrast X-ray computed tomography (PCI-CT) has recently emerged as a novel imaging technique that allows visualization of cartilage soft tissue, subsequent examination of chondrocyte patterns, and their correlation to osteoarthritis. Previous studies have shown that 2D texture features are effective at distinguishing between healthy and osteoarthritic regions of interest annotated in the radial zone of cartilage matrix on PCI-CT images. In this study, we further extend the texture analysis to 3D and investigate the ability of volumetric texture features at characterizing chondrocyte patterns in the cartilage matrix for purposes of classification. Here, we extracted volumetric texture features derived from Minkowski Functionals and gray-level co-occurrence matrices (GLCM) from 496 volumes of interest (VOI) annotated on PCI-CT images of human patellar cartilage specimens. The extracted features were then used in a machine-learning task involving support vector regression to classify ROIs as healthy or osteoarthritic. Classification performance was evaluated using the area under the receiver operating characteristic (ROC) curve (AUC). The best classification performance was observed with GLCM features correlation (AUC = 0.83 +/- 0.06) and homogeneity (AUC = 0.82 +/- 0.07), which significantly outperformed all Minkowski Functionals (p < 0.05). These results suggest that such quantitative analysis of chondrocyte patterns in human patellar cartilage matrix involving GLCM-derived statistical features can distinguish between healthy and osteoarthritic tissue with high accuracy.

Real-time computed tomography dosimetry during ultrasound-guided brachytherapy for prostate cancer.

PubMed

Kaplan, Irving D; Meskell, Paul; Oldenburg, Nicklas E; Saltzman, Brian; Kearney, Gary P; Holupka, Edward J

2006-01-01

Ultrasound-guided implantation of permanent radioactive seeds is a treatment option for localized prostate cancer. Several techniques have been described for the optimal placement of the seeds in the prostate during this procedure. Postimplantation dosimetric calculations are performed after the implant. Areas of underdosing can only be corrected with either an external beam boost or by performing a second implant. We demonstrate the feasibility of performing computed tomography (CT)-based postplanning during the ultrasound-guided implant and subsequently correcting for underdosed areas. Ultrasound-guided brachytherapy is performed on a modified CT table with general anesthesia. The postplanning CT scan is performed after the implant, while the patient is still under anesthesia. Additional seeds are implanted into "cold spots," and the resultant dosimetry confirmed with CT. Intraoperative postplanning was successfully performed. Dose-volume histograms demonstrated adequate dose coverage during the initial implant, but on detailed analysis, for some patients, areas of underdosing were observed either at the apex or the peripheral zone. Additional seeds were implanted to bring these areas to prescription dose. Intraoperative postplanning is feasible during ultrasound-guided brachytherapy for prostate cancer. Although the postimplant dose-volume histograms for all patients, before the implantation of additional seeds, were adequate according to the American Brachytherapy Society criteria, specific critical areas can be underdosed. Additional seeds can then be implanted to optimize the dosimetry and reduce the risk of underdosing areas of cancer.

CAD-RADS(TM) Coronary Artery Disease - Reporting and Data System. An expert consensus document of the Society of Cardiovascular Computed Tomography (SCCT), the American College of Radiology (ACR) and the North American Society for Cardiovascular Imaging (NASCI). Endorsed by the American College of Cardiology.

PubMed

Cury, Ricardo C; Abbara, Suhny; Achenbach, Stephan; Agatston, Arthur; Berman, Daniel S; Budoff, Matthew J; Dill, Karin E; Jacobs, Jill E; Maroules, Christopher D; Rubin, Geoffrey D; Rybicki, Frank J; Schoepf, U Joseph; Shaw, Leslee J; Stillman, Arthur E; White, Charles S; Woodard, Pamela K; Leipsic, Jonathon A

2016-01-01

The intent of CAD-RADS - Coronary Artery Disease Reporting and Data System is to create a standardized method to communicate findings of coronary CT angiography (coronary CTA) in order to facilitate decision-making regarding further patient management. The suggested CAD-RADS classification is applied on a per-patient basis and represents the highest-grade coronary artery lesion documented by coronary CTA. It ranges from CAD-RADS 0 (Zero) for the complete absence of stenosis and plaque to CAD-RADS 5 for the presence of at least one totally occluded coronary artery and should always be interpreted in conjunction with the impression found in the report. Specific recommendations are provided for further management of patients with stable or acute chest pain based on the CAD-RADS classification. The main goal of CAD-RADS is to standardize reporting of coronary CTA results and to facilitate communication of test results to referring physicians along with suggestions for subsequent patient management. In addition, CAD-RADS will provide a framework of standardization that may benefit education, research, peer-review and quality assurance with the potential to ultimately result in improved quality of care. Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

Smoking-related interstitial fibrosis combined with pulmonary emphysema: computed tomography-pathologic correlative study using lobectomy specimens

PubMed Central

Otani, Hideji; Tanaka, Tomonori; Murata, Kiyoshi; Fukuoka, Junya; Nitta, Norihisa; Nagatani, Yukihiro; Sonoda, Akinaga; Takahashi, Masashi

2016-01-01

Purpose To evaluate the incidence and pathologic correlation of thin-section computed tomography (TSCT) findings in smoking-related interstitial fibrosis (SRIF) with pulmonary emphysema. Patients and methods Our study included 172 consecutive patients who underwent TSCT and subsequent lobectomy. TSCT findings including clustered cysts with visible walls (CCVW) and ground-glass attenuation with/without reticulation (GGAR) were evaluated and compared in nonsmokers and smokers and among lung locations. TSCT findings, especially CCVW, were also compared with histological findings using lobectomy specimens. Results The incidence of CCVW and GGAR was significantly higher in smokers than in nonsmokers (34.1% and 40.7%, respectively, vs 2.0% and 12.2%). CCVW and GGAR were frequently found in the lower and peripheral zones. Histologically, CCVW corresponded more often with SRIF with emphysema than usual interstitial pneumonia (UIP, 63.3% vs 30%). CCVW of irregular size and shape were seen in 19 of 20 SRIF with emphysema and in seven of nine UIP-manifested areas with similar round cysts. A less-involved subpleural parenchyma was observed more frequently in SRIF with emphysema. Conclusion SRIF with emphysema is a more frequent pathological finding than UIP in patients with CCVW on TSCT. The irregular size and shape of CCVW and a less-involved subpleural parenchyma may be a clue suggesting the presence of SRIF with emphysema. PMID:27445472

Morphometric analysis of sex differences in contemporary Japanese pelves using multidetector computed tomography.

PubMed

Torimitsu, Suguru; Makino, Yohsuke; Saitoh, Hisako; Sakuma, Ayaka; Ishii, Namiko; Yajima, Daisuke; Inokuchi, Go; Motomura, Ayumi; Chiba, Fumiko; Yamaguchi, Rutsuko; Hashimoto, Mari; Hoshioka, Yumi; Iwase, Hirotaro

2015-12-01

Sex estimation of decomposed or skeletal remains is clearly important in forensic contexts. Recently, contemporary population-specific data has been obtained using multidetector computed tomography (MDCT) scanning. The main purpose of this study was to investigate skeletal pelvic dimorphism in a contemporary Japanese forensic sample and to quantify the accuracy of sex estimation using various pelvic measurements obtained from three-dimensional (3D) CT images. This study used a total of 208 cadavers (104 males, 104 females) of which postmortem CT scanning and subsequent forensic autopsy were conducted between December 2011 and August 2014. Eleven measurements of each pelvis were obtained from 3D CT reconstructed images that extracted only bone data. The measurements were analyzed using descriptive statistics and discriminant function analyses. All except one measurement were dimorphic in terms of sex differences. Univariate discriminant function analyses using these measurements provided sex classification accuracy rates of 62.0-98.1%. The subpubic angle was found to contribute most significantly to accurate sex estimation. Multivariate discriminant functions yielded sex prediction accuracy rates of 63.9-98.1%. In conclusion, the pelvic measurements obtained from 3D CT images of a contemporary Japanese population successfully demonstrated sexual dimorphism and may be useful for the estimation of skeletal sex in the field of forensic anthropology. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Acute myocardial infarction due to spontaneous, localized, acute dissection of the sinus of Valsalva detected by intravascular ultrasound and electrocardiogram-gated computed tomography.

PubMed

Ichihashi, Taku; Ito, Tsuyoshi; Murai, Shunsuke; Ikehara, Noriyuki; Fujita, Hiroshi; Suda, Hisao; Ohte, Nobuyuki

2016-09-01

A 58-year-old man was referred to our hospital because of chest pain. The 12-lead electrocardiogram (ECG) revealed ST-segment elevation in II, III, and a Vf with advanced heart block. Transthoracic echocardiography demonstrated aortic root dilatation at the sinus of Valsalva, moderate aortic regurgitation, and decreased wall motion in the inferior part of the left ventricle. Non-ECG-gated enhanced computed tomography (CT) did not reveal an aortic dissection. The patient underwent emergent coronary angiography, which revealed a severely narrowed ostium of the right coronary artery (RCA). Percutaneous coronary intervention (PCI) was performed under intravascular ultrasound (IVUS) guidance. IVUS images demonstrated an intimal flap extending from the aortic wall to the proximal RCA, suggesting that a periaortic hematoma in the false lumen compressed the ostium of the RCA, leading to acute myocardial infarction. To recover hemodynamic stability, the RCA ostium was stented. Subsequent ECG-gated enhanced CT clearly depicted the entry point and extension of the dissection localized within the sinus of Valsalva. The dissection likely involved the left main coronary artery and an emergent Bentall procedure was performed. Intraoperative findings confirmed an intimal tear and extension of the dissection. Thus, ECG-gated CT can clearly depict the entry site and extension of a dissection occurring in the localized area that cannot be detected by conventional CT.

Abdominal perforation after rupture of a diamond-studded wire: a case report.

PubMed

Schmelzle, Moritz; Matthaei, Hanno; Tustas, Roy Y; Schmitt, Marcus; Müller-Mattheis, Volker; Linhart, Wolfgang; Eisenberger, Claus F; Knoefel, Wolfram T; Esch, Jan Schulte Am

2008-11-13

There are numerous cases of abdominal injuries due to bullets. Abdominal injuries due to bullets are a diagnostic and therapeutic challenge. Here, an unusual case of an abdominal perforation caused by a metal projectile, lead to confusion in the interpretation of the preoperative computer tomography. We present an unusual case of a 32-year-old male worker who sustained a "shot" to the left upper abdominal quadrant, as a result of a work-related accident. The projectile derived from a special wire that tore during operation. One chain element happened to accelerate towards the patients belly and perforated the abdominal wall. Computer tomography located the radiopaque projectile to the cortex of the left kidney and showed a lesion of the tail of the pancreas. The presence of intraperitoneal free air suggested a gastrointestinal perforation. Immediate open exploration of the peritoneal cavity and the retroperitoneal space revealed perforating lesions of the anterior and posterior gastric wall, as well as the pancreatic tail. The projectile was finally retrieved in the upper pole of the left kidney. The patient had a good clinical course subsequent to surgery and was discharged in good general condition. This case represents a rare form of a retained bullet injury and corroborates the need of sufficient measures of worker-protection in area of diamond-studded wire cutting devices.

Peri-implant assessment via cone beam computed tomography and digital periapical radiography: an ex vivo study.

PubMed

Silveira-Neto, Nicolau; Flores, Mateus Ericson; De Carli, João Paulo; Costa, Max Dória; Matos, Felipe de Souza; Paranhos, Luiz Renato; Linden, Maria Salete Sandini

2017-11-01

This research evaluated detail registration in peri-implant bone using two different cone beam computer tomography systems and a digital periapical radiograph. Three different image acquisition protocols were established for each cone beam computer tomography apparatus, and three clinical situations were simulated in an ex vivo fresh pig mandible: buccal bone defect, peri-implant bone defect, and bone contact. Data were subjected to two analyses: quantitative and qualitative. The quantitative analyses involved a comparison of real specimen measures using a digital caliper in three regions of the preserved buccal bone - A, B and E (control group) - to cone beam computer tomography images obtained with different protocols (kp1, kp2, kp3, ip1, ip2, and ip3). In the qualitative analyses, the ability to register peri-implant details via tomography and digital periapical radiography was verified, as indicated by twelve evaluators. Data were analyzed with ANOVA and Tukey's test (α=0.05). The quantitative assessment showed means statistically equal to those of the control group under the following conditions: buccal bone defect B and E with kp1 and ip1, peri-implant bone defect E with kp2 and kp3, and bone contact A with kp1, kp2, kp3, and ip2. Qualitatively, only bone contacts were significantly different among the assessments, and the p3 results differed from the p1 and p2 results. The other results were statistically equivalent. The registration of peri-implant details was influenced by the image acquisition protocol, although metal artifacts were produced in all situations. The evaluators preferred the Kodak 9000 3D cone beam computer tomography in most cases. The evaluators identified buccal bone defects better with cone beam computer tomography and identified peri-implant bone defects better with digital periapical radiography.

Single-Photon Emission Computed Tomography/Computed Tomography Imaging in a Rabbit Model of Emphysema Reveals Ongoing Apoptosis In Vivo

PubMed Central

Goldklang, Monica P.; Tekabe, Yared; Zelonina, Tina; Trischler, Jordis; Xiao, Rui; Stearns, Kyle; Romanov, Alexander; Muzio, Valeria; Shiomi, Takayuki; Johnson, Lynne L.

2016-01-01

Evaluation of lung disease is limited by the inability to visualize ongoing pathological processes. Molecular imaging that targets cellular processes related to disease pathogenesis has the potential to assess disease activity over time to allow intervention before lung destruction. Because apoptosis is a critical component of lung damage in emphysema, a functional imaging approach was taken to determine if targeting apoptosis in a smoke exposure model would allow the quantification of early lung damage in vivo. Rabbits were exposed to cigarette smoke for 4 or 16 weeks and underwent single-photon emission computed tomography/computed tomography scanning using technetium-99m–rhAnnexin V-128. Imaging results were correlated with ex vivo tissue analysis to validate the presence of lung destruction and apoptosis. Lung computed tomography scans of long-term smoke–exposed rabbits exhibit anatomical similarities to human emphysema, with increased lung volumes compared with controls. Morphometry on lung tissue confirmed increased mean linear intercept and destructive index at 16 weeks of smoke exposure and compliance measurements documented physiological changes of emphysema. Tissue and lavage analysis displayed the hallmarks of smoke exposure, including increased tissue cellularity and protease activity. Technetium-99m–rhAnnexin V-128 single-photon emission computed tomography signal was increased after smoke exposure at 4 and 16 weeks, with confirmation of increased apoptosis through terminal deoxynucleotidyl transferase dUTP nick end labeling staining and increased tissue neutral sphingomyelinase activity in the tissue. These studies not only describe a novel emphysema model for use with future therapeutic applications, but, most importantly, also characterize a promising imaging modality that identifies ongoing destructive cellular processes within the lung. PMID:27483341

Quantitative X-ray fluorescence computed tomography for low-Z samples using an iterative absorption correction algorithm

NASA Astrophysics Data System (ADS)

Huang, Rong; Limburg, Karin; Rohtla, Mehis

2017-05-01

X-ray fluorescence computed tomography is often used to measure trace element distributions within low-Z samples, using algorithms capable of X-ray absorption correction when sample self-absorption is not negligible. Its reconstruction is more complicated compared to transmission tomography, and therefore not widely used. We describe in this paper a very practical iterative method that uses widely available transmission tomography reconstruction software for fluorescence tomography. With this method, sample self-absorption can be corrected not only for the absorption within the measured layer but also for the absorption by material beyond that layer. By combining tomography with analysis for scanning X-ray fluorescence microscopy, absolute concentrations of trace elements can be obtained. By using widely shared software, we not only minimized the coding, took advantage of computing efficiency of fast Fourier transform in transmission tomography software, but also thereby accessed well-developed data processing tools coming with well-known and reliable software packages. The convergence of the iterations was also carefully studied for fluorescence of different attenuation lengths. As an example, fish eye lenses could provide valuable information about fish life-history and endured environmental conditions. Given the lens's spherical shape and sometimes the short distance from sample to detector for detecting low concentration trace elements, its tomography data are affected by absorption related to material beyond the measured layer but can be reconstructed well with our method. Fish eye lens tomography results are compared with sliced lens 2D fluorescence mapping with good agreement, and with tomography providing better spatial resolution.

Radiation-Induced Liver Injury Mimicking Metastatic Disease in a Patient With Esophageal Cancer: Correlation of Positron Emission Tomography/Computed Tomography With Magnetic Resonance Imaging and Literature Review.

PubMed

Rabe, Tiffany M; Yokoo, Takeshi; Meyer, Jeffrey; Kernstine, Kemp H; Wang, David; Khatri, Gaurav

2016-01-01

Post-radiation therapy evaluation of distal esophageal cancers with positron emission tomography/computed tomography can be problematic. Differentiation of recurrent neoplasm from postradiation changes is difficult in areas of fluorodeoxyglucose avidity in adjacent, incidentally irradiated organs. Few studies have described the magnetic resonance imaging appearance of radiation-induced hepatic injury. We report a case of focal radiation-induced liver injury with a new focus of fluorodeoxyglucose uptake on posttreatment positron emission tomography as well as masslike enhancement and signal abnormality on magnetic resonance imaging, thus mimicking new liver metastasis. Correlation with radiation planning images suggested the correct diagnosis, which was confirmed on follow-up imaging.

A multiresolution approach to iterative reconstruction algorithms in X-ray computed tomography.

PubMed

De Witte, Yoni; Vlassenbroeck, Jelle; Van Hoorebeke, Luc

2010-09-01

In computed tomography, the application of iterative reconstruction methods in practical situations is impeded by their high computational demands. Especially in high resolution X-ray computed tomography, where reconstruction volumes contain a high number of volume elements (several giga voxels), this computational burden prevents their actual breakthrough. Besides the large amount of calculations, iterative algorithms require the entire volume to be kept in memory during reconstruction, which quickly becomes cumbersome for large data sets. To overcome this obstacle, we present a novel multiresolution reconstruction, which greatly reduces the required amount of memory without significantly affecting the reconstructed image quality. It is shown that, combined with an efficient implementation on a graphical processing unit, the multiresolution approach enables the application of iterative algorithms in the reconstruction of large volumes at an acceptable speed using only limited resources.

X-ray Computed Tomography.

ERIC Educational Resources Information Center

Michael, Greg

2001-01-01

Describes computed tomography (CT), a medical imaging technique that produces images of transaxial planes through the human body. A CT image is reconstructed mathematically from a large number of one-dimensional projections of a plane. The technique is used in radiological examinations and radiotherapy treatment planning. (Author/MM)

The Power of Computer-aided Tomography to Investigate Marine Benthic Communities

EPA Science Inventory

Utilization of Computer-aided-Tomography (CT) technology is a powerful tool to investigate benthic communities in aquatic systems. In this presentation, we will attempt to summarize our 15 years of experience in developing specific CT methods and applications to marine benthic co...

Three-dimensional evaluation of human jaw bone microarchitecture: correlation between the microarchitectural parameters of cone beam computed tomography and micro-computer tomography.

PubMed

Kim, Jo-Eun; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul; Huh, Kyung-Hoe

2015-12-01

To evaluate the potential feasibility of cone beam computed tomography (CBCT) in the assessment of trabecular bone microarchitecture. Sixty-eight specimens from four pairs of human jaw were scanned using both micro-computed tomography (micro-CT) of 19.37-μm voxel size and CBCT of 100-μm voxel size. The correlation of 3-dimensional parameters between CBCT and micro-CT was evaluated. All parameters, except bone-specific surface and trabecular thickness, showed linear correlations between the 2 imaging modalities (P < .05). Among the parameters, bone volume, percent bone volume, trabecular separation, and degree of anisotropy (DA) of CBCT images showed strong correlations with those of micro-CT images. DA showed the strongest correlation (r = 0.693). Most microarchitectural parameters from CBCT were correlated with those from micro-CT. Some microarchitectural parameters, especially DA, could be used as strong predictors of bone quality in the human jaw. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluation of a continuous-rotation, high-speed scanning protocol for micro-computed tomography.

PubMed

Kerl, Hans Ulrich; Isaza, Cristina T; Boll, Hanne; Schambach, Sebastian J; Nolte, Ingo S; Groden, Christoph; Brockmann, Marc A

2011-01-01

Micro-computed tomography is used frequently in preclinical in vivo research. Limiting factors are radiation dose and long scan times. The purpose of the study was to compare a standard step-and-shoot to a continuous-rotation, high-speed scanning protocol. Micro-computed tomography of a lead grid phantom and a rat femur was performed using a step-and-shoot and a continuous-rotation protocol. Detail discriminability and image quality were assessed by 3 radiologists. The signal-to-noise ratio and the modulation transfer function were calculated, and volumetric analyses of the femur were performed. The radiation dose of the scan protocols was measured using thermoluminescence dosimeters. The 40-second continuous-rotation protocol allowed a detail discriminability comparable to the step-and-shoot protocol at significantly lower radiation doses. No marked differences in volumetric or qualitative analyses were observed. Continuous-rotation micro-computed tomography significantly reduces scanning time and radiation dose without relevantly reducing image quality compared with a normal step-and-shoot protocol.

Management of Liver Cancer Argon-helium Knife Therapy with Functional Computer Tomography Perfusion Imaging.

PubMed

Wang, Hongbo; Shu, Shengjie; Li, Jinping; Jiang, Huijie

2016-02-01

The objective of this study was to observe the change in blood perfusion of liver cancer following argon-helium knife treatment with functional computer tomography perfusion imaging. Twenty-seven patients with primary liver cancer treated with argon-helium knife and were included in this study. Plain computer tomography (CT) and computer tomography perfusion (CTP) imaging were conducted in all patients before and after treatment. Perfusion parameters including blood flows, blood volume, hepatic artery perfusion fraction, hepatic artery perfusion, and hepatic portal venous perfusion were used for evaluating therapeutic effect. All parameters in liver cancer were significantly decreased after argon-helium knife treatment (p < 0.05 to all). Significant decrease in hepatic artery perfusion was also observed in pericancerous liver tissue, but other parameters kept constant. CT perfusion imaging is able to detect decrease in blood perfusion of liver cancer post-argon-helium knife therapy. Therefore, CTP imaging would play an important role for liver cancer management followed argon-helium knife therapy. © The Author(s) 2014.

Characterization of normal feline renal vascular anatomy with dual-phase CT angiography.

PubMed

Cáceres, Ana V; Zwingenberger, Allison L; Aronson, Lillian R; Mai, Wilfried

2008-01-01

Helical computed tomography angiography was used to evaluate the renal vascular anatomy of potential feline renal donors. One hundred and fourteen computed tomography angiograms were reviewed. The vessels were characterized as single without bifurcation, single with bifurcation, double, or triple. Multiplicity was most commonly seen for the right renal vein (45/114 vs. 3/114 multiple left renal veins, 0/114 multiple right renal arteries, and 8/114 multiple left renal arteries). The right kidney was 13.3 times more likely than the left to have multiple renal veins. Additional vascular variants included double caudal vena cava and an accessory renal artery. For the left kidney, surgery and computed tomography angiography findings were in agreement in 92% of 74 cats. For the right kidney, surgery and computed tomography angiography findings were in agreement in 6/6 cats. Our findings of renal vascular anatomy variations in cats were similar to previous reports in humans. Identifying and recognizing the pattern of distribution of these vessels is important when performing renal transplantation.

Stress Computed Tomography Myocardial Perfusion Imaging: A New Topic in Cardiology.

PubMed

Seitun, Sara; Castiglione Morelli, Margherita; Budaj, Irilda; Boccalini, Sara; Galletto Pregliasco, Athena; Valbusa, Alberto; Cademartiri, Filippo; Ferro, Carlo

2016-02-01

Since its introduction about 15 years ago, coronary computed tomography angiography has become today the most accurate clinical instrument for noninvasive assessment of coronary atherosclerosis. Important technical developments have led to a continuous stream of new clinical applications together with a significant reduction in radiation dose exposure. Latest generation computed tomography scanners (≥ 64 slices) allow the possibility of performing static or dynamic perfusion imaging during stress by using coronary vasodilator agents (adenosine, dipyridamole, or regadenoson), combining both functional and anatomical information in the same examination. In this article, the emerging role and state-of-the-art of myocardial computed tomography perfusion imaging are reviewed and are illustrated by clinical cases from our experience with a second-generation dual-source 128-slice scanner (Somatom Definition Flash, Siemens; Erlangen, Germany). Technical aspects, data analysis, diagnostic accuracy, radiation dose and future prospects are reviewed. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Advances in diagnosis and treatment of metastatic cervical cancer

PubMed Central

2016-01-01

Cervical cancer is one of the most common cancers in women worldwide. The outcome of patients with metastatic cervical cancer is poor. We reviewed the relevant literature concerning the treatment and diagnosis of metastatic cervical cancer. There are two types of metastasis related to different treatments and survival rates: hematogenous metastasis and lymphatic metastasis. Patients with hematogenous metastasis have a higher risk of death than those with lymphatic metastasis. In terms of diagnosis, fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) and PET-computed tomography are effective tools for the evaluation of distant metastasis. Concurrent chemoradiotherapy and subsequent chemotherapy are well-tolerated and efficient for lymphatic metastasis. As for lung metastasis, chemotherapy and/or surgery are valuable treatments for resistant, recurrent metastatic cervical cancer and chemoradiotherapy may be the optimal choice for stage IVB cervical cancer. Chemotherapy and bone irradiation are promising for bone metastasis. A better survival is achieved with multimodal therapy. Craniotomy or stereotactic radiosurgery is an optimal choice combined with radiotherapy for solitary brain metastases. Chemotherapy and palliative brain radiation may be considered for multiple brain metastases and other organ metastases. PMID:27171673

Aptamer-Targeted Plasmonic Photothermal Therapy of Cancer.

PubMed

Kolovskaya, Olga S; Zamay, Tatiana N; Belyanina, Irina V; Karlova, Elena; Garanzha, Irina; Aleksandrovsky, Aleksandr S; Kirichenko, Andrey; Dubynina, Anna V; Sokolov, Alexey E; Zamay, Galina S; Glazyrin, Yury E; Zamay, Sergey; Ivanchenko, Tatiana; Chanchikova, Natalia; Tokarev, Nikolay; Shepelevich, Nikolay; Ozerskaya, Anastasia; Badrin, Evgeniy; Belugin, Kirill; Belkin, Simon; Zabluda, Vladimir; Gargaun, Ana; Berezovski, Maxim V; Kichkailo, Anna S

2017-12-15

Novel nanoscale bioconjugates combining unique plasmonic photothermal properties of gold nanoparticles (AuNPs) with targeted delivery using cell-specific DNA aptamers have a tremendous potential for medical diagnostics and therapy of many cell-based diseases. In this study, we demonstrate the high anti-cancer activity of aptamer-conjugated, 37-nm spherical gold nanoparticles toward Ehrlich carcinoma in tumor-bearing mice after photothermal treatment. The synthetic anti-tumor aptamers bring the nanoparticles precisely to the desired cells and selectively eliminate cancer cells after the subsequent laser treatment. To prove tumor eradication, we used positron emission tomography (PET) utilizing radioactive glucose and computer tomography, followed by histological analysis of cancer tissue. Three injections of aptamer-conjugated AuNPs and 5 min of laser irradiations are enough to make the tumor undetectable by PET. Histological analysis proves PET results and shows lower damage of healthy tissue in addition to a higher treatment efficiency and selectivity of the gold nanoparticles functionalized with aptamers in comparison to control experiments using free unconjugated nanoparticles. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Identification of interfaces involved in weak interactions with application to F-actin-aldolase rafts.

PubMed

Hu, Guiqing; Taylor, Dianne W; Liu, Jun; Taylor, Kenneth A

2018-03-01

Macromolecular interactions occur with widely varying affinities. Strong interactions form well defined interfaces but weak interactions are more dynamic and variable. Weak interactions can collectively lead to large structures such as microvilli via cooperativity and are often the precursors of much stronger interactions, e.g. the initial actin-myosin interaction during muscle contraction. Electron tomography combined with subvolume alignment and classification is an ideal method for the study of weak interactions because a 3-D image is obtained for the individual interactions, which subsequently are characterized collectively. Here we describe a method to characterize heterogeneous F-actin-aldolase interactions in 2-D rafts using electron tomography. By forming separate averages of the two constituents and fitting an atomic structure to each average, together with the alignment information which relates the raw motif to the average, an atomic model of each crosslink is determined and a frequency map of contact residues is computed. The approach should be applicable to any large structure composed of constituents that interact weakly and heterogeneously. Copyright © 2017 Elsevier Inc. All rights reserved.

Advances in diagnosis and treatment of metastatic cervical cancer.

PubMed

Li, Haoran; Wu, Xiaohua; Cheng, Xi

2016-07-01

Cervical cancer is one of the most common cancers in women worldwide. The outcome of patients with metastatic cervical cancer is poor. We reviewed the relevant literature concerning the treatment and diagnosis of metastatic cervical cancer. There are two types of metastasis related to different treatments and survival rates: hematogenous metastasis and lymphatic metastasis. Patients with hematogenous metastasis have a higher risk of death than those with lymphatic metastasis. In terms of diagnosis, fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) and PET-computed tomography are effective tools for the evaluation of distant metastasis. Concurrent chemoradiotherapy and subsequent chemotherapy are well-tolerated and efficient for lymphatic metastasis. As for lung metastasis, chemotherapy and/or surgery are valuable treatments for resistant, recurrent metastatic cervical cancer and chemoradiotherapy may be the optimal choice for stage IVB cervical cancer. Chemotherapy and bone irradiation are promising for bone metastasis. A better survival is achieved with multimodal therapy. Craniotomy or stereotactic radiosurgery is an optimal choice combined with radiotherapy for solitary brain metastases. Chemotherapy and palliative brain radiation may be considered for multiple brain metastases and other organ metastases.

18 F-sodium fluoride positron emission tomography of the equine distal limb: Exploratory study in three horses.

PubMed

Spriet, M; Espinosa, P; Kyme, A Z; Phillips, K L; Katzman, S A; Galuppo, L D; Stepanov, P; Beylin, D

2018-01-01

Positron emission tomography (PET) is a cross-sectional, functional imaging modality that has recently become available to the horse. The use of 18 F-sodium fluoride ( 18 F-NaF), a PET bone tracer, has not previously been reported in this species. To assess the feasibility of 18 F-NaF PET in the equine distal limb and explore possible applications in the horse in comparison with other imaging modalities. Exploratory descriptive study involving three research horses. Horses were placed under general anaesthesia prior to intravenous (i.v.) administration of 1.5 MBq/kg of 18 F-NaF. Positron emission tomography imaging of both front feet and fetlocks was performed using a portable scanner. Computed tomography (CT) of the distal limb was performed under a separate anaesthetic episode. Bone scintigraphy and magnetic resonance imaging (MRI) were subsequently performed under standing sedation. Images obtained from PET and other imaging modalities were independently assessed and the results correlated. Positron emission tomography images were obtained without complication. The radiation exposure rate was similar to equine bone scintigraphy. Positron emission tomography detected focal 18 F-NaF uptake in areas where other imaging modalities did not identify any abnormalities. This included sites of ligamentous attachment, subchondral compact bone plate and the flexor cortex of the navicular bone. 18 F-NaF uptake was identified in some, but not all, osseous fragments and areas of osseous formation, suggesting a distinction between active and inactive lesions. A small number of horses were included and histopathology was not available. 18 F-NaF PET imaging of the equine distal limb provides useful additional information when compared with CT, MRI and scintigraphy and has the potential for both research and clinical applications in the horse. The Summary is available in Chinese - see Supporting information. © 2017 EVJ Ltd.

Fatal Road Traffic Vehicle Collisions With Pedestrian Victims: Forensic Postmortem Computed Tomography and Autopsy Correlation.

PubMed

Chatzaraki, Vasiliki; Thali, Michael J; Ampanozi, Garyfalia; Schweitzer, Wolf

2018-06-01

Fatal car-to-pedestrian collisions regularly appear in the forensic pathologist's routine, particularly in places of extended urbanization. Postmortem computed tomography has gained an exceptional role to supplement autopsy worldwide, giving information that is supplementary or complimentary to conventional autopsy. In this retrospective study, a total number of 320 findings in a series of 21 pedestrians fatally hit by cars and trucks of both postmortem computed tomography and autopsy were correlated. According to our results, it is best to combine both methods to give well-founded answers to questions pertaining to both collision reconstruction and cause of death.

[Axial computer tomography of the neurocranium (author's transl)].

PubMed

Stöppler, L

1977-05-27

Computer tomography (CT), a new radiographic examination technique, is very highly efficient, for it has high informative content with little stress for the patient. In contrast to the conventional X-ray technology, CT succeeds, by direct presentation of the structure of the soft parts, in obtaining information which comes close to that of macroscopic neuropathology. The capacity and limitations of the method at the present stage of development are reported. Computer tomography cannot displace conventional neuroradiological methods of investigation, although it is rightly presented as a screening method and helps towards selective use. Indications, technical integration and handling of CT are prerequisites for the exhaustive benefit of the excellent new technique.

Ambient noise adjoint tomography for a linear array in North China

NASA Astrophysics Data System (ADS)

Zhang, C.; Yao, H.; Liu, Q.; Yuan, Y. O.; Zhang, P.; Feng, J.; Fang, L.

2017-12-01

Ambient noise tomography based on dispersion data and ray theory has been widely utilized for imaging crustal structures. In order to improve the inversion accuracy, ambient noise tomography based on the 3D adjoint approach or full waveform inversion has been developed recently, however, the computational cost is tremendous. In this study we present 2D ambient noise adjoint tomography for a linear array in north China with significant computational efficiency compared to 3D ambient noise adjoint tomography. During the preprocessing, we first convert the observed data in 3D media, i.e., surface-wave empirical Green's functions (EGFs) from ambient noise cross-correlation, to the reconstructed EGFs in 2D media using a 3D/2D transformation scheme. Different from the conventional steps of measuring phase dispersion, the 2D adjoint tomography refines 2D shear wave speeds along the profile directly from the reconstructed Rayleigh wave EGFs in the period band 6-35s. With the 2D initial model extracted from the 3D model from traditional ambient noise tomography, adjoint tomography updates the model by minimizing the frequency-dependent Rayleigh wave traveltime misfits between the reconstructed EGFs and synthetic Green function (SGFs) in 2D media generated by the spectral-element method (SEM), with a preconditioned conjugate gradient method. The multitaper traveltime difference measurement is applied in four period bands during the inversion: 20-35s, 15-30s, 10-20s and 6-15s. The recovered model shows more detailed crustal structures with pronounced low velocity anomaly in the mid-lower crust beneath the junction of Taihang Mountains and Yin-Yan Mountains compared with the initial model. This low velocity structure may imply the possible intense crust-mantle interactions, probably associated with the magmatic underplating during the Mesozoic to Cenozoic evolution of the region. To our knowledge, it's first time that ambient noise adjoint tomography is implemented in 2D media. Considering the intensive computational cost and storage of 3D adjoint tomography, this 2D ambient noise adjoint tomography has potential advantages to get high-resolution 2D crustal structures with limited computational resource.

X-Ray Radiography of Gas Turbine Ceramics.

DTIC Science & Technology

1979-10-20

Microfocus X-ray equipment. 1a4ihe definition of equipment concepts for a computer assisted tomography ( CAT ) system; and 4ffthe development of a CAT ...were obtained from these test coupons using Microfocus X-ray and image en- hancement techniques. A Computer Assisted Tomography ( CAT ) design concept...monitor. Computer reconstruction algorithms were investigated with respect to CAT and a preferred approach was determined. An appropriate CAT algorithm

RADIAL COMPUTED TOMOGRAPHY OF AIR CONTAMINANTS USING OPTICAL REMOTE SENSING

EPA Science Inventory

The paper describes the application of an optical remote-sensing (ORS) system to map air contaminants and locate fugitive emissions. Many ORD systems may utilize radial non-overlapping beam geometry and a computed tomography (CT) algorithm to map the concentrations in a plane. In...

Micro computed tomography (CT) scanned anatomical gateway to insect pest bioinformatics

USDA-ARS?s Scientific Manuscript database

An international collaboration to establish an interactive Digital Video Library for a Systems Biology Approach to study the Asian citrus Psyllid and psyllid genomics/proteomics interactions is demonstrated. Advances in micro-CT, digital computed tomography (CT) scan uses X-rays to make detailed pic...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

Accuracy of single-pass whole-body computed tomography for detection of injuries in patients with major blunt trauma

PubMed Central

Stengel, Dirk; Ottersbach, Caspar; Matthes, Gerrit; Weigeldt, Moritz; Grundei, Simon; Rademacher, Grit; Tittel, Anja; Mutze, Sven; Ekkernkamp, Axel; Frank, Matthias; Schmucker, Uli; Seifert, Julia

2012-01-01

Background: Contrast-enhanced whole-body computed tomography (also called “pan-scanning”) is considered to be a conclusive diagnostic tool for major trauma. We sought to determine the accuracy of this method, focusing on the reliability of negative results. Methods: Between July 2006 and December 2008, a total of 982 patients with suspected severe injuries underwent single-pass pan-scanning at a metropolitan trauma centre. The findings of the scan were independently evaluated by two reviewers who analyzed the injuries to five body regions and compared the results to a synopsis of hospital charts, subsequent imaging and interventional procedures. We calculated the sensitivity and specificity of the pan-scan for each body region, and we assessed the residual risk of missed injuries that required surgery or critical care. Results: A total of 1756 injuries were detected in the 982 patients scanned. Of these, 360 patients had an Injury Severity Score greater than 15. The median length of follow-up was 39 (interquartile range 7–490) days, and 474 patients underwent a definitive reference test. The sensitivity of the initial pan-scan was 84.6% for head and neck injuries, 79.6% for facial injuries, 86.7% for thoracic injuries, 85.7% for abdominal injuries and 86.2% for pelvic injuries. Specificity was 98.9% for head and neck injuries, 99.1% for facial injuries, 98.9% for thoracic injuries, 97.5% for abdominal injuries and 99.8% for pelvic injuries. In total, 62 patients had 70 missed injuries, indicating a residual risk of 6.3% (95% confidence interval 4.9%–8.0%). Interpretation: We found that the positive results of trauma pan-scans are conclusive but negative results require subsequent confirmation. The pan-scan algorithms reduce, but do not eliminate, the risk of missed injuries, and they should not replace close monitoring and clinical follow-up of patients with major trauma. PMID:22392949

Computer-aided diagnosis and artificial intelligence in clinical imaging.

PubMed

Shiraishi, Junji; Li, Qiang; Appelbaum, Daniel; Doi, Kunio

2011-11-01

Computer-aided diagnosis (CAD) is rapidly entering the radiology mainstream. It has already become a part of the routine clinical work for the detection of breast cancer with mammograms. The computer output is used as a "second opinion" in assisting radiologists' image interpretations. The computer algorithm generally consists of several steps that may include image processing, image feature analysis, and data classification via the use of tools such as artificial neural networks (ANN). In this article, we will explore these and other current processes that have come to be referred to as "artificial intelligence." One element of CAD, temporal subtraction, has been applied for enhancing interval changes and for suppressing unchanged structures (eg, normal structures) between 2 successive radiologic images. To reduce misregistration artifacts on the temporal subtraction images, a nonlinear image warping technique for matching the previous image to the current one has been developed. Development of the temporal subtraction method originated with chest radiographs, with the method subsequently being applied to chest computed tomography (CT) and nuclear medicine bone scans. The usefulness of the temporal subtraction method for bone scans was demonstrated by an observer study in which reading times and diagnostic accuracy improved significantly. An additional prospective clinical study verified that the temporal subtraction image could be used as a "second opinion" by radiologists with negligible detrimental effects. ANN was first used in 1990 for computerized differential diagnosis of interstitial lung diseases in CAD. Since then, ANN has been widely used in CAD schemes for the detection and diagnosis of various diseases in different imaging modalities, including the differential diagnosis of lung nodules and interstitial lung diseases in chest radiography, CT, and position emission tomography/CT. It is likely that CAD will be integrated into picture archiving and communication systems and will become a standard of care for diagnostic examinations in daily clinical work. Copyright © 2011 Elsevier Inc. All rights reserved.

A computer-aided system for automatic extraction of femur neck trabecular bone architecture using isotropic volume construction from clinical hip computed tomography images.

PubMed

Vivekanandhan, Sapthagirivasan; Subramaniam, Janarthanam; Mariamichael, Anburajan

2016-10-01

Hip fractures due to osteoporosis are increasing progressively across the globe. It is also difficult for those fractured patients to undergo dual-energy X-ray absorptiometry scans due to its complicated protocol and its associated cost. The utilisation of computed tomography for the fracture treatment has become common in the clinical practice. It would be helpful for orthopaedic clinicians, if they could get some additional information related to bone strength for better treatment planning. The aim of our study was to develop an automated system to segment the femoral neck region, extract the cortical and trabecular bone parameters, and assess the bone strength using an isotropic volume construction from clinical computed tomography images. The right hip computed tomography and right femur dual-energy X-ray absorptiometry measurements were taken from 50 south-Indian females aged 30-80 years. Each computed tomography image volume was re-constructed to form isotropic volumes. An automated system by incorporating active contour models was used to segment the neck region. A minimum distance boundary method was applied to isolate the cortical and trabecular bone components. The trabecular bone was enhanced and segmented using trabecular enrichment approach. The cortical and trabecular bone features were extracted and statistically compared with dual-energy X-ray absorptiometry measured femur neck bone mineral density. The extracted bone measures demonstrated a significant correlation with neck bone mineral density (r > 0.7, p < 0.001). The inclusion of cortical measures, along with the trabecular measures extracted after isotropic volume construction and trabecular enrichment approach procedures, resulted in better estimation of bone strength. The findings suggest that the proposed system using the clinical computed tomography images scanned with low dose could eventually be helpful in osteoporosis diagnosis and its treatment planning. © IMechE 2016.

Direct estimation of human trabecular bone stiffness using cone beam computed tomography.

PubMed

Klintström, Eva; Klintström, Benjamin; Pahr, Dieter; Brismar, Torkel B; Smedby, Örjan; Moreno, Rodrigo

2018-04-10

The aim of this study was to evaluate the possibility of estimating the biomechanical properties of trabecular bone through finite element simulations by using dental cone beam computed tomography data. Fourteen human radius specimens were scanned in 3 cone beam computed tomography devices: 3-D Accuitomo 80 (J. Morita MFG., Kyoto, Japan), NewTom 5 G (QR Verona, Verona, Italy), and Verity (Planmed, Helsinki, Finland). The imaging data were segmented by using 2 different methods. Stiffness (Young modulus), shear moduli, and the size and shape of the stiffness tensor were studied. Corresponding evaluations by using micro-CT were regarded as the reference standard. The 3-D Accuitomo 80 (J. Morita MFG., Kyoto, Japan) showed good performance in estimating stiffness and shear moduli but was sensitive to the choice of segmentation method. NewTom 5 G (QR Verona, Verona, Italy) and Verity (Planmed, Helsinki, Finland) yielded good correlations, but they were not as strong as Accuitomo 80 (J. Morita MFG., Kyoto, Japan). The cone beam computed tomography devices overestimated both stiffness and shear compared with the micro-CT estimations. Finite element-based calculations of biomechanics from cone beam computed tomography data are feasible, with strong correlations for the Accuitomo 80 scanner (J. Morita MFG., Kyoto, Japan) combined with an appropriate segmentation method. Such measurements might be useful for predicting implant survival by in vivo estimations of bone properties. Copyright © 2018 Elsevier Inc. All rights reserved.

Cutaneous nocardiosis in two dogs receiving ciclosporin therapy for the management of canine atopic dermatitis.

PubMed

Siak, Meng K; Burrows, Amanda K

2013-08-01

Ciclosporin is a calcineurin inhibitor that is currently registered for the treatment of canine atopic dermatitis. The most common adverse effects include mild, transient gastrointestinal disturbances. Single case reports of opportunistic infections due to Nocardia spp., Neospora spp. and papillomaviruses have also been reported. Clinicians should be aware of the potential risk of systemic immunosuppression and subsequent infection with Nocardia spp. in dogs receiving ciclosporin. Cutaneous nocardiosis in two dogs receiving ciclosporin therapy for management of canine atopic dermatitis. Histopathology, PCR for Nocardia spp. and computed tomography. One dog developed disseminated nocardiosis due to Nocardia brasiliensis and a second dog developed localized cutaneous nocardiosis due to a novel Nocardia species subsequent to ciclosporin administration at the recommended dose rate for the management of canine atopic dermatitis. The second case was receiving a combination of ciclosporin and ketoconazole, and serum trough ciclosporin levels were elevated. Clinicians should be aware of the potential risk of systemic immunosuppression and subsequent infection with Nocardia spp. in dogs receiving ciclosporin. Measurement of serum ciclosporin levels may be useful in identifying those individuals which are at risk of opportunistic infections. © 2013 ESVD and ACVD.

Computed microtomography visualization and quantification of mouse ischemic brain lesion by nonionic radio contrast agents

PubMed Central

Dobrivojević, Marina; Bohaček, Ivan; Erjavec, Igor; Gorup, Dunja; Gajović, Srećko

2013-01-01

Aim To explore the possibility of brain imaging by microcomputed tomography (microCT) using x-ray contrasting methods to visualize mouse brain ischemic lesions after middle cerebral artery occlusion (MCAO). Methods Isolated brains were immersed in ionic or nonionic radio contrast agent (RCA) for 5 days and subsequently scanned using microCT scanner. To verify whether ex-vivo microCT brain images can be used to characterize ischemic lesions, they were compared to Nissl stained serial histological sections of the same brains. To verify if brains immersed in RCA may be used afterwards for other methods, subsequent immunofluorescent labeling with anti-NeuN was performed. Results Nonionic RCA showed better gray to white matter contrast in the brain, and therefore was selected for further studies. MicroCT measurement of ischemic lesion size and cerebral edema significantly correlated with the values determined by Nissl staining (ischemic lesion size: P=0.0005; cerebral edema: P=0.0002). Brain immersion in nonionic RCA did not affect subsequent immunofluorescent analysis and NeuN immunoreactivity. Conclusion MicroCT method was proven to be suitable for delineation of the ischemic lesion from the non-infarcted tissue, and quantification of lesion volume and cerebral edema. PMID:23444240

Computed microtomography visualization and quantification of mouse ischemic brain lesion by nonionic radio contrast agents.

PubMed

Dobrivojević, Marina; Bohaček, Ivan; Erjavec, Igor; Gorup, Dunja; Gajović, Srećko

2013-02-01

To explore the possibility of brain imaging by microcomputed tomography (microCT) using x-ray contrasting methods to visualize mouse brain ischemic lesions after middle cerebral artery occlusion (MCAO). Isolated brains were immersed in ionic or nonionic radio contrast agent (RCA) for 5 days and subsequently scanned using microCT scanner. To verify whether ex-vivo microCT brain images can be used to characterize ischemic lesions, they were compared to Nissl stained serial histological sections of the same brains. To verify if brains immersed in RCA may be used afterwards for other methods, subsequent immunofluorescent labeling with anti-NeuN was performed. Nonionic RCA showed better gray to white matter contrast in the brain, and therefore was selected for further studies. MicroCT measurement of ischemic lesion size and cerebral edema significantly correlated with the values determined by Nissl staining (ischemic lesion size: P=0.0005; cerebral edema: P=0.0002). Brain immersion in nonionic RCA did not affect subsequent immunofluorescent analysis and NeuN immunoreactivity. MicroCT method was proven to be suitable for delineation of the ischemic lesion from the non-infarcted tissue, and quantification of lesion volume and cerebral edema.

Miscellaneous indications in bone scintigraphy: metabolic bone diseases and malignant bone tumors.

PubMed

Cook, Gary J R; Gnanasegaran, Gopinath; Chua, Sue

2010-01-01

The diphosphonate bone scan is ideally suited to assess many global, focal or multifocal metabolic bone disorders and there remains a role for conventional bone scintigraphy in metabolic bone disorders at diagnosis, investigation of complications, and treatment response assessment. In contrast, the role of bone scintigraphy in the evaluation of primary malignant bone tumors has reduced with the improvement of morphologic imaging, such as computed tomography and magnetic resonance imaging. However, an increasing role for (18)F-fluorodeoxyglucose positron emission tomography and positron emission tomography/computed tomography is emerging as a functional assessment at diagnosis, staging, and neoadjuvant treatment response assessment.

Usefulness of fluorodeoxyglucose positron emission tomography/computed tomography for detection of a neuroblastic nodule in a ganglioneuroblastoma: a case report.

PubMed

Takeda, Yuka; Sano, Hideki; Kawano, Asuka; Mochizuki, Kazuhiro; Takahashi, Nobuhisa; Kobayashi, Shogo; Ohara, Yoshihiro; Tasaki, Kazuhiro; Hosoya, Mitusuaki; Kikuta, Atsushi

2018-05-03

Ganglioneuroblastoma, nodular is defined as a composite tumor of biologically distinct clones. The peripheral neuroblastic tumors in this category are characterized by the presence of grossly visible neuroblastoma nodules coexisting with ganglioneuroblastoma, intermixed, or with ganglioneuroma. Making a correct diagnosis of ganglioneuroblastoma, nodular is often difficult by biopsy or partial tumor resection, because the neuroblastic nodule could be hidden and not sampled for pathological examination. We report a case of a Japanese boy aged 3 years, 8 months, with an unresectable abdominal tumor and elevated vanillylmandelic acid and homovanillic acid levels. The initial biopsy was ganglioneuroma. However, after the second biopsy from a hidden neuroblastoma nodule that was clearly highlighted by fluorodeoxyglucose positron emission tomography/computed tomography, we reached the diagnosis of ganglioneuroblastoma, nodular. Because the nodule demonstrated neuroblastoma, differentiating subtype, with a low mitosis-karyorrhexis index (favorable histology) and nonamplified MYCN, the boy was treated according to the intermediate-risk protocol and is now alive and well 4 years after the diagnosis. This case illustrates the critical role of fluorodeoxyglucose positron emission tomography/computed tomography for detecting a neuroblastoma nodule in a ganglioneuroblastoma.

FDG-PET/CT in the evaluation of anal carcinoma

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

Cotter, Shane E.; Medical Scientist Training Program, Washington University School of Medicine, St. Louis, MO; Grigsby, Perry W.

2006-07-01

Purpose: Surgical staging and treatment of anal carcinoma has been replaced by noninvasive staging studies and combined modality therapy. In this study, we compare computed tomography (CT) and physical examination to [{sup 18}F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) in the staging of carcinoma of the anal canal, with special emphasis on determination of spread to inguinal lymph nodes. Methods and Materials: Between July 2003 and July 2005, 41 consecutive patients with biopsy-proved anal carcinoma underwent a complete staging evaluation including physical examination, CT, and 2-FDG-PET/CT. Patients ranged in age from 30 to 89 years. Nine men were HIV-positive. Treatment was withmore » standard Nigro regimen. Results: [{sup 18}F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) detected 91% of nonexcised primary tumors, whereas CT visualized 59%. FDG-PET/CT detected abnormal uptake in pelvic nodes of 5 patients with normal pelvic CT scans. FDG-PET/CT detected abnormal nodes in 20% of groins that were normal by CT, and in 23% without abnormality on physical examination. Furthermore, 17% of groins negative by both CT and physical examination showed abnormal uptake on FDG-PET/CT. HIV-positive patients had an increased frequency of PET-positive lymph nodes. Conclusion: [{sup 18}F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography detects the primary tumor more often than CT. FDG-PET/CT detects substantially more abnormal inguinal lymph nodes than are identified by standard clinical staging with CT and physical examination.« less

Segmenting root systems in xray computed tomography images using level sets

USDA-ARS?s Scientific Manuscript database

The segmentation of plant roots from soil and other growing mediums in xray computed tomography images is needed to effectively study the shapes of roots without excavation. However, segmentation is a challenging problem in this context because the root and non-root regions share similar features. ...

Retroperitoneal tumour radiotherapy: clinical improvements using kilovoltage cone beam computed tomography.

PubMed

Juan-Senabre, Xavier J; Ferrer-Albiach, Carlos; Rodríguez-Cordón, Marta; Santos-Serra, Agustín; López-Tarjuelo, Juan; Calzada-Feliu, Salvador

2009-04-01

We present a clinical case of a patient diagnosed with a retroperitoneal sarcoma, which received preoperative treatment with daily verification via computed tomography obtained with kilovoltage cone beam. We compare the benefit of this treatment compared to other conventional treatment without image guiding, reporting quantitative results.

Imaging Techniques in Endodontics: An Overview

PubMed Central

Deepak, B. S.; Subash, T. S.; Narmatha, V. J.; Anamika, T.; Snehil, T. K.; Nandini, D. B.

2012-01-01

This review provides an overview of the relevance of imaging techniques such as, computed tomography, cone beam computed tomography, and ultrasound, to endodontic practice. Many limitations of the conventional radiographic techniques have been overcome by the newer methods. Advantages and disadvantages of various imaging techniques in endodontic practice are also discussed. PMID:22530184

SIMULATION STUDY FOR GASEOUS FLUXES FROM AN AREA SOURCE USING COMPUTED TOMOGRAPHY AND OPTICAL REMOTE SENSING

EPA Science Inventory

The paper presents a new approach to quantifying emissions from fugitive gaseous air pollution sources. Computed tomography (CT) and path-integrated optical remote sensing (PI-ORS) concentration data are combined in a new field beam geometry. Path-integrated concentrations are ...

Computed tomography as a diagnostic aid for extracanal invasive resorption.

PubMed

Kim, Euiseong; Kim, Kee-Deog; Roh, Byoung-Duck; Cho, Yong-Sik; Lee, Seung-Jong

2003-07-01

A case of multiple extracanal invasive resorption is reported. The patient had a history of hypothyroidism for approximately 1 yr before the dental visit. Utilization of computed tomography and a rapid prototyping tooth model in diagnosing the exact location and the size of the resorption area are discussed.

Single photon emission computed tomography in motor neuron disease with dementia.

PubMed

Sawada, H; Udaka, F; Kishi, Y; Seriu, N; Mezaki, T; Kameyama, M; Honda, M; Tomonobu, M

1988-01-01

Single photon emission computed tomography with [123 I] isopropylamphetamine was carried out on a patient with motor neuron disease with dementia. [123 I] uptake was decreased in the frontal lobes. This would reflect the histopathological findings such as neuronal loss and gliosis in the frontal lobes.

APPLICATION OF 3D COMPUTER-AIDED TOMOGRAPHY TO THE QUANTIFICATION OF MARINE SEDIMENT COMMUNITIES IN POLLUTION GRADIENTS

EPA Science Inventory

Computer-Aided Tomography (CT) has been demonstrated to be a cost efficient tool for the qualitative and quantitative study of estuarine benthic communities along pollution gradients.
Now we have advanced this technology to successfully visualize and discriminate three dimen...

Spatial image modulation to improve performance of computed tomography imaging spectrometer

NASA Technical Reports Server (NTRS)

Bearman, Gregory H. (Inventor); Wilson, Daniel W. (Inventor); Johnson, William R. (Inventor)

2010-01-01

Computed tomography imaging spectrometers ("CTIS"s) having patterns for imposing spatial structure are provided. The pattern may be imposed either directly on the object scene being imaged or at the field stop aperture. The use of the pattern improves the accuracy of the captured spatial and spectral information.

Advanced imaging in COPD: insights into pulmonary pathophysiology

PubMed Central

Milne, Stephen

2014-01-01

Chronic obstructive pulmonary disease (COPD) involves a complex interaction of structural and functional abnormalities. The two have long been studied in isolation. However, advanced imaging techniques allow us to simultaneously assess pathological processes and their physiological consequences. This review gives a comprehensive account of the various advanced imaging modalities used to study COPD, including computed tomography (CT), magnetic resonance imaging (MRI), and the nuclear medicine techniques positron emission tomography (PET) and single-photon emission computed tomography (SPECT). Some more recent developments in imaging technology, including micro-CT, synchrotron imaging, optical coherence tomography (OCT) and electrical impedance tomography (EIT), are also described. The authors identify the pathophysiological insights gained from these techniques, and speculate on the future role of advanced imaging in both clinical and research settings. PMID:25478198

Viewing Welds By Computer Tomography

NASA Technical Reports Server (NTRS)

Pascua, Antonio G.; Roy, Jagatjit

1990-01-01

Computer tomography system used to inspect welds for root penetration. Source illuminates rotating welded part with fan-shaped beam of x rays or gamma rays. Detectors in circular array on opposite side of part intercept beam and convert it into electrical signals. Computer processes signals into image of cross section of weld. Image displayed on video monitor. System offers only nondestructive way to check penetration from outside when inner surfaces inaccessible.

Comparison of computed tomography with radiography as a noninvasive diagnostic technique for chronic nasal disease in dogs.

PubMed

Codner, E C; Lurus, A G; Miller, J B; Gavin, P R; Gallina, A; Barbee, D D

1993-04-01

Computed tomography was evaluated as a noninvasive technique for the diagnosis of chronic nasal disease in dogs. Computed tomographic images, radiographs, and histopathologic findings were compared in 11 dogs with chronic nasal disease. Definitive diagnosis was made following traumatic nasal flush, exploratory surgery, or necropsy. The study included 8 dogs with intranasal tumors, 2 dogs with bacterial rhinitis (Pasteurella sp), and 1 dog with mycotic rhinitis (Aspergillus sp). Computed tomography was superior to radiography in defining the extent of the disease process and in differentiating infectious rhinitis from nasal neoplasms. It defined lesions in the palate, nasopharyngeal meatus, maxillary sinus, caudal ethmoturbinates, and periorbital tissues that were difficult to demonstrate by use of conventional radiography. Tumors appeared as space-occupying lesions that obliterated the turbinates, caused deviation of the nasal septum, and eroded bone. Rhinitis appeared as a cavitating lesion that spared the paranasal sinuses, thickened and distorted the turbinates, and widened the meatus. Although morphologically distinct on computed tomographic images, infectious rhinitis and nasal neoplasms could not be differentiated by attenuation measurements or degree of contrast enhancement. Computed tomography appeared to be a reliable, noninvasive technique for the diagnosis of chronic nasal disease in dogs, and a promising alternative to diagnostic techniques currently in use.

[CONE BEAM COMPUTED TOMOGRAPHY IN DIAGNOSTICS OF ODONTOGENIC MAXILLARY SINUSITIS (CASE REPORTS)].

PubMed

Demidova, E; Khurdzidze, G

2017-06-01

Diagnostic studies performed by cone beam computed tomography Morita 3D made possible to obtain high resolution images of hard tissues of upper jawbone and maxillary sinus, to detect bony tissue defects, such as odontogenic cysts, cystogranulomas and granulomas. High-resolution and three dimensional tomographic image reconstructions allowed for optimal and prompt determination of the scope of surgical treatment and planning of effective conservative treatment regimen. Interactive diagnostics helped to estimate cosmetic and functional results of surgical treatment, to prevent the occurrence of surgical complications, and to evaluate the efficacy of conservative treatment. The obtained data contributed to determination of particular applications of cone beam computed tomography in the diagnosis of odontogenic maxillary sinusitis, detection of specific defects with cone beam tomography as the most informative method of diagnosis; as well as to determination of weak and strong sides, and helped to offer mechanisms of x-ray diagnostics to dental surgeons and ENT specialists.

Dynamic contrast enhanced CT in nodule characterization: How we review and report.

PubMed

Qureshi, Nagmi R; Shah, Andrew; Eaton, Rosemary J; Miles, Ken; Gilbert, Fiona J

2016-07-18

Incidental indeterminate solitary pulmonary nodules (SPN) that measure less than 3 cm in size are an increasingly common finding on computed tomography (CT) worldwide. Once identified there are a number of imaging strategies that can be performed to help with nodule characterization. These include interval CT, dynamic contrast enhanced computed tomography (DCE-CT), (18)F-fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG-PET-CT). To date the most cost effective and efficient non-invasive test or combination of tests for optimal nodule characterization has yet to be determined.DCE-CT is a functional test that involves the acquisition of a dynamic series of images of a nodule before and following the administration of intravenous iodinated contrast medium. This article provides an overview of the current indications and limitations of DCE- CT in nodule characterization and a systematic approach to how to perform, analyse and interpret a DCE-CT scan.

Comparative study of cranial anthropometric measurement by traditional calipers to computed tomography and three-dimensional photogrammetry.

PubMed

Mendonca, Derick A; Naidoo, Sybill D; Skolnick, Gary; Skladman, Rachel; Woo, Albert S

2013-07-01

Craniofacial anthropometry by direct caliper measurements is a common method of quantifying the morphology of the cranial vault. New digital imaging modalities including computed tomography and three-dimensional photogrammetry are similarly being used to obtain craniofacial surface measurements. This study sought to compare the accuracy of anthropometric measurements obtained by calipers versus 2 methods of digital imaging.Standard anterior-posterior, biparietal, and cranial index measurements were directly obtained on 19 participants with an age range of 1 to 20 months. Computed tomographic scans and three-dimensional photographs were both obtained on each child within 2 weeks of the clinical examination. Two analysts measured the anterior-posterior and biparietal distances on the digital images. Measures of reliability and bias between the modalities were calculated and compared.Caliper measurements were found to underestimate the anterior-posterior and biparietal distances as compared with those of the computed tomography and the three-dimensional photogrammetry (P < 0.001). Cranial index measurements between the computed tomography and the calipers differed by up to 6%. The difference between the 2 modalities was statistically significant (P = 0.021). The biparietal and cranial index results were similar between the digital modalities, but the anterior-posterior measurement was greater with the three-dimensional photogrammetry (P = 0.002). The coefficients of variation for repeated measures based on the computed tomography and the three-dimensional photogrammetry were 0.008 and 0.007, respectively.In conclusion, measurements based on digital modalities are generally reliable and interchangeable. Caliper measurements lead to underestimation of anterior-posterior and biparietal values compared with digital imaging.

Imaging of a parapharyngeal hemangiopericytoma. Radioimmunoscintigraphy (SPECT) with indium-111-labeled anti-CEA antibody, and comparison to digital subtraction angiography, computed tomography, and immunohistochemistry

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

Kairemo, K.J.; Hopsu, E.V.; Melartin, E.J.

1991-01-01

A 27-year-old male patient with a parapharyngeal hemangiopericytoma was investigated radiologically with orthopantomography, computed tomography, and digital subtraction angiography before the operation. Because a malignancy was suspected, the patient was imaged with gamma camera using radiolabeled monoclonal anticarcinoembryonal antigen antibody including single photon emission computed tomography. The radioantibody accumulated strongly into the neoplasm. Tumor to background ratio was 2.2. Samples of the excised tumor were stained immunohistochemically for desmin, vimentin, muscle actin, cytokeratin, CEA (carcinoembryonic antigen), and factor VIII. They showed that the antibody uptake was of unspecific nature and not due to CEA expression in the tumor.

Normal Variants and Pitfalls Encountered in PET Assessment of Gynecologic Malignancies.

PubMed

Yu, Jian Q; Doss, Mohan; Alpaugh, R Katherine

2018-04-01

Combined PET/computed tomography is used for oncological indications. PET/computed tomography benefits from the metabolic information of PET and the anatomic localization of computed tomography. The integrated scanner provides data with accurate registration of anatomy and molecular information. Many physiologic conditions, normal variants, and benign lesions within the pelvis and the body can cause confusion and uncertainty. False-negative results owing to low 18 F-fluorodeoxyglucose uptake from the tumor can produce diagnostic challenges and inaccurate conclusions. This article reviews normal variants and potential pitfalls encountered in PET assessment of gynecologic malignancies to provide useful information for the referring and reporting physicians. Copyright © 2017 Elsevier Inc. All rights reserved.

Computed Tomography and Thermography Increases CMC Material and Process Development Efficiency and Testing Effectiveness

NASA Technical Reports Server (NTRS)

Effinger, Michael; Beshears, Ron; Hufnagle, David; Walker, James; Russell, Sam; Stowell, Bob; Myers, David

2002-01-01

Nondestructive characterization techniques have been used to steer development and testing of CMCs. Computed tomography is used to determine the volumetric integrity of the CMC plates and components. Thermography is used to determine the near surface integrity of the CMC plates and components. For process and material development, information such as density uniformity, part delamination, and dimensional tolerance conformity is generated. The information from the thermography and computed tomography is correlated and then specimen cutting maps are superimposed on the thermography images. This enables for tighter data and potential explanation of off nominal test data. Examples of nondestructive characterization utilization to make decisions in process and material development and testing are presented.

UNSEDATED COMPUTED TOMOGRAPHY FOR DIAGNOSIS OF PELVIC CANAL OBSTRUCTION IN A LEOPARD GECKO (EUBLEPHARIS MACULARIUS).

PubMed

DeCourcy, Kelly; Hostnik, Eric T; Lorbach, Josh; Knoblaugh, Sue

2016-12-01

An adult leopard gecko ( Eublepharis macularius ) presented for lethargy, hyporexia, weight loss, decreased passage of waste, and a palpable caudal coelomic mass. Computed tomography showed a heterogeneous hyperattenuating (∼143 Hounsfield units) structure within the right caudal coelom. The distal colon-coprodeum lumen or urinary bladder was hypothesized as the most likely location for the heterogeneous structure. Medical support consisted of warm water and lubricant enema, as well as a heated environment. Medical intervention aided the passage of a plug comprised centrally of cholesterol and urates with peripheral stratified layers of fibrin, macrophages, heterophils, and bacteria. Within 24 hr, a follow-up computed tomography scan showed resolution of the pelvic canal plug.

Diffraction scattering computed tomography: a window into the structures of complex nanomaterials

PubMed Central

Birkbak, M. E.; Leemreize, H.; Frølich, S.; Stock, S. R.

2015-01-01

Modern functional nanomaterials and devices are increasingly composed of multiple phases arranged in three dimensions over several length scales. Therefore there is a pressing demand for improved methods for structural characterization of such complex materials. An excellent emerging technique that addresses this problem is diffraction/scattering computed tomography (DSCT). DSCT combines the merits of diffraction and/or small angle scattering with computed tomography to allow imaging the interior of materials based on the diffraction or small angle scattering signals. This allows, e.g., one to distinguish the distributions of polymorphs in complex mixtures. Here we review this technique and give examples of how it can shed light on modern nanoscale materials. PMID:26505175

Evaluation of dosimetry and image of very low-dose computed tomography attenuation correction for pediatric positron emission tomography/computed tomography: phantom study

NASA Astrophysics Data System (ADS)

Bahn, Y. K.; Park, H. H.; Lee, C. H.; Kim, H. S.; Lyu, K. Y.; Dong, K. R.; Chung, W. K.; Cho, J. H.

2014-04-01

In this study, phantom was used to evaluate attenuation correction computed tomography (CT) dose and image in case of pediatric positron emission tomography (PET)/CT scan. Three PET/CT scanners were used along with acryl phantom in the size for infant and ion-chamber dosimeter. The CT image acquisition conditions were changed from 10 to 20, 40, 80, 100 and 160 mA and from 80 to 100, 120 and 140 kVp, which aimed at evaluating penetrate dose and computed tomography dose indexvolume (CTDIvol) value. And NEMA PET Phantom™ was used to obtain PET image under the same CT conditions in order to evaluate each attenuation-corrected PET image based on standard uptake value (SUV) value and signal-to-noise ratio (SNR). In general, the penetrate dose was reduced by around 92% under the minimum CT conditions (80 kVp and 10 mA) with the decrease in CTDIvol value by around 88%, compared with the pediatric abdomen CT conditions (100 kVp and 100 mA). The PET image with its attenuation corrected according to each CT condition showed no change in SUV value and no influence on the SNR. In conclusion, if the minimum dose CT that is properly applied to body of pediatric patient is corrected for attenuation to ensure that the effective dose is reduced by around 90% or more compared with that for adult patient, this will be useful to reduce radiation exposure level.

Fusion Imaging: A Novel Staging Modality in Testis Cancer

PubMed Central

Sterbis, Joseph R.; Rice, Kevin R.; Javitt, Marcia C.; Schenkman, Noah S.; Brassell, Stephen A.

2010-01-01

Objective: Computed tomography and chest radiographs provide the standard imaging for staging, treatment, and surveillance of testicular germ cell neoplasms. Positron emission tomography has recently been utilized for staging, but is somewhat limited in its ability to provide anatomic localization. Fusion imaging combines the metabolic information provided by positron emission tomography with the anatomic precision of computed tomography. To the best of our knowledge, this represents the first study of the effectiveness using fusion imaging in evaluation of patients with testis cancer. Methods: A prospective study of 49 patients presenting to Walter Reed Army Medical Center with testicular cancer from 2003 to 2009 was performed. Fusion imaging was compared with conventional imaging, tumor markers, pathologic results, and clinical follow-up. Results: There were 14 true positives, 33 true negatives, 1 false positive, and 1 false negative. Sensitivity, specificity, positive predictive value, and negative predictive value were 93.3, 97.0, 93.3, and 97.0% respectively. In 11 patient scenarios, fusion imaging differed from conventional imaging. Utility was found in superior lesion detection compared to helical computed tomography due to anatomical/functional image co-registration, detection of micrometastasis in lymph nodes (pathologic nodes < 1cm), surveillance for recurrence post-chemotherapy, differentiating fibrosis from active disease in nodes < 2.5cm, and acting as a quality assurance measure to computed tomography alone. Conclusions: In addition to demonstrating a sensitivity and specificity comparable or superior to conventional imaging, fusion imaging shows promise in providing additive data that may assist in clinical decision-making. PMID:21103077

Fusion imaging: a novel staging modality in testis cancer.

PubMed

Sterbis, Joseph R; Rice, Kevin R; Javitt, Marcia C; Schenkman, Noah S; Brassell, Stephen A

2010-11-05

Computed tomography and chest radiographs provide the standard imaging for staging, treatment, and surveillance of testicular germ cell neoplasms. Positron emission tomography has recently been utilized for staging, but is somewhat limited in its ability to provide anatomic localization. Fusion imaging combines the metabolic information provided by positron emission tomography with the anatomic precision of computed tomography. To the best of our knowledge, this represents the first study of the effectiveness using fusion imaging in evaluation of patients with testis cancer. A prospective study of 49 patients presenting to Walter Reed Army Medical Center with testicular cancer from 2003 to 2009 was performed. Fusion imaging was compared with conventional imaging, tumor markers, pathologic results, and clinical follow-up. There were 14 true positives, 33 true negatives, 1 false positive, and 1 false negative. Sensitivity, specificity, positive predictive value, and negative predictive value were 93.3, 97.0, 93.3, and 97.0% respectively. In 11 patient scenarios, fusion imaging differed from conventional imaging. Utility was found in superior lesion detection compared to helical computed tomography due to anatomical/functional image co-registration, detection of micrometastasis in lymph nodes (pathologic nodes < 1cm), surveillance for recurrence post-chemotherapy, differentiating fibrosis from active disease in nodes < 2.5cm, and acting as a quality assurance measure to computed tomography alone. In addition to demonstrating a sensitivity and specificity comparable or superior to conventional imaging, fusion imaging shows promise in providing additive data that may assist in clinical decision-making.

Computational adaptive optics for broadband interferometric tomography of tissues and cells

NASA Astrophysics Data System (ADS)

Adie, Steven G.; Mulligan, Jeffrey A.

2016-03-01

Adaptive optics (AO) can shape aberrated optical wavefronts to physically restore the constructive interference needed for high-resolution imaging. With access to the complex optical field, however, many functions of optical hardware can be achieved computationally, including focusing and the compensation of optical aberrations to restore the constructive interference required for diffraction-limited imaging performance. Holography, which employs interferometric detection of the complex optical field, was developed based on this connection between hardware and computational image formation, although this link has only recently been exploited for 3D tomographic imaging in scattering biological tissues. This talk will present the underlying imaging science behind computational image formation with optical coherence tomography (OCT) -- a beam-scanned version of broadband digital holography. Analogous to hardware AO (HAO), we demonstrate computational adaptive optics (CAO) and optimization of the computed pupil correction in 'sensorless mode' (Zernike polynomial corrections with feedback from image metrics) or with the use of 'guide-stars' in the sample. We discuss the concept of an 'isotomic volume' as the volumetric extension of the 'isoplanatic patch' introduced in astronomical AO. Recent CAO results and ongoing work is highlighted to point to the potential biomedical impact of computed broadband interferometric tomography. We also discuss the advantages and disadvantages of HAO vs. CAO for the effective shaping of optical wavefronts, and highlight opportunities for hybrid approaches that synergistically combine the unique advantages of hardware and computational methods for rapid volumetric tomography with cellular resolution.

Cholecystokinin-Assisted Hydrodissection of the Gallbladder Fossa during FDG PET/CT-guided Liver Ablation

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

Tewari, Sanjit O., E-mail: tewaris@mskcc.org; Petre, Elena N., E-mail: petree@mskcc.org; Osborne, Joseph, E-mail: osbornej@mskcc.org

2013-12-15

A 68-year-old female with colorectal cancer developed a metachronous isolated fluorodeoxyglucose-avid (FDG-avid) segment 5/6 gallbladder fossa hepatic lesion and was referred for percutaneous ablation. Pre-procedure computed tomography (CT) images demonstrated a distended gallbladder abutting the segment 5/6 hepatic metastasis. In order to perform ablation with clear margins and avoid direct puncture and aspiration of the gallbladder, cholecystokinin was administered intravenously to stimulate gallbladder contraction before hydrodissection. Subsequently, the lesion was ablated successfully with sufficient margins, of greater than 1.0 cm, using microwave with ultrasound and FDG PET/CT guidance. The patient tolerated the procedure very well and was discharged home themore » next day.« less

Pseudoaneurysm of the articular branch of the descending genicular artery following double-bundle anterior cruciate ligament reconstruction.

PubMed

Tsubosaka, Masanori; Matsushita, Takehiko; Kuroda, Ryosuke; Matsumoto, Tomoyuki; Kurosaka, Masahiro

2017-09-01

This report describes a case of a pseudoaneurysm of the articular branch of the descending genicular artery following double-bundle anterior cruciate ligament (ACL) reconstruction. An 18-year-old male received double-bundle ACL reconstruction. During ACL reconstruction, a far anteromedial portal was created for femoral tunnel drilling. The patient presented with pulsatile swelling on the medial side of the knee on the second post-operative day. The pseudoaneurysm was diagnosed using contrast computed tomography and Doppler ultrasonography and was subsequently treated by embolization with a microcatheter. Although a vascular injury is a very rare complication of knee arthroscopy, it should be considered a possibility in patients who undergo such procedures. V.

Peritoneal mucinous cystadenocarcinoma of probable urachal origin: a challenging diagnosis

PubMed Central

Gore, D M; Bloch, S; Waller, W; Cohen, P

2006-01-01

This report describes the case of a mucinous cystadenocarcinoma of probable urachal origin that presented with mass effect, precipitating deep venous thrombosis and pulmonary embolism. The patient presented with acute symptoms of leg swelling, pain and dyspnoea, and a vague awareness of lower abdominal distension. Computer tomography showed a cystic mass closely related to the anterior abdominal wall and the superior aspect of the bladder. A 1500 cm3 cyst adherent to the dome of the urinary bladder was resected on laparotomy. Partial cystectomy was not carried out in the belief that the cyst represented a benign lesion. Subsequent imaging has shown cystic changes in the anterior bladder wall, and the patient has been referred for partial cystectomy. PMID:17021133

Successful treatment of growing basilar artery dissecting aneurysm by pipeline flow diversion embolization device.

PubMed

Gong, Dasen; Yan, Bernard; Dowling, Richard; Mitchell, Peter

2014-07-01

We describe a case of successful management of a growing basilar artery dissecting aneurysm by the Pipeline flow diversion embolization device (PED). A 48-year-old woman presented with severe headache, neck pain, and altered consciousness. Computed tomography showed subarachnoid hemorrhage located in basal cisterns, with a pontine infarct shown on magnetic resonance imaging. Digital subtraction angiography showed dissecting aneurysm of the trunk of the basilar artery, with growth over time on repeated imaging. Repeated imaging demonstrated growth in size of the aneurysm. The aneurysm was treated with PED with complete obliteration of the basilar artery aneurysm. Subsequent follow-up demonstrated good clinical recovery. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Infected Congenital Epicardial Cyst Presenting as Acute Abdomen.

PubMed

Dribin, Timothy; Files, Matthew D; Rudzinski, Erin R; Kaplan, Ron; Stone, Kimberly P

2016-12-01

A previously healthy 3-year-old boy presented to the emergency department with abdominal pain, fever, and emesis. Laboratory and radiologic evaluation for causes of acute abdomen were negative; however, review of the abdominal x-ray demonstrated cardiomegaly with the subsequent diagnosis of pericardial cyst by echocardiogram and computed tomography. The patient underwent surgical decompression and attempted removal of the cystic structure revealing that the cyst originated from the epicardium. His abdominal pain and fever resolved postoperatively and he completed a 3-week course of ceftriaxone for treatment of Propionibacterium acnes infected congenital epicardial cyst. Emergency department physicians must maintain a broad differential in patients with symptoms of acute abdomen to prevent complications from serious cardiac or pulmonary diseases that present with symptoms of referred abdominal pain.

Airway obstruction due to tracheomalacia caused by innominate artery compression and a kyphotic cervical spine.

PubMed

Liu, Chia-Hsin; Huang, Wen-Sheng; Wang, Hong-Hau; Wu, Chin-Pyng; Chian, Chih-Feng; Perng, Wann-Cherng; Tsai, Chen-Liang

2015-02-01

Tracheomalacia can cause variable degrees of intrathoracic airway obstruction and is an easily overlooked cause of respiratory distress in adults. Here, we report a case of acute respiratory failure in which subglottic stenosis was accidentally identified during endotracheal intubation. Subsequent bronchoscopy and computed tomography of the thorax and neck revealed tracheal compression with tracheomalacia caused by a tortuous innominate artery and a kyphotic cervical spine. The patient underwent rigid bronchoscopy with metal stent implantation, and her symptoms were alleviated. These findings outline the importance of precise diagnosis and interventions for preventing recurrent life-threatening respiratory failure in such cases. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Radiographic patterns in the diagnostic approach to organizing pneumonia.

PubMed

Utrilla Contreras, C; Fernández-Velilla Peña, M; García Río, F; Torres Sánchez, M I

2014-01-01

A 56-year-old woman, non-smoker, who complained of dry cough and dyspnea during the last month came to the emergency department due to increased dyspnea. The chest X-ray showed areas of poorly defined, bilateral alveolar opacities, leading to the diagnosis of bronchopneumonia with partial respiratory failure. During admission, she experienced an exacerbation of the dyspnea. A high-resolution computed tomography scan was performed, showing areas of ground glass opacities with interlobular septal thickening ("crazy-paving" pattern), predominantly in lower lobes. She required mechanical ventilation and she was admitted to the intensive care unit. Subsequently, an open lung biopsy was performed. The following questions should be proposed: Copyright © 2013 Elsevier España, S.L. All rights reserved.

Positron Emission Tomography/Computed Tomography Assessment After Immunochemotherapy and Irradiation Using the Lugano Classification Criteria in the IELSG-26 Study of Primary Mediastinal B-Cell Lymphoma

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

Ceriani, Luca, E-mail: luca.ceriani@eoc.ch; Martelli, Maurizio; Gospodarowicz, Maria K.

Purpose: To assess the predictive value of {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) for disease recurrence after immunochemotherapy (R-CHT) and mediastinal irradiation (RT), using the recently published criteria of the Lugano classification to predict outcomes for patients with primary mediastinal large B-cell lymphoma. Methods and Materials: Among 125 patients prospectively enrolled in the IELSG-26 study, 88 were eligible for central review of PET/CT scans after completion of RT. Responses were evaluated using the 5-point Deauville scale at the end of induction R-CHT and after consolidation RT. According to the Lugano classification, a complete metabolic response (CMR) was defined bymore » a Deauville score (DS) ≤3. Results: The CMR (DS1, -2, or -3) rate increased from 74% (65 patients) after R-CHT to 89% (78 patients) after consolidation RT. Among the 10 patients (11%) with persistently positive scans, the residual uptake after RT was slightly higher than the liver uptake in 6 patients (DS4; 7%) and markedly higher in 4 patients (DS5; 4%): these patients had a significantly poorer 5-year progression-free survival and overall survival. At a median follow-up of 60 months (range, 35-107 months), no patients with a CMR after RT have relapsed. Among the 10 patients who did not reach a CMR, 3 of the 4 patients (positive predictive value, 75%) with DS5 after RT had subsequent disease progression (within the RT volume in all cases) and died. All patients with DS4 had good outcomes without recurrence. Conclusions: All the patients obtaining a CMR defined as DS ≤3 remained progression-free at 5 years, confirming the excellent negative predictive value of the Lugano classification criteria in primary mediastinal large B-cell lymphoma patients. The few patients with DS4 also had an excellent outcome, suggesting that they do not necessarily require additional therapy, because the residual {sup 18}F-fluorodeoxyglucose uptake may not reflect persistent lymphoma.« less

Role of computed tomography and [18F] fluorodeoxyglucose positron emission tomography image fusion in conformal radiotherapy of non-small cell lung cancer: a comparison with standard techniques with and without elective nodal irradiation.

PubMed

Ceresoli, Giovanni Luca; Cattaneo, Giovanni Mauro; Castellone, Pietro; Rizzos, Giovanna; Landoni, Claudio; Gregorc, Vanesa; Calandrino, Riccardo; Villa, Eugenio; Messa, Cristina; Santoro, Armando; Fazio, Ferruccio

2007-01-01

Mediastinal elective node irradiation (ENI) in patients with non-small cell lung cancer candidate to radical radiotherapy is controversial. In this study, the impact of co-registered [18F]fluorodeoxyglucose-positron emission tomography (PET) and standard computed tomography (CT) on definition of target volumes and toxicity parameters was evaluated, by comparison with standard CT-based simulation with and without ENI. CT-based gross tumor volume (GTVCT) was first contoured by a single observer without knowledge of PET results. Subsequently, the integrated GTV based on PET/CT coregistered images (GTVPET/CT) was defined. Each patient was planned according to three different treatment techniques: 1) radiotherapy with ENI using the CT data set alone (ENI plan); 2) radiotherapy without ENI using the CT data set alone (no ENI plan); 3) radiotherapy without ENI using PET/CT fusion data set (PET plan). Rival plans were compared for each patient with respect to dose to the normal tissues (spinal cord, healthy lungs, heart and esophagus). The addition of PET-modified TNM staging in 10/21 enrolled patients (48%); 3/21 were shifted to palliative treatment due to detection of metastatic disease or large tumor not amenable to high-dose radiotherapy. In 7/18 (39%) patients treated with radical radiotherapy, a significant (> or =25%) change in volume between GTVCT and GTVPET/CT was observed. For all the organs at risk, ENI plans had dose values significantly greater than no-ENI and PET plans. Comparing no ENI and PET plans, no statistically significant difference was observed, except for maximum point dose to the spinal cord Dmax, which was significantly lower in PET plans. Notably, even in patients in whom PET/CT planning resulted in an increased GTV, toxicity parameters were fairly acceptable, and always more favorable than with ENI plans. Our study suggests that [18F]-fluorodeoxyglucose-PET should be integrated in no-ENI techniques, as it improves target volume delineation without a major increase in predicted toxicity.

Asymptomatic Emphysematous Pyelonephritis - Positron Emission Tomography Computerized Tomography Aided Diagnostic and Therapeutic Elucidation

PubMed Central

Pathapati, Deepti; Shinkar, Pawan Gulabrao; kumar, Satya Awadhesh; Jha; Dattatreya, Palanki Satya; Chigurupati, Namrata; Chigurupati, Mohana Vamsy; Rao, Vatturi Venkata Satya Prabhakar

2017-01-01

The authors report an interesting coincidental unearthing by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) of a potentially serious medical condition of emphysematous pyelonephritis in a case of nasopharyngeal carcinoma. The management by conservative ureteric stenting and antibiotics was done with gratifying clinical outcome. PMID:28242985

[Multispiral computed tomographic semiotics of laryngeal cancer].

PubMed

Vasil'ev, P V; Iudin, A L; Sdvizhkov, A M; Kozhanov, L G

2007-01-01

Multispiral computed tomography (MSCT) with intravenous bolus contrasting is a currently available method for radiodiagnosis of laryngeal cancer. MSCT is of much higher informative value in estimating the extent of a tumorous lesion than the traditional radiodiagnostic techniques: linear tomography, lateral X-ray study, roentgenoscopy and roentgenography of the laryngopharynx and esophagus with barium meal.

Diffuse cylindrical bronchiectasis due to eosinophilic bronchopneumopathy in a dog

PubMed Central

Meler, Erika; Pressler, Barrak M.; Heng, Hock Gan; Baird, Debra K.

2010-01-01

A miniature pinscher-cross was evaluated for chronic coughing. Computed tomography and bronchoscopy revealed severe, diffuse, cylindrical bronchiectasis secondary to eosinophilic bronchopneumopathy. Computed tomography is the gold standard for diagnosis of bronchiectasis in humans, and should be further investigated in dogs as a means of characterizing severity and pattern of disease. PMID:20885829

Abernethy malformation with portal vein aneurysm in a child.

PubMed

Chandrashekhara, Sheragaru H; Bhalla, Ashu Seith; Gupta, Arun Kumar; Vikash, C S; Kabra, Susheel Kumar

2011-01-01

Abernethy malformation is an extremely rare anomaly of the splanchnic venous system. We describe multidetector computed tomography findings of an incidentally detected Abernethy malformation with portal vein aneurysm in a two-and-half-year old child. The computed tomography scan was performed for the evaluation of respiratory distress, poor growth, and loss of appetite.

Computed tomography guided localization of clinically occult breast carcinoma-the ''N'' skin guide

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

Kopans, D.B.; Meyer, J.E.

1982-10-01

Standard computed tomography (CT) can be used for the three-dimensional localization of clinically occult suspicious breast lesions whose exact position cannot be determined by standard mammographic views. A method is described that facilitates accurate preoperative needle localization using CT guidance, once the position of these lesions is defined.

Presence of gas in left ventricle due to infective endocarditis.

PubMed

Laiq, Zenab; Yarmohammadi, Hirad; Nabeel, Yassar; Adatya, Sirtaz

2016-01-01

Gas in myocardium is a rare manifestation of infective endocarditis caused by gas producing bacteria. We present a case of infective endocarditis caused by Citrobacter Koseri initially diagnosed by computed tomography and confirmed with transesophageal echocardiogram. Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

Use of Computed Tomography Imaging for Qualifying Coarse Roots, Rhizomes, Peat, and Particle Densities in Marsh Soils

EPA Science Inventory

Computed tomography (CT) imaging has been used to describe and quantify subtidal, benthic animals such as polychaetes, amphipods, and shrimp. Here, for the first time, CT imaging is used to successfully quantify wet mass of coarse roots, rhizomes, and peat in cores collected from...

Use of Computer-Aided Tomography (CT) Imaging for Quantifying Coarse Roots, Rhizomes, Peat, and Particle Densities in Marsh Soils

EPA Science Inventory

Computer-aided Tomography (CT) imaging was utilized to quantify wet mass of coarse roots, rhizomes, and peat in cores collected from organic-rich (Jamaica Bay, NY) and mineral (North Inlet, SC) Spartina alterniflora soils. Calibration rods composed of materials with standard dens...

APPLICATION OF COMPUTER-AIDED TOMOGRAPHY TO VISUALIZE AND QUANTIFY BIOGENIC STRUCTURES IN MARINE SEDIMENTS

EPA Science Inventory

We used computer-aided tomography (CT) for 3D visualization and 2D analysis of

marine sediment cores from 3 stations (at 10, 75 and 118 m depths) with different environmental

impact. Biogenic structures such as tubes and burrows were quantified and compared among st...

Micro-computed tomography of pupal metamorphosis in the solitary bee Megachile rotundata

USDA-ARS?s Scientific Manuscript database

Insect metamorphosis involves a complex change in form and function, but most of these changes are internal and treated as a black box. In this study, we examined development of the solitary bee, Megachile rotundata, using micro-computed tomography (µCT) and digital volume analysis. We describe deve...

Reliability of voxel gray values in cone beam computed tomography for preoperative implant planning assessment.

PubMed

Parsa, Azin; Ibrahim, Norliza; Hassan, Bassam; Motroni, Alessandro; van der Stelt, Paul; Wismeijer, Daniel

2012-01-01

To assess the reliability of cone beam computed tomography (CBCT) voxel gray value measurements using Hounsfield units (HU) derived from multislice computed tomography (MSCT) as a clinical reference (gold standard). Ten partially edentulous human mandibular cadavers were scanned by two types of computed tomography (CT) modalities: multislice CT and cone beam CT. On MSCT scans, eight regions of interest (ROI) designating the site for preoperative implant placement were selected in each mandible. The datasets from both CT systems were matched using a three-dimensional (3D) registration algorithm. The mean voxel gray values of the region around the implant sites were compared between MSCT and CBCT. Significant differences between the mean gray values obtained by CBCT and HU by MSCT were found. In all the selected ROIs, CBCT showed higher mean values than MSCT. A strong correlation (R=0.968) between mean voxel gray values of CBCT and mean HU of MSCT was determined. Voxel gray values from CBCT deviate from actual HU units. However, a strong linear correlation exists, which may permit deriving actual HU units from CBCT using linear regression models.

Inflammatory Pseudotumor-Like Follicular Dendritic Cell Sarcoma of the Spleen: Computed Tomography Imaging Characteristics in 5 Patients.

PubMed

Li, Xiumei; Shi, Zhenshan; You, Ruixiong; Li, Yueming; Cao, Dairong; Lin, Renjie; Huang, Xinming

The purpose of this study was to retrospectively review the computed tomography (CT) and clinicopathological characteristics of inflammatory pseudotumor (IPT)-like follicular dendritic cell sarcoma (FDCS) of the spleen in 5 patients. Clinical, pathologic, and CT imaging findings of 5 patients with IPT-like FDCS of the spleen were reviewed and analyzed. Computed tomography imaging and pathologic features were compared. Abdominal unenhanced CT revealed a well-defined hypodense mass in the spleen with complex internal architecture with focal necrosis and/or speckle-strip calcification. On postcontrast CT, slightly delayed enhancement was observed in 5 cases. Four patients had a normalized spleen. The fourth patient had lung metastasis. The fifth patient had 2 relatively small lesions as well as metastases to the spine. Computed tomography imaging features of IPT-like FDCS of the spleen are distinctly different from other hypovascular splenic neoplasm; however, the definitive diagnosis requires further confirmation with needle biopsy or surgery. Inflammatory pseudotumor-like FDCS of the spleen should be suggested by using the CT imaging features of the splenic mass with evidence of metastatic disease.

Malignant head and neck tumours in Radiology Department JPMC Karachi -- a tertiary care experience.

PubMed

Kadri, Shazia; Uddin, Sami; Ahmed, Naveed; Mahmood, Tariq

2015-08-01

To study age, gender and sites of malignant head and neck tumours on contrast-enhanced computed tomography and to elucidate its role. The retrospective study was conducted at the Jinnah Postgraduate Medical Centre, Karachi, and comprised data of patients with histologically proven malignant head and neck tumours reporting from February 2013 to February 2014. Contrast enhanced computed tomography with puffed cheek technique was done in cases of oral cancer, while routine contrast computed tomography was done in cases of other head and neck tumours. SPSS 19 was used for statistical analysis. A total of 100 biopsy-proven cases of malignant tumours comprised the study sample. The male: female ratio was 1.5:1 with an overall mean age of 46.4±16-76 years. . The most common histopathologically proven tumour was squamous cell carcinoma affecting oral mucosa 43(43%), followed by larynx 27(27%) and pharynx 10(10%) . Oral squamous cell carcinoma was the commonest tumour. Compute tomography scan with puffed cheek technique played a beneficial role in locating the site of primary tumour.

Imaging of the midpalatal suture in a porcine model: flat-panel volume computed tomography compared with multislice computed tomography.

PubMed

Hahn, Wolfram; Fricke-Zech, Susanne; Fialka-Fricke, Julia; Dullin, Christian; Zapf, Antonia; Gruber, Rudolf; Sennhenn-kirchner, Sabine; Kubein-Meesenburg, Dietmar; Sadat-Khonsari, Reza

2009-09-01

An investigation was conducted to compare the image quality of prototype flat-panel volume computed tomography (fpVCT) and multislice computed tomography (MSCT) of suture structures. Bone samples were taken from the midpalatal suture of 5 young (16 weeks) and 5 old (200 weeks) Sus scrofa domestica and fixed in formalin solution. An fpVCT prototype and an MSCT were used to obtain images of the specimens. The facial reformations were assessed by 4 observers using a 1 (excellent) to 5 (poor) rating scale for the weighted criteria visualization of the suture structure. A linear mixed model was used for statistical analysis. Results with P < .05 were considered to be statistically significant. The visualization of the suture of young specimens was significantly better than that of older animals (P < .001). The visualization of the suture with fpVCT was significantly better than that with MSCT (P < .001). Compared with MSCT, fpVCT produces superior results in the visualization of the midpalatal suture in a Sus scrofa domestica model.

Spectrally resolving and scattering-compensated x-ray luminescence/fluorescence computed tomography

PubMed Central

Cong, Wenxiang; Shen, Haiou; Wang, Ge

2011-01-01

The nanophosphors, or other similar materials, emit near-infrared (NIR) light upon x-ray excitation. They were designed as optical probes for in vivo visualization and analysis of molecular and cellular targets, pathways, and responses. Based on the previous work on x-ray fluorescence computed tomography (XFCT) and x-ray luminescence computed tomography (XLCT), here we propose a spectrally-resolving and scattering-compensated x-ray luminescence/fluorescence computed tomography (SXLCT or SXFCT) approach to quantify a spatial distribution of nanophosphors (other similar materials or chemical elements) within a biological object. In this paper, the x-ray scattering is taken into account in the reconstruction algorithm. The NIR scattering is described in the diffusion approximation model. Then, x-ray excitations are applied with different spectra, and NIR signals are measured in a spectrally resolving fashion. Finally, a linear relationship is established between the nanophosphor distribution and measured NIR data using the finite element method and inverted using the compressive sensing technique. The numerical simulation results demonstrate the feasibility and merits of the proposed approach. PMID:21721815

Radiolabeling, whole-body single photon emission computed tomography/computed tomography imaging, and pharmacokinetics of carbon nanohorns in mice

PubMed Central

Zhang, Minfang; Jasim, Dhifaf A; Ménard-Moyon, Cécilia; Nunes, Antonio; Iijima, Sumio; Bianco, Alberto; Yudasaka, Masako; Kostarelos, Kostas

2016-01-01

In this work, we report that the biodistribution and excretion of carbon nanohorns (CNHs) in mice are dependent on their size and functionalization. Small-sized CNHs (30–50 nm; S-CNHs) and large-sized CNHs (80–100 nm; L-CNHs) were chemically functionalized and radiolabeled with [111In]-diethylenetriaminepentaacetic acid and intravenously injected into mice. Their tissue distribution profiles at different time points were determined by single photon emission computed tomography/computed tomography. The results showed that the S-CNHs circulated longer in blood, while the L-CNHs accumulated faster in major organs like the liver and spleen. Small amounts of S-CNHs- and L-CNHs were excreted in urine within the first few hours postinjection, followed by excretion of smaller quantities within the next 48 hours in both urine and feces. The kinetics of excretion for S-CNHs were more rapid than for L-CNHs. Both S-CNH and L-CNH material accumulated mainly in the liver and spleen; however, S-CNH accumulation in the spleen was more prominent than in the liver. PMID:27524892

Clinical and Radiographic Response of Extramedullary Leukemia in Patients Treated With Gemtuzumab Ozogamicin.

PubMed

McNeil, Michael J; Parisi, Marguerite T; Hijiya, Nobuko; Meshinchi, Soheil; Cooper, Todd; Tarlock, Katherine

2018-05-04

Extramedullary leukemia (EML) is common in pediatric acute leukemia and can present at diagnosis or relapse. CD33 is detected on the surface of myeloid blasts in many patients with acute myelogenous leukemia and is the target of the antibody drug conjugate gemtuzumab ozogamicin (GO). Here we present 2 patients with CD33 EML treated with GO. They achieved significant response, with reduction of EML on both clinical and radiographic exams, specifically fluorine fluorodeoxyglucose positron emission tomography/computed tomography, demonstrating potential for targeted therapy with GO as a means of treating EML in patients with CD33 leukemia and the utility of fluorine fluorodeoxyglucose positron emission tomography/computed tomography monitoring in EML.

68Gallium-Arginine-Glycine-Aspartic Acid and 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Chondroblastic Osteosarcoma of the Skull.

PubMed

Orunmuyi, Akintunde; Modiselle, Moshe; Lengana, Thabo; Ebenhan, Thomas; Vorster, Mariza; Sathekge, Mike

2017-09-01

We report the case of a 32 year-old male with Chondroblastic Osteosarcoma of the skull, which was imaged with both 18 [F]fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) and 68 Gallium-arginine-glycine-aspartic acid ( 68 Ga-RGD) PET/CT. The 18 F-FDG PET/CT did not demonstrate the tumour, whereas the 68 Ga-RGD PET/CT clearly depicted a left-sided frontal tumour. 68 Ga-RGD PET/CT may be a clinically useful imaging modality for early detection of recurrent osteosarcoma, considering the limitations of 18 F-FDG PET in a setting of low glycolytic activity.

Nonmetastatic Castration-resistant Prostate Cancer: A Modern Perspective.

PubMed

Cancian, Madeline; Renzulli, Joseph F

2018-06-01

Nonmetastatic castration-resistant prostate cancer (nmCRPC) presents a challenge to urologists as currently there are no Food and Drug Administration-approved therapies. However, there are new imaging modalities, including fluciclovine positron emission tomography-computed tomography and Ga-PSMA (prostate specific membrane antigent) positron emission tomography-computed tomography, which are improving accuracy of diagnosis. With improved imaging, we are better able to target therapy. Today there are 3 ongoing clinical trials studying second-generation antiandrogens in nmCRPC, which hold the promise of a new treatment paradigm. In this article, we will review the new imaging techniques and the rationale behind novel treatment modalities in nmCRPC. Copyright © 2018 Elsevier Inc. All rights reserved.

Optimization of a Solid-State Electron Spin Qubit Using Gate Set Tomography (Open Access, Publisher’s Version)

DTIC Science & Technology

2016-10-13

enielse@sandia.gov and a.morello@unsw.edu.au Keywords: quantum computing , silicon, tomography Supplementarymaterial for this article is available online...Abstract State of the art qubit systems are reaching the gatefidelities required for scalable quantum computation architectures. Further improvements in...and addressedwhen the qubit is usedwithin a fault-tolerant quantum computation scheme. 1. Introduction One of themain challenges in the physical

Adaptive-optics optical coherence tomography processing using a graphics processing unit.

PubMed

Shafer, Brandon A; Kriske, Jeffery E; Kocaoglu, Omer P; Turner, Timothy L; Liu, Zhuolin; Lee, John Jaehwan; Miller, Donald T

2014-01-01

Graphics processing units are increasingly being used for scientific computing for their powerful parallel processing abilities, and moderate price compared to super computers and computing grids. In this paper we have used a general purpose graphics processing unit to process adaptive-optics optical coherence tomography (AOOCT) images in real time. Increasing the processing speed of AOOCT is an essential step in moving the super high resolution technology closer to clinical viability.

High-Resolution Computed Tomography and Pulmonary Function Findings of Occupational Arsenic Exposure in Workers.

PubMed

Ergün, Recai; Evcik, Ender; Ergün, Dilek; Ergan, Begüm; Özkan, Esin; Gündüz, Özge

2017-05-05

The number of studies where non-malignant pulmonary diseases are evaluated after occupational arsenic exposure is very few. To investigate the effects of occupational arsenic exposure on the lung by high-resolution computed tomography and pulmonary function tests. Retrospective cross-sectional study. In this study, 256 workers with suspected respiratory occupational arsenic exposure were included, with an average age of 32.9±7.8 years and an average of 3.5±2.7 working years. Hair and urinary arsenic levels were analysed. High-resolution computed tomography and pulmonary function tests were done. In workers with occupational arsenic exposure, high-resolution computed tomography showed 18.8% pulmonary involvement. In pulmonary involvement, pulmonary nodule was the most frequently seen lesion (64.5%). The other findings of pulmonary involvement were 18.8% diffuse interstitial lung disease, 12.5% bronchiectasis, and 27.1% bullae-emphysema. The mean age of patients with pulmonary involvement was higher and as they smoked more. The pulmonary involvement was 5.2 times higher in patients with skin lesions because of arsenic. Diffusing capacity of lung for carbon monoxide was significantly lower in patients with pulmonary involvement. Besides lung cancer, chronic occupational inhalation of arsenic exposure may cause non-malignant pulmonary findings such as bronchiectasis, pulmonary nodules and diffuse interstitial lung disease. So, in order to detect pulmonary involvement in the early stages, workers who experience occupational arsenic exposure should be followed by diffusion test and high-resolution computed tomography.

The Influence of Reconstruction Kernel on Bone Mineral and Strength Estimates Using Quantitative Computed Tomography and Finite Element Analysis.

PubMed

Michalski, Andrew S; Edwards, W Brent; Boyd, Steven K

2017-10-17

Quantitative computed tomography has been posed as an alternative imaging modality to investigate osteoporosis. We examined the influence of computed tomography convolution back-projection reconstruction kernels on the analysis of bone quantity and estimated mechanical properties in the proximal femur. Eighteen computed tomography scans of the proximal femur were reconstructed using both a standard smoothing reconstruction kernel and a bone-sharpening reconstruction kernel. Following phantom-based density calibration, we calculated typical bone quantity outcomes of integral volumetric bone mineral density, bone volume, and bone mineral content. Additionally, we performed finite element analysis in a standard sideways fall on the hip loading configuration. Significant differences for all outcome measures, except integral bone volume, were observed between the 2 reconstruction kernels. Volumetric bone mineral density measured using images reconstructed by the standard kernel was significantly lower (6.7%, p < 0.001) when compared with images reconstructed using the bone-sharpening kernel. Furthermore, the whole-bone stiffness and the failure load measured in images reconstructed by the standard kernel were significantly lower (16.5%, p < 0.001, and 18.2%, p < 0.001, respectively) when compared with the image reconstructed by the bone-sharpening kernel. These data suggest that for future quantitative computed tomography studies, a standardized reconstruction kernel will maximize reproducibility, independent of the use of a quantitative calibration phantom. Copyright © 2017 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

Assessment of cardiovascular risk profile based on measurement of tophus volume in patients with gout.

PubMed

Lee, Kyung-Ann; Ryu, Se-Ri; Park, Seong-Jun; Kim, Hae-Rim; Lee, Sang-Heon

2018-05-01

Hyperuricemia and gout are associated with increased risk of cardiovascular disease and metabolic syndrome. The aim of this study was to evaluate the correlation of total tophus volumes, measured using dual-energy computed tomography, with cardiovascular risk and the presence of metabolic syndrome. Dual-energy computed tomography datasets from 91 patients with a diagnosis of gout were analyzed retrospectively. Patients who received urate lowering therapy were excluded to avoid the effect on tophus volume. The total volumes of tophaceous deposition were quantified using automated volume assessment software. The 10-year cardiovascular risk using the Framingham Risk Score and metabolic syndrome based on the Third Adult Treatment Panel criteria were estimated. Fifty-five and 36 patients with positive and negative dual-energy computed tomography results, respectively, were assessed. Patients with positive dual-energy computed tomography results showed significantly higher systolic blood pressure, diastolic blood pressure, fasting glucose, and higher prevalence of chronic kidney disease, compared with those with negative dual-energy computed tomography results. The total tophus volumes were significantly correlated with the Framingham Risk Score, and the number of metabolic syndrome components (r = 0.22 and p = 0.036 and r = 0.373 and p < 0.001, respectively). The total tophus volume was one of the independent prognostic factors for the Framingham Risk Score in a multivariate analysis. This study showed the correlation of total tophus volumes with cardiovascular risk and metabolic syndrome-related comorbidities. A high urate burden could affect unfavorable cardiovascular profiles.

Comparison of Diagnostic Accuracy of Radiation Dose-Equivalent Radiography, Multidetector Computed Tomography and Cone Beam Computed Tomography for Fractures of Adult Cadaveric Wrists

PubMed Central

Neubauer, Jakob; Benndorf, Matthias; Reidelbach, Carolin; Krauß, Tobias; Lampert, Florian; Zajonc, Horst; Kotter, Elmar; Langer, Mathias; Fiebich, Martin; Goerke, Sebastian M.

2016-01-01

Purpose To compare the diagnostic accuracy of radiography, to radiography equivalent dose multidetector computed tomography (RED-MDCT) and to radiography equivalent dose cone beam computed tomography (RED-CBCT) for wrist fractures. Methods As study subjects we obtained 10 cadaveric human hands from body donors. Distal radius, distal ulna and carpal bones (n = 100) were artificially fractured in random order in a controlled experimental setting. We performed radiation dose equivalent radiography (settings as in standard clinical care), RED-MDCT in a 320 row MDCT with single shot mode and RED-CBCT in a device dedicated to musculoskeletal imaging. Three raters independently evaluated the resulting images for fractures and the level of confidence for each finding. Gold standard was evaluated by consensus reading of a high-dose MDCT. Results Pooled sensitivity was higher in RED-MDCT with 0.89 and RED-MDCT with 0.81 compared to radiography with 0.54 (P = < .004). No significant differences were detected concerning the modalities’ specificities (with values between P = .98). Raters' confidence was higher in RED-MDCT and RED-CBCT compared to radiography (P < .001). Conclusion The diagnostic accuracy of RED-MDCT and RED-CBCT for wrist fractures proved to be similar and in some parts even higher compared to radiography. Readers are more confident in their reporting with the cross sectional modalities. Dose equivalent cross sectional computed tomography of the wrist could replace plain radiography for fracture diagnosis in the long run. PMID:27788215

Single photon emission computed tomography and oth selected computer topics

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

Frey, G.D.

1981-07-01

This book, the proceedings of a meeting in January 1980, contains 21 papers. Thirteen are devoted to aspects of emission tomography, four to nuclear cardiology, and five to other topics. The initial set of papers consists of reviews of the single photon emission tomography process. These include transverse axial tomography using scintillation cameras and other devices, longitudinal section tomography, and pin-hole and slant-hole systems. These reviews are generally well done, but as might be expected, lack any coherence from paper to paper. The papers on nuclear cardiology include several of Fourier analysis in nuclear cardiology and one on shunt quantification.more » Other clinical papers are on quantifying Tc-99m glucoheptonate uptake in the brain and on iron-59 retention studies. A general criticism of the book is the poor quality of photographic reproductions.« less

Exponentially Decelerated Contrast Media Injection Rate Combined With a Novel Patient-Specific Contrast Formula Reduces Contrast Volume Administration and Radiation Dose During Computed Tomography Pulmonary Angiography.

PubMed

Saade, Charbel; Mayat, Ahmad; El-Merhi, Fadi

2016-01-01

Matching contrast injection timing with vessel dynamics significantly improves vessel opacification and reduces contrast dose in the assessment of pulmonary embolism during computed tomography (CT) pulmonary angiography. The aim of this study was to investigate opacification of the pulmonary vasculature (PV) during CT pulmonary angiography using a patient-specific contrast formula (PSCF) and exponentially decelerated contrast media (EDCM) injection rate. Institutional review board approved this retrospective study. Computed tomography pulmonary angiography was performed on 200 patients with suspected pulmonary embolism using a 64-channel CT scanner. Patient demographics were equally distributed. Patients were randomly assigned to 2 equal protocol groups: protocol A used a PSCF, and protocol B involved the use of a PSCF combined with EDCM. The mean cross-sectional opacification profile of 8 central and 11 peripheral PVs were measured for each patient, and arteriovenous contrast ratio was calculated. Protocols were compared using Mann-Whitney U nonparametric statistics. Jackknife alternative free-response receiver operating characteristic analyses were used to assess diagnostic efficacy. Interobserver variations were investigated using kappa methods. A number of pulmonary arteries demonstrated increases in opacification (P < 0.02) for protocol B compared with A, whereas opacification in all veins was reduced in protocol B (P < 0.03). Subsequently, increased arteriovenous contrast ratio in protocol B compared with A was observed at all anatomic locations (P < 0.0002). An increase in jackknife alternative free-response receiver operating characteristic figure of merit (P < 0.0002) and interobserver variation was observed with protocol B compared with protocol A (κ = 0.3-0.73). Mean contrast volume was reduced in protocol B (29 [4] mL) compared with protocol A (33 [9] mL). Mean effective radiation dose in protocol B (1.2 [0.4] mSv) was reduced by 14% compared with protocol A (1.4 [0.6] mSv). Significant improvements in visualization of the PV can be achieved with a low contrast volume using an EDCM and PSCF. The reduced risk of cancer induction is highlighted.

Triamcinolone acetonide activates an anti-inflammatory and folate receptor-positive macrophage that prevents osteophytosis in vivo.

PubMed

Siebelt, Michiel; Korthagen, Nicoline; Wei, Wu; Groen, Harald; Bastiaansen-Jenniskens, Yvonne; Müller, Christina; Waarsing, Jan Hendrik; de Jong, Marion; Weinans, Harrie

2015-12-05

Triamcinolone acetonide (TA) is used for osteoarthritis management to reduce pain, and pre-clinical studies have shown that TA limits osteophyte formation. Osteophyte formation is known to be facilitated by synovial macrophage activation. TA injections might influence macrophage activation and subsequently reduce osteophytosis. Although widely applied in clinical care, the mechanism through which TA exerts this effect remains unknown. In this animal study, we investigated the in vivo effects of TA injections on macrophage activation, osteophyte development and joint degeneration. Furthermore, in vitro macrophage differentiation experiments were conducted to further explain working mechanisms of TA effects found in vivo. Osteoarthritis was induced in rat knees using papain injections and a running protocol. Untreated and TA-treated animals were longitudinally monitored for 12 weeks with in vivo micro-computed tomography (μCT) to measure subchondral bone changes. Synovial macrophage activation was measured in vivo using folate receptor β (FRβ)-targeted single-photon emission computed tomography/computed tomography. Articular cartilage was analyzed at 6 and 12 weeks with ex vivo contrast-enhanced μCT and histology. To further explain the outcomes of our in vivo study, TA on macrophages was also studied in vitro. These cultured macrophages were either M1- or M2-activated, and they were analyzed using fluorescence-activated cell sorting for CD163 and FRβ expression as well as for messenger RNA (mRNA) expression of interleukin (IL)-10. Our in vivo study showed that intra-articular injections with TA strongly enhanced FRβ(+) macrophage activation. Despite stimulated macrophage activation, osteophyte formation was fully prevented. There was no beneficial effect of TA against cartilage degradation or subchondral bone sclerosis. In vitro macrophage cultures showed that TA strongly induced monocyte differentiation towards CD163(+) and FRβ(+) macrophages. Furthermore, TA-stimulated M2 macrophages showed enhanced IL-10 expression at the mRNA level. TA injections potently induce a CD163(+)- and FRβ(+)-activated macrophage with anti-inflammatory characteristics such as reduced IL-10 production in vitro and lack of osteophytosis in vivo.

Evaluation of pulmonary function using breathing chest radiography with a dynamic flat panel detector: primary results in pulmonary diseases.

PubMed

Tanaka, Rie; Sanada, Shigeru; Okazaki, Nobuo; Kobayashi, Takeshi; Fujimura, Masaki; Yasui, Masahide; Matsui, Takeshi; Nakayama, Kazuya; Nanbu, Yuko; Matsui, Osamu

2006-10-01

Dynamic flat panel detectors (FPD) permit acquisition of distortion-free radiographs with a large field of view and high image quality. The present study was performed to evaluate pulmonary function using breathing chest radiography with a dynamic FPD. We report primary results of a clinical study and computer algorithm for quantifying and visualizing relative local pulmonary airflow. Dynamic chest radiographs of 18 subjects (1 emphysema, 2 asthma, 4 interstitial pneumonia, 1 pulmonary nodule, and 10 normal controls) were obtained during respiration using an FPD system. We measured respiratory changes in distance from the lung apex to the diaphragm (DLD) and pixel values in each lung area. Subsequently, the interframe differences (D-frame) and difference values between maximum inspiratory and expiratory phases (D-max) were calculated. D-max in each lung represents relative vital capacity (VC) and regional D-frames represent pulmonary airflow in each local area. D-frames were superimposed on dynamic chest radiographs in the form of color display (fusion images). The results obtained using our methods were compared with findings on computed tomography (CT) images and pulmonary functional test (PFT), which were examined before inclusion in the study. In normal subjects, the D-frames were distributed symmetrically in both lungs throughout all respiratory phases. However, subjects with pulmonary diseases showed D-frame distribution patterns that differed from the normal pattern. In subjects with air trapping, there were some areas with D-frames near zero indicated as colorless areas on fusion images. These areas also corresponded to the areas showing air trapping on computed tomography images. In asthma, obstructive abnormality was indicated by areas continuously showing D-frame near zero in the upper lung. Patients with interstitial pneumonia commonly showed fusion images with an uneven color distribution accompanied by increased D-frames in the area identified as normal on computed tomography images. Furthermore, measurement of DLD was very effective for evaluating diaphragmatic kinetics. This is a rapid and simple method for evaluation of respiratory kinetics for pulmonary diseases, which can reveal abnormalities in diaphragmatic kinetics and regional lung ventilation. Furthermore, quantification and visualization of respiratory kinetics is useful as an aid in interpreting dynamic chest radiographs.

Comparison of Online 6 Degree-of-Freedom Image Registration of Varian TrueBeam Cone-Beam CT and BrainLab ExacTrac X-Ray for Intracranial Radiosurgery.

PubMed

Li, Jun; Shi, Wenyin; Andrews, David; Werner-Wasik, Maria; Lu, Bo; Yu, Yan; Dicker, Adam; Liu, Haisong

2017-06-01

The study was aimed to compare online 6 degree-of-freedom image registrations of TrueBeam cone-beam computed tomography and BrainLab ExacTrac X-ray imaging systems for intracranial radiosurgery. Phantom and patient studies were performed on a Varian TrueBeam STx linear accelerator (version 2.5), which is integrated with a BrainLab ExacTrac imaging system (version 6.1.1). The phantom study was based on a Rando head phantom and was designed to evaluate isocenter location dependence of the image registrations. Ten isocenters at various locations representing clinical treatment sites were selected in the phantom. Cone-beam computed tomography and ExacTrac X-ray images were taken when the phantom was located at each isocenter. The patient study included 34 patients. Cone-beam computed tomography and ExacTrac X-ray images were taken at each patient's treatment position. The 6 degree-of-freedom image registrations were performed on cone-beam computed tomography and ExacTrac, and residual errors calculated from cone-beam computed tomography and ExacTrac were compared. In the phantom study, the average residual error differences (absolute values) between cone-beam computed tomography and ExacTrac image registrations were 0.17 ± 0.11 mm, 0.36 ± 0.20 mm, and 0.25 ± 0.11 mm in the vertical, longitudinal, and lateral directions, respectively. The average residual error differences in the rotation, roll, and pitch were 0.34° ± 0.08°, 0.13° ± 0.09°, and 0.12° ± 0.10°, respectively. In the patient study, the average residual error differences in the vertical, longitudinal, and lateral directions were 0.20 ± 0.16 mm, 0.30 ± 0.18 mm, 0.21 ± 0.18 mm, respectively. The average residual error differences in the rotation, roll, and pitch were 0.40°± 0.16°, 0.17° ± 0.13°, and 0.20° ± 0.14°, respectively. Overall, the average residual error differences were <0.4 mm in the translational directions and <0.5° in the rotational directions. ExacTrac X-ray image registration is comparable to TrueBeam cone-beam computed tomography image registration in intracranial treatments.

Spine Trabecular Bone Score as an Indicator of Bone Microarchitecture at the Peripheral Skeleton in Kidney Transplant Recipients.

PubMed

Luckman, Matthew; Hans, Didier; Cortez, Natalia; Nishiyama, Kyle K; Agarawal, Sanchita; Zhang, Chengchen; Nikkel, Lucas; Iyer, Sapna; Fusaro, Maria; Guo, Edward X; McMahon, Donald J; Shane, Elizabeth; Nickolas, Thomas L

2017-04-03

Studies using high-resolution peripheral quantitative computed tomography showed progressive abnormalities in cortical and trabecular microarchitecture and biomechanical competence over the first year after kidney transplantation. However, high-resolution peripheral computed tomography is a research tool lacking wide availability. In contrast, the trabecular bone score is a novel and widely available tool that uses gray-scale variograms of the spine image from dual-energy x-ray absorptiometry to assess trabecular quality. There are no studies assessing whether trabecular bone score characterizes bone quality in kidney transplant recipients. Between 2009 and 2010, we conducted a study to assess changes in peripheral skeletal microarchitecture, measured by high-resolution peripheral computed tomography, during the first year after transplantation in 47 patients managed with early corticosteroid-withdrawal immunosuppression. All adult first-time transplant candidates were eligible. Patients underwent imaging with high-resolution peripheral computed tomography and dual-energy x-ray absorptiometry pretransplantation and 3, 6, and 12 months post-transplantation. We now test if, during the first year after transplantation, trabecular bone score assesses the evolution of bone microarchitecture and biomechanical competence as determined by high-resolution peripheral computed tomography. At baseline and follow-up, among the 72% and 78%, respectively, of patients having normal bone mineral density by dual-energy x-ray absorptiometry, 53% and 50%, respectively, were classified by trabecular bone score as having high fracture risk. At baseline, trabecular bone score correlated with spine, hip, and ultradistal radius bone mineral density by dual-energy x-ray absorptiometry and cortical area, density, thickness, and porosity; trabecular density, thickness, separation, and heterogeneity; and stiffness and failure load by high-resolution peripheral computed tomography. Longitudinally, each percentage increase in trabecular bone score was associated with increases in trabecular number (0.35%±1.4%); decreases in trabecular thickness (-0.45%±0.15%), separation (-0.40%±0.15%), and network heterogeneity (-0.48%±0.20%); and increases in failure load (0.22%±0.09%) by high-resolution peripheral computed tomography (all P <0.05). Trabecular bone score may be a useful method to assess and monitor bone quality and strength and classify fracture risk in kidney transplant recipients. Copyright © 2017 by the American Society of Nephrology.

Spine Trabecular Bone Score as an Indicator of Bone Microarchitecture at the Peripheral Skeleton in Kidney Transplant Recipients

PubMed Central

Luckman, Matthew; Hans, Didier; Cortez, Natalia; Nishiyama, Kyle K.; Agarawal, Sanchita; Zhang, Chengchen; Nikkel, Lucas; Iyer, Sapna; Fusaro, Maria; Guo, Edward X.; McMahon, Donald J.; Shane, Elizabeth

2017-01-01

Background and objectives Studies using high-resolution peripheral quantitative computed tomography showed progressive abnormalities in cortical and trabecular microarchitecture and biomechanical competence over the first year after kidney transplantation. However, high-resolution peripheral computed tomography is a research tool lacking wide availability. In contrast, the trabecular bone score is a novel and widely available tool that uses gray-scale variograms of the spine image from dual-energy x-ray absorptiometry to assess trabecular quality. There are no studies assessing whether trabecular bone score characterizes bone quality in kidney transplant recipients. Design, settings, participants, & measurements Between 2009 and 2010, we conducted a study to assess changes in peripheral skeletal microarchitecture, measured by high-resolution peripheral computed tomography, during the first year after transplantation in 47 patients managed with early corticosteroid–withdrawal immunosuppression. All adult first-time transplant candidates were eligible. Patients underwent imaging with high-resolution peripheral computed tomography and dual-energy x-ray absorptiometry pretransplantation and 3, 6, and 12 months post-transplantation. We now test if, during the first year after transplantation, trabecular bone score assesses the evolution of bone microarchitecture and biomechanical competence as determined by high-resolution peripheral computed tomography. Results At baseline and follow-up, among the 72% and 78%, respectively, of patients having normal bone mineral density by dual-energy x-ray absorptiometry, 53% and 50%, respectively, were classified by trabecular bone score as having high fracture risk. At baseline, trabecular bone score correlated with spine, hip, and ultradistal radius bone mineral density by dual-energy x-ray absorptiometry and cortical area, density, thickness, and porosity; trabecular density, thickness, separation, and heterogeneity; and stiffness and failure load by high-resolution peripheral computed tomography. Longitudinally, each percentage increase in trabecular bone score was associated with increases in trabecular number (0.35%±1.4%); decreases in trabecular thickness (−0.45%±0.15%), separation (−0.40%±0.15%), and network heterogeneity (−0.48%±0.20%); and increases in failure load (0.22%±0.09%) by high-resolution peripheral computed tomography (all P<0.05). Conclusions Trabecular bone score may be a useful method to assess and monitor bone quality and strength and classify fracture risk in kidney transplant recipients. PMID:28348031

3D Printout Models vs. 3D-Rendered Images: Which Is Better for Preoperative Planning?

PubMed

Zheng, Yi-xiong; Yu, Di-fei; Zhao, Jian-gang; Wu, Yu-lian; Zheng, Bin

2016-01-01

Correct interpretation of a patient's anatomy and changes that occurs secondary to a disease process are crucial in the preoperative process to ensure optimal surgical treatment. In this study, we presented 3 different pancreatic cancer cases to surgical residents in the form of 3D-rendered images and 3D-printed models to investigate which modality resulted in the most appropriate preoperative plan. We selected 3 cases that would require significantly different preoperative plans based on key features identifiable in the preoperative computed tomography imaging. 3D volume rendering and 3D printing were performed respectively to create 2 different training ways. A total of 30, year 1 surgical residents were randomly divided into 2 groups. Besides traditional 2D computed tomography images, residents in group A (n = 15) reviewed 3D computer models, whereas in group B, residents (n = 15) reviewed 3D-printed models. Both groups subsequently completed an examination, designed in-house, to assess the appropriateness of their preoperative plan and provide a numerical score of the quality of the surgical plan. Residents in group B showed significantly higher quality of the surgical plan scores compared with residents in group A (76.4 ± 10.5 vs. 66.5 ± 11.2, p = 0.018). This difference was due in large part to a significant difference in knowledge of key surgical steps (22.1 ± 2.9 vs. 17.4 ± 4.2, p = 0.004) between each group. All participants reported a high level of satisfaction with the exercise. Results from this study support our hypothesis that 3D-printed models improve the quality of surgical trainee's preoperative plans. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

A novel forward projection-based metal artifact reduction method for flat-detector computed tomography.

PubMed

Prell, Daniel; Kyriakou, Yiannis; Beister, Marcel; Kalender, Willi A

2009-11-07

Metallic implants generate streak-like artifacts in flat-detector computed tomography (FD-CT) reconstructed volumetric images. This study presents a novel method for reducing these disturbing artifacts by inserting discarded information into the original rawdata using a three-step correction procedure and working directly with each detector element. Computation times are minimized by completely implementing the correction process on graphics processing units (GPUs). First, the original volume is corrected using a three-dimensional interpolation scheme in the rawdata domain, followed by a second reconstruction. This metal artifact-reduced volume is then segmented into three materials, i.e. air, soft-tissue and bone, using a threshold-based algorithm. Subsequently, a forward projection of the obtained tissue-class model substitutes the missing or corrupted attenuation values directly for each flat detector element that contains attenuation values corresponding to metal parts, followed by a final reconstruction. Experiments using tissue-equivalent phantoms showed a significant reduction of metal artifacts (deviations of CT values after correction compared to measurements without metallic inserts reduced typically to below 20 HU, differences in image noise to below 5 HU) caused by the implants and no significant resolution losses even in areas close to the inserts. To cover a variety of different cases, cadaver measurements and clinical images in the knee, head and spine region were used to investigate the effectiveness and applicability of our method. A comparison to a three-dimensional interpolation correction showed that the new approach outperformed interpolation schemes. Correction times are minimized, and initial and corrected images are made available at almost the same time (12.7 s for the initial reconstruction, 46.2 s for the final corrected image compared to 114.1 s and 355.1 s on central processing units (CPUs)).

Chest computed tomography scores are predictive of survival in patients with cystic fibrosis awaiting lung transplantation.

PubMed

Loeve, Martine; Hop, Wim C J; de Bruijne, Marleen; van Hal, Peter T W; Robinson, Phil; Aitken, Moira L; Dodd, Jonathan D; Tiddens, Harm A W M

2012-05-15

Up to one-third of patients with cystic fibrosis (CF) awaiting lung transplantation (LTX) die while waiting. Inclusion of computed tomography (CT) scores may improve survival prediction models such as the lung allocation score (LAS). This study investigated the association between CT and survival in patients with CF screened for LTX. Clinical data and chest CTs of 411 patients with CF screened for LTX between 1990 and 2005 were collected from 17 centers. CTs were scored with the Severe Advanced Lung Disease (SALD) four-category scoring system, including the components infection/inflammation (INF), air trapping/hypoperfusion (AT), normal/hyperperfusion (NOR), and bulla/cysts (BUL). The volume of each component was computed using semiautomated software. Survival analysis included Kaplan-Meier curves and Cox regression models. Three hundred and sixty-six (186 males) of 411 patients entered the waiting list (median age, 23 yr; range, 5-58 yr). Subsequently, 67 of 366 (18%) died while waiting, 263 of 366 (72%) underwent LTX, and 36 of 366 (10%) were awaiting LTX at the census date. INF and LAS were significantly associated with waiting list mortality in univariate analyses. The multivariate Cox model including INF and LAS grouped in tertiles, and comparing tertiles 2 and 3 with tertile 1, showed waiting list mortality hazard ratios of 1.62 (95% confidence interval [95% CI], 0.78-3.36; P = 0.19) and 2.65 (95% CI, 1.35-5.20; P = 0.005) for INF, and 1.42 (95% CI, 0.63-3.24; P = 0.40), and 2.32 (95% CI, 1.17-4.60; P = 0.016) for LAS, respectively. These results indicated that INF and LAS had significant, independent predictive value for survival. CT score INF correlates with survival, and adds to the predictive value of LAS.

X-ray Micro-Tomography of Ablative Heat Shield Materials

NASA Technical Reports Server (NTRS)

Panerai, Francesco; Ferguson, Joseph; Borner, Arnaud; Mansour, Nagi N.; Barnard, Harold S.; MacDowell, Alastair A.; Parkinson, Dilworth Y.

2016-01-01

X-ray micro-tomography is a non-destructive characterization technique that allows imaging of materials structures with voxel sizes in the micrometer range. This level of resolution makes the technique very attractive for imaging porous ablators used in hypersonic entry systems. Besides providing a high fidelity description of the material architecture, micro-tomography enables computations of bulk material properties and simulations of micro-scale phenomena. This presentation provides an overview of a collaborative effort between NASA Ames Research Center and Lawrence Berkeley National Laboratory, aimed at developing micro-tomography experiments and simulations for porous ablative materials. Measurements are carried using x-rays from the Advanced Light Source at Berkeley Lab on different classes of ablative materials used in NASA entry systems. Challenges, strengths and limitations of the technique for imaging materials such as lightweight carbon-phenolic systems and woven textiles are discussed. Computational tools developed to perform numerical simulations based on micro-tomography are described. These enable computations of material properties such as permeability, thermal and radiative conductivity, tortuosity and other parameters that are used in ablator response models. Finally, we present the design of environmental cells that enable imaging materials under simulated operational conditions, such as high temperature, mechanical loads and oxidizing atmospheres.Keywords: Micro-tomography, Porous media, Ablation

Image reconstruction from few-view CT data by gradient-domain dictionary learning.

PubMed

Hu, Zhanli; Liu, Qiegen; Zhang, Na; Zhang, Yunwan; Peng, Xi; Wu, Peter Z; Zheng, Hairong; Liang, Dong

2016-05-21

Decreasing the number of projections is an effective way to reduce the radiation dose exposed to patients in medical computed tomography (CT) imaging. However, incomplete projection data for CT reconstruction will result in artifacts and distortions. In this paper, a novel dictionary learning algorithm operating in the gradient-domain (Grad-DL) is proposed for few-view CT reconstruction. Specifically, the dictionaries are trained from the horizontal and vertical gradient images, respectively and the desired image is reconstructed subsequently from the sparse representations of both gradients by solving the least-square method. Since the gradient images are sparser than the image itself, the proposed approach could lead to sparser representations than conventional DL methods in the image-domain, and thus a better reconstruction quality is achieved. To evaluate the proposed Grad-DL algorithm, both qualitative and quantitative studies were employed through computer simulations as well as real data experiments on fan-beam and cone-beam geometry. The results show that the proposed algorithm can yield better images than the existing algorithms.

Tunable, biodegradable gold nanoparticles as contrast agents for computed tomography and photoacoustic imaging

PubMed Central

Cheheltani, Rabee; Ezzibdeh, Rami M.; Chhour, Peter; Pulaparthi, Kumidini; Kim, Johoon; Jurcova, Martina; Hsu, Jessica C.; Blundell, Cassidy; Litt, Harold I.; Ferrari, Victor A.; Allcock, Harry R.; Sehgal, Chandra M.; Cormode, David P.

2016-01-01

Gold nanoparticles (AuNP) have been proposed for many applications in medicine. Although large AuNP (>5.5 nm) are desirable for their longer blood circulation and accumulation in diseased tissues, small AuNP (<5.5 nm) are required for excretion via the kidneys. We present a novel platform where small, excretable AuNP are encapsulated into biodegradable poly di(carboxylatophenoxy)phosphazene (PCPP) nanospheres. These larger nanoparticles (Au-PCPP) can perform their function as contrast agents, then subsequently break down into harmless byproducts and release the AuNP for swift excretion. Homogeneous Au-PCPP were synthesized using a microfluidic device. The size of the Au-PCPP can be controlled by the amount of polyethylene glycol-polylysine (PEG-PLL) block co-polymer in the formulation. Synthesis of Au-PCPP nanoparticles and encapsulation of AuNP in PCPP were evaluated using transmission electron microscopy and their biocompatibility and biodegradability confirmed in vitro. The Au-PCPP nanoparticles were found to produce strong computed tomography contrast. The UV-Vis absorption peak of Au-PCPP can be tuned into the near infrared region via inclusion of varying amounts of AuNP and controlling the nanoparticle size. In vitro and in vivo experiments demonstrated the potential of Au-PCPP as contrast agents for photoacoustic imaging. Therefore, Au-PCPP nanoparticles have high potency as contrast agents for two imaging modalities, as well as being biocompatible and biodegradable, and thus represent a platform with potential for translation into the clinic. PMID:27322961

Effect of Metal Artifacts on Detection of Vertical Root Fractures Using Two Cone Beam Computed Tomography Systems.

PubMed

Safi, Yaser; Aghdasi, Mohammad Mehdi; Ezoddini-Ardakani, Fatemeh; Beiraghi, Samira; Vasegh, Zahra

2015-01-01

Vertical root fracture (VRF) is common in endodontically treated teeth. Conventional and digital radiographies have limitations for detection of VRFs. Cone-beam computed tomography (CBCT) offers greater detection accuracy of VRFs in comparison with conventional radiography. This study compared the effects of metal artifacts on detection of VRFs by using two CBCT systems. Eighty extracted premolars were selected and sectioned at the level of the cemento enamel junction (CEJ). After preparation, root canals were filled with gutta-percha. Subsequently, two thirds of the root fillings were removed for post space preparation and a custom-made post was cemented into each canal. The teeth were randomly divided into two groups (n=40). In the test group, root fracture was created with Instron universal testing machine. The control teeth remained intact. CBCT scans of all teeth were obtained with either New Tom VGI or Soredex Scanora 3D. Three observers analyzed the images for detection of VRF. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for VRF detection and percentage of probable cases were calculated for each imaging system and compared using non-parametric tests considering the non-normal distribution of data. The inter-observer reproducibility was calculated using the weighted kappa coefficient. There were no statistically significant differences in sensitivity, specificity, PPV and NPV between the two CBCT systems. The effect of metal artifacts on VRF detection was not significantly different between the two CBCT systems.

Nasopharyngeal Carcinoma with Cystic Cervical Metastasis Masquerading as Branchial Cleft Cyst: A Potential Pitfall in Diagnosis and Management.

PubMed

Sai-Guan, Lum; Min-Han, Kong; Kah-Wai, Ngan; Mohamad-Yunus, Mohd-Razif

2017-03-01

Most metastatic lymph nodes from head and neck malignancy are solid. Cystic nodes are found in 33% - 61% of carcinomas arise from Waldeyer's ring, of which only 1.8% - 8% originate are from the nasopharynx. Some cystic cervical metastases were initially presumed to be branchial cleft cyst. This case report aims to highlight the unusual presentation of cystic cervical metastasis secondary to nasopharyngeal carcinoma in a young adult. The histopathology, radiological features and management strategy were discussed. A 36-year-old man presented with a solitary cystic cervical swelling, initially diagnosed as branchial cleft cyst. Fine needle aspiration yielded 18 ml of straw-coloured fluid. During cytological examination no atypical cells were observed. Computed tomography of the neck showed a heterogeneous mass with multiseptation medial to the sternocleidomastoid muscle. Histopathological examination of the mass, post excision, revealed a metastatic lymph node. A suspicious mucosal lesion at the nasopharynx was detected after repeated thorough head and neck examinations and the biopsy result confirmed undifferentiated nasopharyngeal carcinoma. Cystic cervical metastasis may occur in young patients under 40 years. The primary tumour may not be obvious during initial presentation because it mimicks benign branchial cleft cyst clinically. Retrospective review of the computed tomography images revealed features that were not characteristic of simple branchial cleft cyst. The inadequacy of assessment and interpretation had lead to the error in diagnosis and subsequent management. Metastatic head and neck lesion must be considered in a young adult with a cystic neck mass.

Antifungal prophylaxis with fluconazole in allogeneic stem cell transplantation recipients who had prior invasive aspergillosis with subsequent complete resolution by computed tomography.

PubMed

Akahoshi, Yu; Kimura, Shun-Ichi; Gomyo, Ayumi; Hayakawa, Jin; Tamaki, Masaharu; Harada, Naonori; Kusuda, Machiko; Kameda, Kazuaki; Ugai, Tomotaka; Wada, Hidenori; Ishihara, Yuko; Kawamura, Koji; Sakamoto, Kana; Sato, Miki; Terasako-Saito, Kiriko; Kikuchi, Misato; Nakasone, Hideki; Kako, Shinichi; Kanda, Yoshinobu

2018-04-01

Consensus has yet to be reached regarding secondary prophylaxis in allogeneic hematopoietic stem cell transplantation (HSCT) with a complete resolution of invasive aspergillosis (IA) confirmed by chest computed tomography (CT). We retrospectively evaluated the feasibility of antifungal prophylaxis with fluconazole in allogeneic HSCT recipients who had previously developed IA which showed complete resolution as confirmed by chest CT before HSCT. Consecutive adult patients who underwent allogeneic HSCT at our institution and who had received fluconazole as systemic antifungal prophylaxis from June 2007 to January 2015 were included. We compared the clinical outcomes between patients with a past history of IA who showed a complete resolution of chest CT abnormalities (n = 13) and those without a previous history of IA (n = 137). The cumulative incidence of proven or probable IA was 8.8% in the group without a past history of IA and 0.0% in the group with a past history of IA (p = .268). The cumulative incidence of proven or probable invasive fungal disease (IFD) within 100 days after allogeneic HSCT was 10.9% in the group without a past history of IA and 15.4% in the group with a past history of IA (p = .647). Fluconazole was switched to anti-mould agents in two-thirds of the patients in each group by day 100 after HSCT. Fluconazole was confirmed to be an acceptable prophylactic agent early after allogeneic HSCT in appropriately selected patients.

Resolution, sensitivity, and in vivo application of high-resolution computed tomography for titanium-coated polymethyl methacrylate (PMMA) dental implants.

PubMed

Cuijpers, Vincent M J I; Jaroszewicz, Jacub; Anil, Sukumaran; Al Farraj Aldosari, Abdullah; Walboomers, X Frank; Jansen, John A

2014-03-01

The aims of this study were (i) to determine the spatial resolution and sensitivity of micro- versus nano-computed tomography (CT) techniques and (ii) to validate micro- versus nano-CT in a dog dental implant model, comparative to histological analysis. To determine spatial resolution and sensitivity, standardized reference samples containing standardized nano- and microspheres were prepared in polymer and ceramic matrices. Thereafter, 10 titanium-coated polymer dental implants (3.2 mm in Ø by 4 mm in length) were placed in the mandible of Beagle dogs. Both micro- and nano-CT, as well as histological analyses, were performed. The reference samples confirmed the high resolution of the nano-CT system, which was capable of revealing sub-micron structures embedded in radiodense matrices. The dog implantation study and subsequent statistical analysis showed equal values for bone area and bone-implant contact measurements between micro-CT and histology. However, because of the limited sample size and field of view, nano-CT was not rendering reliable data representative of the entire bone-implant specimen. Micro-CT analysis is an efficient tool to quantitate bone healing parameters at the bone-implant interface, especially when using titanium-coated PMMA implants. Nano-CT is not suitable for such quantification, but reveals complementary morphological information rivaling histology, yet with the advantage of a 3D visualization. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Predicting hollow viscus injury in blunt abdominal trauma with computed tomography.

PubMed

Bhagvan, Savitha; Turai, Matthew; Holden, Andrew; Ng, Alexander; Civil, Ian

2013-01-01

Evaluation of blunt abdominal trauma is controversial. Computed tomography (CT) of the abdomen is commonly used but has limitations, especially in excluding hollow viscus injury in the presence of solid organ injury. To determine whether CT reports alone could be used to direct operative treatment in abdominal trauma, this study was undertaken. The trauma database at Auckland City Hospital was accessed for patients who had abdominal CT and subsequent laparotomy during a five-year period. The CT scans were reevaluated by a consultant radiologist who was blinded to operative findings. The CT findings were correlated with the operative findings. Between January 2002 and December 2007, 1,250 patients were evaluated for blunt abdominal injury with CT. A subset of 78 patients underwent laparotomy, and this formed the study group. The sensitivity and specificity of CT scan in predicting hollow viscus injury was 55.33 and 92.06 % respectively. The positive and negative predictive values were 61.53 and 89.23 % respectively. Presence of free fluid in CT scan was sensitive in diagnosing hollow viscus injury (90 %). Specific findings for hollow viscus injuries on CT scan were free intraperitoneal air (93 %), retroperitoneal air (100 %), oral contrast extravasation (100 %), bowel wall defect (98 %), patchy bowel enhancement (97 %), and mesenteric abnormality (94 %). CT alone cannot be used as a screening tool for hollow viscus injury. The decision to operate in hollow viscus injury has to be based on mechanism of injury and clinical findings together with radiological evidence.

Emergency ultrasound in the acute assessment of haemothorax

PubMed Central

Brooks, A; Davies, B; Smethhurst, M; Connolly, J

2004-01-01

Aims: To evaluate thoracic ultrasound for the detection of haemothorax in patients with thoracic trauma against established investigations. Methods: Thoracic ultrasound was performed as an extension of the standard focused assessment with sonography for trauma (FAST) protocol used at the Queen's Medical Centre for the assessment of adult patients with torso trauma. Fluid was sought in both pleural cavities using a hand portable ultrasound system by one of two non-radiologists trained in FAST. Findings were compared against subsequent investigations/procedures performed at the discretion of the attending emergency physician—supine chest radiography, intercostal drain, computed tomography, or thoracotomy. The sensitivity of the technique and the time taken to diagnosis for each investigation were recorded. Results: Sixty one patients, 54 (89%) after blunt trauma, underwent thoracic ultrasound evaluation during the study. Twelve patients had a haemothorax detected by ultrasound and confirmed by computed tomography or by tube thoracostomy. Four haemothoraces detected on ultrasound were not apparent on trauma chest radiography. There were 12 true positives, 48 true negatives, no false positives, and one false negative scan. The sensitivity of ultrasound was 92% and specificity 100% with a positive predictive value of 100% and negative predictive value 98% for the detection of haemothorax after trauma. Conclusions: Emergency ultrasound of the chest performed as part of the primary survey of the traumatised patient can rapidly and accurately diagnose haemothorax and is a valuable tool to augment the immediate clinical assessment of these patients. PMID:14734374

Cochlear Implant Electrode Localization Using an Ultra-High Resolution Scan Mode on Conventional 64-Slice and New Generation 192-Slice Multi-Detector Computed Tomography.

PubMed

Carlson, Matthew L; Leng, Shuai; Diehn, Felix E; Witte, Robert J; Krecke, Karl N; Grimes, Josh; Koeller, Kelly K; Bruesewitz, Michael R; McCollough, Cynthia H; Lane, John I

2017-08-01

A new generation 192-slice multi-detector computed tomography (MDCT) clinical scanner provides enhanced image quality and superior electrode localization over conventional MDCT. Currently, accurate and reliable cochlear implant electrode localization using conventional MDCT scanners remains elusive. Eight fresh-frozen cadaveric temporal bones were implanted with full-length cochlear implant electrodes. Specimens were subsequently scanned with conventional 64-slice and new generation 192-slice MDCT scanners utilizing ultra-high resolution modes. Additionally, all specimens were scanned with micro-CT to provide a reference criterion for electrode position. Images were reconstructed according to routine temporal bone clinical protocols. Three neuroradiologists, blinded to scanner type, reviewed images independently to assess resolution of individual electrodes, scalar localization, and severity of image artifact. Serving as the reference standard, micro-CT identified scalar crossover in one specimen; imaging of all remaining cochleae demonstrated complete scala tympani insertions. The 192-slice MDCT scanner exhibited improved resolution of individual electrodes (p < 0.01), superior scalar localization (p < 0.01), and reduced blooming artifact (p < 0.05), compared with conventional 64-slice MDCT. There was no significant difference between platforms when comparing streak or ring artifact. The new generation 192-slice MDCT scanner offers several notable advantages for cochlear implant imaging compared with conventional MDCT. This technology provides important feedback regarding electrode position and course, which may help in future optimization of surgical technique and electrode design.

CAD-RADS™: Coronary Artery Disease - Reporting and Data System: An Expert Consensus Document of the Society of Cardiovascular Computed Tomography (SCCT), the American College of Radiology (ACR) and the North American Society for Cardiovascular Imaging (NASCI). Endorsed by the American College of Cardiology.

PubMed

Cury, Ricardo C; Abbara, Suhny; Achenbach, Stephan; Agatston, Arthur; Berman, Daniel S; Budoff, Matthew J; Dill, Karin E; Jacobs, Jill E; Maroules, Christopher D; Rubin, Geoffrey D; Rybicki, Frank J; Schoepf, U Joseph; Shaw, Leslee J; Stillman, Arthur E; White, Charles S; Woodard, Pamela K; Leipsic, Jonathon A

2016-12-01

The intent of CAD-RADS - Coronary Artery Disease Reporting and Data System is to create a standardized method to communicate findings of coronary CT angiography (coronary CTA) in order to facilitate decision-making regarding further patient management. The suggested CAD-RADS classification is applied on a per-patient basis and represents the highest-grade coronary artery lesion documented by coronary CTA. It ranges from CAD-RADS 0 (Zero) for the complete absence of stenosis and plaque to CAD-RADS 5 for the presence of at least one totally occluded coronary artery and should always be interpreted in conjunction with the impression found in the report. Specific recommendations are provided for further management of patients with stable or acute chest pain based on the CAD-RADS classification. The main goal of CAD-RADS is to standardize reporting of coronary CTA results and to facilitate communication of test results to referring physicians along with suggestions for subsequent patient management. In addition, CAD-RADS will provide a framework of standardization that may benefit education, research, peer-review and quality assurance with the potential to ultimately result in improved quality of care. Copyright © 2016 Society of Cardiovascular Computed Tomography and the American College of Radiology. Published by Elsevier Inc. All rights reserved.

Prevertebral space effusion caused by the breaking of swollen lymphonodi retropharynici in nasopharyngeal carcinoma: A case report.

PubMed

Liu, Lian-Hua; Yang, Xiao-Feng

2016-06-01

A 20-year-old male presented to hospital with blood in the mucus, which had occurred for 6 months, and was diagnosed with nasopharyngeal carcinoma (NPC). Due to passive smoking, the patient developed a constant and violent cough, pain behind the right ear and swelling of the retropharynx. The results of a computed tomography scan, which was performed during re-examination of the patient, revealed that the right lymphonodi retropharynici had decreased in size and the hypodense shadow of the prevertebral space had become clear. Therefore, the retropharyngeal pressure was suspected to be increased due to the violent cough. Consequently, the increased pressure may have caused the swollen lymph nodes on the right side of the pharynx to break, which allowed the necrotic liquid to seep into the prevertebral space and result in effusion. Subsequent to 5 days of treatment with methylprednisolone (40 mg ivgtt qd, d1-5), the results from the cone bean computed tomography examination, which had been performed prior to radiotherapy, indicated that the retropharyngeal swelling had improved and the prevertebral space had returned to normal. To the best of our knowledge, the present study is the first reported case of effusion in the prevertebral space caused by the breaking of swollen lymphonodi retropharynici in NPC. The present study acts as a reminder of the possible delays in the treatments for head and neck tumor patients that demonstrate swollen retropharyngeal lymph nodes due to the occurrence of effusion in the prevertebral space.

The value of liver magnetic resonance imaging in patients with findings of resectable pancreatic cancer on computed tomography.

PubMed

Chew, Cindy; O'Dwyer, Patrick J

2016-06-01

Accurate staging of patients with pancreatic cancer is important to avoid unnecessary operations. The aim of this study was to prospectively assess the impact of magnetic resonance (MR) imaging on preoperative staging of liver in patients with findings of resectable pancreatic cancer on computed tomography (CT). All patients who presented to a tertiary referral centre with pancreatic cancer between April 2012 and December 2013 were included in the study. Patients with findings of resectable disease on CT underwent further liver diffusion-weighted MR imaging, using a hepatocyte-specific contrast agent. A total of 583 patients with pancreatic cancer were referred. 69 (11.8%) had resectable disease on CT. Of these 69 patients, 16 (23.2%) had liver metastases on MR imaging, while 6 (8.7%) had indeterminate lesions. Of the 16 patients with positive MR imaging findings of liver metastases, 11 died of pancreatic cancer, with a mean survival time of nine months (95% confidence interval [CI] 5.22-14.05). The mean survival time of the 47 patients with negative MR imaging findings was 16 months (95% CI 14.33-18.10; p = 0.001). Subsequently, 22 of these patients underwent surgery, and only 1 (4.5%) patient was found to have liver metastasis at surgery. The results of the present study indicate that MR imaging improves the staging of disease in patients with resectable pancreatic cancer. Copyright: © Singapore Medical Association.

Predicting round window niche visibility via the facial recess using high-resolution computed tomography.

PubMed

Kashio, Akinori; Sakamoto, Takashi; Karino, Shotaro; Kakigi, Akinobu; Iwasaki, Shinichi; Yamasoba, Tatsuya

2015-01-01

To predict round window niche (RWN) visibility using high-resolution computed tomography (HRCT). Case series with chart review. Academic tertiary care center. We retrospectively reviewed 70 cochlear implant ears that underwent presurgical axial HRCT with a surgical video recorder. The visibility of the RWN was classified into three types: 17 as invisible or nearly invisible, 22 as partially visible, and 31 as fully visible. Next, we measured the following three radiologic parameters: 1) the angle of the external auditory canal (EAC) relative to the cochlear basal turn, 2) the width of the facial recess, and 3) the relative location of the facial nerve (FN) to the cochlear basal turn. These were compared with the RWN visibility. Subsequently, to predict the RWN visibility, a line was created parallel to the EAC line and along the anterior lateral FN. The location of the line relative to the round window membrane was compared with the RWN view. In cases that had poor RWN visibility, the angle of the posterior canal wall portion of the EAC relative to the cochlear basal turn was significantly smaller and the location of the FN to the cochlear basal turn was closer. The location of the prediction line to the round window membrane highly predicted the RWN view during the surgery. The RWN visibility and the preoperative HRCT findings showed a high correlation. Drawing the prediction line is a simple and useful way for preoperatively predicting the RWN visibility in cochlear implant surgery.

Low-dose cerebral perfusion computed tomography image restoration via low-rank and total variation regularizations

PubMed Central

Niu, Shanzhou; Zhang, Shanli; Huang, Jing; Bian, Zhaoying; Chen, Wufan; Yu, Gaohang; Liang, Zhengrong; Ma, Jianhua

2016-01-01

Cerebral perfusion x-ray computed tomography (PCT) is an important functional imaging modality for evaluating cerebrovascular diseases and has been widely used in clinics over the past decades. However, due to the protocol of PCT imaging with repeated dynamic sequential scans, the associative radiation dose unavoidably increases as compared with that used in conventional CT examinations. Minimizing the radiation exposure in PCT examination is a major task in the CT field. In this paper, considering the rich similarity redundancy information among enhanced sequential PCT images, we propose a low-dose PCT image restoration model by incorporating the low-rank and sparse matrix characteristic of sequential PCT images. Specifically, the sequential PCT images were first stacked into a matrix (i.e., low-rank matrix), and then a non-convex spectral norm/regularization and a spatio-temporal total variation norm/regularization were then built on the low-rank matrix to describe the low rank and sparsity of the sequential PCT images, respectively. Subsequently, an improved split Bregman method was adopted to minimize the associative objective function with a reasonable convergence rate. Both qualitative and quantitative studies were conducted using a digital phantom and clinical cerebral PCT datasets to evaluate the present method. Experimental results show that the presented method can achieve images with several noticeable advantages over the existing methods in terms of noise reduction and universal quality index. More importantly, the present method can produce more accurate kinetic enhanced details and diagnostic hemodynamic parameter maps. PMID:27440948

Abernethy malformation with portal vein aneurysm in a child

PubMed Central

Chandrashekhara, Sheragaru H.; Bhalla, Ashu Seith; Gupta, Arun Kumar; Vikash, C. S.; Kabra, Susheel Kumar

2011-01-01

Abernethy malformation is an extremely rare anomaly of the splanchnic venous system. We describe multidetector computed tomography findings of an incidentally detected Abernethy malformation with portal vein aneurysm in a two-and-half-year old child. The computed tomography scan was performed for the evaluation of respiratory distress, poor growth, and loss of appetite. PMID:21430844

Transmission of Hepatitis C Virus during Computed Tomography Scanning with Contrast

PubMed Central

Rius, Cristina; Caylà, Joan A.

2008-01-01

Six cases of acute hepatitis C related to computed tomography scanning with contrast were identified in 3 hospitals. A patient with chronic hepatitis C had been subjected to the same procedure immediately before each patient who developed acute infection. Viral molecular analysis showed identity between isolates from cases with acute and chronic hepatitis C. PMID:18258135

An Integrated Teaching Method of Gross Anatomy and Computed Tomography Radiology

ERIC Educational Resources Information Center

Murakami, Tohru; Tajika, Yuki; Ueno, Hitoshi; Awata, Sachiko; Hirasawa, Satoshi; Sugimoto, Maki; Kominato, Yoshihiko; Tsushima, Yoshito; Endo, Keigo; Yorifuji, Hiroshi

2014-01-01

It is essential for medical students to learn and comprehend human anatomy in three dimensions (3D). With this in mind, a new system was designed in order to integrate anatomical dissections with diagnostic computed tomography (CT) radiology. Cadavers were scanned by CT scanners, and students then consulted the postmortem CT images during cadaver…

Computed tomography findings of gaseous necrosis in epithelial ovarian cancer: a report of three cases.

PubMed

Cronin, Paul; Crosse, Barbara; Lane, Geoff; Spencer, John A

2002-01-01

Necrosis in pathologic specimens of ovarian cancer is well documented; however, computed tomography (CT) evidence of gaseous necrosis in the absence of fistulation with bowel has not yet been described. We report three cases of ovarian adenocarcinoma that on CT showed evidence of gross gaseous necrosis, mimicking a pelvic abscess.

Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance

Science.gov Websites

Finding Aids dropdown arrow Site Map A-Z Index Menu Synopsis Non-medical Uses of Computed Tomography (CT materials characterizations, and to provide non-destructive evaluations for discovering flaws in parts presence and facilitate the recovery/extraction of oil, water, coal, and/or gas; and to provide non

Utilization of high resolution computed tomography to visualize the three dimensional structure and function of plant vasculature

USDA-ARS?s Scientific Manuscript database

High resolution x-ray computed tomography (HRCT) is a non-destructive diagnostic imaging technique with sub-micron resolution capability that is now being used to evaluate the structure and function of plant xylem network in three dimensions (3D). HRCT imaging is based on the same principles as medi...

Tangential scanning of hardwood logs: developing an industrial computer tomography scanner

Treesearch

Nand K. Gupta; Daniel L. Schmoldt; Bruce Isaacson

1999-01-01

It is generally believed that noninvasive scanning of hardwood logs such as computer tomography (CT) scanning prior to initial breakdown will greatly improve the processing of logs into lumber. This belief, however, has not translated into rapid development and widespread installation of industrial CT scanners for log processing. The roadblock has been more operational...

An Easily Assembled Laboratory Exercise in Computed Tomography

ERIC Educational Resources Information Center

Mylott, Elliot; Klepetka, Ryan; Dunlap, Justin C.; Widenhorn, Ralf

2011-01-01

In this paper, we present a laboratory activity in computed tomography (CT) primarily composed of a photogate and a rotary motion sensor that can be assembled quickly and partially automates data collection and analysis. We use an enclosure made with a light filter that is largely opaque in the visible spectrum but mostly transparent to the near…

Documentation of the ISA Micro Computed Tomography System

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

Brown, William D.; Smith, Jerel A.

2013-12-18

This document is intended to provide information on the ISA Micro Computed Tomography (MicroCT) system that will be installed in Yavne, Israel. X-ray source, detector, and motion control hardware are specified as well as specimen platforms, containers, and reference material types. Most of the details on the system are derived from Reference 1 and 2.

The Role of High-resolution Peripheral Quantitative Computed Tomography as a Biomarker for Joint Damage in Inflammatory Arthritis.

PubMed

Tam, Lai-Shan

2016-10-01

Since 2011, members of the SPECTRA Collaboration (Study grouP for xtrEme-Computed Tomography in Rheumatoid Arthritis) have investigated the validity, reliability, and responsiveness of high-resolution peripheral quantitative computed tomography (HR-pQCT) as a biomarker for joint damage in inflammatory arthritis. Presented in this series of articles are a systematic review of HR-pQCT-related findings to date, a review of selected images of cortical and subchondral trabecular bone of metacarpophalangeal (MCP) joints, results of a consensus process to standardize the definition of erosions and their quantification, as well as an examination of the effect of joint flexion on width and volume assessment of the joint space.

Electron tomography and computer visualisation of a three-dimensional 'photonic' crystal in a butterfly wing-scale.

PubMed

Argyros, A; Manos, S; Large, M C J; McKenzie, D R; Cox, G C; Dwarte, D M

2002-01-01

A combination of transmission electron tomography and computer modelling has been used to determine the three-dimensional structure of the photonic crystals found in the wing-scales of the Kaiser-I-Hind butterfly (Teinopalpus imperialis). These scales presented challenges for electron microscopy because the periodicity of the structure was comparable to the thickness of a section and because of the complex connectivity of the object. The structure obtained has been confirmed by taking slices of the three-dimensional computer model constructed from the tomography and comparing these with transmission electron microscope (TEM) images of microtomed sections of the actual scale. The crystal was found to have chiral tetrahedral repeating units packed in a triclinic lattice.

Dysphagia lusorium in elderly: A case report

PubMed Central

Kantarceken, Bulent; Bulbuloglu, Ertan; Yuksel, Murvet; Cetinkaya, Ali

2004-01-01

AIM: Late unset of dysphagia due to vascular abnormalities is a rare condition. We aimed to present a case of right subclavian artery abnormalities caused dysphagia in the elderly. METHODS: A 68-year-old female was admitted with dysphagia seven months ago. Upper endoscopic procedures and routine examinations could not demonstrate any etiology. Multislice computed thorax tomography was performed for probable extra- esophagial lesions. RESULTS: Multislice computed thorax tomography showed right subclavian artery abnormality and esophagial compression with this aberrant artery. CONCLUSION: Causes of dysphagia in the elderly are commonly malignancies, strictures and/or motility disorders. If routine examinations and endoscopic procedures fail to show any etiology, rare vascular abnormalities can be considered in such patients. Multislice computed tomography is a usefull choice in such conditions. PMID:15285045

Finance for practicing radiologists.

PubMed

Berlin, Jonathan W; Lexa, Frank James

2005-03-01

This article reviews basic finance for radiologists. Using the example of a hypothetical outpatient computed tomography center, readers are introduced to the concept of net present value. This concept refers to the current real value of anticipated income in the future, realizing that revenue in the future has less value than it does today. Positive net present value projects add wealth to a practice and should be pursued. The article details how costs and revenues for a hypothetical outpatient computed tomography center are determined and elucidates the difference between fixed costs and variable costs. The article provides readers with the steps used to calculate the break-even volume for an outpatient computed tomography center given situation-specific assumptions regarding staff, equipment lease rates, rent, and third-party payer mix.

Contrast‐enhanced computed tomography with myocardial three‐dimensional printing can guide treatment in symptomatic hypertrophic obstructive cardiomyopathy

PubMed Central

Hamatani, Yasuhiro; Amaki, Makoto; Kanzaki, Hideaki; Yamashita, Kizuku; Nakashima, Yasuteru; Shibata, Atsushi; Okada, Atsushi; Takahama, Hiroyuki; Hasegawa, Takuya; Shimahara, Yusuke; Sugano, Yasuo; Fujita, Tomoyuki; Shiraishi, Isao; Yasuda, Satoshi; Kobayashi, Junjiro

2017-01-01

Abstract Both surgical myectomy and percutaneous transluminal septal myocardial ablation are effective treatments for drug‐refractory symptomatic hypertrophic obstructive cardiomyopathy (HOCM). However, in some cases, it is not easy to elucidate the abnormal structure of left ventricular outflow obstruction to adopt these treatments. Here, we presented a young female patient with drug‐refractory symptomatic HOCM. In this case, contrast‐enhanced computed tomography enabled us to assess the suitability of percutaneous transluminal septal myocardial ablation. By creating three‐dimensional printed models using computed tomography data, we could also visualize intracardiac structure and simulate the surgical procedure. A multimodality assessment strategy is useful for evaluating patients complicated with drug‐refractory symptomatic HOCM. PMID:29154429

Evaluation of acoustic tomography for tree decay detection

Treesearch

Shanquing Liang; Xiping Wang; Janice Wiedenbeck; Zhiyong Cai; Feng Fu

2008-01-01

In this study, the acoustic tomography technique was used to detect internal decay in high value black cherry (Prunus seratina) trees. Two-dimensional images of the cross sections of the tree samples were constructed using PiCUS Q70 software. The trees were felled following the field test, and a disc from each testing elevation was subsequently cut...

Patients who reattend after head injury: a high risk group.

PubMed Central

Voss, M.; Knottenbelt, J. D.; Peden, M. M.

1995-01-01

OBJECTIVE--To assess risk factors for important neurosurgical effects in patients who reattend after head injury. DESIGN--Retrospective study. SUBJECTS--606 patients who reattended a trauma unit after minor head injury. MAIN OUTCOME MEASURES--Intracranial abnormality detected on computed tomography or the need for neurosurgical intervention. RESULTS--Five patients died: two from unrelated causes and three from raised intracranial pressure. On multiple regression analysis the only significant predictor for both abnormality on computed tomography (14.4% of reattenders) and the need for operation (5% of reattenders) was vault fracture seen on the skull radiograph (P < 10(-6)); predictors for abnormal computed tomogram were a Glasgow coma scale score < 15 at either first or second attendance (P < 0.0001) and convulsion at second attendance (P < 0.05); predictive for operation only was penetrating injury of the skull (P < 10(-6)). On contingency table analysis these associations were confirmed. In addition significant associations with both abnormality on computed tomography and operation were focal neurological abnormality, weakness, or speech disturbance. Amnesia or loss of consciousness at the time of initial injury, personality change, and seizures were significantly associated only with abnormality on computed tomography. Headache, dizziness, nausea, and vomiting were common in reattenders but were found to have no independent significance. CONCLUSIONS--All patients who reattend after head injury should undergo computed tomography as at least 14% of scans can be expected to yield positive results. Where this facility is not available patients with predictors for operation should be urgently referred for neurosurgical opinion. Other patients can be readmitted and need referral only if symptoms persist despite symptomatic treatment or there is neurological deterioration while under observation. These patients are a high risk group and should be treated seriously. PMID:8520273

Lung Hot Spot Without Corresponding Computed Tomography Abnormality on Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography: Artifactual or Real, Iatrogenic or Pathologic?

PubMed

Liu, Yiyan

Focal lung uptake without corresponding lesions or abnormalities on computed tomography (CT) scan poses a dilemma in the interpretation of fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). A limited number of case reports have previously suggested an artifactual or iatrogenic nature of the uptake. In the present study, 8 relevant cases were included within a retrospective search of the database. Medical records were reviewed for follow-up radiological and pathologic information. In 7 of 8 cases with focal increased FDG uptake but no corresponding lesions or abnormalities on CT scan, the lung hot spots were artifactual or iatrogenic upon follow-up diagnostic chest CT or repeated PET/CT or both the scans. Microemboli were most likely a potential cause of the pulmonary uptake, with or without partial paravenous injection. One case in the series had a real pulmonary lesion demonstrated on follow-up PET/CT scans and on surgical pathology, although the initial integrated CT and follow-up diagnostic chest CT scans revealed negative findings to demonstrate pulmonary abnormalities corresponding to the hot spot on the PET scan. In conclusion, the finding of a lung hot spot in the absence of anatomical abnormality on FDG PET/CT was most likely artifactual or iatrogenic, but it might also represent a real pulmonary lesion. Nonvisualization of anatomical abnormality could be because of its small size and position directly overlying a segmental vessel. Further image follow-up is necessary and important to clarify the nature of the uptake. Copyright © 2017 Elsevier Inc. All rights reserved.

Hybrid SPECT/CT imaging in neurology.

PubMed

Ciarmiello, Andrea; Giovannini, Elisabetta; Meniconi, Martina; Cuccurullo, Vincenzo; Gaeta, Maria Chiara

2014-01-01

In recent years, the SPECT/CT hybrid modality has led to a rapid development of imaging techniques in nuclear medicine, opening new perspectives for imaging staff and patients as well. However, while, the clinical role of positron emission tomography-computed tomography (PET-CT) is well consolidated, the diffusion and the consequent value of single-photon emission tomography-computed tomography (SPECT-CT) has yet to be weighed, Hence, there is a need for a careful analysis, comparing the "potential" benefits of the hybrid modality with the "established" ones of the standalone machine. The aim of this article is to analyze the impact of this hybrid tool on the diagnosis of diseases of the central nervous system, comparing strengths and weaknesses of both modalities through the use of SWOT analysis.

Stomach metastasis of breast carcinoma mimicking primary gastric neoplasm on fluorodeoxy glucose-positron emission tomography-computed tomography.

PubMed

Joshi, Prathamesh; Lele, Vikram; Jain, Reetu; Khubchandani, Shaila; Sinhasan, Shraddha

2013-04-01

We present fluorodeoxy glucose positron emission tomography-computed tomography (FDG-PET/CT) findings in a case of breast carcinoma. The PET/CT findings in this case were suspicious of second primary neoplasm in the stomach. However, on endoscopic biopsy, the lesion was found to be stomach metastasis of breast carcinoma with estrogen receptor positivity. Stomach is a rare site of breast carcinoma metastasis. Our case suggests that it is difficult to distinguish a stomach metastasis of breast cancer from a primary gastric cancer on the basis of clinical and imaging features. However, this differential diagnosis must be kept in mind and it is important to make such distinction because of its implications on patient management.

Performance dependence of hybrid x-ray computed tomography/fluorescence molecular tomography on the optical forward problem.

PubMed

Hyde, Damon; Schulz, Ralf; Brooks, Dana; Miller, Eric; Ntziachristos, Vasilis

2009-04-01

Hybrid imaging systems combining x-ray computed tomography (CT) and fluorescence tomography can improve fluorescence imaging performance by incorporating anatomical x-ray CT information into the optical inversion problem. While the use of image priors has been investigated in the past, little is known about the optimal use of forward photon propagation models in hybrid optical systems. In this paper, we explore the impact on reconstruction accuracy of the use of propagation models of varying complexity, specifically in the context of these hybrid imaging systems where significant structural information is known a priori. Our results demonstrate that the use of generically known parameters provides near optimal performance, even when parameter mismatch remains.

Ceramic and polymeric dental onlays evaluated by photo-elasticity, optical coherence tomography, and micro-computed tomography

NASA Astrophysics Data System (ADS)

Sinescu, Cosmin; Negrutiu, Meda; Topala, Florin; Ionita, Ciprian; Negru, Radu; Fabriky, Mihai; Marcauteanu, Corina; Bradu, Adrian; Dobre, George; Marsavina, Liviu; Rominu, Mihai; Podoleanu, Adrian

2011-10-01

Dental onlays are restorations used to repair rear teeth that have a mild to moderate amount of decay. They can also be used to restore teeth that are cracked or fractured if the damage is not severe enough to require a dental crown. The use of onlays requires less tooth reduction than does the use of metal fillings. This allows dentists to conserve more of a patient's natural tooth structure in the treatment process. The aims of this study are to evaluate the biomechanical comportment of the dental onlays, by using the 3D photo elasticity method and to investigate the integrity of the structures and their fitting to the dental support. For this optical coherence tomography and micro-computed tomography were employed. Both methods were used to investigate 37 dental onlays, 17 integral polymeric and 20 integral ceramic. The results permit to observe materials defects inside the ceramic or polymeric onlays situate in the biomechanically tensioned areas that could lead to fracture of the prosthetic structure. Marginal fitting problems of the onlays related to the teeth preparations were presented in order to observe the possibility of secondary cavities. The resulted images from the optical coherence tomography were verified by the micro-computed tomography. In conclusion, the optical coherence tomography can be used as a clinical method in order to evaluate the integrity of the dental ceramic and polymeric onlays and to investigate the quality of the marginal fitting to the teeth preparations.

Framework for cognitive analysis of dynamic perfusion computed tomography with visualization of large volumetric data

NASA Astrophysics Data System (ADS)

Hachaj, Tomasz; Ogiela, Marek R.

2012-10-01

The proposed framework for cognitive analysis of perfusion computed tomography images is a fusion of image processing, pattern recognition, and image analysis procedures. The output data of the algorithm consists of: regions of perfusion abnormalities, anatomy atlas description of brain tissues, measures of perfusion parameters, and prognosis for infracted tissues. That information is superimposed onto volumetric computed tomography data and displayed to radiologists. Our rendering algorithm enables rendering large volumes on off-the-shelf hardware. This portability of rendering solution is very important because our framework can be run without using expensive dedicated hardware. The other important factors are theoretically unlimited size of rendered volume and possibility of trading of image quality for rendering speed. Such rendered, high quality visualizations may be further used for intelligent brain perfusion abnormality identification, and computer aided-diagnosis of selected types of pathologies.

Pulmonary infection caused by Mycobacterium kansasii: findings on computed tomography of the chest*

PubMed Central

Mogami, Roberto; Goldenberg, Telma; de Marca, Patricia Gomes Cytrangulo; Mello, Fernanda Carvalho de Queiroz; Lopes, Agnaldo José

2016-01-01

Objective To describe the main tomography findings in patients diagnosed with pulmonary infection caused by Mycobacterium kansasii. Materials and Methods Retrospective study of computed tomography scans of 19 patients with pulmonary infection by M. kansasii. Results Of the 19 patients evaluated, 10 (52.6%) were male and 9 (47.4%) were female. The mean age of the patients was 58 years (range, 33-76 years). Computed tomography findings were as follows: architectural distortion, in 17 patients (89.5%); reticular opacities and bronchiectasis, in 16 (84.2%); cavities, in 14 (73.7%); centrilobular nodules, in 13 (68.4%); small consolidations, in 10 (52.6%); atelectasis and large consolidations, in 9 (47.4%); subpleural blebs and emphysema, in 6 (31.6%); and adenopathy, in 1 (5.3%). Conclusion There was a predominance of cavities, as well as of involvement of the small and large airways. The airway disease was characterized by bronchiectasis and bronchiolitis presenting as centrilobular nodules. PMID:27777472

Comparison of lens- and fiber-coupled CCD detectors for X-ray computed tomography

PubMed Central

Uesugi, K.; Hoshino, M.; Yagi, N.

2011-01-01

X-ray imaging detectors with an identical phosphor and a CCD chip but employing lens- and fiber-coupling between them have been compared. These are designed for X-ray imaging experiments, especially computed tomography, at the medium-length beamline at the SPring-8 synchrotron radiation facility. It was found that the transmittance of light to the CCD is about four times higher in the fiber-coupled detector. The uniformity of response in the lens-coupled detector has a global shading of up to 40%, while pixel-to-pixel variation owing to a chicken-wire pattern was dominant in the fiber-coupled detector. Apart from the higher transmittance, the fiber-coupled detector has a few characteristics that require attention when it is used for computed tomography, which are browning of the fiber, discontinuity in the image, image distortion, and dark spots in the chicken-wire pattern. Thus, it is most suitable for high-speed tomography of samples that tend to deform, for example biological and soft materials. PMID:21335908

Emission Computed Tomography: A New Technique for the Quantitative Physiologic Study of Brain and Heart in Vivo

DOE R&D Accomplishments Database

Phelps, M. E.; Hoffman, E. J.; Huang, S. C.; Schelbert, H. R.; Kuhl, D. E.

1978-01-01

Emission computed tomography can provide a quantitative in vivo measurement of regional tissue radionuclide tracer concentrations. This facility when combined with physiologic models and radioactively labeled physiologic tracers that behave in a predictable manner allow measurement of a wide variety of physiologic variables. This integrated technique has been referred to as Physiologic Tomography (PT). PT requires labeled compounds which trace physiologic processes in a known and predictable manner, and physiologic models which are appropriately formulated and validated to derive physiologic variables from ECT data. In order to effectively achieve this goal, PT requires an ECT system that is capable of performing truly quantitative or analytical measurements of tissue tracer concentrations and which has been well characterized in terms of spatial resolution, sensitivity and signal to noise ratios in the tomographic image. This paper illustrates the capabilities of emission computed tomography and provides examples of physiologic tomography for the regional measurement of cerebral and myocardial metabolic rate for glucose, regional measurement of cerebral blood volume, gated cardiac blood pools and capillary perfusion in brain and heart. Studies on patients with stroke and myocardial ischemia are also presented.

Waste inspection tomography (WIT)

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

Bernardi, R.T.

1996-12-31

WIT is a self-sufficient mobile semitrailer for nondestructive evaluation and nondestructive assay of nuclear waste drums using x-ray and gamma-ray tomography. The recently completed Phase I included the design, fabrication, and initial testing of all WIT subsystems installed on-board the trailer. Initial test results include 2 MeV digital radiography, computed tomography, Anger camera imaging, single photon emission computed tomography, gamma-ray spectroscopy, collimated gamma scanning, and active and passive computed tomography using a 1.4 mCi source of {sup 166}Ho. These techniques were initially demonstrated on a 55-gallon phantom drum with 3 simulated waste matrices of combustibles, heterogeneous metals, and cement usingmore » check sources of gamma active isotopes such as {sup 137}Cs and {sup 133}Ba with 9-250 {mu}Ci activities. Waste matrix identification, isotopic identification, and attenuation-corrected gamma activity determination were demonstrated nondestructively and noninvasively in Phase I. Currently ongoing Phase II involves DOE site field test demonstrations at LLNL, RFETS, and INEL with real nuclear waste drums. Current WIT experience includes 55 gallon drums of cement, graphite, sludge, glass, metals, and combustibles. Thus far WIT has inspected drums with 0-20 gms of {sup 239}Pu.« less

Six-dimensional real and reciprocal space small-angle X-ray scattering tomography

NASA Astrophysics Data System (ADS)

Schaff, Florian; Bech, Martin; Zaslansky, Paul; Jud, Christoph; Liebi, Marianne; Guizar-Sicairos, Manuel; Pfeiffer, Franz

2015-11-01

When used in combination with raster scanning, small-angle X-ray scattering (SAXS) has proven to be a valuable imaging technique of the nanoscale, for example of bone, teeth and brain matter. Although two-dimensional projection imaging has been used to characterize various materials successfully, its three-dimensional extension, SAXS computed tomography, poses substantial challenges, which have yet to be overcome. Previous work using SAXS computed tomography was unable to preserve oriented SAXS signals during reconstruction. Here we present a solution to this problem and obtain a complete SAXS computed tomography, which preserves oriented scattering information. By introducing virtual tomography axes, we take advantage of the two-dimensional SAXS information recorded on an area detector and use it to reconstruct the full three-dimensional scattering distribution in reciprocal space for each voxel of the three-dimensional object in real space. The presented method could be of interest for a combined six-dimensional real and reciprocal space characterization of mesoscopic materials with hierarchically structured features with length scales ranging from a few nanometres to a few millimetres—for example, biomaterials such as bone or teeth, or functional materials such as fuel-cell or battery components.

Six-dimensional real and reciprocal space small-angle X-ray scattering tomography.

PubMed

Schaff, Florian; Bech, Martin; Zaslansky, Paul; Jud, Christoph; Liebi, Marianne; Guizar-Sicairos, Manuel; Pfeiffer, Franz

2015-11-19

When used in combination with raster scanning, small-angle X-ray scattering (SAXS) has proven to be a valuable imaging technique of the nanoscale, for example of bone, teeth and brain matter. Although two-dimensional projection imaging has been used to characterize various materials successfully, its three-dimensional extension, SAXS computed tomography, poses substantial challenges, which have yet to be overcome. Previous work using SAXS computed tomography was unable to preserve oriented SAXS signals during reconstruction. Here we present a solution to this problem and obtain a complete SAXS computed tomography, which preserves oriented scattering information. By introducing virtual tomography axes, we take advantage of the two-dimensional SAXS information recorded on an area detector and use it to reconstruct the full three-dimensional scattering distribution in reciprocal space for each voxel of the three-dimensional object in real space. The presented method could be of interest for a combined six-dimensional real and reciprocal space characterization of mesoscopic materials with hierarchically structured features with length scales ranging from a few nanometres to a few millimetres--for example, biomaterials such as bone or teeth, or functional materials such as fuel-cell or battery components.

Computed Tomographic Blend Sign Is Associated With Computed Tomographic Angiography Spot Sign and Predicts Secondary Neurological Deterioration After Intracerebral Hemorrhage.

PubMed

Sporns, Peter B; Schwake, Michael; Schmidt, Rene; Kemmling, André; Minnerup, Jens; Schwindt, Wolfram; Cnyrim, Christian; Zoubi, Tarek; Heindel, Walter; Niederstadt, Thomas; Hanning, Uta

2017-01-01

Significant early hematoma growth in patients with intracerebral hemorrhage is an independent predictor of poor functional outcome. Recently, the novel blend sign (BS) has been introduced as a new imaging sign for predicting hematoma growth in noncontrast computed tomography. Another parameter predicting increasing hematoma size is the well-established spot sign (SS) visible in computed tomographic angiography. We, therefore, aimed to clarify the association between established SS and novel BS and their values predicting a secondary neurological deterioration. Retrospective study inclusion criteria were (1) spontaneous intracerebral hemorrhage confirmed on noncontrast computed tomography and (2) noncontrast computed tomography and computed tomographic angiography performed on admission within 6 hours after onset of symptoms. We defined a binary outcome (secondary neurological deterioration versus no secondary deterioration). As secondary neurological deterioration, we defined (1) early hemicraniectomy under standardized criteria or (2) secondary decrease of Glasgow Coma Scale of >3 points, both within the first 48 hours after symptom onset. Of 182 patients with spontaneous intracerebral hemorrhage, 37 (20.3%) presented with BS and 39 (21.4%) with SS. Of the 81 patients with secondary deterioration, 31 (38.3%) had BS and SS on admission. Multivariable logistic regression analysis identified hematoma volume (odds ratio, 1.07 per mL; P≤0.001), intraventricular hemorrhage (odds ratio, 3.08; P=0.008), and the presence of BS (odds ratio, 11.47; P≤0.001) as independent predictors of neurological deterioration. The BS, which is obtainable in noncontrast computed tomography, shows a high correlation with the computed tomographic angiography SS and is a reliable predictor of secondary neurological deterioration after spontaneous intracerebral hemorrhage. © 2016 American Heart Association, Inc.

Imaging of the thyroid in benign and malignant disease.

PubMed

Intenzo, Charles M; Dam, Hung Q; Manzone, Timothy A; Kim, Sung M

2012-01-01

The thyroid gland was one of the first organs imaged in nuclear medicine, beginning in the 1940s. Thyroid scintigraphy is based on a specific phase or prelude to thyroid hormone synthesis, namely trapping of iodide or iodide analogues (ie, Tc99m pertechnetate), and in the case of radioactive iodine, eventual incorporation into thyroid hormone synthesis within the thyroid follicle. Moreover, thyroid scintigraphy is a reflection of the functional state of the gland, as well as the physiological state of any structure (ie, nodule) within the gland. Scintigraphy, therefore, provides information that anatomical imaging (ie, ultrasound, computed tomography [CT], magnetic resonance imaging) lacks. Thyroid scintigraphy plays an essential role in the management of patients with benign or malignant thyroid disease. In the former, the structure or architecture of the gland is best demonstrated by anatomical or cross-sectional imaging, such as ultrasound, CT, or even magnetic resonance imaging. The role of scintigraphy, however, is to display the functional state of the thyroid gland or that of a clinically palpable nodule within the gland. Such information is most useful in (1) patients with thyrotoxicosis, and (2) those patients whose thyroid nodules would not require tissue sampling if their nodules are hyperfunctioning. In neoplastic thyroid disease, thyroid scintigraphy is often standard of care for postthyroidectomy remnant evaluation and in subsequent thyroid cancer surveillance. Planar radioiodine imaging, in the form of the whole-body scan (WBS) and posttherapy scan (PTS), is a fundamental tool in differentiated thyroid cancer management. Continued controversy remains over the utility of WBS in a variety of patient risk groups and clinical scenarios. Proponents on both sides of the arguments compare WBS with PTS, thyroglobulin, and other imaging modalities with differing results. The paucity of large, randomized, prospective studies results in dependence on consensus expert opinion and retrospective analysis with inherent bias. With a growing trend not to ablate low-risk patients, so that a PTS cannot be performed, some thyroid carcinoma patients may never have radioiodine imaging. In routine clinical practice, however, imaging plays a critical role in patient management both before and after treatment. Moreover, as evidenced by the robust flow of publications concerning WBS and PTS, planar imaging of thyroid carcinoma remains a topic of great interest in this modern age of rapidly advancing cross sectional and hybrid imaging with single-photon emission computed tomography, single-photon emission computed tomography/CT, and positron emission tomography/CT. Copyright © 2012. Published by Elsevier Inc.

Usefulness of 64-detector computed tomography in the diagnosis and management of patients with congenital heart disease.

PubMed

Bret-Zurita, Montserrat; Cuesta, Emilio; Cartón, Antonio; Díez, Jesús; Aroca, Ángel; Oliver, José M; Gutiérrez-Larraya, Federico

2014-11-01

Although congenital heart defects are the most common major congenital abnormalities, the associated mortality has been decreasing due to improvements in their diagnosis and treatment. We assessed the usefulness of 64-multidetector computed tomography in the diagnosis and management of these patients. This 5-year observational, analytical, retrospective, cohort study included a total of 222 tomographic studies of patients with congenital heart disease. Computed tomography scans were read twice and medical records were reviewed. We assessed the complexity of the disease, patient, and radiological technique, and evaluated the contribution of new data in relation to clinical suspicion and diagnostic change. A confidence interval was set at 95% and a P value of<.05 was used as the cutoff for statistical significance. In 35.1% of patients, the treatment procedure was performed after computed tomography without other tests. Additional diagnostic catheterization was performed in 12.5% of patients. There were new findings in 77% of patients (82.9% with complex disease), which prompted a change in patient management in 35.6%. All unexpected reports described new findings. No significant differences were found by age, sex, study period, urgency of the test order, patient complexity, or difficulty of the technique. Use of 64-detector computed tomography yields good diagnostic performance in congenital heart disease, prompts changes in management in more than one-third of patients, and reveals new findings in relation to the presumed diagnosis in 77% of patients. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Diagnostic accuracy of oblique chest radiograph for occult pneumothorax: comparison with ultrasonography.

PubMed

Matsumoto, Shokei; Sekine, Kazuhiko; Funabiki, Tomohiro; Orita, Tomohiko; Shimizu, Masayuki; Hayashida, Kei; Kazamaki, Taku; Suzuki, Tatsuya; Kishikawa, Masanobu; Yamazaki, Motoyasu; Kitano, Mitsuhide

2016-01-01

An occult pneumothorax is a pneumothorax that is not seen on a supine chest X-ray but is detected by computed tomography scanning. However, critical patients are difficult to transport to the computed tomography suite. We previously reported a method to detect occult pneumothorax using oblique chest radiography (OXR). Several authors have also reported that ultrasonography is an effective technique for detecting occult pneumothorax. The aim of this study was to evaluate the usefulness of OXR in the diagnosis of the occult pneumothorax and to compare OXR with ultrasonography. All consecutive blunt chest trauma patients with clinically suspected pneumothorax on arrival at the emergency department were prospectively included at our tertiary-care center. The patients underwent OXR and ultrasonography, and underwent computed tomography scans as the gold standard. Occult pneumothorax size on computed tomography was classified as minuscule, anterior, or anterolateral. One hundred and fifty-nine patients were enrolled. Of the 70 occult pneumothoraces found in the 318 thoraces, 19 were minuscule, 32 were anterior, and 19 were anterolateral. The sensitivity and specificity of OXR for detecting occult pneumothorax was 61.4 % and 99.2 %, respectively. The sensitivity and specificity of lung ultrasonography was 62.9 % and 98.8 %, respectively. Among 27 occult pneumothoraces that could not be detected by OXR, 16 were minuscule and 21 could be conservatively managed without thoracostomy. OXR appears to be as good method as lung ultrasonography in the detection of large occult pneumothorax. In trauma patients who are difficult to transfer to computed tomography scan, OXR may be effective at detecting occult pneumothorax with a risk of progression.

Use of computed tomography and radiolabeled leukocytes in a cat with pancreatitis.

PubMed

Head, Laurie L; Daniel, Gregory B; Becker, Timothy J; Lidbetter, David A

2005-01-01

The normal feline pancreas has been evaluated using radiolabeled leukocytes (99mTc-HMPAO) and computed tomography. The purpose of this report is to describe a clinical case where both modalities were utilized to assess the inflamed feline pancreas. A nine year old female cat presented with anorexia, depression and some vomiting. Blood values were unremarkable. Radiographs and ultrasound were suggestive of pancreatitis. The cat's leukocytes were separated and labeled according to an established protocol. Whole body images were acquired immediately, at 5 and 30 min, and at 1, 2, 4, and 17 hours post injection. Approximately 48 h later, the animal was anesthetized and computed tomography of the abdomen was preformed both pre and post contrast. Surgical biopsies were taken. The distribution of the WBCs was similar to that documented in normal animals, however, at 2 h there was faint uptake seen in the region of the pancreas. This uptake became more intense at 4 h and persisted at 17 h. Computed tomography showed irregular margination of the pancreas, it was larger than normal and inhomogeneous. Contrast enhancement was inhomogeneous and its peak enhancement was not reached until 10 min post injection; normal feline pancreas enhances homogeneously and peaks immediately. Histopathology confirmed pancreatitis with lymphocytic, plasmacytic, neutrophilic and eosinophilic inflammation and fibrosis. Radiolabeled leukocytes can be used to document pancreatic inflammation and this is best seen 4 h after injection. Computed tomography allows superior visualization of the pancreas. Both the appearance and contrast enhancement pattern of the inflamed pancreas differ from normal.

Computed Tomography Assessment of Hepatic Metastases of Breast Cancer with Revised Response Evaluation Criteria in Solid Tumors (RECIST) Criteria (Version 1.1): Inter-Observer Agreement.

PubMed

Ghobrial, Fady Emil Ibrahim; Eldin, Manal Salah; Razek, Ahmed Abdel Khalek Abdel; Atwan, Nadia Ibrahim; Shamaa, Sameh Sayed Ahmed

2017-01-01

To assess inter-observer agreement of revised RECIST criteria (version 1.1) for computed tomography assessment of hepatic metastases of breast cancer. A prospective study was conducted in 28 female patients with breast cancer and with at least one measurable metastatic lesion in the liver that was treated with 3 cycles of anthracycline-based chemotherapy. All patients underwent computed tomography of the abdomen with 64-row multi- detector CT at baseline and after 3 cycles of chemotherapy for response assessment. Image analysis was performed by 2 observers, based on the RECIST criteria (version 1.1). Computed tomography revealed partial response of hepatic metastases in 7 patients (25%) by one observer and in 10 patients (35.7%) by the other observer, with good inter-observer agreement (k=0.75, percent agreement of 89.29%). Stable disease was detected in 19 patients (67.8%) by one observer and in 16 patients (57.1%) by the other observer, with good agreement (k=0.774, percent agreement of 89.29%). Progressive disease was detected in 2 patients (7.2%) by both observers, with perfect agreement (k=1, percent agreement of 100%). The overall inter-observer agreement in the CT-based response assessment of hepatic metastasis between the two observers was good ( k =0.793, percent agreement of 89.29%). We concluded that computed tomography is a reliable and reproducible imaging modality for response assessment of hepatic metastases of breast cancer according to the RECIST criteria (version 1.1).

SU-E-P-10: Establishment of Local Diagnostic Reference Levels of Routine Exam in Computed Tomography

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

Yeh, M; Wang, Y; Weng, H

Introduction National diagnostic reference levels (NDRLs) can be used as a reference dose of radiological examination can provide radiation dose as the basis of patient dose optimization. Local diagnostic reference levels (LDRLs) by periodically view and check doses, more efficiency to improve the way of examination. Therefore, the important first step is establishing a diagnostic reference level. Computed Tomography in Taiwan had been built up the radiation dose limit value,in addition, many studies report shows that CT scan contributed most of the radiation dose in different medical. Therefore, this study was mainly to let everyone understand DRL’s international status. Formore » computed tomography in our hospital to establish diagnostic reference levels. Methods and Materials: There are two clinical CT scanners (a Toshiba Aquilion and a Siemens Sensation) were performed in this study. For CT examinations the basic recommended dosimetric quantity is the Computed Tomography Dose Index (CTDI). Each exam each different body part, we collect 10 patients at least. Carried out the routine examinations, and all exposure parameters have been collected and the corresponding CTDIv and DLP values have been determined. Results: The majority of patients (75%) were between 60–70 Kg of body weight. There are 25 examinations in this study. Table 1 shows the LDRL of each CT routine examination. Conclusions: Therefore, this study would like to let everyone know DRL’s international status, but also establishment of computed tomography of the local reference levels for our hospital, and providing radiation reference, as a basis for optimizing patient dose.« less

Computed tomographic angiography in stroke imaging: fundamental principles, pathologic findings, and common pitfalls.

PubMed

Gupta, Rajiv; Jones, Stephen E; Mooyaart, Eline A Q; Pomerantz, Stuart R

2006-06-01

The development of multidetector row computed tomography (MDCT) now permits visualization of the entire vascular tree that is relevant for the management of stroke within 15 seconds. Advances in MDCT have brought computed tomography angiography (CTA) to the frontline in evaluation of stroke. CTA is a rapid and noninvasive modality for evaluating the neurovasculature. This article describes the role of CTA in the management of stroke. Fundamentals of contrast delivery, common pathologic findings, artifacts, and pitfalls in CTA interpretation are discussed.

Corkscrew basilar artery as an incidental finding on neuroimaging.

PubMed

Moser, Franklin G; Sarnat, Harvey B; Maya, Marcel M; Menkes, John H

2007-11-01

We report on an incidental finding of a markedly tortuous basilar artery in a 6-year-old child. The child underwent a computed tomography scan for minor head trauma, and a basilar artery abnormality was discovered, i.e., a markedly tortuous basilar artery without any other congenital anomalies or syndromes. After an exhaustive workup including computed tomography, magnetic resonance imaging, magnetic resonance angiography, computed tomographic angiography, and genetic tests for associated genetic syndromes, no intervention was deemed necessary. The embryonic etiology and clinical implications are discussed.

[Analysis of single-photon emission computed tomography in patients with hypertensive encephalopathy complicated with previous hypertensive crisis].

PubMed

Kustkova, H S

2012-01-01

In cerebrovascular diseases pefuzionnaya single photon emission computed tomography with lipophilic amines used for the diagnosis of functional disorders of cerebral blood flow. Quantitative calculations helps clarify the nature of vascular disease and clarify the adequacy and effectiveness of the treatment. In this modern program for SPECT ensure conduct not only as to the calculation of blood flow, but also make it possible to compute also the absolute values of cerebral blood flow.

Computed tomography: Will the slices reveal the truth

PubMed Central

Haridas, Harish; Mohan, Abarajithan; Papisetti, Sravanthi; Ealla, Kranti K. R.

2016-01-01

With the advances in the field of imaging sciences, new methods have been developed in dental radiology. These include digital radiography, density analyzing methods, cone beam computed tomography (CBCT), magnetic resonance imaging, ultrasound, and nuclear imaging techniques, which provide high-resolution detailed images of oral structures. The current review aims to critically elaborate the use of CBCT in endodontics. PMID:27652253

Vertical Root Fracture Detection Using Limited-FOV Cone-Beam Computed Tomography

DTIC Science & Technology

2012-06-01

A thesis submitted to the Faculty of the Endodontics Graduate Program Naval Postgraduate Dental School Uniformed Services...Dental Program Navy Medicine Professional Development Center Terry D. Webb, DDS, MS CAPT, DC, USN Chairman, Endodontics Dept. Glen M. Imamura, S...Computed Tomography Geoffrey McMurray, DDS, MS ABSTRACT Introduction: Vertical root fractures (VRF) often occur in endodontically treated teeth

Coronary imaging of anomalous origins and aneurysms of the left coronary artery by multislice computed tomography.

PubMed

Castorina, Sergio; Luca, Tonia; Privitera, Giovanna; Riccioli, Vincenzo

2010-01-01

In this paper, we describe two cases of anomalous origin of the left coronary artery and two cases of aneurysm on the left coronary artery. Detailed three-dimensional images were acquired by the multislice computed tomography (MSCT) SOMATOM Sensation Cardiac 64 during clinical studies of cardiac diseases. Copyright 2010. Published by Elsevier Inc.

Progress in analysis of computed tomography (CT) images of hardwood logs for defect detection

Treesearch

Erol Sarigul; A. Lynn Abbott; Daniel L. Schmoldt

2003-01-01

This paper addresses the problem of automatically detecting internal defects in logs using computed tomography (CT) images. The overall purpose is to assist in breakdown optimization. Several studies have shown that the commercial value of resulting boards can be increased substantially if defect locations are known in advance, and if this information is used to make...

Computed tomography diagnosis of a thoracic and abdominal penetrating foreign body in a dog

PubMed Central

Appleby, Ryan; zur Linden, Alex; Singh, Ameet; Finck, Cyrielle; Crawford, Evan

2015-01-01

A 1.5-year-old, spayed female, mixed-breed dog was presented for hemoabdomen associated with an abdominal mass. Upon presentation bicavitary effusion was diagnosed. A penetrating intra-abdominal wooden foreign body was identified using computed tomography. This case describes a thoracic penetrating wooden foreign body causing bicavitary effusion following migration into the retroperitoneal space. PMID:26538669

Three-Dimensional Printing of X-Ray Computed Tomography Datasets with Multiple Materials Using Open-Source Data Processing

ERIC Educational Resources Information Center

Sander, Ian M.; McGoldrick, Matthew T.; Helms, My N.; Betts, Aislinn; van Avermaete, Anthony; Owers, Elizabeth; Doney, Evan; Liepert, Taimi; Niebur, Glen; Liepert, Douglas; Leevy, W. Matthew

2017-01-01

Advances in three-dimensional (3D) printing allow for digital files to be turned into a "printed" physical product. For example, complex anatomical models derived from clinical or pre-clinical X-ray computed tomography (CT) data of patients or research specimens can be constructed using various printable materials. Although 3D printing…

Comparison of Computed Tomography and Chest Radiography in the Detection of Rib Fractures in Abused Infants

ERIC Educational Resources Information Center

Wootton-Gorges, Sandra L.; Stein-Wexler, Rebecca; Walton, John W.; Rosas, Angela J.; Coulter, Kevin P.; Rogers, Kristen K.

2008-01-01

Purpose: Chest radiographs (CXR) are the standard method for evaluating rib fractures in abused infants. Computed tomography (CT) is a sensitive method to detect rib fractures. The purpose of this study was to compare CT and CXR in the evaluation of rib fractures in abused infants. Methods: This retrospective study included all 12 abused infants…

Association between diabetes and different components of coronary atherosclerotic plaque burden as measured by coronary multidetector computed tomography.

PubMed

Yun, Chun-Ho; Schlett, Christopher L; Rogers, Ian S; Truong, Quynh A; Toepker, Michael; Donnelly, Patrick; Brady, Thomas J; Hoffmann, Udo; Bamberg, Fabian

2009-08-01

The aim of the study was to assess differences in the presence, extent, and composition of coronary atherosclerotic plaque burden as detected by coronary multidetector computed tomography (MDCT) between patients with and without diabetes mellitus. We compared coronary atherosclerotic plaques (any plaque, calcified [CAP], non-calcified [NCAP, and mixed plaque [MCAP

Influence of the Pixel Sizes of Reference Computed Tomography on Single-photon Emission Computed Tomography Image Reconstruction Using Conjugate-gradient Algorithm.

PubMed

Okuda, Kyohei; Sakimoto, Shota; Fujii, Susumu; Ida, Tomonobu; Moriyama, Shigeru

The frame-of-reference using computed-tomography (CT) coordinate system on single-photon emission computed tomography (SPECT) reconstruction is one of the advanced characteristics of the xSPECT reconstruction system. The aim of this study was to reveal the influence of the high-resolution frame-of-reference on the xSPECT reconstruction. 99m Tc line-source phantom and National Electrical Manufacturers Association (NEMA) image quality phantom were scanned using the SPECT/CT system. xSPECT reconstructions were performed with the reference CT images in different sizes of the display field-of-view (DFOV) and pixel. The pixel sizes of the reconstructed xSPECT images were close to 2.4 mm, which is acquired as originally projection data, even if the reference CT resolution was varied. The full width at half maximum (FWHM) of the line-source, absolute recovery coefficient, and background variability of image quality phantom were independent on the sizes of DFOV in the reference CT images. The results of this study revealed that the image quality of the reconstructed xSPECT images is not influenced by the resolution of frame-of-reference on SPECT reconstruction.

Comparison of hand and semiautomatic tracing methods for creating maxillofacial artificial organs using sequences of computed tomography (CT) and cone beam computed tomography (CBCT) images.

PubMed

Szabo, Bence T; Aksoy, Seçil; Repassy, Gabor; Csomo, Krisztian; Dobo-Nagy, Csaba; Orhan, Kaan

2017-06-09

The aim of this study was to compare the paranasal sinus volumes obtained by manual and semiautomatic imaging software programs using both CT and CBCT imaging. 121 computed tomography (CT) and 119 cone beam computed tomography (CBCT) examinations were selected from the databases of the authors' institutes. The Digital Imaging and Communications in Medicine (DICOM) images were imported into 3-dimensonal imaging software, in which hand mode and semiautomatic tracing methods were used to measure the volumes of both maxillary sinuses and the sphenoid sinus. The determined volumetric means were compared to previously published averages. Isometric CBCT-based volume determination results were closer to the real volume conditions, whereas the non-isometric CT-based volume measurements defined coherently lower volumes. By comparing the 2 volume measurement modes, the values gained from hand mode were closer to the literature data. Furthermore, CBCT-based image measurement results corresponded to the known averages. Our results suggest that CBCT images provide reliable volumetric information that can be depended on for artificial organ construction, and which may aid the guidance of the operator prior to or during the intervention.