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Sample records for tissues ct evaluation

  1. Evaluation of early tissue reactions after lumbar intertransverse process fusion using CT in a rabbit

    International Nuclear Information System (INIS)

    Shinbo, Jun; Mainil-Varlet, Pierre; Watanabe, Atsuya; Pippig, Suzanne; Koener, Jens; Anderson, Suzanne E.

    2010-01-01

    The objective of the study was to evaluate tissue reactions such as bone genesis, cartilage genesis and graft materials in the early phase of lumbar intertransverse process fusion in a rabbit model using computed tomography (CT) imaging with CT intensity (Hounsfield units) measurement, and to compare these data with histological results. Lumbar intertransverse process fusion was performed on 18 rabbits. Four graft materials were used: autograft bone (n=3); collagen membrane soaked with recombinant human bone morphogenetic protein-2 (rhBMP-2) (n=5); granular calcium phosphate (n=5); and granular calcium phosphate coated with rhBMP-2 (n=5). All rabbits were euthanized 3 weeks post-operatively and lumbar spines were removed for CT imaging and histological examination. Computed tomography imaging demonstrated that each fusion mass component had the appropriate CT intensity range. CT also showed the different distributions and intensities of bone genesis in the fusion masses between the groups. Each component of tissue reactions was identified successfully on CT images using the CT intensity difference. Using CT color mapping, these observations could be easily visualized, and the results correlated well with histological findings. The use of CT intensity is an effective approach for observing and comparing early tissue reactions such as newly synthesized bone, newly synthesized cartilage, and graft materials after lumbar intertransverse process fusion in a rabbit model. (orig.)

  2. PET-CT in the evaluation of sarcomas of soft tissues

    International Nuclear Information System (INIS)

    Serna M, J.A.; Quiroz C, O.; Sanchez C, N.; Diaz V, G.

    2007-01-01

    18 F-FDG PET-CT is an image modality of great utility in the evaluation of primary or recurrent lesions of soft tissues. It is necessary to determine the cost-benefit of the different image modalities, although one waits that by means of a better diagnostic, statification and the determination of the grade of malignancy, the PET-CT nowadays can reduce the cost and the complications of the invasive diagnostic methods. (Author)

  3. CT evaluation of soft tissue and muscle infection and inflammation: A systematic compartmental approach

    Energy Technology Data Exchange (ETDEWEB)

    Beauchamp, N.J. Jr. [Dept. of Radiology, and Radiological Science, The Johns Hopkins Medical Institutions, Baltimore, MD (United States); Scott, W.W. Jr. [Dept. of Radiology, and Radiological Science, The Johns Hopkins Medical Institutions, Baltimore, MD (United States); Gottlieb, L.M. [Dept. of Surgery, The Johns Hopkins Medical Institutions, Baltimore, MD (United States); Fishman, E.K. [Dept. of Surgery, The Johns Hopkins Medical Institutions, Baltimore, MD (United States)

    1995-07-01

    This essay presents a systematic approach to the evaluation of soft tissue and muscle infection by defining the various pathologic processes and then illustrating them through a series of CT studies with corresponding schematic diagrams. The specific processes discussed are cellulitis, lymphangitis/lymphedema, necrotizing fascitis, myositis/myonecrosis, and abscess. Key points in the differential diagnosis of these entities are discussed and illustrated. The clinical management of the specific pathologic processes is also discussed. (orig./MG)

  4. CT evaluation of soft tissue and muscle infection and inflammation: A systematic compartmental approach

    International Nuclear Information System (INIS)

    Beauchamp, N.J. Jr.; Scott, W.W. Jr.; Gottlieb, L.M.; Fishman, E.K.

    1995-01-01

    This essay presents a systematic approach to the evaluation of soft tissue and muscle infection by defining the various pathologic processes and then illustrating them through a series of CT studies with corresponding schematic diagrams. The specific processes discussed are cellulitis, lymphangitis/lymphedema, necrotizing fascitis, myositis/myonecrosis, and abscess. Key points in the differential diagnosis of these entities are discussed and illustrated. The clinical management of the specific pathologic processes is also discussed. (orig./MG)

  5. Synchrotron X-ray CT of rose peduncles. Evaluation of tissue damage by radiation

    International Nuclear Information System (INIS)

    Herppich, Werner B.; Zabler, Simon; Dawson, Martin; Choinka, Gerard; Manke, Ingo

    2015-01-01

    ''Bent-neck'' syndrome, an important postharvest problem of cut roses, is probably caused by water supply limitations and/or the structural weakness of vascular bundles of the peduncle tissue. For this reason, advanced knowledge about the microstructures of rose peduncles and their cultivar specific variations may lead to a better understanding of the underlying mechanisms. Synchrotron X-ray computed tomography (SXCT), especially phase-based CT, is a highly suitable technique to nondestructively investigate plants' micro anatomy. SXCT with monochromatic X-ray beams of 30, 40 and 50 keV photon energy was used to evaluate the three-dimensional inner structures of the peduncles of 3 rose cultivars that differ greatly in their bent-neck susceptibility. Results indicated that this technique achieves sufficiently high spatial resolution to investigate complex tissues. However, further investigations with chlorophyll fluorescence analysis (CFA) and optical microscope imagery reveal different kinds of heavy damage of the irradiated regions induced by synchrotron X-rays; in a cultivar-specific manner, partial destruction of cell walls occurred a few hours after X-ray irradiation. Furthermore, a delayed inhibition of photosynthesis accompanied by the degradation of chlorophyll was obvious from CFA within hours and days after the end of CT measurements. Although SXCT is certainly well suited for three-dimensional anatomical analysis of rose peduncles, the applied technique is not nondestructive.

  6. Synchrotron X-ray CT of rose peduncles. Evaluation of tissue damage by radiation

    Energy Technology Data Exchange (ETDEWEB)

    Herppich, Werner B. [Leibniz-Institut fuer Agrartechnik Potsdam-Bornim e.V., Potsdam (Germany). Abt. Technik im Gartenbau; Matsushima, Uzuki [Iwate Univ., Morioka (Japan). Faculty of Agriculture; Graf, Wolfgang [Association for Technology and Structures in Agriculture (KTBL), Darmstadt (Germany); Zabler, Simon [Fraunhofer-Institut fuer Integrierte Schaltungen (IIS), Wuerzburg (Germany). Project group NanoCT Systems (NCTS); Dawson, Martin [Salford Univ., Greater Manchester (United Kingdom); Choinka, Gerard; Manke, Ingo [Helmholtz Center Berlin for Materials and Energy (HZB), Berlin (Germany)

    2015-02-01

    ''Bent-neck'' syndrome, an important postharvest problem of cut roses, is probably caused by water supply limitations and/or the structural weakness of vascular bundles of the peduncle tissue. For this reason, advanced knowledge about the microstructures of rose peduncles and their cultivar specific variations may lead to a better understanding of the underlying mechanisms. Synchrotron X-ray computed tomography (SXCT), especially phase-based CT, is a highly suitable technique to nondestructively investigate plants' micro anatomy. SXCT with monochromatic X-ray beams of 30, 40 and 50 keV photon energy was used to evaluate the three-dimensional inner structures of the peduncles of 3 rose cultivars that differ greatly in their bent-neck susceptibility. Results indicated that this technique achieves sufficiently high spatial resolution to investigate complex tissues. However, further investigations with chlorophyll fluorescence analysis (CFA) and optical microscope imagery reveal different kinds of heavy damage of the irradiated regions induced by synchrotron X-rays; in a cultivar-specific manner, partial destruction of cell walls occurred a few hours after X-ray irradiation. Furthermore, a delayed inhibition of photosynthesis accompanied by the degradation of chlorophyll was obvious from CFA within hours and days after the end of CT measurements. Although SXCT is certainly well suited for three-dimensional anatomical analysis of rose peduncles, the applied technique is not nondestructive.

  7. PET-CT in the evaluation of sarcomas of soft tissues; PET-CT en la evaluacion de sarcomas de tejidos blandos

    Energy Technology Data Exchange (ETDEWEB)

    Serna M, J A; Quiroz C, O; Sanchez C, N; Diaz V, G [Hospital Angeles del Pedregal, Mexico D.F. (Mexico)

    2007-07-01

    {sup 18} F-FDG PET-CT is an image modality of great utility in the evaluation of primary or recurrent lesions of soft tissues. It is necessary to determine the cost-benefit of the different image modalities, although one waits that by means of a better diagnostic, statification and the determination of the grade of malignancy, the PET-CT nowadays can reduce the cost and the complications of the invasive diagnostic methods. (Author)

  8. Effects of extracorporeal shock wave lithotripsy on the kidney and perinephric tissues: CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Song, Kounn Sik; Kim, Kun Sang; Kim, Sae Chul [College of Medicine, Chung-Ang University, Seoul (Korea, Republic of)

    1987-12-15

    Since the first successful treatment of the patient with renal stone by extracorporeal shock wave lithotripsy at the Institute for Surgical Research, West Germany, on February 7, 1980, extracorporeal shock wave lithotripsy (ESWL) has been a non-invasive technique for the treatment of the renal and ureteral calculi. In spite of the fact that the acoustic energy of the focused shock waves must pass through the soft tissues of back, perinephric tissues and renal parenchyme before reaching calculi, little is known about the effects of ESWL in the renal parenchyme and perinephric soft tissues. So we analyzed a pre and post-ESWL computed tomography scans of the kidneys in 130 patients treated at our hospital during a three month period to evaluate the effects of ESWL on the kidney and perinephric soft tissues.

  9. Effects of extracorporeal shock wave lithotripsy on the kidney and perinephric tissues: CT evaluation

    International Nuclear Information System (INIS)

    Song, Kounn Sik; Kim, Kun Sang; Kim, Sae Chul

    1987-01-01

    Since the first successful treatment of the patient with renal stone by extracorporeal shock wave lithotripsy at the Institute for Surgical Research, West Germany, on February 7, 1980, extracorporeal shock wave lithotripsy (ESWL) has been a non-invasive technique for the treatment of the renal and ureteral calculi. In spite of the fact that the acoustic energy of the focused shock waves must pass through the soft tissues of back, perinephric tissues and renal parenchyme before reaching calculi, little is known about the effects of ESWL in the renal parenchyme and perinephric soft tissues. So we analyzed a pre and post-ESWL computed tomography scans of the kidneys in 130 patients treated at our hospital during a three month period to evaluate the effects of ESWL on the kidney and perinephric soft tissues

  10. Automated quantification of epicardial adipose tissue using CT angiography: evaluation of a prototype software

    International Nuclear Information System (INIS)

    Spearman, James V.; Silverman, Justin R.; Krazinski, Aleksander W.; Costello, Philip; Meinel, Felix G.; Geyer, Lucas L.; Schoepf, U.J.; Apfaltrer, Paul; Canstein, Christian; De Cecco, Carlo Nicola

    2014-01-01

    This study evaluated the performance of a novel automated software tool for epicardial fat volume (EFV) quantification compared to a standard manual technique at coronary CT angiography (cCTA). cCTA data sets of 70 patients (58.6 ± 12.9 years, 33 men) were retrospectively analysed using two different post-processing software applications. Observer 1 performed a manual single-plane pericardial border definition and EFV M segmentation (manual approach). Two observers used a software program with fully automated 3D pericardial border definition and EFV A calculation (automated approach). EFV and time required for measuring EFV (including software processing time and manual optimization time) for each method were recorded. Intraobserver and interobserver reliability was assessed on the prototype software measurements. T test, Spearman's rho, and Bland-Altman plots were used for statistical analysis. The final EFV A (with manual border optimization) was strongly correlated with the manual axial segmentation measurement (60.9 ± 33.2 mL vs. 65.8 ± 37.0 mL, rho = 0.970, P 0.9). Automated EFV A quantification is an accurate and time-saving method for quantification of EFV compared to established manual axial segmentation methods. (orig.)

  11. Automated quantification of epicardial adipose tissue using CT angiography: evaluation of a prototype software

    Energy Technology Data Exchange (ETDEWEB)

    Spearman, James V.; Silverman, Justin R.; Krazinski, Aleksander W.; Costello, Philip [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Meinel, Felix G.; Geyer, Lucas L. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Ludwig-Maximilians-University Hospital, Institute for Clinical Radiology, Munich (Germany); Schoepf, U.J. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Apfaltrer, Paul [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Institute of Clinical Radiology and Nuclear Medicine, Mannheim (Germany); Canstein, Christian [Siemens Medical Solutions USA, Inc., Malvern, PA (United States); De Cecco, Carlo Nicola [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' - Polo Pontino, Department of Radiological Sciences, Oncology and Pathology, Latina (Italy)

    2014-02-15

    This study evaluated the performance of a novel automated software tool for epicardial fat volume (EFV) quantification compared to a standard manual technique at coronary CT angiography (cCTA). cCTA data sets of 70 patients (58.6 ± 12.9 years, 33 men) were retrospectively analysed using two different post-processing software applications. Observer 1 performed a manual single-plane pericardial border definition and EFV{sub M} segmentation (manual approach). Two observers used a software program with fully automated 3D pericardial border definition and EFV{sub A} calculation (automated approach). EFV and time required for measuring EFV (including software processing time and manual optimization time) for each method were recorded. Intraobserver and interobserver reliability was assessed on the prototype software measurements. T test, Spearman's rho, and Bland-Altman plots were used for statistical analysis. The final EFV{sub A} (with manual border optimization) was strongly correlated with the manual axial segmentation measurement (60.9 ± 33.2 mL vs. 65.8 ± 37.0 mL, rho = 0.970, P < 0.001). A mean of 3.9 ± 1.9 manual border edits were performed to optimize the automated process. The software prototype required significantly less time to perform the measurements (135.6 ± 24.6 s vs. 314.3 ± 76.3 s, P < 0.001) and showed high reliability (ICC > 0.9). Automated EFV{sub A} quantification is an accurate and time-saving method for quantification of EFV compared to established manual axial segmentation methods. (orig.)

  12. Evaluation of Bone Metastasis from Hepatocellular Carcinoma Using 18F FDG PET/CT and 99mTc HDP Bone Scintigraphy: Characteristics of Soft Tissue Formation

    International Nuclear Information System (INIS)

    Seo, Hyo Jung; Choi, Yun Jung; Kim, Hyun Jeong; Jeong, Youg Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Choi, Hye Jin; Lee, Jong Doo; Kang, Won Jun

    2011-01-01

    Bone metastasis from hepatocellular carcinoma (HCC) can present with soft tissue formation, resulting in oncologic emergency. Contrast enhanced FDG PET/CT and bone scintigraphy were compared to evaluate characteristics of bone metastases with of without soft tissue formation from HCC. of 4,151 patients with HCC, 263 patients had bone metastases. Eighty five patients with bone metastasis from HCC underwent contrast enhanced FDG PET/CT. Fifty four of the enrolled subjects had recent 99mT c HDP bone scintigraphy available for comparison. Metastatic bone lesions were identified with visual inspection on FDG PET/CT, and maximum standardized uptake value (SUVmax) was used for the quantitative analysis. Confirmation of bone metastasis was based on histopathology, combined imaging modalities, or serial follow up studies. Forty seven patients (55%) presented with soft tissue formation, while the remaining 38 patients presented without soft tissue formation. Frequent sites of bone metastases from HCC were the spine (39%), pelvis (19%), and rib cage (14%). The soft tissue formation group had more frequent bone pain (77 vs. 37%, p<0.0001), higher SUVmax (6.02 vs. 3.52, p<0.007), and higher incidence of photon defect in bone scintigraphy (75 vs. 0%) compared to the non soft tissue formation group. FDG PET/CT had higher detection rate for bone metastasis than bone scintigraphy both in lesion based analysis (98 vs. 53%, p=0.0015) and in patient based analysis (100 vs. 80%, p<0.001). Bone metastasis from HCC showed a high incidence of soft tissue formation requiring emergency treatment. Although the characteristic findings for soft tissue formation such as photon defect in bone scintigraphy are helpful in detection, overall detectability of bone metastasis is higher in FDG PET/CT. Contrast enhanced PET/CT will be useful in finding and delineating soft tissue forming bone metastasis from HCC.

  13. Evaluation of the relationship between extremity soft tissue sarcomas and adjacent major vessels using contrast-enhanced multidetector CT and three-dimensional volume-rendered CT angiography - A preliminary study

    International Nuclear Information System (INIS)

    Li, YangKang; Lin, JianBang; Cai, AiQun; Zhou, XiuGuo; Zheng, Yu; Wei, XiaoLong; Cheng, Ying; Liu, GuoRui

    2013-01-01

    Background: Accurate description of the relationship between extremity soft tissue sarcoma and the adjacent major vessels is crucial for successful surgery. In addition to magnetic resonance imaging (MRI) or in patients who cannot undergo MRI, two-dimensional (2D) postcontrast computed tomography (CT) images and three-dimensional (3D) volume-rendered CT angiography may be valuable alternative imaging techniques for preoperative evaluation of extremity sarcomas. Purpose: To preoperatively assess extremity sarcomas using multidetector CT (MDCT), with emphasis on postcontrast MDCT images and 3D volume-rendered MDCT angiography in evaluating the relationship between tumors and adjacent major vessels. Material and Methods: MDCT examinations were performed on 13 patients with non-metastatic extremity sarcomas. Conventional CT images and 3D volume-rendered CT angiography were evaluated, with focus on the relationship between tumors and adjacent major vessels. Kappa consistency statistics were performed with surgery serving as the reference standard. Results: The relationship between sarcomas and adjacent vessels was described as one of three patterns: proximity, adhesion, and encasement. Proximity was seen in five cases on postcontrast CT images or in eight cases on volume-rendered images. Adhesion was seen in three cases on both postcontrast CT images and volume-rendered images. Encasement was seen in five cases on postcontrast CT images or in two cases on volume-rendered images. Compared to surgical results, postcontrast CT images had 100% sensitivity, 83.3% specificity, 87.5% positive predictive value, 100% negative predictive value, and 92.3% accuracy in the detection of vascular invasion (κ = 0.843, P = 0.002). 3D volume-rendered CT angiography had 71.4% sensitivity, 100% specificity, 100% positive predictive value, 75% negative predictive value, and 84.6% accuracy in the detection of vascular invasion (κ = 0.698, P = 0.008). On volume-rendered images, all cases

  14. Calibration and analysis of a multimodal micro-CT and structured light imaging system for the evaluation of excised breast tissue

    Science.gov (United States)

    McClatchy, David M., III; Rizzo, Elizabeth J.; Meganck, Jeff; Kempner, Josh; Vicory, Jared; Wells, Wendy A.; Paulsen, Keith D.; Pogue, Brian W.

    2017-12-01

    A multimodal micro-computed tomography (CT) and multi-spectral structured light imaging (SLI) system is introduced and systematically analyzed to test its feasibility to aid in margin delineation during breast conserving surgery (BCS). Phantom analysis of the micro-CT yielded a signal-to-noise ratio of 34, a contrast of 1.64, and a minimum detectable resolution of 240 μm for a 1.2 min scan. The SLI system, spanning wavelengths 490 nm to 800 nm and spatial frequencies up to 1.37 mm-1 , was evaluated with aqueous tissue simulating phantoms having variations in particle size distribution, scatter density, and blood volume fraction. The reduced scattering coefficient, μs\\prime and phase function parameter, γ, were accurately recovered over all wavelengths independent of blood volume fractions from 0% to 4%, assuming a flat sample geometry perpendicular to the imaging plane. The resolution of the optical system was tested with a step phantom, from which the modulation transfer function was calculated yielding a maximum resolution of 3.78 cycles per mm. The three dimensional spatial co-registration between the CT and optical imaging space was tested and shown to be accurate within 0.7 mm. A freshly resected breast specimen, with lobular carcinoma, fibrocystic disease, and adipose, was imaged with the system. The micro-CT provided visualization of the tumor mass and its spiculations, and SLI yielded superficial quantification of light scattering parameters for the malignant and benign tissue types. These results appear to be the first demonstration of SLI combined with standard medical tomography for imaging excised tumor specimens. While further investigations are needed to determine and test the spectral, spatial, and CT features required to classify tissue, this study demonstrates the ability of multimodal CT/SLI to quantify, visualize, and spatially navigate breast tumor specimens, which could potentially aid in the assessment of tumor margin status during

  15. Longitudinal in vivo evaluation of bone regeneration by combined measurement of multi-pinhole SPECT and micro-CT for tissue engineering

    Science.gov (United States)

    Lienemann, Philipp S.; Metzger, Stéphanie; Kiveliö, Anna-Sofia; Blanc, Alain; Papageorgiou, Panagiota; Astolfo, Alberto; Pinzer, Bernd R.; Cinelli, Paolo; Weber, Franz E.; Schibli, Roger; Béhé, Martin; Ehrbar, Martin

    2015-05-01

    Over the last decades, great strides were made in the development of novel implants for the treatment of bone defects. The increasing versatility and complexity of these implant designs request for concurrent advances in means to assess in vivo the course of induced bone formation in preclinical models. Since its discovery, micro-computed tomography (micro-CT) has excelled as powerful high-resolution technique for non-invasive assessment of newly formed bone tissue. However, micro-CT fails to provide spatiotemporal information on biological processes ongoing during bone regeneration. Conversely, due to the versatile applicability and cost-effectiveness, single photon emission computed tomography (SPECT) would be an ideal technique for assessing such biological processes with high sensitivity and for nuclear imaging comparably high resolution (designed poly(ethylene glycol)-based hydrogels that release bone morphogenetic protein to guide the healing of critical sized calvarial bone defects. By combined in vivo longitudinal multi-pinhole SPECT and micro-CT evaluations we determine the spatiotemporal course of bone formation and remodeling within this synthetic hydrogel implant. End point evaluations by high resolution micro-CT and histological evaluation confirm the value of this approach to follow and optimize bone-inducing biomaterials.

  16. Determination of fat tissue area in the abdomen and evaluation of degree of obesity. Pt. 2. Clinical application of a unique densitometry CT technique for determination of fat tissue areas

    International Nuclear Information System (INIS)

    Nakayama, Fumie

    1995-01-01

    Abdominal CT scanning was performed to establish normal spectra of abdominal tissue areas on 291 subjects. Using the data file of measurements of abdominal fat tissue areas of 133 normal subjects, means and their standard deviations (S.D.) were calculated for each fat tissue area at the four levels for each gender. On 158 persons with abnormal body mass index (BMI) values, S.D.-distance of each fat tissue area from the mean of the control in each age group of each gender was compared with each other. Ratios of visceral fat tissue area to subcutaneous fat tissue area (V/S ratio) were also calculated. The visceral fat tissue area of normal male subjects was significantly larger at all the four levels than those of female ones, while the subcutaneous fat tissue area were smaller at all levels. Although the area of entire and subcutaneous fat tissues of female subjects showed a peak at the age of 50 years old, those in male subjects did not show any peak at any age group. Although there was a statistically significant correlation between values of BMI and S.D.-distance of each fat tissue area at each level, the coefficient between BMI and S.D.-distance of subcutaneous fat tissue area was very low at the level of 60 mm in female. Seven of 74 female subjects with abnormal BMI had more than 10 S.D.-distance of subcutaneous fat tissue area at all levels and 8 of them had more S.D.-distance than of all fat tissue area at any level. The V/S ratio of the male subjects was significantly larger than that in female. Besides, there was no correlation between V/S ratio and S.D.-distance of visceral fat tissue area in both male and female subjects. These findings indicate that the V/S ratio does not reflect the size of fat tissue area. The determination of fat tissue areas by the abdominal CT at several levels is quite a useful way for accurate evaluation of obesity. (S.Y.)

  17. Determination of fat tissue area in the abdomen and evaluation of degree of obesity. Pt. 2. Clinical application of a unique densitometry CT technique for determination of fat tissue areas

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, Fumie [Saint Marianna Univ., Kawasaki, Kanagawa (Japan). School of Medicine

    1995-06-01

    Abdominal CT scanning was performed to establish normal spectra of abdominal tissue areas on 291 subjects. Using the data file of measurements of abdominal fat tissue areas of 133 normal subjects, means and their standard deviations (S.D.) were calculated for each fat tissue area at the four levels for each gender. On 158 persons with abnormal body mass index (BMI) values, S.D.-distance of each fat tissue area from the mean of the control in each age group of each gender was compared with each other. Ratios of visceral fat tissue area to subcutaneous fat tissue area (V/S ratio) were also calculated. The visceral fat tissue area of normal male subjects was significantly larger at all the four levels than those of female ones, while the subcutaneous fat tissue area were smaller at all levels. Although the area of entire and subcutaneous fat tissues of female subjects showed a peak at the age of 50 years old, those in male subjects did not show any peak at any age group. Although there was a statistically significant correlation between values of BMI and S.D.-distance of each fat tissue area at each level, the coefficient between BMI and S.D.-distance of subcutaneous fat tissue area was very low at the level of 60 mm in female. Seven of 74 female subjects with abnormal BMI had more than 10 S.D.-distance of subcutaneous fat tissue area at all levels and 8 of them had more S.D.-distance than of all fat tissue area at any level. The V/S ratio of the male subjects was significantly larger than that in female. Besides, there was no correlation between V/S ratio and S.D.-distance of visceral fat tissue area in both male and female subjects. These findings indicate that the V/S ratio does not reflect the size of fat tissue area. The determination of fat tissue areas by the abdominal CT at several levels is quite a useful way for accurate evaluation of obesity. (S.Y.).

  18. CT evaluation of acetabular fractures

    Energy Technology Data Exchange (ETDEWEB)

    Piazza, P; Girelli, G; Coran, F; Lutman, M

    1986-01-01

    The paper deals with sixteen cases of acetabular fractures studied with CT. After a short description of the normal CT findings, the different kind of fractures are reported. The usefulness of CT examination in evaluating acetabular fractures and their complications is confirmed both in conservative treatment and surgical approach.

  19. CT evaluation of thymus in myasthenia gravis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Guk Hee [Insung Hospital, Chuncheon (Korea, Republic of); Kang, Eun Young; Lee, Nam Joon; Suh, Won Hyuck [Korea University College of Medicine, Seoul (Korea, Republic of)

    1989-12-15

    The relationship between myasthenia gravis and the thymus was well establish and myasthenia gravis occurs in the presence of thymic hyperplasia or thymoma or occasionally in histologically normal thymus. Since not every patients with myasthenia gravis is a candidate for thymectomy, unless a thymoma is present, the differentiation of normal and hyperplastic thymus from thymoma becomes important. Authors reviewed retrospectively clinical records and chest CT scans of 18 patients with myasthenia gravis who underwent thymectomy during recent 5 years, to evaluate the role of CT scan. The results were as follows. 1 Of total 18 cases, 5 cases had normal thymus, 6 cases had thymic hyperplasia, 4 cases had benign thymoma and 3 cases had malignant thymoma. 2. Of 5 cases of normal thymus, no false positive cases were noted in CT scan. 3. Of 6 cases of thymic hyperplasia, CT findings were normal except 1 cases of thickened left thymic lobe. 4. Of 7 cases of thymoma, no false negative cases were noted in CT scan. 5. CT findings of benign thymoma were round or oval shaped, discrete, slightly enhancing soft tissue mass in anterior mediastinum. 6. CT findings of malignant thymoma were lobulated contoured, infiltrative, soft tissue mass lesion in anterior mediastinum with calcifications, pleural tumor implants, and SVC compression. CT yielded valuable information on differential diagnosis of thymoma, thymic hyperplasia and normal thymus. Also CT was a highly sensitive method in the detection of thymoma and determining the extent and invasiveness.

  20. CT evaluation of thymus in myasthenia gravis

    International Nuclear Information System (INIS)

    Kim, Guk Hee; Kang, Eun Young; Lee, Nam Joon; Suh, Won Hyuck

    1989-01-01

    The relationship between myasthenia gravis and the thymus was well establish and myasthenia gravis occurs in the presence of thymic hyperplasia or thymoma or occasionally in histologically normal thymus. Since not every patients with myasthenia gravis is a candidate for thymectomy, unless a thymoma is present, the differentiation of normal and hyperplastic thymus from thymoma becomes important. Authors reviewed retrospectively clinical records and chest CT scans of 18 patients with myasthenia gravis who underwent thymectomy during recent 5 years, to evaluate the role of CT scan. The results were as follows. 1 Of total 18 cases, 5 cases had normal thymus, 6 cases had thymic hyperplasia, 4 cases had benign thymoma and 3 cases had malignant thymoma. 2. Of 5 cases of normal thymus, no false positive cases were noted in CT scan. 3. Of 6 cases of thymic hyperplasia, CT findings were normal except 1 cases of thickened left thymic lobe. 4. Of 7 cases of thymoma, no false negative cases were noted in CT scan. 5. CT findings of benign thymoma were round or oval shaped, discrete, slightly enhancing soft tissue mass in anterior mediastinum. 6. CT findings of malignant thymoma were lobulated contoured, infiltrative, soft tissue mass lesion in anterior mediastinum with calcifications, pleural tumor implants, and SVC compression. CT yielded valuable information on differential diagnosis of thymoma, thymic hyperplasia and normal thymus. Also CT was a highly sensitive method in the detection of thymoma and determining the extent and invasiveness

  1. Determination of fat tissue area in the abdomen and evaluation of degree of obesity. Pt. 1. A unique application of a densitometric technique of computed tomography for CT values of fat tissue area

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, Fumie [Saint Marianna Univ., Kawasaki, Kanagawa (Japan). School of Medicine

    1995-06-01

    Computed tomography (CT) scanning images were taken from 26 normal subjects, 23 obesity patients and 11 with leanness to determine fat tissue values. Setting three regions of interest (ROIs) for fat tissues identified by a double-window display, a total of 52 images were employed. Histograms were constructed for each of the 3 ROIs, and the maximum, mean and minimum values were computed for each fat tissues. Areas of entire fat tissues were computed on each image with the above-cited CT software for thyroidal iodine contents by setting ROIs along the outline of body, the abdominal wall and the wall of colon, respectively. Areas of subcutaneous fat tissues were calculated by simply subtracting the values of visceral fat tissues from those of entire fat tissues. Means of maximum and minimum CT values of visceral fat tissues on 52 images were -34.7 HU and -162.1 HU, respectively. The double-window display indicated that the spectrum of CT values of fat tissue included not only visceral and subcutaneous fat tissues but fecal materials with air bubbles in the colon. Areas of fecal materials with the same CT values as that of the fat tissues occupied 2.5{+-}3.0% of that of the visceral fat tissue. The areas of subcutaneous and visceral fat tissues were largest at the levels of -20 to 0 mm and 60 to 100 mm, respectively, on all images. At the level of 0 mm, the areas of visceral fat tissue did not show any differences among normal subjects, obesity patients and patients with leanness. It was concluded that the CT software is applicable to obtain satisfactory values for areas of visceral fat tissue, and that CT images at the levels of 0, 40, 60 and 100 mm are necessary to accurately determine areas of visceral fat tissues. (S.Y.).

  2. Determination of fat tissue area in the abdomen and evaluation of degree of obesity. Pt. 1. A unique application of a densitometric technique of computed tomography for CT values of fat tissue area

    International Nuclear Information System (INIS)

    Nakayama, Fumie

    1995-01-01

    Computed tomography (CT) scanning images were taken from 26 normal subjects, 23 obesity patients and 11 with leanness to determine fat tissue values. Setting three regions of interest (ROIs) for fat tissues identified by a double-window display, a total of 52 images were employed. Histograms were constructed for each of the 3 ROIs, and the maximum, mean and minimum values were computed for each fat tissues. Areas of entire fat tissues were computed on each image with the above-cited CT software for thyroidal iodine contents by setting ROIs along the outline of body, the abdominal wall and the wall of colon, respectively. Areas of subcutaneous fat tissues were calculated by simply subtracting the values of visceral fat tissues from those of entire fat tissues. Means of maximum and minimum CT values of visceral fat tissues on 52 images were -34.7 HU and -162.1 HU, respectively. The double-window display indicated that the spectrum of CT values of fat tissue included not only visceral and subcutaneous fat tissues but fecal materials with air bubbles in the colon. Areas of fecal materials with the same CT values as that of the fat tissues occupied 2.5±3.0% of that of the visceral fat tissue. The areas of subcutaneous and visceral fat tissues were largest at the levels of -20 to 0 mm and 60 to 100 mm, respectively, on all images. At the level of 0 mm, the areas of visceral fat tissue did not show any differences among normal subjects, obesity patients and patients with leanness. It was concluded that the CT software is applicable to obtain satisfactory values for areas of visceral fat tissue, and that CT images at the levels of 0, 40, 60 and 100 mm are necessary to accurately determine areas of visceral fat tissues. (S.Y.)

  3. Evaluation of Bone Metastasis from Hepatocellular Carcinoma Using {sup 18F} FDG PET/CT and {sup 99mT}c HDP Bone Scintigraphy: Characteristics of Soft Tissue Formation

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Hyo Jung; Choi, Yun Jung; Kim, Hyun Jeong; Jeong, Youg Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Choi, Hye Jin; Lee, Jong Doo; Kang, Won Jun [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    2011-09-15

    Bone metastasis from hepatocellular carcinoma (HCC) can present with soft tissue formation, resulting in oncologic emergency. Contrast enhanced FDG PET/CT and bone scintigraphy were compared to evaluate characteristics of bone metastases with of without soft tissue formation from HCC. of 4,151 patients with HCC, 263 patients had bone metastases. Eighty five patients with bone metastasis from HCC underwent contrast enhanced FDG PET/CT. Fifty four of the enrolled subjects had recent {sup 99mT}c HDP bone scintigraphy available for comparison. Metastatic bone lesions were identified with visual inspection on FDG PET/CT, and maximum standardized uptake value (SUVmax) was used for the quantitative analysis. Confirmation of bone metastasis was based on histopathology, combined imaging modalities, or serial follow up studies. Forty seven patients (55%) presented with soft tissue formation, while the remaining 38 patients presented without soft tissue formation. Frequent sites of bone metastases from HCC were the spine (39%), pelvis (19%), and rib cage (14%). The soft tissue formation group had more frequent bone pain (77 vs. 37%, p<0.0001), higher SUVmax (6.02 vs. 3.52, p<0.007), and higher incidence of photon defect in bone scintigraphy (75 vs. 0%) compared to the non soft tissue formation group. FDG PET/CT had higher detection rate for bone metastasis than bone scintigraphy both in lesion based analysis (98 vs. 53%, p=0.0015) and in patient based analysis (100 vs. 80%, p<0.001). Bone metastasis from HCC showed a high incidence of soft tissue formation requiring emergency treatment. Although the characteristic findings for soft tissue formation such as photon defect in bone scintigraphy are helpful in detection, overall detectability of bone metastasis is higher in FDG PET/CT. Contrast enhanced PET/CT will be useful in finding and delineating soft tissue forming bone metastasis from HCC.

  4. Mixed connective tissue disease associated with noted pulmonary CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Souji; Tsukada, Atsuko; Furuya, Tatsutaka

    1984-10-01

    CT was performed in a 56-year-old woman with mixed connective tissue disease (MCTD). Much more definitive pulmonary findings were obtained by CT than by the conventional chest x-ray examination and pulmonary function test. CT findings disclosed pulmonary lesions extremely similar to those in cases of progressive systemic sclerosis. Pulmonary CT was considered useful in examining pulmonary lesions for MCTD.

  5. Evaluating differential nuclear DNA yield rates and osteocyte numbers among human bone tissue types: A synchrotron radiation micro-CT approach.

    Science.gov (United States)

    Andronowski, Janna M; Mundorff, Amy Z; Pratt, Isaac V; Davoren, Jon M; Cooper, David M L

    2017-05-01

    Molecular human identification has conventionally focused on DNA sampling from dense, weight-bearing cortical bone tissue, typically from femora or tibiae. A comparison of skeletal elements from three contemporary individuals demonstrated that elements with high quantities of cancellous bone yielded nuclear DNA at the highest rates, suggesting that preferentially sampling cortical bone may be suboptimal (Mundorff & Davoren, 2014). Despite these findings, the reason for the differential DNA yields between cortical and cancellous bone tissues remains unknown. The primary goal of this work is to ascertain whether differences in bone microstructure can be used to explain differential nuclear DNA yield among bone tissue types observed by Mundorff and Davoren (2014), with a focus on osteocytes and the three-dimensional (3D) quantification of their associated lacunae. Osteocytes and other bone cells are recognized to house DNA in bone tissue, thus examining the density of their lacunae may explain why nuclear DNA yield rates differ among bone tissue types. Lacunae were visualized and quantified using synchrotron radiation-based micro-Computed Tomographic imaging (SR micro-CT). Volumes of interest (VOIs) from cortical and cancellous bone tissues (n=129) were comparatively analyzed from the three skeletons sampled for Mundorff and Davoren's (2014) study. Analyses tested the primary hypothesis that the abundance and density of osteocytes (inferred from their lacunar spaces) vary between cortical and cancellous bone tissue types. Results demonstrated that osteocyte lacunar abundance and density vary between cortical and cancellous bone tissue types, with cortical bone VOIs containing a higher lacunar abundance and density. We found that the osteocyte lacunar density values are independent of nuclear DNA yield, suggesting an alternative explanation for the higher nuclear DNA yields from bones with greater quantities of cancellous bone tissue. The use of SR micro-CT allowed for

  6. CT evaluation of abdominal trauma

    International Nuclear Information System (INIS)

    Huang Ruiting

    2004-01-01

    Objective: An evaluation of CT diagnosis of abdominal trauma. Methods: CT appearance of abdominal trauma was analyzed retrospectively in 95 cases. thirty-three patients were cured by operation, and the other 59 patients received conservative treatment. Fifty-one patients out of 59 were seen healed or improved by a follow up CT scan after the conservative treatment. Results: The study included: 31 cases of splenic contusion, accompanying with hemoperitoneum in 25 cases; 3 cases of hepatic laceration; 33 cases of liver and spleen compound trauma accompanying with hemoperitoneum; 18 cases of renal contusion, with subcapsular hemorrhage in 12 cases; 4 cases of midriff colic; 3 cases of mesentery breach; 3 cases of digestive tract perforation. Conclusion: CT is sensitive and precise in evaluating abdominal trauma, providing important information for treatment. (author)

  7. Radical pancreatectomy: postoperative evaluation by CT

    Energy Technology Data Exchange (ETDEWEB)

    Heiken, J.P.; Balfe, D.M.; Picus, D.; Scharp, D.W.

    1984-10-01

    Twenty-four patients who had undergone radical pancreatic resection were evaluated by CT one week to 11 years after surgery. Eighteen patients had had the Whipple procedure; six had had total pancreatectomy. The region between the aorta and superior mesenteric artery, previously occupied by the uncinate process of the pancreas, is an important area to evaluate for tumor recurrence because periampullary tumors tend to metastasize to the lymph nodes in this region. Tumor recurrence here is readily detectable by CT since radical pancreatectomy leaves this area area free of soft tissue attenuation material. CT demonstrated postoperative complications or tumor recurrence in 16 of the 24 patients and was 100% accurate in patients who had follow-up.

  8. Radical pancreatectomy: postoperative evaluation by CT

    International Nuclear Information System (INIS)

    Heiken, J.P.; Balfe, D.M.; Picus, D.; Scharp, D.W.

    1984-01-01

    Twenty-four patients who had undergone radical pancreatic resection were evaluated by CT one week to 11 years after surgery. Eighteen patients had had the Whipple procedure; six had had total pancreatectomy. The region between the aorta and superior mesenteric artery, previously occupied by the uncinate process of the pancreas, is an important area to evaluate for tumor recurrence because periampullary tumors tend to metastasize to the lymph nodes in this region. Tumor recurrence here is readily detectable by CT since radical pancreatectomy leaves this area area free of soft tissue attenuation material. CT demonstrated postoperative complications or tumor recurrence in 16 of the 24 patients and was 100% accurate in patients who had follow-up

  9. Malignant external otitis: CT evaluation

    International Nuclear Information System (INIS)

    Curtin, H.D.; Wolfe, P.; May, M.

    1982-01-01

    Malignant external otitis is an aggressive infection caused by Pseudomonas aeruginosa that most often occurs in elderly diabetics. Malignant external otitis often spreads inferiorly from the external canal to involve the subtemporal area and progresses medially towards the petrous apex leading to multiple cranial nerve palsies. The computed tomographic (CT) findings in malignant external otitis include obliteration of the normal fat planes in the subtemporal area as well as patchy destruction of the bony cortex of the mastoid. The point of exit of the various cranial nerves can be identified on CT scans, and the extent of the inflammatory mass correlates well with the clinical findings. Four cases of malignant external otitis are presented. In each case CT provided a good demonstration of involvement of the soft tissues at the base of the skull

  10. Helical 3D-CT images of soft tissue tumors in the hand

    Energy Technology Data Exchange (ETDEWEB)

    Otani, Kazuhiro; Kikuchi, Hiraku; Tan, Akihiro; Hamanishi, Chiaki; Tanaka, Seisuke [Kinki Univ., Osaka-Sayama (Japan). School of Medicine

    2000-02-01

    X-ray, ultrasonograph CT, MRI and angiography are used to detect tumoral lesions. Recently, helical CT has been revealed to be a useful method for the diagnosis and preoperative evaluation of soft tissue tumors, by which high quality and accurate three dimensional (3D) images can be obtained quickly. We analyzed the preoperative 3D-CT images of soft tissue tumors in the hands of 11 cases (hemangioma in 6 cases, giant cell tumor, lipoma, angiofibroma, chondrosarcoma and malignant fibro-histiocytoma in one case each). Enhanced 3D-CT clearly visualized hemangiomas and solid tumors from the surrounding tissues. The tumors could easily be observed from any direction and color-coded according to the CT number. Helical 3D-CT was thus confirmed to be useful for the diagnosis and preoperative planning by indicating the details of tumor expansion into surrounding tissues. (author)

  11. Mixed connective tissue disease associated with noted pulmonary CT findings

    International Nuclear Information System (INIS)

    Yamazaki, Souji; Tsukada, Atsuko; Furuya, Tatsutaka

    1984-01-01

    CT was performed in a 56-year-old woman with mixed connective tissue disease (MCTD). Much more definitive pulmonary findings were obtained by CT than by the conventional chest x-ray examination and pulmonary function test. CT findings disclosed pulmonary lesions extremely similar to those in cases of progressive systemic sclerosis. Pulmonary CT was considered useful in examining pulmonary lesions for MCTD. (Namekawa, K.)

  12. CT findings of pulmonary mucosa-associated lymphoid tissue lymphoma

    International Nuclear Information System (INIS)

    Zhang Weidong; Guan Yubao; Li Chuanxing; Wu Peihong

    2010-01-01

    Objective: To study the CT findings of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma. Methods: The CT examinations of 12 patients with pathologically proven pulmonary MALT lymphoma were reviewed retrospectively. Evaluated imaging findings included number, distribution, shape, attenuation and other associated findings of each lesion were evaluated. Results: Thirty-two pulmonary lesions, including consolidations, masses, nodules and lesions with ground glass attenuation, were identified in 12 patients. Multiple lesions were founded in 10 of 12 patients and solitary lesion in 2 patients. Multiple lesions found in one lung in 2 patients, and multiple lesions found in both lungs in 8 patients. Ten cases demonstrated 21 consolidation lesions with air bronchogram, and one of the ten cases demonstrated two lesions with airway dilatation. Three cases demonstrated 5 masses or nodular lesions, 3 of these 5 lesions showed air bronchogram. Two cases demonstrated 6 ground glass attenuation lesions. One case showed mediastinal and hilar lymphadenopathy. Conclusion: Pulmonary MALT lymphoma usually appears as multiple bilateral consolidations, masses, nodules with air bronchogram or lesions with ground- glass attenuation at CT imaging. The imaging findings described above and with an indolent clinical course may suggest the diagnosis of pulmonary MALT lymphoma. (authors)

  13. Branchial cleft anomalies: CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Seok, Eul Hye; Park, Chan Sup [College of Medicine, Inha University, Seongnam (Korea, Republic of)

    1994-04-15

    The purpose of this paper is to describe the CT findings of a variety of branchial cleft anomalies in the head and neck area. We reviewed the CT findings of 16 patients with neck lesion pathologically proved as branchial cleft anomalies. There were two first and 12 second branchial cleft cysts, one first and one second branchial cleft sinuses. Two cases of first branchial cleft cysts were manifested as thin-walled, cystic masses at auricular area. One first branchial cleft sinus was an external opening type and manifested as an ill-defined, enhancing solid lesion at posterior auricular area. All 12 cases of second branchial cleft cysts demonstrated a typical location, displacing the sternocleidomastoid muscle posteriorly, the carotid artery and internal jugular vein complex medially and the submandibular gland anteriorly. Eight cases of second branchial cleft cysts were seen as fluid-filled, round or ovoid-shaped cysts, and 3 cases of them were seen as irregular-shaped cysts. In one case, suppurative adenopathy with loss of soft tissue planes around the cyst was observed. One case of second branchial cleft sinus was manifested as a tubular-shaped, enhancing lesion at submental area and containing external opening site draining into the anterior border of the sternocleidomastoid muscle. We conclude that CT provides important diagnostic and therapeutic information in patients with a neck mass believed to be a branchial cleft anomaly, as it can differentiate various forms of the branchial anomalies by their characteristic location and shape.

  14. Branchial cleft anomalies: CT evaluation

    International Nuclear Information System (INIS)

    Seok, Eul Hye; Park, Chan Sup

    1994-01-01

    The purpose of this paper is to describe the CT findings of a variety of branchial cleft anomalies in the head and neck area. We reviewed the CT findings of 16 patients with neck lesion pathologically proved as branchial cleft anomalies. There were two first and 12 second branchial cleft cysts, one first and one second branchial cleft sinuses. Two cases of first branchial cleft cysts were manifested as thin-walled, cystic masses at auricular area. One first branchial cleft sinus was an external opening type and manifested as an ill-defined, enhancing solid lesion at posterior auricular area. All 12 cases of second branchial cleft cysts demonstrated a typical location, displacing the sternocleidomastoid muscle posteriorly, the carotid artery and internal jugular vein complex medially and the submandibular gland anteriorly. Eight cases of second branchial cleft cysts were seen as fluid-filled, round or ovoid-shaped cysts, and 3 cases of them were seen as irregular-shaped cysts. In one case, suppurative adenopathy with loss of soft tissue planes around the cyst was observed. One case of second branchial cleft sinus was manifested as a tubular-shaped, enhancing lesion at submental area and containing external opening site draining into the anterior border of the sternocleidomastoid muscle. We conclude that CT provides important diagnostic and therapeutic information in patients with a neck mass believed to be a branchial cleft anomaly, as it can differentiate various forms of the branchial anomalies by their characteristic location and shape

  15. Evaluation of CT in hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Nakao, Norio; Miura, Yukio; Ohnishi, Mitsunori; Kamikon-ya, Norihiko; Sakamoto, Yoshisato; Miura, Takashi; Sakamoto, Kiyoshi; Takayasu, Yoshio

    1985-06-01

    In order to evaluate the diagnostic ability of CT in hepatocellular carcinoma, four kinds of CT images were comparatively studied by the accuracy and ROC (receiver operating characteristic) curve analysis. As a result, it was clarified that CT images were evaluated more objectively by ROC curve analysis than by accuracy. The diagnostic ability of existence and differentiation of tumor in the liver were higher in order of plain CT, contrast enhanced CT (CECT), bolus CT and CT arteriography (CTA). Therefore, in an usual CT examination intended to make differential diagnosis in space occupying liver disease, bolus CT seems to be indispensable, and also CTA is essential where diagnosis is difficult even by bolus CT.

  16. CT evaluation of infectious colitis

    International Nuclear Information System (INIS)

    Horiki, Noriyuki; Maruyama, Masataka; Fujita, Yoshiyuki; Suzuki, Yuko; Tanaka, Tsuyoshi; Imoto, Ichiro; Adachi, Yukihiko

    2002-01-01

    Computed tomography (CT) is useful for evaluating the diagnosis of gastrointestinal disease, such as infectious colitis, in patients with severe pain and bloody diarrhea. During the 7 years between November 1993 and October 2000, 34 patients with infectious colitis (18 male, 16 female; mean age 42±19 yrs), received emergency CT and colonoscopy because of severe abdominal pain and dysentery. The following organisms were isolated: pathogenic Escherichia coli (12), 6 of which were O157: H7 (O-157), Salmonella species (11), Campylobacter species (5), Vibrio parahaemolyticus (3), Yersinia enterocolotica (2) and Shigella species (1). Thickening of the intestinal wall greater than 10 mm was seen in the ascending colon in the 6 cases with E. coli O157, in 5/11 cases with Salmonella, 4/5 with Campylobacter and 1/6 with non-O157 pathogenic E. Coli. marked intestinal wall thickening, greater than 20 mm, was seen in the ascending colon of the 4 of the patients with an O-157 infection. In all patients with O-157 colitis, slight ascites was noted in the pelvic space. In additions, ascites was also seen in 3/13 patients with Salmonella and 1/5 patients with Campylobacter colitis. The CT findings, in the patients with infectious colitis, are non-specific but knowledge and recognition of the findings will help in patient evaluation and proper treatment. (author)

  17. CT evaluation of infectious colitis

    Energy Technology Data Exchange (ETDEWEB)

    Horiki, Noriyuki; Maruyama, Masataka; Fujita, Yoshiyuki; Suzuki, Yuko [Saint Luke' s International Hospital, Tokyo (Japan); Tanaka, Tsuyoshi; Imoto, Ichiro [National Mie Chuo Hospital, Hisai (Japan); Adachi, Yukihiko [Mie Univ., Tsu (Japan). School of Medicine

    2002-08-01

    Computed tomography (CT) is useful for evaluating the diagnosis of gastrointestinal disease, such as infectious colitis, in patients with severe pain and bloody diarrhea. During the 7 years between November 1993 and October 2000, 34 patients with infectious colitis (18 male, 16 female; mean age 42{+-}19 yrs), received emergency CT and colonoscopy because of severe abdominal pain and dysentery. The following organisms were isolated: pathogenic Escherichia coli (12), 6 of which were O157: H7 (O-157), Salmonella species (11), Campylobacter species (5), Vibrio parahaemolyticus (3), Yersinia enterocolotica (2) and Shigella species (1). Thickening of the intestinal wall greater than 10 mm was seen in the ascending colon in the 6 cases with E. coli O157, in 5/11 cases with Salmonella, 4/5 with Campylobacter and 1/6 with non-O157 pathogenic E. Coli. marked intestinal wall thickening, greater than 20 mm, was seen in the ascending colon of the 4 of the patients with an O-157 infection. In all patients with O-157 colitis, slight ascites was noted in the pelvic space. In additions, ascites was also seen in 3/13 patients with Salmonella and 1/5 patients with Campylobacter colitis. The CT findings, in the patients with infectious colitis, are non-specific but knowledge and recognition of the findings will help in patient evaluation and proper treatment. (author)

  18. FDG PET/CT对骨及软组织肿瘤诊断和疗效评价的应用%FDG PET/CT imaging in the diagnosis and efficacy evaluation for bone and soft tissue tumors

    Institute of Scientific and Technical Information of China (English)

    刘健; 赵涛; 吕杰; 孙波; 张鹏

    2011-01-01

    Objective To assess the clinical value of FDG PET/CT imaging in the diagnosis and efficacy evaluation for bone and soft tissue tumors.Methods The FDG PET/CT images of 48 patients diagnosed with bone and soft tissue tumors were retrospectively analyzed.These FDG PET/CT images were analyzed in order to differentially diagnose the tumors to be benign or malignant, and to confirm whether there was recurrence, distal metastasis and surrounding invasion or not.Besides, comparative analysis was done between the FDG PET/CT imaging and the CT imaging.Results For FDG PET/CT imaging in the diagnosis for bone and soft tissue tumors, the rate of sensitivity was10O% (7/7), and the rate of specificity was 80% (4/5).According to the monitoring results of recurrence and residual,both the post-operative rate of sensitivity and the post-operative rate of specificity were 1O0%.Extra 35 metastases were detected by the PET/CT imaging, and the other 12 pulmonary metastases were found by the CT imaging.Conclusions FDG PET/CT imaging in the diagnosis for bone and soft tissue tumors is better than the routine imaging.It can accurately detect the recurrence of tumors in the early stage, and find extra metastasis (except pulmonary metastasis).Therefore, it can assist the treatment and diagnosis against tumors.%目的 探讨FDG PET/CT显像诊断骨或软组织肿瘤和术后疗效评价的价值.方法 回顾性分析48例已证实的骨及软组织肿瘤患者的FDG PET/CT显像结果,以鉴别诊断肿瘤的良恶性,是否复发、有无其他转移及周围侵犯,并与同机CT对比分析.结果 FDG PET/CT显像诊断骨及软组织肿瘤灵敏度为100%(7/7),特异性为80%(4/5);监测术后复发(残留)的灵敏度和特异性均为100%;通过PET/CT显像多发现转移灶35处,对于肺部12个转移灶,有赖于同机CT.结论 FDG PET/CT显像对骨及软组织肿瘤的诊断优于常规影像检查,可早期准确判断肿瘤复发,同时发现更多转移灶(肺转移除

  19. CT in the evaluation of pelvic trauma

    International Nuclear Information System (INIS)

    Federle, M.P.

    1986-01-01

    Pelvic fractures from motor vehicle accidents are a cause of substantial morbidity and permanent disability, and are the third leading cause of death following blunt trauma. Associated extremity fractures are common, and injury to abdominal and pelvic viscera may occur. Difficulty in establishing the source of hemorrhage may be encountered, especially since pelvic fractures with extraperitoneal bleeding may result in intraperitoneal bleeding through torn fascial planes. The difficulty in properly diagnosing and managing complex fractures of the pelvis and acetabulum is well documented. Prognosis is influenced by the type and extent of pelvic fracture and associated soft tissue injuries. Computed tomography (CT) has proved to be a valuable tool in evaluation of these complex and life-threatening injuries

  20. Complicated pleural tuberculosis in children: CT evaluation

    International Nuclear Information System (INIS)

    Moon, W.K.; Kim, W.S.; Kim, I.O.; Im, J.G.; Kim, J.H.; Yeon, K.M.; Han, M.C.

    1999-01-01

    Purpose. To describe the CT features of complicated pleural tuberculosis in children and to define the use of CT in children with pleural tuberculosis. Materials and methods. The CT findings in 11 children with complicated pleural tuberculosis were retrospectively analysed. CT was performed to evaluate persistent pleural thickening (n = 6) or a mass-like lesion (n = 5) detected on plain radiographs. Chest radiographs and medical records were reviewed to determine whether additional information provided by CT had altered clinical management. Results. On CT, more than one location was involved in five patients (45 %) and in two patients (18 %) the entire pleural spaces were involved. Pleural thickening was seen in all 11 patients and enhancement after administration of contrast medium occurred in ten patients (91 %). Low-density fluid collections were seen in nine patients (82 %) and in two, CT revealed fluid collections within calcified pleural lesions. In five patients with mass-like lesions on plain radiographs, CT showed a low-density pleural mass with peripheral enhancement in four and a calcified pleural mass with fluid collection in one. CT demonstrated parenchymal abnormalities on the same side as pleural lesions in all 11 patients and hilar or mediastinal adenopathy in four. Four patients (36 %) underwent surgery because of fluid within a calcified fibrothorax (n = 3) and chest wall tuberculosis (n = 1) that were seen only on CT. Conclusions. The CT features of complicated pleural tuberculosis in children were pleural thickening, enhancement and fluid collection with associated parenchymal abnormalities and lymphadenopathy. In the evaluation of children with pleural tuberculosis, CT can be useful for demonstrating fluid within a calcified fibrothorax or chest wall involvement, which usually requires surgical intervention. (orig.)

  1. CT appearances of mucosa-associated lymphoid tissue (MALT) lymphoma

    International Nuclear Information System (INIS)

    Kessar, P.; Norton, A.; Rohatiner, A.Z.S.; Lister, T.A.; Reznek, R.H.

    1999-01-01

    Mucosa-associated lymphoid tissue (MALT) lymphoma is a low-grade lymphoma that differs from high-grade non-Hodgkin lymphoma both clinically and histologically. The CT appearances of MALT lymphoma are described. Of 40 patients referred with biopsy-proven MALT lymphoma, only seven had not had gastrectomy or chemotherapy prior to CT examination. The CT scans of these seven cases were analysed for the degree and extent of gastric wall thickening, enlargement of abdominal and extra-abdominal lymph nodes, and presence of extranodal disease. In all patients the stomach was distended with oral contrast medium and scans performed at narrow collimation, after intravenous administration of 20 mg hyoscine butylbromide. In six patients focal thickening of the gastric wall was 1 cm or less. One patient had thickening of over 4 cm. There was no enlargement of abdominal or extra-abdominal lymph nodes or extension to adjacent organs. Thus on CT, at presentation, MALT lymphoma results in minimal gastric wall thickening, unlike high-grade non-Hodgkin lymphoma, which typically causes bulky gastric disease, nodal enlargement and extension into adjacent organs. CT is therefore of limited value in monitoring response to treatment. With disease greater than minimal thickening, transformation to a higher grade should be considered. (orig.)

  2. CT Imaging of facial trauma. The role of different types of reconstruction. Part II - soft tissues

    International Nuclear Information System (INIS)

    Myga-Porosilo, J.; Sraga, W.; Borowiak, H.; Jackowska, Z.; Kluczewska, E.; Skrzelewski, S.

    2011-01-01

    Background: Injury to facial soft tissues as a complication of skeleton fractures is an important problem among patients with facial trauma. The aim of this work was to assess the value of multiplanar and three-dimensional (3D) reconstruction computed tomography (CT) images obtained by using multi-detector row technology in spiral data acquisition in patients with facial injuries of soft tissue. Material/Methods: Sixty-seven patients diagnosed with injury to the facial skeleton underwent a CT scan with the use of GE Hispeed Qx/i scanner. For each patient: a two-dimensional (2D) multiplanar reconstruction (MPR), maximum intensity projection (MIP), and 3D volume rendering (VR) were conducted. Post-injury lesions of soft tissues were assessed. During the assessment of the post-injury lesions of soft tissues, the following features were evaluated: Extra ocular muscle and fat tissue herniation through fractures in the medial and inferior orbital walls. Fluid in the sinuses and in the nasal cavity. Subcutaneous tissue emphysema. Results: For subcutaneous emphysema and sinus fluid imaging, both the axial and the 2D image reconstruction proved comparably effective. However, 2D reconstructions were superior to transverse plane images with regard to herniations into fractures of the inferior orbital wall. 3D reconstruction has no importance in diagnosing soft tissue injuries. Conclusions: Multiplanar CT reconstructions increase the effectiveness of imaging of orbital tissue herniations, especially in case of fractures in the inferior orbital wall. In suspected soft tissue herniations, as well as prior to surgical treatment, spiral CT with 2D multiplanar reconstructions should be the method of choice. (authors)

  3. Optimization of CT image reconstruction algorithms for the lung tissue research consortium (LTRC)

    Science.gov (United States)

    McCollough, Cynthia; Zhang, Jie; Bruesewitz, Michael; Bartholmai, Brian

    2006-03-01

    To create a repository of clinical data, CT images and tissue samples and to more clearly understand the pathogenetic features of pulmonary fibrosis and emphysema, the National Heart, Lung, and Blood Institute (NHLBI) launched a cooperative effort known as the Lung Tissue Resource Consortium (LTRC). The CT images for the LTRC effort must contain accurate CT numbers in order to characterize tissues, and must have high-spatial resolution to show fine anatomic structures. This study was performed to optimize the CT image reconstruction algorithms to achieve these criteria. Quantitative analyses of phantom and clinical images were conducted. The ACR CT accreditation phantom containing five regions of distinct CT attenuations (CT numbers of approximately -1000 HU, -80 HU, 0 HU, 130 HU and 900 HU), and a high-contrast spatial resolution test pattern, was scanned using CT systems from two manufacturers (General Electric (GE) Healthcare and Siemens Medical Solutions). Phantom images were reconstructed using all relevant reconstruction algorithms. Mean CT numbers and image noise (standard deviation) were measured and compared for the five materials. Clinical high-resolution chest CT images acquired on a GE CT system for a patient with diffuse lung disease were reconstructed using BONE and STANDARD algorithms and evaluated by a thoracic radiologist in terms of image quality and disease extent. The clinical BONE images were processed with a 3 x 3 x 3 median filter to simulate a thicker slice reconstructed in smoother algorithms, which have traditionally been proven to provide an accurate estimation of emphysema extent in the lungs. Using a threshold technique, the volume of emphysema (defined as the percentage of lung voxels having a CT number lower than -950 HU) was computed for the STANDARD, BONE, and BONE filtered. The CT numbers measured in the ACR CT Phantom images were accurate for all reconstruction kernels for both manufacturers. As expected, visual evaluation of the

  4. Evaluation strategies in CT scanning

    DEFF Research Database (Denmark)

    In this talk, dimensional measurement results using different measuring strategies applied in different inspection software packages for volume and surface data analysis are presented. The influence of the strategy on the dimensional measurement is determined by calculating the measurement...... uncertainty. This investigation includes measurements of two industrial items, an aluminum pipe connector and a plastic toggle, a hearing aid component. These are measured using a commercial CT scanner. Traceability is transferred using tactile and optical coordinate measuring machines, which are used...

  5. Soft tissue metastases from differentiated thyroid cancer diagnosed by {sup 18}F FDG PET-CT

    Energy Technology Data Exchange (ETDEWEB)

    Califano, Ines; Quildrian, Sergio; Otero, Jose; Coduti, Martin; Califano, Leonardo; Rojas Bilbao, Erica, E-mail: ines.m.califano@gmail.com [Instituto de Oncologia Angel H. Roffo, Universidad de Buenos Aires (Argentina)

    2013-06-15

    Distant metastases of differentiated thyroid cancer are unusual; lung and bones are the most frequently affected sites. Soft tissue metastases (STM) are extremely rare. We describe two cases of patients with differentiated thyroid cancer metastasizing to soft tissues. Both patients had widespread metastatic disease; clinically asymptomatic soft tissue metastases were found by 18-Fluorodeoxyglucose positron emission tomography/computed tomography ({sup 18}F FDG PET-CT), and confirmed by cytological and/or histopathological studies. These findings underscore the ability of {sup 18}F FDG PET-CT in accurately assessing the extent of the disease, as well as the utility of the method to evaluate regions of the body that are not routinely explored. (author)

  6. Peripheral facial nerve dysfunction: CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Disbro, M.A.; Harnsberger, H.R.; Osborn, A.G.

    1985-06-01

    Peripheral facial nerve dysfunction may have a clinically apparent or occult cause. The authors reviewed the clinical and radiographic records of 36 patients with peripheral facial nerve dysfunction to obtain information on the location of the suspected lesion and the number, sequence, and type of radiographic evaluations performed. Inadequate clinical evaluations before computed tomography (CT) was done and unnecessary CT examinations were also noted. They have suggested a practical clinical and radiographic scheme to evaluate progressive peripheral facial dysfunction with no apparent cause. If this scheme is applied, unnecessary radiologic tests and delays in diagnosis and treatment may be avoided.

  7. Strategies for CT tissue segmentation for Monte Carlo calculations in nuclear medicine dosimetry

    DEFF Research Database (Denmark)

    Braad, P E N; Andersen, T; Hansen, Søren Baarsgaard

    2016-01-01

    in the ICRP/ICRU male phantom and in a patient PET/CT-scanned with 124I prior to radioiodine therapy. Results: CT number variations body CT examinations at effective CT doses ∼2 mSv. Monte Carlo calculated absorbed doses depended on both the number of media types and accurate......Purpose: CT images are used for patient specific Monte Carlo treatment planning in radionuclide therapy. The authors investigated the impact of tissue classification, CT image segmentation, and CT errors on Monte Carlo calculated absorbed dose estimates in nuclear medicine. Methods: CT errors...

  8. CT and MRI Findings of Soft Tissue Adult Fibrosarcoma in Extremities

    Directory of Open Access Journals (Sweden)

    Hexiang Wang

    2018-01-01

    Full Text Available Objective. To characterize and evaluate CT and MRI features of extremity soft tissue adult fibrosarcoma. Methods. CT and MRI images from 10 adult patients with pathologically proven fibrosarcomas were retrospectively analyzed with regard to tumor location, size, number, shape, margins, attenuation, signal intensity, and enhancement patterns on MR images. Additionally, the relationships between lesions, deep fascia, and change in adjacent bones were also assessed. Results. Nineteen tumor lesions in 10 patients were selected for this study. Eighteen lesions were lobulated and one was oval in shape. Most cases were located under the deep fascia, including seven cases that had a nodular lump adjacent to the deep fascia and one case that had broken lesion through the deep fascia. On CT, the adult fibrosarcomas mostly showed iso-attenuated soft tissue masses (n=6. On MRI, all the cases (n=9 displayed low signal on T1-weighted imaging (T1WI and heterogeneous low and high intensity signals on T2-weighted imaging (T2WI, with band-like areas of low signal on both T1WI and T2WI. On contrast-enhanced MRI images, three cases showed heterogeneous peripheral enhancement and one case demonstrated a spoke-wheel-like enhancement. Eight cases showed muscle edema signals in the peritumoral muscle and one case involved adjacent bone. Conclusion. CT and MR imaging have respective advantages in diagnosing adult fibrosarcoma. Combined application of CT and MR is recommended for patients with suspected adult fibrosarcoma.

  9. X-ray CT evaluation of pulmonary involvements of sarcoidosis

    International Nuclear Information System (INIS)

    Nishimura, Koichi; Izumi, Takateru; Kitaichi, Masanori

    1987-01-01

    We evaluated high resolution CT in 60 patients with histologically diagnosed pulmonary sarcoidosis and, also, studied the relationship between CT and findings in open lung biopsy specimens in 2 cases. The CT findings were as follows: (1) thickening of bronchial wall shadows (27 out of 60 cases, 45.0 %), (2) irregular enlargement of pulmonary vascular shadows (39 cases, 65.0 %), (3) small or large nodular shadows (24 cases, 40.0 %), (4) local volume loss (14 cases, 23.3 %), (5) slightly increased density of localized lung field areas (24 cases, 40.0 %), (6) pleural or subpleural involvement (27 cases, 45.0 %), (7) lymph node enlargement (59 cases, 98.3 %). X-ray CT in 7 patients revealed no evidence of lung field involvement in patients with histologicall confirmed epithelioid cell granuloma in transbronchial lung biopsy specimens. Lesions located within vessels or in the vascular wall, perivascular sheath or alveoli surrounding blood vessels might cause pulmonary vascular shadows to appear swollen on CT. In a comparative study, we found irregular dilatation of pulmonary vascular shadows corresponding to granulomas in the connective tissue sheath of blood vessels. Also, thickening of bronchial wall shadows corresponded to granulomas in and around the bronchial wall. From the point of histopathological view epithelioid cell granulomas in the bronchovascular sheath were most marked in sarcoidosis, and they apperaed on CT as an irregular enlargement of pulmonary vascular shadows and thickening of the bronchial wall. On the other hand, we reported that collapse of alveoli and fibrosis surrounding blood vessels could cause irregular enlargement of pulmonary vascular shadows on CT in idiopathic pulmonary fibrosis (IPF). Such shadows were seen on CT in both sarcoidosis and IPF but the mechanism of their appearance differed. (J.P.N.)

  10. PET-CT in the evaluation of metastatic breast cancer

    International Nuclear Information System (INIS)

    Sullivan, A.M.; Fulham, M.J.

    2005-01-01

    A 44-year-old woman underwent two PET-CT scans for the evaluation of metastatic breast cancer. A radical left mastectomy with axillary dissection (1 of 43 nodes positive) followed by chemotherapy, was performed in 1998. She represented in October 2003 with a left supraclavicular fossa mass. This was confirmed to be recurrent breast cancer on FNAB. She was considered for a radical neck dissection and the surgeon requested a PET scan. Other imaging at this time included a normal bone scan and CT brain. CT neck/chest/abdomen/pelvis showed soft tissue thickening in the left lower neck. The PET-CT scan showed multiple glucose avid lesions in the sternum, mediastinum and neck lymph nodes as well as a small lesion in the proximal left femur consistent with extensive metastatic disease. Surgery was cancelled and Femara chemotherapy commenced. Femara was stopped in March 2004 and the patient began alternative therapies. In October 2004 she presented to her surgeon with new back and chest pain. CT of the neck/chest/abdomen/pelvis showed a soft tissue mass in the upper sternum and a lymph node at the base of the neck highly suspicious for metastatic disease. There were also 2 suspicious lung nodules and a lesion in the proximal left femur reported as an osteoid osteoma. Wholebody PET-CT scans were performed on a Siemens LSO Biograph, 60mins after the injection of 350Mbq of Fl 8-Fag, with arms at the patient's side and head in the field-of-view. On both occasions the patient had to pay for the scan. On the 2004 PET-CT scan, the CT brain revealed multiple hyperdense lesions consistent with hemorrhagic metastases. In addition, there were innumerable glucose avid foci involving viscera, nodes and skeleton consistent with disseminated disease. Our case illustrates: (i) the value of PET in the management of metastatic breast cancer; (ii) the improved accuracy of PET-CT in delineating sites of disease; (iii) the issues of head movement in PET-CT and. (iv) the problem with lack of

  11. CT after gastrectomy for gastric carcinoma : significance of soft tissue surrounding the celiac axis

    International Nuclear Information System (INIS)

    Baek, Seung Yon; Kim, Hae Young; Choi, Hye Young; Lee, Sun Wha; Ko, Eun Joo; Lee, Myung Sook

    1997-01-01

    To evaluate whether soft tissue surrounding the celiac axis, as seen on abdominal CT imaging after gastrectomy for gastric carcinoma, should be considered as the recurrence of carcinoma or postoperative change. One hundred and forty-one abdominal CT examinations of 71 patients who had undergone subtotal or total gastrectomy for gastric carcinoma were included in our study. Conventional CT scans were obtained with 1cm thickness and interval from the diaphragm to the kidneys after contrast enhancement. It was considered that carcinoma had not recurred if findings were negative on UGI series, endoscopy with biopsy and a normal level of carcinoembryonic antigen except for soft tissue surrounding the celiac axis on abdominal CT. We then divided subjects into a recurrence group(N=20) and normal group(N=51) and on initial follow-up CT(FU-CT), analyzed the incidence, margin, shape, extent, degree and pattern of attenuation of the soft tissue surrounding the celiac axis in both groups. Since the second FU-CT examination, we observed changes in the soft tissue surrounding the celiac axis. On initial follow-up CT, at mean 308 days after surgery, fifty-five percent(39/71) of total patients (70%(14/20) of the recurrence group and 49%(25/51) of the normal group) showed soft tissue surrounding the celiac axis. The margin was distinct in 12(86%) of the recurrence group and indistinct in 21(84%) of the normal group(p<0.001). Twelve (86%) of the recurrence group showed a nodular or confluent nodular shape and 21(84%) of the normal group showed a permeative shape (p<0.001). Extent was unilateral in eight (57%) of the recurrence group and bilateral in 16(64%) of the normal group. Attenuation was similar to that of the spleen and muscle in seven(50%) of the recurrence group and was similar to that of muscle in 18(72%) of the normal group. The pattern of attenuation was homogeneous in 13(93%) of the recurrence group and 21(84%) of the normal group. There was no significant difference in

  12. CT evaluation of primary epiphyseal bone abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Azouz, E.M. (Dept. of Radiology, McGill Univ., Montreal Children' s Hospital, PQ (Canada)); Greenspan, A. (Dept. of Radiology, California Univ., Davis School of Medicine, Sacramento, CA (United States)); Marton, D. (Dept. of Radiology, Montreal Univ., Hopital Ste Justine, PQ (Canada))

    1993-01-01

    We reviewed the clinical, radiographic, and computed tomographic (CT) findings in eight children with a histologically proven diagnosis of epiphyseal or apophyseal osteomyelitis. In all cases the femur was involved: in five the osteomyelitis was localized in the femoral condyle, in two it was in the greater trochanter, and in one it was in the femoral head epiphysis. In four of the six cases of epiphyseal involvement there was associated joint effusion or septic arthritis. CT examination may demonstrate a serpentine tract, a sequestrum, cortical destruction or adjacent soft tissue swelling and can differentiate osteomyelitis from other epiphyseal lucent lesions, particularly chondroblastoma and osteoid osteoma. Early diagnosis helps avoid delays in initiating antibiotic or surgical treatment caused by the unusual (epiphyseal or apophyseal) location of the bone abscess. (orig./GD)

  13. Feasibility of epicardial adipose tissue quantification in non-ECG-gated low-radiation-dose CT: comparison with prospectively ECG-gated cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Simon-Yarza, Isabel; Viteri-Ramirez, Guillermo; Saiz-Mendiguren, Ramon; Slon-Roblero, Pedro J.; Paramo, Maria [Dept. of Radiology, Clinica Univ. de Navarra, Pamplona (Spain); Bastarrika, Gorka [Dept. of Radiology, Clinica Univ. de Navarra, Pamplona (Spain); Cardiac Imaging Unit, Clinica Univ. de Navarra, Pamplona (Spain)], e-mail: bastarrika@unav.es

    2012-06-15

    Background: Epicardial adipose tissue (EAT) is an important indicator of cardiovascular risk. This parameter is generally assessed on ECG-gated computed tomography (CT) images. Purpose: To evaluate feasibility and reliability of EAT quantification on non-gated thoracic low-radiation-dose CT examinations with respect to prospectively ECG-gated cardiac CT acquisition. Material and Methods: Sixty consecutive asymptomatic smokers (47 men; mean age 64 {+-} 9.8 years) underwent low-dose CT of the chest and prospectively ECG-gated cardiac CT acquisitions (64-slice dual-source CT). The two examinations were reconstructed with the same range, field of view, slice thickness, and convolution algorithm. Two independent observers blindly quantified EAT volume using commercially available software. Data were compared with paired sample Student t-test, concordance correlation coefficients (CCC), and Bland-Altman plots. Results: No statistically significant difference was observed for EAT volume quantification with low-dose-CT (141.7 {+-} 58.3 mL) with respect to ECG-gated CT (142.7 {+-} 57.9 mL). Estimation of CCC showed almost perfect concordance between the two techniques for EAT-volume assessment (CCC, 0.99; mean difference, 0.98 {+-} 5.1 mL). Inter-observer agreement for EAT volume estimation was CCC: 0.96 for low-dose-CT examinations and 0.95 for ECG-gated CT. Conclusion: Non-gated low-dose CT allows quantifying EAT with almost the same concordance and reliability as using dedicated prospectively ECG-gated cardiac CT acquisition protocols.

  14. Feasibility of epicardial adipose tissue quantification in non-ECG-gated low-radiation-dose CT: comparison with prospectively ECG-gated cardiac CT

    International Nuclear Information System (INIS)

    Simon-Yarza, Isabel; Viteri-Ramirez, Guillermo; Saiz-Mendiguren, Ramon; Slon-Roblero, Pedro J.; Paramo, Maria; Bastarrika, Gorka

    2012-01-01

    Background: Epicardial adipose tissue (EAT) is an important indicator of cardiovascular risk. This parameter is generally assessed on ECG-gated computed tomography (CT) images. Purpose: To evaluate feasibility and reliability of EAT quantification on non-gated thoracic low-radiation-dose CT examinations with respect to prospectively ECG-gated cardiac CT acquisition. Material and Methods: Sixty consecutive asymptomatic smokers (47 men; mean age 64 ± 9.8 years) underwent low-dose CT of the chest and prospectively ECG-gated cardiac CT acquisitions (64-slice dual-source CT). The two examinations were reconstructed with the same range, field of view, slice thickness, and convolution algorithm. Two independent observers blindly quantified EAT volume using commercially available software. Data were compared with paired sample Student t-test, concordance correlation coefficients (CCC), and Bland-Altman plots. Results: No statistically significant difference was observed for EAT volume quantification with low-dose-CT (141.7 ± 58.3 mL) with respect to ECG-gated CT (142.7 ± 57.9 mL). Estimation of CCC showed almost perfect concordance between the two techniques for EAT-volume assessment (CCC, 0.99; mean difference, 0.98 ± 5.1 mL). Inter-observer agreement for EAT volume estimation was CCC: 0.96 for low-dose-CT examinations and 0.95 for ECG-gated CT. Conclusion: Non-gated low-dose CT allows quantifying EAT with almost the same concordance and reliability as using dedicated prospectively ECG-gated cardiac CT acquisition protocols

  15. The influence of patient positioning in breast CT on breast tissue coverage and patient comfort

    Energy Technology Data Exchange (ETDEWEB)

    Roessler, A.C.; Althoff, F.; Kalender, W. [Erlangen Univ. (Germany). Inst. of Medical Physics; Wenkel, E. [University Hospital of Erlangen (Germany). Radiological Inst.

    2015-02-15

    The presented study aimed at optimizing a patient table design for breast CT (BCT) systems with respect to breast tissue coverage and patient comfort. Additionally, the benefits and acceptance of an immobilization device for BCT using underpressure were evaluated. Three different study parts were carried out. In a positioning study women were investigated on an MRI tabletop with exchangeable inserts (flat and cone-shaped with different opening diameters) to evaluate their influence on breast coverage and patient comfort in various positioning alternatives. Breast length and volume were calculated to compare positioning modalities including various opening diameters and forms. In the second study part, an underpressure system was tested for its functionality and comfort on a stereotactic biopsy table mimicking a future CT scanner table. In the last study part, this system was tested regarding breast tissue coverage. Best results for breast tissue coverage were shown for cone-shaped table inserts with an opening of 180 mm. Flat inserts did not provide complete coverage of breast tissue. The underpressure system showed robust function and tended to pull more breast tissue into the field of view. Patient comfort was rated good for all table inserts, with highest ratings for cone-shaped inserts. Cone-shaped tabletops appeared to be adequate for BCT systems and to allow imaging of almost the complete breast. An underpressure system proved promising for the fixation of the breast during imaging and increased coverage. Patient comfort appears to be adequate.

  16. Evaluation of diffuse thyroid diseases and thyroid nodules by CT

    International Nuclear Information System (INIS)

    Okamoto, Kyoko; Imanishi, Yoshimasa; Nakaji, Shunsuke; Shinagawa, Toshihito

    2007-01-01

    Imanishi et al. have previously reported that the changes in CT values reveal not only the change in iodine concentration in thyroid follicles, but also represent secondary changes in follicular content and follicular cells and/or interstitial structures. Thus, we performed thyroid CT without contrast material in 138 controls, 417 cases with diffuse thyroid diseases, and 279 cases with thyroid nodules, and evaluated the CT images based on the relation between the change in CT values and pathological changes. In 89% of the controls and 43% of patients with diffuse thyroid diseases, the thyroid CT revealed diffuse high density. In contrast, the 94% of thyroids that demonstrated diffuse low density were from patients with diffuse thyroid diseases. Eighty-four percent of malignant nodules and 64% of benign nodules had inhomogeneous densities, and only 26% of benign thyroid nodules had homogeneous density. However, 71% of nodules that showed high and low densities with regular and clear borders, and 82% of nodules that showed papillary proliferation in a cyst pattern were benign. Although only 58% of nodules with calcification were malignant, 66% of nodules with calcification in the central portion, and 86% of nodules with calcification of a disseminated and convergent pattern in distribution were malignant. Sixty-two percent of thyroids that surrounded nodules had chronic thyroiditis, hypoplasia and/or adenomatous goiter. Thus, unclear borders between a nodule and the surrounding thyroid tissue did not increase the possibility of malignancy. However, the unclear and/or lobulated border between a nodule and extra thyroid tissue increased the possibility of malignancy. We concluded that thyroid CT without contrast material is useful for the diagnosis of thyroid diseases. (author)

  17. CT measurement of breast glandular tissue and its association with testicular cancer

    Energy Technology Data Exchange (ETDEWEB)

    Klang, Eyal [Tel Aviv University, Department of Radiology, Chaim Sheba Medical Center, Tel Aviv (Israel); The Chaim Sheba Medical Center, Tel Hashomer (Israel); Rozendorn, Noa; Raskin, Steve; Portnoy, Orith; Sklair, Miri; Marom, Edith M.; Konen, Eli; Amitai, Michal M. [Tel Aviv University, Department of Radiology, Chaim Sheba Medical Center, Tel Aviv (Israel)

    2017-02-15

    To evaluate the associations between breast glandular tissues diameters as determined by CT and b-hCG levels, histological types, tumour spread and prognosis in patients with testicular germ cell tumour. Ninety-four patients with pre-treatment CT scan and markers (b-hCG, AFP, LDH) were retrospectively collected. A radiologist measured diameters in all CT examinations and correlation between diameters and log (b-hCG) was assessed (Pearson's coefficient). The ability of measured diameters to predict lymphatic and distant haematogenous metastatic spread was evaluated (ROC curves). The associations between measured diameter cut-off values of 20 and 25 mm and International Germ Cell Cancer Collaborative Group (IGCCCG) classification, lymphatic and distant haematogenous metastatic spread and histological subtypes were evaluated (chi squared test). Breast glandular diameters correlated to log(b-hCG) (r = 0.579) and predicted distant haematogenous metastatic spread (AUC = 0.78). Worse prognosis (intermediate or poor IGCCCG) was shown for 20 mm (27.3 vs. 4.2 %, p = 0.005) and 25 mm (33.3 vs. 6.1 %, p = 0.014). A diameter of 25 mm was associated with non-seminoma (91.7 vs. 48.8 %, p = 0.005). Breast glandular tissue diameters correlated with log(b-hCG) and predicted distant haematogenous metastases. Twenty and 25 mm were associated with worse prognosis and 25 mm was able to distinguish between seminoma and non-seminoma. (orig.)

  18. Tracheal CT morphology: correlation with distribution and extent of thoracic adipose tissue

    Energy Technology Data Exchange (ETDEWEB)

    Ap Dafydd, Derfel [Imperial College Healthcare NHS Trust, Department of Radiology, Charing Cross Hospital, London (United Kingdom); Desai, Sujal R. [King' s College Hospital NHS Foundation Trust, King' s College London, King' s Health Partners, London (United Kingdom); Gordon, Fabiana; Copley, Susan J. [Imperial College, London (United Kingdom)

    2016-10-15

    To evaluate the relationship between adipose tissue measurements and anterior bowing of the posterior tracheal wall in a large nonselected group of patients undergoing CT pulmonary angiography (CTPA). Consecutive patients undergoing CTPA over a 4-month period were analyzed retrospectively. Using an adapted scoring system (posterior bowing, flattening, mild/moderate or severe anterior bowing of the posterior tracheal membrane), the axial morphology and cross-sectional area of the trachea at the narrowest point and 1 cm above the aortic arch were evaluated. Measurements of adipose tissue were taken (anterior mediastinal fat width, sagittal upper abdominal diameter and subcutaneous fat thickness at the level of the costophrenic angle). Relationships between tracheal morphology and measurements of adipose tissue were analyzed. 296 patients were included (120 males, 176 females, mean age 59 years, range 19-90). Severe anterior bowing of the posterior tracheal wall correlated with increasing sagittal upper abdominal diameter (p = 0.002). Mild/moderate and severe anterior bowing of the posterior tracheal wall correlated with increasing mediastinal fat width (p = 0.000 and p = 0.031, respectively). Tracheal cross-sectional area was inversely correlated with increasing subcutaneous fat thickness (p = 0.022). The findings demonstrate a statistically significant relationship between CT tracheal morphology and adipose tissue measurements in a large nonselected population. (orig.)

  19. Use of the CT component of PET-CT to improve PET-MR registration: demonstration in soft-tissue sarcoma

    International Nuclear Information System (INIS)

    Somer, Edward J; Benatar, Nigel A; O'Doherty, Michael J; Smith, Mike A; Marsden, Paul K

    2007-01-01

    We have investigated improvements to PET-MR image registration offered by PET-CT scanning. Ten subjects with suspected soft-tissue sarcomas were scanned with an in-line PET-CT and a clinical MR scanner. PET to CT, CT to MR and PET to MR image registrations were performed using a rigid-body external marker technique and rigid and non-rigid voxel-similarity algorithms. PET-MR registration was also performed using transformations derived from the registration of CT to MR. The external marker technique gave fiducial registration errors of 2.1 mm, 5.1 mm and 5.3 mm for PET-CT, PET-MR and CT-MR registration. Target registration errors were 3.9 mm, 9.0 mm and 9.3 mm, respectively. Voxel-based algorithms were evaluated by measuring the distance between corresponding fiducials after registration. Registration errors of 6.4 mm, 14.5 mm and 9.5 mm, respectively, for PET-CT, PET-MR and CT-MR were observed for rigid-body registration while non-rigid registration gave errors of 6.8 mm, 16.3 mm and 7.6 mm for the same modality combinations. The application of rigid and non-rigid CT to MR transformations to accompanying PET data gives significantly reduced PET-MR errors of 10.0 mm and 8.5 mm, respectively. Visual comparison by two independent observers confirmed the improvement over direct PET-MR registration. We conclude that PET-MR registration can be more accurately and reliably achieved using the hybrid technique described than through direct rigid-body registration of PET to MR

  20. The effect of iodine uptake on radiation dose absorbed by patient tissues in contrast enhanced CT imaging. Implications for CT dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Perisinakis, Kostas; Damilakis, John [University of Crete, Department of Medical Physics, Medical School, Heraklion, Crete (Greece); University Hospital of Heraklion, Department of Medical Physics, Heraklion, Crete (Greece); Tzedakis, Antonis; Papadakis, Antonios E. [University Hospital of Heraklion, Department of Medical Physics, Heraklion, Crete (Greece); Spanakis, Kostas [University Hospital of Heraklion, Department of Radiology, Heraklion, Crete (Greece); Hatzidakis, Adam [University Hospital of Heraklion, Department of Radiology, Heraklion, Crete (Greece); University of Crete, Department of Radiology, Medical School, Heraklion, Crete (Greece)

    2018-01-15

    To investigate the effect of iodine uptake on tissue/organ absorbed doses from CT exposure and its implications in CT dosimetry. The contrast-induced CT number increase of several radiosensitive tissues was retrospectively determined in 120 CT examinations involving both non-enhanced and contrast-enhanced CT imaging. CT images of a phantom containing aqueous solutions of varying iodine concentration were obtained. Plots of the CT number increase against iodine concentration were produced. The clinically occurring iodine tissue uptake was quantified by attributing recorded CT number increase to a certain concentration of aqueous iodine solution. Clinically occurring iodine uptake was represented in mathematical anthropomorphic phantoms. Standard 120 kV CT exposures were simulated using Monte Carlo methods and resulting organ doses were derived for non-enhanced and iodine contrast-enhanced CT imaging. The mean iodine uptake range during contrast-enhanced CT imaging was found to be 0.02-0.46% w/w for the investigated tissues, while the maximum value recorded was 0.82% w/w. For the same CT exposure, iodinated tissues were found to receive higher radiation dose than non-iodinated tissues, with dose increase exceeding 100% for tissues with high iodine uptake. Administration of iodinated contrast medium considerably increases radiation dose to tissues from CT exposure. (orig.)

  1. Evaluation of registration methods on thoracic CT

    DEFF Research Database (Denmark)

    Murphy, K.; van Ginneken, B.; Reinhardt, J.

    2011-01-01

    method and the evaluation is independent, using the same criteria for all participants. All results are published on the EMPIRE10 website (http://empire10.isi.uu.nl). The challenge remains ongoing and open to new participants. Full results from 24 algorithms have been published at the time of writing......EMPIRE10 (Evaluation of Methods for Pulmonary Image REgistration 2010) is a public platform for fair and meaningful comparison of registration algorithms which are applied to a database of intra-patient thoracic CT image pairs. Evaluation of non-rigid registration techniques is a non trivial task....... This article details the organisation of the challenge, the data and evaluation methods and the outcome of the initial launch with 20 algorithms. The gain in knowledge and future work are discussed....

  2. Extramedullary paraspinal hematopoiesis in thalassemia: CT and MRI evaluation

    International Nuclear Information System (INIS)

    Tsitouridis, J.; Stamos, S.; Hassapopoulou, E.; Tsitouridis, K.; Nikolopoulos, P.

    1999-01-01

    We present a comparative CT and MRI study of the paraspinal extramedullary hematopoiesis in 32 thalassemic patients. The patients were classified into four groups according to the MRI and CT imaging findings. Active recent extramedullary paraspinal hematopoietic masses show soft tissue behavior in both CT and MRI. Older inactive masses reveal iron deposition or fatty replacement. Combined imaging findings of paraspinal extramedullary hematopoiesis revealed the phase of its evolution and the correct diagnosis

  3. Extramedullary paraspinal hematopoiesis in thalassemia: CT and MRI evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Tsitouridis, J.; Stamos, S.; Hassapopoulou, E.; Tsitouridis, K.; Nikolopoulos, P

    1999-04-01

    We present a comparative CT and MRI study of the paraspinal extramedullary hematopoiesis in 32 thalassemic patients. The patients were classified into four groups according to the MRI and CT imaging findings. Active recent extramedullary paraspinal hematopoietic masses show soft tissue behavior in both CT and MRI. Older inactive masses reveal iron deposition or fatty replacement. Combined imaging findings of paraspinal extramedullary hematopoiesis revealed the phase of its evolution and the correct diagnosis.

  4. Classification of fibroglandular tissue distribution in the breast based on radiotherapy planning CT

    International Nuclear Information System (INIS)

    Juneja, Prabhjot; Evans, Philip; Windridge, David; Harris, Emma

    2016-01-01

    Accurate segmentation of breast tissues is required for a number of applications such as model based deformable registration in breast radiotherapy. The accuracy of breast tissue segmentation is affected by the spatial distribution (or pattern) of fibroglandular tissue (FT). The goal of this study was to develop and evaluate texture features, determined from planning computed tomography (CT) data, to classify the spatial distribution of FT in the breast. Planning CT data of 23 patients were evaluated in this study. Texture features were derived from the radial glandular fraction (RGF), which described the distribution of FT within three breast regions (posterior, middle, and anterior). Using visual assessment, experts grouped patients according to FT spatial distribution: sparse or non-sparse. Differences in the features between the two groups were investigated using the Wilcoxon rank test. Classification performance of the features was evaluated for a range of support vector machine (SVM) classifiers. Experts found eight patients and 15 patients had sparse and non-sparse spatial distribution of FT, respectively. A large proportion of features (>9 of 13) from the individual breast regions had significant differences (p <0.05) between the sparse and non-sparse group. The features from middle region had most significant differences and gave the highest classification accuracy for all the SVM kernels investigated. Overall, the features from middle breast region achieved highest accuracy (91 %) with the linear SVM kernel. This study found that features based on radial glandular fraction provide a means for discriminating between fibroglandular tissue distributions and could achieve a classification accuracy of 91 %

  5. Recurrent postoperative sciatica: Evaluation with MR imaging and enhanced CT

    International Nuclear Information System (INIS)

    Duoauferrier, R.; Frocrain, L.; Husson, J.L.

    1987-01-01

    The authors prospectively compared surface coil MR (SCMR) imaging and CT with iodinate contrast enhancement in 50 patients with recurrent postoperative sciatica. Of the 50 patients enrolled in the study, surgical treatment was elected in 27 patients after independent examination of SCMR imaging and enhanced CT. All predictions made with the 27 SCMR images were surgically confirmed. The surgical findings were 20 recurrent disk herniations, five recurrent disk herniations with scar tissue, one disk herniation above the level of diskectomy, and one disk herniation below the level of diskectomy. The surgical findings of the 12 patients who had scar tissue on CT were seven recurrent disk herniations, four recurrent disk herniations with scar tissue, and one disk herniation below the operated level. SCMR imaging was more sensitive and more specific than CT to differentiate scar tissue from recurrent disk herniation

  6. Accuracy and role of contrast-enhanced CT in diagnosis and surgical planning in 88 soft tissue tumours of extremities

    International Nuclear Information System (INIS)

    Verga, Lucia; Robiati, Sara; De Marchi, Armanda; Martorano, Domenico; Faletti, Carlo; Brach del Prever, Elena Maria; Linari, Alessandra; Boffano, Michele; Piana, Raimondo

    2016-01-01

    Soft tissue tumours (STT) require accurate diagnosis in order to identify potential malignancies. Preoperative planning is fundamental to avoid inadequate treatments. The role of contrast-enhanced computed tomography (CT) for local staging remains incompletely assessed. Aims of the study were to evaluate CT accuracy in discriminating active from aggressive tumours compared to histology and evaluate the role of CT angiography (CTA) in surgical planning. This retrospective cohort series of 88 cases from 1200 patients (7 %) was locally studied by contrast-enhanced CT and CTA in a referral centre: 74 malignant tumours, 14 benign lesions. Contrast-enhancement patterns and relationship of the mass with major vessels and bone were compared with histology on surgically excised samples. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) were evaluated in discriminating active from aggressive tumours. Sensitivity in differentiating aggressive tumours from active lesions was 89 %, specificity 84 %, PPV 90 %, NPV 82 %. The relationship between mass and major vessels/bone was fundamental for surgical strategy respectively in 40 % and in 58 % of malignant tumours. Contrast-enhanced CT and CTA are effective in differentiating aggressive masses from active lesions in soft tissue and in depicting the relationship between tumour and adjacent bones and major vessels. (orig.)

  7. 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

  8. 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.

  9. The diagnosis of MR and CT scan for myofascitis of connective tissue disease: comparison with biopsy examination

    International Nuclear Information System (INIS)

    Xu Jianrong; Zhou Yan; Chai Weimin; Yao Qiuying; Li Lei; Li Lan; Li Zhengyang

    2002-01-01

    Objective: To evaluate the utility of MRI, CT and biopsy examinations in detecting myofascitis lesions of connective tissue disease. Methods: The study group consisted of 22 patients proven by clinical features and laboratory examination, including 8 cases of dermatomyositis (DM), 12 cases of polymyositis (PM), and 2 cases of eosinophilic fascitis. All patients received CT scan, SE-T 1 WI, SE-T 2 WI, SPIR, and CT guiding biopsy at the thigh region. Results: Biopsy detected muscular diseases in 17 cases and fascitis in 5 cases. MRI detected muscular diseases in 14 and fascitis in 9. CT detected muscular diseases in 5 and fascitis in 9. Myositis, amyotrophy, and fascitis may be alone or united in one case. Myositis (9 cases) appeared as low signal on T 1 WI and high signal on T 2 WI or SPIR. Amyotrophy (9 cases) presented hyperintensity on both T 1 WI and T 2 WI. SPIR was more sensitive in detecting myositis than CT and T 1 WI, P < 0.05. Myositis was more frequent in cases with DM(6/8) than in cases with PM (3/12), P < 0.05. Also, myositis was more frequently encountered in active phase (7/11) than in quiescent phase (2/11). Conclusion: MRI and CT appear to be valuable in quantitatively and qualitatively estimating myofascitis of connective tissue diseases

  10. Simulation evaluation of quantitative myocardial perfusion assessment from cardiac CT

    Science.gov (United States)

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

    2014-03-01

    Contrast enhancement on cardiac CT provides valuable information about myocardial perfusion and methods have been proposed to assess perfusion with static and dynamic acquisitions. There is a lack of knowledge and consensus on the appropriate approach to ensure 1) sufficient diagnostic accuracy for clinical decisions and 2) low radiation doses for patient safety. This work developed a thorough dynamic CT simulation and several accepted blood flow estimation techniques to evaluate the performance of perfusion assessment across a range of acquisition and estimation scenarios. Cardiac CT acquisitions were simulated for a range of flow states (Flow = 0.5, 1, 2, 3 ml/g/min, cardiac output = 3,5,8 L/min). CT acquisitions were simulated with a validated CT simulator incorporating polyenergetic data acquisition and realistic x-ray flux levels for dynamic acquisitions with a range of scenarios including 1, 2, 3 sec sampling for 30 sec with 25, 70, 140 mAs. Images were generated using conventional image reconstruction with additional image-based beam hardening correction to account for iodine content. Time attenuation curves were extracted for multiple regions around the myocardium and used to estimate flow. In total, 2,700 independent realizations of dynamic sequences were generated and multiple MBF estimation methods were applied to each of these. Evaluation of quantitative kinetic modeling yielded blood flow estimates with an root mean square error (RMSE) of ~0.6 ml/g/min averaged across multiple scenarios. Semi-quantitative modeling and qualitative static imaging resulted in significantly more error (RMSE = ~1.2 and ~1.2 ml/min/g respectively). For quantitative methods, dose reduction through reduced temporal sampling or reduced tube current had comparable impact on the MBF estimate fidelity. On average, half dose acquisitions increased the RMSE of estimates by only 18% suggesting that substantial dose reductions can be employed in the context of quantitative myocardial

  11. Subcutaneous Tissue Thickness is an Independent Predictor of Image Noise in Cardiac CT

    International Nuclear Information System (INIS)

    Staniak, Henrique Lane; Sharovsky, Rodolfo; Pereira, Alexandre Costa; Castro, Cláudio Campi de; Benseñor, Isabela M.; Lotufo, Paulo A.; Bittencourt, Márcio Sommer

    2014-01-01

    Few data on the definition of simple robust parameters to predict image noise in cardiac computed tomography (CT) exist. To evaluate the value of a simple measure of subcutaneous tissue as a predictor of image noise in cardiac CT. 86 patients underwent prospective ECG-gated coronary computed tomographic angiography (CTA) and coronary calcium scoring (CAC) with 120 kV and 150 mA. The image quality was objectively measured by the image noise in the aorta in the cardiac CTA, and low noise was defined as noise < 30HU. The chest anteroposterior diameter and lateral width, the image noise in the aorta and the skin-sternum (SS) thickness were measured as predictors of cardiac CTA noise. The association of the predictors and image noise was performed by using Pearson correlation. The mean radiation dose was 3.5 ± 1.5 mSv. The mean image noise in CT was 36.3 ± 8.5 HU, and the mean image noise in non-contrast scan was 17.7 ± 4.4 HU. All predictors were independently associated with cardiac CTA noise. The best predictors were SS thickness, with a correlation of 0.70 (p < 0.001), and noise in the non-contrast images, with a correlation of 0.73 (p < 0.001). When evaluating the ability to predict low image noise, the areas under the ROC curve for the non-contrast noise and for the SS thickness were 0.837 and 0.864, respectively. Both SS thickness and CAC noise are simple accurate predictors of cardiac CTA image noise. Those parameters can be incorporated in standard CT protocols to adequately adjust radiation exposure

  12. Subcutaneous Tissue Thickness is an Independent Predictor of Image Noise in Cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Staniak, Henrique Lane; Sharovsky, Rodolfo [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil); Pereira, Alexandre Costa [Hospital das Clínicas - Universidade de São Paulo, São Paulo, SP (Brazil); Castro, Cláudio Campi de; Benseñor, Isabela M.; Lotufo, Paulo A. [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil); Faculdade de Medicina - Universidade de São Paulo, São Paulo, SP (Brazil); Bittencourt, Márcio Sommer, E-mail: msbittencourt@mail.harvard.edu [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil)

    2014-01-15

    Few data on the definition of simple robust parameters to predict image noise in cardiac computed tomography (CT) exist. To evaluate the value of a simple measure of subcutaneous tissue as a predictor of image noise in cardiac CT. 86 patients underwent prospective ECG-gated coronary computed tomographic angiography (CTA) and coronary calcium scoring (CAC) with 120 kV and 150 mA. The image quality was objectively measured by the image noise in the aorta in the cardiac CTA, and low noise was defined as noise < 30HU. The chest anteroposterior diameter and lateral width, the image noise in the aorta and the skin-sternum (SS) thickness were measured as predictors of cardiac CTA noise. The association of the predictors and image noise was performed by using Pearson correlation. The mean radiation dose was 3.5 ± 1.5 mSv. The mean image noise in CT was 36.3 ± 8.5 HU, and the mean image noise in non-contrast scan was 17.7 ± 4.4 HU. All predictors were independently associated with cardiac CTA noise. The best predictors were SS thickness, with a correlation of 0.70 (p < 0.001), and noise in the non-contrast images, with a correlation of 0.73 (p < 0.001). When evaluating the ability to predict low image noise, the areas under the ROC curve for the non-contrast noise and for the SS thickness were 0.837 and 0.864, respectively. Both SS thickness and CAC noise are simple accurate predictors of cardiac CTA image noise. Those parameters can be incorporated in standard CT protocols to adequately adjust radiation exposure.

  13. Evaluation of the reconstruction of image acquired from CT simulator to reduce metal artifact

    International Nuclear Information System (INIS)

    Choi, Ji Hun; Park, Jin Hong; Choi, Byung Don; Won, Hui Su; Chang, Nam Jun; Goo, Jang Hyun; Hong, Joo Wan

    2014-01-01

    This study presents the usefulness assessment of metal artifact reduction for orthopedic implants(O-MAR) to decrease metal artifacts from materials with high density when acquired CT images. By CT simulator, original CT images were acquired from Gammex and Rando phantom and those phantoms inserted with high density materials were scanned for other CT images with metal artifacts and then O-MAR was applied to those images, respectively. To evaluate CT images using Gammex phantom, 5 regions of interest(ROIs) were placed at 5 organs and 3 ROIs were set up at points affected by artifacts. The averages of standard deviation(SD) and CT numbers were compared with a plan using original image. For assessment of variations in dose of tissue around materials with high density, the volume of a cylindrical shape was designed at 3 places in images acquired from Rando phantom by Eclipse. With 6 MV, 7-fields, 15x15cm 2 and 100 cGy per fraction, treatment planning was created and the mean dose were compared with a plan using original image. In the test with the Gammex phantom, CT numbers had a few difference at established points and especially 3 points affected by artifacts had most of the same figures. In the case of O-MAR image, the more reduction in SD appeared at all of 8 points than non O-MAR image. In the test using the Rando Phantom, the variations in dose of tissue around high density materials had a few difference between original CT image and CT image with O-MAR. The CT images using O-MAR were acquired clearly at the boundary of tissue around high density materials and applying O-MAR was useful for correcting CT numbers

  14. Comparison of MRI and PET-CT in detecting the loco-regional recurrence of soft tissue sarcomas during surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sun-Young [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Hallym University Sacred Heart Hospital, Department of Radiology, Anyang-si, Gyeonggi-do (Korea, Republic of); Chung, Hye Won [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Chae, Sun Young [University of Ulsan College of Medicine, Asan Medical Center, Department of Nuclear Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Lee, Jong-Seok [University of Ulsan College of Medicine, Asan Medical Center, Department of Orthopedic Surgery, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of)

    2016-10-15

    To investigate the diagnostic performance of MRI and PET-CT for the detection of loco-regional recurrences after soft tissue sarcoma (STS) excision. From Dec 2003 to Aug 2014, 394 patients with STSs, who were included in the electronic patient registry for initial or repeated surgery at our hospital, were retrospectively reviewed. We identified 152 patients who underwent regular postoperative follow-ups with both MRI and PET-CT, obtained within a 3 month period of each other. We analyzed differences in the performance of MRI and PET-CT for the diagnosis of loco-regional recurrences using McNemar's test. The receiver-operating characteristic curves and calculations of the area under the curve were used. Twenty patients were found to have a loco-regional recurrence after tumor excision. For MRI and PET-CT, the sensitivities were 90.0 and 95.0 %, and the specificities 97.7 and 95.5 %, respectively, with positive predictive values of 85.7 and 76.0 % and negative predictive values of 98.5 and 99.2 %, respectively. No significant difference was detected between the sensitivities of MRI and PET-CT (p = 0.125). The area under the receiver-operating characteristic curve for PET-CT (0.952) was not significantly greater than that for MRI (0.939; p = 0.6). MRI of the area of interest is recommended for evaluation of tumor recurrence after surgical excision of STS. PET-CT was shown to be effective for detection of STS recurrence, and comparable to MRI. However, if PET-CT or MRI findings are inconclusive, the other modality may be helpful in differentiating tumor recurrence from post-therapeutic tissue change. (orig.)

  15. CT SCAN EVALUATION OF PULMONARY NODULE

    Directory of Open Access Journals (Sweden)

    A. Ravi Kumar

    2016-06-01

    Full Text Available BACKGROUND Lung carcinomas are quite commonly diagnosed. Thanks to the ever increasing smokers’ population. Majority of the city dwellers are at a higher risk of having this disease when compared to the village counterparts. The stigma through which the person and the family have to undergo before confirming the diagnosis is enormous. So the radiographic methods of diagnosing the malignancies have to improve. Before confirming the diagnosis, the radiologists, the treating physicians should be somewhat confident about the diagnosis so as to prepare the patients and their relatives for the most probable diagnosis before the confirmatory report. The confirmatory procedures include the PET scan and the Histopathology. Both are time consuming procedures and in an economy like ours, finding a PET scanning centre is rather difficult. So the most probable diagnosis has to be thought of using minimal resource. This study puts in a sincere effort to understand and evaluate the pulmonary nodule when identified by a CT scan. This paper is intended to help the practicing radiologists and also make life easy for a practicing physician to identify correctly the lesions and also help the patients to prevent further progression of the disease. METHODS The study was a cross-sectional study. The sample size of the study consisted of thirty patients. CT scan was done in thirty patients who were identified to have lung nodules either by other mode of radiological studies or first time identified in a CT scan itself. The study was conducted in Fathima Institute of Medical Sciences, Kadapa. The study was conducted from 2014 to 2015. RESULT Non-solid nodules were more in number when compared to the solid nodules. All the non-solid nodules were confirmed to be adenomas. Eighty percent of the nodules which were more than 8 mm in size were confirmed to be malignant. One hundred percent of the spiculated border on CT was confirmed to be malignant. In the present study

  16. 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.

  17. 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.

  18. Correlation between CT numbers and tissue parameters needed for Monte Carlo simulations of clinical dose distributions

    Science.gov (United States)

    Schneider, Wilfried; Bortfeld, Thomas; Schlegel, Wolfgang

    2000-02-01

    We describe a new method to convert CT numbers into mass density and elemental weights of tissues required as input for dose calculations with Monte Carlo codes such as EGS4. As a first step, we calculate the CT numbers for 71 human tissues. To reduce the effort for the necessary fits of the CT numbers to mass density and elemental weights, we establish four sections on the CT number scale, each confined by selected tissues. Within each section, the mass density and elemental weights of the selected tissues are interpolated. For this purpose, functional relationships between the CT number and each of the tissue parameters, valid for media which are composed of only two components in varying proportions, are derived. Compared with conventional data fits, no loss of accuracy is accepted when using the interpolation functions. Assuming plausible values for the deviations of calculated and measured CT numbers, the mass density can be determined with an accuracy better than 0.04 g cm-3 . The weights of phosphorus and calcium can be determined with maximum uncertainties of 1 or 2.3 percentage points (pp) respectively. Similar values can be achieved for hydrogen (0.8 pp) and nitrogen (3 pp). For carbon and oxygen weights, errors up to 14 pp can occur. The influence of the elemental weights on the results of Monte Carlo dose calculations is investigated and discussed.

  19. Fibrous soft tissue tumor of neck and shoulder girdle: MR and CT characteristics

    International Nuclear Information System (INIS)

    Gu Yajia; Peng Weijun; Wang Peihua; Wang Jian

    2005-01-01

    Objective: To evaluate MR and CT imagings of desmoplastic fibroblastoma (DF) and aggressive fibromatosis (AF) in neck and shoulder girdle, and to emphasis upon the MRI findings with pathological correlation. Methods: MR and CT appearances of DFs (4 cases) and AFS (3 cases) confirmed by surgical and pathologic findings were retrospective analysed, which were correlated to the pathologic features. Four cases of DF were male patients, with a median age at 48 years. Two cases of AF were female (20, 29 years respectively), and another AF patient was male (79 years). Results: (1) Four DFs were round mass located in the inter muscle space of neck, and the margins were mostly well-circumscribed. Envelope was seen in one lesion on MRI. On unenhanced CT, the masses showed homogeneous low attenuation (2 cases) or slightly low attenuation with several heterogeneous areas in it (1 cases). Enhancement was not obvious on post-contrast CT images. MRI studies were done in two patients. Signal intensity (SI) on MR was homogeneous and heterogeneous one lesion respectively on unenhanced T 1 -weighted images. Mixed SI as low or high SI nodes within isointense compared with muscle on T 2 -weighted images. No evident enhancing was noted after administration of gadopentetate dimeglumine. (2) All three lesions of aggressive fibromatosis arose from musculoaponeurotic structures. The masses were irregular margin and appeared elongated, which oriented in the direction of the muscle bundle. On unenhanced CT examination, the masses had poorly defined and isodense relative to adjacent musculature (2 cases). On T 1 -weighted images, three masses consisted of poormargination and isointensity relative to adjacent muscle. On T 2 -weighted images, two lesions were heterogeneity of signal, which predominantly slightly high in SI with strip-or node-shape low SI, and one lesion had homogeneous high SI. On post-contrast T 1 -weighted images, all lesions showed marked enhancement, heterogeneity of signal

  20. FDG-PET/CT in the evaluation of anal carcinoma

    International Nuclear Information System (INIS)

    Cotter, Shane E.; Grigsby, Perry W.; Siegel, Barry A.

    2006-01-01

    Purpose: Surgical staging and treatment of anal carcinoma has been replaced by noninvasive staging studies and combined modality therapy. In this study, we compare computed tomography (CT) and physical examination to [ 18 F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) in the staging of carcinoma of the anal canal, with special emphasis on determination of spread to inguinal lymph nodes. Methods and Materials: Between July 2003 and July 2005, 41 consecutive patients with biopsy-proved anal carcinoma underwent a complete staging evaluation including physical examination, CT, and 2-FDG-PET/CT. Patients ranged in age from 30 to 89 years. Nine men were HIV-positive. Treatment was with standard Nigro regimen. Results: [ 18 F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) detected 91% of nonexcised primary tumors, whereas CT visualized 59%. FDG-PET/CT detected abnormal uptake in pelvic nodes of 5 patients with normal pelvic CT scans. FDG-PET/CT detected abnormal nodes in 20% of groins that were normal by CT, and in 23% without abnormality on physical examination. Furthermore, 17% of groins negative by both CT and physical examination showed abnormal uptake on FDG-PET/CT. HIV-positive patients had an increased frequency of PET-positive lymph nodes. Conclusion: [ 18 F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography detects the primary tumor more often than CT. FDG-PET/CT detects substantially more abnormal inguinal lymph nodes than are identified by standard clinical staging with CT and physical examination

  1. CT evaluation of severe renal inflammatory disease in children

    International Nuclear Information System (INIS)

    Montgomery, P.; Kuhn, J.P.; Afshani, E.

    1987-01-01

    We have performed CT scans on 15 children and 2 young adults with severe renal inflammatory disease. Most children with urinary tract infections do not require such evaluation. We have, however, found CT helpful in defining the nature of renal abnormality and in defining the extent of disease in selected patients who either presented as diagnostic dilemmas or who did not respond initially to proper medical treatment. We therefore use CT scanning as our initial examination in such problem patients. (orig.)

  2. Recurrent postoperative sciatica: Evaluation with MR imaging and enhanced CT

    International Nuclear Information System (INIS)

    Duvauferrier, R.; Frocain, L.; Husson, J.L.

    1987-01-01

    The authors prospectively compared MR imaging performed with a surface coil and CT performed with iodinated contrast agent enhancement in 50 patients with recurrent postoperative sciatica. Surgical decision was an objective measure of accuracy. Surgical treatment was selected for 27 patients. All 27 underwent MR imaging. The 15 patients who underwent CT/surgical treatment were included in the 27 indications of SCMR. All predictions based on MR imaging findings were confirmed at surgery. There were 25 recurrent disk herniations, including five with scar tissue, and two disk herniations above or below the level of the diskectomy. In the 12 patients with scar tissue detected on CT there were seven recurrent disk hernitions, four recurrent disk herniations with scar tissue, and one disk herniation below the level of the diskectomy

  3. Spiral CT for evaluation of chest trauma

    International Nuclear Information System (INIS)

    Roehnert, W.; Weise, R.

    1997-01-01

    After implementation of spiral CT in our department, we carried out an analysis for determining anew the value of CT as a modality of chest trauma diagnosis in the emergency department. The retrospective study covers a period of 10 months and all emergency patients with chest trauma exmined by spiral CT. The major lesions of varying seriousness covered by this study are: pneumothorax, hematothorax, pulmonary contusion or laceration, mediastinal hematoma, rupture of a vessel, injury of the heart and pericardium. The various fractures are not included in this study. In many cases, spiral CT within relatively short time yields significant diagnostic findings, frequently saving additional angiography. A rigid diagnostic procedure cannot be formulated. Plain-film chest radiography still remains a diagnostic modality of high value. (Orig.) [de

  4. Congenital cystic masses of the face and neck: CT evaluation

    International Nuclear Information System (INIS)

    Chung, Hae Gyeong; Kim, Hyung Jin; Kim, Jae Hyoung; Hwang, Eui Gee; Jeon, Sea Young; Kim, Sun Young; Chung, Sung Hoon

    1991-01-01

    Recognition of the congenital cystic masses of the face and neck is important because they are usually benign, and can be completely cured by surgical excision. We retrospective analyzed CT scan of 18 surgically proven congenital cystic masses of the face and neck. The cases included 5 thyroglossal duct cysts, 4 cystic hygromas, 5 dermoid cysts, 1 branchial cleft cyst, and 3 fissural cysts of the face. Of five cases of thyroglossal duct cysts, CT showed either a well-marginated, rim enhancing unilocular cystic mass (n=3), or a diffuse but heterogeneous highly enhancing soft tissue mass (n=2). The latter two cases were confirmed later as infected thyroglossal duct cysts. Four cases of cystic hygromas were seen as either an irregularly-marginated (n=3) or a well-marginated (n=1) rim enhancing multiseptated cystic mass with a fluid-fluid level. Five cases of dermoid cysts appeared as well-marginated rim enhancing unilocular ovoid masses. The content of each mass was predominantly fluid in four cases, of which additional solid components were found in two, and interspersed fat globules in one. One case was composed of a homogeneous fatty density. One case of branchial cleft cyst was in the anterior triangle near the left mandibular angle, and appeared as a well-marginated enhancing cystic mass with a thick rim. In this case displacement of the adjacent structures was noted also. All three cases of fissural cysts of the face were seen as a well-marginated, rim enhancing cystic mass, causing a smooth pressure erosion of the adjacent bones. We conclude that CT is useful for the evaluation of the congenital cystic masses of the face and neck, because it can differentiate various forms of the congenital lesions and is able to clearly reveal the relation of the mass to the adjacent structures

  5. Congenital cystic masses of the face and neck: CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hae Gyeong; Kim, Hyung Jin; Kim, Jae Hyoung; Hwang, Eui Gee; Jeon, Sea Young; Kim, Sun Young; Chung, Sung Hoon [Gyeongsang National University, Jinju (Korea, Republic of)

    1991-09-15

    Recognition of the congenital cystic masses of the face and neck is important because they are usually benign, and can be completely cured by surgical excision. We retrospective analyzed CT scan of 18 surgically proven congenital cystic masses of the face and neck. The cases included 5 thyroglossal duct cysts, 4 cystic hygromas, 5 dermoid cysts, 1 branchial cleft cyst, and 3 fissural cysts of the face. Of five cases of thyroglossal duct cysts, CT showed either a well-marginated, rim enhancing unilocular cystic mass (n=3), or a diffuse but heterogeneous highly enhancing soft tissue mass (n=2). The latter two cases were confirmed later as infected thyroglossal duct cysts. Four cases of cystic hygromas were seen as either an irregularly-marginated (n=3) or a well-marginated (n=1) rim enhancing multiseptated cystic mass with a fluid-fluid level. Five cases of dermoid cysts appeared as well-marginated rim enhancing unilocular ovoid masses. The content of each mass was predominantly fluid in four cases, of which additional solid components were found in two, and interspersed fat globules in one. One case was composed of a homogeneous fatty density. One case of branchial cleft cyst was in the anterior triangle near the left mandibular angle, and appeared as a well-marginated enhancing cystic mass with a thick rim. In this case displacement of the adjacent structures was noted also. All three cases of fissural cysts of the face were seen as a well-marginated, rim enhancing cystic mass, causing a smooth pressure erosion of the adjacent bones. We conclude that CT is useful for the evaluation of the congenital cystic masses of the face and neck, because it can differentiate various forms of the congenital lesions and is able to clearly reveal the relation of the mass to the adjacent structures.

  6. Cine CT in the evaluation of coronary bypass graft patency

    International Nuclear Information System (INIS)

    Stanford, W.; Rooholamini, M.; Rumberger, J.; Marcus, M.; Hiratzka, L.

    1986-01-01

    Cine CT produces axial images over an 8-cm section of the aorta in 50 msec. This characteristic makes the technique useful for evaluating coronary bypass graft (CBG) patency. With the use of 40 ml of 67% iothalamate sodium injected via an antecubital vein, 28 patients with 68 CBGs underwent cine CT. Ten patients with 21 CBGs also underwent cardiac catheterization. In the latter group the overall accuracy of cine CT compared to cardiac catheterization was 95.2% (20/21). The sensitivity was 94.1% (16/17), and the specificity was 100% (4/4). This figure compares favorably with the 92% sensitivity achieved with conventional CT

  7. Evaluation of Marfan syndrome: MR imaging versus CT

    International Nuclear Information System (INIS)

    Soulen, R.L.; Fishman, E.K.; Pyeritz, R.E.; Gott, V.L.; Zerhouni, E.A.

    1986-01-01

    Twenty-five patients with Marfan, syndrome underwent both CT and MR imaging. MR imaging were interpreted in blinded fashion and then compared with CT scans MR imaging was found to be equivalent to CT in the detection of aortic, dural, and hip abnormalities in patients not operated on. MR imaging was superior to CT in the evaluation of postoperative patients because the artifact produced by Bjork-Shirley or St. Jude valves precludes adequate evaluation of the aortic root on CT while producing only a small inferior field distortion (a ''pseudo-ventricular septal defect'') on MR imaging. The absence of radiation exposure is another major advantage of MR imaging in this relatively young population requiring serial studies. The authors conclude that MR imaging is the modality of choice for the evaluation and follow-up of patients with Marfan syndrome and offers an appropriate means of screening their kindred

  8. Evaluation of CT findings for diagnosis of pleural effusions

    International Nuclear Information System (INIS)

    Arenas-Jimenez, J.; Alonso-Charterina, S.; Fernandez-Latorre, F.; Gil-Sanchez, S.; Sanchez-Paya, J.; Lloret-Llorens, M.

    2000-01-01

    Computed tomography studies are usually used to assess patients with pleural effusions, and radiologists should be aware of the significance of different CT findings for the diagnosis of the effusion. The purpose of this study was to evaluate CT findings for etiological diagnosis of pleural effusions. Contrast-enhanced CT of the chest of 211 patients with pleural effusion of definite diagnosis were evaluated. The CT images were evaluated for the presence and extent of pleural effusion, thickening or nodules, extrapleural fat and other changes in the mediastinum or lung. The CT scans were read by two independent observers and correlation between them was evaluated. Comparison of CT findings between benign and malignant effusions, between exudates and transudates, and between empyemas and the other parapneumonic effusions were carried out. Kappa values for most CT findings were >0.85. Loculation, pleural thickening, pleural nodules, and extrapleural fat of increased density were only present in exudative effusions. Multiple pleural nodules and nodular pleural thickening were the only pleural findings limited to malignant pleural effusions. The signs were also more frequently seen in empyemas than in other parapneumonic effusions. Computed tomography findings can help to distinguish between transudates and exudates. Although there is some overlap between benign and malignant pleural effusions, pleural nodules and nodular pleural thickening were present almost exclusively in the latter. Although differences between CT findings of empyemas and the other parapneumonic effusions exist, there is no finding which can definitely differentiate between them. (orig.)

  9. SU-E-I-73: Clinical Evaluation of CT Image Reconstructed Using Interior Tomography

    International Nuclear Information System (INIS)

    Zhang, J; Ge, G; Winkler, M; Cong, W; Wang, G

    2014-01-01

    Purpose: Radiation dose reduction has been a long standing challenge in CT imaging of obese patients. Recent advances in interior tomography (reconstruction of an interior region of interest (ROI) from line integrals associated with only paths through the ROI) promise to achieve significant radiation dose reduction without compromising image quality. This study is to investigate the application of this technique in CT imaging through evaluating imaging quality reconstructed from patient data. Methods: Projection data were directly obtained from patients who had CT examinations in a Dual Source CT scanner (DSCT). Two detectors in a DSCT acquired projection data simultaneously. One detector provided projection data for full field of view (FOV, 50 cm) while another detectors provided truncated projection data for a FOV of 26 cm. Full FOV CT images were reconstructed using both filtered back projection and iterative algorithm; while interior tomography algorithm was implemented to reconstruct ROI images. For comparison reason, FBP was also used to reconstruct ROI images. Reconstructed CT images were evaluated by radiologists and compared with images from CT scanner. Results: The results show that the reconstructed ROI image was in excellent agreement with the truth inside the ROI, obtained from images from CT scanner, and the detailed features in the ROI were quantitatively accurate. Radiologists evaluation shows that CT images reconstructed with interior tomography met diagnosis requirements. Radiation dose may be reduced up to 50% using interior tomography, depending on patient size. Conclusion: This study shows that interior tomography can be readily employed in CT imaging for radiation dose reduction. It may be especially useful in imaging obese patients, whose subcutaneous tissue is less clinically relevant but may significantly increase radiation dose

  10. Three-dimensional CT imaging of soft-tissue anatomy

    International Nuclear Information System (INIS)

    Fishman, E.K.; Ney, D.R.; Magid, D.; Kuhlman, J.E.

    1988-01-01

    Three-dimensional display of computed tomographic data has been limited to skeletal structures. This was in part related to the reconstruction algorithm used, which relied on a binary classification scheme. A new algorithm, volumetric rendering with percentage classification, provides the ability to display three-dimensional images of muscle and soft tissue. A review was conducted of images in 35 cases in which muscle and/or soft tissue were part of the clinical problem. In all cases, individual muscle groups could be clearly identified and discriminated. Branching vessels in the range of 2.3 mm could be identified. Similarly, lymph nodes could be clearly defined. High-resolution three-dimensional images were found to be useful both in providing an increased understanding of complex muscle and soft tissue anatomy and in surgical planning

  11. Differential CT Attenuation of Metabolically Active and Inactive Adipose Tissues — Preliminary Findings

    Science.gov (United States)

    Hu, Houchun H.; Chung, Sandra A.; Nayak, Krishna S.; Jackson, Hollie A.; Gilsanz, Vicente

    2010-01-01

    This study investigates differences in CT Hounsfield units (HUs) between metabolically active (brown fat) and inactive adipose tissues (white fat) due to variations in their densities. PET/CT data from 101 pediatric and adolescent patients were analyzed. Regions of metabolically active and inactive adipose tissues were identified and standard uptake values (SUVs) and HUs were measured. HUs of active brown fat were more positive (p<0.001) than inactive fat (−62.4±5.3 versus −86.7±7.0) and the difference was observed in both males and females. PMID:21245691

  12. SU-F-T-427: Utilization and Evaluation of Diagnostic CT Imaging with MAR Technique for Radiation Therapy Treatment Planning

    International Nuclear Information System (INIS)

    Xu, M; Foster, R; Parks, H; Pankuch, M

    2016-01-01

    Purpose: The objective was to utilize and evaluate diagnostic CT-MAR technique for radiation therapy treatment planning. Methods: A Toshiba-diagnostic-CT acquisition with SEMAR(Single-energy-MAR)-algorism was performed to make the metal-artifact-reduction (MAR) for patient treatment planning. CT-imaging datasets with and without SEMAR were taken on a Catphan-phantom. Two sets of CT-numbers were calibrated with the relative electron densities (RED). A tissue characterization phantom with Gammex various simulating material rods was used to establish the relationship between known REDs and corresponding CT-numbers. A GE-CT-sim acquisition was taken on the Catphan for comparison. A patient with bilateral hip arthroplasty was scanned in the radiotherapy CT-sim and the diagnostic SEMAR-CT on a flat panel. The derived SEMAR images were used as a primary CT dataset to create contours for the target, critical-structures, and for planning. A deformable registration was performed with VelocityAI to track voxel changes between SEMAR and CT-sim images. The SEMAR-CT images with minimal artifacts and high quality of geometrical and spatial integrity were employed for a treatment plan. Treatment-plans were evaluated based on deformable registration of SEMAR-CT and CT-sim dataset with assigned CT-numbers in the metal artifact regions in Eclipse v11 TPS. Results: The RED and CT-number relationships were consistent for the datasets in CT-sim and CT’s with and without SEMAR. SEMAR datasets with high image quality were used for PTV and organ delineation in the treatment planning process. For dose distribution to the PTV through the DVH analysis, the plan using CT-sim with the assigned CT-number showed a good agreement to those on deformable CT-SEMAR. Conclusion: A diagnostic-CT with MAR-algorithm can be utilized for radiotherapy treatment planning with CT-number calibrated to the RED. Treatment planning comparison and DVH shows a good agreement in the PTV and critical organs between

  13. Synchrotron microCT imaging of soft tissue in juvenile zebrafish reveals retinotectal projections

    Science.gov (United States)

    Xin, Xuying; Clark, Darin; Ang, Khai Chung; van Rossum, Damian B.; Copper, Jean; Xiao, Xianghui; La Riviere, Patrick J.; Cheng, Keith C.

    2017-02-01

    Biomedical research and clinical diagnosis would benefit greatly from full volume determinations of anatomical phenotype. Comprehensive tools for morphological phenotyping are central for the emerging field of phenomics, which requires high-throughput, systematic, accurate, and reproducible data collection from organisms affected by genetic, disease, or environmental variables. Theoretically, complete anatomical phenotyping requires the assessment of every cell type in the whole organism, but this ideal is presently untenable due to the lack of an unbiased 3D imaging method that allows histopathological assessment of any cell type despite optical opacity. Histopathology, the current clinical standard for diagnostic phenotyping, involves the microscopic study of tissue sections to assess qualitative aspects of tissue architecture, disease mechanisms, and physiological state. However, quantitative features of tissue architecture such as cellular composition and cell counting in tissue volumes can only be approximated due to characteristics of tissue sectioning, including incomplete sampling and the constraints of 2D imaging of 5 micron thick tissue slabs. We have used a small, vertebrate organism, the zebrafish, to test the potential of microCT for systematic macroscopic and microscopic morphological phenotyping. While cell resolution is routinely achieved using methods such as light sheet fluorescence microscopy and optical tomography, these methods do not provide the pancellular perspective characteristic of histology, and are constrained by the limited penetration of visible light through pigmented and opaque specimens, as characterizes zebrafish juveniles. Here, we provide an example of neuroanatomy that can be studied by microCT of stained soft tissue at 1.43 micron isotropic voxel resolution. We conclude that synchrotron microCT is a form of 3D imaging that may potentially be adopted towards more reproducible, large-scale, morphological phenotyping of optically

  14. 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.

  15. Evaluation on temporal bone CT findings of cholesteatoma

    International Nuclear Information System (INIS)

    Lee, Kun Won; Lee, Nam Joon; Kang, Eun Young; Chung, Kyoo Byung; Suh, Won Hyuck

    1989-01-01

    Cholesteatomas are thought to result from ingrowth of keratinizing squamous epithelium from external ear to middle ear. The cholesteatomas are usually diagnosed by clinical symptoms and signs, otoscopy, and plain radiograms. But various view points are emphasized radiologically before operation, leading to examine by computed tomography (CT), especially in complicated cases. We retrospectively reviewed the CT findings of cholesteatomas in 25 surgically proven cases during the period from May, 1983 to Aug, 1988. The results were as follows: 1. Most cholesteatomas showed soft tissue mass and bony erosion of ossicles (88%), attic wall and mastoid antrum (84%) on temporal bone CT scan. 2. The CT members of cholesteatomas ranged from 25 to 50 HU (avg. 33 HU). 3. Involved sites were attic (16%), antrum (28%), and both attic and antrum (56%). Other sites were middle ear cavity and external auditory canal. 4. Extra-tympanomastoid extension of cholesteatoma was intracranial abscess (8%), exposure of dural sinus (8%), and extension along with neck (4%)

  16. Evaluation of diseases of the aorta with ultrafast CT

    International Nuclear Information System (INIS)

    Eldredge, W.J.; Flicker, S.; Altin, R.S.; Naidech, H.J.

    1987-01-01

    Ultrafast CT offers several advantages over standard CT for imaging of various congenital and acquired diseases of the aorta. Scan acquisition rates of 50 msec permit evaluation of the entire aorta following a single peripheral intravenous injection of iodinated contrast medium. Pathologic aortic flow patterns may also be defined using an ECG triggered ''flow'' mode, adding another dimension to CT evaluation of the aorta. The papers shows examples of a variety of aortic diseases, including coarctation, Marfan syndrome, atherosclerotic aneurysm, dissection, and postoperative abnormalities. The advantages of the modality are stressed

  17. CT evaluation of a mycotic aneurysma

    Energy Technology Data Exchange (ETDEWEB)

    Loehr, E; Serdarevic, M; Beck, A; Wendt, F C

    1986-03-01

    Examination and localisation of mycotic aneurysm of the femoral artery in the course of typhoid fever. The diagnosis was exclusively carried out by CT and not by angiography to lower the risk of examination because the patient was suffering from chronic lymphatic leukaemia.

  18. CT evaluation of a mycotic aneurysma

    International Nuclear Information System (INIS)

    Loehr, E.; Serdarevic, M.; Beck, A.; Wendt, F.C.

    1986-01-01

    Examination and localisation of mycotic aneurysm of the femoral artery in the course of typhoid fever. The diagnosis was exclusively carried out by CT and not by angiography to lower the risk of examination because the patient was suffering from chronic lymphatic leukaemia. (orig.) [de

  19. Effectiveness of combined use of imprint cytological and histological examination in CT-guided tissue-core biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Yamagami, Takuji; Yoshimatsu, Rika; Kajiwara, Kenji; Ishikawa, Masaki; Awai, Kazuo [Hiroshima University, Department of Diagnostic Radiology, Institute and Graduate School of Biomedical Sciences, Minami-Ku, Hiroshima (Japan); Matsumoto, Tomohiro; Hasebe, Terumitsu [Tokai University Hachioji Hospital, Tokai University School of Medicine, Department of Radiology, Hachioji, Tokyo (Japan); Kakizawa, Hideaki [Hiroshima University, Department of Diagnostic Radiology, Institute and Graduate School of Biomedical Sciences, Minami-Ku, Hiroshima (Japan); Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital, Department of Diagnostic Radiology, Naka-Ku, Hiroshima (Japan); Toyoda, Naoyuki [Hiroshima University, Department of Diagnostic Radiology, Institute and Graduate School of Biomedical Sciences, Minami-Ku, Hiroshima (Japan); National Hospital Organisation Kure Medical Centre, Department of Diagnostic Radiology, Kure, Hiroshima (Japan)

    2014-05-15

    This study evaluated the efficacy of the combination of imprint cytology and histology in tissue-core percutaneous biopsy under real-time computed tomography (CT) fluoroscopic guidance. Between October 2009 and June 2013, 156 percutaneous needle biopsies were performed in our institution. Those obtained by tissue-core biopsy underwent both imprint cytological and histological examinations routinely after touch imprint cytology was performed on site to evaluate the samples' sufficiency for cytological and pathological examination. Final diagnosis was confirmed by independent surgical pathology, independent culture results or clinical follow-up. Rates of adequate specimens and precise diagnosis, by combined cytological and histological examination were 100 % (156/156) and 96.2 % (150/156), by cytology 94.4 % (152/156) and 83.3 % (130/156) and by histology 99.3 % (155/156) and 92.3 % (144/156). Precise diagnosis was achieved by combined examinations in 94.7 % (89/94) of thoracic lesions, 97.6 % (40/41) of musculoskeletal lesions, and 100 % (21/21) of abdominal, pelvic and retroperitoneal lesions. In all 104 lesions diagnosed as malignant by CT-guided biopsy and in 30 of 52 diagnosed as benign, specific cell types could be proved by combined examinations. Combined imprint cytology and histology performed after on-site touch imprint cytological evaluation improved the diagnostic ability of CT fluoroscopically guided biopsy. (orig.)

  20. Effectiveness of combined use of imprint cytological and histological examination in CT-guided tissue-core biopsy

    International Nuclear Information System (INIS)

    Yamagami, Takuji; Yoshimatsu, Rika; Kajiwara, Kenji; Ishikawa, Masaki; Awai, Kazuo; Matsumoto, Tomohiro; Hasebe, Terumitsu; Kakizawa, Hideaki; Toyoda, Naoyuki

    2014-01-01

    This study evaluated the efficacy of the combination of imprint cytology and histology in tissue-core percutaneous biopsy under real-time computed tomography (CT) fluoroscopic guidance. Between October 2009 and June 2013, 156 percutaneous needle biopsies were performed in our institution. Those obtained by tissue-core biopsy underwent both imprint cytological and histological examinations routinely after touch imprint cytology was performed on site to evaluate the samples' sufficiency for cytological and pathological examination. Final diagnosis was confirmed by independent surgical pathology, independent culture results or clinical follow-up. Rates of adequate specimens and precise diagnosis, by combined cytological and histological examination were 100 % (156/156) and 96.2 % (150/156), by cytology 94.4 % (152/156) and 83.3 % (130/156) and by histology 99.3 % (155/156) and 92.3 % (144/156). Precise diagnosis was achieved by combined examinations in 94.7 % (89/94) of thoracic lesions, 97.6 % (40/41) of musculoskeletal lesions, and 100 % (21/21) of abdominal, pelvic and retroperitoneal lesions. In all 104 lesions diagnosed as malignant by CT-guided biopsy and in 30 of 52 diagnosed as benign, specific cell types could be proved by combined examinations. Combined imprint cytology and histology performed after on-site touch imprint cytological evaluation improved the diagnostic ability of CT fluoroscopically guided biopsy. (orig.)

  1. CT in the evaluation of severe liver trauma

    International Nuclear Information System (INIS)

    Machado, Marcel Autran C.; Souza Rocha, Manoel de; Machado, Manoel C.C.; Macedo Neto, Augusto Cesar de; Maciel, Rosangela Pereira; Simonetti, Celso.

    1995-01-01

    Abdominal CT is a common examination in the evaluation of patients with blunt abdominal trauma and clinical suspicion for solid organ injury when reasons for immediate laparotomy are not present. A case of major blunt hepatic injury in a 22-year-old patient is reported. The authors present a brief review of the literature and discussion about the role of CT scan in the evaluation of hepatic trauma, surgical planning and postoperative follow-up. (author). 15 refs., 3 figs., 1 tab

  2. Primary endobronchial marginal zone B-cell lymphoma of bronchus-associated lymphoid tissue: CT findings 7 patients

    International Nuclear Information System (INIS)

    Yoon, Ra Gyoung; Kim, Mi Young; Song, Jae Woo; Chae, Eun Jin; Choi, Chang Min; Jang, Se Jin

    2013-01-01

    To investigate CT and 1 8F -fluorodeoxyglucose (1 8F -FDG) positron-emission tomography/CT findings of primary endobronchial marginal zone B-cell lymphoma of the bronchus-associated lymphoid tissue (BALT). From June 2006 through April 2012, seven patients (six female, one male; age range, 21-61 years; mean age, 49 years) were examined who were pathologically diagnosed with the primary endobronchial marginal zone B-cell lymphoma of BALT. We evaluated the locations and characteristics of the lesions on CT and 1 8F -FDG-PET/CT scans. The lesions were classified into the following three patterns: 1) solitary intraluminal nodule; 2) several tiny nodular protrusions; and 3) diffuse wall thickening. A solitary intraluminal nodule was observed in four patients (57.1%), several tiny nodular protrusion in two patients (28.6%), and diffuse wall thickening in one patient (14.3%). The lesions were categorized into 3 major locations: confined to the trachea (n 3), confined to the lobar bronchus (n = 2), and diffuse involvement of the trachea and both main bronchi (n = 2). All lesions demonstrated homogeneous iso-attenuation as compared with muscle on pre- and post-enhancement scans. Secondary findings in the lungs (n = 3; 42.9%) included postobstructive lobar atelectasis (n = 1), air trapping (n = 1), and pneumonia (n = 1). On 1 8F -FDG-PET/CT (n = 5), 4 lesions showed homogeneous uptake with maximum standardized uptake values (mSUV), ranging 2.3-5.7 (mean mSUV: 3.3). One lesion showed little FDG uptake. Primary endobronchial marginal zone B-cell lymphoma of the BALT manifests as three distinct patterns on CT, with the solitary intraluminal nodule presenting as the main pattern. Most lesions demonstrate homogeneous but weak FDG uptake on 1 8F -FDG-PET/CT.

  3. Primary endobronchial marginal zone B-cell lymphoma of bronchus-associated lymphoid tissue: CT findings 7 patients

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Ra Gyoung; Kim, Mi Young; Song, Jae Woo; Chae, Eun Jin; Choi, Chang Min; Jang, Se Jin [University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2013-04-15

    To investigate CT and 1{sup 8F}-fluorodeoxyglucose (1{sup 8F}-FDG) positron-emission tomography/CT findings of primary endobronchial marginal zone B-cell lymphoma of the bronchus-associated lymphoid tissue (BALT). From June 2006 through April 2012, seven patients (six female, one male; age range, 21-61 years; mean age, 49 years) were examined who were pathologically diagnosed with the primary endobronchial marginal zone B-cell lymphoma of BALT. We evaluated the locations and characteristics of the lesions on CT and 1{sup 8F}-FDG-PET/CT scans. The lesions were classified into the following three patterns: 1) solitary intraluminal nodule; 2) several tiny nodular protrusions; and 3) diffuse wall thickening. A solitary intraluminal nodule was observed in four patients (57.1%), several tiny nodular protrusion in two patients (28.6%), and diffuse wall thickening in one patient (14.3%). The lesions were categorized into 3 major locations: confined to the trachea (n 3), confined to the lobar bronchus (n = 2), and diffuse involvement of the trachea and both main bronchi (n = 2). All lesions demonstrated homogeneous iso-attenuation as compared with muscle on pre- and post-enhancement scans. Secondary findings in the lungs (n = 3; 42.9%) included postobstructive lobar atelectasis (n = 1), air trapping (n = 1), and pneumonia (n = 1). On 1{sup 8F}-FDG-PET/CT (n = 5), 4 lesions showed homogeneous uptake with maximum standardized uptake values (mSUV), ranging 2.3-5.7 (mean mSUV: 3.3). One lesion showed little FDG uptake. Primary endobronchial marginal zone B-cell lymphoma of the BALT manifests as three distinct patterns on CT, with the solitary intraluminal nodule presenting as the main pattern. Most lesions demonstrate homogeneous but weak FDG uptake on 1{sup 8F}-FDG-PET/CT.

  4. Experimental verification of ion stopping power prediction from dual energy CT data in tissue surrogates

    Science.gov (United States)

    Farace, Paolo

    2014-11-01

    A two-steps procedure is presented to convert dual-energy CT data to stopping power ratio (SPR), relative to water. In the first step the relative electron density (RED) is calculated from dual-energy CT-numbers by means of a bi-linear relationship: RED = a HUscH + b HUscL + c, where HUscH and HUscL are scaled units (HUsc = HU + 1000) acquired at high and low energy respectively, and the three parameters a, b and c has to be determined for each CT scanner. In the second step the RED values were converted into SPR by means of published poly-line functions, which are invariant as they do not depend on a specific CT scanner. The comparison with other methods provides encouraging results, with residual SPR error on human tissue within 1%. The distinctive features of the proposed method are its simplicity and the generality of the conversion functions.

  5. Experimental verification of ion stopping power prediction from dual energy CT data in tissue surrogates.

    Science.gov (United States)

    Farace, Paolo

    2014-11-21

    A two-steps procedure is presented to convert dual-energy CT data to stopping power ratio (SPR), relative to water. In the first step the relative electron density (RED) is calculated from dual-energy CT-numbers by means of a bi-linear relationship: RED=a HUscH+b HUscL+c, where HUscH and HUscL are scaled units (HUsc=HU+1000) acquired at high and low energy respectively, and the three parameters a, b and c has to be determined for each CT scanner. In the second step the RED values were converted into SPR by means of published poly-line functions, which are invariant as they do not depend on a specific CT scanner. The comparison with other methods provides encouraging results, with residual SPR error on human tissue within 1%. The distinctive features of the proposed method are its simplicity and the generality of the conversion functions.

  6. An algorithm to biological tissues evaluation in pediatric examinations

    International Nuclear Information System (INIS)

    Souza, R.T.F.; Miranda, J.R.A.; Alvarez, M.; Velo, A.F.; Pina, D.R.

    2011-01-01

    A prerequisite for the construction of phantoms is the quantification of the average thickness of biological tissues and the equivalence of these simulators in simulator material thicknesses. This study aim to develop an algorithm to classify and quantify tissues, based on normal distribution of CT numbers of anatomical structures found in the mean free path of the X-rays beam, using the examination histogram to carry out this evaluation. We have considered an algorithm for the determination of the equivalent biological tissues thickness from histograms. This algorithm classifies different biological tissues from tomographic exams in DICOM format and calculates the average thickness of these tissues. The founded results had revealed coherent with literature, presenting discrepancies of up to 21,6%, relative to bone tissue, analyzed for anthropomorphic phantom (RANDO). These results allow using this methodology in livings tissues, for the construction of thorax homogeneous phantoms, of just born and suckling patients, who will be used later in the optimization process of pediatrics radiographic images. (author)

  7. CT manifestations of radiation-induced change in chest tissue

    International Nuclear Information System (INIS)

    Pagani, J.J.; Libshitz, H.I.

    1982-01-01

    The computed tomographic appearance of acute and chronic radiation change in the thorax is described. Acute radiation pneumonitis demonstrates patchy, confluent regions of increased pulmonary attenuation. Chronic changes include soft tissue density fibrotic changes that blend smoothly with the pleural surfaces and adjacent mediastinal structures. Also seen are bronchiectatic changes and distortion of normal intrathoracic anatomic relationships. Both the acute and chronic changes usually make linear lateral margins with adjacent aerated lung. Development of a discrete mass or focal cavitation after the radiation changes have become stable is suspect for recurrent tumor or infection

  8. Evaluation of CT in the investigation of patellofemoral malalignment

    International Nuclear Information System (INIS)

    Zhang Quan; Huang Huangyuan; Xia Jun; Chen Wenjun

    1999-01-01

    Objective: To evaluate CT in investigating patellofemoral malalignment. Methods: CT was used to evaluate 32 patients (50 knees) with persistent patellofemoral pain and 15 asymptomatic volunteers (20 knees). Multiple mid-patellar images were obtained at 30 degree flexion. Results: Compared to controls, the patients had marked malalignment including three distinct patterns. 11 knees had lateral patellae based on high congruence angles (CA). 8 knees had tilted patellae with lower lateral patellofemoral angles (LPFA). 10 knees had both high CA and lower LPFA indicating both lateral and tilted patella. Conclusions: CT may be the optimal imaging method of evaluating the patellofemoral joint. An awareness of different patterns of malalignment is a significant advantage of CT when planning selective surgical realignment for these patients

  9. Small metal soft tissue foreign body extraction by using 3D CT guidance: A reliable method

    International Nuclear Information System (INIS)

    Tao, Kai; Xu, Sen; Liu, Xiao-yan; Liang, Jiu-long; Qiu, Tao; Tan, Jia-nan; Che, Jian-hua; Wang, Zi-hua

    2012-01-01

    Objective: To introduce a useful and accurate technique for the locating and removal of small metal foreign bodies in the soft tissues. Methods: Eight patients presented with suspected small metal foreign bodies retained in the soft tissues of various body districts. Under local anesthesia, 3–6 pieces of 5 ml syringe needles or 1 ml syringe needles were induced through three different planes around the entry point of the foreign bodies. Using these finders, the small metal FBs were confirmed under 3D CT guidance. Based on the CT findings, the soft tissues were dissected along the path of the closest needle and the FBs were easily found and removed according to the relation with the closest needle finder. Results: Eight metal foreign bodies (3 slices, 3 nails, 1 fish hook, 1 needlepoint) were successfully removed under 3D CT guidance in all patients. The procedures took between 35 min and 50 min and the operation times took between 15 min and 25 min. No complications arose after the treatment. Conclusion: 3D CT-guided technique is a good alternative for the removal of small metal foreign body retained in the soft tissues as it is relatively accurate, reliable, quick, carries a low risk of complications and can be a first-choice procedure for the extraction of small metal foreign body.

  10. Clonality evaluation in human tissues

    Directory of Open Access Journals (Sweden)

    Villamizar-Rivera, Nicolás

    2015-07-01

    Full Text Available Malignant proliferations are usually clonal. While most times the biological potential can be established through routine pathologic and clinical examinations, some cases are difficult to classify. Moreover, in some situations there are dominant clones whose analysis is important, such as in autoimmune diseases and immunodeficiency. This paper presents in an understandable way the main techniques for the study of clonality, namely: evaluation of gene rearrangements of antigen receptor, and evaluation of human antigen receptor gene.

  11. 68Ga-PSMA PET/CT in the evaluation of bone metastases in prostate cancer.

    Science.gov (United States)

    Sachpekidis, Christos; Bäumer, P; Kopka, K; Hadaschik, B A; Hohenfellner, M; Kopp-Schneider, A; Haberkorn, U; Dimitrakopoulou-Strauss, A

    2018-06-01

    The aims of this retrospective analysis were to compare 68 Ga-PSMA PET findings and low-dose CT findings (120 kV, 30 mA), and to obtain semiquantitative and quantitative 68 Ga-PSMA PET data in patients with prostate cancer (PC) bone metastases. In total, 152 PET/CT scans from 140 patients were evaluated. Of these patients, 30 had previously untreated primary PC, and 110 had biochemical relapse after treatment of primary PC. All patients underwent dynamic PET/CT scanning of the pelvis and lower abdomen as well as whole-body PET/CT with 68 Ga-PSMA-11. The PET/CT scans were analysed qualitatively (visually), semiquantitatively (SUV), and quantitatively based on a two-tissue compartment model and a noncompartmental approach leading to the extraction of the fractal dimension. Differences were considered significant for p values PET-positive and CT-positive, 65 were only 68 Ga-PSMA-positive, and 10 were only CT-positive. The Yang test showed that there were significantly more 68 Ga-PSMA PET-positive lesions than CT-positive lesions. Association analysis showed that PSA plasma levels were significantly correlated with several 68 Ga-PSMA-11-associated parameters in bone metastases, including the degree of tracer uptake (SUV average and SUV max ), its transport rate from plasma to the interstitial/intracellular compartment (K 1 ), its rate of binding to the PSMA receptor and its internalization (k 3 ), its influx rate (K i ), and its distribution heterogeneity. 68 Ga-PSMA PET/CT is a useful diagnostic tool in the detection of bone metastases in PC. 68 Ga-PSMA PET visualizes more bone metastases than low-dose CT. PSA plasma levels are significantly correlated with several 68 Ga-PSMA PET parameters.

  12. Bone quality evaluation at dental implant site using multislice CT, micro-CT, and cone beam CT.

    Science.gov (United States)

    Parsa, Azin; Ibrahim, Norliza; Hassan, Bassam; van der Stelt, Paul; Wismeijer, Daniel

    2015-01-01

    The first purpose of this study was to analyze the correlation between bone volume fraction (BV/TV) and calibrated radiographic bone density Hounsfield units (HU) in human jaws, derived from micro-CT and multislice computed tomography (MSCT), respectively. The second aim was to assess the accuracy of cone beam computed tomography (CBCT) in evaluating trabecular bone density and microstructure using MSCT and micro-CT, respectively, as reference gold standards. Twenty partially edentulous human mandibular cadavers were scanned by three types of CT modalities: MSCT (Philips, Best, the Netherlands), CBCT (3D Accuitomo 170, J Morita, Kyoto, Japan), and micro-CT (SkyScan 1173, Kontich, Belgium). Image analysis was performed using Amira (v4.1, Visage Imaging Inc., Carlsbad, CA, USA), 3Diagnosis (v5.3.1, 3diemme, Cantu, Italy), Geomagic (studio(®) 2012, Morrisville, NC, USA), and CTAn (v1.11, SkyScan). MSCT, CBCT, and micro-CT scans of each mandible were matched to select the exact region of interest (ROI). MSCT HU, micro-CT BV/TV, and CBCT gray value and bone volume fraction of each ROI were derived. Statistical analysis was performed to assess the correlations between corresponding measurement parameters. Strong correlations were observed between CBCT and MSCT density (r = 0.89) and between CBCT and micro-CT BV/TV measurements (r = 0.82). Excellent correlation was observed between MSCT HU and micro-CT BV/TV (r = 0.91). However, significant differences were found between all comparisons pairs (P micro-CT BV/TV (P = 0.147). An excellent correlation exists between bone volume fraction and bone density as assessed on micro-CT and MSCT, respectively. This suggests that bone density measurements could be used to estimate bone microstructural parameters. A strong correlation also was found between CBCT gray values and BV/TV and their gold standards, suggesting the potential of this modality in bone quality assessment at implant site. © 2013 John Wiley & Sons A/S. Published by

  13. The relevance of MRI for patient modeling in head and neck hyperthermia treatment planning: A comparison of CT and CT-MRI based tissue segmentation on simulated temperature

    International Nuclear Information System (INIS)

    Verhaart, René F.; Paulides, Margarethus M.; Fortunati, Valerio; Walsum, Theo van; Veenland, Jifke F.; Verduijn, Gerda M.; Lugt, Aad van der

    2014-01-01

    Purpose: In current clinical practice, head and neck (H and N) hyperthermia treatment planning (HTP) is solely based on computed tomography (CT) images. Magnetic resonance imaging (MRI) provides superior soft-tissue contrast over CT. The purpose of the authors’ study is to investigate the relevance of using MRI in addition to CT for patient modeling in H and N HTP. Methods: CT and MRI scans were acquired for 11 patients in an immobilization mask. Three observers manually segmented on CT, MRI T1 weighted (MRI-T1w), and MRI T2 weighted (MRI-T2w) images the following thermo-sensitive tissues: cerebrum, cerebellum, brainstem, myelum, sclera, lens, vitreous humor, and the optical nerve. For these tissues that are used for patient modeling in H and N HTP, the interobserver variation of manual tissue segmentation in CT and MRI was quantified with the mean surface distance (MSD). Next, the authors compared the impact of CT and CT and MRI based patient models on the predicted temperatures. For each tissue, the modality was selected that led to the lowest observer variation and inserted this in the combined CT and MRI based patient model (CT and MRI), after a deformable image registration. In addition, a patient model with a detailed segmentation of brain tissues (including white matter, gray matter, and cerebrospinal fluid) was created (CT and MRI db ). To quantify the relevance of MRI based segmentation for H and N HTP, the authors compared the predicted maximum temperatures in the segmented tissues (T max ) and the corresponding specific absorption rate (SAR) of the patient models based on (1) CT, (2) CT and MRI, and (3) CT and MRI db . Results: In MRI, a similar or reduced interobserver variation was found compared to CT (maximum of median MSD in CT: 0.93 mm, MRI-T1w: 0.72 mm, MRI-T2w: 0.66 mm). Only for the optical nerve the interobserver variation is significantly lower in CT compared to MRI (median MSD in CT: 0.58 mm, MRI-T1w: 1.27 mm, MRI-T2w: 1.40 mm). Patient

  14. The relevance of MRI for patient modeling in head and neck hyperthermia treatment planning: A comparison of CT and CT-MRI based tissue segmentation on simulated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Verhaart, René F., E-mail: r.f.verhaart@erasmusmc.nl; Paulides, Margarethus M. [Hyperthermia Unit, Department of Radiation Oncology, Erasmus MC - Cancer Institute, Groene Hilledijk 301, Rotterdam 3008 AE (Netherlands); Fortunati, Valerio; Walsum, Theo van; Veenland, Jifke F. [Biomedical Imaging Group of Rotterdam, Department of Medical Informatics and Radiology, Erasmus MC, Dr. Molewaterplein 50/60, Rotterdam 3015 GE (Netherlands); Verduijn, Gerda M. [Department of Radiation Oncology, Erasmus MC - Cancer Institute, Groene Hilledijk 301, Rotterdam 3008 AE (Netherlands); Lugt, Aad van der [Department of Radiology, Erasmus MC, Dr. Molewaterplein 50/60, Rotterdam 3015 GE (Netherlands)

    2014-12-15

    Purpose: In current clinical practice, head and neck (H and N) hyperthermia treatment planning (HTP) is solely based on computed tomography (CT) images. Magnetic resonance imaging (MRI) provides superior soft-tissue contrast over CT. The purpose of the authors’ study is to investigate the relevance of using MRI in addition to CT for patient modeling in H and N HTP. Methods: CT and MRI scans were acquired for 11 patients in an immobilization mask. Three observers manually segmented on CT, MRI T1 weighted (MRI-T1w), and MRI T2 weighted (MRI-T2w) images the following thermo-sensitive tissues: cerebrum, cerebellum, brainstem, myelum, sclera, lens, vitreous humor, and the optical nerve. For these tissues that are used for patient modeling in H and N HTP, the interobserver variation of manual tissue segmentation in CT and MRI was quantified with the mean surface distance (MSD). Next, the authors compared the impact of CT and CT and MRI based patient models on the predicted temperatures. For each tissue, the modality was selected that led to the lowest observer variation and inserted this in the combined CT and MRI based patient model (CT and MRI), after a deformable image registration. In addition, a patient model with a detailed segmentation of brain tissues (including white matter, gray matter, and cerebrospinal fluid) was created (CT and MRI{sub db}). To quantify the relevance of MRI based segmentation for H and N HTP, the authors compared the predicted maximum temperatures in the segmented tissues (T{sub max}) and the corresponding specific absorption rate (SAR) of the patient models based on (1) CT, (2) CT and MRI, and (3) CT and MRI{sub db}. Results: In MRI, a similar or reduced interobserver variation was found compared to CT (maximum of median MSD in CT: 0.93 mm, MRI-T1w: 0.72 mm, MRI-T2w: 0.66 mm). Only for the optical nerve the interobserver variation is significantly lower in CT compared to MRI (median MSD in CT: 0.58 mm, MRI-T1w: 1.27 mm, MRI-T2w: 1.40 mm

  15. The relevance of MRI for patient modeling in head and neck hyperthermia treatment planning: a comparison of CT and CT-MRI based tissue segmentation on simulated temperature.

    Science.gov (United States)

    Verhaart, René F; Fortunati, Valerio; Verduijn, Gerda M; van der Lugt, Aad; van Walsum, Theo; Veenland, Jifke F; Paulides, Margarethus M

    2014-12-01

    In current clinical practice, head and neck (H&N) hyperthermia treatment planning (HTP) is solely based on computed tomography (CT) images. Magnetic resonance imaging (MRI) provides superior soft-tissue contrast over CT. The purpose of the authors' study is to investigate the relevance of using MRI in addition to CT for patient modeling in H&N HTP. CT and MRI scans were acquired for 11 patients in an immobilization mask. Three observers manually segmented on CT, MRI T1 weighted (MRI-T1w), and MRI T2 weighted (MRI-T2w) images the following thermo-sensitive tissues: cerebrum, cerebellum, brainstem, myelum, sclera, lens, vitreous humor, and the optical nerve. For these tissues that are used for patient modeling in H&N HTP, the interobserver variation of manual tissue segmentation in CT and MRI was quantified with the mean surface distance (MSD). Next, the authors compared the impact of CT and CT and MRI based patient models on the predicted temperatures. For each tissue, the modality was selected that led to the lowest observer variation and inserted this in the combined CT and MRI based patient model (CT and MRI), after a deformable image registration. In addition, a patient model with a detailed segmentation of brain tissues (including white matter, gray matter, and cerebrospinal fluid) was created (CT and MRIdb). To quantify the relevance of MRI based segmentation for H&N HTP, the authors compared the predicted maximum temperatures in the segmented tissues (Tmax) and the corresponding specific absorption rate (SAR) of the patient models based on (1) CT, (2) CT and MRI, and (3) CT and MRIdb. In MRI, a similar or reduced interobserver variation was found compared to CT (maximum of median MSD in CT: 0.93 mm, MRI-T1w: 0.72 mm, MRI-T2w: 0.66 mm). Only for the optical nerve the interobserver variation is significantly lower in CT compared to MRI (median MSD in CT: 0.58 mm, MRI-T1w: 1.27 mm, MRI-T2w: 1.40 mm). Patient models based on CT (Tmax: 38.0 °C) and CT and MRI

  16. CT EVALUATION OF AZYGOESOPHAGEAL RECESS IN ADULTS

    Directory of Open Access Journals (Sweden)

    Kulamani Sahoo

    2015-02-01

    Full Text Available Azygoesophageal recess (AER is right posterior mediastinal recess . Knowledge of normal radiologic appearance and manifestations of disease in AER can facilitate the detection and diagnosis of many intrathoracic diseases ranging from infective processes to tumors involving mediastinum, lung/pleura, lymphatic system, upper gastrointestinal system (esophagus & stomach & cardio - vascular system. Aim of this study was to investigate various intrathoracic pathologies, altering the configuration of AER on CT in adults & to find out any significance with various disease processes. This study was carried out in CT center, Department of Radiodiagnosis, Krishna Institute of medical sciences, Karad from October 2012 - September 2014. CT thorax of 156 patients was studied for configuration of AER irrespective of pathology. In this study , configuration of AER was altered in descending order with pathologies belonging to following systems: Respiratory system (Lung parenchyma pathologies causing volume loss of right lower lobe particularly Koch’s , UIP , Malignancy , Pleural pathologies (Secondary more common than Primary >Lymphatic system(secondary subcarinal lymph node more common than Primary Lymphoma >Cardio - vascular system(Cardiomegaly particularly Left atrial enlargement >Gastrointestinal system ( hiatus herni a & esophageal Cancer > Mediastinum ( Koch’s of dorsal spine with paraspinal abscess.

  17. Automatic bone detection and soft tissue aware ultrasound-CT registration for computer-aided orthopedic surgery.

    Science.gov (United States)

    Wein, Wolfgang; Karamalis, Athanasios; Baumgartner, Adrian; Navab, Nassir

    2015-06-01

    The transfer of preoperative CT data into the tracking system coordinates within an operating room is of high interest for computer-aided orthopedic surgery. In this work, we introduce a solution for intra-operative ultrasound-CT registration of bones. We have developed methods for fully automatic real-time bone detection in ultrasound images and global automatic registration to CT. The bone detection algorithm uses a novel bone-specific feature descriptor and was thoroughly evaluated on both in-vivo and ex-vivo data. A global optimization strategy aligns the bone surface, followed by a soft tissue aware intensity-based registration to provide higher local registration accuracy. We evaluated the system on femur, tibia and fibula anatomy in a cadaver study with human legs, where magnetically tracked bone markers were implanted to yield ground truth information. An overall median system error of 3.7 mm was achieved on 11 datasets. Global and fully automatic registration of bones aquired with ultrasound to CT is feasible, with bone detection and tracking operating in real time for immediate feedback to the surgeon.

  18. CT and MR imaging in the evaluation of leptomeningeal metastases

    International Nuclear Information System (INIS)

    Xiao Jiahe; Wang Dayou; Deng Kaihong

    1999-01-01

    Objective: To study the manifestations of leptomeningeal metastases on CT and MR imaging, and evaluate the diagnostic significance of both modalities for this disease. Methods: Clinical and neuroradiological data of 21 cases with leptomeningeal metastases were retrospectively reviewed. In this series, 16 patients were studied by CT and 7 patients by MRI, 2 patients by both CT and MRI. Results: Abnormal enhancement of pia and subarachnoid space, appearing as diffuse pattern in 10 cases, nodular pattern in 8 cases and mixed pattern with diffuse plus nodules in 3 cases, were visualized by CE-CT and Gd-MRI. Diffuse enhancement followed the convolutions of gyri and surface of brainstem, and extended into cerebral cisterns and sulci. the foci appeared as enhanced nodules 0.2-3.0 cm in diameter and 1 or more in number. Nodules with infiltration of cerebral parenchymal were found in 4 patients. In 86% of all cases, diffuse or nodular foci occurred in basilar systems and adjacent cerebellar and cerebral sulci. There were 4 cases associated with ependymal nodular enhancement and 10 cases with widened irregular tentorial enhancement. Intracerebral metastases in 9 cases and hydrocephalus in 13 cases were found in this series. Conclusions: CE-CT and Gd-MRI are had significant clinical diagnostic value for leptomeningeal metastases, Gd-MRI is superior to CE-CT. Because of the limitation in the evaluation of leptomeningeal invasion by neoplasms on CT and MRI, definitive diagnosis of leptomeningeal metastases depends on combination of clinical and imaging data

  19. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... CD or DVD. CT images of internal organs, bones, soft tissue and blood vessels provide greater detail ... is also performed to: evaluate the extent of bone and soft tissue damage in patients with facial ...

  20. Intramuscular ganglia arising from the superior tibiofibular joint: CT and MR evaluation

    International Nuclear Information System (INIS)

    Bianchi, S.; Abdelwahab, I.F.; Kenan, S.; Zwass, A.; Ricci, G.; Palomba, G.

    1995-01-01

    To evaluate the role of magnetic resonance imaging (MRI) and computed tomography (CT) in the diagnosis of intramuscular ganglia (IMG) that arise from the superior tibiofibular joint (STFJ). Our series consisted of three men and three women. Four patients were studied by MRI, one by CT only, and two by both modalities. Contrast was used in one of the two patients studied by CT. MRI was obtained in at least two orthogonal planes to demonstrate the relation of the ganglia to STFJ. The MR and CT appearance of these ganglia was basically that of a well-defined soft tissue mass with low attenuation on CT images consistent with the presence of fluid. On MR studies, they had an isointense signal on T1-weighted images and a homogenous high-intensity signal on T2-weighted images. MRI demonstrated the attachment of these ganglia to the STFJ. CT and MRI were effective, noninvasive modalities in the evaluation of IMG. The imaging features on both modalities were consistent with the presence of fluid-containing lesions that had close proximity and were attached to the STFJ. The combination of location and the fluid consistency of these lesions facilitated the diagnosis. (orig.)

  1. Experimental bacterial meningitis in rabbit; evaluation with CT and MRI

    International Nuclear Information System (INIS)

    Seo, Jeong Jin; Kang, Heoung Keun; Chu, Sung Nam; Kim, Yun Hyeon; Jeong, Yong Yeon; Chung, Hyon De

    1996-01-01

    The purpose of this study was to evaluate the usefulness of computed tomography(CT) and magnetic resonance imaging(MRI) in experimental bacterial meningitis. CT and MR images of experimental bacterial meningitis were obtained after inoculation of 1ml suspension of 10-6/ml Staphylococcus aureus directly into the supratentorial arachnoid space of 18 New Zealand white rabbits. Each animal was studied with both pre-enhanced and post-enhanced CT and MRI at 12, 24, 48 hours and 1 week. Cerebrospinal fluid of all of 18 rabbits were sampled and cultured for bacterial growth. All of 18 rabbits had the clinical symptoms such as neck stiffness and anorexia within 24 hours after the inoculation. Cerebrospinal fluid cultures were positive for Staphylococcus aureus growth. Gd-enhanced MRI exhibited diffuse enhancement along the thickened supratentorial meninges earlier than CT. In Gd-enhanced MRI, the mean contrast enhancement along the thickened supratentorial meninges earlier than CT. In Gd-enhanced MRI, the mean contrast enhancement ratio(CER) at supratentorial meninges increased to 1.93 at 12 hours and 2.99 at 24 hours from 1.06 at 0 hour. Histologic evaluation demonstrated inflammatory cell infiltration into the meninges. MRI also identified the complications of meningitis such as ependymitis and hydrocephalus more effectively than CT. These results indicated that Fd-enhanced MRI detectred earlier the abnormal findingfs of bacterial meningitis and evaluated more effectively the complications of meningitis compared with CT. MRI was more useful than CT in evaluation of the bacterial meningitis

  2. Multidetector CT portal venography in evaluation of portosystemic collateral vessels

    International Nuclear Information System (INIS)

    Agarwal, A.; Jain, M.

    2008-01-01

    This essay shows the usefulness of multidetector CT angiography for evaluation of the splenoportal venous system, which is essential in the management of patients with portal hypertension and its complications, such as portal vein thrombosis. By providing scanning with reconstruction of thin axial source images and reformatting into thicker multiplanar reformats, multidetector CT can help to determine the extent and location of portosystemic collateral vessels in patients with portal hypertension and is probably the optimal imaging technique in this setting.

  3. Experimental bacterial meningitis in rabbit; evaluation with CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jeong Jin; Kang, Heoung Keun; Chu, Sung Nam; Kim, Yun Hyeon; Jeong, Yong Yeon; Chung, Hyon De [Chonnam Univ. Medical School, Kwangju (Korea, Republic of)

    1996-01-01

    The purpose of this study was to evaluate the usefulness of computed tomography(CT) and magnetic resonance imaging(MRI) in experimental bacterial meningitis. CT and MR images of experimental bacterial meningitis were obtained after inoculation of 1ml suspension of 10-6/ml Staphylococcus aureus directly into the supratentorial arachnoid space of 18 New Zealand white rabbits. Each animal was studied with both pre-enhanced and post-enhanced CT and MRI at 12, 24, 48 hours and 1 week. Cerebrospinal fluid of all of 18 rabbits were sampled and cultured for bacterial growth. All of 18 rabbits had the clinical symptoms such as neck stiffness and anorexia within 24 hours after the inoculation. Cerebrospinal fluid cultures were positive for Staphylococcus aureus growth. Gd-enhanced MRI exhibited diffuse enhancement along the thickened supratentorial meninges earlier than CT. In Gd-enhanced MRI, the mean contrast enhancement along the thickened supratentorial meninges earlier than CT. In Gd-enhanced MRI, the mean contrast enhancement ratio(CER) at supratentorial meninges increased to 1.93 at 12 hours and 2.99 at 24 hours from 1.06 at 0 hour. Histologic evaluation demonstrated inflammatory cell infiltration into the meninges. MRI also identified the complications of meningitis such as ependymitis and hydrocephalus more effectively than CT. These results indicated that Fd-enhanced MRI detectred earlier the abnormal findingfs of bacterial meningitis and evaluated more effectively the complications of meningitis compared with CT. MRI was more useful than CT in evaluation of the bacterial meningitis.

  4. Direct microCT imaging of non-mineralized connective tissues at high resolution.

    Science.gov (United States)

    Naveh, Gili R S; Brumfeld, Vlad; Dean, Mason; Shahar, Ron; Weiner, Steve

    2014-01-01

    The 3D imaging of soft tissues in their native state is challenging, especially when high resolution is required. An X-ray-based microCT is, to date, the best choice for high resolution 3D imaging of soft tissues. However, since X-ray attenuation of soft tissues is very low, contrasting enhancement using different staining materials is needed. The staining procedure, which also usually involves tissue fixation, causes unwanted and to some extent unknown tissue alterations. Here, we demonstrate that a method that enables 3D imaging of soft tissues without fixing and staining using an X-ray-based bench-top microCT can be applied to a variety of different tissues. With the sample mounted in a custom-made loading device inside a humidity chamber, we obtained soft tissue contrast and generated 3D images of fresh, soft tissues with a resolution of 1 micron voxel size. We identified three critical conditions which make it possible to image soft tissues: humidified environment, mechanical stabilization of the sample and phase enhancement. We demonstrate the capability of the technique using different specimens: an intervertebral disc, the non-mineralized growth plate, stingray tessellated radials (calcified cartilage) and the collagenous network of the periodontal ligament. Since the scanned specimen is fresh an interesting advantage of this technique is the ability to scan a specimen under load and track the changes of the different structures. This method offers a unique opportunity for obtaining valuable insights into 3D structure-function relationships of soft tissues.

  5. Evaluation of anemia on unenhanced CT of the thorax

    International Nuclear Information System (INIS)

    Zhang Yuzhong; Zhang Xuelin; Zhong Qun; Zhang Fan; Zhang Wensheng

    2006-01-01

    Objective: To explore the correlation between CT density of blood in Cardiac Chambers and hemoglobin concentration in blood, and to evaluate the veracity of diagnosis of aneamia on unenhanced computed tomography of the thorax. Methods: Thorax (heart) helical CT was performed in 92 patients. In each case, the CT values of the blood pool in left ventricle and ventricular septum were tested, and the ratio of blood pool/ventricular septum were calculated. The hemoglobin concentration in blood was tested. The correlation among these indexes were analysed. Results: In these factors, CT density of blood was strongly and positively correlated with hemoglobin concentration in blood (r=0.571, P=0.000), and the CT density ratio was also strongly and positively correlated with hemoglobin concentration in blood (r=0.650, P=0.000). It dramatically implies that the patient may be suffering from aneamia when the ratio is Ness than 90% (male) or 87% (female). Conclusion: Blood pool/ventricular septum CT density ratio may be as a reliable indicator for judging and grading aneamia with CT. (authors)

  6. Vocal cord paralysis due to extralaryngeal causes : evaluation with CT

    International Nuclear Information System (INIS)

    Lee, Jong Hwa; Mo, Jong Hyun; Moon, Sung Hee; Na, Dong Gyu; Byun, Hong Sik; Cho, Jae Min; Han, Boo Kyung; Son, Young Ik; Baek, Chung Whan

    1999-01-01

    To evaluate the use of CT in patients with vocal cord paralysis due to extralaryngeal causes, and to use CT for the assessment of extralaryngeal diseases causing vocal cord paralysis. We prospectively studied the results of CT in 41 patients with vocal cord paralysis in whom laryngoscopy revealed no laryngeal cause and physical examination demonstrated no definite extralaryngeal cause. The extralaryngeal cause of vocal cord palsy was determined after comprehensive clinical diagnosis. Enhanced CT scans were acquired from the skull base and continued to the level of the aorticopulmonary window. We used CT to assess the detection rate for extralaryngeal causes and to extimate the extent of extralaryngeal disease and the distribution of lesions. CT revealed that in 20 of 41 patients(49%) the extralarygeal causes of vocal paralysis were as follows : thyroid cancer(n=10), nodal disease(n=6), esophageal cancer(n=2), neurogenic tumor(n=1), aortic aneurysm(n=1). Lesions were located on the left side in 13 patients(65%), and in the tracheoesophageal groove in 15(75%). In patients with vocal cord paralysis in whom no definite lesion is seen on physical examination , CT could be a useful primary imaging method for the assessment of extralaryngeal causes

  7. Multiphasic helical CT of hepatocellular carcinoma. Evaluation after chemo embolization

    International Nuclear Information System (INIS)

    Catalano, O.; Esposito, M.; Sandomenico, F.; Siani, A.; Nunziata, A.

    2000-01-01

    The main purpose of this work is to report the personal experience with addition of contrast-enhanced multiphase helical CT to unenhanced CT (Lipiodol CT) in the evaluation of patients with hepatocellular carcinoma treated with chemoembolization and to analyze the present role of oily agent CT. It has been retrospectively reviewed the examinations of 42 consecutive patients submitted to globla chemoembolization over a 2-year period. CT was performed 18-30 days after the treatment. The Lipiodol CT study was carried out with volume acquisitions. It has been considered as nodules all well-defined areas with dense oily agent uptake; uptake itself was classified as: 0=absent, I=lower tha 10% of the tumor volume; II=lower than 50%, III=50%, IV=homogeneous. Contrast-enhanced helical CT was performed with the 2-phase technique in 28 patients and with the 3-phase technique in 14; it has been considered as nodules all well-defined and relatively homogeneous areas with hyperattenuation in the arterial phase and hypo-isoattenuation in the portal and/or delayed phase, or with hypo-isoattenuation in the arterial phase and in the portal and/or delayed phase. Lipiodol CT permitted to recognize 65 nodules (1-5/patient, mean 1.5), namely 15 grade I, 21 grade II, 20 grade III and 9 grade IV. Multiphase CT identified 6 additional nodules in 5 patients, 5 hypervascular and 1 hypovascular, and better assessed the correct morphology and volume of grade I nodules. Only 4 of 6 nodules missed on Lipiodol CT showed oily agent uptake after a new chemoembolization session. Moreover after retreatment, carried out in 6 of 9 patients with grade I uptake (11 nodules in all), it has been found persistence of the grade I pattern in 5 nodules, grade II in 5, and grade III in 1. Lipiodol CT may miss liver nodules and underestimate the volume of nodules with poor uptake. Though Lipiodol CT should still be considered slightly more sensitive than multiphase CT, in the general opinion this technique has

  8. The usefulness of CT and MR imaging in the preoperative evaluation of neoplasms of the craniofacial region

    International Nuclear Information System (INIS)

    Grzesiakowska, U.; Tacikowska, M.; Krajewski, R.; Starosciak, S.; Smorczewska, M.; Wiszniewska-Rawlik, D.

    2005-01-01

    The aim of the study was to determine the usefulness of CT and MR imaging in the preoperative evaluation of neoplasms of the craniofacial region. All the patients were treated surgically. CT and/or MR imaging was done in every patient for preoperative evaluation of soft tissue infiltration, destruction of bone structures, and metastasis of lymph nodes of the head and neck. The results of these imagings were compared with surgical evaluations and microscopic examination of postoperative specimens. Both CT and MR imaging have high accuracy in evaluating soft tissue infiltration. CT imaging is much better than MR in evaluating bony destruction. MR imaging is better in evaluating recurrent tumors, in which CT has very low specificity. MR imaging is the only method for evaluating infiltration of the central nervous system.The authors propose the following diagnostic algorithm: CT imaging for initial evaluation before treatment, MR imaging in suspected cases of infiltration of the central nervous system, and MR imaging in recurrent tumors after surgical and radiation treatment. (author)

  9. X-ray evaluation of bone tissue density in rheumatoid arthritis

    International Nuclear Information System (INIS)

    Kotlubej, O.V.; Kamenets'kij, M.S.; Tkachenko, G.D.; Momot, N.V.

    1998-01-01

    Densitometry of hand and foot films of 111 patients with rheumatoid arthritis was performed. Twelve patients underwent CT of lumbar vertebra with tomodensitometry followed by analysis of the obtained graphic histograms. Photo densitometry of plain x-ray films and histographic analysis of CT scans allows to perform quantitative evaluation of the bone tissue density in rheumatoid arthritis and to reveal osteoporosis at early stages when x-ray features of the disease are absent

  10. The CT evaluation of cephalic and cervical adenoid cystic carcinoma

    International Nuclear Information System (INIS)

    Gu Yajia; Wang Jiuhua; Wang HOngshi; Chen Tongzhen

    2000-01-01

    Objective: To evaluate the CT manifestations of cephalic and cervical adenoid cystic carcinoma (ACC). Methods: Thirty-three cases of ACC were analyzed retrospectively. Of all cases, 22 cases underwent operation and 11 cases received radiotherapy. The manifestations of CT were evaluated and compared with the clinical and pathologic results. Results: Tumors originated from parotid gland (5 cases), floor of mouth (5 cases), nasal cavity and nasopharynx (5 cases), tongue (4 cases), palate (3 cases), tracheas (3 cases), submandibular gland (2 cases), tonsilla (2 cases), maxillary sinus (2 cases), and cheek (2 cases), respectively. The CT manifestations included: (1)ethmoid density in 21 cases, partial ethmoid density in 5 cases. (2)the morphology of ACC was irregular and the growth of the tumor was amorphous in 17 cases, and the margin of the tumor was vague in 20 cases. (3)ACC often grew along the nerve with infiltration, which caused destruction of the skull base in 5 cases and atrophy of mastication muscles and/or buccinator in 3 cases. Conclusion: (1)The characteristics of cephalic and cervical adenoid cystic carcinoma on CT scans were ethmoid density, infiltrated growth, growing along the nerve with infiltration, and submucous growth. Among them, the most important manifestation, which could lead to the histologic diagnosis on CT, was ethmoid density. (2)The range of ACC was usually underestimated on CT. (3)The manifestation of tumor growth along the nerve could be apparently displayed on MRI

  11. CT diagnosis in the evaluation of vertebral trauma

    International Nuclear Information System (INIS)

    Emori, Takumi; Kadoya, Satoru; Nakamura, Tsutomu; Ito, Shotaro; Kwak, Ryungchan

    1984-01-01

    The diagnostic capability of the CT scan of the vertebral trauma and a comparison with the results of a routine roentgenogram and tomogram were studied in 11 patients. In total, there were 15 fractured vertebrae: 3 in the upper cervical, 3 in the lower cervical, and 9 in the thoracic and thoraco-lumbar vertebrae. In the detailed evaluation of the vertebral fractures, CT provided more information than plain films in all 15 fractured vertebrae, with a better visualization of the spinal bony details, particularly at the upper cervical, thoracic, and thoraco-lumbar levels, where the interpretation of the spinal abnormalities is usually difficult because of adjacent structures such as the skull and thorax. Only CT was able to demonstrate impingements on the vertebral canal by bony fragments. Post-traumatic syringomyelia was incidentally demonstrated in one patient on a plain CT. In 6 patients, conventional tomography was done, but no additional information with regard to spinal instability and spinal-cord compression was obtained. The usage of sagittal tomography was also limited, because it required a change in the patient's position, which might worsen the neurological deficits. On the other hand, a plain roentgenogram and conventional tomography were superior in the evaluation of spinal malalignment and fractures running horizontally. In summary, both plain roentgenograms and CT images provided detailed information about vertebral injury, whereas conventional tomography is judged to be inferior and not always necessary. Based on these results, our new diagnostic and therapeutic approaches using CT for the vertebral injuries were presented. (author)

  12. Cirrhosis: CT and MR imaging evaluation

    International Nuclear Information System (INIS)

    Brancatelli, Giuseppe; Federle, Michael P.; Ambrosini, Roberta; Lagalla, Roberto; Carriero, Alessandro; Midiri, Massimo; Vilgrain, Valerie

    2007-01-01

    In this article, we present the CT and MR imaging characteristics of the cirrhotic liver. We describe the altered liver morphology in different forms of viral, alcoholic and autoimmune end-stage liver disease. We present the spectrum of imaging findings in portal hypertension, such as splenomegaly, ascites and varices. We describe the patchy and lacelike patterns of fibrosis, along with the focal confluent form. The process of hepatocarcinogenesis is detailed, from regenerative to dysplastic nodules to overt hepatocellular carcinoma. Different types of non-neoplastic focal liver lesions occurring in the cirrhotic liver are discussed, including arterially enhancing nodules, hemangiomas and peribiliary cysts. We show different conditions causing liver morphology changes that can mimic cirrhosis, such as congenital hepatic fibrosis, 'pseudo-cirrhosis' due to breast metastases treated with chemotherapy, Budd-Chiari syndrome, sarcoidosis and cavernous transformation of the portal vein

  13. Cirrhosis: CT and MR imaging evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Brancatelli, Giuseppe [Sezione di Radiologia, Ospedale Specializzato in Gastroenterologia, ' Saverio de Bellis' -IRCCS, 70013 Castellana Grotte (Bari) (Italy) and Sezione di Scienze Radiologiche, Dipartimento di Biotecnologie Mediche e Medicina Legale, Universita di Palermo, Via del Vespro 127, 90127 Palermo (Italy) and Department of Radiology, University of Pittsburgh Medical Center, 200 Lothrop Street, 15213 Pittsburgh, PA (United States)]. E-mail: gbranca@yahoo.com; Federle, Michael P. [Department of Radiology, University of Pittsburgh Medical Center, 200 Lothrop Street, 15213 Pittsburgh, PA (United States); Ambrosini, Roberta [Department of Diagnostic and Interventional Radiology, ' Maggiore della Carita' University Hospital, ' A.Avogadro' Eastern Piemonte University, Corso Mazzini 18, Novara (Italy); Lagalla, Roberto [Sezione di Scienze Radiologiche, Dipartimento di Biotecnologie Mediche e Medicina Legale, Universita di Palermo, Via del Vespro 127, 90127 Palermo (Italy); Carriero, Alessandro [Department of Diagnostic and Interventional Radiology, ' Maggiore della Carita' University Hospital, ' A.Avogadro' Eastern Piemonte University, Corso Mazzini 18, Novara (Italy); Midiri, Massimo [Sezione di Scienze Radiologiche, Dipartimento di Biotecnologie Mediche e Medicina Legale, Universita di Palermo, Via del Vespro 127, 90127 Palermo (Italy); Vilgrain, Valerie [Service de Radiologie, Hopital Beaujon, 100 Boulevard du General Leclerc, 92118 Clichy (France)

    2007-01-15

    In this article, we present the CT and MR imaging characteristics of the cirrhotic liver. We describe the altered liver morphology in different forms of viral, alcoholic and autoimmune end-stage liver disease. We present the spectrum of imaging findings in portal hypertension, such as splenomegaly, ascites and varices. We describe the patchy and lacelike patterns of fibrosis, along with the focal confluent form. The process of hepatocarcinogenesis is detailed, from regenerative to dysplastic nodules to overt hepatocellular carcinoma. Different types of non-neoplastic focal liver lesions occurring in the cirrhotic liver are discussed, including arterially enhancing nodules, hemangiomas and peribiliary cysts. We show different conditions causing liver morphology changes that can mimic cirrhosis, such as congenital hepatic fibrosis, 'pseudo-cirrhosis' due to breast metastases treated with chemotherapy, Budd-Chiari syndrome, sarcoidosis and cavernous transformation of the portal vein.

  14. Foreign body extraction from soft tissue by using CT and fluoroscopic guidance: a new technique

    Energy Technology Data Exchange (ETDEWEB)

    Amoretti, Nicolas; Marcy, Pierre-Yves; Lesbats-Jacquot, Virginie; Fonquerne, Marie-Eve; Maratos, Yvonne [Centre Hospitalier Universitaire de Nice, Radiology Department, Nice (France); Hauger, Olivier [Hopital Pellegrin, Unite d' Imagerie Osteo-articulaire, CHU de Bordeaux (France); Hovorka, Istvan; Boileau, Pascal [Centre Hopitalier Universitaire de Nice, Orthopaedic Department, Nice (France)

    2010-01-15

    We report on a new minimally invasive technique for the retrieval of a surgical pin fragment after accidental migration into the soft tissue of the shoulder in two patients. The technique is performed under local anaesthesia and uses combined CT and fluoroscopic guidance. The materials used were simple, combining a bone biopsy needle and an endoscopy clamp. Pin displacement was confirmed under fluoroscopic guidance and the clamp was used to withdraw the pin to the cutaneous entry point under CT (step-by-step) guidance. The CT slices provide perfect visualisation of the vascular or nervous structures as well as perfect positioning of the extremity of the trocar relative to the material to be removed. This intervention avoids a second surgical intervention with a longer incision and avoided repeated general anaesthesia. (orig.)

  15. Unusual contiguous soft tissue spread of advanced malignant mesothelioma detected by FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu Yang; Edwards, Jamie; Williams, Hadyn; Hao, Zhong Lin; Khleif, Samir; Pucar, Darko [Medical College of Georgia at Augusta UniversityAugusta (United States)

    2017-06-15

    Malignant pleural mesothelioma (MPM) is a tumor of mesodermal origin that arises from the serosa of the pleura, peritoneum, pericardium or tunica vaginalis. MPM is well known to have a poor prognosis with a median survival time of 12 months. Accurate diagnosis, staging and restaging of MPM are crucial with [18F] flurodeoxy-D-glucose positron emission tomography (FDG PET/CT) playing an increasingly important role. Here we report a case of MPM with unusual contiguous soft tissue spread of the tumor along the dermal and fascial planes characterized by PET/CT. Given that the loco-regional tumor in the thorax was under control on PET/CT, the death of the patient was most likely associated with physiologic or metabolic causes associated with an extra-thoracic tumor.

  16. Evaluation of pelvic ring injuries using SPECT/CT

    Energy Technology Data Exchange (ETDEWEB)

    Scheyerer, Max J. [University Hospital Zurich, Division of Trauma Surgery, Department of Surgery, Zurich (Switzerland); University Medical Center, Centre for Orthopaedic and Trauma Surgery, Cologne (Germany); Huellner, Martin; Pietsch, Carsten [University Hospital Zurich, Division of Nuclear Medicine, Department of Medical Radiology, Zurich (Switzerland); Werner, Clement M.L. [University Hospital Zurich, Division of Trauma Surgery, Department of Surgery, Zurich (Switzerland); Veit-Haibach, Patrick [University Hospital Zurich, Division of Nuclear Medicine, Department of Medical Radiology, Zurich (Switzerland); University Hospital Zurich, Diagnostic and Interventional Radiology, Department of Medical Radiology, Zurich (Switzerland)

    2014-08-12

    The incidence of pelvic fractures is relatively low compared with other fracture locations. The low incidence is in great contrast to the high morbidity and mortality. Particularly in the elderly, with apparently isolated fractures of the pubic rami, these observations are believed to be due to additional occult lesions of the posterior pelvic ring. In these cases diagnosis cannot be established by conventional imaging alone and SPECT/CT is considered as a diagnostic adjunct. The aim of this study was to assess concomitant bony or soft tissue lesions within the pelvic ring in a population of patients with fractures of the anterior elements. In all patients with no obvious lesions of the posterior pelvic ring on X-rays and CT or with suspicious but inconclusive findings on CT an additional SPECT/CT was carried out in a non-acute setting within 3 days of the trauma. In all cases additional lesions within the pelvic ring were found. Most lesions were vertical sacral fractures, followed by transverse fractures, one non-dislocated fracture of the acetabulum on the side of the pubic rami fracture, and one post-traumatic dilatation of the sacroiliac joint with increased tracer uptake. According to our results after SPECT/CT all patients with pubic rami fracture suffered additional lesions, none detectable previously by X-ray or CT, within the pelvic ring. In this context SPECT/CT has proved to be very helpful in the clinical routine to visualize occult fractures and instability within the sacroiliac joint. (orig.)

  17. Paleoradiology: advanced CT in the evaluation of nine Egyptian mummies.

    Science.gov (United States)

    Hoffman, Heidi; Torres, William E; Ernst, Randy D

    2002-01-01

    Axial thin-collimation state-of-the-art spiral computed tomography (CT) was combined with sagittal and coronal reformatting, three-dimensional (3D) reconstruction, and virtual "fly-through" techniques to nondestructively study nine Egyptian mummies. These techniques provided important paleopathologic and historical information about mummification techniques, depicted anatomy in the most informative imaging plane, illustrated the soft-tissue preservation and physical appearance of mummies in superb detail, and generated an intriguing virtual tour through hollow mummified remains without harming the specimens themselves. Images generated with these methods can help archaeologists and Egyptologists understand these fascinating members of mankind and can serve as adjunct visual aids for laypersons who are interested in mummies. CT has emerged as the imaging modality of choice for the examination of Egyptian mummies due to its noninvasive cross-sectional nature and inherently superior contrast and spatial resolution. As multi-detector row CT and postprocessing tools evolve, the capabilities and applications of CT will continue to proliferate, attesting to the expanded versatility and utility of CT as a noninvasive research tool in the multidisciplinary study of Egyptian mummies. Copyright RSNA, 2002

  18. Studies on evaluation of staging of cancer of the uterine cervix by means of CT

    Energy Technology Data Exchange (ETDEWEB)

    Kakizaki, D

    1987-03-01

    The present study was undertaken to evaluate the stage classification (FIGO) by using CT in 50 cases with cancer of the uterine cervix in which the final stage had been diagnosed. An accurate diagnosis was obtained in 6 of 14 Ib cases, 14 of 21 IIa cases, 5 of 6 IIb cases, 2 of 3 IIIa cases, 3 of 3 IIIb cases and 3 of 3 IVa cases, for a total of 33 of 50 (66 %). The diagnostic rate for Ib and IIa staging was 57 %, while that for IIb or more was 87 %, but the accuracy rate in IIIb and IVa was 100 %. As the equipment, a high resolutional GE 9800 CT using a special technique was employed. Employing special pretreatment for the patient, it became possible to accurately grasp the pelvic condition of the patients. CT evaluation was related to the extent of the cervical cancer and the presence of infiltration into the vaginal wall. According to a 4-stage classification of the CT image, the extent of infiltration to surrounding parametrium and the bladder was determined. As a result, the sensitivity for evaluating invasion into surrounding tissue raised 92 %, and it showed 100 % for cases with adhesion or invasion of the bladder. Therefore, CT can an extremely effective method to determine the clinical staging of cancer of the uterine cervix.

  19. Tissue harmonic imaging in the evaluation of acute pancreatitis

    International Nuclear Information System (INIS)

    Garg, Mandeep; Sandhu, Manavjit; Sood, Bimal; Lal, Anupam; Suri, Sudha; Bhasin, Deepak

    2004-01-01

    To evaluate the role of tissue harmonic imaging (THI) in acute pancreatitis, and to compare its findings with conventional grey-scale sonography and contrast-enhanced computed tomography (CECT) scan, we evaluated 25 patients diagnosed with acute pancreatitis on clinical examination and laboratory findings. Conventional grey-scale ultrasound followed by tissue harmonic sonography was done on the same machine followed by a CECT within 12 h of the ultrasound examination. The present study showed that sonograms obtained with THI were of much better quality than those obtained conventionally, especially for the pancreatic tail. The benefits of harmonic imaging were more apparent in obese patients and in others whose body habitus was unfavourable for sonography. In the assessment of pancreatic image quality, grey-scale imaging had an accuracy of 60, 80 and 28% in relation to the head, body and tail, respectively. In comparison, THI had a far higher accuracy of 80, 92 and 60% in relation to the head, body and tail, respectively, with the superiority being most obvious in the pancreatic tail region. There were no cases in which tissue harmonic sonography provided less information than conventional sonography. However, CECT scan remained the best modality in all patients for the evaluation of acute pancreatitis. It showed superior demonstration of all the morphological changes, ranging from minimal pancreatic oedema to extensive fluid collections, necrosis and the haemorrhage that developed in fulminant severe pancreatitis. Our experience thus suggests that THI cannot replace CT scan as the gold standard in the assessment of acute pancreatitis, as it is poor in evaluating the pancreatic tail, cannot clearly distinguish phlegmon from necrosis, and is inferior to CT in the assessment of the complications of acute pancreatitis Copyright (2004) Blackwell Publishing Asia Pty Ltd

  20. Evaluation of left ventricular function by cardiac CT

    International Nuclear Information System (INIS)

    Naito, Hiroaki; Kozuka, Takahiro

    1982-01-01

    Left ventricular function was evaluated by CT, which was compared with the data of left ventriculography for various cardiac diseases. The end diastolic volume of the left ventricle can be readily computed from CT, with a satisfactory correlation with that of left ventriculography (r = 0.95). The left ventricular ejection fraction, calculated from the areal ratio of the left ventricular lumen in end-diastolic imaging to that in end-sytolic imaging, also roughly reflects left ventricular contractile function, but shows correlation with left ventriculography by only r = 0.79. Although the cardiac output is not sensitive for functional evaluation, it can be directly calculated by means of dynamic scanning and shows a satisfactory correlation with the ear piece pigment dilution (r = 0.85). Evaluation of left ventricular function by CT shows a high precision in comparison with left ventriculography, but still lacks temporal resolving power. (Chiba, N.)

  1. CT-sialographic evaluation of 19 cases of alivary gland tumors

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Tadashi [Komoro Kousei General Hospital, Nagano (Japan)

    1999-09-01

    Sixteen patients with parotid gland tumors and 3 patients with submandibular gland tumors were evaluated by CT sialography. The 19 patients were 5 to 78 years old, mean age: 57.3 years. CT sialography was performed preoperatively, and postoperative histological examination indicated that the tumors were benign in 13, a cyst in 1, malignant tumors in 4, and a malignant lymphoma in 1 patient. The tumorous lesion detection rate by CT sialography was 100%. The major duct was visualized in all patients, and the examination was informative about the special relationship between the tumor and the facial nerve. No sign of malignancy was noted in an epithelialmyoepithelial carcinoma of 10 mm in diameter on CT sialography. In 2 patients adhesion to surrounding tissues observed intraoperatively was judged to be benign tumors by CT sialography. The marginal morphology of the tumor and the presence or absence of low density areas and punctuate leakage in the interior of the tumor were useful for the judgement of malignancy of salivary gland tumors. CT sialography, which provides diverse information on the location and morphology of the tumor, should be performed early for the diagnosis of salivary gland tumors. (author)

  2. Can dual-energy CT replace perfusion CT for the functional evaluation of advanced hepatocellular carcinoma?

    Science.gov (United States)

    Mulé, Sébastien; Pigneur, Frédéric; Quelever, Ronan; Tenenhaus, Arthur; Baranes, Laurence; Richard, Philippe; Tacher, Vania; Herin, Edouard; Pasquier, Hugo; Ronot, Maxime; Rahmouni, Alain; Vilgrain, Valérie; Luciani, Alain

    2018-05-01

    To determine the degree of relationship between iodine concentrations derived from dual-energy CT (DECT) and perfusion CT parameters in patients with advanced HCC under treatment. In this single-centre IRB approved study, 16 patients with advanced HCC treated with sorafenib or radioembolization who underwent concurrent dynamic perfusion CT and multiphase DECT using a single source, fast kV switching DECT scanner were included. Written informed consent was obtained for all patients. HCC late-arterial and portal iodine concentrations, blood flow (BF)-related and blood volume (BV)-related perfusion parameters maps were calculated. Mixed-effects models of the relationship between iodine concentrations and perfusion parameters were computed. An adjusted p value (Bonferroni method) statistic (F)=28.52, padvanced HCC lesions, DECT-derived late-arterial iodine concentration is strongly related to both aBF and BV, while portal iodine concentration mainly reflects BV, offering DECT the ability to evaluate both morphological and perfusion changes. • Late-arterial iodine concentration is highly related to arterial BF and BV. • Portal iodine concentration mainly reflects tumour blood volume. • Dual-energy CT offers significantly decreased radiation dose compared with perfusion CT.

  3. Checklist and scoring system for the assessment of soft tissue preservation in CT examinations of human mummies. Application to the Tyrolean Iceman

    Energy Technology Data Exchange (ETDEWEB)

    Panzer, Stephanie [Trauma Center Murnau (Germany). Dept. of Radiology; Trauma Center Murnau and Paracelsus Medical Univ. Salzburg, Murnau (Germany). Inst. of Biomechanics; Pernter, Patrizia [Central Hospital, Bozen (Italy). Dept. of Radiodiagnostics; Piombino-Mascali, Dario; Jankauskas, Rimantas [Vilnius Univ. (Lithuania). Dept. of Anatomy, Histology and Anthropology; Zesch, Stephanie; Rosendahl, Wilfried [Reiss-Engelhorn Museen, Mannheim (Germany). German Mummy Project; Hotz, Gerhard [Natural History Museum of Basel (Switzerland). Anthropology; Zink, Albert R. [EURAC-Institute for Mummies and the Iceman, Bolzano (Italy)

    2017-12-15

    Soft tissues make a skeleton into a mummy and they allow for a diagnosis beyond osteology. Following the approach of structured reporting in clinical radiology, a recently developed checklist was used to evaluate the soft tissue preservation status of the Tyrolean Iceman using computed tomography (CT). The purpose of this study was to apply the ''Checklist and Scoring System for the Assessment of Soft Tissue Preservation in CT Examinations of Human Mummies'' to the Tyrolean Iceman, and to compare the Iceman's soft tissue preservation score to the scores calculated for other mummies. A whole-body (CT) (SOMATOM Definition Flash, Siemens, Forchheim, Germany) consisting of five scans, performed in January 2013 in the Department of Radiodiagnostics, Central Hospital, Bolzano, was used (slice thickness 0.6mm; kilovolt ranging from80 to 140). For standardized evaluation the ''CT Checklist and Scoring System for the Assessment of Soft Tissue Preservation in Human Mummies'' was used. All checkpoints under category ''A. Soft Tissues of Head and Musculoskeletal System'' and more than half in category ''B. Organs and Organ Systems'' were observed. The scoring system accounted for a total score of 153 (out of 200). The comparison of the scores between the Iceman and three mummy collections from Vilnius, Lithuania, and Palermo, Sicily, as well as one Egyptian mummy resulted in overall higher soft tissue preservation scores for the Iceman. Application of the checklist allowed for standardized assessment and documentation of the Iceman's soft tissue preservation status. The scoring system allowed for a quantitative comparison between the Iceman and other mummies. The Iceman showed remarkable soft tissue preservation.

  4. Checklist and scoring system for the assessment of soft tissue preservation in CT examinations of human mummies. Application to the Tyrolean Iceman

    International Nuclear Information System (INIS)

    Panzer, Stephanie

    2017-01-01

    Soft tissues make a skeleton into a mummy and they allow for a diagnosis beyond osteology. Following the approach of structured reporting in clinical radiology, a recently developed checklist was used to evaluate the soft tissue preservation status of the Tyrolean Iceman using computed tomography (CT). The purpose of this study was to apply the ''Checklist and Scoring System for the Assessment of Soft Tissue Preservation in CT Examinations of Human Mummies'' to the Tyrolean Iceman, and to compare the Iceman's soft tissue preservation score to the scores calculated for other mummies. A whole-body (CT) (SOMATOM Definition Flash, Siemens, Forchheim, Germany) consisting of five scans, performed in January 2013 in the Department of Radiodiagnostics, Central Hospital, Bolzano, was used (slice thickness 0.6mm; kilovolt ranging from80 to 140). For standardized evaluation the ''CT Checklist and Scoring System for the Assessment of Soft Tissue Preservation in Human Mummies'' was used. All checkpoints under category ''A. Soft Tissues of Head and Musculoskeletal System'' and more than half in category ''B. Organs and Organ Systems'' were observed. The scoring system accounted for a total score of 153 (out of 200). The comparison of the scores between the Iceman and three mummy collections from Vilnius, Lithuania, and Palermo, Sicily, as well as one Egyptian mummy resulted in overall higher soft tissue preservation scores for the Iceman. Application of the checklist allowed for standardized assessment and documentation of the Iceman's soft tissue preservation status. The scoring system allowed for a quantitative comparison between the Iceman and other mummies. The Iceman showed remarkable soft tissue preservation.

  5. Preoperative CT evaluation on nasal cavity for transsphenoidal approach

    International Nuclear Information System (INIS)

    Saeki, Naokatsu; Yamaura, Akira; Hoshi, Seiichiro; Sunada, Souichi; Sunami, Kenro

    1997-01-01

    Preoperative bone CT scans sliced parallel to the surgical plane were evaluated in 32 cases of transsphenoidal surgery. This method predicted patients with narrow nasal cavity, and helped to determine the rhinological maneuvers for providing a wider operative field. In addition, it helps to plan the need and extent of sella floor removal in re-operated cases. There was relatively little difference in the width and length of the nasal cavity between acromegalic and non-acromegalic patients. Hence, bone CT scans are useful in the preoperative evaluation of patients undergoing transsphenoidal surgery. (author)

  6. CT evaluation of preoperative cochlear implantation cochlear implantation

    International Nuclear Information System (INIS)

    Tan Xiuzhong; Zhong Lansheng; Lan Bowen; Huang Yaosheng; Du Baowen; Zhu Jian

    2004-01-01

    Objective: To evaluate CT scan as a preoperative evaluation for cochlear implantation candidates. Methods: Axial high-resolution temporal bone CT and three-dimensional reconstruction of inner ear were performed in 93 patients with sensorineural hearing loss. results: Among 81 patients with congenital sensorineural deafness, Mondini malformation was seen in 7 case (13 ears); large vestibular aqueduct syndrome (LVAS) was revealed in 5 cases (8 ears); and inner ear ossification was found in 1 case (2 ears). In 1 case (2 ears) of inner ear fibrosis, reduced cochlear signal was noted on MRI but no unremarkable findings was shown on CT scan, however, in the operation, the device could not inserted into the basal circle of the cochlea, due to fibrous obliteration. In 12 patients with post-speech deafness, chronic suppurative tympanitis was seen in 2 cases (4 ears), and inner ear ossification was revealed in 1 case (2 ears). Conclusion: CT plays an indispensable role in the pre-operative evaluation of cochlear implantation. T 2 -weighted FSE-MRI of the inner ear is a useful complementary to CT scan. (authors)

  7. Influence of Ultra-Low-Dose and Iterative Reconstructions on the Visualization of Orbital Soft Tissues on Maxillofacial CT.

    Science.gov (United States)

    Widmann, G; Juranek, D; Waldenberger, F; Schullian, P; Dennhardt, A; Hoermann, R; Steurer, M; Gassner, E-M; Puelacher, W

    2017-08-01

    Dose reduction on CT scans for surgical planning and postoperative evaluation of midface and orbital fractures is an important concern. The purpose of this study was to evaluate the variability of various low-dose and iterative reconstruction techniques on the visualization of orbital soft tissues. Contrast-to-noise ratios of the optic nerve and inferior rectus muscle and subjective scores of a human cadaver were calculated from CT with a reference dose protocol (CT dose index volume = 36.69 mGy) and a subsequent series of low-dose protocols (LDPs I-4: CT dose index volume = 4.18, 2.64, 0.99, and 0.53 mGy) with filtered back-projection (FBP) and adaptive statistical iterative reconstruction (ASIR)-50, ASIR-100, and model-based iterative reconstruction. The Dunn Multiple Comparison Test was used to compare each combination of protocols (α = .05). Compared with the reference dose protocol with FBP, the following statistically significant differences in contrast-to-noise ratios were shown (all, P ≤ .012) for the following: 1) optic nerve: LDP-I with FBP; LDP-II with FBP and ASIR-50; LDP-III with FBP, ASIR-50, and ASIR-100; and LDP-IV with FBP, ASIR-50, and ASIR-100; and 2) inferior rectus muscle: LDP-II with FBP, LDP-III with FBP and ASIR-50, and LDP-IV with FBP, ASIR-50, and ASIR-100. Model-based iterative reconstruction showed the best contrast-to-noise ratio in all images and provided similar subjective scores for LDP-II. ASIR-50 had no remarkable effect, and ASIR-100, a small effect on subjective scores. Compared with a reference dose protocol with FBP, model-based iterative reconstruction may show similar diagnostic visibility of orbital soft tissues at a CT dose index volume of 2.64 mGy. Low-dose technology and iterative reconstruction technology may redefine current reference dose levels in maxillofacial CT. © 2017 by American Journal of Neuroradiology.

  8. Tumor and normal tissue motion in the thorax during respiration: Analysis of volumetric and positional variations using 4D CT

    International Nuclear Information System (INIS)

    Weiss, Elisabeth; Wijesooriya, Krishni; Dill, S. Vaughn; Keall, Paul J.

    2007-01-01

    Purpose: To investigate temporospatial variations of tumor and normal tissue during respiration in lung cancer patients. Methods and Materials: In 14 patients, gross tumor volume (GTV) and normal tissue structures were manually contoured on four-dimensional computed tomography (4D-CT) scans. Structures were evaluated for volume changes, centroid (center of mass) motion, and phase dependence of variations relative to inspiration. Only volumetrically complete structures were used for analysis (lung in 2, heart in 8, all other structures in >10 patients). Results: During respiration, the magnitude of contoured volumes varied up to 62.5% for GTVs, 25.5% for lungs, and 12.6% for hearts. The range of maximum three-dimensional centroid movement for individual patients was 1.3-24.0 mm for GTV, 2.4-7.9 mm for heart, 5.2-12.0 mm for lungs, 0.3-5.5 mm for skin markers, 2.9-10.0 mm for trachea, and 6.6-21.7 mm for diaphragm. During respiration, the centroid positions of normal structures varied relative to the centroid position of the respective GTV by 1.5-8.1 mm for heart, 2.9-9.3 mm for lungs, 1.2-9.2 mm for skin markers, 0.9-7.1 mm for trachea, and 2.7-16.4 mm for diaphragm. Conclusion: Using 4D-CT, volumetric changes, positional alterations as well as changes in the position of contoured structures relative to the GTV were observed with large variations between individual patients. Although the interpretation of 4D-CT data has considerable uncertainty because of 4D-CT artifacts, observer variations, and the limited acquisition time, the findings might have a significant impact on treatment planning

  9. Oxygen-enhanced MRI for patients with connective tissue diseases: Comparison with thin-section CT of capability for pulmonary functional and disease severity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Nishio, Mizuho [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Koyama, Hisanobu [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Yoshikawa, Takeshi; Matsumoto, Sumiaki [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Seki, Shinichiro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Tsubakimoto, Maho [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nakagami-Gun, Okinawa (Japan); Sugimura, Kazuro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan)

    2014-02-15

    Purpose: To prospectively and directly compare oxygen-enhanced (O{sub 2}-enhanced) MRI with thin-section CT for pulmonary functional loss and disease severity assessment in connective tissue disease (CTD) patients with interstitial lung disease (ILD). Materials and methods: Thin-section CT, O{sub 2}-enhanced MRI, pulmonary function test and serum KL-6 were administered to 36 CTD patients with ILD (23 men, 13 women; mean age: 63.9 years) and nine CTD patients without ILD (six men, and three women; mean age: 62.0 years). A relative-enhancement ratio (RER) map was generated from O{sub 2}-enhanced MRI and mean relative enhancement ratio (MRER) for each subject was calculated from all ROI measurements. CT-assessed disease severity was evaluated with a visual scoring system from each of the thin-section CT data. MRER and CT-assessed disease severities of CTD patients with and without ILD were then statistically compared. To assess capability for pulmonary functional loss and disease severity assessment in CTD patients, correlations of MRER and CT-assessed disease severity with pulmonary functional parameters and serum KL-6 in all subjects were statistically determined. Results: MRER and CT-assessed disease severity showed significant differences between CTD patients with (MRER: 0.15 ± 0.08, CT-assessed disease severity: 13.0 ± 7.4%) and without ILD (MRER: 0.25 ± 0.06, p = 0.0011; CT-assessed disease severity: 1.6 ± 1.6%, p < 0.0001). MRER and CT-assessed disease severity correlated significantly with pulmonary functional parameters and serum KL-6 in all subjects (0.61 ≤ r ≤ 0.79, p < 0.05). Conclusion: O{sub 2}-enhanced MRI was found to be as useful as thin-section CT for pulmonary functional loss and disease severity assessment of CTD patients with ILD.

  10. Oxygen-enhanced MRI for patients with connective tissue diseases: Comparison with thin-section CT of capability for pulmonary functional and disease severity assessment

    International Nuclear Information System (INIS)

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

    2014-01-01

    Purpose: To prospectively and directly compare oxygen-enhanced (O 2 -enhanced) MRI with thin-section CT for pulmonary functional loss and disease severity assessment in connective tissue disease (CTD) patients with interstitial lung disease (ILD). Materials and methods: Thin-section CT, O 2 -enhanced MRI, pulmonary function test and serum KL-6 were administered to 36 CTD patients with ILD (23 men, 13 women; mean age: 63.9 years) and nine CTD patients without ILD (six men, and three women; mean age: 62.0 years). A relative-enhancement ratio (RER) map was generated from O 2 -enhanced MRI and mean relative enhancement ratio (MRER) for each subject was calculated from all ROI measurements. CT-assessed disease severity was evaluated with a visual scoring system from each of the thin-section CT data. MRER and CT-assessed disease severities of CTD patients with and without ILD were then statistically compared. To assess capability for pulmonary functional loss and disease severity assessment in CTD patients, correlations of MRER and CT-assessed disease severity with pulmonary functional parameters and serum KL-6 in all subjects were statistically determined. Results: MRER and CT-assessed disease severity showed significant differences between CTD patients with (MRER: 0.15 ± 0.08, CT-assessed disease severity: 13.0 ± 7.4%) and without ILD (MRER: 0.25 ± 0.06, p = 0.0011; CT-assessed disease severity: 1.6 ± 1.6%, p < 0.0001). MRER and CT-assessed disease severity correlated significantly with pulmonary functional parameters and serum KL-6 in all subjects (0.61 ≤ r ≤ 0.79, p < 0.05). Conclusion: O 2 -enhanced MRI was found to be as useful as thin-section CT for pulmonary functional loss and disease severity assessment of CTD patients with ILD

  11. Computed tomography in the evaluation of soft tissue tumors. Report in 124 cases

    Energy Technology Data Exchange (ETDEWEB)

    Torricelli, P; Calo, M; Boriani, S; De Santis, G

    1986-01-01

    In order to evaluate the role of Computed Tomography (CT) in prediction of nature, staging and follow-up of soft-tessue tumors, the authors examined by CT 124 patients with soft tissue neoplasms who later underwent surgery (116 cases) or fine needle biopsy (8 cases). Comparison between CT and surgical or anatomical results showed that CT was able to correctly predict the benignancy or malignancy of the masses in 76% of cases but it was very seldom able to allow an hystological prediction. On the contrary CT was found to be a very useful tool for pre-therapeutic staging and follow-up of the tumors, because it gave many diagnostic information which influenced therapeutic choiches and strategies. 39 refs.

  12. CT evaluation of cystic brain disease

    International Nuclear Information System (INIS)

    Kim, Joon Woo; Lee, Jin Woo; Joo, Yang Goo; Kim, Hong; Zeon, Seok Kil; Suh, Soo Jhi

    1987-01-01

    We retrospectively analysed CT findings of 47 cystic brain lesions of 44 patients, in which operation, biopsy or follow-up study was needed for their final diagnosis. The results were as follows: 1. The etiologic diseases of cystic brain lesions were 15 cases of brain abscess, 9 cases of astrocytoma, 5 cases of glioblastoma multiforme, 3 cases of meningioma, 5 cases of craniopharyngioma, 1 case of hemangioblastoma, 2 cases of dermoid cyst and 4 cases of metastasis. 2. We analyses the cystic lesions in view of their number, location, shape, perifocal edema, mass effect, wall and its thickness, evenness and characteristics of their inner and outer surfaces, mural nodule, calcification and contrast enhancement. a. 13.3% of brain abscess and 75% of metastases were multiple in number, but the remainder showed single lesion. b. The shape of cystic lesions were round or ovoid in 68%, lobulated in 8.5% and irregular in 23.5%, and no demonstrable difference of shape were noticed in different disease. c. In brain abscess, the wall of cystic lesions tend to be thin, even and smooth in inner surface, but the outer surfaces were equally smooth or irregular. d. Mural nodules were found in nearly half of the cases of astrocytoma, glioblastoma multiforme, metastasis and hemangioblastoma, but the brain abscess and dermoid cyst contained no mural nodule. e. Meningiomas were found to be attached to dura mater and showed thickening of the inner table of adjacent skull or of the falx. f. The presence of preceding infectious disease may be helpful in the diagnosis of brain abscess, but in 20% there were no demonstrable preceding infection. g. Lung cancer was confirmed as primary site in two of the cystic metastatic disease, but other 2 cases showed no demonstrable primary malignancy

  13. CT evaluation of cystic brain disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Joon Woo; Lee, Jin Woo; Joo, Yang Goo; Kim, Hong; Zeon, Seok Kil; Suh, Soo Jhi [Keimyung University, School of Medicine, Daegu (Korea, Republic of)

    1987-10-15

    We retrospectively analysed CT findings of 47 cystic brain lesions of 44 patients, in which operation, biopsy or follow-up study was needed for their final diagnosis. The results were as follows: 1. The etiologic diseases of cystic brain lesions were 15 cases of brain abscess, 9 cases of astrocytoma, 5 cases of glioblastoma multiforme, 3 cases of meningioma, 5 cases of craniopharyngioma, 1 case of hemangioblastoma, 2 cases of dermoid cyst and 4 cases of metastasis. 2. We analyses the cystic lesions in view of their number, location, shape, perifocal edema, mass effect, wall and its thickness, evenness and characteristics of their inner and outer surfaces, mural nodule, calcification and contrast enhancement. a. 13.3% of brain abscess and 75% of metastases were multiple in number, but the remainder showed single lesion. b. The shape of cystic lesions were round or ovoid in 68%, lobulated in 8.5% and irregular in 23.5%, and no demonstrable difference of shape were noticed in different disease. c. In brain abscess, the wall of cystic lesions tend to be thin, even and smooth in inner surface, but the outer surfaces were equally smooth or irregular. d. Mural nodules were found in nearly half of the cases of astrocytoma, glioblastoma multiforme, metastasis and hemangioblastoma, but the brain abscess and dermoid cyst contained no mural nodule. e. Meningiomas were found to be attached to dura mater and showed thickening of the inner table of adjacent skull or of the falx. f. The presence of preceding infectious disease may be helpful in the diagnosis of brain abscess, but in 20% there were no demonstrable preceding infection. g. Lung cancer was confirmed as primary site in two of the cystic metastatic disease, but other 2 cases showed no demonstrable primary malignancy.

  14. Multidetector CT evaluation of potential right lobe living donors for ...

    African Journals Online (AJOL)

    Mohamed Saied Abdelgawad

    Multidetector CT evaluation of potential right lobe living donors for liver transplantation. Mohamed Saied Abdelgawad *, Osama L. El-Abd. National Liver Institute, El-Menoufiya University, Shebein El-Koom, Alexandria, Egypt. Received 4 June 2011; accepted 18 June 2011. KEYWORDS. Liver transplantation;. Multidetector ...

  15. Utility of F-18 FDG PET/CT on the evaluation of primary bone lymphoma.

    Science.gov (United States)

    Wang, Li-Juan; Wu, Hu-Bing; Wang, Meng; Han, Yan-Jiang; Li, Hong-Sheng; Zhou, Wen-Lan; Wang, Quan-Shi

    2015-11-01

    Primary bone lymphoma (PBL) is a rare type of malignant lymphoma. Few data have been reported regarding the utility of F-18 FDG PET/CT in this disease. The aim of this study was to assess the role of F-18 FDG PET/CT in the diagnosis and therapeutic effect evaluation of PBL. A total of 19 consecutive patients with PBL were enrolled. Whole-body PET/CT scan was performed for all patients. The diagnosis of PBL was established by histopathology and immunohistochemistry. F-18 FDG PET/CT was positive in 94.7% (18/19) of patients. Uptake of FDG in lesions was intense with SUVmax of 15.14 ± 11.82. Multiple involved lesions were found in 47.4% (9/19) patients, while 52.6% presented with a single involved lesion. Based on the lesions, PET detected 98.9% (87/88) lesions. Among them, 71.6% (63/88) lesions were found to be located in axial skeleton and 28.4% (25/88) in the extremity skeleton. FDG PET/CT also found the lesions infiltrate to the surrounding soft tissue in 84.2% (16/19) patients. On the syn-modality CT, the bone destruction was noted in 43.2% (38/88) of the lesions, of which 50.0% lesions presented as slight change in bone density and 50.0% as severe change. The diagnostic sensitivity of PET was much higher than that of CT (98.9% vs. 43.2%, P=0.000). PET/CT was performed for evaluation of treatment response in 13 patients. In 12 patients with complete response(CR), PET/CT found the 25 lesions were F-18 FDG fully resoluted after treatment, however, bone destruction was still presented in 72.0% (18/25) lesions. The present study suggests that F-18 FDG PET/CT was a sensitive imaging modality for diagnosis and treatment response evaluation of PBL. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. ROLE OF MULTIDETECTOR CT IN EVALUATION OF NECK LESIONS

    Directory of Open Access Journals (Sweden)

    Reena Mathur

    2016-06-01

    Full Text Available AIMS AND OBJECTIVES To find out the role of multidetector computed tomography in the evaluation of neck lesions with respect to evaluation of the size, location and extent of tumour. Extension of tumour infiltrating into surrounding vascular and visceral structures. To correlate the findings of MD-CT with final diagnosis by biopsy. MATERIAL AND METHODS Data for the study was collected from patients with suspected neck lesions attending Department of Radio-diagnosis, J.L.N. Medical College and Associated Group of Hospitals, Ajmer, Rajasthan. A prospective study was conducted over a period (From 1st March 2014 to 31 Aug. 2015 on patients with clinically suspected neck lesions or patients who were diagnosed to have neck lesion on ultrasound and were referred to CT for further characterisation. The patients presented with symptoms of palpable neck mass and neck pain. Patients were evaluated using multidetector CT. A provisional diagnosis was made after CT scan and these findings were correlated with histopathology/surgical findings as applicable. RESULT In the present study, 97 out of 100 cases were correctly characterised by computed tomography giving an accuracy of 97%. One case of buccal carcinoma was wrongly diagnosed as benign lesion and another case of malignant lymph node was inaccurately diagnosed as benign lymph node, also another case of benign lymph node was inaccurately diagnosed as malignant lymph node. CONCLUSION Multidetector Computed Tomography of the neck has improved the localisation and characterisation of neck lesions. Accurate delineation of disease by CT scan provides a reliable preoperative diagnosis, plan for radiotherapy ports and posttreatment followup. However, histopathology still remains the gold standard as CT is not 100% accurate.

  17. CT imaging during microwave ablation: Analysis of spatial and temporal tissue contraction

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Dong; Brace, Christopher L., E-mail: clbrace@wisc.edu [Departments of Radiology and Biomedical Engineering, University of Wisconsin, Madison, Wisconsin 53705 (United States)

    2014-11-01

    Purpose: To analyze the spatial distribution and temporal development of liver tissue contraction during high-temperature ablation by using intraprocedural computed tomography (CT) imaging. Methods: A total of 46 aluminum fiducial markers were positioned in a 60 × 45 mm grid, in a single plane, around a microwave ablation antenna in each of six ex vivo bovine liver samples. Ablations were performed for 10 min at 100 W. CT data of the liver sample were acquired every 30 s during ablation. Fiducial motion between acquisitions was tracked in postprocessing and used to calculate measures of tissue contraction and contraction rates. The spatial distribution and temporal evolution of contraction were analyzed. Results: Fiducial displacement indicated that the zone measured postablation was 8.2 ± 1.8 mm (∼20%) smaller in the radial direction and 7.1 ± 1.0 mm (∼10%) shorter in the longitudinal direction than the preablation tissue dimension. Therefore, the total ablation volume was reduced from its preablation value by approximately 45%. Very little longitudinal contraction was noted in the distal portion of the ablation zone. Central tissues contracted more than 60%, which was near an estimated limit of ∼70% based on initial water content. More peripheral tissues contracted only 15% in any direction. Contraction rates peaked during the first 60 s of heating with a roughly exponential decay over time. Conclusions: Ablation zones measured posttreatment are significantly smaller than the pretreatment tissue dimensions. Tissue contraction is spatially dependent, with the greatest effect occurring in the central ablation zone. Contraction rate peaks early and decays over time.

  18. Diagnostic value of 18F-FDG-PET/CT for the follow-up and restaging of soft tissue sarcomas in adults.

    Science.gov (United States)

    Kassem, T W; Abdelaziz, O; Emad-Eldin, S

    2017-10-01

    The purpose of this study was to evaluate the clinical utility of 2-[ 18 F] fluoro-2-deoxy-D-glucose ( 18 FDG) positron emission tomography (PET)/computed tomography (CT) ( 18 F-FDG-PET/CT) in the follow-up of adult patients with soft tissue sarcomas. We prospectively evaluated 37 consecutive patients with known soft tissue sarcoma with 18 F-FDG-PET/CT examination for suspected recurrence of disease. They were 21 men and 16 women with a mean age of 49.6±10.6 (SD) years (range, 34-75years). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of 18 F-FDG-PET/CT examination were calculated on a per patient basis. 18 F-FDG-PET/CT showed an overall diagnostic accuracy of 91.8%, sensitivity of 90% and a specificity of 100%. The positive predictive value and negative predictive value were 100 and 70%, respectively. The 18 F-FDG-PET/CT interpretations were correct in 34/37 patients (91.8%). Incorrect interpretations occurred in three patients (8.1%). Reasons for false negative findings were low 18 F-FDG uptake of local recurrence in one patient and low 18 F-FDG uptake of subcentimetric inguinal lymph node metastases. 18 F-FDG-PET/CT has a high diagnostic value in the follow-up of patients with soft tissue sarcoma. Copyright © 2017 Editions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  19. Use of FDG PET/CT for investigation of febrile neutropenia: evaluation in high-risk cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Guy, Stephen D.; Tramontana, Adrian R. [Western Health, Department of Infectious Diseases, Private Bag, Footscray, Victoria (Australia); University of Melbourne, Parkville, Victoria (Australia); Worth, Leon J.; Thursky, Karin A.; Slavin, Monica A. [University of Melbourne, Parkville, Victoria (Australia); Peter MacCallum Cancer Centre, Department of Infectious Diseases, Melbourne, Victoria (Australia); Lau, Eddie; Hicks, Rodney J. [University of Melbourne, Parkville, Victoria (Australia); Peter MacCallum Cancer Centre, Centre for Cancer Imaging, Melbourne, Victoria (Australia); Seymour, John F. [University of Melbourne, Parkville, Victoria (Australia); Peter MacCallum Cancer Centre, Department of Haematology, Melbourne, Victoria (Australia)

    2012-08-15

    Febrile neutropenia (FNP) is a frequent complication of cancer care and evaluation often fails to identify a cause. [{sup 18} F]FDG PET/CT has the potential to identify inflammatory and infectious foci, but its potential role as an investigation for persistent FNP has not previously been explored. The aim of this study was to prospectively evaluate the clinical utility of FDG PET/CT in patients with cancer and severe neutropenia and five or more days of persistent fever despite antibiotic therapy. Adult patients with a diagnosis of an underlying malignancy and persistent FNP (temperature {>=}38 C and neutrophil count <500 cells/{mu}l for 5 days) underwent FDG PET/CT as an adjunct to conventional evaluation and management. The study group comprised 20 patients with FNP who fulfilled the eligibility criteria and underwent FDG PET/CT in addition to conventional evaluation. The median neutrophil count on the day of the FDG PET/CT scan was 30 cells/{mu}l (range 0-730 cells/{mu}l). Conventional evaluation identified 14 distinct sites of infection, 13 (93 %) of which were also identified by FDG PET/CT, including all deep tissue infections. FDG PET/CT identified 9 additional likely infection sites, 8 of which were subsequently confirmed as ''true positives'' by further investigations. FDG PET/CT was deemed to be of 'high' clinical impact in 15 of the 20 patients (75 %). This study supports the utility of FDG PET/CT scanning in severely neutropenic patients with five or more days of fever. Further evaluation of the contribution of FDG PET/CT in the management of FNP across a range of underlying malignancies is required. (orig.)

  20. Use of FDG PET/CT for investigation of febrile neutropenia: evaluation in high-risk cancer patients

    International Nuclear Information System (INIS)

    Guy, Stephen D.; Tramontana, Adrian R.; Worth, Leon J.; Thursky, Karin A.; Slavin, Monica A.; Lau, Eddie; Hicks, Rodney J.; Seymour, John F.

    2012-01-01

    Febrile neutropenia (FNP) is a frequent complication of cancer care and evaluation often fails to identify a cause. [ 18 F]FDG PET/CT has the potential to identify inflammatory and infectious foci, but its potential role as an investigation for persistent FNP has not previously been explored. The aim of this study was to prospectively evaluate the clinical utility of FDG PET/CT in patients with cancer and severe neutropenia and five or more days of persistent fever despite antibiotic therapy. Adult patients with a diagnosis of an underlying malignancy and persistent FNP (temperature ≥38 C and neutrophil count <500 cells/μl for 5 days) underwent FDG PET/CT as an adjunct to conventional evaluation and management. The study group comprised 20 patients with FNP who fulfilled the eligibility criteria and underwent FDG PET/CT in addition to conventional evaluation. The median neutrophil count on the day of the FDG PET/CT scan was 30 cells/μl (range 0-730 cells/μl). Conventional evaluation identified 14 distinct sites of infection, 13 (93 %) of which were also identified by FDG PET/CT, including all deep tissue infections. FDG PET/CT identified 9 additional likely infection sites, 8 of which were subsequently confirmed as ''true positives'' by further investigations. FDG PET/CT was deemed to be of 'high' clinical impact in 15 of the 20 patients (75 %). This study supports the utility of FDG PET/CT scanning in severely neutropenic patients with five or more days of fever. Further evaluation of the contribution of FDG PET/CT in the management of FNP across a range of underlying malignancies is required. (orig.)

  1. CT of laryngotracheal trauma

    International Nuclear Information System (INIS)

    Lupetin, A.R.; Daffner, R.H.

    1991-01-01

    This paper evaluates the usefulness of CT for the diagnosis of traumatic laryngotracheal abnormalities. The authors retrospectively evaluated the neck CT studies of 50 patients (36 males, 14 females; age range, 16-75 years) who presented to a level I trauma center after suffering a blunt or penetrating laryngotracheal injury. CT results were correlated with endoscopic or surgical findings in 43 cases. Three groups emerge. CT positive: hyloid bone or laryngotracheal cartilage injury; CT positive: soft-tissue injury only; and CT negative. In group 1, CT demonstrated all bony or cartilaginous injuries proved at surgery or suggested at endoscopy. CT failed to demonstrate laryngotracheal separation in 1 case. In group 2, CT demonstrated all soft-tissue injuries suggested at endoscopy. In group 3, CT findings agreed with those of endoscopy in 7 cases, but minor soft-tissue findings seen at endoscopy were missed in 3 cases. Seven patients were studied only with CT. Ct is an accurate technique for detecting bony or cartilaginous laryngotracheal traumatic abnormalities. However, laryngotracheal separation and minor soft-tissue injuries can be missed

  2. CT evaluation of the anterior epitympanic recess

    International Nuclear Information System (INIS)

    Yamasoba, Tatsuya; Kikuchi, Shigeru; Takeuchi, Naonobu; Harada, Takehiko; Nomura, Yasuya

    1991-01-01

    The structures of the anterior epitympanic recess and its surrounding tissues were examined among non-inflammatory ear, chronic otitis media with central perforation and cholesteatoma, using axial scans of high resolution computed tomography. The length and width of the recess, as well as the number of the slices where the cog was determined, had no significant differences among them. Thus, the bony structure of the recess was considered to be seldom influenced by inflammatory processes. In the non-inflammatory ear, the degree of pneumatization around the recess was similar to that of the petrous apex cells and lower than that of the mastoid cells. In the chronic otitis media with central perforation and cholesteatoma, the pneumatization of the whole temporal bones was suppressed and the tendency was also found that the cells around the recess were less pneumatized than the mastoid cells. When cholesteatoma invaded into the anterior epitympanic recess, the destruction of the bony protrusion of the lateral wall between the recess and the epitympanum was recognized, as well as the disappearance of the cog. The bony protrusion was considered to be an inferior extention of the cog toward the anterior tympanic spine. (author)

  3. Therapeutic impact of CT-guided percutaneous catheter drainage in treatment of deep tissue abscesses

    International Nuclear Information System (INIS)

    Asai, Nobuhiro; Ohkuni, Yoshihiro; Kaneko, Norihiro; Aoshima, Masahiro; Yamazaki, Ikuo; Kawamura, Yasutaka

    2013-01-01

    Combination therapy of CT-guided percutaneous drainage and antibiotics is the first-line treatment for abscesses. Its effectiveness has been demonstrated. However, the therapeutic impact of this procedure for infection treatment has never been reported. We retrospectively analyzed all 47 patients who received CT-guided percutaneous drainage for infection treatment. Patients' characteristics, pathogens isolated, antibiotics administered, technical and clinical outcomes, complications related to this procedure and therapeutic impacts were investigated. Patients were 26 males and 21 females. The mean age was 63.5 years (±18.7). The diseases targeted were 19 retroperitoneal abscesses, 18 intraabdominal abscesses, three pelvic abscesses, and seven others. As for technical outcomes, all of the 54 procedures (100%) were successful. As for clinical outcomes, 44 (93.6%) were cured and three patients (6.4%) died. No complications related to this procedure were found in this study. A total of 42 patients (88%) had a change in the management of their infection as a result of CT-guided percutaneous drainage, such as selection and discontinuation of antibiotics. In conclusion, CT-guided percutaneous drainage is a safe and favorable procedure in the treatment of deep tissue abscesses. Therapeutic impact of these procedures helped physicians make a rational decision for antibiotics selection. (author)

  4. Therapeutic impact of CT-guided percutaneous catheter drainage in treatment of deep tissue abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Asai, Nobuhiro; Ohkuni, Yoshihiro; Kaneko, Norihiro; Aoshima, Masahiro; Yamazaki, Ikuo; Kawamura, Yasutaka, E-mail: nobuhiro0204@hotmail.com [Kameda Medical Center, Chiba (Japan)

    2013-03-15

    Combination therapy of CT-guided percutaneous drainage and antibiotics is the first-line treatment for abscesses. Its effectiveness has been demonstrated. However, the therapeutic impact of this procedure for infection treatment has never been reported. We retrospectively analyzed all 47 patients who received CT-guided percutaneous drainage for infection treatment. Patients' characteristics, pathogens isolated, antibiotics administered, technical and clinical outcomes, complications related to this procedure and therapeutic impacts were investigated. Patients were 26 males and 21 females. The mean age was 63.5 years ({+-}18.7). The diseases targeted were 19 retroperitoneal abscesses, 18 intraabdominal abscesses, three pelvic abscesses, and seven others. As for technical outcomes, all of the 54 procedures (100%) were successful. As for clinical outcomes, 44 (93.6%) were cured and three patients (6.4%) died. No complications related to this procedure were found in this study. A total of 42 patients (88%) had a change in the management of their infection as a result of CT-guided percutaneous drainage, such as selection and discontinuation of antibiotics. In conclusion, CT-guided percutaneous drainage is a safe and favorable procedure in the treatment of deep tissue abscesses. Therapeutic impact of these procedures helped physicians make a rational decision for antibiotics selection. (author)

  5. Dosimetric impact of dual-energy CT tissue segmentation for low-energy prostate brachytherapy: a Monte Carlo study

    Science.gov (United States)

    Remy, Charlotte; Lalonde, Arthur; Béliveau-Nadeau, Dominic; Carrier, Jean-François; Bouchard, Hugo

    2018-01-01

    The purpose of this study is to evaluate the impact of a novel tissue characterization method using dual-energy over single-energy computed tomography (DECT and SECT) on Monte Carlo (MC) dose calculations for low-dose rate (LDR) prostate brachytherapy performed in a patient like geometry. A virtual patient geometry is created using contours from a real patient pelvis CT scan, where known elemental compositions and varying densities are overwritten in each voxel. A second phantom is made with additional calcifications. Both phantoms are the ground truth with which all results are compared. Simulated CT images are generated from them using attenuation coefficients taken from the XCOM database with a 100 kVp spectrum for SECT and 80 and 140Sn kVp for DECT. Tissue segmentation for Monte Carlo dose calculation is made using a stoichiometric calibration method for the simulated SECT images. For the DECT images, Bayesian eigentissue decomposition is used. A LDR prostate brachytherapy plan is defined with 125I sources and then calculated using the EGSnrc user-code Brachydose for each case. Dose distributions and dose-volume histograms (DVH) are compared to ground truth to assess the accuracy of tissue segmentation. For noiseless images, DECT-based tissue segmentation outperforms the SECT procedure with a root mean square error (RMS) on relative errors on dose distributions respectively of 2.39% versus 7.77%, and provides DVHs closest to the reference DVHs for all tissues. For a medium level of CT noise, Bayesian eigentissue decomposition still performs better on the overall dose calculation as the RMS error is found to be of 7.83% compared to 9.15% for SECT. Both methods give a similar DVH for the prostate while the DECT segmentation remains more accurate for organs at risk and in presence of calcifications, with less than 5% of RMS errors within the calcifications versus up to 154% for SECT. In a patient-like geometry, DECT-based tissue segmentation provides dose

  6. Site-matched assessment of structural and tissue properties of cortical bone using scanning acoustic microscopy and synchrotron radiation μCT

    International Nuclear Information System (INIS)

    Raum, K; Leguerney, I; Chandelier, F; Talmant, M; Saied, A; Peyrin, F; Laugier, P

    2006-01-01

    200 MHz scanning acoustic microscopy (SAM) and synchrotron radiation μCT (SR-μCT) were used to assess microstructural parameters and tissue properties in site-matched regions of interest in cortical bone. Anterior and postero-lateral regions of ten cross sections from human cortical radius were explored. Structural parameters, including diameter and number of Haversian canals per cortical area (Ca.Dm, N.Ca/Ar) and porosity Po were assessed with both methods using a custom-developed image fusion and analysis software. Acoustic impedance Z and degree of mineralization of bone DMB were extracted separately for osteonal and interstitial tissues from the fused images. Structural parameter estimations obtained from radiographic and acoustic images were almost identical. DMB and impedance values were in the range between 0.77 and 1.28 g cm -3 and 5.13 and 12.1 Mrayl, respectively. Interindividual and regional variations were observed, whereas the strongest difference was found between osteonal and interstitial tissues (Z: 7.2 ± 1.1 Mrayl versus 9.3 ± 1.0 Mrayl, DMB: 1.06 ± 0.07 g cm -3 versus 1.16 ± 0.05 g cm -3 , paired t-test, p 2 = 0.174, p -4 ) and for the pooled (osteonal and interstitial) data. The regression of the pooled osteonal and interstitial tissue data follows a second-order polynomial (R 2 = 0.39, p -4 ). Both modalities fulfil the requirement for a simultaneous evaluation of cortical bone microstructure and material properties at the tissue level. While SAM inspection is limited to the evaluation of carefully prepared sample surfaces, SR-μCT provides volumetric information on the tissue without substantial preparation requirements. However, SAM provides a quantitative estimate of elastic properties at the tissue level that cannot be captured by SR-μCT

  7. X-ray and CT findings of soft tissue and bone infections secondary to acquired immunodeficiency syndrome

    International Nuclear Information System (INIS)

    Jiang Songfeng; Liu Jinxin; Chen Bihua; Zhang Lieguang; Gan Qingxin; Huang Deyang

    2011-01-01

    Objective: To summarize X-ray and CT findings of soft tissue and bone infections secondary to acquired immunodeficiency syndrome (AIDS). Methods: The data of X-ray and CT findings of soft tissue and bone infections in 18 patients with AIDS were retrospectively collected and analyzed. Results: Of 18 patients with AIDS, the CT features of soft tissue demonstrated that subcutaneous patchy high density in 1 case which considered as cellulitis, round low density lesions with ring enhancement in 6 cases which considered as soft tissue abscesses, heterogeneous density lesions with peripheral enhancement in 1 case which considered as pyomyositis. Of 18 patients with AIDS, septic arthritis was found in 4 cases involving knee lesion in 3 cases and hip lesion. In the 4 case, the X-ray films showed bony destruction in 2 cases and the CT showed bone destruction in 3 cases and arthroedema in 4 cases. Of 18 patients with AIDS, osteomyelitis was found in 9 cases of which tuberculosis was considered in. 8 cases and vertebral involvement in 6 cases. In the 9 cases, the X-ray films and CT displayed bony destruction, hyperostosis, small sequestra, and intervertebral space narrowing. Of 18 patients with AIDS, costal lesions were found in 3 cases in which the CT showed expandable bony destruction. Of 18 patients with AIDS, ilium and sacroiliac joint lesions were found in 1 case in which the X-ray films and CT showed bony destruction, sequestra, and joint widening. Of 18 patients with AIDS, chronic pyogenic osteomyelitis of femur was found in 1 case in which the X-ray films showed bony destruction, hyperostosis osteosclerosis, and periosteal reaction. Conclusion: The X-ray and CT features of soft tissue and bone infections secondary to AIDS are characterized. The X-ray and CT are useful tools to early diagnose soft tissue and bone infections secondary to AIDS. (authors)

  8. Evaluation of high-resolution CT after tympanoplasty

    International Nuclear Information System (INIS)

    Torizuka, T.; Hayakawa, K.; Sato, Y.; Tanaka, F.; Okuno, Y.

    1991-01-01

    This paper reports on the condition of the middle ear cavity following tympanoplasty which is always of great interest to radiologists and otosurgeons. This study consisted of 21 patients who had various types of tympanoplasty (types I-IV) for chronic otitis media and cholesteatoma by using high-resolution CT (HRCT). HRCT following tympanoplasty was a valuable method for assessing the middle ear aeration and the state of ossicular reconstruction, including stapes prosthesis, although in some cases of soft-tissue mass in the middle ear it was necessary to correlate with clinical findings in order to differentiate between granulation and recurrence

  9. Evaluation of recovery in hydronephrosis using renal functional CT studies

    International Nuclear Information System (INIS)

    Watanabe, Kiyotaka

    1985-01-01

    Using renal functional CT studies, we studied 22 patients who underwent surgical treatment for unilateral hydronephrosis. The tissue-plasma ratio of contrast enhancement (TPR), which is an indicator of renal function per unit of parenchymal volume, improved after the operation. On the other hand, the renal parenchymal volume (PV) decreased in proportion to the shrinkage of the kidney. The pre and postoperative values of renal functional index (RFI), the product of the TPR and PV, showed a good correlation (r=0.928, p<0.01). Therefore, RFI values were found to be useful for assessing the recovery of hydronephrosis. (author)

  10. Role of 18F-FDG PET/CT in Posttreatment Evaluation of Anal Carcinoma.

    Science.gov (United States)

    Houard, Clémence; Pinaquy, Jean-Baptiste; Mesguich, Charles; Henriques de Figueiredo, Bénédicte; Cazeau, Anne-Laure; Allard, Jean-Baptiste; Laharie, Hortense; Bordenave, Laurence; Fernandez, Philippe; Vendrely, Véronique

    2017-09-01

    The aim of this study was to evaluate the relevance of PET/CT and 18 F-FDG as a strategy for response evaluation after chemoradiotherapy for anal cancer. For this, the performance of posttreatment 18 F-FDG PET/CT, the impact on patient care, and the predictive value of metabolic response were assessed. Methods: This was a retrospective and multicenter analysis of 87 patients treated by chemoradiotherapy for anal squamous cell carcinoma between October 2007 and October 2013. All patients underwent systematic posttreatment 18 F-FDG PET/CT and were followed with at least a clinical examination every 4 mo for 2 y and every 6 mo thereafter. Disease progression was confirmed by biopsy for all patients in the case of local recurrence before surgery. Kaplan-Meier and Cox regression models were used to test for associations between metabolic or clinical endpoints and progression-free survival (PFS) or cause-specific survival (CSS). Results: The median follow-up was 25 mo. 18 F-FDG PET/CT was performed 1-8 mo (median, 4 mo) after completion of chemoradiotherapy. Overall, 25 patients relapsed and 13 died. The posttherapy 18 F-FDG PET/CT did not show any abnormal 18 F-FDG uptake (complete metabolic response [CMR]) in 55 patients whereas 32 displayed incomplete response (non-CMR): 15 patients with partial response and 17 with disease progression. The sensitivity of 18 F-FDG PET/CT to detect residual tumor tissue was 92% (95% confidence interval [CI], 75%-97%), specificity was 85% (95% CI, 75%-92%), positive predictive value was 72% (95% CI, 61%-90%), and negative predictive value was 96.4% (95% CI, 90%-98.7%). The 2-y PFS was 96% (95% CI, 90-100) for patients with CMR and 28% (95% CI, 14-47) for non-CMR patients ( P PET/CT changed patient management in 14 cases (16%), with relevant modifications in 12 (14%). A Cox proportional hazards model of survival outcome indicated that a CMR was the only significant predictor of PFS and CSS ( P PET/CT shows good accuracy in posttreatment

  11. Chronic ankle instability: evaluation with stress radiography, CT and CT arthrography

    International Nuclear Information System (INIS)

    Faure, Ch.; Deplus, F.; Bochu, M.; Besse, J.L.; Moyen, B.

    1997-01-01

    We retrospectively evaluated the anterior talo-fibular ligament and the tarsal sinus of 17 patients who had complained of chronic ankle external instability. This study based on both surgery and CT-arthrography findings shows the pathologic or normal aspects of the talo-fibular anterior ligament (normal, lax, fibrosis residue, ruptured). It confirms the good anatomic analysis of the tarsal sinus, i particular the anterior talo-calcaneal interosseous ligament and the search for fibrosis. We underline that capsular distension due to subtalar laxity is not detected with medical imaging. Compared with surgery (all patients), CT arthrography demonstrated the different aspects of the anterior talo fibular ligament injuries (normal, lax, discontinuous). (authors)

  12. 18FFDG PET in evaluating malignancies compared with CT, MRI and pathology in 58 cases

    International Nuclear Information System (INIS)

    Li, L.

    2000-01-01

    This article discussed the practical application of 18 F-FDG PET imaging techniques to depict, state, or define recurrences for five important malignancies: lung cancer, colorectal and head-and-neck cancer, intracranial malignant glioma and primary or secondary hepatic malignant diseases. And comparisons of 18 F-FDG PET with CT, MRI imaging were addressed specifically. We reviewed our initial experience with 48 malignant and ten non-malignant cases. Among malignant group, 36 cases were confirmed by operation or biopsy, Other ten non-malignant diseases, including brain infarction, post-radiotherapy necrosis or scar and lung abscesses were followed with CT or MRI at least 6 months. All patients received intravenous administration of 18 F-FDG 10-15 mCi, followed by a 40 minutes uptake phase, and subsequent imaged using a Siemens ECAT 931 whole-body scanner with resolution of 4 mm FWHM in the center of the field of view. Filtered back projection reconstruction was used to display attenuated or non-attenuated corrected images. The result of 18 F-FDG PET was retrospectively evaluated to assess the degree of uptake of 18 F-FDG PET in the tumor tissues and compared with CT, MRI and pathology. CT and MRI exam were taken before or after PET study in two weeks. 18 F-FDG PET scans showed a significantly increased FDG metabolism in 47 malignant lesions, The tumor / normal tissue FDG uptake rate were 4.16 ±2.11. In 47 cases with neoplasm, 18 F-FDG PET findings were constant with or further confirmed the CT or MRI diagnosis in 35/47 (74.5%) and 12/47 (253%) cases. Another one small intracranial metastasis ( 18 F-FDG PET imaging in oncology has demonstrated powerful advantage in characterizing tumor lesions, differentiating recurrent disease from treatment effects, staging tumors, evaluating the extent of disease, and monitoring therapy. But 18 F-FDG PET still cant replace CT or MRI in malignance diagnosis. It will be used to approach and hopefully answer the difficult diagnosis

  13. Medial depression with bony dehiscence of lamina papyracea as an anatomic variation: CT evaluation

    International Nuclear Information System (INIS)

    Na, Sun Young; Lee, Young Uk; Youn, Eun Kyung; Suh, Sang Gyung; Kim, Dong Hyun

    1994-01-01

    To evaluate the incidence and CT findings of the medial depression and bony dehiscence of lamina papyracea as an anatomic variation. 1472 PNS CTs of the patients with symptoms of chronic sinusitis were retrospectively evaluated. The total incidence of depressed lamina papyracea as an anatomic variation was 3.5%(52/1472) on PNS CT. There was a statistically significant correlation between the increasing age and the incidence of depressed lamina papyracea. Depression of lamina papyracea anterior to the basal lamella were more common than those of the posterior depression. Associated findings were herniation of adjacent fatty tissue in all cases and the medial bowing and hypertrophied configuration of the medial rectus muscle without significant herniation in 19 cases(34%). Nontraumatic, asymptomatic depression with bony dehiscence of lamina papyracea as an anatomic variation is not uncommon with the incidence of 3.5%. Recognition of its existence and degree may be helpful in avoiding various ocular complication during ethmoid surgery

  14. Comparison of the 68Ga-DOTATATA PET/CT, FDG PET/CT, and MIBG SPECT/CT in the Evaluation of Suspected Primary Pheochromocytomas and Paragangliomas.

    Science.gov (United States)

    Jing, Hongli; Li, Fang; Wang, Ling; Wang, Zhenghua; Li, Wei; Huo, Li; Zhang, Jingjing

    2017-07-01

    Anatomical imaging modalities including CT and MRI are the mainstay of evaluation of primary pheochromocytoma or paraganglioma. However, nuclear medicine imaging is frequently necessary to determine the nature of the lesions. The purpose of this investigation is to assess which commonly used nuclear medicine modality might have a better diagnostic value in this clinical setting. Eight patients who had been suspected of having either primary pheochromocytoma or primary paraganglioma and 1 patient with known pheochromocytoma were included in the analysis. Among the 8 patients without known diagnosis, 7 had been suggested by anatomical imaging modalities, whereas one of them presented with initial negative anatomical imaging interpretation. All of 9 patients underwent Ga-DOTATATA PET/CT, FDG PET/CT, and MIBG SPECT/CT for further evaluation. The imaging findings were compared with postsurgical pathology and follow-up. Both Ga-DOTATATA PET/CT and MIBG SPECT/CT accurately identified 9 primary tumors, whereas FDG PET/CT showed increased activity in 8 of 9 primary tumors. Both Ga-DOTATATA and FDG PET/CT are able to detect associated extra-adrenal lesions not shown on MIBG study in patients with multiple endocrine neoplasia syndrome. Ga-DOTATATA PET/CT could be the nuclear medicine imaging choice to evaluate suspected primary pheochromocytoma or paraganglioma, especially in the situation of multiple endocrine neoplasia syndrome.

  15. Soft-tissue imaging with C-arm cone-beam CT using statistical reconstruction

    International Nuclear Information System (INIS)

    Wang, Adam S; Stayman, J Webster; Otake, Yoshito; Siewerdsen, Jeffrey H; Kleinszig, Gerhard; Vogt, Sebastian; Gallia, Gary L; Khanna, A Jay

    2014-01-01

    The potential for statistical image reconstruction methods such as penalized-likelihood (PL) to improve C-arm cone-beam CT (CBCT) soft-tissue visualization for intraoperative imaging over conventional filtered backprojection (FBP) is assessed in this work by making a fair comparison in relation to soft-tissue performance. A prototype mobile C-arm was used to scan anthropomorphic head and abdomen phantoms as well as a cadaveric torso at doses substantially lower than typical values in diagnostic CT, and the effects of dose reduction via tube current reduction and sparse sampling were also compared. Matched spatial resolution between PL and FBP was determined by the edge spread function of low-contrast (∼40–80 HU) spheres in the phantoms, which were representative of soft-tissue imaging tasks. PL using the non-quadratic Huber penalty was found to substantially reduce noise relative to FBP, especially at lower spatial resolution where PL provides a contrast-to-noise ratio increase up to 1.4–2.2× over FBP at 50% dose reduction across all objects. Comparison of sampling strategies indicates that soft-tissue imaging benefits from fully sampled acquisitions at dose above ∼1.7 mGy and benefits from 50% sparsity at dose below ∼1.0 mGy. Therefore, an appropriate sampling strategy along with the improved low-contrast visualization offered by statistical reconstruction demonstrates the potential for extending intraoperative C-arm CBCT to applications in soft-tissue interventions in neurosurgery as well as thoracic and abdominal surgeries by overcoming conventional tradeoffs in noise, spatial resolution, and dose. (paper)

  16. CT-based compartmental quantification of adipose tissue versus body metrics in colorectal cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Nattenmueller, Johanna; Hoegenauer, Hanna; Grenacher, Lars; Kauczor, Hans-Ulrich [University Hospital, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany); Boehm, Juergen; Ulrich, Cornelia [Huntsman Cancer Institute, Department of Population Health Sciences, Salt Lake City, UT (United States); Scherer, Dominique; Paskow, Michael; Gigic, Biljana; Schrotz-King, Petra [National Center for Tumor Diseases and German Cancer Research Center, Division of Preventive Oncology, Heidelberg (Germany)

    2016-11-15

    While obesity is considered a prognostic factor in colorectal cancer (CRC), there is increasing evidence that not simply body mass index (BMI) alone but specifically abdominal fat distribution is what matters. As part of the ColoCare study, this study measured the distribution of adipose tissue compartments in CRC patients and aimed to identify the body metric that best correlates with these measurements as a useful proxy for adipose tissue distribution. In 120 newly-diagnosed CRC patients who underwent multidetector computed tomography (CT), densitometric quantification of total (TFA), visceral (VFA), intraperitoneal (IFA), retroperitoneal (RFA), and subcutaneous fat area (SFA), as well as the M. erector spinae and psoas was performed to test the association with gender, age, tumor stage, metabolic equivalents, BMI, waist-to-height (WHtR) and waist-to-hip ratio (WHR). VFA was 28.8 % higher in men (p{sub VFA}<0.0001) and 30.5 % higher in patients older than 61 years (p{sub VFA}<0.0001). WHtR correlated best with all adipose tissue compartments (r{sub VFA}=0.69, r{sub TFA}=0.84, p<0.0001) and visceral-to-subcutaneous-fat-ratio (VFR, r{sub VFR}=0.22, p=<0.05). Patients with tumor stages III/IV showed significantly lower overall adipose tissue than I/II. Increased M. erector spinae mass was inversely correlated with all compartments. Densitometric quantification on CT is a highly reproducible and reliable method to show fat distribution across adipose tissue compartments. This distribution might be best reflected by WHtR, rather than by BMI or WHR. (orig.)

  17. The effects of thyroid hormones on brown adipose tissue in humans: a PET-CT study.

    Science.gov (United States)

    Zhang, Qiongyue; Miao, Qing; Ye, Hongying; Zhang, Zhaoyun; Zuo, Chuantao; Hua, Fengchun; Guan, Yihui; Li, Yiming

    2014-09-01

    Brown adipose tissue (BAT) is important for energy expenditure through thermogenesis, although its regulatory factors are not well known in humans. There is evidence suggesting that thyroid hormones affect BAT functions in some mammals, but the effects of thyroid hormones on BAT activity in humans are still unclear. The aim of this study was to investigate the effects of thyroid hormones on glucose metabolism of BAT and other organs in humans. Nine Graves' disease-caused hyperthyroid patients who were newly diagnosed and untreated were studied. Putative brown adipose tissue activity was determined by the integrated ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron-emission tomography and computed tomography (PET-CT). All hyperthyroid patients were treated with methimazole and had been monitored until their symptoms disappeared and thyroid hormone levels returned to normal. At the end, a second PET-CT scan was performed. The average follow-up period was 77 days. Meanwhile, compared with a group of seventy-five brown adipose tissue-negative controls, thyroid hormones of seventy-five BAT-positive healthy subjects were measured. Active brown adipose tissue was not present in any of the hyperthyroid patients. However, one patient with normalized thyroid function showed active BAT after therapy. The free T3 levels and free T4 levels were significantly lower in the 75 BAT-positive subjects than in the BAT-negative subjects. All hyperthyroid patients showed symmetrically increased uptake of fluorodeoxyglucose in skeletal muscles before treatment, whereas, the standardized uptake value was substantially decreased after treatment. Abnormally high circulating thyroid hormone levels may not increase brown adipose tissue activity, which may be limited by the increased obligatory thermogenesis of muscle in adult humans. Copyright © 2014 John Wiley & Sons, Ltd.

  18. CT-based compartmental quantification of adipose tissue versus body metrics in colorectal cancer patients

    International Nuclear Information System (INIS)

    Nattenmueller, Johanna; Hoegenauer, Hanna; Grenacher, Lars; Kauczor, Hans-Ulrich; Boehm, Juergen; Ulrich, Cornelia; Scherer, Dominique; Paskow, Michael; Gigic, Biljana; Schrotz-King, Petra

    2016-01-01

    While obesity is considered a prognostic factor in colorectal cancer (CRC), there is increasing evidence that not simply body mass index (BMI) alone but specifically abdominal fat distribution is what matters. As part of the ColoCare study, this study measured the distribution of adipose tissue compartments in CRC patients and aimed to identify the body metric that best correlates with these measurements as a useful proxy for adipose tissue distribution. In 120 newly-diagnosed CRC patients who underwent multidetector computed tomography (CT), densitometric quantification of total (TFA), visceral (VFA), intraperitoneal (IFA), retroperitoneal (RFA), and subcutaneous fat area (SFA), as well as the M. erector spinae and psoas was performed to test the association with gender, age, tumor stage, metabolic equivalents, BMI, waist-to-height (WHtR) and waist-to-hip ratio (WHR). VFA was 28.8 % higher in men (p_V_F_A<0.0001) and 30.5 % higher in patients older than 61 years (p_V_F_A<0.0001). WHtR correlated best with all adipose tissue compartments (r_V_F_A=0.69, r_T_F_A=0.84, p<0.0001) and visceral-to-subcutaneous-fat-ratio (VFR, r_V_F_R=0.22, p=<0.05). Patients with tumor stages III/IV showed significantly lower overall adipose tissue than I/II. Increased M. erector spinae mass was inversely correlated with all compartments. Densitometric quantification on CT is a highly reproducible and reliable method to show fat distribution across adipose tissue compartments. This distribution might be best reflected by WHtR, rather than by BMI or WHR. (orig.)

  19. New approach to detect and classify stroke in skull CT images via analysis of brain tissue densities.

    Science.gov (United States)

    Rebouças Filho, Pedro P; Sarmento, Róger Moura; Holanda, Gabriel Bandeira; de Alencar Lima, Daniel

    2017-09-01

    Cerebral vascular accident (CVA), also known as stroke, is an important health problem worldwide and it affects 16 million people worldwide every year. About 30% of those that have a stroke die and 40% remain with serious physical limitations. However, recovery in the damaged region is possible if treatment is performed immediately. In the case of a stroke, Computed Tomography (CT) is the most appropriate technique to confirm the occurrence and to investigate its extent and severity. Stroke is an emergency problem for which early identification and measures are difficult; however, computer-aided diagnoses (CAD) can play an important role in obtaining information imperceptible to the human eye. Thus, this work proposes a new method for extracting features based on radiological density patterns of the brain, called Analysis of Brain Tissue Density (ABTD). The proposed method is a specific approach applied to CT images to identify and classify the occurrence of stroke diseases. The evaluation of the results of the ABTD extractor proposed in this paper were compared with extractors already established in the literature, such as features from Gray-Level Co-Occurrence Matrix (GLCM), Local binary patterns (LBP), Central Moments (CM), Statistical Moments (SM), Hu's Moment (HM) and Zernike's Moments (ZM). Using a database of 420 CT images of the skull, each extractor was applied with the classifiers such as MLP, SVM, kNN, OPF and Bayesian to classify if a CT image represented a healthy brain or one with an ischemic or hemorrhagic stroke. ABTD had the shortest extraction time and the highest average accuracy (99.30%) when combined with OPF using the Euclidean distance. Also, the average accuracy values for all classifiers were higher than 95%. The relevance of the results demonstrated that the ABTD method is a useful algorithm to extract features that can potentially be integrated with CAD systems to assist in stroke diagnosis. Copyright © 2017 Elsevier B.V. All rights

  20. Dosimetric comparison of stereotactic body radiotherapy using 4D CT and multiphase CT images for treatment planning of lung cancer: Evaluation of the impact on daily dose coverage

    International Nuclear Information System (INIS)

    Wang Lu; Hayes, Shelly; Paskalev, Kamen; Jin Lihui; Buyyounouski, Mark K.; Ma, Charlie C.-M.; Feigenberg, Steve

    2009-01-01

    Purpose: To investigate the dosimetric impact of using 4D CT and multiphase (helical) CT images for treatment planning target definition and the daily target coverage in hypofractionated stereotactic body radiotherapy (SBRT) of lung cancer. Materials and methods: For 10 consecutive patients treated with SBRT, a set of 4D CT images and three sets of multiphase helical CT scans, taken during free-breathing, end-inspiration and end-expiration breath-hold, were obtained. Three separate planning target volumes (PTVs) were created from these image sets. A PTV 4D was created from the maximum intensity projection (MIP) reconstructed 4D images by adding a 3 mm margin to the internal target volume (ITV). A PTV 3CT was created by generating ITV from gross target volumes (GTVs) contoured from the three multiphase images. Finally, a third conventional PTV (denoted PTV conv ) was created by adding 5 mm in the axial direction and 10 mm in the longitudinal direction to the GTV (in this work, GTV = CTV = clinical target volume) generated from free-breathing helical CT scans. Treatment planning was performed based on PTV 4D (denoted as Plan-1), and the plan was adopted for PTV 3CT and PTV conv to form Plan-2 and Plan-3, respectively, by superimposing 'Plan-1' onto the helical free-breathing CT data set using modified beam apertures that conformed to either PTV 3CT or PTV conv . We first studied the impact of PTV design on treatment planning by evaluating the dosimetry of the three PTVs under the three plans, respectively. Then we examined the effect of the PTV designs on the daily target coverage by utilizing pre-treatment localization CT (CT-on-rails) images for daily GTV contouring and dose recalculation. The changes in the dose parameters of D 95 and D 99 (the dose received by 95% and 99% of the target volume, respectively), and the V p (the volume receiving the prescription dose) of the daily GTVs were compared under the three plans before and after setup error correction

  1. Establishment of an orthotopic lung cancer model in nude mice and its evaluation by spiral CT.

    Science.gov (United States)

    Liu, Xiang; Liu, Jun; Guan, Yubao; Li, Huiling; Huang, Liyan; Tang, Hailing; He, Jianxing

    2012-04-01

    To establish a simple and highly efficient orthotopic animal model of lung cancer cell line A549 and evaluate the growth pattern of intrathoracic tumors by spiral CT. A549 cells (5×10(6) mL(-1)) were suspended and inoculated into the right lung of BALB/c nude mice via intrathoracic injection. Nude mice were scanned three times each week by spiral CT after inoculation of lung cancer cell line A549. The survival time and body weight of nude mice as well as tumor invasion and metastasis were examined. Tissue was collected for subsequent histological assay after autopsia of mice. The tumor-forming rate of the orthotopic lung cancer model was 90%. The median survival time was 30.7 (range, 20-41) days. The incidence of tumor metastasis was 100%. The mean tumor diameter and the average CT value gradually increased in a time-dependent manner. The method of establishing the orthotopic lung cancer model through transplanting A549 cells into the lung of nude mice is simple and highly successful. Spiral CT can be used to evaluate intrathoracic tumor growth in nude mice vividly and dynamically.

  2. Clinical role of early dynamic FDG-PET/CT for the evaluation of renal cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Reiko; Abe, Koichiro; Sakai, Shuji [Tokyo Women' s Medical University, Department of Diagnostic Imaging and Nuclear Medicine, Tokyo (Japan); Kondo, Tsunenori; Tanabe, Kazunari [Tokyo Women' s Medical University, Department of Urology, Tokyo (Japan)

    2016-06-15

    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 < 0.001). In the WB phase, in contrast, significantly higher FDG accumulation (p < 0.001) was found in RCCs with a higher TNM stage, higher Furman grade, and the presence of V and Ly invasion in both the visual and the semiquantitative evaluations. ED and WB FDG-PET/CT is a useful tool for the evaluation of RCCs. (orig.)

  3. A navigation system for percutaneous needle interventions based on PET/CT images: design, workflow and error analysis of soft tissue and bone punctures.

    Science.gov (United States)

    Oliveira-Santos, Thiago; Klaeser, Bernd; Weitzel, Thilo; Krause, Thomas; Nolte, Lutz-Peter; Peterhans, Matthias; Weber, Stefan

    2011-01-01

    Percutaneous needle intervention based on PET/CT images is effective, but exposes the patient to unnecessary radiation due to the increased number of CT scans required. Computer assisted intervention can reduce the number of scans, but requires handling, matching and visualization of two different datasets. While one dataset is used for target definition according to metabolism, the other is used for instrument guidance according to anatomical structures. No navigation systems capable of handling such data and performing PET/CT image-based procedures while following clinically approved protocols for oncologic percutaneous interventions are available. The need for such systems is emphasized in scenarios where the target can be located in different types of tissue such as bone and soft tissue. These two tissues require different clinical protocols for puncturing and may therefore give rise to different problems during the navigated intervention. Studies comparing the performance of navigated needle interventions targeting lesions located in these two types of tissue are not often found in the literature. Hence, this paper presents an optical navigation system for percutaneous needle interventions based on PET/CT images. The system provides viewers for guiding the physician to the target with real-time visualization of PET/CT datasets, and is able to handle targets located in both bone and soft tissue. The navigation system and the required clinical workflow were designed taking into consideration clinical protocols and requirements, and the system is thus operable by a single person, even during transition to the sterile phase. Both the system and the workflow were evaluated in an initial set of experiments simulating 41 lesions (23 located in bone tissue and 18 in soft tissue) in swine cadavers. We also measured and decomposed the overall system error into distinct error sources, which allowed for the identification of particularities involved in the process as well

  4. MRI evaluation of soft tissue hydatid disease

    International Nuclear Information System (INIS)

    Garcia-Diez, A.I.; Ros Mendoza, L.H.; Villacampa, V.M.; Cozar, M.; Fuertes, M.I.

    2000-01-01

    Infestation in soft tissue by Echinococcus granulosus is not a common disease, and its diagnosis is based on clinical, laboratory data and radiological findings. The aim of our retrospective study is to give an overview of the different signs and patterns shown by MRI that can be useful in characterizing soft tissue hydatid disease. The MRI images obtained in seven patients with soft tissue and subcutaneous hydatidosis were reviewed. Typical signs of hydatidosis were multivesicular lesions with or without hypointense peripheral ring (''rim sign''). Related to the presence and absence, respectively, of viable scolices in the microscopic exam, daughter cysts were presented either as high signal intensity or low signal intensity on T2-weighted images. Low-intensity detached layers within the cyst and peripheral enhancement with gadolinium-DTPA were also presented. Atypical signs were presented in an infected muscular cyst, a subcutaneous unilocular cyst and several unilocular cysts. Knowledge of the different patterns in MRI of soft tissue hydatid disease can be useful in diagnosing this entity. We observed that the ''rim sign'' is not as common as in other locations, and in addition, MRI seems to be of assistance when evaluating the vitality of the cysts. (orig.)

  5. MRI evaluation of soft tissue hydatid disease

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Diez, A.I.; Ros Mendoza, L.H.; Villacampa, V.M.; Cozar, M.; Fuertes, M.I. [Dept. of Radiology, Hospital Miguel Servet, Zaragoza (Spain)

    2000-03-01

    Infestation in soft tissue by Echinococcus granulosus is not a common disease, and its diagnosis is based on clinical, laboratory data and radiological findings. The aim of our retrospective study is to give an overview of the different signs and patterns shown by MRI that can be useful in characterizing soft tissue hydatid disease. The MRI images obtained in seven patients with soft tissue and subcutaneous hydatidosis were reviewed. Typical signs of hydatidosis were multivesicular lesions with or without hypointense peripheral ring (''rim sign''). Related to the presence and absence, respectively, of viable scolices in the microscopic exam, daughter cysts were presented either as high signal intensity or low signal intensity on T2-weighted images. Low-intensity detached layers within the cyst and peripheral enhancement with gadolinium-DTPA were also presented. Atypical signs were presented in an infected muscular cyst, a subcutaneous unilocular cyst and several unilocular cysts. Knowledge of the different patterns in MRI of soft tissue hydatid disease can be useful in diagnosing this entity. We observed that the ''rim sign'' is not as common as in other locations, and in addition, MRI seems to be of assistance when evaluating the vitality of the cysts. (orig.)

  6. Automated segmentation of muscle and adipose tissue on CT images for human body composition analysis

    Science.gov (United States)

    Chung, Howard; Cobzas, Dana; Birdsell, Laura; Lieffers, Jessica; Baracos, Vickie

    2009-02-01

    The ability to compute body composition in cancer patients lends itself to determining the specific clinical outcomes associated with fat and lean tissue stores. For example, a wasting syndrome of advanced disease associates with shortened survival. Moreover, certain tissue compartments represent sites for drug distribution and are likely determinants of chemotherapy efficacy and toxicity. CT images are abundant, but these cannot be fully exploited unless there exist practical and fast approaches for tissue quantification. Here we propose a fully automated method for segmenting muscle, visceral and subcutaneous adipose tissues, taking the approach of shape modeling for the analysis of skeletal muscle. Muscle shape is represented using PCA encoded Free Form Deformations with respect to a mean shape. The shape model is learned from manually segmented images and used in conjunction with a tissue appearance prior. VAT and SAT are segmented based on the final deformed muscle shape. In comparing the automatic and manual methods, coefficients of variation (COV) (1 - 2%), were similar to or smaller than inter- and intra-observer COVs reported for manual segmentation.

  7. Performance evaluation of the CT component of the IRIS PET/CT preclinical tomograph

    Energy Technology Data Exchange (ETDEWEB)

    Panetta, Daniele [CNR Institute of Clinical Physiology (IFC-CNR), v. G. Moruzzi 1, I-56124 Pisa (Italy); Belcari, Nicola [Department of Physics “E. Fermi”, University of Pisa, L.go B. Pontecorvo 3, I-56127 Pisa (Italy); Tripodi, Maria [CNR Institute of Clinical Physiology (IFC-CNR), v. G. Moruzzi 1, I-56124 Pisa (Italy); Burchielli, Silvia [Fondazione CNR/Toscana “G. Monasterio” – FTGM, v. G. Moruzzi 1, I-56124 Pisa (Italy); Salvadori, Piero A. [CNR Institute of Clinical Physiology (IFC-CNR), v. G. Moruzzi 1, I-56124 Pisa (Italy); Del Guerra, Alberto [Department of Physics “E. Fermi”, University of Pisa, L.go B. Pontecorvo 3, I-56127 Pisa (Italy)

    2016-01-01

    In this paper, we evaluate the physical performance of the CT component of the IRIS scanner, a novel combined PET/CT scanner for preclinical imaging. The performance assessment is based on phantom measurement for the determination of image quality parameters (spatial resolution, linearity, geometric accuracy, contrast to noise ratio) and reproducibility in dynamic (4D) imaging. The CTDI{sub 100} has been measured free in air with a pencil ionization chamber, and the animal dose was calculated using Monte Carlo derived conversion factors taken from the literature. The spatial resolution at the highest quality protocol was 6.9 lp/mm at 10% of the MTF, using the smallest reconstruction voxel size of 58.8 μm. The accuracy of the reconstruction voxel size was within 0.1%. The linearity of the CT numbers as a function of the concentration of iodine was very good, with R{sup 2}>0.996 for all the tube voltages. The animal dose depended strongly on the scanning protocol, ranging from 158 mGy for the highest quality protocol (2 min, 80 kV) to about 12 mGy for the fastest protocol (7.3 s, 80 kV). In 4D dynamic modality, the maximum scanning rate reached was 3.1 frames per minute, using a short-scan protocol with 7.3 s of scan time per frame at the isotropic voxel size of 235 μm. The reproducibility of the system was high throughout the 10 frames acquired in dynamic modality, with a standard deviation of the CT values of all frames <8 HU and an average spatial reproducibility within 30% of the voxel size across all the field of view. Example images obtained during animal experiments are also shown.

  8. Performance evaluation of the CT component of the IRIS PET/CT preclinical tomograph

    Science.gov (United States)

    Panetta, Daniele; Belcari, Nicola; Tripodi, Maria; Burchielli, Silvia; Salvadori, Piero A.; Del Guerra, Alberto

    2016-01-01

    In this paper, we evaluate the physical performance of the CT component of the IRIS scanner, a novel combined PET/CT scanner for preclinical imaging. The performance assessment is based on phantom measurement for the determination of image quality parameters (spatial resolution, linearity, geometric accuracy, contrast to noise ratio) and reproducibility in dynamic (4D) imaging. The CTDI100 has been measured free in air with a pencil ionization chamber, and the animal dose was calculated using Monte Carlo derived conversion factors taken from the literature. The spatial resolution at the highest quality protocol was 6.9 lp/mm at 10% of the MTF, using the smallest reconstruction voxel size of 58.8 μm. The accuracy of the reconstruction voxel size was within 0.1%. The linearity of the CT numbers as a function of the concentration of iodine was very good, with R2>0.996 for all the tube voltages. The animal dose depended strongly on the scanning protocol, ranging from 158 mGy for the highest quality protocol (2 min, 80 kV) to about 12 mGy for the fastest protocol (7.3 s, 80 kV). In 4D dynamic modality, the maximum scanning rate reached was 3.1 frames per minute, using a short-scan protocol with 7.3 s of scan time per frame at the isotropic voxel size of 235 μm. The reproducibility of the system was high throughout the 10 frames acquired in dynamic modality, with a standard deviation of the CT values of all frames <8 HU and an average spatial reproducibility within 30% of the voxel size across all the field of view. Example images obtained during animal experiments are also shown.

  9. Performance evaluation of the CT component of the IRIS PET/CT preclinical tomograph

    International Nuclear Information System (INIS)

    Panetta, Daniele; Belcari, Nicola; Tripodi, Maria; Burchielli, Silvia; Salvadori, Piero A.; Del Guerra, Alberto

    2016-01-01

    In this paper, we evaluate the physical performance of the CT component of the IRIS scanner, a novel combined PET/CT scanner for preclinical imaging. The performance assessment is based on phantom measurement for the determination of image quality parameters (spatial resolution, linearity, geometric accuracy, contrast to noise ratio) and reproducibility in dynamic (4D) imaging. The CTDI_1_0_0 has been measured free in air with a pencil ionization chamber, and the animal dose was calculated using Monte Carlo derived conversion factors taken from the literature. The spatial resolution at the highest quality protocol was 6.9 lp/mm at 10% of the MTF, using the smallest reconstruction voxel size of 58.8 μm. The accuracy of the reconstruction voxel size was within 0.1%. The linearity of the CT numbers as a function of the concentration of iodine was very good, with R"2>0.996 for all the tube voltages. The animal dose depended strongly on the scanning protocol, ranging from 158 mGy for the highest quality protocol (2 min, 80 kV) to about 12 mGy for the fastest protocol (7.3 s, 80 kV). In 4D dynamic modality, the maximum scanning rate reached was 3.1 frames per minute, using a short-scan protocol with 7.3 s of scan time per frame at the isotropic voxel size of 235 μm. The reproducibility of the system was high throughout the 10 frames acquired in dynamic modality, with a standard deviation of the CT values of all frames <8 HU and an average spatial reproducibility within 30% of the voxel size across all the field of view. Example images obtained during animal experiments are also shown.

  10. Accurate tissue area measurements with considerably reduced radiation dose achieved by patient-specific CT scan parameters

    DEFF Research Database (Denmark)

    Brandberg, J.; Bergelin, E.; Sjostrom, L.

    2008-01-01

    A low-dose technique was compared with a standard diagnostic technique for measuring areas of adipose and muscle tissue and CT numbers for muscles in a body composition application. The low-dose technique was intended to keep the expected deviation in the measured area of adipose and muscle tissu...

  11. Rheumatoid arthritis of the craniocervical region: assessment and characterization of inflammatory soft tissue proliferations with unenhanced and contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Czerny, C.; Grampp, S.; Henk, C.B. [University Hospital Vienna (Austria). Dept. of Radiology; Neuhold, A. [Institute for Diagnostic Imaging, Hospital Rudolfinerhaus, Vienna (Austria); Stiskal, M. [Institute for Diagnostic Imaging, Hospital Lainz, Vienna (Austria); Smolen, J. [Department of Rheumatology, University Hospital Vienna (Austria)

    2000-09-01

    The aim of this study was to depict and characterize inflammatory soft tissue proliferations caused by rheumatoid arthritis (RA) in the craniocervical region by unenhanced and contrast-enhanced CT. Computed tomography of the craniocervical region was performed in 35 patients in the axial plane before and after the i. v. administration of contrast material. According to the densities and contrast enhancement of the inflammatory soft tissue proliferations, four groups were classified. Ancillary findings, such as a compression of the dural sac or spinal cord, erosions of the bony structures, and atlantoaxial subluxation, were also evaluated. Inflammatory soft tissue proliferations were depicted in 28 of 35 patients and could be differentiated by unenhanced and contrast-enhanced CT according to the above defined criteria: effusion in 6 patients (17 %); hypervascular pannus in 8 (23 %); hypovascular pannus in 5 (14 %); and fibrous tissue in 9 patients (26 %). A compression of the dural sac was seen in 11 (31 %) patients; 3 of these had neurological symptoms. Erosions of the odontoid process were found in 20 (57 %) patients; 16 (80 %) of these also showed erosions of the atlas. Atlantoaxial subluxation was seen in 11 (31 %) patients. Inflammatory soft tissue proliferations in the craniocervical region caused by RA can be reliably demonstrated and classified by unenhanced and contrast-enhanced CT, which can differentiate between joint effusion and various forms of pannus and depict ancillary findings. Computed tomography is an alternative method for patients unable to undergo an MRI examination. (orig.)

  12. Rheumatoid arthritis of the craniocervical region: assessment and characterization of inflammatory soft tissue proliferations with unenhanced and contrast-enhanced CT

    International Nuclear Information System (INIS)

    Czerny, C.; Grampp, S.; Henk, C.B.; Stiskal, M.; Smolen, J.

    2000-01-01

    The aim of this study was to depict and characterize inflammatory soft tissue proliferations caused by rheumatoid arthritis (RA) in the craniocervical region by unenhanced and contrast-enhanced CT. Computed tomography of the craniocervical region was performed in 35 patients in the axial plane before and after the i. v. administration of contrast material. According to the densities and contrast enhancement of the inflammatory soft tissue proliferations, four groups were classified. Ancillary findings, such as a compression of the dural sac or spinal cord, erosions of the bony structures, and atlantoaxial subluxation, were also evaluated. Inflammatory soft tissue proliferations were depicted in 28 of 35 patients and could be differentiated by unenhanced and contrast-enhanced CT according to the above defined criteria: effusion in 6 patients (17 %); hypervascular pannus in 8 (23 %); hypovascular pannus in 5 (14 %); and fibrous tissue in 9 patients (26 %). A compression of the dural sac was seen in 11 (31 %) patients; 3 of these had neurological symptoms. Erosions of the odontoid process were found in 20 (57 %) patients; 16 (80 %) of these also showed erosions of the atlas. Atlantoaxial subluxation was seen in 11 (31 %) patients. Inflammatory soft tissue proliferations in the craniocervical region caused by RA can be reliably demonstrated and classified by unenhanced and contrast-enhanced CT, which can differentiate between joint effusion and various forms of pannus and depict ancillary findings. Computed tomography is an alternative method for patients unable to undergo an MRI examination. (orig.)

  13. Perpheral bronchopleural fistula: CT evaluation in 22 patients

    International Nuclear Information System (INIS)

    Lee, Ye Ri; Kim, Min Young; Choi, Seong Hee; Kim, Eung Jo; Lee, Jin Joo; Kim, Oak

    1999-01-01

    To determine the usefulness of CT for the evaluation of peripheral bronchopleural fistulas. CT scans of 22 patients with persistent air leak, as seen on serial chest PA, and a clinical history, were retrospectively evaluated. We determined the visibility of direct communication between the lung and pleural space, and the frequency and location of this, and if direct communications were not visualized the probable cause. A bronchopleural fistula(n=13) or its probable cause(n=6) was visualized in 19 patients(86%). Direct communications between the lung and pleural space were seen in 13 patients(59%) ; there were six cases of tuberculous empyema, three of tuberculosis, two of necrotizing empyema, one of trauma, and one of postobstructive pneumonitis. In six patients, bronchiectatic change in peripheral lung adjacent to the pleural cavity was noted, and although this was seen as a probable cause of bronchopleural fistula, direct communication was invisible. Bronchopleural fistula or its probable cause was multiple in 18 of 19 patients, involving the upper and lower lobe in eight, the upper in nine, and the lower in two. CT is useful for evaluating the presence of bronchopleural fistula, and its frequency and location, and in patients in whom the fistula is not directly visualized, the cause of this

  14. CT findings of pancreatic carcinoma. Evaluation with the combined method of early enhancement CT and high dose enhancement CT

    International Nuclear Information System (INIS)

    Itoh, Shigeki; Endo, Tokiko; Isomura, Takayuki; Ishigaki, Takeo; Ikeda, Mitsuru; Senda, Kouhei.

    1995-01-01

    Computed tomographic (CT) findings of pancreatic ductal adenocarcinoma were studied with the combined method of early enhancement CT and high dose enhancement CT in 72 carcinomas. Common Findings were change in pancreatic contour, abnormal attenuation in a tumor and dilatation of the main pancreatic duct. The incidence of abnormal attenuation and dilatation of the main pancreatic duct and bile duct was constant regardless of tumor size. The finding of hypoattenuation at early enhancement CT was most useful for demonstrating a carcinoma. However, this finding was negative in ten cases, five of which showed inhomogenous hyperattenuation at high dose enhancement CT. The detection of change in pancreatic contour and dilatation of the main pancreatic duct was most frequent at high dose enhancement CT. The finding of change in pancreatic contour and/or abnormal attenuation in a tumor could be detected in 47 cases at plain CT, 66 at early enhancement CT and 65 at high dose enhancement CT. Since the four cases in which neither finding was detected by any CT method showed dilatated main pancreatic duct, there was no case without abnormal CT findings. This combined CT method will be a reliable diagnostic technique in the imaging of pancreatic carcinoma. (author)

  15. 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.)

  16. Improved correction for the tissue fraction effect in lung PET/CT imaging

    Science.gov (United States)

    Holman, Beverley F.; Cuplov, Vesna; Millner, Lynn; Hutton, Brian F.; Maher, Toby M.; Groves, Ashley M.; Thielemans, Kris

    2015-09-01

    Recently, there has been an increased interest in imaging different pulmonary disorders using PET techniques. Previous work has shown, for static PET/CT, that air content in the lung influences reconstructed image values and that it is vital to correct for this ‘tissue fraction effect’ (TFE). In this paper, we extend this work to include the blood component and also investigate the TFE in dynamic imaging. CT imaging and PET kinetic modelling are used to determine fractional air and blood voxel volumes in six patients with idiopathic pulmonary fibrosis. These values are used to illustrate best and worst case scenarios when interpreting images without correcting for the TFE. In addition, the fractional volumes were used to determine correction factors for the SUV and the kinetic parameters. These were then applied to the patient images. The kinetic parameters K1 and Ki along with the static parameter SUV were all found to be affected by the TFE with both air and blood providing a significant contribution to the errors. Without corrections, errors range from 34-80% in the best case and 29-96% in the worst case. In the patient data, without correcting for the TFE, regions of high density (fibrosis) appeared to have a higher uptake than lower density (normal appearing tissue), however this was reversed after air and blood correction. The proposed correction methods are vital for quantitative and relative accuracy. Without these corrections, images may be misinterpreted.

  17. Improved correction for the tissue fraction effect in lung PET/CT imaging

    International Nuclear Information System (INIS)

    Holman, Beverley F; Cuplov, Vesna; Millner, Lynn; Hutton, Brian F; Groves, Ashley M; Thielemans, Kris; Maher, Toby M

    2015-01-01

    Recently, there has been an increased interest in imaging different pulmonary disorders using PET techniques. Previous work has shown, for static PET/CT, that air content in the lung influences reconstructed image values and that it is vital to correct for this ‘tissue fraction effect’ (TFE). In this paper, we extend this work to include the blood component and also investigate the TFE in dynamic imaging. CT imaging and PET kinetic modelling are used to determine fractional air and blood voxel volumes in six patients with idiopathic pulmonary fibrosis. These values are used to illustrate best and worst case scenarios when interpreting images without correcting for the TFE. In addition, the fractional volumes were used to determine correction factors for the SUV and the kinetic parameters. These were then applied to the patient images. The kinetic parameters K 1 and K i along with the static parameter SUV were all found to be affected by the TFE with both air and blood providing a significant contribution to the errors. Without corrections, errors range from 34–80% in the best case and 29–96% in the worst case. In the patient data, without correcting for the TFE, regions of high density (fibrosis) appeared to have a higher uptake than lower density (normal appearing tissue), however this was reversed after air and blood correction. The proposed correction methods are vital for quantitative and relative accuracy. Without these corrections, images may be misinterpreted. (paper)

  18. The diagnostic utility of ultrasonography, CT and PET/CT for the preoperative evaluation of cervical lymph node metastasis inpapillary thyroid cancer patients

    International Nuclear Information System (INIS)

    Kim Young Sang; Lee, Tae Hyun; Park, Dong Hee

    2016-01-01

    To compare the diagnostic utility of ultrasonography (US), CT and positron emission tomography/CT (PET/CT) in the preoperative evaluation of cervical lymph node metastasis in patients with papillary thyroid carcinoma. The study population consisted of 300 patients with pathologically diagnosed papillary thyroid carcinoma after thyroidectomy and neck dissection. Preoperative US, CT, and PET/CT findings were compared with pathologic outcomes after thyroidectomy and neck dissection. Sensitivity in detecting central lymph node metastasis (US 29.9%, CT 27.9%, PET/CT 18.8%) was lower than that for lateral lymph node metastasis (US 56.3%, CT 66.2%, PET/CT 43.7%). Specificity in detecting central lymph node metastasis (US 80.6%, CT 77.7%, PET/CT 83.0%) was lower than that for lateral lymph node metastasis (US 96.8%, CT 80.6%, PET/CT 95.2%). The combination of US and CT had higher specificity (77.3%) and higher sensitivity (33.1%) than US alone. PET/CT has no significant additional benefit over the combination of US and CT. In preoperative evaluations of neck lymph node metastasis, US and CT and PET/CT are more useful in lateral lymph node areas than in central lymph node areas. The combination of US and CT has higher sensitivity than US alone

  19. The diagnostic utility of ultrasonography, CT and PET/CT for the preoperative evaluation of cervical lymph node metastasis inpapillary thyroid cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Kim Young Sang; Lee, Tae Hyun; Park, Dong Hee [Dept. of Radiology, Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    2016-08-15

    To compare the diagnostic utility of ultrasonography (US), CT and positron emission tomography/CT (PET/CT) in the preoperative evaluation of cervical lymph node metastasis in patients with papillary thyroid carcinoma. The study population consisted of 300 patients with pathologically diagnosed papillary thyroid carcinoma after thyroidectomy and neck dissection. Preoperative US, CT, and PET/CT findings were compared with pathologic outcomes after thyroidectomy and neck dissection. Sensitivity in detecting central lymph node metastasis (US 29.9%, CT 27.9%, PET/CT 18.8%) was lower than that for lateral lymph node metastasis (US 56.3%, CT 66.2%, PET/CT 43.7%). Specificity in detecting central lymph node metastasis (US 80.6%, CT 77.7%, PET/CT 83.0%) was lower than that for lateral lymph node metastasis (US 96.8%, CT 80.6%, PET/CT 95.2%). The combination of US and CT had higher specificity (77.3%) and higher sensitivity (33.1%) than US alone. PET/CT has no significant additional benefit over the combination of US and CT. In preoperative evaluations of neck lymph node metastasis, US and CT and PET/CT are more useful in lateral lymph node areas than in central lymph node areas. The combination of US and CT has higher sensitivity than US alone.

  20. The role of pneumothorax CT for the evaluation of aortic invasion by lung cancer

    International Nuclear Information System (INIS)

    Yokoi, Kohei; Mori, Kiyoshi; Miyazawa, Naoto; Magota, Seizo; Honda, Kazuyoshi; Sasagawa, Michizo

    1987-01-01

    To improve the accuracy of T3 diagnosis in lung cancer, Pneumothorax CT was carried out in four patients having diagnosis of plain CT and enhanced CT. Both plain and enhanced CT demonstrated obliteration of low density zone between tumor and the aorta in all cases. In three of four cases, Pneumothorax CT, however, demonstrated free air space where tumor was evaluated to be invaded. Remaining one presented the loss of such free air space even by Pneumothorax CT and was made the diagnosis of aortic invasion, which was confirmed by surgicopathological finding. Pneumothorax CT is useful for the diagnosis of ruling out tumor invasion to the aorta. (author)

  1. CT of laryngeal trauma

    International Nuclear Information System (INIS)

    Jeffrey, R.B.

    1986-01-01

    Computed tomography has made a significant contribution to the radiologic assessment of the injured larynx. CT is an accurate, noninvasive modality that can rapidly diagnose both soft tissue and cartilaginous injuries. CT of the larynx involves a minimal degree of patient manipulation and discomfort and can be performed in conjunction with CT evaluation of intracranial or facial injuries. Conventional radiologic studies (anteroposterior and lateral soft tissue films of the neck, tomograms, or xerograms) are capable of demonstrating some cartilaginous fractures but are of limited value in defining the extent of soft tissue injury. In the acute trauma setting, laryngography is often technically difficult to perform because of patient discomfort and inability to cooperate. Although the overall experience is somewhat limited, CT appears to overcome many of the limitations of these conventional radiologic methods. The following is a discussion of the role of CT scanning in evaluating injuries to the larynx and cervical soft tissues

  2. CT and MRI evaluation of orbital tumors: our experience

    International Nuclear Information System (INIS)

    Cabrini, Marcelo; Docampo, Jorge; Martinez, Manuel; Bruno, Claudio; Morales, Carlos

    2007-01-01

    Purpose: To show our experience in the evaluation of orbital masses on computed tomography (CT) and magnetic resonance imaging (MRI). To describe their most important findings and epidemiological features found on literature review, related to their differential diagnosis. Materials and methods: During a 48-months period of time, 26 patients (13 male, 13 female; age range, 3 to 75 years) with orbital tumors were evaluated. Seventeen patients underwent MR scans, 8 underwent CT scans, and one underwent both imaging methods. It was employed 0,5 and 1 Tesla MR scanners, and axial-helical CT scanners. Results: Benign lesions were found on 7 patients (cavernous hemangioma [n=2], meningioma [n=1], epidermoid cyst [n=1], dermoid cyst [n=1], lipoma [n=1], orbital vein deformity [n=1]). It was found lesions with undetermined behavior (optical nerve glioma [n=2]), and malignant ones were found on 17 patients (metastatic lesions [n=5], non- Hodgkin's lymphoma [n=3], hemangiopericytoma [n=2], retinoblastoma [n=2], rhabdomyosarcoma [n=2], melanoma [n=1], and lacrimal adenocarcinoma [n=1]). Conclusion: In our experience, 65.4% was malignant tumors (orbital metastasis was the most common; 19.2%). More than one-quarter was benign tumor, where cavernous hemangioma was the most frequent. (author) [es

  3. RADIOLOGICAL EVALUATION OF OBSTRUCTIVE JAUNDICE BY ULTRASOUND AND CT

    Directory of Open Access Journals (Sweden)

    Padmalatha

    2015-10-01

    Full Text Available INTRODUCTION: The goals of any radiologic procedure in obstructive Jaundice are to confirm the presence of bile duct obstruction, its location, its extent & the probable cause. It should also attempt to obtain a map of the biliary tree that will help the surgeon to det ermine the best approach to each individual case. OBJECTIVES: 1. To evaluate the role of Ultrasound and CT in patients presenting with clinical features of obstructive jaundice. 2. To evaluate the causes of obstructive jaundice by Ultrasound and CT. PATIENTS AND METHODS: The study was carried with 45 patients from January 2006 to September 2007 who were attending the surgical and Gastroenterology Departments, Govt. General Hospital, Kurnool, which is an attached hospital to Kurnool Medical College, Kurnool. O BSERVATIONS AND RESULTS: In our study, there is female predominance with male: female ratio 1: 1.6.Majority of patients are in age group of 41 - 50 years. Jaundice was the commonest presentation in all patients followed by pruritis in 72% and pain abdomen in 67% of patients. Ultrasound identified the benign cause of biliary obstruction in 79.1% cases and the malignant cause in 61.9% cases. CT identified the benign cause of biliary obstruction in 91.6% of patients and the malignant cause in 80.9% cases.

  4. Laser CT evaluation on normoxic PAGAT gel dosimeter

    International Nuclear Information System (INIS)

    Kumar, D S; Samuel, E J J; Watanabe, Y

    2013-01-01

    Optical computed tomography has been shown to be a potentially useful imaging tool for the radiation therapy physicists. In radiation therapy, researchers have used optical CT for the readout of 3D dosimeters. The purpose of this paper is to describe the initial evaluation of a newly fabricated laser CT scanner for 3D gel dosimetry which works using the first generation principle. A normoxic PAGAT (Polyacrylamide Gelatin and Tetrakis) gel is used as a dosimeter for this analysis. When a laser passes through the gel phantom, absorption and scattering of photon take place. The optical attenuation coefficient of the laser can be obtained by measuring its intensity after passing through the gel by a sensor. The scanner motion is controlled by a computer program written in Microsoft Visual C++. Reconstruction and data analysis on the irradiated gel phantom is performed by suitable algorithm using Matlab software.

  5. Optical CT evaluation on normoxic polymer gel dosimeter

    International Nuclear Information System (INIS)

    Samuel, E. James Jebaseelan

    2013-01-01

    Optical computed tomography has been shown to be a potentially useful imaging tool for the radiation therapy physicists. In radiation therapy, researchers have used optical CT for the readout of 3D dosimeters. The purpose of this paper is to explicate the initial evaluation of a newly fabricated laser CT scanner for '3D gel dosimetry' which works in the first generation principle. The normoxic PAGAT (Polyacrylamide Gelatin and Tetrakis) gel is used as a dosimeter for this analysis. When laser passes through this gel phantom, absorption and scattering of photon take place. The optical attenuation coefficient of the laser can be obtained by measuring its intensity after passing through the gel by a sensor.The scanner motion is controlled by the program written in Microsoft Visual C++. Reconstruction and data analysis on the irradiated gel phantom is performed by suitable algorithm using Matlab software. (author)

  6. Evaluation of pleural disease using MR and CT: With special reference to malignant pleural mesothelioma

    International Nuclear Information System (INIS)

    Knuuttila, A.; Kivisaari, L.; Kivisaari, A.; Palomaeki, M.; Tervahartiala, P.; Mattson, K.

    2001-01-01

    Purpose: To evaluate MR imaging and CT in differentiating malignant pleural mesothelioma from other malignancies or benign pleural disease. Material and Methods: Thirty-four patients (18 pleural mesothelioma, 9 other malignancies, 7 benign pleural diseases) were examined using enhanced CT and MR. Two radiologists reviewed the CT and two others the MR images. Comparisons were made between the diagnostic groups and the imaging methods. Results: The abnormalities commonly found in malignant disease, but significantly less frequently in benign pleural disease, were focal thickening and enhancement of inter lobar fissures. In mesothelioma, enhancement of inter lobar fissures, tumour invasion of the diaphragm, mediastinal soft tissue or chest wall, were significantly more often observed than in other malignancies and MR was the most sensitive method. In other malignancies, invasion of bony structures was a more common finding and was also better shown by MR. The contrast-enhanced T1 fat-suppressed (CET1fs) sequence detected these features better than other MR sequences. Conclusion: MR, especially the CET1fs sequence in three planes, gave more information than enhanced CT. Focal thickening and enhancement of inter lobar fissures were early abnormalities indicating malignant pleural disease. MR could be clinically useful for differentiating mesothelioma from other pleural diseases

  7. Evaluation of pleural disease using MR and CT: With special reference to malignant pleural mesothelioma

    Energy Technology Data Exchange (ETDEWEB)

    Knuuttila, A. [Helsinki Univ. Central Hospital (Finland). Dept. of Medicine; Kivisaari, L.; Kivisaari, A.; Palomaeki, M.; Tervahartiala, P. [Helsinki Univ. Central Hospital (Finland). Dept. of Radiology; Mattson, K. [Helsinki Univ. Central Hospital (Finland). Dept. of Medicine

    2001-09-01

    Purpose: To evaluate MR imaging and CT in differentiating malignant pleural mesothelioma from other malignancies or benign pleural disease. Material and Methods: Thirty-four patients (18 pleural mesothelioma, 9 other malignancies, 7 benign pleural diseases) were examined using enhanced CT and MR. Two radiologists reviewed the CT and two others the MR images. Comparisons were made between the diagnostic groups and the imaging methods. Results: The abnormalities commonly found in malignant disease, but significantly less frequently in benign pleural disease, were focal thickening and enhancement of inter lobar fissures. In mesothelioma, enhancement of inter lobar fissures, tumour invasion of the diaphragm, mediastinal soft tissue or chest wall, were significantly more often observed than in other malignancies and MR was the most sensitive method. In other malignancies, invasion of bony structures was a more common finding and was also better shown by MR. The contrast-enhanced T1 fat-suppressed (CET1fs) sequence detected these features better than other MR sequences. Conclusion: MR, especially the CET1fs sequence in three planes, gave more information than enhanced CT. Focal thickening and enhancement of inter lobar fissures were early abnormalities indicating malignant pleural disease. MR could be clinically useful for differentiating mesothelioma from other pleural diseases.

  8. A method of computerized evaluation of CT based treatment plans in external radiotherapy

    International Nuclear Information System (INIS)

    Heufelder, J.; Zink, K.; Scholz, M.; Kramer, K.D.; Welker, K.

    2003-01-01

    Selection of an optimal treatment plan requires the comparison of dose distributions and dose-volume histograms (DVH) of all plan variants calculated for the patient. Each treatment plan consists generally of 30 to 40 CT slices, making the comparison difficult and time consuming. The present study proposes an objective index that takes into account both physical and biological criteria for the evaluation of the dose distribution. The DHV-based evaluation index can be calculated according to the following four criteria: ICRU conformity (review of the differences between the dose in the planning target volume and the ICRU recommendations); mean dose and dose homogeneity of the planning target volume; the product of tumour complication probability (TCP) and normal tissue complication probability (NTCP); and finally a criterion that takes into account the dose load of non-segmented tissue portions within the CT slice. The application of the objective index is demonstrated for two different clinical cases (esophagus and breast carcinoma). During the evaluation period, the objective index showed a good correlation between the doctor's decision and the proposed objective index. Thus, the objective index is suitable for a computer-based evaluation of treatment plans. (orig.) [de

  9. Tissue decomposition from dual energy CT data for MC based dose calculation in particle therapy

    Energy Technology Data Exchange (ETDEWEB)

    Hünemohr, Nora, E-mail: n.huenemohr@dkfz.de; Greilich, Steffen [Medical Physics in Radiation Oncology, German Cancer Research Center, 69120 Heidelberg (Germany); Paganetti, Harald; Seco, Joao [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114 (United States); Jäkel, Oliver [Medical Physics in Radiation Oncology, German Cancer Research Center, 69120 Heidelberg, Germany and Department of Radiation Oncology and Radiation Therapy, University Hospital of Heidelberg, 69120 Heidelberg (Germany)

    2014-06-15

    Purpose: The authors describe a novel method of predicting mass density and elemental mass fractions of tissues from dual energy CT (DECT) data for Monte Carlo (MC) based dose planning. Methods: The relative electron density ϱ{sub e} and effective atomic number Z{sub eff} are calculated for 71 tabulated tissue compositions. For MC simulations, the mass density is derived via one linear fit in the ϱ{sub e} that covers the entire range of tissue compositions (except lung tissue). Elemental mass fractions are predicted from the ϱ{sub e} and the Z{sub eff} in combination. Since particle therapy dose planning and verification is especially sensitive to accurate material assignment, differences to the ground truth are further analyzed for mass density, I-value predictions, and stopping power ratios (SPR) for ions. Dose studies with monoenergetic proton and carbon ions in 12 tissues which showed the largest differences of single energy CT (SECT) to DECT are presented with respect to range uncertainties. The standard approach (SECT) and the new DECT approach are compared to reference Bragg peak positions. Results: Mean deviations to ground truth in mass density predictions could be reduced for soft tissue from (0.5±0.6)% (SECT) to (0.2±0.2)% with the DECT method. Maximum SPR deviations could be reduced significantly for soft tissue from 3.1% (SECT) to 0.7% (DECT) and for bone tissue from 0.8% to 0.1%. MeanI-value deviations could be reduced for soft tissue from (1.1±1.4%, SECT) to (0.4±0.3%) with the presented method. Predictions of elemental composition were improved for every element. Mean and maximum deviations from ground truth of all elemental mass fractions could be reduced by at least a half with DECT compared to SECT (except soft tissue hydrogen and nitrogen where the reduction was slightly smaller). The carbon and oxygen mass fraction predictions profit especially from the DECT information. Dose studies showed that most of the 12 selected tissues would

  10. Eye-lens bismuth shielding in paediatric head CT: artefact evaluation and reduction

    International Nuclear Information System (INIS)

    Raissaki, Maria; Perisinakis, Kostas; Damilakis, John; Gourtsoyiannis, Nicholas

    2010-01-01

    CT scans of the brain, sinuses and petrous bones performed as the initial imaging test for a variety of indications have the potential to expose the eye-lens, considered among the most radiosensitive human tissues, to a radiation dose. There are several studies in adults discussing the reduction of orbital dose resulting from the use of commercially available bismuth-impregnated latex shields during CT examinations of the head. To evaluate bismuth shielding-induced artefacts and to provide suggestions for optimal eye-lens shielding in paediatric head CT. A bismuth shield was placed over the eyelids of 60 consecutive children undergoing head CT. Images were assessed for the presence and severity of artefacts with regard to eye-shield distance and shield wrinkling. An anthropomorphic paediatric phantom and thermoluminescence dosimeters (TLDs) were used to study the effect of eye lens-to-shield distance on shielding efficiency. Shields were tolerated by 56/60 children. Artefacts were absent in 45% of scans. Artefacts on orbits, not affecting and affecting orbit evaluation were noted in 39% and 14% of scans, respectively. Diagnostically insignificant artefacts on intracranial structures were noted in 1 case (2%) with shield misplacement. Mean eye-lens-to-shield distance was 8.8 mm in scans without artefacts, and 4.3 mm and 2.2 mm in scans with unimportant and diagnostically important artefacts, respectively. Artefacts occurred in 8 out of 9 cases with shield wrinkling. Dose reduction remained unchanged for different shield-to-eye distances. Bismuth shielding-related artefacts occurring in paediatric head CT are frequent, superficial and diagnostically insignificant when brain pathology is assessed. Shields should be placed 1 cm above the eyes when orbital pathology is addressed. Shield wrinkling should be avoided. (orig.)

  11. Evaluation of normal brain CT scan in Korean

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. H.; Suh, J. H.; Park, C. Y. [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1981-06-15

    The safety of procedure combined with wealth of information have resulted in rapid acceptance of CT as a practical and reliable neurodignostic technique. To understand the alternation in tissue density and associated displacement and distortion caused by pathologic lesion in CT, it is necessary to have clear understanding of normal anatomical landmark. For the purpose of establishing normative criteria in Korean for comparative diagnosis, 500 normal CT scan without neurologic sign were studied. The brief results are follows; 1. Among many ventricular index measured for lateral ventricle, the bifrontal CVI is more sensitive and easily determined. Ventricular size increased with age, especially after 6th decade but no difference with sex. 2. Mean width of third ventricle is 5 mm ({+-} 0.3), more wider in male (male; 5.2 mm, female; 4.5 mm) and increased with age. 2. Mean width of fourth ventricle is 13 mm ({+-} 1.3), without difference in age and sex. The shape of ventricle is variable form of triangle. The position of ventricle relative to Twining's line can be determined, so ratio of distance from tuberculum sellae to center of fourth ventricle to Twining's line is between 0.46-0.52. 4. Suprasellar cistern is visible in 89.7% of scan and shape of cistern is found to be pentagonal (73.3%), hexagonal (23.0%) and tetragonal (3.7%). 5. Choroid plexus can be identified in 90% and asymmetrical in 4%. 45% of identified choroid plexus can be visible on scan without contrast enhancement, and more frequently visible in older age.

  12. Evaluation of normal brain CT scan in Koreans

    International Nuclear Information System (INIS)

    Lee, Y. H.; Suh, J. H.; Park, C. Y.

    1981-01-01

    The safety of procedure combined with wealth of information have resulted in rapid acceptance of CT as a practical and reliable neurodiagnostic technique. To understand the alternation in tissue density and associated displacement and distortion caused by pathologic lesion in CT, it is necessary to have clear understanding of normal anatomical landmark. For the purpose of establishing normartive criteria in Koreans for comparative diagnosis, 500 normal CT scan without neurologic sign were studied. The brief results are follows; 1. Among many ventricular index measured for lateral ventricle, the bifrontal CVI is more sensitive and easily determined. Ventricular size increased with age, especially after 6th decade but no difference with sex. 2. Mean width of third ventricle is 5mm( ± 0.3), more wider in male (male; 5.2mm, female; 4.5mm) and increased with age. 3. Mean width of fourth ventricle is 13mm( ± 1.3), without difference in age and sex. The shape of ventricle is variable form of triangle. The position of ventricle relative to Twining's line can be determined, so ratio of distance from tuberculum sellae to center of fourth ventricle to Twining's line is between 0.46-0.52. 4. Suprasellar cistern is visible in 89.7% of scan and shape of cistern is found to be pentagonal (73.3%), hexagonal (23.0%) and tetragonal (3.7%). 5. Choroid plexus can be identified in 90% and asymetrical in 4%. 45% of identified choroid plexus can be visible on scan without contrast enhancement, and more frequently visible in older age

  13. Evaluation of normal brain CT scan in Korean

    International Nuclear Information System (INIS)

    Lee, Y. H.; Suh, J. H.; Park, C. Y.

    1981-01-01

    The safety of procedure combined with wealth of information have resulted in rapid acceptance of CT as a practical and reliable neurodignostic technique. To understand the alternation in tissue density and associated displacement and distortion caused by pathologic lesion in CT, it is necessary to have clear understanding of normal anatomical landmark. For the purpose of establishing normative criteria in Korean for comparative diagnosis, 500 normal CT scan without neurologic sign were studied. The brief results are follows; 1. Among many ventricular index measured for lateral ventricle, the bifrontal CVI is more sensitive and easily determined. Ventricular size increased with age, especially after 6th decade but no difference with sex. 2. Mean width of third ventricle is 5 mm (± 0.3), more wider in male (male; 5.2 mm, female; 4.5 mm) and increased with age. 2. Mean width of fourth ventricle is 13 mm (± 1.3), without difference in age and sex. The shape of ventricle is variable form of triangle. The position of ventricle relative to Twining's line can be determined, so ratio of distance from tuberculum sellae to center of fourth ventricle to Twining's line is between 0.46-0.52. 4. Suprasellar cistern is visible in 89.7% of scan and shape of cistern is found to be pentagonal (73.3%), hexagonal (23.0%) and tetragonal (3.7%). 5. Choroid plexus can be identified in 90% and asymmetrical in 4%. 45% of identified choroid plexus can be visible on scan without contrast enhancement, and more frequently visible in older age

  14. Effects of acupuncture evaluated by EEG topogram and positron CT

    International Nuclear Information System (INIS)

    Mori, Kazu; Yano, Tadashi

    1990-01-01

    Electroencephalographic (EEG) topography and positron CT were performed in 30 subjects to examine the effects of needle stimulation on the function of the central nervous system. Needle stimulation was administered to IC 10 Shousanli-IC 4 Hoku, bilateral VF 12 Head-Wanku, and G 36 Tsusanli-LP 6 Shanyinchiao at a frequency of 2 Hz. Changes in EEG power were observed in all cortical regions, especially in the area from the frontal to the occipital lobe. The subjects could be divided into two types - the type in which the power increased only in the α zone, and the type in which the power increased in both θ and α zones. Positron CT revealed that 'de-qi' (the acupuncture feeling) transiently invigorates the paleocortex and the neocortex, and exerts influences on a wide range of cranial nervous cells via the A 10 nerve. Variation in regional cerebral blood flow induced by the electric needle stimulation was 15-20 ml/100 g brain tissue/min on average. Comfortable stimulation by the needle method is effective in eliminating disharmony between the neocortex and the paleocortex, regulating the function of the autonomic nerves, and stabilizing the spirit. (N.K.)

  15. Effects of acupuncture evaluated by EEG topogram and positron CT

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Kazu; Yano, Tadashi (Meiji Coll. of Oriental Medicine, Hiyoshi, Kyoto (Japan))

    1990-02-01

    Electroencephalographic (EEG) topography and positron CT were performed in 30 subjects to examine the effects of needle stimulation on the function of the central nervous system. Needle stimulation was administered to IC{sub 10} Shousanli-IC{sub 4} Hoku, bilateral VF{sub 12} Head-Wanku, and G{sub 36} Tsusanli-LP{sub 6} Shanyinchiao at a frequency of 2 Hz. Changes in EEG power were observed in all cortical regions, especially in the area from the frontal to the occipital lobe. The subjects could be divided into two types - the type in which the power increased only in the {alpha} zone, and the type in which the power increased in both {theta} and {alpha} zones. Positron CT revealed that 'de-qi' (the acupuncture feeling) transiently invigorates the paleocortex and the neocortex, and exerts influences on a wide range of cranial nervous cells via the A{sub 10} nerve. Variation in regional cerebral blood flow induced by the electric needle stimulation was 15-20 ml/100 g brain tissue/min on average. Comfortable stimulation by the needle method is effective in eliminating disharmony between the neocortex and the paleocortex, regulating the function of the autonomic nerves, and stabilizing the spirit. (N.K.).

  16. Retrospective evaluation of acute appendicitis incorrectly diagnosed on CT

    International Nuclear Information System (INIS)

    Kim, Tae Hoon; Kim, Hyun Cheol

    2006-01-01

    The purpose of our study was to retrospectively evaluate the CT images of patients suffering with surgically proven appendicitis to determine the causes of missed diagnoses. We reviewed the pathology reports of the patients with surgically proven appendicitis from two hospitals during a 3-year period. Thirty-seven such cases with a misdiagnosis were identified and they served as our misdiagnosed group (17 females and 20 males, mean age: 58 years, age range 15-68 years). These were cases that were misdiagnosed on preoperative abdominal CT. All 57 patients in the control group (30 females and 27 males, mean age: 44 years, age range: 21-78 years) had undergone laparotomy for acute appendicitis and they had been correctly diagnosed preoperatively on CT. Two abdominal radiologists evaluated the following items from all 94 CT examinations: 1) an abnormal appendix, 2) periappendiceal fat inflammation, 3) pericecal extraluminal fluid, 4) pericecal extraluminal air, 5) appendicolith, 6) cecal wall thickening, 7) small bowel dilatation, and 8) the pericecal fat content. Statistical analysis was performed using a Chi-squared test and Fisher's exact test. Any abnormal appendix was not visualized, even retrospectively, in 27 (73%) of the 37 patients from the misdiagnosed group, whereas it was not visualized in 13 (23%) of the 57 patients in the control group (ρ = 0.001). Of the patients who had been misdiagnosed, inflammation of the pericecal fat was observed in 21 patients (57%) as compared to 50 (88%) patients in the control group (ρ =0.001). Pericecal fluid and air were noted in 15 (41%) and 9 (24%) patients, respectively, in the misdiagnosed group and in 19 (33%) and 14 (25%) patients, respectively, in the control group, (ρ = 0.477 and ρ =0.901, respectively). Appendicolith was found in 3 (8%) misdiagnosed subjects and in 10 (18%) of the controls (ρ = 0.001). Focal cecal wall thickening was noted in 14 (38%) misdiagnosed patients and in 28 (49%) control patients (

  17. Evaluating applicability of metal artifact reduction algorithm for head and neck radiation treatment planning CT

    International Nuclear Information System (INIS)

    Son, Sang Jun; Park, Jang Pil; Kim, Min Jeong; Yoo, Suk Hyun

    2014-01-01

    The purpose of this study is evaluation for the applicability of O-MAR(Metal artifact Reduction for Orthopedic Implants)(ver. 3.6.0, Philips, Netherlands) in head and neck radiation treatment planning CT with metal artifact created by dental implant. All of the in this study's CT images were scanned by Brilliance Big Bore CT(Philips, Netherlands) at 120 kVp, 2 mm sliced and Metal artifact reduced by O-MAR. To compare the original and reconstructed CT images worked on RTPS(Eclipse ver 10.0.42, Varian, USA). In order to test the basic performance of the O-MAR, The phantom was made to create metal artifact by dental implant and other phantoms used for without artifact images. To measure a difference of HU in with artifact images and without artifact images, homogeneous phantom and inhomogeneous phantoms were used with cerrobend rods. Each of images were compared a difference of HU in ROIs. And also, 1 case of patient's original CT image applied O-MAR and density corrected CT were evaluated for dose distributions with SNC Patient(Sun Nuclear Co., USA). In cases of head and neck phantom, the difference of dose distribution is appeared 99.8% gamma passing rate(criteria 2 mm / 2%) between original and CT images applied O-MAR. And 98.5% appeared in patient case, among original CT, O-MAR and density corrected CT. The difference of total dose distribution is less than 2% that appeared both phantom and patient case study. Though the dose deviations are little, there are still matters to discuss that the dose deviations are concentrated so locally. In this study, The quality of all images applied O-MAR was improved. Unexpectedly, Increase of max. HU was founded in air cavity of the O-MAR images compare to cavity of the original images and wrong corrections were appeared, too. The result of study assuming restrained case of O-MAR adapted to near skin and low density area, it appeared image distortion and artifact correction simultaneously. In O-MAR CT, air cavity area

  18. PET/CT versus bone marrow biopsy in the initial evaluation of bone marrow infiltration in various pediatric malignancies.

    Science.gov (United States)

    Zapata, Claudia P; Cuglievan, Branko; Zapata, Catalina M; Olavarrieta, Raquel; Raskin, Scott; Desai, Kavita; De Angulo, Guillermo

    2018-02-01

    Accurate staging is essential in the prognosis and management of pediatric malignancies. Current protocols require screening for marrow infiltration with bone marrow biopsy (BMB) as the gold standard. Positron emission tomography-computed tomography (PET-CT) is commonly used to complete the staging process and can also be used to evaluate marrow infiltration. To compare PET-CT and BMB in the initial evaluation of bone marrow infiltration in pediatric cancers. We retrospectively reviewed new cases of EWS, rhabdomyosarcoma, neuroblastoma, and lymphoma diagnosed between January 2009 and October 2014. Each case had undergone both PET-CT and BMB within 4 weeks without treatment in the interval between screening modalities. We reviewed 69 cases. Bone marrow infiltration was demonstrated in 34 cases by PET-CT and in 18 cases by BMB. The sensitivity and negative predictive value of PET-CT were both 100%. Interestingly, the cases in which infiltration was not detected on BMB had an abnormal marrow signal on PET-CT focal or distant to iliac crest. PET-CT has a high sensitivity when assessing marrow infiltration in pediatric malignancies. Advances in radiologic modalities may obviate the use of invasive, painful, and costly procedures like BMB. Furthermore, biopsy results are limited by insufficient tissue or the degree of marrow infiltration (diffuse vs. focal disease). PET-CT can improve the precision of biopsy when used as a guiding tool. This study proposes the use of PET-CT as first-line screening for bone marrow infiltration to improve the accuracy of staging in new diagnoses. © 2017 Wiley Periodicals, Inc.

  19. Spectral CT evaluation of interstitial brachytherapy in pancreatic carcinoma xenografts: preliminary animal experience

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Shudong [Jiangsu University, Department of Radiology, The Affiliated Renmin Hospital, Zhenjiang, Jiangsu (China); Shanghai Jiao tong University, School of Medicine, Department of Radiology, Ruijin Hospital, Shanghai (China); Huang, Wei; Song, Qi; Lin, Xiaozhu; Wang, Zhongmin; Chen, Kemin [Shanghai Jiao tong University, School of Medicine, Department of Radiology, Ruijin Hospital, Shanghai (China); Chen, Yerong [Jiangsu University, Department of Radiology, The Affiliated Renmin Hospital, Zhenjiang, Jiangsu (China)

    2014-09-15

    We sought to evaluate the capability of spectral CT to detect the therapeutic response to {sup 125}I interstitial brachytherapy in a pancreatic carcinoma xenograft nude mouse model. Twenty mice bearing SWl990 human pancreatic cancer cell xenografts were randomly separated into two groups: experimental (n = 10; 1.0 mCi) and control (n = 10; 0 mCi). After a two-week treatment, spectral CT was performed. Contrast-to-noise ratio (CNR) and iodine concentration (IC) in the lesions were measured and normalized to the muscle tissue, and nIC CD31 immunohistochemistry was used to measure microvessel density (MVD). The relationships between the nIC and MVD of the tumours were analysed. The nIC of the experimental group was significantly lower than that of the control group during the multiphase examination. A significant difference in the MVD was observed between the two groups (P <0.001). The nIC values of the three-phase scans have a certain positive correlation with MVD (r = 0.57, p < 0.0001; r = 0.48, p = 0.002; r = 0.63, p = 0.0017 in the 10, 25, and 60 s phase, respectively). Spectral CT can be a useful non-invasive imaging modality in evaluating the therapeutic effect of {sup 125}I interstitial brachytherapy to a pancreatic carcinoma. (orig.)

  20. Borrmann type IV adenocarcinoma versus gastric lymphoma : spiral CT evaluation

    International Nuclear Information System (INIS)

    Seo, Bo Kyoung; Kim, Yun Hwan; Shin, Kue Hee; Hong, Suk Joo; Kim, Hong Weon; Park, Cheol Min; Chung, Kyoo Byung; Cho, Hyun Deuk

    1999-01-01

    To distinguish the spiral CT findings of Borrmann type IV adenocarcinoma from those of gastric lymphoma with diffuse gastric wall thickening. We retrospectively reviewed the spiral CT scans of 30 patients with Borrmann type IV adenocarcinoma and nine with gastric lymphoma with diffuse gastric wall thickening. In all patients the respective condition was pathologically confirmed by gastrectomy. CT scanning was performed after peroral administration of 500-700ml of water. A total of 120-140 ml bolus of nonionic contrast material was administered intravenously at a flow rate of 3 ml/sec and two-phase images were obtained at 35-45 sec(early phase) and 180 sec(delayed phase) after the start of bolus injection. Spiral CT was performed with 10mm collimation, 10mm/sec table feed and 10mm reconstruction. We evaluated the degree and homogeneity of enhancement of thickened entire gastric wall, and the enhancement pattern of gastric inner layer, as seen on early-phase CT scans. On early and delayed views, the thickness of gastric wall and the presence of perigastric fat infiltration were determined. The enhancement patterns of gastric inner layer were classified as either continuous or discontinuous thick enhancement, thin enhancement, or nonenhancement. The thickness of gastric wall was 1.2-3.5cm(mean 2.2cm) in cases of adenocarcinoma and 1.2-7.6cm(mean 4cm) in lymphoma. Perigastric fat infiltration was seen in 24 patients with adenocarcinoma(80%) and four with lymphoma(44%). In those with adenocarcinoma, the degree of enhancement of entire gastric wall was hyperdense in fifteen patients(50%) and isointense in eleven (37%). Seven patients with lymphoma(78%)showed hypodensity. In those with adenocarcinoma, continuous thick enhancement of gastric inner layer was seen in 18 patients(60%) and discontinuous thick enhancement in nine(30%). In lymphoma cases, no thick enhancement was observed. Thin enhancement of gastric inner layer was demonstrated in three patients with

  1. Evaluation of abdominal CT in the initial treatment of abdominal trauma

    International Nuclear Information System (INIS)

    Watanabe, Shinsuke; Ishii, Takashi; Kuwata, Katsuya; Yoneyama, Chihiro; Kitamura, Kazuya; Sasaki, Yoshifumi; Kamachi, Masahiro; Nishiguchi, Hiroyasu.

    1986-01-01

    During the last four years 102 patients with abdominal trauma were examined by CT for preoperative evaluation in our hospital. In 35 patients (34 %), the CT scans revealed no abnormal findings. They were all managed conservatively except for one case of perforated small bowel. In 67 patients (66 %) CT revealed evidences of substantial abdominal or retroperitoneal trauma. In 30 of them CT findings were confirmed by surgery. Hepatic injury is usually easily recognized by CT. CT is also useful for the detection of renal or splenic injuries. The majority of those parenchymatous organ injuries were successfully managed with conservative therapy, despite apparent traumatic lesions revealed by CT. Repeat CT scans is proved to be very useful to follow the changes of these traumatic lesions. In conclusion, application of abdominal CT is extremely useful for the initial decision making in treatment of patients with abdominal trauma and for the follow-up observation of injured lesions. (author)

  2. Application of single- and dual-energy CT brain tissue segmentation to PET monitoring of proton therapy

    Science.gov (United States)

    Berndt, Bianca; Landry, Guillaume; Schwarz, Florian; Tessonnier, Thomas; Kamp, Florian; Dedes, George; Thieke, Christian; Würl, Matthias; Kurz, Christopher; Ganswindt, Ute; Verhaegen, Frank; Debus, Jürgen; Belka, Claus; Sommer, Wieland; Reiser, Maximilian; Bauer, Julia; Parodi, Katia

    2017-03-01

    The purpose of this work was to evaluate the ability of single and dual energy computed tomography (SECT, DECT) to estimate tissue composition and density for usage in Monte Carlo (MC) simulations of irradiation induced β + activity distributions. This was done to assess the impact on positron emission tomography (PET) range verification in proton therapy. A DECT-based brain tissue segmentation method was developed for white matter (WM), grey matter (GM) and cerebrospinal fluid (CSF). The elemental composition of reference tissues was assigned to closest CT numbers in DECT space (DECTdist). The method was also applied to SECT data (SECTdist). In a validation experiment, the proton irradiation induced PET activity of three brain equivalent solutions (BES) was compared to simulations based on different tissue segmentations. Five patients scanned with a dual source DECT scanner were analyzed to compare the different segmentation methods. A single magnetic resonance (MR) scan was used for comparison with an established segmentation toolkit. Additionally, one patient with SECT and post-treatment PET scans was investigated. For BES, DECTdist and SECTdist reduced differences to the reference simulation by up to 62% when compared to the conventional stoichiometric segmentation (SECTSchneider). In comparison to MR brain segmentation, Dice similarity coefficients for WM, GM and CSF were 0.61, 0.67 and 0.66 for DECTdist and 0.54, 0.41 and 0.66 for SECTdist. MC simulations of PET treatment verification in patients showed important differences between DECTdist/SECTdist and SECTSchneider for patients with large CSF areas within the treatment field but not in WM and GM. Differences could be misinterpreted as PET derived range shifts of up to 4 mm. DECTdist and SECTdist yielded comparable activity distributions, and comparison of SECTdist to a measured patient PET scan showed improved agreement when compared to SECTSchneider. The agreement between predicted and measured PET

  3. Quantitative measurement of radiofrequency volumetric tissue reduction by multidetector CT in patients with inferior turbinate hypertrophy.

    Science.gov (United States)

    Bahadir, Osman; Kosucu, Polat

    2012-12-01

    To objectively assess the efficacy of radiofrequency thermal ablation of inferior turbinate hypertrophy. Thirty-five patients with nasal obstruction secondary to inferior turbinate hypertrophy were prospectively enrolled. Radiofrequency energy was delivered to four sites in each inferior turbinate. Patients were evaluated before and 8 weeks after intervention. Subjective evaluation of nasal obstruction was performed using a visual analogue scale (VAS), and objective evaluation of the turbinate volume reduction was calculated using multidetector CT. Volumetric measurements of the preoperative inferior turbinate were compared with postoperative values on both sides. The great majority of patients (91.4%) exhibited subjective postoperative improvement. Mean obstruction (VAS) improved significantly from 7.45±1.48 to 3.54±1.96. Significant turbinate volume reduction was achieved by the surgery on both right and left sides [(preoperative vs. postoperative, right: 6.55±1.62cm(3) vs. 5.10±1.47cm(3), (PRadiofrequency is a safe and effective surgical procedure in reducing turbinate volume in patients with inferior turbinate hypertrophy. Multidetector CT is an objective method of assessment in detecting radiofrequency turbinate volume reduction. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  4. Hemoretroperitoneum associated with liver bare area injuries: CT evaluation

    International Nuclear Information System (INIS)

    Miele, V.; Adami, L.; Andreoli, C.; De Cicco, M.L.; David, V.

    2002-01-01

    In hepatic injury restricted to the postero-superior region of segment VII (bare area), hemoperitoneum may be absent and this condition may be associated with hemoretroperitoneum. The aim of this paper is to present the association between bare area injuries and hemoretroperitoneum evaluated by CT. The CT examinations of 32 patients with blunt liver trauma were reviewed and the number and location of lesions were evaluated. Right lobe involvement was identified, focusing on the bare area lesions. The presence of hemoperitoneum and hemoretroperitoneum were determined. In the 32 patients 44 parenchymal lesions were detected. Segment VII was involved in 16 cases: 5 patients presented an intraparenchymal lesion, 11 patients a lesion emerging to the liver surface. In 8 cases the lesion was localized in the bare area. In the 16 patients presenting a segment-VII lesion, hemoperitoneum was detected in 3 cases, hemoretroperitoneum in 4 cases, and both conditions in 4 cases. A traumatic hepatic lesion may be associated with hemoretroperitoneum rather than hemoperitoneum. This justifies the absence of clinical signals of peritoneal irritation; the negativity of both US scan and peritoneal lavage may cause an inappropriate therapeutic management. Computed tomography yields both the detection of the parenchymal damage and the correct localization of the intraperitoneal and retroperitoneal hemorrhage. (orig.)

  5. Hemoretroperitoneum associated with liver bare area injuries: CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Miele, V.; Adami, L. [Department of Radiology, Camillo Hospital, Rome (Italy); Andreoli, C.; De Cicco, M.L.; David, V. [I Chair of Radiology, University ' ' La Sapienza' ' , Rome (Italy)

    2002-04-01

    In hepatic injury restricted to the postero-superior region of segment VII (bare area), hemoperitoneum may be absent and this condition may be associated with hemoretroperitoneum. The aim of this paper is to present the association between bare area injuries and hemoretroperitoneum evaluated by CT. The CT examinations of 32 patients with blunt liver trauma were reviewed and the number and location of lesions were evaluated. Right lobe involvement was identified, focusing on the bare area lesions. The presence of hemoperitoneum and hemoretroperitoneum were determined. In the 32 patients 44 parenchymal lesions were detected. Segment VII was involved in 16 cases: 5 patients presented an intraparenchymal lesion, 11 patients a lesion emerging to the liver surface. In 8 cases the lesion was localized in the bare area. In the 16 patients presenting a segment-VII lesion, hemoperitoneum was detected in 3 cases, hemoretroperitoneum in 4 cases, and both conditions in 4 cases. A traumatic hepatic lesion may be associated with hemoretroperitoneum rather than hemoperitoneum. This justifies the absence of clinical signals of peritoneal irritation; the negativity of both US scan and peritoneal lavage may cause an inappropriate therapeutic management. Computed tomography yields both the detection of the parenchymal damage and the correct localization of the intraperitoneal and retroperitoneal hemorrhage. (orig.)

  6. Thallium scintigraphy used in the evaluation of soft tissue sarcoma

    International Nuclear Information System (INIS)

    Pilloni, A.; Brooks, R.

    1998-01-01

    Full text: The use of thallium scintigraphy in tumour localisation is a promising diagnostic modality. Thallium has a good affinity for numerous tumour types including sarcomas. Its properties as a potassium analogue result in active uptake via the sodium- potassium ATP-ase pump enabling its use in evaluating tumour extent, viability, staging, localisation and treatment. This case illustrates the role of thallium in tumour staging. A 67-year-old woman with a fibrous histiocytoma resected from the right foot four months previously presented with pain in the ribs, lower back and feet. A bone scan was performed to assess the possibility of metastatic disease. Several abnormal foci were seen on the bone scan suggestive of metastatic disease. A thallium scan was performed to confirm the bone scan result after a subsequent CT scan showed no evidence of this extensive disease. Static images of the whole body were acquired on an Elscinct 400AG 20 minutes post i.v. injection of 3.5 mCi of thallium. Focal areas of increased thallium uptake were seen in the 11th rib posteriorly and in the left sacroiliac region corresponding with sites on the bone scan suggesting metastases. However, an extensive area of uptake was also observed in the right inguinal region which had no corresponding abnormalities in the bone study. This was thought to be tumour metastasis in an inguinal Iymph node, which was retrospectively confirmed on an earlier CT scan of the pelvis. This study demonstrates the usefulness of thallium in the detection of soft tissue tumours and metastases. Thallium also exhibits potential in the assessment of tumour extent and viability pre- and post-treatment. This potential needs to be explored further in patient management

  7. SU-E-J-275: Review - Computerized PET/CT Image Analysis in the Evaluation of Tumor Response to Therapy

    International Nuclear Information System (INIS)

    Lu, W; Wang, J; Zhang, H

    2015-01-01

    Purpose: To review the literature in using computerized PET/CT image analysis for the evaluation of tumor response to therapy. Methods: We reviewed and summarized more than 100 papers that used computerized image analysis techniques for the evaluation of tumor response with PET/CT. This review mainly covered four aspects: image registration, tumor segmentation, image feature extraction, and response evaluation. Results: Although rigid image registration is straightforward, it has been shown to achieve good alignment between baseline and evaluation scans. Deformable image registration has been shown to improve the alignment when complex deformable distortions occur due to tumor shrinkage, weight loss or gain, and motion. Many semi-automatic tumor segmentation methods have been developed on PET. A comparative study revealed benefits of high levels of user interaction with simultaneous visualization of CT images and PET gradients. On CT, semi-automatic methods have been developed for only tumors that show marked difference in CT attenuation between the tumor and the surrounding normal tissues. Quite a few multi-modality segmentation methods have been shown to improve accuracy compared to single-modality algorithms. Advanced PET image features considering spatial information, such as tumor volume, tumor shape, total glycolytic volume, histogram distance, and texture features have been found more informative than the traditional SUVmax for the prediction of tumor response. Advanced CT features, including volumetric, attenuation, morphologic, structure, and texture descriptors, have also been found advantage over the traditional RECIST and WHO criteria in certain tumor types. Predictive models based on machine learning technique have been constructed for correlating selected image features to response. These models showed improved performance compared to current methods using cutoff value of a single measurement for tumor response. Conclusion: This review showed that

  8. SU-E-J-275: Review - Computerized PET/CT Image Analysis in the Evaluation of Tumor Response to Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lu, W; Wang, J; Zhang, H [University of Maryland School of Medicine, Baltimore, MD (United States)

    2015-06-15

    Purpose: To review the literature in using computerized PET/CT image analysis for the evaluation of tumor response to therapy. Methods: We reviewed and summarized more than 100 papers that used computerized image analysis techniques for the evaluation of tumor response with PET/CT. This review mainly covered four aspects: image registration, tumor segmentation, image feature extraction, and response evaluation. Results: Although rigid image registration is straightforward, it has been shown to achieve good alignment between baseline and evaluation scans. Deformable image registration has been shown to improve the alignment when complex deformable distortions occur due to tumor shrinkage, weight loss or gain, and motion. Many semi-automatic tumor segmentation methods have been developed on PET. A comparative study revealed benefits of high levels of user interaction with simultaneous visualization of CT images and PET gradients. On CT, semi-automatic methods have been developed for only tumors that show marked difference in CT attenuation between the tumor and the surrounding normal tissues. Quite a few multi-modality segmentation methods have been shown to improve accuracy compared to single-modality algorithms. Advanced PET image features considering spatial information, such as tumor volume, tumor shape, total glycolytic volume, histogram distance, and texture features have been found more informative than the traditional SUVmax for the prediction of tumor response. Advanced CT features, including volumetric, attenuation, morphologic, structure, and texture descriptors, have also been found advantage over the traditional RECIST and WHO criteria in certain tumor types. Predictive models based on machine learning technique have been constructed for correlating selected image features to response. These models showed improved performance compared to current methods using cutoff value of a single measurement for tumor response. Conclusion: This review showed that

  9. TU-AB-BRC-03: Accurate Tissue Characterization for Monte Carlo Dose Calculation Using Dual-and Multi-Energy CT Data

    Energy Technology Data Exchange (ETDEWEB)

    Lalonde, A; Bouchard, H [University of Montreal, Montreal, Qc (Canada)

    2016-06-15

    Purpose: To develop a general method for human tissue characterization with dual-and multi-energy CT and evaluate its performance in determining elemental compositions and the associated proton stopping power relative to water (SPR) and photon mass absorption coefficients (EAC). Methods: Principal component analysis is used to extract an optimal basis of virtual materials from a reference dataset of tissues. These principal components (PC) are used to perform two-material decomposition using simulated DECT data. The elemental mass fraction and the electron density in each tissue is retrieved by measuring the fraction of each PC. A stoichiometric calibration method is adapted to the technique to make it suitable for clinical use. The present approach is compared with two others: parametrization and three-material decomposition using the water-lipid-protein (WLP) triplet. Results: Monte Carlo simulations using TOPAS for four reference tissues shows that characterizing them with only two PC is enough to get a submillimetric precision on proton range prediction. Based on the simulated DECT data of 43 references tissues, the proposed method is in agreement with theoretical values of protons SPR and low-kV EAC with a RMS error of 0.11% and 0.35%, respectively. In comparison, parametrization and WLP respectively yield RMS errors of 0.13% and 0.29% on SPR, and 2.72% and 2.19% on EAC. Furthermore, the proposed approach shows potential applications for spectral CT. Using five PC and five energy bins reduces the SPR RMS error to 0.03%. Conclusion: The proposed method shows good performance in determining elemental compositions from DECT data and physical quantities relevant to radiotherapy dose calculation and generally shows better accuracy and unbiased results compared to reference methods. The proposed method is particularly suitable for Monte Carlo calculations and shows promise in using more than two energies to characterize human tissue with CT.

  10. TU-AB-BRC-03: Accurate Tissue Characterization for Monte Carlo Dose Calculation Using Dual-and Multi-Energy CT Data

    International Nuclear Information System (INIS)

    Lalonde, A; Bouchard, H

    2016-01-01

    Purpose: To develop a general method for human tissue characterization with dual-and multi-energy CT and evaluate its performance in determining elemental compositions and the associated proton stopping power relative to water (SPR) and photon mass absorption coefficients (EAC). Methods: Principal component analysis is used to extract an optimal basis of virtual materials from a reference dataset of tissues. These principal components (PC) are used to perform two-material decomposition using simulated DECT data. The elemental mass fraction and the electron density in each tissue is retrieved by measuring the fraction of each PC. A stoichiometric calibration method is adapted to the technique to make it suitable for clinical use. The present approach is compared with two others: parametrization and three-material decomposition using the water-lipid-protein (WLP) triplet. Results: Monte Carlo simulations using TOPAS for four reference tissues shows that characterizing them with only two PC is enough to get a submillimetric precision on proton range prediction. Based on the simulated DECT data of 43 references tissues, the proposed method is in agreement with theoretical values of protons SPR and low-kV EAC with a RMS error of 0.11% and 0.35%, respectively. In comparison, parametrization and WLP respectively yield RMS errors of 0.13% and 0.29% on SPR, and 2.72% and 2.19% on EAC. Furthermore, the proposed approach shows potential applications for spectral CT. Using five PC and five energy bins reduces the SPR RMS error to 0.03%. Conclusion: The proposed method shows good performance in determining elemental compositions from DECT data and physical quantities relevant to radiotherapy dose calculation and generally shows better accuracy and unbiased results compared to reference methods. The proposed method is particularly suitable for Monte Carlo calculations and shows promise in using more than two energies to characterize human tissue with CT.

  11. Comparative analysis of multi-slice spiral CT and positron emission tomography-CT in evaluation of axillary lymph nodes in breast cancer patients

    International Nuclear Information System (INIS)

    Sun Xianchang; Zhang Ruyi; Liu Qingwei; Zhao Suhong; Zu Degui; Li Xin

    2008-01-01

    Objective: To evaluate and compare spiral CT and positron emission tomography-CT (PET-CT) in characterization of of axillary lymph nodes in breast cancer patients. Methods: Forty patients with pathologically proven breast cancer underwent contrast-enhanced spiral CT of the breast and axilla, 13 of them also underwent PET-CT examination. One hundred and fifty-eight axillary lymph nodes were found in the 40 patients through contrast enhanced spiral CT, while 57 lymph nodes were found in the 13 patients through PET-CT. Three radiologists rated the lymph nodes found in CT images on a five-point scale. If the score was equal to or greater than 3, it was defined as positive (metastatic), otherwise negative. Visual observation and semiquantitative analysis were used to classify lymph nodes in PET-CT images. The results of spiral CT observation and PET-CT observation of lymph nodes were compared with pathological results. The relative value of CT and PET-CT was analyzed. Exact probability statistics were employed. Results: One hundred and fifty eight lymph nodes of 40 patients were detected by spiral CT, 91 of them were diagnosed as positive and 67 as negative Among the lymph nodes found in spiral CT, 99 were positive and 59 were negative pathologicall. A total of 57 lymph nodes were found by PET-CT. Thirty-nine of them were defined as positive and 18 as negative. Among the lymph nodes found in PET-CT, 39 were positive and 18 were negative pathologically. The sensitivity, specificity, accuracy, positive and negative predictive values in CT prediction in axillary lymph nodes metastases were 88.89%, 94.91%, 91.14%, 96.70%, and 83.58%, respectively. The sensitivity, specificity, accuracy, positive and negative predictive values in PET-CT prediction in axillary lymph nodes metastases were 97.44%, 94.44%, 96.49%, 97.44%, and 94.44%, respectively. PET-CT had no significant difference with spiral CT in sensitivity, accuracy, positive and negative predictive values for detection

  12. Normal mediastinal and hilar lymph nodes evaluated by 5 mm slice bolus injection CT scan

    International Nuclear Information System (INIS)

    Yamamoto, Takako; Tsukada, Hiroshi; Koizumi, Naoya; Akita, Shinichi; Oda, Junichi; Sakai, Kunio

    1995-01-01

    We evaluated the number and size of normal mediastinal and hilar lymph nodes by 5 mm slice bolus injection CT (12 patients), compared with 10 mm slice CT (12 patients). More lymph nodes were clearly demonstrated by 5 mm slice CT than by 10 mm slice CT. Especially left-sided tracheobronchial (no.4), subaortic (no.5), subcarinal (no.7) and hilar lymph nodes were clearly visible. We concluded 5 mm slice bolus injection CT was useful to evaluate mediastinal and hilar lymph nodes. (author)

  13. Highly sensitive detection of the soft tissues based on refraction contrast by in-plane diffraction-enhanced imaging CT

    International Nuclear Information System (INIS)

    Yuasa, Tetsuya; Hashimoto, Eiko; Maksimenko, Anton; Sugiyama, Hiroshi; Arai, Yoshinori; Shimao, Daisuke; Ichihara, Shu; Ando, Masami

    2008-01-01

    We discuss the recently proposed computed tomography (CT) technique based on refractive effects for biomedical use, which reconstructs the in-plane refractive-index gradient vector field in a cross-sectional plane of interest by detecting the angular deviation of the beam, refracted by a sample, from the incident beam, using the diffraction-enhanced imaging (DEI) method. The CT has advantages for delineating biological weakly absorbing soft tissues over the conventional absorption-contrast CT because of the use of phase sensitive detection. The paper aims to define the imaging scheme rigidly and to demonstrate its efficacy for non-destructive measurement of biomedical soft-tissue samples without imaging agent. We first describe the imaging principle of in-plane DEI-CT from the physico-mathematical viewpoints in detail, and investigate what physical quantities are extracted from the reconstructed images. Then, we introduce the imaging system using the synchrotron radiation as a light source, constructed at beamline BL-14B in KEK, Japan. Finally, we demonstrate the advantage of the refraction-based image for non-destructive analysis of biological sample by investigating the image of human breast cancer tumors obtained using the imaging system. Here, the refraction- and the apparent absorption-based images obtained simultaneously by the in-plane DEI-CT are compared. Also, the conventional absorption-based image obtained using micro-computed tomography (μCT) imaging system is compared with them. Thereby, it is shown that the refraction contrast much more sensitively delineates the soft tissues than the absorption contrast. In addition, the radiologic-histologic correlation study not only validates the efficacy for imaging soft tissues, but also produces the potential that the pathological inspection for the breast cancer tumors may be feasible non-destructively

  14. What is the complementary role of ultrasound evaluation in the diagnosis of acute appendicitis after CT?

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Kyung Mi [Department of Radiology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Lee, Kwanseop [Department of Radiology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of)], E-mail: kwanseop@hallym.or.kr; Kim, Min-Jeong; Yoon, Hoi Soo; Jeon, Eui Yong; Koh, Sung Hye [Department of Radiology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Min, Kwangseon [Department of Pathology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Choi, Dongil [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (Korea, Republic of)

    2010-04-15

    The objective of our study was to estimate the complementary role of ultrasound evaluation in the diagnosis of acute appendicitis after abdominoplevic CT. A total of 104 patients initially underwent abdominopelvic CT before appendix US due to acute abdominal pain. All CT examinations were evaluated retrospectively for the presence of acute appendicitis. The findings of appendix on CT were classified into five categories (definite appendicitis, probably appendicitis, equivocal CT findings for diagnosis of appendicitis, probably not appendicitis, and normal looking appendix). Appendix US images and their radiologic reports were also evaluated retrospectively. Then, CT and US findings were correlated with clinical or pathologic diagnosis. Three all patients with definite appendicitis initially on CT again showed US findings of appendicitis. In the 32 patients of probably appendicitis on CT, US showed normal looking appendix in seven patients (21.8%, 7 of 32) who improved with medical treatment and discharged. In the 16 patients of equivocal CT findings for diagnosis of appendicitis, US showed appendicitis in seven patients (43.8%, 7 of 16) and normal looking appendix in nine patients. In the 12 patients of probably not appendicitis on CT, US showed acute appendicitis in two patients (16.7%, 2 of 12). In the 41 patients of normal looking appendix on CT, US showed acute appendicitis in five patients (12.2%, 5 of 41). US reevaluation enables us to avoid misdiagnosis of appendicitis on CT and improve diagnostic accuracy of acute appendicitis.

  15. High resolution micro-CT scanning as an innovative tool for evaluation of the surgical positioning of cochlear implant electrodes.

    Science.gov (United States)

    Postnov, A; Zarowski, A; De Clerck, N; Vanpoucke, F; Offeciers, F E; Van Dyck, D; Peeters, S

    2006-05-01

    X-ray microtomography (micro-CT) is a new technique allowing for visualization of the internal structure of opaque specimens with a quasi-histological quality. Among multiple potential applications, the use of this technique in otology is very promising. Micro-CT appears to be ideally suited for in vitro visualization of the inner ear tissues as well as for evaluation of the electrode damage and/or surgical insertion trauma during implantation of the cochlear implant electrodes. This technique can greatly aid in design and development of new cochlear implant electrodes and is applicable for temporal bone studies. The main advantage of micro-CT is the practically artefact-free preparation of the samples and the possibility of evaluation of the interesting parameters along the whole insertion depth of the electrode. This paper presents the results of the first application of micro-CT for visualization of the inner ear structures in human temporal bones and for evaluation of the surgical positioning of the cochlear implant electrodes relative to the intracochlear soft tissues.

  16. Supratentorial primary intra-axial tumors in children. MR and CT evaluation

    International Nuclear Information System (INIS)

    Higano, S.; Takahashi, S.; Kurihara, N.; Singh, L.N.; Yamada, S.; Ishii, K.; Matsumoto, K.; Shirane, R.; Katakura, R.

    1997-01-01

    Purpose: To evaluate the MR and CT features of pediatric supratentorial intra-axial tumors with respect to different diagnosis and the role of each investigation modality. Material and Methods: MR and CT findings in 40 children with 12 types of pathologically proven histological tumors were reviewed. Results: The location of tumors might be one clue to differential diagnosis. In our material, cysts (60%), calcifications (45%), and intratumoral hemorrhages (27%) were found in the tumors. Characteristic features noted in some lesions included: peritumoral hemosiderin deposition in cavernous angiomas; intratumoral flow void in a choroid plexus carcinoma and in glioblastomas; and hemicerebral atrophy in germinomas. A comparison between malignant and benign tumors showed perifocal edema and a mass effect to be signifcantly more common in malignant lesions. Homogeneous enhancement suggested a benign tumor and an inhomogeneous pattern represented malignancy, while the lack of obvious enhancement did not always suggest benignity. Intratumoral calcium deposition was a not uncommon finding in malignant tumors. Conclusion: In most cases, the exact diagnosis should be made hy histological examination but it is important for treatment planning that the appropriate depiction of tumor extension and tissue characterization be made by MR and CT. (orig.)

  17. Measurement of Trabecular Bone Parameters in Porcine Vertebral Bodies Using Multidetector CT: Evaluation of Reproducibility of 3-Dimensional CT Histomorphometry

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sung Hwan; Goo, Jin Mo [Dept. of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); Moon Kyung Chul [Dept. of Pathology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); An, Sang Bu [Dept. of radiology, National Cancer Center, Goyang (Korea, Republic of); Kim, Kwang Gi [Dept. of Biomedical Engineering, Division of Basic and Applied Sciences, National Cancer Center, Goyang (Korea, Republic of)

    2011-05-15

    To evaluate the reproducibility of 3-dimensional histomorphometry for the microarchitecture analysis of trabecular bone parameters using multidetector computed tomography (MDCT). Thirty-six specimens from porcine vertebral bodies were imaged five times with a 64- detector row MDCT system using the same scan protocols. Locations of the specimens were nearly identical through the scans. Three-dimensional structural parameters of trabecular bone were derived from the five data sets using image analyzing software. The features measured by the analysis programs were trabecular bone volume, trabecular bone volume/tissue volume, trabecular thickness, trabecular separation, trabecular number, trabecular bone pattern factor, structural model index. The structural trabecular parameters showed excellent reproducibility through repeated scanning. Intraclass correlation coefficients of all seven structural parameters were in the range of 0.998 to 1.000. Coefficients of variation of the six structural parameters, excluding structural model index, were not over 1.6%. The measurement of the trabecular structural parameters using multidetector CT and three-dimensional histomophometry analysis program was validated and showed excellent reproducibility. This method could be used as a noninvasive and easily available test in a clinical setting.

  18. CT evaluation of sigmoid plate dehiscence causing pulsatile tinnitus

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Pengfei; Lv, Han; Dong, Cheng; Wang, Zhenchang [Capital Medical University, Department of Radiology, Beijing Friendship Hospital, Beijing (China); Niu, Yantao; Xian, Junfang [Capital Medical University, Department of Radiology, Beijing Tongren Hospital, Beijing (China)

    2016-01-15

    To evaluate the characteristics of sigmoid plate dehiscence (SPD) causing pulsatile tinnitus (PT) on CT arteriography and venography (CTA + V). Thirty PT patients treated successfully with SPD reconstruction were enrolled. Sixty asymptomatic patients were matched. The location, extent, number of SPD cases and concomitant signs, including venous outflow dominance, transverse sinus stenosis, high jugular bulb, temporal bone pneumatization, height of pituitary gland and pituitary fossa, abnormal mastoid emissary vein, were detected and compared using CTA + V. More than one SPD was found on the symptomatic side in 13/30 PT patients (43.3 %). The upper segment of the sigmoid plate was involved in 29/44 SPDs in the vertical direction (65.9 %); the lateral wall was involved in 38/44 SPDs in the horizontal direction (86.4 %). Singular SPD was detected in 3/60 asymptomatic patients (1.67 ± 0.35 mm{sup 2}), less so in PT patients (7.97 ± 5.17 mm{sup 2}). Compared with the control group, ipsilateral venous outflow dominance, high jugular bulb and bilateral transverse sinus stenosis were more common in the PT group, together with deeper pituitary fossa and flatter pituitary glands. SPD causing PT has characteristic CT findings. It may be generated by vascular or intracranial pressure abnormalities and act as a common key to triggering PT's perception. (orig.)

  19. Intracranial aneurysms: evaluation in 200 patients with spiral CT angiography

    International Nuclear Information System (INIS)

    Young, N.; Kingston, R.J.; Markson, G.; Dorsch, N.W.C.; McMahon, J.

    2001-01-01

    The goal of this study was to assess the usefulness of spiral CT angiography (CTA) with three- dimensional reconstructions in defining intracranial aneurysms, particularly around the Circle of Willis. Two hundred consecutive patients with angiographic and/or surgical correlation were studied between 1993 and 1998, with CTA performed on a GE HiSpeed unit and Windows workstation. The following clinical situations were evaluated: conventional CT suspicion of an aneurysm; follow-up of treated aneurysm remnants or of untreated aneurysms; subarachnoid haemorrhage (SAH) and negative angiography; family or past aneurysm history; and for improved definition of aneurysm anatomy. Spiral CTA detected 140 of 144 aneurysms, and an overall sensitivity of 97%, including 30 of 32 aneurysms 3 mm or less in size. In 38 patients with SAH and negative angiography, CTA found six of the seven aneurysms finally diagnosed. There was no significant artefact in 17 of 23 patients (74%) with clips. The specificity of CTA was 86% with 8 false-positive cases. Spiral CTA is very useful in demonstrating intracranial aneurysms. (orig.)

  20. CT evaluation of sigmoid plate dehiscence causing pulsatile tinnitus

    International Nuclear Information System (INIS)

    Zhao, Pengfei; Lv, Han; Dong, Cheng; Wang, Zhenchang; Niu, Yantao; Xian, Junfang

    2016-01-01

    To evaluate the characteristics of sigmoid plate dehiscence (SPD) causing pulsatile tinnitus (PT) on CT arteriography and venography (CTA + V). Thirty PT patients treated successfully with SPD reconstruction were enrolled. Sixty asymptomatic patients were matched. The location, extent, number of SPD cases and concomitant signs, including venous outflow dominance, transverse sinus stenosis, high jugular bulb, temporal bone pneumatization, height of pituitary gland and pituitary fossa, abnormal mastoid emissary vein, were detected and compared using CTA + V. More than one SPD was found on the symptomatic side in 13/30 PT patients (43.3 %). The upper segment of the sigmoid plate was involved in 29/44 SPDs in the vertical direction (65.9 %); the lateral wall was involved in 38/44 SPDs in the horizontal direction (86.4 %). Singular SPD was detected in 3/60 asymptomatic patients (1.67 ± 0.35 mm 2 ), less so in PT patients (7.97 ± 5.17 mm 2 ). Compared with the control group, ipsilateral venous outflow dominance, high jugular bulb and bilateral transverse sinus stenosis were more common in the PT group, together with deeper pituitary fossa and flatter pituitary glands. SPD causing PT has characteristic CT findings. It may be generated by vascular or intracranial pressure abnormalities and act as a common key to triggering PT's perception. (orig.)

  1. Contrast medium enhancement of soft tissues and brain in CT examinations of dogs

    International Nuclear Information System (INIS)

    Pavlicek, M.

    2000-11-01

    CT is an x-ray based method which shows less contrast for soft tissue as has been known from radiography. Therefore, it is necessary to use intravenously administered iodine contrast media to detect and localize tumors, fistulas or other pathologic lesions. Usually contrast medium is administered manually which yields random patterns of media distribution due to varying application pressure during varying administration time, therefore enhancement of parenchymous organs could not be used to the optimum extent. The use of an automatic injection pump guarantees the necessary constancy during the examination procedure to undoubtedly detect pathologic enhancement of organs in the CT-image as known from human medicine. The standards which are expected of the injection pump and the contrast media are: a good contrast enhancement, a good accumulation in the examined organs, an accumulation, which lasts long enough during the diagnostic phase, and a rapid excretion without side effects. Because of the short scan time of the modern CT-scanner, the best contrast enhancement can be administered by a short bolus injection, which can be applied by the automatic injection pump with a defined flow and a defined quantity of contrast media. This guarantees a good enhancement in the chosen region for the duration of the scan. The main aim of this study is to find a standardized flow and quantity of contrast media for defined regions and organs considering the speed of the scanner. In a subsequent step, the existing scan-protocols are then updated using the newly found information. This study showed, that CT examination of the head and brain in middle-sized dogs can be administered with a flow of 0.5 ml/s and a dose of 2 ml of contrast medium per kg weight. The contrast enhancement of the brain is caused by the enhancement of the vessels, the parenchym is free of contrast media - brain shows a low increase of density. Only if the blood-brain-barrier is destroyed, it is possible that

  2. Contrast medium enhancement of soft tissues and brain in CT examinations of dogs

    International Nuclear Information System (INIS)

    Pavlicek, M.

    2000-11-01

    CT is a x-ray based method which shows less contrast for soft tissue as has been known from radiography. Therefore, it is necessary to use intravenously administered iodine contrast media to detect and localize tumors, fistulas or other pathologic lesions. Usually contrast medium is administered manually which yields random patterns of media distribution due to varying application pressure during varying administration time, therefore enhancement of parenchymous organs could not be used to the optimum extent. The use of an automatic injection pump guarantees the necessary constancy during the examination procedure to undoubtedly detect pathologic enhancement of organs in the CT-image as known from human medicine. The standards which are expected of the injection pump and the contrast media are: a good contrast enhancement, a good accumulation in the examined organs, an accumulation, which lasts long enough during the diagnostic phase, and a rapid excretion without side effects. Because of the short scan time of the modern CT-scanner, the best contrast enhancement can be administered by a short bolus injection, which can be applied by the automatic injection pump with a defined flow and a defined quantity of contrast media. This guarantees a good enhancement in the chosen region for the duration of the scan. The main aim of this study is to find a standardized flow and quantity of contrast media for defined regions and organs considering the speed of the scanner. In a subsequent step, the existing scan-protocols are then updated using the newly found information. This study showed, that CT examination of the head and brain in middle-sized dogs can be administered with a flow of 0.5 ml/s and a dose of 2 ml of contrast medium per kg weight. The contrast enhancement of the brain is caused by the enhancement of the vessels, the parenchym is free of contrast media - brain shows a low increase of density. Only if the blood-brain-barrier is destroyed, it is possible that

  3. Performance evaluation of the General Electric eXplore CT 120 micro-CT using the vmCT phantom

    Energy Technology Data Exchange (ETDEWEB)

    Bahri, M.A., E-mail: M.Bahri@ulg.ac.be [ULg-Liege University, Cyclotron Research Centre, Liege, Bat. 30, Allee du 6 aout, 8 (Belgium); Warnock, G.; Plenevaux, A. [ULg-Liege University, Cyclotron Research Centre, Liege, Bat. 30, Allee du 6 aout, 8 (Belgium); Choquet, P.; Constantinesco, A. [Biophysique et Medecine Nucleaire, Hopitaux universitaires de Strasbourg, Strasbourg (France); Salmon, E.; Luxen, A. [ULg-Liege University, Cyclotron Research Centre, Liege, Bat. 30, Allee du 6 aout, 8 (Belgium); Seret, A. [ULg-Liege University, Cyclotron Research Centre, Liege, Bat. 30, Allee du 6 aout, 8 (Belgium); ULg-Liege University, Experimental Medical Imaging, Liege (Belgium)

    2011-08-21

    The eXplore CT 120 is the latest generation micro-CT from General Electric. It is equipped with a high-power tube and a flat-panel detector. It allows high resolution and high contrast fast CT scanning of small animals. The aim of this study was to compare the performance of the eXplore CT 120 with that of the eXplore Ultra, its predecessor for which the methodology using the vmCT phantom has already been described . The phantom was imaged using typical a rat (fast scan or F) or mouse (in vivo bone scan or H) scanning protocols. With the slanted edge method, a 10% modulation transfer function (MTF) was observed at 4.4 (F) and 3.9-4.4 (H) mm{sup -1} corresponding to 114 {mu}m resolution. A fairly larger MTF was obtained by the coil method with the MTF for the thinnest coil (3.3 mm{sup -1}) equal to 0.32 (F) and 0.34 (H). The geometric accuracy was better than 0.3%. There was a highly linear (R{sup 2}>0.999) relationship between measured and expected CT numbers for both the CT number accuracy and linearity sections of the phantom. A cupping effect was clearly seen on the uniform slices and the uniformity-to-noise ratio ranged from 0.52 (F) to 0.89 (H). The air CT number depended on the amount of polycarbonate surrounding the area where it was measured; a difference as high as approximately 200 HU was observed. This hindered the calibration of this scanner in HU. This is likely due to the absence of corrections for beam hardening and scatter in the reconstruction software. However in view of the high linearity of the system, the implementation of these corrections would allow a good quality calibration of the scanner in HU. In conclusion, the eXplore CT 120 achieved a better spatial resolution than the eXplore Ultra (based on previously reported specifications) and future software developments will include beam hardening and scatter corrections that will make the new generation CT scanner even more promising.

  4. Clinical implications of determination of safe surgical margins by using a combination of CT and 18FDG-positron emission tomography in soft tissue sarcoma

    Directory of Open Access Journals (Sweden)

    Yoshioka Takako

    2011-07-01

    Full Text Available Abstract Background To determine safe surgical margins for soft tissue sarcoma, it is essential to perform a general evaluation of the extent of tumor, responses to auxiliary therapy, and other factors preoperatively using multiple types of diagnostic imaging. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT is a tool for diagnostic imaging that has recently spread rapidly in clinical use. At present, the roles played by FDG-PET/CT in determination of margins for surgical resection of sarcoma are unclear. The present study was undertaken to explore the roles of FDG-PET/CT in determination of surgical margins for soft tissue sarcoma and to examine whether PET can serve as a standard means for setting the margins of surgical resection during reduced surgery. Methods The study involved 7 patients with sarcoma who underwent surgery in our department and in whom evaluation with FDG-PET/CT was possible. Sarcoma was histologically rated as MFH in 6 cases and leiomyosarcoma in 1 case. In all cases, sarcoma was superficial (T1a or T2a. The tumor border was defined by contrast-enhanced MRI, and SUVs were measured at intervals of 1 cm over a 5-cm long area from the tumor border. Mapping of viable tumor cells was carried out on whole-mount sections of resected tissue, and SUVs were compared with histopathological findings. Results Preoperative maximum SUVs (SUV-max of the tumor averaged 11.7 (range: 3.8-22.1. Mean SUV-max was 2.2 (range: 0.3-3.8 at 1 cm from the tumor border, 1.1 (0.85-1.47 at 2 cm, 0.83 (0.65-1.15 at 3 cm, 0.7 (0.42-0.95 at 4 cm, and 0.64 (0.45-0.82 at 5 cm. When resected tissue was mapped, tumor cells were absent in the areas where SUV-max was below 1.0. Conclusions Our findings suggest that a safe surgical margin free of viable tumor cells can be ensured if the SUV cut-off level is set at 1.0. FDG-PET/CT is promising as a diagnostic imaging technique for setting of safe minimal margins for surgical

  5. CT versus FDG-PET/CT response evaluation in patients with metastatic colorectal cancer treated with irinotecan and cetuximab

    DEFF Research Database (Denmark)

    Skougaard, Kristin; Johannesen, Helle Hjorth; Nielsen, Dorte

    2014-01-01

    included in a phase II trial and treated with cetuximab and irinotecan every second week. They underwent FDG-PET/CT examination at baseline and after every fourth treatment cycle. Response evaluation was performed prospectively according to Response Evaluation Criteria in Solid Tumors (RECIST 1...

  6. Preoperative evaluation of renal anatomy and renal masses with helical CT, 3D-CT and 3D-CT angiography.

    Science.gov (United States)

    Toprak, Uğur; Erdoğan, Aysun; Gülbay, Mutlu; Karademir, Mehmet Alp; Paşaoğlu, Eşref; Akar, Okkeş Emrah

    2005-03-01

    The aim of this prospective study was to determine the efficacy of three-dimensional computed tomography (3D-CT) and three-dimensional computed tomographic angiography (3D-CTA) that were reconstructed by using the axial images of the multiphasic helical CT in the preoperative evaluation of renal masses and demonstration of renal anatomy. Twenty patients that were suspected of having renal masses upon initial physical examination and ultrasonographic evaluation were examined through multiphasic helical CT. Two authors executed CT evaluations. Axial images were first examined and then used to reconstruct 3D-CT and 3D- CTA images. Number, location and size of the renal masses and other findings were noted. Renal vascularization and relationships of the renal masses with the neighboring renal structures were further investigated with 3D-CT and 3D-CTA images. Out of 20 patients, 13 had histopathologically proven renal cell carcinoma. The diagnoses of the remaining seven patients were xanthogranulomatous pyelonephritis, abscess, simple cyst, infected cyst, angiomyolipoma, oncocytoma and arteriovenous fistula. In the renal cell carcinoma group, 3 patients had stage I, 7 patients had stage II, and 3 patients had stage III disease. Sizes of renal cell carcinoma masses were between 23 mm to 60 mm (mean, 36 mm). Vascular invasion was shown in 2 renal cell carcinoma patients. Collecting system invasion was identified in 11 of 13 renal cell patients. These radiologic findings were confirmed with surgical specimens. Three-dimensional CT and 3D-CTA are non-invasive, effective imaging techniques for the preoperative evaluation of renal masses.

  7. Treatment response evaluation with 18F-FDG PET/CT and 18F-NaF PET/CT in multiple myeloma patients undergoing high-dose chemotherapy and autologous stem cell transplantation.

    Science.gov (United States)

    Sachpekidis, Christos; Hillengass, J; Goldschmidt, H; Wagner, B; Haberkorn, U; Kopka, K; Dimitrakopoulou-Strauss, A

    2017-01-01

    The aim of this study was to assess the combined use of the radiotracers 18 F-FDG and 18 F-NaF in treatment response evaluation of a group of multiple myeloma (MM) patients undergoing high-dose chemotherapy (HDT) followed by autologous stem cell transplantation (ASCT) by means of static (whole-body) and dynamic PET/CT (dPET/CT). Thirty-four patients with primary, previously untreated MM scheduled for treatment with HDT followed by ASCT were enrolled in the study. All patients underwent PET/CT scanning with 18 F-FDG and 18 F-NaF before and after therapy. Treatment response by means of PET/CT was assessed according to the European Organization for Research and Treatment of Cancer (EORTC) 1999 criteria. The evaluation of dPET/CT studies was based on qualitative evaluation, semi-quantitative (SUV) calculation, and quantitative analysis based on two-tissue compartment modelling and a non-compartmental approach leading to the extraction of fractal dimension (FD). An analysis was possible in 29 patients: three with clinical complete response (CR) and 26 with non-CR (13 patients near complete response-nCR, four patients very good partial response-VGPR, nine patients partial response-PR). After treatment, 18 F-FDG PET/CT was negative in 14/29 patients and positive in 15/29 patients, showing a sensitivity of 57.5 % and a specificity of 100 %. According to the EORTC 1999 criteria, 18 F-FDG PET/CT-based treatment response revealed CR in 14 patients ( 18 F-FDG PET/CT CR), PR in 11 patients ( 18 F-FDG PET/CT PR) and progressive disease in four patients ( 18 F-FDG PET/CT PD). In terms of 18 F-NaF PET/CT, 4/29 patients (13.8 %) had a negative baseline scan, thus failed to depict MM. Regarding the patients for which a direct lesion-to-lesion comparison was feasible, 18 F-NaF PET/CT depicted 56 of the 129 18 F-FDG positive lesions (43 %). Follow-up 18 F-NaF PET/CT showed persistence of 81.5 % of the baseline 18 F-NaF positive MM lesions after treatment, despite the fact that 64

  8. Study on the hard tissue changes in osteomyelitis of the jaws using CT image

    International Nuclear Information System (INIS)

    An, Chang Hyeon; Choi, Bo Ram; Huh, Kyung Hoe; Yi, Won Jin; Lee, Sam Sun; Choi, Soon Chul

    2009-01-01

    To assess the clinical findings and hard tissue changes of osteomyelitis of the jaws using computed tomographic (CT) image analysis. We reviewed and interpreted the CT images of 163 patients (64 males and 99 females, age range from 10 to 87 years) who visited the Seoul National University Dental Hospital from April 23, 2006 to December 31, 2008 and were diagnosed as osteomyelitis of the jaws through clinical, radiologic, and histopathologic examination. Each CT findings was investigated for frequency, correlation with age and gender. Of the 163 patients, 31 (19.0%) were affected on the maxilla, 135 (82.8%) were affected on the mandible, and 3 (1.8%) were affected on the both jaws simultaneously. The mean age of the patients who were affected on the maxilla was 61.0 years and that of the patients who were affected on the mandible was 56.2 years. On the maxilla, the most frequent site of disease was the posterior area (83.9%) and on the mandible, mandibular body (83.0%), followed by angle (48.1%), ramus (38.5%), condyle (13.3%), incisal area (9.6%), and coronoid process (3.0%). Among the 31 maxillary osteomyelitis, defect in the trabecular bone was observed in 28 (90.3%), osteosclerosis 20 (64.5%), defect in the cortical bone 27 (87.1%), sequestrum 17 (54.8%), and periosteal reaction 2 (6.5%). Among the 135 mandibular osteomyelitis, defect in the trabecular bone was observed in 100 (74.1%), osteosclerosis 104 (77.0%), defect in the cortical bone 116 (85.9%), sequestrum 36 (26.7%), and periosteal reaction 67 (49.6%). Of our cases, the maxillary osteomyelitis was visibly observed more frequently in females than males. The incidence is the highest in seventies (28.8%) and the lowest in teens (3.1%). The osteomyelitis of the jaws was observed more frequently in males than females before the age of 50, and observed more frequently in females after the age of 50. The most noticeable point was that the sequestrum was observed more often on maxillary osteomyelitis and the

  9. Evaluation of bone viability in patients after girdlestone arthroplasty: comparison of bone SPECT/CT and MRI

    International Nuclear Information System (INIS)

    Diederichs, G.; Collettini, F.; Hamm, B.; Makowski, M.R.; Hoppe, P.; Brenner, W.; Wassilew, G.

    2017-01-01

    To test the diagnostic performance of bone SPECT/CT and MRI for the evaluation of bone viability in patients after girdlestone-arthroplasty with histopathology used as gold standard. In this cross-sectional study, patients after girdlestone-arthroplasty were imaged with single-photon-emission-computed-tomography/computed-tomography (SPECT/CT) bone-scans using 99mTc-DPD. Additionally, 1.5 T MRI was performed with turbo-inversion-recovery-magnitude (TIRM), contrast-enhanced T1-fat sat (FS) and T1-mapping. All imaging was performed within 24 h prior to revision total-hip-arthroplasty in patients with a girdlestone-arthroplasty. In each patient, four standardized bone-tissue-biopsies (14 patients) were taken intraoperatively at the remaining acetabulum superior/inferior and trochanter major/minor. Histopathological evaluation of bone samples regarding bone viability was used as gold standard. A total of 56 bone-segments were analysed and classified as vital (n = 39) or nonvital (n = 17) by histopathology. Mineral/late-phase SPECT/CT showed a high sensitivity (90%) and specificity (94%) to distinguish viable and nonviable bone tissue. TIRM (sensitivity 87%, specificity 88%) and contrast-enhanced T1-FS (sensitivity 90%, specificity 88%) also achieved a high sensitivity and specificity. T1-mapping achieved the lowest values (sensitivity 82%, specificity 82%). False positive results in SPECT/CT and MRI resulted from small bone fragments close to metal artefacts. Both bone SPECT/CT and MRI allow a reliable differentiation between viable and nonviable bone tissue in patients after girdlestone arthroplasty. The findings of this study could also be relevant for the evaluation of bone viability in the context of avascular bone necrosis. (orig.)

  10. Evaluation of bone viability in patients after girdlestone arthroplasty: comparison of bone SPECT/CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Diederichs, G.; Collettini, F.; Hamm, B.; Makowski, M.R. [Department of Radiology, Berlin (Germany); Hoppe, P.; Brenner, W. [Department of Nuclear Medicine, Berlin (Germany); Wassilew, G. [Department of Orthopedic Surgery, Berlin (Germany)

    2017-09-15

    To test the diagnostic performance of bone SPECT/CT and MRI for the evaluation of bone viability in patients after girdlestone-arthroplasty with histopathology used as gold standard. In this cross-sectional study, patients after girdlestone-arthroplasty were imaged with single-photon-emission-computed-tomography/computed-tomography (SPECT/CT) bone-scans using 99mTc-DPD. Additionally, 1.5 T MRI was performed with turbo-inversion-recovery-magnitude (TIRM), contrast-enhanced T1-fat sat (FS) and T1-mapping. All imaging was performed within 24 h prior to revision total-hip-arthroplasty in patients with a girdlestone-arthroplasty. In each patient, four standardized bone-tissue-biopsies (14 patients) were taken intraoperatively at the remaining acetabulum superior/inferior and trochanter major/minor. Histopathological evaluation of bone samples regarding bone viability was used as gold standard. A total of 56 bone-segments were analysed and classified as vital (n = 39) or nonvital (n = 17) by histopathology. Mineral/late-phase SPECT/CT showed a high sensitivity (90%) and specificity (94%) to distinguish viable and nonviable bone tissue. TIRM (sensitivity 87%, specificity 88%) and contrast-enhanced T1-FS (sensitivity 90%, specificity 88%) also achieved a high sensitivity and specificity. T1-mapping achieved the lowest values (sensitivity 82%, specificity 82%). False positive results in SPECT/CT and MRI resulted from small bone fragments close to metal artefacts. Both bone SPECT/CT and MRI allow a reliable differentiation between viable and nonviable bone tissue in patients after girdlestone arthroplasty. The findings of this study could also be relevant for the evaluation of bone viability in the context of avascular bone necrosis. (orig.)

  11. Helical CT in the primary trauma evaluation of the cervical spine: an evidence-based approach

    Energy Technology Data Exchange (ETDEWEB)

    Blackmore, C.C. [Washington Univ., Seattle, WA (United States). Dept. of Radiology; Center for Cost and Outcomes Research, Univ. of Washington, Seattle (United States); Dept. of Radiology, Harborview Medical Center, Seattle, WA (United States); Mann, F.A. [Washington Univ., Seattle, WA (United States). Dept. of Radiology; Harborview Injury Prevention and Research Center, University of Washington, Seattle (United States); Wilson, A.J. [Washington Univ., Seattle, WA (United States). Dept. of Radiology

    2000-11-01

    This review provides a summary of the cost-effectiveness, clinical utility, performance, and interpretation of screening helical cervical spine CT for trauma patients. Recent evidence supports the use of helical CT as a cost-effective method for screening the cervical spine in high-risk trauma patients. Screening cervical spine CT can be performed at the time of head CT to lower the cost of the evaluation, and when all short- and long-term costs are considered, CT may actually save money when compared with traditional radiographic screening. In addition to having higher sensitivity and specificity for cervical spine injury, CT screening also allows more rapid radiological clearance of the cervical spine than radiography. Patients who are involved in high-energy trauma, who sustain head injury, or who have neurological deficits are candidates for CT screening. Screening with CT may enhance detection of other potentially important injuries of the cervical region. (orig.)

  12. {sup 18}F-FDG PET/CT evaluation of children and young adults with suspected spinal fusion hardware infection

    Energy Technology Data Exchange (ETDEWEB)

    Bagrosky, Brian M. [University of Colorado School of Medicine, Department of Pediatric Radiology, Children' s Hospital Colorado, 12123 E. 16th Ave., Box 125, Aurora, CO (United States); University of Colorado School of Medicine, Department of Radiology, Division of Nuclear Medicine, Aurora, CO (United States); Hayes, Kari L.; Fenton, Laura Z. [University of Colorado School of Medicine, Department of Pediatric Radiology, Children' s Hospital Colorado, 12123 E. 16th Ave., Box 125, Aurora, CO (United States); Koo, Phillip J. [University of Colorado School of Medicine, Department of Radiology, Division of Nuclear Medicine, Aurora, CO (United States)

    2013-08-15

    Evaluation of the child with spinal fusion hardware and concern for infection is challenging because of hardware artifact with standard imaging (CT and MRI) and difficult physical examination. Studies using {sup 18}F-FDG PET/CT combine the benefit of functional imaging with anatomical localization. To discuss a case series of children and young adults with spinal fusion hardware and clinical concern for hardware infection. These people underwent FDG PET/CT imaging to determine the site of infection. We performed a retrospective review of whole-body FDG PET/CT scans at a tertiary children's hospital from December 2009 to January 2012 in children and young adults with spinal hardware and suspected hardware infection. The PET/CT scan findings were correlated with pertinent clinical information including laboratory values of inflammatory markers, postoperative notes and pathology results to evaluate the diagnostic accuracy of FDG PET/CT. An exempt status for this retrospective review was approved by the Institution Review Board. Twenty-five FDG PET/CT scans were performed in 20 patients. Spinal fusion hardware infection was confirmed surgically and pathologically in six patients. The most common FDG PET/CT finding in patients with hardware infection was increased FDG uptake in the soft tissue and bone immediately adjacent to the posterior spinal fusion rods at multiple contiguous vertebral levels. Noninfectious hardware complications were diagnosed in ten patients and proved surgically in four. Alternative sources of infection were diagnosed by FDG PET/CT in seven patients (five with pneumonia, one with pyonephrosis and one with superficial wound infections). FDG PET/CT is helpful in evaluation of children and young adults with concern for spinal hardware infection. Noninfectious hardware complications and alternative sources of infection, including pneumonia and pyonephrosis, can be diagnosed. FDG PET/CT should be the first-line cross-sectional imaging study in

  13. Comparison of CT and MRI in the evaluation of therapeutic responce in thoracic Hodgkin disease

    International Nuclear Information System (INIS)

    Elkowitz, S.S.; Leonidas, J.C.; Lopez, M.; Cherick, I.; Schiff, R.G.; Karayalcin, G.; Lanzkowsky, P.

    1993-01-01

    Current imaging modalities are accurate in establishing the diagnosis and extent of thoracic Hodgkin disease. After treatment, however, it is extremely difficult to differentiate potential residual active neoplastic disease from scar tissue, or identify early recurrence. We evaluated the contribution of MRI in the assessment of the response to treatment of thoracic Hodgkin disease in the assumption that scar formation would be characterized by low signal intensity in all pulse sequences, whereas active tumor should maintain a degree of high signal intensity on T2-weighted images. In 47 occasions (23 patients) both CT and MRI were able to identify correctly active disease, but had low specificity in confirming remission because of residual tissues masses. High signal intensity on T2-weighted MR images often persisted despite remission, probably because of edema, necrosis, granulation or other factors. MRI was somewhat more specific than CT and may be quite valuable to confirm remission in patients with residual masses that no longer appear hyperintense on T 2 after treatment. (orig.)

  14. Evaluation of radiation dose in 64-row whole-body CT of multiple injured patients compared to 4-row CT; Evaluation der Strahlendosis bei Polytrauma-CT-Untersuchungen eines 64-Zeilen-CT im Vergleich zur 4-Zeilen-CT

    Energy Technology Data Exchange (ETDEWEB)

    Harrieder, A.; Geyer, L.L.; Koerner, M.; Deak, Z.; Wirth, S.; Reiser, M.; Linsenmaier, U. [Ludwig-Maximilians-Univ. Muenchen (Germany). Inst. fuer Klinische Radiologie

    2012-05-15

    Purpose: To evaluate radiation exposure in whole-body CT (WBCT) of multiple injured patients comparing 4-row multidetector computed tomography (MDCT) to 64-row MDCT. Materials and Methods: 200 WBCT studies were retrospectively evaluated: 92 4-row MDCT scans and 108 64-row MDCT scans. Each CT protocol was optimized for the particular CT system. The scan length, CT dose index (CTDI), and dose length product (DLP) were recorded and analyzed for radiation exposure. The mean effective dose was estimated based on conversion factors. Student's t-test was used for statistical analysis. Results: The mean CTDI{sub vol} values (mGy) of the thorax and abdomen were significantly reduced with 64-row MDCT (10.2 {+-} 2.5 vs. 11.4 {+-} 1.4, p < 0.001; 14.2 {+-} 3.7 vs. 16.1 {+-} 1.7, p < 0.001). The DLP values (mGy x cm) of the head and thorax were significantly increased with 64-row MDCT (1305.9 {+-} 201.1 vs. 849.8 {+-} 90.9, p < 0,001; 504.4 {+-} 134.4 vs. 471.5 {+-} 74.1, p = 0.030). The scan lengths (mm) were significantly increased with 64-row MDCT: head 223.6 {+-} 35.8 vs. 155.5 {+-} 12.3 (p < 0.001), thorax 427.4 {+-} 44.5 vs. 388.3 {+-} 57.5 (p < 0.001), abdomen 520.3 {+-} 50.2 vs. 490.8 {+-} 51.6 (p < 0.001). The estimated mean effective doses (mSv) were 22.4 {+-} 2.6 (4-row MDCT) and 24.1 {+-} 4.6 (64-row MDCT; p = 0.001), resulting in a percentage increase of 8 %. Conclusion: The radiation dose per slice of the thorax and abdomen can be significantly decreased by using 64-row MDCT. Due to the technical advances of modern 64-row MDCT systems, the scan field can be adapted to the clinical demands and, if necessary, enlarged without time loss. As a result, the estimated mean effective dose might be increased in WBCT. (orig.)

  15. Dimensional Changes of Fresh Sockets With Reactive Soft Tissue Preservation: A Cone Beam CT Study.

    Science.gov (United States)

    Crespi, Roberto; Capparé, Paolo; Crespi, Giovanni; Gastaldi, Giorgio; Gherlone, Enrico Felice

    2017-06-01

    The aim of this study was to assess dimensional changes of the fresh sockets grafted with collagen sheets and maintenance of reactive soft tissue, using cone beam computed tomography (CBCT). Tooth extractions were performed with maximum preservation of the alveolar housing, reactive soft tissue was left into the sockets and collagen sheets filled bone defects. Cone beam computed tomography were performed before and 3 months after extractions. One hundred forty-five teeth, 60 monoradiculars and 85 molars, were extracted. In total, 269 alveoli were evaluated. In Group A, not statistically significant differences were found between monoradiculars, whereas statistically significant differences (P 0.05) for all types of teeth. This study reported an atraumatic tooth extraction, reactive soft tissue left in situ, and grafted collagen sponge may be helpful to reduce fresh socket collapse after extraction procedures.

  16. Quantifying the usefulness of CT in evaluating seniors with abdominal pain

    International Nuclear Information System (INIS)

    Lewis, Lawrence M.; Klippel, Allen P.; Bavolek, Rebecca A.; Ross, Laura M.; Scherer, Tara M.; Banet, Gerald A.

    2007-01-01

    Objectives: (1) Determine if older patients with abdominal pain who receive emergency department (ED) abdominal CT have changes in diagnosis and/or disposition more often than similar patients without CT; (2) compare physician confidence in diagnosis and disposition for patients with versus without CT; (3) document factors that most influence physician's decision to order abdominal CT in this population. Methods: ED patients 60 years of age or older, with acute non-traumatic abdominal pain were enrolled over a 6-week period. Physicians documented a preliminary and final ED diagnosis and disposition, along with pre- and post-evaluation confidence levels. Decision to order CT, along with clinical information most influencing that decision, was noted. Physician confidence levels and percent change in diagnosis and disposition were compared for patients with versus without CT. Results: One hundred and twenty-six patients comprised study sample. Abdominal CT rate was 59% (95%CI, 50-67%). CT was associated with an increased change in diagnosis (46%; 95%CI, 4-58% versus 29%; 95%CI, 16-42%), but no change in disposition between patients with versus without CT. Preliminary diagnostic confidence was lower for EPs who ordered a CT than for those who did not (p < 0.001). Patient history most influenced ordering CT, whereas prior lab/imaging results most influenced not ordering CT. Conclusion: Patients with CT had a change in diagnosis more often than those without. Preliminary diagnostic confidence was lower in CT group. Percent change in disposition did not differ between groups. Physicians most often ordered CT based on history and did not order CT when other diagnostic evaluation supported a specific diagnosis

  17. Organ dose evaluation for CT scans based on in-phantom measurements

    International Nuclear Information System (INIS)

    Liu Haikuan; Zhuo Weihai; Chen Bo; Yi Yanling; Li Dehong

    2009-01-01

    Objective: To explore the organ doses and their distributions in different projections of CT scans. Methods: The CT values were measured and the linear absorption coefficients were derived for the main organs of the anthropomorphic phantom to compare with the normal values of human beings. The radiophotoluminescent glass dosimeters were set into various tissues or organs of the phantom for mimic measurements of the organ doses undergoing the head, chest, abdomen and pelvis CT scans, respectively. Results: The tissue equivalence of the phantom used in this study was good. The brain had the largest organ dose undergoing the head CT scan. The organ doses in thyroid, breast, lung and oesophagus were relatively large in performing the chest CT scan, while the liver, stomach, colon and lung had relatively hrge organ doses in abdomen CT practice. The doses in bone surface and colon exceeded by 50 mGy in a single pelvis CT scan. Conclusions: The organ doses and their distributions largely vary with different projections of CT scans. The organ doses of colon, bone marrow,gonads and bladder are fairly large in performing pelvis CT scan, which should be paid attention in the practice. (authors)

  18. Evaluation of a PACS workstation for interpreting body CT studies

    International Nuclear Information System (INIS)

    Franken, E.A.; Berbaum, K.S.; Honda, H.; McGuire, C.; Weis, R.R.; Barloon, T.

    1989-01-01

    This paper reports conventional hard-copy images from 266 body CT studies compared with those provided by a picture archiving and communication system (PACS) workstation. PACS images were evaluated before and after use of various image processing features. Most cases were depicted equally well, but in about one-fourth of the cases, diagnostic features were shown more clearly on PACS images. When PACS images were viewed first, a change in diagnosis after subsequent hardcopy inspection was infrequent, but when hard-copy images were viewed first, the results were converse. The image processing features of PACS were critical for its superior performance. The ability of a PACS to provide both image display and manipulation results in the superiority of that system

  19. Induced pneumoperitoneum in spiral CT evaluation of gastric cancer

    International Nuclear Information System (INIS)

    Guo Hua; Gao Jianbo; Li Yintai; Yang Xuehua; Chen Xuejun; Guan Sheng

    2001-01-01

    Objective: To evaluate the diagnostic value and clinical significance of preoperative staging in gastric cancer with induced pneumoperitoneum in spiral CT (SCTPP). Methods: Both routine SCT and SCTPP were performed in 52 lean patients suffered from gastric cancers, and comparison was made between SCT findings and surgical and histopathologic findings. Results: The accuracy of routine SCT and SCTPP in determining the T-staging was 72% and 96%, respectively (x 2 = 8.0, P 2 = 0.006, P > 0.05). The sensitivity in determining M-staging was 61% and 100%, respectively (x 2 = 0.04, P 2 6.03, P < 0.05). Conclusion: The accuracy of SCTPP in determining preoperative staging of gastric cancer was significantly higher than that of routine SCT. SCTPP has important guiding significance for the selection of the treatment strategy in gastric cancer

  20. Spiral CT for evaluation of chest trauma; Spiral-CT beim Thoraxtrauma

    Energy Technology Data Exchange (ETDEWEB)

    Roehnert, W. [Universitaetsklinikum Dresden (Germany). Inst. und Poliklinik fuer Radiologische Diagnostik; Weise, R. [Universitaetsklinikum Dresden (Germany). Inst. und Poliklinik fuer Radiologische Diagnostik

    1997-07-01

    After implementation of spiral CT in our department, we carried out an analysis for determining anew the value of CT as a modality of chest trauma diagnosis in the emergency department. The retrospective study covers a period of 10 months and all emergency patients with chest trauma exmined by spiral CT. The major lesions of varying seriousness covered by this study are: pneumothorax, hematothorax, pulmonary contusion or laceration, mediastinal hematoma, rupture of a vessel, injury of the heart and pericardium. The various fractures are not included in this study. In many cases, spiral CT within relatively short time yields significant diagnostic findings, frequently saving additional angiography. A rigid diagnostic procedure cannot be formulated. Plain-film chest radiography still remains a diagnostic modality of high value. (Orig.) [Deutsch] Nach Einfuehrung der Spiral-CT in unserer Einrichtung versuchten wir, den Stellenwert der Computertomographie in der Notfalldiagnostik des Thoraxtraumas neu zu bestimmen. Dazu wurden retrospektiv ueber einen Zeitraum von 10 Monaten alle mittels Spiral-CT untersuchten Notfallpatienten mit Thoraxverletzungen ausgewertet. Im Vordergrund standen folgende Befunde unterschiedlichen Schweregrades: Pneumothorax, Haematothorax, Lungenkontusion/-lazeration, Mediastinalhaematom, Gefaessruptur, Herz- und Herzbeutelverletzung. Auf die unterschiedlichen Frakturen wird bewusst nicht naeher eingegangen. In vielen Faellen liefert die Spiral-CT mit relativ geringem Zeitaufwand wesentliche diagnostische Aussagen. Haeufig kann auf eine Angiographie verzichtet werden. Ein starres diagnostisches Stufenschema laesst sich nicht definieren. Die Thoraxuebersichtsaufnahme besitzt einen unveraendert hohen Stellenwert. (orig.)

  1. Facet joint injuries in acute cervical spine trauma : evaluation with CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Jeon Ju; Kim, Dong Hyun; Lee, Jeong Hwa; Lee, Keon; Kwon, Hyeok Po; Kwon, Jung Hyeok; Yun, Seong Mun [Dongkang General Hospital, Seoul (Korea, Republic of)

    1999-05-01

    To evaluate injury patterns of facet joints and associated soft tissue injuries in patients with acute traumatic cervical facet joint injuries. From among patients with cervical spine trauma, 27 with facet joint injuries, as seen on CT and MRI, were chosen for this study. CT scans were analyzed with regard to the location of facet joint injury, the presence or absence of facet dislocation or fracture, and other associated fractures. MR images were analyzed with regard to ligament injury, intervertebral disc injury, intervertebral disc herniation, and spinal cord injury. The most common location of facet joint injury was C6-7 level(n=10), followed by C5-6(n=8). Among these 27 patients with facet joint injuries, 12(44%) had bilateral injuries and 15(56%) unilateral injuries. Facet fractures were present in 17 cases(63%) and the fracture of inferior facet was more frequent than superior. Patterns of fracture were vertical, transverse, or comminuted, but vertical fracture was the most common. Various degrees of dislocation were observed in patients with facet fractures. Fractures other than facet included pillar(n=11), lamina(n=6), transverse process(n=14), body(n=13), and spinous process(n=3). On MR images, anterior longitudinal ligament injury was found in 8 patients(30%), posterior longitudinal ligament injury in 4(15%), and interspinous ligament injury in 20(74%). Twelve patients(44%) had spinal cord injuries including edema(n=8) and hemorrhage(n=4). Among patients with disc abnormalities, 11(41%) had intervertebral disc injuries, and traumatic disc herniations were found in nine. Traumatic cervical facet joint injuries were manifested as various patterns and frequently associated with other fractures or soft tissue injuries. Analysis of CT and MR findings of these injury patterns helped formulate a therapeutic plan and determine of prognosis.

  2. The role of 18F-FDG PET and PET/CT in the evaluation of primary cutaneous lymphoma.

    Science.gov (United States)

    Qiu, Lin; Tu, Guojian; Li, Jing; Chen, Yue

    2017-02-01

    Primary cutaneous lymphoma (PCL) is the second most common type of extranodal non-Hodgkin lymphoma, including both cutaneous T-cell and B-cell lymphomas. PCL comprises numerous subtypes and thus has myriad clinical presentations in the skin and subcutaneous tissues. Accurate classification and staging are important for making treatment recommendations for PCL and will further impact patient prognosis significantly. We review the role of fluorine-18-fluorodeoxyglucose (F-FDG) PET (F-FDG PET) and F-FDG PET with computed tomography (CT) in the diagnosis, staging, tumor biological evaluation, treatment response assessment, and early recurrence surveillance of PCL. Although F-FDG PET and PET/CT do not seem to adequately distinguish the plaque, patch, or erythroderma cutaneous lesions of PCL, the imaging modalities are superior to CT, MRI, and other nuclear medicine methods in detecting both the cutaneous and the extracutaneous lesions of PCL. The available literature addressing the clinical role of F-FDG PET and PET/CT in patients with PCL is promising for the use of the modalities in staging, tumor biological evaluation, biopsy guidance, early treatment response assessment, and recurrence surveillance. However, more data are needed to better specify the role of F-FDG PET and PET/CT in the management of PCL.

  3. Hypoxic-ischemic encephalopathy in neonates and infants: an evaluation with spiral CT

    International Nuclear Information System (INIS)

    Zhu Linghua

    2006-01-01

    Objective: To evaluate spiral CT imaging in the diagnosis of hypoxic-ischemic encephalopathy (HIE) in the neonates and infants. Methods: 112 children with history of asphyxia in peri-natal period and evident clinical symptoms were evaluated with Spiral CT. CT findings were studied. Results: 46 minor cases, 57 moderate cases and 9 severe cases were found out of 112 patients. Intracranial hemorrhage was revealed in 38 cases. Mortality occurred in 1 case. Conclusion: Spiral CT is helpful for evaluating brain damage and predicting prognosis in neonates with HIE. (authors)

  4. Comprehensive evaluation of ten deformable image registration algorithms for contour propagation between CT and cone-beam CT images in adaptive head & neck radiotherapy.

    Science.gov (United States)

    Li, Xin; Zhang, Yuyu; Shi, Yinghua; Wu, Shuyu; Xiao, Yang; Gu, Xuejun; Zhen, Xin; Zhou, Linghong

    2017-01-01

    Deformable image registration (DIR) is a critical technic in adaptive radiotherapy (ART) for propagating contours between planning computerized tomography (CT) images and treatment CT/cone-beam CT (CBCT) images to account for organ deformation for treatment re-planning. To validate the ability and accuracy of DIR algorithms in organ at risk (OAR) contour mapping, ten intensity-based DIR strategies, which were classified into four categories-optical flow-based, demons-based, level-set-based and spline-based-were tested on planning CT and fractional CBCT images acquired from twenty-one head & neck (H&N) cancer patients who underwent 6~7-week intensity-modulated radiation therapy (IMRT). Three similarity metrics, i.e., the Dice similarity coefficient (DSC), the percentage error (PE) and the Hausdorff distance (HD), were employed to measure the agreement between the propagated contours and the physician-delineated ground truths of four OARs, including the vertebra (VTB), the vertebral foramen (VF), the parotid gland (PG) and the submandibular gland (SMG). It was found that the evaluated DIRs in this work did not necessarily outperform rigid registration. DIR performed better for bony structures than soft-tissue organs, and the DIR performance tended to vary for different ROIs with different degrees of deformation as the treatment proceeded. Generally, the optical flow-based DIR performed best, while the demons-based DIR usually ranked last except for a modified demons-based DISC used for CT-CBCT DIR. These experimental results suggest that the choice of a specific DIR algorithm depends on the image modality, anatomic site, magnitude of deformation and application. Therefore, careful examinations and modifications are required before accepting the auto-propagated contours, especially for automatic re-planning ART systems.

  5. Comprehensive evaluation of ten deformable image registration algorithms for contour propagation between CT and cone-beam CT images in adaptive head & neck radiotherapy.

    Directory of Open Access Journals (Sweden)

    Xin Li

    Full Text Available Deformable image registration (DIR is a critical technic in adaptive radiotherapy (ART for propagating contours between planning computerized tomography (CT images and treatment CT/cone-beam CT (CBCT images to account for organ deformation for treatment re-planning. To validate the ability and accuracy of DIR algorithms in organ at risk (OAR contour mapping, ten intensity-based DIR strategies, which were classified into four categories-optical flow-based, demons-based, level-set-based and spline-based-were tested on planning CT and fractional CBCT images acquired from twenty-one head & neck (H&N cancer patients who underwent 6~7-week intensity-modulated radiation therapy (IMRT. Three similarity metrics, i.e., the Dice similarity coefficient (DSC, the percentage error (PE and the Hausdorff distance (HD, were employed to measure the agreement between the propagated contours and the physician-delineated ground truths of four OARs, including the vertebra (VTB, the vertebral foramen (VF, the parotid gland (PG and the submandibular gland (SMG. It was found that the evaluated DIRs in this work did not necessarily outperform rigid registration. DIR performed better for bony structures than soft-tissue organs, and the DIR performance tended to vary for different ROIs with different degrees of deformation as the treatment proceeded. Generally, the optical flow-based DIR performed best, while the demons-based DIR usually ranked last except for a modified demons-based DISC used for CT-CBCT DIR. These experimental results suggest that the choice of a specific DIR algorithm depends on the image modality, anatomic site, magnitude of deformation and application. Therefore, careful examinations and modifications are required before accepting the auto-propagated contours, especially for automatic re-planning ART systems.

  6. CT and MR imaging features in phosphaturic mesenchymal tumor-mixed connective tissue: A case report.

    Science.gov (United States)

    Shi, Zhenshan; Deng, Yiqiong; Li, Xiumei; Li, Yueming; Cao, Dairong; Coossa, Vikash Sahadeo

    2018-04-01

    Phosphaturic mesenchymal tumor-mixed connective tissue (PMT-MCT) is rare and usually benign and slow-growing. The majority of these tumors is associated with sporadic tumor-induced osteomalacia (TIO) or rickets, affect middle-aged individuals and are located in the extremities. Previous imaging studies often focused on seeking the causative tumors of TIO, not on the radiological features of these tumors, especially magnetic resonance imaging (MRI) features. PMT-MCT remains a largely misdiagnosed, ignored or unknown entity by most radiologists and clinicians. In the present case report, a review of the known literature of PMT-MCT was conducted and the CT and MRI findings from three patient cases were described for diagnosing the small subcutaneous tumor. Typical MRI appearances of PMT-MCT were isointense relative to the muscles on T1-weighted imaging, and markedly hyperintense on T2-weighted imaging containing variably flow voids, with markedly heterogeneous/homogenous enhancement on post contrast T1-weighted fat-suppression imaging. Short time inversion recovery was demonstrated to be the optimal sequence in localizing the tumor.

  7. Interobserver variability in visual evaluation of thoracic CT scans and comparison with automatic computer measurements of CT lung density

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Thomsen, Laura Hohwü; Dirksen, Asger

    2012-01-01

    lung density measurements, i.e. densitometry. Methods – In a pilot study 60 CT scans were selected from a sample of 3980 CT scans from The Danish Lung Cancer Screening Trial (DLCST). The amount of emphysema in these scans was scored independently by two observers, who were blinded regarding clinical...... information. The lung was segmented automatically by in-house developed computer software, and the percentage of pixels below -950 HU was used as a surrogate marker for emphysema. The observer variability, as well as the correlation with the lung density measurements, was analysed using Spearman’s rank...... in emphysema grading. However, the agreement with the CT lung density measurement was poor, indicating that the two types of evaluation represent different aspects of emphysema. Most likely, they should be seen as complementary rather than competitive evaluations. Future comparison with physiological tests...

  8. Multi-slice CT pulmonary function evaluation in emphysema

    International Nuclear Information System (INIS)

    Ge Xiaojun; Zhang Guozhen; Zhu Yanping; Shan Lin; Mao Dingbiao; Ding Qiyong; Hua Yanqing

    2007-01-01

    Objective: To explore the feasibility of evaluating the lung function by MSCT in emphysema. Methods: The MSCT scan and pulmonary function tests (PFT) were respectively performed in 147 receptors within one week. They were randomly divided into 2 groups: group A (120 receptors), including normal, mild, moderate and severe abnormal pulmonary function based on the PFT, for comparing the correlation between pulmonary quantitative indexes of MSCT pulmonary function and PFT and settingup the primary, grade criteria of abnormal pulmonary, function in emphysema, group B (27 receptors) for evaluating the diagnostic accuracy in group A. The total lung was respectively scanned at the full inspiration and full expiration with MSCT. The pulmonary quantitative indexes of MSCT were measured with Siemens Pulmo pulmonary quantitative software. Results: There was correlation between pulmonary quantitative indexes of MSCT and PFT. The Piex/in -910 showed best correlation with FEV 1 % (r= -0. 905, P -910 (χ 2 0.267, P=0.966, accuracy 81.5%), and the primary criteria for abnormal pulmonary, function of emphysema was normal (0-9.9), mild (10.0-34.9), moderate (35.0-74.9) and severe (≥75.0). Conclusion: It is feasible to evaluate the abnormal lung function of emphysema with pulmonary quantitative indexes of CT. The Piex/in 910 was the most effective one in various indexes. (authors)

  9. The anterior cruciate ligament: a study on its bony and soft tissue anatomy using novel 3D CT technology.

    Science.gov (United States)

    Tampere, Thomas; Van Hoof, Tom; Cromheecke, Michiel; Van der Bracht, Hans; Chahla, Jorge; Verdonk, Peter; Victor, Jan

    2017-01-01

    The purpose of this study is twofold: first, to visualize both the tibial and femoral bony insertion surfaces and second, to describe the anterior cruciate ligament (ACL) geometrically, using novel 3D CT imaging. In addition, new concepts of best-fit cylinder and central axis are introduced and evaluated. Eight unpaired knees of embalmed cadavers were used in this study. Following the dissection process, the ACL was injected with a contrast medium for CT imaging. The obtained CT images in extension, 45°, 90° and full flexion were segmented and rendered in 3D allowing morphological and morphometric analysis of the ACL. Anatomical footprint centres, femoral and tibial footprint surface area, best-fit ACL-cylinder intersection area, best-fit ACL-cylinder/footprint coverage ratio, best-fit ACL-cylinder central axis projections at the tibial and femoral footprint in the four positions were used to describe the anatomy of the ACL, based on the Bernard, Hertel and Amis grid. Based on these parameters, with the best-fit cylinder representing the bulk of the ACL, a changing fibre-recruitment pattern was seen with a moving position of the central axis from posterior to anterior on the femoral and tibial footprint, going from extension to flexion. Furthermore, the numerical data show an increase in tibial footprint coverage by the best-fit cylinder through the ACL when the knee is progressively flexed, whereas an inverse relationship was seen on the femoral side. This study is the first to describe the detailed anatomy of the human ACL with respect to its course and footprints using a 3D approach. It confirms the large difference and inter-patient variability between the tibial and femoral footprint area with the former being significantly smaller. The best-fit cylinder concept illustrates the recruitment pattern of the native ACL where in extension the postero-lateral fibres are recruited and in flexion rather the antero-medial bundle, which can be valuable information in

  10. A pilot study of FDG PET/CT detects a link between brown adipose tissue and breast cancer

    International Nuclear Information System (INIS)

    Cao, Qi; Jones, Laundette; Hersl, Jerome; La, Hongloan; Smith, Mark; Jenkins, Jason; Goloubeva, Olga; Dilsizian, Vasken; Tkaczuk, Katherine; Chen, Wengen

    2014-01-01

    Breast cancer is the second most lethal cancer in women. Understanding biological mechanisms that cause progression of this disease could yield new targets for prevention and treatment. Recent experimental studies suggest that brown adipose tissue (BAT) may play a key role in breast cancer progression. The primary objective for this pilot study was to determine if the prevalence of active BAT in patients with breast cancer is increased compared to cancer patients with other malignancies. We retrospectively analyzed data from 96 breast cancer patients who had FDG PET/CT scan for routine staging at the University of Maryland and 96 age- and weight-matched control female patients with other malignancies (predominantly colon cancer) who had undergone FDG PET/CT imaging on the same day. Data on the distribution (bilateral upper neck, supraclavicular and paraspinal regions) and intensity (SUVmax) of active BAT were evaluated by 2 Nuclear Medicine physicians, blinded to the clinical history. We found sufficient evidence to conclude that based on our sample data the prevalence of active BAT in breast cancer patients’ group is significantly different from that in the control group. The estimated frequency of BAT activity was 3 fold higher in breast cancer patients as compared to controls with other cancers, (16.7% vs. 5.2%, respectively, p = 0.019). When patients were stratified by age in order to determine the possible impact of age related hormonal changes on active BAT among the younger women (≤ 55 years of age), 25.6% breast cancer patients exhibited BAT activity compared to only 2.8% in control women (p = 0.007). In contrast, among the older women (> 55 years of age), the prevalence of active BAT was similar among breast cancer and control women (10.7% vs 6.7%). In breast cancer patients prevalence of BAT activity on FDGPET/CT is 3-fold greater than in age- and body weight-matched patients with other solid tumor malignancies; this difference is particularly

  11. Estimation of diastolic filling pressure with cardiac CT in comparison with echocardiography using tissue doppler imaging: Determination of optimal CT reconstruction parameters

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji Sun; Suh, Jon; Lee, Heon [Soonchunhyang University Hospital Bucheon, Bucheon (Korea, Republic of); Lee, Bora [Dept. of Biostatistics, Soonchunhyang University College of Medicine, Seoul (Korea, Republic of); Lee, Soo Jeong [Terarecon Korea, Seoul (Korea, Republic of); Jou, Sung Shick [Dept. of Radiology, Soonchunhyang University Hospital Cheonan, Cheonan (Korea, Republic of); Lim, Hyun Kyung [Dept. of Radiology, Soonchunhyang University Hospital Seoul, Seoul (Korea, Republic of)

    2017-08-01

    To determine the optimal CT image reconstruction parameters for the measurement of early transmitral peak velocity (E), early peak mitral septal tissue velocity (E′), and E / E′. Forty-six patients underwent simultaneous cardiac CT and echocardiography on the same day. Four CT datasets were reconstructed with a slice thickness/interval of 0.9/0.9 mm or 3/3 mm at 10 (10% RR-interval) or 20 (5% RR-interval) RR-intervals. The E was calculated by dividing the peak transmitral flow (mL/s) by the corresponding mitral valve area (cm{sup 2}). E′ was calculated from the changes in the left ventricular length per cardiac phase. E / E′ was then estimated and compared with that from echocardiography. For assessment of E / E′, CT and echocardiography were more strongly correlated (p < 0.05) with a slice thickness of 0.9 mm and 5% RR-interval (r = 0.77) than with 3 mm or 10% RR-interval. The diagnostic accuracy of predicting elevated filling pressure (E / E′ ≥ 13, n = 14) was better with a slice thickness of 0.9 mm and 5% RR-interval (87.0%) than with 0.9 mm and 10% RR-interval (71.7%) (p = 0.123) and significantly higher than that with a slice thickness of 3 mm with 5% (67.4%) and 10% RR-interval (63.0%), (p < 0.05), respectively. Data reconstruction with a slice thickness of 0.9 mm at 5% RR-interval is superior to that with a slice thickness of 3 mm or 10% RR-interval in terms of the correlation of E / E′ between CT and echocardiography. Thin slices and frequent sampling also allow for more accurate prediction of elevated filling pressure.

  12. Clinical evaluation of high-resolution CT, 1. CT diagnosis of liver tumors and its limit

    Energy Technology Data Exchange (ETDEWEB)

    Araki, T [Tokyo Univ. (Japan). Faculty of Medicine

    1980-03-01

    To estimate diagnostic accuracy of CT in liver tumors, CT diagnosis in 120 patients with primary hepatocellular carcinoma was discussed. As a result, primary hepatocellular carcinoma less than 2 cm in diameter could not be visualized by CT. Even tumors between 4 and 8 cm in diameter showed false negative caused by isodense tumors on images of 4 patients. To improve the detectability of liver tumors by CT, the higher resolution of low contrast regions on images are required. As a method to improve qualitative diagnosis of liver tumors, rapid intravenous injection of contrast medium was performed on 42 patients with liver tumors, As a result, images reflecting vascularity of tumors were obtained, and the differential diagnosis was possible to some extent by observing the movement of the contrast. Especially, cavernous hemangioma could be distinguished from hepatocellular carcinoma, because cavernous hemangioma showed specific images and could be diagnosed accurately.

  13. Evaluation of pre and post-operative spinal plain CT and CT-myelography

    International Nuclear Information System (INIS)

    Nagase, Joji; Inoue, Shunichi; Miyasaka, Hitoshi; Kamata, Sakae; Shinohara, Hiroyasu.

    1983-01-01

    Confirmation of the level of scan slices is essential for the CT diagnosis of spinal and spinal-cord diseases. Pre- and postoperative comparison should be made on the same level. For reading of plain CT and CTM, window levels should be identical pre- and postoperatively. Both methods demonstrated the spinal canal, morphology of the spinal cord, and three-Fdimensional pathologic pictures inside and outside the spinal cord. Preoperative CT contributed useful information on the pathologic conditions and selection of surgical procedures and routes. Postoperative plain CT confirmed surgical results, and CTM revealed the spinal cord and the subarachnoid space, as well as the range and degree of decompression from the spinal cord. (Chiba, N.)

  14. Bone quality evaluation at dental implant site using multislice CT, micro-CT, and cone beam CT

    NARCIS (Netherlands)

    Parsa, A.; Ibrahim, N.; Hassan, B.; van der Stelt, P.; Wismeijer, D.

    2015-01-01

    Objectives The first purpose of this study was to analyze the correlation between bone volume fraction (BV/TV) and calibrated radiographic bone density Hounsfield units (HU) in human jaws, derived from micro-CT and multislice computed tomography (MSCT), respectively. The second aim was to assess the

  15. SU-C-17A-03: Evaluation of Deformable Image Registration Methods Between MRI and CT for Prostate Cancer Radiotherapy

    International Nuclear Information System (INIS)

    Wen, N; Glide-Hurst, C; Zhong, H; Chin, K; Kumarasiri, A; Liu, C; Liu, M; Siddiqui, S

    2014-01-01

    Purpose: We evaluated the performance of two commercially available and one open source B-Spline deformable image registration (DIR) algorithms between T2-weighted MRI and treatment planning CT using the DICE indices. Methods: CT simulation (CT-SIM) and MR simulation (MR-SIM) for four prostate cancer patients were conducted on the same day using the same setup and immobilization devices. CT images (120 kVp, 500 mAs, voxel size = 1.1x1.1x3.0 mm3) were acquired using an open-bore CT scanner. T2-weighted Turbo Spine Echo (T2W-TSE) images (TE/TR/α = 80/4560 ms/90°, voxel size = 0.7×0.7×2.5 mm3) were scanned on a 1.0T high field open MR-SIM. Prostates, seminal vesicles, rectum and bladders were delineated on both T2W-TSE and CT images by the attending physician. T2W-TSE images were registered to CT images using three DIR algorithms, SmartAdapt (Varian), Velocity AI (Velocity) and Elastix (Klein et al 2010) and contours were propagated. DIR results were evaluated quantitatively or qualitatively by image comparison and calculating organ DICE indices. Results: Significant differences in the contours of prostate and seminal vesicles were observed between MR and CT. On average, volume changes of the propagated contours were 5%, 2%, 160% and 8% for the prostate, seminal vesicles, bladder and rectum respectively. Corresponding mean DICE indices were 0.7, 0.5, 0.8, and 0.7. The intraclass correlation coefficient (ICC) was 0.9 among three algorithms for the Dice indices. Conclusion: Three DIR algorithms for CT/MR registration yielded similar results for organ propagation. Due to the different soft tissue contrasts between MRI and CT, organ delineation of prostate and SVs varied significantly, thus efforts to develop other DIR evaluation metrics are warranted. Conflict of interest: Submitting institution has research agreements with Varian Medical System and Philips Healthcare

  16. SU-C-17A-03: Evaluation of Deformable Image Registration Methods Between MRI and CT for Prostate Cancer Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Wen, N; Glide-Hurst, C; Zhong, H; Chin, K; Kumarasiri, A; Liu, C; Liu, M; Siddiqui, S [I Chetty, Henry Ford Health System, Detroit, MI (United States)

    2014-06-15

    Purpose: We evaluated the performance of two commercially available and one open source B-Spline deformable image registration (DIR) algorithms between T2-weighted MRI and treatment planning CT using the DICE indices. Methods: CT simulation (CT-SIM) and MR simulation (MR-SIM) for four prostate cancer patients were conducted on the same day using the same setup and immobilization devices. CT images (120 kVp, 500 mAs, voxel size = 1.1x1.1x3.0 mm3) were acquired using an open-bore CT scanner. T2-weighted Turbo Spine Echo (T2W-TSE) images (TE/TR/α = 80/4560 ms/90°, voxel size = 0.7×0.7×2.5 mm3) were scanned on a 1.0T high field open MR-SIM. Prostates, seminal vesicles, rectum and bladders were delineated on both T2W-TSE and CT images by the attending physician. T2W-TSE images were registered to CT images using three DIR algorithms, SmartAdapt (Varian), Velocity AI (Velocity) and Elastix (Klein et al 2010) and contours were propagated. DIR results were evaluated quantitatively or qualitatively by image comparison and calculating organ DICE indices. Results: Significant differences in the contours of prostate and seminal vesicles were observed between MR and CT. On average, volume changes of the propagated contours were 5%, 2%, 160% and 8% for the prostate, seminal vesicles, bladder and rectum respectively. Corresponding mean DICE indices were 0.7, 0.5, 0.8, and 0.7. The intraclass correlation coefficient (ICC) was 0.9 among three algorithms for the Dice indices. Conclusion: Three DIR algorithms for CT/MR registration yielded similar results for organ propagation. Due to the different soft tissue contrasts between MRI and CT, organ delineation of prostate and SVs varied significantly, thus efforts to develop other DIR evaluation metrics are warranted. Conflict of interest: Submitting institution has research agreements with Varian Medical System and Philips Healthcare.

  17. Evaluation of radiation doses delivered in different chest CT protocols

    International Nuclear Information System (INIS)

    Gorycki, Tomasz; Lasek, Iwona; Kamiński, Kamil; Studniarek, Michał

    2014-01-01

    There are differences in the reference diagnostic levels for the computed tomography (CT) of the chest as cited in different literature sources. The doses are expressed either in weighted CT dose index (CTDI VOL ) used to express the dose per slice, dose-length product (DLP), and effective dose (E). The purpose of this study was to assess the radiation dose used in Low Dose Computer Tomography (LDCT) of the chest in comparison with routine chest CT examinations as well as to compare doses delivered in low dose chest CT with chest X-ray doses. CTDI VOL and DLP doses were taken to analysis from routine CT chest examinations (64 MDCT TK LIGHT SPEED GE Medical System) performed in 202 adult patients with FBP reconstruction: 51 low dose, 106 helical, 20 angio CT, and 25 high resolution CT protocols, as well as 19 helical protocols with iterative ASIR reconstruction. The analysis of chest X-ray doses was made on the basis of reports from 44 examinations. Mean values of CTDI VOL and DLP were, respectively: 2.1 mGy and 85.1 mGy·cm, for low dose, 9.7 mGy and 392.3 mGy·cm for helical, 18.2 mGy and 813.9 mGy·cm for angio CT, 2.3 mGy and 64.4 mGy·cm for high resolution CT, 8.9 mGy. and 317.6 mGy·cm for helical ASIR protocols. Significantly lower CTDI VOL and DLP values were observed for low dose and high resolution CT versus the remaining CT protocols; doses delivered in CT ASIR protocols were also lower (80–81%). The ratio between medial doses in low dose CT and chest X-ray was 11.56. Radiation dose in extended chest LDCT with parameters allowing for identification of mediastinal structures and adrenal glands is still much lower than that in standard CT protocols. Effective doses predicted for LDCT may exceed those used in chest X-ray examinations by a factor of 4 to 12, depending on LDCT scan parameters. Our results, as well as results from other authors, suggest a possibility of reducing the dose by means of iterative reconstruction. Efforts towards further dose

  18. Evaluation of diagnostic quality in musculoskeletal three-dimensional CT scans

    International Nuclear Information System (INIS)

    Vannier, M.W.; Hildebolt, C.F.; Gilula, L.A.; Sutherland, C.J.; Offutt, C.J.; Drebin, R.; Mantle, M.; Giordono, T.A.

    1988-01-01

    A major application of three-dimensional computed tomography (CT) is in the imaging of the skeleton. Three-dimensional CT has an important role in determining the presence and extent of congenital and acquired orthopedic abnormalities. The objective of this study was to compare the diagnostic sensitivity and specificity of three-dimensional CT, planar CT, and plain radiography in the detection and characterization of orthopedic abnormalities. Three-dimensional CT scan reconstructions were obtained by two methods, surface reconstruction and volumetric techniques. Seventy patients were imaged with CT, three-dimensional CT, and plain radiography. The consensus opinion of experts with access to all images plus clinical history, surgical findings, and follow-up findings were taken as truth. Expert radiologists read these cases in a blinded fashion. The results were compared using receiver operating characteristic (ROC) analysis. The diagnostic value of each three-dimensional reconstruction method and the parameters used to perform the reconstructions were evaluated

  19. Comparative evaluation of the porta hepatis/hepatoduodenal ligament with CT and MR imaging

    International Nuclear Information System (INIS)

    Silverman, P.M.; Feuerstein, I.M.; Zeman, R.K.; Jaffe, M.H.; Garra, B.S.

    1988-01-01

    CT and MR imaging were compared in a retrospective evaluation of 16 patients with abnormalities, predominantly neoplasms, of the porta hepatis/hepatoduodenal ligament. Masses on CT were of decreased density compared with that of liver and were seen in contrast to surrounding periportal fat. On MR images, T1-weighted images demonstrated findings similar to those of CT. T2-weighted images clearly depicted intrahepatic lesions but less distinctly depicted lesions surrounded by fat. Short inversion recovery (STIR) images better demonstrated tumor relative to fat. CT was better than all MR imaging sequences in one of 16 cases, whereas at least one MR imaging sequence was better than CT in six of 16. In nine cases, CT was equivalent to the best MR imaging sequence. In five of six cases where MR imaging was better than CT, STIR sequences were most favorable. In conclusion, MR imaging provided a valuable technique for assessing abnormalities of the porta hepatis/hepatoduodenal ligament

  20. The clinical evaluation of CT and radionuclide examination in renal diseases

    International Nuclear Information System (INIS)

    Kutani, Wataru; Ishida, Hirofumi; Shirakawa, Shigetoshi; Shintaku, Takao; Funaki, Ryo

    1980-01-01

    One hundred and twelve cases of renal diseases were studied by computed tomography (CT) using EMI 5005/12. Of them, 60 were examined by both CT and renal scintigraphy, and comparatively evaluated. The CT units were checked before and after the contrast enhancement. Renal scintigrams were obtained by gamma cameras (PHO/GAMMA HP 6406, PHO/GAMMA LFOV) using 99 M Tc-DMSA. CT was especially useful in diagnosing the renal cysts and the hydronephrosis. Cysts in other organs (liver, spleen and pancreas) were simultaneously ascertained in polycystic diseases. CT was not helpful in diagnosing nephritis and diabetic nephropathy. Floating kidney and horse-shoe kidney were difficult to diagnose with CT. The renal scintigram was the reflection of the renal function, and was relatively more useful than CT in diagnosing horse-shoe kidney, floating kidney and nephritis, while it was not useful for non-functioning kidneys. (author)

  1. CT evaluation of mass lesions in the parotid region

    International Nuclear Information System (INIS)

    Matsumoto, Shunichi; Kishikawa, Takashi; Kudo, Sho; Miyaji, Hiroshi; Kuwano, Haruo; Kaneko, Kuniyuki; Ohuchida, Toshiyuki

    1988-01-01

    CT findings of 35 patients with proven 31 parotid gland mass lesions (23 benign tumors, 5 malignant tumors, 3 inflammatory diseases) and 4 infraauricular lymphadenopathy (2 inflammatory nodes, 2 neoplastic nodes) were reviewed. CT accurately diagnosed the parotid origin in 29 of 31 parotid gland diseases. In all four patients with infraauricular lymphadenopathy, differentiation from parotid tumor was difficult. CT differentiation between superficial and deep lobe tumors agreed with surgical findings in 18 of 21 parotid gland tumors. Twenty out of 23 benign parotid gland tumors appeared as discrete masses with smooth margins. All five malignant parotid gland tumors appeared as poorly defined masses. It is concluded that when a tumor is located in the superficial lobe and appears as a sharply circumscribed mass on plain CT, it should be diagnosed as a benign lesion and contrast CT is not required. Secondly, contrast CT would be beneficial when a tumor is indistinct, or located in the deep portion of the parotid gland on plain CT. Finally, CT-sialography is considered unnecessary in the diagnosis of parotid masses. (author)

  2. Evaluation of CT images on metastasis to cervical lymph node in patients with oral cancer

    International Nuclear Information System (INIS)

    Fujiki, Tomokazu; Wada, Takurou; Wakasa, Toru; Yanagi, Yoshinobu; Honda, Yasutoshi; Kawai, Noriko; Kishi, Kanji

    1998-01-01

    There have been many reports about the usefulness of CT in diagnosing cervical lymph node metastasis from oral cancer. With relatively high diagnostic accuracy, various diagnostic criteria have been used. This study evaluated CT images of cervical lymph node metastasis in patients with oral cancer using these criteria. Eighty-nine cases of various oral cancers (132 lymph node groups) were evaluated regarding cervical lymph node metastasis. In patients with nodes measuring over 1 cm in minimal axial diameter, 58.1% were metastatic (metastatic/total=47/74), while 17.2% of patients with nodes measuring less than 1 cm in minimal axial diameter of lymph node were metastatic (10/58). As for other diagnostic criteria, in patients with spherical nodes, 38.7% (metastatic/total=29/75), in patients showing ring enhancement, 70.4% (19/27) and in patients with fusion, 75.0% (3/4) were metastatic. In addition, in patients with spherical nodes measuring over 1 cm in minimal axial diameter, 59.5% (22/37), in patients with nodes measuring over 1 cm in minimal axial diameter and showing ring enhancement, 78.3% (18/23), in patients with spherical nodes showing ring enhancement, 60.0% (9/15) and in patients with spherical nodes measuring over 1 cm in minimal axial diameter and showing ring enhancement, 64.3% (9/14) were metastatic. In case of disappearance of fat layer (1/1), cancer infiltration of the surrounding tissue was seen. In conclusion, over 1 cm in minimal axial diameter, spherical node and ring enhancement were found to be appropriate diagnostic criteria. Furthermore, CT is essential in diagnosing cervical lymph node metastasis from oral cancer. (author)

  3. An Inset CT Specimen for Evaluating Fracture in Small Samples of Material

    Science.gov (United States)

    Yahyazadehfar, M.; Nazari, A.; Kruzic, J.J.; Quinn, G.D.; Arola, D.

    2013-01-01

    In evaluations on the fracture behavior of hard tissues and many biomaterials, the volume of material available to study is not always sufficient to apply a standard method of practice. In the present study an inset Compact Tension (inset CT) specimen is described, which uses a small cube of material (approximately 2×2×2 mm3) that is molded within a secondary material to form the compact tension geometry. A generalized equation describing the Mode I stress intensity was developed for the specimen using the solutions from a finite element model that was defined over permissible crack lengths, variations in specimen geometry, and a range in elastic properties of the inset and mold materials. A validation of the generalized equation was performed using estimates for the fracture toughness of a commercial dental composite via the “inset CT” specimen and the standard geometry defined by ASTM E399. Results showed that the average fracture toughness obtained from the new specimen (1.23 ± 0.02 MPa•m0.5) was within 2% of that from the standard. Applications of the inset CT specimen are presented for experimental evaluations on the crack growth resistance of dental enamel and root dentin, including their fracture resistance curves. Potential errors in adopting this specimen are then discussed, including the effects of debonding between the inset and molding material on the estimated stress intensity distribution. Results of the investigation show that the inset CT specimen offers a viable approach for studying the fracture behavior of small volumes of structural materials. PMID:24268892

  4. Evaluation of the tumor registration error in biopsy procedures performed under real-time PET/CT guidance.

    Science.gov (United States)

    Fanchon, Louise M; Apte, Adytia; Schmidtlein, C Ross; Yorke, Ellen; Hu, Yu-Chi; Dogan, Snjezana; Hatt, Mathieu; Visvikis, Dimitris; Humm, John L; Solomon, Stephen B; Kirov, Assen S

    2017-10-01

    The purpose of this study is to quantify tumor displacement during real-time PET/CT guided biopsy and to investigate correlations between tumor displacement and false-negative results. 19 patients who underwent real-time 18 F-FDG PET-guided biopsy and were found positive for malignancy were included in this study under IRB approval. PET/CT images were acquired for all patients within minutes prior to biopsy to visualize the FDG-avid region and plan the needle insertion. The biopsy needle was inserted and a post-insertion CT scan was acquired. The two CT scans acquired before and after needle insertion were registered using a deformable image registration (DIR) algorithm. The DIR deformation vector field (DVF) was used to calculate the mean displacement between the pre-insertion and post-insertion CT scans for a region around the tip of the biopsy needle. For 12 patients one biopsy core from each was tracked during histopathological testing to investigate correlations of the mean displacement between the two CT scans and false-negative or true-positive biopsy results. For 11 patients, two PET scans were acquired; one at the beginning of the procedure, pre-needle insertion, and an additional one with the needle in place. The pre-insertion PET scan was corrected for intraprocedural motion by applying the DVF. The corrected PET was compared with the post-needle insertion PET to validate the correction method. The mean displacement of tissue around the needle between the pre-biopsy CT and the postneedle insertion CT was 5.1 mm (min = 1.1 mm, max = 10.9 mm and SD = 3.0 mm). For mean displacements larger than 7.2 mm, the biopsy cores gave false-negative results. Correcting pre-biopsy PET using the DVF improved the PET/CT registration in 8 of 11 cases. The DVF obtained from DIR of the CT scans can be used for evaluation and correction of the error in needle placement with respect to the FDG-avid area. Misregistration between the pre-biopsy PET and the CT acquired with the

  5. Evaluation of cine CT in the investigation of patients with recurrent symptoms following coronary bypass grafting

    International Nuclear Information System (INIS)

    Rees, M.R.; MacMillan, R.M.; Eldredge, W.J.; Maranhao, V.

    1986-01-01

    Between May 1985 and July 1986, cine-CT was performed in 84 consecutive patients to evaluate graft patency and ventricular function. Only three studies (4%) were unsatisfactory. Compared to catheterization, an accuracy of 94% was found for graft patency, with a significant correlation for ejection fraction (r = .93). Close agreement with angiography was demonstrated for cine-CT detection of left ventricular wall motion abnormalities and graft flow. Compared to surgical placement, cine-CT localization of grafts in major coronary territories was 98% accurate. Despite a significant learning curve in study interpretation, cine-CT can be used in place of catheterization in the evaluation of symptomatic postgraft patients

  6. Preoperative CT evaluation of adenocarcinoma of the gastroesophageal junction

    International Nuclear Information System (INIS)

    Bennett, J.D.; Lefcoe, M.S.; Finley, R.; Yoshi, C.; Inculet, R.

    1988-01-01

    A retrospective review was undertaken of 53 preoperative computed tomographic (CT) scans obtained between March 1983 and April 1988 from patients undergoing surgery for adenocarcinoma of the gastroesophageal junction, and results were correlated with the surgical-pathologic findings. CT was unreliable in predicting aortic, pericardial, or pancreatic invasion (sensitivity, 0/8; specificity, 41/45). Of 45 pathologically positive nodal groups, the largest node measured on CT scans was 10 mm or less in 36 cases. The accuracy of preoperative CT in staging adenocarcinoma of the gastroesophageal junction is limited by its low sensitivity in detecting local invasion. Nodal size as measured with CT is not a reliable indicator of metastatic disease

  7. X-ray and CT signs of connective tissue dysplasia in patients with primarily diagnosed infiltrative pulmonary tuberculosis

    International Nuclear Information System (INIS)

    Sukhanova, L.A.; Sharmazanova, O.P.

    2009-01-01

    The x-ray signs of connective tissue systemic dysplasia (CTSD) in patients with primarily diagnosed pulmonary tuberculosis was investigated. Fifty-four patients (28 med and 26 women aged 18-70) with primarily diagnosed infiltrative pulmonary tuberculosis underwent x-ray study. In patients with infiltration pulmonary tuberculosis CTSD in the lungs manifests by their diminishing, deformity of the lung pattern, high position of the diaphragm cupola, mediastinum shift to the side of the pathology, which is better seen on CT. The degree of CTSD x-ray signs in the lungs depends on the number of phenotypical signs that is the degree of the disease manifestation. CT allows more accurate determining of the signs of connective tissue dysplasia in which tuberculosis develops

  8. The use of CT density changes at internal tissue interfaces to correlate internal organ motion with an external surrogate

    Energy Technology Data Exchange (ETDEWEB)

    Gaede, Stewart; Yu, Edward; Van Dyk, Jake; Battista, Jerry [Radiation Oncology Program, London Regional Cancer Program, London, Ontario (Canada); Carnes, Gregory; Lee, Ting-Yim [Department of Medical Biophysics, University of Western Ontario, London, Ontario (Canada)

    2009-01-21

    The purpose of this paper is to describe a non-invasive method to monitor the motion of internal organs affected by respiration without using external markers or spirometry, to test the correlation with external markers, and to calculate any time shift between the datasets. Ten lung cancer patients were CT scanned with a GE LightSpeed Plus 4-Slice CT scanner operating in a cine mode. We retrospectively reconstructed the raw CT data to obtain consecutive 0.5 s reconstructions at 0.1 s intervals to increase image sampling. We defined regions of interest containing tissue interfaces, including tumour/lung interfaces that move due to breathing on multiple axial slices and measured the mean CT number versus respiratory phase. Tumour motion was directly correlated with external marker motion, acquired simultaneously, using the sample coefficient of determination, r{sup 2}. Only three of the ten patients showed correlation higher than r{sup 2} = 0.80 between tumour motion and external marker position. However, after taking into account time shifts (ranging between 0 s and 0.4 s) between the two data sets, all ten patients showed correlation better than r{sup 2} = 0.8. This non-invasive method for monitoring the motion of internal organs is an effective tool that can assess the use of external markers for 4D-CT imaging and respiratory-gated radiotherapy on a patient-specific basis.

  9. Evaluation of solitary pulmonary nodules by integrated PET/CT: improved accuracy by FDG uptake pattern and CT findings

    International Nuclear Information System (INIS)

    Joon Young Choi; Kyung Soo Lee; O Jung Kwon; Young Mog Shim; Kyung-Han Lee; Yong Choi; Yearn Seong Choe; Byung-Tae Kim

    2004-01-01

    Objective: FDG PET is useful to differentiate malignancy from benign lesions in the evaluation of solitary pulmonary nodules (SPNs). However, FDG PET showed false positive results in benign inflammatory lesions such as tuberculosis and organizing pneumonia. Furthermore, malignant tumors such as adenocarcinoma (AC) with bronchioloalveolar carcinoma (BAC) type had lower FDG uptake than other cell types of non-small cell lung cancer. We investigated whether FDG uptake pattern and image findings of CT for attenuation correction could improve accuracy for evaluating SPNs over SUV in integrated PET/CT imaging using FDG. Methods: Forty patients (M:F = 23:17, mean age 58.2±9.4 yrs) with non-calcified SPNs (diameter on CT 30 mm, no significant mediastinal node enlargement, no atelectasis) were included. All subjects underwent integrated PET/CT imaging using FDG. One nuclear medicine physician and 1 chest radiologist interpreted the PET and non-contrast CT images for attenuation correction, respectively. On PET images, maximum SUV of SPN was acquired, and FDG uptake pattern was categorized as diffusely increased or heterogeneously increased with upper threshold of window setting adjusted to maximum SUV of each nodule. A radiologist interpreted SPNs as benign or malignant based on CT images with lung and mediastinai window settings blinded to PET findings. Results: On pathological exam, 30 SPNs were confirmed to be malignant (11 AC with non-BAC type, 8 AC with BAC type, 8 squamous cell carcinoma, 1 adenosquamous cell carcinoma, 1 neuroendocrine carcinoma, 1 large cell carcinoma), and 10 were benign (4 tuberculosis, 3 organizing pneumonia, 2 sclerosing pneumocytoma, 1 non-specific inflammation). All 5 nodules with max SUV 7.0 except one with tuberculoma had malignancy. When only nodules with diffusely increased uptake were considered malignant in indeterminate group with max SUV of 4.0 to 7.0, PET could diagnose 5 of 9 malignant nodules with one false positive nodule. In 6 of

  10. Hepatic perfusion during hepatic artery infusion chemotherapy: Evaluation with perfusion CT and perfusion scintigraphy

    International Nuclear Information System (INIS)

    Miller, D.L.; Carrasquillo, J.A.; Lutz, R.J.; Chang, A.E.

    1989-01-01

    The standard method for the evaluation of hepatic perfusion during hepatic artery infusion (HAI) chemotherapy is planar hepatic artery perfusion scintigraphy (HAPS). Planar HAPS was performed with 2 mCi of [99mTc] macroaggregated albumin infused at 1 ml/min and compared with single photon emission CT (SPECT) HAPS and with a new study, CT performed during the slow injection of contrast material through the HAI catheter (HAI-CT). Thirteen patients underwent 16 HAI-CT studies, 14 planar HAPS studies, and 9 SPECT HAPS studies. In 13 of 14 studies (93%) HAI-CT and planar HAPS were in complete agreement as to the perfusion pattern of intrahepatic metastases and normal liver. In nine studies where all modalities were performed, the findings identified by HAI-CT and planar HAPS agreed in all cases, whereas the results of two SPECT scans disagreed with the other studies. With respect to perfusion of individual metastases, 14 of 14 HAI-CT studies, 12 of 13 planar HAPS studies, and 9 of 9 SPECT HAPS studies correctly demonstrated the perfusion status of individual lesions as indicated by the pattern of changes in tumor size determined on CT obtained before and after the perfusion studies. Hepatic artery infusion CT was superior for delineation of individual metastases, particularly small lesions, and for the evaluation of nonperfused portions of the liver. Planar HAPS detected extrahepatic perfusion in four patients, and this was not detected by HAI-CT. We conclude that HAI-CT and scintigraphy are complementary techniques. Hepatic artery infusion CT has advantages for the evaluation of intrahepatic perfusion, and planar HAPS is superior to HAI-CT for the detection of extrahepatic perfusion

  11. Evaluation of thyroid tissue by Raman spectroscopy

    Science.gov (United States)

    Teixeira, C. S. B.; Bitar, R. A.; Santos, A. B. O.; Kulcsar, M. A. V.; Friguglietti, C. U. M.; Martinho, H. S.; da Costa, R. B.; Martin, A. A.

    2010-02-01

    Thyroid gland is a small gland in the neck consisting of two lobes connected by an isthmus. Thyroid's main function is to produce the hormones thyroxine (T4), triiodothyronine (T3) and calcitonin. Thyroid disorders can disturb the production of these hormones, which will affect numerous processes within the body such as: regulating metabolism and increasing utilization of cholesterol, fats, proteins, and carbohydrates. The gland itself can also be injured; for example, neoplasias, which have been considered the most important, causing damage of to the gland and are difficult to diagnose. There are several types of thyroid cancer: Papillary, Follicular, Medullary, and Anaplastic. The occurrence rate, in general is between 4 and 7%; which is on the increase (30%), probably due to new technology that is able to find small thyroid cancers that may not have been found previously. The most common method used for thyroid diagnoses are: anamnesis, ultrasonography, and laboratory exams (Fine Needle Aspiration Biopsy- FNAB). However, the sensitivity of those test are rather poor, with a high rate of false-negative results, therefore there is an urgent need to develop new diagnostic techniques. Raman spectroscopy has been presented as a valuable tool for cancer diagnosis in many different tissues. In this work, 27 fragments of the thyroid were collected from 18 patients, comprising the following histologic groups: goitre adjacent tissue, goitre nodular tissue, follicular adenoma, follicular carcinoma, and papillary carcinoma. Spectral collection was done with a commercial FTRaman Spectrometer (Bruker RFS100/S) using a 1064 nm laser excitation and Ge detector. Principal Component Analysis, Cluster Analysis, and Linear Discriminant Analysis with cross-validation were applied as spectral classification algorithm. Comparing the goitre adjacent tissue with the goitre nodular region, an index of 58.3% of correct classification was obtained. Between goitre (nodular region and

  12. Comparison of CT during arterial portography, delayed iodine CT, and MR imaging for the preoperative evaluation of hepatic tumors

    International Nuclear Information System (INIS)

    Nelson, R.C.; Chezmar, J.L.; Sugarbaker, P.H.; Bernardino, M.E.

    1988-01-01

    Twenty-eight patients with neoplastic involvement of the liver were studied with CT during arterial portography, delayed iodine CT, and MR imaging, to determine the number, size, and location of focal hepatic lesions prior to hepatic tumor surgery. The MR pulse-sequences used included T1- and T2-weighted spin-echo (SE) sequences and inversion-recovery (IR) sequences at 0.5 T, 1.5 T, or both. Results were compared with operative and pathologic findings. The sensitivities for the detection of individual focal lesions are as follows: CT during arterial portography, delayed iodine CT, 77%, IR at 0.5 T, 74%; T1-weighted SE at 0.5 T, 69%; T2-weighted SE at 1.5 T, 55%, IR at 1.5 T, 50%; T2-weighted SE at 0.5 T, 48%, and T1-weighted SE at 1.5 T, 31%. The positive predictive values ranged from 88% to 100% for all techniques. The authors' data suggest that CT during arterial portography is a superior technique for evaluating patients prior to hepatic tumor surgery

  13. CT digital radiography: Alternative technique for airway evaluation in physically disabled patients

    International Nuclear Information System (INIS)

    Mandell, G.A.; Harcke, H.T.; Brunson, G.; Delengowski, R.; Padman, R.

    1987-01-01

    Evaluation of the airway for the presence of granulation tissue prior to removal of a tracheostomy is essential to prevent sudden respiratory decompensation secondary to obstruction. Airway examination in a brain and/or spinal cord injured patient is especially difficult under fluoroscopy. The patient's lack of mobility results in poor visualization of the trachea, secondary to the overlying dense osseous components of the shoulders and thoracic cage. A CT localization view (digital view), which allows manipulation and magnification of the digital data in order to see the hidden airway and detect associated obstructing lesions, is proffered as an alternative technique to high KV, magnification technique. Thirteen examinations were performed satisfactorily in eleven patients examined by this technique with little expenditure of time, physical exertion, and irradiation. The sensitivity, specificity and accuracy of digital airway examination were 100%, 67% and 92% respectively with bronchoscopy used as the standard. (orig.)

  14. Utility of Electrocardiography (ECG)-Gated Computed Tomography (CT) for Preoperative Evaluations of Thymic Epithelial Tumors.

    Science.gov (United States)

    Ozawa, Yoshiyuki; Hara, Masaki; Nakagawa, Motoo; Shibamoto, Yuta

    2016-01-01

    Preoperative evaluation of invasion to the adjacent organs is important for the thymic epithelial tumors on CT. The purpose of our study was to evaluate the utility of electrocardiography (ECG)-gated CT for assessing thymic epithelial tumors with regard to the motion artifacts produced and the preoperative diagnostic accuracy of the technique. Forty thymic epithelial tumors (36 thymomas and 4 thymic carcinomas) were examined with ECG-gated contrast-enhanced CT using a dual source scanner. The scan delay after the contrast media injection was 30 s for the non-ECG-gated CT and 100 s for the ECG-gated CT. Two radiologists blindly evaluated both the non-ECG-gated and ECG-gated CT images for motion artifacts and determined whether the tumors had invaded adjacent structures (mediastinal fat, superior vena cava, brachiocephalic veins, aorta, pulmonary artery, pericardium, or lungs) on each image. Motion artifacts were evaluated using a 3-grade scale. Surgical and pathological findings were used as a reference standard for tumor invasion. Motion artifacts were significantly reduced for all structures by ECG gating ( p =0.0089 for the lungs and p ECG-gated CT and ECG-gated CT demonstrated 79% and 95% accuracy, respectively, during assessments of pericardial invasion ( p =0.03). ECG-gated CT reduced the severity of motion artifacts and might be useful for preoperative assessment whether thymic epithelial tumors have invaded adjacent structures.

  15. Evaluation of the robustness of the preprocessing technique improving reversible compressibility of CT images: Tested on various CT examinations

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Chang Ho; Kim, Bohyoung; Gu, Bon Seung; Lee, Jong Min [Department of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 300 Gumi-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-707 (Korea, Republic of); Kim, Kil Joong [Department of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 300 Gumi-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-707, South Korea and Department of Radiation Applied Life Science, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 110-799 (Korea, Republic of); Lee, Kyoung Ho [Department of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 300 Gumi-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-707, South Korea and Institute of Radiation Medicine, Seoul National University Medical Research Center, and Clinical Research Institute, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744 (Korea, Republic of); Kim, Tae Ki [Medical Information Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 300 Gumi-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-707 (Korea, Republic of)

    2013-10-15

    Purpose: To modify the preprocessing technique, which was previously proposed, improving compressibility of computed tomography (CT) images to cover the diversity of three dimensional configurations of different body parts and to evaluate the robustness of the technique in terms of segmentation correctness and increase in reversible compression ratio (CR) for various CT examinations.Methods: This study had institutional review board approval with waiver of informed patient consent. A preprocessing technique was previously proposed to improve the compressibility of CT images by replacing pixel values outside the body region with a constant value resulting in maximizing data redundancy. Since the technique was developed aiming at only chest CT images, the authors modified the segmentation method to cover the diversity of three dimensional configurations of different body parts. The modified version was evaluated as follows. In randomly selected 368 CT examinations (352 787 images), each image was preprocessed by using the modified preprocessing technique. Radiologists visually confirmed whether the segmented region covers the body region or not. The images with and without the preprocessing were reversibly compressed using Joint Photographic Experts Group (JPEG), JPEG2000 two-dimensional (2D), and JPEG2000 three-dimensional (3D) compressions. The percentage increase in CR per examination (CR{sub I}) was measured.Results: The rate of correct segmentation was 100.0% (95% CI: 99.9%, 100.0%) for all the examinations. The median of CR{sub I} were 26.1% (95% CI: 24.9%, 27.1%), 40.2% (38.5%, 41.1%), and 34.5% (32.7%, 36.2%) in JPEG, JPEG2000 2D, and JPEG2000 3D, respectively.Conclusions: In various CT examinations, the modified preprocessing technique can increase in the CR by 25% or more without concerning about degradation of diagnostic information.

  16. SU-G-JeP2-06: Dosimetric and Workflow Evaluation of First Commercial Synthetic CT Software for Clinical Use in Pelvis

    Energy Technology Data Exchange (ETDEWEB)

    Tyagi, N; Zhang, J; Happersett, L; Kadbi, M; Mechalakos, J; Deasy, J; Hunt, M [Memorial Sloan Kettering Cancer Center, New York, NY (United States)

    2016-06-15

    Purpose: evaluate a commercial synthetic CT (syn-CT) software for use in prostate radiotherapy Methods: Twenty prostate patients underwent CT and MR simulation scans in treatment position on a 3T Philips scanner. The MR protocol consisted of a T2w turbo spin-echo for soft tissue contrast, a 2D balanced-fast field echo (b-FFE) for fiducial identification, a dual-echo 3D FFE B0 map for distortion analysis and a 3D mDIXON FFE sequence to generate syn-CT. Two echoes are acquired during mDIXON scan, allowing water, fat, and in-phase images to be derived using the frequency shift of the fat and water protons. Tissues were classified as: air, adipose, water, trabecular/spongy bone and compact/cortical bone and assigned specific bulk HU values. Bone structures are segmented based on a pelvis bone atlas. Accuracy of syn-CT for patient treatment planning was analyzed by transferring the original plan and structures from the CT to syn-CT via rigid registration and recalculating dose. In addition, new IMRT plans were generated on the syn-CT using structures contoured on MR and transferred to the syn-CT. Accuracy of fiducial-based localization at the treatment machine performed using syn-CT or DRRs generated from syn-CT was assessed by comparing to orthogonal kV radiographs or CBCT. Results: Dosimetric comparison between CT and syn-CT was within 0.5% for all structures. The de-novo optimized plans generated on the syn-CT met our institutional clinical objectives for target and normal structures. Patient-induced susceptibility distortion based on B0 maps was within 1mm and 0.4 mm in the body and prostate. The rectal and bladder outlines on the syn-CT were deemed sufficient for assessing rectal and bladder filling on the CBCT at the time of treatment. CBCT localization showed a median error of < ±1 mm in LR, AP and SI direction. Conclusion: MRI derived syn-CT can be used clinically in MR-alone planning and treatment process for prostate. Drs. Deasy, Hunt and Tyagi have Master

  17. Soft tissue buccal carcinoma - a role of MDCT and PET/CT during the staging procedure

    International Nuclear Information System (INIS)

    Al-Amin, M.; Zlatareva, D.; Dineva, S.; Hadjidekov, V.; Kostadinova, I.; Al-Amin, B.

    2013-01-01

    Full text: Introduction: The incidence of buccal mucosa carcinoma is 8-10 % of cancers developing in the oral mucosa. Most often it develops on prior pre-neoplasia: leucoplakia, lichen. Characterized by painless in the early growth. The tumor is widely and quickly grows into the underlying tissues. Contracture are common. Histologically settled mostly squamous cell carcinoma and rarely glandular small salivary glands. What you will learn: A case study about a patient referred by a dentist with a painless swelling of the face on the right, with tightly - elastin texture appeared about 3 months ago is presented . Patient has difficulty swallowing, talking and breathing and limited mouth opening. Discussion: A MDCT study with intravenous contrast medium was performed for findings staging. It is found a heterodense tumor formation, involving the nasopharynx and oropharynx right without infiltration of main blood vessels with destruction of almost the entire branch of the mandible, with an interruption of the processus caronoideus integrity as well as the lateral wall and floor of the right maxillary sinus. The diagnose is buccal tumor formation in stage T4 N2V, Mx. The patient was referred to a specialized hospital for active treatment in maxillofacial surgery, where a biopsy was done and the histological result is: moderately differentiated buccal and gingival squamous cell carcinoma. From X-ray study of the lungs and heart several pulmonary nodules are identified and there is a possibility for metastatic lesions. Patient was referred for restaging and conducting whole body PET/CT. It is found a metabolically active tumor formation with data for regional lymphatic dissemination in the right. Conclusion: Squamous cell carcinoma is the most common cancer of the oral cavity (90-95 %). Buccal carcinoma represents 9.8% of cancer of the oral cavity and maxillofacial area. Treatment is complex. The five-year survival in T3 and T4 stages is 20-30%

  18. Evaluation of the efficiency of FDG PET/CT in detection and characterization of skeletal metastases

    Directory of Open Access Journals (Sweden)

    Ahmed Wafaie

    2014-03-01

    Conclusion: Fused PET/CT was highly efficient in evaluation of skeletal metastases with superior performance in: detection of early bone marrow infiltration not apparent on CT, resolution of metabolic activity before definite signs of complete healing on CT, detection of missed sclerotic metastases on PET due to their relatively low metabolic activity, detection of intra and extra osseous recurrence and differentiation of benign from malignant bone lesions.

  19. PET/CT imaging in response evaluation of patients with small cell lung cancer

    DEFF Research Database (Denmark)

    Fischer, Barbara M; Mortensen, Jann; Langer, Seppo W

    2006-01-01

    UNLABELLED: There is an increasing amount of evidence on the usability of PET in response evaluation of non-small cell lung cancer. However, data on SCLC is scarce and mainly retrospective. This prospective study assesses the use of PET (positron emission tomography) and PET/CT in response...... evaluation of patients with small cell lung cancer (SCLC). METHODS: Assignment of early and final response was compared between PET, PET/CT, and CT in 20 patients with SCLC. Final response as assigned by CT (RECIST) served as reference. RESULTS: At response evaluation after one cycle of chemotherapy major...... by PET/CT is feasible, but it is uncertain whether it adds further information to evaluation by RECIST, thus further studies and standardization of methods are needed....

  20. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... a follow-up exam is done because a potential abnormality needs further evaluation with additional views or ... detailed images of many types of tissue as well as the lungs, bones, and blood vessels. CT ...

  1. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... internal organs, bones, soft tissues and blood vessels. It may be used to help diagnose abdominal pain ... evaluate blood vessels throughout the body. With CT, it is possible to obtain very detailed pictures of ...

  2. Preoperative evaluation of the abdominal aortic aneurysm using spiral CT

    International Nuclear Information System (INIS)

    Chisuwa, Hisanao; Nishimaki, Keiji; Arai, Masayuki; Honda, Haruyasu; Urata, Koichi; Miyagawa, Yusuke; Makuuchi, Masatoshi; Shimizu, Mikio; Okamoto, Kohei.

    1995-01-01

    Six patients with abdominal aortic aneurysm (AAA) were studied with three-dimensionally reconstructed CT angiography (3D-CTA) in order to evaluate its usefulness as a diagnostic tool for vascular surgery patients. Images of the intravenously contrasted abdominal aorta were obtained with spiral scan during a single breath hold. The images of the abdominal aorta and its major branches were three-dimensionally reconstructed with a shaded surface display mode. The three-dimensional image reconstruction was successful in all the six cases and performed without difficulties. Shaded surface display presented a deficit to depict the aortic wall with mural thrombus. However, multidirectional display of the abdominal aorta and its branches facilitated interpretation of the anatomical details of the lesions and planning of surgical repair. 3D-CTA is an alternative to conventional aortography for preoperative diagnosis of AAA. Moreover it was shown to be noninvasive, easy to proceed. It presented good angiographical resolution that can be used as a precise diagnostic tool in vascular surgery. (author)

  3. Radiographic evaluation of dentigerous cyst with cone beam CT

    International Nuclear Information System (INIS)

    Park, Yong Chan; Lee, Wan; Lee, Byung Do

    2010-01-01

    The purpose of this study was to accurately analyze the radiographic characteristics of dentigerous cyst (DC) with multiplanar images of cone beam computed tomography (CBCT). Thirty eight radiographically and histopathologically proven cases of DCs were analyzed with panoramic radiograph and CBCT, retrospectively. The radiographic CT pattern, symmetry of radiolucency around the unerupted tooth crown, ratio of long length to short length, degree of cortical bone alternation, effects on adjacent tooth, and cyst size were analyzed. Relative frequencies of these radiographic features were evaluated. In order to compare the CBCT features of DC with those of odontogenic keratocyst (OKC), 9 cases of OKCs were analyzed with the same method radiographically. DCs consisted of thirty unilocular cases (79.0%), seven lobulated cases (18.4%) and one multilocular case (2.6%). Eight were asymmetric (21.0%) and thirty were symmetric (79.0%). Maxillary DC showed rounder shape than mandibular DC (L/S ratio; maxilla 1.32, mandible 1.67). Alternations of lingual cortical bone (14 cases, 48.2%) were more frequent than those of buccal side (7 cases, 24.1%). CBCT images of DC showed definite root resorption and bucco-lingual tooth displacement. These findings were hardly observed on panoramic radiographs of DCs. Comparison of CBCT features of DC with those of OKC showed several different features. CBCT images of DC showed various characteristic radiographic features. Therefore, CBCT can be helpful for the diagnosis of DC radiographically.

  4. Radiographic evaluation of dentigerous cyst with cone beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yong Chan; Lee, Wan; Lee, Byung Do [School of Dentisity, Wonkwang University, Iksan (Korea, Republic of)

    2010-09-15

    The purpose of this study was to accurately analyze the radiographic characteristics of dentigerous cyst (DC) with multiplanar images of cone beam computed tomography (CBCT). Thirty eight radiographically and histopathologically proven cases of DCs were analyzed with panoramic radiograph and CBCT, retrospectively. The radiographic CT pattern, symmetry of radiolucency around the unerupted tooth crown, ratio of long length to short length, degree of cortical bone alternation, effects on adjacent tooth, and cyst size were analyzed. Relative frequencies of these radiographic features were evaluated. In order to compare the CBCT features of DC with those of odontogenic keratocyst (OKC), 9 cases of OKCs were analyzed with the same method radiographically. DCs consisted of thirty unilocular cases (79.0%), seven lobulated cases (18.4%) and one multilocular case (2.6%). Eight were asymmetric (21.0%) and thirty were symmetric (79.0%). Maxillary DC showed rounder shape than mandibular DC (L/S ratio; maxilla 1.32, mandible 1.67). Alternations of lingual cortical bone (14 cases, 48.2%) were more frequent than those of buccal side (7 cases, 24.1%). CBCT images of DC showed definite root resorption and bucco-lingual tooth displacement. These findings were hardly observed on panoramic radiographs of DCs. Comparison of CBCT features of DC with those of OKC showed several different features. CBCT images of DC showed various characteristic radiographic features. Therefore, CBCT can be helpful for the diagnosis of DC radiographically.

  5. CT Perfusion evaluation of gastric cancer. Correlation with histologic type

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Ho; Joo, Ijin [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Kim, Se Hyung [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Han, Joon Koo [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of)

    2018-02-15

    To prospectively evaluate if the perfusion parameters of gastric cancer can provide information on histologic subtypes of gastric cancer. We performed preoperative perfusion CT (PCT) and curative gastrectomy in 46 patients. PCT data were analysed using a dedicated software program. Perfusion parameters were obtained by two independent radiologists and were compared according to histologic type using Kruskal-Wallis, Mann-Whitney U test and receiver operating characteristic analysis. To assess inter-reader agreement, we used intraclass correlation coefficient (ICC). Inter-reader agreement for perfusion parameters was moderate to substantial (ICC = 0.585-0.678). Permeability surface value of poorly cohesive carcinoma (PCC) was significantly higher than other histologic types (47.3 ml/100 g/min in PCC vs 26.5 ml/100 g/min in non-PCC, P < 0.001). Mean transit time (MTT) of PCC was also significantly longer than non-PCC (13.0 s in PCC vs 10.3 s in non-PCC, P = 0.032). The area under the curve to predict PCC was 0.891 (P < 0.001) for permeability surface and 0.697 (P = 0.015) for MTT. Obtaining perfusion parameters from PCT was feasible in gastric cancer patients and can aid in the preoperative imaging diagnosis of PCC-type gastric cancer as the permeability surface and MTT value of PCC type gastric cancer were significantly higher than those of non-PCC. (orig.)

  6. CT Perfusion evaluation of gastric cancer. Correlation with histologic type

    International Nuclear Information System (INIS)

    Lee, Dong Ho; Joo, Ijin; Kim, Se Hyung; Han, Joon Koo

    2018-01-01

    To prospectively evaluate if the perfusion parameters of gastric cancer can provide information on histologic subtypes of gastric cancer. We performed preoperative perfusion CT (PCT) and curative gastrectomy in 46 patients. PCT data were analysed using a dedicated software program. Perfusion parameters were obtained by two independent radiologists and were compared according to histologic type using Kruskal-Wallis, Mann-Whitney U test and receiver operating characteristic analysis. To assess inter-reader agreement, we used intraclass correlation coefficient (ICC). Inter-reader agreement for perfusion parameters was moderate to substantial (ICC = 0.585-0.678). Permeability surface value of poorly cohesive carcinoma (PCC) was significantly higher than other histologic types (47.3 ml/100 g/min in PCC vs 26.5 ml/100 g/min in non-PCC, P < 0.001). Mean transit time (MTT) of PCC was also significantly longer than non-PCC (13.0 s in PCC vs 10.3 s in non-PCC, P = 0.032). The area under the curve to predict PCC was 0.891 (P < 0.001) for permeability surface and 0.697 (P = 0.015) for MTT. Obtaining perfusion parameters from PCT was feasible in gastric cancer patients and can aid in the preoperative imaging diagnosis of PCC-type gastric cancer as the permeability surface and MTT value of PCC type gastric cancer were significantly higher than those of non-PCC. (orig.)

  7. CT coronary angiographic evaluation of suspected anginal chest pain.

    Science.gov (United States)

    Moss, Alastair J; Newby, David E

    2016-02-15

    Non-invasive imaging plays a critical role in the assessment of patients presenting with suspected angina chest pain. However, wide variations in practice across Europe and North America highlight the lack of consensus in selecting the appropriate first-line test for the investigation of coronary artery disease (CAD). CT coronary angiography (CTCA) has a high negative predictive value for excluding the presence of CAD. As such, it serves as a potential 'gatekeeper' to downstream testing by reducing the rate of inappropriate invasive coronary angiography. Two recent large multicentre randomised control trials have provided insights into whether CTCA can be incorporated into chest pain care pathways to improve risk stratification of CAD. They demonstrate that using CTCA enhances diagnostic certainty and improves the targeting of appropriate invasive investigations and therapeutic interventions. Importantly, reductions in cardiac death and non-fatal myocardial infarction appear to be attained through the more appropriate use of preventative therapy and coronary revascularisation when guided by CTCA. With this increasing portfolio of evidence, CTCA should be considered the non-invasive investigation of choice in the evaluation of patients with suspected angina pectoris due to coronary heart disease. NCT01149590, post-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  8. Use of CT in the evaluation of cochlear otosclerosis

    International Nuclear Information System (INIS)

    Mafee, M.F.; Valvassori, G.E.; Deitch, R.L.; Norouzi, P.; Henrikson, G.C.; Capek, V.; Applebaum, E.L.

    1985-01-01

    Otosclerosis (otospongiosis) occurs when the hard endochondral bone of the otic capsule is replaced by spongy vascular foci of haversian bone. Using computed tomography (CT), the authors studied the ears of 32 selected patients with mixed or sensorineural hearing loss; 24 were suspected of having otosclerosis. CT proved valuable in detecting cochlear otosclerosis, foci of demineralization, and changes in bony texture and enables the easy recognition of subtle radiographic findings. This paper also reports the CT findings of temporal bones in osteogenesis imperfecta and Paget disease

  9. CT Imaging for Evaluation of Calcium Crystal Deposition in the Knee: Initial Experience from The Multicenter Osteoarthritis (MOST) Study

    Science.gov (United States)

    Misra, Devyani; Guermazi, Ali; Sieren, Jered P.; Lynch, John; Torner, James; Neogi, Tuhina; Felson, David T.

    2014-01-01

    Objective Role of intra-articular calcium crystals in osteoarthritis (OA) is unclear. Imaging modalities used to date for its evaluation have limitations in their ability to fully characterize intra-articular crystal deposition. Since Computed Tomography (CT) imaging provides excellent visualization of bones and calcified tissue, in this pilot project we evaluated the utility of CT scan in describing intra-articular calcium crystal deposition in the knees. Method We included 12 subjects with and 4 subjects without radiographic chondrocalcinosis in the most recent visit from the Multicenter Osteoarthritis (MOST) study, which is a longitudinal cohort of community-dwelling older adults with or at risk for knee OA. All subjects underwent CT scans of bilateral knees. Each knee was divided into 25 subregions and each subregion was read for presence of calcium crystals by a musculoskeletal radiologist. To assess reliability, readings were repeated 4 weeks later. Results CT images permitted visualization of 25 subregions with calcification within and around the tibio-femoral and patello-femoral joints in all 24 knees with radiographic chondrocalcinosis. Intra-articular calcification was seen universally including meniscal cartilage (most common site involved in 21/24 knees), hyaline cartilage, cruciate ligaments, medial collateral ligament and joint capsule. Readings showed good agreement for specific tissues involved with calcium deposition (kappa: 0.70, 95% CI 0.62–0.80). Conclusion We found CT scan to be a useful and reliable tool for describing calcium crystal deposition in the knee and therefore potentially for studying role of calcium crystals in OA. We also confirmed that “chondrocalcinosis” is a misnomer because calcification is present ubiquitously. PMID:25451303

  10. The post-arthro-CT of the wrist: clinical evaluation

    International Nuclear Information System (INIS)

    Scheurecker, G.

    2001-03-01

    To compare the diagnostic effectiveness of post-arthro-CT (PACT) and 3-compartment wrist arthrography (AG) both separate and combined versus wrist arthroscopy for scapho-lunate ligament (SLL), luno-triquetral ligament (LTL) and triangular fibrocartilage (TFC) defects and chondromalacia of the carpal bones. Material and methods: In 58 patients (16-69 years) the affected wrist was examined initially by conventional 3-compartment wrist arthrography with digital subtraction technique during injection followed by digital stress images. Afterwards spiral arthro-CT was performed in the semi-coronal and axial plane with 1 mm slice thickness and secondary true-coronal and sagittal reconstructions. Within 1 month arthroscopy was performed in general anesthesia utilizing standard joint entry points combined with routine digital picture archiving. All examinations were evaluated for SLL, LTL and TFC defects, PACT and AS for ChM too. Results: AG versus AS: The following detection rates were observed (AG and AS positive/AG negative - AS positive/AG positive - AS negative/ AG and AS negative): SLL: 16/8/0/34, LTL: 13/4/8/33, TFC: 28/5/1/24. Using AS as the 'gold standard' this translates into following sensitivity (%) and specificity (%) values: SLL 67/100, LTL 76/80, TFC 85/96. PACT versus AS: The following detection rates were observed (PACT and AS positive/PACT negative - AS positive/PACT positive - AS negative/ PACT and AS negative): SLL: 18/6/0/34, LTL: 15/2/8/33, TFC: 31/2/2/23, ChM: 20/15/3/20. Using AS as the 'gold standard' this translates into following sensitivity (%) and specificity (%) values: SLL 75/100, LTL 88/80, TFC 94/92, ChM 57/87. AG+PACT versus AS: The following detection rates were observed (AG+PACT and AS positive/AG+PACT negative - AS positive/AG+PACT positive - AS negative/ AG+PACT and AS negative): SLL: 19/5/0/34, LTL: 15/2/8/33, TFC: 31/2/2/23, ChM 20/15/3/20. Using AS as the 'gold standard' this translates into following sensitivity (%) and specificity

  11. The post-arthro-CT of the wrist: clinical evaluation

    International Nuclear Information System (INIS)

    Scheurecker, G.

    2001-03-01

    To compare the diagnostic effectiveness of post-arthro-CT (PACT) and 3-compartment wrist arthrography (AG) both separate and combined versus wrist arthroscopy for scapho-lunate ligament (SLL), luno-triquetral ligament (LTL) and triangular fibrocartilage (TFC) defects and chondromalacia of the carpal bones. Material and methods: in 58 patients (16-69 years) the affected wrist was examined initially by conventional 3-compartment wrist arthrography with digital subtraction technique during injection followed by digital stress images. Afterwards spiral arthro-CT was performed in the semi-coronal and axial plane with 1 mm slice thickness and secondary true-coronal and sagittal reconstructions. Within 1 month arthroscopy was performed in general anesthesia utilizing standard joint entry points combined with routine digital picture archiving. All examinations were evaluated for SLL, LTL and TFC defects, PACT and AS for ChM too. Results: AG versus AS: the following detection rates were observed (AG and AS positive/AG negative - AS positive/AG positive - AS negative/ AG and AS negative): SLL: 16/8/0/34, LTL: 13/4/8/33, TFC: 28/5/1/24. Using AS as the 'gold standard' this translates into following sensitivity (%) and specificity (%) values: SLL 67/100, LTL 76/80, TFC 85/96. PACT versus AS: the following detection rates were observed (PACT and AS positive/PACT negative - AS positive/PACT positive - AS negative/ PACT and AS negative): SLL: 18/6/0/34, LTL: 15/2/8/33, TFC: 31/2/2/23, ChM: 20/15/3/20. Using AS as the 'gold standard' this translates into following sensitivity (%) and specificity (%) values: SLL 75/100, LTL 88/80, TFC 94/92, ChM 57/87. AG+PACT versus AS: the following detection rates were observed (AG+PACT and AS positive/AG+PACT negative - AS positive/AG+PACT positive - AS negative/ AG+PACT and AS negative): SLL: 19/5/0/34, LTL: 15/2/8/33, TFC: 31/2/2/23, ChM 20/15/3/20. Using AS as the 'gold standard' this translates into following sensitivity (%) and specificity

  12. Evaluation of pulmonary nodules and lung cancer with one-inch crystal gamma coincidence positron emission tomography/CT versus dedicated positron emission tomography/CT

    International Nuclear Information System (INIS)

    Moodie, K.; Lau, E.; Hicks, R. J.; Cherk, M. H.; Turlakow, A.; Skinner, S.; Kelly, M. J.; Kalff, V.

    2009-01-01

    Full text: Dedicated positron emission tomography (PET)/CT scanners using BGO and related detectors (d-PET) have become standard imaging instruments in many malignancies. Hybrid gamma camera systems using Nal detectors in coincidence mode (g-PET) have been compared to d-PET but reported usefulness has been variable when gamma cameras with half-inch to three-fourth-inch thick crystals have been used without CT. Our aim was to compare g-PET with a 1-in.-thick crystal and inbuilt CT for lesion localization and attenuation correction (g-PET/CT) and d-PET/CT in patients presenting with potential and confirmed lung malignancies. One hour after 18F-fluorodeoxyglucose (FDG), patients underwent BGO d-PET/CT from jaw to proximal thigh. This was followed by one to two bed position g-PET/CT 194 + 27 min after FDG. Each study pair was independently analysed with concurrent CT. d-PET/CT was interpreted by a radiologist experienced in both PET and CT, and g-PET/CT by consensus reading of an experienced PET physician and an experienced CT radiologist, A TNM score was assigned and studies were then unblinded and compared. Fifty-seven patients underwent 58 scan pairs over 2 years. Eighty-nine percent concordance was shown between g-PET/CT and d-PET/CT for the assessment of I intrapulmonary lesions, with 100% concordance for intrapulmonary lesions I >10 mm (36 of 36). Eighty-eight per cent (51 of 58) concordance was shown between g-PET/CTand d-PET/CTforTNM staging. Coincidence imaging usingan optimized dual-head 1-in.-thick crystal gamma camera with inbuilt CT compares reasonably well with dedicated PET/CT for evaluation of indeterminate pulmonary lesions and staging of pulmonary malignancies and may be of some] value when d-PET/CT is not readily available.

  13. An analysis of the NMR-CT image by the measurement of proton-relaxation times in tissue

    International Nuclear Information System (INIS)

    Naruse, Shoji; Horikawa, Yoshiharu; Tanaka, Chuzo; Hirakawa, Kimiyoshi; Nishikawa, Hiroyasu; Shimizu, Koji; Kiri, Motosada.

    1984-01-01

    NMR-CT images were analyzed by measuring the proton-relaxation times in tissues. The NMR-CT images were obtained in 10 normal volunteers and 16 patients with brain tumors with a prototype superconducting magnet (Shimadzu Corp., Japan) operating at 0.2 T and 0.375 T. A smooth T 1 relaxation curve was obtained in each part of the brain and the brain tumor by the use of the data of the NMR-CT image; consequently, the in vivo T 1 value was proved to be reliable. The in vivo T 1 value showed the specific value corresponding to each region of the normal brain in all cases. Cerebral gray matter normally had the longest T 1 value, followed by the medulla oblongata, the pons, and white matter. The T 1 value of each region of the brain varied to the same degree in proportion to the strength of the static magnetic field. The in vivo T 1 values of the brain tumor varied with the histological type. All were longer than any part of the brain parenchyma, being between 480 and 780 msec at 0.2 T. The prolongation of the T 1 value does not always correspond to the degree of the malignancy in a tumor. The in vitro T 1 and T 2 values were also prolonged in all tumors. Although the absolute value of T 1 did not coincide between the in vitro and in vivo data, the tendency of the prolongation was the same between them. This result indicated that the NMR-CT images could be analysed by the use of the data of the in vitro T 1 and T 2 values in the tumor tissues. It is important to analyse the NMR-CT image by both in vivo and in vitro examinations of the relaxation times. (J.P.N.)

  14. CT evaluation of complications of cryoablation treatment in lung cancer

    International Nuclear Information System (INIS)

    Zhu Caiqiao; Chen Yao; Zhang Zhitian; Su Jinzhan; Huang Zhen; Bao Kaikai

    2011-01-01

    Objective: To assess the complications of percutaneous targeted Argon-Helium cryoablation treatment in patients with lung cancer on CT. Methods: Ten patients with unresectable lung cancer were treated by cryotherapy under CT guidance with Argon-Helium cryoablation system. Dynamic contrast-enhanced CT was performed to assess changes before and after treatment, complications and treatment response. Results: Ice ball coverage immediately after surgery was satisfactory in all patients. There were a few complications including worsening hoarseness (1), small pneumothorax (1), and small amount of bleeding at the site of probe puncture (1). Conclusion: Percutaneous targeted Argon-Helium cryoablation guided by CT is an effective treatment for lung cancer without severe complications. (authors)

  15. Amyloid goiter in a child - US, CT and MR evaluation

    International Nuclear Information System (INIS)

    Perez Fontan, F.J.; Mosquera Oses, J.; Pombo Felipe, F.; Rodriguez Sanchez, I.; Arnaiz Pena, S.

    1992-01-01

    There are few radiological descriptions of amyloid goiter, basically in adult patients or oriental origin. We present a ten-year-old boy with Still's disease and secondary thyroid amyloidosis, describing the US, CT and MR findings. (orig.)

  16. The evaluation of atherosclerosis in coronary arteries with CT values

    International Nuclear Information System (INIS)

    Takemoto, Akiko

    1990-01-01

    In 50 patients with ischemic heart disease, X-ray computed tomography (CT) and coronary arteriography (CAG) were performed to compare CT values and CAG-proven stenosis in the left main trunk, left anterior descending, left circumflex, and right coronary artery. Luminal stenosis was graded as normal (no stenosis), minimal (between normal and significant), and significant (more than 50% in the left main trunk; more than 75% in the other arteries). CT values were significantly correlated with coronary artery stenosis; -5.4 in the normal group (71 arteries), +5.0 in the minimal group (63 arteries), and +31.8 in the significant group (51 arteries). In the normal group, CT values were independent of aging; -4.9 for patients younger than 50 years, -8.0 for those aged 50 to 59 years, and -0.4 for those more than 60 years. Increased CT values were associated with severer coronary artery disease shown on CAG. In determining significant coronary artery stenosis, CT values of more than 35 had a positive predictive value of 73.3%, a sensitivity of 43.1%, a specificity of 94.0%, an accuracy of 80.0%, and a likelihood ratio of 7.18. Measurement of CT values for the coronary arteries seems to be a noninvasive method for predicting significant stenosis. For patients younger than 60 years, high CT values even in a single artery seem to be associated with a high likelihood of significant stenosis and multivessel disease. (N.K.)

  17. Intrasplenic masses of ''preserved'' functioning splenic tissue in sickle cell disease: correlation of imaging findings (CT, ultrasound, MRI, and nuclear scintigraphy)

    International Nuclear Information System (INIS)

    Levin, T.L.; Berdon, W.E.; Haller, J.O.; Ruzal-Shapiro, C.; Hurlet-Jenson, A.

    1996-01-01

    Purpose. We studied six patients with sickle cell disease (SSD), five homozygous for sickle cell anemia and one with sickle beta-thalassemia, in whom rounded intrasplenic masses proved to be preserved functioning splenic tissue. Materials and methods. Available images including computed tomography, ultrasonography, bone scans (Tc-99m MDP), liver spleen scans (Tc-99m sulfur colloid), and MRI were evaluated. Results. The masses were low density on CT (in an otherwise calcified spleen), hypoechoic relative to the echogenic spleen on US, and had the imaging characteristics of normal spleen on MRI. They failed to accumulate Tc-99m MDP but did demonstrate uptake of Tc-99m sulfur colloid. Conclusion. In a patient with SSD and intrasplenic masses, proper correlation of multiple imaging modalities will establish the diagnosis of functioning splenic tissue and avoid mistaken diagnosis of splenic abscess or infarction. (orig.). With 2 figs., 1 tab

  18. Intrasplenic masses of ``preserved`` functioning splenic tissue in sickle cell disease: correlation of imaging findings (CT, ultrasound, MRI, and nuclear scintigraphy)

    Energy Technology Data Exchange (ETDEWEB)

    Levin, T.L. [Department of Radiology, Columbia-Presbyterian Medical Center, Babies and Children`s Hospital of New York, 3959 Broadway, BHN 3-318, New York, NY 10032 (United States); Berdon, W.E. [Department of Radiology, Columbia-Presbyterian Medical Center, Babies and Children`s Hospital of New York, 3959 Broadway, BHN 3-318, New York, NY 10032 (United States); Haller, J.O. [Department of Radiology, SUNY Downstate Medical Center, Brooklyn, New York (United States); Ruzal-Shapiro, C. [Department of Radiology, Columbia-Presbyterian Medical Center, Babies and Children`s Hospital of New York, 3959 Broadway, BHN 3-318, New York, NY 10032 (United States); Hurlet-Jenson, A. [Department of Pediatrics, Columbia-Presbyterian Medical Center, Babies and Children`s Hospital of New York, New York (United States)

    1996-09-01

    Purpose. We studied six patients with sickle cell disease (SSD), five homozygous for sickle cell anemia and one with sickle beta-thalassemia, in whom rounded intrasplenic masses proved to be preserved functioning splenic tissue. Materials and methods. Available images including computed tomography, ultrasonography, bone scans (Tc-99m MDP), liver spleen scans (Tc-99m sulfur colloid), and MRI were evaluated. Results. The masses were low density on CT (in an otherwise calcified spleen), hypoechoic relative to the echogenic spleen on US, and had the imaging characteristics of normal spleen on MRI. They failed to accumulate Tc-99m MDP but did demonstrate uptake of Tc-99m sulfur colloid. Conclusion. In a patient with SSD and intrasplenic masses, proper correlation of multiple imaging modalities will establish the diagnosis of functioning splenic tissue and avoid mistaken diagnosis of splenic abscess or infarction. (orig.). With 2 figs., 1 tab.

  19. Role of X-ray CT in the evaluation of extension of ovarian cancer

    International Nuclear Information System (INIS)

    Saito, Takashi

    1991-01-01

    To evaluate the utility of X-ray computed tomography (CT) in the management of malignant ovarian tumor, preoperative CT of 89 patients with ovarian cancer were analyzed on the basis of their surgically confirmed findings. Relationships between CT findings and clinical factors such as actual tumor spread, stage, and accomplished surgery were studied. The results obtained were as follows. The rates of correct diagnosis in tumor spread were 79.8% for tumor growth on the external surface of the ovary, 77.6% for involvement of both ovaries, 79.8% for ascites, 78.2% for metastasis to the uterus, 68.2% for peritoneal metastasis, 77.0% for metastasis to the intestine, and 79.3% for the metastasis to the omentum. Comparing the stage suggested by CT (CT stage) and the stage revealed by surgery (surgical stage), the stages coincided in 57 patients (64.0%). CT stages were overestimated in 9 caces and underestimated in 23 caces. As for the practicability of surgery, either complete or standard operation was performed in 31 of 33 caces (93.9%) of CT stage I, 21 of 28 (75.0%) of CT stage II, and 11 of 28 (39.3%) of CT stage III. The possibility of accomplishing surgery was very low when CT indicated stage III disease. (author)

  20. Pre-operative evaluation of cleft palate using three dimensional computerized tomography (s-D CT)

    International Nuclear Information System (INIS)

    Azia, A.; Hashmi, R.

    1999-01-01

    Cleft palate is a congenital anomaly with major development concerns. Surgery with bone grafting is often required to correct the lesion. With the introduction of 3-D CT the evaluation of cleft pa late has become more accurate. We present two cases of cleft palate, which were operated upon with bone grafting. We employed 3-D CT techniques in addition to the conventional 2-D CT, 3-D CT improves the estimation of the required bone graft and signification reduces length of surgery and complications. (author)

  1. Early evaluation of coronary artery bypass grafts: CT or selective angiography

    International Nuclear Information System (INIS)

    Wilson, P.C.; Gutierrez, O.; Moss, A.

    1984-01-01

    A prospective study was performed in 27 patients to compare the value of computed tomography and selective angiography in assessing coronary artery graft patency in the early post-operative period. The sensitivity of CT to graft patency was 85% with no falsely patent determinations. Dynamic CT was not found useful in predicting graft stenosis. There were no complications associated with CT studies, and two related to selective angiography. It is concluded that CT is the procedure of choice for graft evaluation in the early post-operative period; but that angiography is mandatory for the assessment of late symptom recurrence. A review is made of the results described in previous series. (orig.)

  2. Atheromatous extracranial carotid arteries: CT evaluation correlated with arteriography and pathologic examination

    International Nuclear Information System (INIS)

    Leeson, M.D.; Cacayorin, E.D.; Iliya, A.R.; Hodge, C.J.; Culebras, A.; Collins, G.H.; Kieffer, S.A.

    1985-01-01

    Dynamic, rapid sequence, axial computed tomography (CT) was employed to evaluate the extracranial common and internal carotid arteries in 17 patients with clinical histories suggesting recent or remote ischemia in the territory supplied by the internal carotid artery. The CT findings were correlated with arteriographic observations and with gross and histologic evaluations of endarterectomy specimens. Areas of arterial wall thickening were evaluated on CT scans with regard to both degree of thickening and radiographic density (attenuation). The degree of vessel wall thickening secondary to atheromatous plaque demonstrated on CT scans corresponded closely to the severity of luminal compromise seen on arteriograms. While arteriography provides information regarding the status of the arterial lumen, CT offers the potential of accurate characterization of pathologic changes in the wall of the extracranial carotid arteries in patients with symptoms of cerebral ischemia

  3. Low-Dose CT for Evaluation of Suspected Urolithiasis: Diagnostic Yield for Assessment of Alternative Diagnoses.

    Science.gov (United States)

    Weinrich, Julius Matthias; Bannas, Peter; Regier, Marc; Keller, Sarah; Kluth, Luis; Adam, Gerhard; Henes, Frank Oliver

    2018-03-01

    The purpose of this study is to assess the diagnostic yield of low-dose (LD) CT for alternative diagnoses in patients with suspected urolithiasis. In this retrospective study, we included 776 consecutive patients who underwent unenhanced abdominal CT for evaluation of suspected urolithiasis. All examinations were performed with an LD CT protocol; images were reconstructed using iterative reconstruction. The leading LD CT diagnosis was recorded for each patient and compared with the final clinical diagnosis, which served as the reference standard. The mean (± SD) effective dose of CT was 1.9 ± 0.6 mSv. The frequency of urolithiasis was 82.5% (640/776). LD CT reached a sensitivity of 94.1% (602/640), a specificity of 100.0% (136/136), and an accuracy of 95.1% (738/776) for the detection of urolithiasis. In 93 of 136 patients (68.4%) without urolithiasis, alternative diagnoses were established as the final clinical diagnoses. Alternative diagnoses were most commonly located in the genitourinary (n = 53) and gastrointestinal (n = 18) tracts. LD CT correctly provided alternative diagnoses for 57 patients (61.3%) and was false-negative for five patients (5.4%). The most common clinical alternative diagnoses were urinary tract infections (n = 22). Seven diagnoses missed at LD CT were located outside the FOV. For 43 of all 776 patients (5.5%), neither LD CT nor clinical workup could establish a final diagnosis. The sensitivity, specificity, and accuracy of LD CT for the detection of alternative diagnoses were 91.9% (57/62), 95.6% (43/45), and 93.5% (100/107), respectively. LD CT enables the diagnosis of most alternative diagnoses in the setting of suspected urolithiasis. The most frequent alternative diagnoses missed by LD CT are urinary tract infections or diagnoses located outside the FOV of the abdominopelvic CT scan.

  4. SU-E-J-218: Evaluation of CT Images Created Using a New Metal Artifact Reduction Reconstruction Algorithm for Radiation Therapy Treatment Planning

    Energy Technology Data Exchange (ETDEWEB)

    Niemkiewicz, J; Palmiotti, A; Miner, M; Stunja, L; Bergene, J [Lehigh Valley Health Network, Allentown, PA (United States)

    2014-06-01

    Purpose: Metal in patients creates streak artifacts in CT images. When used for radiation treatment planning, these artifacts make it difficult to identify internal structures and affects radiation dose calculations, which depend on HU numbers for inhomogeneity correction. This work quantitatively evaluates a new metal artifact reduction (MAR) CT image reconstruction algorithm (GE Healthcare CT-0521-04.13-EN-US DOC1381483) when metal is present. Methods: A Gammex Model 467 Tissue Characterization phantom was used. CT images were taken of this phantom on a GE Optima580RT CT scanner with and without steel and titanium plugs using both the standard and MAR reconstruction algorithms. HU values were compared pixel by pixel to determine if the MAR algorithm altered the HUs of normal tissues when no metal is present, and to evaluate the effect of using the MAR algorithm when metal is present. Also, CT images of patients with internal metal objects using standard and MAR reconstruction algorithms were compared. Results: Comparing the standard and MAR reconstructed images of the phantom without metal, 95.0% of pixels were within ±35 HU and 98.0% of pixels were within ±85 HU. Also, the MAR reconstruction algorithm showed significant improvement in maintaining HUs of non-metallic regions in the images taken of the phantom with metal. HU Gamma analysis (2%, 2mm) of metal vs. non-metal phantom imaging using standard reconstruction resulted in an 84.8% pass rate compared to 96.6% for the MAR reconstructed images. CT images of patients with metal show significant artifact reduction when reconstructed with the MAR algorithm. Conclusion: CT imaging using the MAR reconstruction algorithm provides improved visualization of internal anatomy and more accurate HUs when metal is present compared to the standard reconstruction algorithm. MAR reconstructed CT images provide qualitative and quantitative improvements over current reconstruction algorithms, thus improving radiation

  5. SU-E-J-218: Evaluation of CT Images Created Using a New Metal Artifact Reduction Reconstruction Algorithm for Radiation Therapy Treatment Planning

    International Nuclear Information System (INIS)

    Niemkiewicz, J; Palmiotti, A; Miner, M; Stunja, L; Bergene, J

    2014-01-01

    Purpose: Metal in patients creates streak artifacts in CT images. When used for radiation treatment planning, these artifacts make it difficult to identify internal structures and affects radiation dose calculations, which depend on HU numbers for inhomogeneity correction. This work quantitatively evaluates a new metal artifact reduction (MAR) CT image reconstruction algorithm (GE Healthcare CT-0521-04.13-EN-US DOC1381483) when metal is present. Methods: A Gammex Model 467 Tissue Characterization phantom was used. CT images were taken of this phantom on a GE Optima580RT CT scanner with and without steel and titanium plugs using both the standard and MAR reconstruction algorithms. HU values were compared pixel by pixel to determine if the MAR algorithm altered the HUs of normal tissues when no metal is present, and to evaluate the effect of using the MAR algorithm when metal is present. Also, CT images of patients with internal metal objects using standard and MAR reconstruction algorithms were compared. Results: Comparing the standard and MAR reconstructed images of the phantom without metal, 95.0% of pixels were within ±35 HU and 98.0% of pixels were within ±85 HU. Also, the MAR reconstruction algorithm showed significant improvement in maintaining HUs of non-metallic regions in the images taken of the phantom with metal. HU Gamma analysis (2%, 2mm) of metal vs. non-metal phantom imaging using standard reconstruction resulted in an 84.8% pass rate compared to 96.6% for the MAR reconstructed images. CT images of patients with metal show significant artifact reduction when reconstructed with the MAR algorithm. Conclusion: CT imaging using the MAR reconstruction algorithm provides improved visualization of internal anatomy and more accurate HUs when metal is present compared to the standard reconstruction algorithm. MAR reconstructed CT images provide qualitative and quantitative improvements over current reconstruction algorithms, thus improving radiation

  6. Synchrotron radiation μCT and histology evaluation of bone-to-implant contact.

    Science.gov (United States)

    Neldam, Camilla Albeck; Sporring, Jon; Rack, Alexander; Lauridsen, Torsten; Hauge, Ellen-Margrethe; Jørgensen, Henrik L; Jørgensen, Niklas Rye; Feidenhansl, Robert; Pinholt, Else Marie

    2017-09-01

    The purpose of this study was to evaluate bone-to-implant contact (BIC) in two-dimensional (2D) histology compared to high-resolution three-dimensional (3D) synchrotron radiation micro computed tomography (SR micro-CT). High spatial resolution, excellent signal-to-noise ratio, and contrast establish SR micro-CT as the leading imaging modality for hard X-ray microtomography. Using SR micro-CT at voxel size 5 μm in an experimental goat mandible model, no statistically significant difference was found between the different treatment modalities nor between recipient and reconstructed bone. The histological evaluation showed a statistically significant difference between BIC in reconstructed and recipient bone (p micro-CT evaluation a bias of 5.2% was found in reconstructed area, and 15.3% in recipient bone. We conclude that for evaluation of BIC with histology and SR micro-CT, SR micro-CT cannot be proven more precise than histology for evaluation of BIC, however, with this SR micro-CT method, one histologic bone section is comparable to the 3D evaluation. Further, the two methods complement each other with knowledge on BIC in 2D and 3D. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  7. Dependent lung opacity at thin-section CT: evaluation by spirometrically-gated CT of the influence of lung volume

    International Nuclear Information System (INIS)

    Lee, Ki Nam; Yoon, Seong Kuk; Sohn, Choon Hee; Choi, Pil Jo; Webb, W. Richard

    2002-01-01

    To evaluate the influence of lung volume on dependent lung opacity seen at thin-section CT. In thirteen healthy volunteers, thin-section CT scans were performed at three levels (upper, mid, and lower portion of the lung) and at different lung volumes (10, 30, 50, and 100% vital capacity), using spirometric gated CT. Using a three-point scale, two radiologists determined whether dependent opacity was present, and estimated its degree. Regional lung attenuation at a level 2 cm above the diaphragm was determined using semiautomatic segmentation, and the diameter of a branch of the right lower posterior basal segmental artery was measured at each different vital capacity. At all three anatomic levels, dependent opacity occurred significantly more often at lower vital capacities (10, 30%) than at 100% vital capacity (p = 0.001). Visually estimated dependent opacity was significantly related to regional lung attenuation (p < 0.0001), which in dependent areas progressively increased as vital capacity decreased (p < 0.0001). The presence of dependent opacity and regional lung attenuation of a dependent area correlated significantly with increased diameter of a segmental arterial branch (r = 0.493 and p = 0.0002; r = 0.486 and p 0.0003, respectively). Visual estimation and CT measurements of dependent opacity obtained by semiautomatic segmentation are significantly influenced by lung volume and are related to vascular diameter

  8. Evaluation of normal tissue responses to high-LET radiations

    International Nuclear Information System (INIS)

    Halnan, K.E.

    1979-01-01

    Clinical results presented have been analysed to evaluate normal tissue responses to high-LET radiations. Damage to brain, spinal cord, gut, skin, connective tissue and bone has occurred. A high RBE is probable for brain and possible for spinal cord and gut but other reasons for damage are also discussed. A net gain seems likely. Random controlled trials are advocated. (author)

  9. [Evaluation of new technologies PET/CT nuclear imaging].

    Science.gov (United States)

    Giraldes, Maria Rosário

    2010-01-01

    Nuclear imaging has used initially anatomic and volumetric technologies as CT or MRI. In recent years new dimensions of non invasive studies, as PET, have shown a higher utility in the effectiveness of the treatment. The evaluation of need must be done according to a principle of Horizontal Equity, equal treatment for equal need and of a principle of Vertical Equity, Different treatment, at regional level, according to each hospital level. The evaluation of need has been made according to the Potential Demand by Potential User Groups: diabetes, type 2, (50 years and more); screening colorectal (50 years and more); morbidity by cancer; surgery of lung cancer; cardiology; heart surgery; acute chest pain in the emergency department. In a Macro Perspective need has been evaluated using the Population Estimations for 2007, at municipality level. Relatively to Lisbon and Porto data at locality level has been used, from the 2001 Census. According to Campos, J.R. (2007), in 2006, it existed 1 PET by 1 million inhabitants and after that date 2 more were created (Quadrantes and Hospital ad Luz), belonging to the private sector. Mores 15 PET are needed in the NHS, 1 PET for about 504128 inhabitants. According to The Potential Demand perspective 18 new PET are needed, 15 from the public sector. The private sector will cover progressively the demand. Dorado and Albertino (2002), in Spain, mention that the introduction of this new technique in our Health System must be done slowly due to the cost and complexity. In Portugal exists already 6 PET and this applies also. As a first priority the intervention in Oncology in the IPO (Coimbra). A priority must be given to the University Hospitals of Santa Maria and São João. The Central Hospitals of Viseu and VilaReal/Régua must have also 1 PET. A priority must be given to the interior in order to avoid transports of patients and families. In fourth place the HC Central Lisbon must have also 1 PET, which will go to the New Hospital

  10. Comparison of plain radiography and CT in postoperative evaluation of ankle fractures

    International Nuclear Information System (INIS)

    Chen, Y.; Zhang, K.; Qiang, M.; Li, H.; Dai, H.

    2015-01-01

    Aim: To compare postoperative plain radiographs with computed tomography (CT) post-processing images in evaluating the quality of anatomical reduction and internal fixation of ankle fractures. Materials and methods: A total of 168 patients who sustained closed ankle fracture and were treated with open reduction and internal fixation in East Hospital were reviewed. Postoperative plain radiographs and CT post-processing images were evaluated. The observation was performed under volume-rendering mode and multiplanar reconstruction mode. The assessment was performed by two independent orthopaedic surgeons. The inter- and intra-observer variations were analysed by kappa statistics. The differences between plain radiographs and CT post-processing images were compared using χ 2 test (McNemar's test). Results: Inter- and intra-observer agreement was almost perfect (0.813–1.000) using CT post-processing images, which was higher than that using plain radiographs (0.323–0.848). More non-anatomical reduction could be recognised in the supination–external rotation (SER), supination–adduction (SAD), pronation–external rotation (PER), and overall groups (p<0.05) and more poor internal fixation could be recognised in the SER, SAD, and overall groups (p<0.05) using CT post-processing images than using radiographs. Conclusion: More residual articular step, fracture fragment displacement, and poor internal fixation could be detected by CT post-processing images than plain radiographs. -- Highlights: •We compared postoperative X-rays with CT images in ankle fractures. •The evaluation agreement using CT images was higher than X-rays. •CT images detect more residual articular steps than X-rays. •CT images detect more fracture fragment displacement than X-rays. •CT images detect more poor internal fixation than X-rays

  11. Helical CT in evaluation of the bronchial tree

    International Nuclear Information System (INIS)

    Perhomaa, M.; Laehde, S.; Rossi, O.; Suramo, I.

    1997-01-01

    Purpose: To establish a protocol for and to assess the value of helical CT in the imaging of the bronchial tree. Material and Methods: Noncontrast helical CT was performed in 30 patients undergoing fiberoptic bronchoscopy for different reasons. Different protocols were compared; they included overlapping 10 mm, 5 mm, or 3 mm slices and non-tilted, cephalad or caudal tilted images. Ordinary cross-sectional and multiplanar 2D reformats were applied for visualization of the bronchial branches. The effect of increasing the helical pitch was tested in one patient. Results: A total of 92.1-100% of the segmental bronchi present in the helical acquisitions were identified by the different protocols. The collimation had no significant impact on the identification of the bronchial branches, but utilization of 3-mm overlapping slices made it easier to distinguish the nearby branches and provided better longitudinal visualization of the bronchi in 2D reformats. The tilted scans illustrated the disadvantage of not covering all segmental bronchi in one breath-hold. An increase of the pitch from 1 to 1.5 did not cause noticeable blurring of the images. CT and bronchoscopic findings correlated well in the area accessible to bronchoscopy, but CT detected 5 additional pathological lesions (including 2 cancers) in the peripheral lung. Conclusion: Helical CT supplemented with bronchography-like 2D reformats provides an effective method complementary to bronchoscopy in the examination of the bronchial tree. (orig.)

  12. CT in the evaluation of patients on ECMO due to acute respiratory failure

    International Nuclear Information System (INIS)

    Lidegran, Marika; Jorulf, Haakan; Palmer, Kenneth; Linden, Viveka

    2002-01-01

    Heading AbstractBackground. In patients with acute severe respiratory failure (ARF) treated with extracorporeal membrane oxygenation (ECMO) the radiological evaluation has until now almost exclusively relied on bedside radiography and US. At St. Goeran/Karolinska ECMO centre CT has become a routine complement to bedside examinations.Objective. To review retrospectively the frequency, indications and findings on CT of patients with ARF on ECMO and to evaluate the risk of complications associated with transportation for CT examinations.Materials and methods. One hundred twelve neonates, children and adults were treated with ECMO from May 1994 to January 2001. Forty-six per cent of these patients had CT examinations on one or more occasions during ECMO, giving a total number of 238 examination sites on 104 occasions. All CT examinations were performed in the Paediatric Radiology Department and included a 10-min transport using a mobile ECMO system.Results. CT was more often performed in older patients and in patients with long ECMO runs. The main indications were suspected complications of ECMO and/or the underlying disease or a delay in clinical improvement. In 57% of the CT occasions, significant findings affecting treatment were revealed. There were no complications associated with the examinations or transport.Conclusions. CT is safe and useful in evaluation of patients with ARF during ECMO. (orig.)

  13. Atherosclerotic stenoses of renal arteries: Evaluation with CT

    International Nuclear Information System (INIS)

    Marteau, V.; Melki, J.P.; DuTemple, C.; Despres, E.; Taieb, A.

    1987-01-01

    Recent reports have shown that the long-term results of transluminal angioplasty (PTA) in renal arteries, performed to treat renovascular hypertension resulting from atherosclerotic disease, depended on the location, extent, and consistency of the obstructing lesions. Therefore, 30 patients shown with arteriography to have 40 atherosclerotic stenoses and five occlusions of the renal artery underwent CT for study of the walls of the aorta and renal arteries. CT easily demonstrates atherosclerotic lesions and seems better than arteriography when the lesions are ostial. It shows whether stenoses are calcified and also defines the lesions of the abdominal aorta, which is helpful when surgical bypass is considered. The paper presents the authors' preliminary findings. Long-term follow-up of these patients show if CT has a predictive value about PTA results

  14. Evaluation of effective dose from CT scans for overweight and obese adult patients using the VirtualDose software

    International Nuclear Information System (INIS)

    Liang, Baohui; Gao, Yiming; Chen, Zhi; Xu, X. George

    2017-01-01

    This paper evaluates effective dose (ED) of overweight and obese patients who undergo body computed tomography (CT) examinations. ED calculations were based on tissue weight factors in the International Commission on Radiological Protection Publication 103 (ICRP 103). ED per unit dose length product (DLP) are reported as a function of the tube voltage, body mass index (BMI) of patient. The VirtualDose software was used to calculate ED for male and female obese phantoms representing normal weight, overweight, obese 1, obese 2 and obese 3 patients. Five anatomic regions (chest, abdomen, pelvis, abdomen/pelvis and chest/abdomen/pelvis) were investigated for each phantom. The conversion factors were computed from the DLP, and then compared with data previously reported by other groups. It was observed that tube voltage and BMI are the major factors that influence conversion factors of obese patients, and that ED computed using ICRP 103 tissue weight factors were 24% higher for a CT chest examination and 21% lower for a CT pelvis examination than the ED using ICRP 60 factors. For body CT scans, increasing the tube voltage from 80 to 140 kVp would increase the conversion factors by as much as 19-54% depending on the patient's BMI. Conversion factor of female patients was ∼7% higher than the factors of male patients. DLP and conversion factors were used to estimate ED, where conversion factors depended on tube voltage, sex, BMI and tissue weight factors. With increasing number of obese individuals, using size-dependence conversion factors will improve accuracy, in estimating patient radiation dose. (authors)

  15. Evaluation of the Significance of Incidental Breast Lesions Detected by Chest CT

    International Nuclear Information System (INIS)

    Kim, Jae Hyun; Chang, Yun Woo; Hwang, Jung Hwa; Kim, Hyung Hwan; Lee, Eun Hye; Yang, Seung Boo

    2013-01-01

    To evaluate the significance of incidentally detected breast lesions on a chest CT scan. Thirty-six incidental breast lesions in 26 patients were detected on a chest CT scan and were correlated with breast sonography, retrospectively. Among them, twenty-four breast lesions in 20 patients that were correlated with chest CT and sonography were available to pathology or follow up sonography. The CT findings were compared with sonographic findings according to the pathologic results. Incidentally detected breast lesions on a chest CT scan were correlated with sonography in 86% (31/36). Among 24 lesions that were available to pathology or follow up sonography, seven (29.2%) lesions were malignant and 17 (70.8%) lesions were benign. CT revealed a significant difference between benign and malignant lesions in terms of shape and margin (p = 0.007; p = 0.008, respectively). The CT findings were well correlated with sonographic findings in shape and margin (p = 0.001, respectively). Incidentally detected breast lesions on chest CT can be correlated with sonography. An irregular shape or a non-circumscribed margin of breast lesions on a CT scan can be considered as a suggestive sign of malignancy.

  16. Utility of CT in the evaluation of pulmonary tuberculosis in patients without Aids

    International Nuclear Information System (INIS)

    Lee, K.S.; Hwang, J.W.; Chung, M.P.

    1997-01-01

    Objective. To assess the utility of CT in the evaluation of pulmonary tuberculosis in patients without AIDS. Patients and methods. Thin-section CT scans for suspicion of pulmonary tuberculosis were obtained from 226 patients. A total of 38 patients were excluded; the reasons were unavailability of final results (n=18), patient unavailability for follow-up (n=13), and coexistence of tuberculosis and aspergilloma (n=7). The results from 188 patients were used for this study. After assessing the patterns of parenchymal lesion, involved segments, and presence of cavity, bronchiectases, and bronchogenic spread of the lesion with CT, tentative diagnosis and disease activity were recorded. Results. With CT, 133 of 146 patients (91%) with tuberculosis were correctly diagnosed as having pulmonary tuberculosis whereas 32 of 42 patients (76%) without tuberculosis were correctly excluded. CT diagnosis of lung cancer (n=8), bacterial pneumonia (n=2), pulmonary metastasis (n=1), chronic hypersensitivity pneumonia (n=1) and diffuse pan-bronchiolitis (n=1) turned out to be tuberculosis. Conversely CT diagnoses of tuberculosis appeared pathologically as lung cancer (n=5), bacterial pneumonia 71/89, 80%) and inactive state (51/57, 89%) of disease respectively could be correctly differentiated by CT. Conclusion. CT can be helpful in the diagnosis of pulmonary tuberculosis in most cases. On the basis of CT findings, distinction of active from inactive disease can be made in most cases. (authors)

  17. CT evaluation of the kidneys following extracorporeal shock wave lithotripsy

    International Nuclear Information System (INIS)

    Rubin, J.I.; Arger, P.H.; Pollack, H.M.; Banner, M.P.; Coleman, B.G.; Mintz, M.C.; Van Arsdalen, K.N.

    1986-01-01

    CT scans of the kidneys were obtained iln 50 patients before and after extracorporeal shock wave lithotripsy (ESWL). Post-ESWL scans demonstrated subcapsular hematomas in eight (15%) and intrarenal hematomas in two (4%) patients. Water-density subcapsular collections were seen in three (6%) patients. Treated kidneys showed a mean increase in renal size of 9%. Perinephric stranding and fascial thickening were seen in 37 (70%) of 53 treated renal fossae. While most patients undergoing ESWL will show some posttreatment abnormality on CT, the procedure appears to be associated with a low incidence of serious renal trauma

  18. CT evaluation of optic nerve compression in thyroid eye disease

    International Nuclear Information System (INIS)

    Barrett, L.; Giatt, H.J.; Burde, R.M.; Gado, M.

    1986-01-01

    In thyroid eye disease, visual loss due to optic nerve compression by enlarged muscles near the orbital apex requires prompt surgical decompression and must be differentiated from visual loss due to other mechanisms. Seventy-two high-resolution orbital CT scans of patients with thyroid eye disease were analyzed. From a coronal reconstruction, an easily measured ''apical index'' was determined. Average apical indices for orbits without optic neuropathy (41.0%) and with optic neuropathy (70.2%) were significantly different (P < .001). With the aid of the apical index, CT findings can be used to predict which patients with thyroid eye disease have optic nerve compression

  19. Normal bone and soft tissue distribution of fluorine-18-sodium fluoride and artifacts on 18F-NaF PET/CT bone scan: a pictorial review.

    Science.gov (United States)

    Sarikaya, Ismet; Elgazzar, Abdelhamid H; Sarikaya, Ali; Alfeeli, Mahmoud

    2017-10-01

    Fluorine-18-sodium fluoride (F-NaF) PET/CT is a relatively new and high-resolution bone imaging modality. Since the use of F-NaF PET/CT has been increasing, it is important to accurately assess the images and be aware of normal distribution and major artifacts. In this pictorial review article, we will describe the normal uptake patterns of F-NaF in the bone tissues, particularly in complex structures, as well as its physiologic soft tissue distribution and certain artifacts seen on F-NaF PET/CT images.

  20. An evaluation on CT image acquisition method for medical VR applications

    Science.gov (United States)

    Jang, Seong-wook; Ko, Junho; Yoo, Yon-sik; Kim, Yoonsang

    2017-02-01

    Recent medical virtual reality (VR) applications to minimize re-operations are being studied for improvements in surgical efficiency and reduction of operation error. The CT image acquisition method considering three-dimensional (3D) modeling for medical VR applications is important, because the realistic model is required for the actual human organ. However, the research for medical VR applications has focused on 3D modeling techniques and utilized 3D models. In addition, research on a CT image acquisition method considering 3D modeling has never been reported. The conventional CT image acquisition method involves scanning a limited area of the lesion for the diagnosis of doctors once or twice. However, the medical VR application is required to acquire the CT image considering patients' various postures and a wider area than the lesion. A wider area than the lesion is required because of the necessary process of comparing bilateral sides for dyskinesia diagnosis of the shoulder, pelvis, and leg. Moreover, patients' various postures are required due to the different effects on the musculoskeletal system. Therefore, in this paper, we perform a comparative experiment on the acquired CT images considering image area (unilateral/bilateral) and patients' postures (neutral/abducted). CT images are acquired from 10 patients for the experiments, and the acquired CT images are evaluated based on the length per pixel and the morphological deviation. Finally, by comparing the experiment results, we evaluate the CT image acquisition method for medical VR applications.

  1. Synchrotron radiation μCT and histology evaluation of bone-to-implant contact

    DEFF Research Database (Denmark)

    Neldam, Camilla Albeck; Sporring, Jon; Rack, Alexander

    2017-01-01

    The purpose of this study was to evaluate bone-to-implant contact (BIC) in two-dimensional (2D) histology compared to high-resolution three-dimensional (3D) synchrotron radiation micro computed tomography (SR micro-CT). High spatial resolution, excellent signal-to-noise ratio, and contrast...... establish SR micro-CT as the leading imaging modality for hard X-ray microtomography. Using SR micro-CT at voxel size 5 μm in an experimental goat mandible model, no statistically significant difference was found between the different treatment modalities nor between recipient and reconstructed bone....... Comparing histology and SR micro-CT evaluation a bias of 5.2% was found in reconstructed area, and 15.3% in recipient bone. We conclude that for evaluation of BIC with histology and SR micro-CT, SR micro-CT cannot be proven more precise than histology for evaluation of BIC, however, with this SR micro-CT...

  2. Adrenergic pathway activation enhances brown adipose tissue metabolism: A [18 F]FDG PET/CT study in mice

    International Nuclear Information System (INIS)

    Mirbolooki, M. Reza; Upadhyay, Sanjeev Kumar; Constantinescu, Cristian C.; Pan, Min-Liang; Mukherjee, Jogeshwar

    2014-01-01

    Objective: Pharmacologic approaches to study brown adipocyte activation in vivo with a potential of being translational to humans are desired. The aim of this study was to examine pre- and postsynaptic targeting of adrenergic system for enhancing brown adipose tissue (BAT) metabolism quantifiable by [ 18 F]fluoro-2-deoxyglucose ([ 18 F]FDG) positron emission tomography (PET)/computed tomography (CT) in mice. Methods: A β 3 -adrenoreceptor selective agonist (CL 316243), an adenylyl cyclase enzyme activator (forskolin) and a potent blocker of presynaptic norepinephrine transporter (atomoxetine), were injected through the tail vein of Swiss Webster mice 30 minutes before intravenous (iv) administration of [ 18 F]FDG. The mice were placed on the PET/CT bed for 30 min PET acquisition followed by 10 min CT acquisition for attenuation correction and anatomical delineation of PET images. Results: Activated interscapular (IBAT), cervical, periaortic and intercostal BAT were observed in 3-dimentional analysis of [ 18 F]FDG PET images. CL 316243 increased the total [ 18 F]FDG standard uptake value (SUV) of IBAT 5-fold greater compared to that in placebo-treated mice. It also increased the [ 18 F]FDG SUV of white adipose tissue (2.4-fold), and muscle (2.7-fold), as compared to the control. There was no significant difference in heart, brain, spleen and liver uptakes between groups. Forskolin increased [ 18 F]FDG SUV of IBAT 1.9-fold greater than that in placebo-treated mice. It also increased the [ 18 F]FDG SUV of white adipose tissue (2.2-fold) and heart (5.4-fold) compared to control. There was no significant difference in muscle, brain, spleen, and liver uptakes between groups. Atomoxetine increased [ 18 F]FDG SUV of IBAT 1.7-fold greater than that in placebo-treated mice. There were no significant differences in all other organs compared to placebo-treated mice except liver (1.6 fold increase). A positive correlation between SUV levels of IBAT and CT Hounsfield unit (HU

  3. CT evaluation of the bile ducts in patients with fatty liver

    International Nuclear Information System (INIS)

    Quint, L.E.; Glazer, G.M.

    1984-01-01

    Computed tomographic (CT) evaluation of the bile ducts in the fatty liver can be difficult, since hepatic attenuation decreases with increased triglyceride content, and liver parenchyma may become isodense with bile. Forty-seven patients with fatty infiltration of the liver were retrospectively identified. In 7 of these patients, attenuation of liver and bile differed by less than 10 HU. In 2 patients, dilated intrahepatic ducts were invisible using CT, because bile was isodense with fatty liver parenchyma. Thus, the fatty liver presents a potential pitfall in CT evaluation of the bile ducts. For maximal accuracy scans should be obtained both before and after administration of intravenous urographic contrast material

  4. PET for the evaluation of pleural thickening observed on CT

    NARCIS (Netherlands)

    Kramer, H; Pieterman, RM; Slebos, DJ; Timens, W; Vaalburg, W; Koeter, GH; Groen, HJM

    Early discrimination between benign and malignant pleural diseases is vital for the treatment and prognosis of a patient. Imaging is traditionally performed with CT or MRI, with an accuracy of 50%-75%. PET has proven to be superior as a diagnostic tool in several malignancies. In this prospective

  5. The missing eyeball-CT evaluation (a case report

    Directory of Open Access Journals (Sweden)

    Raghav B

    1991-01-01

    Full Text Available A case of blow out fracture of the medial wall and floor of the orbit with herniation of the eyeball into the ethmoid sinus diagnosed on CT scan is reported. To the best of our knowledge there is no previous report of prolapse of eyeball into the ethmoid sinus.

  6. An evaluation of in-plane shields during thoracic CT.

    Science.gov (United States)

    Foley, S J; McEntee, M F; Rainford, L A

    2013-08-01

    The object of this study was to compare organ dose and image quality effects of using bismuth and barium vinyl in-plane shields with standard and low tube current thoracic CT protocols. A RANDO phantom was scanned using a 64-slice CT scanner and three different thoracic protocols. Thermoluminescent dosemeters were positioned in six locations to record surface and absorbed breast and lung doses. Image quality was assessed quantitatively using region of interest measurements. Scanning was repeated using bismuth and barium vinyl in-plane shields to cover the breasts and the results were compared with standard and reduced dose protocols. Dose reductions were most evident in the breast, skin and anterior lung when shielding was used, with mean reductions of 34, 33 and 10 % for bismuth and 23, 18 and 11 % for barium, respectively. Bismuth was associated with significant increases in both noise and CT attenuation values for all the three protocols, especially anteriorly and centrally. Barium shielding had a reduced impact on image quality. Reducing the overall tube current reduced doses in all the locations by 20-27 % with similar increases in noise as shielding, without impacting on attenuation values. Reducing the overall tube current best optimises dose with minimal image quality impact. In-plane shields increase noise and attenuation values, while reducing anterior organ doses primarily. Shielding remains a useful optimisation tool in CT and barium is an effective alternative to bismuth especially when image quality is of concern.

  7. Unenhanced multidetector CT (CT KUB) in the initial imaging of suspected acute renal colic: evaluating a new service

    International Nuclear Information System (INIS)

    Chowdhury, F.U.; Kotwal, S.; Raghunathan, G.; Wah, T.M.; Joyce, A.; Irving, H.C.

    2007-01-01

    Aim: To evaluate a new imaging pathway for the investigation of patients presenting with suspected acute renal colic. Materials and methods: A retrospective review of 500 consecutive cases of suspected acute renal colic was undertaken to evaluate the initial results of a new imaging pathway introduced at our institution, which completely replaced the intravenous urogram (IVU) with unenhanced multidetector CT (CT KUB). Results: The positive rate for urolithiasis was 44% (221/500), the negative rate 46% (229/500) and the rate of other significant findings was 12% (59/500). Female patients had a low positive rate compared with male patients (27.5 versus 57.5%; p < 0.001). Urological intervention was required in 28% (61/221) and these patients had a larger average stone size (6.6 versus 3.7 mm; p < 0.001) and the stone was located more proximally. Out-of-hours imaging was performed in 37% (186/500), and these patients had a higher positive rate (52 versus 40%; p < 0.001). Other findings included a wide range of acute non-urological conditions. Conclusion: The feasibility of replacing the acute IVU with CT KUB in the initial assessment of suspected acute renal colic was demonstrated in the present study. The technique enables rapid diagnosis of urolithiasis, stratification of patients likely to proceed to urological intervention, and prompt diagnosis of a variety of other acute pathological conditions

  8. CT in the evaluation of severe liver trauma; Tomografia computadorizada na avaliacao do trauma hepatico grave

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Marcel Autran C. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina, Hospital das Clinicas; Souza Rocha, Manoel de; Machado, Manoel C.C. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina; Macedo Neto, Augusto Cesar de; Maciel, Rosangela Pereira; Simonetti, Celso

    1995-05-01

    Abdominal CT is a common examination in the evaluation of patients with blunt abdominal trauma and clinical suspicion for solid organ injury when reasons for immediate laparotomy are not present. A case of major blunt hepatic injury in a 22-year-old patient is reported. The authors present a brief review of the literature and discussion about the role of CT scan in the evaluation of hepatic trauma, surgical planning and postoperative follow-up. (author). 15 refs., 3 figs., 1 tab.

  9. PET attenuation coefficients from CT images: experimental evaluation of the transformation of CT into PET 511-keV attenuation coefficients.

    Science.gov (United States)

    Burger, C; Goerres, G; Schoenes, S; Buck, A; Lonn, A H R; Von Schulthess, G K

    2002-07-01

    The CT data acquired in combined PET/CT studies provide a fast and essentially noiseless source for the correction of photon attenuation in PET emission data. To this end, the CT values relating to attenuation of photons in the range of 40-140 keV must be transformed into linear attenuation coefficients at the PET energy of 511 keV. As attenuation depends on photon energy and the absorbing material, an accurate theoretical relation cannot be devised. The transformation implemented in the Discovery LS PET/CT scanner (GE Medical Systems, Milwaukee, Wis.) uses a bilinear function based on the attenuation of water and cortical bone at the CT and PET energies. The purpose of this study was to compare this transformation with experimental CT values and corresponding PET attenuation coefficients. In 14 patients, quantitative PET attenuation maps were calculated from germanium-68 transmission scans, and resolution-matched CT images were generated. A total of 114 volumes of interest were defined and the average PET attenuation coefficients and CT values measured. From the CT values the predicted PET attenuation coefficients were calculated using the bilinear transformation. When the transformation was based on the narrow-beam attenuation coefficient of water at 511 keV (0.096 cm(-1)), the predicted attenuation coefficients were higher in soft tissue than the measured values. This bias was reduced by replacing 0.096 cm(-1) in the transformation by the linear attenuation coefficient of 0.093 cm(-1) obtained from germanium-68 transmission scans. An analysis of the corrected emission activities shows that the resulting transformation is essentially equivalent to the transmission-based attenuation correction for human tissue. For non-human material, however, it may assign inaccurate attenuation coefficients which will also affect the correction in neighbouring tissue.

  10. Technical Evaluation Report 41: WebCT: A major shift of emphasis

    Directory of Open Access Journals (Sweden)

    Kristine Thibeault

    2004-11-01

    Full Text Available The evaluation reports in this series usually feature several products at once. The current review, however, comes at a time when one of the most widely used (and expensive online learning management systems is undergoing a major change in its marketing strategy and corporate focus. WebCT is currently evolving to a new version (WebCT Vista, with much attendant discussion by distance education (DE users. The current review, as the others in this series, adds the DE student's perspective to this discussion. The review compares the existing WebCT Campus Edition with the new WebCT Vista, and examines some of the problems associated with the migration to Vista at the institutional level. A response to the report by the WebCT company is appended.

  11. Performance evaluation of 8 CT scanners for clinical use in Italy

    International Nuclear Information System (INIS)

    Pinto, I.; De Denaro, M.; Giribona, P.; Gicericin, C.; Bravar, D.

    1988-01-01

    In the past few years the use of CT scanners has widely spread in Italian care institutions. This methodology has thus become an important creates the need for an accurate study of the various aspects of the phenomenon, e.g. technological, diagnostic and economic. In order to evaluate the quality of the CT scanners used in our country, the majors suppliers of the Italian market were asked to provide us with a unit from their production. Six out of 7 companies complied with our request. A standard protocol was used to evaluate the performance of 8 CT scanners, currently used in Italy. The following parameters were evaluated: spatial resolution, contrast resolution, noise, slice thickness, uniformity, linearity and radiation dose. Five currently-used operating modalities were employed. The results allow an overall assessment of the performance of the 8 CT scanners

  12. The value of spiral CT and image post-processing in the evaluation of laryngeal carcinoma

    International Nuclear Information System (INIS)

    Wang Jianwei; Wu Ning; Luo Dehong

    2001-01-01

    Objective: To access the value of the combination of axial image, MPR, and VE in the evaluation of laryngeal carcinoma involvement. Methods: Twenty patients with laryngeal carcinoma or hypopharyngeal carcinoma were prospectively studied by helical CT, and MPR and VE were subsequently done on the Voxel Q workstation. The axial images finding and the combined image findings of axial image, MPR, and VE were compared with the pathological results by using a predetermined checklist of 17 regions according to the TNM classification of malignant tumors (UICC and AJCC). The results were studied in a blind way. Results: In the evaluation of the neoplastic invasion of ventricular fold, vocal cord, the anterior commissure, subglottic region, thyroid cartilage, and tissue beyond the larynx, the combined image were better than axial image in sensitivity (100% vs 92.4%, P = 0.064), specificity (98.5% vs 89.5%, P = 0.028), and accuracy (99.2% vs 90.8%, P0.003). Neoplastic invasion of the arytenoid cartilage was present in 6 patients. The sensitivity and the specificity was 83.3% and 100% respectively when using the criteria of the arytenoid cartilage sclerosing combined with distortion, erosion or lysis. The specificity was only 57.1% when using the criteria of arytenoid cartilage sclerosing for judging parameter. The result was identical when assessing the arytenoid cartilage, PGS, and PES between the two groups. Conclusion: Axial image combined with subsequent MPR and VE could improve the diagnosis in the evaluation of the neoplastic invasion of ventricular fold, vocal cord, the anterior commissure, subglottic region, thyroid cartilage, and tissue beyond the larynx

  13. SU-E-J-106: The Use of Deformable Image Registration with Cone-Beam CT for a Better Evaluation of Cumulative Dose to Organs

    Energy Technology Data Exchange (ETDEWEB)

    Fillion, O; Gingras, L; Archambault, L [Universite Laval, Quebec, Quebec (Canada); Centre de recherche du CHU de Quebec, Quebec, Quebec (Canada); Centre de recherche sur le cancer, Quebec, Quebec (Canada)

    2015-06-15

    Purpose: The knowledge of dose accumulation in the patient tissues in radiotherapy helps in determining the treatment outcomes. This project aims at providing a workflow to map cumulative doses that takes into account interfraction organ motion without the need for manual re-contouring. Methods: Five prostate cancer patients were studied. Each patient had a planning CT (pCT) and 5 to 13 CBCT scans. On each series, a physician contoured the prostate, rectum, bladder, seminal vesicles and the intestine. First, a deformable image registration (DIR) of the pCTs onto the daily CBCTs yielded registered CTs (rCT) . This rCT combined the accurate CT numbers of the pCT with the daily anatomy of the CBCT. Second, the original plans (220 cGy per fraction for 25 fractions) were copied on the rCT for dose re-calculation. Third, the DIR software Elastix was used to find the inverse transform from the rCT to the pCT. This transformation was then applied to the rCT dose grid to map the dose voxels back to their pCT location. Finally, the sum of these deformed dose grids for each patient was applied on the pCT to calculate the actual dose delivered to organs. Results: The discrepancy between the planned D98 and D2 and these indices re-calculated on the rCT, are, on average, of −1 ± 1 cGy and 1 ± 2 cGy per fraction, respectively. For fractions with large anatomical motion, the D98 discrepancy on the re-calculated dose grid mapped onto the pCT can raise to −17 ± 4 cGy. The obtained cumulative dose distributions illustrate the same behavior. Conclusion: This approach allowed the evaluation of cumulative doses to organs with the help of uncontoured daily CBCT scans. With this workflow, the easy evaluation of doses delivered for EBRT treatments could ultimately lead to a better follow-up of prostate cancer patients.

  14. SU-E-J-106: The Use of Deformable Image Registration with Cone-Beam CT for a Better Evaluation of Cumulative Dose to Organs

    International Nuclear Information System (INIS)

    Fillion, O; Gingras, L; Archambault, L

    2015-01-01

    Purpose: The knowledge of dose accumulation in the patient tissues in radiotherapy helps in determining the treatment outcomes. This project aims at providing a workflow to map cumulative doses that takes into account interfraction organ motion without the need for manual re-contouring. Methods: Five prostate cancer patients were studied. Each patient had a planning CT (pCT) and 5 to 13 CBCT scans. On each series, a physician contoured the prostate, rectum, bladder, seminal vesicles and the intestine. First, a deformable image registration (DIR) of the pCTs onto the daily CBCTs yielded registered CTs (rCT) . This rCT combined the accurate CT numbers of the pCT with the daily anatomy of the CBCT. Second, the original plans (220 cGy per fraction for 25 fractions) were copied on the rCT for dose re-calculation. Third, the DIR software Elastix was used to find the inverse transform from the rCT to the pCT. This transformation was then applied to the rCT dose grid to map the dose voxels back to their pCT location. Finally, the sum of these deformed dose grids for each patient was applied on the pCT to calculate the actual dose delivered to organs. Results: The discrepancy between the planned D98 and D2 and these indices re-calculated on the rCT, are, on average, of −1 ± 1 cGy and 1 ± 2 cGy per fraction, respectively. For fractions with large anatomical motion, the D98 discrepancy on the re-calculated dose grid mapped onto the pCT can raise to −17 ± 4 cGy. The obtained cumulative dose distributions illustrate the same behavior. Conclusion: This approach allowed the evaluation of cumulative doses to organs with the help of uncontoured daily CBCT scans. With this workflow, the easy evaluation of doses delivered for EBRT treatments could ultimately lead to a better follow-up of prostate cancer patients

  15. Automatic quantitative micro-computed tomography evaluation of angiogenesis in an axially vascularized tissue-engineered bone construct.

    Science.gov (United States)

    Arkudas, Andreas; Beier, Justus Patrick; Pryymachuk, Galyna; Hoereth, Tobias; Bleiziffer, Oliver; Polykandriotis, Elias; Hess, Andreas; Gulle, Heinz; Horch, Raymund E; Kneser, Ulrich

    2010-12-01

    We invented an automatic observer-independent quantitative method to analyze vascularization using micro-computed tomography (CT) along with three-dimensional (3D) reconstruction in a tissue engineering model. An arteriovenous loop was created in the medial thigh of 30 rats and was placed in a particulated porous hydroxyapatite and beta-tricalcium phosphate matrix, filled with fibrin (10 mg/mL fibrinogen and 2 IU/mL thrombin) without (group A) or with (group B) application of fibrin-gel-immobilized angiogenetic growth factors vascular endothelial growth factor (VEGF¹⁶⁵) and basic fibroblast growth factor (bFGF). The explantation intervals were 2, 4, and 8 weeks. Specimens were investigated by means of micro-CT followed by an automatic 3D analysis, which was correlated to histomorphometrical findings. In both groups, the arteriovenous loop led to generation of dense vascularized connective tissue with differentiated and functional vessels inside the matrix. Quantitative analysis of vascularization using micro-CT showed to be superior to histological analysis. The micro-CT analysis also allows the assessment of different other, more complex vascularization parameters within 3D constructs, demonstrating an early improvement of vascularization by application of fibrin-gel-immobilized VEGF¹⁶⁵ and bFGF. In this study quantitative analysis of vascularization using micro-CT along with 3D reconstruction and automatic analysis exhibit to be a powerful method superior to histological evaluation of cross sections.

  16. Radiation dose reduction in soft tissue neck CT using adaptive statistical iterative reconstruction (ASIR).

    Science.gov (United States)

    Vachha, Behroze; Brodoefel, Harald; Wilcox, Carol; Hackney, David B; Moonis, Gul

    2013-12-01

    To compare objective and subjective image quality in neck CT images acquired at different tube current-time products (275 mAs and 340 mAs) and reconstructed with filtered-back-projection (FBP) and adaptive statistical iterative reconstruction (ASIR). HIPAA-compliant study with IRB approval and waiver of informed consent. 66 consecutive patients were randomly assigned to undergo contrast-enhanced neck CT at a standard tube-current-time-product (340 mAs; n = 33) or reduced tube-current-time-product (275 mAs, n = 33). Data sets were reconstructed with FBP and 2 levels (30%, 40%) of ASIR-FBP blending at 340 mAs and 275 mAs. Two neuroradiologists assessed subjective image quality in a blinded and randomized manner. Volume CT dose index (CTDIvol), dose-length-product (DLP), effective dose, and objective image noise were recorded. Signal-to-noise ratio (SNR) was computed as mean attenuation in a region of interest in the sternocleidomastoid muscle divided by image noise. Compared with FBP, ASIR resulted in a reduction of image noise at both 340 mAs and 275 mAs. Reduction of tube current from 340 mAs to 275 mAs resulted in an increase in mean objective image noise (p=0.02) and a decrease in SNR (p = 0.03) when images were reconstructed with FBP. However, when the 275 mAs images were reconstructed using ASIR, the mean objective image noise and SNR were similar to those of the standard 340 mAs CT images reconstructed with FBP (p>0.05). Subjective image noise was ranked by both raters as either average or less-than-average irrespective of the tube current and iterative reconstruction technique. Adapting ASIR into neck CT protocols reduced effective dose by 17% without compromising image quality. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. PET-CT in Staging, Response Evaluation, and Surveillance of Lymphoma.

    Science.gov (United States)

    Thanarajasingam, Gita; Bennani-Baiti, Nabila; Thompson, Carrie A

    2016-05-01

    Lymphoma represents a broad spectrum of diseases with diverse biology, clinical behavior, and imaging features. Functional imaging with 18-F-fluorodeoxyglucose (FDG)-positron emission tomography combined with computed tomography (PET-CT) is widely recognized as the most sensitive and specific imaging modality for patients with lymphoma and is used as part of staging, response evaluation, and surveillance in patients with Hodgkin (HL) and non-Hodgkin lymphoma (NHL). Recent efforts at standardizing the conduct and consensus interpretation of PET-CT have facilitated its use in patients on clinical studies and beyond. The role of PET-CT has been affirmed in some clinical situations, such as staging and end-of-treatment evaluation in Hodgkin lymphoma and diffuse large B cell lymphoma (DLBCL), and in the evaluation of aggressive transformation of an indolent lymphoma. However, the role of functional imaging in other histologies and clinical settings is not as clear given the higher rate of false positive results and the costs inherent to PET-CT. There is little evidence to suggest its utility or impact on outcome in most indolent lymphomas, or in the setting of post-treatment surveillance. In addition, there remains controversy about the value of PET-CT in early response assessment during active therapy, particularly in DLBCL. This review will evaluate the evidence surrounding the role of PET-CT in staging, response evaluation and surveillance of Hodgkin and non-Hodgkin lymphoma.

  18. Nonunion of acetabular fractures: evaluation with interactive multiplanar CT

    International Nuclear Information System (INIS)

    Kuhlman, J.E.; Fishman, E.K.; Ney, D.R.; Brooker, A.F. Jr.; Magid, D.

    1989-01-01

    Nonunions involving fractures of the acetabulum are reportedly rare, with few citings and little discussion in the literature. It is possible that acetabular nonunions go undetected because imaging of the acetabulum is difficult by conventional radiography. We report two cases of fracture nonunion involving the weight-bearing surface of the acetabulum diagnosed with the aid of computed tomography (CT) and a newly developed interactive 2D/3D orthotool that uniquely processes and reformats routine CT data. The interactive 2D/3D orthotool is a sophisticated computer program that allows dynamic viewing of standard multiplanar reconstructions in the axial, coronal, and sagittal planes as well as multiple oblique projections. The 2D/3D orthotool provides on screen correlation of two-dimensional multiplanar images with three-dimensional reconstructions of the pelvis. The authors found this capability ideally suited for studying fractures with off-axis orientation such as those through the acetabular dome, greatly facilitating the diagnosis of nonunion

  19. Initial implementation of the conversion from the energy-subtracted CT number to electron density in tissue inhomogeneity corrections: An anthropomorphic phantom study of radiotherapy treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Tsukihara, Masayoshi [Division of Radiological Technology, Graduate School of Health Sciences, Niigata University, Niigata 951-8518 (Japan); Noto, Yoshiyuki [Department of Radiology, Niigata University Medical and Dental Hospital, Niigata 951-8520 (Japan); Sasamoto, Ryuta; Hayakawa, Takahide; Saito, Masatoshi, E-mail: masaito@clg.niigata-u.ac.jp [Department of Radiological Technology, School of Health Sciences, Faculty of Medicine, Niigata University, Niigata 951-8518 (Japan)

    2015-03-15

    Purpose: To achieve accurate tissue inhomogeneity corrections in radiotherapy treatment planning, the authors had previously proposed a novel conversion of the energy-subtracted computed tomography (CT) number to an electron density (ΔHU–ρ{sub e} conversion), which provides a single linear relationship between ΔHU and ρ{sub e} over a wide range of ρ{sub e}. The purpose of this study is to present an initial implementation of the ΔHU–ρ{sub e} conversion method for a treatment planning system (TPS). In this paper, two example radiotherapy plans are used to evaluate the reliability of dose calculations in the ΔHU–ρ{sub e} conversion method. Methods: CT images were acquired using a clinical dual-source CT (DSCT) scanner operated in the dual-energy mode with two tube potential pairs and an additional tin (Sn) filter for the high-kV tube (80–140 kV/Sn and 100–140 kV/Sn). Single-energy CT using the same DSCT scanner was also performed at 120 kV to compare the ΔHU–ρ{sub e} conversion method with a conventional conversion from a CT number to ρ{sub e} (Hounsfield units, HU–ρ{sub e} conversion). Lookup tables for ρ{sub e} calibration were obtained from the CT image acquisitions for tissue substitutes in an electron density phantom (EDP). To investigate the beam-hardening effect on dosimetric uncertainties, two EDPs with different sizes (a body EDP and a head EDP) were used for the ρ{sub e} calibration. Each acquired lookup table was applied to two radiotherapy plans designed using the XiO TPS with the superposition algorithm for an anthropomorphic phantom. The first radiotherapy plan was for an oral cavity tumor and the second was for a lung tumor. Results: In both treatment plans, the performance of the ΔHU–ρ{sub e} conversion was superior to that of the conventional HU–ρ{sub e} conversion in terms of the reliability of dose calculations. Especially, for the oral tumor plan, which dealt with dentition and bony structures, treatment

  20. Pathologic evaluation of normal and perfused term placental tissue

    DEFF Research Database (Denmark)

    Maroun, Lisa Leth; Mathiesen, Line; Hedegaard, Morten

    2014-01-01

    This study reports for the 1st time the incidence and interobserver variation of morphologic findings in a series of 34 term placentas from pregnancies with normal outcome used for perfusion studies. Histologic evaluation of placental tissue is challenging, especially when it comes to defining...... "normal tissue" versus "pathologic lesions." A scoring system for registration of abnormal morphologic findings was developed. Light microscopic examination was performed independently by 2 pathologists, and interobserver variation was analyzed. Findings in normal and perfused tissue were compared...... and selected findings were tested against success parameters from the perfusions. Finally, the criteria for frequent lesions with fair to poor interobserver variation in the nonperfused tissue were revised and reanalyzed. In the perfused tissue, the perfusion artefact "trophoblastic vacuolization," which...

  1. Mucosa-associated lymphoid tissue lymphoma studied with FDG-PET. A comparison with CT and endoscopic findings

    International Nuclear Information System (INIS)

    Enomoto, Keisuke; Hamada, Kenichiro; Inohara, Hidenori; Higuchi, Ichiro; Kubo, Takeshi; Hatazawa, Jun; Tomita, Yasuhiko

    2008-01-01

    We investigated the accumulation of 2-deoxy-2-[ 18 F] fluoro-D-glucose positron emission tomography (FDG-PET) in patients with mucosa-associated lymphoid tissue (MALT) lymphoma patients as compared with computerized tomography (CT) and endoscopic imaging. FDG-PET was performed on 13 untreated patients with MALT lymphoma. CT scanning of the affected areas was performed in all the patients to compare with the FDG-PET images. In five patients with gastric MALT lymphoma, comparison was also made with the endoscopic findings. Of the 13 untreated MALT lymphoma patients, all 8 non-gastric MALT lymphoma patients exhibited abnormal accumulation of FDG. However, in the five gastric MALT lymphoma patients, no abnormal FDG accumulation was observed. Although lesions could be confirmed on CT images from the patients other than those with gastric MALT lymphoma, the mucosal lesions of gastric MALT lymphoma could be observed only by endoscopy. FDG-PET can be used to detect MALT lymphoma when it forms mass lesions, whereas it is difficult to detect non-massive MALT lymphoma of gastrointestinal origin. (author)

  2. Development and characterization of a synthetic PVC/DEHP myocardial tissue analogue material for CT imaging applications.

    Science.gov (United States)

    Ramadan, Sherif; Paul, Narinder; Naguib, Hani E

    2018-04-01

    A simple myocardial analogue material has great potential to help researchers in the creation of medical CT Imaging phantoms. This work aims to outline a Bis(2-ethylhexyl) phthalate (DEHP) plasticizer/PVC material to achieve this. DEHP-PVC was manufactured in three ratios, 75, 80, and 85% DEHP by heating at 110 °C for 10 min to promote DEHP-PVC binding followed by heating at 150 °C to melt the blend. The material was then tested utilizing FTIR, tensile testing, dynamic mechanical analysis and imaged with computed tomography. The FTIR testing finds the presence of C-CL and carbonyl bonds that demonstrate the binding required in this plasticized material. The tensile testing finds a modulus of 180-20 kPa that increases with the proportion of plasticizer. The dynamic mechanical analysis finds a linear increase in viscoelastic properties with a storage/loss modulus of 6/.5-120/18 kPa. Finally, the CT number of the material increases with higher PVC content from 55 to 144HU. The 80% DEHP-PVC ratio meets the mechanical and CT properties necessary to function as a myocardial tissue analogue.

  3. CT-based manual segmentation and evaluation of paranasal sinuses.

    Science.gov (United States)

    Pirner, S; Tingelhoff, K; Wagner, I; Westphal, R; Rilk, M; Wahl, F M; Bootz, F; Eichhorn, Klaus W G

    2009-04-01

    Manual segmentation of computed tomography (CT) datasets was performed for robot-assisted endoscope movement during functional endoscopic sinus surgery (FESS). Segmented 3D models are needed for the robots' workspace definition. A total of 50 preselected CT datasets were each segmented in 150-200 coronal slices with 24 landmarks being set. Three different colors for segmentation represent diverse risk areas. Extension and volumetric measurements were performed. Three-dimensional reconstruction was generated after segmentation. Manual segmentation took 8-10 h for each CT dataset. The mean volumes were: right maxillary sinus 17.4 cm(3), left side 17.9 cm(3), right frontal sinus 4.2 cm(3), left side 4.0 cm(3), total frontal sinuses 7.9 cm(3), sphenoid sinus right side 5.3 cm(3), left side 5.5 cm(3), total sphenoid sinus volume 11.2 cm(3). Our manually segmented 3D-models present the patient's individual anatomy with a special focus on structures in danger according to the diverse colored risk areas. For safe robot assistance, the high-accuracy models represent an average of the population for anatomical variations, extension and volumetric measurements. They can be used as a database for automatic model-based segmentation. None of the segmentation methods so far described provide risk segmentation. The robot's maximum distance to the segmented border can be adjusted according to the differently colored areas.

  4. CT vs 68Ge attenuation correction in a combined PET/CT system: evaluation of the effect of lowering the CT tube current

    International Nuclear Information System (INIS)

    Kamel, Ehab; Hany, Thomas F.; Burger, Cyrill; Treyer, Valerie; Schulthess von, Gustav K.; Buck, Alfred; Lonn, Albert H.R.

    2002-01-01

    With the introduction of combined positron emission tomography/computed tomography (PET/CT) systems, several questions have to be answered. In this work we addressed two of these questions: (a) to what value can the CT tube current be reduced while still yielding adequate maps for the attenuation correction of PET emission scans and (b) how do quantified uptake values in tumours derived from CT and germanium-68 attenuation correction compare. In 26 tumour patients, multidetector CT scans were acquired with 10, 40, 80 and 120 mA (CT 10 , CT 40 , CT 80 and CT 120 ) and used for the attenuation correction of a single FDG PET emission scan, yielding four PET scans designated PET CT10 -PET CT120 . In 60 tumorous lesions, FDG uptake and lesion size were quantified on PET CT10 -PET CT120 . In another group of 18 patients, one CT scan acquired with 80 mA and a standard transmission scan acquired using 68 Ge sources were employed for the attenuation correction of the FDG emission scan (PET CT80 , PET 68Ge ). Uptake values and lesion size in 26 lesions were compared on PET CT80 and PET 68Ge . In the first group of patients, analysis of variance revealed no significant effect of CT current on tumour FDG uptake or lesion size. In the second group, tumour FDG uptake was slightly higher using CT compared with 68 Ge attenuation correction, especially in lesions with high FDG uptake. Lesion size was similar on PET CT80 and PET 68Ge . In conclusion, low CT currents yield adequate maps for the attenuation correction of PET emission scans. Although the discrepancy between CT- and 68 Ge-derived uptake values is probably not relevant in most cases, it should be kept in mind if standardised uptake values derived from CT and 68 Ge attenuation correction are compared. (orig.)

  5. Follow-up CT Evaluation of the Mural Changes in Active Takayasu Arteritis

    International Nuclear Information System (INIS)

    Kim, Sang Young; Park, Jae Hyung; Chung, Jin Wook; Kim, Hyo Cheol; Lee, Whal; So, Young Ho; Jae, Hwan Jun

    2007-01-01

    We wanted to evaluate the mural changes by CT on the follow-up examination of patients with active Takayasu arteritis. The study included 18 patients, (4 males and 14 females), with active Takayasu arteritis. A total of 44 CT examinations were done during the follow-up period (mean: 55.6 months). At the time of the last follow-up CT, the disease, on the basis of the erythrocyte sedimentation rate (ESR), was found to be inactive in five patients and the disease was active and persistent in 13 patients. The thickness and CT attenuation of the aortic wall on the precontrast, arterial and venous phases were measured on the initial and the follow-up CT examinations. The ratio of the mural attenuation over that of the back muscle on the initial CT was compared with the ratio found on the follow-up CT. The initial CT findings included high density and calcifications of the aortic wall in the precontrast images and a thickened wall with enhancements in the arterial and the venous phases. A low-attenuation ring was demonstrated in the venous phase in 15 patients (83%). On the follow-up evaluation, the mean mural thickness decreased significantly from 4.1 mm to 2.4 mm. The mean mural attenuation ratio in the venous phase decreased significantly from 1.9 to 1.3 (p 0.001). The low attenuation ring was identified in seven patients (39%) who had only with active, persistent Takayasu arteritis. The mural changes demonstrated by the follow-up CT evaluations for the patients with active Takayasu arteritis included a decrease of the mural thickness and enhancement, disappearance of the low-attenuation ring on the venous phase, and an increase of the mural attenuation and calcification on the precontrast phase

  6. Is PET/CT efficient tool to evaluate the response after stereotactic radiation therapy for pancreas cancer?

    International Nuclear Information System (INIS)

    Kim, Mi Sook; Yoo, Seong Yul; Cho, Chul Koo

    2005-01-01

    In pancreas cancer, to evaluate the efficacy of PET/CT as tool to check the response after stereotactic radiation therapy and to define functional imaging role of PET/CT as alterative tool of computed tomography. From November 2003 to December 2004, among locally advanced pancreas cancer patients treated by stereotactic radiation therapy using CyberKnife(CK), 14 were evaluated by PET/CT before and after treatment. Four patients took PET/CT one month after CK, 4 patients 2 months after CK, and 6 patients 3 months after CK as the first evaluation of treatment. All of patients were also evaluated by CT or CA19-9 tumor antigen with the range of 1-2 months after CK. In addition of PET/CT to CT, lymph node metastasis were revealed as positive in 4 patients who had negative finding on CT. Furthermore, patients who showed partial or complete response on PET/CT findings that checked within 3 months after CK have significantly longer median survival time than patients who showed no response or disease progression(13 months and 9 months, respectively). Responses based on CA19-9 tumor antigen or CT, however, showed no significant difference in terms of median survival time. PET/CT can provide more information for lymph node metastasis compared to CT alone. It is very helpful for delineation of tumor extent for CK planning. And initial response on PET/CT scan could be a significant prognostic factor rather than response on CA19-9 level or CT. In the future, more study is necessary to evaluate if PET/CT could substitute CT and finally CT could be omitted during follow-up period after CK

  7. Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

    Energy Technology Data Exchange (ETDEWEB)

    Tutcu, Semra [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Serter, Selim, E-mail: serterselim@gmail.co [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Kaya, Yavuz; Kara, Eray [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Nese, Nalan [Department of Pathology, Celal Bayar University, School of Medicine, Manisa (Turkey); Pekindil, Goekhan [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Coskun, Teoman [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey)

    2010-08-15

    Purpose: It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT. Materials and methods: Forty Sprague-Dawley rats of both genders with average weights of 250 g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses. Results: In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p < 0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance. Conclusion: The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.

  8. Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

    International Nuclear Information System (INIS)

    Tutcu, Semra; Serter, Selim; Kaya, Yavuz; Kara, Eray; Nese, Nalan; Pekindil, Goekhan; Coskun, Teoman

    2010-01-01

    Purpose: It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT. Materials and methods: Forty Sprague-Dawley rats of both genders with average weights of 250 g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses. Results: In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p < 0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance. Conclusion: The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.

  9. CT diagnosis of hepatic alveolar echinococcosis and evaluation after albendazole chemotherapy

    International Nuclear Information System (INIS)

    Wu Jingquan; Liu Yuehan; Wang Xiaogen

    1998-01-01

    Purpose: To analyze the CT features and evaluate albendazole chemotherapy of hepatic alveolar echinococcosis with computed tomography (CT). Methods: Twenty-one patients of hepatic alveolar echincoccosis were diagnosed by epidemiological, clinical, serological tests, and studied with US and CT. Twenty patients were followed up by CT scanning from 1 to 9 years (mean 3.9 years) after albendazole chemotherapy. Results: CT scanning of liver before treatment displayed heterogeneous hypodense lesions, with irregular, obscure contour and calcifications According to CT features, the hepatic lesions were divided into 3 forms: solid mass in 7 cases, pseudocyst in 6 cases and mixed in 8 cases. Three patients had contrast study. The hepatic lesions were not markedly enhanced, but the lesions were seen more clearly and appeared more extensive. In follow-up examination of 20 cases, 4 were apparently cured, 5 improved, 5 stabilized, and 6 cases remained pseudocyst. Conclusion: CT scanning was of value not only for diagnosis of hepatic alveolar echinococcosis, but also useful in evaluation of chemotherapeutic efficacy

  10. Comparison of personal computer with CT workstation in the evaluation of 3-dimensional CT image of the skull

    International Nuclear Information System (INIS)

    Kang, Bok Hee; Kim, Kee Deog; Park, Chang Seo

    2001-01-01

    To evaluate the usefulness of the reconstructed 3-dimensional image on the personal computer in comparison with that of the CT workstation by quantitative comparison and analysis. The spiral CT data obtained from 27 persons were transferred from the CT workstation to a personal computer, and they were reconstructed as 3-dimensional image on the personal computer using V-works 2.0 TM . One observer obtained the 14 measurements on the reconstructed 3-dimensional image on both the CT workstation and the personal computer. Paired test was used to evaluate the intraobserver difference and the mean value of the each measurement on the CT workstation and the personal computer. Pearson correlation analysis and % imcongruence were also performed. I-Gn, N-Gn, N-A, N-Ns, B-A and G-Op did not show any statistically significant difference (p>0.05), B-O, B-N, Eu-Eu, Zy-Zy, Biw, D-D, Orbrd R, and L had statistically significant difference (p<0.05), but the mean values of the differences of all measurements were below 2 mm, except for D-D. The value of correlation coefficient γ was greater than 0.95 at I-Gn, N-Gn, N-A, N-Ns, B-A, B-N, G-Op, Eu-Eu, Zy-Zy, and Biw, and it was 0.75 at B-O, 0.78 at D-D, and 0.82 at both Orbrb R and L. The % incongruence was below 4% at I-Gn, N-Gn, N-A, N-Ns, B-A, B-N, G-Op, Eu-Eu, Zy-Zy, and Biw, and 7.18%, 10.78%, 4.97%, 5.89% at B-O, D-D, Orbrb R and L respectively. It can be considered that the utilization of the personal computer has great usefulness in reconstruction of the 3-dimensional image when it comes to the economics, accessibility and convenience, except for thin bones and the landmarks which and difficult to be located

  11. Characterization of brown adipose tissue 18F-FDG uptake in PET/CT imaging and its influencing factors in the Chinese population

    International Nuclear Information System (INIS)

    Shao, Xiaonan; Shao, Xiaoliang; Wang, Xiaosong; Wang, Yuetao

    2016-01-01

    18 F-FDG PET/CT has been widely applied for tumor imaging. However, it is reported that many normal tissues, e.g., brown adipose tissue, can also uptake 18 F-FDG. The purpose of this study was to determine the imaging characteristics of 18 F-FDG uptake in brown adipose tissue (BAT) in PET/CT. A total of 2,944 patients who underwent PET/CT from September 2011 to March 2013 were analyzed retrospectively. Imaging features of 18 F-FDG uptake in BAT were analyzed. Univariate analysis and logistic regression analysis were performed to evaluate the effect of age, gender, cancer status, body mass index (BMI), average daily maximum temperature of imaging month and fasting plasma glucose (Glu) on the positive rate of 18 F-FDG uptake in BAT. The results showed that 1.9% (57/2944) patients had 18 F-FDG uptake in BAT. 18 F-FDG, manifested as flaky, nodular and beaded shape, was symmetrically distributed in the adipose tissues of cervical and supraclavicular, mediastinal, paravertebral, and perirenal areas. Uptake of 18 F-FDG within cervical/supraclavicular area was most common (89.5%, 51/57) with an SUV max ranging from 2.8 to 31.4. Univariate analysis showed that gender and cancer status were not significantly correlated with the BAT 18 F-FDG uptake rate. In contrast, age, BMI, Glu and average daily maximum temperature in the imaging month were significantly correlated with the BAT 18 F-FDG uptake rate (P < 0.05). Further logistic regression analysis showed that only age, BMI and average daily maximum temperature were significant (OR < 1, P < 0.05). Based on the value of OR, the most significant factor that affects BAT 18 F-FDG uptake rate was age, followed by the average daily maximum temperature and BMI. We concluded that Chinese adult has low positive rate of 18 F-FDG uptake in BAT. Cervical/Supraclavicular is the most common area with BAT 18 F-FDG uptake. Age, average daily maximum temperature and BMI are independent factors affecting 18 F-FDG uptake.

  12. Association between CT-evaluated lumbar lordosis and features of spinal degeneration, evaluated in supine position

    Science.gov (United States)

    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

  13. CT-based patient modeling for head and neck hyperthermia treatment planning: manual versus automatic normal-tissue-segmentation.

    Science.gov (United States)

    Verhaart, René F; Fortunati, Valerio; Verduijn, Gerda M; van Walsum, Theo; Veenland, Jifke F; Paulides, Margarethus M

    2014-04-01

    Clinical trials have shown that hyperthermia, as adjuvant to radiotherapy and/or chemotherapy, improves treatment of patients with locally advanced or recurrent head and neck (H&N) carcinoma. Hyperthermia treatment planning (HTP) guided H&N hyperthermia is being investigated, which requires patient specific 3D patient models derived from Computed Tomography (CT)-images. To decide whether a recently developed automatic-segmentation algorithm can be introduced in the clinic, we compared the impact of manual- and automatic normal-tissue-segmentation variations on HTP quality. CT images of seven patients were segmented automatically and manually by four observers, to study inter-observer and intra-observer geometrical variation. To determine the impact of this variation on HTP quality, HTP was performed using the automatic and manual segmentation of each observer, for each patient. This impact was compared to other sources of patient model uncertainties, i.e. varying gridsizes and dielectric tissue properties. Despite geometrical variations, manual and automatic generated 3D patient models resulted in an equal, i.e. 1%, variation in HTP quality. This variation was minor with respect to the total of other sources of patient model uncertainties, i.e. 11.7%. Automatically generated 3D patient models can be introduced in the clinic for H&N HTP. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. CT-based patient modeling for head and neck hyperthermia treatment planning: Manual versus automatic normal-tissue-segmentation

    International Nuclear Information System (INIS)

    Verhaart, René F.; Fortunati, Valerio; Verduijn, Gerda M.; Walsum, Theo van; Veenland, Jifke F.; Paulides, Margarethus M.

    2014-01-01

    Background and purpose: Clinical trials have shown that hyperthermia, as adjuvant to radiotherapy and/or chemotherapy, improves treatment of patients with locally advanced or recurrent head and neck (H and N) carcinoma. Hyperthermia treatment planning (HTP) guided H and N hyperthermia is being investigated, which requires patient specific 3D patient models derived from Computed Tomography (CT)-images. To decide whether a recently developed automatic-segmentation algorithm can be introduced in the clinic, we compared the impact of manual- and automatic normal-tissue-segmentation variations on HTP quality. Material and methods: CT images of seven patients were segmented automatically and manually by four observers, to study inter-observer and intra-observer geometrical variation. To determine the impact of this variation on HTP quality, HTP was performed using the automatic and manual segmentation of each observer, for each patient. This impact was compared to other sources of patient model uncertainties, i.e. varying gridsizes and dielectric tissue properties. Results: Despite geometrical variations, manual and automatic generated 3D patient models resulted in an equal, i.e. 1%, variation in HTP quality. This variation was minor with respect to the total of other sources of patient model uncertainties, i.e. 11.7%. Conclusions: Automatically generated 3D patient models can be introduced in the clinic for H and N HTP

  15. Abdominal adipose tissue distribution in obese children. US versus CT measurements; Valutazione della distribuzione del tessuto adiposo addominale nei bambini obesi. Confronto tra ecografia e Tomografia Computerizzata

    Energy Technology Data Exchange (ETDEWEB)

    Ferrozzi, F.; Zuccoli, G.; Tognini, G.; Castriota-Scanderbeg, A.; Bacchini, E. [Parma Univ., Parma (Italy). Ist. di Scienze Radiologiche; Bernasconi, S. [Modena Univ., Modena (Italy). Clinica Pediatrica; Campani, R. [Pavia Univ., Pavia (Italy). Ist. di Radiologia

    1999-12-01

    Computed Tomography (CT) and, more recently, ultrasound (US), have proved excellent tools for quantifying adipose tissue distribution. Body fat distribution is an important factor in the treatment of obesity and its complications. In this work it is investigated the correlation between CT and US measurements in pediatric obesity. Forty obese children and adolescents aged 4.1-14.8 years were submitted to CT and US. Intra-abdominal, subcutaneous and total body fat were calculated (in cm{sup 2}), with the CT image analysis software. The rectus muscle-spine and rectus muscle-aorta distances, as indicative of visceral fat thickness, were measured on US images with(out) compression. The distance between skin fat and fat-rectus muscle interfaces was measured as subcutaneous fat thickness. US-CT findings have been compared with other morphometric variables-i.e., patient's (ideal) body weight and skin fold measures. A statistically significant correlation was found between the CT measurement of visceral fat and the aorta-rectus muscle and rectus muscle-spine distances (r=0.80 and 0.74, respectively). The US measurements of subcutaneous fat were correlated with CT subcutaneous fat area (r=0.82). No correlation was found between overweight, as calculated by body mass index, and CT or US fat. In conclusions, the findings indicate that US is as useful as CT in evaluating body fat distribution in pediatric obesity. [Italian] La TC e piu' recentemente l'ecografia si sono dimostrate eccellenti tecniche di valutazione della quantita' e della distribuzione del tessuto adiposo corporeo. La compartimentazione del grasso corporeo ha, infatti, importanti implicazioni per il trattamento dell'obesita' e delle sue complicanze. Scopo dello studio e' stato quello di correlare i risultati ottenuti con la TC con quelli ecografici nella valutazione dell'obesita' del paziente pediatrico. Quaranta bambini obesi con eta' compresa tra 4,1 e 14

  16. Iodine-enhanced micro-CT imaging: methodological refinements for the study of the soft-tissue anatomy of post-embryonic vertebrates.

    Science.gov (United States)

    Gignac, Paul M; Kley, Nathan J

    2014-05-01

    The now widespread use of non-destructive X-ray computed tomography (CT) and micro-CTCT) has greatly augmented our ability to comprehensively detail and quantify the internal hard-tissue anatomy of vertebrates. However, the utility of X-ray imaging for gaining similar insights into vertebrate soft-tissue anatomy has yet to be fully realized due to the naturally low X-ray absorption of non-mineralized tissues. In this study, we show how a wide diversity of soft-tissue structures within the vertebrate head-including muscles, glands, fat deposits, perichondria, dural venous sinuses, white and gray matter of the brain, as well as cranial nerves and associated ganglia-can be rapidly visualized in their natural relationships with extraordinary levels of detail using iodine-enhanced (i-e) µCT imaging. To date, Lugol's iodine solution (I2 KI) has been used as a contrast agent for µCT imaging of small invertebrates, vertebrate embryos, and certain isolated parts of larger, post-embryonic vertebrates. These previous studies have all yielded promising results, but visualization of soft tissues in smaller invertebrate and embryonic vertebrate specimens has generally been more complete than that for larger, post-embryonic vertebrates. Our research builds on these previous studies by using high-energy µCT together with more highly concentrated I2 KI solutions and longer staining times to optimize the imaging and differentiation of soft tissues within the heads of post-embryonic archosaurs (Alligator mississippiensis and Dromaius novaehollandiae). We systematically quantify the intensities of tissue staining, demonstrate the range of anatomical structures that can be visualized, and generate a partial three-dimensional reconstruction of alligator cephalic soft-tissue anatomy. © 2014 Wiley Periodicals, Inc.

  17. Evaluation of pulmonary emphysema by the fused image of CT image and ventilation SPECT image

    International Nuclear Information System (INIS)

    Okuda, Ituko; Maruno, Hiromasa; Mori, Kazuaki; Kohno, Tadashi; Kokubo, Takashi

    2007-01-01

    We evaluated pulmonary emphysema using a diagnostic device that could obtain a CT image, a ventilation single photon emission computed tomography (SPECT) image and a lung perfusion SPECT image in one examination. The fused image made from the CT image and SPECT image had very little position gap between images, and the precision was high. From the fused image, we were able to detect the areas in which emphysematous change was the most marked in the CT image, while the accumulation decrease was most remarkable in the ventilation SPECT image. Thus it was possible to obtain an accurate status of pulmonary emphysema, and our method was regarded as a useful technique. (author)

  18. Comparison of MR imaging and CT in the evaluation of uterine tumors

    International Nuclear Information System (INIS)

    Janus, C.L.; Dottino, P.; Brodman, M.; Goodman, H.; Gendal, E.S.; Rabinowitz, J.G.

    1987-01-01

    The authors compared the usefulness of MR imaging and CT in staging uterine tumors. Forty women with known cervical carcinoma, endometrial cancer, or leiomyosarcoma underwent CT and MR imaging within 1 week prior to surgery. MR imaging was better than CT for localizing tumors to the endometrium of myometrium and in the evaluation of lymph node involvement and extension to the cervix and parametria. MR imaging, with its superior ability to demonstrate pelvic anatomy and its lack of ionizing radiation and risk from iodinated contrast media, has an important place in the staging of uterine tumors

  19. Evaluation of the low dose cardiac CT imaging using ASIR technique

    Science.gov (United States)

    Fan, Jiahua; Hsieh, Jiang; Deubig, Amy; Sainath, Paavana; Crandall, Peter

    2010-04-01

    Today Cardiac imaging is one of the key driving forces for the research and development activities of Computed Tomography (CT) imaging. It requires high spatial and temporal resolution and is often associated with high radiation dose. The newly introduced ASIR technique presents an efficient method that offers the dose reduction benefits while maintaining image quality and providing fast reconstruction speed. This paper discusses the study of image quality of the ASIR technique for Cardiac CT imaging. Phantoms as well as clinical data have been evaluated to demonstrate the effectiveness of ASIR technique for Cardiac CT applications.

  20. MRI, CT, and sonography in the preoperative evaluation of primary tumor extension in malignant pleural mesothelioma

    International Nuclear Information System (INIS)

    Layer, G.; Steudel, A.; Schild, H.H.; Schmitteckert, H.; Tuengerthal, S.; Schirren, J.; Kaick, G. van

    1999-01-01

    Purpose: Evaluation of the diagnostic value of the imaging modalities computed tomography (CT), magnetic resonance imaging (MRI), and thoracic sonography in the preoperative staging of malignant pleural mesothelioma. Results: The accuracy rates for CT were 85%, 98%, 83%, 73%, 71%, and 83%. MRI had an accuracy of 71%, 92%, 71%, 83%, 71%, and 96%, the thoracic ultrasound examinations of 76%, 63%, 51%, 60%, 71% and 89%. Conclusions: According to these results CT remains the method of choice in the preoperative assessment of T-stage of malignant pleural mesothelioma. MRI is of nearly the same value, but is not a must. Sonography may be supplementary method for operation planning. (orig./AJ) [de

  1. CT evaluation of underlying cause in spontaneous subcapsular and perirenal hemorrhage

    International Nuclear Information System (INIS)

    Sebastia, M.C.; Perez-Molina, M.O.; Alvarez-Castells, A.; Quiroga, S.; Pallisa, E.

    1997-01-01

    We evaluated the CT scans of 13 patients with spontaneous subcapsular or perinephric hemorrhage (SPH) associated with these underlying causes: 4 angiomyolipomas, 2 renal cell carcinomas, 1 renal metastatic malignant melanoma, 1 ruptured renal artery aneurysm, 1 adrenal myelolipoma, 1 ruptured renal abscess, 2 ruptured hemorrhagic cysts, and 1 patient with undiagnosed coagulation disorder. Our objective was to ascertain whether an underlying cause of SPH was identifiable by CT, and to determine the extension of the hematomas. Computed tomography identified the hematoma in all 13 cases (sensitivity 100 %). In all 12 cases in which there was a renal or adrenal anatomic lesion, the underlying cause was identified with CT (100 %), with correct diagnosis in 11 cases (91.6 %). The case in which no lesion was identified was the undiagnosed coagulation disorder. We conclude that CT is a useful technique for the initial evaluation of SPH, permitting diagnosis of hemorrhage and identification of the underlying cause. (orig.). With 6 figs., 1 tab

  2. CT evaluation of underlying cause in spontaneous subcapsular and perirenal hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Sebastia, M.C. [Department of Radiology, IDI, Hospital General Universitari Vall d`Hebron, E-08 305 Barcelona (Spain); Perez-Molina, M.O. [Department of Radiology, IDI, Hospital General Universitari Vall d`Hebron, E-08 305 Barcelona (Spain); Alvarez-Castells, A. [Department of Radiology, IDI, Hospital General Universitari Vall d`Hebron, E-08 305 Barcelona (Spain); Quiroga, S. [Department of Radiology, IDI, Hospital General Universitari Vall d`Hebron, E-08 305 Barcelona (Spain); Pallisa, E. [Department of Radiology, IDI, Hospital General Universitari Vall d`Hebron, E-08 305 Barcelona (Spain)

    1997-06-01

    We evaluated the CT scans of 13 patients with spontaneous subcapsular or perinephric hemorrhage (SPH) associated with these underlying causes: 4 angiomyolipomas, 2 renal cell carcinomas, 1 renal metastatic malignant melanoma, 1 ruptured renal artery aneurysm, 1 adrenal myelolipoma, 1 ruptured renal abscess, 2 ruptured hemorrhagic cysts, and 1 patient with undiagnosed coagulation disorder. Our objective was to ascertain whether an underlying cause of SPH was identifiable by CT, and to determine the extension of the hematomas. Computed tomography identified the hematoma in all 13 cases (sensitivity 100 %). In all 12 cases in which there was a renal or adrenal anatomic lesion, the underlying cause was identified with CT (100 %), with correct diagnosis in 11 cases (91.6 %). The case in which no lesion was identified was the undiagnosed coagulation disorder. We conclude that CT is a useful technique for the initial evaluation of SPH, permitting diagnosis of hemorrhage and identification of the underlying cause. (orig.). With 6 figs., 1 tab.

  3. The evaluation of gallbladder contractibility for volume measurement by helical 3D-CT-cholangiography

    International Nuclear Information System (INIS)

    Hanaguri, Katsuro; Kimura, Hideaki; Kayashima, Yasuyo; Suemoto, Kouichiro; Makihata, Hiroshi; Maruhashi, Akira; Ohya, Toshihide; Ito, Katsuhide; Shen, Yun.

    1997-01-01

    As a new application of helical (spiral) scan, volume measurement has received a significant interest. Although it is important to evaluate gallbladder contractibility to decide on a treatment plan for a gallbladder lesion, qualitative analysis of gallbladder contractibility is very difficult owing to the fact that the volume of gallbladder can not be measured using usual DIC examination (plain X-P and tomography). In this study, the accuracy of volume measurement of helical CT was checked firstly by gallbladder phantom experiments. Then 128 cases of volume measurement of helical 3D CT Cholangiography (DIC-CT) were performed. Under the conditions of optimized scan technique (3 mm TH, 3 mm/s, 1 mm recon interval, Hispeed, GEMS), the difference of contractibility was obtained between clinical cases with and without thick wall. The experiment has shown that helical 3D CT volume measurement is very simple and highly accurate method which is useful for the evaluation of gallbladder contractibility. (author)

  4. 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.

  5. Evaluation of mechanical precision and alignment uncertainties for an integrated CT/LINAC system

    International Nuclear Information System (INIS)

    Court, Laurence; Rosen, Isaac; Mohan, Radhe; Dong Lei

    2003-01-01

    A new integrated CT/LINAC combination, in which the CT scanner is inside the radiation therapy treatment room and the same patient couch is used for CT scanning and treatment (after a 180-degree couch rotation), should allow for accurate correction of interfractional setup errors. The purpose of this study was to evaluate the sources of uncertainties, and to measure the overall precision of this system. The following sources of uncertainty were identified: (1) the patient couch position on the LINAC side after a rotation, (2) the patient couch position on the CT side after a rotation, (3) the patient couch position as indicated by its digital readout, (4) the difference in couch sag between the CT and LINAC positions, (5) the precision of the CT coordinates, (6) the identification of fiducial markers from CT images, (7) the alignment of contours with structures in the CT images, and (8) the alignment with setup lasers. The largest single uncertainties (one standard deviation or 1 SD) were found in couch position on the CT side after a rotation (0.5 mm in the RL direction) and the alignment of contours with the CT images (0.4 mm in the SI direction). All other sources of uncertainty are less than 0.3 mm (1 SD). The overall precision of two setup protocols was investigated in a controlled phantom study. A protocol that relies heavily on the mechanical integrity of the system, and assumes a fixed relationship between the LINAC isocenter and the CT images, gave a predicted precision (1 SD) of 0.6, 0.7, and 0.6 mm in the SI, RL and AP directions, respectively. The second protocol reduces reliance on the mechanical precision of the total system, particularly the patient couch, by using radio-opaque fiducial markers to transfer the isocenter information from the LINAC side to the CT images. This protocol gave a slightly improved predicted precision of 0.5, 0.4, and 0.4 mm in the SI, RL and AP directions, respectively. The distribution of phantom position after CT

  6. Visualization of superparamagnetic nanoparticles in vascular tissue using XμCT and histology.

    Science.gov (United States)

    Tietze, Rainer; Rahn, Helene; Lyer, Stefan; Schreiber, Eveline; Mann, Jenny; Odenbach, Stefan; Alexiou, Christoph

    2011-02-01

    In order to increase the dose of antineoplastic agents in the tumor area, the concept of magnetic drug targeting (MDT) has been developed. Magnetic nanoparticles consisting of iron oxide and a biocompatible cover layer suspended in an aqueous solution (ferrofluid) serve as carriers for chemotherapeutics being enriched by an external magnetic field after intra-arterial application in desired body compartments (i.e., tumor). We established an ex vivo model to simulate in vivo conditions in a circulating system consisting of magnetic iron oxide nanoparticles passing an intact bovine artery and being focused by an external magnetic field to study their distribution in the vessel. Micro-computed X-ray tomography (XμCT) and histology can elucidate the arrangement of these particles after application. XμCT-analysis has been performed on arterial sections after MDT in order to determine the distribution of the nanoparticles. These measurements have been carried out with a cone X-ray source and corresponding histological sections were stained with Prussian blue. It could be shown that combining XμCT and histology offers the opportunity for a better understanding of the mechanisms of nanoparticle deposition in the vascular system after MDT.

  7. MicroCT Scan in paleobiology: application to the study of dental tissues

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, M.; Casali, F. E-mail: casali@bo.infn.it; Romani, D.; Bondioli, L.; Macchiarelli, R.; Rook, L

    2004-01-01

    State of the art in paleoanthropological and paleoprimatological research foresees the use of advanced non-destructive investigative approaches. Microcomputed tomography (microCT) is a fundamental tool, since it offers the opportunity to get high quality morphological information with high spatial resolution. We carried out the set-up of an experimental microCT system able to examine paleobiological samples. The equipment can operate on small objects (size up to 3 cm) with a nominal spatial resolution of 30 {mu}m, allowing their 3D volume reconstruction and morphometric analysis. This approach represents a forefront technique in paleobiological studies, successfully employed only in a limited number of advanced research centers. A specific program of microCT analysis has been planned on a sample of human and non-human fossil primate dentitions, in order to assess the specific nature of a number of tooth lesions (e.g. caries versus abrasion). This currently in progress experimental activity represents the first step for the set-up of a research center specifically devoted to the realization of advanced studies in the field of archaeo-paleobiology.

  8. How to use PET/CT in the evaluation of response to radiotherapy.

    Science.gov (United States)

    Decazes, Pierre; Thureau, Sébastien; Dubray, Bernard; Vera, Pierre

    2017-11-28

    Radiotherapy is a major treatment modality for many cancers. Tumor response after radiotherapy determines the subsequent steps of the patient's management (surveillance, adjuvant or salvage treatment and palliative care). Tumor response assessed during radiotherapy offers a promising opportunity to adapt the treatment plan to reduced / increased target volume, to specifically target sub-volumes with relevant biological characteristics (metabolism, hypoxia, proliferation ...) and to further spare the organs at risk. In addition to its role in the diagnosis and the initial staging, Positron Emission Tomography combined with a Computed Tomography (PET/CT) provides functional information and is therefore attractive to evaluate tumor response. To review the published data addressing PET/CT as an evaluation tool in irradiated tumors. Reports on PET/CT acquired at various times (during radiotherapy, after initial (chemo-)radiotherapy, after definitive radiotherapy and during posttreatment follow-up) in solid tumors (lung, head-and-neck, cervix, esophagus, prostate and rectum) were collected and reviewed. Various tracers and technical are also discussed. 18F-FDG PET/CT has a well-established role in clinical routine after definitive chemo-radiotherapy for locally advanced head-and-neck cancers. 18F-choline PET/CT is indicated in prostate cancer patients with biochemical failure. 18F-FDG PET/CT is optional in many others circumstances and the clinical benefits of assessing tumor response with PET/CT remain a field of very active research. The combination of PET with Magnetic Resonance Imaging (PET/MRI) may prove to be valuable in irradiated rectal and cervix cancers. Tumor response can be evaluated by PET/CT with clinical consequences in multiple situations, notably in head and neck and prostate cancers, after radiotherapy. Further clinical evaluation for most cancers is still needed, possibly in association to MRI.

  9. Evaluation of PET Scanner Performance in PET/MR and PET/CT Systems: NEMA Tests

    OpenAIRE

    Mustafa Demir; Türkay Toklu; Mohammad Abuqbeitah; Hüseyin Çetin; H. Sezer Sezgin; Nami Yeyin; Kerim Sönmezoğlu

    2018-01-01

    Objective: The aim of the present study was to compare the performance of positron emission tomography (PET) component of PET/computed tomography (CT) with new emerging PET/magnetic resonance (MR) of the same vendor. Methods: According to National Electrical Manufacturers Association NU2-07, five separate experimental tests were performed to evaluate the performance of PET scanner of General Electric GE company; SIGNATM model PET/MR and GE Discovery 710 model PET/CT. The main investigated...

  10. Evaluation of PET Scanner Performance in PET/MR and PET/CT Systems: NEMA Tests

    OpenAIRE

    Demir, Mustafa; Toklu, Türkay; Abuqbeitah, Mohammad; Çetin, Hüseyin; Sezgin, H. Sezer; Yeyin, Nami; Sönmezoğlu, Kerim

    2018-01-01

    Objective: The aim of the present study was to compare the performance of positron emission tomography (PET) component of PET/computed tomography (CT) with new emerging PET/magnetic resonance (MR) of the same vendor. Methods: According to National Electrical Manufacturers Association NU2-07, five separate experimental tests were performed to evaluate the performance of PET scanner of General Electric GE company; SIGNATM model PET/MR and GE Discovery 710 model PET/CT. The main investigated asp...

  11. Clinical utility of F-18 FDG PET-CT in the initial evaluation of lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, Poul Henning [Vejle Hospital, Department of Medicine, Division of Respiratory Medicine, Vejle (Denmark); Holdgaard, Paw Christian [Vejle Hospital, Department of Nuclear Medicine, Vejle (Denmark); Christensen, Janne Buck [Odense University Hospital/University of Southern Denmark, Department of Quality and Research/HTA, Odense University Hospital and Medical Research Library, Odense (Denmark); Hoeilund-Carlsen, Poul Flemming [Odense University Hospital, Department of Nuclear Medicine, Odense (Denmark)

    2016-10-15

    Positron emission tomography-computed tomography (PET-CT) is a resource-demanding imaging modality with increasing popularity in the workup of patients with suspected or proven lung cancer. To review the clinical usefulness of this imaging modality in the diagnosis, staging, and pre-operative evaluation, we conducted a systematic literature search, review, and quality assessment using the rapid evidence assessment toolkit and the Oxford Centre for Evidence-Based Medicine methodology. The literature search resulted in 4,208 records including 918 reviews, of which 139 met the predefined criteria and were read in full to identify relevant original articles on F-18 FDG PET-CT (1) in the evaluation of solitary pulmonary nodules (n = 14), (2) in curative-intent treatment trials (n = 9), and (3) in planning of invasive procedures (n = 18). We found the following important results from the literature review: (1) PET-CT can rule out malignancy in most solitary pulmonary nodules due to high sensitivity (recommendation level A). (2) PET-CT reduces the number of futile treatment trials (recommendation level A). (3) The sensitivity of PET-CT in general is insufficient to rule out mediastinal lymph node metastasis (recommendation level A). (1) With few exceptions, solitary pulmonary nodules can safely be considered benign if the PET-CT scan is negative. Exceptions consist of small (<1 cm) and non-solid, solitary pulmonary nodules. These abnormalities should be followed up by CT in a structured programme. (2) No curative-intent treatment should be commenced until a PET-CT scan has excluded occult distant metastases. (3) In general, lymph node metastasis in the mediastinum cannot be ruled out on the basis of a negative PET-CT, and confirmative invasive staging should be performed in most patients before mediastinal metastasis is confirmed or ruled out. (orig.)

  12. Evaluation of patient absorbed dose in a PET-CT test

    International Nuclear Information System (INIS)

    Guerra P, F.; Mourao F, A. P.; Santana, P. C.

    2017-10-01

    Images of PET-CT has important diagnostic applications, especially in oncology. This equipment allows overlapping of functional images obtained from the administration of radionuclides and anatomical, generated by X-rays. The PET-CT technique may generate higher doses in patients due to the fact that two diagnostic modalities are used in a single examination. A whole body CT scan is performed and in sequence, a capture of the signal generated by the photons emitted is done. In this study, the absorbed and effective doses generated by the CT scan and incorporated by the administration of the radionuclide were evaluated in 19 organs. To evaluate the CT dose, 32 radiochromic film strips were correctly positioned into the anthropomorphic male phantom. The CT protocol performed was whole-body scanning and a high-resolution lung scan. This protocol is currently used in most services. The calculation of the effective dose from the injected activity in the patient was performed using the ICRP 106 Biokinetic model (ICRP 106, 2008). The activity to be injected may vary according to the patients body mass and with the sensitivity of the detector. The mass of the simulator used is 73.5 kg, then the simulation with and injected activity of 244.76 MBq was used. It was observed that 87.4% of the effective dose in examination PET/CT comes from the CT scans, being 63.8% of the whole body scan and 23.6% of high resolution lung scan. Using activity of 0.09 mCi x kg 18 F-FDG radiopharmaceutical contributes only 12.6% of the final effective dose. As a conclusion, it was observed that the dose in patients submitted to the 18 F-FDG PET-CT examination is high, being of great value efforts for its reduction, such as the use of appropriate image acquisition techniques and promoting the application of the principle of optimization of practice. (Author)

  13. Clinical utility of F-18 FDG PET-CT in the initial evaluation of lung cancer

    International Nuclear Information System (INIS)

    Madsen, Poul Henning; Holdgaard, Paw Christian; Christensen, Janne Buck; Hoeilund-Carlsen, Poul Flemming

    2016-01-01

    Positron emission tomography-computed tomography (PET-CT) is a resource-demanding imaging modality with increasing popularity in the workup of patients with suspected or proven lung cancer. To review the clinical usefulness of this imaging modality in the diagnosis, staging, and pre-operative evaluation, we conducted a systematic literature search, review, and quality assessment using the rapid evidence assessment toolkit and the Oxford Centre for Evidence-Based Medicine methodology. The literature search resulted in 4,208 records including 918 reviews, of which 139 met the predefined criteria and were read in full to identify relevant original articles on F-18 FDG PET-CT (1) in the evaluation of solitary pulmonary nodules (n = 14), (2) in curative-intent treatment trials (n = 9), and (3) in planning of invasive procedures (n = 18). We found the following important results from the literature review: (1) PET-CT can rule out malignancy in most solitary pulmonary nodules due to high sensitivity (recommendation level A). (2) PET-CT reduces the number of futile treatment trials (recommendation level A). (3) The sensitivity of PET-CT in general is insufficient to rule out mediastinal lymph node metastasis (recommendation level A). (1) With few exceptions, solitary pulmonary nodules can safely be considered benign if the PET-CT scan is negative. Exceptions consist of small (<1 cm) and non-solid, solitary pulmonary nodules. These abnormalities should be followed up by CT in a structured programme. (2) No curative-intent treatment should be commenced until a PET-CT scan has excluded occult distant metastases. (3) In general, lymph node metastasis in the mediastinum cannot be ruled out on the basis of a negative PET-CT, and confirmative invasive staging should be performed in most patients before mediastinal metastasis is confirmed or ruled out. (orig.)

  14. A quality assurance phantom for the performance evaluation of volumetric micro-CT systems

    Energy Technology Data Exchange (ETDEWEB)

    Du, Louise Y [Department of Medical Biophysics, University of Western Ontario, London, ON (Canada); Umoh, Joseph [Imaging Research Laboratories, Robarts Research Institute, London, ON (Canada); Nikolov, Hristo N [Imaging Research Laboratories, Robarts Research Institute, London, ON (Canada); Pollmann, Steven I [Imaging Research Laboratories, Robarts Research Institute, London, ON (Canada); Lee, Ting-Yim [Department of Medical Biophysics, University of Western Ontario, London, ON (Canada); Holdsworth, David W [Department of Medical Biophysics, University of Western Ontario, London, ON (Canada)

    2007-12-07

    Small-animal imaging has recently become an area of increased interest because more human diseases can be modeled in transgenic and knockout rodents. As a result, micro-computed tomography (micro-CT) systems are becoming more common in research laboratories, due to their ability to achieve spatial resolution as high as 10 {mu}m, giving highly detailed anatomical information. Most recently, a volumetric cone-beam micro-CT system using a flat-panel detector (eXplore Ultra, GE Healthcare, London, ON) has been developed that combines the high resolution of micro-CT and the fast scanning speed of clinical CT, so that dynamic perfusion imaging can be performed in mice and rats, providing functional physiological information in addition to anatomical information. This and other commercially available micro-CT systems all promise to deliver precise and accurate high-resolution measurements in small animals. However, no comprehensive quality assurance phantom has been developed to evaluate the performance of these micro-CT systems on a routine basis. We have designed and fabricated a single comprehensive device for the purpose of performance evaluation of micro-CT systems. This quality assurance phantom was applied to assess multiple image-quality parameters of a current flat-panel cone-beam micro-CT system accurately and quantitatively, in terms of spatial resolution, geometric accuracy, CT number accuracy, linearity, noise and image uniformity. Our investigations show that 3D images can be obtained with a limiting spatial resolution of 2.5 mm{sup -1} and noise of {+-}35 HU, using an acquisition interval of 8 s at an entrance dose of 6.4 cGy.

  15. A quality assurance phantom for the performance evaluation of volumetric micro-CT systems

    International Nuclear Information System (INIS)

    Du, Louise Y; Umoh, Joseph; Nikolov, Hristo N; Pollmann, Steven I; Lee, Ting-Yim; Holdsworth, David W

    2007-01-01

    Small-animal imaging has recently become an area of increased interest because more human diseases can be modeled in transgenic and knockout rodents. As a result, micro-computed tomography (micro-CT) systems are becoming more common in research laboratories, due to their ability to achieve spatial resolution as high as 10 μm, giving highly detailed anatomical information. Most recently, a volumetric cone-beam micro-CT system using a flat-panel detector (eXplore Ultra, GE Healthcare, London, ON) has been developed that combines the high resolution of micro-CT and the fast scanning speed of clinical CT, so that dynamic perfusion imaging can be performed in mice and rats, providing functional physiological information in addition to anatomical information. This and other commercially available micro-CT systems all promise to deliver precise and accurate high-resolution measurements in small animals. However, no comprehensive quality assurance phantom has been developed to evaluate the performance of these micro-CT systems on a routine basis. We have designed and fabricated a single comprehensive device for the purpose of performance evaluation of micro-CT systems. This quality assurance phantom was applied to assess multiple image-quality parameters of a current flat-panel cone-beam micro-CT system accurately and quantitatively, in terms of spatial resolution, geometric accuracy, CT number accuracy, linearity, noise and image uniformity. Our investigations show that 3D images can be obtained with a limiting spatial resolution of 2.5 mm -1 and noise of ±35 HU, using an acquisition interval of 8 s at an entrance dose of 6.4 cGy

  16. Evaluation of aortocoronary bypass graft patency by reconstructed CT image

    International Nuclear Information System (INIS)

    Kawakita, Seizaburo; Koide, Takashi; Saito, Yoshio; Yamamoto, Tadao; Iwasaki, Tadaaki

    1982-01-01

    Ten patients were examined in the period of three months from January to March 1981. The patients were operated from 1 month to 7 years before CT. A bypass to the left anterior descending artery (LAD) was grafted in 10 cases, 2 to the right coronary artery (RCA), 4 to an obtuse marginal artery (OM), and 1 to a diagonal artery. Image reconstruction was performed in 10 cases by using an image analytical computer Evaluskop. Appropriate planes for reconstruction were selected by trial and error methods upon observation of CT images. When gained picture of a graft course coincided with surgical records or angiography, the work of building images was concluded. On cross section, grafts to LAD were visualized in all 10 cases: 9 in the entire course and 1 in a proximal part of the graft. Two to RCA, 4 to OM and 1 to a diagonal were also successfully visualized. Reconstruction of graft images succeeded in 9 grafts of 6 cases. The course of a graft could be pursued from the proximal to the distal end adjacent to the cardiac chamber. The picture of a bypass to LAD was visualized in 6 of 10 grafts. Two bypass to RCA could be depicted, and 1 to OM was also found. However 3 to OM and 1 to a diagonal failed to be visualized throughout their courses in reconstructed images. I think that the causes of faillure mainly depended upon the course of the graft. When a graft was running arc-like surrounding the heart chamber, it was very difficult to depict its entire length in reconstructed images, though the graft could be detected in cross sections. These preliminary studies indicated that reconstruction of CT images had some benefits for the pursuit of graft courses. (J.P.N.)

  17. TU-FG-BRB-01: Dual Energy CT Proton Stopping Power Ratio Calibration and Validation with Animal Tissues

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Y; Yin, L; Ainsley, C; McDonough, J; Solberg, T; Lin, A; Teo, B [University of Pennsylvania, Philadelphia, PA (United States)

    2016-06-15

    Purpose: The conversion of Hounsfield Unit (HU) to proton stopping power ratio (SPR) is a main source of uncertainty in proton therapy. In this study, the SPRs of animal tissues were measured and compared with prediction from dual energy CT (DECT) and single energy CT (SECT) calibrations. Methods: A stoichiometric calibration method for DECT was applied to predict the SPR using CT images acquired at 80 kVp and 140 kVp. The dual energy index was derived based on the HUs of the paired spectral images and used to calculate the SPRs of the materials. Tissue surrogates with known chemical compositions were used for calibration, and animal tissues (pig brain, liver, kidney; veal shank, muscle) were used for validation. The materials were irradiated with proton pencil beams, and SPRs were deduced from the residual proton range measured using a multi-layer ion chamber device. In addition, Gafchromic EBT3 films were used to measure the distal dose profiles after irradiation through the tissue samples and compared with those calculated by the treatment planning system using both DECT and SECT predicted SPRs. Results: The differences in SPR between DECT prediction and measurement were −0.31±0.36% for bone, 0.47±0.42% for brain, 0.67±0.15% for liver, 0.51±0.52% for kidney, and −0.96±0.15% for muscle. The corresponding results using SECT were 3.1±0.12%, 1.90±0.45%, −0.66±0.11%, 2.33±0.21%, and −1.70±0.17%. In the film measurements, average distances between film and calculated distal dose profiles were 0.35±0.12 mm for DECT calibration and −1.22±0.12 mm for SECT calibration for a beam with a range of 15.79 cm. Conclusion: Our study indicates that DECT is superior to SECT for proton SPR prediction and has the potential to reduce the range uncertainty to less than 2%. DECT may permit the use of tighter distal and proximal range uncertainty margins for treatment, thereby increasing the precision of proton therapy.

  18. Radiation dose reduction in soft tissue neck CT using adaptive statistical iterative reconstruction (ASIR)

    Energy Technology Data Exchange (ETDEWEB)

    Vachha, Behroze, E-mail: bvachha@partners.org [Neuroradiology Division, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA 02114 (United States); Brodoefel, Harald; Wilcox, Carol; Hackney, David B.; Moonis, Gul [Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215 (United States)

    2013-12-01

    Purpose: To compare objective and subjective image quality in neck CT images acquired at different tube current–time products (275 mA s and 340 mA s) and reconstructed with filtered-back-projection (FBP) and adaptive statistical iterative reconstruction (ASIR). Materials and methods: HIPAA-compliant study with IRB approval and waiver of informed consent. 66 consecutive patients were randomly assigned to undergo contrast-enhanced neck CT at a standard tube-current–time-product (340 mA s; n = 33) or reduced tube-current–time-product (275 mA s, n = 33). Data sets were reconstructed with FBP and 2 levels (30%, 40%) of ASIR-FBP blending at 340 mA s and 275 mA s. Two neuroradiologists assessed subjective image quality in a blinded and randomized manner. Volume CT dose index (CTDIvol), dose-length-product (DLP), effective dose, and objective image noise were recorded. Signal-to-noise ratio (SNR) was computed as mean attenuation in a region of interest in the sternocleidomastoid muscle divided by image noise. Results: Compared with FBP, ASIR resulted in a reduction of image noise at both 340 mA s and 275 mA s. Reduction of tube current from 340 mA s to 275 mA s resulted in an increase in mean objective image noise (p = 0.02) and a decrease in SNR (p = 0.03) when images were reconstructed with FBP. However, when the 275 mA s images were reconstructed using ASIR, the mean objective image noise and SNR were similar to those of the standard 340 mA s CT images reconstructed with FBP (p > 0.05). Subjective image noise was ranked by both raters as either average or less-than-average irrespective of the tube current and iterative reconstruction technique. Conclusion: Adapting ASIR into neck CT protocols reduced effective dose by 17% without compromising image quality.

  19. Radiation dose reduction in soft tissue neck CT using adaptive statistical iterative reconstruction (ASIR)

    International Nuclear Information System (INIS)

    Vachha, Behroze; Brodoefel, Harald; Wilcox, Carol; Hackney, David B.; Moonis, Gul

    2013-01-01

    Purpose: To compare objective and subjective image quality in neck CT images acquired at different tube current–time products (275 mA s and 340 mA s) and reconstructed with filtered-back-projection (FBP) and adaptive statistical iterative reconstruction (ASIR). Materials and methods: HIPAA-compliant study with IRB approval and waiver of informed consent. 66 consecutive patients were randomly assigned to undergo contrast-enhanced neck CT at a standard tube-current–time-product (340 mA s; n = 33) or reduced tube-current–time-product (275 mA s, n = 33). Data sets were reconstructed with FBP and 2 levels (30%, 40%) of ASIR-FBP blending at 340 mA s and 275 mA s. Two neuroradiologists assessed subjective image quality in a blinded and randomized manner. Volume CT dose index (CTDIvol), dose-length-product (DLP), effective dose, and objective image noise were recorded. Signal-to-noise ratio (SNR) was computed as mean attenuation in a region of interest in the sternocleidomastoid muscle divided by image noise. Results: Compared with FBP, ASIR resulted in a reduction of image noise at both 340 mA s and 275 mA s. Reduction of tube current from 340 mA s to 275 mA s resulted in an increase in mean objective image noise (p = 0.02) and a decrease in SNR (p = 0.03) when images were reconstructed with FBP. However, when the 275 mA s images were reconstructed using ASIR, the mean objective image noise and SNR were similar to those of the standard 340 mA s CT images reconstructed with FBP (p > 0.05). Subjective image noise was ranked by both raters as either average or less-than-average irrespective of the tube current and iterative reconstruction technique. Conclusion: Adapting ASIR into neck CT protocols reduced effective dose by 17% without compromising image quality

  20. Fast CT for evaluation of obstructive sleep apnea

    International Nuclear Information System (INIS)

    Stanson, A.W.; Sheedy, P.F.; Westbrook, P.R.; Shepard, J.W.; Welch, T.J.

    1988-01-01

    Sleep apnea affects 3%-4% of the adult male population. Fifty percent of these patients fail to respond to uvulopalatopharyngoplasty (UPP), which increases the patency of the oropharynx. Failure to respond to surgery may result from collapse in the hypopharynx. Fast CT (50-msec scan duration) was performed in 20 patients to demonstrate the regions of narrowing and collapsibility of the upper airway with tidal ventilation during wakefulness. While 67% of the patients showed narrowing ( 2 ) confined to the oropharynx, 33% additionally showed narrowing of the hypopharynx. Patients in this latter group may be poor candidates for UPP, which does not increase hypopharynx patience

  1. Current status of ultrafast CT to evaluate the left ventricle

    International Nuclear Information System (INIS)

    MacMillan, R.M.; Rees, M.R.; Maranhao, V.

    1987-01-01

    Contrast-enhanced ultrafast CT with the cine mode can enable reliable assessment of left ventricular mass and function. Two oblique planar views, the long axis and short axis, are required. Right and left ventricular end-diastolic volumes, end-systolic volumes, stroke volume and ejection fraction, left ventricular segmental wall motion, and left ventricular mass can be measured. This exhibit emphasizes the methods and pitfalls in acquiring this information. Results from the authors' studies thus far to validate these measurements against reference standards are reviewed

  2. Clinical utility of F-18 FDG PET-CT in the initial evaluation of lung cancer

    DEFF Research Database (Denmark)

    Madsen, Poul Henning; Holdgaard, Paw Christian; Buck Christensen, Janne

    2016-01-01

    the predefined criteria and were read in full to identify relevant original articles on F-18 FDG PET-CT (1) in the evaluation of solitary pulmonary nodules (n = 14), (2) in curative-intent treatment trials (n = 9), and (3) in planning of invasive procedures (n = 18). RESULTS: We found the following important...... results from the literature review: 1) PET-CT can rule out malignancy in most solitary pulmonary nodules due to high sensitivity (recommendation level A). 2) PET-CT reduces the number of futile treatment trials (recommendation level A). 3) The sensitivity of PET-CT in general is insufficient to rule out...... by CT in a structured programme. 2) No curative-intent treatment should be commenced until a PET-CT scan has excluded occult distant metastases. 3) In general, lymph node metastasis in the mediastinum cannot be ruled out on the basis of a negative PET-CT, and confirmative invasive staging should...

  3. Incremental Role of Mammography in the Evaluation of Gynecomastia in Men Who Have Undergone Chest CT.

    Science.gov (United States)

    Sonnenblick, Emily B; Salvatore, Mary; Szabo, Janet; Lee, Karen A; Margolies, Laurie R

    2016-08-01

    The purpose of this study was to determine whether additional breast imaging is clinically valuable in the evaluation of patients with gynecomastia incidentally observed on CT of the chest. In a retrospective analysis, 62 men were identified who had a mammographic diagnosis of gynecomastia and had also undergone CT within 8 months (median, 2 months). We compared the imaging findings of both modalities and correlated them with the clinical outcome. Gynecomastia was statistically significantly larger on mammograms than on CT images; however, there was a high level of concordance in morphologic features and distribution of gynecomastia between mammography and CT. In only one case was gynecomastia evident on mammographic but not CT images, owing to cachexia. Two of the 62 men had ductal carcinoma, which was obscured by gynecomastia. Both of these patients had symptoms suggesting malignancy. The appearance of gynecomastia on CT scans and mammograms was highly correlated. Mammography performed within 8 months of CT is unlikely to reveal cancer unless there is a suspicious clinical finding or a breast mass eccentric to the nipple. Men with clinical symptoms of gynecomastia do not need additional imaging with mammography to confirm the diagnosis if they have undergone recent cross-sectional imaging.

  4. Post-mortem CT evaluation of atlanto-occipital dissociation.

    Science.gov (United States)

    Madadin, Mohammed; Samaranayake, Ravindra Priyalal; O'Donnell, Chris; Cordner, Stephen

    2017-02-01

    Atlanto-occipital dissociation injury is an important injury in forensic pathology practice. Radiological diagnosis of atlanto-occipital dissociation clinically is assessed by direct measurement of occipito-vertebral skeletal relationships. Different measurements may be used to diagnose atlanto-occipital dissociation, including the basion-dens interval (BDI) and basion-axial interval (BAI). It is not known whether the normal ante-mortem measurements of BDI and BAI described in the literature are applicable to post-mortem CT images of the occipito-cervical junction (OCJ) or whether these measurements could be affected by early post-mortem changes. This study aims to compare post-mortem BDI and BAI measurements with ante-mortem values. Post-mortem CT scans of the cervical spines of 100 deceased adults were reviewed, and the BDI and BAI were measured. Different parameters were recorded in each case. The results from this study suggest that there are no effects of post-mortem changes on the measurement of BAI as relied upon clinically. There appear to be some effects of fully established rigor mortis on BDI measurement, shortening it. This may have consequences for the post mortem diagnosis of atlanto-occipital dissociation. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  5. Lymph node metastasis in the biliary tract carcinoma: CT evaluation

    International Nuclear Information System (INIS)

    Lee, Byung Hee; Lee, Ah Ra; Kim, Kie Hwan; Do, Young Soo; Chin, Soo Yil

    1994-01-01

    The primary biliary carcinoma is usually unresectable at presentation, because of early lymphatic spread. To determine the incidence and the spread pattern of lymph node metastases according to the location of the primary tumor, we analyzed the CT scans of the patients with primary biliary adenocarcinoma. We reviewed the CT scans of 92 patients with pathologically proven primary biliary adenocacinima, including 45 peripheral cholangiocarcinomas, 22 hilar cholangiocarcinomas, 18 gallbladder carcinomas, and 7 common bile duct carcinomas. Positive adenopathy was diagnosed when the node exceeded 10 mm in short axis. The overall incidence of nodal metastases was 59.8% (55/92); 66.7% in peripheral cholangiocarcinoma, 54.5% in hilar cholangiocarcinoma, 55.6% in gallbladder carcinoma, and 42.9% in common bile duct carcinoma. The most commonly involved nodal group was the lesser omentum, followed by the celiac, periaortic, and peripancreatic group. The phrenic node group was only involved in the cases with the peripheral or hilar cholangiocarcinoma. The primary biliary carcinoma has a high incidence of lymph node metastases at the time of diagnosis, and shows different nodal spread pattern according to the location of the primary tumor. Involvement of the phrenic node was limited to the peripheral and hilar cholangiocarcinoma

  6. Lymph node metastasis in the biliary tract carcinoma: CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Hee; Lee, Ah Ra; Kim, Kie Hwan; Do, Young Soo; Chin, Soo Yil [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1994-07-15

    The primary biliary carcinoma is usually unresectable at presentation, because of early lymphatic spread. To determine the incidence and the spread pattern of lymph node metastases according to the location of the primary tumor, we analyzed the CT scans of the patients with primary biliary adenocarcinoma. We reviewed the CT scans of 92 patients with pathologically proven primary biliary adenocacinima, including 45 peripheral cholangiocarcinomas, 22 hilar cholangiocarcinomas, 18 gallbladder carcinomas, and 7 common bile duct carcinomas. Positive adenopathy was diagnosed when the node exceeded 10 mm in short axis. The overall incidence of nodal metastases was 59.8% (55/92); 66.7% in peripheral cholangiocarcinoma, 54.5% in hilar cholangiocarcinoma, 55.6% in gallbladder carcinoma, and 42.9% in common bile duct carcinoma. The most commonly involved nodal group was the lesser omentum, followed by the celiac, periaortic, and peripancreatic group. The phrenic node group was only involved in the cases with the peripheral or hilar cholangiocarcinoma. The primary biliary carcinoma has a high incidence of lymph node metastases at the time of diagnosis, and shows different nodal spread pattern according to the location of the primary tumor. Involvement of the phrenic node was limited to the peripheral and hilar cholangiocarcinoma.

  7. Evaluation of the OSC-TV iterative reconstruction algorithm for cone-beam optical CT.

    Science.gov (United States)

    Matenine, Dmitri; Mascolo-Fortin, Julia; Goussard, Yves; Després, Philippe

    2015-11-01

    The present work evaluates an iterative reconstruction approach, namely, the ordered subsets convex (OSC) algorithm with regularization via total variation (TV) minimization in the field of cone-beam optical computed tomography (optical CT). One of the uses of optical CT is gel-based 3D dosimetry for radiation therapy, where it is employed to map dose distributions in radiosensitive gels. Model-based iterative reconstruction may improve optical CT image quality and contribute to a wider use of optical CT in clinical gel dosimetry. This algorithm was evaluated using experimental data acquired by a cone-beam optical CT system, as well as complementary numerical simulations. A fast GPU implementation of OSC-TV was used to achieve reconstruction times comparable to those of conventional filtered backprojection. Images obtained via OSC-TV were compared with the corresponding filtered backprojections. Spatial resolution and uniformity phantoms were scanned and respective reconstructions were subject to evaluation of the modulation transfer function, image uniformity, and accuracy. The artifacts due to refraction and total signal loss from opaque objects were also studied. The cone-beam optical CT data reconstructions showed that OSC-TV outperforms filtered backprojection in terms of image quality, thanks to a model-based simulation of the photon attenuation process. It was shown to significantly improve the image spatial resolution and reduce image noise. The accuracy of the estimation of linear attenuation coefficients remained similar to that obtained via filtered backprojection. Certain image artifacts due to opaque objects were reduced. Nevertheless, the common artifact due to the gel container walls could not be eliminated. The use of iterative reconstruction improves cone-beam optical CT image quality in many ways. The comparisons between OSC-TV and filtered backprojection presented in this paper demonstrate that OSC-TV can potentially improve the rendering of

  8. Comparing CT perfusion with oxygen partial pressure in a rabbit VX2 soft-tissue tumor model.

    Science.gov (United States)

    Sun, Chang-Jin; Li, Chao; Lv, Hai-Bo; Zhao, Cong; Yu, Jin-Ming; Wang, Guang-Hui; Luo, Yun-Xiu; Li, Yan; Xiao, Mingyong; Yin, Jun; Lang, Jin-Yi

    2014-01-01

    The aim of this study was to evaluate the oxygen partial pressure of the rabbit model of the VX2 tumor using a 64-slice perfusion CT and to compare the results with that obtained using the oxygen microelectrode method. Perfusion CT was performed for 45 successfully constructed rabbit models of a VX2 brain tumor. The perfusion values of the brain tumor region of interest, the blood volume (BV), the time to peak (TTP) and the peak enhancement intensity (PEI) were measured. The results were compared with the partial pressure of oxygen (PO2) of that region of interest obtained using the oxygen microelectrode method. The perfusion values of the brain tumor region of interest in 45 successfully constructed rabbit models of a VX2 brain tumor ranged from 1.3-127.0 (average, 21.1 ± 26.7 ml/min/ml); BV ranged from 1.2-53.5 ml/100g (average, 22.2 ± 13.7 ml/100g); PEI ranged from 8.7-124.6 HU (average, 43.5 ± 28.7 HU); and TTP ranged from 8.2-62.3 s (average, 38.8 ± 14.8 s). The PO2 in the corresponding region ranged from 0.14-47 mmHg (average, 16 ± 14.8 mmHg). The perfusion CT positively correlated with the tumor PO2, which can be used for evaluating the tumor hypoxia in clinical practice.

  9. A comparative study between subjective assessment and quantitative evaluation of CT findings with cerebral palsy

    International Nuclear Information System (INIS)

    Sugie, Yoko; Sugie, Hideo; Kitai, Akiko; Maruyama, Hiroshi; Fukuyama, Yukio

    1982-01-01

    Computed tomography (CT) was performed on 200 children with children palsy with Hitachi CT-H250. The CT scans of 136 cases revealed cerebral atrophy with ventricular and/or subarachnoid space enlargement. The lateral ventricles, the third ventricle and the two parts of subarachnoid space on the CT picture were subjectively evaluated and divided into five grades ranging from no enlargement to marked enlargement. In addition, the size of the ventricles and the subarachnoid spaces were quantitatively determined; the transverse diameter of brain (b), the largest width of the anterior horns of the lateral ventricles (c), the bicaudate nuclear distance (d), the greatest width of the third ventricle, the longitudinal cerebral fissure and sylvian fissures as described by Miyao et al. (1978). Comparison of these quantitative techniques confirmed the initial subjective evaluation. However, in some cases, amendment of the subjective evaluation was needed. As mentioned before (Miyao et al.), the cerebral longitudinal fissure was relatively wide in normal infants. Accordingly, it was often difficult to find out abnormal widening only by subjective evaluation. The purpose of this paper was to establish the criteria of quantitative measuring and assessing of the lateral and third ventricles, the cerebral longitudinal fissurem, and the sylvian fissures enlargement. Interpretation of some problem cases associated with measuring was also discussed. The quantitative CT evaluation may be a good reference in assessing cerebral atrophy in cerebral palsy and other neurological diseases. (author)

  10. Dental flat panel conebeam CT in the evaluation of patients with inflammatory sinonasal disease: Diagnostic efficacy and radiation dose savings.

    Science.gov (United States)

    Leiva-Salinas, C; Flors, L; Gras, P; Más-Estellés, F; Lemercier, P; Patrie, J T; Wintermark, M; Martí-Bonmatí, L

    2014-01-01

    CT is the imaging modality of choice to study the paranasal sinuses; unfortunately, it involves significant radiation dose. Our aim was to assess the diagnostic validity, image quality, and radiation-dose savings of dental conebeam CT in the evaluation of patients with suspected inflammatory disorders of the paranasal sinuses. We prospectively studied 40 patients with suspected inflammatory disorders of the sinuses with dental conebeam CT and standard CT. Two radiologists analyzed the images independently, blinded to clinical information. The image quality of both techniques and the diagnostic validity of dental conebeam CT compared with the reference standard CT were assessed by using 3 different scoring systems. Image noise, signal-to-noise ratio, and contrast-to-noise ratio were calculated for both techniques. The absorbed radiation dose to the lenses and thyroid and parotid glands was measured by using a phantom and dosimeter chips. The effective radiation dose for CT was calculated. All dental conebeam CT scans were judged of diagnostic quality. Compared with CT, the conebeam CT image noise was 37.3% higher (P radiation dose to the lenses and parotid and thyroid glands with conebeam CT was 4%, 7.8%, and 7.3% of the dose delivered to the same organs by conventional CT (P Dental conebeam CT is a valid imaging procedure for the evaluation of patients with inflammatory sinonasal disorders. © 2014 by American Journal of Neuroradiology.

  11. Evaluation of radiation dose in 64-row whole-body CT of multiple injured patients compared to 4-row CT

    International Nuclear Information System (INIS)

    Harrieder, A.; Geyer, L.L.; Koerner, M.; Deak, Z.; Wirth, S.; Reiser, M.; Linsenmaier, U.

    2012-01-01

    Purpose: To evaluate radiation exposure in whole-body CT (WBCT) of multiple injured patients comparing 4-row multidetector computed tomography (MDCT) to 64-row MDCT. Materials and Methods: 200 WBCT studies were retrospectively evaluated: 92 4-row MDCT scans and 108 64-row MDCT scans. Each CT protocol was optimized for the particular CT system. The scan length, CT dose index (CTDI), and dose length product (DLP) were recorded and analyzed for radiation exposure. The mean effective dose was estimated based on conversion factors. Student's t-test was used for statistical analysis. Results: The mean CTDI vol values (mGy) of the thorax and abdomen were significantly reduced with 64-row MDCT (10.2 ± 2.5 vs. 11.4 ± 1.4, p < 0.001; 14.2 ± 3.7 vs. 16.1 ± 1.7, p < 0.001). The DLP values (mGy x cm) of the head and thorax were significantly increased with 64-row MDCT (1305.9 ± 201.1 vs. 849.8 ± 90.9, p < 0,001; 504.4 ± 134.4 vs. 471.5 ± 74.1, p = 0.030). The scan lengths (mm) were significantly increased with 64-row MDCT: head 223.6 ± 35.8 vs. 155.5 ± 12.3 (p < 0.001), thorax 427.4 ± 44.5 vs. 388.3 ± 57.5 (p < 0.001), abdomen 520.3 ± 50.2 vs. 490.8 ± 51.6 (p < 0.001). The estimated mean effective doses (mSv) were 22.4 ± 2.6 (4-row MDCT) and 24.1 ± 4.6 (64-row MDCT; p = 0.001), resulting in a percentage increase of 8 %. Conclusion: The radiation dose per slice of the thorax and abdomen can be significantly decreased by using 64-row MDCT. Due to the technical advances of modern 64-row MDCT systems, the scan field can be adapted to the clinical demands and, if necessary, enlarged without time loss. As a result, the estimated mean effective dose might be increased in WBCT. (orig.)

  12. Evaluation of Image Quality in Low Tube-Voltage Chest CT Scan

    International Nuclear Information System (INIS)

    Kim, Hyun Ju; Cho, Jae Hwan; Park, Cheol Soo

    2010-01-01

    The patients who visited this department for pulmonary disease and need CT scans for Follow-up to observe change of CT value, evaluation of image quality and decrease of radiation dose as change of kVp. Subjects were the patients of 20 persons visited this department for pulmonary disease and Somatom Sensation 16(Semens, Enlarge, Germany) was used. Measurement of CT value as change of kVp was done by setting up ROI diameter of 1cm at the height of thyroid, aortic arch, right pulmonary artery in arterial phase image using 100 kVp, measuring 3 times, and recorded the average. CT value of phantom was measured by scanning phantoms which means contrast media diluted by normal saline by various ratio with tube voltage of 80 kVp, 100 kVp, 120 kVp, 140 kVp and recorded the average of 3 CT values of center of phantom image. In analysing radiation dose, CTDIVOL values of the latest arterial phase image of 120 kVp and as this research set that of 100 kVp were analyzed comparatively. 2 observers graded quality of chest images by 5 degrees (Unacceptable, Suboptimal, Adequate, Good, Excellent). CT value of chest image increased at 100 kVp by 14.06%∼27.26% in each ROI than 120 kVp. CT value of phantom increased as tube voltage lowered at various concentration of contrast media. CTDIVOL decreased at 100 kVp(5.00 mGy) by 36% than 120 kVp(7.80 mGy) in radiation dose analysis. here were 0 Unacceptable, 1 Suboptimal, 3 Adequate, 10 Good, 6 Excellent in totally 20 persons. Chest CT scanning with low kilo-voltage for patients who need CT scan repeatedly can bring images valuable for diagnose, and decrease radiation dose against patients

  13. Understanding biomaterial-tissue interface quality: combined in vitro evaluation

    Science.gov (United States)

    Gasik, Michael

    2017-12-01

    One of the greatest challenges in the development of new medical products and devices remains in providing maximal patient safety, efficacy and suitability for the purpose. A 'good quality' of the tissue-implant interface is one of the most critical factors for the success of the implant integration. In this paper this challenge is being discussed from the point of view of basic stimuli combination to experimental testing. The focus is in particular on bacterial effects on tissue-implant interaction (for different materials). The demonstration of the experimental evaluation of the tissue-implant interface is for dental abutment with mucosal contact. This shows that testing of the interface quality could be the most relevant in controlled conditions, which mimic as possible the clinical applications, but consider variables being under the control of the evaluator.

  14. Micro-CT evaluation and histological analysis of screw-bone interface of expansive pedicle screw in osteoporotic sheep.

    Science.gov (United States)

    Wan, Shi-yong; Lei, Wei; Wu, Zi-xiang; Lv, Rong; Wang, Jun; Fu, Suo-chao; Li, Bo; Zhan, Ce

    2008-04-01

    To investigate the properties of screw-bone interface of expansive pedicle screw (EPS) in osteoporotic sheep by micro-CT and histological observation. Six female sheep with bilateral ovariectomy-induced osteoporosis were employed in this experiment. After EPS insertion in each femoral condyle, the sheep were randomly divided into two groups: 3 sheep were bred for 3 months (Group A), while the other 3 were bred for 6 months (Group B). After the animals being killed, the femoral condyles with EPS were obtained, which were three-dimensionally-imaged and reconstructed by micro-CT. Histological evaluation was made thereafter. The trabecular microstructure was denser at the screw-bone interface than in the distant parts in expansive section, especially within the spiral marking. In the non-expansive section, however, there was no significant difference between the interface and the distant parts. The regions of interest (ROI) adjacent to EPS were reconstructed and analyzed by micro-CT with the same thresholds. The three-dimensional (3-D) parameters, including tissue mineral density (TMD), bone volume fraction (BVF, BV/TV), bone surface/bone volume (BS/BV) ratio, trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp), were significantly better in expansive sections than non-expansive sections (P less than 0.05). Histologically, newly-formed bony trabeculae crawled along the expansive fissures and into the center of EPS. The newly-formed bones, as well as the bones at the bone-screw interface, closely contacted with the EPS and constructed four compartments. The findings of the current study, based on micro-CT and histological evaluation, suggest that EPS can significantly provide stabilization in osteoporotic cancellous bones.

  15. Accuracy evaluation of fusion of CT, MR, and SPECT images using commercially available software packages (SRS PLATO and IFS)

    International Nuclear Information System (INIS)

    Mongioj, Valeria; Brusa, Anna; Loi, Gianfranco; Pignoli, Emanuele; Gramaglia, Alberto; Scorsetti, Marta; Bombardieri, Emilio; Marchesini, Renato

    1999-01-01

    Purpose: A problem for clinicians is to mentally integrate information from multiple diagnostic sources, such as computed tomography (CT), magnetic resonance (MR), and single photon emission computed tomography (SPECT), whose images give anatomic and metabolic information. Methods and Materials: To combine this different imaging procedure information, and to overlay correspondent slices, we used commercially available software packages (SRS PLATO and IFS). The algorithms utilize a fiducial-based coordinate system (or frame) with 3 N-shaped markers, which allows coordinate transformation of a clinical examination data set (9 spots for each transaxial section) to a stereotactic coordinate system. The N-shaped markers were filled with fluids visible in each modality (gadolinium for MR, calcium chloride for CT, and 99m Tc for SPECT). The frame is relocatable, in the different acquisition modalities, by means of a head holder to which a face mask is fixed so as to immobilize the patient. Position errors due to the algorithms were obtained by evaluating the stereotactic coordinates of five sources detectable in each modality. Results: SPECT and MR position errors due to the algorithms were evaluated with respect to CT: Δx was ≤ 0.9 mm for MR and ≤ 1.4 mm for SPECT, Δy was ≤ 1 mm and ≤ 3 mm for MR and SPECT, respectively. Maximal differences in distance between estimated and actual fiducial centers (geometric mismatch) were in the order of the pixel size (0.8 mm for CT, 1.4 mm for MR, and 1.8 mm for SPECT). In an attempt to distinguish necrosis from residual disease, the image fusion protocol was studied in 35 primary or metastatic brain tumor patients. Conclusions: The image fusion technique has a good degree of accuracy as well as the potential to improve the specificity of tissue identification and the precision of the subsequent treatment planning

  16. Evaluation of thymic tumors with 18F-FDG PET-CT - A pictorial review

    International Nuclear Information System (INIS)

    Sharma, Punit; Singhal, Abhinav; Bal, Chandrasekhar; Malhotra, Arun; Kumar, Rakesh; Kumar, Arvind

    2013-01-01

    Thymic tumors represent a broad spectrum of neoplastic disorders and pose considerable diagnostic difficulties. A non-invasive imaging study to determine the nature of thymic lesions can have significant impact on management of such tumors. 18F-flurorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) has shown promising results in characterization of thymic tumors. The objective of this article is to provide an illustrative tutorial highlighting the clinical utility of 18F-FDG PET-CT imaging in patients with thymic tumors. We have pictorially depicted the 18F-FDG PET-CT salient imaging characteristics of various thymic tumors, both epithelial and non-epithelial. Also discussed is the dynamic physiology of thymus gland which is to be kept in mind when evaluating thymic pathology on 18F-FDG PET-CT, as it can lead to interpretative pitfalls

  17. Evaluation of the Meditech M250 and a comparison with other CT scanners

    Energy Technology Data Exchange (ETDEWEB)

    Greensmith, R.; Richardson, R.B.; Mackintosh, I.P.; Sargood, A.J.; Stevens, P.H.

    1985-11-01

    The Meditech M250 computerised tomography (CT) machine was evaluated during the first half of 1984. Measurements were made of noise, modulation transfer function, slice width, radiation dose profile, uniformity and linearity of CT number, effective photon energy and parameters relating to machine specification, such as pixel size and scan time. All breakdowns were logged to indicate machine reliability. A comparison with the established EMI CT1010 and CT5005 was made for noise, resolution and multislice radiation dose, as well as the dose efficiency or quality (Q) factor for both head and body modes of operation. The M250 was found to perform to its intended specification with an acceptable level of reliability.

  18. An evaluation of the Meditech M250 and a comparison with other CT scanners

    International Nuclear Information System (INIS)

    Greensmith, R.; Richardson, R.B.; Mackintosh, I.P.; Sargood, A.J.; Stevens, P.H.

    1985-01-01

    The Meditech M250 computerised tomography (CT) machine was evaluated during the first half of 1984. Measurements were made of noise, modulation transfer function, slice width, radiation dose profile, uniformity and linearity of CT number, effective photon energy and parameters relating to machine specification, such as pixel size and scan time. All breakdowns were logged to indicate machine reliability. A comparison with the established EMI CT1010 and CT5005 was made for noise, resolution and multislice radiation dose, as well as the dose efficiency or quality (Q) factor for both head and body modes of operation. The M250 was found to perform to its intended specification with an acceptable level of reliability. (author)

  19. An evaluation of the Meditech M250 and a comparison with other CT scanners.

    Science.gov (United States)

    Greensmith, R; Richardson, R B; Sargood, A J; Stevens, P H; Mackintosh, I P

    1985-11-01

    The Meditech M250 computerised tomography (CT) machine was evaluated during the first half of 1984. Measurements were made of noise, modulation transfer function, slice width, radiation dose profile, uniformity and linearity of CT number, effective photon energy and parameters relating to machine specification, such as pixel size and scan time. All breakdowns were logged to indicate machine reliability. A comparison with the established EMI CT1010 and CT5005 was made for noise, resolution and multislice radiation dose, as well as the dose efficiency or quality (Q) factor for both head and body modes of operation. The M250 was found to perform to its intended specification with an acceptable level of reliability.

  20. Clinical application of subtraction CT imaging for evaluation of pulmonary vascular permeability

    International Nuclear Information System (INIS)

    Kato, Shiro; Asai, Toshihiko; Yatagai, Shigeo; Oonuma, Noboru; Ohno, Kunihiko; Nakamoto, Takaaki; Iizuka, Masahiko

    1991-01-01

    In this clinical study, one normal subject, one patient with primary interstitial pneumonia, one patient with segmental pneumonia due to Staphylococcus aureus, one patient with post-operative esophageal carcinoma, and two patients with mitral stenosis were studied. Dynamic CT scan images under continuous injection of low osmotic contrast medium were analyzed in series, in an attempt to evaluate vascular permeability quantitatively. The following results were obtained. Subtraction CT scan image 10 minutes after the start of contrast medium injection in two patients with pneumonia, showed a reduction of pulmonary vascular permeability following therapy. Subtraction CT scan image of the patient with post-operative esophageal carcinoma treated with 25 Gy radiation showed a discrepancy between pulmonary vascular permeability and other findings. In hemodynamically stable patients with mitral stenosis, subtraction CT images demonstrated that pulmonary vascular permeability was not affected by pulmonary congestion, irrespective of its severity. (author)

  1. Clinical experience of titanium cerebral aneurysm clips. Evaluation of artifact of CT and MRI

    International Nuclear Information System (INIS)

    Ninomiya, Takashi; Kato, Yoko; Sano, Hirotoshi

    1996-01-01

    The titanium aneurysm clips manufactured by AESCULAP Company are expected to be useful, not only for clinical applications, but also for reducing artifacts in post-operative CT and MRI. We carried out an investigation of the behavior of the new Yasargil titanium clips in a 1.5T MR imager. The new titanium clips showed considerably smaller clip-induced MR and CT artifacts than phynox and elgiloy clips. No movement of the titanium clips was seen by introducing them to the MR imager. Subsequent to these experimental studies, we applied titanium clips to 25 cerebral aneurysms. Post-operative CT, especially helical scanning CT and MR showed minimal artifacts, leading to the conclusion that the titanium clips are better than the other types of clips for the evaluation of post-operative neuroradiological images. (author)

  2. Clinical evaluation of dual-energy bone removal in CT angiography of the head and neck: comparison with conventional bone-subtraction CT angiography

    International Nuclear Information System (INIS)

    Deng, K.; Liu, C.; Ma, R.; Sun, C.; Wang, X.-M.; Ma, Z.-T.; Sun, X.-L.

    2009-01-01

    Aim: To evaluate the bone-subtraction effect of dual-energy bone removal in computed tomography angiography (CTA) of the head and neck in comparison with conventional bone-subtraction CTA. Material and Methods: The study comprised 52 patients who were divided into two groups at random, and examined using dual-source CT for head and neck CTA. Dual-energy bone removal CTA and conventional bone-subtraction CTA were applied to each of the two groups, respectively. The bone subtraction was performed automatically in both methods. Vascular structures, as well as brain tissue remained visible. The subtracted images were further processed with maximum intensity projection (MIP) and volume-rendering technique (VRT) for image evaluation. Two experienced radiologists reviewed the resulting subtracted and non-subtracted volume data with respect to the delineation and detection of image quality and vascular pathology. Results: The means of the weighted CT dose index (CTDIvol) for bone-removal dual-energy CTA and conventional bone-subtraction CTA were 20.56 ± 0.01 mGy and 25.57 ± 0.56 mGy, respectively. There was a significant difference between them. The percentage of carotid and vertebral arteries and all other vessels that could be successfully assessed with these two methods were 87.8, 68, and 83%, and 93.5, 91.8, and 92.6%, respectively. There were no significant differences in the visualization of the carotid arteries; however, there were significant differences in the visualization of the vertebral arteries. Conclusion: Compared with conventional bone-subtraction CTA, dual-energy bone-removal CTA had a lower radiation dose. It eliminated most bones in the head and neck successfully; however, the bone subtraction effect around the vertebral artery was unsatisfactory. Dual-energy bone-removal CTA provides a new method for detecting vascular diseases in routine clinical work.

  3. The Relationship between Brown Adipose Tissue Activity and Neoplastic Status: an 18F-FDG PET/CT Study in the Tropics

    Directory of Open Access Journals (Sweden)

    Huang Yung-Cheng

    2011-12-01

    Full Text Available Abstract Background Brown adipose tissue (BAT has thermogenic potential. For its activation, cold exposure is considered a critical factor though other determinants have also been reported. The purpose of this study was to assess the relationship between neoplastic status and BAT activity by 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG positron emission tomography/computed tomography (PET/CT in people living in the tropics, where the influence of outdoor temperature was low. Methods 18F-FDG PET/CT scans were reviewed and the total metabolic activity (TMA of identified activated BAT quantified. The distribution and TMA of activated BAT were compared between patients with and without a cancer history. The neoplastic status of patients was scored according to their cancer history and 18F-FDG PET/CT findings. We evaluated the relationships between the TMA of BAT and neoplastic status along with other factors: age, body mass index, fasting blood sugar, gender, and outdoor temperature. Results Thirty of 1740 patients had activated BAT. Those with a cancer history had wider BAT distribution (p = 0.043 and a higher TMA (p = 0.028 than those without. A higher neoplastic status score was associated with a higher average TMA. Multivariate analyses showed that neoplastic status was the only factor significantly associated with the TMA of activated BAT (p = 0.016. Conclusions Neoplastic status is a critical determinant of BAT activity in patients living in the tropics. More active neoplastic status was associated with more vigorous TMA of BAT.

  4. Feasibility and clinical value of CT-guided {sup 125}I brachytherapy for metastatic soft tissue sarcoma after first-line chemotherapy failure

    Energy Technology Data Exchange (ETDEWEB)

    Mo, Zhiqiang; Zhang, Yanling; Xiang, Zhanwang; Yan, Huzhen; Zhong, Zhihui; Gao, Fei; Zhang, Fujun [Sun Yat-Sen University Cancer Centre, State Key Laboratory of Oncology in South China, Collaborative Innovation Centre for Cancer Medicine, Guangzhou (China); Zhang, Tao [Guangzhou Medical University, Department of Interventional Radiology and Vascular Anomalies, Guangzhou Women and Children' s Medical Centre, Guangzhou (China)

    2018-03-15

    To evaluate the feasibility and usefulness of computed tomography (CT