Comparison of CT and MRI features in sinusitis

International Nuclear Information System (INIS)

Chong, V.F.H.; Fan, Y.F.

1998-01-01

Objective: To correlate the features of inflammatory changes in the paranasal sinuses on magnetic resonance imaging (MRI) with computed tomography (CT). Methods and patients: One hundred and fourteen patients with histologically proven nasopharyngeal carcinoma (NPC) were staged with both CT and MRI. All CT and MRI images of patients with mucosal thickening but no tumour involvement of the sinuses were retrospectively analysed. Results: There were inflammatory changes in 36 maxillary, 21 sphenoid and 16 ethmoid sinuses. These changes include mucosal thickening, retention cysts, retained secretions, inspissated secretions and dystrophic calcification. MRI is superior to CT in separating thickened mucosa, retained secretions and retentions cysts. Conclusion: It is important to appreciate CT changes of sinusitis and the corresponding spectrum of MRI features. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Predicting tumor hypoxia in non-small cell lung cancer by combining CT, FDG PET and dynamic contrast-enhanced CT.

Science.gov (United States)

Even, Aniek J G; Reymen, Bart; La Fontaine, Matthew D; Das, Marco; Jochems, Arthur; Mottaghy, Felix M; Belderbos, José S A; De Ruysscher, Dirk; Lambin, Philippe; van Elmpt, Wouter

2017-11-01

Most solid tumors contain inadequately oxygenated (i.e., hypoxic) regions, which tend to be more aggressive and treatment resistant. Hypoxia PET allows visualization of hypoxia and may enable treatment adaptation. However, hypoxia PET imaging is expensive, time-consuming and not widely available. We aimed to predict hypoxia levels in non-small cell lung cancer (NSCLC) using more easily available imaging modalities: FDG-PET/CT and dynamic contrast-enhanced CT (DCE-CT). For 34 NSCLC patients, included in two clinical trials, hypoxia HX4-PET/CT, planning FDG-PET/CT and DCE-CT scans were acquired before radiotherapy. Scans were non-rigidly registered to the planning CT. Tumor blood flow (BF) and blood volume (BV) were calculated by kinetic analysis of DCE-CT images. Within the gross tumor volume, independent clusters, i.e., supervoxels, were created based on FDG-PET/CT. For each supervoxel, tumor-to-background ratios (TBR) were calculated (median SUV/aorta SUV mean ) for HX4-PET/CT and supervoxel features (median, SD, entropy) for the other modalities. Two random forest models (cross-validated: 10 folds, five repeats) were trained to predict the hypoxia TBR; one based on CT, FDG, BF and BV, and one with only CT and FDG features. Patients were split in a training (trial NCT01024829) and independent test set (trial NCT01210378). For each patient, predicted, and observed hypoxic volumes (HV) (TBR > 1.2) were compared. Fifteen patients (3291 supervoxels) were used for training and 19 patients (1502 supervoxels) for testing. The model with all features (RMSE training: 0.19 ± 0.01, test: 0.27) outperformed the model with only CT and FDG-PET features (RMSE training: 0.20 ± 0.01, test: 0.29). All tumors of the test set were correctly classified as normoxic or hypoxic (HV > 1 cm 3 ) by the best performing model. We created a data-driven methodology to predict hypoxia levels and hypoxia spatial patterns using CT, FDG-PET and DCE-CT features in NSCLC. The

CT imaging and histopathological features of renal epithelioid angiomyolipomas

International Nuclear Information System (INIS)

Cui, L.; Zhang, J.-G.; Hu, X.-Y.; Fang, X.-M.; Lerner, A.; Yao, X.-J.; Zhu, Z.-M.

2012-01-01

Aim: To describe computed tomography (CT) imaging and histopathological manifestations of renal epithelioid angiomyolipomas (EAMLs) for better understanding and cognition in the diagnosis of this new category of renal tumours. Materials and methods: Clinical data and CT images from 10 cases of EAML were retrospectively analysed. All patients underwent CT with and without contrast medium administration, with multiplanar reconstruction (MPR) when needed. Results: Plain CT manifestations of EAMLs were a higher density of mass (10–25 HU) than renal parenchyma, bulging contour of the involved kidney, absence of fat, distinct edges without a lobulate appearance. Contrast-enhanced CT features were markedly heterogeneous enhancement (from rapid wash-in to slow wash-out), large tumour size without lobular appearance, complete capsule with distinct margins and frequent mild necrotic areas. Histopathological features were epithelioid cells with eosinophilic cytoplasm, large and deeply stained nuclei, and dense arrangement of tumour cells with patchy necrosis; diffuse sheets of epithelioid cells were positive for HMB-45 (melanoma-associated antigen) and negative for epithelial membrane antigen (EMA) staining. Conclusion: Multiple specific CT features correlated well with the histopathology and may play an important role in the primary diagnosis of EAMLs.

Less common CT features of medulloblastoma

International Nuclear Information System (INIS)

Zee, C.S; Segall, H.D.; Miller, C.; Ahmad, J.; McComb, J.G.; Han, J.S.; Park, S.H.

1982-01-01

While many medulloblastomas have characteristic features on computed tomography (CT), a significant number have atypical features, including a cystic or necrotic component, calcification, hemorrhage, lack of contrast enhancement, and eccentric location, and/or direct supratentorial extension. Of 30 consecutive untreated cases reviewed by the authors, 14 (47%) had such findings. Failure to make the proper diagnosis will result in some cases if these features are not recognized as possible signs of medulloblastoma

Clinical values of CT and dynamic CT in brain infarction

International Nuclear Information System (INIS)

Lim, Soo Il; Jang, Do; Seo, Eun Joo; Sohn, Myung Hee; Choi, Ki Chul

1985-01-01

With the advent of faster scan time and new computer program, a scanning technique called 'dynamic computed tomography' has become possible. Dynamic computed tomography consisted of performing multiple rapid sequence scans after injection of contrast material. The authors have evaluated the clinical usefulness of computed tomography and dynamic computed tomography of 93 patients with brain infarction and/or ischemia during the period of 17 months from April 1983 to August 1984 in Department of Radiology, Chonbuk National University Hospital. The results were as follows; 1. The age distribution ranged from 18 years to 78 years. Among them the most common age group was between 50 years and 59 years (40.9%). 2. The sites of brain infarction were cerebral lobes (63 cases,68), basal ganglia (15 cases, 16.1%) and multiple sites (6 cases, 6.4%). The common affected site was middle cerebral artery territories. 3. The contrast enhancement of acute infarction was noted in 14 cases (17.5%) which occurred commonly between 3 days and 2 weeks from ictus. 4. The patterns of time-density curve in brain infarction and/or ischemia were as follow: a. Depression of slow wash-in phase was 20 cases (59%). b. Lower peak concentration was 17 cases (50%). c. Lower and delayed peak concentration was 7 cases (21%). d. No definite peak concentration was 6 cases (18%). First three patterns of time-density curve were thought as relatively characteristic curve of brain infarction and/or ischemia. 5. Two cases that showed negative findings on precontrast CT scan appeared to be positive findings as hypodensity on postcontrast CT scan and were confirmed as brain infarction by dynamic CT. 6. The diagnostic entity of dynamic CT scan were as follows; a. large artery thrombotic infarction were 23 cases (58%). b. lacnar infarction were 6 cases (15%). c. ischemia were 5 cases (13%). d. normal were 5 cases (13%). In six cases of lacunar infarction which was double hypodensity on pre-and postcontrast CT

Clinical values of CT and dynamic CT in brain infarction

Energy Technology Data Exchange (ETDEWEB)

Lim, Soo Il; Jang, Do; Seo, Eun Joo; Sohn, Myung Hee; Choi, Ki Chul [Chonbuk National University College of Medicine, Jeonju (Korea, Republic of)

1985-04-15

With the advent of faster scan time and new computer program, a scanning technique called 'dynamic computed tomography' has become possible. Dynamic computed tomography consisted of performing multiple rapid sequence scans after injection of contrast material. The authors have evaluated the clinical usefulness of computed tomography and dynamic computed tomography of 93 patients with brain infarction and/or ischemia during the period of 17 months from April 1983 to August 1984 in Department of Radiology, Chonbuk National University Hospital. The results were as follows; 1. The age distribution ranged from 18 years to 78 years. Among them the most common age group was between 50 years and 59 years (40.9%). 2. The sites of brain infarction were cerebral lobes (63 cases,68), basal ganglia (15 cases, 16.1%) and multiple sites (6 cases, 6.4%). The common affected site was middle cerebral artery territories. 3. The contrast enhancement of acute infarction was noted in 14 cases (17.5%) which occurred commonly between 3 days and 2 weeks from ictus. 4. The patterns of time-density curve in brain infarction and/or ischemia were as follow: a. Depression of slow wash-in phase was 20 cases (59%). b. Lower peak concentration was 17 cases (50%). c. Lower and delayed peak concentration was 7 cases (21%). d. No definite peak concentration was 6 cases (18%). First three patterns of time-density curve were thought as relatively characteristic curve of brain infarction and/or ischemia. 5. Two cases that showed negative findings on precontrast CT scan appeared to be positive findings as hypodensity on postcontrast CT scan and were confirmed as brain infarction by dynamic CT. 6. The diagnostic entity of dynamic CT scan were as follows; a. large artery thrombotic infarction were 23 cases (58%). b. lacnar infarction were 6 cases (15%). c. ischemia were 5 cases (13%). d. normal were 5 cases (13%). In six cases of lacunar infarction which was double hypodensity on pre

Mycoplasma pneumoniae pneumonia: CT features in 16 patients

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Lee, Inho; Kim, Tae Sung; Yoon, Hye-Kyung [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea)

2006-03-15

The objective of this study was to assess the computed tomography (CT) features of Mycoplasma pneumoniae pneumonia. We retrospectively reviewed CT findings of 16 patients (M:F=9:7, age range 1-74 years, median 9 years) with serologically proven Mycoplasma pneumoniae pneumonia and with chest CT scan available. Two distinctive patterns of CT features of M. pneumoniae pneumonia were noted between the paediatric (age <18 years) and the adult (age {>=}18 years) groups. The pediatric group (n=11) showed lobar or segmental consolidation (100%) with frequent pleural effusion (82%) and regional lymphadenopathy (82%) and mild volume decrease of the involved lobe (73%), while four of the five adult patients showed diffuse and/or multifocal, centrilobular or peribronchovascular areas of ground-glass attenuation (80%) with a lobular distribution, and frequent thickening of interlobular septa (60%) and the bronchial walls (40%) were also detected at high-resolution CT. The CT finding of a lobar or segmental consolidation with a parapneumonic effusion seen in our children with M. pneumoniae pneumonia was similar to that of bacterial lobar pneumonia. In contrast, the CT findings noted in our adult patients consisted of a mixture of a bacterial bronchopneumonia pattern and a viral interstitial pneumonia pattern. (orig.)

Mycoplasma pneumoniae pneumonia: CT features in 16 patients

International Nuclear Information System (INIS)

Lee, Inho; Kim, Tae Sung; Yoon, Hye-Kyung

2006-01-01

The objective of this study was to assess the computed tomography (CT) features of Mycoplasma pneumoniae pneumonia. We retrospectively reviewed CT findings of 16 patients (M:F=9:7, age range 1-74 years, median 9 years) with serologically proven Mycoplasma pneumoniae pneumonia and with chest CT scan available. Two distinctive patterns of CT features of M. pneumoniae pneumonia were noted between the paediatric (age <18 years) and the adult (age ≥18 years) groups. The pediatric group (n=11) showed lobar or segmental consolidation (100%) with frequent pleural effusion (82%) and regional lymphadenopathy (82%) and mild volume decrease of the involved lobe (73%), while four of the five adult patients showed diffuse and/or multifocal, centrilobular or peribronchovascular areas of ground-glass attenuation (80%) with a lobular distribution, and frequent thickening of interlobular septa (60%) and the bronchial walls (40%) were also detected at high-resolution CT. The CT finding of a lobar or segmental consolidation with a parapneumonic effusion seen in our children with M. pneumoniae pneumonia was similar to that of bacterial lobar pneumonia. In contrast, the CT findings noted in our adult patients consisted of a mixture of a bacterial bronchopneumonia pattern and a viral interstitial pneumonia pattern. (orig.)

CT features of cardio-pericardial masses

International Nuclear Information System (INIS)

Vasile, N.; Nicoleau, F.; Mathieu, D.

1986-01-01

The results of dynamic computed tomography (CT) in 13 patients with intracardiac filling defects and one with a pericardial lipoma are presented. The intracardiac filling defects were due to thrombus in five cases, myxoma in three, hydatid cysts in three, haemangiopericytoma in one and sarcoma in one. These kinds of lesions are well identified by CT which seems to be superior to echocardiography in the characterisation of the components and in the evaluation of the malignant spreading masses. (orig.)

Dynamic CT in dissecting aortic aneurysm

International Nuclear Information System (INIS)

Fujita, Nobuyuki; Matsuoka, Yosuke; Mizuo, Hideyo; Shirato, Hiroki; Irie, Goro

1985-01-01

especially about the branching of major vessels Eight cases of aortic dissection were analysed to evaluate detectability of the branching of major vessels from a ture or false lumen, by dynamic CT. Although recognition of the branching is easy when the direct continuity to a dissected lumen is demonstrated, but without visualization of direct continuity or with no information about dissected lumens, it is sometimes difficult or leads us to misdiagnosis. The diagnostic accuracy is 100% when direct continuity to a dissected lumen is demonstrated, or dynamic CT revealed branching pattern distinctly. Dynamic CT is useful for a diagnosis of dissecting aneurysm and branching pattern of major vessels. (author)

NMR investigations of structural and dynamics features of natively unstructured drug peptide - salmon calcitonin: implication to rational design of potent sCT analogs.

Science.gov (United States)

Rawat, Atul; Kumar, Dinesh

2013-01-01

Backbone dynamics and conformational properties of drug peptide salmon calcitonin have been studied in aqueous solution using nuclear magnetic resonance (NMR). Although salmon calcitonin (sCT) is largely unfolded in solution (as has been reported in several circular dichroism studies), the secondary H(α) chemical shifts and three bond H(N) -H(α) coupling constants indicated that most of the residues of the peptide are populating the α-helical region of the Ramachandran (ϕ, ψ) map. Further, the peptide in solution has been found to exhibit multiple conformational states exchanging slowly on the NMR timescale (10(2) -10(3)  s(-1) ), inferred by the multiple chemical shift assignments in the region Leu4-Leu12 and around Pro23 (for residues Gln20-Tyr22 and Arg24). Possibly, these slowly exchanging multiple conformational states might inhibit symmetric self-association of the peptide and, in part, may account for its reduced aggregation propensity compared with human calcitonin (which lacks this property). The (15) N NMR-relaxation data revealed (i) the presence of slow (microsecond-to-millisecond) timescale dynamics in the N-terminal region (Cys1-Ser5) and core residues His17 and Asn26 and (ii) the presence of high frequency (nanosecond-to-picosecond) motions in the C-terminal arm. Put together, the various results suggested that (i) the flexible C-terminal of sCT (from Thr25-Thr31) is involved in identification of specific target receptors, (ii) whereas the N-terminal of sCT (from Cys1-Gln20) in solution - exhibiting significant amount of conformational plasticity and strong bias towards biologically active α-helical structure - facilitates favorable conformational adaptations while interacting with the intermembrane domains of these target receptors. Thus, we believe that the structural and dynamics features of sCT presented here will be useful guiding attributes for the rational design of biologically active sCT analogs. Copyright © 2012 European Peptide

Radiotherapy volume delineation using dynamic [18F]-FDG PET/CT imaging in patients with oropharyngeal cancer: a pilot study.

Science.gov (United States)

Silvoniemi, Antti; Din, Mueez U; Suilamo, Sami; Shepherd, Tony; Minn, Heikki

2016-11-01

Delineation of gross tumour volume in 3D is a critical step in the radiotherapy (RT) treatment planning for oropharyngeal cancer (OPC). Static [ 18 F]-FDG PET/CT imaging has been suggested as a method to improve the reproducibility of tumour delineation, but it suffers from low specificity. We undertook this pilot study in which dynamic features in time-activity curves (TACs) of [ 18 F]-FDG PET/CT images were applied to help the discrimination of tumour from inflammation and adjacent normal tissue. Five patients with OPC underwent dynamic [ 18 F]-FDG PET/CT imaging in treatment position. Voxel-by-voxel analysis was performed to evaluate seven dynamic features developed with the knowledge of differences in glucose metabolism in different tissue types and visual inspection of TACs. The Gaussian mixture model and K-means algorithms were used to evaluate the performance of the dynamic features in discriminating tumour voxels compared to the performance of standardized uptake values obtained from static imaging. Some dynamic features showed a trend towards discrimination of different metabolic areas but lack of consistency means that clinical application is not recommended based on these results alone. Impact of inflammatory tissue remains a problem for volume delineation in RT of OPC, but a simple dynamic imaging protocol proved practicable and enabled simple data analysis techniques that show promise for complementing the information in static uptake values.

Dynamic CT in the abdominal organ, 1

International Nuclear Information System (INIS)

Fukuda, Kunihiko

1980-01-01

By utilizing a 4.5-second CT (computed tomography) scanner which allows sequential scans the changes of the iodine concentration in abdominal organs can be observed as dynamics reflected in CT number. The abdominal dynamic CT was performed as following method. After performing the preliminary scan 50ml of 60% meglumine iothalamate was rapidly injected intravenously by hands. The sequential scanning was initiated when a half dose of contrast medium was injected. In completion of the 4 sequential scans under arrested respiration the conventional post contrast scanning was performed. The analysis of 112 cases dynamically studied by CT came to the following conclusion. CT number of the abdominal aorta was greatest on the 1st or 2nd scan of the sequential scans (7.5 - 20.5 seconds after initiation of injection). Following this peak formation, CT number of the abdominal aorta declined rapidly due to both prompt diffusion of contrast medium into the extravascular space and dilution by the intravascular fluid. Iodine concentration of the abdominal aorta during the peak period was calculated as 11.3 mg/ml by the present method, being theoretically sufficient for delineation of the vessels smaller than medium size. In the patients with impaired renal function, several characteristic patterns were noted on the dynamics of contrast medium within the abdominal organs. The abdominal dynamic CT was felt to be promissing for evaluation of the renal function. (author)

Usefulness of multi-plane dynamic subtraction CT (MPDS-CT) for intracranial high density lesions

Energy Technology Data Exchange (ETDEWEB)

Takagi, Ryo; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan)

1996-02-01

We present a new CT technique using the high speed CT scanner in detection and evaluation of temporal and spatial contrast enhancement of intracranial high density lesions. A multi-plane dynamic subtraction CT (MPDS-CT) was performed in 21 patients with intracranial high density lesions. These lesions consisted of 10 brain tumors, 7 intracerebral hemorrhages and 4 vascular malformations (2 untreated, 2 post-embolization). Baseline study was first performed, and 5 sequential planes of covering total high density lesions were selected. After obtaining the 5 sequential CT images as mask images, three series of multi-plane dynamic CT were performed for the same 5 planes with an intravenous bolus injection of contrast medium. MPDS-CT images were reconstructed by subtracting dynamic CT images from the mask ones. MPDS-CT were compared with conventional contrast-enhanced CT. MPDS-CT images showed the definite contrast enhancement of high density brain tumors and vascular malformations which were not clearly identified on conventional contrast-enhanced CT images because of calcified or hemorrhagic lesions and embolic materials, enabling us to eliminate enhanced abnormalities with non-enhanced areas such as unusual intracerebral hemorrhages. MPDS-CT will provide us further accurate and objective information and will be greatly helpful for interpreting pathophysiologic condition. (author).

Computed tomography of hepatocellular carcinoma: Usefulness of dynamic CT

Energy Technology Data Exchange (ETDEWEB)

Takemoto, Kazumasa; Inoue, Yuichi; Matsuoka, Toshiyuki; Nakatsuka, Haruki; Oda, Junro [Osaka City Univ. (Japan). Faculty of Medicine

1983-04-01

Dynamic computed tomography (CT) scans in 65 hepatocellular carcinomas were analyzed and compared to plain and drip infusion contrast CT scans of those. Scans were obtained before, 10, 30, and 50 seconds after an intravenous bolus injection of 50ml 65% Angiografin. By this method, 49 hepatomas had moderate to marked enhancement at the arterial phase while the enhancement of normal liver parenchyma was only slight at the arterial phase and peaked at the portal phase. Compared to a drip infusion contrast CT, a dynamic CT had advantages to detect an isodense hepatoma in 4 and daughter tumors in 16 both of which were not appreciated by a plain and a drip infusion contrast CT. The tumor extension was also better delineated by a dynamic CT because a part of hepatoma had an isodense area. An arterio-portal shunt was visualized in one. Tumor thrombus in the portal vein was clearly demonstrated in 6 at the portal phase of a dynamic CT. Since a dynamic CT is convenient to perform without any special program or soft wear and gives us very useful information, we believe that it should be routinely employed as a part of a liver CT examination.

Dynamic CT in the abdominal organ, 2. Dynamics in the abdominal malignancies

Energy Technology Data Exchange (ETDEWEB)

Fukuda, K [Jikei Univ., Tokyo (Japan). School of Medicine

1980-03-01

The potential role of the abdominal dynamic CT in malignant tumors was evaluated. Among total of 112 cases dynamically studied included were, 22 cases of abdominal malignancies, renal cell carcinoma in 7, hepatocellular carcinoma in 7, metastatic liver tumor in 5, renal pelvic carcinoma in 2, and pancreatic cystadenocarcinoma in one. The results led to the following advantages of the abdominal dynamic CT over conventional CT. (1) The tumor thrombus and the lymphnode involvement could be better demonstrated. (2) The tumor vessels and the tumor stain could be depicted. (3) The extent of the tumor in the parenchyma could be better appreciated. The more invasive catheter angiography would likely to be replaced by the abdominal dynamic CT in the selected case.

Dynamic CT scan in cerebral infarction

International Nuclear Information System (INIS)

Kobayashi, Shigeki; Oka, Nobuo; Mitsuhashi, Hiromitsu

1984-01-01

Forty-two dynamic CT studies were performed on 27 patients with cerebral infarction (11 to 75 years of age), and perfusion patterns of low density areas on plain CT were evaluated. The initial studies were performed 1.5 hours to 60 days after acute onset. The following results were obtained. 1) The perfusion pattern in the low density area on plain CT varies among patients at any periods after onset, ranging from absent perfusion pattern to hyperfusion pattern. No consisitent perfusion pattern was obtained at any given time after onset. 2) Repeat dynamic CT revealed that the perfusion pattern in the low density area changed with time variously. 3) The perfusion pattern or change of perfusion pattern did not correlate with outcome of the patient. 4) At an acute stage, when no abnormal findings were obtained on plain CT, dynamic CT revealed abnormal perfusion pattern, enabling early diagnosis of cerebral infarction and estimation of blood perfusion in the infarcted area. In determining the treatment for the cerebral infarction at an acute stage, it is important to know the condition of the blood perfusion in the infarcted area. For the patients in whom recanalization has already taken place, mannitol or steroid might be effective, providing protection against severe brain edema and hemorrhagic infarction. On the other hand, if recanalization has not taken place, revascularization therapy might be worth trying within 6 hours since the onset. It has been said that ischemic brain damage may not be reversed by the revascularization after 6 hours. Dynamic CT is safe, less invasive, convenient and very useful for early diagnosis of the cerebral infarction and determination of the treatment at the acute stage. (J.P.N.)

Dynamic CT myocardial perfusion imaging

International Nuclear Information System (INIS)

Caruso, Damiano; Eid, Marwen; Schoepf, U. Joseph; Jin, Kwang Nam; Varga-Szemes, Akos; Tesche, Christian; Mangold, Stefanie

2016-01-01

Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

Dynamic CT myocardial perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncological and Pathological Sciences, University of Rome “Sapienza”, Latina (Italy); Eid, Marwen [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul (Korea, Republic of); Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Mangold, Stefanie [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen (Germany); and others

2016-10-15

Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

CT and MR imaging features of mucinous tubular and spindle cell carcinoma of the kidneys. A multi-institutional review

Energy Technology Data Exchange (ETDEWEB)

Cornelis, F.; Grenier, N. [Pellegrin Hospital, Department of Radiology, Bordeaux (France); Ambrosetti, D. [Pasteur Hospital, Department of Pathology, Nice (France); Rocher, L. [Kremlin-Bicetre Hospital, Department of Radiology, Paris (France); Derchi, L.E. [University of Genoa, IRCCS AOU Ospedale, San Martino IST, Department of Health Sciences (DISSAL), Genoa (Italy); Renard, B.; Puech, P. [Claude Huriez Hospital, Department of Radiology, Lille (France); Claudon, M. [Brabois Hospital, Department of Radiology, Vandoeuvre-les-Nancy (France); Rouviere, O. [E. Herriot Hospital, Department of Radiology, Lyon (France); Ferlicot, S. [Kremlin-Bicetre Hospital, Department of Pathology, Paris (France); Roy, C. [Civil Hospital, Department of Radiology, Strasbourg (France); Yacoub, M. [Pellegrin Hospital, Department of Pathology, Bordeaux (France); Bernhard, J.C. [Pellegrin Hospital, Department of Urologic Surgery, Bordeaux (France)

2017-03-15

Mucinous tubular and spindle cell carcinoma (MTSCC) of the kidney is a recently identified renal malignancy. Diagnosis of this rare subtype of renal tumour can be challenging for pathologists, and as such, any additional data would be helpful to improve diagnostic reliability. As imaging features of this new and rare sub-type have not yet been clearly described, the purpose of this study was to describe the main radiologic features on computed tomography (CT) and magnetic resonance imaging (MRI), based jointly on the literature and findings from a multi-institutional retrospective review of pathology and imaging databases. Using a combination of CT/MRI features, diagnosis of MTSCC could be suggested in many cases. A combination of slow enhancement with plateau on dynamic contrast-enhanced CT/MRI, intermediate to high T2 signal intensity contrasting with low apparent diffusion coefficient values on MRI appeared evocative of this diagnosis. (orig.)

CT Features of pseudo tumoral bronchopulmonary tuberculosis

International Nuclear Information System (INIS)

Zidi, A.; Hantoux, S.; Mestiri, I.; Ben Miled-Mrad, K.

2006-01-01

Pulmonary tuberculosis may at times simulate lung carcinoma on bronchoscopic examination or imaging studies. Diagnosis can be delayed and lead to surgical resection. Based on review of 25 cases, the different CT features are reviewed. (author)

Intracranial meningeal masson's hemangioma: CT and angiographic features

International Nuclear Information System (INIS)

Chang, Kee Hyun; Chi, Je Gen; Han, Man Chung; Cho, Byung Kyu; Kim, Hyun Jip

1985-01-01

Masson's hemangioma is a rare benign vascular condition with a papillary intravascular endothelial proliferation which may appear either as a primary form as a secondary form in a pre-existing vascular process. CT and angiographic features of 2 cases with Masson's hemangioma were presented. Both of them were located extra-axially in the posterior fossa. CT findings were not specific in both cases; One showed homogeneously enhancing mass, simulating meningioma. And the other demonstrated a multiocular rim enhancing mass. However, the angiographic features were rather characteristic; Both cases showed persistent vascular poolings of contrast media which were supplied form the meningeal vessels. Angiographic differential diagnosis of similar lesions in the posterior fossa is discussed

Systematic Review and Meta-Analysis of CT Features for Differentiating Complicated and Uncomplicated Appendicitis.

Science.gov (United States)

Kim, Hae Young; Park, Ji Hoon; Lee, Yoon Jin; Lee, Sung Soo; Jeon, Jong-June; Lee, Kyoung Ho

2018-04-01

Purpose To perform a systematic review and meta-analysis to identify computed tomographic (CT) features for differentiating complicated appendicitis in patients suspected of having appendicitis and to summarize their diagnostic accuracy. Materials and Methods Studies on diagnostic accuracy of CT features for differentiating complicated appendicitis (perforated or gangrenous appendicitis) in patients suspected of having appendicitis were searched in Ovid-MEDLINE, EMBASE, and the Cochrane Library. Overlapping descriptors used in different studies to denote the same image finding were subsumed under a single CT feature. Pooled diagnostic accuracy of the CT features was calculated by using a bivariate random effects model. CT features with pooled diagnostic odds ratios with 95% confidence intervals not including 1 were considered as informative. Results Twenty-three studies were included, and 184 overlapping descriptors for various CT findings were subsumed under 14 features. Of these, 10 features were informative for complicated appendicitis. There was a general tendency for these features to show relatively high specificity but low sensitivity. Extraluminal appendicolith, abscess, appendiceal wall enhancement defect, extraluminal air, ileus, periappendiceal fluid collection, ascites, intraluminal air, and intraluminal appendicolith showed pooled specificity greater than 70% (range, 74%-100%), but sensitivity was limited (range, 14%-59%). Periappendiceal fat stranding was the only feature that showed high sensitivity (94%; 95% confidence interval: 86%, 98%) but low specificity (40%; 95% confidence interval, 23%, 60%). Conclusion Ten informative CT features for differentiating complicated appendicitis were identified in this study, nine of which showed high specificity, but low sensitivity. © RSNA, 2017 Online supplemental material is available for this article.

CT features of liver abscesses caused by the fasciola hepatica infection

International Nuclear Information System (INIS)

Fan Dong; Li Peng; Sun Hua; Wang Zhihua; She Bo

2006-01-01

Objective: To study CT features of liver abscesses caused by the fasciola hepatica infection, and discuss its pathologic basis. Methods: CT images of 15 Patients were collected. All patients underwent both unenhanced and biphasic enhanced CT scanning, then its CT performances were analyzed. Results: round and nodular lesions were observed in 15 cases, branching and stripping lesions like dilated bile duct in 9 cases. The density of lesions was inhomogeneous, and the lesions were multifocal and multiform. The liver abscesses caused by the fasciola hepatica infection had no 'rim sign' or 'target' sign, Liver abscesses were less than 3.0 cm in diameter, and the dilation of the bile duct were not observed. Conclusion: Liver abscessed caused by the fasciola hepatica infection have characteristic CT features. Combined with clinical examination and laboratory test, the reliability of diagnosis will be considerably increased. (authors)

Comparison of Dynamic Contrast-Enhanced MRI and PET/CT in the Evaluation of Laryngeal Cancer After Inadequate CT Results

International Nuclear Information System (INIS)

Citil, Serdal; Dogan, Serap; Atilgan, Hasan Ikbal; Menzilcioglu, Mehmet Sait; Sahin, Tuna; Abdulrezzak, Ummuhan; Duymus, Mahmut; Ozturk, Mustafa

2015-01-01

To investigate the diagnostic value of dynamic magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) for laryngeal cancers after inadequate CT results. The study comprised 45 patients investigated for primary laryngeal cancer or recurrence-residue in which CT was considered inadequate. A mass was found in 20 patients. Dynamic MRI and PET/CT were compared for diagnosis of mass, lymph node involvement, recurrence and residue. The dynamic curves formed in dynamic MRI were investigated for diagnostic contributions. The sensitivity and specificity of the dynamic MRI, for supraglottic, glottic and subglottic location, was 100%, 80%, and 92%; 100%, 85%, and 100%, respectively. In PET/CT the sensitivity and specificity were 100% for all of those localizations. For lymph node involvement, the sensitivity of dynamic MRI and PET/CT was 100%, the specificity was 100% and 93%, respectively. For recurrence-residue, the sensitivity and specificity of dynamic MRI were 86% and 67%, respectively, with 100% sensitivity and specificity in PET/CT. The sensitivity of type A curve for detection of malignancy was 40%, and specificity was 100%. When type A and B curves were included, the sensitivity was 100%. For patients investigated for laryngeal cancer in which CT is considered inadequate, dynamic MRI or PET/CT is useful

Comparison of Dynamic Contrast-Enhanced MRI and PET/CT in the Evaluation of Laryngeal Cancer After Inadequate CT Results.

Science.gov (United States)

Citil, Serdal; Dogan, Serap; Atilgan, Hasan Ikbal; Menzilcioglu, Mehmet Sait; Sahin, Tuna; Abdulrezzak, Ummuhan; Duymus, Mahmut; Ozturk, Mustafa

2015-01-01

To investigate the diagnostic value of dynamic magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) for laryngeal cancers after inadequate CT results. The study comprised 45 patients investigated for primary laryngeal cancer or recurrence-residue in which CT was considered inadequate. A mass was found in 20 patients. Dynamic MRI and PET/CT were compared for diagnosis of mass, lymph node involvement, recurrence and residue. The dynamic curves formed in dynamic MRI were investigated for diagnostic contributions. The sensitivity and specificity of the dynamic MRI, for supraglottic, glottic and subglottic location, was 100%, 80%, and 92%; 100%, 85%, and 100%, respectively. In PET/CT the sensitivity and specificity were 100% for all of those localizations. For lymph node involvement, the sensitivity of dynamic MRI and PET/CT was 100%, the specificity was 100% and 93%, respectively. For recurrence-residue, the sensitivity and specificity of dynamic MRI were 86% and 67%, respectively, with 100% sensitivity and specificity in PET/CT. The sensitivity of type A curve for detection of malignancy was 40%, and specificity was 100%. When type A and B curves were included, the sensitivity was 100%. For patients investigated for laryngeal cancer in which CT is considered inadequate, dynamic MRI or PET/CT is useful.

Solitary pulmonary nodules: Comparison of dynamic first-pass contrast-enhanced perfusion area-detector CT, dynamic first-pass contrast-enhanced MR imaging, and FDG PET/CT.

Science.gov (United States)

Ohno, Yoshiharu; Nishio, Mizuho; Koyama, Hisanobu; Seki, Shinichiro; Tsubakimoto, Maho; Fujisawa, Yasuko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

2015-02-01

To prospectively compare the capabilities of dynamic perfusion area-detector computed tomography (CT), dynamic magnetic resonance (MR) imaging, and positron emission tomography (PET) combined with CT (PET/CT) with use of fluorine 18 fluorodeoxyglucose (FDG) for the diagnosis of solitary pulmonary nodules. The institutional review board approved this study, and written informed consent was obtained from each subject. A total of 198 consecutive patients with 218 nodules prospectively underwent dynamic perfusion area-detector CT, dynamic MR imaging, FDG PET/CT, and microbacterial and/or pathologic examinations. Nodules were classified into three groups: malignant nodules (n = 133) and benign nodules with low (n = 53) or high (n = 32) biologic activity. Total perfusion was determined with dual-input maximum slope models at area-detector CT, maximum and slope of enhancement ratio at MR imaging, and maximum standardized uptake value (SUVmax) at PET/CT. Next, all indexes for malignant and benign nodules were compared with the Tukey honest significant difference test. Then, receiver operating characteristic analysis was performed for each index. Finally, sensitivity, specificity, and accuracy were compared with the McNemar test. All indexes showed significant differences between malignant nodules and benign nodules with low biologic activity (P Dynamic perfusion area-detector CT is more specific and accurate than dynamic MR imaging and FDG PET/CT in the diagnosis of solitary pulmonary nodules in routine clinical practice. © RSNA, 2014.

Addison's disease due to adrenal tuberculosis: Contrast-enhanced CT features and clinical duration correlation

International Nuclear Information System (INIS)

Guo Yingkun; Yang Zhigang; Li Yuan; Ma Ensen; Deng Yuping; Min Pengqiu; Yin Longlin; Hu Jian; Zhang Xiaochun; Chen Tianwu

2007-01-01

Purpose: To describe CT morphology of untreated adrenal tuberculosis during the different stages of the natural history of the disease and to evaluate the diagnostic implications of CT features. Materials and methods: We retrospectively evaluated CT features in 42 patients with documented adrenal tuberculosis for the location, size, morphology, and enhancement patterns shown on CT images. The clinical duration were correlated with the CT features. Results: Of the 42 patients with untreated adrenal tuberculosis, bilaterally enlarged adrenal glands were revealed in 38 cases (91%), unilaterally enlarged in 3 cases (7%), and normal size in 1 case (2%). Of the 41 cases (98%) with enlargement, mass-like enlargement was seen in 20 cases (49%) and enlargement with preserved contours in 21 cases (51%). Peripheral rim enhancement presented in 22 cases (52%) on contrast-enhanced CT. Non-enhanced CT scan revealed calcification in 21 cases (50%). As the duration of Addison's disease increased, the presence of calcification and contour preservation increased concomitantly (p < 0.001), whereas peripheral rim enhancement and mass-like enlargement decreased concomitantly on CT images (p < 0.001). Conclusion: CT may be helpful in diagnosing adrenal tuberculosis when clinically suspected, and CT features are correlated to the clinical duration of Addison's disease

CT scanning in pediatric head trauma: correlation of clinical features with CT scan diagnosis

International Nuclear Information System (INIS)

Arkoncel, Mary Ann P.; Posadas, Ma. Belen A.

1997-01-01

A retrospective review was conducted on 205 cases of pediatric head trauma for which cranial computed tomography scans were done at the Makati Medical Center, to determine which clinical features might positively predict an abnormality on CT scan. The clinical findings of loss of consciousness, GCS < 12, vomiting headache, seizures, and focal abnormalities on Neurologic Examination were significantly associated with abnormal findings on CT scan. However, a significant discrepancy does exist as to how accurately clinical findings do in fact predict normal and abnormal CT scan findings. Such a discrepancy allows us to conclude that a more liberal use of CT Scanning in cases of pediatric head trauma must be stressed to insure proper diagnosis. This study shows that when a patient presents with the aforementioned positive signs and symptoms, or with a focal neurologic deficit, or in combination, a 60-100 % positive prediction of abnormal CT Scan can be made. However, prediction of normal CT Scan is only 0-40%. (Author)

Mass-forming chronic pancreatitis : CT and ERCP features

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Jung, Dong Jin; Ha, Hyun Kwon; Lee, Yong Suk; Lee, Jin Hwa; Kim, Pyo Nyun; Lee, Moon Gyu; Auh, Yong Ho [Asan Medical Center, Ulsan Univ. College of Medicine, Ulsan (Korea, Republic of)

1999-11-01

To describe the CT and ERCP findings of mass-forming chronic pancreatitis. CT and ERCP features were assessed in 13 patients suffering from mass-forming chronic pancreatitis. Diagnosis was on the basis of surgery (n=5), percutaneous needle biopsy (n=3), and clinical follow-up (n=5). Contrast-enhanced CT was available for all patients : five underwent dynamic study and ERCP was performed in 12. On CT and ERCP, both groups were evaluated with regard to the presence and degree of pancreatic ductal dilatation (greater or less than 50 % of total gland width), double duct sign, enhancement pattern, pancreatic parenchymal calcification (site and distribution pattern), mass identification, the direction of infiltration, pancreatic parenchymal atrophy, configuration at the site of obstruction in the pancreatic and common bile duct, lymphadenopathy, vascular encasement, and vascular engorgement or increased collateral vessels in the peripancreatic space. Seven of 13 patients had suffered chronic alcoholism. Serum CA19-9 levels were normal in all patients except one. Common CT and ERCP findings of mass-forming chronic pancreatitis included pancreatic duct dilatation (92.3%), double duct sign (69.2%), inhomogeneous enhancement of the mass (69.2%), and the presence of calcification (61.5%). Patterns of pancreatic duct dilation were irregular in five patients (38.4%) and smooth in three (23.1%). In all patients, duct dilatation was less than 50% of total gland width. Enhancement patterns of the pancreatic mass were inhomogeneous (69.2%), a nonenhancing low attenuation mass (15.3%), and homogeneous enhancement (15.3%). Configuration at the site of obstruction in the pancreatic duct was abrupt termination in two patients (15.4%) and smooth termination in two (15.4%). The common bile duct teminated abruptly in three patients (23.1%), and in four (30.8%) smooth narrowing was abserved. Common findings of mass-forming chronic pancreatitis were duct dilatation of less than 50% of total

Mass-forming chronic pancreatitis : CT and ERCP features

International Nuclear Information System (INIS)

Jung, Dong Jin; Ha, Hyun Kwon; Lee, Yong Suk; Lee, Jin Hwa; Kim, Pyo Nyun; Lee, Moon Gyu; Auh, Yong Ho

1999-01-01

To describe the CT and ERCP findings of mass-forming chronic pancreatitis. CT and ERCP features were assessed in 13 patients suffering from mass-forming chronic pancreatitis. Diagnosis was on the basis of surgery (n=5), percutaneous needle biopsy (n=3), and clinical follow-up (n=5). Contrast-enhanced CT was available for all patients : five underwent dynamic study and ERCP was performed in 12. On CT and ERCP, both groups were evaluated with regard to the presence and degree of pancreatic ductal dilatation (greater or less than 50 % of total gland width), double duct sign, enhancement pattern, pancreatic parenchymal calcification (site and distribution pattern), mass identification, the direction of infiltration, pancreatic parenchymal atrophy, configuration at the site of obstruction in the pancreatic and common bile duct, lymphadenopathy, vascular encasement, and vascular engorgement or increased collateral vessels in the peripancreatic space. Seven of 13 patients had suffered chronic alcoholism. Serum CA19-9 levels were normal in all patients except one. Common CT and ERCP findings of mass-forming chronic pancreatitis included pancreatic duct dilatation (92.3%), double duct sign (69.2%), inhomogeneous enhancement of the mass (69.2%), and the presence of calcification (61.5%). Patterns of pancreatic duct dilation were irregular in five patients (38.4%) and smooth in three (23.1%). In all patients, duct dilatation was less than 50% of total gland width. Enhancement patterns of the pancreatic mass were inhomogeneous (69.2%), a nonenhancing low attenuation mass (15.3%), and homogeneous enhancement (15.3%). Configuration at the site of obstruction in the pancreatic duct was abrupt termination in two patients (15.4%) and smooth termination in two (15.4%). The common bile duct teminated abruptly in three patients (23.1%), and in four (30.8%) smooth narrowing was abserved. Common findings of mass-forming chronic pancreatitis were duct dilatation of less than 50% of total

Uncommon adrenal masses: CT and MRI features with histopathologic correlation

International Nuclear Information System (INIS)

Guo Yingkun; Yang Zhigang; Li Yuan; Deng Yuping; Ma Ensen; Min Pengqiu; Zhang Xiaochun

2007-01-01

Adrenal glands are common sites of diseases. With dramatically increased use of computed tomography (CT) and magnetic resonance (MR) imaging, more and more uncommon adrenal masses have been detected incidentally at abdominal examinations performed for other purposes. In this article, uncommon adrenal masses are classified as cystic masses (endothelial cysts, epithelial cysts, parasitic cysts, and pseudocysts), solid masses (ganglioneuroma, ganglioneuroblastoma, extramedullary plasmacytoma (EMP), neurilemmoma, and lymphoma), fat-containing masses (myelolipoma, teratoma), and infectious masses (tuberculoma), and the imaging features of these uncommon masses are demonstrated. Although most of these lesions do not have specific imaging features, some fat-containing masses and cystic lesions present with characteristic appearances, such as myelolipoma, teratoma, and hydatid. Combination with histopathologic characteristic of these uncommon masses of adrenal gland, radiological features of these lesions on CT and MR imaging can be accurately understood with more confidences. Moreover, CT and MRI are highly accurate in localization of uncommon adrenal masses, and useful to guide surgical treatments

Dynamic CT findings of pulmonary hamartoma: A comparison with histopathologic findings

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Cho, Wanglae; Jeong, Yeon Joo; Lee, Chang Hun; Lee, Ji Won; Kim, Yeong Dae [Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan (Korea, Republic of); Kim, Kun Il [Dept. of Radiology, Pusan National University Yangsan Hospital, Pusan National University School of Medicine and Medical Research Institute, Yangsan (Korea, Republic of)

2013-12-15

Describe the dynamic CT findings of pulmonary hamartoma and to compare these findings with histopathologic findings. he Institutional Review Board approved this retrospective study and the requirement for patient informed consent was waived. The hemodynamic CT features of 11 patients (M : F = 6 : 5; mean age, 53.6 years) with pathologically proven pulmonary hamartoma were evaluated. All 11 patients underwent enhanced dynamic CT using a helical technique. A series of images were obtained throughout each nodule with 2.5-mm collimation at 0, 30, 60, 90 and 120 seconds and at 4, 5 and 15 minutes after an intravenous injection of contrast medium. Extents and patterns of enhancement were correlated with histologic tumor components. ll 11 tumors showed persistent enhancement with variable degrees of net enhancement [mean tumor peak enhancement, 48.6 ± 19.0 Hounsfield unit (HU); mean tumor net enhancement, 31.9 ± 11.8 HU] and thick capsular and septal enhancement. Histologically, all 11 tumors were composed of mature cartilage and loose mesenchymal tissue. A significant positive correlation was found between the net enhancement values and loose connective tissue component percentages (r = 0.749, p = 0.008); further, a negative correlation was found between the net enhancement values and cartilaginous component percentages (r = -0.813, p = 0.002). n dynamic CT, hamartoma exhibited persistent enhancement without washout as well as thick capsular and septal enhancements. Net enhancement values were found to be positively correlated with the proportion of the loose connective tissue component. Thick capsular and septal enhancements were attributed histopathologically to loose connective tissue, separating tumors into cartilaginous lobules.

Dynamic CT findings of pulmonary hamartoma: A comparison with histopathologic findings

International Nuclear Information System (INIS)

Cho, Wanglae; Jeong, Yeon Joo; Lee, Chang Hun; Lee, Ji Won; Kim, Yeong Dae; Kim, Kun Il

2013-01-01

Describe the dynamic CT findings of pulmonary hamartoma and to compare these findings with histopathologic findings. he Institutional Review Board approved this retrospective study and the requirement for patient informed consent was waived. The hemodynamic CT features of 11 patients (M : F = 6 : 5; mean age, 53.6 years) with pathologically proven pulmonary hamartoma were evaluated. All 11 patients underwent enhanced dynamic CT using a helical technique. A series of images were obtained throughout each nodule with 2.5-mm collimation at 0, 30, 60, 90 and 120 seconds and at 4, 5 and 15 minutes after an intravenous injection of contrast medium. Extents and patterns of enhancement were correlated with histologic tumor components. ll 11 tumors showed persistent enhancement with variable degrees of net enhancement [mean tumor peak enhancement, 48.6 ± 19.0 Hounsfield unit (HU); mean tumor net enhancement, 31.9 ± 11.8 HU] and thick capsular and septal enhancement. Histologically, all 11 tumors were composed of mature cartilage and loose mesenchymal tissue. A significant positive correlation was found between the net enhancement values and loose connective tissue component percentages (r = 0.749, p = 0.008); further, a negative correlation was found between the net enhancement values and cartilaginous component percentages (r = -0.813, p = 0.002). n dynamic CT, hamartoma exhibited persistent enhancement without washout as well as thick capsular and septal enhancements. Net enhancement values were found to be positively correlated with the proportion of the loose connective tissue component. Thick capsular and septal enhancements were attributed histopathologically to loose connective tissue, separating tumors into cartilaginous lobules.

Budd-Chiari syndrome: dynamic enhancement findings with multi-slice helical CT and CT angiography analysis

International Nuclear Information System (INIS)

Meng Xiaochun; Shan Hong; Zhu Kangshun; Xu Chuan; Zhang Jiansheng; Liu Lingyun; Ye Binbin

2005-01-01

Objective: To investigate the dynamic enhancement regulations of liver and their mechanism in Budd-Chiari syndrome (BCS) by using multi-slice CT and evaluate the value of CT angiography in the diagnosis of BCS. Methods: 28 cases with BCS confirmed by digital subtraction angiography (DSA) were retrospectively analyzed. All patients underwent dynamic enhancement examinations with multi-slice CT within 1 week before DSA. The relevant vessels were reconstructed respectively with MIP, VR and MPR. Compared with the results of DSA, we analyzed the dynamic enhancement regulations of liver in BCS, estimated the value of dynamic enhancement CT exams and CTA techniques in judging the obstruction level and showing collateral vessels. Results: Of all 28 cases, CT correctly showed the obstruction level in 26 cases, and 2 had incorrect results which proved to be membranous obstruction of the inferior vena cava superior to diaphragm. In 22 cases with hepatic vein obstructions, hepatic parenchyma displayed typical patchy enhancement in 19, atypical patchy enhancement in 3.8 cases among these showed benign nodules. Simultaneously, CT showed stenosis and rigidity of portal vein branches in 20, enlargement of hepatic artery in 14, hepatic collateral vessels in 20 out of 22 cases. In 6 cases with simple obstruction of inferior vena cava, hepatic changes were not found. Collateral circulations in or out of liver corresponded to the obstruction level. Conclusion: Dynamic enhancement examinations with multi-slice CT can correctly reflect the hepatic hemodynamic changes. Transverse images, combined with CTA, can explicitly display the obstruction level of vascular lesions and collateral circulations in BCS. (authors)

Advanced gastric cancer. The findings of delayed phase dynamic CT and radiologic-histopathologic correlation

International Nuclear Information System (INIS)

Monzawa, Shuichi; Omata, Kosaku; Nakazima, Hiroto; Yokosuka, Noriko; Ito, Atuko; Araki, Tsutomu

2000-01-01

The aim of this study was to describe delayed phase dynamic CT findings of advanced (T2-T4) gastric cancer and to correlate with histopathologic findings. Quadruple phase dynamic CT including delayed imaging taken five minutes after the start of injection of contrast material was performed in 43 patients with 45 advanced gastric cancer and 20 control subjects with no gastric lesions. On delayed phase CT scans, the attenuation of the gastric wall was equal to or lower than that of the liver parenchyma in the control subjects, therefore, the presence of higher attenuation in the gastric wall was considered to be abnormal and defined as delayed enhancement. Histopathologic findings in the tumors showing delayed enhancement were compared with those in the tumors without this feature. Delayed enhancement was seen in 26 (57%) of the 45 tumors. Eleven of 25 differentiated-type tumors and 15 of 20 undifferentiated-type tumors showed delayed enhancement (p<.05). Delayed enhancement was seen in one of five medullary type tumors, in 11 of 25 intermediate-type tumors, and in 14 of 15 scirrhous-type tumors (p<.005). Delayed enhancement was frequently seen in the tumors with abundant fibrous tissue stroma. Delayed phase dynamic CT may be useful for the characterization of advanced gastric cancer. (author)

Pneumatosis intestinalis: CT findings and clinical features

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Kim, Hye Lin; Lee, Hae Kyung; Park, Seong Jin; Yi, Boem Ha; Ko, Bong Min; Hong, Hyun Sook; Paik, Sang Hyun [Soonchunhyang University Hospital Bucheon, Bucheon (Korea, Republic of)

2008-02-15

The purpose of this study is to evaluate the CT findings and clinical features of patients with pneumatosis intestinalis. From January 2001 to October 2007, 15 patients with pneumatosis intestinalis were diagnosed by the use of CT. We analyzed the clinical features and CT findings to assess the involvement site, the presence of portal and mesenteric vein gas, and the existence of accompanied ischemic change. Of the 15 patients, five patients had end stage renal disease (33.3%), two patients underwent a gastrectomy, one patient underwent a laminectomy, one patient had tuberculous enteritis, one patient had lung cancer and one patient had pneumonia. Four patients presented with no specific disease. There was portal or mesenteric venous gas in six cases, and strangulation or an ischemic change of the bowel in five cases. Otherwise, pneumatosis intestinalis was associated with hydropneumoperitoneum in two cases, pneumoperitoneum in one case and a single case of perforated appendicitis. Nine patients underwent surgery for ischemic change of the bowel, pneumoperitoneum, appendicitis, and a clinical sign of panperitonitis. Among the remaining six patients, three patients recovered and were discharged, and three patients expired during progression of the disease. End stage renal disease is the most common condition associated with pneumatosis intestinalis. The presence of portomesenteric venous gas, ischemic change of the bowel, and linear pneumatosis intestinalis are indicative of a poor prognosis.

Profiles of US and CT imaging features with a high probability of appendicitis

International Nuclear Information System (INIS)

Randen, A. van; Lameris, W.; Es, H.W. van; Hove, W. ten; Bouma, W.H.; Leeuwen, M.S. van; Keulen, E.M. van; Hulst, V.P.M. van der; Henneman, O.D.; Bossuyt, P.M.; Boermeester, M.A.; Stoker, J.

2010-01-01

To identify and evaluate profiles of US and CT features associated with acute appendicitis. Consecutive patients presenting with acute abdominal pain at the emergency department were invited to participate in this study. All patients underwent US and CT. Imaging features known to be associated with appendicitis, and an imaging diagnosis were prospectively recorded by two independent radiologists. A final diagnosis was assigned after 6 months. Associations between appendiceal imaging features and a final diagnosis of appendicitis were evaluated with logistic regression analysis. Appendicitis was assigned to 284 of 942 evaluated patients (30%). All evaluated features were associated with appendicitis. Imaging profiles were created after multivariable logistic regression analysis. Of 147 patients with a thickened appendix, local transducer tenderness and peri-appendiceal fat infiltration on US, 139 (95%) had appendicitis. On CT, 119 patients in whom the appendix was completely visualised, thickened, with peri-appendiceal fat infiltration and appendiceal enhancement, 114 had a final diagnosis of appendicitis (96%). When at least two of these essential features were present on US or CT, sensitivity was 92% (95% CI 89-96%) and 96% (95% CI 93-98%), respectively. Most patients with appendicitis can be categorised within a few imaging profiles on US and CT. When two of the essential features are present the diagnosis of appendicitis can be made accurately. (orig.)

Profiles of US and CT imaging features with a high probability of appendicitis

Energy Technology Data Exchange (ETDEWEB)

Randen, A. van; Lameris, W. [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Surgery, Academic Medical Center, Amsterdam (Netherlands); Es, H.W. van [St Antonius Hospital, Department of Radiology, Nieuwegein (Netherlands); Hove, W. ten; Bouma, W.H. [Gelre Hospitals, Department of Surgery, Apeldoorn (Netherlands); Leeuwen, M.S. van [University Medical Centre, Department of Radiology, Utrecht (Netherlands); Keulen, E.M. van [Tergooi Hospitals, Department of Radiology, Hilversum (Netherlands); Hulst, V.P.M. van der [Onze Lieve Vrouwe Gasthuis, Department of Radiology, Amsterdam (Netherlands); Henneman, O.D. [Bronovo Hospital, Department of Radiology, The Hague (Netherlands); Bossuyt, P.M. [University of Amsterdam, Department of Clinical Epidemiology, Biostatistics, and Bioinformatics, Academic Medical Center, Amsterdam (Netherlands); Boermeester, M.A. [University of Amsterdam, Department of Surgery, Academic Medical Center, Amsterdam (Netherlands); Stoker, J. [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands)

2010-07-15

To identify and evaluate profiles of US and CT features associated with acute appendicitis. Consecutive patients presenting with acute abdominal pain at the emergency department were invited to participate in this study. All patients underwent US and CT. Imaging features known to be associated with appendicitis, and an imaging diagnosis were prospectively recorded by two independent radiologists. A final diagnosis was assigned after 6 months. Associations between appendiceal imaging features and a final diagnosis of appendicitis were evaluated with logistic regression analysis. Appendicitis was assigned to 284 of 942 evaluated patients (30%). All evaluated features were associated with appendicitis. Imaging profiles were created after multivariable logistic regression analysis. Of 147 patients with a thickened appendix, local transducer tenderness and peri-appendiceal fat infiltration on US, 139 (95%) had appendicitis. On CT, 119 patients in whom the appendix was completely visualised, thickened, with peri-appendiceal fat infiltration and appendiceal enhancement, 114 had a final diagnosis of appendicitis (96%). When at least two of these essential features were present on US or CT, sensitivity was 92% (95% CI 89-96%) and 96% (95% CI 93-98%), respectively. Most patients with appendicitis can be categorised within a few imaging profiles on US and CT. When two of the essential features are present the diagnosis of appendicitis can be made accurately. (orig.)

Dynamic helical CT mammography of breast cancer

International Nuclear Information System (INIS)

Yamamoto, Akira; Fukushima, Hitoshi; Okamura, Ryuji; Nakamura, Yoshiaki; Morimoto, Taisuke; Urata, Yoji; Mukaihara, Sumio; Hayakawa, Katsumi

2006-01-01

The purpose of this study was to determine whether dynamic helical computed tomography (CT)-mammography could assist in selecting the most appropriate surgical method in women with breast cancer. Preoperative contrast-enhanced helical CT scanning of the breast was performed on 133 female patients with suspicion of breast cancer at the same time as clinical, mammographic, and/or ultrasonographic examinations. The patients were scanned in the prone position with a specially designed CT-compatible device. A helical scan was made with rapid intravenous bolus injection (3 ml/s) of 100 ml of iodine contrast material. Three-dimensional maximum intensity projection (MIP) images were reconstructed, and CT findings were correlated with surgical and histopathological findings. Histopathological analysis revealed 84 malignant lesions and seven benign lesions. The sensitivity, specificity, and accuracy levels of the CT scanning were 94.6%, 58.6%, and 78.9%. Helical scanning alone revealed additional contralateral carcinomas in three of four patients and additional ipsilateral carcinomas in three of five patients. However, the technique gave false-positive readings in 24 patients. The preoperative CT-mammogram altered the surgical method in six patients. Dynamic helical CT-mammography in the prone position may be one of the choices of adjunct imaging in patients with suspected breast cancer scheduled for surgery. (author)

Acute Appendagitis Presenting with Features of Appendicitis: Value of Abdominal CT Evaluation

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Sukhpreet Dubb

2008-05-01

Full Text Available We report a case of acute appendagitis in a patient who presented initially with typical features of acute appendicitis. The diagnosis of acute appendagitis was made on pathognomonic signs on computed tomography (CT scan. Abdominal pain is a common surgical emergency. CT is not always done if there are clear features of acute appendicitis. The rare but important differential diagnosis of acute appendagitis must be borne in mind when dealing with patients with suspected acute appendicitis. A CT scan of the abdomen may avoid unnecessary surgery in these patients.

Spiral CT features of abdomen after whipple's operation

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Kim, T. H.; Lee, K. Y.; Shin, K. H.; Jung, M. H.; Park, C. M.; Cha, I. H. [Korea Univ. College of Medicine, Seoul (Korea, Republic of)

1997-04-01

To assess the CT features of postoperative anatomical changes, surgical complications, and patterns of tumor recurrence after Whipple's operation. 42 spiral CT scans of 31 patients who had undergone Whipple's operation were retrospectively reviewed. Postoperative diagnoses were distal CBD cancer in 13 patients, cancer of the ampulla of Vater in ten, cancer of the head of the pancreas in seven, and microcystic cystadenocarcinoma of the pancreas in one. Time intervals between surgery and CT ranged from 1 week to 5 years. CT features of postoperative anastomotic changes, surgical complications, and patterns of tumor recurrence were analyzed. Gastro- or duodeno-jejunal anastomosis was seen in 32 CT scans(74%), pancreaticojejunostomy in 27(64%), and choledochojejunostomy in 24(57%). Pneumobilia was seen in ten patients(34%). Abnormal fluid collections in the peripancreatic and perihepatic space were demonstrated in two patients who underwent CT scans within 3 weeks after operation. Other complications included wound abscess(n=2), and portal vein occlusion(n=1). The most common site of metastasis was the lymph node(n=8)(retroperitoneal:n=5; mesentery root:n=4; and celiac:n=2), followed by the liver(n=6), peritoneum(n=3), adrenal gland(n=2), and afferent loop(n=1). In three cases, there was local recurrence in the pancreatic bed. To reduce possible diagnostic errors during CT interpretation, a Knowledge of normal postoperative anatomy, common complications, and patterns of disease recurrence following Whipple's operation is important.

Profiles of US and CT imaging features with a high probability of appendicitis

NARCIS (Netherlands)

van Randen, A.; Laméris, W.; van Es, H.W.; ten Hove, W.; Bouma, W.H.; van Leeuwen, M.S.; van Keulen, E.M.; van der Hulst, V.P.M.; Henneman, O.D.; Bossuyt, P.M.; Boermeester, M.A.; Stoker, J.

2010-01-01

To identify and evaluate profiles of US and CT features associated with acute appendicitis. Consecutive patients presenting with acute abdominal pain at the emergency department were invited to participate in this study. All patients underwent US and CT. Imaging features known to be associated with

CT features of gastric heterotopic pancreas

International Nuclear Information System (INIS)

Wu Guangyao; Tian Zhixiong; Zhang Zaipeng; Huang Xiong

2007-01-01

Objective: To analyze CT findings correlated with pathologic findings in ectopic pancreas of the stomach. Methods: CT scans of 15 surgically proven eases of ectopic pancreas of the stomach were reviewed, and enhanced CT scan was performed in 11 cases. CT findings were correlated with the pathologic findings. Results: All cases had single lesion, and all lesions showed homogeneous density on plain scans without cystic or malignant changes. The size ranged from 1.3 to 3.1 cm, with mean diameter of (1.9±0.2) cm. The lesions were round or oval in shape with broad base against the gastric wall. Two showed central umbilication sign. Only 2 cases were correctly diagnosed prior to operation and the rest were misdiagnosed or diagnosed indistinctly. The locations were in the gastric antrum in 11 cases, in the body in 3, and in fundus in one; The ectopic pancreas located in the greater curvature in 10, and in the lesser curvature in 5. Homogeneous or inhomogeneous strong enhancement similar to the pancreas was seen in 8 cases and they consisted mainly of pancreatic acini with the same histologic features as the pancreas. Three cases showed poor enhancement and consisted mainly of ducts and hypertrophied muscle, pancreatic acini were a minor component. Conclusion: Ectopic pancreas of the stomach showed characteristic locations with the findings of submucosal diseases. Different enhancing patterns were correlated with their pathologic findings. (authors)

Comparison of CT enterography and MR enterography imaging features of active Crohn disease in children and adolescents

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Gale, Heather I. [The Warren Alpert Medical School of Brown University, Department of Diagnostic Imaging, Rhode Island Hospital/Hasbro Children' s Children' s Hospital/Women and Infants Hospital, Providence, RI (United States); Sharatz, Steven M.; Nimkin, Katherine; Gee, Michael S. [MassGeneral Hospital for Children, Division of Pediatric Imaging, Department of Radiology, Harvard Medical School, Boston, MA (United States); Taphey, Mayureewan [Bumrungrad International Hospital, Bangkok (Thailand); Bradley, William F. [Cambridge Mobile Telematics, Cambridge, MA (United States)

2017-09-15

Assessment for active Crohn disease by CT enterography and MR enterography relies on identifying mural and perienteric imaging features. To evaluate the performance of established imaging features of active Crohn disease in children and adolescents on CT and MR enterography compared with histological reference. We included patients ages 18 years and younger who underwent either CT or MR enterography from 2007 to 2014 and had endoscopic biopsy within 28 days of imaging. Two pediatric radiologists blinded to the histological results reviewed imaging studies and scored the bowel for the presence or absence of mural features (wall thickening >3 mm, mural hyperenhancement) and perienteric features (mesenteric hypervascularity, edema, fibrofatty proliferation and lymphadenopathy) of active disease. We performed univariate analysis and multivariate logistic regression to compare imaging features with histological reference. We evaluated 452 bowel segments (135 from CT enterography, 317 from MR enterography) from 84 patients. Mural imaging features had the highest association with active inflammation both for MR enterography (wall thickening had 80% accuracy, 69% sensitivity and 91% specificity; mural hyperenhancement had 78%, 53% and 96%, respectively) and CT enterography (wall thickening had 84% accuracy, 72% sensitivity and 91% specificity; mural hyperenhancement had 76%, 51% and 91%, respectively), with perienteric imaging features performing significantly worse on MR enterography relative to CT enterography (P < 0.001). Mural features are predictors of active inflammation for both CT and MR enterography, while perienteric features can be distinguished better on CT enterography compared with MR enterography. This likely reflects the increased conspicuity of the mesentery on CT enterography and suggests that mural features are the most reliable imaging features of active Crohn disease in children and adolescents. (orig.)

Clinical analysis of CT features in 200 neonates with hypoxic-ischemic encephalopathy (HIE)

International Nuclear Information System (INIS)

Zhang Fan

2003-01-01

Objective: To analyze the CT features of HIE in neonates. Methods: CT scanning was performed in 200 neonates with HIE. Results: The CT features in 200 HIE were hypo-attenuated substantia alba, accompanied with intra-cranial hemorrhage, widened cavity of septum pellucidum and cerebral infarction. In total 200 cases, mild HIE was found in 118 cases, moderate HIE was revealed in 67 cases and severe condition was observed in 15 cases. Intra-cranial hemorrhage was noted in 87 cases. Conclusion: The cerebral injury should be diagnosed by the findings of hypo-attenuated substantia alba and intracranial hemorrhage on CT scan, combined with clinical histories and manifestations of intro-uterine neonate asphyxia

Post-ischemic bowel stricture: CT features in eight cases

Energy Technology Data Exchange (ETDEWEB)

Kim, Jin Sil [Dept. of Radiology, College of Medicine, Ewha Womans University, Mokdong Hospital, Seoul (Korea, Republic of); Kim, Hyun Jin; Hong, Sung Mo; Park, Seong Ho; Lee, Jong Seok; Kim, Ah Young; Ha, Hyun Kwon [University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

2017-11-15

To investigate the characteristic radiologic features of post-ischemic stricture, which can then be implemented to differentiate that specific disease from other similar bowel diseases, with an emphasis on computed tomography (CT) features. Eight patients with a diagnosis of ischemic bowel disease, who were also diagnosed with post-ischemic stricture on the basis of clinical or pathologic findings, were included. Detailed clinical data was collected from the available electronic medical records. Two radiologists retrospectively reviewed all CT images. Pathologic findings were also analyzed. The mean interval between the diagnosis of ischemic bowel disease and stricture formation was 57 days. The severity of ischemic bowel disease was variable. Most post-ischemic strictures developed in the ileum (n = 5), followed by the colon (n = 2) and then the jejunum (n = 1). All colonic strictures developed in the “watershed zone.” The pathologic features of post-ischemic stricture were deep ulceration, submucosal/subserosal fibrosis and chronic transmural inflammation. The mean length of the post-ischemic stricture was 7.4 cm. All patients in this study possessed one single stricture. On contrast-enhanced CT, most strictures possessed concentric wall thickening (87.5%), with moderate enhancement (87.5%), mucosal enhancement (50%), or higher enhancement in portal phase than arterial phase (66.7%). Post-ischemic strictures develop in the ileum, jejunum and colon after an interval of several weeks. In the colonic segment, strictures mainly occur in the “watershed zone.” Typical CT findings include a single area of concentric wall thickening of medium length (mean, 7.4 cm), with moderate and higher enhancement in portal phase and vasa recta prominence.

Predictive features of CT for risk stratifications in patients with primary gastrointestinal stromal tumour

International Nuclear Information System (INIS)

Zhou, Cuiping; Zhang, Xiang; Duan, Xiaohui; Hu, Huijun; Wang, Dongye; Shen, Jun

2016-01-01

To determine the predictive CT imaging features for risk stratifications in patients with primary gastrointestinal stromal tumours (GISTs). One hundred and twenty-nine patients with histologically confirmed primary GISTs (diameter >2 cm) were enrolled. CT imaging features were reviewed. Tumour risk stratifications were determined according to the 2008 NIH criteria where GISTs were classified into four categories according to the tumour size, location, mitosis count, and tumour rupture. The association between risk stratifications and CT features was analyzed using univariate analysis, followed by multinomial logistic regression and receiver operating characteristic (ROC) curve analysis. CT imaging features including tumour margin, size, shape, tumour growth pattern, direct organ invasion, necrosis, enlarged vessels feeding or draining the mass (EVFDM), lymphadenopathy, and contrast enhancement pattern were associated with the risk stratifications, as determined by univariate analysis (P < 0.05). Only lesion size, growth pattern and EVFDM remained independent risk factors in multinomial logistic regression analysis (OR = 3.480-100.384). ROC curve analysis showed that the area under curve of the obtained multinomial logistic regression model was 0.806 (95 % CI: 0.727-0.885). CT features including lesion size, tumour growth pattern, and EVFDM were predictors of the risk stratifications for GIST. (orig.)

CT features of nonfunctioning islet cell carcinoma

Energy Technology Data Exchange (ETDEWEB)

Eelkema, E.A.; Stephens, D.H.; Ward, E.M.; Sheedy, P.F. II

1984-11-01

To determine the computed tomographic (CT) characteristics of nonfunctioning islet cell carcinoma of the pancreas, the CT scans of 27 patients with that disease were reviewed. The pancreatic tumor was identified as a mass in 26 patients (96%) Of the 25 tumors evaluated with contrast enhancement, 20 became partially diffusely hyperdense relative to nearby normal pancreatic tissue. Hepatic metastases were identified in 15 patients (56%), regional lymphadenopathy in 10 (37%), atrophy of the gland proximal to the tumor in six (22%), dilatation of the biliary ducts in five (19%), and dilatation of the pancreatic duct in four (15%). The CT appearances of the nonfunctioning islet cell tumors were compared with those of 100 ordinary (ductal) pancreatic adenocarcinomas. Although the two types of tumors were sometimes indistinguishable, features found to be more characteristic of islet cell carcinoma included a pancreatic mass of unusually large size, calcification within the tumor, and contrast enhancement of either the primary tumor or hepatic metastases. Involvement of the celiac axis or proximal superior mesenteric artery was limited to ductal carcinoma.

Idiopathic hypereosinophilic syndrome involving the liver: CT features vs. peripheral eosinophilia

Energy Technology Data Exchange (ETDEWEB)

Kim, Kyung Sook; Lee, Moon Gyu; Won, Young Chul; Lee, Eun Hye; Noh, Han Na; Ha, Hyun Kwon; Kim, Pyo Nyun; Auh, Yong Ho [Ulsan Univ. College of Medicine, Seoul (Korea, Republic of)

1997-10-01

To correlate CT features with peripheral eosinophilia in patients with idiopathic hypereosinophilic syndrome involving the liver. During the last three years, features of liver involvement in nine of 20 patients with idiopathic hypereosinophilic syndrome were evaluated on CT. The shape and distribution of intrahepatic low densities and the presence of hepatomegaly and/or splenomegaly were reviewed on CT, and the percentage of eosinophils in peripheral blood was also determined. In seven cases, interval change in hepatic lesion and the percentage of eosinophils were reviewed on follow-up examination. On initial CT, varying low-density patterns were seen in the liver in all cases; hepatomegaly was seen in four cases, and hepatosplenomegaly in two. The percentage of eosinophils was 89% in a case with diffuse patch low densities in the liver, 65-85% in three cases with numerous nodular low density lesions, 12-29% in four cases with multiple (below ten) nodular or small geographic hypodense lesions, and 24% in a case with a single nodular hypodense lesion. On follow-up CT, seven patients showed a decrease in the percentage of eosinophils, and in six, improved intrahepatic low densities were seen. On CT, intrahepatic low densities were seen in patients with idiopathic hypereosinophilic syndrome, and these were distributed more extensively when peripheral eosinophilia was more severe. With improvement in peripheral eosinophilia, the low densities also improved.

Idiopathic hypereosinophilic syndrome involving the liver: CT features vs. peripheral eosinophilia

International Nuclear Information System (INIS)

Kim, Kyung Sook; Lee, Moon Gyu; Won, Young Chul; Lee, Eun Hye; Noh, Han Na; Ha, Hyun Kwon; Kim, Pyo Nyun; Auh, Yong Ho

1997-01-01

To correlate CT features with peripheral eosinophilia in patients with idiopathic hypereosinophilic syndrome involving the liver. During the last three years, features of liver involvement in nine of 20 patients with idiopathic hypereosinophilic syndrome were evaluated on CT. The shape and distribution of intrahepatic low densities and the presence of hepatomegaly and/or splenomegaly were reviewed on CT, and the percentage of eosinophils in peripheral blood was also determined. In seven cases, interval change in hepatic lesion and the percentage of eosinophils were reviewed on follow-up examination. On initial CT, varying low-density patterns were seen in the liver in all cases; hepatomegaly was seen in four cases, and hepatosplenomegaly in two. The percentage of eosinophils was 89% in a case with diffuse patch low densities in the liver, 65-85% in three cases with numerous nodular low density lesions, 12-29% in four cases with multiple (below ten) nodular or small geographic hypodense lesions, and 24% in a case with a single nodular hypodense lesion. On follow-up CT, seven patients showed a decrease in the percentage of eosinophils, and in six, improved intrahepatic low densities were seen. On CT, intrahepatic low densities were seen in patients with idiopathic hypereosinophilic syndrome, and these were distributed more extensively when peripheral eosinophilia was more severe. With improvement in peripheral eosinophilia, the low densities also improved

Can CT and MR Shape and Textural Features Differentiate Benign Versus Malignant Pleural Lesions?

Science.gov (United States)

Pena, Elena; Ojiaku, MacArinze; Inacio, Joao R; Gupta, Ashish; Macdonald, D Blair; Shabana, Wael; Seely, Jean M; Rybicki, Frank J; Dennie, Carole; Thornhill, Rebecca E

2017-10-01

The study aimed to identify a radiomic approach based on CT and or magnetic resonance (MR) features (shape and texture) that may help differentiate benign versus malignant pleural lesions, and to assess if the radiomic model may improve confidence and accuracy of radiologists with different subspecialty backgrounds. Twenty-nine patients with pleural lesions studied on both contrast-enhanced CT and MR imaging were reviewed retrospectively. Three texture and three shape features were extracted. Combinations of features were used to generate logistic regression models using histopathology as outcome. Two thoracic and two abdominal radiologists evaluated their degree of confidence in malignancy. Diagnostic accuracy of radiologists was determined using contingency tables. Cohen's kappa coefficient was used to assess inter-reader agreement. Using optimal threshold criteria, sensitivity, specificity, and accuracy of each feature and combination of features were obtained and compared to the accuracy and confidence of radiologists. The CT model that best discriminated malignant from benign lesions revealed an AUC CT  = 0.92 ± 0.05 (P textural and shape analysis may help distinguish malignant from benign lesions. A radiomics-based approach may increase diagnostic confidence of abdominal radiologists on CT and MR and may potentially improve radiologists' accuracy in the assessment of pleural lesions characterized by MR. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Crescentic and ring-shaped opacities. CT features in two cases of bronchiolitis obliterans organizing pneumonia (BOOP)

International Nuclear Information System (INIS)

Voloudaki, A.E.; Bouros, D.E.; Froudarakis, M.E.; Datseris, G.E.; Apostolaki, E.G.; Gourtsoyiannis, N.C.

1996-01-01

Two cases of idiopathic bronchilitis obliterans organizing pneumonia (BOOP) with unusual CT findings are presented. On CT both cases exhibited crescentic and ring-shaped opacities, surrounding areas of groundglass attenuation, and associated with a nodular pattern in one patient and airspace consolidations in the second patient. CT-pathologic correlation dislosed that the central areas of groundglass attenuation corresponded to alveolar septal inflammation, in contrast to the denser periphery where granulomatous tissue in peripheral airspaces predominated. In the broad spectrum of CT findings, BOOP can exhibit specific CT features with regard to the crescentic or ring-shaped opacities with a central groundglass attenuation area. Since these features have not been described in any other disease, they might be characteristic features for the diagnosis of BOOP. (orig.)

CT features of abdominal plasma cell neoplasms

International Nuclear Information System (INIS)

Monill, J.; Pernas, J.; Montserrat, E.; Perez, C.; Clavero, J.; Martinez-Noguera, A.; Guerrero, R.; Torrubia, S.

2005-01-01

The aim of this study was to describe the CT features of abdominal plasma cell neoplasms. We reviewed CT imaging findings in 11 patients (seven men, four women; mean age 62 years) with plasma cell neoplasms and abdominal involvement. Helical CT of the entire abdomen and pelvis was performed following intravenous administration of contrast material. Images were analyzed in consensus by two radiologists. Diagnoses were made from biopsy, surgery and/or clinical follow-up findings. Multiple myeloma was found in seven patients and extramedullary plasmacytoma in four patients. All patients with multiple myeloma had multifocal disease with involvement of perirenal space (4/7), retroperitoneal and pelvic lymph nodes (3/7), peritoneum (3/7), liver (2/7), subcutaneous tissues (2/7) and kidney (1/7). In three of the four patients with extramedullary plasmacytoma, a single site was involved, namely stomach, vagina and retroperitoneum. In the fourth patient, a double site of abdominal involvement was observed with rectal and jejunal masses. Plasma cell neoplasm should be considered in the differential diagnosis of single or multiple enhancing masses in the abdomen or pelvis. Abdominal plasma cell neoplasms were most frequently seen as well-defined enhancing masses (10/11). (orig.)

Utility of bolus dynamic CT for the detection of hypervascular malignant hepatic tumors. Mainly referring to the comparison with delayed phase contrast-enhanced CT

International Nuclear Information System (INIS)

Matsuda, Hiromichi; Abe, Kimihiko; Freeny, P.C.

1996-01-01

In order to analyze the usefulness of dynamic contrast-enhanced CT, 84 patients who had hepatocellular carcinoma or suspected hypervascular metastases were studied with conventional incremental dynamic CT (CID-CT) or double helical CT (DH-CT). Delayed phase contrast-enhanced CT studies were consecutively performed in all patients. Thirty-six of 84 patients had malignant hepatic neoplasms; six had hepatocellular carcinoma and 30 had metastatic tumors. At first, the detectability of hepatic lesions was evaluated with bolus dynamic CT and delayed phase CT. Dynamic CT has detected more lesions than delayed CT. Some hepatic lesions described as isodensity were missed on CID-CT. Therefore, delayed phase CT cannot be eliminated when CID-CT is performed. Secondly, hepatic lesion detectability with CID-CT was compared with that of DH-CT. DH-CT did not miss the hepatic lesions picked up by delayed phase CT and was expected to provide excellent detectability of hypervascular hepatic neoplasms. In addition, first helical CT showed most hepatic lesions as areas of obvious hyperdensity, while CID-CT did not show their correct vascularities. So-called hypervascular hepatic tumors, however, were not always hypervascular and were demonstrated as areas of iso-hypodensity even on initial helical scanning. Second helical CT was useful to detect these so-called hypervascular, but actually hypovascular lesions. In conclusion, dynamic CT was helpful in detecting hypervascular hepatic malignant neoplasms, and DH-CT was more accurate than-CID-CT for the detection of hepatic lesions and the evaluation of vascular lesion. (author)

Tuberculous adenitis: comparison of CT and MRI findings with histopathological features

International Nuclear Information System (INIS)

Backer, A.I. de; Mortele, K.J.; Heuvel, E. van den; Vanschoubroeck, I.J.; Kockx, M.M.; Vyvere, M. van de

2007-01-01

Our aim was to investigate the relationship between the various histopathological features and the CT and MRI findings in routinely submitted histopathological specimens for the diagnosis of tuberculous lymphadenopathy. Twelve formalin-fixed, paraffin-embedded tissue blocks from ten patients who were clinically suspected of having tuberculous lymphadenopathy were evaluated. We assessed the presence of histopathological features including granuloma formation, caseous necrosis, and presence of Langhans-type giant cells, calcifications, fibrosis or normal lymphoid tissue. We performed polymerase chain reaction (PCR)-based assay for mycobacterial DNA and Ziehl-Neelsen staining for acid-fast bacilli (AFB). Findings were compared with those of CT and MRI, including signal intensities on unenhanced MR images, lymph node homogeneity, attenuation values on contrast-enhanced CT and enhancement patterns on MRI. Based on CT and MRI findings, four lymph node types could be defined: (1) homogeneous nodes, visible on both pre- and post-contrast images and corresponding histopathologically to granulation tissue without or with minimal caseation necrosis (n = 2); (2) heterogeneous nodes, showing heterogeneous enhancement patterns with central non-enhancing areas and corresponding to minor or moderate intranodal caseation/liquefaction necrosis (n = 3); (3) nodes showing peripheral rim enhancement and corresponding to moderate or extensive intranodal caseation/liquefaction necrosis (n = 5); (4) heterogeneous nodes showing intranodal hyperdensities on CT and hypointense areas on T1- and T2-weighted images and corresponding to fibrosis and calcifications (n = 2). On CT and MRI, the findings reflect different stages of the tuberculous process. Imaging findings depend on the presence and the degree of granuloma formation, caseation/liquefaction necrosis, fibrosis and calcifications. (orig.)

Background area effects on feature detectability in CT and uncorrelated noise

International Nuclear Information System (INIS)

Swensson, R.G.; Judy, P.F.

1987-01-01

Receiver operating characteristic curve measures of feature detectability decrease substantially when the surrounding area of uniform-noise background is small relative to that of the feature itself. The effect occurs with both fixed and variable-level backgrounds, but differs in form for CT and uncorrelated noise. Cross-correlation image calculations can only predict these effects by treating feature detection as the discrimination of a local change (a ''feature'') from the estimated level of an assumed-uniform region of background

Vascular anatomy of the liver and porta hepatis with dynamic CT scan

International Nuclear Information System (INIS)

Hiramatsu, Yoshihiro; Wada, Mitsuyoshi; Nakajima, Teiichi; Tonooka, Reiko; Matsumoto, Kunihiko

1983-01-01

Vascular anatomy of the liver and porta heaptis demonstrated by dynamic CT scan was studied Identification of the individual vessels was sometimes difficult due to slight differencies in respiratory depths among the scans. Limitation in the number of slices also made the evalution of the vascular anatomy difficult. Angiography was therefore utilized for comparison in identifying the vessels. Dynamic CT scan was proved to be usefull in demonstrating the anteroposterior relationship of the vessels and surrounding structures, which is difficult with convetional angiography without multiple projections. Three dimensional understanding of the vessels was then possible with dynamic CT scan and angiography. When combined with recently advancing digital subtraction angiography, dynamic CT scan might reduce the necessity for conventional angiography with Seldinger's technique. (author)

Dynamic CT for Parathyroid Adenoma Detection: How Does Radiation Dose Compare With Nuclear Medicine?

Science.gov (United States)

Czarnecki, Caroline A; Einsiedel, Paul F; Phal, Pramit M; Miller, Julie A; Lichtenstein, Meir; Stella, Damien L

2018-05-01

Dynamic CT is increasingly used for preoperative localization of parathyroid adenomas, but concerns remain about the radiation effective dose of CT compared with that of 99m Tc-sestamibi scintigraphy. The purpose of this study was to compare the radiation dose delivered by three-phase dynamic CT with that delivered by 99m Tc-sestamibi SPECT/CT performed in accordance with our current protocols and to assess the possible reduction in effective dose achieved by decreasing the scan length (i.e., z-axis) of two phases of the dynamic CT protocol. The effective dose of a 99m Tc-sestamibi nuclear medicine parathyroid study performed with and without coregistration CT was calculated and compared with the effective dose of our current three-phase dynamic CT protocol as well as a proposed protocol involving CT with reduced scan length. The median effective dose for a 99m Tc-sestamibi nuclear medicine study was 5.6 mSv. This increased to 12.4 mSv with the addition of coregistration CT, which is higher than the median effective dose of 9.3 mSv associated with the dynamic CT protocol. Reducing the scan length of two phases in the dynamic CT protocol could reduce the median effective dose to 6.1 mSv, which would be similar to that of the dose from the 99m Tc-sestamibi study alone. Dynamic CT used for the detection of parathyroid adenoma can deliver a lower radiation dose than 99m Tc-sestamibi SPECT/CT. It may be possible to reduce the dose further by decreasing the scan length of two of the phases, although whether this has an impact on accuracy of the localization needs further investigation.

Multimodality functional imaging of spontaneous canine tumors using 64CU-ATSM and 18FDG PET/CT and dynamic contrast enhanced perfusion CT

DEFF Research Database (Denmark)

Hansen, Anders E; Kristensen, Annemarie T; Law, Ian

2012-01-01

To compare the distribution and uptake of the hypoxia tracer (64)Cu-diacetyl-bis(N(4)-methylthiosemicarbazone) ((64)Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition (64)Cu-ATSM distribution over time was evaluated.......To compare the distribution and uptake of the hypoxia tracer (64)Cu-diacetyl-bis(N(4)-methylthiosemicarbazone) ((64)Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition (64)Cu-ATSM distribution over time was evaluated....

Textural features and SUV-based variables assessed by dual time point 18F-FDG PET/CT in locally advanced breast cancer.

Science.gov (United States)

Garcia-Vicente, Ana María; Molina, David; Pérez-Beteta, Julián; Amo-Salas, Mariano; Martínez-González, Alicia; Bueno, Gloria; Tello-Galán, María Jesús; Soriano-Castrejón, Ángel

2017-12-01

To study the influence of dual time point 18F-FDG PET/CT in textural features and SUV-based variables and their relation among them. Fifty-six patients with locally advanced breast cancer (LABC) were prospectively included. All of them underwent a standard 18F-FDG PET/CT (PET-1) and a delayed acquisition (PET-2). After segmentation, SUV variables (SUVmax, SUVmean, and SUVpeak), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were obtained. Eighteen three-dimensional (3D) textural measures were computed including: run-length matrices (RLM) features, co-occurrence matrices (CM) features, and energies. Differences between all PET-derived variables obtained in PET-1 and PET-2 were studied. Significant differences were found between the SUV-based parameters and MTV obtained in the dual time point PET/CT, with higher values of SUV-based variables and lower MTV in the PET-2 with respect to the PET-1. In relation with the textural parameters obtained in dual time point acquisition, significant differences were found for the short run emphasis, low gray-level run emphasis, short run high gray-level emphasis, run percentage, long run emphasis, gray-level non-uniformity, homogeneity, and dissimilarity. Textural variables showed relations with MTV and TLG. Significant differences of textural features were found in dual time point 18F-FDG PET/CT. Thus, a dynamic behavior of metabolic characteristics should be expected, with higher heterogeneity in delayed PET acquisition compared with the standard PET. A greater heterogeneity was found in bigger tumors.

CT imaging features of tuberculous spondylitis in children

International Nuclear Information System (INIS)

Song Min; Liu Wen; Fang Weijun; Wang Fukang; Li Ziping

2009-01-01

Objective: To investigate CT imaging features of tuberculous spondylitis in children. Methods: The CT imagings of two groups of patients with Tuberculous Spondylitis between January 2004 and March 2008 were retrospectively reviewed. One group included 28 children from 0 to 14 years old. Another group included 159 adults. All the patients were diagnosed as tuberculous spondylitis by pathology or biopsy, or by anti-turboelectric therapy. The CT imagings of the two groups were read retrospectively, including infections of vertebras and its appendix, the proportion of the total length of paravertebral abscess to the height of relative vertebra, the information of paravertebral abscess and dura mate of spinal cord and nerve root compression. Results The ratio of kyphosis in children group was 75% (21/28), higher than that in adults'. Tuberculous spondylitis in children was most often involved thoracic vertebra (53.7%,51/95). In children, involvement was more often seen than that of cervical vertebra and lumbar. The ratio of tuberculous spondylitis of children's cervical vertebrae was 10.5% (10/95)and of lumbar was 31.6% (30/95, while in adults that of cervical vertebrae was 3.3% (16/479)and of lumbar was 44.5% (213/479). There was statistical difference between them. The percentages of central type of tuberculous vertebral osteitis in chlidren was 57.1% (16/28)and was different with that in adults'(P=0.001 0.05). The incidence of dura mate of spinal cord or nerve root compression in children was 78.6%(22/28), much higher than that in adults (49.7%(79/159), P=0.005 <0.05). Conclusion: Special features of tuberculous spondylitis in childrencan be observed on CT imaging, kyphosis is often seen. The incidence of tuberculous spondylitis of thoracic vertebra and cervical vertebrae is high, central type of tuberculous vertebral osteitis in children is more popular than that in adults, but there is higher ratio of dura mate of spinal cord or nerve root compression in children

Development of a dynamic flow imaging phantom for dynamic contrast-enhanced CT

International Nuclear Information System (INIS)

Driscoll, B.; Keller, H.; Coolens, C.

2011-01-01

Purpose: Dynamic contrast enhanced CT (DCE-CT) studies with modeling of blood flow and tissue perfusion are becoming more prevalent in the clinic, with advances in wide volume CT scanners allowing the imaging of an entire organ with sub-second image frequency and sub-millimeter accuracy. Wide-spread implementation of perfusion DCE-CT, however, is pending fundamental validation of the quantitative parameters that result from dynamic contrast imaging and perfusion modeling. Therefore, the goal of this work was to design and construct a novel dynamic flow imaging phantom capable of producing typical clinical time-attenuation curves (TACs) with the purpose of developing a framework for the quantification and validation of DCE-CT measurements and kinetic modeling under realistic flow conditions. Methods: The phantom is based on a simple two-compartment model and was printed using a 3D printer. Initial analysis of the phantom involved simple flow measurements and progressed to DCE-CT experiments in order to test the phantoms range and reproducibility. The phantom was then utilized to generate realistic input TACs. A phantom prediction model was developed to compute the input and output TACs based on a given set of five experimental (control) parameters: pump flow rate, injection pump flow rate, injection contrast concentration, and both control valve positions. The prediction model is then inversely applied to determine the control parameters necessary to generate a set of desired input and output TACs. A protocol was developed and performed using the phantom to investigate image noise, partial volume effects and CT number accuracy under realistic flow conditionsResults: This phantom and its surrounding flow system are capable of creating a wide range of physiologically relevant TACs, which are reproducible with minimal error between experiments (σ/μ 2 ) for the input function between 0.95 and 0.98, while the maximum enhancement differed by no more than 3.3%. The

The linear attenuation coefficients as features of multiple energy CT image classification

International Nuclear Information System (INIS)

Homem, M.R.P.; Mascarenhas, N.D.A.; Cruvinel, P.E.

2000-01-01

We present in this paper an analysis of the linear attenuation coefficients as useful features of single and multiple energy CT images with the use of statistical pattern classification tools. We analyzed four CT images through two pointwise classifiers (the first classifier is based on the maximum-likelihood criterion and the second classifier is based on the k-means clustering algorithm) and one contextual Bayesian classifier (ICM algorithm - Iterated Conditional Modes) using an a priori Potts-Strauss model. A feature extraction procedure using the Jeffries-Matusita (J-M) distance and the Karhunen-Loeve transformation was also performed. Both the classification and the feature selection procedures were found to be in agreement with the predicted discrimination given by the separation of the linear attenuation coefficient curves for different materials

Analysis on CT features of tumor-like gastric schwannomas

International Nuclear Information System (INIS)

Zhang Yu; Chen Jie

2011-01-01

Objective: To analyze CT imaging features of tumor-like gastric schwannomas. Methods: Ten patients with gastric schwannomas were retrospectively analyzed. All were scanned with pre-and pro-enhanced CT. Analysis of the CT findings included evaluation of the volume, number, location, contour, growth pattern, border, enhancement pattern, and enhancement grade as well as the presence of surface dimpling, integrity of overlying mucosa. All cases were confirmed by pathology. Results: In every case, simple tumor was present. The largest was about 5.7 cm in the diameter, the smallest was 2.3 cm. All tumors were round or oval, and one tumor was slightly lobulated. Endoluminal growth pattern was defined in two cases, exoluminal growth pattern was defined in one case, and a mixed growth pattern was noted in the rest. The borders of tumors were clear. In arterial phase, no visible enhancement was present in eight cases and mild enhancement in two cases. All cases were constantly enhanced in portal phase. Superficial ulcers were present in four cases. Conclusion: CT findings of tumor-like gastric schwannomas are distinctive to a certain degree. It can be used to guide clinical therapy. (authors)

CT study of pancreatic diseases with modified dynamic scanning

International Nuclear Information System (INIS)

Qian Minghui; Zhu Guangying

1990-01-01

Experience of 20 cases modified dynamic CT scanning is presented. With a slight increased X-ray tube burden, it is possible to investigate tumor blood supply and find small pancreatic insulinoma with this method. The capsular sign typical for chronic traumatic pancreatic hematoma on CT is presented

Learning with distribution of optimized features for recognizing common CT imaging signs of lung diseases

Science.gov (United States)

Ma, Ling; Liu, Xiabi; Fei, Baowei

2017-01-01

Common CT imaging signs of lung diseases (CISLs) are defined as the imaging signs that frequently appear in lung CT images from patients. CISLs play important roles in the diagnosis of lung diseases. This paper proposes a novel learning method, namely learning with distribution of optimized feature (DOF), to effectively recognize the characteristics of CISLs. We improve the classification performance by learning the optimized features under different distributions. Specifically, we adopt the minimum spanning tree algorithm to capture the relationship between features and discriminant ability of features for selecting the most important features. To overcome the problem of various distributions in one CISL, we propose a hierarchical learning method. First, we use an unsupervised learning method to cluster samples into groups based on their distribution. Second, in each group, we use a supervised learning method to train a model based on their categories of CISLs. Finally, we obtain multiple classification decisions from multiple trained models and use majority voting to achieve the final decision. The proposed approach has been implemented on a set of 511 samples captured from human lung CT images and achieves a classification accuracy of 91.96%. The proposed DOF method is effective and can provide a useful tool for computer-aided diagnosis of lung diseases on CT images.

Feature-based US to CT registration of the aortic root

Science.gov (United States)

Lang, Pencilla; Chen, Elvis C. S.; Guiraudon, Gerard M.; Jones, Doug L.; Bainbridge, Daniel; Chu, Michael W.; Drangova, Maria; Hata, Noby; Jain, Ameet; Peters, Terry M.

2011-03-01

A feature-based registration was developed to align biplane and tracked ultrasound images of the aortic root with a preoperative CT volume. In transcatheter aortic valve replacement, a prosthetic valve is inserted into the aortic annulus via a catheter. Poor anatomical visualization of the aortic root region can result in incorrect positioning, leading to significant morbidity and mortality. Registration of pre-operative CT to transesophageal ultrasound and fluoroscopy images is a major step towards providing augmented image guidance for this procedure. The proposed registration approach uses an iterative closest point algorithm to register a surface mesh generated from CT to 3D US points reconstructed from a single biplane US acquisition, or multiple tracked US images. The use of a single simultaneous acquisition biplane image eliminates reconstruction error introduced by cardiac gating and TEE probe tracking, creating potential for real-time intra-operative registration. A simple initialization procedure is used to minimize changes to operating room workflow. The algorithm is tested on images acquired from excised porcine hearts. Results demonstrate a clinically acceptable accuracy of 2.6mm and 5mm for tracked US to CT and biplane US to CT registration respectively.

Enhanced dual-phase spiral CT features of polypoid ampullary carcinoma

International Nuclear Information System (INIS)

Zeng Mengsu; Yan Fuhua; Zhou Kangrong; Chen Huiming; Chen Gang; Chen Jin

2001-01-01

Objective: To understand CT features of polypoid ampullary carcinoma by enhanced dual-phase spiral CT. Methods: 15 cases of polypoid ampullary carcinoma (PAC) confirmed by surgical and pathological results were studied with thin slice enhanced dual-phase spiral CT (including arterial and portal phase scanning)with retrospective analysis, the scanning parameters were 5 mm thickness and 1.0 pitch for arterial phase scanning, and 5 mm thickness and 5 mm space for portal phase scanning. Results: All cases could display an enhanced mass as local filling defect at the site of the duodenal Vater's ampulla during arterial and portal phase scanning, the tumors ranged in size from 1 cm to 5 cm with mean of 2.3 cm, all were accompanied with dilated intrahepatic and common bile duct, enlarged gallbladder and dilated pancreatic duct, except one case which had marked atrophy of the pancreatic body and tail. Conclusion: The thin slices enhanced dual-phase spiral CT could not only accurately define the level of obstruction, but also demonstrate an enhanced mass as direct CT sign of the PAC, which is crucial for diagnosis of the PAC

Diagnostic value of dynamic CT in early cerebral infarct

International Nuclear Information System (INIS)

Huang, K.-M.; Shih, T.T.F.

1989-01-01

The authors have tried to demonstrate early cerebral infarct by dynamic CT scanning without any CT change. They also have tried to find a correlation between the clinical outcome and the hemodynamic change of the damaged brain tissue supplied by the occluded vessels. (author) 14 refs.; 3 figs

Hepatic sinusoidal obstruction syndrome caused by herbal medicine: CT and MRI features

International Nuclear Information System (INIS)

Zhou, Hua; Lou, Hai Yan; Wang, Yi Xiang J.; Xu, Xiao Jun; Zhang, Min Ming

2014-01-01

To describe the CT and MRI features of hepatic sinusoidal obstruction syndrome (HSOS) caused by herbal medicine Gynura segetum. The CT and MRI features of 16 consecutive Gynura segetum induced HSOS cases (12 men, 4 women) were analyzed. Eight patients had CT; three patients had MRI, and the remaining five patients had both CT and MRI examinations. Based on their clinical presentations and outcomes, the patients were classified into three categories: mild, moderate, and severe. The severity of the disease was also evaluated radiologically based on the abnormal hepatic patchy enhancement in post-contrast CT or MRI images. Ascites, patchy liver enhancement, and main right hepatic vein narrowing or occlusion were present in all 16 cases. Hepatomegaly and gallbladder wall thickening were present in 14 cases (87.5%, 14/16). Periportal high intensity on T2-weighted images was present in 6 cases (75%, 6/8). Normal liver parenchymal enhancement surrounding the main hepatic vein forming a clover-like sign was observed in 4 cases (25%, 4/16). The extent of patchy liver enhancement was statistically associated with clinical severity classification (kappa = 0.565). Ascites, patchy liver enhancement, and the main hepatic veins narrowing were the most frequent signs of herbal medicine induced HSOS. The grade of abnormal patchy liver enhancement was associated with the clinical severity.

Hepatic sinusoidal obstruction syndrome caused by herbal medicine: CT and MRI features

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Zhou, Hua; Lou, Hai Yan [Dept. of Radiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou (China); Wang, Yi Xiang J. [Dept. of Radiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou (China); Xu, Xiao Jun; Zhang, Min Ming [Dept. of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou (China)

2014-04-15

To describe the CT and MRI features of hepatic sinusoidal obstruction syndrome (HSOS) caused by herbal medicine Gynura segetum. The CT and MRI features of 16 consecutive Gynura segetum induced HSOS cases (12 men, 4 women) were analyzed. Eight patients had CT; three patients had MRI, and the remaining five patients had both CT and MRI examinations. Based on their clinical presentations and outcomes, the patients were classified into three categories: mild, moderate, and severe. The severity of the disease was also evaluated radiologically based on the abnormal hepatic patchy enhancement in post-contrast CT or MRI images. Ascites, patchy liver enhancement, and main right hepatic vein narrowing or occlusion were present in all 16 cases. Hepatomegaly and gallbladder wall thickening were present in 14 cases (87.5%, 14/16). Periportal high intensity on T2-weighted images was present in 6 cases (75%, 6/8). Normal liver parenchymal enhancement surrounding the main hepatic vein forming a clover-like sign was observed in 4 cases (25%, 4/16). The extent of patchy liver enhancement was statistically associated with clinical severity classification (kappa = 0.565). Ascites, patchy liver enhancement, and the main hepatic veins narrowing were the most frequent signs of herbal medicine induced HSOS. The grade of abnormal patchy liver enhancement was associated with the clinical severity.

Automated movement correction for dynamic PET/CT images: evaluation with phantom and patient data.

Science.gov (United States)

Ye, Hu; Wong, Koon-Pong; Wardak, Mirwais; Dahlbom, Magnus; Kepe, Vladimir; Barrio, Jorge R; Nelson, Linda D; Small, Gary W; Huang, Sung-Cheng

2014-01-01

Head movement during a dynamic brain PET/CT imaging results in mismatch between CT and dynamic PET images. It can cause artifacts in CT-based attenuation corrected PET images, thus affecting both the qualitative and quantitative aspects of the dynamic PET images and the derived parametric images. In this study, we developed an automated retrospective image-based movement correction (MC) procedure. The MC method first registered the CT image to each dynamic PET frames, then re-reconstructed the PET frames with CT-based attenuation correction, and finally re-aligned all the PET frames to the same position. We evaluated the MC method's performance on the Hoffman phantom and dynamic FDDNP and FDG PET/CT images of patients with neurodegenerative disease or with poor compliance. Dynamic FDDNP PET/CT images (65 min) were obtained from 12 patients and dynamic FDG PET/CT images (60 min) were obtained from 6 patients. Logan analysis with cerebellum as the reference region was used to generate regional distribution volume ratio (DVR) for FDDNP scan before and after MC. For FDG studies, the image derived input function was used to generate parametric image of FDG uptake constant (Ki) before and after MC. Phantom study showed high accuracy of registration between PET and CT and improved PET images after MC. In patient study, head movement was observed in all subjects, especially in late PET frames with an average displacement of 6.92 mm. The z-direction translation (average maximum = 5.32 mm) and x-axis rotation (average maximum = 5.19 degrees) occurred most frequently. Image artifacts were significantly diminished after MC. There were significant differences (Pdynamic brain FDDNP and FDG PET/CT scans could improve the qualitative and quantitative aspects of images of both tracers.

Prognostic Value and Reproducibility of Pretreatment CT Texture Features in Stage III Non-Small Cell Lung Cancer

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Fried, David V. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States); Tucker, Susan L. [Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zhou, Shouhao [Division of Quantitative Sciences, Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Liao, Zhongxing [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mawlawi, Osama [Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States); Ibbott, Geoffrey [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States); Court, Laurence E., E-mail: LECourt@mdanderson.org [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States)

2014-11-15

Purpose: To determine whether pretreatment CT texture features can improve patient risk stratification beyond conventional prognostic factors (CPFs) in stage III non-small cell lung cancer (NSCLC). Methods and Materials: We retrospectively reviewed 91 cases with stage III NSCLC treated with definitive chemoradiation therapy. All patients underwent pretreatment diagnostic contrast enhanced computed tomography (CE-CT) followed by 4-dimensional CT (4D-CT) for treatment simulation. We used the average-CT and expiratory (T50-CT) images from the 4D-CT along with the CE-CT for texture extraction. Histogram, gradient, co-occurrence, gray tone difference, and filtration-based techniques were used for texture feature extraction. Penalized Cox regression implementing cross-validation was used for covariate selection and modeling. Models incorporating texture features from the 33 image types and CPFs were compared to those with models incorporating CPFs alone for overall survival (OS), local-regional control (LRC), and freedom from distant metastases (FFDM). Predictive Kaplan-Meier curves were generated using leave-one-out cross-validation. Patients were stratified based on whether their predicted outcome was above or below the median. Reproducibility of texture features was evaluated using test-retest scans from independent patients and quantified using concordance correlation coefficients (CCC). We compared models incorporating the reproducibility seen on test-retest scans to our original models and determined the classification reproducibility. Results: Models incorporating both texture features and CPFs demonstrated a significant improvement in risk stratification compared to models using CPFs alone for OS (P=.046), LRC (P=.01), and FFDM (P=.005). The average CCCs were 0.89, 0.91, and 0.67 for texture features extracted from the average-CT, T50-CT, and CE-CT, respectively. Incorporating reproducibility within our models yielded 80.4% (±3.7% SD), 78.3% (±4.0% SD), and 78

Prognostic Value and Reproducibility of Pretreatment CT Texture Features in Stage III Non-Small Cell Lung Cancer

International Nuclear Information System (INIS)

Fried, David V.; Tucker, Susan L.; Zhou, Shouhao; Liao, Zhongxing; Mawlawi, Osama; Ibbott, Geoffrey; Court, Laurence E.

2014-01-01

Purpose: To determine whether pretreatment CT texture features can improve patient risk stratification beyond conventional prognostic factors (CPFs) in stage III non-small cell lung cancer (NSCLC). Methods and Materials: We retrospectively reviewed 91 cases with stage III NSCLC treated with definitive chemoradiation therapy. All patients underwent pretreatment diagnostic contrast enhanced computed tomography (CE-CT) followed by 4-dimensional CT (4D-CT) for treatment simulation. We used the average-CT and expiratory (T50-CT) images from the 4D-CT along with the CE-CT for texture extraction. Histogram, gradient, co-occurrence, gray tone difference, and filtration-based techniques were used for texture feature extraction. Penalized Cox regression implementing cross-validation was used for covariate selection and modeling. Models incorporating texture features from the 33 image types and CPFs were compared to those with models incorporating CPFs alone for overall survival (OS), local-regional control (LRC), and freedom from distant metastases (FFDM). Predictive Kaplan-Meier curves were generated using leave-one-out cross-validation. Patients were stratified based on whether their predicted outcome was above or below the median. Reproducibility of texture features was evaluated using test-retest scans from independent patients and quantified using concordance correlation coefficients (CCC). We compared models incorporating the reproducibility seen on test-retest scans to our original models and determined the classification reproducibility. Results: Models incorporating both texture features and CPFs demonstrated a significant improvement in risk stratification compared to models using CPFs alone for OS (P=.046), LRC (P=.01), and FFDM (P=.005). The average CCCs were 0.89, 0.91, and 0.67 for texture features extracted from the average-CT, T50-CT, and CE-CT, respectively. Incorporating reproducibility within our models yielded 80.4% (±3.7% SD), 78.3% (±4.0% SD), and 78

Spiral CT features and anatomic basis of posterior pararenal space involvement in acute pancreatitis

International Nuclear Information System (INIS)

Min Pengqiu; Yan Zhihan; Yang Hengxuan; Liu Zaiyi; Song Bin; Wu Bing; Zhang Jin; Liu Rongbo

2005-01-01

Objective: To evaluate spiral CT features and anatomic basis of the posterior pararenal space (PPS) involvement in acute pancreatitis (AP). Methods: CT images of 87 cases with AP were retrospectively studied with focus on spiral CT features, incidence of the PPS involvement, and its correlations with the posterior renal fascia or lateroconal fascia. Results: Our study showed that the incidence of the PPS involvement was 47% (41/87), with Grade A 53% (46/87), Grade B 24%(21/87), and Grade C 23% (20/87), and Grade 0 53% (46/87), Grade I 22% (19/87), and Grade II 25% (22/87), respectively. The pancreatitis fluid collection in the PPS was continuous with that in the anterior pararenal space or with the fluid between the two laminae of the posterior renal fascia. In 3 follow-up cases, pseudocysts in the PPS were continuous with that in anterior pararenal space below the cone of renal fascia. Conclusion: Spiral CT features of the PPS involvement varies from mild inflammatory changes to fluid collection or phlegmonous mass. Fluid within anterior pararenal space in AP flows into the PPS by three routes. (authors)

Improved dynamic CT angiography visualization by flow territory masking

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Søren Christensen

2015-01-01

Full Text Available Backgound and Purpose: Computerized tomography (CT perfusion (or CTP source images from CT scanners with small detector widths can be used to create a dynamic CT angiogram (CTA similar to digital subtraction angiography (DSA. Because CTP studies use a single intravenous injection, all arterial territories enhance simultaneously, and individual arterial territories [i.e., anterior cerebral artery (ACA, middle cerebral artery (MCA, and posterior cerebral artery (PCA] cannot be delineated. This limits the ability to assess collateral flow patterns on dynamic CTAs. The aim of this study was to devise and test a postprocessing method to selectively color-label the major arterial territories on dynamic CTA. Materials and Methods: We identified 22 acute-stroke patients who underwent CTP on a 320-slice CT scanner within 6 h from symptom onset. For each case, two investigators independently generated an arterial territory map from CTP bolus arrival maps using a semiautomated method. The volumes of the arterial territories were calculated for each map and the average relative difference between these volumes was calculated for each case as a measure of interrater agreement. Arterial territory maps were superimposed on the dynamic CTA to create a vessel-selective dynamic CTA with color-coding of the main arterial territories. Two experts rated the arterial territory maps and the color-coded CTAs for consistency with expected arterial territories on a 3-point scale (excellent, moderate, poor. Results: Arterial territory maps were generated for all 22 patients. The median difference in arterial territory volumes between investigators was 2.2% [interquartile range (IQR 0.6-8.5%]. Based on expert review, the arterial territory maps and the vessel-selective dynamic CTAs showed excellent consistency with the expected arterial territories in 18 of 22 patients, moderate consistency in 2 patients, and poor consistency in another 2 patients. Conclusion: Using a

CT texture features of liver parenchyma for predicting development of metastatic disease and overall survival in patients with colorectal cancer.

Science.gov (United States)

Lee, Scott J; Zea, Ryan; Kim, David H; Lubner, Meghan G; Deming, Dustin A; Pickhardt, Perry J

2018-04-01

To determine if identifiable hepatic textural features are present at abdominal CT in patients with colorectal cancer (CRC) prior to the development of CT-detectable hepatic metastases. Four filtration-histogram texture features (standard deviation, skewness, entropy and kurtosis) were extracted from the liver parenchyma on portal venous phase CT images at staging and post-treatment surveillance. Surveillance scans corresponded to the last scan prior to the development of CT-detectable CRC liver metastases in 29 patients (median time interval, 6 months), and these were compared with interval-matched surveillance scans in 60 CRC patients who did not develop liver metastases. Predictive models of liver metastasis-free survival and overall survival were built using regularised Cox proportional hazards regression. Texture features did not significantly differ between cases and controls. For Cox models using all features as predictors, all coefficients were shrunk to zero, suggesting no association between any CT texture features and outcomes. Prognostic indices derived from entropy features at surveillance CT incorrectly classified patients into risk groups for future liver metastases (p < 0.001). On surveillance CT scans immediately prior to the development of CRC liver metastases, we found no evidence suggesting that changes in identifiable hepatic texture features were predictive of their development. • No correlation between liver texture features and metastasis-free survival was observed. • Liver texture features incorrectly classified patients into risk groups for liver metastases. • Standardised texture analysis workflows need to be developed to improve research reproducibility.

Imaging features of primary Sarcomas of the great vessels in CT, MRI and PET/CT: a single-center experience

International Nuclear Information System (INIS)

Falck, Christian von; Meyer, Bernhard; Fegbeutel, Christine; Länger, Florian; Bengel, Frank; Wacker, Frank; Rodt, Thomas

2013-01-01

To investigate the imaging features of primary sarcomas of the great vessels in CT, MRI and 18 F-FDG PET/CT. Thirteen patients with a primary sarcoma of the great vessels were retrospectively evaluated. All available images studies including F-18 FDG PET(/CT) (n = 4), MDCT (n = 12) and MRI (n = 6) were evaluated and indicative image features of this rare tumor entity were identified. The median interval between the first imaging study and the final diagnosis was 11 weeks (0–12 weeks). The most frequently observed imaging findings suggestive of malignant disease in patients with sarcomas of the pulmonary arteries were a large filling defect with vascular distension, unilaterality and a lack of improvement despite effective anticoagulation. In patients with aortic sarcomas we most frequently observed a pedunculated appearance and an atypical location of the filling defect. The F-18 FDG PET(/CT) examinations demonstrated an unequivocal hypermetabolism of the lesion in all cases (4/4). MRI proved lesion vascularization in 5/6 cases. Intravascular unilateral or atypically located filling defects of the great vessels with vascular distension, a pedunculated shape and lack of improvement despite effective anticoagulation are suspicious for primary sarcoma on MDCT or MRI. MR perfusion techniques can add information on the nature of the lesion but the findings may be subtle and equivocal. F-18 FDG PET/CT may have a potential role in these patients and may be considered as part of the imaging workup

Predicting IDH mutation status of intrahepatic cholangiocarcinomas based on contrast-enhanced CT features

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Zhu, Yong [Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Department of Radiology, Nanjing, Jiangsu Province (China); Chen, Jun [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Pathology, Nanjing, Jiangsu Province (China); Kong, Weiwei [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Oncology, Nanjing, Jiangsu Province (China); Mao, Liang; Qiu, Yudong [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Hepatopancreatobiliary Surgery, Nanjing, Jiangsu Province (China); Kong, Wentao [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Ultrasonography, Nanjing, Jiangsu Province (China); Zhou, Qun [Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Department of Radiology, Nanjing, Jiangsu Province (China); Zhou, Zhengyang; Zhu, Bin; He, Jian [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Radiology, Nanjing, Jiangsu Province (China); Wang, Zhongqiu [Jiangsu Province Hospital of Traditional Chinese Medicine, the Affiliated Hospital of Nanjing University of Chinese Medicine, Department of Radiology, Nanjing, Jiangsu Province (China)

2018-01-15

To explore the difference in contrast-enhanced computed tomography (CT) features of intrahepatic cholangiocarcinomas (ICCs) with different isocitrate dehydrogenase (IDH) mutation status. Clinicopathological and contrast-enhanced CT features of 78 patients with 78 ICCs were retrospectively analysed and compared based on IDH mutation status. There were 11 ICCs with IDH mutation (11/78, 14.1%) and 67 ICCs without IDH mutation (67/78, 85.9%). IDH-mutated ICCs showed intratumoral artery more often than IDH-wild ICCs (p = 0.023). Most ICCs with IDH mutation showed rim and internal enhancement (10/11, 90.9%), while ICCs without IDH mutation often appeared diffuse (26/67, 38.8%) or with no enhancement (4/67, 6.0%) in the arterial phase (p = 0.009). IDH-mutated ICCs showed significantly higher CT values, enhancement degrees and enhancement ratios in arterial and portal venous phases than IDH-wild ICCs (all p < 0.05). The CT value of tumours in the portal venous phase performed best in distinguishing ICCs with and without IDH mutation, with an area under the curve of 0.798 (p = 0.002). ICCs with and without IDH mutation differed significantly in arterial enhancement mode, and the tumour enhancement degree on multiphase contrast-enhanced CT was helpful in predicting IDH mutation status. (orig.)

Influenza A H1N1 pneumonia: radiograph and CT features of children

International Nuclear Information System (INIS)

Cheng Hua; Duan Xiaomin; Peng Yun; Zeng Jinjin; Sun Guoqiang

2010-01-01

Objective: To explore the imaging features on chest radiograph and CT in children with Influenza A H1N1 pneumonia. Methods: The imaging data of chest radiograph and CT in six children with Influenza A H1N1 pneumonia confirmed by real-time RT-PCR assay was retrospectively analysis. All patients had chest radiograph at first examination and 4 of them re-examed. One children took CT. Results: All cases showed thick lung markings with varied degrees of pulmonary infiltration and interstitial changes on chest radiograph. Among them, 3 cases showed bilateral pulmonary infiltration and 3 cases showed infiltration in left lung; enlarged hilar was observed in 3 cases. The imaging findings of the pneumonia changed quickly during the follow-up accompanied with the improvement of clinical symptoms. The only one chest CT examination showed bilateral infiltration, multiple ground-glass opacities, small subpleural nodulars, right pleural effusion and lymphadenopathy of lung hila and mediastinum. Conclusions: Chest radiograph and CT revealed certain typical imaging features in the children with influenza A H1N1 pneumonia. However, the final diagnosis of influenza A H1N1 pneumonia still should be made based on epidemiology and laboratory examination. (authors)

Classifying features in CT imagery: accuracy for some single- and multiple-species classifiers

Science.gov (United States)

Daniel L. Schmoldt; Jing He; A. Lynn Abbott

1998-01-01

Our current approach to automatically label features in CT images of hardwood logs classifies each pixel of an image individually. These feature classifiers use a back-propagation artificial neural network (ANN) and feature vectors that include a small, local neighborhood of pixels and the distance of the target pixel to the center of the log. Initially, this type of...

Analysis of the manifestation and feature of adrenal tumor on CT in 30 cases

International Nuclear Information System (INIS)

Xi Riquan; Xie Daohai; Guo Liang; Hu Chunhong; Fu Yingdi

2001-01-01

Objective: To analyze the manifestation and the feature of adrenal tumor with CT. Methods: The findings of various adrenal tumors with CT in 30 cases were analyzed retrospectively, the key to the diagnosis and differential diagnosis was suggested. Results: Usually, fibroxanthoma is inhomogeneous in density and moderate in size and was enhanced slightly after contrast medium administration. Pheochromocytoma is always larger and inhomogeneous in density and was enhanced markedly. The CT unit of myelo-lipoma simulated those of fluid or fat. Adrenal cyst has a low CT value and it showed cystic wall calcification. Aldosteronism adenoma was low in density and small in size, while cortisol adenoma was moderate in density and medium in size. Adrenocortical adenocarcinoma was the larger one with irregular margin and irregular hypodense areas inside. Metastatic carcinoma was larger and inhomogeneous in density. Conclusion: It is possible to increase the diagnostic rate by analysing the imaging feature of adrenal tumor

Quantitative myocardial perfusion from static cardiac and dynamic arterial CT

Science.gov (United States)

Bindschadler, Michael; Branch, Kelley R.; Alessio, Adam M.

2018-05-01

Quantitative myocardial blood flow (MBF) estimation by dynamic contrast enhanced cardiac computed tomography (CT) requires multi-frame acquisition of contrast transit through the blood pool and myocardium to inform the arterial input and tissue response functions. Both the input and the tissue response functions for the entire myocardium are sampled with each acquisition. However, the long breath holds and frequent sampling can result in significant motion artifacts and relatively high radiation dose. To address these limitations, we propose and evaluate a new static cardiac and dynamic arterial (SCDA) quantitative MBF approach where (1) the input function is well sampled using either prediction from pre-scan timing bolus data or measured from dynamic thin slice ‘bolus tracking’ acquisitions, and (2) the whole-heart tissue response data is limited to one contrast enhanced CT acquisition. A perfusion model uses the dynamic arterial input function to generate a family of possible myocardial contrast enhancement curves corresponding to a range of MBF values. Combined with the timing of the single whole-heart acquisition, these curves generate a lookup table relating myocardial contrast enhancement to quantitative MBF. We tested the SCDA approach in 28 patients that underwent a full dynamic CT protocol both at rest and vasodilator stress conditions. Using measured input function plus single (enhanced CT only) or plus double (enhanced and contrast free baseline CT’s) myocardial acquisitions yielded MBF estimates with root mean square (RMS) error of 1.2 ml/min/g and 0.35 ml/min/g, and radiation dose reductions of 90% and 83%, respectively. The prediction of the input function based on timing bolus data and the static acquisition had an RMS error compared to the measured input function of 26.0% which led to MBF estimation errors greater than threefold higher than using the measured input function. SCDA presents a new, simplified approach for quantitative

Dynamic contrast-enhanced MR imaging in osteoid osteoma: relationships with clinical and CT characteristics

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Pottecher, P. [Hopital Lariboisiere, AP-HP, Department of Osteoarticular Radiology, Paris (France); Hopital du Bocage, Department of Vascular, Oncologic and Interventional Radiology, Dijon (France); Sibileau, E.; Hamze, B.; Parlier, C.; Laredo, J.D.; Bousson, V. [Hopital Lariboisiere, AP-HP, Department of Osteoarticular Radiology, Paris (France); Aho, S. [Hopital du Bocage, Hospital Hygiene and Epidemiology unit, Dijon (France)

2017-07-15

To correlate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) features to clinical and computed tomography (CT) morphological features of osteoid osteoma (OO). Our institutional review board approved this retrospective study, waiving the need for informed consent. We included the 102 patients treated with interstitial laser ablation for histologically documented OO at our institution in 2008-2013. DCE-MRI variables were the time-enhancement pattern and rising slope (Slope{sub rise}) and CT variables were the bone and segment involved (OO{sub bone} and OO{sub segment,} respectively), OO location relative to the native cortex (OO{sub cortex}), nidus surface area, vessel sign, and largest neighboring-vessel diameter (Dmax{sub vessel}). Descriptive statistics and correlations linking DCE-MRI findings to clinical and CT characteristics were computed. DCE-MRI showed early arterial peak enhancement in 95 (93%) cases, with a mean Slope{sub rise} of 9.30 ± 8.10. CT visualized a vessel sign in 84 (82%) cases with a mean Dmax{sub vessel} of 1.10 ± 0.60 mm. By univariate analysis, Slope{sub rise} correlated significantly with pain duration and Dmax{sub vessel} (r = 0.30, P = 0.003; and r = 0.22, P = 0.03; respectively). Analysis of variance showed that Slope{sub rise} correlated significantly with OO{sub bone} (P < 0.001), with a steeper slope for OOs located in short or flat bones. This study suggests more abundant vascularization of OOs with long-lasting pain and location on short or flat bones. (orig.)

MRI features of myositis ossificans with X-ray and CT findings

International Nuclear Information System (INIS)

Gu Xiang; Bai Rongjie; Qu Hui; Cheng Xiaoguang; Li Yuang

2009-01-01

Objective: To investigate the MRI features of myositis ossificans, and to address the correlation with X-ray radiography and CT findings. Methods: X-ray films, CT and MRI of 36 documented cases of myositis ossificans were retrospectively analyzed, and the literatures were reviewed. Results: Of the 36 cases, 4 cases occurred in the elbow joint, 4 in the shoulder joint, 15 in the hip joint, 6 in the tibiofibula, 5 in the femur, 1 in the metatarsal bones, and 1 in the ilium, respectively. Irregular patchy or lamellar high density calcification or ossification could be seen in the soft tissue parenchym on X-ray films and CT scan. Cortical bone integrity was preserved in diaphysis. CT enhanced scan showed that the swollen parenchyma was not enhanced and there was no parenchyma mass. On the early and middle stages, MR T 1 WI and T 2 WI showed slice-shaped low signal in the peripheral parenchyma, but patchy high signal was found around the low signal on T 2 WI. STIR showed mixed high and low signals in the swollen parenchyma with unclear demarcation. The lesions showed low signal on MR T 1 WI and T 2 WI in the late stage, and there was no edema in peripheral parenehyma. MRI enhanced scan found that the swollen parenchyma showed no enhancement in all stages. Conclusions: The imaging features of myositis ossificans have some characteristics. Misdiagnosis could be avoided when the disease was evaluated with the course. (authors)

Cardiac MR imaging: Comparison with echocardiography and dynamic CT

International Nuclear Information System (INIS)

Colletti, P.M.; Norris, S.; Raval, J.; Boswell, W.; Lee, K.; Ralls, P.; Haywood, J.; Halls, J.

1986-01-01

The authors compared gated cardiac MR imaging with two-dimensional and Doppler echocardiography and dynamic CT. Gated cardiac MR imaging (VISTA unit, 0.5 T) was performed in 55 patients with a variety of conditions. Accuracy of diagnosis was compared. CT showed arterial, valvular, and pericardial calcifications not seen on MR imaging. Many lesions were seen as well on CT as on MR imaging. Two-dimensional echocardiography was superior in demonstrating wall motion and valvular disease. MR imaging was superior in demonstrating myocardial structures

Chest CT features of cystic fibrosis in Korea: Comparison with non-cystic fibrosis diseases

International Nuclear Information System (INIS)

Yang, So Yeon; Lee, Kyung Soo; Kim, Tae Jung; Kim, Tae Sung; Cha, Min Jae; Yoon, Hyun Jung

2017-01-01

Cystic fibrosis (CF) is a rare congenital disease in Korea, and its clinical and imaging findings are unclear. The objective of our study was to describe the clinical and CT features of CF in Korea and compare its features with those of other diseases mimicking CF. From November 1994 to December 2014, a presumptive diagnosis of CF was made in 23 patients based on clinical or radiological examination. After the exclusion of 10 patients without diagnostic confirmation, 13 patients were included in the study. A diagnosis of CF was made with the CF gene study. CT findings were evaluated for the presence and distribution of parenchymal abnormalities including bronchiectasis, tree-in-bud (TIB) pattern, mucus plugging, consolidation, and mosaic attenuation. Of the 13 patients, 7 (median age, 15 years) were confirmed as CF, 4 (median age, 19 years) had primary ciliary dyskinesia, 1 had bronchiectasis of unknown cause, and 1 had chronic asthma. CT of patients with CF showed bilateral bronchiectasis, TIB pattern, mosaic attenuation, and mucus plugging in all patients, with upper lung predominance (57%). In CT of the non-CF patients, bilateral bronchiectasis, TIB pattern, mosaic attenuation, and mucus plugging were also predominant features, with lower lung predominance (50%). Korean patients with CF showed bilateral bronchiectasis, cellular bronchiolitis, mucus plugging, and mosaic attenuation, which overlapped with those of non-CF patients. CF gene study is recommended for the definitive diagnosis of CF in patients with these clinical and imaging features

Chest CT features of cystic fibrosis in Korea: Comparison with non-cystic fibrosis diseases

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Yang, So Yeon; Lee, Kyung Soo; Kim, Tae Jung; Kim, Tae Sung [Dept. of Radiology, and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Cha, Min Jae [Dept. of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul (Korea, Republic of); Yoon, Hyun Jung [Dept. of Radiology, Hanyang University Hospital, Hanyang University College of Medicine, Seoul (Korea, Republic of)

2017-01-15

Cystic fibrosis (CF) is a rare congenital disease in Korea, and its clinical and imaging findings are unclear. The objective of our study was to describe the clinical and CT features of CF in Korea and compare its features with those of other diseases mimicking CF. From November 1994 to December 2014, a presumptive diagnosis of CF was made in 23 patients based on clinical or radiological examination. After the exclusion of 10 patients without diagnostic confirmation, 13 patients were included in the study. A diagnosis of CF was made with the CF gene study. CT findings were evaluated for the presence and distribution of parenchymal abnormalities including bronchiectasis, tree-in-bud (TIB) pattern, mucus plugging, consolidation, and mosaic attenuation. Of the 13 patients, 7 (median age, 15 years) were confirmed as CF, 4 (median age, 19 years) had primary ciliary dyskinesia, 1 had bronchiectasis of unknown cause, and 1 had chronic asthma. CT of patients with CF showed bilateral bronchiectasis, TIB pattern, mosaic attenuation, and mucus plugging in all patients, with upper lung predominance (57%). In CT of the non-CF patients, bilateral bronchiectasis, TIB pattern, mosaic attenuation, and mucus plugging were also predominant features, with lower lung predominance (50%). Korean patients with CF showed bilateral bronchiectasis, cellular bronchiolitis, mucus plugging, and mosaic attenuation, which overlapped with those of non-CF patients. CF gene study is recommended for the definitive diagnosis of CF in patients with these clinical and imaging features.

CT and MR features of xanthogranulomatous cholecystitis: An analysis of consecutive 49 cases

International Nuclear Information System (INIS)

Zhao, Feng; Lu, Pu-Xuan; Yan, Sen-Xiang; Wang, Gao-Feng; Yuan, Jing; Zhang, Shi-Zheng; Wang, Yi-Xiang J.

2013-01-01

Objective: To study the CT and MR features of xanthogranulomatous cholecystitis (XGC). Materials and methods: 49 patients had pathologically confirmed XGC. All patients underwent contrast enhanced CT, and 10 patients had additional plain MRI. The CT and MRI results were retrospectively analyzed. Results: On CT, all patients had thickening of gallbladder wall, with 87.8% cases showed diffuse thickening. 85.7% cases had intramural hypo-attenuated nodules in the thickened wall. Continuous mucosal line and luminal surface enhancement were noted in 79.6% and 85.7% cases, respectively. Gallbladder stones were seen in 69.4% patients. The coexistence of the above 5 CT features was seen in 40% cases, and 80% cases had the coexistence of ≥4 features. Diffused gallbladder wall thickening in XGC is more likely to have disrupted mucosal line, and XGC with disrupted mucosal line is more likely to be associated with liver infiltration. In 60% patients the inflammatory process extended beyond gallbladder, with the interface between gallbladder and liver and/or the surrounding fat blurred. 40% cases had an early enhancement of liver parenchyma. Infiltration to other surrounding tissues included bowel (n = 3), stomach (n = 2), and abdominal wall (n = 1). On MR images, 7 of 9 intramural nodules in 7 subjects with T1-weighted dual echo MR images showed higher signal intensity on in-phase images than out-of-phase images. Conclusion: Coexisting of diffuse gallbladder wall thickening, hypo-attenuated intramural nodules, continuous mucosal line, luminal surface enhancement, and gallbladder stone highly suggest XGC. XGC frequently infiltrate liver and surrounding fat. Chemical-shift MRI helps classifying intramural nodules in the gallbladder wall

CT and MR features of xanthogranulomatous cholecystitis: An analysis of consecutive 49 cases

Energy Technology Data Exchange (ETDEWEB)

Zhao, Feng [Department of Radiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016 (China); Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong (China); Lu, Pu-Xuan [Department of Radiology, Shenzhen Third People' s Hospital, Guangdong Medical College, Shenzhen 518020 (China); Yan, Sen-Xiang [Department of Radiation Oncology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003 (China); Wang, Gao-Feng [Department of Radiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016 (China); Yuan, Jing [Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong (China); Zhang, Shi-Zheng, E-mail: shizhengzhang@hotmail.com [Department of Radiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou 310016 (China); Wang, Yi-Xiang J., E-mail: yixiang_wang@cuhk.edu.hk [Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong (China); Department of Radiology, Shenzhen Third People' s Hospital, Guangdong Medical College, Shenzhen 518020 (China)

2013-09-15

Objective: To study the CT and MR features of xanthogranulomatous cholecystitis (XGC). Materials and methods: 49 patients had pathologically confirmed XGC. All patients underwent contrast enhanced CT, and 10 patients had additional plain MRI. The CT and MRI results were retrospectively analyzed. Results: On CT, all patients had thickening of gallbladder wall, with 87.8% cases showed diffuse thickening. 85.7% cases had intramural hypo-attenuated nodules in the thickened wall. Continuous mucosal line and luminal surface enhancement were noted in 79.6% and 85.7% cases, respectively. Gallbladder stones were seen in 69.4% patients. The coexistence of the above 5 CT features was seen in 40% cases, and 80% cases had the coexistence of ≥4 features. Diffused gallbladder wall thickening in XGC is more likely to have disrupted mucosal line, and XGC with disrupted mucosal line is more likely to be associated with liver infiltration. In 60% patients the inflammatory process extended beyond gallbladder, with the interface between gallbladder and liver and/or the surrounding fat blurred. 40% cases had an early enhancement of liver parenchyma. Infiltration to other surrounding tissues included bowel (n = 3), stomach (n = 2), and abdominal wall (n = 1). On MR images, 7 of 9 intramural nodules in 7 subjects with T1-weighted dual echo MR images showed higher signal intensity on in-phase images than out-of-phase images. Conclusion: Coexisting of diffuse gallbladder wall thickening, hypo-attenuated intramural nodules, continuous mucosal line, luminal surface enhancement, and gallbladder stone highly suggest XGC. XGC frequently infiltrate liver and surrounding fat. Chemical-shift MRI helps classifying intramural nodules in the gallbladder wall.

CT features of the subtypes of thymic epithelial tumors on the basis of the world health organization classification

International Nuclear Information System (INIS)

Guo Xiaoyu; Yu Hong; Xiao Xiangsheng

2013-01-01

Thymic epithelial tumors including thymomas and thymic carcinomas have well-known heterogeneous oncologic behaviors and variable histologic features. They show variable and unpredictable evolutions ranging from an indolent non-invasive feature to a highly infiltrative and metastasising one. Currently, CT is a common and efficient imaging method for assessing thymic epithelial tumors. CT evaluation is the main reference for preoperative clinic staging and histological classification. CT features of subtypes of thymic epithelial tumors on the basis of the World Health Organization classification provide the foundation for the diagnosis and predicting prognosis. (authors)

A study on CT features of intrahepatic bile duct abscess

International Nuclear Information System (INIS)

Min Pengqiu; Li Peng; He Zhiyan; Chen Weixia; Liu Yan

2001-01-01

Objective: To evaluate CT features of intrahepatic bile duct abscess (IBDA) and its pathologic basis. Methods: The CT imaging data of 31 consecutive cases of intrahepatic bile duct abscess proved by surgery or clinical treatments from October 1989 to February 1999 were retrospectively studied. The causes included acute obstructive suppurative cholangitis and retrograde infection due to different etiologies. For all the cases, the CT manifestations of liver abscess, bile duct abnormalities, and their relationship were observed respectively. Results: Manifestations of liver abscess were revealed in all cases (31/31, 100%). The CT manifestations of bile duct abnormalities included signs of etiologies caused bile duct obstruction and other signs including cholangiectasis (29/31, 93.5%), the dilated bile ducts communicated with (5/31, 16.1%) or abut on (8/31, 25.8%) the abscesses, and gas collection in bile ducts (10/31, 32.2%). The signs showing the relationship between liver abscess and bile duct abnormalities were that the abscesses complied with the obstructive site and the dilated bile ducts (15/31, 48.4%), and the liver abscesses located in different (7/31, 22.6%) or same (4/31, 12.9%) liver lobes or segments with gas collection in the dilated bile ducts. Conclusion: The CT manifestations of IBDA included signs of liver abscess, abnormalities of bile ducts, and signs showing their relationship. CT scanning was helpful in making comprehensive and accurate diagnosis of IBDA

CT features of peritonitis associated with continuous ambulatory peritoneal dialysis

Energy Technology Data Exchange (ETDEWEB)

Yun, Ji Young; Byun, Jae Young; Lee, Sang Hoon; Kwon, Tae Ahn; Kim, Yeon Kil; Kim, Young Ok; Song, Kyung Sup [The Catholic Univ. of Korea College of Medicine, Seoul (Korea, Republic of)

1999-01-01

To evaluate the CT findings of peritonitis associated with continuous ambulatory peritoneal dialysis(CAPD). We retrospectively analyzed CT scans of 14 symptomatic patients with peritonitis after CAPD. Diffuse abdominal pain was present in 11, fever in two, and abdominal mass with vomiting in one. The mean duration of CAPD ranged from 10 months to 5 years(mean : 3.9 years). On abdominal CT, we evaluated the presence and location of ascites, bowel wall thickening, cocoon formation, the pattern of enhancement of peritoneal thickening, the presence of calcifications in the peritoneum, and mesenteric and omental change. On enhanced CT, multiloculated ascites was observed in all cases(n=14) ; it was located mainly in the pelvic cavity with small multi-loculated fluid collections in the peritoneal cavity(n=13), including the lesser sac(n=3). In one patient, ascites was located in the space between the greater omentum and anterior peritoneal surface. CT showed ileus in 12 cases, small bowel wall thickening in 11, and cocoon formation in five. Uneven but smooth thickening of the peritoneum, with contrast enhancement, was seen in eight cases, and in five of these, peritoneal thickening was more prominent in the anterior peritoneum. Other findings included reticular opacity in two cases, hematoma of the rectus muscle in one, and umbilical hernia in one. Multiloculated fluid collection, ileus, small bowel wall thickening, uneven but smooth peritoneal thickening, and cocoon formation appear to be CT features of CAPD peritonitis.

CT features of peritonitis associated with continuous ambulatory peritoneal dialysis

International Nuclear Information System (INIS)

Yun, Ji Young; Byun, Jae Young; Lee, Sang Hoon; Kwon, Tae Ahn; Kim, Yeon Kil; Kim, Young Ok; Song, Kyung Sup

1999-01-01

To evaluate the CT findings of peritonitis associated with continuous ambulatory peritoneal dialysis(CAPD). We retrospectively analyzed CT scans of 14 symptomatic patients with peritonitis after CAPD. Diffuse abdominal pain was present in 11, fever in two, and abdominal mass with vomiting in one. The mean duration of CAPD ranged from 10 months to 5 years(mean : 3.9 years). On abdominal CT, we evaluated the presence and location of ascites, bowel wall thickening, cocoon formation, the pattern of enhancement of peritoneal thickening, the presence of calcifications in the peritoneum, and mesenteric and omental change. On enhanced CT, multiloculated ascites was observed in all cases(n=14) ; it was located mainly in the pelvic cavity with small multi-loculated fluid collections in the peritoneal cavity(n=13), including the lesser sac(n=3). In one patient, ascites was located in the space between the greater omentum and anterior peritoneal surface. CT showed ileus in 12 cases, small bowel wall thickening in 11, and cocoon formation in five. Uneven but smooth thickening of the peritoneum, with contrast enhancement, was seen in eight cases, and in five of these, peritoneal thickening was more prominent in the anterior peritoneum. Other findings included reticular opacity in two cases, hematoma of the rectus muscle in one, and umbilical hernia in one. Multiloculated fluid collection, ileus, small bowel wall thickening, uneven but smooth peritoneal thickening, and cocoon formation appear to be CT features of CAPD peritonitis

CT and MRI features of acinar cell carcinoma of the pancreas with pathological correlations

International Nuclear Information System (INIS)

Hsu, M.-Y.; Pan, K.-T.; Chu, S.-Y.; Hung, C.-F.; Wu, R.-C.; Tseng, J.-H.

2010-01-01

Aim: To document the computed tomography (CT) and magnetic resonance imaging (MRI) features of acinar cell carcinoma of the pancreas and to correlate them with pathological findings to determine the unique imaging manifestations of this rare subtype tumour of the pancreas. Materials and methods: From January 1986 to August 2008, six patients (five men and one woman, mean age 61.3 years) with histologically proven acinar cell carcinoma of the pancreas underwent CT (n = 6) and MRI (n = 4) examinations. The imaging features of each tumour were documented and compared with pathological findings. Results: The tumours were distributed in the head (n = 4), body (n = 1), and tail (n = 1) of the pancreas. Four masses (67%) were uniformly or partially well-defined with thin, enhancing capsules. Central cystic components were found in five tumours (83%). Two tumours (33%) exhibited intratumoural haemorrhage, and one tumour (17%) had amorphous intratumoural calcification. In both CT and MRI, the tumours enhanced less than the adjacent normal pancreatic parenchyma. The signal intensity on MRI was predominantly T1 hypointense and T2 iso- to hyperintense. Conclusion: Acinar cell carcinoma of the pancreas has distinct imaging features, and both CT and MRI are useful and complementary imaging methods.

68Ga-PSMA-11 Dynamic PET/CT Imaging in Primary Prostate Cancer.

Science.gov (United States)

Sachpekidis, Christos; Kopka, Klaus; Eder, Matthias; Hadaschik, Boris A; Freitag, Martin T; Pan, Leyun; Haberkorn, Uwe; Dimitrakopoulou-Strauss, Antonia

2016-11-01

The aim of our study is to assess the pharmacokinetics and biodistribution of Ga-PSMA-11 in patients suffering from primary prostate cancer (PC) by means of dynamic and whole-body PET/CT. Twenty-four patients with primary, previously untreated PC were enrolled in the study. All patients underwent dynamic PET/CT (dPET/CT) scanning of the pelvis and whole-body PET/CT studies with Ga-PSMA-11. The evaluation of dPET/CT studies was based on qualitative evaluation, SUV calculation, and quantitative analysis based on two-tissue compartment modeling and a noncompartmental approach leading to the extraction of fractal dimension (FD). A total of 23/24 patients (95.8%) were Ga-PSMA-11 positive. In 9/24 patients (37.5%), metastatic lesions were detected. PC-associated lesions demonstrated the following mean values: SUVaverage = 14.3, SUVmax = 23.4, K1 = 0.24 (1/min), k3 = 0.34 (1/min), influx = 0.15 (1/min), and FD = 1.27. The parameters SUVaverage, SUVmax, k3, influx, and FD derived from PC-associated lesions were significantly higher than respective values derived from reference prostate tissue. Time-activity curves derived from PC-associated lesions revealed an increasing Ga-PSMA-11 accumulation during dynamic PET acquisition. Correlation analysis revealed a moderate but significant correlation between PSA levels and SUVaverage (r = 0.60) and SUVmax (r = 0.57), and a weak but significant correlation between Gleason score and SUVaverage (r = 0.33) and SUVmax (r = 0.28). Ga-PSMA-11 PET/CT confirmed its capacity in detecting primary PC with a detection rate of 95.8%. Dynamic PET/CT studies of the pelvis revealed an increase in tracer uptake in PC-associated lesions during the 60 minutes of dynamic PET acquisition, a finding with potential applications in anti-PSMA approaches.

TU-CD-BRB-01: Normal Lung CT Texture Features Improve Predictive Models for Radiation Pneumonitis

International Nuclear Information System (INIS)

Krafft, S; Briere, T; Court, L; Martel, M

2015-01-01

Purpose: Existing normal tissue complication probability (NTCP) models for radiation pneumonitis (RP) traditionally rely on dosimetric and clinical data but are limited in terms of performance and generalizability. Extraction of pre-treatment image features provides a potential new category of data that can improve NTCP models for RP. We consider quantitative measures of total lung CT intensity and texture in a framework for prediction of RP. Methods: Available clinical and dosimetric data was collected for 198 NSCLC patients treated with definitive radiotherapy. Intensity- and texture-based image features were extracted from the T50 phase of the 4D-CT acquired for treatment planning. A total of 3888 features (15 clinical, 175 dosimetric, and 3698 image features) were gathered and considered candidate predictors for modeling of RP grade≥3. A baseline logistic regression model with mean lung dose (MLD) was first considered. Additionally, a least absolute shrinkage and selection operator (LASSO) logistic regression was applied to the set of clinical and dosimetric features, and subsequently to the full set of clinical, dosimetric, and image features. Model performance was assessed by comparing area under the curve (AUC). Results: A simple logistic fit of MLD was an inadequate model of the data (AUC∼0.5). Including clinical and dosimetric parameters within the framework of the LASSO resulted in improved performance (AUC=0.648). Analysis of the full cohort of clinical, dosimetric, and image features provided further and significant improvement in model performance (AUC=0.727). Conclusions: To achieve significant gains in predictive modeling of RP, new categories of data should be considered in addition to clinical and dosimetric features. We have successfully incorporated CT image features into a framework for modeling RP and have demonstrated improved predictive performance. Validation and further investigation of CT image features in the context of RP NTCP

The cryptogenic organizing pneumonia: the analysis of CT features

International Nuclear Information System (INIS)

Zhu Xiaohua; Li Tiannv; You Zhengqian; Ma Jun; Jiang Sen

2007-01-01

Objective: To improve our understanding concerning radiographic manifestations of cryptogenic organizing pneumonia (COP). Methods: The diagnosis of cryptogenic organizing pneumonia was made based on clinical and radiological features, and was verified with lung biopsy and pathological examination in 23 cases. All data were analyzed and relevant literatures were reviewed. Results: CT scans revealed multi- patch shadows, patchy air-space consolidations in 15 cases, often located in predominantly subpleural and(or) both inferior lungs, with or ground-glass opacities, bronchiectasis, and cords. Lesion sites changed over time in some patients. Corticosteroid treatment led to significant improvement in most cases. Conclusions: The diagnosis of cryptogenic organizing pneumonia required the converging evidence from clinical and radiological manifestations as well as pathologies. It is important to appreciate CT manifestations of COP. (authors)

Focal hepatic steatosis: ultrasound and CT scan features may mimick carcinoma of the liver

International Nuclear Information System (INIS)

Monnin, J.L.; Blanc, F.; Guiry, P.; Bruel, J.M.; Monnin, E.; Ciurana, A.J.

1988-01-01

Ultrasound and CT scan features of focal hepatic steatosis (FHS) may closely resemble those of primary or secondary malignant hepatic tumors. Three cases of FHS in chronic alcoholics are reported. In two cases, the area of steatosis was hyperechogenic upon ultrasonography. In all three patients, CT scan demonstrated a hypodense image, with poor enhancement following opacification and no mass effect. Diagnosis of FHS was ascertained upon hepatic biopsy under CT scan guidance in all three patients [fr

Tracheomalacia in adults with cystic fibrosis: determination of prevalence and severity with dynamic cine CT.

LENUS (Irish Health Repository)

McDermott, Shaunagh

2012-02-01

PURPOSE: To determine the prevalence and severity of tracheomalacia in adults with cystic fibrosis (CF) by using dynamic cine multidetector computed tomography (CT) and to correlate these findings with pulmonary function test (PFT) results and the severity of parenchymal lung disease. MATERIALS AND METHODS: In this institutional review board-approved HIPAA-compliant study, 40 patients with CF (22 men, 18 women; mean age, 28 years +\\/- 8 [standard deviation]; age range, 18-54 years) prospectively underwent PFTs, standard thin-section CT, and two dynamic cine multidetector CT acquisitions. Ten control subjects underwent dynamic cine multidetector CT. After standard thin-section CT was completed, dynamic cine multidetector CT was performed during a forced expiratory maneuver and during coughing. Dynamic cine multidetector CT images in nine patients were excluded. Maximal inspiratory, dynamic expiratory, and end-expiratory tracheal luminal areas were compared (Student t test) and correlated (Spearman rank) with PFT results and severity of parenchymal lung disease. RESULTS: Mean predicted forced expiratory volume in 1 second (FEV(1)) was 70.6% +\\/- 20.7, and mean Bhalla CT score was 41.8% +\\/- 13.6. In patients with CF, dynamic cine mean tracheal cross-sectional area reduction was 51.7% +\\/- 18.4 (range, 9%-89%) for forced expiratory maneuvers and 68.8% +\\/- 11.7 (range, 18%-88%) for coughing (P = .001). Tracheomalacia was demonstrated in 24 (69%) patients and no control subjects during forced expiratory maneuvers (P = .001) and in 10 (29%) patients and one (10%) control subject during coughing. For end-expiration images, mean tracheal luminal reduction was 16.1% +\\/- 14.0% (range, 0.0%-53.0%), with one patient demonstrating tracheal luminal reduction of more than 50%. There was no correlation between tracheal cross-sectional luminal reduction and either predicted FEV(1) or CT Bhalla score. CONCLUSION: Tracheomalacia depicted at dynamic cine multidetector CT is a

Diagnosis of pituitary adenoma by dynamic CT scanning

International Nuclear Information System (INIS)

Tanabe, Sumiyoshi; Uede, Teiji; Daibo, Masahiko; Niwa, Jun; Hashi, Kazuo

1988-01-01

The advantage of high resolution CT in the diagnosis of pituitary microadenomas has been established, but the diagnosis becomes more difficult when the pituitary microadenoma is less than 5 mm in diameter. We have studied the usefulness of dynamic CT scans particularly for diagnosis of small microadenomas. The dynamic CT scans were performed for 61 normal pituitary glands and 68 pituitary adenomas (36 microadenomas, 32 macroadenomas) with a GECT/T 9800 scanner. Coronal sections of 1.5 mm thickness were taken at the plane just in front of the pituitary stalk of the pituitary gland. Following a bolus intra-venous injection of 40 - 60 ml of contrast media using an automatic injector, ten consecutive CT scans of 2 seconds scan time were obtained, beginning 2 seconds from the start of intravenous injection. The first seven scans were taken with an interval of 2.3 seconds, and the last three scans with an interval of 10 seconds. Then, time-density curves were obtained at the ROI which were set on the anterior pituitary gland, the vascular bed of the pituitary gland, the pituitary stalk and the area of the pituitary adenoma respectively. In a normal pituitary gland, the density increases gradually and makes an S shaped curve, then attains the maximum density value (92.3 CT number) approximately 60 seconds after the administration of contrast media. The pituitary vascular bed is located in midline on the upper surface of the pituitary gland, and shows a symmetrical square, triangular or rhomboid shape. In case of pituitary adenoma, the time-density curve makes a plateau curve and attains the maximum density value (60.1 CT number) approximately 60 seconds after the administration of contrast media. In microadenoma, the pituitary vascular bed is either deformed or compressed, showing an asymmetrical shape. (author)

Automatic extraction of forward stroke volume using dynamic PET/CT

DEFF Research Database (Denmark)

Harms, Hans; Tolbod, Lars Poulsen; Hansson, Nils Henrik

Background: Dynamic PET can be used to extract forward stroke volume (FSV) by the indicator dilution principle. The technique employed can be automated and is in theory independent on the tracer used and may therefore be added to any dynamic cardiac PET protocol. The aim of this study...... was to validate automated methods for extracting FSV directly from dynamic PET studies for two different tracers and to examine potential scanner hardware bias. Methods: 21 subjects underwent a dynamic 27 min 11C-acetate PET scan on a Siemens Biograph TruePoint 64 PET/CT scanner (scanner I). In addition, 8...... subjects underwent a dynamic 6 min 15O-water PET scan followed by a 27 min 11C-acetate PET scan on a GE Discovery ST PET/CT scanner (scanner II). The LV-aortic time-activity curve (TAC) was extracted automatically from dynamic PET data using cluster analysis. The first-pass peak was isolated by automatic...

Three-dimensional CT features of occipital squama normal anatomy, anatomic variations and fractures

International Nuclear Information System (INIS)

Liu Jungang; Li Xin; Wang Chunxiang; Zhang Lin; Guo Wanhua

2013-01-01

Objective: To evaluate 3D CT features of normal anatomy, anatomic variations and fractures of occipital squama. Methods: The 3D CT features on MIP, VR images were analyzed retrospectively in 589 pediatric cases. The normal anatomy, anatomic variations and fractures of occipital squama were observed respectively, and the differential diagnostic features including the individual location, appearance and extension were analyzed. Results: Four hundred and thirty-three patients (75.2%) showed normal anatomy, including 154 patients with adult occipital anatomical features, 279 patients with posterior intraoccipital synchondrosis, and 37 patients with Kerckring-supraoccipital synchondrosis. When cases with recent trauma history were excluded, 113 patients (19.1%) showed anatomic variants, including unpenetrating sutures and penetrating sutures. The former could be subdivided to Mendosal sutures in 23 cases, superior median fissures in 19 cases, and midline supraoccipital fissures in 4 cases, while the latter could be subdivided to the interparietal bone variations in 54 cases, wormian bones in 23 cases, and accessory bones in 7 cases. Two or more variations coexisted in 33 cases. The occipital squama fractures were shown in 34 cases (5.6%), including linear fractures in 27 cases, comminuted fractures in 3 cases, with depression fracture in one case, separation of cranial sutures in 3 cases, and other fractures associated with variants in 3 cases. The fractures were sharp, or jagged, without limitation of the occification. Conclusion: There are different 3D CT features of normal anatomy, anatomic variations and fractures of occipital squama in children, which are important for making the accurate diagnosis. (authors)

Comparison of AMI-25 enhanced MRI and helical dynamic CT in the detection of hepatic lesions

International Nuclear Information System (INIS)

Saitou, Kazuhiro; Matsuda, Hiromichi; Fukushima, Hiroaki; Kanzaki, Hiroshi; Hirose, Takashi; Karizaki, Dai; Abe, Kimihiko; Amino, Saburou

1994-01-01

We performed AMI-25 enhanced MRI and helical dynamic CT in 12 cases of hepatic lesions. Nine of these were hepatocellular carcinomas. Two cases were metastatic liver tumors (the primary lesion was gastric in one and the other was gallbladder cancer). One case was suspected to be adenomatous hyperplasia. Thirty-two lesions were detected in T2-weighted SE images before AMI-25 administration, while 46 lesions were detected in AMI-25 enhanced MRI images. In particular, AMI-25 enhanced MRI was superior to plain MRI in lesions less than 10 mm in size. A total of 48 lesions were detected in helical dynamic CT. Although AMI-25 enhanced MRI almost equaled helical dynamic CT in the detection of liver tumors, helical dynamic CT was slightly superior to AMI-25 enhanced MRI in the detection of subphrenic lesions. It was possible to know the hemodynamics in each hepatic lesion by helical dynamic CT. AMI-25 enhanced MRI was useful to know the inclusion of reticuloendothelial system, and that yielded different diagnoses in adenomatous hyperplasia and well differentiated hepatocellular carcinoma. Helical dynamic CT was useful for qualitative diagnosis. Both AMI-25 enhanced MRI and helical dynamic CT contributed to the detection of liver tumor and qualitative diagnosis. (author)

CT features of peritonitis carcinomatosa

International Nuclear Information System (INIS)

Ishii, Chikako; Kaneko, Kenji; Kato, Hitonari; Tada, Shinpei

1988-01-01

Fifty patients with peritonitis carcinomatosa were evaluated with computed tomography (CT). CT findings included evidence of mesenteric thickening (60 %), solid mass (20 %), loculated ascites (16 %), ascites (14 %), partly dilated intestine (10 %). Mesenteric thickening showed both intraperitoneal and subperitoneal metastasis. Arrested flow of ascitic fluid (loculated ascites) was one of the most predicting findings of peritonitis carcinomatosa. The seven false negative cases related to small metastatic foci, long distance between autopsy and the last CT examination, or paucity of intraabdominal fat. (author)

CT features and clinical of diffuse axonal injury (with report of 41 cases)

International Nuclear Information System (INIS)

Zhang Yixing

2005-01-01

Objective: To evaluate CT imaging in the diagnosis of diffuse axonal injury (DAI) in correlation with the clinical manifestations. Methods: CT images and clinical data of 41 DAI cases were reviewed retrospectively, including 30 males and 11 females, 15 to 67 years old (average age was 30.5 years). According to the clinical features, all cases were classified into three groups: mild, moderate and severe injury. Results: In 10 cases of mild injury, the major CT findings were cerebral edema, slight cerebral hemorrhage in unilateral hemisphere or sub-arachnoid hemorrhage. Another 15 cases were classified as moderate injury: diffuse cerebral edema and hemorrhage in central brain gray matter were found on CT images. 16 cases with severe injury: severe diffuse cerebral edema accompanied with hemorrhage along the white-gray matter junction as well as epidural hematoma and/or subdural hematoma was demonstrated on CT images. Conclusion: CT scan is valuable in diagnosis of DAI and the anticipation of prognosis. (authors)

Diagnostic value of contrast-enhanced dynamic CT in predicting the malignancy of solitary pulmonary nodules

International Nuclear Information System (INIS)

Goo, Hyun Woo; Song, Koun Sik; Lee, Eun Hye; Kim, Ji Hoon; Lee, Jin Seong; Lim, Tae Hwan

1997-01-01

To determine whether the maximal enhancement time in dynamic CT is different between benign and malignant solitary pulmonary nodules (SPN)s, and to evaluate the value of densitometry on dynamic CT in predicting the malignancy of SPN. Fifty-six patients with SPN of less than 4cm in diameter as seen on chest radiograph and SPN without benign pattern of calcification or fat, as seen on pre-enhance-ment spiral CT scans were included in this study. SPN with small cavitation sufficient to measure CT density, were also included. Thirty-four SPNs were diagnosed pathologically or radiologically as 20 malignant nodules and 14 benign nodules. Dynamic CT was performed by two techniques after injection of 50ml of nonionic contrast media at the rate of 2ml/sec. In 28 patients, incremental dynamic CT was performed before and of 15 seconds, 1 minute, 2 minutes, 3 minutes, and 4 minutes after injection of contrast media during shallow respiration. In 28 patients, double spiral CT was performed 2 minutes and 3 minutes after injection of contrast media during single breath hold. CT readings were taken at the central portion of SPNs, with a circular region of interest. The degree and time of maximal enhancement were recorded. In dynamic CT the maximal enhancement time of SPNs was not significantly different between malignant (2.73±1.27 minute) and benign nodules (2.56±1.24 minute). The enhancement of malignant nodules was significantly greater (21.42±12.17 HU) than of benign nodules (5.15±5.25 HU) (p<.0001). In dynamic CT of SPNs, there is no difference in maximal enhancement time between benign and malignant nodules;enhancement of the latter is significantly greater than that of the former. Maximal enhancement greater than 15 HU can be a good predictor of malignancy of SPNs

Evaluation of Shape and Textural Features from CT as Prognostic Biomarkers in Non-small Cell Lung Cancer.

Science.gov (United States)

Bianconi, Francesco; Fravolini, Mario Luca; Bello-Cerezo, Raquel; Minestrini, Matteo; Scialpi, Michele; Palumbo, Barbara

2018-04-01

We retrospectively investigated the prognostic potential (correlation with overall survival) of 9 shape and 21 textural features from non-contrast-enhanced computed tomography (CT) in patients with non-small-cell lung cancer. We considered a public dataset of 203 individuals with inoperable, histologically- or cytologically-confirmed NSCLC. Three-dimensional shape and textural features from CT were computed using proprietary code and their prognostic potential evaluated through four different statistical protocols. Volume and grey-level run length matrix (GLRLM) run length non-uniformity were the only two features to pass all four protocols. Both features correlated negatively with overall survival. The results also showed a strong dependence on the evaluation protocol used. Tumour volume and GLRLM run-length non-uniformity from CT were the best predictor of survival in patients with non-small-cell lung cancer. We did not find enough evidence to claim a relationship with survival for the other features. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

CT features of pulmonary mycobacterial disease in patients with acquired immunodeficiency syndrome

International Nuclear Information System (INIS)

Zhu Ying; Zhang Zhiyong; Shi Yuxin; Feng Feng

2013-01-01

Objective: To study the CT features of pulmonary non-tuberculous mycobacteria (NTM) disease in patients with acquired immunodeficiency syndrome (AIDS) and explore the different CT appearances between AIDS-NTM and AIDS-TB. Methods: CT findings of pulmonary NTM disease in 27 AIDS patients (NTM group) were retrospectively analyzed and compared with that of tuberculosis in 30 AIDS patients (TB group). The results were statistically analyzed using Fisher's exact test. Results: CT findings of NTM appeared significantly more than that of TB as follows: high-density nodules (n = 18 vs 1, P < 0.01), ground-glass opacities (n = 10 vs 0, P < 0.01), fibrotic band (n = 17 vs 3, P < 0.01), bronchiectasis (9 vs 2, P = 0.012). CT findings of NTM appeared significantly less than that of TB as follows: miliary nodules (0 vs 6, P = 0.016), air space consolidations (n = 2 vs 11, P < 0.01), pleural effusion (n = 1 vs 9, P < 0.01). Conclusion: Nodule and fibrotic band accompanied with bronchiectasis were the main CT manifestations of pulmonary NTM disease in AIDS patients, while air space consolidation accompanied with pleural effusion and miliary nodules were the predominate CT findings of pulmonary tuberculosis in AIDS patients. (authors)

Cardiovascular disease prediction: do pulmonary disease-related chest CT features have added value?

International Nuclear Information System (INIS)

Jairam, Pushpa M.; Jong, Pim A. de; Mali, Willem P.T.M.; Isgum, Ivana; Graaf, Yolanda van der

2015-01-01

Certain pulmonary diseases are associated with cardiovascular disease (CVD). Therefore we investigated the incremental predictive value of pulmonary, mediastinal and pleural features over cardiovascular imaging findings. A total of 10,410 patients underwent diagnostic chest CT for non-cardiovascular indications. Using a case-cohort approach, we visually graded CTs from the cases and from an approximately 10 % random sample of the baseline cohort (n = 1,203) for cardiovascular, pulmonary, mediastinal and pleural findings. The incremental value of pulmonary disease-related CT findings above cardiovascular imaging findings in cardiovascular event risk prediction was quantified by comparing discrimination and reclassification. During a mean follow-up of 3.7 years (max. 7.0 years), 1,148 CVD events (cases) were identified. Addition of pulmonary, mediastinal and pleural features to a cardiovascular imaging findings-based prediction model led to marginal improvement of discrimination (increase in c-index from 0.72 (95 % CI 0.71-0.74) to 0.74 (95 % CI 0.72-0.75)) and reclassification measures (net reclassification index 6.5 % (p < 0.01)). Pulmonary, mediastinal and pleural features have limited predictive value in the identification of subjects at high risk of CVD events beyond cardiovascular findings on diagnostic chest CT scans. (orig.)

Cardiovascular disease prediction: do pulmonary disease-related chest CT features have added value?

Energy Technology Data Exchange (ETDEWEB)

Jairam, Pushpa M. [University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Jong, Pim A. de; Mali, Willem P.T.M. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Isgum, Ivana [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Graaf, Yolanda van der [University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); Collaboration: PROVIDI study-group

2015-06-01

Certain pulmonary diseases are associated with cardiovascular disease (CVD). Therefore we investigated the incremental predictive value of pulmonary, mediastinal and pleural features over cardiovascular imaging findings. A total of 10,410 patients underwent diagnostic chest CT for non-cardiovascular indications. Using a case-cohort approach, we visually graded CTs from the cases and from an approximately 10 % random sample of the baseline cohort (n = 1,203) for cardiovascular, pulmonary, mediastinal and pleural findings. The incremental value of pulmonary disease-related CT findings above cardiovascular imaging findings in cardiovascular event risk prediction was quantified by comparing discrimination and reclassification. During a mean follow-up of 3.7 years (max. 7.0 years), 1,148 CVD events (cases) were identified. Addition of pulmonary, mediastinal and pleural features to a cardiovascular imaging findings-based prediction model led to marginal improvement of discrimination (increase in c-index from 0.72 (95 % CI 0.71-0.74) to 0.74 (95 % CI 0.72-0.75)) and reclassification measures (net reclassification index 6.5 % (p < 0.01)). Pulmonary, mediastinal and pleural features have limited predictive value in the identification of subjects at high risk of CVD events beyond cardiovascular findings on diagnostic chest CT scans. (orig.)

Isoattenuating insulinomas at biphasic contrast-enhanced CT: frequency, clinicopathologic features and perfusion characteristics

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Zhu, Liang; Xue, Hua-dan; Sun, Hao; Wang, Xuan; He, Yong-lan; Jin, Zheng-yu [Peking Union Medical College Hospital, Department of Radiology, Beijing (China); Zhao, Yu-pei [Peking Union Medical College Hospital, Department of General Surgery, Beijing (China)

2016-10-15

We aimed to determine the frequency of isoattenuating insulinomas, to investigate their clinicopathological features and to assess their regional pancreatic perfusion characteristics. Institutional review board approval was obtained, and patient informed consent was waived. From July 2010 to June 2014, 170 patients (66 male, 104 female) with endogenous hyperinsulinemic hypoglycemia underwent biphasic contrast-enhanced CT before surgery, and 129 of those patients also received preoperative whole-pancreas CT perfusion. A total of 181 tumours were proved histopathologically after surgery. Enhancement pattern and regional pancreatic perfusion characteristics were analyzed. Clinical features, tumour size and pathological grading were investigated. The frequency of isoattenuating tumours was 24.9 %. Tumour size and WHO grading was not significantly different between isoattenuating and hyperattenuating tumours. Tumour-free regions had identical blood flow (BF) regardless of their location (p = 0.35). Isoattenuating tumour-harbouring regions had lower BF compared with hyperattenuating tumour-harbouring regions; both showed higher BF compared with tumour-free neighbourhood regions (all p < 0.01). For patients with isoattenuating tumours, the overall hospital stay was longer (p < 0.01). A substantial subset of insulinomas were isoattenuating on biphasic CT. CT perfusion showed higher BF in tumour-harbouring regions compared to tumour-free regions, providing a clue for tumour regionalization. (orig.)

CT features of lung cancer associated with idiopathic pulmonary fibrosis

International Nuclear Information System (INIS)

Kim, Jun Hyoung; Song, Koun Sik; Lee, Deok Hee; Kim, Jin Suh; Lim, Tae Hwan

1996-01-01

It is well known that the incidence of lung cancer is high in patients with idiopathic pulmonary fibrosis(IPF). We analyzed the CT features of lung cancer associated with IPF. Retrospective analyzed the CT features of lung cancer associated with IPF. Retrospective analysis was performed in 23 patients with lung cancer(24 lung cancers) associated with IPF. The diagnosis of IPF was made by clinical and CT findings, and lung cancer was confirmed pathologically. We divided the location of lung cancer by lobar distribution and central or peripheral lung zone, and measured the size of mass. We classified the mediastinal lymph node enlargement by American Thoracic Society (ATS) mapping scheme. We evaluated the CT pattern of IPF. The subjects consisted of 6 cases of small cell carcinoma and 18 cases of non-small cell lung cancer. Non-small cell lung cancers were located in the right upper lobe in 5 cases, left upper lobe in 6 cases, right middle lobe in 1 case, right lower lobe in 9 cases, and left lower lobe in 3 cases. Twenty cancers(85%) were located in the peripheral lung zone. Eighteen cancers(73%) were surrounded by fibrotic lung. The size of the mass ranged from 1 to 12 cm, and in 12 cases it was below 3cm in diameter. Mediastinal lymph nodes were enlarged in 22 cases(92%) and classified as N2 or N3 in 15 cases out of 18 non-small cell lung. The size of the mass ranged from 1 to 12 cm, and in 12 cases it was below 3 cm in diameter. Mediastinal lymph nodes were enlarged in 22 cases(92%) and classified as N2 or N3 in 15 cases out of 18 non-small cell lung cancers. CT patterns of underlying IPF were honey-combing in 18 patients(78%) and mixed honey-combing and ground-glass opacity in 5 patients(22%). The lung cancer associated with IPF shows variable cell types. Most of the lung cancers were located peripherally, surrounded by end-stage fibrosis, and were associated with mediastinal lymph node enlargement

CT features of lung cancer associated with idiopathic pulmonary fibrosis

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Kim, Jun Hyoung; Song, Koun Sik; Lee, Deok Hee; Kim, Jin Suh; Lim, Tae Hwan [Ulsan Univ. College of Medicine, Seoul (Korea, Republic of)

1996-01-01

It is well known that the incidence of lung cancer is high in patients with idiopathic pulmonary fibrosis(IPF). We analyzed the CT features of lung cancer associated with IPF. Retrospective analyzed the CT features of lung cancer associated with IPF. Retrospective analysis was performed in 23 patients with lung cancer(24 lung cancers) associated with IPF. The diagnosis of IPF was made by clinical and CT findings, and lung cancer was confirmed pathologically. We divided the location of lung cancer by lobar distribution and central or peripheral lung zone, and measured the size of mass. We classified the mediastinal lymph node enlargement by American Thoracic Society (ATS) mapping scheme. We evaluated the CT pattern of IPF. The subjects consisted of 6 cases of small cell carcinoma and 18 cases of non-small cell lung cancer. Non-small cell lung cancers were located in the right upper lobe in 5 cases, left upper lobe in 6 cases, right middle lobe in 1 case, right lower lobe in 9 cases, and left lower lobe in 3 cases. Twenty cancers(85%) were located in the peripheral lung zone. Eighteen cancers(73%) were surrounded by fibrotic lung. The size of the mass ranged from 1 to 12 cm, and in 12 cases it was below 3cm in diameter. Mediastinal lymph nodes were enlarged in 22 cases(92%) and classified as N2 or N3 in 15 cases out of 18 non-small cell lung. The size of the mass ranged from 1 to 12 cm, and in 12 cases it was below 3 cm in diameter. Mediastinal lymph nodes were enlarged in 22 cases(92%) and classified as N2 or N3 in 15 cases out of 18 non-small cell lung cancers. CT patterns of underlying IPF were honey-combing in 18 patients(78%) and mixed honey-combing and ground-glass opacity in 5 patients(22%). The lung cancer associated with IPF shows variable cell types. Most of the lung cancers were located peripherally, surrounded by end-stage fibrosis, and were associated with mediastinal lymph node enlargement.

An Accurate CT Saturation Classification Using a Deep Learning Approach Based on Unsupervised Feature Extraction and Supervised Fine-Tuning Strategy

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Muhammad Ali

2017-11-01

Full Text Available Current transformer (CT saturation is one of the significant problems for protection engineers. If CT saturation is not tackled properly, it can cause a disastrous effect on the stability of the power system, and may even create a complete blackout. To cope with CT saturation properly, an accurate detection or classification should be preceded. Recently, deep learning (DL methods have brought a subversive revolution in the field of artificial intelligence (AI. This paper presents a new DL classification method based on unsupervised feature extraction and supervised fine-tuning strategy to classify the saturated and unsaturated regions in case of CT saturation. In other words, if protection system is subjected to a CT saturation, proposed method will correctly classify the different levels of saturation with a high accuracy. Traditional AI methods are mostly based on supervised learning and rely heavily on human crafted features. This paper contributes to an unsupervised feature extraction, using autoencoders and deep neural networks (DNNs to extract features automatically without prior knowledge of optimal features. To validate the effectiveness of proposed method, a variety of simulation tests are conducted, and classification results are analyzed using standard classification metrics. Simulation results confirm that proposed method classifies the different levels of CT saturation with a remarkable accuracy and has unique feature extraction capabilities. Lastly, we provided a potential future research direction to conclude this paper.

Intraductal papillary mucinous neoplasms of the pancreas: Correlation of helical CT features with pathologic findings

International Nuclear Information System (INIS)

Liu Yu; Lin Xiaozhu; Upadhyaya, Manavendra; Song Qi; Chen Kemin

2010-01-01

Objective: To evaluate the CT features of intraductal papillary mucinous neoplasms of the pancreas (IPMNs), and to compare with pathological findings in order to identify CT features that can be helpful in differentiating benign IPMNs from malignant IPMNs. Materials and methods: The CT findings in 25 patients were reviewed for tumor location, tumor type, dilatation of the main pancreatic duct (MPD), MPD involvement, mural node or solid attenuating component, tumor size in branch duct or mixed duct type, dilatation of common bile duct (CBD) and invasion of surrounding structures. The data was subjected to Chi-Square Tests or Fisher's Exact Test using SPSS13.0 software with p value < 0.05 indicating significant statistical difference. Results: Presence of mural node or solid enhancing component, size of mural node or solid enhancing component ≥7 mm, dilatation of CBD was more common in malignant IPMNs (p < 0.05). None of tumor location, tumor type, dilatation of MPD, MPD involvement, tumor size, and invasion of surrounding structures was statistically significant in differentiating benign from malignant IPMNs. Conclusions: CT features suggestive of malignant or invasive IPMNs include presence of mural node or solid enhancing component, size of mural node or solid enhancing component ≥7 mm, and dilatation of CBD.

Predicting CT Image From MRI Data Through Feature Matching With Learned Nonlinear Local Descriptors.

Science.gov (United States)

Yang, Wei; Zhong, Liming; Chen, Yang; Lin, Liyan; Lu, Zhentai; Liu, Shupeng; Wu, Yao; Feng, Qianjin; Chen, Wufan

2018-04-01

Attenuation correction for positron-emission tomography (PET)/magnetic resonance (MR) hybrid imaging systems and dose planning for MR-based radiation therapy remain challenging due to insufficient high-energy photon attenuation information. We present a novel approach that uses the learned nonlinear local descriptors and feature matching to predict pseudo computed tomography (pCT) images from T1-weighted and T2-weighted magnetic resonance imaging (MRI) data. The nonlinear local descriptors are obtained by projecting the linear descriptors into the nonlinear high-dimensional space using an explicit feature map and low-rank approximation with supervised manifold regularization. The nearest neighbors of each local descriptor in the input MR images are searched in a constrained spatial range of the MR images among the training dataset. Then the pCT patches are estimated through k-nearest neighbor regression. The proposed method for pCT prediction is quantitatively analyzed on a dataset consisting of paired brain MRI and CT images from 13 subjects. Our method generates pCT images with a mean absolute error (MAE) of 75.25 ± 18.05 Hounsfield units, a peak signal-to-noise ratio of 30.87 ± 1.15 dB, a relative MAE of 1.56 ± 0.5% in PET attenuation correction, and a dose relative structure volume difference of 0.055 ± 0.107% in , as compared with true CT. The experimental results also show that our method outperforms four state-of-the-art methods.

Computed tomography of liver tumors, 2. Differential diagnosis between hepatocellular carcinoma and metastatic hepatic tumor by dynamic CT scanning

Energy Technology Data Exchange (ETDEWEB)

Naito, Akira; Fukuoka, Haruhito; Kashiwado, Kouzou; Ichiki, Toshio; Makidono, Yoko [Hiroshima Red Cross Hospital (Japan)

1984-02-01

Differential diagnosis between hepatocellular carcinoma and metastatic hepatic tumor was attempted using dynamic CT scanning. Homogeneous and patchy types were peculiar to hepatocellular carcinoma, and ring-like type to metastatic hepatic tumor. However, with no enhancement, hepatocellular carcinoma could not be denied. Hepatocellular carcinoma was characterized by the enhancement shown on the early stage of dynamic CT. Ring enhancement was not visualized on dynamic CT but visualized on conventional contrast enhanced CT in hepatocellular carcinomas; it was visualized on conventional contrast enhanced CT and on dynamic CT in metastatic hepatic tumors.

CT imaging of hepatic veno-occlusive disease (an analysis 14 cases)

International Nuclear Information System (INIS)

Zhang Guohua; Kong Azhao; Fang Junwei; Chen Yuejing; Zheng Weiliang; Dong Danjun; Zhang Shizheng

2006-01-01

Objective: To probe imaging characteristics of the hepatic veno-occlusive disease (VOD) based on clinical features and abdomen CT findings. Methods: Fourteen patients including 6 male and 8 female aged from 41 to 73 years were enrolled in this study. They all had previous trauma history and notoginseng was given as herbal remedy. Dynamic enhanced CT and color Dopplor ultrasound examinations were routinely used. Two of them received venous angiography and four cases were pathologically proved as VOD after CT guided needle biopsy. Results: Hepatic swelling and ascites were found on plain CT scan. Diffuse patchy areas without enhancement indicative of poorly hepatic perfusion were found. Hepatic veins were compressed and became thin, and inferior vena cava was flat and narrow without distal dilation or collateral circulation. No obstruction of hepatic veins and inferior vena cava was found on ultrasound and venography. Conclusion: Dynamic enhanced CT is highly valuable for early assessing VOD and imaging features of venous hepatic congestion found on CT was strongly suggestive of VOD if there's previous history of treatment of gynura segetum. (authors)

The characteristics of cerebral meningiomas and surrounding tissues on dynamic CT

International Nuclear Information System (INIS)

Jinkins, J.R.; Sener, R.N.

1991-01-01

Dynamic CT was utilized to evaluate 11 patients with histologically benign meningiomas. While it was found that all demonstrated macroscopic neovascularity, subtle differences in the dynamic perfusion curves were identified both between different meningiomas and from region to region within the same tumor. Other than basic anatomic differences, these changes may reflect intratumoral ischemia and hypothetically herald cystic/necrotic alteration within the neoplasm. The dynamic calculations over the surrounding brain showed areas of gross hyper- and hypoperfused cerebral cortex, and hypoperfused white matter in regions of peritumoral edema. These latter findings are of uncertain clinical importance. The dynamic examination also confirmed cases of dural venous sinus invasion and calvarial permeation by tumor. In addition, the dynamic series showed macroscopic neovascularity in one case with a completely negative selective cerebral arteriogram. It is felt that certain cases which have previously been evaluated by static CT may benefit from further study utilizing the dynamic method. (orig.)

Serial dynamic CT scan in patients with acute basal ganglia infarctions

International Nuclear Information System (INIS)

Node, Yoji; Nakazawa, Shozo; Tsuji, Yukihide.

1987-01-01

Dynamic computed tomography (CT) was performed on 15 patients (37 to 93 years of age) with acute basal ganglia infarctions, and the perfusion patterns of the infarcted regions on CT were evaluated. The initial dynamic CT was performed within 12 hours after onset, while the serial studies of the dynamic CT were performed on the 3rd and 7th days. The left-over-right ratio in the peak value in the basal ganglia in 15 normal subjects was 1.01 ± 0.03 (mean ± SD), so there were no differences in the peak values of the bilateral basal ganglia. We also examined the left-over-right ratio in the peak value and in the rapid-washout ratio in the basal ganglia in the 15 normal subjects. There was no difference in the peak values of the bilateral basal ganglia. The mean rapid-washout ratio was 0.62 ± 0.11 (mean ± SD). The prognoses of these patients three months after onset were as follows: 8 showed a good recovery, 5 had a moderate disability, and 2 had a severe disability. The perfusions on admission were as follows. 10 were hypoperfusions, 3 were hypo + late perfusions, one was a normoperfusion, and one was a late perfusion. There was a tendency for the rapid-washout ratio decrease more in the hypo + late perfusion group than in the other groups. Twelve patients showed an iso-density, while 3 showed a low density, on admission. The ''low-density'' group showed a decrease in the A/N ratio of the peak value. We performed serial dynamic CT in 11 cases. The group with severe disabilities (2 cases) showed a hypo + late perfusion in the initial CT, one case kept a hypo + late perfusion, and another case changed to a hypoperfusion; also, there was a tendency for there to be a poor improvement in the A/N ratio of the peak value in these two ''severe-disability'' patients. (J.P.N.)

Warthin's Tumor of the Parotid Gland: CT and MR Features

International Nuclear Information System (INIS)

Lee, Yun Hee; Yu, In Kyu; Lee, Byung Hee; Kim, Min Sun; Han, Moon Hee; Song, Chang Joon

2009-01-01

In this study, we have evaluated the imaging features of Warthin's tumor of the parotid gland with the use of CT and MR imaging. CT (n = 30) and MR (n = 7) images of 26 patients (M:F=23:3; age range, 38-76 years; mean age, 58 years) with surgically-proven Warthin's tumor (n = 37) were reviewed with a focus on bilaterality, multiplicity, location, size, demarcation, margin, enhancement pattern and MR signal intensity. Lesions were bilateral in seven patients (27%), multiple in nine patients (35%) and unilateral multiple in four patients (15%). Tumors were located in the superficial lobe (65%), deep lobe (24%) and both lobes (11%) of the parotid gland. Most tumors had a clear (95%) and smooth margin (95%) with a round or oval shape. Tumors mainly showed a solid and cystic composition (n = 24, 65%) and all solid stroma showed poor or weak enhancement on both CT and MR images. Papillary projections from the peripheral wall were clearly seen (n = 6, 86%). Warthin's tumor is frequently seen in the parotid superficial lobe of older males with a higher bilateral and multiple tendency. Warthin's tumor shows cystic portions with papillary projections at the wall on CT images and focal high signal intensity (SI) on T1-weighted images with dense nodular enhancement on MR images

CT features of invasion of sublingual space by malignant oropharyngeal tumors

International Nuclear Information System (INIS)

Wei Yi; Xiao Jiahe; Zhou Xiangping; Deng Kaihong

2003-01-01

Objective: To investigate the CT features of the invasion of sublingual space by malignant oropharyngeal tumors in order to provide more accurate information for clinical treatment. Methods: Fifty-eight cases of pathologically proven malignant oropharyngeal tumors were collected and retrospectively analyzed. Results: Among all the cases, invasion of sublingual space by malignant oropharyngeal tumors could be seen in 14 cases, of which, 7 cases got access to sublingual space through tongue base, 3 cases through parapharyngeal space, 2 cases through pterygomandibular raphe, 2 cases through uncertain routes. Invasion of sublingual space manifested on CT scan as obliteration of fat plane in sublingual space and involvement of the sublingual vessels in the space. Conclusion: Malignant oropharyngeal tumors can invade the adjacent sublingual space via tongue base, pterygomandibular raphe, and parapharyngeal space. The invasion of sublingual space by malignant oropharyngeal tumors manifests in CT as effacement of sublingual fat plane and envelopment of hyoid artery

Comparison of quantitatively analyzed dynamic area-detector CT using various mathematic methods with FDG PET/CT in management of solitary pulmonary nodules.

Science.gov (United States)

Ohno, Yoshiharu; Nishio, Mizuho; Koyama, Hisanobu; Fujisawa, Yasuko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

2013-06-01

The objective of our study was to prospectively compare the capability of dynamic area-detector CT analyzed with different mathematic methods and PET/CT in the management of pulmonary nodules. Fifty-two consecutive patients with 96 pulmonary nodules underwent dynamic area-detector CT, PET/CT, and microbacterial or pathologic examinations. All nodules were classified into the following groups: malignant nodules (n = 57), benign nodules with low biologic activity (n = 15), and benign nodules with high biologic activity (n = 24). On dynamic area-detector CT, the total, pulmonary arterial, and systemic arterial perfusions were calculated using the dual-input maximum slope method; perfusion was calculated using the single-input maximum slope method; and extraction fraction and blood volume (BV) were calculated using the Patlak plot method. All indexes were statistically compared among the three nodule groups. Then, receiver operating characteristic analyses were used to compare the diagnostic capabilities of the maximum standardized uptake value (SUVmax) and each perfusion parameter having a significant difference between malignant and benign nodules. Finally, the diagnostic performances of the indexes were compared by means of the McNemar test. No adverse effects were observed in this study. All indexes except extraction fraction and BV, both of which were calculated using the Patlak plot method, showed significant differences among the three groups (p method, pulmonary arterial perfusion calculated using the dual-input method, and perfusion calculated using the single-input method were significantly larger than that of SUVmax (p method (69.8%, p method has better potential for the diagnosis of pulmonary nodules than dynamic area-detector CT analyzed using other methods and than PET/CT.

TH-E-BRF-04: Characterizing the Response of Texture-Based CT Image Features for Quantification of Radiation-Induced Normal Lung Damage

International Nuclear Information System (INIS)

Krafft, S; Court, L; Briere, T; Martel, M

2014-01-01

Purpose: Radiation induced lung damage (RILD) is an important dose-limiting toxicity for patients treated with radiation therapy. Scoring systems for RILD are subjective and limit our ability to find robust predictors of toxicity. We investigate the dose and time-related response for texture-based lung CT image features that serve as potential quantitative measures of RILD. Methods: Pre- and post-RT diagnostic imaging studies were collected for retrospective analysis of 21 patients treated with photon or proton radiotherapy for NSCLC. Total lung and selected isodose contours (0–5, 5–15, 15–25Gy, etc.) were deformably registered from the treatment planning scan to the pre-RT and available follow-up CT studies for each patient. A CT image analysis framework was utilized to extract 3698 unique texture-based features (including co-occurrence and run length matrices) for each region of interest defined by the isodose contours and the total lung volume. Linear mixed models were fit to determine the relationship between feature change (relative to pre-RT), planned dose and time post-RT. Results: Seventy-three follow-up CT scans from 21 patients (median: 3 scans/patient) were analyzed to describe CT image feature change. At the p=0.05 level, dose affected feature change in 2706 (73.1%) of the available features. Similarly, time affected feature change in 408 (11.0%) of the available features. Both dose and time were significant predictors of feature change in a total of 231 (6.2%) of the extracted image features. Conclusion: Characterizing the dose and time-related response of a large number of texture-based CT image features is the first step toward identifying objective measures of lung toxicity necessary for assessment and prediction of RILD. There is evidence that numerous features are sensitive to both the radiation dose and time after RT. Beyond characterizing feature response, further investigation is warranted to determine the utility of these features as

Significance and problems of the dynamic CT scan for the diagnosis and treatment of cerebral infarctions

International Nuclear Information System (INIS)

Morita, Akio; Teraoka, Akira

1985-01-01

Dynamic CT scan is a very useful method for the diagnosis of cerebral infarctions and other ischemic disorders. We have used this method for 1) the ultra-early stage diagnosis of major infarctions, 2) the detection of the recanalization and the disruption of the blood-brain barrier, and 3) the detection of latent ischemic lesions. In this report we discussed the clinical cases and the usual use of this dynamic CT scan. We used a GE CT/T8800 scanner for dynamic CT scanning. Manual bolus-contrast-medium injection was done simultaneously with the first scanning, and 6 sequential scannings (scan time: 4.8 s; scan interval: 1.4 s) were done on the same slice level. Especially in major infarctions (e.g., MCA occlusion), OM 40 was the most preferred slice. In cases of ultra-early stage infarctions (i.e., no abnormal lesions in non-enhanced CT), we used this dynamic CT scan immediately after the non-enhanced CT; we could thus obtain information on the ischemic lesions and the ischemic degree. After that we repeated this examination on Days 3, 7, and 14 for the evaluation of the recanalization and blood-brain-barrier disruption. In the cases of TIA and impending or progressing strokes, dynamic CT scan could disclose latent ischemic lesions; in there instances, we treated the patients with intensive to prevent the prognosis from worsening. These benefits and also some problems were discussed. (author)

Comparison of blood flow models and acquisitions for quantitative myocardial perfusion estimation from dynamic CT

International Nuclear Information System (INIS)

Bindschadler, Michael; Alessio, Adam M; Modgil, Dimple; La Riviere, Patrick J; Branch, Kelley R

2014-01-01

Myocardial blood flow (MBF) can be estimated from dynamic contrast enhanced (DCE) cardiac CT acquisitions, leading to quantitative assessment of regional perfusion. The need for low radiation dose and the lack of consensus on MBF estimation methods motivates this study to refine the selection of acquisition protocols and models for CT-derived MBF. DCE cardiac CT acquisitions were simulated for a range of flow states (MBF = 0.5, 1, 2, 3 ml (min g) −1 , cardiac output = 3, 5, 8 L min −1 ). Patient kinetics were generated by a mathematical model of iodine exchange incorporating numerous physiological features including heterogenenous microvascular flow, permeability and capillary contrast gradients. CT acquisitions were simulated for multiple realizations of realistic x-ray flux levels. CT acquisitions that reduce radiation exposure were implemented by varying both temporal sampling (1, 2, and 3 s sampling intervals) and tube currents (140, 70, and 25 mAs). For all acquisitions, we compared three quantitative MBF estimation methods (two-compartment model, an axially-distributed model, and the adiabatic approximation to the tissue homogeneous model) and a qualitative slope-based method. In total, over 11 000 time attenuation curves were used to evaluate MBF estimation in multiple patient and imaging scenarios. After iodine-based beam hardening correction, the slope method consistently underestimated flow by on average 47.5% and the quantitative models provided estimates with less than 6.5% average bias and increasing variance with increasing dose reductions. The three quantitative models performed equally well, offering estimates with essentially identical root mean squared error (RMSE) for matched acquisitions. MBF estimates using the qualitative slope method were inferior in terms of bias and RMSE compared to the quantitative methods. MBF estimate error was equal at matched dose reductions for all quantitative methods and range of techniques evaluated. This

Differentiating pre- and minimally invasive from invasive adenocarcinoma using CT-features in persistent pulmonary part-solid nodules in Caucasian patients

International Nuclear Information System (INIS)

Cohen, Julien G.; Reymond, Emilie; Lederlin, Mathieu; Medici, Maud; Lantuejoul, Sylvie; Laurent, François; Arbib, François; Jankowski, Adrien

2015-01-01

Highlights: •We analyzed CT-features of part-solid ground glass nodules in Caucasians. •These CT-features were compared to pathology on full resection specimen. •Several CT-features can help differentiating invasive adenocarcinoma. •A solid component larger than 5 mm had 100% sensitivity for invasive adenocarcinoma. -- Abstract: Objective: To retrospectively investigate the diagnostic value of pre-operative CT-features between pre/minimally invasive and invasive lesions in part-solid persistent pulmonary ground glass nodules in a Caucasian population. Materials and methods: Retrospective review of two pre-operative CTs for 31 nodules in 30 patients. There were 10 adenocarcinomas in situ, 1 minimally invasive adenocarcinoma, 20 invasive adenocarcinomas. We analyzed the correlation between histopathology and the following CT-features: maximal axial diameter, maximal orthogonal axial diameter, height, density, size of solid component, air bronchogram, pleural retraction, nodule mass, disappearance rate and their evolution during follow-up. Results: In univariate analysis, invasive adenocarcinomas had a higher maximal height, density, solid component size, mass, a lower disappearance rate and presented more often with pleural retraction (p < 0.05). After logistic regression performed with the uncorrelated parameters using a method of selection of variables, only the size of solid component remained significant, with 100% sensitivity for invasive adenocarcinoma when larger than 5 mm. Conclusion: Preoperative CT-features can help differentiating in situ and minimally invasive adenocarcinomas from invasive adenocarcinomas in Caucasian patients. A solid component larger than 5 mm in diameter had 100% sensitivity for the diagnosis of invasive adenocarcinoma

Differentiating pre- and minimally invasive from invasive adenocarcinoma using CT-features in persistent pulmonary part-solid nodules in Caucasian patients

Energy Technology Data Exchange (ETDEWEB)

Cohen, Julien G., E-mail: JCohen@chu-grenoble.fr [Clinique Universitaire de Radiologie et Imagerie Médicale (CURIM), Université Joseph Fourier, Centre Hospitalier Universitaire de Grenoble, CS 10217, 38043 Grenoble Cedex 9 (France); Reymond, Emilie [Clinique Universitaire de Radiologie et Imagerie Médicale (CURIM), Université Joseph Fourier, Centre Hospitalier Universitaire de Grenoble, CS 10217, 38043 Grenoble Cedex 9 (France); Lederlin, Mathieu [Service de Radiologie, Université Segalen Bordeaux, Centre Hospitalier Universitaire de Bordeaux, 12 rue Dubernat, 33404 Bordeaux Cedex (France); Medici, Maud [Centre d’Investigation Clinique – Innovation Technologique (CIC-IT), Pavillon Taillefer, 38706 La Tronche Cedex (France); Lantuejoul, Sylvie [Departement d’Anatomie et Cytologie Pathologique (DACP), Université Joseph Fourier, Centre Hospitalier Universitaire de Grenoble, CS 10217, 38043 Grenoble Cedex 9 (France); Laurent, François [Service de Radiologie, Université Segalen Bordeaux, Centre Hospitalier Universitaire de Bordeaux, 12 rue Dubernat, 33404 Bordeaux Cedex (France); Arbib, François [Departement de Pneumologie, Université Joseph Fourier, Centre Hospitalier Universitaire de Grenoble, CS 10217, 38043 Grenoble Cedex 9 (France); Jankowski, Adrien [Clinique Universitaire de Radiologie et Imagerie Médicale (CURIM), Université Joseph Fourier, Centre Hospitalier Universitaire de Grenoble, CS 10217, 38043 Grenoble Cedex 9 (France); and others

2015-04-15

Highlights: •We analyzed CT-features of part-solid ground glass nodules in Caucasians. •These CT-features were compared to pathology on full resection specimen. •Several CT-features can help differentiating invasive adenocarcinoma. •A solid component larger than 5 mm had 100% sensitivity for invasive adenocarcinoma. -- Abstract: Objective: To retrospectively investigate the diagnostic value of pre-operative CT-features between pre/minimally invasive and invasive lesions in part-solid persistent pulmonary ground glass nodules in a Caucasian population. Materials and methods: Retrospective review of two pre-operative CTs for 31 nodules in 30 patients. There were 10 adenocarcinomas in situ, 1 minimally invasive adenocarcinoma, 20 invasive adenocarcinomas. We analyzed the correlation between histopathology and the following CT-features: maximal axial diameter, maximal orthogonal axial diameter, height, density, size of solid component, air bronchogram, pleural retraction, nodule mass, disappearance rate and their evolution during follow-up. Results: In univariate analysis, invasive adenocarcinomas had a higher maximal height, density, solid component size, mass, a lower disappearance rate and presented more often with pleural retraction (p < 0.05). After logistic regression performed with the uncorrelated parameters using a method of selection of variables, only the size of solid component remained significant, with 100% sensitivity for invasive adenocarcinoma when larger than 5 mm. Conclusion: Preoperative CT-features can help differentiating in situ and minimally invasive adenocarcinomas from invasive adenocarcinomas in Caucasian patients. A solid component larger than 5 mm in diameter had 100% sensitivity for the diagnosis of invasive adenocarcinoma.

CT and MRI features in bipolaris fungal sinusitis

International Nuclear Information System (INIS)

Aribandi, M.; Bazan III, C.

2007-01-01

Bipolaris is an increasingly recognized cause of fungal sinusitis. Reports of imaging features are sparse. Our purpose was to review the imaging features in patients with Bipolaris fungal sinusitis. A review of our data showed seven patients with culture-proven Bipolaris fungal sinusitis. Computed tomography of the paranasal sinuses in all the patients and MRI in five patients were analysed for the location, nature, extent of the disease and density/ signal characteristics on CT/MRI. The sphenoid and posterior ethmoid sinuses were most often involved (six of seven), followed by the anterior ethmoid sinus (five of seven), frontal sinus (four of seven) and maxillary sinus (three of seven) involvement. Five of seven cases had bilateral disease. Secretions were seen to fill the sinus and were expansile in nature in six of seven cases. Bony erosion was noted in all the patients. Air-fluid levels and bony sclerosis were rarely seen. Computed tomography showed central hyperdensity in all the cases. In the corresponding MR images (n = 5), the sinus contents appeared hyperintense on T1-weighted images and hypointense on T2-weighted images. Extension into the nasal cavity was found in six of seven cases. Five of seven cases had intracranial (extradural) spread. Intraorbital extension was seen in three of seven cases, with associated optic nerve compression in two. All the patients responded to surgical debridement, and systemic antifungal therapy was not required. Bipolaris fungal sinusitis typically presents with an allergic fungal sinusitis picture with expansile sinus opacification and bony erosions. There is central hyperdensity on CT scan, which appears hyperintense on T1-weighted and hypointense on T2-weighted MR images

Multilevel binomial logistic prediction model for malignant pulmonary nodules based on texture features of CT image

International Nuclear Information System (INIS)

Wang Huan; Guo Xiuhua; Jia Zhongwei; Li Hongkai; Liang Zhigang; Li Kuncheng; He Qian

2010-01-01

Purpose: To introduce multilevel binomial logistic prediction model-based computer-aided diagnostic (CAD) method of small solitary pulmonary nodules (SPNs) diagnosis by combining patient and image characteristics by textural features of CT image. Materials and methods: Describe fourteen gray level co-occurrence matrix textural features obtained from 2171 benign and malignant small solitary pulmonary nodules, which belongs to 185 patients. Multilevel binomial logistic model is applied to gain these initial insights. Results: Five texture features, including Inertia, Entropy, Correlation, Difference-mean, Sum-Entropy, and age of patients own aggregating character on patient-level, which are statistically different (P < 0.05) between benign and malignant small solitary pulmonary nodules. Conclusion: Some gray level co-occurrence matrix textural features are efficiently descriptive features of CT image of small solitary pulmonary nodules, which can profit diagnosis of earlier period lung cancer if combined patient-level characteristics to some extent.

Visualizing Typical Features of Breast Fibroadenomas Using Phase-Contrast CT: An Ex-Vivo Study

Science.gov (United States)

Grandl, Susanne; Willner, Marian; Herzen, Julia; Sztrókay-Gaul, Anikó; Mayr, Doris; Auweter, Sigrid D.; Hipp, Alexander; Birnbacher, Lorenz; Marschner, Mathias; Chabior, Michael; Reiser, Maximilian; Pfeiffer, Franz; Bamberg, Fabian; Hellerhoff, Karin

2014-01-01

Background Fibroadenoma is the most common benign solid breast lesion type and a very common cause for histologic assessment. To justify a conservative therapy, a highly specific discrimination between fibroadenomas and other breast lesions is crucial. Phase-contrast imaging offers improved soft-tissue contrast and differentiability of fine structures combined with the potential of 3-dimensional imaging. In this study we assessed the potential of grating-based phase-contrast CT imaging for visualizing diagnostically relevant features of fibroadenomas. Materials and Methods Grating-based phase-contrast CT was performed on six ex-vivo formalin-fixed breast specimens containing a fibroadenoma and three samples containing benign changes that resemble fibroadenomas using Talbot Lau interferometry and a polychromatic X-ray source. Phase-contrast and simultaneously acquired absorption-based 3D-datasets were manually matched with corresponding histological slices. The visibility of diagnostically valuable features was assessed in comparison with histology as the gold-standard. Results In all cases, matching of grating-based phase-contrast CT images and histology was successfully completed. Grating-based phase-contrast CT showed greatly improved differentiation of fine structures and provided accurate depiction of strands of fibrous tissue within the fibroadenomas as well as of the diagnostically valuable dilated, branched ductuli of the fibroadenomas. A clear demarcation of tumor boundaries in all cases was provided by phase- but not absorption-contrast CT. Conclusions Pending successful translation of the technology to a clinical setting and considerable reduction of the required dose, the data presented here suggest that grating-based phase-contrast CT may be used as a supplementary non-invasive diagnostic tool in breast diagnostics. Phase-contrast CT may thus contribute to the reduction of false positive findings and reduce the recall and core biopsy rate in population

CT findings of hepatoblastoma before and after chemotherapy : correlation with pathologic features

International Nuclear Information System (INIS)

Seo, Joon Beom; Kim, Woo Sun; Kim, In One; Jang, Ja June; Kim, Chong Jai; Ahn, Hyo Seop; Yeon, Kyung Mo

1998-01-01

The purpose of this study was to analyze the CT findings of hepatoblastoma before and after chemotherapy, and to compare them with surgical and pathologic features. Twelve hepatoblastoma patients underwent chemotherapy prior to surgery; in all cases, CT scanning was performed before and after chemotherapy. We reviewed the findings with special attention to changes in tumor volume, the extent and pattern of contrast enhancement, the extent of low-attenuation area in the tumor, the presence of a septum, and calcification or ossification or ossification within the mass before and after chemotherapy. Post-chemotherapy CT findings were compared with operative and pathologic findings. After chemotheapy, the volume of the tumor mass decreased in all patients, and the extent of involved segments decreased in nine (75%), the non-enhancing area within the mass, on the other hand, increased in nine (75 %). On pre-chemotherapy CT, calcifications were detected in seven patients (58%), and on post-chemotherapy CT, in nine (75%); the extent of calcification were detected in seven patients. On the basis of CT findings, viable tumor and necrosis areas could not be distinguished. Massive calcification or osteoid mixed with loose connective tissue was noted in the mesenchymal component of the tumor; the whirling pattern of enhancement within the area of low density seen on CT scanning corresponded to osteoid mixed with loose connective tissue, which contained rich blood vessels. We describe the CT findings of hepatoblastoma both before and after chemotherapy, highlighting the changes which occurred. An understanding of these changes is helpful for the proper management of this condition. (author). 18 refs., 1 tab., 5 figs

Differential CT features of infectious pneumonia versus bronchioloalveolar carcinoma (BAC) mimicking pneumonia

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae Hoon [Yonsei University College of Medicine, Department of Radiology, Seoul (Korea); Yongdong Severance Hospital, Department of Radiology, Seoul (Korea); Kim, Sang Jin; Ryu, Young Hoon; Chung, Soo Yoon; Seo, Jae Seung; Kim, Young Jin; Choi, Byoung Wook [Yonsei University College of Medicine, Department of Radiology, Seoul (Korea); Lee, Sun Hwa [NeoDin Medical Institute, Department of Clinical Pathology, Seoul (Korea); Cho, Sang Ho [Yonsei University College of Medicine, Department of Pathology, Seoul (Korea)

2006-08-15

The purpose of this study was to evaluate retrospectively the differential CT features of bronchioloalveolar carcinoma (BAC) mimicking pneumonia and infectious pneumonia at the lung periphery. CT images were reviewed in 47 patients with focal areas of parenchymal opacification at the lung periphery. We evaluated the presence of ground-glass attenuation, marginal conspicuity of the lesion, CT angiogram sign, air-bronchogram sign, a bubble-like low-attenuation area within the lesion, presence of pleural thickening and retraction associated with the lesion, presence of pleural effusion and extra-pleural fatty hypertrophy, presence of bronchial wall thickening proximal to the lesion, and air-trapping in the normal lung near the lesion. BAC (n=18) depicted the presence of a bubble-like low-attenuation area within the lesion, whereas infectious pneumonia (n=29) represented the pleural thickening associated with the lesion and bronchial wall thickening proximal to the lesion (P<0.05). The other CT findings showed no significant differences (P>0.05). The focal areas of the parenchymal opacification on the CT images may suggest infectious pneumonia rather than BAC when they show bronchial wall thickening proximal to the lesion and pleural thickening associated with the lesion, whereas BAC is characterized as the presence of a bubble-like low attenuation area within the tumor. (orig.)

Automatic extraction of forward stroke volume using dynamic PET/CT

DEFF Research Database (Denmark)

Harms, Hans; Tolbod, Lars Poulsen; Hansson, Nils Henrik Stubkjær

2015-01-01

Background The aim of this study was to develop and validate an automated method for extracting forward stroke volume (FSV) using indicator dilution theory directly from dynamic positron emission tomography (PET) studies for two different tracers and scanners. Methods 35 subjects underwent...... a dynamic 11 C-acetate PET scan on a Siemens Biograph TruePoint-64 PET/CT (scanner I). In addition, 10 subjects underwent both dynamic 15 O-water PET and 11 C-acetate PET scans on a GE Discovery-ST PET/CT (scanner II). The left ventricular (LV)-aortic time-activity curve (TAC) was extracted automatically...... from PET data using cluster analysis. The first-pass peak was isolated by automatic extrapolation of the downslope of the TAC. FSV was calculated as the injected dose divided by the product of heart rate and the area under the curve of the first-pass peak. Gold standard FSV was measured using phase...

Goblet cell carcinoid neoplasm of the appendix: Clinical and CT features

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Lee, K.S., E-mail: kyungmouklee@alum.mit.edu [Department of Radiology Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Tang, L.H., E-mail: tangl@mskc.org [Department of Pathology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Shia, J., E-mail: shiaj@mskcc.org [Department of Pathology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Paty, P.B., E-mail: patyp@mskcc.org [Department of Surgery, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Weiser, M.R., E-mail: weiser1@mskcc.org [Department of Surgery, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Guillem, J.G., E-mail: guillemj@mskcc.org [Department of Surgery, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Temple, L.K., E-mail: temple@mskcc.org [Department of Surgery, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Nash, G.M., E-mail: nashg@mskcc.org [Department of Surgery, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Reidy, D., E-mail: reidyd@mskcc.org [Department of Medicine, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Saltz, L., E-mail: saltzl@mskcc.org [Department of Medicine, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Gollub, M.J., E-mail: gollubm@mskcc.org [Department of Radiology Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States)

2013-01-15

Purpose: To describe the clinical and CT imaging features of goblet cell carcinoid (GCC) neoplasm of the appendix. Methods and materials: A computer search of pathology and radiology records over a 19-year period at our two institutions was performed using the search string “goblet”. In the patients with appendiceal GCC neoplasms who had abdominopelvic CT, imaging findings were categorized, blinded to gross and surgical description, as: “Appendicitis”, “Prominent appendix without peri-appendiceal infiltration”, “Mass” or “Normal appendix”. The CT appearance was correlated with an accepted pathological classification of: low grade GCC, signet ring cell adenocarcinoma ex, and poorly differentiated adenocarcinoma ex GCC group. Results: Twenty-seven patients (age range, 28–80 years; mean age, 52 years; 15 female, 12 male) with pathology-proven appendiceal GCC neoplasm had CT scans that were reviewed. Patients presented with acute appendicitis (n = 12), abdominal pain not typical for appendicitis (n = 14) and incidental finding (n = 1). CT imaging showed 9 Appendicitis, 9 Prominent appendices without peri-appendiceal infiltration, 7 Masses and 2 Normal appendices. Appendicitis (8/9) usually correlated with typical low grade GCC on pathology. In contrast, the majority of Masses and Prominent Appendices without peri-appendiceal infiltration were pathologically confirmed to be signet ring cell adenocarcinoma ex GCC. Poorly differentiated adenocarcinoma ex GCC was seen in only a small minority of patients. Hyperattenuation of the appendiceal neoplasm was seen in a majority of cases. Conclusions: GCC neoplasm of the appendix should be considered in the differential diagnosis in patients with primary appendiceal malignancy. Our cases demonstrated close correlation between our predefined CT pattern and the pathological classification.

Goblet cell carcinoid neoplasm of the appendix: Clinical and CT features

International Nuclear Information System (INIS)

Lee, K.S.; Tang, L.H.; Shia, J.; Paty, P.B.; Weiser, M.R.; Guillem, J.G.; Temple, L.K.; Nash, G.M.; Reidy, D.; Saltz, L.; Gollub, M.J.

2013-01-01

Purpose: To describe the clinical and CT imaging features of goblet cell carcinoid (GCC) neoplasm of the appendix. Methods and materials: A computer search of pathology and radiology records over a 19-year period at our two institutions was performed using the search string “goblet”. In the patients with appendiceal GCC neoplasms who had abdominopelvic CT, imaging findings were categorized, blinded to gross and surgical description, as: “Appendicitis”, “Prominent appendix without peri-appendiceal infiltration”, “Mass” or “Normal appendix”. The CT appearance was correlated with an accepted pathological classification of: low grade GCC, signet ring cell adenocarcinoma ex, and poorly differentiated adenocarcinoma ex GCC group. Results: Twenty-seven patients (age range, 28–80 years; mean age, 52 years; 15 female, 12 male) with pathology-proven appendiceal GCC neoplasm had CT scans that were reviewed. Patients presented with acute appendicitis (n = 12), abdominal pain not typical for appendicitis (n = 14) and incidental finding (n = 1). CT imaging showed 9 Appendicitis, 9 Prominent appendices without peri-appendiceal infiltration, 7 Masses and 2 Normal appendices. Appendicitis (8/9) usually correlated with typical low grade GCC on pathology. In contrast, the majority of Masses and Prominent Appendices without peri-appendiceal infiltration were pathologically confirmed to be signet ring cell adenocarcinoma ex GCC. Poorly differentiated adenocarcinoma ex GCC was seen in only a small minority of patients. Hyperattenuation of the appendiceal neoplasm was seen in a majority of cases. Conclusions: GCC neoplasm of the appendix should be considered in the differential diagnosis in patients with primary appendiceal malignancy. Our cases demonstrated close correlation between our predefined CT pattern and the pathological classification

Papillary thyroid carcinoma: comparison between CT features and pathologic findings

International Nuclear Information System (INIS)

Tan Hongna; Gu Yajia; Peng Weijun; Yang Wentao; Huang Dan

2009-01-01

Objective: To evaluate the relationship between the CT imaging features and pathologic findings of papillary thyroid carcinoma (PTC) and papillary thyroid microcarcinoma (PTMC), as well as the CT appearances of Non-papillary thyroid carcinoma(N-PTC). Methods: CT features of 229 PTC, 42 PTMC and 36 N-PTC patients with 264, 57 and 41 lesions respectively were analyzed retrospectively, and comparison was made with the pathologic findings. All data were analyzed by X 2 test. Results: (1) Of PTC lesions, 25.4% (67/264)of the lesions and 2.9% (24/828) of metastatic lymph nodes showed cystic changes. Cyst formation with intracystic high density papillary-like nodules were found in 31.3% (21/67)of the PTC lesions and 37.5% (9/24) of metastatic lymph nodes. The histologic appearances of these tumors demonstrated fibrous tissue forming the wall of cyst, and papillary-like tumor tissue. (2) 75.2% (112/149) of PTC and 33.3% (5/15) of PTMC showed multiple small granular and fine calcifications, and there was statiscally significant difference between the two (P 0.05). However, the degree of enhancement in PTC lesions were less than that of N-PTC, 36.6% (94/257) of PTC and 54.1% (20/37)of N-PTC lesions showed significant enhancement, and there was statistically significant difference (P<0.05). 75.1% of PTC (172/229) and 52.8% of (19/36)N-PTC had cervical lymph node metastases, with a propensity fbr PTC to have more VI region metastatic lymph nodes, 80.8% (139/172)vs 57.9% (11/19), which was statistically significant (both P<0.05). (4)Distant metastases to bone or lung were rare, but N-PTC (5/36) were more likely to produce distant metastases than PTC (5/229), and there was statistically significant difference (P<0.01). Conclusion Multiple, small granular and fine calcifications were found more frequently in PTC than PTMC. Compared with N-PTC, the papillary-like mural nodules of PTC showed less enhancement on post-contrast CT and cervical lymph node metastases were more

Diagnostic performance and useful findings of ultrasound re-evaluation for patients with equivocal CT features of acute appendicitis.

Science.gov (United States)

Kim, Mi Sung; Kwon, Heon-Ju; Kang, Kyung A; Do, In-Gu; Park, Hee-Jin; Kim, Eun Young; Hong, Hyun Pyo; Choi, Yoon Jung; Kim, Young Hwan

2018-02-01

To evaluate the diagnostic performance of ultrasound and to determine which ultrasound findings are useful to differentiate appendicitis from non-appendicitis in patients who underwent ultrasound re-evaluation owing to equivocal CT features of acute appendicitis. 62 patients who underwent CT examinations for suspected appendicitis followed by ultrasound re-evaluation owing to equivocal CT findings were included. Equivocal CT findings were considered based on the presence of only one or two findings among the CT criteria, and ultrasound re-evaluation was done based on a predefined structured report form. The diagnostic performance of ultrasound and independent variables to discriminate appendicitis from non-appendicitis were assessed. There were 27 patients in the appendicitis group. The overall diagnostic performance of ultrasound re-evaluation was sensitivity of 96.3%, specificity of 91.2% and accuracy of 91.9%. In terms of the performance of individual ultrasound findings, probe-induced tenderness showed the highest accuracy (86.7%) with sensitivity of 74% and specificity of 97%, followed by non-compressibility (accuracy 71.7%, sensitivity 85.2% and specificity 60.6%). The independent ultrasound findings for discriminating appendicitis were non-compressibility (p = 0.002) and increased flow on the appendiceal wall (p = 0.001). Ultrasound re-evaluation can be used to improve diagnostic accuracy in cases with equivocal CT features for diagnosing appendicitis. The presence of non-compressibility and increased vascular flow on the appendix wall are useful ultrasound findings to discriminate appendicitis from non-appendicitis. Advances in knowledge: Ultrasound re-evaluation is useful to discriminate appendicitis from non-appendicitis when CT features are inconclusive.

Development of a nomogram combining clinical staging with 18F-FDG PET/CT image features in non-small-cell lung cancer stage I-III

International Nuclear Information System (INIS)

Desseroit, Marie-Charlotte; Visvikis, Dimitris; Majdoub, Mohamed; Hatt, Mathieu; Tixier, Florent; Perdrisot, Remy; Cheze Le Rest, Catherine; Guillevin, Remy

2016-01-01

Our goal was to develop a nomogram by exploiting intratumour heterogeneity on CT and PET images from routine 18 F-FDG PET/CT acquisitions to identify patients with the poorest prognosis. This retrospective study included 116 patients with NSCLC stage I, II or III and with staging 18 F-FDG PET/CT imaging. Primary tumour volumes were delineated using the FLAB algorithm and 3D Slicer trademark on PET and CT images, respectively. PET and CT heterogeneities were quantified using texture analysis. The reproducibility of the CT features was assessed on a separate test-retest dataset. The stratification power of the PET/CT features was evaluated using the Kaplan-Meier method and the log-rank test. The best standard metric (functional volume) was combined with the least redundant and most prognostic PET/CT heterogeneity features to build the nomogram. PET entropy and CT zone percentage had the highest complementary values with clinical stage and functional volume. The nomogram improved stratification amongst patients with stage II and III disease, allowing identification of patients with the poorest prognosis (clinical stage III, large tumour volume, high PET heterogeneity and low CT heterogeneity). Intratumour heterogeneity quantified using textural features on both CT and PET images from routine staging 18 F-FDG PET/CT acquisitions can be used to create a nomogram with higher stratification power than staging alone. (orig.)

Diagnostic value of CT features of the gallbladder in the prediction of gallstone pancreatitis

Energy Technology Data Exchange (ETDEWEB)

Yie, Miyeon [Department of Radiology, Hallym University College of Medicine, 896 Pyungchon-dong, Dongan-gu, Anyang-city, Kyungki-do 431-070 (Korea, Republic of); Jang, Kyung Mi, E-mail: jkm7290@empal.com [Department of Radiology, Hallym University College of Medicine, 896 Pyungchon-dong, Dongan-gu, Anyang-city, Kyungki-do 431-070 (Korea, Republic of); Department of Radiology and Center for Imaging Science, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of); Kim, Min Jeong; Lee, Yul [Department of Radiology, Hallym University College of Medicine, 896 Pyungchon-dong, Dongan-gu, Anyang-city, Kyungki-do 431-070 (Korea, Republic of); Choi, Dongil [Department of Radiology and Center for Imaging Science, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of)

2011-11-15

Purpose: The aim of this retrospective study was to evaluate the diagnostic value of CT features of the gallbladder in the prediction of gallstone pancreatitis. Materials and methods: Eighty-six patients who underwent a diagnostic computed tomography (CT) scan for acute pancreatitis were included. The readers assessed the presence of pericholecystic increased attenuation of the liver parenchyma, enhancement of gallbladder (GB) and common bile duct (CBD) wall, pericholecystic fat strands, GB wall thickening, stone in the GB or CBD, and focal or diffuse manifestations of pancreatitis on abdominal CT scans. In addition, the maximal transverse luminal diameters of the GB and CBD were measured. Results: The presence of pericholecystic increased attenuation of the liver parenchyma, GB wall enhancement and thickening, pericholecystic fat strands, stone in the GB or CBD, and diffuse manifestations of pancreatitis achieved statistical significance for differentiation of gallstone induced pancreatitis from non-biliary pancreatitis (p < 0.05). The mean values of maximal transverse luminal diameter of GB and CBD were significantly higher in gallstone induced pancreatitis group (39.67 {+-} 7.26 mm, 10.20 {+-} 4.13 mm) than non-biliary pancreatitis group (27.01 {+-} 6.14 mm, 3.85 {+-} 2.51 mm, p < 0.0001). Conclusion: Gallbladder features of CT in patients with pancreatitis could be the valuable clues for the diagnosis of gallstone induced pancreatitis.

Automated measurement of CT noise in patient images with a novel structure coherence feature

International Nuclear Information System (INIS)

Chun, Minsoo; Kim, Jong Hyo; Choi, Young Hun

2015-01-01

While the assessment of CT noise constitutes an important task for the optimization of scan protocols in clinical routine, the majority of noise measurements in practice still rely on manual operation, hence limiting their efficiency and reliability. This study presents an algorithm for the automated measurement of CT noise in patient images with a novel structure coherence feature. The proposed algorithm consists of a four-step procedure including subcutaneous fat tissue selection, the calculation of structure coherence feature, the determination of homogeneous ROIs, and the estimation of the average noise level. In an evaluation with 94 CT scans (16 517 images) of pediatric and adult patients along with the participation of two radiologists, ROIs were placed on a homogeneous fat region at 99.46% accuracy, and the agreement of the automated noise measurements with the radiologists’ reference noise measurements (PCC  =  0.86) was substantially higher than the within and between-rater agreements of noise measurements (PCC within   =  0.75, PCC between   =  0.70). In addition, the absolute noise level measurements matched closely the theoretical noise levels generated by a reduced-dose simulation technique. Our proposed algorithm has the potential to be used for examining the appropriateness of radiation dose and the image quality of CT protocols for research purposes as well as clinical routine. (paper)

CT features of focal organizing pneumonia: An analysis of consecutive histopathologically confirmed 45 cases

Energy Technology Data Exchange (ETDEWEB)

Zhao, Feng [Department of Radiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, 310016 (China); Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR (China); Yan, Sen-Xiang [Department of Radiation Oncology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003 (China); Wang, Gao-Feng [Department of Radiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, 310016 (China); Wang, Jin [Department of Pathology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, 310016 (China); Lu, Pu-Xuan [Department of Radiology, Shenzhen Third People' s Hospital, Guangdong Medical College, Shenzhen, 518020 (China); Chen, Bin [Department of Radiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, 310016 (China); Yuan, Jing [Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR (China); Zhang, Shi-Zheng, E-mail: shizhengzhang@hotmail.com [Department of Radiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, 310016 (China); Wang, Yi-Xiang J., E-mail: yixiang_wang@cuhk.edu.hk [Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR (China); Department of Radiology, Shenzhen Third People' s Hospital, Guangdong Medical College, Shenzhen, 518020 (China)

2014-01-15

Objective: To study the CT characteristics of solitary focal organizing pneumonia (FOP). Materials and methods: Chest CT of consecutive 45 patients (34 males and 11 females, median age: 56 years) with confirmed FOP were analyzed. The CT features between large FOP (>3 cm, n = 27) and small FOP (≤3 cm, n = 18) were compared. Results: FOP lesions predominately located in peripheral lungs (86.7%), with the right lower lobe being most common lobe (44.4%). No lesion mainly located in the inner 1/3 of lungs. All large lesions were polygon in shape and had an irregular margin, while small lesions were more likely to be round or oval with an irregular or smooth border. Air bronchogram or small bubble-like lucency was present in majority of the lesions. 42.2% of lesions had incompact internal structure with inhomogeneous density besides air component. Most lesions were associated with a contraction or convergence of surrounding vessels; while no pulmonary vessel was interrupted abruptly by a small FOP lesion. Majority of large lesions had broad contact with the pleura, while only one patient had mild pleural effusion. Mild mediastinal lymph nodes enlargement was present in about 1/5 of the patients. Conclusion: Compared with the known CT features of lung cancer, our results suggest differential diagnosis can often be made for large FOP, while small FOP may resemble lung cancer.

MR, CT, and myelographic features of epidural lipomatosis

International Nuclear Information System (INIS)

Quint, D.J.; Boulos, R.S.; Patel, S.C.; Sanders, W.P.; Tiel, R.L.; Washington, J.M.

1987-01-01

Central deposition of fat is a well-known clinical feature of chronically elevated corticosteroid levels. Rarely described is increased extradural fat causing compression of the spinal cord and neurologic deficits. Twelve previously reported and five new cases of epidural lipomatosis are presented. Representative examples of the common myelographic and CT findings in this disorder are shown. In addition, previously undescribed examples of epidural lipomatosis demonstrating (1) the MR findings, (2) no associated myelographic block, (3) lipomatosis in both the thoracic and lumbar regions, and (4) a case in a nonobese patient without known steroid use are presented. The importance of considering this entity in the appropriate clinical setting (chronic exogenous steroid use) even with a normal myelogram is stressed

Evaluation of detectability of right inferior phrenic artery root in dynamic CT

Energy Technology Data Exchange (ETDEWEB)

Sato, Osamu [Akashi Municipal Hospital, Hyogo (Japan); Kizu, Osamu; Shimizu, Toshihisa; Takahashi, Takeshi; Ohno, Koji; Ohmura, Makoto; Maeda, Tomoho

1995-05-01

We evaluated the detectability of the root of the right inferior phrenic artery in dynamic CT over the entire liver as used for the diagnosis of hepatocellular carcinoma. The results showed no detection in three cases, poor detection in seven, detection in 12 and good detection in eight. The right inferior phrenic artery could be detected in many cases. Identification was easier in cases with direct branching from the aorta. It can be concluded that for angiographic examination, dynamic CT over the entire liver is useful for catheterization to the right inferior phrenic artery. (author).

Evaluation of detectability of right inferior phrenic artery root in dynamic CT

International Nuclear Information System (INIS)

Sato, Osamu; Kizu, Osamu; Shimizu, Toshihisa; Takahashi, Takeshi; Ohno, Koji; Ohmura, Makoto; Maeda, Tomoho.

1995-01-01

We evaluated the detectability of the root of the right inferior phrenic artery in dynamic CT over the entire liver as used for the diagnosis of hepatocellular carcinoma. The results showed no detection in three cases, poor detection in seven, detection in 12 and good detection in eight. The right inferior phrenic artery could be detected in many cases. Identification was easier in cases with direct branching from the aorta. It can be concluded that for angiographic examination, dynamic CT over the entire liver is useful for catheterization to the right inferior phrenic artery. (author)

Pulmonary aspergillosis in immunocompetent patients without air-meniscus sign and underlying lung disease: CT findings and histopathologic features

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Yoon, Soon Ho; Park, Chang Min; Goo, Jin Mo; Lee, Hyun Ju (Dept. of Radiology and Institute of Radiation Medicine, Seoul National Univ. Hospital, Seoul (Korea, Republic of)), email: rosaceci@radiol.snu.ac.kr

2011-09-15

Background: Pulmonary aspergillosis in immunocompetent patients has been described as a saprophytic infection with pre-existing lung lesions showing an air-meniscus sign on chest radiograph or CT scans. There have been rare articles dealing with pulmonary aspergillosis in immunocompetent patients without pre-existing lung lesions. Purpose: To evaluate the CT findings of pulmonary aspergillosis in immunocompetent patients without air-meniscus and underlying lung disease and to correlate the CT findings and pathologic features of pulmonary aspergillosis in these patients. Material and Methods: A total of seven surgically proven pulmonary aspergillosis found in immunocompetent patients without an air-meniscus and underlying lung disease (M:F = 1:6; mean age 63.4 years) were included. On CT, the lesion shape, margin, type, location, diameter, presence of satellite nodules, presence of CT halo sign or hypodense sign, and interval growth were evaluated. Histopathologic features of each lesion were classified as one of the following; primary aspergilloma, chronic necrotizing pulmonary aspergillosis, or invasive pulmonary aspergillosis. Correlation between CT findings and pathological features was performed. Results: All lesions presented as a nodule or mass unable to differentiate from malignancy. Most lesions had well-defined margins (n = 4), appeared as solid lesions (n = 7), and were located in the upper lobe (n = 5). Mean diameter of lesions was 2.3 cm. Satellite nodules (n = 2), CT halo sign (n = 1), and hypodense sign (n = 4) were found. Only one lesion increased in size during follow-up. Lesions were pathologically classified as primary aspergilloma (n = 3) and chronic necrotizing pulmonary aspergillosis (n = 4). The hypodense sign on CT was pathologically proved as dense fungal hyphae filled in bronchus and CT halo sign as parenchymal hemorrhage. Conclusion: Pulmonary aspergillosis predominantly presented as a nodule or mass mimicking malignancy in the upper lobes

Pulmonary aspergillosis in immunocompetent patients without air-meniscus sign and underlying lung disease: CT findings and histopathologic features

International Nuclear Information System (INIS)

Yoon, Soon Ho; Park, Chang Min; Goo, Jin Mo; Lee, Hyun Ju

2011-01-01

Background: Pulmonary aspergillosis in immunocompetent patients has been described as a saprophytic infection with pre-existing lung lesions showing an air-meniscus sign on chest radiograph or CT scans. There have been rare articles dealing with pulmonary aspergillosis in immunocompetent patients without pre-existing lung lesions. Purpose: To evaluate the CT findings of pulmonary aspergillosis in immunocompetent patients without air-meniscus and underlying lung disease and to correlate the CT findings and pathologic features of pulmonary aspergillosis in these patients. Material and Methods: A total of seven surgically proven pulmonary aspergillosis found in immunocompetent patients without an air-meniscus and underlying lung disease (M:F = 1:6; mean age 63.4 years) were included. On CT, the lesion shape, margin, type, location, diameter, presence of satellite nodules, presence of CT halo sign or hypodense sign, and interval growth were evaluated. Histopathologic features of each lesion were classified as one of the following; primary aspergilloma, chronic necrotizing pulmonary aspergillosis, or invasive pulmonary aspergillosis. Correlation between CT findings and pathological features was performed. Results: All lesions presented as a nodule or mass unable to differentiate from malignancy. Most lesions had well-defined margins (n = 4), appeared as solid lesions (n = 7), and were located in the upper lobe (n = 5). Mean diameter of lesions was 2.3 cm. Satellite nodules (n = 2), CT halo sign (n = 1), and hypodense sign (n = 4) were found. Only one lesion increased in size during follow-up. Lesions were pathologically classified as primary aspergilloma (n = 3) and chronic necrotizing pulmonary aspergillosis (n = 4). The hypodense sign on CT was pathologically proved as dense fungal hyphae filled in bronchus and CT halo sign as parenchymal hemorrhage. Conclusion: Pulmonary aspergillosis predominantly presented as a nodule or mass mimicking malignancy in the upper lobes

Focal Amyloidosis of the Orbit Presenting as a Mass: MRI and CT Features

International Nuclear Information System (INIS)

Yerli, Hasan; Aydin, Erdinc; Avci, Suat; Haberal, Nihan; Oto, Sibel

2011-01-01

Focal orbital amyloidosis is a rare entity and little is known about its magnetic resonance imaging (MRI) features. In this case report, imaging features of a case of focal orbital amyloidosis presenting as a mass have been documented together with its histopathological findings. On MRI, a well-defined mass was seen as isointense with rectus muscle on T1-weighted images and heterogeneously hypointense on T2-weighted images. Punctuate calcifications were observed on the computerized tomography (CT) examination

Pseudomembranous aspergillus bronchitis in a double-lung transplanted patient: unusual radiographic and CT features

International Nuclear Information System (INIS)

Ducreux, D.; Chevallier, P.; Raffaelli, C.; Padovani, B.; Perrin, C.; Jourdan, J.; Hofman, P.

2000-01-01

Pseudomembranous aspergillus bronchitis is considered as an early form of invasive pulmonary aspergillosis, a well-known airway infection in immunocompromised patients. Radiologic features concerning invasive aspergillosis of the airways have been reported. However, we describe here an unusual feature of invasive aspergillus bronchitis, never reported to date, observed in a double-lung transplanted patient. Chest radiograph and CT revealed significant peribronchial thickening without any parenchymal involvement. (orig.)

CT imaging features of anaplastic thyroid carcinoma

International Nuclear Information System (INIS)

Shi Zhenshan; You Ruixiong; Cao Dairong; Li Yueming; Zhuang Qian

2013-01-01

Objective: To investigate the CT characteristics of anaplastic thyroid carcinoma and evaluate the diagnostic value of CT in this disease. Methods: The CT findings of 10 patients with pathologically proved anaplastic thyroid carcinoma were retrospectively reviewed. The patients included 7 females and 3 males. Their age ranged from 25.0 to 78 years with median of 61 years. Multi-slices plain and post contrast CT scans were performed in all patients. Results: Unilateral thyroid was involved in 6 patients. Unilateral thyroid and thyroid isthmus were both involved in 2 patients due to big size. Bilateral thyroid were involved in 2 patients. The maximum diameter of anaplastic thyroid carcinoma ranged from 2.9-12.8 cm with mean of (4.5 ± 1.4) cm. All lesions demonstrated unclear margins and envelope invasion. The densities of all lesions were heterogeneous and obvious necrosis areas were noted on precontrast images. Seven lesions showed varied calcifications, and coarse granular calcifications were found in 5 lesions among them. All lesions showed remarkable heterogenous enhancement on post-contrast CT. The CT value of solid portion of the tumor increased 40 HU after contrast media administration. The ratios of CT value which comparing of the tumor with contralateral sternocleidomastoid muscle were 0.69-0.82 (0.76 ± 0.18) and 1.25-1.41 (1.33 ± 0.28) on pre and post CT, respectively. Enlarged cervical lymph nodes were found in 6 cases (60.0%). It showed obvious homogeneous enhancement or irregular ring-like enhancement on post-contrast images and dot calcifications were seen in 1 case. Conclusions: Relative larger single thyroid masses with coarse granular calcifications, necrosis,envelope invasion, remarkable heterogeneous enhancing and enlarged lymph nodes on CT are suggestive of anaplastic thyroid carcinoma. (authors)

Automatic Classification of Normal and Cancer Lung CT Images Using Multiscale AM-FM Features

Directory of Open Access Journals (Sweden)

Eman Magdy

2015-01-01

Full Text Available Computer-aided diagnostic (CAD systems provide fast and reliable diagnosis for medical images. In this paper, CAD system is proposed to analyze and automatically segment the lungs and classify each lung into normal or cancer. Using 70 different patients’ lung CT dataset, Wiener filtering on the original CT images is applied firstly as a preprocessing step. Secondly, we combine histogram analysis with thresholding and morphological operations to segment the lung regions and extract each lung separately. Amplitude-Modulation Frequency-Modulation (AM-FM method thirdly, has been used to extract features for ROIs. Then, the significant AM-FM features have been selected using Partial Least Squares Regression (PLSR for classification step. Finally, K-nearest neighbour (KNN, support vector machine (SVM, naïve Bayes, and linear classifiers have been used with the selected AM-FM features. The performance of each classifier in terms of accuracy, sensitivity, and specificity is evaluated. The results indicate that our proposed CAD system succeeded to differentiate between normal and cancer lungs and achieved 95% accuracy in case of the linear classifier.

Investigating the role of SPECT/CT in dynamic sentinel lymph node biopsy for penile cancers

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Saad, Ziauddin Zia; Bomanji, Jamshed [University College Hospitals London, Department of Nuclear Medicine, London (United Kingdom); UCLH NHS Foundation Trust, Institute of Nuclear Medicine, 5th Floor, London (United Kingdom); Omorphos, Savvas; Malone, Peter; Nigam, Raj; Muneer, Asif [University College Hospitals London, Department of Urology, London (United Kingdom); Michopoulou, Sofia; Gacinovic, Svetislav [University College Hospitals London, Department of Nuclear Medicine, London (United Kingdom)

2017-07-15

Currently, most centres use 2-D planar lymphoscintigraphy when performing dynamic sentinel lymph node biopsy in penile cancer patients with clinically impalpable inguinal nodes. This study aimed to investigate the role of SPECT/CT following 2-D planar lymphoscintigraphy (dynamic and static) in the detection and localization of sentinel lymph nodes in the groin. A qualitative (visual) review was performed on planar followed by SPECT/CT lymphoscintigraphy in 115 consecutive patients (age 28-86 years) who underwent injection of {sup 99m}Tc-nanocolloid followed by immediate acquisition of dynamic (20 min) and early static scans (5 min) initially and further delayed static (5 min) images at 120 min followed by SPECT/CT imaging. The lymph nodes detected in each groin on planar lymphoscintigraphy and SPECT/CT were compared. A total of 440 and 467 nodes were identified on planar scintigraphy and SPECT/CT, respectively. Overall, SPECT/CT confirmed the findings of planar imaging in 28/115 cases (24%). In the remaining 87 cases (76%), gross discrepancies were observed between planar and SPECT/CT images. SPECT/CT identified 17 instances of skin contamination (16 patients, 13%) and 36 instances of in-transit lymphatic tract activity (24 patients, 20%) that had been interpreted as tracer-avid lymph nodes on planar imaging. In addition, SPECT/CT identified 53 tracer-avid nodes in 48 patients (42%) that were not visualized on planar imaging and led to reclassification of the drainage basins (pelvic/inguinal) of 27 tracer-avid nodes. The addition of SPECT/CT improved the rate of detection of true tracer-avid lymph nodes and delineated their precise (3-D) anatomic localization in drainage basins. (orig.)

Atypical adenomatous hyperplasia of the lung: correlation between high-resolution CT findings and histopathologic features

International Nuclear Information System (INIS)

Kawakami, S.; Takashima, S.; Li, F.; Yang, Z.G.; Maruyama, Y.; Hasegawa, M.; Wang, J.C.; Sone, S.; Honda, T.

2001-01-01

We describe herein the CT features of atypical adenomatous hyperplasia (AAH) of the lung and its histopathological characteristics. Among 17,919 individuals screened for lung cancer by CT scanning, ten AAH nodules were detected in nine asymptomatic subjects. On high-resolution CT, the lesions measured from 6 x 6 mm to 15 x 17 mm and their CT number ranged from -500 to -760 HU. The AAHs appeared as round nodules with smooth and distinct borders and showed a ground-glass opacity. Plain chest radiographs failed to identify all lesions. Histopathologically, AAH lesions showed atypical epithelial cell proliferation along slightly thickened alveolar septa. Whereas it is often easy to differentiate these nodules from inflammatory and benign lung lesions, histopathological examination remains at present the only method to differentiate AAH from lung cancers. (orig.)

Atypical adenomatous hyperplasia of the lung: correlation between high-resolution CT findings and histopathologic features

Energy Technology Data Exchange (ETDEWEB)

Kawakami, S.; Takashima, S.; Li, F.; Yang, Z.G.; Maruyama, Y.; Hasegawa, M.; Wang, J.C. [Dept. of Radiology, Shinshu University School of Medicine, Matsumoto (Japan); Sone, S. [Dept. of Radiology, Shinshu University School of Medicine, Matsumoto (Japan); Azumi General Hospital, Ikeda, Nagano (Japan); Honda, T. [Dept. of Laboratory Medicine, Shinshu University School of Medicine, Matsumoto (Japan)

2001-05-01

We describe herein the CT features of atypical adenomatous hyperplasia (AAH) of the lung and its histopathological characteristics. Among 17,919 individuals screened for lung cancer by CT scanning, ten AAH nodules were detected in nine asymptomatic subjects. On high-resolution CT, the lesions measured from 6 x 6 mm to 15 x 17 mm and their CT number ranged from -500 to -760 HU. The AAHs appeared as round nodules with smooth and distinct borders and showed a ground-glass opacity. Plain chest radiographs failed to identify all lesions. Histopathologically, AAH lesions showed atypical epithelial cell proliferation along slightly thickened alveolar septa. Whereas it is often easy to differentiate these nodules from inflammatory and benign lung lesions, histopathological examination remains at present the only method to differentiate AAH from lung cancers. (orig.)

Parametric features of image textures in 18F-FDG PET/CT evaluation of lung nodules

International Nuclear Information System (INIS)

Wang Changmei; Guan Yihui; Zhang Wenqiang; Zuo Chuantao; Hua Fengchun

2013-01-01

Objective: To evaluate the parametric features of image textures on 18 F-FDG PET/CT for the differentiation between malignant and benign pulmonary nodules and compare the diagnostic performance of these parameters with SUV max . Methods: 18 F-FDG PET/CT images of 170 patients (102 males, 68 females, age range: 29-81 (mean 59) years) with pulmonary nodules were retrospectively evaluated. Eighty-nine pulmonary nodules (230 slices) were malignant and 81 (193 slices) were benign. The pulmonary nodules were contoured on CT images and mapped to the co-registered PET images. Thirteen parameters of textural features were extracted and SUV max was measured. Logistic regression analysis was used to identify the significant texture parameters and create a regression model. The efficacy of the textural features and SUV max to distinguish between malignant and benign pulmonary nodules was evaluated by ROC curve analysis. The textural features of squamous cell carcinoma and adenocarcinoma were compared via the Mann-Whitney u test. The sensitivity and specificity of the textural features and SUV max for the differential diagnosis were compared with χ 2 test. Results: Logistic regression model identified 4 textural features (skewness (β=1.7058), kurtosis (β=-1.0989), angular second moment (ASM, 3=-4.4140) and strength (β=0.5626); all P<0.05) to have significant correlation with the malignancy of lung nodules. The AUC of ROC curve was 0.775 (95% CI 0.732-0.819; P<0.001) with the sensitivity of 89.6% (206/230) and specificity of 50.8% (98/193). ASM and strength had statistically significant differences between squamous cell carcinoma and adenocarcinoma [ASM: 0.0303 (95% CI 0.0392-0.0724) vs 0.0594 (95% CI 0.0721-0.0947); strength: 2.4714 (95% CI 2.4632-4.1050) vs 1.5945 (95% CI 1.9003-2.4652); u=3082.0 and 3115.0, both P<0.01]. The AUC of SUV max -based diagnosis was 0.757 (95% CI 0.711-0.802; P<0.001) with the sensitivity of 80.9% (186/230) and specificity of 50.3% (97/193) at

Adenosine-stress dynamic real-time myocardial perfusion CT and adenosine-stress first-pass dual-energy myocardial perfusion CT for the assessment of acute chest pain: Initial results

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Weininger, Markus [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Department of Medicine, Division of Cardiology, Medical University of South Carolina, Charleston, SC (United States); Ramachandra, Ashok [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Fink, Christian [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany); Rowe, Garrett W.; Costello, Philip [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Henzler, Thomas [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany)

2012-12-15

Purpose: Recent innovations in CT enable the evolution from mere morphologic imaging to dynamic and functional testing. We describe our initial experience performing myocardial stress perfusion CT in a clinical population with acute chest pain. Methods and materials: Myocardial stress perfusion CT was performed on twenty consecutive patients (15 men, 5 women; mean age 65 ± 8 years) who presented with acute chest pain and were clinically referred for stress/rest SPECT and cardiac MRI. Prior to CT each patient was randomly assigned either to Group A or to Group B in a consecutive order (10 patients per group). Group A underwent adenosine-stress dynamic real-time myocardial perfusion CT using a novel “shuttle” mode on a 2nd generation dual-source CT. Group B underwent adenosine-stress first-pass dual-energy myocardial perfusion CT using the same CT scanner in dual-energy mode. Two experienced observers visually analyzed all CT perfusion studies. CT findings were compared with MRI and SPECT. Results: In Group A 149/170 myocardial segments (88%) could be evaluated. Real-time perfusion CT (versus SPECT) had 86% (84%) sensitivity, 98% (92%) specificity, 94% (88%) positive predictive value, and 96% (92%) negative predictive value in comparison with perfusion MRI for the detection of myocardial perfusion defects. In Group B all myocardial segments were available for analysis. Compared with MRI, dual-energy myocardial perfusion CT (versus SPECT) had 93% (94%) sensitivity, 99% (98%) specificity, 92% (88%) positive predictive value, and 96% (94%) negative predictive value for detecting hypoperfused myocardial segments. Conclusion: Our results suggest the clinical feasibility of myocardial perfusion CT imaging in patients with acute chest pain. Compared to MRI and SPECT both, dynamic real-time perfusion CT and first-pass dual-energy perfusion CT showed good agreement for the detection of myocardial perfusion defects.

Adenosine-stress dynamic real-time myocardial perfusion CT and adenosine-stress first-pass dual-energy myocardial perfusion CT for the assessment of acute chest pain: Initial results

International Nuclear Information System (INIS)

Weininger, Markus; Schoepf, U. Joseph; Ramachandra, Ashok; Fink, Christian; Rowe, Garrett W.; Costello, Philip; Henzler, Thomas

2012-01-01

Purpose: Recent innovations in CT enable the evolution from mere morphologic imaging to dynamic and functional testing. We describe our initial experience performing myocardial stress perfusion CT in a clinical population with acute chest pain. Methods and materials: Myocardial stress perfusion CT was performed on twenty consecutive patients (15 men, 5 women; mean age 65 ± 8 years) who presented with acute chest pain and were clinically referred for stress/rest SPECT and cardiac MRI. Prior to CT each patient was randomly assigned either to Group A or to Group B in a consecutive order (10 patients per group). Group A underwent adenosine-stress dynamic real-time myocardial perfusion CT using a novel “shuttle” mode on a 2nd generation dual-source CT. Group B underwent adenosine-stress first-pass dual-energy myocardial perfusion CT using the same CT scanner in dual-energy mode. Two experienced observers visually analyzed all CT perfusion studies. CT findings were compared with MRI and SPECT. Results: In Group A 149/170 myocardial segments (88%) could be evaluated. Real-time perfusion CT (versus SPECT) had 86% (84%) sensitivity, 98% (92%) specificity, 94% (88%) positive predictive value, and 96% (92%) negative predictive value in comparison with perfusion MRI for the detection of myocardial perfusion defects. In Group B all myocardial segments were available for analysis. Compared with MRI, dual-energy myocardial perfusion CT (versus SPECT) had 93% (94%) sensitivity, 99% (98%) specificity, 92% (88%) positive predictive value, and 96% (94%) negative predictive value for detecting hypoperfused myocardial segments. Conclusion: Our results suggest the clinical feasibility of myocardial perfusion CT imaging in patients with acute chest pain. Compared to MRI and SPECT both, dynamic real-time perfusion CT and first-pass dual-energy perfusion CT showed good agreement for the detection of myocardial perfusion defects.

Benign pulmonary nodule. Morphological features and contrast enhancement evaluated with contiguous thin-section CT

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Matsuo, Hisayasu; Murata, Kiyoshi; Takahashi, Masashi; Morita, Rikushi [Shiga Univ. of Medical Science, Otsu (Japan)

1998-10-01

The morphological changes in 54 benign lung nodules, including 8 histologically proven nodules of tuberculoma, 10 of focal organizing pneumonia (FOP), 1 of lung abscess and 35 other benign nodules, were evaluated with contiguous thin-section (3 mm) CT. In addition, incremental dynamic studies were carried out in 25 of these nodules. The three-dimensional shapes of the nodules were found to be quite varied and were classified into four types: round mass (n=18), polygonal mass with concave or straight margins (n=20), oval or band-like mass extending along the bronchovascular bundle (n=7), and oval mass attached to the pleura with broad contact (n=9). Forty-two (78%) of the 54 nodules were located along the bronchovascular bundle. The maximum increments in CT values over 20 HU were observed after contrast enhancement in 18 (72%) of the 25 benign nodules, among which all tuberculomas showed little or no contrast enhancement. The number of small vessels quantified microscopically in the center of the nodules were minimal in tuberculomas with little enhancement and plentiful in lesions of FOP and abscess which showed marked enhancement. Our results suggest that the differentiation between benign and malignant pulmonary nodules is not possible simply on the basis of the degree of contrast enhancement. Therefore, morphological features and the anatomical relation to the bronchovascular bundles should also be taken into consideration in the diagnosis of pulmonary nodules. (author)

Benign pulmonary nodule. Morphological features and contrast enhancement evaluated with contiguous thin-section CT

International Nuclear Information System (INIS)

Matsuo, Hisayasu; Murata, Kiyoshi; Takahashi, Masashi; Morita, Rikushi

1998-01-01

The morphological changes in 54 benign lung nodules, including 8 histologically proven nodules of tuberculoma, 10 of focal organizing pneumonia (FOP), 1 of lung abscess and 35 other benign nodules, were evaluated with contiguous thin-section (3 mm) CT. In addition, incremental dynamic studies were carried out in 25 of these nodules. The three-dimensional shapes of the nodules were found to be quite varied and were classified into four types: round mass (n=18), polygonal mass with concave or straight margins (n=20), oval or band-like mass extending along the bronchovascular bundle (n=7), and oval mass attached to the pleura with broad contact (n=9). Forty-two (78%) of the 54 nodules were located along the bronchovascular bundle. The maximum increments in CT values over 20 HU were observed after contrast enhancement in 18 (72%) of the 25 benign nodules, among which all tuberculomas showed little or no contrast enhancement. The number of small vessels quantified microscopically in the center of the nodules were minimal in tuberculomas with little enhancement and plentiful in lesions of FOP and abscess which showed marked enhancement. Our results suggest that the differentiation between benign and malignant pulmonary nodules is not possible simply on the basis of the degree of contrast enhancement. Therefore, morphological features and the anatomical relation to the bronchovascular bundles should also be taken into consideration in the diagnosis of pulmonary nodules. (author)

Differential CT features of infectious pneumonia versus bronchioloalveolar carcinoma (BAC) mimicking pneumonia

International Nuclear Information System (INIS)

Kim, Tae Hoon; Kim, Sang Jin; Ryu, Young Hoon; Chung, Soo Yoon; Seo, Jae Seung; Kim, Young Jin; Choi, Byoung Wook; Lee, Sun Hwa; Cho, Sang Ho

2006-01-01

The purpose of this study was to evaluate retrospectively the differential CT features of bronchioloalveolar carcinoma (BAC) mimicking pneumonia and infectious pneumonia at the lung periphery. CT images were reviewed in 47 patients with focal areas of parenchymal opacification at the lung periphery. We evaluated the presence of ground-glass attenuation, marginal conspicuity of the lesion, CT angiogram sign, air-bronchogram sign, a bubble-like low-attenuation area within the lesion, presence of pleural thickening and retraction associated with the lesion, presence of pleural effusion and extra-pleural fatty hypertrophy, presence of bronchial wall thickening proximal to the lesion, and air-trapping in the normal lung near the lesion. BAC (n=18) depicted the presence of a bubble-like low-attenuation area within the lesion, whereas infectious pneumonia (n=29) represented the pleural thickening associated with the lesion and bronchial wall thickening proximal to the lesion (P 0.05). The focal areas of the parenchymal opacification on the CT images may suggest infectious pneumonia rather than BAC when they show bronchial wall thickening proximal to the lesion and pleural thickening associated with the lesion, whereas BAC is characterized as the presence of a bubble-like low attenuation area within the tumor. (orig.)

Ability of FDG PET and CT radiomics features to differentiate between primary and metastatic lung lesions.

Science.gov (United States)

Kirienko, Margarita; Cozzi, Luca; Rossi, Alexia; Voulaz, Emanuele; Antunovic, Lidija; Fogliata, Antonella; Chiti, Arturo; Sollini, Martina

2018-04-06

To evaluate the ability of CT and PET radiomics features to classify lung lesions as primary or metastatic, and secondly to differentiate histological subtypes of primary lung cancers. A cohort of 534 patients with lung lesions were retrospectively studied. Radiomics texture features were extracted using the LIFEx package from semiautomatically segmented PET and CT images. Histology data were recorded in all patients. The patient cohort was divided into a training and a validation group and linear discriminant analysis (LDA) was performed to classify the lesions using both direct and backward stepwise methods. The robustness of the procedure was tested by repeating the entire process 100 times with different assignments to the training and validation groups. Scoring metrics included analysis of the receiver operating characteristic curves in terms of area under the curve (AUC), sensitivity, specificity and accuracy. Radiomics features extracted from CT and PET datasets were able to differentiate primary tumours from metastases in both the training and the validation group (AUCs 0.79 ± 0.03 and 0.70 ± 0.04, respectively, from the CT dataset; AUCs 0.92 ± 0.01 and 0.91 ± 0.03, respectively, from the PET dataset). The AUC cut-off thresholds identified by LDA using direct and backward elimination strategies were -0.79 ± 0.06 and -0.81 ± 0.08, respectively (CT dataset) and -0.69 ± 0.05 and -0.68 ± 0.04, respectively (PET dataset). For differentiation between primary subgroups based on CT features, the AUCs in the training and validation groups were 0.81 ± 0.02 and 0.69 ± 0.04 for adenocarcinoma (Adc) vs. squamous cell carcinoma (Sqc) or "Other", 0.85 ± 0.02 and 0.70 ± 0.05 for Sqc vs. Adc or Other, and 0.77 ± 0.03 and 0.57 ± 0.05 for Other vs. Adc or Sqc. The same analyses for the PET data revealed AUCs of 0.90 ± 0.10 and 0.80 ± 0.04, 0.80 ± 0.02 and 0.61 ± 0.06, and 0.97 ± 0

Nodule detection methods using autocorrelation features on 3D chest CT scans

International Nuclear Information System (INIS)

Hara, T.; Zhou, X.; Okura, S.; Fujita, H.; Kiryu, T.; Hoshi, H.

2007-01-01

Lung cancer screening using low dose X-ray CT scan has been an acceptable examination to detect cancers at early stage. We have been developing an automated detection scheme for lung nodules on CT scan by using second-order autocorrelation features and the initial performance for small nodules (< 10 mm) shows a high true-positive rate with less than four false-positive marks per case. In this study, an open database of lung images, LIDC (Lung Image Database Consortium), was employed to evaluate our detection scheme as an consistency test. The detection performance for solid and solitary nodules in LIDC, included in the first data set opened by the consortium, was 83% (10/12) true-positive rate with 3.3 false-positive marks per case. (orig.)

Clinical features and CT scan findings of supratentorial ependymomas and ependymoblastomas

International Nuclear Information System (INIS)

Hanakita, Junya; Handa, Hajime

1984-01-01

The clinical courses and CT scan findings of 12 cases of supratentorial ependymoma and ependymoblastoma were reviewed. The age of the patient of ependymoma ranged from 3 years to 34 years, with an average age of 16 years. The follow-up time ranged from 2 months to 9 years and 10 months. All of the six patients are still alive. The age of the patients of ependymoblastoma ranged from 7 months to 34 years, with an average age of 17 years. During the follow-up period from 2 weeks to 6 years and 4 months, four patients died. Supratentorial ependymomas and ependymoblastomas show the following characteristic features of CT scans: 1. Calcification: The incidence of calcification was 50% in ependymoma-group, and 100% in ependymoblastoma-group. 2. Cyst formation, ring-enhancement: The cyst formation was noticed in both groups. In ependymoma-group a smooth ring-enhancement pattern and the strongly enhanced mural nodule-like contour were found, but in ependymoblastoma-group, the cyst wall was enhanced in irregular shape. 3. Perifocal edema and mass effect: Considerable mass effect was noticed in both groups. Perifocal edema was slight in many cases of ependymoma-group, but mostly prominent in ependymoblastoma-group. 4. CT scan findings of recurrent tumor: In ependymoma-group, recurrent tumor showed the same characteristics of CT scan as the initial ones. In ependymoblastoma-group, cystic portion decreased in size and irregular shaped solid portion increased in recurrence. (author)

Motion estimation and compensation in dynamic spiral CT reconstruction

International Nuclear Information System (INIS)

Kimdon, J.; Grangeat, P.; Koenig, A.; Bonnet, St.

2004-01-01

Respiratory and cardiac motion causes blurring in dynamic X-ray Computed Tomography (CT). Fast scans reduce this problem, but they require a higher radiation dose per time period to maintain the signal to noise ratio of the resulting images, thereby magnifying the health risk to the patient. As an alternative to increased radiation, our team has already developed a cone-beam reconstruction algorithm based on a dynamic particle model that estimates, predicts, and compensates for respiratory motion in circular X-ray CT. The current paper presents an extension of this method to spiral CT, applicable to modern multi-slice scanners that take advantage of the speed and dose benefits of helical trajectories. We adapted all three main areas of the algorithm: backprojection, prediction, and compensation/accumulation. In backprojection, we changed the longitudinal re-binning technique, filter direction, and the method of enforcing the data sufficiency requirements. For prediction, we had to be careful of objects appearing and disappearing as the scanner bed advanced. For compensation/accumulation, we controlled the reconstruction time and combined images to cover a greater longitudinal extent for each phase in the respiratory or cardiac cycle. Tests with moving numerical phantoms demonstrate that the algorithm successfully improves the temporal resolution of the images without increasing the dose or reducing the signal-to-noise ratio. (authors)

Semiquantifying regional cerebral blood flow by dynamic CT scanning

International Nuclear Information System (INIS)

Takeuchi, Totaro; Kasahara, Eishi; Takahashi, Eriko; Kojima, Seiichi; Ogawa, Haruhiko; Suzuki, Keiko; Miyamae, Tatsuya; Yamazaki, Setsuo.

1990-01-01

The study was undertaken to evaluate the semi-quantitative significance of the absolute value obtained by calculating the regional cerebral blood flow index (rCBFI) from dynamic CT in comparison with SPECT. rCBFI was calculated from mean transit time (MTT) and blood capacity index (BCI) obtained by rapidly infusing 50 ml of Omnipurk into the elbow vein by the use of Hitachi's W-600. [rCBFI=BCI/MTT unit/sec (U/S)] measurment of the rCBF by SPECT was made according to the semi-quantitative method by Matsuda et al. by the use of SHIMADZU's improved type HEADTOME SET-050 with rapid infusion of 123 I-IMP in 3.5 m Ci from the elbow vein. Patients in whom no abnormality was observed in the cardiopulmonary function were enrolled as subjects. The rCBFI in each intracranial site was calculated from dynamic CT in 10 normal adults (aged 35-60, averaging 46.7) as subjects and compared with the rCBF obtained from SPECT in the same cases and same site. Comparative investigation was made similarly between rCBFI and rCBF regarding 10 patients with tracranial diseases (age 29-65, averaging 51.2). The mean rCBFIs in the normal adults obtained from dynamic CT were 1.15±0.18 U/S in the frontal lobar cortex, 1.28±0.19 U/S in the temporal lobar cortex, 1.43±0.1 U/S in the occipital lobar cortex, 1.27±0.2 U/S in the basal ganglia region and 0.43±0.1 U/S in the white matter. On the other hand, the mean rCBFs by SPECT were 47.36±3.93 ml/100 g/min, 55.19±2.22 ml/100 g/min, 61.92±5.42 ml/100 g/min, 54.38±3.51 ml/100 g/min and 38.68±6.18 ml/100 g/min, respectively. Positive correlation was observed between rCBFIs and rCBFs of 10 normal adults and 10 patients with intracranial disease, totalling 20 cases (r=0.79, P<0.005). The rCBFI by dynamic CT has a correlation with the rCBF by SPECT, suggesting the possibility of its evaluation as an absolute value, though semi-quantitatively. (author)

CT features of peritoneal and mesenteric involvement in pediatric malignancies. Experience from thirteen cases

International Nuclear Information System (INIS)

Grenier, N.; Filiatrault, D.; Garel, L.; Dube, J.; Paille, P.; Grenier, N.

1986-01-01

A retrospective study of all patients presenting with abdominal malignancies since November 1982 was undertaken in order to assess the CT features of peritoneal and mesenteric involvement in childhood. Thirteen cases, including 4 cases of malignant lymphomas, 1 case of Hodgkin's disease, 5 cases of adrenal tumors and 3 cases of ovarian tumors, were selected. Providing a good technique, CT appears as the best imaging modality of the mesentery. CT is also reliable in showing peritoneal implants, even without ascites. A high quality vascular opacification is needed in order to recognize the involvement of the lesser omentum (6/13 cases in our series). Precise knowledge of the intra-abdominal extension of the primary neoplasm has a definite impact upon the surgical indications and therefore upon the prognosis [fr

Asbestosis and other pulmonary fibrosis in asbestos-exposed workers: high-resolution CT features with pathological correlations

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Arakawa, Hiroaki [Dokkyo Medical University, Department of Radiology, Mibu, Tochigi (Japan); Kishimoto, Takumi [Okayama Rosai Hospital, Asbestos Research Center, Okayama (Japan); Ashizawa, Kazuto [Nagasaki University Graduate School of Biomedical Sciences, Department of Clinical Oncology, Nagasaki (Japan); Kato, Katsuya [Kawasaki Medical School, Department of Diagnostic Radiology 2, Okayama (Japan); Okamoto, Kenzo [Hokkaido Chuo Hospital, Department of Pathology, Iwamizawa, Hokkaido (Japan); Honma, Koichi [Dokkyo Medical University, Department of Pathology, Mibu, Tochigi (Japan); Hayashi, Seiji [National Hospital Organization Kinki-Chuo Chest Medical Center, Osaka (Japan); Akira, Masanori [National Hospital Organization Kinki-Chuo Chest Medical Center, Department of Radiology, Osaka (Japan)

2016-05-15

The purpose was to identify distinguishing CT features of pathologically diagnosed asbestosis, and correlate diagnostic confidence with asbestos body burden. Thirty-three workers (mean age at CT: 73 years) with clinical diagnoses of asbestosis, who were autopsied (n = 30) or underwent lobectomy (n = 3), were collected. Two radiologists independently scored high-resolution CT images for various CT findings and the likelihood of asbestosis was scored. Two pathologists reviewed the pathology specimens and scored the confidence of their diagnoses. Asbestos body count was correlated with CT and pathology scores. Pathologically, 15 cases were diagnosed as asbestosis and 18 cases with various lung fibroses other than asbestosis. On CT, only the score of the subpleural curvilinear lines was significantly higher in asbestosis (p = 0.03). Accuracy of CT diagnosis of asbestosis with a high confidence ranged from 0.73 to 0.79. Asbestos body count positively correlated with CT likelihood of asbestosis (r = 0.503, p = 0.003), and with the confidence level of pathological diagnosis (r = 0.637, p < 0.001). Subpleural curvilinear lines were the only clue for the diagnosis of asbestosis. However, this was complicated by other lung fibrosis, especially at low asbestos body burden. (orig.)

Ventilation imaging of the paranasal sinuses using xenon-enhanced dynamic single-energy CT and dual-energy CT: a feasibility study in a nasal cast

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Thieme, Sven F.; Helck, Andreas D.; Reiser, Maximilian F.; Johnson, Thorsten R.C. [Ludwig Maximilians University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); Moeller, Winfried; Eickelberg, Oliver [Institute for Lung Biology and Disease (iLBD) and Comprehensive Pneumology Center (CPC), Helmholtz Zentrum Muenchen, Neuherberg, Munich (Germany); Becker, Sven [Ludwig-Maximilians-Universitaet, Department of Otorhinolaryngology - Head and Neck Surgery, Munich (Germany); Schuschnig, Uwe [Pari Pharma GmbH, Graefelfing (Germany)

2012-10-15

To show the feasibility of dual-energy CT (DECT) and dynamic CT for ventilation imaging of the paranasal sinuses in a nasal cast. In a first trial, xenon gas was administered to a nasal cast with a laminar flow of 7 L/min. Dynamic CT acquisitions of the nasal cavity and the sinuses were performed. This procedure was repeated with pulsating xenon flow. Local xenon concentrations in the different compartments of the model were determined on the basis of the enhancement levels. In a second trial, DECT measurements were performed both during laminar and pulsating xenon administration and the xenon concentrations were quantified directly. Neither with dynamic CT nor DECT could xenon-related enhancement be detected in the sinuses during laminar airflow. Using pulsating flow, dynamic imaging showed a xenon wash-in and wash-out in the sinuses that followed a mono-exponential function with time constants of a few seconds. Accordingly, DECT revealed xenon enhancement in the sinuses only after pulsating xenon administration. The feasibility of xenon-enhanced DECT for ventilation imaging was proven in a nasal cast. The superiority of pulsating gas flow for the administration of gas or aerosolised drugs to the paranasal sinuses was demonstrated. (orig.)

Functioning islet cell tumor of the pancreas. Localization with dynamic spiral CT

International Nuclear Information System (INIS)

Chung, M.J.; Choi, B.I.; Han, J.K.; Chung, J.W.; Han, M.C.; Bae, S.H.

1997-01-01

Purpose: The purpose of this study was to evaluate the usefulness of dynamic spiral CT, including multidimensional reformation, in the detection and localization of islet cell tumors of the pancreas. Material and Methods: Seven patients with histopathologically proven functioning islet cell tumors of the pancreas were studied with 2-phase contrast-enhanced spiral CT. Scanning of the arterial phase and late phase was started 30 s and 180 s, respectively, after injection of 100 ml of contrast medium at a rate of 3 ml/s. Results: Axial images in the arterial phase depicted the lesions in 5 patients, but in the late phase in only one patient. Multiplanar reformatted images of the arterial phase depicted the lesions in all 7 patients. Maximal intensity projection images demonstrated all lesions with information of their relationship to the vascular structure. Conclusion: Dynamic spiral CT with scanning during the arterial phase and retrospective multidimensional reformation is useful for preoperative detection and localization of small islet cell tumors of the pancreas. (orig.)

CT features of neutropenic enterocolitis in adult patients with hematological diseases undergoing chemotherapy

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Vogel, M.N.; Brodoefel, H.; Claussen, C.D.; Horger, M. [Tuebingen Univ. (Germany). Dept. of Diagnostic and Interventional Radiology; Goeppert, B. [Heidelberg Univ. (Germany). Inst. of Pathology; Maksimovic, O.; Faul, C. [Tuebingen Univ. (Germany). Dept. of Internal Medicine-Oncology

2010-12-15

Purpose: This study investigates the features of neutropenic enterocolitis (NE) in adults. Materials and Methods: Chart and radiology report reviews were used to identify neutropenic patients with hematological diseases undergoing chemotherapy, who had CT scans for the clarification of abdominal symptoms between October 2003 and October 2009. Patients with any cause for enteritis other than NE were excluded. The scans were analyzed with respect to imaging features and location. Morphological findings were correlated with clinical data. Results: Thirty-one patients with NE (median age 46 years; range 20 - 75) could be identified. Wall thickening and hyperemia could be found in all bowel segments from jejunum to rectum. The right hemicolon was the most frequent location in 19 patients (61 %). Involvement was generalized in 6 patients (19 %) and segmental in 25 cases (81 %). The longer the duration of neutropenia, the more likely generalized involvement of the bowel was. In 8 patients who underwent CT follow-up, the appearance of bowel segments had completely (n = 5) or partially (n = 3) returned to normal at the latest 14 days after the initial diagnosis. Eight patients (26 %) died 1 - 78 days after NE, 7 of who had previously recovered from NE. Conclusion: CT findings are useful for the diagnosis of NE and should be considered even in the presence of isolated small bowel involvement. The terms NE and typhlitis should thus no longer be used synonymously. (orig.)

Comparative Study of the CT Findings and Clinical Features in Pediatric and Adult Sialadenitis

International Nuclear Information System (INIS)

Han, Jong Kyu; Jo, Seong Shik; Kim, Sang Won; Kim, Young Tong; Shin, Hyeong Cheol; Kim, Il Young; Lee, Yong Man

2010-01-01

We wanted to compare the CT findings and clinical features of parotitis and submandibular sialadenitis in children and adults and to evaluate the statistical significance of these in different age groups and the usefulness of a CT scan. Ninety-seven adults and 36 pediatric patients with sialadenitis were included in this retrospective study. Regardless of the site of involvement, we evaluated the CT findings and clinical manifestations between the pediatric and adult groups, and between the pediatric and adult parotitis and submandibular sialadenitis groups. At last, all the patients were classified into seven age groups. Abscess formations were more prominent in the parotitis groups, and sialiths were more common in the submandibular sialadenitis group with the lowest incidence in the young children group (≤ 10 years). Cellulitis seen on a CT scan showed a higher incidence in the adult parotitis group, and this finding was closely connected with pain. A number of patients showed cervical lymphadenitis on a CT scan and this coincided with lymph node palpation. Tonsillitis associated sialadenitis was common in the pediatric group. The therapeutic durations were longer in the pediatric parotitis patient group and the adult submandibular sialadenitis group. CT scans were very helpful to evaluate for abscess, stone, lymphadenitis and estimating the associated clinical manifestations such as swelling, palpable lymph nodes, pain with operation and the therapeutic plan

An application of dynamic CT for diagnosis of abnormal external ocular muscle movement

International Nuclear Information System (INIS)

Tomita, Kazumi; Ogura, Yuuko; Takeshita, Gen; Koga, Sukehiko; Katada, Kazuhiro; Anno, Hirofumi.

1993-01-01

To evaluate the movements of retrobulbar structures radiologically, we have developed a new technique called 'external ocular muscle movement CT' (EOM CT), in which dynamic CT scanning is performed while the patient performs controlled eye movements. This new technique was applied in one volunteer and 72 patients with external ophthalmoplegia due to orbital mass lesion, hyperthyroid ophthalmopathy, blowout fracture, and other retrobulbar lesions. EOM CT permits the assessment of extraocular muscle contraction in cases of blowout fracture, the evaluation of muscular contraction in hypertrophy of the extraocular muscles, and the diagnosis of adhesions between the extraocular muscles and intraorbital masses. Radiation dose to the lens from EOM CT was measured using a phantom and TLD, and was compared with that of conventional CT scanning with a 5 mm slice thickness. The dose to the lens from EOM CT was three times higher than that for conventional CT in axial scanning, but in the coronal section of the retrobulbar region, the dose to the lens from EOM CT decreases to one twelfth of that of conventional CT. EOM CT promises to be a powerful modality for functional evaluation of the extraocular muscles and other retrobulbar structures. (author)

Interplay of static and dynamic features in biomimetic smart ears.

Science.gov (United States)

Pannala, Mittu; Meymand, Sajjad Zeinoddini; Müller, Rolf

2013-06-01

Horseshoe bats (family Rhinolophidae) have sophisticated biosonar systems with outer ears (pinnae) that are characterized by static local shape features as well as dynamic non-rigid changes to their overall shapes. Here, biomimetic prototypes fabricated from elastic rubber sheets have been used to study the impact of these static and dynamic features on the acoustic device characteristics. The basic shape of the prototypes was an obliquely truncated horn augmented with three static local shape features: vertical ridge, pinna-rim incision and frontal flap (antitragus). The prototype shape was deformed dynamically using a one-point actuation mechanism to produce a biomimetic bending of the prototype's tip. In isolation, the local shape features had little impact on the device beampattern. However, strong interactions were observed between these features and the overall deformation. The further the prototype tip was bent down, the stronger the beampatterns associated with combinations of multiple features differed from the upright configuration in the prominence of sidelobes. This behavior was qualitatively similar to numerical predictions for horseshoe bats. Hence, the interplay between static and dynamic features could be a bioinspired principle for affecting large changes through the dynamic manipulations of interactions that are sensitive to small geometrical changes.

SU-F-R-21: The Stability of Radiomics Features On 4D FDG-PET/CT Images

Energy Technology Data Exchange (ETDEWEB)

Ma, C [Shandong Cancer Hospital and Institute, Jinan, Shandong (China)

2016-06-15

Purpose: The aim of our study was to perform a stability analysis of 4D PET-derived features in non-small cell lung carcinoma (NSCLC) based on six different respiratory phases. Methods: The 4D FDG-PET/CT respiratory phases were labeled as T0%, T17%, T33%,T50%, T67%, T83% phases, with the T0% phase approximately corresponding to the normal end-inspiration. Lesions were manually delineated based on fused PET-CT, using a standardized clinical delineation protocol. Six texture parameters were analyzed. Results: Results showed that the majority of assessed features had a low stability such as Homogeneity (0.385–0.416), Dissimilarity (3.707–3.861), Angular two moments (0.013–0.019), Contrast (39.782–49.562), Entropy(4.683–5.002) and Inverse differential moment (0.317–0.362) on different respiratory phases. Conclusion: This study suggest that further research of quantitative PET imaging features is warranted with respect to respiratory motion.

FIR signature verification system characterizing dynamics of handwriting features

Science.gov (United States)

Thumwarin, Pitak; Pernwong, Jitawat; Matsuura, Takenobu

2013-12-01

This paper proposes an online signature verification method based on the finite impulse response (FIR) system characterizing time-frequency characteristics of dynamic handwriting features. First, the barycenter determined from both the center point of signature and two adjacent pen-point positions in the signing process, instead of one pen-point position, is used to reduce the fluctuation of handwriting motion. In this paper, among the available dynamic handwriting features, motion pressure and area pressure are employed to investigate handwriting behavior. Thus, the stable dynamic handwriting features can be described by the relation of the time-frequency characteristics of the dynamic handwriting features. In this study, the aforesaid relation can be represented by the FIR system with the wavelet coefficients of the dynamic handwriting features as both input and output of the system. The impulse response of the FIR system is used as the individual feature for a particular signature. In short, the signature can be verified by evaluating the difference between the impulse responses of the FIR systems for a reference signature and the signature to be verified. The signature verification experiments in this paper were conducted using the SUBCORPUS MCYT-100 signature database consisting of 5,000 signatures from 100 signers. The proposed method yielded equal error rate (EER) of 3.21% on skilled forgeries.

Imaging features of portal biliopathy: Frequency of involvement patterns with emphasis on MRCP

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Ozkavukcu, Esra [Ankara University School of Medicine, Department of Radiology (Turkey)], E-mail: eozkavukcu@gmail.com; Erden, Ayse; Erden, Ilhan [Ankara University School of Medicine, Department of Radiology (Turkey)

2009-07-15

Purpose: To investigate the imaging features of portal biliopathy with emphasis on MR cholangiopancreatography (MRCP). The ancillary vascular findings of portal biliopathy were also evaluated by accompanying MR portography, dynamic contrast-enhanced (CE) CT, and dynamic CE MRI studies. Materials and methods: Sixteen patients with portal cavernoma were included in the study. Patients had undergone MRCP (n = 16) studies accompanied by MR portography (n = 13), dynamic CE CT (n = 3) or dynamic CE MRI (n = 2) of the liver. Two patients had undergone both dynamic CE CT and dynamic CE MRI. Two radiologists evaluated all the examinations together, retrospectively. MRCP images were analyzed for the presence of biliary stenosis, upstream (prestenotic) dilatation, wavy appearance of the bile ducts, angulation of the common bile duct (CBD), and choledocholithiasis. MR portography, dynamic CE CT and dynamic CE MRI studies were evaluated for the existence of portal cavernomas, and the presence of gall bladder/choledochal varices. Results: All patients had signs of portal biliopathy on MRCP. Frequencies of the biliary findings on MRCP were as follows: biliary stenosis, 93.7%; upstream dilatation, 68.7%; wavy appearance of the biliary tree, 87.5%; angulation of the CBD, 75%. None of the patients had choledocholithiasis. Frequencies of the ancillary vascular findings detected on CE studies were as follows: gall bladder varices, 100%, choledochal varices, 93.7%. Conclusion: MRCP features of portal biliopathy in order to their frequencies were as follows: biliary stenosis, wavy appearance of the bile ducts, angulation of the CBD, and upstream dilatation of the bile ducts.

Estimation of lung tumor position from multiple anatomical features on 4D-CT using multiple regression analysis.

Science.gov (United States)

Ono, Tomohiro; Nakamura, Mitsuhiro; Hirose, Yoshinori; Kitsuda, Kenji; Ono, Yuka; Ishigaki, Takashi; Hiraoka, Masahiro

2017-09-01

To estimate the lung tumor position from multiple anatomical features on four-dimensional computed tomography (4D-CT) data sets using single regression analysis (SRA) and multiple regression analysis (MRA) approach and evaluate an impact of the approach on internal target volume (ITV) for stereotactic body radiotherapy (SBRT) of the lung. Eleven consecutive lung cancer patients (12 cases) underwent 4D-CT scanning. The three-dimensional (3D) lung tumor motion exceeded 5 mm. The 3D tumor position and anatomical features, including lung volume, diaphragm, abdominal wall, and chest wall positions, were measured on 4D-CT images. The tumor position was estimated by SRA using each anatomical feature and MRA using all anatomical features. The difference between the actual and estimated tumor positions was defined as the root-mean-square error (RMSE). A standard partial regression coefficient for the MRA was evaluated. The 3D lung tumor position showed a high correlation with the lung volume (R = 0.92 ± 0.10). Additionally, ITVs derived from SRA and MRA approaches were compared with ITV derived from contouring gross tumor volumes on all 10 phases of the 4D-CT (conventional ITV). The RMSE of the SRA was within 3.7 mm in all directions. Also, the RMSE of the MRA was within 1.6 mm in all directions. The standard partial regression coefficient for the lung volume was the largest and had the most influence on the estimated tumor position. Compared with conventional ITV, average percentage decrease of ITV were 31.9% and 38.3% using SRA and MRA approaches, respectively. The estimation accuracy of lung tumor position was improved by the MRA approach, which provided smaller ITV than conventional ITV. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

comparison of clinical features and CT findings between atypical thymoma and thymic carcinoma

International Nuclear Information System (INIS)

Wang Xiangyang; Tan Ye; Chen Juan; Wei Jiahu; Pan Jishun; Du Jun; Zhou Cheng

2011-01-01

Objective: To investigate the differences and the similarities of clinical presentations and CT features between type B3 thymoma (atypical thymoma) and type C thymoma (thymic carcinoma) in the WHO classification of thymic epithelial tumors. Methods: Complete CT findings of thirty cases of type B3 and seventeen cases of type C thymic epithelial tumors confirmed by histopathology according to WHO 2004 Classification System and clinical features including the prognosis of each case were reviewed retrospectively. Statistical analyses of the data for the age and the long diameter were performed with Independent-Samples t test between the two groups. Statistical analysis for gender, association with myasthenia gravis, method of the operation, contours, shapes, calcification,necrosis, enhancement pattern of the tumors on CT, presence of mediastinal lymphadenopathy, invasion of mediastinal fat, chest wall, pericardium, great vessel, pleural mediastinum, metastasis to the plural, pleural effusion, distant metastasis were performed with Fisher exact test. Kaplan-Meier method was employed for survival analysis. Results: Clinical data: the average age of type B3 group was significantly younger (t=-2.905, P=0.006). 90.0% (27/30) of patients in type B3 group were complicated by myasthenia gravis, while only 5.9% (1/17) of patients in type C group were complicated by myasthenia gravis. The difference between the two groups was statistically significant (P=0.000). The ratio of complete resection of type B3 group (80.0%) was significantly higher than that in type C group (P=0.001), 70.6% (12/17) of patients in type C group died within 2 years after surgical resection, while only 20.0% (6/30) of patients in type B3 group died within one to nine years after surgical resection. Three years' survival ratio of C group was 29.4%, and five years' survival ratio of C group was lower than 14.7%, which was significantly lower than B3 group five years' survival ratio was 94.7%), which was

Can lymphovascular invasion be predicted by preoperative multiphasic dynamic CT in patients with advanced gastric cancer?

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Ma, Zelan; Liang, Cuishan; Huang, Xiaomei; Liu, Zaiyi [Southern Medical University, Guangzhou, Guangdong (China); Guangdong General Hospital, Guangdong Academy of Medical Sciences, Department of Radiology, Guangzhou, Guangdong Province (China); Liang, Changhong; Huang, Yanqi [Guangdong General Hospital, Guangdong Academy of Medical Sciences, Department of Radiology, Guangzhou, Guangdong Province (China); He, Lan [Guangdong General Hospital, Guangdong Academy of Medical Sciences, Department of Radiology, Guangzhou, Guangdong Province (China); South China University of Technology, School of Medicine, Guangzhou, Guangdong (China); Chen, Xin [The Affiliated Guangzhou First People' Hospital, Guangzhou Medical University, Department of Radiology, Guangzhou, Guangdong (China); Xiong, Yabing [Southern Medical University, Guangzhou, Guangdong (China)

2017-08-15

To determine whether multiphasic dynamic CT can preoperatively predict lymphovascular invasion (LVI) in advanced gastric cancer (AGC). 278 patients with AGC who underwent preoperative multiphasic dynamic CT were retrospectively recruited. Tumour CT attenuation difference between non-contrast and arterial (Δ{sub AP}), portal (Δ{sub PP}) and delayed phase (Δ{sub DP}), tumour-spleen attenuation difference in the portal phase (Δ{sub T-S}), tumour contrast enhancement ratios (CERs), tumour-to-spleen ratio (TSR) and tumour volumes were obtained. All CT-derived parameters and clinicopathological variables associated with LVI were analysed by univariate analysis, followed by multivariate and receiver operator characteristics (ROC) analysis. Associations between CT predictors for LVI and histopathological characteristics were evaluated by the chi-square test. Δ{sub PP} (OR, 1.056; 95% CI: 1.032-1.080) and Δ{sub T-S} (OR, 1.043; 95% CI: 1.020-1.066) are independent predictors for LVI in AGC. Δ{sub PP}, Δ{sub T-S} and their combination correctly predicted LVI in 74.8% (AUC, 0.775; sensitivity, 88.6%; specificity, 54.1%), 68.7% (AUC, 0.747; sensitivity, 68.3%; specificity, 69.4%) and 71.7% (AUC, 0.800; sensitivity, 67.6%; specificity, 77.8%), respectively. There were significant associations between CT predictors for LVI with tumour histological differentiation and Lauren classification. Multiphasic dynamic CT provides a non-invasive method to predict LVI in AGC through quantitative enhancement measurement. (orig.)

CT and MR imaging features in patients with intracranial dolichoectasia

Energy Technology Data Exchange (ETDEWEB)

Tien, Kuang Lung; Yu, In Kyu; Yoon, Sook Ja; Yoon, Yong Kyu [Eulji College of Medicine, Eulji Hospital, Seoul (Korea, Republic of)

2000-02-01

To describe the CT and MR imaging features in patients with intracranial dolichoectasia. The CT (n=3D21), MR (n=3D20) and MRA (n=3D11) imaging features seen in 28 patients (M:F=3D12:16 aged between 65 and 82 (mean, 65) years) with intracranial dolichoectasia were retrospectively reviewed with regard to involved sites, arterial changes (maximum diameter, wall calcification, high signal intensity in the involved artery, as seen on T1-weighted MR images), infarction, hemorrhagic lesion, compression of brain parenchyma or cranial nerves, hydrocephalus and brain atrophy. Involved sites were classified as either type 1 (involvement of only the posterior circulation), type 2 (only the anterior circulation), or type 3 (both). In order of frequency, involved sites were type 1 (43%), type 3 (36%) and type 2 (22%). Dolichoectasia was more frequently seen in the posterior circulation (79%) than in the anterior (57%). Arterial changes as seen on T1-weighted MR images, included dolichoectasia (mean maximum diameter 7.4 mm in the distal internal carotid artery, and 6.7 mm in the basilar artery), wall calcification (100% in involved arteries) and high signal intensity in involved. Cerebral infarction in the territory of the involved artery was found in all patients, and a moderate degree of infarct was 87%. Hemorrhagic lesions were found in 19 patients (68%); these were either lobar (53%), petechial (37%), or subarachnoid (16%), and three patients showed intracranial aneurysms, including one case of dissecting aneurysm. In 19 patients (68%), lesions were compressed lesions by the dolichoectatic arteries, and were found-in order of descending frequency-in the medulla, pons, thalamus, and cerebellopontine angle cistern. Obstructive hydrocephalus was found in two patients (7%), and 23 (82%) showed a moderate degree of brain atrophy. In patients with intracranial dolichoectasia, moderate degrees of cerebral infarction and brain atrophy in the territory of involved arteries, as well as

WE-G-207-05: Relationship Between CT Image Quality, Segmentation Performance, and Quantitative Image Feature Analysis

Energy Technology Data Exchange (ETDEWEB)

Lee, J; Nishikawa, R [University of Pittsburgh, Pittsburgh, PA (United States); Reiser, I [The University of Chicago, Chicago, IL (United States); Boone, J [UC Davis Medical Center, Sacramento, CA (United States)

2015-06-15

Purpose: Segmentation quality can affect quantitative image feature analysis. The objective of this study is to examine the relationship between computed tomography (CT) image quality, segmentation performance, and quantitative image feature analysis. Methods: A total of 90 pathology proven breast lesions in 87 dedicated breast CT images were considered. An iterative image reconstruction (IIR) algorithm was used to obtain CT images with different quality. With different combinations of 4 variables in the algorithm, this study obtained a total of 28 different qualities of CT images. Two imaging tasks/objectives were considered: 1) segmentation and 2) classification of the lesion as benign or malignant. Twenty-three image features were extracted after segmentation using a semi-automated algorithm and 5 of them were selected via a feature selection technique. Logistic regression was trained and tested using leave-one-out-cross-validation and its area under the ROC curve (AUC) was recorded. The standard deviation of a homogeneous portion and the gradient of a parenchymal portion of an example breast were used as an estimate of image noise and sharpness. The DICE coefficient was computed using a radiologist’s drawing on the lesion. Mean DICE and AUC were used as performance metrics for each of the 28 reconstructions. The relationship between segmentation and classification performance under different reconstructions were compared. Distributions (median, 95% confidence interval) of DICE and AUC for each reconstruction were also compared. Results: Moderate correlation (Pearson’s rho = 0.43, p-value = 0.02) between DICE and AUC values was found. However, the variation between DICE and AUC values for each reconstruction increased as the image sharpness increased. There was a combination of IIR parameters that resulted in the best segmentation with the worst classification performance. Conclusion: There are certain images that yield better segmentation or classification

CT features of primary epiploic appendagitis

International Nuclear Information System (INIS)

Ng, Keng Sin; Tan, Andrew Gee Seng; Chen, Kevin K'o Wen; Wong, Siew Kune; Tan, How Ming

2006-01-01

Objective: The aim of this study is to describe the computed tomography (CT) findings of primary epiploic appendagitis (PEA). Methods: We reviewed the clinical records and CT images of 14 consecutive patients in Singapore who presented with acute abdominal pain from July 2000 to April 2004 and had radiological signs of PEA. Results: Hyperattenuated ring with adjacent fat stranding was present in all the patients. The central high attenuation dot was seen in 42.9% (6/14) of the patients. We observed a lobulated fatty mass in 21.4% (3/14) of our patients. All patients recovered during clinical follow-up. Conclusions: We believe the lobulated appearance of PEA is due to two or more, contiguous infarcted epiploic appendages lying in close proximity. This appearance further aids in the diagnosis of PEA and helps differentiates the condition from omental infarction. Recognizing the CT signs of PEA should allow a confident diagnosis and avoid unnecessary surgery

Dynamic Features for Iris Recognition.

Science.gov (United States)

da Costa, R M; Gonzaga, A

2012-08-01

The human eye is sensitive to visible light. Increasing illumination on the eye causes the pupil of the eye to contract, while decreasing illumination causes the pupil to dilate. Visible light causes specular reflections inside the iris ring. On the other hand, the human retina is less sensitive to near infra-red (NIR) radiation in the wavelength range from 800 nm to 1400 nm, but iris detail can still be imaged with NIR illumination. In order to measure the dynamic movement of the human pupil and iris while keeping the light-induced reflexes from affecting the quality of the digitalized image, this paper describes a device based on the consensual reflex. This biological phenomenon contracts and dilates the two pupils synchronously when illuminating one of the eyes by visible light. In this paper, we propose to capture images of the pupil of one eye using NIR illumination while illuminating the other eye using a visible-light pulse. This new approach extracts iris features called "dynamic features (DFs)." This innovative methodology proposes the extraction of information about the way the human eye reacts to light, and to use such information for biometric recognition purposes. The results demonstrate that these features are discriminating features, and, even using the Euclidean distance measure, an average accuracy of recognition of 99.1% was obtained. The proposed methodology has the potential to be "fraud-proof," because these DFs can only be extracted from living irises.

Giant Serous Cystadenoma of the Pancreas (⩾10 cm: The Clinical Features and CT Findings

Directory of Open Access Journals (Sweden)

Qing-Yu Liu

2016-01-01

Full Text Available Purpose. To report the clinical features and CT manifestations of giant pancreatic serous cystadenoma (≥10 cm. Methods. We retrospectively reviewed the clinical features and CT findings of 6 cases of this entity. Results. All 6 patients were symptomatic. The tumors were 10.2 cm–16.5 cm (median value, 13.0 cm. CT imaging revealed that all 6 cases showed microcystic appearances (n=5 or mixed microcystic and macrocystic appearances (n=1. Five patients with tumors at the distal end of the pancreas received distal pancreatectomy. Among these 5 patients, 2 patients underwent partial transverse colon resection or omentum resection due to close adhesion. One patient whose tumor was located in the pancreatic head underwent pancreaticoduodenectomy; however, due to encasement of the portal and superior mesenteric veins, the tumor was incompletely resected. One patient had abundant draining veins on the tumor surface and suffered large blood loss (700 mL. After 6–49 months of follow-up the 6 patients showed no tumor recurrence or signs of malignant transformation. Conclusions. Giant pancreatic serous cystadenoma necessitates surgical resection due to large size, symptoms, uncertain diagnosis, and adjacent organ compression. The relationship between the tumors and the neighboring organs needs to be carefully assessed before operation on CT image.

Interstitial Features at Chest CT Enhance the Deleterious Effects of Emphysema in the COPDGene Cohort.

Science.gov (United States)

Ash, Samuel Y; Harmouche, Rola; Ross, James C; Diaz, Alejandro A; Rahaghi, Farbod N; Sanchez-Ferrero, Gonzalo Vegas; Putman, Rachel K; Hunninghake, Gary M; Onieva, Jorge Onieva; Martinez, Fernando J; Choi, Augustine M; Bowler, Russell P; Lynch, David A; Hatabu, Hiroto; Bhatt, Surya P; Dransfield, Mark T; Wells, J Michael; Rosas, Ivan O; San Jose Estepar, Raul; Washko, George R

2018-06-05

Purpose To determine if interstitial features at chest CT enhance the effect of emphysema on clinical disease severity in smokers without clinical pulmonary fibrosis. Materials and Methods In this retrospective cohort study, an objective CT analysis tool was used to measure interstitial features (reticular changes, honeycombing, centrilobular nodules, linear scar, nodular changes, subpleural lines, and ground-glass opacities) and emphysema in 8266 participants in a study of chronic obstructive pulmonary disease (COPD) called COPDGene (recruited between October 2006 and January 2011). Additive differences in patients with emphysema with interstitial features and in those without interstitial features were analyzed by using t tests, multivariable linear regression, and Kaplan-Meier analysis. Multivariable linear and Cox regression were used to determine if interstitial features modified the effect of continuously measured emphysema on clinical measures of disease severity and mortality. Results Compared with individuals with emphysema alone, those with emphysema and interstitial features had a higher percentage predicted forced expiratory volume in 1 second (absolute difference, 6.4%; P < .001), a lower percentage predicted diffusing capacity of lung for carbon monoxide (DLCO) (absolute difference, 7.4%; P = .034), a 0.019 higher right ventricular-to-left ventricular (RVLV) volume ratio (P = .029), a 43.2-m shorter 6-minute walk distance (6MWD) (P < .001), a 5.9-point higher St George's Respiratory Questionnaire (SGRQ) score (P < .001), and 82% higher mortality (P < .001). In addition, interstitial features modified the effect of emphysema on percentage predicted DLCO, RVLV volume ratio, 6WMD, SGRQ score, and mortality (P for interaction < .05 for all). Conclusion In smokers, the combined presence of interstitial features and emphysema was associated with worse clinical disease severity and higher mortality than was emphysema alone. In addition, interstitial features

Three-dimensional visualization and measurement of water distributions in PEFC by dynamic CT method on neutron radiography

International Nuclear Information System (INIS)

Hashimoto, Michinori; Murakawa, Hideki; Sugimoto, Katsumi; Asano, Hitoshi; Takenaka, Nobuyuki; Mochiki, Koh-ichi

2011-01-01

Visualization of dynamic three-dimensional water behavior in a PEFC stack was carried out by neutron CT for clarifying water effects on performances of a Polymer Electrolyte Fuel Cell (PEFC) stack. Neutron radiography system at JRR-3 in Japan Atomic Energy Agency was used. An operating stack with three cells based on Japan Automobile Research Institute standard was visualized. A consecutive CT reconstruction method by rotating the fuel stack continuously was developed by using a neutron image intensifier and a C-MOS high speed video camera. The dynamic water behavior in channels in the operating PEFC stack was clearly visualized 15 sec in interval by the developed dynamic neutron CT system. From the CT reconstructed images, evaluation of water amount in each cell was carried out. It was shown that the water distribution in each cell was correlated well with power generation characteristics in each cell. (author)

CT, Magnetic Resonance, and 18F-Fluorodeoxyglucose Positron Emission Tomography/CT Imaging Features of Mucosa-Associated Lymphoid Tissue Lymphoma Involving Medial Rectus Muscle: A Case Report

International Nuclear Information System (INIS)

Lee, Sang Kwon; Choe, Mi Sun

2013-01-01

We report a case of mucosa-associated lymphoid tissue (MALT) lymphoma involving the medial rectus muscle in a 47-year-old man along with CT, MRI, 18 F-fluorodeoxy-glucose positron emission tomography/CT ( 18 F-FDG PET/CT), and pathologic features. The lesion was manifested as a fusiform enlargement isolated to the right medial rectus muscle with involvement of its tendinous insertion. The lesion was isoattenuating to the brain on non-enhanced CT images, showing as isointense to gray matter on fast spin echo T1- and T2-weighted images with fat saturation, and showed homogeneous enhancement on contrast-enhanced CT and MR images. The maximum stan- dardized uptake value on 18 F-FDG PET/CT was 4.9 g/mL. The results of histological and immunohistochemical examinations of the specimen obtained by biopsy of the right medial rectus muscle were consistent with MALT lymphoma. It should be noted that the extraocular muscle (EOM) is a rare location for the involvement of MALT lympho- ma, and MALT lymphoma of the EOM may mimic thyroid orbitopathy.

{sup 18}F-FDG PET/CT imaging versus dynamic contrast-enhanced CT for staging and prognosis of inflammatory breast cancer

Energy Technology Data Exchange (ETDEWEB)

Champion, Laurence; Edeline, Veronique; Giraudet, Anne-Laure; Wartski, Myriam [Service de Medecine Nucleaire, Saint-Cloud (France); Lerebours, Florence [Service d' Oncologie Medicale, Saint-Cloud (France); Cherel, Pascal [Institut Curie, Hopital Rene Huguenin, Service de Radiologie, Saint-Cloud (France); Bellet, Dominique [Service de Medecine Nucleaire, Saint-Cloud (France); Universite Paris Descartes, Pharmacologie Chimique et Genetique and Imagerie, Inserm U1022 CNRS UMR 8151, Faculte des sciences pharmaceutiques et biologiques, Paris (France); Alberini, Jean-Louis [Service de Medecine Nucleaire, Saint-Cloud (France); Universite Versailles Saint-Quentin, Faculte de medecine, Saint-Quentin-en-Yvelines (France)

2013-08-15

Inflammatory breast cancer (IBC) is the most aggressive type of breast cancer with a poor prognosis. Locoregional staging is based on dynamic contrast-enhanced (DCE) CT or MRI. The aim of this study was to compare the performances of FDG PET/CT and DCE CT in locoregional staging of IBC and to assess their respective prognostic values. The study group comprised 50 women (median age: 51 {+-} 11 years) followed in our institution for IBC who underwent FDG PET/CT and DCE CT scans (median interval 5 {+-} 9 days). CT enhancement parameters were net maximal enhancement, net early enhancement and perfusion. The PET/CT scans showed intense FDG uptake in all primary tumours. Concordance rate between PET/CT and DCE CT for breast tumour localization was 92 %. No significant correlation was found between SUVmax and CT enhancement parameters in primary tumours (p > 0.6). PET/CT and DCE CT results were poorly correlated for skin infiltration (kappa = 0.19). Ipsilateral foci of increased axillary FDG uptake were found in 47 patients (median SUV: 7.9 {+-} 5.4), whereas enlarged axillary lymph nodes were observed on DCE CT in 43 patients. Results for axillary node involvement were fairly well correlated (kappa = 0.55). Nineteen patients (38 %) were found to be metastatic on PET/CT scan with a significant shorter progression-free survival than patients without distant lesions (p = 0.01). In the primary tumour, no statistically significant difference was observed between high and moderate tumour FDG uptake on survival, using an SUVmax cut-off of 5 (p = 0.7 and 0.9), or between high and low tumour enhancement on DCE CT (p > 0.8). FDG PET/CT imaging provided additional information concerning locoregional involvement to that provided by DCE CT on and allowed detection of distant metastases in the same whole-body procedure. Tumour FDG uptake or CT enhancement parameters were not correlated and were not found to have any prognostic value. (orig.)

Hydro-dynamic CT preoperative staging of gastric cancer: correlation with pathological findings. A prospective study of 107 cases

International Nuclear Information System (INIS)

D'Elia, F.; Zingarelli, A.; Grani, M.; Palli, D.

2000-01-01

The aim of this study was to evaluate the accuracy of dynamic CT in the preoperative staging of gastric cancer. One hundred seven patients affected by gastric cancer diagnosed by endoscopic biopsy were prospectively staged by dynamic CT prior to tumor resection. After an oral intake of 400-600 ml of tap water and an intravenous infusion of a hypotonic agent, 200 ml of non-ionic contrast agent were administered by power injector using a biphasic technique. The CT findings were prospectively analyzed and correlated with the pathological findings at surgery. The accuracy of dynamic CT for tumor detection was 80 and 99 % in early and advanced gastric cancer, respectively, with overall detection rate of 96 % (103 of 107). Three early (pT1) and one advanced (pT2) cancers were undetected. Tumor stage as determined by dynamic CT agreed with pathological findings in 83 of 107 patients with an overall accuracy of 78 %. The accuracy of CT in detecting increasing degrees of depth of tumor invasion when compared with pathological TNM staging was 20 % (3 of 15) and 87 % (80 of 92) in early and advanced cancer, respectively. The sensitivity, specificity, and accuracy of CT in the preoperative staging (pT3-pT4 vs pT1-pT2) was 93, 90, and 91.6 %, respectively. The sensitivity, specificity, and accuracy of CT in assessing metastasis to regional lymph nodes was 97.2, 65.7, and 87 %, respectively. Computed tomography correctly staged liver metastases in 105 of 107 patients with an overall sensitivity of 87.5 % and specificity of 99 %. The sensitivity of peritoneal involvement was 30 % when ascites or peritoneal nodules were absent. Our findings show that dynamic CT can play a role in the preoperative definition of gastric cancer stage. The results can be used to optimize the therapeutic strategy for each individual patient prior to surgery, thus avoiding unnecessary intervention and allowing careful planning of extended surgery in eligible patients. (orig.)

Correlation between spiral CT features of pericolic infiltration and tumor angiogenesis in colorectal carcinoma

International Nuclear Information System (INIS)

Zhang Ruiping; Li Jianding

2007-01-01

Objective: To investigate the correlation of spiral CT (SCT) features with pathology, microvessel density (MVD), expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2( MMP-2) in colorectal carcinoma. Methods: Forty patients with colorectal carcinoma confirmed by operation were examined by SCT. The resected tumor specimens were immunohistochemically stained for the expression of VEGF, MMP-2 and the calculation of MVD. Results: The accuracy of SCT in depicting the pericolic and wall infiltration was 92.5%. The metastasis rates of colorectal cancer with pericolic infiltration and wall infiltration were 75.0% and 33.3%, respectively, the differences were statistically significant between the two groups (P<0.05). The differences of CT enhancement value, MVD, expressions of VEGF and MMP-2 between the two groups were statistically significant (P<0.05). The enhancement degree of CT had a positive correlation with MVD (P<0.05). Conclusion: SCT is accurate for depicting pericolic and wall infiltration, pericolic infiltration in colorectal carcinoma indicates the tendency of metastasis. The enhancement degree of CT might be used to quantitatively evaluate the tumor angiogenesis, expressions of VEGF and MMP-2 and MVD are closely correlated with the infiltration of colorectal cancer. (authors)

Clear cell sarcoma of the abdominal wall with peritoneal sarcomatosis: CT features

International Nuclear Information System (INIS)

Sabate, J.M.; Fernandez, A.; Torrubia, S.; Villanueva, A.; Monill, J.M.

1999-01-01

Clear cell sarcoma, also called malignant melanoma of soft parts, is an uncommon neoplasm that involves tendons or aponeuroses of the lower extremity. The CT features of a clear cell sarcoma arising from the abdominal wall with later peritoneal dissemination are described. Peritoneal sarcomatosis from soft tissue sarcomas is a very rare condition previously unreported in the radiologic literature. Metastases to peritoneal surfaces must therefore be considered a possible site for systemic dissemination of soft tissue sarcomas. (orig.)

CT features of vasculitides based on the 2012 international chapel hill consensus conference revised classification

International Nuclear Information System (INIS)

Hur, Jee Hye; Chun, Eun Ju; Kim, Hae Young; Kim, Jeong Jae; Lee, Kyung Won; Kwang, Hyon Joo; Yoo, Jin Young

2017-01-01

Vasculitis, characterized by inflammation of vessel walls, is comprised of heterogeneous clinicopathological entities, and thus poses a diagnostic challenge. The most widely used approach for classifying vasculitides is based on the International Chapel Hill Consensus Conference (CHCC) nomenclature system. Based on the recently revised CHCC 2012, we propose computed tomography (CT) features of vasculitides and a differential diagnosis based on location and morphological characteristics. Finally, vasculitis mimics should be differentiated, because erroneous application of immunosuppressive drugs on vasculitis mimics may be ineffective, even deteriorating. This article presents the utility of CT in the diagnosis and differential diagnosis of vasculitides

CT features of vasculitides based on the 2012 international chapel hill consensus conference revised classification

Energy Technology Data Exchange (ETDEWEB)

Hur, Jee Hye; Chun, Eun Ju; Kim, Hae Young; Kim, Jeong Jae; Lee, Kyung Won [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Kwang, Hyon Joo [Dept. of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Yoo, Jin Young [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of)

2017-09-15

Vasculitis, characterized by inflammation of vessel walls, is comprised of heterogeneous clinicopathological entities, and thus poses a diagnostic challenge. The most widely used approach for classifying vasculitides is based on the International Chapel Hill Consensus Conference (CHCC) nomenclature system. Based on the recently revised CHCC 2012, we propose computed tomography (CT) features of vasculitides and a differential diagnosis based on location and morphological characteristics. Finally, vasculitis mimics should be differentiated, because erroneous application of immunosuppressive drugs on vasculitis mimics may be ineffective, even deteriorating. This article presents the utility of CT in the diagnosis and differential diagnosis of vasculitides.

Use of dynamic images in radiology education: Movies of CT and MRI in the anatomy classroom.

Science.gov (United States)

Jang, Hye Won; Oh, Chang-Seok; Choe, Yeon Hyeon; Jang, Dong Su

2018-04-19

Radiology education is a key component in many preclinical anatomy courses. However, the reported effectiveness of radiology education within such anatomy classrooms has varied. This study was conducted to determine if a novel educational method using dynamic images of movies of computed tomography (CT) and magnetic resonance imaging (MRI) was effective in radiology education during a preclinical anatomy course, aided by clay modeling, specific hand gestures (digit anatomy), and reports from dissection findings uploaded to the anatomy course website (digital reports). Feedback surveys using a five-point Likert scale were administered to better clarify students' opinions regarding their understanding of CT and MRI of anatomical structures, as well as to determine if such preclinical radiology education was helpful in their clinical studies. After completion of the anatomy course taught with dynamic images of CT and MRI, most students demonstrated an adequate understanding of basic CT and MR images. Additionally, students in later clinical years generally believed that their study of radiologic images during the preclinical anatomy course was helpful for their clinical studies and clerkship rotations. Moreover, student scores on imaging anatomy examinations demonstrated meaningful improvements in performance after using dynamic images from movies of CT and MRI. Anat Sci Educ. © 2018 American Association of Anatomists. © 2018 American Association of Anatomists.

Localized thin-section CT with radiomics feature extraction and machine learning to classify early-detected pulmonary nodules from lung cancer screening

Science.gov (United States)

Tu, Shu-Ju; Wang, Chih-Wei; Pan, Kuang-Tse; Wu, Yi-Cheng; Wu, Chen-Te

2018-03-01

Lung cancer screening aims to detect small pulmonary nodules and decrease the mortality rate of those affected. However, studies from large-scale clinical trials of lung cancer screening have shown that the false-positive rate is high and positive predictive value is low. To address these problems, a technical approach is greatly needed for accurate malignancy differentiation among these early-detected nodules. We studied the clinical feasibility of an additional protocol of localized thin-section CT for further assessment on recalled patients from lung cancer screening tests. Our approach of localized thin-section CT was integrated with radiomics features extraction and machine learning classification which was supervised by pathological diagnosis. Localized thin-section CT images of 122 nodules were retrospectively reviewed and 374 radiomics features were extracted. In this study, 48 nodules were benign and 74 malignant. There were nine patients with multiple nodules and four with synchronous multiple malignant nodules. Different machine learning classifiers with a stratified ten-fold cross-validation were used and repeated 100 times to evaluate classification accuracy. Of the image features extracted from the thin-section CT images, 238 (64%) were useful in differentiating between benign and malignant nodules. These useful features include CT density (p  =  0.002 518), sigma (p  =  0.002 781), uniformity (p  =  0.032 41), and entropy (p  =  0.006 685). The highest classification accuracy was 79% by the logistic classifier. The performance metrics of this logistic classification model was 0.80 for the positive predictive value, 0.36 for the false-positive rate, and 0.80 for the area under the receiver operating characteristic curve. Our approach of direct risk classification supervised by the pathological diagnosis with localized thin-section CT and radiomics feature extraction may support clinical physicians in determining

The CT features of recurrent laryngeal nerve paralysis

International Nuclear Information System (INIS)

Wu Bin; Peng Weijun; Gu Yajia; Yang Tianxi; Wang Hongshi

2006-01-01

Objective: To describe the CT appearance of recurrent laryngeal nerve paralysis, discuss the anatomic and pathologic basis of this paralysis, and evaluate CT diagnosis. Methods: 32 cases of recurrent laryngeal nerve paralysis clinical confirmed were analyzed retrospectively. All of these patients had the CT scans from the level of hyoid bone to the upper thorax, the slice and interval are 5 mm. Results: CT findings of recurrent laryngeal nerve paralysis included: oblique of aryepiglottic fold, dislocation of arytenoid cartilage and cricoarytenoid joint, dilation and relaxation of piriform sinus for 27 cases (84.4%); wide and asymmetrical ventricle of larynx for 16 cases (50.0%); asymmetrical and fix of vocal fold for 11 cases (34.4%) et al. Conclusion: The recurrent laryngeal nerve innervate all the intrinsic muscles of the larynx except cricothyroid muscle, paralysis of the nerve leads to atrophy of related muscles. CT scan demonstrate the larynx morphologic changes of recurrent nerve paralysis and is helpful to identify the etiology. (authors)

Gastrointestinal involvement of recurrent renal cell carcinoma: CT findings and clinicpathologic features

Energy Technology Data Exchange (ETDEWEB)

Park, Hyo Jung; Kim, Hyun Jin; Park, Seung Ho; Lee, Jong Seok; Kim, Ah Young [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Ha, Hyun Kwon [Dept. of Radiology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung (Korea, Republic of)

2017-06-15

To retrospectively evaluate the CT findings and clinicopathologic features in patients with gastrointestinal (GI) involvement of recurrent renal cell carcinoma (RCC). The medical records were reviewed for 15 patients with 19 pathologically proven GI tract metastases of RCC. The CT findings were analyzed to determine the involved sites and type of involvement; lesion size, morphology, and contrast enhancement pattern; and occurrence of lymphadenopathy, ascites and other complications. The most common presentation was GI bleeding (66.7%). The average interval between nephrectomy and the detection of GI involvement was 30.4 ± 37.4 months. GI lesions were most commonly found in the ileum (36.8%) and duodenum (31.6%). A distant metastasis (80%) was more common than a direct invasion from metastatic lesions. The mean lesion size was 34.1 ± 15.0 mm. Intraluminal polypoid masses (63.2%) with hyperenhancement (78.9%) and heterogeneous enhancement (63.2%) were the most common findings. No patients had regional lymphadenopathy. Complications occurred in four patients, with one each of bowel obstruction, intussusception, bile duct dilatation, and pancreatic duct dilatation. GI involvement of recurrent RCC could be included in the differential diagnosis of patients with heterogeneous, hyperenhanced intraluminal polypoid masses in the small bowel on CT scans along with a relative paucity of lymphadenopathy.

Can low-dose CT with iterative reconstruction reduce both the radiation dose and the amount of iodine contrast medium in a dynamic CT study of the liver?

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Hiroto; Okada, Masahiro; Hyodo, Tomoko; Hidaka, Syojiro; Kagawa, Yuki; Matsuki, Mitsuru; Tsurusaki, Masakatsu; Murakami, Takamichi, E-mail: murakami@med.kindai.ac.jp

2014-04-15

Purpose: To investigate whether low-dose dynamic CT of the liver with iterative reconstruction can reduce both the radiation dose and the amount of contrast medium. Materials and methods: This study was approved by our institutional review board. 113 patients were randomly assigned to one of two groups. Group A/group B (fifty-eight/fifty-five patients) underwent liver dynamic CT at 120/100 kV, with 0/40% adaptive statistical iterative reconstruction (ASIR), with a contrast dose of 600/480 mg I/kg, respectively. Radiation exposure was estimated based on the manufacturer's phantom data. The enhancement value of the hepatic parenchyma, vessels and the tumor-to-liver contrast of hepatocellular carcinomas (HCCs) were compared between two groups. Two readers independently assessed the CT images of the hepatic parenchyma and HCCs. Results: The mean CT dose indices: 6.38/4.04 mGy, the dose-length products: 194.54/124.57 mGy cm, for group A/group B. The mean enhancement value of the hepatic parenchyma and the tumor-to-liver contrast of HCCs with diameters greater than 1 cm in the post-contrast all phases did not differ significantly between two groups (P > 0.05). The enhancement values of vessels in group B were significantly higher than that in group A in the delayed phases (P < 0.05). Two reader's confidence levels for the hepatic parenchyma in the delayed phases and HCCs did not differ significantly between the groups (P > 0.05). Conclusions: Low-dose dynamic CT with ASIR can reduce both the radiation dose and the amount of contrast medium without image quality degradation, compared to conventional dynamic CT without ASIR.

Comparison of cerebrospinal fluid dynamics studied by computed tomography (CT) and radioisotope (RI) cisternography

International Nuclear Information System (INIS)

Tamaki, N.; Kanazawa, Y.; Asada, M.; Kusunoki, T.; Matsumoto, S.

1978-01-01

CT and RI cisternography were done on 55 cases with normal and abnormal CSF circulation. Of 19 cases in which both studies were done, 14 cases disclosed a good correspondence. The remaining five cases showed no correspondence because of technical failure. Analyzing the results, CT cisternography demonstrates pathology of the CSF dynamics in a more precise and quantitative manner than RI cisternography does. Metrizamide CT cisternography will soon be the most reliable method of investigation for the evaluation of the CSF kinetics. (orig.) [de

A temporal interpolation approach for dynamic reconstruction in perfusion CT

International Nuclear Information System (INIS)

Montes, Pau; Lauritsch, Guenter

2007-01-01

This article presents a dynamic CT reconstruction algorithm for objects with time dependent attenuation coefficient. Projection data acquired over several rotations are interpreted as samples of a continuous signal. Based on this idea, a temporal interpolation approach is proposed which provides the maximum temporal resolution for a given rotational speed of the CT scanner. Interpolation is performed using polynomial splines. The algorithm can be adapted to slow signals, reducing the amount of data acquired and the computational cost. A theoretical analysis of the approximations made by the algorithm is provided. In simulation studies, the temporal interpolation approach is compared with three other dynamic reconstruction algorithms based on linear regression, linear interpolation, and generalized Parker weighting. The presented algorithm exhibits the highest temporal resolution for a given sampling interval. Hence, our approach needs less input data to achieve a certain quality in the reconstruction than the other algorithms discussed or, equivalently, less x-ray exposure and computational complexity. The proposed algorithm additionally allows the possibility of using slow rotating scanners for perfusion imaging purposes

CT, Magnetic Resonance, and {sup 18}F-Fluorodeoxyglucose Positron Emission Tomography/CT Imaging Features of Mucosa-Associated Lymphoid Tissue Lymphoma Involving Medial Rectus Muscle: A Case Report

Energy Technology Data Exchange (ETDEWEB)

Lee, Sang Kwon; Choe, Mi Sun [Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of)

2013-06-15

We report a case of mucosa-associated lymphoid tissue (MALT) lymphoma involving the medial rectus muscle in a 47-year-old man along with CT, MRI, 18 F-fluorodeoxy-glucose positron emission tomography/CT ( 18 F-FDG PET/CT), and pathologic features. The lesion was manifested as a fusiform enlargement isolated to the right medial rectus muscle with involvement of its tendinous insertion. The lesion was isoattenuating to the brain on non-enhanced CT images, showing as isointense to gray matter on fast spin echo T1- and T2-weighted images with fat saturation, and showed homogeneous enhancement on contrast-enhanced CT and MR images. The maximum stan- dardized uptake value on 18 F-FDG PET/CT was 4.9 g/mL. The results of histological and immunohistochemical examinations of the specimen obtained by biopsy of the right medial rectus muscle were consistent with MALT lymphoma. It should be noted that the extraocular muscle (EOM) is a rare location for the involvement of MALT lympho- ma, and MALT lymphoma of the EOM may mimic thyroid orbitopathy.

High-resolution dynamic imaging and quantitative analysis of lung cancer xenografts in nude mice using clinical PET/CT.

Science.gov (United States)

Wang, Ying Yi; Wang, Kai; Xu, Zuo Yu; Song, Yan; Wang, Chu Nan; Zhang, Chong Qing; Sun, Xi Lin; Shen, Bao Zhong

2017-08-08

Considering the general application of dedicated small-animal positron emission tomography/computed tomography is limited, an acceptable alternative in many situations might be clinical PET/CT. To estimate the feasibility of using clinical PET/CT with [F-18]-fluoro-2-deoxy-D-glucose for high-resolution dynamic imaging and quantitative analysis of cancer xenografts in nude mice. Dynamic clinical PET/CT scans were performed on xenografts for 60 min after injection with [F-18]-fluoro-2-deoxy-D-glucose. Scans were reconstructed with or without SharpIR method in two phases. And mice were sacrificed to extracting major organs and tumors, using ex vivo γ-counting as a reference. Strikingly, we observed that the image quality and the correlation between the all quantitive data from clinical PET/CT and the ex vivo counting was better with the SharpIR reconstructions than without. Our data demonstrate that clinical PET/CT scanner with SharpIR reconstruction is a valuable tool for imaging small animals in preclinical cancer research, offering dynamic imaging parameters, good image quality and accurate data quatification.

Low dose dynamic CT myocardial perfusion imaging using a statistical iterative reconstruction method

Energy Technology Data Exchange (ETDEWEB)

Tao, Yinghua [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States); Chen, Guang-Hong [Department of Medical Physics and Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States); Hacker, Timothy A.; Raval, Amish N. [Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53792 (United States); Van Lysel, Michael S.; Speidel, Michael A., E-mail: speidel@wisc.edu [Department of Medical Physics and Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States)

2014-07-15

Purpose: Dynamic CT myocardial perfusion imaging has the potential to provide both functional and anatomical information regarding coronary artery stenosis. However, radiation dose can be potentially high due to repeated scanning of the same region. The purpose of this study is to investigate the use of statistical iterative reconstruction to improve parametric maps of myocardial perfusion derived from a low tube current dynamic CT acquisition. Methods: Four pigs underwent high (500 mA) and low (25 mA) dose dynamic CT myocardial perfusion scans with and without coronary occlusion. To delineate the affected myocardial territory, an N-13 ammonia PET perfusion scan was performed for each animal in each occlusion state. Filtered backprojection (FBP) reconstruction was first applied to all CT data sets. Then, a statistical iterative reconstruction (SIR) method was applied to data sets acquired at low dose. Image voxel noise was matched between the low dose SIR and high dose FBP reconstructions. CT perfusion maps were compared among the low dose FBP, low dose SIR and high dose FBP reconstructions. Numerical simulations of a dynamic CT scan at high and low dose (20:1 ratio) were performed to quantitatively evaluate SIR and FBP performance in terms of flow map accuracy, precision, dose efficiency, and spatial resolution. Results: Forin vivo studies, the 500 mA FBP maps gave −88.4%, −96.0%, −76.7%, and −65.8% flow change in the occluded anterior region compared to the open-coronary scans (four animals). The percent changes in the 25 mA SIR maps were in good agreement, measuring −94.7%, −81.6%, −84.0%, and −72.2%. The 25 mA FBP maps gave unreliable flow measurements due to streaks caused by photon starvation (percent changes of +137.4%, +71.0%, −11.8%, and −3.5%). Agreement between 25 mA SIR and 500 mA FBP global flow was −9.7%, 8.8%, −3.1%, and 26.4%. The average variability of flow measurements in a nonoccluded region was 16.3%, 24.1%, and 937

Low dose dynamic CT myocardial perfusion imaging using a statistical iterative reconstruction method

International Nuclear Information System (INIS)

Tao, Yinghua; Chen, Guang-Hong; Hacker, Timothy A.; Raval, Amish N.; Van Lysel, Michael S.; Speidel, Michael A.

2014-01-01

Purpose: Dynamic CT myocardial perfusion imaging has the potential to provide both functional and anatomical information regarding coronary artery stenosis. However, radiation dose can be potentially high due to repeated scanning of the same region. The purpose of this study is to investigate the use of statistical iterative reconstruction to improve parametric maps of myocardial perfusion derived from a low tube current dynamic CT acquisition. Methods: Four pigs underwent high (500 mA) and low (25 mA) dose dynamic CT myocardial perfusion scans with and without coronary occlusion. To delineate the affected myocardial territory, an N-13 ammonia PET perfusion scan was performed for each animal in each occlusion state. Filtered backprojection (FBP) reconstruction was first applied to all CT data sets. Then, a statistical iterative reconstruction (SIR) method was applied to data sets acquired at low dose. Image voxel noise was matched between the low dose SIR and high dose FBP reconstructions. CT perfusion maps were compared among the low dose FBP, low dose SIR and high dose FBP reconstructions. Numerical simulations of a dynamic CT scan at high and low dose (20:1 ratio) were performed to quantitatively evaluate SIR and FBP performance in terms of flow map accuracy, precision, dose efficiency, and spatial resolution. Results: Forin vivo studies, the 500 mA FBP maps gave −88.4%, −96.0%, −76.7%, and −65.8% flow change in the occluded anterior region compared to the open-coronary scans (four animals). The percent changes in the 25 mA SIR maps were in good agreement, measuring −94.7%, −81.6%, −84.0%, and −72.2%. The 25 mA FBP maps gave unreliable flow measurements due to streaks caused by photon starvation (percent changes of +137.4%, +71.0%, −11.8%, and −3.5%). Agreement between 25 mA SIR and 500 mA FBP global flow was −9.7%, 8.8%, −3.1%, and 26.4%. The average variability of flow measurements in a nonoccluded region was 16.3%, 24.1%, and 937

Primary pulmonary low-grade angiosarcoma characterized by mismatch between {sup 18}F-FDG FET and dynamic contrast-enhanced CT

Energy Technology Data Exchange (ETDEWEB)

KIm, Eun Young; Lee, Ho Yun; Han, Joung Ho; Choi, Joon Young [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2015-10-15

We report a rare case of primary pulmonary low-grade angiosarcoma on dynamic contrast-enhanced CT and {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT imaging. A 38-year-old, asymptomatic woman was hospitalized because of an abnormality on chest radiography. A dynamic contrast-enhanced chest CT showed a 1.2 cm-sized irregular-margined nodule with strong and persistent enhancement in the right lower lobe. The lesion had low metabolic activity on an {sup 18}F-FDG PET/CT scan. The patient underwent a wedge resection for the lesion, and pathology revealed a primary pulmonary low-grade angiosarcoma.

Machine Learning Algorithms Utilizing Quantitative CT Features May Predict Eventual Onset of Bronchiolitis Obliterans Syndrome After Lung Transplantation.

Science.gov (United States)

Barbosa, Eduardo J Mortani; Lanclus, Maarten; Vos, Wim; Van Holsbeke, Cedric; De Backer, William; De Backer, Jan; Lee, James

2018-02-19

Long-term survival after lung transplantation (LTx) is limited by bronchiolitis obliterans syndrome (BOS), defined as a sustained decline in forced expiratory volume in the first second (FEV 1 ) not explained by other causes. We assessed whether machine learning (ML) utilizing quantitative computed tomography (qCT) metrics can predict eventual development of BOS. Paired inspiratory-expiratory CT scans of 71 patients who underwent LTx were analyzed retrospectively (BOS [n = 41] versus non-BOS [n = 30]), using at least two different time points. The BOS cohort experienced a reduction in FEV 1 of >10% compared to baseline FEV 1 post LTx. Multifactor analysis correlated declining FEV 1 with qCT features linked to acute inflammation or BOS onset. Student t test and ML were applied on baseline qCT features to identify lung transplant patients at baseline that eventually developed BOS. The FEV 1 decline in the BOS cohort correlated with an increase in the lung volume (P = .027) and in the central airway volume at functional residual capacity (P = .018), not observed in non-BOS patients, whereas the non-BOS cohort experienced a decrease in the central airway volume at total lung capacity with declining FEV 1 (P = .039). Twenty-three baseline qCT parameters could significantly distinguish between non-BOS patients and eventual BOS developers (P machine), we could identify BOS developers at baseline with an accuracy of 85%, using only three qCT parameters. ML utilizing qCT could discern distinct mechanisms driving FEV 1 decline in BOS and non-BOS LTx patients and predict eventual onset of BOS. This approach may become useful to optimize management of LTx patients. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

CT features of second branchial cleft cysts: emphasis on the locations of lesions

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Han, Deok Sub; Kim, Byong Geun; Park, Byung Ran; Kim, Se Jong; Ko, Kang Seok; Oh, Jong Sub [Kwangju Christian Hospital, Gwangju (Korea, Republic of); Seo, Jeong Jin [Chonnam Univ. Medical School, Gwangju (Korea, Republic of)

1994-11-15

The purpose of this study was to evaluate the CT features of second branchial cleft cysts. We retrospectively analyzed the computed tomographic images in nine cases of second branchial cleft cyst which was confirmed pathologically. Emphasis was on localization of the masses to fascial spaces as defined by the deep cervical fasica. In all nine cases, the lesions were located in the submandibular and carotid spaces. Among these cases, six(67%) had simultaneous involvement of the other contiguous spaces, such as anterior and posterior cervical spaces. All cases had round or oval, unilocular, cystic masses with partial or complete rim enhancement. In eight cases(89%), smooth and thin walls were observed. In one case, thick wall and septations were noted. No definite calcifications were noted in all cases. The internal contents of cystic masses showed relatively homogeneous appearance, and CT number ranged from 20 to 35.2 Hounsfield unit(HU)(mean, 28.4HU). CT diagnosis of second branchial cleft cyst would be easily obtained from recognition of frequent simultaneous involvement of the other contiguous spaces, along with a typical location and characteristic morphology.

CT features of second branchial cleft cysts: emphasis on the locations of lesions

International Nuclear Information System (INIS)

Han, Deok Sub; Kim, Byong Geun; Park, Byung Ran; Kim, Se Jong; Ko, Kang Seok; Oh, Jong Sub; Seo, Jeong Jin

1994-01-01

The purpose of this study was to evaluate the CT features of second branchial cleft cysts. We retrospectively analyzed the computed tomographic images in nine cases of second branchial cleft cyst which was confirmed pathologically. Emphasis was on localization of the masses to fascial spaces as defined by the deep cervical fasica. In all nine cases, the lesions were located in the submandibular and carotid spaces. Among these cases, six(67%) had simultaneous involvement of the other contiguous spaces, such as anterior and posterior cervical spaces. All cases had round or oval, unilocular, cystic masses with partial or complete rim enhancement. In eight cases(89%), smooth and thin walls were observed. In one case, thick wall and septations were noted. No definite calcifications were noted in all cases. The internal contents of cystic masses showed relatively homogeneous appearance, and CT number ranged from 20 to 35.2 Hounsfield unit(HU)(mean, 28.4HU). CT diagnosis of second branchial cleft cyst would be easily obtained from recognition of frequent simultaneous involvement of the other contiguous spaces, along with a typical location and characteristic morphology

Characterizing, measuring, and utilizing the resolution of CT imagery for improved quantification of fine-scale features

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Ketcham, Richard A., E-mail: ketcham@jsg.utexas.edu; Hildebrandt, Jordan

2014-04-01

Quantitative results extracted from computed tomographic (CT) data sets should be the same across resolutions and between different instruments and laboratory groups. Despite the proliferation of scanners and data processing methods and tools, and scientific studies utilizing them, relatively little emphasis has been given to ensuring that these results are comparable or reproducible. This issue is particularly pertinent when the features being imaged and measured are of the same order size as data voxels, as is often the case with fracture apertures, pore throats, and cell walls. We have created a tool that facilitates quantification of the spatial resolution of CT data via its point-spread function (PSF), in which the user draws a traverse across a sharp interface between two materials and a Gaussian PSF is fitted to the blurring across that interface. Geometric corrections account for voxel shape and the angle of the traverse to the interface, which does not need to be orthogonal. We use the tool to investigate a series of grid phantoms scanned at varying conditions and observe how the PSF varies within and between slices. The PSF increases with increasing radial distance within slices, and can increase tangentially with increasing radial distance in CT data sets acquired with relatively few projections. The PSF between CT slices is similar to that within slices when a 2-D detector is used, but is much sharper when the data are acquired one slice at a time with a collimated linear detector array. The capability described here can be used not only to calibrate processing algorithms that use deconvolution operations, but it can also help evaluate scans on a routine basis within and between CT research groups, and with respect to the features within the imagery that are being measured.

(68)Ga-PSMA-11 dynamic PET/CT imaging in biochemical relapse of prostate cancer.

Science.gov (United States)

Sachpekidis, C; Eder, M; Kopka, K; Mier, W; Hadaschik, B A; Haberkorn, U; Dimitrakopoulou-Strauss, A

2016-07-01

We aim to investigate the pharmacokinetics and distribution of the recently clinically introduced radioligand (68)Ga-PSMA-11 in men with recurrent prostate cancer (PC) by means of dynamic and whole-body PET/CT. The correlation between PSA levels and (68)Ga-PSMA-11 PET parameters is also investigated. 31 patients with biochemical failure after primary PC treatment with curative intent (median age 71.0 years) were enrolled in the analysis. The median PSA value was 2.0 ng/mL (range = 0.1 - 130.0 ng/mL) and the median Gleason score was 7 (range = 5 - 9). 8/31 (25.8 %) of the included patients had a PSA value dynamic PET/CT (dPET/CT) scanning (60 min) of the pelvis and lower abdomen as well as whole-body PET/CT with (68)Ga-PSMA-11. dPET/CT assessment was based on qualitative evaluation, SUV calculation, and quantitative analysis based on a two-tissue compartment model and a non-compartmental approach leading to the extraction of fractal dimension (FD). 22/31 patients (71.0 %) were (68)Ga-PSMA-11-positive, while 9/31 (29.0 %) patients were (68)Ga-PSMA-11-negative. The median PSA value in the (68)Ga-PSMA-11-positive group was significantly higher (median = 2.35 ng/mL; range = 0.19 - 130.0 ng/mL) than in the (68)Ga-PSMA-11-negative group (median value: 0.34 ng/mL; range = 0.10 - 4.20 ng/mL). A total of 76 lesions were semi-quantitatively evaluated. PC recurrence-associated lesions demonstrated a mean SUVaverage = 12.4 (median = 9.0; range = 2.2 - 84.5) and mean SUVmax = 18.8 (median = 14.1; range = 3.1 - 120.3). Dynamic PET/CT studies of the pelvis revealed the following mean values for the PC recurrence-suspicious lesions: K1 = 0.26, k3 = 0.30, influx = 0.14 and FD = 1.24. Time-activity curves derived from PC-recurrence indicative lesions revealed an increasing (68)Ga-PSMA-11 accumulation during dynamic PET acquisition. Correlation analysis revealed a moderate, but significant, correlation between PSA

Practical CT technology and techniques

International Nuclear Information System (INIS)

Berland, L.L.

1987-01-01

This handbook equips both radiologists and radiologists in training with a thorough working knowledge of the mechanisms and processes of computed tomography (CT) image generation, the common causes of image artifacts, and useful examination protocols for each area of the body. The author explains the fundamental technological principles of CT, focusing on those concepts crucial to successful CT examinations. The first part of the book succinctly reviews the fundamentals of CT technology. It begins with a methodical introduction to key principles of X-ray physics and technology, in which topics such as the modulation transfer function, magnification, and the X-ray tube are discussed in understandable, nonmathematical terms. The author then explains the basic technology of CT scanners, the principles of scan projection radiography, and the essential rules for radiation dosage determination and radiation protection. Careful attention is given to selectable scan factors in both routine and dynamic scanning, as well as to the processes involved in image creation and refinement and the chief determinants of image quality. Basic and specialized program features and the technology of image display, recording, and storage are also thoroughly described

Dynamic multislice helical CT of maxillomandibular lesions. Distinction of ameloblastomas from other cystic lesions

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Tozaki, Mitsuhiro; Hayashi, Katsuhiko; Fukuda, Kunihiko [Jikei Univ., Tokyo (Japan). School of Medicine

2001-10-01

The purpose of this study was to evaluate the clinical usefulness of dynamic multislice helical CT in differentiating ameloblastoma from other cystic lesions in cases of maxillomandibular cystic lesions. The study included 32 patients with maxillomandibular cystic lesions (ameloblastoma [n=6], myxofibroma [n=1], odontogenic keratocyst [n=3], dentigerous cyst [n=11], radicular cyst [n=11], and paradental cyst [n=2]). Dynamic study was performed before and 30 sec, and 90 sec after intravenous contrast medium administration. CT density values and percentage of density increase were calculated at 30 and 90 sec. In five cases of ameloblastoma, a rapidly enhancing area was detected within the cystic lesions at 30 sec, while no apparent rapid enhancement was seen in the other cystic lesions. Three cysts showed gradual enhancement in the marginal area at 90 sec. Comparing ameloblastoma and other kinds of cysts, we found significant differences in the percentage of density increase at 30 sec (p<0.01) and 90 sec (p<0.05). Dynamic multislice helical CT is useful in the diagnosis of cystic lesions of the maxillomandibular region, especially in the detection of neovascularities in ameloblastoma. (author)

Dynamic multislice helical CT of maxillomandibular lesions. Distinction of ameloblastomas from other cystic lesions

International Nuclear Information System (INIS)

Tozaki, Mitsuhiro; Hayashi, Katsuhiko; Fukuda, Kunihiko

2001-01-01

The purpose of this study was to evaluate the clinical usefulness of dynamic multislice helical CT in differentiating ameloblastoma from other cystic lesions in cases of maxillomandibular cystic lesions. The study included 32 patients with maxillomandibular cystic lesions (ameloblastoma [n=6], myxofibroma [n=1], odontogenic keratocyst [n=3], dentigerous cyst [n=11], radicular cyst [n=11], and paradental cyst [n=2]). Dynamic study was performed before and 30 sec, and 90 sec after intravenous contrast medium administration. CT density values and percentage of density increase were calculated at 30 and 90 sec. In five cases of ameloblastoma, a rapidly enhancing area was detected within the cystic lesions at 30 sec, while no apparent rapid enhancement was seen in the other cystic lesions. Three cysts showed gradual enhancement in the marginal area at 90 sec. Comparing ameloblastoma and other kinds of cysts, we found significant differences in the percentage of density increase at 30 sec (p<0.01) and 90 sec (p<0.05). Dynamic multislice helical CT is useful in the diagnosis of cystic lesions of the maxillomandibular region, especially in the detection of neovascularities in ameloblastoma. (author)

SU-D-207B-01: Radiomics Feature Reproducibility From Repeat CT Scans of Patients with Rectal Cancer

Energy Technology Data Exchange (ETDEWEB)

Hu, P; Wang, J; Zhong, H; Zhou, Z; Shen, L; Hu, W; Zhang, Z [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China)

2016-06-15

Purpose: To evaluate the reproducibility of radiomics features by repeating computed tomographic (CT) scans in rectal cancer. To choose stable radiomics features for rectal cancer. Methods: 40 rectal cancer patients were enrolled in this study, each of whom underwent two CT scans within average 8.7 days (5 days to 17 days), before any treatment was delivered. The rectal gross tumor volume (GTV) was distinguished and segmented by an experienced oncologist in both CTs. Totally, more than 2000 radiomics features were defined in this study, which were divided into four groups (I: GLCM, II: GLRLM III: Wavelet GLCM and IV: Wavelet GLRLM). For each group, five types of features were extracted (Max slice: features from the largest slice of target images, Max value: features from all slices of target images and choose the maximum value, Min value: minimum value of features for all slices, Average value: average value of features for all slices, Matrix sum: all slices of target images translate into GLCM and GLRLM matrices and superpose all matrices, then extract features from the superposed matrix). Meanwhile a LOG (Laplace of Gauss) filter with different parameters was applied to these images. Concordance correlation coefficients (CCC) and inter-class correlation coefficients (ICC) were calculated to assess the reproducibility. Results: 403 radiomics features were extracted from each type of patients’ medical images. Features of average type are the most reproducible. Different filters have little effect for radiomics features. For the average type features, 253 out of 403 features (62.8%) showed high reproducibility (ICC≥0.8), 133 out of 403 features (33.0%) showed medium reproducibility (0.8≥ICC≥0.5) and 17 out of 403 features (4.2%) showed low reproducibility (ICC≥0.5). Conclusion: The average type radiomics features are the most stable features in rectal cancer. Further analysis of these features of rectal cancer can be warranted for treatment monitoring and

Subprosthetic Pannus after Aortic Valve Replacement Surgery: Cardiac CT Findings and Clinical Features.

Science.gov (United States)

Han, Kichang; Yang, Dong Hyun; Shin, So Youn; Kim, Namkug; Kang, Joon-Won; Kim, Dae-Hee; Song, Jong-Min; Kang, Duk-Hyun; Song, Jae-Kwan; Kim, Joon Bum; Jung, Sung-Ho; Choo, Suk Jung; Chung, Cheol Hyun; Lee, Jae Won; Lim, Tae-Hwan

2015-09-01

To investigate the cardiac computed tomographic (CT) findings and clinical implications of subprosthetic pannus in patients who have undergone aortic valve replacement. The institutional review board approved this retrospective study, and the need to obtain written informed consent was waived. From April 2011 to March 2012, 88 patients (mean age, 63 years; 45 men) with a prosthetic aortic valve who underwent cardiac CT were retrospectively selected. Dynamic cardiac CT images were analyzed by using a multiplanar reformatted technique. The presence or absence of subprosthetic pannus and its extent were evaluated at cardiac CT. The geometric orifice area and the effective orifice area of each prosthetic valve were measured to enable analysis of the pannus encroachment ratio in the systolic phase. Hemodynamic parameters at echocardiography, including mean transprosthetic pressure gradient (MTPG), were compared between patients with and those without pannus. The encroachment ratio and the MTPG were correlated by using the Spearman test to evaluate the relationship between the two variables. Seventeen patients (19%) had subprosthetic pannus at cardiac CT. In patients with subprosthetic pannus, MTPG, peak pressure gradient, transvalvular peak velocity, and left ventricular ejection fraction (LVEF) were significantly higher than in patients without pannus (MTPG: 28.1 mm Hg ± 19.8 [standard deviation] vs 14.0 mm Hg ± 6.5, P = .004; peak pressure gradient: 53.1 mm Hg ± 38.4 vs 26.1 mm Hg ± 11.4, P = .004; transvalvular peak velocity: 3.3 m/sec ± 1.3 vs 2.5 m/sec ± 0.5; and LVEF: 64.7% ± 7.4 vs 56.8% ± 10.5, P = .004). A high MTPG (≥40 mm Hg) was observed in four patients at echocardiography, and subprosthetic panni were identified at CT in all four patients. In patients with increased MTPGs, the encroachment ratio by subprosthetic pannus at CT was significantly higher than that in patients with MTPGs of less than 40 mm Hg (42.7 ± 13.3 vs 7.6 ± 3, P = .012

Persistent topological features of dynamical systems

Energy Technology Data Exchange (ETDEWEB)

Maletić, Slobodan, E-mail: slobodan@hitsz.edu.cn [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen (China); Institute of Nuclear Sciences Vinča, University of Belgrade, Belgrade (Serbia); Zhao, Yi, E-mail: zhao.yi@hitsz.edu.cn [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen (China); Rajković, Milan, E-mail: milanr@vinca.rs [Institute of Nuclear Sciences Vinča, University of Belgrade, Belgrade (Serbia)

2016-05-15

Inspired by an early work of Muldoon et al., Physica D 65, 1–16 (1993), we present a general method for constructing simplicial complex from observed time series of dynamical systems based on the delay coordinate reconstruction procedure. The obtained simplicial complex preserves all pertinent topological features of the reconstructed phase space, and it may be analyzed from topological, combinatorial, and algebraic aspects. In focus of this study is the computation of homology of the invariant set of some well known dynamical systems that display chaotic behavior. Persistent homology of simplicial complex and its relationship with the embedding dimensions are examined by studying the lifetime of topological features and topological noise. The consistency of topological properties for different dynamic regimes and embedding dimensions is examined. The obtained results shed new light on the topological properties of the reconstructed phase space and open up new possibilities for application of advanced topological methods. The method presented here may be used as a generic method for constructing simplicial complex from a scalar time series that has a number of advantages compared to the mapping of the same time series to a complex network.

A case of severe acute pancreatitis with near total pancreatic necrosis diagnosed by dynamic CT scanning

International Nuclear Information System (INIS)

Takeda, Kazunori; Kakugawa, Yoichiro; Amikura, Katsumi; Miyagawa, Kikuo; Matsuno, Seiki; Sato, Toshio

1987-01-01

A 42 year-old woman with severe acute pancreatitis had drainage of the pancreatic bed, cholecystostomy and jejunostomy on admission, but symptoms were not improved. Fourteen days after admission, clinical sepsis and septisemia were recognized. Dynamic CT scanning of the pancreas showed near total pancreatic necrosis. Symptoms were improved after necrosectomy of the pancreas and debridement of the peripancreatic necrotic tissue were performed. Our experience suggests the usefulness of dynamic CT scanning for detection of pancreatic necrosis in severe acute pancreatitis. (author)

WE-E-17A-05: Complementary Prognostic Value of CT and 18F-FDG PET Non-Small Cell Lung Cancer Tumor Heterogeneity Features Quantified Through Texture Analysis

Energy Technology Data Exchange (ETDEWEB)

Desseroit, M; Cheze Le Rest, C; Tixier, F [CHU Poitiers Poitiers (France); INSERM LaTIM UMR 1101, Brest (France); Majdoub, M; Visvikis, D; Hatt, M [INSERM LaTIM UMR 1101, Brest (France); Guillevin, R; Perdrisot, R [CHU Poitiers Poitiers (France)

2014-06-15

Purpose: Previous studies have shown that CT or 18F-FDG PET intratumor heterogeneity features computed using texture analysis may have prognostic value in Non-Small Cell Lung Cancer (NSCLC), but have been mostly investigated separately. The purpose of this study was to evaluate the potential added value with respect to prognosis regarding the combination of non-enhanced CT and 18F-FDG PET heterogeneity textural features on primary NSCLC tumors. Methods: One hundred patients with non-metastatic NSCLC (stage I–III), treated with surgery and/or (chemo)radiotherapy, that underwent staging 18F-FDG PET/CT images, were retrospectively included. Morphological tumor volumes were semi-automatically delineated on non-enhanced CT using 3D SlicerTM. Metabolically active tumor volumes (MATV) were automatically delineated on PET using the Fuzzy Locally Adaptive Bayesian (FLAB) method. Intratumoral tissue density and FDG uptake heterogeneities were quantified using texture parameters calculated from co-occurrence, difference, and run-length matrices. In addition to these textural features, first order histogram-derived metrics were computed on the whole morphological CT tumor volume, as well as on sub-volumes corresponding to fine, medium or coarse textures determined through various levels of LoG-filtering. Association with survival regarding all extracted features was assessed using Cox regression for both univariate and multivariate analysis. Results: Several PET and CT heterogeneity features were prognostic factors of overall survival in the univariate analysis. CT histogram-derived kurtosis and uniformity, as well as Low Grey-level High Run Emphasis (LGHRE), and PET local entropy were independent prognostic factors. Combined with stage and MATV, they led to a powerful prognostic model (p<0.0001), with median survival of 49 vs. 12.6 months and a hazard ratio of 3.5. Conclusion: Intratumoral heterogeneity quantified through textural features extracted from both CT and FDG PET

Early Dynamic 68Ga-DOTA-D-Phe1-Tyr3-Octreotide PET/CT in Patients With Hepatic Metastases of Neuroendocrine Tumors.

Science.gov (United States)

Sänger, Philipp Wilhelm; Freesmeyer, Martin

2016-06-01

Whole-body PET with Ga-DOTA-D-Phe-Tyr-octreotide (Ga-DOTATOC) and contrast-enhanced CT (ceCT) are considered a standard for the staging of neuroendocrine tumors (NETs). This study sought to verify whether early dynamic (ed) Ga-DOTATOC PET/CT can reliably detect liver metastases of NETs (hypervascular, nonhypervascular; positive or negative for somatostatin receptors) and to verify if the receptor positivity has a significant impact on the detection of tumor hypervascularization. Twenty-seven patients with NET were studied by ceCT and standard whole-body PET according to established Ga-DOTATOC protocols. In addition, edPET data were obtained by continuous scanning during the first 300 seconds after bolus injections of the radiotracer. Early dynamic PET required an additional low-dose, native CT image of the liver for the purpose of attenuation correction. Time-activity and time-contrast curves were obtained, the latter being calculated by the difference between tumor and reference regions. Early dynamic PET/CT proved comparable with ceCT in readily identifying hypervascular lesions, irrespective of the receptor status, with activities rising within 16 to 40 seconds. Early dynamic PET/CT also readily identified nonhypervascular, receptor-positive lesions. Positive image contrasts were obtained for hypervascular, receptor-positive lesions, whereas early negative contrasts were obtained for nonhypervascular, receptor-negative lesions. The high image contrast of hypervascular NET metastases in early arterial phases suggests that edPET/CT can become a useful alternative in patients with contraindications to ceCT. The high density of somatostatin receptors did not seem to interfere with the detection of the lesion's hypervascularization.

Hepatic blood flow mapping by dynamic CT method in liver diseases

International Nuclear Information System (INIS)

Sugano, Shigeo; Mizuyosi, Hideo; Okajima, Tsugio; Ishii, Kouji; Abei, Tohru; Machida, Keiichi

1986-01-01

Two parameters of dynamic CT, peak time (PT) and first moment (M1), were compared among healthy control, chronic hepatitis (CH) and liver cirrhosis (LC). The means of PT and M1 in each 9 (3 x 3) pixels on a slice of hepatic CT were computed and converted to gray spots by gray scale, so that deep gray represented high values and light gray low values of these parameters. The distribution of these gray spots in each pixels was depicted on the slice as a blood flow mapping, and it was compared among the groups. In normal control, dynamic CT showed the shortest PT and deep gray spots were distributed diffusely in the slice. In CH, where PT was longer than control, lighter gray spots were diffusely seen. LC had the longest PT and its mapping showed mottles of light gray and black, the latter indicating the presence of spots with scanty blood flow, scattering throughout the slice. The mapping of M1 gave almost the same picture as PT for each group, revieling that the disappearring time of the media in CH and LC was impaired in the same manner as in PT. This method of hepatic blood flow mapping was thought to be useful to add evidences for the understanding of abnormal blood flow in liver diseases. (author)

Gastric stromal tumor: two-phase dynamic CT findings with water as oral contrast agents

International Nuclear Information System (INIS)

Lee, Se Hyo; Cho, June Sik; Shin, Kyung Sook; Jeong, Ki Ho; Park, Jin Yong; Yu, Ho Jun; Kim, Young Min; Jeon, Kwang Jin

2000-01-01

To evaluate two-phase dynamic CT with water as oral contrast agents in the CT diagnosis of gastric stromal tumors. We retrospectively reviewed the CT findings in 21 patients with pathologically proven gastric stromal tumors. Six were found to be benign, twelve were malignant, and there were three cases of STUMP (stromal tumor uncertain malignant potential). Two-phase dynamic CT scans with water as oral contrast agents were obtained 60-70 secs (portal phase) and 3 mins (equilibrium phase) after the start of IV contrast administration. We determined the size, growth pattern, and enhancement pattern of the tumors and overlying mucosa, the presence or absence of ulceration and necrosis, tumor extent, and lymph nod and distant metastasis. The CT and pathologic findings were correlated. All six benign tumors and three STUMP were less than 5.5 cm in size, and during the portal phase showed round endogastric masses with highly enhanced, intact overlying mucosa. Twelve malignant tumors were 4.5-15.5 cm in size (mean, 11.5 cm); an endogastric mass was seen in three cases, an exogastric mass in one, and a mixed pattern in eight. On portal phase images the tumors were not significantly enhanced, but highly enhanced feeding vessels were noted in five larger tumors (greater than 10 cm). All 12 malignant tumors showed ulceration and necrosis, and interruption of overlying mucosa was clearly seen during the portal phase. We were readily able to evaluate tumor extent during this phase, and in ten malignant tumors there was no invasion of adjacent organs. Seven malignant tumors showed air density within their necrotic portion (p less than 0.05). On equilibrium phase images, all malignant tumors showed heterogeneous enhancement due to necrosis, and poorly enhanced overlying mucosa. Dynamic CT during the portal phase with water as oral contrast agents was useful for depicting the submucosal origin of gastric stromal tumors and for evaluating the extent of malignant stromal tumors. Our

A feature alignment score for online cone-beam CT-based image-guided radiotherapy for prostate cancer.

Science.gov (United States)

Hargrave, Catriona; Deegan, Timothy; Poulsen, Michael; Bednarz, Tomasz; Harden, Fiona; Mengersen, Kerrie

2018-05-17

To develop a method for scoring online cone-beam CT (CBCT)-to-planning CT image feature alignment to inform prostate image-guided radiotherapy (IGRT) decision-making. The feasibility of incorporating volume variation metric thresholds predictive of delivering planned dose into weighted functions, was investigated. Radiation therapists and radiation oncologists participated in workshops where they reviewed prostate CBCT-IGRT case examples and completed a paper-based survey of image feature matching practices. For 36 prostate cancer patients, one daily CBCT was retrospectively contoured then registered with their plan to simulate delivered dose if (a) no online setup corrections and (b) online image alignment and setup corrections, were performed. Survey results were used to select variables for inclusion in classification and regression tree (CART) and boosted regression trees (BRT) modeling of volume variation metric thresholds predictive of delivering planned dose to the prostate, proximal seminal vesicles (PSV), bladder, and rectum. Weighted functions incorporating the CART and BRT results were used to calculate a score of individual tumor and organ at risk image feature alignment (FAS TV _ OAR ). Scaled and weighted FAS TV _ OAR were then used to calculate a score of overall treatment compliance (FAS global ) for a given CBCT-planning CT registration. The FAS TV _ OAR were assessed for sensitivity, specificity, and predictive power. FAS global thresholds indicative of high, medium, or low overall treatment plan compliance were determined using coefficients from multiple linear regression analysis. Thirty-two participants completed the prostate CBCT-IGRT survey. While responses demonstrated consensus of practice for preferential ranking of planning CT and CBCT match features in the presence of deformation and rotation, variation existed in the specified thresholds for observed volume differences requiring patient repositioning or repeat bladder and bowel

Dynamic contrast-enhanced CT appearances of the intraductal papillary neoplasms of the bile duct

International Nuclear Information System (INIS)

Song Fengxiang; Zhou Jianjun; Zeng Mengsu; Zhou Kangrong; Ding Yuqin; He Deming; Shi Yuxin; Zhou Jun

2013-01-01

Objective: To analyze the dynamic contrast-enhanced CT appearances of intraductal papillary neoplasms of the bile duct and improve its diagnostic accuracy. Methods: Sixteen patients with intraductal papillary neoplasms of the bile duct confirmed histopathologically after surgical operation underwent dynamic contrast-enhanced multi-detector row CT scans. All imaging data were reviewed and analyzed retrospectively in correlation with surgical and pathological findings. CT values of 38 well-visualized lesions in 12 of the 16 patients at the pre-contrast phase, arterial phase and venous phase were measured. Four of the 12 patients with 17 lesions had benign tumors, and 8 of the 12 patients with 21 lesions had malignant tumors. Comparisons of CT values at the three phases between the two groups were carried out using independent sample t test. The bile CT values were measured in these 12 cases, 40 normal volunteers, and 40 subjects with bile duct stones, and the Wilcoxon signed-rank test was applied to compare the bile CT values between tumor group and the normal group and between tumor group and the bile duct stone group. The diameters of the bile ducts proximal to and distal to tumors were also measured, and Fisher exact method was carried to analyze the data. Results: Lesions located at the left lobe in 8 out of the 16 patients, the right lobe in 1 case, both the left and right lobes in 1 case, the hepatic hilum in 1 case, the common bile duct in 3 cases, and both the right lobe and the common bile duct in 2 cases. Eleven lesions appeared as papillary masses, 3 as flat masses, 1 as mixed papillary and flat masses. In one case, tumor mass could not be definitely visualized, and only dilated bile ducts and stones were demonstrated. The mean CT values of the benign tumors were (25.8 ± 8.0), (37.7 ± 10.3) and (51.7 ± 17.1) HU respectively at pre-contrast phase, arterial phase, and venous phase, and the malignant tumors were (38.4 ± 10.2), (56.6 ± 18.0) and (68.4 �

Pathological manifestation of difference in washout pattern of adrenal hyperplasia on dynamic CT

International Nuclear Information System (INIS)

Nishie, Akihiro; Asayama, Yoshiki; Ishigami, Kousei

2014-01-01

The relationship between the washout pattern and constituent cell in adrenal hyperplasia (AH) has not been fully investigated. The purpose of this study was to elucidate the radiological or pathological factors determining the washout pattern of AH on dynamic CT. Ten patients with 14 surgically proven AHs were enrolled. Dynamic CT was scanned before (pre-contrast image) and 60 seconds (early phase) and 240 seconds (delayed phase) after administration of iodine contrast. The absolute percentage washout (APW) of each nodular lesion was calculated using the following formula: APW(%)=(TAearly-TAdelay) / (TAearly-TApre)×100, when TApre, TAearly and TAdelay were defined as tumour attenuation values of pre-contrast, early and delayed phases, respectively. Pathologically, the clear cell ratio (CCR) constituting each nodular lesion was qualitatively assessed. Regression analysis was performed to evaluate a correlation between each pair of CCR, TApre, (TAearly-TAdelay) and APW. There was a significant correlation between each pair of CCR, TApre and APW. CCR decreased as TApre increased (r=0.81, P<0.001). APW increased as CCR decreased r=0.80, P<0.001) or as TApre increased (r=0.74, P<0.01). The key factors of washout pattern of AH on dynamic CT were CCR and TApre. The difference in constituent cell was associated with variability in APW of AH.

Dual-energy computed tomography for the assessment of early treatment effects of regorafenib in a preclinical tumor model: comparison with dynamic contrast-enhanced CT and conventional contrast-enhanced single-energy CT

International Nuclear Information System (INIS)

Knobloch, Gesine; Hamm, Bernd; Jost, Gregor; Pietsch, Hubertus; Huppertz, Alexander

2014-01-01

The potential diagnostic value of dual-energy computed tomography (DE-CT) compared to dynamic contrast-enhanced CT (DCE-CT) and conventional contrast-enhanced CT (CE-CT) in the assessment of early regorafenib treatment effects was evaluated in a preclinical setting. A rat GS9L glioma model was examined with contrast-enhanced dynamic DE-CT measurements (80 kV/140 kV) for 4 min before and on days 1 and 4 after the start of daily regorafenib or placebo treatment. Tumour time-density curves (0-240 s, 80 kV), DE-CT (60 s) derived iodine maps and the DCE-CT (0-30 s, 80 kV) based parameters blood flow (BF), blood volume (BV) and permeability (PMB) were calculated and compared to conventional CE-CT (60 s, 80 kV). The regorafenib group showed a marked decrease in the tumour time-density curve, a significantly lower iodine concentration and a significantly lower PMB on day 1 and 4 compared to baseline, which was not observed for the placebo group. CE-CT showed a significant decrease in tumour density on day 4 but not on day 1. The DE-CT-derived iodine concentrations correlated with PMB and BV but not with BF. DE-CT allows early treatment monitoring, which correlates with DCE-CT. Superior performance was observed compared to single-energy CE-CT. circle Regorafenib treatment response was evaluated by CT in a rat tumour model. (orig.)

Dual-energy computed tomography for the assessment of early treatment effects of regorafenib in a preclinical tumor model: comparison with dynamic contrast-enhanced CT and conventional contrast-enhanced single-energy CT

Energy Technology Data Exchange (ETDEWEB)

Knobloch, Gesine; Hamm, Bernd [Charite - Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany); Jost, Gregor; Pietsch, Hubertus [Bayer Healthcare, MR and CT Contrast Media Research, Berlin (Germany); Huppertz, Alexander [Imaging Science Institute Charite - Siemens, Berlin (Germany)

2014-08-15

The potential diagnostic value of dual-energy computed tomography (DE-CT) compared to dynamic contrast-enhanced CT (DCE-CT) and conventional contrast-enhanced CT (CE-CT) in the assessment of early regorafenib treatment effects was evaluated in a preclinical setting. A rat GS9L glioma model was examined with contrast-enhanced dynamic DE-CT measurements (80 kV/140 kV) for 4 min before and on days 1 and 4 after the start of daily regorafenib or placebo treatment. Tumour time-density curves (0-240 s, 80 kV), DE-CT (60 s) derived iodine maps and the DCE-CT (0-30 s, 80 kV) based parameters blood flow (BF), blood volume (BV) and permeability (PMB) were calculated and compared to conventional CE-CT (60 s, 80 kV). The regorafenib group showed a marked decrease in the tumour time-density curve, a significantly lower iodine concentration and a significantly lower PMB on day 1 and 4 compared to baseline, which was not observed for the placebo group. CE-CT showed a significant decrease in tumour density on day 4 but not on day 1. The DE-CT-derived iodine concentrations correlated with PMB and BV but not with BF. DE-CT allows early treatment monitoring, which correlates with DCE-CT. Superior performance was observed compared to single-energy CE-CT. circle Regorafenib treatment response was evaluated by CT in a rat tumour model. (orig.)

Differential CT features between malignant mesothelioma and pleural metastasis from lung cancer or extra thoracic primary tumor mimicking malignant mesothelioma

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Lee, Sung Il; Ryu, Young Hoon; Lee, Kwang Hun; Choe, Kyu Ok; Kim, Sang Jin [College of Medicine, Yonsei University, Seoul (Korea, Republic of)

2000-01-01

To evaluate the differential CT features found among malignant mesothelioma and pleural metastasis from lung cancer and from extra-thoracic primary tumor which on CT mimic malignant mesothelioma. Forty-four patients who on chest CT scans showed pleural thickening suggesting malignant pleural disease and in whom this condition was pathologically confirmed were included in this study. On the basis of their pathologically proven primary disease (malignant mesothelioma (n=3D14), pleural metastasis of lung cancer (n=3D18), extra thoracic primary tumor (n=3D12). They were divided into three groups. Cases of lung which on CT showed a primary lung nodule or endobronchial mass with pleural lesion, or manifested only pleural effusion, were excluded. The following eight CT features were retrospectively analyzed: (1) configuration of pleural lesion (type I, single or multiple separate nodules, type II, localized flat pleural thickening, type III, diffuse flat pleural thickening; type IV, type III with pleural nodules superimposed; type V, mass filling the hemithorax), (2) the presence of pleural effusion, (3) chest wall or rib invasion, (4) the involvement of a major fissure, (5) extra-pleural fat proliferation, (6) calcified plaque, (7) metastatic lymph nodes, (8) metastatic lung modules. In malignant mesothelioma, type IV (8/14) or II (4/14) pleural thickening was relatively frequent. Pleural metastasis of lung cancer favored type IV (8/18) or I (6/18) pleural thickening, while pleural metastasis from extrathoracic primary tumor showed a variable thickening configuration, except type V. Pleural metastasis from lung cancer and extrapleural primary tumor more frequently showed type I configuration than did malignant mesothelioma, and there were significant differences among the three groups. Fissural involvement, on the other hand, was significantly more frequent in malignant mesothelioma than in pleural metastasis from lung cancer or extrapleural primary tumor. Metastatic

Separation of left and right lungs using 3D information of sequential CT images and a guided dynamic programming algorithm

Science.gov (United States)

Park, Sang Cheol; Leader, Joseph Ken; Tan, Jun; Lee, Guee Sang; Kim, Soo Hyung; Na, In Seop; Zheng, Bin

2011-01-01

Objective this article presents a new computerized scheme that aims to accurately and robustly separate left and right lungs on CT examinations. Methods we developed and tested a method to separate the left and right lungs using sequential CT information and a guided dynamic programming algorithm using adaptively and automatically selected start point and end point with especially severe and multiple connections. Results the scheme successfully identified and separated all 827 connections on the total 4034 CT images in an independent testing dataset of CT examinations. The proposed scheme separated multiple connections regardless of their locations, and the guided dynamic programming algorithm reduced the computation time to approximately 4.6% in comparison with the traditional dynamic programming and avoided the permeation of the separation boundary into normal lung tissue. Conclusions The proposed method is able to robustly and accurately disconnect all connections between left and right lungs and the guided dynamic programming algorithm is able to remove redundant processing. PMID:21412104

Combined early dynamic (18)F-FDG PET/CT and conventional whole-body (18)F-FDG PET/CT provide one-stop imaging for detecting hepatocellular carcinoma.

Science.gov (United States)

Wang, Shao-Bo; Wu, Hu-Bing; Wang, Quan-Shi; Zhou, Wen-Lan; Tian, Ying; Li, Hong-Sheng; Ji, Yun-Hai; Lv, Liang

2015-06-01

It is widely accepted that conventional (18)F-FDG PET/CT (whole-body static (18)F-FDG PET/CT, WB (18)F-FDG PET/CT) has a low detection rate for hepatocellular carcinoma (HCC). We prospectively assessed the role of early dynamic (18)F-FDG PET/CT (ED (18)F-FDG PET/CT) and WB (18)F-FDG PET/CT in detecting HCC, and we quantified the added value of ED (18)F-FDG PET/CT to WB (18)F-FDG PET/CT. Twenty-two patients with 37 HCC tumors (HCCs) who underwent both a liver ED (18)F-FDG PET/CT (performed simultaneously with a 5.5 MBq/kg (18)F-FDG bolus injection and continued for 240 s) and a WB (18)F-FDG PET/CT were enrolled in the study. The WB (18)F-FDG PET/CT and ED (18)F-FDG PET/CT scans were positive in 56.7% (21/37) and 78.4% (29/37) HCCs, respectively (PPET/CT in conjunction with WB (18)F-FDG PET/CT (one-stop (18)F-FDG PET/CT) improved the positive detection rates of WB and ED (18)F-FDG PET/CT alone from 56.7% and 78.4% to 91.9% (34/37) (P0.05, respectively). One-stop (18)F-FDG PET/CT appears to be useful to improve WB (18)F-FDG PET/CT for HCC detection. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Determination of single-kidney glomerular filtration rate (GFR) with CT urography versus renal dynamic imaging Gates method

Energy Technology Data Exchange (ETDEWEB)

You, Shan [Hebei North University, Department of Graduate, Zhangjiakou City, Hebei Province (China); Ma, XianWu; Zhang, ChangZhu; Li, Qiang [Qiqihar Chinese Medicine Hospital, Department of Radiology, Qigihar City, Heilongjiang Province (China); Shi, WenWei; Zhang, Jing; Yuan, XiaoDong [The 309th Hospital of Chinese People' s Liberation Army, Department of Radiology, Beijing (China)

2018-03-15

To present a single-kidney CT-GFR measurement and compare it with the renal dynamic imaging Gates-GFR. Thirty-six patients with hydronephrosis referred for CT urography and 99mTc-DTPA renal dynamic imaging were prospectively included. Informed consent was obtained from all patients. The CT urography protocol included non-contrast, nephrographic, and excretory phase imaging. The total CT-GFR was calculated by dividing the CT number increments of the total urinary system between the nephrographic and excretory phase by the products of iodine concentration in the aorta and the elapsed time, then multiplied by (1- Haematocrit). The total CT-GFR was then split into single-kidney CT-GFR by a left and right kidney proportionality factor. The results were compared with single-kidney Gates-GFR by using paired t-test, correlation analysis, and Bland-Altman plots. Paired difference between single-kidney CT-GFR (45.02 ± 13.91) and single-kidney Gates-GFR (51.21 ± 14.76) was 6.19 ± 5.63 ml/min, p<0.001, demonstrating 12.1% systematic underestimation with ±11.03 ml/min (±21.5%) measurement deviation. A good correlation was revealed between both measurements (r=0.87, p<0.001). The proposed single-kidney CT-GFR correlates and agrees well with the reference standard despite a systematic underestimation, therefore it could be a one-stop-shop for evaluating urinary tract morphology and split renal function. (orig.)

Determination of single-kidney glomerular filtration rate (GFR) with CT urography versus renal dynamic imaging Gates method

International Nuclear Information System (INIS)

You, Shan; Ma, XianWu; Zhang, ChangZhu; Li, Qiang; Shi, WenWei; Zhang, Jing; Yuan, XiaoDong

2018-01-01

To present a single-kidney CT-GFR measurement and compare it with the renal dynamic imaging Gates-GFR. Thirty-six patients with hydronephrosis referred for CT urography and 99mTc-DTPA renal dynamic imaging were prospectively included. Informed consent was obtained from all patients. The CT urography protocol included non-contrast, nephrographic, and excretory phase imaging. The total CT-GFR was calculated by dividing the CT number increments of the total urinary system between the nephrographic and excretory phase by the products of iodine concentration in the aorta and the elapsed time, then multiplied by (1- Haematocrit). The total CT-GFR was then split into single-kidney CT-GFR by a left and right kidney proportionality factor. The results were compared with single-kidney Gates-GFR by using paired t-test, correlation analysis, and Bland-Altman plots. Paired difference between single-kidney CT-GFR (45.02 ± 13.91) and single-kidney Gates-GFR (51.21 ± 14.76) was 6.19 ± 5.63 ml/min, p<0.001, demonstrating 12.1% systematic underestimation with ±11.03 ml/min (±21.5%) measurement deviation. A good correlation was revealed between both measurements (r=0.87, p<0.001). The proposed single-kidney CT-GFR correlates and agrees well with the reference standard despite a systematic underestimation, therefore it could be a one-stop-shop for evaluating urinary tract morphology and split renal function. (orig.)

Static and dynamic CT imaging of the cervical spine in patients with rheumatoid arthritis

Energy Technology Data Exchange (ETDEWEB)

Soederman, Tomas; Shalabi, Adel; Sundin, Anders [Uppsala University Hospital, Department of Radiology, Uppsala (Sweden); Olerud, Claes; Alavi, Kamran [Uppsala University Hospital, Department of Orthopedic Surgery, Uppsala (Sweden)

2014-09-18

To compare CR with CT (static and dynamic) to evaluate upper spine instability and to determine if CT in flexion adds value compared to MR imaging in neutral position to assess compression of the subarachnoid space and of the spinal cord. Twenty-one consecutive patients with atlantoaxial subluxation due to rheumatoid arthritis planned for atlantoaxial fusion were included. CT and MRI were performed with the neck in the neutral position and CT also in flexion. CR in neutral position and flexion were obtained in all patients except for one subject who underwent examination in flexion and extension. CR and CT measurements of atlantoaxial subluxation correlated but were larger by CR than CT in flexion, however, the degree of vertical dislocation was similar with both techniques irrespective of the position of the neck. Cervical motion was larger at CR than at CT. The spinal cord compression was significantly worse at CT obtained in the flexed position as compared to MR imaging in the neutral position. Functional CR remains the primary imaging method but CT in the flexed position might be useful in the preoperative imaging work-up, as subarachnoid space involvement may be an indicator for the development of neurologic dysfunction. (orig.)

MO-DE-207B-04: Impact of Reconstruction Field of View On Radiomics Features in Computed Tomography (CT) Using a Texture Phantom

Energy Technology Data Exchange (ETDEWEB)

Shafiq ul Hassan, M; Zhang, G; Oliver, J; Moros, E [H Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Department of Physics, University of South Florida (United States); Latifi, K; Hunt, D; Guzman, R; Balagurunathan, Y; Gillies, R [H Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Mackin, D; Court, L [UT MD Anderson Cancer Center, Houston, TX (United States)

2016-06-15

Purpose: To investigate the impact of reconstruction Field of View on Radiomics features in computed tomography (CT) using a texture phantom. Methods: A rectangular Credence Cartridge Radiomics (CCR) phantom, composed of 10 different cartridges, was scanned on four different CT scanners from two manufacturers. A pre-defined scanning protocol was adopted for consistency. The slice thickness and reconstruction interval of 1.5 mm was used on all scanners. The reconstruction FOV was varied to result a voxel size ranging from 0.38 to 0.98 mm. A spherical region of interest (ROI) was contoured on the shredded rubber cartridge from CCR phantom CT scans. Ninety three Radiomics features were extracted from ROI using an in-house program. These include 10 shape, 22 intensity, 26 GLCM, 11 GLZSM, 11 RLM, 5 NGTDM and 8 fractal dimensional features. To evaluate the Interscanner variability across three scanners, a coefficient of variation (COV) was calculated for each feature group. Each group was further classified according to the COV by calculating the percentage of features in each of the following categories: COV≤ 5%, between 5 and 10% and ≥ 10%. Results: Shape features were the most robust, as expected, because of the spherical contouring of ROI. Intensity features were the second most robust with 54.5 to 64% of features with COV < 5%. GLCM features ranged from 31 to 35% for the same category. RLM features were sensitive to specific scanner and 5% variability was 9 to 54%. Almost all GLZM and NGTDM features showed COV ≥10% among the scanners. The dependence of fractal dimensions features on FOV was not consistent across different scanners. Conclusion: We concluded that reconstruction FOV greatly influence Radiomics features. The GLZSM and NGTDM are highly sensitive to FOV. funded in part by Grant NIH/NCI R01CA190105-01.

TU-C-12A-09: Modeling Pathologic Response of Locally Advanced Esophageal Cancer to Chemo-Radiotherapy Using Quantitative PET/CT Features, Clinical Parameters and Demographics

International Nuclear Information System (INIS)

Zhang, H; Chen, W; Kligerman, S; D’Souza, W; Suntharalingam, M; Lu, W; Tan, S; Kim, G

2014-01-01

Purpose: To develop predictive models using quantitative PET/CT features for the evaluation of tumor response to neoadjuvant chemo-radiotherapy (CRT) in patients with locally advanced esophageal cancer. Methods: This study included 20 patients who underwent tri-modality therapy (CRT + surgery) and had 18 F-FDG PET/CT scans before initiation of CRT and 4-6 weeks after completion of CRT but prior to surgery. Four groups of tumor features were examined: (1) conventional PET/CT response measures (SUVmax, tumor diameter, etc.); (2) clinical parameters (TNM stage, histology, etc.) and demographics; (3) spatial-temporal PET features, which characterize tumor SUV intensity distribution, spatial patterns, geometry, and associated changes resulting from CRT; and (4) all features combined. An optimal feature set was identified with recursive feature selection and cross-validations. Support vector machine (SVM) and logistic regression (LR) models were constructed for prediction of pathologic tumor response to CRT, using cross-validations to avoid model over-fitting. Prediction accuracy was assessed via area under the receiver operating characteristic curve (AUC), and precision was evaluated via confidence intervals (CIs) of AUC. Results: When applied to the 4 groups of tumor features, the LR model achieved AUCs (95% CI) of 0.57 (0.10), 0.73 (0.07), 0.90 (0.06), and 0.90 (0.06). The SVM model achieved AUCs (95% CI) of 0.56 (0.07), 0.60 (0.06), 0.94 (0.02), and 1.00 (no misclassifications). Using spatial-temporal PET features combined with conventional PET/CT measures and clinical parameters, the SVM model achieved very high accuracy (AUC 1.00) and precision (no misclassifications), significantly better than using conventional PET/CT measures or clinical parameters and demographics alone. For groups with a large number of tumor features (groups 3 and 4), the SVM model achieved significantly higher accuracy than the LR model. Conclusion: The SVM model using all features including

Improvement of temporal and dynamic subtraction images on abdominal CT using 3D global image matching and nonlinear image warping techniques

International Nuclear Information System (INIS)

Okumura, E; Sanada, S; Suzuki, M; Takemura, A; Matsui, O

2007-01-01

Accurate registration of the corresponding non-enhanced and arterial-phase CT images is necessary to create temporal and dynamic subtraction images for the enhancement of subtle abnormalities. However, respiratory movement causes misregistration at the periphery of the liver. To reduce these misregistration errors, we developed a temporal and dynamic subtraction technique to enhance small HCC by 3D global matching and nonlinear image warping techniques. The study population consisted of 21 patients with HCC. Using the 3D global matching and nonlinear image warping technique, we registered current and previous arterial-phase CT images or current non-enhanced and arterial-phase CT images obtained in the same position. The temporal subtraction image was obtained by subtracting the previous arterial-phase CT image from the warped current arterial-phase CT image. The dynamic subtraction image was obtained by the subtraction of the current non-enhanced CT image from the warped current arterial-phase CT image. The percentage of fair or superior temporal subtraction images increased from 52.4% to 95.2% using the new technique, while on the dynamic subtraction images, the percentage increased from 66.6% to 95.2%. The new subtraction technique may facilitate the diagnosis of subtle HCC based on the superior ability of these subtraction images to show nodular and/or ring enhancement

CT features of renal infarction

International Nuclear Information System (INIS)

Suzer, Okan; Shirkhoda, Ali; Jafri, S. Zafar; Madrazo, Beatrice L.; Bis, Kostaki G.; Mastromatteo, James F.

2002-01-01

Purpose: To demonstrate the different patterns of renal infarction to avoid pitfalls. To present 'flip-flop enhancement' pattern in renal infarction. Materials and methods: Retrospective review of a total of 41 renal infarction in 37 patients were done. These patients underwent initial CT and the diagnosis of renal infarction was confirmed with either follow up CT or at surgery. Results: Twenty-three patients had wedge-shaped focal infarcts, nine patients had global and five patients had multifocal infarcts of the kidneys. Cortical rim sign was seen predominantly with global infarcts. In five patients, a 'flip-flop enhancement' pattern was observed. In two patients, planned renal biopsies due to tumefactive renal lesions were cancelled because of 'flip-flop enhancement' pattern on follow up CTs. Conclusion: Although most of our cases were straightforward for the diagnosis of renal infarction, cases with tumefactive lesions and global infarctions without the well-known cortical rim sign were particularly challenging. We describe a new sign, flip-flop enhancement pattern, which we believe solidified the diagnosis of renal infarction in five of our cases. The authors recommend further investigations for association of flip-flop enhancement and renal infarction

Leiomyoma of the sinonasal cavity: CT and MRI findings

International Nuclear Information System (INIS)

Yang, B.T.; Wang, Z.C.; Xian, J.F.; Hao, D.P.; Chen, Q.H.

2009-01-01

Aim: To determine the computed tomography (CT) and magnetic resonance imaging (MRI) features of leiomyoma of the sinonasal cavity. Materials and methods: Six patients with histology-proven leiomyomas in the sinonasal cavity were retrospectively reviewed. All six patients underwent CT and three patients also underwent MRI. The following imaging features were reviewed: size, margin, CT attenuation, MRI signal intensity, and lesion extent. In addition, the time-intensity curve (TIC) of dynamic contrast-enhanced (DCE) MRI and diffusion-weighted imaging (DWI) were analysed in two patients. Results: All leiomyomas had well-defined margins. The mean size was 36 mm (range 20-51 mm). On unenhanced CT, the lesions appeared isodense to cerebral grey matter in four (67%) and slightly hypodense in two (33%) patients. Leiomyomas appeared isointense On T1-weighted imaging (WI) and slightly hyperintense on T2WI in three patients. The lesions showed moderate contrast enhancement. Two patients underwent DCE MRI, and the TIC showed a rapidly enhancing and slow washout pattern. The mean apparent diffusion coefficient (ADC) value were 1.66 x 10 -3 mm 2 /s and 1.78 x 10 -3 mm 2 /s for the two lesions, respectively. Conclusions: Well-defined, homogeneous, expansile masses without bony erosion are typical features of leiomyoma. Althrough rare, this entity should be included in the differential diagnosis of benign tumours in this region.

Leiomyoma of the sinonasal cavity: CT and MRI findings

Energy Technology Data Exchange (ETDEWEB)

Yang, B.T., E-mail: cjr.yangbentao@vip.163.co [Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing (China); Wang, Z.C.; Xian, J.F.; Hao, D.P.; Chen, Q.H. [Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing (China)

2009-12-15

Aim: To determine the computed tomography (CT) and magnetic resonance imaging (MRI) features of leiomyoma of the sinonasal cavity. Materials and methods: Six patients with histology-proven leiomyomas in the sinonasal cavity were retrospectively reviewed. All six patients underwent CT and three patients also underwent MRI. The following imaging features were reviewed: size, margin, CT attenuation, MRI signal intensity, and lesion extent. In addition, the time-intensity curve (TIC) of dynamic contrast-enhanced (DCE) MRI and diffusion-weighted imaging (DWI) were analysed in two patients. Results: All leiomyomas had well-defined margins. The mean size was 36 mm (range 20-51 mm). On unenhanced CT, the lesions appeared isodense to cerebral grey matter in four (67%) and slightly hypodense in two (33%) patients. Leiomyomas appeared isointense On T1-weighted imaging (WI) and slightly hyperintense on T2WI in three patients. The lesions showed moderate contrast enhancement. Two patients underwent DCE MRI, and the TIC showed a rapidly enhancing and slow washout pattern. The mean apparent diffusion coefficient (ADC) value were 1.66 x 10{sup -3} mm{sup 2}/s and 1.78 x 10{sup -3} mm{sup 2}/s for the two lesions, respectively. Conclusions: Well-defined, homogeneous, expansile masses without bony erosion are typical features of leiomyoma. Althrough rare, this entity should be included in the differential diagnosis of benign tumours in this region.

SU-F-R-07: Radiomics of CT Features and Associations and Correlation with Outcomes Following Lung SBRT

Energy Technology Data Exchange (ETDEWEB)

Schreibmann, E; Iwinski Sutter, A; Whitaker, D; Switchenko, J; Elder, E; Higgins, K; Patel, P [Department of Radiation Oncology and Winship Cancer Institute of Emory University Atlanta, GA (United States)

2016-06-15

Objective: To investigate the prognostic significance of image gradients and in predicting clinical outcomes in a patients with non-small cell lung cancer treated with stereotactic body radiotherapy (SBRT) on 71 patients with 83 treated lesions. Methods: The records of patients treated with lung SBRT were retrospectively reviewed. When applicable, SBRT target volumes were modified to exclude any overlap with pleura, chestwall, or mediastinum. The ITK software package was utilized to generate quantitative measures of image intensity, inhomogeneity, shape morphology and first and second-order CT textures. Multivariate and univariate models containing CT features were generated to assess associations with clinicopathologic factors. Results: On univariate analysis, tumor size (HR 0.54, p=0.045) sumHU (HR 0.31, p=0.044) and short run grey level emphasis STD (HR 0.22, p=0.019) were associated with regional failure-free survival; meanHU (HR 0.30, p=0.035), long run emphasis (HR 0.21, p=0.011) and long run low grey level emphasis (HR 0.14, p=0.005) was associated with distant failure-free survival (DFFS). No features were significant on multivariate modeling however long run low grey level emphasis had a hazard ratio of 0.12 (p=0.061) for DFFS. Adenocarcinoma and squamous cell carcinoma differed with respect to long run emphasis STD (p=0.024), short run low grey level emphasis STD (p<0.001), and long run low grey level emphasis STD (p=0.024). Multivariate modeling of texture features associated with tumor histology was used to estimate histologies of 18 lesions treated without histologic confirmation. Of these, MVA suggested the same histology as a prior metachronous lung malignancy in 3/7 patients. Conclusion: Extracting radiomics features on clinical datasets was feasible with the ITK package with minimal effort to identify pre-treatment quantitative CT features with prognostic factors for distant control after lung SBRT.

{sup 68}Ga-PSMA-11 dynamic PET/CT imaging in biochemical relapse of prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Sachpekidis, C. [German Cancer Research Center (DKFZ), Clinical Cooperation Unit Nuclear Medicine, Heidelberg (Germany); German Cancer Research Center, Medical PET Group-Biological Imaging, Clinical Cooperation Unit Nuclear Medicine, Heidelberg (Germany); Eder, M. [German Cancer Research Center (DKFZ), Division of Radiopharmaceutical Chemistry, Heidelberg (Germany); Kopka, K. [German Cancer Research Center (DKFZ), Division of Radiopharmaceutical Chemistry, Heidelberg (Germany); German Cancer Consortium (DKTK), Heidelberg (Germany); Mier, W. [University of Heidelberg, Division of Nuclear Medicine, Heidelberg (Germany); Hadaschik, B.A. [University Hospital Heidelberg, Department of Urology, Heidelberg (Germany); Haberkorn, U. [German Cancer Research Center (DKFZ), Clinical Cooperation Unit Nuclear Medicine, Heidelberg (Germany); German Cancer Consortium (DKTK), Heidelberg (Germany); University of Heidelberg, Division of Nuclear Medicine, Heidelberg (Germany); Dimitrakopoulou-Strauss, A. [German Cancer Research Center (DKFZ), Clinical Cooperation Unit Nuclear Medicine, Heidelberg (Germany)

2016-07-15

We aim to investigate the pharmacokinetics and distribution of the recently clinically introduced radioligand {sup 68}Ga-PSMA-11 in men with recurrent prostate cancer (PC) by means of dynamic and whole-body PET/CT. The correlation between PSA levels and {sup 68}Ga-PSMA-11 PET parameters is also investigated. 31 patients with biochemical failure after primary PC treatment with curative intent (median age 71.0 years) were enrolled in the analysis. The median PSA value was 2.0 ng/mL (range = 0.1 - 130.0 ng/mL) and the median Gleason score was 7 (range = 5 - 9). 8/31 (25.8 %) of the included patients had a PSA value < 0.5 ng/ml. All patients underwent dynamic PET/CT (dPET/CT) scanning (60 min) of the pelvis and lower abdomen as well as whole-body PET/CT with {sup 68}Ga-PSMA-11. dPET/CT assessment was based on qualitative evaluation, SUV calculation, and quantitative analysis based on a two-tissue compartment model and a non-compartmental approach leading to the extraction of fractal dimension (FD). 22/31 patients (71.0 %) were {sup 68}Ga-PSMA-11-positive, while 9/31 (29.0 %) patients were {sup 68}Ga-PSMA-11-negative. The median PSA value in the {sup 68}Ga-PSMA-11-positive group was significantly higher (median = 2.35 ng/mL; range = 0.19 - 130.0 ng/mL) than in the {sup 68}Ga-PSMA-11-negative group (median value: 0.34 ng/mL; range = 0.10 - 4.20 ng/mL). A total of 76 lesions were semi-quantitatively evaluated. PC recurrence-associated lesions demonstrated a mean SUV{sub average} = 12.4 (median = 9.0; range = 2.2 - 84.5) and mean SUV{sub max} = 18.8 (median = 14.1; range = 3.1 - 120.3). Dynamic PET/CT studies of the pelvis revealed the following mean values for the PC recurrence-suspicious lesions: K{sub 1} = 0.26, k{sub 3} = 0.30, influx = 0.14 and FD = 1.24. Time-activity curves derived from PC-recurrence indicative lesions revealed an increasing {sup 68}Ga-PSMA-11 accumulation during dynamic PET acquisition. Correlation analysis revealed a moderate, but significant

Assessment of Lymph Nodes and Prostate Status Using Early Dynamic Curves with (18)F-Choline PET/CT in Prostate Cancer.

Science.gov (United States)

Mathieu, Cédric; Ferrer, Ludovic; Carlier, Thomas; Colombié, Mathilde; Rusu, Daniela; Kraeber-Bodéré, Françoise; Campion, Loic; Rousseau, Caroline

2015-01-01

Dynamic image acquisition with (18)F-Choline [fluorocholine (FCH)] PET/CT in prostate cancer is mostly used to overcome the bladder repletion, which could obstruct the loco-regional analysis. The aim of our study was to analyze early dynamic FCH acquisitions to define pelvic lymph node or prostate pathological status. Retrospective analysis was performed on 39 patients for initial staging (n = 18), or after initial treatment (n = 21). Patients underwent 10-min dynamic acquisitions centered on the pelvis, after injection of 3-4 MBq/kg of FCH. Whole-body images were acquired about 1 h after injection using a PET/CT GE Discovery LS (GE-LS) or Siemens Biograph mCT (mCT). Maximum and mean SUV according to time were measured on nodal and prostatic lesions. SUVmean was corrected for partial volume effect (PVEC) with suitable recovery coefficients. The status of each lesion was based on histological results or patient follow-up (>6 months). A Mann-Whitney test and ANOVA were used to compare mean and receiver operating characteristic (ROC) curve analysis. The median PSA was 8.46 ng/mL and the median Gleason score was 3 + 4. Ninety-two lesions (43 lymph nodes and 49 prostate lesions) were analyzed, including 63 malignant lesions. In early dynamic acquisitions, the maximum and mean SUV were significantly higher, respectively, on mCT and GE-LS, in malignant versus benign lesions (p dynamic imaging using PET/CT FCH allowed prostate cancer detection in situations where proof of malignancy is difficult to obtain.

Diagnosis of small hepatocellular carcinoma by incremental dynamic CT

International Nuclear Information System (INIS)

Uchida, Masafumi; Kumabe, Tsutomu; Edamitsu, Osamu

1993-01-01

Thirty cases of pathologically confirmed small hepatocellular carcinoma were examined by Incremental Dynamic CT (ICT). ICT scanned the whole liver with single-breath-hold technique; therefore, effective early contrast enhancement could be obtained for diagnosis. Among the 30 tumors, 26 were detected. The detection rate was 87%. A high detection rate was obtained in tumors more than 20 mm in diameter. Twenty-two of 26 tumors could be diagnosed correctly. ICT examination was useful for detection of small hepatocellular carcinoma. (author)

Alveolar architecture of clear cell renal carcinomas (≤5.0 cm) show high attenuation on dynamic CT scanning

International Nuclear Information System (INIS)

Fujimoto, Hiroyuki; Wakao, Fumihiko; Moriyama, Noriyuki; Tobisu, Kenichi; Kakizoe, Tadao; Sakamoto, Michiie

1999-01-01

To establish the correlation between tumor appearance on CT and tumor histology in renal cell carcinomas. The density and attenuation patterns of 96 renal cell carcinomas, each ≤5 cm in greatest diameter, were studied by non-enhanced CT and early and late after bolus injection of contrast medium using dynamic CT. The density and attenuation patterns and pathological maps of each tumor were individually correlated. High attenuated areas were present in 72 of the 96 tumors on early enhanced dynamic CT scanning. All 72 high attenuated areas were of the clear cell renal cell carcinoma and had alveolar architecture. The remaining 24 tumors that did not demonstrate high attenuated foci on early enhanced scanning included three clear cell, nine granular cell, six papillary, five chromophobe and one collecting duct type. With respect to tumor architecture, all clear cell tumors of alveolar architecture demonstrated high attenuation on early enhanced scanning. Clear cell renal cell carcinomas of alveolar architecture show high attenuation on early enhanced dynamic CT scanning. A larger number of patients are indispensable to obtaining clear results. However, these findings seem to be an important clue to the diagnosis of renal cell carcinomas as having an alveolar structure. (author)

Dynamic CT perfusion imaging of the myocardium: a technical note on improvement of image quality.

Directory of Open Access Journals (Sweden)

Daniela Muenzel

Full Text Available OBJECTIVE: To improve image and diagnostic quality in dynamic CT myocardial perfusion imaging (MPI by using motion compensation and a spatio-temporal filter. METHODS: Dynamic CT MPI was performed using a 256-slice multidetector computed tomography scanner (MDCT. Data from two different patients-with and without myocardial perfusion defects-were evaluated to illustrate potential improvements for MPI (institutional review board approved. Three datasets for each patient were generated: (i original data (ii motion compensated data and (iii motion compensated data with spatio-temporal filtering performed. In addition to the visual assessment of the tomographic slices, noise and contrast-to-noise-ratio (CNR were measured for all data. Perfusion analysis was performed using time-density curves with regions-of-interest (ROI placed in normal and hypoperfused myocardium. Precision in definition of normal and hypoperfused areas was determined in corresponding coloured perfusion maps. RESULTS: The use of motion compensation followed by spatio-temporal filtering resulted in better alignment of the cardiac volumes over time leading to a more consistent perfusion quantification and improved detection of the extend of perfusion defects. Additionally image noise was reduced by 78.5%, with CNR improvements by a factor of 4.7. The average effective radiation dose estimate was 7.1±1.1 mSv. CONCLUSION: The use of motion compensation and spatio-temporal smoothing will result in improved quantification of dynamic CT MPI using a latest generation CT scanner.

Evaluation of dynamic enhanced CT scanning in the differentiation of adrenal lipid-poor adenomas with metastases

International Nuclear Information System (INIS)

Fang Xiangming; Hu Chunhong; Hu Xiaoyun; Chen Hongwei; Wu Liyuan; Zou Xinnong; Qian Pingyan

2006-01-01

Objective: To evaluate dynamic enhanced CT in differentiating adrenal metastases from adrenal lipid-poor adenomas(ALPA). Methods: Both plain and dynamic enhanced CT scanning was performed in 9 metastases with 13 masses and 28 lipid-poor adenoma with 30 masses. The types of time-density curve according to peak time(PT) and relative washout percentage(Washr) besides shape, size, margin, internal structure, surrounding status and enhanced pattern of each lesion were measuerd and compared between the two groups of metastases and ALPA. Results: There is difference between metastases and ALPA in the aspects of shape, density, neighboring structure and the type of enhancement. The type of TDC of matastases was characterized by fast-washin and fast-washout, which was quite differed from the type of TDC of ALPA characterized by fast-washin and slow-washout. According to this, the sensitiveity and specificity for differentiating metastases from ALPA were 96.7%, 92.3%. Conclusion: The types of TDC of dynamic enhanced CT is of great value in differentiating metastases from ALPA. (authors)

TH-E-17A-01: Internal Respiratory Surrogate for 4D CT Using Fourier Transform and Anatomical Features

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Hui, C; Suh, Y; Robertson, D; Pan, T; Das, P; Crane, C; Beddar, S [MD Anderson Cancer Center, Houston, TX (United States)

2014-06-15

Purpose: To develop a novel algorithm to generate internal respiratory signals for sorting of four-dimensional (4D) computed tomography (CT) images. Methods: The proposed algorithm extracted multiple time resolved features as potential respiratory signals. These features were taken from the 4D CT images and its Fourier transformed space. Several low-frequency locations in the Fourier space and selected anatomical features from the images were used as potential respiratory signals. A clustering algorithm was then used to search for the group of appropriate potential respiratory signals. The chosen signals were then normalized and averaged to form the final internal respiratory signal. Performance of the algorithm was tested in 50 4D CT data sets and results were compared with external signals from the real-time position management (RPM) system. Results: In almost all cases, the proposed algorithm generated internal respiratory signals that visibly matched the external respiratory signals from the RPM system. On average, the end inspiration times calculated by the proposed algorithm were within 0.1 s of those given by the RPM system. Less than 3% of the calculated end inspiration times were more than one time frame away from those given by the RPM system. In 3 out of the 50 cases, the proposed algorithm generated internal respiratory signals that were significantly smoother than the RPM signals. In these cases, images sorted using the internal respiratory signals showed fewer artifacts in locations corresponding to the discrepancy in the internal and external respiratory signals. Conclusion: We developed a robust algorithm that generates internal respiratory signals from 4D CT images. In some cases, it even showed the potential to outperform the RPM system. The proposed algorithm is completely automatic and generally takes less than 2 min to process. It can be easily implemented into the clinic and can potentially replace the use of external surrogates.

TH-E-17A-01: Internal Respiratory Surrogate for 4D CT Using Fourier Transform and Anatomical Features

International Nuclear Information System (INIS)

Hui, C; Suh, Y; Robertson, D; Pan, T; Das, P; Crane, C; Beddar, S

2014-01-01

Purpose: To develop a novel algorithm to generate internal respiratory signals for sorting of four-dimensional (4D) computed tomography (CT) images. Methods: The proposed algorithm extracted multiple time resolved features as potential respiratory signals. These features were taken from the 4D CT images and its Fourier transformed space. Several low-frequency locations in the Fourier space and selected anatomical features from the images were used as potential respiratory signals. A clustering algorithm was then used to search for the group of appropriate potential respiratory signals. The chosen signals were then normalized and averaged to form the final internal respiratory signal. Performance of the algorithm was tested in 50 4D CT data sets and results were compared with external signals from the real-time position management (RPM) system. Results: In almost all cases, the proposed algorithm generated internal respiratory signals that visibly matched the external respiratory signals from the RPM system. On average, the end inspiration times calculated by the proposed algorithm were within 0.1 s of those given by the RPM system. Less than 3% of the calculated end inspiration times were more than one time frame away from those given by the RPM system. In 3 out of the 50 cases, the proposed algorithm generated internal respiratory signals that were significantly smoother than the RPM signals. In these cases, images sorted using the internal respiratory signals showed fewer artifacts in locations corresponding to the discrepancy in the internal and external respiratory signals. Conclusion: We developed a robust algorithm that generates internal respiratory signals from 4D CT images. In some cases, it even showed the potential to outperform the RPM system. The proposed algorithm is completely automatic and generally takes less than 2 min to process. It can be easily implemented into the clinic and can potentially replace the use of external surrogates

Development of a realistic, dynamic digital brain phantom for CT perfusion validation

Science.gov (United States)

Divel, Sarah E.; Segars, W. Paul; Christensen, Soren; Wintermark, Max; Lansberg, Maarten G.; Pelc, Norbert J.

2016-03-01

Physicians rely on CT Perfusion (CTP) images and quantitative image data, including cerebral blood flow, cerebral blood volume, and bolus arrival delay, to diagnose and treat stroke patients. However, the quantification of these metrics may vary depending on the computational method used. Therefore, we have developed a dynamic and realistic digital brain phantom upon which CTP scans can be simulated based on a set of ground truth scenarios. Building upon the previously developed 4D extended cardiac-torso (XCAT) phantom containing a highly detailed brain model, this work consisted of expanding the intricate vasculature by semi-automatically segmenting existing MRA data and fitting nonuniform rational B-spline surfaces to the new vessels. Using time attenuation curves input by the user as reference, the contrast enhancement in the vessels changes dynamically. At each time point, the iodine concentration in the arteries and veins is calculated from the curves and the material composition of the blood changes to reflect the expected values. CatSim, a CT system simulator, generates simulated data sets of this dynamic digital phantom which can be further analyzed to validate CTP studies and post-processing methods. The development of this dynamic and realistic digital phantom provides a valuable resource with which current uncertainties and controversies surrounding the quantitative computations generated from CTP data can be examined and resolved.

A case of severe sepsis presenting marked decrease of neutrophils and interesting findings on dynamic CT.

Science.gov (United States)

Makino, Isamu; Tajima, Hidehiro; Kitagawa, Hirohisa; Nakagawara, Hisatoshi; Miyashita, Tomoharu; Nakanuma, Shinichi; Hayashi, Hironori; Takamura, Hiroyuki; Fushida, Sachio; Ohta, Tetsuo

2015-05-28

In a patient with severe sepsis, we sometimes observe immediate decrease of the counts of white blood cells (WBCs) and neutrophils, which is known as an indicator for poor prognosis. We observed marked decrease of white blood cells and neutrophils on blood examination and interesting findings on dynamic CT. Here, we present the case of a patient with severe postoperative sepsis occurring after major abdominal surgery and we discuss the mechanism of such clinical presentations. A 60-year-old man received pancreatoduodenectomy with colectomy for pancreatic cancer. He developed a high fever on postoperative day 3. We observed marked decrease of WBCs and neutrophils on blood examination. We also observed slight swelling of the liver, inhomogeneous enhancement of liver parenchyma in arterial phase, and periportal low density in the Glisson capsule in portal phase, without any findings indicating infectious complications on dynamic CT. WBCs and neutrophils increased above normal range in just 6 hours. Blood culture examination performed while the patient had a high fever was positive for Aeromonas hydrophila. After receiving intensive care, he promptly recovered from severe sepsis. The CT findings disappeared on second dynamic CT examination performed 3 days after the first examination. We treated a patient with severe sepsis after major abdominal surgery who presented very rapid change of the counts of WBCs and neutrophils and interesting CT findings in the liver. We rescued him from a critical situation by prompt and intensive treatment. Research is needed to accumulate and analyze data from more patients who present a similar clinical course to better understand their pathophysiological conditions.

2D and 3D CT Radiomics Features Prognostic Performance Comparison in Non-Small Cell Lung Cancer

Directory of Open Access Journals (Sweden)

Chen Shen

2017-12-01

Full Text Available OBJECTIVE: To compare 2D and 3D radiomics features prognostic performance differences in CT images of non-small cell lung cancer (NSCLC. METHOD: We enrolled 588 NSCLC patients from three independent cohorts. Two sets of 463 patients from two different institutes were used as the training cohort. The remaining cohort with 125 patients was set as the validation cohort. A total of 1014 radiomics features (507 2D features and 507 3D features correspondingly were assessed. Based on the dichotomized survival data, 2D and 3D radiomics indicators were calculated for each patient by trained classifiers. We used the area under the receiver operating characteristic curve (AUC to assess the prediction performance of trained classifiers (the support vector machine and logistic regression. Kaplan–Meier and Cox hazard survival analyses were also employed. Harrell's concordance index (C-Index and Akaike's information criteria (AIC were applied to assess the trained models. RESULTS: Radiomics indicators were built and compared by AUCs. In the training cohort, 2D_AUC = 0.653, 3D_AUC = 0.671. In the validation cohort, 2D_AUC = 0.755, 3D_AUC = 0.663. Both 2D and 3D trained indicators achieved significant results (P < .05 in the Kaplan-Meier analysis and Cox regression. In the validation cohort, 2D Cox model had a C-Index = 0.683 and AIC = 789.047; 3D Cox model obtained a C-Index = 0.632 and AIC = 799.409. CONCLUSION: Both 2D and 3D CT radiomics features have a certain prognostic ability in NSCLC, but 2D features showed better performance in our tests. Considering the cost of the radiomics features calculation, 2D features are more recommended for use in the current study.

320-Multidetector row whole-head dynamic subtracted CT angiography and whole-brain CT perfusion before and after carotid artery stenting: Technical note

International Nuclear Information System (INIS)

San Millan Ruiz, Diego; Murphy, Kieran; Gailloud, Philippe

2010-01-01

Introduction: Multidetector CT (MDCT) is increasingly used for the investigation of neurovascular disorders, but restricted z-axis coverage (3.2 cm for 64-MDCT) currently limits perfusion to a small portion of the brain close to the circle of Willis, and precludes dynamic angiographic appreciation of the entire brain circulation. We illustrate the clinical potential of recently developed 320-MDCT extending the z-axis coverage to 16 cm in a patient with symptomatic carotid artery stenosis. Methods: In a 74-year-old patient presenting with critical symptomatic stenosis of the left CCA, pre- and post-carotid artery stenting whole-head subtracted dynamic MDCT angiography and perfusion were obtained in addition to CT angiography of the supra-aortic trunks. Both whole-head subtracted MDCT angiography and perfusion demonstrated delayed left ICA circulation, which normalized after carotid stenting. Discussion: 320-MDCT offers unprecedented z-axis coverage allowing for whole-brain perfusion and subtracted dynamic angiography of the entire intracranial circulation. These innovations can consolidate the role of MDCT as a first intention imaging technique for cerebrovascular disorders, in particular for the acute management of stroke.

Multimodality functional imaging of spontaneous canine tumors using 64Cu-ATSM and 18FDG PET/CT and dynamic contrast enhanced perfusion CT

International Nuclear Information System (INIS)

Hansen, Anders E.; Kristensen, Annemarie T.; Law, Ian; McEvoy, Fintan J.; Kjær, Andreas; Engelholm, Svend A.

2012-01-01

Purpose: To compare the distribution and uptake of the hypoxia tracer 64 Cu-diacetyl-bis(N 4 -methylthiosemicarbazone) ( 64 Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition 64 Cu-ATSM distribution over time was evaluated. Methods and materials: Nine spontaneous cancer-bearing dogs were prospectively enrolled. FDG (1 h pi.) and 64 Cu-ATSM (3 and 24 h pi.) PET/CT were performed over three consecutive days. DCE-pCT was performed on day 2. Tumor uptake of FDG and 64 Cu-ATSM was assessed semi-quantitatively and the distribution of FDG, 64 Cu-ATSM and CT perfusion parameters correlated. Results: 64 Cu-ATSM distribution on scans performed 24 h apart displayed moderate to strong correlation; however, temporal changes were observed. The spatial distribution pattern of 64 Cu-ATSM between scans was moderately to strongly positively correlated to FDG, whereas the correlation of CT perfusion parameters to FDG and to 64 Cu-ATSM yielded more varying results. Conclusions: 64 Cu-ATSM uptake was positively correlated to FDG. 64 Cu-ATSM was found to be relatively stable between PET scans performed at different time points, important temporal changes were however observed in hypo-perfused regions. These findings potentially indicate that prolonged uptake periods for 64 Cu-ATSM imaging may be needed. Although a moderate to strong correlation between 64 Cu-ATSM and FDG PET/CT is observed, the two tracers provide different biological information with an overlapping spatial distribution.

SU-E-J-256: Predicting Metastasis-Free Survival of Rectal Cancer Patients Treated with Neoadjuvant Chemo-Radiotherapy by Data-Mining of CT Texture Features of Primary Lesions

International Nuclear Information System (INIS)

Zhong, H; Wang, J; Shen, L; Hu, W; Wan, J; Zhou, Z; Zhang, Z

2015-01-01

Purpose: The purpose of this study is to investigate the relationship between computed tomographic (CT) texture features of primary lesions and metastasis-free survival for rectal cancer patients; and to develop a datamining prediction model using texture features. Methods: A total of 220 rectal cancer patients treated with neoadjuvant chemo-radiotherapy (CRT) were enrolled in this study. All patients underwent CT scans before CRT. The primary lesions on the CT images were delineated by two experienced oncologists. The CT images were filtered by Laplacian of Gaussian (LoG) filters with different filter values (1.0–2.5: from fine to coarse). Both filtered and unfiltered images were analyzed using Gray-level Co-occurrence Matrix (GLCM) texture analysis with different directions (transversal, sagittal, and coronal). Totally, 270 texture features with different species, directions and filter values were extracted. Texture features were examined with Student’s t-test for selecting predictive features. Principal Component Analysis (PCA) was performed upon the selected features to reduce the feature collinearity. Artificial neural network (ANN) and logistic regression were applied to establish metastasis prediction models. Results: Forty-six of 220 patients developed metastasis with a follow-up time of more than 2 years. Sixtyseven texture features were significantly different in t-test (p<0.05) between patients with and without metastasis, and 12 of them were extremely significant (p<0.001). The Area-under-the-curve (AUC) of ANN was 0.72, and the concordance index (CI) of logistic regression was 0.71. The predictability of ANN was slightly better than logistic regression. Conclusion: CT texture features of primary lesions are related to metastasisfree survival of rectal cancer patients. Both ANN and logistic regression based models can be developed for prediction

Intramural hypoattenuated nodules in thickened wall of the gallbladder; CT features according to their primary causes

International Nuclear Information System (INIS)

Lee, Jun Hyung; Ha, Hyun Kwon; Lee, Jeong Hyun; Lee, Jean Hwa; Kim, Tae Kyoung; Kim, Pyo Nyun; Lee, Moon Gyu; Kim, Myung-Jin

2001-01-01

According to published reports, a common feature of xanthogranulomatous cholecystitis is the presence of intramural hypoattenuated nodules in thickened gallbladder wall. These nodules can, however, also be seen in pathological conditions such as acute cholecystitis, hyperplastic cholecystoses (cholesterolosis and adenomyomatosis), gallbladder cancer, and other inflammatory diseases such as tuberculosis. Retrospective review of the abdominal CT findings in 622 patients who for various reasons underwent cholecystectomy during a one-year period showed that intramural nodules were present in 60. In this pictorial essay we illustrate the imaging features of the many different pathological conditions which give rise to intramural hypoattenuated nodules in thickened wall of the gallbladder, correlating these features with the histopathological findings

Collateral Ventilation to Congenital Hyperlucent Lung Lesions Assessed on Xenon-Enhanced Dynamic Dual-Energy CT: an Initial Experience

OpenAIRE

Goo, Hyun Woo; Yang, Dong Hyun; Kim, Namkug; Park, Seung Il; Kim, Dong Kwan; Kim, Ellen Ai-Rhan

2011-01-01

Objective We wanted to evaluate the resistance to collateral ventilation in congenital hyperlucent lung lesions and to correlate that with the anatomic findings on xenon-enhanced dynamic dual-energy CT. Materials and Methods Xenon-enhanced dynamic dual-energy CT was successfully and safely performed in eight children (median age: 5.5 years, 4 boys and 4 girls) with congenital hyperlucent lung lesions. Functional assessment of the lung lesions on the xenon map was done, including performing a ...

Perivascular epithelioid cell tumour: Dynamic CT, MRI and clinicopathological characteristics—Analysis of 32 cases and review of the literature

International Nuclear Information System (INIS)

Tan, Y.; Zhang, H.; Xiao, E.-H.

2013-01-01

Aim: To evaluate the dynamic computed tomography (CT), magnetic resonance imaging (MRI), and clinicopathological characteristics of perivascular epithelioid cell tumours (PEComas), thus improving the diagnosis of the tumour. Materials and methods: A retrospective analysis was undertaken of the dynamic CT, MRI, and clinicopathological characteristics of 32 PEComas diagnosed at histopathology during the period 1 January 2005 to 1 March 2012 at two hospitals. Results: The age of the patients ranged from 14–80 years (mean 43.3 years). There were more women in this group (19/32). Solitary tumours were identified in kidney (n = 16), liver (n = 7), gynaecological organs (n = 2), retroperitoneal soft tissue (n = 2), lung (n = 2), palate (n = 1), left groin (n = 1). One patient had multiple tumours in the liver, kidney, and retroperitoneal soft tissue. Dynamic CT (32 cases) and MRI (15 cases) demonstrated tumours that were of low density or hypointense on T1-weighted imaging (WI) and hyperintense on T2WI; some were isodense with fat (CT: 10/32; MRI: 6/15). The tumours usually had well-defined borders and were of a regular shape (CT: 26/32; MRI: 12/15). Tumour diameters ranged from 1.5–18 cm (mean 5.1 cm). Most tumours (CT: 21/32, MRI: 10/15) enhanced heterogeneously and significantly on arterial and venous phases. Tumours appeared slightly hypodense on delayed CT imaging, although some (6/32) had delayed enhancement. The expression rate of HMB-45 (human melanoma black monoclonal antibody) was 100% (32/32). Histological classification in 22 cases (22/32) was epithelioid angiomyolipoma (AML), three (3/32) were clear cell “sugar” tumours (CCSTs), two (2/32) were lymphangioleiomyomatosis (LAM), and two (2/32) were clear cell myomelanocytic tumours of the falciform ligament/ligamentum teres (CCMMT). Three tumours did not have a specific classification. Conclusion: Knowledge of dynamic CT, MRI, and clinicopathological characteristics could help improve the diagnosis of

Development of a guideline on reading CT images of malignant pleural mesothelioma and selection of the reference CT films

International Nuclear Information System (INIS)

Zhou, Huashi; Tamura, Taro; Kusaka, Yukinori; Suganuma, Narufumi; Subhannachart, Ponglada; Vijitsanguan, Chomphunut; Noisiri, Weeraya; Hering, Kurt G.; Akira, Masanori; Itoh, Harumi

2012-01-01

Purpose: International experts developed a guideline on reading CT images of malignant pleural mesothelioma for radiologists and physicians. It is intended that it act as a supplement to the current International Classification of HRCT for Occupational and Environmental Respiratory Diseases. Methods: The research literatures on mesothelioma CT features were systematically reviewed. Ten mesothelioma CT features were adopted into the guideline prepared according to experts’ opinion. The terminology of mesothelioma CT features and mesothelioma probability were agreed by consensus of experts. The CT reference films for each mesothelioma feature were selected based on agreement by experts from 22 definite mesothelioma cases confirmed pathologically and immunohistochemically. To support the validity of the mesothelioma probability, 4 experts’ readings of CT films from 57 cases with or without mesothelioma were analyzed by kappa statistics between the experts; sensitivity and specificity for mesothelioma were also assessed. Results: The mesothelioma CT Guideline was developed, providing the terminology of CT features and the mesothelioma probability, the judgement of severity, the distribution of mesothelioma, and the revised CT reading sheet including mesothelioma items. The CT reference films with ten mesothelioma typical features were selected. The average linearly and quadratically weighted kappa of the agreement on the 4-point scale mesothelioma probability were 0.58 and 0.71, respectively. The average sensitivity and specificity for mesothelioma were 93.2% and 65.6%, respectively. Conclusion: The evidence-based mesothelioma CT Guideline developed may serve as a good educational tool to facilitate physicians in recognising mesothelioma and improve their proficiency in diagnosis of mesothelioma.

Development of a guideline on reading CT images of malignant pleural mesothelioma and selection of the reference CT films

Energy Technology Data Exchange (ETDEWEB)

Zhou, Huashi, E-mail: zhouhua@u-fukui.ac.jp [Department of Environmental Health, School of Medicine, University of Fukui, 23-3 Shimoaitsuki, Matsuoka, Eihezi-cho, Fukui Prefecture 910-1193 (Japan); Tamura, Taro, E-mail: tarou@u-fukui.ac.jp [Department of Environmental Health, School of Medicine, University of Fukui, 23-3 Shimoaitsuki, Matsuoka, Eihezi-cho, Fukui Prefecture 910-1193 (Japan); Kusaka, Yukinori, E-mail: kusakayk@gmail.com [Department of Environmental Health, School of Medicine, University of Fukui, 23-3 Shimoaitsuki, Matsuoka, Eihezi-cho, Fukui Prefecture 910-1193 (Japan); Suganuma, Narufumi, E-mail: nsuganuma@kochi-u.ac.jp [Department of Environmental Medicine, Kochi University School of Medicine (Japan); Subhannachart, Ponglada, E-mail: pongladas@gmail.com [Central Chest Disease Institute of Thailand, 39 Moo 9, Tiwanon Road, Muang Nonthaburi 11000 (Thailand); Vijitsanguan, Chomphunut, E-mail: Chompoo_vj@yahoo.com [Central Chest Disease Institute of Thailand, 39 Moo 9, Tiwanon Road, Muang Nonthaburi 11000 (Thailand); Noisiri, Weeraya, E-mail: weeraya_tat@yahoo.com [Central Chest Disease Institute of Thailand, 39 Moo 9, Tiwanon Road, Muang Nonthaburi 11000 (Thailand); Hering, Kurt G., E-mail: k.g.hering@t-online.de [Department of Diagnostic Radiology, Radiooncology and Nuclear Medicine, Radiological Clinic, Miner' s Hospital, Radiologische Klinik, Lansppaschaftskranhaus Dortmund, Wieckesweg 27 44309, Dortmund (Germany); Akira, Masanori, E-mail: akira@kch.hosp.go.jp [Department of Radiology, National Hospital Organization Kinki-Chuo Chest Medical Center, 1180 Nagasone-cho, Kita-ku, Sakai, Osaka 591-8555 (Japan); Itoh, Harumi, E-mail: hitoh@fmsrsa.fukui-med.ac.jp [Department of Environmental Health, School of Medicine, University of Fukui, 23-3 Shimoaitsuki, Matsuoka, Eihezi-cho, Fukui Prefecture 910-1193 (Japan); Department of Radiology, School of Medicine, University of Fukui, 23-3 Shimoaitsuki Matsuoka, Eiheizi-cho, Fukui Prefecture 910-1193 (Japan); and others

2012-12-15

Purpose: International experts developed a guideline on reading CT images of malignant pleural mesothelioma for radiologists and physicians. It is intended that it act as a supplement to the current International Classification of HRCT for Occupational and Environmental Respiratory Diseases. Methods: The research literatures on mesothelioma CT features were systematically reviewed. Ten mesothelioma CT features were adopted into the guideline prepared according to experts’ opinion. The terminology of mesothelioma CT features and mesothelioma probability were agreed by consensus of experts. The CT reference films for each mesothelioma feature were selected based on agreement by experts from 22 definite mesothelioma cases confirmed pathologically and immunohistochemically. To support the validity of the mesothelioma probability, 4 experts’ readings of CT films from 57 cases with or without mesothelioma were analyzed by kappa statistics between the experts; sensitivity and specificity for mesothelioma were also assessed. Results: The mesothelioma CT Guideline was developed, providing the terminology of CT features and the mesothelioma probability, the judgement of severity, the distribution of mesothelioma, and the revised CT reading sheet including mesothelioma items. The CT reference films with ten mesothelioma typical features were selected. The average linearly and quadratically weighted kappa of the agreement on the 4-point scale mesothelioma probability were 0.58 and 0.71, respectively. The average sensitivity and specificity for mesothelioma were 93.2% and 65.6%, respectively. Conclusion: The evidence-based mesothelioma CT Guideline developed may serve as a good educational tool to facilitate physicians in recognising mesothelioma and improve their proficiency in diagnosis of mesothelioma.

A clinical study of major stroke cases of a low-perfusion pattern on a dynamic CT scan

International Nuclear Information System (INIS)

Shimada, Tsutomu; Kaneko, Mitsuo; Tanaka, Keisei; Sugiura, Masashi

1986-01-01

Preoperative dynamic CT scans have been done for the past 4 years in order to estimate the degree of ischemia in the region responsible. The hemodynamic patterns on the dynamic CT scans were consequently classified into three particular types: Type 1: The collateral flow was preserved considerably, and the peak value of the time-density curve exceeded 50 % of the opposite healthy side. Type 2: The residual flow was moderate, and the peak value was approximately from one-third to one-half of the normal side. Type 3: The residual flow was minimal, and the time-density curve was almost flat or the peak value did not reach even approximately one-third of the opposite side. In general, major stroke cases with a Type 1 pattern on the dynamic CT scan showed a considerably good recovery if the revascularization was completed within 6 hours after the attack. However, cases of the Type 3 pattern often developed into a massive cerebral infarction associated with a marked mid-line shift, and sometimes they were fulminent even after acute revascularization. In this paper, clinical results of 11 major stroke cases with the Type 2 pattern on dynamic CT scans were evaluated. All of them showed hemiplegia, with or without aphasia, just after the onset of the stroke, and dynamic CT scans were performed within 24 hours. The site of the occluded vessel was in the internal carotid artery (ICA) in 4 cases and in the middle cerebral artery (MCA) in 6; severe stenosis in ICA and MCA was found in only one case. The functional recovery was rather poor. Only one was capable of self-care at home; four others required partial care at home, and the other six were bed-ridden. In the 4 surgical cases of acute revascularization, the clinical symptoms did not improve, and the functional recovery was almost equivalent to the natural course. (J.P.N.)

Auditing SNOMED CT hierarchical relations based on lexical features of concepts in non-lattice subgraphs.

Science.gov (United States)

Cui, Licong; Bodenreider, Olivier; Shi, Jay; Zhang, Guo-Qiang

2018-02-01

We introduce a structural-lexical approach for auditing SNOMED CT using a combination of non-lattice subgraphs of the underlying hierarchical relations and enriched lexical attributes of fully specified concept names. Our goal is to develop a scalable and effective approach that automatically identifies missing hierarchical IS-A relations. Our approach involves 3 stages. In stage 1, all non-lattice subgraphs of SNOMED CT's IS-A hierarchical relations are extracted. In stage 2, lexical attributes of fully-specified concept names in such non-lattice subgraphs are extracted. For each concept in a non-lattice subgraph, we enrich its set of attributes with attributes from its ancestor concepts within the non-lattice subgraph. In stage 3, subset inclusion relations between the lexical attribute sets of each pair of concepts in each non-lattice subgraph are compared to existing IS-A relations in SNOMED CT. For concept pairs within each non-lattice subgraph, if a subset relation is identified but an IS-A relation is not present in SNOMED CT IS-A transitive closure, then a missing IS-A relation is reported. The September 2017 release of SNOMED CT (US edition) was used in this investigation. A total of 14,380 non-lattice subgraphs were extracted, from which we suggested a total of 41,357 missing IS-A relations. For evaluation purposes, 200 non-lattice subgraphs were randomly selected from 996 smaller subgraphs (of size 4, 5, or 6) within the "Clinical Finding" and "Procedure" sub-hierarchies. Two domain experts confirmed 185 (among 223) suggested missing IS-A relations, a precision of 82.96%. Our results demonstrate that analyzing the lexical features of concepts in non-lattice subgraphs is an effective approach for auditing SNOMED CT. Copyright © 2017 Elsevier Inc. All rights reserved.

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

Science.gov (United States)

Xu, Jian-Wu; Suzuki, Kenji

2014-03-01

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

SU-F-R-30: Interscanner Variability of Radiomics Features in Computed Tomography (CT) Using a Standard ACR Phantom

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Shafiq ul Hassan, M; Zhang, G; Moros, E [H Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Department of Physics, University of South Florida, Tampa, FL (United States); Budzevich, M; Latifi, K; Hunt, D; Gillies, R [H Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States)

2016-06-15

Purpose: A simple approach to investigate Interscanner variability of Radiomics features in computed tomography (CT) using a standard ACR phantom. Methods: The standard ACR phantom was scanned on CT scanners from three different manufacturers. Scanning parameters of 120 KVp, 200 mA were used while slice thickness of 3.0 mm on two scanners and 3.27 mm on third scanner was used. Three spherical regions of interest (ROI) from water, medium density and high density inserts were contoured. Ninety four Radiomics features were extracted using an in-house program. These features include shape (11), intensity (22), GLCM (26), GLZSM (11), RLM (11), and NGTDM (5) and 8 fractal dimensions features. To evaluate the Interscanner variability across three scanners, a coefficient of variation (COV) is calculated for each feature group. Each group is further classified according to the COV- by calculating the percentage of features in each of the following categories: COV less than 2%, between 2 and 10% and greater than 10%. Results: For all feature groups, similar trend was observed for three different inserts. Shape features were the most robust for all scanners as expected. 70% of the shape features had COV <2%. For intensity feature group, 2% COV varied from 9 to 32% for three scanners. All features in four groups GLCM, GLZSM, RLM and NGTDM were found to have Interscanner variability ≥2%. The fractal dimensions dependence for medium and high density inserts were similar while it was different for water inserts. Conclusion: We concluded that even for similar scanning conditions, Interscanner variability across different scanners was significant. The texture features based on GLCM, GLZSM, RLM and NGTDM are highly scanner dependent. Since the inserts of the ACR Phantom are not heterogeneous in HU values suggests that matrix based 2nd order features are highly affected by variation in noise. Research partly funded by NIH/NCI R01CA190105-01.

SU-E-J-251: Incorporation of Pre-Therapy 18F-FDG Uptake with CT Texture Features in a Predictive Model for Radiation Pneumonitis Development

International Nuclear Information System (INIS)

Anthony, G; Cunliffe, A; Armato, S; Al-Hallaq, H; Castillo, R; Pham, N; Guerrero, T

2015-01-01

Purpose: To determine whether the addition of standardized uptake value (SUV) statistical variables to CT lung texture features can improve a predictive model of radiation pneumonitis (RP) development in patients undergoing radiation therapy. Methods: Anonymized data from 96 esophageal cancer patients (18 RP-positive cases of Grade ≥ 2) were retrospectively collected including pre-therapy PET/CT scans, pre-/posttherapy diagnostic CT scans and RP status. Twenty texture features (firstorder, fractal, Laws’ filter and gray-level co-occurrence matrix) were calculated from diagnostic CT scans and compared in anatomically matched regions of the lung. The mean, maximum, standard deviation, and 50th–95th percentiles of the SUV values for all lung voxels in the corresponding PET scans were acquired. For each texture feature, a logistic regression-based classifier consisting of (1) the average change in that texture feature value between the pre- and post-therapy CT scans and (2) the pre-therapy SUV standard deviation (SUV SD ) was created. The RP-classification performance of each logistic regression model was compared to the performance of its texture feature alone by computing areas under the receiver operating characteristic curves (AUCs). T-tests were performed to determine whether the mean AUC across texture features changed significantly when SUV SD was added to the classifier. Results: The AUC for single-texturefeature classifiers ranged from 0.58–0.81 in high-dose (≥ 30 Gy) regions of the lungs and from 0.53–0.71 in low-dose (< 10 Gy) regions. Adding SUVSD in a logistic regression model using a 50/50 data partition for training and testing significantly increased the mean AUC by 0.08, 0.06 and 0.04 in the low-, medium- and high-dose regions, respectively. Conclusion: Addition of SUVSD from a pre-therapy PET scan to a single CT-based texture feature improves RP-classification performance on average. These findings demonstrate the potential for more

SU-E-J-251: Incorporation of Pre-Therapy 18F-FDG Uptake with CT Texture Features in a Predictive Model for Radiation Pneumonitis Development

Energy Technology Data Exchange (ETDEWEB)

Anthony, G; Cunliffe, A; Armato, S; Al-Hallaq, H [The University of Chicago, Chicago, IL (United States); Castillo, R [Univ Texas Medical Branch of Galveston, Pearland, TX (United States); Pham, N [Baylor College of Medicine, Houston, TX (United States); Guerrero, T [Beaumont Health System, Royal Oak, MI (United States)

2015-06-15

Purpose: To determine whether the addition of standardized uptake value (SUV) statistical variables to CT lung texture features can improve a predictive model of radiation pneumonitis (RP) development in patients undergoing radiation therapy. Methods: Anonymized data from 96 esophageal cancer patients (18 RP-positive cases of Grade ≥ 2) were retrospectively collected including pre-therapy PET/CT scans, pre-/posttherapy diagnostic CT scans and RP status. Twenty texture features (firstorder, fractal, Laws’ filter and gray-level co-occurrence matrix) were calculated from diagnostic CT scans and compared in anatomically matched regions of the lung. The mean, maximum, standard deviation, and 50th–95th percentiles of the SUV values for all lung voxels in the corresponding PET scans were acquired. For each texture feature, a logistic regression-based classifier consisting of (1) the average change in that texture feature value between the pre- and post-therapy CT scans and (2) the pre-therapy SUV standard deviation (SUV{sub SD}) was created. The RP-classification performance of each logistic regression model was compared to the performance of its texture feature alone by computing areas under the receiver operating characteristic curves (AUCs). T-tests were performed to determine whether the mean AUC across texture features changed significantly when SUV{sub SD} was added to the classifier. Results: The AUC for single-texturefeature classifiers ranged from 0.58–0.81 in high-dose (≥ 30 Gy) regions of the lungs and from 0.53–0.71 in low-dose (< 10 Gy) regions. Adding SUVSD in a logistic regression model using a 50/50 data partition for training and testing significantly increased the mean AUC by 0.08, 0.06 and 0.04 in the low-, medium- and high-dose regions, respectively. Conclusion: Addition of SUVSD from a pre-therapy PET scan to a single CT-based texture feature improves RP-classification performance on average. These findings demonstrate the potential for

MO-DE-207B-11: Reliability of PET/CT Radiomics Features in Functional and Morphological Components of NSCLC Lesions: A Repeatability Analysis in a Prospective Multicenter Cohort

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Desseroit, M [INSERM, LaTIM UMR 1101, Brest (France); EE DACTIM, CHU de Poitiers, Poitiers (France); Tixier, F; Cheze Le Rest, C [EE DACTIM, CHU de Poitiers, Poitiers (France); Majdoub, M; Visvikis, D; Hatt, M [INSERM, LaTIM UMR 1101, Brest (France); Weber, W [Memorial Sloan Kettering Cancer Center, New-york, NY (United States); Siegel, B [Washington University School of Medicine, St Louis, MO (United States)

2016-06-15

Purpose: The goal of this study was to evaluate the repeatability of radiomics features (intensity, shape and heterogeneity) in both PET and low-dose CT components of test-retest FDG-PET/CT images in a prospective multicenter cohort of 74 NSCLC patients from ACRIN 6678 and a similar Merck trial. Methods: Seventy-four patients with stage III-IV NCSLC were prospectively included. The primary tumor and up to 3 additional lesions per patient were analyzed. The Fuzzy Locally Adaptive Bayesian algorithm was used to automatically delineate metabolically active volume (MAV) in PET. The 3D SlicerTM software was exploited to delineate anatomical volumes (AV) in CT. Ten intensity first-order features, as well as 26 textural features and four 3D shape descriptors were calculated from tumour volumes in both modalities. The repeatability of each metric was assessed by Bland-Altman analysis. Results: One hundred and five lesions (primary tumors and nodal or distant metastases) were delineated and characterized. The MAV and AV determination had a repeatability of −1.4±11.0% and −1.2±18.7% respectively. Several shape and heterogeneity features were found to be highly or moderately repeatable (e.g., sphericity, co-occurrence entropy or intensity size-zone matrix zone percentage), whereas others were confirmed as unreliable with much higher variability (more than twice that of the corresponding volume determination). Conclusion: Our results in this large multicenter cohort with more than 100 measurements confirm the PET findings in previous studies (with <30 lesions). In addition, our study is the first to explore the repeatability of radiomics features in the low-dose CT component of PET/CT acquisitions (previous studies considered dosimetry CT, CE-CT or CBCT). Several features were identified as reliable in both PET and CT components and could be used to build prognostic models. This work has received a French government support granted to the CominLabs excellence laboratory

Predicting Response to Neoadjuvant Chemoradiotherapy in Esophageal Cancer with Textural Features Derived from Pretreatment 18F-FDG PET/CT Imaging.

Science.gov (United States)

Beukinga, Roelof J; Hulshoff, Jan B; van Dijk, Lisanne V; Muijs, Christina T; Burgerhof, Johannes G M; Kats-Ugurlu, Gursah; Slart, Riemer H J A; Slump, Cornelis H; Mul, Véronique E M; Plukker, John Th M

2017-05-01

Adequate prediction of tumor response to neoadjuvant chemoradiotherapy (nCRT) in esophageal cancer (EC) patients is important in a more personalized treatment. The current best clinical method to predict pathologic complete response is SUV max in 18 F-FDG PET/CT imaging. To improve the prediction of response, we constructed a model to predict complete response to nCRT in EC based on pretreatment clinical parameters and 18 F-FDG PET/CT-derived textural features. Methods: From a prospectively maintained single-institution database, we reviewed 97 consecutive patients with locally advanced EC and a pretreatment 18 F-FDG PET/CT scan between 2009 and 2015. All patients were treated with nCRT (carboplatin/paclitaxel/41.4 Gy) followed by esophagectomy. We analyzed clinical, geometric, and pretreatment textural features extracted from both 18 F-FDG PET and CT. The current most accurate prediction model with SUV max as a predictor variable was compared with 6 different response prediction models constructed using least absolute shrinkage and selection operator regularized logistic regression. Internal validation was performed to estimate the model's performances. Pathologic response was defined as complete versus incomplete response (Mandard tumor regression grade system 1 vs. 2-5). Results: Pathologic examination revealed 19 (19.6%) complete and 78 (80.4%) incomplete responders. Least absolute shrinkage and selection operator regularization selected the clinical parameters: histologic type and clinical T stage, the 18 F-FDG PET-derived textural feature long run low gray level emphasis, and the CT-derived textural feature run percentage. Introducing these variables to a logistic regression analysis showed areas under the receiver-operating-characteristic curve (AUCs) of 0.78 compared with 0.58 in the SUV max model. The discrimination slopes were 0.17 compared with 0.01, respectively. After internal validation, the AUCs decreased to 0.74 and 0.54, respectively. Conclusion

CT diagnosis of cystic ovarian lesions

International Nuclear Information System (INIS)

Iio, Kazuto; Shinmura, Ryoji; Arima, Naomi; Yamada, Eiichiro; Ohkubo, Koichi; Nagata, Yukihiro

1985-01-01

CT was undertaken and CT numbers were measured in 47 patients with cystic ovarian lesions. CT features particularly for chocolate cyst revealed the uniform thickness of the whole cystic wall, findings suggesting adhesion to the surrounding organs, circular or oval shape, and higher CT numbers within the cyst than those in the other cystic ovarian lesions. However, because these features are not always observed in cases of chocolate cyst, one should not rely solely on CT findings in the diagnosis of chocolate cyst. (Namekawa, K.)

Collateral ventilation to congenital hyperlucent lung lesions assessed on xenon-enhanced dynamic dual-energy CT: an initial experience.

Science.gov (United States)

Goo, Hyun Woo; Yang, Dong Hyun; Kim, Namkug; Park, Seung Il; Kim, Dong Kwan; Kim, Ellen Ai-Rhan

2011-01-01

We wanted to evaluate the resistance to collateral ventilation in congenital hyperlucent lung lesions and to correlate that with the anatomic findings on xenon-enhanced dynamic dual-energy CT. Xenon-enhanced dynamic dual-energy CT was successfully and safely performed in eight children (median age: 5.5 years, 4 boys and 4 girls) with congenital hyperlucent lung lesions. Functional assessment of the lung lesions on the xenon map was done, including performing a time-xenon value curve analysis and assessing the amplitude of xenon enhancement (A) value, the rate of xenon enhancement (K) value and the time of arrival value. Based on the A value, the lung lesions were categorized into high or low (A value > 10 Hounsfield unit [HU]) resistance to collateral ventilation. In addition, the morphologic CT findings of the lung lesions, including cyst, mucocele and an accessory or incomplete fissure, were assessed on the weighted-average CT images. The xenon-enhanced CT radiation dose was estimated. Five of the eight lung lesions were categorized into the high resistance group and three lesions were categorized into the low resistance group. The A and K values in the normal lung were higher than those in the low resistance group. The time of arrival values were delayed in the low resistance group. Cysts were identified in five lesions, mucocele in four, accessory fissure in three and incomplete fissure in two. Either cyst or an accessory fissure was seen in four of the five lesions showing high resistance to collateral ventilation. The xenon-enhanced CT radiation dose was 2.3 ± 0.6 mSv. Xenon-enhanced dynamic dual-energy CT can help visualize and quantitate various degrees of collateral ventilation to congenital hyperlucent lung lesions in addition to assessing the anatomic details of the lung.

Stability of deep features across CT scanners and field of view using a physical phantom

Science.gov (United States)

Paul, Rahul; Shafiq-ul-Hassan, Muhammad; Moros, Eduardo G.; Gillies, Robert J.; Hall, Lawrence O.; Goldgof, Dmitry B.

2018-02-01

Radiomics is the process of analyzing radiological images by extracting quantitative features for monitoring and diagnosis of various cancers. Analyzing images acquired from different medical centers is confounded by many choices in acquisition, reconstruction parameters and differences among device manufacturers. Consequently, scanning the same patient or phantom using various acquisition/reconstruction parameters as well as different scanners may result in different feature values. To further evaluate this issue, in this study, CT images from a physical radiomic phantom were used. Recent studies showed that some quantitative features were dependent on voxel size and that this dependency could be reduced or removed by the appropriate normalization factor. Deep features extracted from a convolutional neural network, may also provide additional features for image analysis. Using a transfer learning approach, we obtained deep features from three convolutional neural networks pre-trained on color camera images. An we examination of the dependency of deep features on image pixel size was done. We found that some deep features were pixel size dependent, and to remove this dependency we proposed two effective normalization approaches. For analyzing the effects of normalization, a threshold has been used based on the calculated standard deviation and average distance from a best fit horizontal line among the features' underlying pixel size before and after normalization. The inter and intra scanner dependency of deep features has also been evaluated.

Contrast between hypervascularized liver lesions and hepatic parenchyma. Early dynamic PET versus contrast-enhanced CT

International Nuclear Information System (INIS)

Freesmeyer, M.; Winkens, T.; Schierz, J.-H.

2014-01-01

To detect hypervascularized liver lesions, early dynamic (ED) 18 F-FDG PET may be an alternative when contrast-enhanced (CE) imaging is infeasible. This retrospective pilot analysis compared contrast between such lesions and liver parenchyma, an important objective image quality variable, in ED PET versus CE CT. Twenty-eight hypervascularized liver lesions detected by CE CT [21 (75%) hepatocellular carcinomas; mean (range) diameter 4.9 ± 3.5 (1-14) cm] in 20 patients were scanned with ED PET. Using regions of interest, maximum and mean lesional and parenchymal signals at baseline, arterial and venous phases were calculated for ED PET and CE CT. Lesional/parenchymal signal ratio was significantly higher (P < 0.005) with ED PET versus CE CT at the arterial phase and similar between the methods at the venous phase. In liver imaging, ED PET generates greater lesional-parenchymal contrast during the arterial phase than does CE CT; these observations should be formally, prospectively evaluated. (author)

A study for the correlation of hemorrhagic cerebral infarction with the hemodynamics measured by dynamic CT

International Nuclear Information System (INIS)

Shibagaki, Yasuro

1989-01-01

In 15 cases of cerebral infarction (9 embolisms, 6 thromboses), dynamic CT scans were repeatedly undertaken during 4 week period of stroke. The ratio of peak height to mean transit time (PH/MTT), which was calculated from density time curve, was used as an index of cerebral blood flow. Hemorrhagic infarction was defined as a high density area with CT value over 50 within low density area. The PH/MTT was significantly increased after the appearance of hemorrhagic infarction. Nine of 10 areas, in which hemorrhagic infarctions were not recognized after recoverry of PH/MTT to over 0.5, did not show hemorrhagic infarctions during 4 week period of stroke. The areas in which hemorrhagic infarctions appeared during 4 week period of stroke had mdore prolonged period of low PH/MTT values than the areas in which hemorrhagic infarctions were not recognized. In conclusion dynamic CT is useful for predicting hemorrhagic infarction. (author)

Perigastric appendagitis: CT and clinical features in eight patients

International Nuclear Information System (INIS)

Justaniah, A.I.; Scholz, F.J.; Katz, D.S.; Scheirey, C.D.

2014-01-01

Aim: To describe perigastric appendagitis (PA) on CT as a new and distinct clinical entity to enable recognition and prevent additional unnecessary investigation or intervention. Materials and methods: Institutional review board approval was obtained and informed consent was waived. Retrospective review of the clinical data and CT findings in eight patients with PA encountered over 10 years at one institution was performed. The English literature was reviewed and summarized. Two experienced abdominal radiologists reviewed the CT images by consensus. Results: Seven of eight patients had moderate to severe epigastric pain for 1–7 days. All eight patients (four men, four women; mean age 44 years, range 33–81 years) had no fever or leukocytosis. All underwent abdominal CT which showed ovoid fat inflammation along the course of the perigastric ligaments (gastrohepatic, gastrosplenic, and falciform). Two had gastric wall thickening. Although the inflammation was correctly described, the specific diagnosis was not made on initial interpretation in five patients. Subsequently, they underwent further diagnostic testing [an upper gastrointestinal examination and hepatobiliary iminodiacetic acid (HIDA) cholescintigraphy, an upper endoscopy and MRI examination, HIDA cholescintigraphy, another CT, and an MRI examination, respectively]. The HIDA cholescintigraphy, upper GI examination, and upper endoscopy examinations were normal. No repeated examination was performed on the other three patients. Pain resolved spontaneously in all within two days. Conclusion: Perigastric appendagitis can present with an acute abdomen, which is safely managed conservatively if diagnosed correctly. Radiologists should be aware of the entity to avoid unnecessary intervention, and recognize the CT findings of ovoid fat inflammation in the distribution of the perigastric ligaments. - Highlights: • Normal perigastric ligaments can have fatty appendages. • Torsion of these appendages causes

Evaluation of pituitary adenomas by multidirectional multislice dynamic CT

International Nuclear Information System (INIS)

Abe, T.; Izumiyama, H.; Fujisawa, I.

2002-01-01

Purpose: Multidetector-row CT is a new technology with a short scanning time. Multislice dynamic CT (MSDCT) in various directions can be obtained using the multidetector-row CT with multiplanar reformatting (MPR) technique. Material and Methods: We evaluated the initial results of sagittal and coronal MSDCT images reconstructed by MPR (MSDCT-MPR) in 3 pituitary adenoma patients with a pacemaker. Results: In a patient with microadenoma, the maximum contrast between the normal anterior pituitary gland and the adenoma occurred approximately 50 s after the start of the contrast medium injection. A microadenoma was depicted as a less enhanced area relative to normal pituitary tissue. The macroadenomas were depicted as a less enhanced mass with cavernous sinus invasion in 1 patient and as a non-uniformly enhanced mass in another patient. Bone destruction and incomplete opening of the sellar floor during previous surgery were clearly detected in 2 patients with macroadenomas. These pituitary adenomas were removed via the transnasal route based on information from the MSDCT-MPR images only. The findings were verified surgically. Conclusion: The MSDCT-MPR provided the information needed for surgery with good image quality in the 3 patients with pacemakers. MSDCT-MPR appears to be a useful technique for patients with a pituitary adenoma in whom MR imaging is not available. This is the first report, to our knowledge, of the MSDCT-MPR technique being used to demonstrate pituitary disorders

Evaluation of pituitary adenomas by multidirectional multislice dynamic CT

Energy Technology Data Exchange (ETDEWEB)

Abe, T.; Izumiyama, H. [Showa Univ. School of Medicine, Tokyo (Japan). Dept. of Neurosurgery; Fujisawa, I. [Kishiwada City Hospital, Kishiwada (Japan). Dept. of Radiology

2002-11-01

Purpose: Multidetector-row CT is a new technology with a short scanning time. Multislice dynamic CT (MSDCT) in various directions can be obtained using the multidetector-row CT with multiplanar reformatting (MPR) technique. Material and Methods: We evaluated the initial results of sagittal and coronal MSDCT images reconstructed by MPR (MSDCT-MPR) in 3 pituitary adenoma patients with a pacemaker. Results: In a patient with microadenoma, the maximum contrast between the normal anterior pituitary gland and the adenoma occurred approximately 50 s after the start of the contrast medium injection. A microadenoma was depicted as a less enhanced area relative to normal pituitary tissue. The macroadenomas were depicted as a less enhanced mass with cavernous sinus invasion in 1 patient and as a non-uniformly enhanced mass in another patient. Bone destruction and incomplete opening of the sellar floor during previous surgery were clearly detected in 2 patients with macroadenomas. These pituitary adenomas were removed via the transnasal route based on information from the MSDCT-MPR images only. The findings were verified surgically. Conclusion: The MSDCT-MPR provided the information needed for surgery with good image quality in the 3 patients with pacemakers. MSDCT-MPR appears to be a useful technique for patients with a pituitary adenoma in whom MR imaging is not available. This is the first report, to our knowledge, of the MSDCT-MPR technique being used to demonstrate pituitary disorders.

Patients with liver FNH and HCC patients with negative AFP: plain and dynamic enhanced MRI and CT findings

Directory of Open Access Journals (Sweden)

LI Mingtong

2015-05-01

Full Text Available ObjectiveTo investigate plain and dynamic enhanced magnetic resonance imaging (MRI and computed tomography (CT findings in patients with focal nodular hyperplasia (FNH of the liver and hepatocellular carcinoma (HCC patients with negative alpha-fetoprotein (AFP. MethodsA statistical analysis was performed on the clinical data of 124 cases of liver tumor admitted to Beijing Miyun County Hospital from April 2012 to April 2014. ResultsFifty-five of the 74 patients with FNH underwent CT examination, among whom 38 patients received three-phase dynamic enhanced scan and 16 received only plain scan; 62 cases had plain and enhanced MRI with the application of contrast agent Gd-BOPTA in 42 patients. Among the 50 HCC patients with negative AFP, CT examination was performed in 40 and 10 only had plain scan; 46 patients received plain and enhanced MRI with the use of contrast agent Gd-BOPTA in 30. Delayed scan after 1-2 h demonstrated low signal in 30 lesions of the 30 cases. ConclusionFor patients with liver FNH and AFP-negative HCC patients, their plain and dynamic enhanced MRI and CT scan have respective characteristics. A combination of multiple examination methods can significantly improve diagnostic yield of the two diseases.

Feature extraction for dynamic integration of classifiers

NARCIS (Netherlands)

Pechenizkiy, M.; Tsymbal, A.; Puuronen, S.; Patterson, D.W.

2007-01-01

Recent research has shown the integration of multiple classifiers to be one of the most important directions in machine learning and data mining. In this paper, we present an algorithm for the dynamic integration of classifiers in the space of extracted features (FEDIC). It is based on the technique

Pancreatic adenocarcinoma: dual-phase helical CT with surgical and histopathologic correlation

International Nuclear Information System (INIS)

Kim, Eun A; Yoon, Kwon Ha; Park, Seong Hoon; Yun, Ki Jung; Won, Jong Jin

2003-01-01

To determine the accuracy of dual-phase helical CT in assessing the resectability of pancreatic ductal adenocarcinoma, and to correlate the CT findings with the surgical and histopathologic findings. Thirty patients with pathologically proven cancer of the pancreas underwent arterial-and portal-phase helical CT scanning, and in the two of these, single-level dynamic CT was performed during celiac and superior mesenteric arteriography. In 17 patients who underwent surgery for potentially resectable cancer of the pancreatic head, tumor resectability was assessed. The CT findings were analyzed and correlated with these of surgery and histopathology. In 13 (76%) of the 17 patients who underwent surgery, tumors were resectable. Their average size was 2.76 cm (arterial phase), 2.30 cm (portal phase), and 2.48 cm (pathologically determined) and the overall accuracy of helical CT for assessing resectability was 87%. In all patients, the central portion of the tumors exhibited hypoattenuation at both phases; the peripheral portion showed hypoattenuation at the arterial phase and iso- (n=10) or hyperattenuation (n=3) at the portal phase. Single-level dynamic CT depicted a persistently hypoattenuating central portion and progressive and prolonged enhancement of the periphery. CT-histopathologic correlation showed that central hypoattenuation indicated the presence of tumor cells, necrosis (n=3) and mucin (n=4), while the peripheral iso- or hyperattenuated areas seen at the portal phase represented fibrosis and inflammatory infiltration. Histopathologic examination revealed tumoral infiltration of peripancreatic fat tissue (n=11) and microvascular invasion of major peripancreatic vessels (n=7). The dual-phase helical CT is useful in the determination of resectability in pancreas cancer and CT findings represent well the histopathologic features of pancreas cancer

Pancreatic adenocarcinoma: dual-phase helical CT with surgical and histopathologic correlation

Energy Technology Data Exchange (ETDEWEB)

Kim, Eun A; Yoon, Kwon Ha; Park, Seong Hoon; Yun, Ki Jung; Won, Jong Jin [Wonkwang University School of Medicine, Iksan (Korea, Republic of)

2003-03-01

To determine the accuracy of dual-phase helical CT in assessing the resectability of pancreatic ductal adenocarcinoma, and to correlate the CT findings with the surgical and histopathologic findings. Thirty patients with pathologically proven cancer of the pancreas underwent arterial-and portal-phase helical CT scanning, and in the two of these, single-level dynamic CT was performed during celiac and superior mesenteric arteriography. In 17 patients who underwent surgery for potentially resectable cancer of the pancreatic head, tumor resectability was assessed. The CT findings were analyzed and correlated with these of surgery and histopathology. In 13 (76%) of the 17 patients who underwent surgery, tumors were resectable. Their average size was 2.76 cm (arterial phase), 2.30 cm (portal phase), and 2.48 cm (pathologically determined) and the overall accuracy of helical CT for assessing resectability was 87%. In all patients, the central portion of the tumors exhibited hypoattenuation at both phases; the peripheral portion showed hypoattenuation at the arterial phase and iso- (n=10) or hyperattenuation (n=3) at the portal phase. Single-level dynamic CT depicted a persistently hypoattenuating central portion and progressive and prolonged enhancement of the periphery. CT-histopathologic correlation showed that central hypoattenuation indicated the presence of tumor cells, necrosis (n=3) and mucin (n=4), while the peripheral iso- or hyperattenuated areas seen at the portal phase represented fibrosis and inflammatory infiltration. Histopathologic examination revealed tumoral infiltration of peripancreatic fat tissue (n=11) and microvascular invasion of major peripancreatic vessels (n=7). The dual-phase helical CT is useful in the determination of resectability in pancreas cancer and CT findings represent well the histopathologic features of pancreas cancer.

The Primary Care Electronic Library: RSS feeds using SNOMED-CT indexing for dynamic content delivery.

Science.gov (United States)

Robinson, Judas; de Lusignan, Simon; Kostkova, Patty; Madge, Bruce; Marsh, A; Biniaris, C

2006-01-01

Rich Site Summary (RSS) feeds are a method for disseminating and syndicating the contents of a website using extensible mark-up language (XML). The Primary Care Electronic Library (PCEL) distributes recent additions to the site in the form of an RSS feed. When new resources are added to PCEL, they are manually assigned medical subject headings (MeSH terms), which are then automatically mapped to SNOMED-CT terms using the Unified Medical Language System (UMLS) Metathesaurus. The library is thus searchable using MeSH or SNOMED-CT. Our syndicate partner wished to have remote access to PCEL coronary heart disease (CHD) information resources based on SNOMED-CT search terms. To pilot the supply of relevant information resources in response to clinically coded requests, using RSS syndication for transmission between web servers. Our syndicate partner provided a list of CHD SNOMED-CT terms to its end-users, a list which was coded according to UMLS specifications. When the end-user requested relevant information resources, this request was relayed from our syndicate partner's web server to the PCEL web server. The relevant resources were retrieved from the PCEL MySQL database. This database is accessed using a server side scripting language (PHP), which enables the production of dynamic RSS feeds on the basis of Source Asserted Identifiers (CODEs) contained in UMLS. Retrieving resources using SNOMED-CT terms using syndication can be used to build a functioning application. The process from request to display of syndicated resources took less than one second. The results of the pilot illustrate that it is possible to exchange data between servers using RSS syndication. This method could be utilised dynamically to supply digital library resources to a clinical system with SNOMED-CT data used as the standard of reference.

Mesenchymal chondrosarcoma of the orbit: CT and MRI findings

Energy Technology Data Exchange (ETDEWEB)

Yang, B.T., E-mail: cjr.yangbentao@vip.163.com [Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing (China); Wang, Y.Z.; Wang, X.Y.; Wang, Z.C. [Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing (China)

2012-04-15

Aim: To describe the computed tomography (CT) and magnetic resonance imaging (MRI) features of orbital mesenchymal chondrosarcomas (MCSs). Materials and methods: Six patients with histology-confirmed MCSs of the orbit were retrospectively reviewed. All six patients underwent CT and MRI. Imaging studies were evaluated for the following: (a) tumour location, (b) configuration, size, and margin, (c) CT attenuation and MRI signal intensity, and (d) secondary manifestations. Additionally, the time-intensity curve (TIC) of dynamic contrast-enhanced (DCE) MRI were analysed in five patients. Results: Two MCSs arose in the right orbit and four in the left orbit. Five MCSs were located in the retrobulbar intraconal space and one in the extraconal space. All the lesions displayed a lobulate configuration and had a well-defined margin. The mean maximum diameter was 25.8 mm (range 15-36 mm). On unenhanced CT, the lesions appeared isodense to grey matter in six patients, with calcifications in five. Two patients showed inhomogeneous, moderate enhancement on enhanced CT. Six MCSs appeared isointense on T1-weighted imaging and heterogeneously isointense on T2-weighted imaging. The lesions showed significantly heterogeneous contrast enhancement. Five patients had DCE MRI and the TICs showed a rapidly enhancing and rapid washout pattern (type III). The following features were also detected: compression of the extra-ocular muscle (six patients, 100%); displacement of the optic nerve (five patients, 83.3%); and encasing globe (three patients, 50%). Conclusions: A well-defined, lobulate orbital mass with calcification on CT and, marked heterogeneous enhancement and type III TIC on MRI are highly suspicious of orbital MCSs.

Position-Invariant Robust Features for Long-Term Recognition of Dynamic Outdoor Scenes

Science.gov (United States)

Kawewong, Aram; Tangruamsub, Sirinart; Hasegawa, Osamu

A novel Position-Invariant Robust Feature, designated as PIRF, is presented to address the problem of highly dynamic scene recognition. The PIRF is obtained by identifying existing local features (i.e. SIFT) that have a wide baseline visibility within a place (one place contains more than one sequential images). These wide-baseline visible features are then represented as a single PIRF, which is computed as an average of all descriptors associated with the PIRF. Particularly, PIRFs are robust against highly dynamical changes in scene: a single PIRF can be matched correctly against many features from many dynamical images. This paper also describes an approach to using these features for scene recognition. Recognition proceeds by matching an individual PIRF to a set of features from test images, with subsequent majority voting to identify a place with the highest matched PIRF. The PIRF system is trained and tested on 2000+ outdoor omnidirectional images and on COLD datasets. Despite its simplicity, PIRF offers a markedly better rate of recognition for dynamic outdoor scenes (ca. 90%) than the use of other features. Additionally, a robot navigation system based on PIRF (PIRF-Nav) can outperform other incremental topological mapping methods in terms of time (70% less) and memory. The number of PIRFs can be reduced further to reduce the time while retaining high accuracy, which makes it suitable for long-term recognition and localization.

Dynamic CT myocardial perfusion imaging: performance of 3D semi-automated evaluation software

Energy Technology Data Exchange (ETDEWEB)

Ebersberger, Ullrich [Medical University of South Carolina, Heart and Vascular Center, Charleston, SC (United States); Heart Center Munich-Bogenhausen, Department of Cardiology and Intensive Care Medicine, Munich (Germany); Marcus, Roy P.; Nikolaou, Konstantin; Bamberg, Fabian [University of Munich, Institute of Clinical Radiology, Munich (Germany); Schoepf, U.J.; Gray, J.C.; McQuiston, Andrew D. [Medical University of South Carolina, Heart and Vascular Center, Charleston, SC (United States); Lo, Gladys G. [Hong Kong Sanatorium and Hospital, Department of Diagnostic and Interventional Radiology, Hong Kong (China); Wang, Yining [Medical University of South Carolina, Heart and Vascular Center, Charleston, SC (United States); Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Department of Radiology, Beijing (China); Blanke, Philipp [Medical University of South Carolina, Heart and Vascular Center, Charleston, SC (United States); University Hospital Freiburg, Department of Diagnostic Radiology, Freiburg (Germany); Geyer, Lucas L. [Medical University of South Carolina, Heart and Vascular Center, Charleston, SC (United States); University of Munich, Institute of Clinical Radiology, Munich (Germany); Cho, Young Jun [Medical University of South Carolina, Heart and Vascular Center, Charleston, SC (United States); Konyang University College of Medicine, Department of Radiology, Daejeon (Korea, Republic of); Scheuering, Michael; Canstein, Christian [Siemens Healthcare, CT Division, Forchheim (Germany); Hoffmann, Ellen [Heart Center Munich-Bogenhausen, Department of Cardiology and Intensive Care Medicine, Munich (Germany)

2014-01-15

To evaluate the performance of three-dimensional semi-automated evaluation software for the assessment of myocardial blood flow (MBF) and blood volume (MBV) at dynamic myocardial perfusion computed tomography (CT). Volume-based software relying on marginal space learning and probabilistic boosting tree-based contour fitting was applied to CT myocardial perfusion imaging data of 37 subjects. In addition, all image data were analysed manually and both approaches were compared with SPECT findings. Study endpoints included time of analysis and conventional measures of diagnostic accuracy. Of 592 analysable segments, 42 showed perfusion defects on SPECT. Average analysis times for the manual and software-based approaches were 49.1 ± 11.2 and 16.5 ± 3.7 min respectively (P < 0.01). There was strong agreement between the two measures of interest (MBF, ICC = 0.91, and MBV, ICC = 0.88, both P < 0.01) and no significant difference in MBF/MBV with respect to diagnostic accuracy between the two approaches for both MBF and MBV for manual versus software-based approach; respectively; all comparisons P > 0.05. Three-dimensional semi-automated evaluation of dynamic myocardial perfusion CT data provides similar measures and diagnostic accuracy to manual evaluation, albeit with substantially reduced analysis times. This capability may aid the integration of this test into clinical workflows. (orig.)

CT features of legionella pneumonia, compared with streptococcal pneumonia. A collaborative study

International Nuclear Information System (INIS)

Tokuda, Hitoshi; Sakai, Fumikazu; Goto, Hajime

2007-01-01

Legionella pneumophila pneumonia (LPP) is of serious concern for chest physicians for its potential lethality and difficulty of diagnosis. In spite of widespread use of urine antigen detection method, it remains one of the most difficult-to-treat disease among community acquired pneumonia. We investigated CT images of 38 cases of LPP, comparing them with wide spread Streptococcus pneumoniae pneumonia (SPP). We find that sharply demarcated consolidation scattered in ground-glass opacity is the most striking and pathognomonic feature of LPP, which is rarely found in SPP. Bronchiolitis was not found in LPP, while it is a relatively common finding in SPP, which could be the second clue of differentiation of these two diseases. (author)

Dynamic facial expression recognition based on geometric and texture features

Science.gov (United States)

Li, Ming; Wang, Zengfu

2018-04-01

Recently, dynamic facial expression recognition in videos has attracted growing attention. In this paper, we propose a novel dynamic facial expression recognition method by using geometric and texture features. In our system, the facial landmark movements and texture variations upon pairwise images are used to perform the dynamic facial expression recognition tasks. For one facial expression sequence, pairwise images are created between the first frame and each of its subsequent frames. Integration of both geometric and texture features further enhances the representation of the facial expressions. Finally, Support Vector Machine is used for facial expression recognition. Experiments conducted on the extended Cohn-Kanade database show that our proposed method can achieve a competitive performance with other methods.

Impact of Reconstruction Algorithms on CT Radiomic Features of Pulmonary Tumors: Analysis of Intra- and Inter-Reader Variability and Inter-Reconstruction Algorithm Variability.

Science.gov (United States)

Kim, Hyungjin; Park, Chang Min; Lee, Myunghee; Park, Sang Joon; Song, Yong Sub; Lee, Jong Hyuk; Hwang, Eui Jin; Goo, Jin Mo

2016-01-01

To identify the impact of reconstruction algorithms on CT radiomic features of pulmonary tumors and to reveal and compare the intra- and inter-reader and inter-reconstruction algorithm variability of each feature. Forty-two patients (M:F = 19:23; mean age, 60.43±10.56 years) with 42 pulmonary tumors (22.56±8.51mm) underwent contrast-enhanced CT scans, which were reconstructed with filtered back projection and commercial iterative reconstruction algorithm (level 3 and 5). Two readers independently segmented the whole tumor volume. Fifteen radiomic features were extracted and compared among reconstruction algorithms. Intra- and inter-reader variability and inter-reconstruction algorithm variability were calculated using coefficients of variation (CVs) and then compared. Among the 15 features, 5 first-order tumor intensity features and 4 gray level co-occurrence matrix (GLCM)-based features showed significant differences (palgorithms. As for the variability, effective diameter, sphericity, entropy, and GLCM entropy were the most robust features (CV≤5%). Inter-reader variability was larger than intra-reader or inter-reconstruction algorithm variability in 9 features. However, for entropy, homogeneity, and 4 GLCM-based features, inter-reconstruction algorithm variability was significantly greater than inter-reader variability (palgorithms. Inter-reconstruction algorithm variability was greater than inter-reader variability for entropy, homogeneity, and GLCM-based features.

Thoracic endometriosis syndrome: CT and MRI features

International Nuclear Information System (INIS)

Rousset, P.; Rousset-Jablonski, C.; Alifano, M.; Mansuet-Lupo, A.; Buy, J.-N.; Revel, M.-P.

2014-01-01

Thoracic endometriosis is considered to be rare, but is the most frequent form of extra-abdominopelvic endometriosis. Thoracic endometriosis syndrome affects women of reproductive age. Diagnosis is mainly based on clinical findings, which can include catamenial pneumothorax and haemothorax, non-catamenial endometriosis-related pneumothorax, catamenial haemoptysis, lung nodules, and isolated catamenial chest pain. Symptoms are typically cyclical and recurrent, with a right-sided predominance. Computed tomography (CT) is the first-line imaging method, but is poorly specific; therefore, its main role is to rule out other pulmonary diseases. However, in women with a typical clinical history, some key CT findings may help to confirm this often under-diagnosed syndrome. MRI can also assist with the diagnosis, by showing signal changes typical of haemorrhage within diaphragmatic or pleural lesions

18F-Fluorodeoxyglucose PET/CT and dynamic contrast-enhanced MRI as imaging biomarkers in malignant pleural mesothelioma

OpenAIRE

Hall, D. O.; Hooper, C. E.; Searle, J.; Darby, M.; White, P.; Harvey, J. E.; Braybrooke, J. P.; Maskell, N. A.; Masani, V.; Lyburn, I. D.

2018-01-01

Purpose\\ud \\ud The purpose of this study was to compare the use of fluorine-18-fluorodeoxyglucose (18F-FDG) PET with computed tomography (CT) and dynamic contrast-enhanced (DCE) MRI to predict prognosis and monitor treatment in malignant pleural mesothelioma.\\ud \\ud Patients and methods\\ud \\ud 18F-FDG PET/CT and DCE-MRI studies carried out as part of the South West Area Mesothelioma Pemetrexed trial were used. 18F-FDG PET/CT and DCE-MRI studies were carried out before treatment, and after two...

Computed Tomography Features of Incidentally Detected Diffuse Thyroid Disease

Directory of Open Access Journals (Sweden)

Myung Ho Rho

2014-01-01

Full Text Available Objective. This study aimed to evaluate the CT features of incidentally detected DTD in the patients who underwent thyroidectomy and to assess the diagnostic accuracy of CT diagnosis. Methods. We enrolled 209 consecutive patients who received preoperative neck CT and subsequent thyroid surgery. Neck CT in each case was retrospectively investigated by a single radiologist. We evaluated the diagnostic accuracy of individual CT features and the cut-off CT criteria for detecting DTD by comparing the CT features with histopathological results. Results. Histopathological examination of the 209 cases revealed normal thyroid (n=157, Hashimoto thyroiditis (n=17, non-Hashimoto lymphocytic thyroiditis (n=34, and diffuse hyperplasia (n=1. The CT features suggestive of DTD included low attenuation, inhomogeneous attenuation, increased glandular size, lobulated margin, and inhomogeneous enhancement. ROC curve analysis revealed that CT diagnosis of DTD based on the CT classification of “3 or more” abnormal CT features was superior. When the “3 or more” CT classification was selected, the sensitivity, specificity, positive and negative predictive values, and accuracy of CT diagnosis for DTD were 55.8%, 95.5%, 80.6%, 86.7%, and 85.6%, respectively. Conclusion. Neck CT may be helpful for the detection of incidental DTD.

CT Perfusion Characteristics Identify Metastatic Sites in Liver

Directory of Open Access Journals (Sweden)

Yuan Wang

2015-01-01

Full Text Available Tissue perfusion plays a critical role in oncology because growth and migration of cancerous cells require proliferation of new blood vessels through the process of tumor angiogenesis. Computed tomography (CT perfusion is an emerging functional imaging modality that measures tissue perfusion through dynamic CT scanning following intravenous administration of contrast medium. This noninvasive technique provides a quantitative basis for assessing tumor angiogenesis. CT perfusion has been utilized on a variety of organs including lung, prostate, liver, and brain, with promising results in cancer diagnosis, disease prognostication, prediction, and treatment monitoring. In this paper, we focus on assessing the extent to which CT perfusion characteristics can be used to discriminate liver metastases from neuroendocrine tumors from normal liver tissues. The neuroendocrine liver metastases were analyzed by distributed parameter modeling to yield tissue blood flow (BF, blood volume (BV, mean transit time (MTT, permeability (PS, and hepatic arterial fraction (HAF, for tumor and normal liver. The result reveals the potential of CT perfusion as a tool for constructing biomarkers from features of the hepatic vasculature for guiding cancer detection, prognostication, and treatment selection.

Clinical studies of functional imaging of dynamic CT for chronic brain-damaged patients

International Nuclear Information System (INIS)

Inada, Haruo; Miyano, Satoshi

1995-01-01

The 311 brain-damaged patients, mostly of cerebrovascular disease (CVD) were examined by functional imaging to dynamic CT (FIDCT) at Tokyo Metropolitan Rehabilitation Hospital. The abnormal patterns of FIDCT were classified according to two categories, i.e. focal area where plain CT showed low density area (LDA), and extra-focal area where plain CT showed no abnormal findings. These patterns were diagnosed by using the two parameters, i.e. Corrected First Moment (CM) and Time to Peak (TP). Over 50% of the focal abnormal FIDCT revealed tha same area with LDA on plain CT. The extra-focal FIDCT showed various abnormal patterns, and only 11% of all the findings had no abnormalities. The correlation of the specific patterns of extra-focal FIDCT with the multiple CVD episodes was investigated, and the findings that had significant correlation were (a) delayed CM of bilateral white matter, (b) diffusely delayed TP of the affected hemisphere, and the patient group that showed no extra-focal abnormal FIDCT had significant low incidence of multiple CVD episodes. From these results, it is concluded that the high-risk group of stroke recurrence can be predicted by extra-focal findings of FIDCT. (author)

Clinical studies of functional imaging of dynamic CT for chronic brain-damaged patients

Energy Technology Data Exchange (ETDEWEB)

Inada, Haruo; Miyano, Satoshi [Jikei Univ., Tokyo (Japan). School of Medicine

1995-03-01

The 311 brain-damaged patients, mostly of cerebrovascular disease (CVD) were examined by functional imaging to dynamic CT (FIDCT) at Tokyo Metropolitan Rehabilitation Hospital. The abnormal patterns of FIDCT were classified according to two categories, i.e. focal area where plain CT showed low density area (LDA), and extra-focal area where plain CT showed no abnormal findings. These patterns were diagnosed by using the two parameters, i.e. Corrected First Moment (CM) and Time to Peak (TP). Over 50% of the focal abnormal FIDCT revealed tha same area with LDA on plain CT. The extra-focal FIDCT showed various abnormal patterns, and only 11% of all the findings had no abnormalities. The correlation of the specific patterns of extra-focal FIDCT with the multiple CVD episodes was investigated, and the findings that had significant correlation were (a) delayed CM of bilateral white matter, (b) diffusely delayed TP of the affected hemisphere, and the patient group that showed no extra-focal abnormal FIDCT had significant low incidence of multiple CVD episodes. From these results, it is concluded that the high-risk group of stroke recurrence can be predicted by extra-focal findings of FIDCT. (author).

Early dynamic imaging in 68Ga- PSMA-11 PET/CT allows discrimination of urinary bladder activity and prostate cancer lesions.

Science.gov (United States)

Uprimny, Christian; Kroiss, Alexander Stephan; Decristoforo, Clemens; Fritz, Josef; Warwitz, Boris; Scarpa, Lorenza; Roig, Llanos Geraldo; Kendler, Dorota; von Guggenberg, Elisabeth; Bektic, Jasmin; Horninger, Wolfgang; Virgolini, Irene Johanna

2017-05-01

PET/CT with 68 Ga-labelled prostate-specific membrane antigen (PSMA)-ligands has been proven to establish a promising imaging modality in the work-up of prostate cancer (PC) patients with biochemical relapse. Despite a high overall detection rate, the visualisation of local recurrence may be hampered by high physiologic tracer accumulation in the urinary bladder on whole body imaging, usually starting 60 min after injection. This study sought to verify whether early dynamic 68 Ga-PSMA-11 (HBED-CC)PET/CT can differentiate pathologic PC-related tracer uptake from physiologic tracer accumulation in the urinary bladder. Eighty consecutive PC patients referred to 68 Ga -PSMA-11 PET/CT were included in this retrospective analysis (biochemical relapse: n = 64; primary staging: n = 8; evaluation of therapy response/restaging: n = 8). In addition to whole-body PET/CT acquisition 60 min post injection early dynamic imaging of the pelvis in the first 8 min after tracer injection was performed. SUV max of pathologic lesions was calculated and time-activity curves were generated and compared to those of urinary bladder and areas of physiologic tracer uptake. A total of 55 lesions consistent with malignancy on 60 min whole body imaging exhibited also pathologic 68 Ga-PSMA-11 uptake during early dynamic imaging (prostatic bed/prostate gland: n = 27; lymph nodes: n = 12; bone: n = 16). All pathologic lesions showed tracer uptake within the first 3 min, whereas urinary bladder activity was absent within the first 3 min of dynamic imaging in all patients. Suv max was significantly higher in PC lesions in the first 6 min compared to urinary bladder accumulation (p dynamic imaging in 68 Ga-PSMA-11 PET/CT reliably enables the differentiation of pathologic tracer uptake in PC lesions from physiologic bladder accumulation. Performance of early dynamic imaging in addition to whole body imaging 60 min after tracer injection might improve the detection rate

Dynamic Contrast-Enhanced Perfusion Area-Detector CT: Preliminary Comparison of Diagnostic Performance for N Stage Assessment With FDG PET/CT in Non-Small Cell Lung Cancer.

Science.gov (United States)

Ohno, Yoshiharu; Fujisawa, Yasuko; Sugihara, Naoki; Kishida, Yuji; Seki, Shinichiro; Koyama, Hisanobu; Yoshikawa, Takeshi

2017-11-01

The objective of our study was to directly compare the capability of dynamic first-pass contrast-enhanced (CE) perfusion area-detector CT (ADCT) and FDG PET/CT for differentiation of metastatic from nonmetastatic lymph nodes and assessment of N stage in patients with non-small cell lung carcinoma (NSCLC). Seventy-seven consecutive patients, 45 men (mean age ± SD, 70.4 ± 5.9 years) and 32 women (71.2 ± 7.7 years), underwent dynamic first-pass CE-perfusion ADCT at two or three different positions for covering the entire thorax, FDG PET/CT, surgical treatment, and pathologic examination. From all ADCT data for each of the subjects, a whole-chest perfusion map was computationally generated using the dual- and single-input maximum slope and Patlak plot methods. For quantitative N stage assessment, perfusion parameters and the maximum standardized uptake value (SUV max ) for each lymph node were determined by measuring the relevant ROI. ROC curve analyses were performed for comparing the diagnostic capability of each of the methods on a per-node basis. N stages evaluated by each of the indexes were then statistically compared with the final pathologic diagnosis by means of chi-square and kappa statistics. The area under the ROC curve (A z ) values of systemic arterial perfusion (A z = 0.89), permeability surface (A z = 0.78), and SUV max (A z = 0.85) were significantly larger than the A z values of total perfusion (A z = 0.70, p Dynamic first-pass CE-perfusion ADCT is as useful as FDG PET/CT for the differentiation of metastatic from nonmetastatic lymph nodes and assessment of N stage in patients with NSCLC.

SU-F-R-31: Identification of Robust Normal Lung CT Texture Features for the Prediction of Radiation-Induced Lung Disease

Energy Technology Data Exchange (ETDEWEB)

Choi, W; Riyahi, S; Lu, W [University of Maryland School of Medicine, Baltimore, MD (United States)

2016-06-15

Purpose: Normal lung CT texture features have been used for the prediction of radiation-induced lung disease (radiation pneumonitis and radiation fibrosis). For these features to be clinically useful, they need to be relatively invariant (robust) to tumor size and not correlated with normal lung volume. Methods: The free-breathing CTs of 14 lung SBRT patients were studied. Different sizes of GTVs were simulated with spheres placed at the upper lobe and lower lobe respectively in the normal lung (contralateral to tumor). 27 texture features (9 from intensity histogram, 8 from grey-level co-occurrence matrix [GLCM] and 10 from grey-level run-length matrix [GLRM]) were extracted from [normal lung-GTV]. To measure the variability of a feature F, the relative difference D=|Fref -Fsim|/Fref*100% was calculated, where Fref was for the entire normal lung and Fsim was for [normal lung-GTV]. A feature was considered as robust if the largest non-outlier (Q3+1.5*IQR) D was less than 5%, and considered as not correlated with normal lung volume when their Pearson correlation was lower than 0.50. Results: Only 11 features were robust. All first-order intensity-histogram features (mean, max, etc.) were robust, while most higher-order features (skewness, kurtosis, etc.) were unrobust. Only two of the GLCM and four of the GLRM features were robust. Larger GTV resulted greater feature variation, this was particularly true for unrobust features. All robust features were not correlated with normal lung volume while three unrobust features showed high correlation. Excessive variations were observed in two low grey-level run features and were later identified to be from one patient with local lung diseases (atelectasis) in the normal lung. There was no dependence on GTV location. Conclusion: We identified 11 robust normal lung CT texture features that can be further examined for the prediction of radiation-induced lung disease. Interestingly, low grey-level run features identified normal

CT and MR features of the intracranial Schwannomas

International Nuclear Information System (INIS)

Jung, So Lyung; Ro, Hee Jeong; Lee, Hong Jae; Jung, Seung Eun; Byun, Jae Young; Yang, Il Kwon; Lee, Han Jin; Choi, Kyu Ho; Kim, Jong Woo; Shinn, Kyung Sub

1996-01-01

To evaluate CT and MR findings of the intracranial schwannomas arising from variable cranial nerves. The authors retrospectively analyzed CT (n=21) and MR (n=15) findings of 24 cases in 23 patients (M : 7, F : 16) who had suffered from surgically-proven intracranial schwannomas over the previous five years. Schwannomas arose from the acoustic nerve(n=18), the trigeminal nerve(n=2), the glossopha-ryngeal-vagal-accessory nerve complex (n=2), and the olfactory nerve(n=1). Intracranial schwannomas were well defined, ,lobulated and inhomogeneously or homogeneously enhancing masses on CT and MR, and were located along the course of the specific cranial nerve. Acoustic schwannomas involved both the internal auditory canal(IAC) and the cerebellopontive angle(CPA) in 14 case, the IAC in three, and the SPA in two. Two trigeminal schwannomas involved both middle and posterior cranial fossa and were in the shape of a dumbbell. One of the two schwannomas that invelved lower cranial nerve complex(9-11th) was located in the medullary cistern and jugular foramen ; the other was located in the central posterior cranial fossa. A case of olfactory schwannoma was located in the right cribriform plate. The precontrast CT scan showed low density in 13 cases (62%), isodensity in seven(33%) and high density in one(5%). on postcontrast CT scan, enhancement was seen in 20 cases(95%). Of the 15 cases with MR, 2 had low signal intensity on T1 weighted image and 14 had high signal intensity on T2 weighted image. MR imaging after Gd-DTPA infusion showed enhancement in 14 cases. Enhancement was inhomogeneous in 14 cases on CT and in 13 on MR. Of 24 cases, intratumoral necrosis was seen in 19, ring enhancement in five and severe cystic change in one. Other findings were in tratumoral calcification (21%), hemorrhage(8%), pressure bony erosion(70.8%), midline shift(58%), peritumoral edema(29%) and hydrocephalus(33%). On MR, there was in all 15 cases a peritumoral low signal intensity rim on T1-and

Aquilion ONE / ViSION Edition CT scanner realizing 3D dynamic observation with low-dose scanning

International Nuclear Information System (INIS)

Kazama, Masahiro; Saito, Yasuo

2015-01-01

Computed tomography (CT) scanners have been continuously advancing as essential diagnostic imaging equipment for the diagnosis and treatment of a variety of diseases, including the three major disease classes of cerebrovascular disease, cardiovascular disease, and cancer. Through the development of helical CT scanners and multislice CT scanners, Toshiba Medical Systems Corporation has developed the Aquilion ONE, a CT scanner with a scanning range of up to 160 mm per rotation that can obtain three-dimensional (3D) images of the brain, heart, and other organs in a single rotation. We have now developed the Aquilion ONE / ViSION Edition, a next-generation 320-row multislice CT scanner incorporating the latest technologies that achieves a shorter scanning time and significant reduction in dose compared with conventional products. This product with its low-dose scanning technology will contribute to the practical realization of new diagnosis and treatment modalities employing four-dimensional (4D) data based on 3D dynamic observations through continuous rotations. (author)

Internal respiratory surrogate in multislice 4D CT using a combination of Fourier transform and anatomical features

International Nuclear Information System (INIS)

Hui, Cheukkai; Suh, Yelin; Robertson, Daniel; Beddar, Sam; Pan, Tinsu; Das, Prajnan; Crane, Christopher H.

2015-01-01

Purpose: The purpose of this study was to develop a novel algorithm to create a robust internal respiratory signal (IRS) for retrospective sorting of four-dimensional (4D) computed tomography (CT) images. Methods: The proposed algorithm combines information from the Fourier transform of the CT images and from internal anatomical features to form the IRS. The algorithm first extracts potential respiratory signals from low-frequency components in the Fourier space and selected anatomical features in the image space. A clustering algorithm then constructs groups of potential respiratory signals with similar temporal oscillation patterns. The clustered group with the largest number of similar signals is chosen to form the final IRS. To evaluate the performance of the proposed algorithm, the IRS was computed and compared with the external respiratory signal from the real-time position management (RPM) system on 80 patients. Results: In 72 (90%) of the 4D CT data sets tested, the IRS computed by the authors’ proposed algorithm matched with the RPM signal based on their normalized cross correlation. For these data sets with matching respiratory signals, the average difference between the end inspiration times (Δt ins ) in the IRS and RPM signal was 0.11 s, and only 2.1% of Δt ins were more than 0.5 s apart. In the eight (10%) 4D CT data sets in which the IRS and the RPM signal did not match, the average Δt ins was 0.73 s in the nonmatching couch positions, and 35.4% of them had a Δt ins greater than 0.5 s. At couch positions in which IRS did not match the RPM signal, a correlation-based metric indicated poorer matching of neighboring couch positions in the RPM-sorted images. This implied that, when IRS did not match the RPM signal, the images sorted using the IRS showed fewer artifacts than the clinical images sorted using the RPM signal. Conclusions: The authors’ proposed algorithm can generate robust IRSs that can be used for retrospective sorting of 4D CT data

Internal respiratory surrogate in multislice 4D CT using a combination of Fourier transform and anatomical features

Energy Technology Data Exchange (ETDEWEB)

Hui, Cheukkai; Suh, Yelin [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Robertson, Daniel; Beddar, Sam, E-mail: abeddar@mdanderson.org [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and Department of Radiation Physics, The University of Texas Graduate School of Biomedical Sciences, Houston, Texas 77030 (United States); Pan, Tinsu [Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and Department of Imaging Physics, The University of Texas Graduate School of Biomedical Sciences, Houston, Texas 77030 (United States); Das, Prajnan; Crane, Christopher H. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

2015-07-15

Purpose: The purpose of this study was to develop a novel algorithm to create a robust internal respiratory signal (IRS) for retrospective sorting of four-dimensional (4D) computed tomography (CT) images. Methods: The proposed algorithm combines information from the Fourier transform of the CT images and from internal anatomical features to form the IRS. The algorithm first extracts potential respiratory signals from low-frequency components in the Fourier space and selected anatomical features in the image space. A clustering algorithm then constructs groups of potential respiratory signals with similar temporal oscillation patterns. The clustered group with the largest number of similar signals is chosen to form the final IRS. To evaluate the performance of the proposed algorithm, the IRS was computed and compared with the external respiratory signal from the real-time position management (RPM) system on 80 patients. Results: In 72 (90%) of the 4D CT data sets tested, the IRS computed by the authors’ proposed algorithm matched with the RPM signal based on their normalized cross correlation. For these data sets with matching respiratory signals, the average difference between the end inspiration times (Δt{sub ins}) in the IRS and RPM signal was 0.11 s, and only 2.1% of Δt{sub ins} were more than 0.5 s apart. In the eight (10%) 4D CT data sets in which the IRS and the RPM signal did not match, the average Δt{sub ins} was 0.73 s in the nonmatching couch positions, and 35.4% of them had a Δt{sub ins} greater than 0.5 s. At couch positions in which IRS did not match the RPM signal, a correlation-based metric indicated poorer matching of neighboring couch positions in the RPM-sorted images. This implied that, when IRS did not match the RPM signal, the images sorted using the IRS showed fewer artifacts than the clinical images sorted using the RPM signal. Conclusions: The authors’ proposed algorithm can generate robust IRSs that can be used for retrospective

Volumetric dynamic contrast enhanced Computed Tomography (DCE-CT) for preoperative assessment of the vascularity of spinal metastases

DEFF Research Database (Denmark)

Lauridsen, Carsten Ammitzbøl

Purpose To investigate the feasibility of measuring and grading the vascularity of spinal metastases using dynamic contrast enhanced CT (DCE-CT). Materials and methods Prior to surgical treatment of symptomatic metastatic spinal cord compression, 20 patients were examined using DCE-CT. The 320......–detector row CT scanner allowed a volumetric acquisition over a range of 16 cm, covering three to four vertebrae. Image analysis was performed at a dedicated workstation, encompassing quantitative and qualitative measurement of the arterial flow (AF) in mL/min/100mL of the vertebrae. The perfusion values...... were analysed using a single input, maximum slope model. The AF assessed by DCE-CT of affected and non-affected vertebrae will be compared, and furthermore, the correlation between AF and intraoperative blood loss will be examined. Results Preliminary results for 5 patients: In two patients the AF...

Use of dynamic CT in acute respiratory distress syndrome (ARDS) with comparison of positive and negative pressure ventilation

Energy Technology Data Exchange (ETDEWEB)

Helm, Emma; Babyn, Paul [Hospital for Sick Children, Department of Diagnostic Imaging, Toronto (Canada); Talakoub, Omid; Alirezaie, Javad [Ryerson University, Department of Electrical and Computer Engineering, Toronto, ON (Canada); Grasso, Francesco; Engelberts, Doreen; Kavanagh, Brian P. [Hospital for Sick Children and the University of Toronto, Departments of Anesthesia and Critical Care Medicine and the Program in Pulmonary and Experimental Medicine, Toronto (Canada)

2009-01-15

Negative pressure ventilation via an external device ('iron lung') has the potential to provide better oxygenation with reduced barotrauma in patients with ARDS. This study was designed to see if oxygenation differences between positive and negative ventilation could be explained by CT. Six anaesthetized rabbits had ARDS induced by repeated saline lavage. Rabbits were ventilated with positive pressure ventilation (PPV) and negative pressure ventilation (NPV) in turn. Dynamic CT images were acquired over the respiratory cycle. A computer-aided method was used to segment the lung and calculate the range of CT densities within each slice. Volumes of ventilated lung and atelectatic lung were measured over the respiratory cycle. NPV was associated with an increased percentage of ventilated lung and decreased percentage of atelectatic lung. The most significant differences in ventilation and atelectasis were seen at mid-inspiration and mid-expiration (ventilated lung NPV=61%, ventilated lung PPV=47%, p<0.001; atelectatic lung NPV=10%, atelectatic lung PPV 19%, p<0.001). Aeration differences were not significant at end-inspiration. Dynamic CT can show differences in lung aeration between positive and negative ventilation in ARDS. These differences would not be appreciated if only static breath-hold CT was used. (orig.)

High throughput static and dynamic small animal imaging using clinical PET/CT: potential preclinical applications

International Nuclear Information System (INIS)

Aide, Nicolas; Desmonts, Cedric; Agostini, Denis; Bardet, Stephane; Bouvard, Gerard; Beauregard, Jean-Mathieu; Roselt, Peter; Neels, Oliver; Beyer, Thomas; Kinross, Kathryn; Hicks, Rodney J.

2010-01-01

The objective of the study was to evaluate state-of-the-art clinical PET/CT technology in performing static and dynamic imaging of several mice simultaneously. A mouse-sized phantom was imaged mimicking simultaneous imaging of three mice with computation of recovery coefficients (RCs) and spillover ratios (SORs). Fifteen mice harbouring abdominal or subcutaneous tumours were imaged on clinical PET/CT with point spread function (PSF) reconstruction after injection of [18F]fluorodeoxyglucose or [18F]fluorothymidine. Three of these mice were imaged alone and simultaneously at radial positions -5, 0 and 5 cm. The remaining 12 tumour-bearing mice were imaged in groups of 3 to establish the quantitative accuracy of PET data using ex vivo gamma counting as the reference. Finally, a dynamic scan was performed in three mice simultaneously after the injection of 68 Ga-ethylenediaminetetraacetic acid (EDTA). For typical lesion sizes of 7-8 mm phantom experiments indicated RCs of 0.42 and 0.76 for ordered subsets expectation maximization (OSEM) and PSF reconstruction, respectively. For PSF reconstruction, SOR air and SOR water were 5.3 and 7.5%, respectively. A strong correlation (r 2 = 0.97, p 2 = 0.98; slope = 0.89, p 2 = 0.96; slope = 0.62, p 68 Ga-EDTA dynamic acquisition. New generation clinical PET/CT can be used for simultaneous imaging of multiple small animals in experiments requiring high throughput and where a dedicated small animal PET system is not available. (orig.)

Ventilation abnormalities in obstructive airways disorder. Detection with pulmonary dynamic densitometry by means of spinal CT versus dynamic Xe-133 SPECT

International Nuclear Information System (INIS)

Suga, Kazuyoshi; Nishigauchi, Kazuya; Kume, Norihiko; Takana, Katsuyuki; Koike, Shinji; Shimizu, Kensaku; Matsunaga, Naofumi

1999-01-01

The usefulness of pulmonary dynamic densitometry (PDD) acquired by spiral computed tomography (CT) to detect ventilation abnormalities in obstructive airway disorders was evaluated in comparison with dynamic xenon-133 (Xe-133) SPECT. Eight-second, continuous spiral CT scan was performed over 2-3 respiratory cycles in six healthy volunteers, 19 patients with airways disorder, and six patients with restrictive lung disease. The data set were reconstructed as 36 one-second temporally overlapping images at 0.2-second intervals, and regional PDD curves were displayed. Regional ventilation was assessed by Xe-133 clearance-time on Xe-133 SPECT. Normal lungs showed smooth, sinusoidal PDD curves with maximal amplitude in lung attenuation change (MALAC) of 54.9+24.5 HU; whereas, obstructive airways disorders with prolonged Xe-133 clearance showed significantly diminished MALAC (31.6+20.1 HU, P<0.0001), accompanied by irregularity, asynchronous phase, and deterioration of normal ventral-to-dorsal gradients in MALAC and lung attenuation. Restrictive diseases without prolonged Xe-133 clearance did not show statistically significant reduction in MALAC. In total 251 lung regions, regional MALAC correlated inversely with Xe-133 clearance-time (r=842). PDD acquired by spiral CT is acceptable for detecting ventilation abnormalities in obstructive airways disorder. (author)

Coronary CT angiography

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Dewey, Marc [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie

2009-07-01

Coronary CT angiography has attained increasing scientific attention at academic institutions and has become a highly accurate diagnostic modality. Extending this knowledge into a practice setting is the purpose of 'Coronary CT Angiography'. This book will assist you in integrating cardiac CT into your daily practice, while also giving an overview of the current technical status and applications. The specific features of scanners from all four main vendors are also presented providing an objective overview of noninvasive coronary angiography using CT. (orig.)

Diagnosing pancreatic cancer: the role of percutaneous biopsy and CT

International Nuclear Information System (INIS)

Amin, Z.; Theis, B.; Russell, R.C.G.; House, C.; Novelli, M.; Lees, W.R.

2006-01-01

Aims: To determine the sensitivity and complications of percutaneous biopsy of pancreatic masses, and whether typical computed tomography (CT) features of adenocarcinoma can reliably predict this diagnosis. Materials and methods: A 5 year retrospective analysis of percutaneous core biopsies of pancreatic masses and their CT features was undertaken. Data were retrieved from surgical/pathology databases; medical records and CT reports and images. Results: Three hundred and three patients underwent 372 biopsies; 56 of 87 patients had repeat biopsies. Malignancy was diagnosed in 276 patients, with ductal adenocarcinoma in 259 (85%). Final sensitivity of percutaneous biopsy for diagnosing pancreatic neoplasms was 90%; for repeat biopsy it was 87%. Complications occurred in 17 (4.6%) patients, in three of whom the complications were major (1%): one abscess, one duodenal perforation, one large retroperitoneal bleed. CT features typical of ductal adenocarcinoma were: hypovascular pancreatic mass with bile and/or pancreatic duct dilatation. Atypical CT features were: isodense or hypervascular mass, calcification, non-dilated ducts, cystic change, and extensive lymphadenopathy. Defining typical CT features of adenocarcinoma as true-positives, CT had a sensitivity of 68%, specificity of 95%, positive predictive value (PPV) of 98%, and negative predictive value of 41% for diagnosing pancreatic adenocarcinoma. Conclusion: Final sensitivity of percutaneous biopsy for establishing the diagnosis was 90%. CT features typical of pancreatic adenocarcinoma had high specificity and PPV. On some occasions, especially in frail patients with co-morbidity, it might be reasonable to assume a diagnosis of pancreatic cancer if CT features are typical, and biopsy only if CT shows atypical features

Diagnosing pancreatic cancer: the role of percutaneous biopsy and CT

Energy Technology Data Exchange (ETDEWEB)

Amin, Z.; Theis, B.; Russell, R.C.G.; House, C.; Novelli, M.; Lees, W.R

2006-12-15

Aims: To determine the sensitivity and complications of percutaneous biopsy of pancreatic masses, and whether typical computed tomography (CT) features of adenocarcinoma can reliably predict this diagnosis. Materials and methods: A 5 year retrospective analysis of percutaneous core biopsies of pancreatic masses and their CT features was undertaken. Data were retrieved from surgical/pathology databases; medical records and CT reports and images. Results: Three hundred and three patients underwent 372 biopsies; 56 of 87 patients had repeat biopsies. Malignancy was diagnosed in 276 patients, with ductal adenocarcinoma in 259 (85%). Final sensitivity of percutaneous biopsy for diagnosing pancreatic neoplasms was 90%; for repeat biopsy it was 87%. Complications occurred in 17 (4.6%) patients, in three of whom the complications were major (1%): one abscess, one duodenal perforation, one large retroperitoneal bleed. CT features typical of ductal adenocarcinoma were: hypovascular pancreatic mass with bile and/or pancreatic duct dilatation. Atypical CT features were: isodense or hypervascular mass, calcification, non-dilated ducts, cystic change, and extensive lymphadenopathy. Defining typical CT features of adenocarcinoma as true-positives, CT had a sensitivity of 68%, specificity of 95%, positive predictive value (PPV) of 98%, and negative predictive value of 41% for diagnosing pancreatic adenocarcinoma. Conclusion: Final sensitivity of percutaneous biopsy for establishing the diagnosis was 90%. CT features typical of pancreatic adenocarcinoma had high specificity and PPV. On some occasions, especially in frail patients with co-morbidity, it might be reasonable to assume a diagnosis of pancreatic cancer if CT features are typical, and biopsy only if CT shows atypical features.

Imaging of head and neck tumors -- methods: CT, spiral-CT, multislice-spiral-CT

International Nuclear Information System (INIS)

Baum, Ulrich; Greess, Holger; Lell, Michael; Noemayr, Anton; Lenz, Martin

2000-01-01

Spiral-CT is standard for imaging neck tumors. In correspondence with other groups we routinely use spiral-CT with thin slices (3 mm), a pitch of 1.3-1.5 and an overlapping reconstruction increment (2-3 mm). In patients with dental fillings a short additional spiral parallel to the corpus of the mandible reduces artifacts behind the dental arches and improves the diagnostic value of CT. For the assessment of the base of the skull, the orbital floor, the palate and paranasal sinuses an additional examination in the coronal plane is helpful. Secondary coronal reconstructions of axial scans are helpful in the evaluation of the crossing of the midline by small tumors of the tongue base or palate. For an optimal vascular or tissue contrast a sufficient volume of contrast medium and a start delay greater than 70-80 s are necessary. In our opinion the best results can be achieved with a volume of 150 ml, a flow of 2.5 ml/s and a start delay of 80 s. Dynamic enhanced CT is only necessary in some special cases. There is clear indication for dynamic enhanced CT where a glomus tumor is suspected. Additional functional CT imaging during i-phonation and/or Valsalva's maneuver are of great importance to prove vocal cords mobility. Therefore, imaging during i-phonation is an elemental part of every thorough examination of the hypopharynx and larynx region. Multislice-spiral-CT allows almost isotropic imaging of the head and neck region and improves the assessment of tumor spread and lymph node metastases in arbitrary oblique planes. Thin structures (the base of the skull, the orbital floor, the hard palate) as well as the floor of the mouth can be evaluated sufficiently with multiplanar reformations. Usually, additional coronal scanning is not necessary with multislice-spiral-CT. Multislice-spiral-CT is especially advantageous in defining the critical relationships of tumor and lymph node metastases and for functional imaging of the hypopharynx and larynx not only in the

Characterization of tumor heterogeneity using dynamic contrast enhanced CT and FDG-PET in non-small cell lung cancer

International Nuclear Information System (INIS)

Elmpt, Wouter van; Das, Marco; Hüllner, Martin; Sharifi, Hoda; Zegers, Catharina M.L.; Reymen, Bart; Lambin, Philippe; Wildberger, Joachim E.; Troost, Esther G.C.; Veit-Haibach, Patrick; De Ruysscher, Dirk

2013-01-01

Purpose: Dynamic contrast-enhanced CT (DCE-CT) quantifies vasculature properties of tumors, whereas static FDG-PET/CT defines metabolic activity. Both imaging modalities are capable of showing intra-tumor heterogeneity. We investigated differences in vasculature properties within primary non-small cell lung cancer (NSCLC) tumors measured by DCE-CT and metabolic activity from FDG-PET/CT. Methods: Thirty three NSCLC patients were analyzed prior to treatment. FDG-PET/CT and DCE-CT were co-registered. The tumor was delineated and metabolic activity was segmented on the FDG-PET/CT in two regions: low (<50% maximum SUV) and high (⩾50% maximum SUV) metabolic uptake. Blood flow, blood volume and permeability were calculated using a maximum slope, deconvolution algorithm and a Patlak model. Correlations were assessed between perfusion parameters for the regions of interest. Results: DCE-CT provided additional information on vasculature and tumor heterogeneity that was not correlated to metabolic tumor activity. There was no significant difference between low and high metabolic active regions for any of the DCE-CT parameters. Furthermore, only moderate correlations between maximum SUV and DCE-CT parameters were observed. Conclusions: No direct correlation was observed between FDG-uptake and parameters extracted from DCE-CT. DCE-CT may provide complementary information to the characterization of primary NSCLC tumors over FDG-PET/CT imaging

Vehicle Unsteady Dynamics Characteristics Based on Tire and Road Features

Directory of Open Access Journals (Sweden)

Bin Ma

2013-01-01

Full Text Available During automotive related accidents, tire and road play an important role in vehicle unsteady dynamics as they have a significant impact on the sliding friction. The calculation of the rubber viscoelastic energy loss modulus and the true contact area model is improved based on the true contact area and the rubber viscoelastic theory. A 10 DOF full vehicle dynamic model in consideration of the kinetic sliding friction coefficient which has good accuracy and reality is developed. The stability test is carried out to evaluate the effectiveness of the model, and the simulation test is done in MATLAB to analyze the impact of tire feature and road self-affine characteristics on the sport utility vehicle (SUV unsteady dynamics under different weights. The findings show that it is a great significance to analyze the SUV dynamics equipped with different tire on different roads, which may provide useful insights into solving the explicit-implicit features of tire prints in systematically and designing active safety systems.

Where Does It Lead? Imaging Features of Cardiovascular Implantable Electronic Devices on Chest Radiograph and CT

Energy Technology Data Exchange (ETDEWEB)

Lanzman, Rotem S.; Blondin, Dirk; Furst, Gunter; Scherer, Axel; R Miese, Falk; Kroepil, Patric [University of Duesseldorf, Medical Faculty, 40225 Duesseldorf (Germany); Winter, Joachim [University Hospital Duesseldorf, 40225 Duesseldorf (Germany); Abbara, Suhny [Massachusetts General Hospital, Boston, MA (US)

2011-10-15

Pacemakers and implantable cardioverter defibrillators (ICDs) are being increasingly employed in patients suffering from cardiac rhythm disturbances. The principal objective of this article is to familiarize radiologists with pacemakers and ICDs on chest radiographs and CT scans. Therefore, the preferred lead positions according to pacemaker types and anatomic variants are introduced in this study. Additionally, the imaging features of incorrect lead positions and defects, as well as complications subsequent to pacemaker implantation are demonstrated herein.

Where Does It Lead? Imaging Features of Cardiovascular Implantable Electronic Devices on Chest Radiograph and CT

International Nuclear Information System (INIS)

Lanzman, Rotem S.; Blondin, Dirk; Furst, Gunter; Scherer, Axel; R Miese, Falk; Kroepil, Patric; Winter, Joachim; Abbara, Suhny

2011-01-01

Pacemakers and implantable cardioverter defibrillators (ICDs) are being increasingly employed in patients suffering from cardiac rhythm disturbances. The principal objective of this article is to familiarize radiologists with pacemakers and ICDs on chest radiographs and CT scans. Therefore, the preferred lead positions according to pacemaker types and anatomic variants are introduced in this study. Additionally, the imaging features of incorrect lead positions and defects, as well as complications subsequent to pacemaker implantation are demonstrated herein.

Correlative investigation of dynamic contrast CT and positron emission tomography with 18-fluorodeoxy glucose standardized uptake value in non-small cell lung cancer

International Nuclear Information System (INIS)

Ding Qiyong; Hua Yanqing; Zhu Feng; Mao Dingbiao; Ge Xiaojun; Zhang Guozhen; Guan Yihui; Zhao Jun

2005-01-01

Objective: To explore the correlation of dynamic enhanced CT attenuation and 18-fluorodeoxy glucose ( 18 F-FDG) standardized uptake value (SUV) in non-small cell lung cancer (NSCLC). Methods: Twenty-eight NSCLC patients and 13 patients with benign nodules (28 male, 13 female; age range 15-79 years, median 57 years; the diameter range from 0.8-4.0 cm, mean 2.2 cm) were examined on Siemens biograph sensation 16 PET-CT with 18 F-FDG. Dynamic enhanced CT scan was performed on Siemens sensation 16 PET-CT or 16 slice CT in 23 patients and other 18 patients had the results of dynamic CT from other hospitals. The mean CT attenuation of ROI on precontrast and postcontrast multi-phase images, the maxium and average SUV of 18 F-FDG were respectively measured. The correlation between the peak attenuation (A PA ) and SUV was analyzed with pearson correlation coefficient test. Results: The CT A PA between NSCLC and benign nodules had no significance difference (t=1.374, P=0.189). The difference of maximum and average SUV between NSCLC and benignity were significant (t=-3.972, P PA , maximum SUV (7.23 ± 4.38), and average SUV (4.93±3.53) (r=-0.040, P=0.839 and r=0.056, P=0.778). Conclusion: There is no correlation between A PA and SUV in NSCLC. SUV is probably not suitable for the evaluation of the effects of anti-angiogenesis therapy. (authors)

Clinical role of early dynamic FDG-PET/CT for the evaluation of renal cell carcinoma.

Science.gov (United States)

Nakajima, Reiko; Abe, Koichiro; Kondo, Tsunenori; Tanabe, Kazunari; Sakai, Shuji

2016-06-01

We studied the usefulness of early dynamic (ED) and whole-body (WB) FDG-PET/CT for the evaluation of renal cell carcinoma (RCC). One hundred patients with 107 tumours underwent kidney ED and WB FDG-PET/CT. We visually and semiquantitatively evaluated the FDG accumulation in RCCs in the ED and WB phases, and compared the accumulation values with regard to histological type (clear cell carcinoma [CCC] vs. non-clear cell carcinoma [N-CCC]), the TNM stage (high stage [3-4] vs. low stage [1-2]), the Fuhrman grade (high grade [3-4] vs. low grade [1-2]) and presence versus absence of venous (V) and lymphatic (Ly) invasion. In the ED phase, visual evaluation revealed no significant differences in FDG accumulation in terms of each item. However, the maximum standardized uptake value and tumour-to-normal tissue ratios were significantly higher in the CCCs compared to the N-CCCs (p PET/CT is a useful tool for the evaluation of RCCs. • ED and WB FDG-PET/ CT helps to assess patients with RCC • ED FDG-PET/CT enabled differentiation between CCC and N-CCC • FDG accumulation in the WB phase reflects tumour aggressiveness • Management of RCC is improved by ED and WB FDG-PET/CT.

A Registration Method Based on Contour Point Cloud for 3D Whole-Body PET and CT Images

Directory of Open Access Journals (Sweden)

Zhiying Song

2017-01-01

Full Text Available The PET and CT fusion image, combining the anatomical and functional information, has important clinical meaning. An effective registration of PET and CT images is the basis of image fusion. This paper presents a multithread registration method based on contour point cloud for 3D whole-body PET and CT images. Firstly, a geometric feature-based segmentation (GFS method and a dynamic threshold denoising (DTD method are creatively proposed to preprocess CT and PET images, respectively. Next, a new automated trunk slices extraction method is presented for extracting feature point clouds. Finally, the multithread Iterative Closet Point is adopted to drive an affine transform. We compare our method with a multiresolution registration method based on Mattes Mutual Information on 13 pairs (246~286 slices per pair of 3D whole-body PET and CT data. Experimental results demonstrate the registration effectiveness of our method with lower negative normalization correlation (NC = −0.933 on feature images and less Euclidean distance error (ED = 2.826 on landmark points, outperforming the source data (NC = −0.496, ED = 25.847 and the compared method (NC = −0.614, ED = 16.085. Moreover, our method is about ten times faster than the compared one.

Do SNOMED CT Relationships Qualify?

NARCIS (Netherlands)

Cornet, Ronald

2008-01-01

An important feature of SNOMED CT is post-coordination, which is enabled as SNOMED CT specifies refinability of target concepts of relationships. In this paper the use of refinable relationships in SNOMED CT is analysed, and the interplay between refinable and defining relationships. Refinability is

Dynamic computed tomography (CT) in the rat kidney and application to acute renal failure models

International Nuclear Information System (INIS)

Ishikawa, Isao; Saito, Tadashi; Ishii, Hirofumi; Bansho, Junichi; Koyama, Yukinori; Tobita, Akira

1995-01-01

Renal dynamic CT scanning is suitable for determining the excretion of contrast medium in the cortex and medulla of the kidney, which is valuable for understanding the pathogenesis of disease processes in various conditions. This form of scanning would be convenient for use, if a method of application to the rat kidney were available. Therefore, we developed a method of applying renal dynamic CT to rats and evaluated the cortical and medullary curves, e.g., the corticomedullary junction time which is correlated to creatinine clearance, in various rat models of acute renal failure. The rat was placed in a 10deg oblique position and a bilateral hilar slice was obtained before and 5, 10, 15, 20, 25, 30, 40, 50, 60, 80, 100, 120, 140, 160 and 180 sec after administering 0.5 ml of contrast medium using Somatom DR. The width of the slice was 4 mm and the scan time was 3 sec. The corticomedullary junction time in normal rats was 23.0±10.5 sec, the peak value of the cortical curve was 286.3±76.7 Hounsfield Unit (HU) and the peak value of the medullary curve was 390.1±66.2 HU. Corticomedullary junction time after exposure of the kidney was prolonged compared to that of the unexposed kidney. In rats with acute renal failure, the excretion pattern of contrast medium was similar in both the glycerol- and HgCl2-induced acute renal failure models. The peak values of the cortical curve were maintained three hours after a clamp was placed at the hilar region of the kidney for one hour, and the peak values of the medullary curve were maintained during the administration of 10μg/kg/min of angiotensin II. Dynamic CT curves in the acute renal failure models examined were slightly different from those in human acute renal failure. These results suggest that rats do not provide an ideal model for human acute renal failure. However, the application of dynamic CT to the rat kidney models was valuable for estimating the pathogenesis of various human kidney diseases. (author)

[Osteo-odonto-kerato-prosthesis. Radiographic, CT and MR features].

Science.gov (United States)

Bellelli, A; Avitto, A; Liberali, M; Iannetti, F; Iannetti, L; David, V

2001-09-01

Osteo-odonto-keratoprosthesis, a complex eye surgery technique devised by Strampelli, provides a valuable opportunity to restore vision in patients with severe corneal opacification (chemical or thermal burns, bullous keratopathy, severe keratitis, consequences of perforating injuries) in whom corneal transplant or the insertion of synthetic prostheses is contraindicated because of the high risk of rejection. Successful implantation of corneal prostheses in these patients was clearly dependent on the use of perfectly biocompatible materials to support the optic. Strampelli demonstrated that thin autologous tooth sections, complete with alveolar-dental ligament fulfilled these requirements, and integrated perfectly with the eye tissues without any risk of rejection. This study aims to present the radiological aspects and postoperative outcome of 13 patients who received osteo-odonto-keratoprosthesis (bilateral in 11 cases and monolateral in 2) evaluated by plain radiography, CT and MRI. Between 1993 and 2001 we evaluated 13 patients who had undergone Strampelli's osteo-odonto-keratoprosthesis, using CT, plain radiography and MRI. All patients were examined by plain radiography; 11 patients were also examined by CT and 8 also by MRI. The time interval between surgery and the radiological evaluation ranged from 3 to 13 years with a mean follow-up of 5 years and 9 months. All patients underwent periodic clinical and imaging examinations in the post-operative period to evaluate the osteo-dental implant and to study trophism of the transplant. No post-operative complications, either cicatricial, inflammatory or of any other nature, were clinically suspected. Only two patients showed partial reabsorption of the osteo-dental lamina - evident both on plain film and CT - 10 and 12 years after surgery. Vision was restored in all the patients, with visual acuity of 10/10 in 7 cases. Plain radiography allows to correctly evaluate the position of the prosthesis and detect

Early dynamic imaging in {sup 68}Ga- PSMA-11 PET/CT allows discrimination of urinary bladder activity and prostate cancer lesions

Energy Technology Data Exchange (ETDEWEB)

Uprimny, Christian; Kroiss, Alexander Stephan; Decristoforo, Clemens; Warwitz, Boris; Scarpa, Lorenza; Roig, Llanos Geraldo; Kendler, Dorota; Guggenberg, Elisabeth von; Virgolini, Irene Johanna [Medical University Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Fritz, Josef [Medical University Innsbruck, Department for Medical Statistics, Informatics and Health Economics, Innsbruck (Austria); Bektic, Jasmin; Horninger, Wolfgang [Medical University Innsbruck, Department of Urology, Innsbruck (Austria)

2017-05-15

PET/CT with {sup 68}Ga-labelled prostate-specific membrane antigen (PSMA)-ligands has been proven to establish a promising imaging modality in the work-up of prostate cancer (PC) patients with biochemical relapse. Despite a high overall detection rate, the visualisation of local recurrence may be hampered by high physiologic tracer accumulation in the urinary bladder on whole body imaging, usually starting 60 min after injection. This study sought to verify whether early dynamic {sup 68}Ga-PSMA-11 (HBED-CC)PET/CT can differentiate pathologic PC-related tracer uptake from physiologic tracer accumulation in the urinary bladder. Eighty consecutive PC patients referred to {sup 68}Ga -PSMA-11 PET/CT were included in this retrospective analysis (biochemical relapse: n = 64; primary staging: n = 8; evaluation of therapy response/restaging: n = 8). In addition to whole-body PET/CT acquisition 60 min post injection early dynamic imaging of the pelvis in the first 8 min after tracer injection was performed. SUV{sub max} of pathologic lesions was calculated and time-activity curves were generated and compared to those of urinary bladder and areas of physiologic tracer uptake. A total of 55 lesions consistent with malignancy on 60 min whole body imaging exhibited also pathologic {sup 68}Ga-PSMA-11 uptake during early dynamic imaging (prostatic bed/prostate gland: n = 27; lymph nodes: n = 12; bone: n = 16). All pathologic lesions showed tracer uptake within the first 3 min, whereas urinary bladder activity was absent within the first 3 min of dynamic imaging in all patients. Suv{sub max} was significantly higher in PC lesions in the first 6 min compared to urinary bladder accumulation (p < 0.001). In the subgroup of PC patients with biochemical relapse the detection rate of local recurrence could be increased from 20.3 to 29.7%. Early dynamic imaging in {sup 68}Ga-PSMA-11 PET/CT reliably enables the differentiation of pathologic tracer uptake in PC lesions from physiologic

Early dynamic imaging in "6"8Ga- PSMA-11 PET/CT allows discrimination of urinary bladder activity and prostate cancer lesions

International Nuclear Information System (INIS)

Uprimny, Christian; Kroiss, Alexander Stephan; Decristoforo, Clemens; Warwitz, Boris; Scarpa, Lorenza; Roig, Llanos Geraldo; Kendler, Dorota; Guggenberg, Elisabeth von; Virgolini, Irene Johanna; Fritz, Josef; Bektic, Jasmin; Horninger, Wolfgang

2017-01-01

PET/CT with "6"8Ga-labelled prostate-specific membrane antigen (PSMA)-ligands has been proven to establish a promising imaging modality in the work-up of prostate cancer (PC) patients with biochemical relapse. Despite a high overall detection rate, the visualisation of local recurrence may be hampered by high physiologic tracer accumulation in the urinary bladder on whole body imaging, usually starting 60 min after injection. This study sought to verify whether early dynamic "6"8Ga-PSMA-11 (HBED-CC)PET/CT can differentiate pathologic PC-related tracer uptake from physiologic tracer accumulation in the urinary bladder. Eighty consecutive PC patients referred to "6"8Ga -PSMA-11 PET/CT were included in this retrospective analysis (biochemical relapse: n = 64; primary staging: n = 8; evaluation of therapy response/restaging: n = 8). In addition to whole-body PET/CT acquisition 60 min post injection early dynamic imaging of the pelvis in the first 8 min after tracer injection was performed. SUV_m_a_x of pathologic lesions was calculated and time-activity curves were generated and compared to those of urinary bladder and areas of physiologic tracer uptake. A total of 55 lesions consistent with malignancy on 60 min whole body imaging exhibited also pathologic "6"8Ga-PSMA-11 uptake during early dynamic imaging (prostatic bed/prostate gland: n = 27; lymph nodes: n = 12; bone: n = 16). All pathologic lesions showed tracer uptake within the first 3 min, whereas urinary bladder activity was absent within the first 3 min of dynamic imaging in all patients. Suv_m_a_x was significantly higher in PC lesions in the first 6 min compared to urinary bladder accumulation (p < 0.001). In the subgroup of PC patients with biochemical relapse the detection rate of local recurrence could be increased from 20.3 to 29.7%. Early dynamic imaging in "6"8Ga-PSMA-11 PET/CT reliably enables the differentiation of pathologic tracer uptake in PC lesions from physiologic bladder accumulation

Development of a dynamic quality assurance testing protocol for multisite clinical trial DCE-CT accreditation

Energy Technology Data Exchange (ETDEWEB)

Driscoll, B. [Department of Radiation Physics, Princess Margaret Cancer Center, 610 University Avenue, Toronto, Ontario M5G 2M9 (Canada); Keller, H. [Department of Radiation Physics, Princess Margaret Cancer Center, 610 University Avenue, Toronto, Ontario M5G 2M9, Canada and Department of Radiation Oncology, University of Toronto, 150 College Street, Toronto, Ontario M5S 3E2 (Canada); Jaffray, D.; Coolens, C. [Department of Radiation Physics, Princess Margaret Cancer Center, 610 University Avenue, Toronto, Ontario M5G 2M9 (Canada); Department of Radiation Oncology, University of Toronto, 150 College Street, Toronto, Ontario M5S 3E2 (Canada); Techna Institute, University Health Network, 124-100 College Street, Toronto, Ontario M5G 1L5 (Canada)

2013-08-15

Purpose: Credentialing can have an impact on whether or not a clinical trial produces useful quality data that is comparable between various institutions and scanners. With the recent increase of dynamic contrast enhanced-computed tomography (DCE-CT) usage as a companion biomarker in clinical trials, effective quality assurance, and control methods are required to ensure there is minimal deviation in the results between different scanners and protocols at various institutions. This paper attempts to address this problem by utilizing a dynamic flow imaging phantom to develop and evaluate a DCE-CT quality assurance (QA) protocol.Methods: A previously designed flow phantom, capable of producing predictable and reproducible time concentration curves from contrast injection was fully validated and then utilized to design a DCE-CT QA protocol. The QA protocol involved a set of quantitative metrics including injected and total mass error, as well as goodness of fit comparison to the known truth concentration curves. An additional region of interest (ROI) sensitivity analysis was also developed to provide additional details on intrascanner variability and determine appropriate ROI sizes for quantitative analysis. Both the QA protocol and ROI sensitivity analysis were utilized to test variations in DCE-CT results using different imaging parameters (tube voltage and current) as well as alternate reconstruction methods and imaging techniques. The developed QA protocol and ROI sensitivity analysis was then applied at three institutions that were part of clinical trial involving DCE-CT and results were compared.Results: The inherent specificity of robustness of the phantom was determined through calculation of the total intraday variability and determined to be less than 2.2 ± 1.1% (total calculated output contrast mass error) with a goodness of fit (R{sup 2}) of greater than 0.99 ± 0.0035 (n= 10). The DCE-CT QA protocol was capable of detecting significant deviations from

False Discovery Rates in PET and CT Studies with Texture Features: A Systematic Review.

Directory of Open Access Journals (Sweden)

Anastasia Chalkidou

Full Text Available A number of recent publications have proposed that a family of image-derived indices, called texture features, can predict clinical outcome in patients with cancer. However, the investigation of multiple indices on a single data set can lead to significant inflation of type-I errors. We report a systematic review of the type-I error inflation in such studies and review the evidence regarding associations between patient outcome and texture features derived from positron emission tomography (PET or computed tomography (CT images.For study identification PubMed and Scopus were searched (1/2000-9/2013 using combinations of the keywords texture, prognostic, predictive and cancer. Studies were divided into three categories according to the sources of the type-I error inflation and the use or not of an independent validation dataset. For each study, the true type-I error probability and the adjusted level of significance were estimated using the optimum cut-off approach correction, and the Benjamini-Hochberg method. To demonstrate explicitly the variable selection bias in these studies, we re-analyzed data from one of the published studies, but using 100 random variables substituted for the original image-derived indices. The significance of the random variables as potential predictors of outcome was examined using the analysis methods used in the identified studies.Fifteen studies were identified. After applying appropriate statistical corrections, an average type-I error probability of 76% (range: 34-99% was estimated with the majority of published results not reaching statistical significance. Only 3/15 studies used a validation dataset. For the 100 random variables examined, 10% proved to be significant predictors of survival when subjected to ROC and multiple hypothesis testing analysis.We found insufficient evidence to support a relationship between PET or CT texture features and patient survival. Further fit for purpose validation of these

False Discovery Rates in PET and CT Studies with Texture Features: A Systematic Review.

Science.gov (United States)

Chalkidou, Anastasia; O'Doherty, Michael J; Marsden, Paul K

2015-01-01

A number of recent publications have proposed that a family of image-derived indices, called texture features, can predict clinical outcome in patients with cancer. However, the investigation of multiple indices on a single data set can lead to significant inflation of type-I errors. We report a systematic review of the type-I error inflation in such studies and review the evidence regarding associations between patient outcome and texture features derived from positron emission tomography (PET) or computed tomography (CT) images. For study identification PubMed and Scopus were searched (1/2000-9/2013) using combinations of the keywords texture, prognostic, predictive and cancer. Studies were divided into three categories according to the sources of the type-I error inflation and the use or not of an independent validation dataset. For each study, the true type-I error probability and the adjusted level of significance were estimated using the optimum cut-off approach correction, and the Benjamini-Hochberg method. To demonstrate explicitly the variable selection bias in these studies, we re-analyzed data from one of the published studies, but using 100 random variables substituted for the original image-derived indices. The significance of the random variables as potential predictors of outcome was examined using the analysis methods used in the identified studies. Fifteen studies were identified. After applying appropriate statistical corrections, an average type-I error probability of 76% (range: 34-99%) was estimated with the majority of published results not reaching statistical significance. Only 3/15 studies used a validation dataset. For the 100 random variables examined, 10% proved to be significant predictors of survival when subjected to ROC and multiple hypothesis testing analysis. We found insufficient evidence to support a relationship between PET or CT texture features and patient survival. Further fit for purpose validation of these image

Dynamic CT in early stage of cerebral ischemia; Clinical usefulness of dynamic CT for rapid evaluation of patients considered for emergency cerebral revascularization

Energy Technology Data Exchange (ETDEWEB)

Aritake, Koichi; Sano, Keiji (Fuji Brain Inst. Hospital, Fujinomiya, Shizuoka (Japan))

1990-12-01

In the present study, we correlated collateral flow patterns derived from dynamic CT (DCT) and the evolution of cerebral infarction in patients with ischemic episodes and analyzed the efficacy of emergency cerebral revascularization (ECR) in preventing infarction. Forty-four patients, all of whom presented cerebral arterial occlusion without showing any hypodense areas on their initial CT scans, were examined. Eleven patients underwent ECR. Time-density curves (TDCs) within 239 different regions in territories of occluded arteries were derived from DCT. The degree of collateral flow and delay of circulation time were assessed, comparing peak values and peak times of TDCs on the occluded side with those in corresponding regions on the non-occluded side. Hemodynamic patterns of TDCs were classified into the following three types: Type 1 - the residual flow was considerably preserved with markedly delayed circulation time; Type 2 - the collateral flow was considerably preserved, but its circulation time was minimally or moderately delayed; and Type 3 - the residual flow was minimal or moderate with or without slowing of circulation time. In the medically-treated group, follow-up CT scans demonstrated infarction in 89% of Type 1, 6% of Type 2 and 97% of Type 3. In the surgically-treated group, infarction developed in 20% of Type 1, 0% of Type 2 and 95% of Type 3. The hemodynamic pattern map, demonstrated with the advent of the personal computer, was clinically useful in predicting the appearance and extent of infarction and judging the prognosis of patients, even immediately after the ischemic ictus. It would appear that patients whose preoperative DCT discloses a Type 1 perfusion pattern can be expected to benefit the most from ECR. (author).

CT evaluation of chronic thromboembolic pulmonary hypertension

Energy Technology Data Exchange (ETDEWEB)

Willemink, M.J. [Department of Radiology, St Antonius Hospital, Nieuwegein (Netherlands); Es, H.W. van, E-mail: h.es@antoniusziekenhuis.nl [Department of Radiology, St Antonius Hospital, Nieuwegein (Netherlands); Koobs, L. [Department of Radiology, St Antonius Hospital, Nieuwegein (Netherlands); Morshuis, W.J. [Department of Cardio-Thoracic Surgery, St Antonius Hospital, Nieuwegein (Netherlands); Snijder, R.J. [Department of Pulmonary Disease, St Antonius Hospital, Nieuwegein (Netherlands); Heesewijk, J.P.M. van [Department of Radiology, St Antonius Hospital, Nieuwegein (Netherlands)

2012-03-15

The educational objectives of this article are to provide an overview of the computed tomography (CT) findings in chronic thromboembolic pulmonary hypertension. This article reviews the key imaging findings at CT in patients with chronic thromboembolic pulmonary hypertension. After reading this article, the reader should have an improved awareness of the condition, its imaging features, and the CT imaging features associated with surgically accessible disease.

CT evaluation of chronic thromboembolic pulmonary hypertension

International Nuclear Information System (INIS)

Willemink, M.J.; Es, H.W. van; Koobs, L.; Morshuis, W.J.; Snijder, R.J.; Heesewijk, J.P.M. van

2012-01-01

The educational objectives of this article are to provide an overview of the computed tomography (CT) findings in chronic thromboembolic pulmonary hypertension. This article reviews the key imaging findings at CT in patients with chronic thromboembolic pulmonary hypertension. After reading this article, the reader should have an improved awareness of the condition, its imaging features, and the CT imaging features associated with surgically accessible disease.

[{sup 18}F]FDG PET/CT features for the molecular characterization of primary breast tumors

Energy Technology Data Exchange (ETDEWEB)

Antunovic, Lidija [Humanitas Research Hospital, Nuclear Medicine Department, Milan (Italy); Gallivanone, Francesca; Castiglioni, Isabella [National Research Council, Laboratory of Innovation and Integration in Molecular Medicine, Institute of Molecular Bioimaging and Physiology, Milan (Italy); Sollini, Martina; Kirienko, Margarita [Humanitas University, Department of Biomedical Sciences, Milan (Italy); Sagona, Andrea; Tinterri, Corrado [Humanitas Research Hospital, Breast Unit, Milan (Italy); Invento, Alessandra [Integrated University Hospital, Breast Unit, Verona (Italy); Manfrinato, Giulia [University of Milan, Residency Program in Nuclear Medicine, Milan (Italy); Chiti, Arturo [Humanitas Research Hospital, Nuclear Medicine Department, Milan (Italy); Humanitas University, Department of Biomedical Sciences, Milan (Italy)

2017-11-15

The aim of this study was to evaluate the role of imaging features derived from [{sup 18}F]FDG-PET/CT to provide in vivo characterization of breast cancer (BC). Images from 43 patients with a first diagnosis of BC were reviewed. Images were acquired before any treatment. Histological data were derived from pretreatment biopsy or surgical histological specimen; these included tumor type, grade, ER and PgR receptor status, lymphovascular invasion, Ki67 index, HER2 status, and molecular subtype. Standard parameters (SUV{sub mean}, TLG, MTV) and advanced imaging features (histogram-based and shape and size features) were evaluated. Univariate analysis, hierarchical clustering analysis, and exact Fisher's test were used for statistical analysis of data. Imaging-derived metrics were reduced evaluating the mutual correlation within group of features as well as the mutual correlation between groups of features to form a signature. A significant correlation was found between some advanced imaging features and the histological type. Different molecular subtypes were characterized by different values of two histogram-based features (median and energy). A significant association was observed between the imaging signature and luminal A and luminal B HER2 negative molecular subtype and also when considering luminal A, luminal B HER2-negative and HER2-positive groups. Similar results were found between the signature and all five molecular subtypes and also when considering the histological types of BC. Our results suggest a complementary role of standard PET imaging parameters and advanced imaging features for the in vivo biological characterization of BC lesions. (orig.)

CSF Venous Fistulas in Spontaneous Intracranial Hypotension: Imaging Characteristics on Dynamic and CT Myelography.

Science.gov (United States)

Kranz, Peter G; Amrhein, Timothy J; Gray, Linda

2017-12-01

The objective of this study is to describe the anatomic and imaging features of CSF venous fistulas, which are a recently reported cause of spontaneous intracranial hypotension (SIH). We retrospectively reviewed the records of patients with SIH caused by CSF venous fistulas who received treatment at our institution. The anatomic details of each fistula were recorded. Attenuation of the veins involved by the fistula was compared with that of adjacent control veins on CT myelography (CTM). Visibility of the CSF venous fistula on CTM and a modified conventional myelography technique we refer to as dynamic myelography was also compared. Twenty-two cases of CSF venous fistula were identified. The fistulas were located between T4 and L1. Ninety percent occurred without a concurrent epidural CSF leak. In most cases (82%), the CSF venous fistula originated from a nerve root sleeve diverticulum. On CTM, the abnormal veins associated with the CSF venous fistula were seen in a paravertebral location in 45% of cases, centrally within the epidural venous plexus in 32%, and lateral to the spine in 23%. Differences in attenuation between the fistula veins and the control veins was highly statistically significant (p CSF venous fistulas are an important cause of SIH that can be detected on both CTM and dynamic myelograph y and may occur without an epidural CSF leak. Familiarity with the imaging characteristics of these lesions is critical to providing appropriate treatment to patients with SIH.

Technological features and clinical feasibility of megavoltage CT scanning

International Nuclear Information System (INIS)

Nakagawa, Keiichi; Aoki, Yukimasa; Akanuma, Atsuo; Sakata, Kouichi; Karasawa, Katsuyuki; Terahara, Atsurou; Onogi, Yuzou; Hasezawa, Kenji; Sasaki, Yasuhito

1992-01-01

Megavoltage CT scanning using 4-MV and 6-MV radiotherapy beams has been developed and applied to verify errors in patient positioning. A detector system composed of 120 pairs of cadmium tungstate scintillators with photodiodes is mounted to the treatment unit at a distance of 160 cm from the beam source. Image reconstruction is performed with a standard filtered back-projection algorithm. Scanning time and reconstruction time for a slice is approximately 35 s and 60 s respectively. Although spatial resolution is as large as 4 mm, it has sufficient image quality to be applied for treatment planning and verification. The delivered dose with 4 MV and 6 MV is about 1.4 cGy and 2.8 cGy respectively. When a megavoltage CT image is taken in treatment position, the positioning errors are easily detected by comparing it with diagnostic CT sections for treatment planning. Several clinical examples are presented. (orig.)

CT of the neonatal head

International Nuclear Information System (INIS)

Mohan, S.; Rogan, E.A.; Batty, R.; Raghavan, A.; Whitby, E.H.; Hart, A.R.; Connolly, D.J.A.

2013-01-01

Computed tomography (CT) is used less often than other techniques on neonatal units. However, in the acute setting, CT can be invaluable in diagnosing or excluding potentially life-threatening conditions and guiding initial management in neonates. Common indications for scanning include trauma, suspected non-accidental injury, infection, or an acute hypoxic or metabolic event. The aim of this review is to provide an overview of the normal neonatal head at CT and compare this to the common pathological abnormalities. Several key features of each condition will be highlighted. It is important to note that some pathological conditions can have overlapping features at CT and, therefore, the clinical history and additional investigations are also of key importance in determining the diagnosis

Microsoft Dynamics CRM 2011 New Features The Real-world Tutorial

CERN Document Server

Wang, Jim

2011-01-01

This book is packed with practical steps and screenshots to make learning fun and addictive. You will learn to build a complete Airline Compensation Management system using Dynamics CRM 2011. If you want a focused book that gets you up-to-speed with the new features of Microsft Dynamics CRM 2011 then this is the perfect book for you.

Dynamic binding of visual features by neuronal/stimulus synchrony.

Science.gov (United States)

Iwabuchi, A

1998-05-01

When people see a visual scene, certain parts of the visual scene are treated as belonging together and we regard them as a perceptual unit, which is called a "figure". People focus on figures, and the remaining parts of the scene are disregarded as "ground". In Gestalt psychology this process is called "figure-ground segregation". According to current perceptual psychology, a figure is formed by binding various visual features in a scene, and developments in neuroscience have revealed that there are many feature-encoding neurons, which respond to such features specifically. It is not known, however, how the brain binds different features of an object into a coherent visual object representation. Recently, the theory of binding by neuronal synchrony, which argues that feature binding is dynamically mediated by neuronal synchrony of feature-encoding neurons, has been proposed. This review article portrays the problem of figure-ground segregation and features binding, summarizes neurophysiological and psychophysical experiments and theory relevant to feature binding by neuronal/stimulus synchrony, and suggests possible directions for future research on this topic.

Linguistic labels, dynamic visual features, and attention in infant category learning.

Science.gov (United States)

Deng, Wei Sophia; Sloutsky, Vladimir M

2015-06-01

How do words affect categorization? According to some accounts, even early in development words are category markers and are different from other features. According to other accounts, early in development words are part of the input and are akin to other features. The current study addressed this issue by examining the role of words and dynamic visual features in category learning in 8- to 12-month-old infants. Infants were familiarized with exemplars from one category in a label-defined or motion-defined condition and then tested with prototypes from the studied category and from a novel contrast category. Eye-tracking results indicated that infants exhibited better category learning in the motion-defined condition than in the label-defined condition, and their attention was more distributed among different features when there was a dynamic visual feature compared with the label-defined condition. These results provide little evidence for the idea that linguistic labels are category markers that facilitate category learning. Copyright © 2015 Elsevier Inc. All rights reserved.

Value of early follow-up CT in paediatric tuberculous meningitis

International Nuclear Information System (INIS)

Andronikou, Savvas; Wieselthaler, Nicky; Smith, Bruce; Douis, Hassan; Fieggen, A. Graham; Toorn, Ronald van; Wilmshurst, Jo

2005-01-01

The value of CT in the diagnosis of tuberculous meningitis (TBM) in children is well reported. Follow-up CT scanning for these patients is, however, not well described and, in particular, the value of early follow-up CT has not been addressed for children with TBM. To assess the value of early follow-up CT in children with TBM in identifying diagnostic, prognostic and therapeutically relevant features of TBM. A retrospective 4-year review of CT scans performed within 1 week and 1 month of initial CT in children with proven (CSF culture-positive) and probable TBM (CSF profile-positive but culture-negative) and comparison with initial CT for the diagnostic, prognostic and therapeutic CT features of TBM. The CT scans of 50 children were included (19 ''definite'' TBM; 31 ''probable'' TBM). Of these, 30 had CT scans performed within 1 week of the initial CT. On initial CT, 44 patients had basal enhancement. Only 24 patients had contrast medium-enhanced follow-up scans. Important findings include: 8 of 29 patients (who were not shunted) developed new hydrocephalus. New infarcts developed in 24 patients; 45% of those who did not have infarction initially developed new infarcts. Three of the six patients who did not show basal enhancement on initial scans developed this on the follow-up scans, while in seven patients with pre-existing basal enhancement this became more pronounced. Two patients developed hyperdensity in the cisterns on non-contrast medium scans. Eight patients developed a diagnostic triad of features. Three patients developed CT features of TBM where there was none on the initial scans. Early follow-up CT is useful in making a diagnosis of TBM by demonstrating features that were not present initially and by demonstrating more sensitive, obvious or additional features of TBM. In addition, follow-up CT is valuable as a prognostic indicator as it demonstrates additional infarcts which may have developed or become more visible since the initial study. Lastly

Value of early follow-up CT in paediatric tuberculous meningitis

Energy Technology Data Exchange (ETDEWEB)

Andronikou, Savvas [University of Cape Town, Department of Radiology, Cape Town (South Africa); Wieselthaler, Nicky; Smith, Bruce; Douis, Hassan [Red Cross Children' s Hospital, Department of Paediatric Radiology, School of Child and Adolescent Health, Cape Town (South Africa); Fieggen, A. Graham; Toorn, Ronald van; Wilmshurst, Jo [Red Cross Children' s Hospital, Department of Paediatric Radiology, School of Child and Adolescent Health, Cape Town (South Africa); Red Cross Children' s Hospital, Department of Neurosciences, School of Child and Adolescent Health, Cape Town (South Africa)

2005-11-01

The value of CT in the diagnosis of tuberculous meningitis (TBM) in children is well reported. Follow-up CT scanning for these patients is, however, not well described and, in particular, the value of early follow-up CT has not been addressed for children with TBM. To assess the value of early follow-up CT in children with TBM in identifying diagnostic, prognostic and therapeutically relevant features of TBM. A retrospective 4-year review of CT scans performed within 1 week and 1 month of initial CT in children with proven (CSF culture-positive) and probable TBM (CSF profile-positive but culture-negative) and comparison with initial CT for the diagnostic, prognostic and therapeutic CT features of TBM. The CT scans of 50 children were included (19 ''definite'' TBM; 31 ''probable'' TBM). Of these, 30 had CT scans performed within 1 week of the initial CT. On initial CT, 44 patients had basal enhancement. Only 24 patients had contrast medium-enhanced follow-up scans. Important findings include: 8 of 29 patients (who were not shunted) developed new hydrocephalus. New infarcts developed in 24 patients; 45% of those who did not have infarction initially developed new infarcts. Three of the six patients who did not show basal enhancement on initial scans developed this on the follow-up scans, while in seven patients with pre-existing basal enhancement this became more pronounced. Two patients developed hyperdensity in the cisterns on non-contrast medium scans. Eight patients developed a diagnostic triad of features. Three patients developed CT features of TBM where there was none on the initial scans. Early follow-up CT is useful in making a diagnosis of TBM by demonstrating features that were not present initially and by demonstrating more sensitive, obvious or additional features of TBM. In addition, follow-up CT is valuable as a prognostic indicator as it demonstrates additional infarcts which may have developed or become more

Clinical and CT features of benign pneumatosis intestinalis in pediatric hematopoietic stem cell transplant and oncology patients

International Nuclear Information System (INIS)

McCarville, M.B.; Goodin, Geoffrey S.; Whittle, Sarah B.; Li, Chin-Shang; Smeltzer, Matthew P.; Hale, Gregory A.; Kaufman, Robert A.

2008-01-01

Pneumatosis intestinalis in children is associated with a wide variety of underlying conditions and often has a benign course. The CT features of this condition have not been systematically investigated. Defining benign pneumatosis intestinalis as pneumatosis intestinalis that resolved with medical management alone, we sought to: (1) determine whether the incidence of benign pneumatosis intestinalis had increased at our pediatric cancer hospital; (2) characterize CT features of benign pneumatosis intestinalis; and (3) determine the relationship between imaging features and clinical course of benign pneumatosis intestinalis in this cohort. Radiology reports from November 1994 to December 2006 were searched for ''pneumatosis intestinalis,'' ''free intraperitoneal air,'' and ''portal venous air or gas.'' Corresponding imaging was reviewed by two radiologists who confirmed pneumatosis intestinalis and recorded the presence of extraluminal free air, degree of intramural gaseous distension, number of involved bowel segments, and time to pneumatosis resolution. The search revealed 12 boys and 4 girls with pneumatosis intestinalis; 11 were hematopoietic stem cell transplant recipients. The annual incidences of benign pneumatosis have not changed at our institution. Increases in intramural distension marginally correlated with the number of bowel segments involved (P=0.08). Three patients had free air and longer times to resolution of pneumatosis (P=0.03). Male children may be at increased risk of benign pneumatosis intestinalis. The incidence of benign pneumatosis at our institution is proportional to the number of hematopoietic stem cell transplants. The degree of intramural distension may correlate with the number of bowel segments involved. Patients with free air have a longer time to resolution of benign pneumatosis. (orig.)

Automatic extraction of forward stroke volume using dynamic 11C-acetate PET/CT

DEFF Research Database (Denmark)

Harms, Hans; Tolbod, Lars Poulsen; Hansson, Nils Henrik

Objectives: Dynamic PET with 11C-acetate can be used to quantify myocardial blood flow and oxidative metabolism, the latter of which is used to calculate myocardial external efficiency (MEE). Calculation of MEE requires forward stroke volume (FSV) data. FSV is affected by cardiac loading conditions......, potentially introducing bias if measured with a separate modality. The aim of this study was to develop and validate methods for automatically extracting FSV directly from the dynamic PET used for measuring oxidative metabolism. Methods: 16 subjects underwent a dynamic 27 min PET scan on a Siemens Biograph...... TruePoint 64 PET/CT scanner after bolus injection of 399±27 MBq of 11C-acetate. The LV-aortic time-activity curve (TAC) was extracted automatically from dynamic PET data using cluster analysis. The first-pass peak was derived by automatic extrapolation of the down-slope of the TAC. FSV...

Information Processing Features Can Detect Behavioral Regimes of Dynamical Systems

Directory of Open Access Journals (Sweden)

Rick Quax

2018-01-01

Full Text Available In dynamical systems, local interactions between dynamical units generate correlations which are stored and transmitted throughout the system, generating the macroscopic behavior. However a framework to quantify exactly how these correlations are stored, transmitted, and combined at the microscopic scale is missing. Here we propose to characterize the notion of “information processing” based on all possible Shannon mutual information quantities between a future state and all possible sets of initial states. We apply it to the 256 elementary cellular automata (ECA, which are the simplest possible dynamical systems exhibiting behaviors ranging from simple to complex. Our main finding is that only a few information features are needed for full predictability of the systemic behavior and that the “information synergy” feature is always most predictive. Finally we apply the idea to foreign exchange (FX and interest-rate swap (IRS time-series data. We find an effective “slowing down” leading indicator in all three markets for the 2008 financial crisis when applied to the information features, as opposed to using the data itself directly. Our work suggests that the proposed characterization of the local information processing of units may be a promising direction for predicting emergent systemic behaviors.

Diagnostic value of transmural perfusion ratio derived from dynamic CT-based myocardial perfusion imaging for the detection of haemodynamically relevant coronary artery stenosis

Energy Technology Data Exchange (ETDEWEB)

Coenen, Adriaan; Lubbers, Marisa M.; Dedic, Admir; Chelu, Raluca G.; Geuns, Robert-Jan M. van; Nieman, Koen [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Erasmus University Medical Center, Department of Cardiology, Rotterdam (Netherlands); Kurata, Akira; Kono, Atsushi; Dijkshoorn, Marcel L. [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Rossi, Alexia [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Barts Health NHS Trust, NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London and Department of Cardiology, London (United Kingdom)

2017-06-15

To investigate the additional value of transmural perfusion ratio (TPR) in dynamic CT myocardial perfusion imaging for detection of haemodynamically significant coronary artery disease compared with fractional flow reserve (FFR). Subjects with suspected or known coronary artery disease were prospectively included and underwent a CT-MPI examination. From the CT-MPI time-point data absolute myocardial blood flow (MBF) values were temporally resolved using a hybrid deconvolution model. An absolute MBF value was measured in the suspected perfusion defect. TPR was defined as the ratio between the subendocardial and subepicardial MBF. TPR and MBF results were compared with invasive FFR using a threshold of 0.80. Forty-three patients and 94 territories were analysed. The area under the receiver operator curve was larger for MBF (0.78) compared with TPR (0.65, P = 0.026). No significant differences were found in diagnostic classification between MBF and TPR with a territory-based accuracy of 77 % (67-86 %) for MBF compared with 70 % (60-81 %) for TPR. Combined MBF and TPR classification did not improve the diagnostic classification. Dynamic CT-MPI-based transmural perfusion ratio predicts haemodynamically significant coronary artery disease. However, diagnostic performance of dynamic CT-MPI-derived TPR is inferior to quantified MBF and has limited incremental value. (orig.)

Characteristic features of computed tomography (CT) in hepatic schistosomiasis japonica

Energy Technology Data Exchange (ETDEWEB)

Sakemi, Taisuke; Sakai, Terufumi; Majima, Yasuo [Kurume Univ., Fukuoka (Japan). School of Medicine

1984-06-01

Characteristic finding of CT in the liver of hepatic schistosomiasis japonica were compared with histological changes. The study was made on 7 cases with schistosomatic liver cirrhosis (SLC) and 7 SLC cases with hepatocellular carcinoma (HCC). Characteristic CT findings were high density funicular patterns showing turtle shell appearance (4 cases), high density spotty patterns (3 cases) and both mixed patterns (7 cases). These patterns were not changed by contrast medium study. Funicular and mixed patterns were observed in both lobes of the liver, however, spotty patterns were seen only in the right lobe. It was difficult to distinguish liver tissue surrounded by funicular patterns from HCC lesion. Histopathological study of autopsied livers and CT scanning of thin cut livers revealed that high density funicular patterns represent deposits of calcified schistosomal ova in the fibrous septa.

A prospective analysis of {sup 18}F-FDG PET/CT in patients with uveal melanoma: comparison between metabolic rate of glucose (MRglu) and standardized uptake value (SUV) and correlations with histopathological features

Energy Technology Data Exchange (ETDEWEB)

Calcagni, Maria Lucia; Mattoli, Maria Vittoria; Rufini, Vittoria; Giordano, Alessandro [Universita Cattolica del Sacro Cuore, Institute of Nuclear Medicine, Roma (Italy); Blasi, Maria Antonietta; Sammarco, Maria Grazia [Universita Cattolica del Sacro Cuore, Institute of Ophthalmology, Roma (Italy); Petrone, Gianluigi; Mule, Antonino [Universita Cattolica del Sacro Cuore, Department of Pathology, Roma (Italy); Indovina, Luca [Universita Cattolica del Sacro Cuore, Physics Unit, Roma (Italy)

2013-10-15

To evaluate whether standardized uptake value (SUV) and/or metabolic rate of glucose (MRglu) are different among epithelioid, mixed, and spindle cell uveal melanomas, as well as between low and high risk melanomas; to correlate ultrasonographic data and metabolic parameters with histopathological features; and to assess the role of {sup 18}F-FDG PET/CT for evaluating prognosis. Of 34 eligible patients prospectively enrolled with clinical suspicion of medium/large uveal melanoma, 26 (15 men, mean age 62.8 {+-} 11.8 years) were evaluated. All patients underwent metastatic work-up, 3-D dynamic brain and whole-body {sup 18}F-FDG PET/CT, and surgery. Of the 26 ocular lesions, 23 showed {sup 18}F-FDG uptake, with a sensitivity of 88 %. MRglu was significantly higher in the epithelioid cell melanomas than in the spindle cell melanomas, as well as in high-risk lesions than in low-risk lesions (p = 0.01, p = 0.02, respectively). SUV and MRglu were correlated with histopathological features while ultrasonographic data were not. MRglu is useful for distinguishing the different cell types in uveal melanoma, as well as high-risk from low-risk lesions, while SUV is not. MRglu provides a more accurate evaluation of glucose consumption, whereas SUV provides only an estimation. In addition, the metabolic parameters correlate with histopathological features, well also reflecting cellular behaviour in ocular malignancy. A longer follow-up is needed to assess the role of {sup 18}F-FDG in evaluating prognosis. (orig.)

The role of CT in diagnosing small hepatic tumors; Usefulness of table incremental dynamic CT (ICT)

Energy Technology Data Exchange (ETDEWEB)

Usuki, Noriaki; Daikokuya, Hideo; Fukuda, Haruyuki; Saiwai, Shigeo; Nakajima, Hideyuki; Miyamoto, Takeshi; Kudo, Masatoshi (Kobe General Hospital, Hyogo (Japan))

1992-11-01

Twenty-seven cases of small hepatic tumors were examined by MRI and CT (ICT). MRI was more sensitive than plain and contrast CT. But ICT could detect more small lesions than MRI. CT is not more superior modality than MRI untill ICT is performed. It is concluded ICT should be done when diagnosing small hepatic tumors by CT. (author).

CT Imaging Features in the Characterization of Non-Growing Solid Pulmonary Nodules in Non-Smokers

International Nuclear Information System (INIS)

Perandini, Simone; Soardi, Gian Alberto; Motton, Massimiliano; Augelli, Raffaele; Zantedeschi, Lisa; Montemezzi, Stefania

2016-01-01

A disappearing or persistent solid pulmonary nodule is a neglected clinical entity that still poses serious interpretative issues to date. Traditional knowledge deriving from previous reports suggests particular features, such as smooth edges or regular shape, to be significantly associated with benignity. A large number of benign nodules are reported among smokers in lung cancer screening programmes. The aim of this single-center retrospective study was to correlate specific imaging features to verify if traditional knowledge as well as more recent acquisitions regarding benign SPNs can be considered reliable in a current case series of nodules collected in a non-smoker cohort of patients. Fifty-three solid SPNs proven as non-growing during follow-up imaging were analyzed with regard to their imaging features at thin-section CT, their predicted malignancy risk according to three major risk assessment models, minimum density analysis and contrast enhanced-CT in the relative subgroups of nodules which underwent such tests. Eleven nodules disappeared during follow-up, 29 showed volume loss and 16 had a VDT of 1121 days or higher. There were 48 nodules located peripherally (85.71%). Evaluation of the enhancement after contrast media (n=29) showed mean enhancement ±SD of 25.72±35.03 HU, median of 18 HU, ranging from 0 to 190 HU. Minimum density assessment (n=30) showed mean minimum HU ±SD of −28.27±47.86 HU, median of −25 HU, ranging from −144 to 68 HU. Mean malignancy risk ±SD was 15.05±26.69% for the BIMC model, 17.22±19.00% for the Mayo Clinic model and 19.07±33.16% for the Gurney’s model. Our analysis suggests caution in using traditional knowledge when dealing with current small solid peripheral indeterminate SPNs and highlights how quantitative growth at follow-up should be the cornerstone of characterization

A Method for Extracting Suspected Parotid Lesions in CT Images using Feature-based Segmentation and Active Contours based on Stationary Wavelet Transform

Science.gov (United States)

Wu, T. Y.; Lin, S. F.

2013-10-01

Automatic suspected lesion extraction is an important application in computer-aided diagnosis (CAD). In this paper, we propose a method to automatically extract the suspected parotid regions for clinical evaluation in head and neck CT images. The suspected lesion tissues in low contrast tissue regions can be localized with feature-based segmentation (FBS) based on local texture features, and can be delineated with accuracy by modified active contour models (ACM). At first, stationary wavelet transform (SWT) is introduced. The derived wavelet coefficients are applied to derive the local features for FBS, and to generate enhanced energy maps for ACM computation. Geometric shape features (GSFs) are proposed to analyze each soft tissue region segmented by FBS; the regions with higher similarity GSFs with the lesions are extracted and the information is also applied as the initial conditions for fine delineation computation. Consequently, the suspected lesions can be automatically localized and accurately delineated for aiding clinical diagnosis. The performance of the proposed method is evaluated by comparing with the results outlined by clinical experts. The experiments on 20 pathological CT data sets show that the true-positive (TP) rate on recognizing parotid lesions is about 94%, and the dimension accuracy of delineation results can also approach over 93%.

Feature Extraction for Structural Dynamics Model Validation

Energy Technology Data Exchange (ETDEWEB)

Farrar, Charles [Los Alamos National Laboratory; Nishio, Mayuko [Yokohama University; Hemez, Francois [Los Alamos National Laboratory; Stull, Chris [Los Alamos National Laboratory; Park, Gyuhae [Chonnam Univesity; Cornwell, Phil [Rose-Hulman Institute of Technology; Figueiredo, Eloi [Universidade Lusófona; Luscher, D. J. [Los Alamos National Laboratory; Worden, Keith [University of Sheffield

2016-01-13

As structural dynamics becomes increasingly non-modal, stochastic and nonlinear, finite element model-updating technology must adopt the broader notions of model validation and uncertainty quantification. For example, particular re-sampling procedures must be implemented to propagate uncertainty through a forward calculation, and non-modal features must be defined to analyze nonlinear data sets. The latter topic is the focus of this report, but first, some more general comments regarding the concept of model validation will be discussed.

Imaging features of intraductal papillary neoplasm of the bile duct

International Nuclear Information System (INIS)

Liu Yubao; Li Meng; Zhong Xiaomei; Liu Zaiyi; Liang Changhong

2014-01-01

Objective: To investigate the CT and MRI features of intraductal papillary neoplasm of the bile duct (IPNB). Methods: Thirty eight patients with IPNB finally diagnosed by puncture biopsy or surgery were enrolled in this study. All the CT or MRI data were investigated retrospectively. Twenty one patients underwent CT examinations, 17 patients underwent MRI examinations. The features of IPNB including the distribution features of the nodules or masses, CT and MRI features of cholangiectasis, mucus were analyzed. The accuracy differences of CT and MRI for the preoperatively diagnosing mucus and tumor growing along mucous were compared by nonparametric test. Results: The lesions (including 5 patients with solitary lesions and 19 patients with multiple lesions) were located in intrahepatic bile duct in 24 patients, 3 patients occurred simultaneously in intrahepatic and portal bile duct, 2 lesions occurred in portal bile duct, 8 lesions occurred in common bile duct, the lesions of 1 patient occurred simultaneously in common bile duct, cystic duct and gallbladder. Seventeen and 11 patients appeared nodules locating in dilated bile duct on CT and MRI, respectively. Four and 5 patients appeared cystic lesions with multiple nodules of the liver on CT and MRI, respectively. Higher contrast enhancement on CT and MRI in arterial phase than that in portal vein and equilibrium phase were observed in 18 and 12 patients, respectively. Excluding the patients undergoing puncture, CT was better than MRI in evaluating whether the mucus was present, with the accuracies of 30.0% (6/20) and 6.3% (1/16) for CT and MRI, respectively (Z=2.58, P<0.05). CT was worse than MRI in preoperatively evaluating the features of tumor growing along mucous, with the accuracies of 77.8% (14/18) and 92.6% (13/14) for CT and MRI, respectively (Z=4.23, P<0.01). Conclusion: IPNB had the features of growing along mucous of the bile duct, nodule or mass in dilated bile duct and other features, CT and MRI are

Association between CT-evaluated lumbar lordosis and features of spinal degeneration, evaluated in supine position

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Kalichman, Leonid; Li, Ling; Hunter, David; Been, Ella

2013-01-01

Background Context Few studies have directly evaluated the association of lumbar lordosis and segmental wedging of the vertebral bodies and intervertebral disks with prevalence of spinal degenerative features. Purpose To evaluate the association of CT-evaluated lumbar lordosis, segmental wedging of the vertebral bodies and that of the intervertebral disks with various spinal degeneration features. Study design This cross-sectional study was a nested project to the Framingham Heart Study. Sample A random consecutive subset of 191 participants chosen from the 3590 participants enrolled in the Framingham Heart Study who underwent multi-detector CT to assess aortic calcification. Outcome Measures Physiologic Measures Dichotomous variables indicating the presence of intervertebral disc narrowing, facet joint osteoarthritis, spondylolysis, spondylolisthesis and spinal stenosis and density (in Hounsfield units) of multifidus and erector spinae muscles were evaluated on supine CT, as well as the lordosis angle (LA) and the wedging of the vertebral bodies and intervertebral disks. Sum of vertebral bodies wedging (ΣB) and sum of intervertebral discs wedging (ΣD) were used in analyses. Methods Mean values (±SD) of LA, ΣB and ΣD were calculated in males and females and compared using the t-test. Mean values (±SD) of LA, ΣB and ΣD in 4 age groups: 0.05) with increasing age. LA showed statistically significant association with presence of spondylolysis (OR(95%CI): 1.08(1.02–1.14)) and with density of multifidus (1.06 (1.01–1.11). as well as a marginally significant association with isthmic spondylolisthesis (1.07(1.00–1.14). ΣB showed a positive association with degenerative spondylolisthesis and disc narrowing ((1.14(1.06–1.23) and 1.04 (1.00–1.08), correspondingly), whereas ΣD showed negative one (0.93(0.87–0.98) and (0.93(0.89–0.97), correspondingly). Conclusions Significant associations were found between lumbar lordosis evaluated in supine position

Comparison of 133Xe gas dynamic SPECT and thin-section CT in patients with pulmonary emphysema

International Nuclear Information System (INIS)

Takahashi, Kazue; Satoh, Katashi; Ohkawa, Motoomi

2001-01-01

We assessed 133 Xe gas dynamic single photon emission computed tomography (SPECT) by comparing washout axial images with thin-section CT (TSCT) in patients with pulmonary emphysema. Twenty-three patients were studied. All patients were diagnosed as having pulmonary emphysema on the basis of TSCT. We compared TSCT of upper, middle and lower lung fields with 133 Xe gas dynamic SPECT axial images at the corresponding levels during the 3 to 4 minutes of washout phase. If the degree of 133 Xe gas retention or TSCT finding of ventral and dorsal parts was not the same, the images were divided into two parts. A total of 174 lesions in 23 cases were examined, but 3 lesions having no retention of 133 Xe gas at equilibrium phase were excluded. The results showed that: there were 37 lesions (21.6%) with equivalent severity on both images; there were 42 lesions (24.5%) with more severity on 133 Xe gas dynamic SPECT than on TSCT; and there were 92 lesions (53.8%) with more severity on TSCT than on 133 Xe gas dynamic SPECT. The severity on 133 Xe gas dynamic SPECT and TSCT was not always compatible. One of the reasons for the variable 133 Xe gas retention even when the lesion had the same severity on TSCT, may be bronchial stricture which cannot be seen on TSCT. By comparison of axial images of 133 Xe gas dynamic SPECT with CT images, we could recognize the areas of 133 Xe gas retention in detail. Results suggest that 133 Xe gas dynamic SPECT can be useful to identify ventilation impairment in pulmonary emphysema. (author)

Dynamic multidetector CT and non-contrast-enhanced MR for right adrenal vein imaging: comparison with catheter venography in adrenal venous sampling

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Ota, Hideki; Seiji, Kazumasa; Kawabata, Masahiro; Satani, Nozomi; Matsuura, Tomonori; Tominaga, Junya; Takase, Kei [Tohoku University Hospital, Department of Diagnostic Radiology, Sendai (Japan); Omata, Kei; Ono, Yoshikiyo; Iwakura, Yoshitsugu; Morimoto, Ryo; Kudo, Masataka; Satoh, Fumitoshi; Ito, Sadayoshi [Tohoku University Hospital, Division of Nephrology, Endocrinology and Vascular Medicine, Sendai (Japan)

2016-03-15

To evaluate visualization of the right adrenal vein (RAV) with multidetector CT and non-contrast-enhanced MR imaging in patients with primary aldosteronism. A total of 125 patients (67 men) scheduled for adrenal venous sampling (AVS) were included. Dynamic 64-detector-row CT and balanced steady-state free precession-based non-contrast-enhanced 3-T MR imaging were performed. RAV visualization based on a four-point score was documented. Both anatomical location and variation on cross-sectional imaging were evaluated, and the findings were compared with catheter venography as the gold standard. The RAV was visualized in 93.2 % by CT and 84.8 % by MR imaging (p = 0.02). Positive predictive values of RAV visualization were 100 % for CT and 95.2 % for MR imaging. Imaging score was significantly higher in CT than MR imaging (p < 0.01). The RAV formed a common trunk with an accessory hepatic vein in 16 % of patients. The RAV orifice level on cross-sectional imaging was concordant with catheter venography within the range of 1/3 vertebral height in >70 % of subjects. Success rate of AVS was 99.2 %. Dynamic CT is a reliable way to map the RAV prior to AVS. Non-contrast-enhanced MR imaging is an alternative when there is a risk of complication from contrast media or radiation exposure. (orig.)

18F-Fluorodeoxyglucose PET/CT and dynamic contrast-enhanced MRI as imaging biomarkers in malignant pleural mesothelioma.

Science.gov (United States)

Hall, David O; Hooper, Clare E; Searle, Julie; Darby, Michael; White, Paul; Harvey, John E; Braybrooke, Jeremy P; Maskell, Nick A; Masani, Vidan; Lyburn, Iain D

2018-02-01

The purpose of this study was to compare the use of fluorine-18-fluorodeoxyglucose (F-FDG) PET with computed tomography (CT) and dynamic contrast-enhanced (DCE) MRI to predict prognosis and monitor treatment in malignant pleural mesothelioma. F-FDG PET/CT and DCE-MRI studies carried out as part of the South West Area Mesothelioma Pemetrexed trial were used. F-FDG PET/CT and DCE-MRI studies were carried out before treatment, and after two cycles of chemotherapy, on patients treated with pemetrexed and cisplatin. A total of 73 patients were recruited, of whom 65 had PET/CT and DCE-MRI scans. Baseline measurements from F-FDG PET/CT (maximum standardized uptake value, metabolic tumour volume and total lesion glycolysis) and DCE-MRI (integrated area under the first 90s of the curve and washout slope) were compared with overall survival (OS) using Kaplan-Meier and Cox regression analyses, and changes in imaging measurements were compared with disease progression. PET/CT and DCE-MRI measurements were not correlated with each other. Maximum standardized uptake value, metabolic tumour volume and total lesion glycolysis were significantly related to OS with Cox regression analysis and Kaplan-Meir analysis, and DCE-MRI washout curve shape was significantly related to OS. DCE-MRI curve shape can be combined with F-FDG PET/CT to give additional prognostic information. Changes in measurements were not related to progression-free survival. F-FDG PET/CT and DCE-MRI give prognostic information in malignant pleural mesothelioma. Neither PET/CT nor DCE-MRI is useful for monitoring disease progression.

High speed imaging of dynamic processes with a switched source x-ray CT system

International Nuclear Information System (INIS)

Thompson, William M; Lionheart, William R B; Morton, Edward J; Cunningham, Mike; Luggar, Russell D

2015-01-01

Conventional x-ray computed tomography (CT) scanners are limited in their scanning speed by the mechanical constraints of their rotating gantries and as such do not provide the necessary temporal resolution for imaging of fast-moving dynamic processes, such as moving fluid flows. The Real Time Tomography (RTT) system is a family of fast cone beam CT scanners which instead use multiple fixed discrete sources and complete rings of detectors in an offset geometry. We demonstrate the potential of this system for use in the imaging of such high speed dynamic processes and give results using simulated and real experimental data. The unusual scanning geometry results in some challenges in image reconstruction, which are overcome using algebraic iterative reconstruction techniques and explicit regularisation. Through the use of a simple temporal regularisation term and by optimising the source firing pattern, we show that temporal resolution of the system may be increased at the expense of spatial resolution, which may be advantageous in some situations. Results are given showing temporal resolution of approximately 500 µs with simulated data and 3 ms with real experimental data. (paper)

Enhancing pattern of gastric carcinoma at dynamic incremental CT: correlation with gross and histologic findings

International Nuclear Information System (INIS)

Shin, Hong Seop; Lee, Dong Ho; Kim, Yoon Hwa; Ko, Young Tae; Lim, Joo Won; Yoon, Yup

1996-01-01

To evaluate the enhancing pattern of gastric carcinomas at dynamic incremental CT and to correlate it with pathologic findings. We retrospectively evaluated the enhancement pattern of stomach cancer on dynamic incremental CT of the 78 patients. All the lesions had been pathologically proved after surgery. The enhancement pattern was categorized as good or poor in the early phase;homogeneous, heterogeneous or ring enhancement;the presence or absence of delayed enhancement. There were 16 cases of early gastric cancer (EGC), and 62 cases of advanced gastric cancer(AGC). The Borrmann type of AGC were 1(n=1), 2(n=20), 3=(n=32), 4(n=8) and 5(n=1). The histologic patterns of AGC were tubular(n=49), signet ring cell(n=10), and mucinous(n=3). The enhancing patterns were compared with gross and histologic findings and delayed enhancement was correlated with pathologic evidence of desmoplasia. Good enhancement of tumor was seen in 24/41cases (58.5%) with AGC Borrmann type 3-5, in 6/21(28.6%) with AGC Borrmann type 1-2, and in 3/16(18.8%) with EGC (P<.05). By histologic pattern, good enhancement of tumor was seen in 8/10(80%) with signet ring cell type, in 21/49(42.9%) with tubular type, and in 1/3(33.3%) with mucinous type(P<.05). EGC was homogeneously enhanced in 14/16cases (87.5%), but AGC was heterogeneously enhanced in 33/62(53.2%), respectively(P<.01). There was no significant correlation between delayed enhancement and the presence of desmoplasia. AGC Borrmann type 3-5 and signet ring cell type have a tendency to show good enhancement and EGC is more homogeneously enhanced at dynamic incremental CT

Selected PET radiomic features remain the same.

Science.gov (United States)

Tsujikawa, Tetsuya; Tsuyoshi, Hideaki; Kanno, Masafumi; Yamada, Shizuka; Kobayashi, Masato; Narita, Norihiko; Kimura, Hirohiko; Fujieda, Shigeharu; Yoshida, Yoshio; Okazawa, Hidehiko

2018-04-17

We investigated whether PET radiomic features are affected by differences in the scanner, scan protocol, and lesion location using 18 F-FDG PET/CT and PET/MR scans. SUV, TMR, skewness, kurtosis, entropy, and homogeneity strongly correlated between PET/CT and PET/MR images. SUVs were significantly higher on PET/MR 0-2 min and PET/MR 0-10 min than on PET/CT in gynecological cancer ( p = 0.008 and 0.008, respectively), whereas no significant difference was observed between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images in oral cavity/oropharyngeal cancer. TMRs on PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min increased in this order in gynecological cancer and oral cavity/oropharyngeal cancer. In contrast to conventional and histogram indices, 4 textural features (entropy, homogeneity, SRE, and LRE) were not significantly different between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images. 18 F-FDG PET radiomic features strongly correlated between PET/CT and PET/MR images. Dixon-based attenuation correction on PET/MR images underestimated tumor tracer uptake more significantly in oral cavity/oropharyngeal cancer than in gynecological cancer. 18 F-FDG PET textural features were affected less by differences in the scanner and scan protocol than conventional and histogram features, possibly due to the resampling process using a medium bin width. Eight patients with gynecological cancer and 7 with oral cavity/oropharyngeal cancer underwent a whole-body 18 F-FDG PET/CT scan and regional PET/MR scan in one day. PET/MR scans were performed for 10 minutes in the list mode, and PET/CT and 0-2 min and 0-10 min PET/MR images were reconstructed. The standardized uptake value (SUV), tumor-to-muscle SUV ratio (TMR), skewness, kurtosis, entropy, homogeneity, short-run emphasis (SRE), and long-run emphasis (LRE) were compared between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images.

Whole-brain dynamic CT angiography and perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

Orrison, W.W. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Department of Medical Education, University of Nevada School of Medicine, Reno, NV (United States); Snyder, K.V.; Hopkins, L.N. [Department of Neurosurgery, Millard Fillmore Gates Circle Hospital, Buffalo, NY (United States); Roach, C.J. [School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Ringdahl, E.N. [Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV (United States); Nazir, R. [Shifa International Hospital, Islamabad (Pakistan); Hanson, E.H., E-mail: eric.hanson@amigenics.co [College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States)

2011-06-15

The availability of whole brain computed tomography (CT) perfusion has expanded the opportunities for analysing the haemodynamic parameters associated with varied neurological conditions. Examples demonstrating the clinical utility of whole-brain CT perfusion imaging in selected acute and chronic ischaemic arterial neurovascular conditions are presented. Whole-brain CT perfusion enables the detection and focused haemodynamic analyses of acute and chronic arterial conditions in the central nervous system without the limitation of partial anatomical coverage of the brain.