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Sample records for ct attenuation values

  1. Pleural effusion: characterization with CT attenuation values and CT appearance.

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    Abramowitz, Yigal; Simanovsky, Natalia; Goldstein, Michael S; Hiller, Nurith

    2009-03-01

    The purpose of this study was to assess the utility of CT in characterizing pleural effusions on the basis of attenuation values and CT appearance. We retrospectively analyzed 100 pleural effusions in patients who underwent chest CT and diagnostic thoracentesis within 48 hours of each other. On the basis of Light's criteria, effusions were classified as exudates or transudates using laboratory biochemistry markers. The mean value in Hounsfield units of an effusion was determined using a region of interest on the three slices with the greatest quantity of fluid. All CT scans also were reviewed for the presence of additional pleural features such as fluid loculation, pleural thickening, and pleural nodules. Twenty-two of the 100 pleural effusions were transudates and 78 were exudates. The mean attenuation of the exudates (7.2 HU; [SD] 9.4 HU; range, 21-28 HU) was not significantly lower than the mean attenuation of the transudates (10.1 HU; 6.9 HU; range, 0.3-32 HU), (p = 0.24). None of the additional CT features accurately differentiated exudates from transudates (p > 0.1). Fluid loculation was found in 58% of exudates and in 36% of transudates. Pleural thickening was found in 59% of exudates and in 36% of transudates. The clinical use of CT attenuation values to characterize pleural fluid is not accurate. Although fluid loculation, pleural thickness, and pleural nodules were more commonly found in patients with exudative effusions, the presence of these features does not accurately differentiate between exudates and transudates.

  2. Efficacy of Computed Tomography (CT) Attenuation Values and CT Findings in the Differentiation of Pleural Effusion

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    Yalçin-Şafak, Kadihan; Umarusman-Tanju, Neslihan; Ayyıldız, Muhammet; Yücel, Nihal; Baysal, Tamer

    2017-01-01

    Summary Background The aim of this study was to investigate the efficacy of computed tomography (CT) findings for characterizing pleural effusions with the use of attenuation values. Material/Methods One hundred and twenty eight patients with pleural effusions on thoracic CT who underwent thoracentesisis within two weeks were studied. Pleural effusions were classified as exudates or transudates according to the Light’s criteria. A region of interest was placed for the measurement of Hounsfield Unit (HU) values in the area of the greatest amount of effusion on each slice of the three slices used. CT features that were evaluated for distinguishing pleural exudates from transudates included pleural nodules, pleural thickening and loculation. Results Thirty three (26%) of the 128 pleural effusions were transudates and 95 (74%) were exudates. The mean HU values of the exudates (8.82±7.04) were significantly higher than those of the transudates (2.91±8.53), (ptransudate and exudate patients in terms of pleural thickness, pleural nodules and loculation (p>0.05). Conclusions HU values can help in differentiating exudative pleural effusions from transudative pleural effusions. Because of overlapping HU values, correlation with clinical findings is essential. PMID:28289482

  3. Prognostic significance of contrast-enhanced CT attenuation value in extrahepatic cholangiocarcinoma

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    Asayama, Yoshiki [Kyushu University, Department of Advanced Imaging and Interventional Radiology, Graduate School of Medical Sciences, Fukuoka (Japan); Nishie, Akihiro; Ishigami, Kousei; Ushijima, Yasuhiro; Takayama, Yukihisa; Okamoto, Daisuke; Fujita, Nobuhiro; Honda, Hiroshi [Kyushu University, Departments of Clinical Radiology, Fukuoka (Japan); Ohtsuka, Takao [Kyushu University, Departments of Surgery and Oncology, Fukuoka (Japan); Yoshizumi, Tomoharu [Kyushu University, Departments of Surgery and Sciences, Fukuoka (Japan); Aishima, Shinichi [Saga University, Pathology and Microbiology, Faculty of Medicine, Saga (Japan); Kyushu University, Departments of Anatomic Pathology, Graduate School of Medical Sciences, Fukuoka (Japan); Oda, Yoshinao [Kyushu University, Departments of Anatomic Pathology, Graduate School of Medical Sciences, Fukuoka (Japan)

    2017-06-15

    To determine whether washout characteristics of dynamic contrast-enhanced computed tomography (CT) could predict survival in patients with extrahepatic cholangiocarcinoma (EHC). This study collected 46 resected cases. All cases were examined by dynamic contrast study on multidetector-row CT. Region-of-interest measurements were obtained at the non-enhanced, portal venous phase and delayed phase in the tumour and were used to calculate the washout ratio as follows: [(attenuation value at portal venous phase CT - attenuation value at delayed enhanced CT)/(attenuation value at portal venous phase CT - attenuation value at unenhanced CT)] x 100. On the basis of the median washout ratio, we classified the cases into two groups, a high-washout group and low-washout group. Associations between overall survival and various factors including washout rates were analysed. The median washout ratio was 29.4 %. Univariate analysis revealed that a lower washout ratio, venous invasion, lymphatic permeation and lymph node metastasis were associated with shorter survival. Multivariate analysis identified the lower washout ratio as an independent prognostic factor (hazard ratio, 3.768; p value, 0.027). The washout ratio obtained from the contrast-enhanced CT may be a useful imaging biomarker for the prediction of survival of patients with EHC. (orig.)

  4. The Value of CT Attenuation in Distinguishing Atypical Adenomatous Hyperplasia from Adenocarcinoma in Situ

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    Binghu JIANG

    2013-11-01

    Full Text Available Background and objective: Advances in high-resolution computed tomography (CT scanning have increased the detection of small ground-glass opacity (GGO nodules and also allowed such images to be investigated in detail. However, it is difficult to differentiate atypical adenomatous hyperplasia (AAH from adenocarcinoma in situ (AIS with CT, even at follow-up, because they share many similar CT manifestations. While AAH is thought to be a precursor or even an early-stage lesion of lung adenocarcinoma, and the stepwise progression from AAH to AIS is thought to be reasonable. Therefore, the hypothesis that the attenuation of GGO is increased gradually from AAH to AIS is proposed. The aim of this study was to distinguish AAH from AIS with CT attenuation in patients with pure GGO nodules. 
Methods: Between January 2010 and December 2012, the CT findings in terms of the greatest diameter and mean CT attenuation (HU were reviewed and correlated with pathology in 56 patients with AAH (n=21 and non-mucinous AIS (n=38 by two independent observers. All the 59 lesions were pure GGO nodules with size of 2 cm or smaller. To determine variability of measuring CT attenuation, we calculated the 95% confidence interval (CI for the limits of agreement by using Bland-Altman analysis. Student t test was used to compare AAH and AIS in terms of diameter and CT attenuation. And receiver operating characteristic (ROC curve was used to determine the optimal cut-off value of mean CT attenuation for differentiating AAH from AIS and obtain the diagnostic value. Two-tailed P value of less than 0.05 was considered to be significant. 
Results: For the manually measured CT attenuation, the 95%CI for the limits of agreement was -40 HU, 50 HU for inter-observer variability. Although there was significant difference in nodule diameter between AAH and AIS (P=0.046, the overlap was considerable. The mean CT attenuation was (-718±53 HU (95%CI: -822, -604 for AAH, which was

  5. The Value of CT Attenuation in Distinguishing Atypical Adenomatous Hyperplasia from Adenocarcinoma in Situ

    Institute of Scientific and Technical Information of China (English)

    Binghu JIANG; Jichen WANG; Peng JIA; Meizhao LE

    2013-01-01

    Background and objective:Advances in high-resolution computed tomography (CT) scanning have increased the detection of small ground-glass opacity (GGO) nodules and also allowed such images to be investigated in detail. However, it is diffcult to differentiate atypical adenomatous hyperplasia (AAH) from adenocarcinoma in situ (AIS) with CT, even at follow-up, because they share many similar CT manifestations. While AAH is thought to be a precursor or even an early-stage lesion of lung adenocarcinoma, and the stepwise progression from AAH to AIS is thought to be reasonable. hTerefore, the hypothesis that the attenuation of GGO is increased gradually from AAH to AIS is proposed. hTe aim of this study was to distinguish AAH from AIS with CT attenuation in patients with pure GGO nodules. Methods:Between January 2010 and December 2012, the CT ifndings in terms of the greatest diameter and mean CT attenuation (HU) were reviewed and correlated with pathology in 56 patients with AAH (n=21) and non-mucinous AIS (n=38) by two independent observers. All the 59 lesions were pure GGO nodules with size of 2 cm or smaller. To determine variability of measuring CT attenuation, we calculated the 95%conifdence interval (CI) for the limits of agreement by using Bland-Altman analysis. Student t test was used to compare AAH and AIS in terms of diameter and CT attenuation. And receiver operating characteristic (ROC) curve was used to determine the optimal cut-off value of mean CT attenuation for differentiating AAH from AIS and obtain the diagnostic value. Two-tailed P value of less than 0.05 was considered to be signiifcant. Results:For the manually measured CT attenuation, the 95%CI for the limits of agreement was-40 HU, 50 HU for inter-observer variability. Although there was significant difference in nodule diameter between AAH and AIS (P=0.046), the overlap was considerable. hTe mean CT attenuation was (-718±53) HU (95%CI:-822,-604) for AAH, which was signiifcantly smaller than

  6. Standardised uptake values from PET/CT images: comparison with conventional attenuation-corrected PET

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    Souvatzoglou, M.; Ziegler, S.I.; Martinez, M.J.; Dzewas, G.; Schwaiger, M.; Bengel, F. [Nuklearmedizinische Klinik der Technischen Universitaet Muenchen, Munich (Germany); Busch, R. [Institut fuer Epidemiologie und Statistik der Technischen Universitaet Muenchen, Munich (Germany)

    2007-03-15

    In PET/CT, CT-derived attenuation factors may influence standardised uptake values (SUVs) in tumour lesions and organs when compared with stand-alone PET. Therefore, we compared PET/CT-derived SUVs intra-individually in various organs and tumour lesions with stand-alone PET-derived SUVs. Thirty-five patients with known or suspected cancer were prospectively included. Sixteen patients underwent FDG PET using an ECAT HR+scanner, and subsequently a second scan using a Biograph Sensation 16PET/CT scanner. Nineteen patients were scanned in the reverse order. All images were reconstructed with an iterative algorithm (OSEM). Suspected lesions were grouped as paradiaphragmatic versus distant from the diaphragm. Mean and maximum SUVs were also calculated for brain, lung, liver, spleen and vertebral bone. The attenuation coefficients ({mu} values) used for correction of emission data (bone, soft tissue, lung) in the two data sets were determined. A body phantom containing six hot spheres and one cold cylinder was measured using the same protocol as in patients. Forty-six lesions were identified. There was a significant correlation of maximum and mean SUVs derived from PET and PET/CT for 14 paradiaphragmatic lesions (r=0.97 respectively; p<0.001 respectively) and for 32 lesions located distant from the diaphragm (r=0.87 and r=0.89 respectively; p<0.001 respectively). No significant differences were observed in the SUVs calculated with PET and PET/CT in the lesions or in the organs. In the phantom, radioactivity concentration in spheres calculated from PET and from PET/CT correlated significantly (r=0.99; p<0.001). SUVs of cancer lesions and normal organs were comparable between PET and PET/CT, supporting the usefulness of PET/CT-derived SUVs for quantification of tumour metabolism. (orig.)

  7. Pitfalls in urinary stone identification using CT attenuation values: Are we getting the same information on different scanner models?

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    Grosjean, Romain, E-mail: r.grosjean@chu-nancy.fr [IADI Laboratory, INSERM-U947, Nancy-University, Allée du Morvan, 54500 Vandoeuvre-les-Nancy (France); Daudon, Michel, E-mail: michel.daudon@tnn.aphp.fr [IADI Laboratory, INSERM-U947, Nancy-University, Allée du Morvan, 54500 Vandoeuvre-les-Nancy (France); Chammas, Mario F., E-mail: mariochammas@usp.br [University of Sao Paulo – Division of Urology, Av. Dr. Enéas de Carvalho Aguiar, 255, 7" o Andar – s. 7123, São Paulo (Brazil); Claudon, Michel, E-mail: m.claudon@chu-nancy.fr [IADI Laboratory, INSERM-U947, Nancy-University, Allée du Morvan, 54500 Vandoeuvre-les-Nancy (France); Eschwege, Pascal, E-mail: peschwege@yahoo.com [Department of Urology, Brabois Hospital, University Hospital of Nancy, Allée du Morvan, 54511 Vandoeuvre-les-Nancy (France); Felblinger, Jacques, E-mail: j.felblinger@chu-nancy.fr [IADI Laboratory, INSERM-U947, Nancy-University, Allée du Morvan, 54500 Vandoeuvre-les-Nancy (France); Hubert, Jacques, E-mail: j.hubert@chu-nancy.fr [Department of Urology, Brabois Hospital, University Hospital of Nancy, Allée du Morvan, 54511 Vandoeuvre-les-Nancy (France)

    2013-08-15

    Introduction: Evaluate the capability of different Computed Tomography scanners to determine urinary stone compositions based on CT attenuation values and to evaluate potential differences between each model. Methods: 241 human urinary stones were obtained and their biochemical composition determined. Four different CT scanners (Siemens, Philips, GEMS and Toshiba) were evaluated. Mean CT-attenuation values and the standard deviation were recorded separately and compared with a t-paired test. Results: For all tested CT scanners, when the classification of the various types of stones was arranged according to the mean CT-attenuation values and to the confidence interval, large overlappings between stone types were highlighted. The t-paired test showed that most stone types could not be identified. Some types of stones presented mean CT attenuation values significantly different from one CT scanner to another. At 80 kV, the mean CT attenuation values obtained with the Toshiba Aquilion were significantly different from those obtained with the Siemens Sensation. On the other hand, mean values obtained with the Philips Brilliance were all significantly equal to those obtained with the Siemens Sensation and with the Toshiba Aquilion. At 120 kV mean CT attenuation values of uric acid, cystine and struvite stones obtained with the Philips model are significantly different from those obtained with the Siemens and the Toshiba but equal to those obtained with the GE 64. Conclusions: According to our study, there is a great variability when different brands and models of scanners are compared directly. Furthermore, the CT scan analysis and HU evaluation appears to gather insufficient information in order to characterize and identify the composition of renal stones.

  8. Helical CT evaluation of the chemical composition of urinary tract calculi with a discriminant analysis of CT-attenuation values and density

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    Bellin, Marie-France; Meric, Jean-Baptiste [AP-HP, Department of Radiology, Hopital Paul-Brousse, Villejuif Cedex (France); Renard-Penna, Raphaelle; Grenier, Philippe [AP-HP, Department of Radiology, Hopital Pitie-Salpetriere, Paris Cedex 13 (France); Conort, Pierre; Richard, Francois [AP-HP, Department of Urology, Hopital Pitie-Salpetriere, Paris Cedex 13 (France); Bissery, Anne; Mallet, Alain [AP-HP, Department of Biostatistics, Hopital Pitie-Salpetriere, Paris Cedex 13 (France); Daudon, Michel [AP-HP, Department of Biochemistry, Hopital Necker, Paris Cedex 15 (France)

    2004-11-01

    The aim of this study was to evaluate the efficacy of helical CT using a combination of CT-attenuation values and visual assessment of stone density as well as discriminant linear analysis to predict the chemical composition of urinary calculi. One hundred human urinary calculi were obtained from a stone-analysis laboratory and placed in 20 excised pig kidneys. They were scanned at 80, 120 and 140 kV with 3-mm collimation. Average, highest and lowest CT-attenuation values and CT variability were recorded. The internal calculus structure was assessed using a wide window setting, and visual assessment of stone density was recorded. A stepwise discriminant linear analysis was performed. The following three variables were discriminant: highest CT-attenuation value, visual density, and highest CT-attenuation value/area ratio, all at 80 kV. The probability of correctly classifying stone composition with these three variables was 0.64, ranging from 0.54 for mixed calculi to 0.69 for pure calculi. The probabilities of correctly classifying calculus composition were: 0.91 for calcium oxalate monohydrate and brushite, 0.89 for cystine, 0.85 for uric acid, 0.11 for calcium oxalate dihydrate, 0.10 for hydroxyapatite, and 0.07 for struvite calculi. When the first two ranks of highest probability for the accurate classification of each calculus type were taken into account, 81% of the calculi were correctly classified. Assessment at 80 kV of the highest CT-attenuation value, visual density and the highest CT-attenuation value/area ratio accurately predicts the chemical composition of 64-81% of urinary calculi. When the first two ranks of highest probability for the accurate classification of each calculus type were taken into account, all cystine, calcium oxalate monohydrate and brushite calculi were correctly classified. (orig.)

  9. A model for filtered backprojection reconstruction artifacts due to time-varying attenuation values in perfusion C-arm CT

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    Fieselmann, Andreas; Dennerlein, Frank; Deuerling-Zheng, Yu; Boese, Jan; Fahrig, Rebecca; Hornegger, Joachim

    2011-06-01

    Filtered backprojection is the basis for many CT reconstruction tasks. It assumes constant attenuation values of the object during the acquisition of the projection data. Reconstruction artifacts can arise if this assumption is violated. For example, contrast flow in perfusion imaging with C-arm CT systems, which have acquisition times of several seconds per C-arm rotation, can cause this violation. In this paper, we derived and validated a novel spatio-temporal model to describe these kinds of artifacts. The model separates the temporal dynamics due to contrast flow from the scan and reconstruction parameters. We introduced derivative-weighted point spread functions to describe the spatial spread of the artifacts. The model allows prediction of reconstruction artifacts for given temporal dynamics of the attenuation values. Furthermore, it can be used to systematically investigate the influence of different reconstruction parameters on the artifacts. We have shown that with optimized redundancy weighting function parameters the spatial spread of the artifacts around a typical arterial vessel can be reduced by about 70%. Finally, an inversion of our model could be used as the basis for novel dynamic reconstruction algorithms that further minimize these artifacts.

  10. A model for filtered backprojection reconstruction artifacts due to time-varying attenuation values in perfusion C-arm CT

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    Fieselmann, Andreas; Hornegger, Joachim [Department of Computer Science, Pattern Recognition Lab, Friedrich-Alexander University of Erlangen-Nuremberg, Martensstr. 3, 91058 Erlangen (Germany); Dennerlein, Frank; Deuerling-Zheng, Yu; Boese, Jan [Siemens AG, Healthcare Sector, Angiography and Interventional X-Ray Systems, Siemensstr. 1, 91301 Forchheim (Germany); Fahrig, Rebecca, E-mail: andreas.fieselmann@informatik.uni-erlangen.de [Department of Radiology, Lucas MRS Center, Stanford University, 1201 Welch Road, Palo Alto, CA 94305 (United States)

    2011-06-21

    Filtered backprojection is the basis for many CT reconstruction tasks. It assumes constant attenuation values of the object during the acquisition of the projection data. Reconstruction artifacts can arise if this assumption is violated. For example, contrast flow in perfusion imaging with C-arm CT systems, which have acquisition times of several seconds per C-arm rotation, can cause this violation. In this paper, we derived and validated a novel spatio-temporal model to describe these kinds of artifacts. The model separates the temporal dynamics due to contrast flow from the scan and reconstruction parameters. We introduced derivative-weighted point spread functions to describe the spatial spread of the artifacts. The model allows prediction of reconstruction artifacts for given temporal dynamics of the attenuation values. Furthermore, it can be used to systematically investigate the influence of different reconstruction parameters on the artifacts. We have shown that with optimized redundancy weighting function parameters the spatial spread of the artifacts around a typical arterial vessel can be reduced by about 70%. Finally, an inversion of our model could be used as the basis for novel dynamic reconstruction algorithms that further minimize these artifacts.

  11. A retrospective evaluation of Randall's plaque theory of nephrolithiasis with CT attenuation values

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    Bhuskute, Nikhil M. [Leeds Teaching Hospitals, Leeds, Radiology Academy, Leeds General Infirmary, Great George Street, Leeds LS1 3EX (United Kingdom)], E-mail: nbhuskute@googlemail.com; Yap, Wan Wan [Leeds Teaching Hospitals, Leeds, Radiology Academy, Leeds General Infirmary, Great George Street, Leeds LS1 3EX (United Kingdom)], E-mail: wanwanyap@gmail.com; Wah, Tze M. [St. James' s University Hospital, Leeds LS9 7TF (United Kingdom)], E-mail: Tze.Wah@leedsth.nhs.uk

    2009-12-15

    Purpose: We examined the computed tomography attenuation values (HU) of renal papillae in stone formers (SF) to determine whether nephrolithiasis is associated with radiographic changes in renal papillae to investigate the Randall's plaque theory. Materials and methods: Two observers independently and retrospectively recorded the HU of the renal medullae and cortex in 90 patients with a unilateral single calculus within kidney or ureter, and in 104 cases in control group (CG) matched for age and renal functions. Results: The patient ages were similar in the stone former and control groups. However, the male-female ratio was significantly greater in the SF group (68:22) than in the CG (42:62, P < 0.0001). Left-right ratio in SF group was 50:40. The inter-rater agreement was {kappa} = 0.53 (95% CI: 0.42, 0.64). Mean HU of all papillae of affected side in stone-formers (ASSF) was significantly greater than that in CG (39.6 versus 29.6, P < 0.0001). When comparing affected and non-affected sides within the SF group, there was no significant difference (39.6 versus 38.4, P = 0.16). The receiver operating characteristic (ROC) analysis showed area under curve = 0.94 with optimal cut-off at 34 HU. At this point the specificity, sensitivity, PPV and NPV were 90%, 90%, 33% and 99%, respectively. Conclusion: HU of the renal papilla is significantly increased in SF in the affected and the non-affected kidneys when compared to the CG. This finding may form one of the risk indicators to determine the future follow up and clinical management for the potential SF.

  12. Comparison of iodinated contrast media for the assessment of atherosclerotic plaque attenuation values by CT coronary angiography: Observations in an ex vivo model

    NARCIS (Netherlands)

    L. la Grutta (Ludovico); M. Galia (Massimo); G. Gentile; G. Lo Re (G.); E. Grassedonio (Emanuele); F. Coppolino; E. Maffei (Erica); E. Maresi (E.); A. Lo Casto (A.); F. Cademartiri (Filippo); M. Midiri (Massimo)

    2013-01-01

    textabstractObjective: To compare the influence of different iodinated contrast media with several dilutions on plaque attenuation in an ex vivo coronary model studied by multislice CT coronary angiography. Methods: In six ex vivo left anterior descending coronary arteries immersed in oil, CT (slice

  13. Additional Value of Transluminal Attenuation Gradient in CT Angiography to Predict Hemodynamic Significance of Coronary Artery Stenosis

    Science.gov (United States)

    Stuijfzand, Wynand J.; Danad, Ibrahim; Raijmakers, Pieter G.; Marcu, C. Bogdan; Heymans, Martijn W.; van Kuijk, Cornelis C.; van Rossum, Albert C.; Nieman, Koen; Min, James K.; Leipsic, Jonathon; van Royen, Niels; Knaapen, Paul

    2015-01-01

    OBJECTIVES The current study evaluates the incremental value of transluminal attenuation gradient (TAG), TAG with corrected contrast opacification (CCO), and TAG with exclusion of calcified coronary segments (ExC) over coronary computed tomography angiogram (CTA) alone using fractional flow reserve (FFR) as the gold standard. BACKGROUND TAG is defined as the contrast opacification gradient along the length of a coronary artery on a coronary CTA. Preliminary data suggest that TAG provides additional functional information. Interpretation of TAG is hampered by multiple heartbeat acquisition algorithms and coronary calcifications. Two correction models have been proposed based on either dephasing of contrast delivery by relating coronary density to corresponding descending aortic opacification (TAG-CCO) or excluding calcified coronary segments (TAG-ExC). METHODS Eighty-five patients with intermediate probability of coronary artery disease were prospectively included. All patients underwent step-and-shoot 256-slice coronary CTA. TAG, TAG-CCO, and TAG-ExC analyses were performed followed by invasive coronary angiography in conjunction with FFR measurements of all major coronary branches. RESULTS Thirty-four patients (40%) were diagnosed with hemodynamically-significant coronary artery disease (i.e., FFR ≤0.80). On a per-vessel basis (n = 253), 59 lesions (23%) were graded as hemodynamically significant, and the diagnostic accuracy of coronary CTA (diameter stenosis ≥50%) was 95%, 75%, 98%, and 54% for sensitivity, specificity, negative predictive value, and positive predictive value, respectively. TAG and TAG-ExC did not discriminate between vessels with or without hemodynamically significant lesions (−13.5 ± 17.1 HU [Hounsfield units] × 10 mm−1 vs. −11.6 ± 13.3 HU × 10 mm−1, p = 0.36; and 13.1 ± 15.9 HU × 10 mm−1 vs. −11.4 ± 11.7 HU × 10 mm−1, p = 0.77, respectively). TAG-CCO was lower in vessels with a hemodynamically-significant lesion (−0

  14. CT attenuation of colorectal polypoid lesions: evaluation of contrast enhancement in CT colonography

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    Oto, Aytekin [Department of Radiology, Hacettepe University School of Medicine, Ankara (Turkey); Department of Radiology, University of Texas Medical Branch at Galveston, 301 University Boulevard, 77555-0709, Galveston, TX (United States); Gelebek, Veli; Oguz, Berna Sayan; Deger, Ahmet; Akhan, Okan; Besim, Aytekin [Department of Radiology, Hacettepe University School of Medicine, Ankara (Turkey); Sivri, Buelent [Department of Gastroenterology, Hacettepe University School of Medicine, Ankara (Turkey)

    2003-07-01

    The aim of this study was to calculate pre- and postcontrast CT attenuation values of benign colorectal polyp and carcinoma lesions detected by virtual colonoscopy, and to investigate whether contrast enhancement of these lesions can be potentially used for differentiation from residual fluid in the colon. Fifteen benign polyps and 21 colorectal carcinoma lesions detected by virtual colonoscopy in 18 patients were included in our study. All of the polyps and carcinoma lesions were confirmed by colonoscopic biopsy. Measurement of CT attenuation values was performed in precontrast (supine) and postcontrast (prone) scans for each polyp and carcinoma. The CT attenuation values of residual fluid in the colon was also measured from the same location before and after intravenous contrast administration. On unenhanced CT scan mean attenuation values of benign polyps and colorectal carcinomas were 32.4 and 42.6 HU, respectively. Following contrast enhancement, mean attenuation value increased to 78.9 HU for polyps and 90.7 HU for carcinomas. Increase in the CT attenuation values of these lesions was significant (p <0.0001). Mean CT attenuation value of residual fluid before and after administration of IV contrast were 14.6 and 13.8 HU, respectively. The difference between CT attenuation value of residual fluid in the colon before and after contrast material was not significant (p =0.29). Colorectal benign polyps and carcinomas demonstrate significant enhancement following contrast administration and use of intravenous contrast material during virtual colonoscopy may help in some cases in differentiating these solid lesions from residual colonic fluid that does not enhance. (orig.)

  15. The clinical application of the CT attenuation value in the differential diagnosis of common adrenal tumors%平扫CT值在常见肾上腺肿瘤鉴别诊断中的应用价值

    Institute of Scientific and Technical Information of China (English)

    陈雅童; 赵佳晖; 王永兴; 韦能宝; 姜永光

    2012-01-01

    Objective: To evaluate application of the CT attenuation value in the diagnosis of common adrenal tumors and to define the proper threshold value for differentiating adrenal adenoma and non-adenoma according to CT attenuation value combined with tumor size. Method: A retrospective analysis of 209 cases of adrenal tumors (221 lesions),constituted by 137 adenomas and 84 non-adenomas which were confirmed by pathological results, was carried out. Tumor size and CT attenuation value were measured and the sensitivity,specificity,accuracy,positive predictive value and negative predictive value at different thresholds for differentiating the adrenal adenoma and non-adenoma were calculated respectively. Result: The mean CT attenuation value of 137 adenomas was 12 — 59 (13. 19 ± 12. 84)HU,tumor size 0. 3 — 7. 3cm,including 88 no-function adenomas,the CT attenuation value —12 -59 (15.04 ± 13. 01)HU;43 aldosterone adenomas,the CT attenuation value -8-42 (10.19 ± 12. 26)HU;6 cortisol adenomas, the CT attenuation value —4. 6 — 18 (7. 58 ± 10. 16)HU. The mean CT attenuation value of 84 non-adenomas was 15 — 69 (38. 33 ± 10. 08)HU,tumor size 1. 5 —11. 6 cm,including 43 pheochromocytomas,the CT attenuation value 15—69 (38. 67 ± 11. 05) HU; 5 Ganglioneuroma tumors,the CT attenuation value 18 — 39 (29. 60 ± 8. 65)HU;28 cortical carcinomas,the CT attenuation value 26 — 58 (38. 96 ± 8. 84)HU;8 metastases, the CT attenuation value 28 — 54 (39. 75 ± 8. 24)HU. There was significant difference in the mean CT attenuation value between adenomas and non adenoma(t = — 15. 281, P = 0. 000). The sensitivity,specificity,accuracy,positive predictive value and negative predictive value for making the diagnosis of adenoma were 73. 7%, 100%, 83. 7% , 100% ,70%restectively according to the CT attenuation value was less than 25 HU and the tumor size less than 4 cm. Conclusion: The application of CT attenuation value is valuable for the differential diagnosis of adrenal

  16. Derivation of attenuation map for attenuation correction of PET data in the presence of nanoparticulate contrast agents using spectral CT imaging

    NARCIS (Netherlands)

    Ghadiri, Hossein; Shiran, Mohammad Bagher; Soltanian-Zadeh, Hamid; Rahmim, Arman; Zaidi, Habib; Ay, Mohammad Reza

    2014-01-01

    Uptake value in quantitative PET imaging is biased due to the presence of CT contrast agents when using CT-based attenuation correction. Our aim was to examine spectral CT imaging to suppress inaccuracy of 511 keV attenuation map in the presence of multiple nanoparticulate contrast agents. Using a s

  17. Attenuation correction of myocardial SPECT images with X-ray CT. Effects of registration errors between X-ray CT and SPECT

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    Takahashi, Yasuyuki; Murase, Kenya [Osaka Univ., Suita (Japan). Graduate School of Medicine; Higashino, Hiroshi [Ehime Prefectural Imabari Hospital (Japan); Mochizuki, Teruhito [Ehime Univ., Matsuyama (Japan). School of Medicine; Motomura, Nobutoku [Toshiba Corp., Otawara, Tochigi (Japan). Medical Engineering Lab.

    2002-09-01

    Attenuation correction with an X-ray CT image is a new method to correct attenuation on SPECT imaging, but the effect of the registration errors between CT and SPECT images is unclear. In this study, we investigated the effects of the registration errors on myocardial SPECT, analyzing data from a phantom and a human volunteer. Registerion (fusion) of the X-ray CT and SPECT images was done with standard packaged software in three dimensional fashion, by using linked transaxial, coronal and sagittal images. In the phantom study, and X-ray CT image was shifted 1 to 3 pixels on the x, y and z axes, and rotated 6 degrees clockwise. Attenuation correction maps generated from each misaligned X-ray CT image were used to reconstruct misaligned SPECT images of the phantom filled with {sup 201}Tl. In a human volunteer, X-ray CT was acquired in different conditions (during inspiration vs. expiration). CT values were transferred to an attenuation constant by using straight lines; an attenuation constant of 0/cm in the air (CT value=-1,000 HU) and that of 0.150/cm in water (CT value=0 HU). For comparison, attenuation correction with transmission CT (TCT) data and an external {gamma}-ray source ({sup 99m}Tc) was also applied to reconstruct SPECT images. Simulated breast attenuation with a breast attachment, and inferior wall attenuation were properly corrected by means of the attenuation correction map generated from X-ray CT. As pixel shift increased, deviation of the SPECT images increased in misaligned images in the phantom study. In the human study, SPECT images were affected by the scan conditions of the X-ray CT. Attenuation correction of myocardial SPECT with an X-ray CT image is a simple and potentially beneficial method for clinical use, but accurate registration of the X-ray CT to SPECT image is essential for satisfactory attenuation correction. (author)

  18. Periportal low-attenuation: a CT sign of lymphatic obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Hoon; Kim, Chong Soo; Yang, Doo Hyun; Lee, Sang Yong; Lee, Young Whan; Chung, Gyung Ho; Han, Young Min; Sohn, Myung Hee; Choi, Ki Chul [Chonbuk National University College of Medicine, Jeonju (Korea, Republic of)

    1995-07-15

    Periportal low attenuation, defined as a low attenuation rim around the portal vein and its branches which is seen on contrast material-enhanced CT scans, has been described in a variety of conditions. We tried to document that lymphatic obstruction is one of the major cause of periportal low attenuation. We retrospectively analyzed 57 cases of periportal low attenuation of abdominal CT scans and also reviewed the surgical records in 32 cases. Lymph node enlargement in the hepatoduodenal ligament which is a main lymphatic channel from the liver were analyzed the calculated the ratio of the transeverse diameter between the inferior vena cava and the aorta at the level of right adrenal gland. After complete surgical interruption of the lymphatic drainage from the liver in a dog, follow up CT scans were obtained and correlated with pathologic findings. Fifty patients (88%) had underlying disease which could cause impairment of lymphatic drainage. Periportal low attenuation was identified in several clinical conditions, including surgical lymph node dissection, lymphadenopathy in the hepatoduodenal ligament, blunt trauma. In animal model, CT scan showed prominent periportal low attenuation at 5 days after surgery. Histologic examination revealed numerous dilated lymphatic vessels and a marked lymphedema in the connective tissues surrounding the portal vein and its major branches. One of the major cause of periportal low attenuation was impaired lymphatic drainage and periportal low attenuation corresponding to the numerous dilated lymphatic vessels and a marked lymphedema in the connective tissues surrounding the portal vein and its major branches.

  19. Limits of Ultra-Low Dose CT Attenuation Correction for PET/CT.

    Science.gov (United States)

    Xia, Ting; Alessio, Adam M; Kinahan, Paul E

    2010-01-29

    We present an analysis of the effects of ultra-low dose X-ray computerized tomography (CT) based attenuation correction for positron emission tomography (PET). By ultra low dose we mean less than approximately 5 mAs or 0.5 mSv total effective whole body dose. The motivation is the increased interest in using respiratory motion information acquired during the CT scan for both phase-matched CT-based attenuation correction and for motion estimation. Since longer duration CT scans are desired, radiation dose to the patient can be a limiting factor. In this study we evaluate the impact of reducing photon flux rates in the CT data on the reconstructed PET image by using the CATSIM simulation tool for the CT component and the ASIM simulation tool for the PET component. The CT simulation includes effects of the x-ray tube spectra, beam conditioning, bowtie filter, detector noise, and bean hardening correction. The PET simulation includes the effect of attenuation and photon counting. Noise and bias in the PET image were evaluated from multiple realizations of test objects. We show that techniques can be used to significantly reduce the mAs needed for CT based attenuation correction if the CT is not used for diagnostic purposes. The limiting factor, however, is not the noise in the CT image but rather the bias introduced by CT sinogram elements with no detected flux. These results constrain the methods that can be used to lower CT dose in a manner suitable for attenuation correction of PET data. We conclude that ultra-low-dose CT for attenuation correction of PET data is feasible with current PET/CT scanners.

  20. Impact of metallic dental implants on CT-based attenuation correction in a combined PET/CT scanner

    Energy Technology Data Exchange (ETDEWEB)

    Kamel, Ehab M.; Burger, Cyrill; Buck, Alfred; Schulthess, Gustav K. von; Goerres, Gerhard W. [Division of Nuclear Medicine, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland)

    2003-04-01

    Our objective was to study the effect of metal-induced artifacts on the accuracy of the CT-based anatomic map as a prerequisite for attenuation correction of the positron emission tomography (PET) emission data. Twenty-seven oncology patients with dental metalwork were enrolled in the present study. Data acquisition was performed on a PET/CT in-line system (Discovery LS, GE Medical Systems, Milwaukee, Wis.). Attenuation correction of emission data was done twice, using an 80-mA CT scan (PET{sub CT80}) and a {sup 68}Ge transmission scan (PET{sub 68Ge}). Average count in kBq/cc was measured in regions with and without artifacts and compared for PET{sub CT80} and PET{sub 68Ge}. Data analysis of region of interests (ROIs) revealed that the ratio (ROIs PET{sub CT80}/ROIs PET{sub 68Ge}) and the difference (ROIs PET{sub CT80} minus ROIs PET{sub 68Ge}) had a higher mean of values in regions with artifacts than in regions without artifacts (1.2{+-}0.17 vs 1.06{+-}0.06 and 0.68{+-}0.67 vs 0.15{+-}0.17 kBq/cc, respectively). For most of the studied artifactual ROIs, the PET{sub CT80} values were higher than those of the PET{sub 68Ge}. Attenuation correction of PET emission data using an artifactual CT map yields false values in regions nearby artifacts caused by dental metalwork. This may falsely estimate PET quantitative studies and may disturb the visual interpretation of PET scan. (orig.)

  1. Fat Attenuation at CT in Anorexia Nervosa.

    Science.gov (United States)

    Gill, Corey M; Torriani, Martin; Murphy, Rachel; Harris, Tamara B; Miller, Karen K; Klibanski, Anne; Bredella, Miriam A

    2016-04-01

    To investigate the composition, cross-sectional area (CSA), and hormonal correlates of different fat depots in women with anorexia nervosa (AN) and control subjects with normal weights to find out whether patients with AN have lower fat CSA but higher attenuation than did control subjects and whether these changes may be mediated by gonadal steroids, cortisol, and thyroid hormones. This study was institutional review board approved and HIPAA compliant. Written informed consent was obtained. Forty premenopausal women with AN and 40 normal-weight women of comparable age (mean age ± standard deviation, 26 years ± 5) were studied. All individuals underwent computed tomography of the abdomen and thigh with a calibration phantom. Abdominal subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), thigh SAT, and thigh intermuscular adipose tissue CSA and attenuation were quantified. Serum estradiol, thyroid hormones, and urinary free cortisol levels were assessed. Variables were compared by using analysis of variance. Associations were examined by using linear regression analysis. Women with AN had higher fat attenuation than did control subjects (-100.1 to -46.7 HU vs -117.6 to -61.8 HU, P fat CSA (2.0-62.8 cm(2) vs 5.5-185.9 cm(2), P fat attenuation (r = -0.34 to -0.61, P = .03 to fat CSA of all compartments (r = 0.42-0.64, P = .007 to fat composition, with higher fat attenuation than that of control subjects, as well as low fat mass. VAT attenuation but not CSA is inversely associated with lowest prior lifetime body mass index, suggesting that fat attenuation may serve as a biomarker of prior and current disease status in AN.

  2. The value of CT in Differentiation of Adrenal Adenomas from Malignant Tumors

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To evaluate the diagnostic efficacy of CT indifferentiating adrenal adenomas from malignant tumors. Methods: 124 patients with 147 adrenal adenomas and malignant tumors were analyzed. Tumor size, margin, internal structure and the relation of the tumor to the adrenal gland were investigated with CT. Both precontrast and postcontrast CT attenuation values of the tumor were measured and the enhanced degree was calculated respectively. CT pixel mapping of the tumor was done in 20 patients. Results were analyzed by using ROC curve. Results: The area under the ROC curve for precontrast CT attenuation values (0.91± 0.05) was significantly larger than that for postcontrast CT attenuation values (0.83± 0.04), enhanced degree (0.74± 0.08) or tumor sizes (0.82± 0.04). With a threshold of tumor size 3.0 cm, homogenous density, precontrast CT attenuation value 20 HU, postcontrast CT attenuation value 35 HU or enhanced degree 20 HU, the sensitive for characterizing adenomas were 86%, 85%, 88%, 76% and 74%, and the specificity were 73%, 72%, 91%, 78% and 61% respectively. Connection with normal adrenal gland (68%), precontrast CT attenuation value<0 HU (17%), and area of slightly negative CT attenuation value on CT pixel mapping were only seen in adrenal adenomas, whereas poorly defined margin and/or invasion of surrounding structures (30%), irregular thick rim enhancement (22%) were characteristic of malignant tumors. The overall correspondence rate with final diagnosis was 92.7% in our group. Conclusion: Most of the adrenal adenomas and malignant tumors can be distinguished by comprehensive analysis of CT features.

  3. Attenuation correction in cardiac PET/CT with three different CT protocols: a comparison with conventional PET

    Energy Technology Data Exchange (ETDEWEB)

    Souvatzoglou, Michael [Nuklearmedizinische Klinik und Poliklinik der Technischen Universitaet Muenchen, Munich (Germany); Nuklearmedizinische Klinik der Technischen Universitaet Muenchen, Munich (Germany); Bengel, Frank; Kruschke, Coletta; Fernolendt, Helga; Lee, Denise; Schwaiger, Markus; Nekolla, Stephan G. [Nuklearmedizinische Klinik und Poliklinik der Technischen Universitaet Muenchen, Munich (Germany); Busch, Raymonde [Institut fuer Statistik und Epidemiologie der Technischen Universitaet Muenchen, Munich (Germany)

    2007-12-15

    CT-based attenuation correction may influence cardiac PET owing to its higher susceptibility to misalignment compared with conventional {sup 68}Ge transmission scans. The aims of this study were to evaluate whether CT attenuation correction leads to changes in tracer distribution compared with conventional cardiac PET and to determine a suitable CT protocol. A total of 27 patients underwent PET/CT and subsequently a PET scan. Twenty patients received a low-dose CT (LDCT group; 120 kV, 26 mA, 8-s scan time), seven patients a slow CT (SCT group; 120 kV, 99 mA, 46-s scan time) and ten patients an ultra-low-dose CT (ULDCT group; 80 kV, 13 mA, 5-s scan time) as the transmission scan in PET/CT. Polar maps were divided into 17 segments and regression analysis was computed in every scan pair (CT attenuation corrected-{sup 68}Ge attenuation corrected). Correlation coefficient (r), the slope (s) and the offset (os) of the regression line were determined. Visual assessment of misalignment between the transmission and emission data was performed. The effective dose of the different transmission scans was calculated. Overall, there was a moderate correlation between the mean values measured in all segments on PET/CT and on PET when using LDCT (r=0.78, p<0.0001), SCT (r=0.79, p<0.0001) and ULDCT (r=0.82, p<0.0001). No differences were observed when comparing the scores assigned in the visual misalignment assessment in the three groups (p=0.12). The differences between the results from the regression analysis observed in the respective groups were not statistically significant (Kruskal-Wallis p=0.11 for r, p=0.67 for s and p=0.27 for os). The effective dose was lowest for the ULDCT. Our study shows that CT-based attenuation correction is feasible for cardiac PET imaging. The results indicate that ultra-low-dose CT is the preferable choice for transmission scanning. (orig.)

  4. The low attenuation area on dual-energy perfusion CT: Correlation with the pulmonary function tests and quantitative CT measurements

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Munemasa, E-mail: radokada@yamaguchi-u.ac.jp [Department of Radiology, Yamaguchi University Graduate School of Medicine (Japan); Kunihiro, Yoshie; Nakashima, Yoshiteru; Matsunaga, Naofumi [Department of Radiology, Yamaguchi University Graduate School of Medicine (Japan); Sano, Yuichi; Yuasa, Yuuki; Narazaki, Akiko; Kudomi, Shohei; Koike, Masahiro [Department of Radiology, Yamaguchi University Hospital (Japan); Kido, Shoji [Computer-aided Diagnosis and Biomedical Imaging Research Biomedical Engineering, Applied Medical Engineering Science Graduate School of Medicine, Yamaguchi University (Japan)

    2012-10-15

    Purpose: To retrospectively investigate the distribution of the low attenuation area (LAA) on dual energy perfusion CT (DEpCT) in comparison with the results of pulmonary function tests (PFTs) and quantitative CT measurements. Materials and methods: Twenty-eight patients (15 male and 13 female; mean age: 62.21 years) underwent DEpCT and PFTs within a 1-month interval. The ranges of the LAA on DEpCT were classified into six groups with attenuation values of 0–3, 0–5, 0–8, 0–10, 0–13 and 0–15 HU and the ratios of LAA in each group were compared with the percentage of forced expiratory volume in the 1st second (%FEV{sub 1.0}), FEV{sub 1.0}/forced vital capacity (FEV{sub 1.0}/FVC) and the relative area of the lung with attenuation coefficients lower than −950 HU (RA{sub −950}). Results: The LAAs on the DEpCT images were significantly correlated with the RA{sub −950}, %FEV{sub 1.0} and FEV{sub 1.0}/FVC, and the regression analysis showed that the best values of LAA on DEpCT were 0–10 HU with RA{sub −950} (r = 0.63), 0–8 HU with %FEV{sub 1.0} (r = −0.52) and 0–8 HU with FEV{sub 1.0}/FVC (r = −0.61) per patient. Conclusion: The iodine disturbance on DEpCT had a moderate correlation with the results of the PFTs and RA{sub −950}, but further examination would be needed for evaluation of iodine distribution.

  5. Ultra-low dose CT attenuation correction for PET/CT

    Science.gov (United States)

    Xia, Ting; Alessio, Adam M.; De Man, Bruno; Manjeshwar, Ravindra; Asma, Evren; Kinahan, Paul E.

    2012-01-01

    A challenge for positron emission tomography/computed tomography (PET/CT) quantitation is patient respiratory motion, which can cause an underestimation of lesion activity uptake and an overestimation of lesion volume. Several respiratory motion correction methods benefit from longer duration CT scans that are phase matched with PET scans. However, even with the currently available, lowest dose CT techniques, extended duration cine CT scans impart a substantially high radiation dose. This study evaluates methods designed to reduce CT radiation dose in PET/CT scanning. We investigated selected combinations of dose reduced acquisition and noise suppression methods that take advantage of the reduced requirement of CT for PET attenuation correction (AC). These include reducing CT tube current, optimizing CT tube voltage, adding filtration, CT sinogram smoothing and clipping. We explored the impact of these methods on PET quantitation via simulations on different digital phantoms. CT tube current can be reduced much lower for AC than that in low dose CT protocols. Spectra that are higher energy and narrower are generally more dose efficient with respect to PET image quality. Sinogram smoothing could be used to compensate for the increased noise and artifacts at radiation dose reduced CT images, which allows for a further reduction of CT dose with no penalty for PET image quantitation. When CT is not used for diagnostic and anatomical localization purposes, we showed that ultra-low dose CT for PET/CT is feasible. The significant dose reduction strategies proposed here could enable respiratory motion compensation methods that require extended duration CT scans and reduce radiation exposure in general for all PET/CT imaging.

  6. Attenuation correction effects on SPECT/CT procedures: phantoms studies.

    Science.gov (United States)

    Oliveira, M L; Seren, M E G; Rocha, F C; Brunetto, S Q; Ramos, C D; Button, V L S N

    2013-01-01

    Attenuation correction is widely used in SPECT/CT (Single Photon Emission Computed Tomography) procedures, especially for imaging of the thorax region. Different compensation methods have been developed and introduced into clinical practice. Most of them use attenuation maps obtained using transmission scanning systems. However, this gives extra dose of radiation to the patient. The purpose of this study was to identify when attenuation correction is really important during SPECT/CT procedures.For this purpose, we used Jaszczak phantom and phantom with three line sources, filled with technetium ((99m)-Tc), with scattering materials, like air, water and acrylic, in different detectors configurations. In all images acquired were applied analytic and iterative reconstruction algorithms; the last one with or without attenuation correction. We analyzed parameters such as eccentricity, contrast and spatial resolution in the images.The best reconstruction algorithm on average was iterative, for images with 128 × 128 and 64 × 64 matrixes. The analytical algorithm was effective only to improve eccentricity in 64 × 64 matrix and matrix in contrast 128 × 128 with low statistics. Turning to the clinical routine examinations, on average, for 128 × 128 matrix and low statistics counting, the best algorithm was the iterative, without attenuation correction,improving in 150% the three parameters analyzed and, for the same matrix size, but with high statistical counting, iterative algorithm with attenuation correction was 25% better than that without correction. We can conclude that using the iterative algorithm with attenuation correction in the water, and its extra dose given, is not justified for the procedures of low statistic counting, being relevant only if the intention is to prioritize contrast in acquisitions with high statistic counting.

  7. Clinical values of CT and dynamic CT in brain infarction

    Energy Technology Data Exchange (ETDEWEB)

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

    1985-04-15

    -and postcontrast CT scan had a marked difference in CT (HU) on absolute scale graph of dynamic CT, so diagnosis of lacunar infarction could be made easily. 7. The clinical values of dynamic CT consist in not only diagnosis of lacunar infarction but also evaluation of effectiveness of medical or surgical treatment.

  8. Photon counting spectroscopic CT with dynamic beam attenuator

    CERN Document Server

    Atak, Haluk

    2016-01-01

    Purpose: Photon counting (PC) computed tomography (CT) can provide material selective CT imaging at lowest patient dose but it suffers from suboptimal count rate. A dynamic beam attenuator (DBA) can help with count rate by modulating x-ray beam intensity such that the low attenuating areas of the patient receive lower exposure, and detector behind these areas is not overexposed. However, DBA may harden the beam and cause artifacts and errors. This work investigates positive and negative effects of using DBA in PCCT. Methods: A simple PCCT with single energy bin, spectroscopic PCCT with 2 and 5 energy bins, and conventional energy integrating CT with and without DBA were simulated and investigated using 120kVp tube voltage and 14mGy air dose. The DBAs were modeled as made from soft tissue (ST) equivalent material, iron (Fe), and holmium (Ho) K-edge material. A cylindrical CT phantom and chest phantom with iodine and CaCO3 contrast elements were used. Image artifacts and quantification errors in general and mat...

  9. CT-Based Attenuation Correction in I-123-Ioflupane SPECT

    Science.gov (United States)

    Lange, Catharina; Seese, Anita; Schwarzenböck, Sarah; Steinhoff, Karen; Umland-Seidler, Bert; Krause, Bernd J.; Brenner, Winfried; Sabri, Osama

    2014-01-01

    Purpose Attenuation correction (AC) based on low-dose computed tomography (CT) could be more accurate in brain single-photon emission computed tomography (SPECT) than the widely used Chang method, and, therefore, has the potential to improve both semi-quantitative analysis and visual image interpretation. The present study evaluated CT-based AC for dopamine transporter SPECT with I-123-ioflupane. Materials and methods Sixty-two consecutive patients in whom I-123-ioflupane SPECT including low-dose CT had been performed were recruited retrospectively at 3 centres. For each patient, 3 different SPECT images were reconstructed: without AC, with Chang AC and with CT-based AC. Distribution volume ratio (DVR) images were obtained by scaling voxel intensities using the whole brain without striata as reference. For assessing the impact of AC on semi-quantitative analysis, specific-to-background ratios (SBR) in caudate and putamen were obtained by fully automated SPM8-based region of interest (ROI) analysis and tested for their diagnostic power using receiver-operator-characteristic (ROC) analysis. For assessing the impact of AC on visual image reading, screenshots of stereotactically normalized DVR images presented in randomized order were interpreted independently by two raters at each centre. Results CT-based AC resulted in intermediate SBRs about half way between no AC and Chang. Maximum area under the ROC curve was achieved by the putamen SBR, with negligible impact of AC (0.924, 0.935 and 0.938 for no, CT-based and Chang AC). Diagnostic accuracy of visual interpretation also did not depend on AC. Conclusions The impact of CT-based versus Chang AC on the interpretation of I-123-ioflupane SPECT is negligible. Therefore, CT-based AC cannot be recommended for routine use in clinical patient care, not least because of the additional radiation exposure. PMID:25268228

  10. CT-based attenuation correction in I-123-ioflupane SPECT.

    Directory of Open Access Journals (Sweden)

    Catharina Lange

    Full Text Available PURPOSE: Attenuation correction (AC based on low-dose computed tomography (CT could be more accurate in brain single-photon emission computed tomography (SPECT than the widely used Chang method, and, therefore, has the potential to improve both semi-quantitative analysis and visual image interpretation. The present study evaluated CT-based AC for dopamine transporter SPECT with I-123-ioflupane. MATERIALS AND METHODS: Sixty-two consecutive patients in whom I-123-ioflupane SPECT including low-dose CT had been performed were recruited retrospectively at 3 centres. For each patient, 3 different SPECT images were reconstructed: without AC, with Chang AC and with CT-based AC. Distribution volume ratio (DVR images were obtained by scaling voxel intensities using the whole brain without striata as reference. For assessing the impact of AC on semi-quantitative analysis, specific-to-background ratios (SBR in caudate and putamen were obtained by fully automated SPM8-based region of interest (ROI analysis and tested for their diagnostic power using receiver-operator-characteristic (ROC analysis. For assessing the impact of AC on visual image reading, screenshots of stereotactically normalized DVR images presented in randomized order were interpreted independently by two raters at each centre. RESULTS: CT-based AC resulted in intermediate SBRs about half way between no AC and Chang. Maximum area under the ROC curve was achieved by the putamen SBR, with negligible impact of AC (0.924, 0.935 and 0.938 for no, CT-based and Chang AC. Diagnostic accuracy of visual interpretation also did not depend on AC. CONCLUSIONS: The impact of CT-based versus Chang AC on the interpretation of I-123-ioflupane SPECT is negligible. Therefore, CT-based AC cannot be recommended for routine use in clinical patient care, not least because of the additional radiation exposure.

  11. Attenuation-based characterization of coronary atherosclerotic plaque: Comparison of dual source and dual energy CT with single-source CT and histopathology

    Energy Technology Data Exchange (ETDEWEB)

    Henzler, Thomas, E-mail: Thomas.Henzler@umm.de [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany); Porubsky, Stefan [Department of Pathology, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany); Kayed, Hany [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany); Harder, Nils [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany); Department of Pathology, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany); Krissak, U. Radko; Meyer, Mathias [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany); Sueselbeck, Tim [1st Department of Medicine University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany); Marx, Alexander [Department of Pathology, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany); Michaely, Henrik [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany); Schoepf, U. Joseph [Department of Radiology and Radiological Science, Medical University of South Carolina, 169 Ashley Avenue, Charleston (United States)

    2011-10-15

    Objective: To compare different CT acquisition techniques regarding for attenuation-based characterization of coronary atherosclerotic plaques using histopathology as the standard of reference. Materials and methods: In a post mortem study 17 human hearts were studied with dual-source CT (DSCT) and dual energy CT (DECT) mode on a DSCT as well as with 16-slice single-source CT (SSCT). At autopsy, atherosclerotic lesions were cut at 5 {mu}m sections. Histopathologic classification of the plaques according to the American Heart Association (AHA) criteria was performed by two pathologists. Attenuation values of all plaques were measured in DSCT, DECT and SSCT studies, respectively and classified based on attenuation according to modified AHA criteria. Results: 58 coronary plaques were identified at autopsy. Regardless of the CT technique only 52/58 plaques were found at CT (sensitivity = 89.6%). There was no significant difference between the mean attenuation values of different plaque types between DSCT, DECT, and SSCT: type IV: 11 HU/8 HU/19 HU; type Va: 44 HU/45 HU/52 HU; type Vb: 1088 HU/966 HU/1079 HU). The sensitivity for correct classification varied depending on the plaque type (type II = 0%, type III = 0%, type IV = 43%, type Va = 58%, Vb = 97%). Conclusion: Independent of the used acquisition technique, SSCT, DSCT and DECT show similar results for attenuation-based characterization of atherosclerotic coronary plaques.

  12. Analysis of fatty liver by CT values in obese children

    Energy Technology Data Exchange (ETDEWEB)

    Naganuma, Yoshihiro; Tomizawa, Shuichi; Ikarashi, Kozo; Tohyama, Jun; Ozawa, Kanzi [Niigata Hospital National Sanatorium, Kashiwazaki (Japan); Uchiyama, Makoto

    1996-06-01

    Liver attenuation values were measured by CT in 97 (183 times) obese children with ages 3 to 18 years and a diagnosis of fatty liver was made in 42 subjects. Liver/spleen ration from CT measurements showed a significant negative correlation with the percentage of standard body weight, and with the systolic pressure. In children with fatty liver, systolic pressure and serum GOT, GPT, ChE, TC, TG, ApoB and insulin were significantly higher than those in children without fatty liver. After a low-calorie dietary regimen and exercise therapy, the liver/spleen ratio and GPT improved in all children. The diagnosis of fatty infiltration (fatty liver) was made with a liver/spleen ratio of less than 1.0 as determined by the number of measurements taken, a reasonable criterion for the diagnosis of fatty liver by CT in children. There were some children with elevated GPT who showed normal CT findings. This may be caused by overnutrition which was associated with fatty infiltration, since GPT decreased in all these children after treatment. The present study suggests that CT is a useful procedure in diagnosing fatty liver, and in monitoring and determining efficacy of treatment in obese children. (author)

  13. Quantitative analysis of CT attenuation distribution patterns of nodule components for pathologic categorization of lung nodules

    Science.gov (United States)

    Zhou, Chuan; Chan, Heang-Ping; Wei, Jun; Hadjiiski, Lubomir M.; Chughtai, Aamer; Kazerooni, Ella A.

    2017-03-01

    We investigated the feasibility of classifying pathologic invasive nodules and pre-invasive or benign nodules by quantitative analysis of the CT attenuation distribution patterns and other radiomic features of lung nodule components. We developed a new 3D adaptive multi-component Expectation-Maximization (EM) analysis method to segment the solid and non-solid nodule components and the surrounding lung parenchymal region. Features were extracted to characterize the size, shape, and the CT attenuation distribution of the entire nodule as well as the individual regions. With permission of the National Lung Screening Trial (NLST) project, a data set containing the baseline low dose CT scans of 53 cases with known pathologic tumor type categorization was obtained. The 53 cases contain 45 invasive nodules (group 1) and 42 pre-invasive nodules (group 2). A logistic regression model (LRM) was built using leave-one-case-out resampling and receiver operating characteristic (ROC) analysis for classification of group 1 and group 2, using the pathologic categorization as ground truth. With 4 selected features, the LRM achieved a test area under the curve (AUC) value of 0.877+/-0.036. The results demonstrated that the pathologic invasiveness of lung adenocarcinomas could be categorized according to the CT attenuation distribution patterns of the nodule components manifested on LDCT images.

  14. Improved attenuation correction for respiratory gated PET/CT with extended-duration cine CT: a simulation study

    Science.gov (United States)

    Zhang, Ruoqiao; Alessio, Adam M.; Pierce, Larry A.; Byrd, Darrin W.; Lee, Tzu-Cheng; De Man, Bruno; Kinahan, Paul E.

    2017-03-01

    Due to the wide variability of intra-patient respiratory motion patterns, traditional short-duration cine CT used in respiratory gated PET/CT may be insufficient to match the PET scan data, resulting in suboptimal attenuation correction that eventually compromises the PET quantitative accuracy. Thus, extending the duration of cine CT can be beneficial to address this data mismatch issue. In this work, we propose to use a long-duration cine CT for respiratory gated PET/CT, whose cine acquisition time is ten times longer than a traditional short-duration cine CT. We compare the proposed long-duration cine CT with the traditional short-duration cine CT through numerous phantom simulations with 11 respiratory traces measured during patient PET/CT scans. Experimental results show that, the long-duration cine CT reduces the motion mismatch between PET and CT by 41% and improves the overall reconstruction accuracy by 42% on average, as compared to the traditional short-duration cine CT. The long-duration cine CT also reduces artifacts in PET images caused by misalignment and mismatch between adjacent slices in phase-gated CT images. The improvement in motion matching between PET and CT by extending the cine duration depends on the patient, with potentially greater benefits for patients with irregular breathing patterns or larger diaphragm movements.

  15. Characterization of Small Focal Renal Lesions: Diagnostic Accuracy with Single-Phase Contrast-enhanced Dual-Energy CT with Material Attenuation Analysis Compared with Conventional Attenuation Measurements.

    Science.gov (United States)

    Marin, Daniele; Davis, Drew; Roy Choudhury, Kingshuk; Patel, Bhavik; Gupta, Rajan T; Mileto, Achille; Nelson, Rendon C

    2017-09-01

    Purpose To determine whether single-phase contrast material-enhanced dual-energy material attenuation analysis improves the characterization of small (1-4 cm) renal lesions compared with conventional attenuation measurements by using histopathologic analysis and follow-up imaging as the clinical reference standards. Materials and Methods In this retrospective, HIPAA-compliant, institutional review board-approved study, 136 consecutive patients (95 men and 41 women; mean age, 54 years) with 144 renal lesions (111 benign, 33 malignant) measuring 1-4 cm underwent single-energy unenhanced and contrast-enhanced dual-energy computed tomography (CT) of the abdomen. For each renal lesion, attenuation measurements were obtained; attenuation change of greater than or equal to 15 HU was considered evidence of enhancement. Dual-energy attenuation measurements were also obtained by using iodine-water, water-iodine, calcium-water, and water-calcium material basis pairs. Mean lesion attenuation values and material densities were compared between benign and malignant renal lesions by using the two-sample t test. Diagnostic accuracy of attenuation measurements and dual-energy material densities was assessed and validated by using 10-fold cross-validation to limit the effect of optimistic bias. Results By using cross-validated optimal thresholds at 100% sensitivity, iodine-water material attenuation images significantly improved specificity for differentiating between benign and malignant renal lesions compared with conventional enhancement measurements (93% [103 of 111]; 95% confidence interval: 86%, 97%; vs 81% [90 of 111]; 95% confidence interval: 73%, 88%) (P = .02). Sensitivity with iodine-water and calcium-water material attenuation images was also higher than that with conventional enhancement measurements, although the difference was not statistically significant. Conclusion Contrast-enhanced dual-energy CT with material attenuation analysis improves specificity for

  16. Filtered back-projection reconstruction for attenuation proton CT along most likely paths.

    Science.gov (United States)

    Quiñones, C T; Létang, J M; Rit, S

    2016-05-07

    This work investigates the attenuation of a proton beam to reconstruct the map of the linear attenuation coefficient of a material which is mainly caused by the inelastic interactions of protons with matter. Attenuation proton computed tomography (pCT) suffers from a poor spatial resolution due to multiple Coulomb scattering (MCS) of protons in matter, similarly to the conventional energy-loss pCT. We therefore adapted a recent filtered back-projection algorithm along the most likely path (MLP) of protons for energy-loss pCT (Rit et al 2013) to attenuation pCT assuming a pCT scanner that can track the position and the direction of protons before and after the scanned object. Monte Carlo simulations of pCT acquisitions of density and spatial resolution phantoms were performed to characterize the new algorithm using Geant4 (via Gate). Attenuation pCT assumes an energy-independent inelastic cross-section, and the impact of the energy dependence of the inelastic cross-section below 100 MeV showed a capping artifact when the residual energy was below 100 MeV behind the object. The statistical limitation has been determined analytically and it was found that the noise in attenuation pCT images is 411 times and 278 times higher than the noise in energy-loss pCT images for the same imaging dose at 200 MeV and 300 MeV, respectively. Comparison of the spatial resolution of attenuation pCT images with a conventional straight-line path binning showed that incorporating the MLP estimates during reconstruction improves the spatial resolution of attenuation pCT. Moreover, regardless of the significant noise in attenuation pCT images, the spatial resolution of attenuation pCT was better than that of conventional energy-loss pCT in some studied situations thanks to the interplay of MCS and attenuation known as the West-Sherwood effect.

  17. Correction of oral contrast artifacts in CT-based attenuation correction of PET images using an automated segmentation algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Ahmadian, Alireza; Ay, Mohammad R.; Sarkar, Saeed [Medical Sciences/University of Tehran, Research Center for Science and Technology in Medicine, Tehran (Iran); Medical Sciences/University of Tehran, Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran (Iran); Bidgoli, Javad H. [Medical Sciences/University of Tehran, Research Center for Science and Technology in Medicine, Tehran (Iran); East Tehran Azad University, Department of Electrical and Computer Engineering, Tehran (Iran); Zaidi, Habib [Geneva University Hospital, Division of Nuclear Medicine, Geneva (Switzerland)

    2008-10-15

    Oral contrast is usually administered in most X-ray computed tomography (CT) examinations of the abdomen and the pelvis as it allows more accurate identification of the bowel and facilitates the interpretation of abdominal and pelvic CT studies. However, the misclassification of contrast medium with high-density bone in CT-based attenuation correction (CTAC) is known to generate artifacts in the attenuation map ({mu}map), thus resulting in overcorrection for attenuation of positron emission tomography (PET) images. In this study, we developed an automated algorithm for segmentation and classification of regions containing oral contrast medium to correct for artifacts in CT-attenuation-corrected PET images using the segmented contrast correction (SCC) algorithm. The proposed algorithm consists of two steps: first, high CT number object segmentation using combined region- and boundary-based segmentation and second, object classification to bone and contrast agent using a knowledge-based nonlinear fuzzy classifier. Thereafter, the CT numbers of pixels belonging to the region classified as contrast medium are substituted with their equivalent effective bone CT numbers using the SCC algorithm. The generated CT images are then down-sampled followed by Gaussian smoothing to match the resolution of PET images. A piecewise calibration curve was then used to convert CT pixel values to linear attenuation coefficients at 511 keV. The visual assessment of segmented regions performed by an experienced radiologist confirmed the accuracy of the segmentation and classification algorithms for delineation of contrast-enhanced regions in clinical CT images. The quantitative analysis of generated {mu}maps of 21 clinical CT colonoscopy datasets showed an overestimation ranging between 24.4% and 37.3% in the 3D-classified regions depending on their volume and the concentration of contrast medium. Two PET/CT studies known to be problematic demonstrated the applicability of the technique

  18. Hemodynamic significance of coronary stenosis by vessel attenuation measurement on CT compared with adenosine perfusion MRI

    Energy Technology Data Exchange (ETDEWEB)

    Dekker, Martijn A.M. den; Pelgrim, Gert Jan; Pundziute, Gabija; Heuvel, Edwin R. van den; Oudkerk, Matthijs; Vliegenthart, Rozemarijn, E-mail: r.vliegenthart@umcg.nl

    2015-01-15

    Highlights: • The majority of anatomical coronary stenoses do not cause myocardial ischemia. • cCTA-derived CCO decrease expresses luminal density gradient across stenosis. • CCO decrease differentiates between anatomical stenoses with and without associated myocardial ischemia. • CCO decrease assessment can exclude the majority of stenoses without hemodynamic significance. - Abstract: Purpose: We assessed the association between corrected contrast opacification (CCO) based on coronary computed tomography angiography (cCTA) and inducible ischemia by adenosine perfusion magnetic resonance imaging (APMR). Methods: Sixty cardiac asymptomatic patients with extra-cardiac arterial disease (mean age 64.4 ± 7.7 years; 78% male) underwent cCTA and APMR. Luminal CT attenuation values (Hounsfield Units) were measured in coronary arteries from proximal to distal, with additional measurements across sites with >50% lumen stenosis. CCO was calculated by dividing coronary CT attenuation by descending aorta CT attenuation. A reversible perfusion defect on APMR was considered as myocardial ischemia. Results: In total, 169 coronary stenoses were found. Seven patients had 8 perfusion defects on APMR, with 11 stenoses in corresponding vessels. CCO decrease across stenoses with hemodynamic significance was 0.144 ± 0.112 compared to 0.047 ± 0.104 across stenoses without hemodynamic significance (P = 0.003). CCO decrease in lesions with and without anatomical stenosis was similar (0.054 ± 0.116 versus 0.052 ± 0.101; P = 0.89). Using 0.20 as preliminary CCO decrease cut-off, hemodynamic significance would be excluded in 82.9% of anatomical stenoses. Conclusions: CCO decrease across coronary stenosis is associated with myocardial ischemia on APMR. CCO based on common cCTA data is a novel method to assess hemodynamic significance of anatomical stenosis.

  19. PET/CT with intravenous contrast can be used for PET attenuation correction in cancer patients

    DEFF Research Database (Denmark)

    Berthelsen, A K; Holm, S; Loft, A

    2005-01-01

    correction, but this may result in a bias in the attenuation factors. The clinical significance of this bias has not been established. Our aim was to perform a prospective clinical study where each patient had CT performed with and without IV contrast agent to establish whether PET/CT with IV contrast can...

  20. Effect of Attenuation Correction on Regional Quantification Between PET/MR and PET/CT

    DEFF Research Database (Denmark)

    Teuho, Jarmo; Johansson, Jarkko; Linden, Jani

    2016-01-01

    UNLABELLED: A spatial bias in brain PET/MR exists compared with PET/CT, because of MR-based attenuation correction. We performed an evaluation among 4 institutions, 3 PET/MR systems, and 4 PET/CT systems using an anthropomorphic brain phantom, hypothesizing that the spatial bias would be minimize...

  1. Added diagnostic value of CT attenuation correction for spinal lesions in SPECT bone imaging%CT衰减校正对脊柱病灶SPECT显像的增益价值

    Institute of Scientific and Technical Information of China (English)

    余浩军; 张一秋; 李蓓蕾; 蔡良; 陈曙光; 石洪成

    2016-01-01

    目的 探讨CTAC在提高脊柱病灶SPECT图像质量及对良恶性判断的诊断信心方面是否具有增益价值.方法 75例[男47例,女28例,年龄(56.6±12.8)岁]全身骨显像示脊柱放射性异常浓聚病灶的患者,因全身骨显像无法明确良恶性诊断行SPECT/CT显像.将脊柱病灶NACSPECT图像与CTAC SPECT图像按5分法(5分,优秀;4分,良好;3分,中等;2分,一般;1分,较差)评分,并对图像良恶性诊断信心按4分法(4分,肯定;3分,基本肯定;2分,可能;1分,无法判断良恶性)评分,以手术病理结果为“金标准”,评价CTAC对脊柱病灶SPECT显像的增益价值.采用Wilcoxon 配对符号秩和检验比较评分差异.结果 有37.3%(28/75)的患者CTAC图像质量评分较NAC图像质量评分上升,60.0% (45/75)的患者评分不变,2.7%(2/75)的患者评分下降,CTAC对SPECT图像质量有显著改善(z=-4.747,P<0.001).CTAC对诊断信心评分无显著提高(z=-1.000,P>0.05).结论 CTAC可显著提高图像视觉质量较差的脊柱病灶SPECT图像质量,对视觉质量较好的SPECT图像意义不大;其对良恶性诊断信心无显著提升.%Objective To investigate the added value of CTAC for improving image quality and diagnostic efficiency of bone imaging in SPECT/CT.Methods Seventy-five patients (47 males,28 females,(56.6± 12.8) years) with abnormal uptake in planar whole-body bone scintigraphy underwent SPECT/CTfor differentiation of malignant from benign spinal lesions.NAC and CTAC SPECT images were classified based on 5-point scale (5:excellent,4:good,3:adequate,2:suboptimal,1:inadequate).The diagnostic confidence for both NAC and CTAC SPECT images were classified based on 4-point scale (4:definite,3:certain,2:equivocal,1:uninterpretable).The pathological results after surgery were used as gold standard to evaluate the added diagnostic value of CTAC for spinal lesions.Wilcoxon-signed rank sum test was used for data analysis.Results CTAC improved the image quality in 37

  2. CT-based attenuation and scatter correction compared with uniform attenuation correction in brain perfusion SPECT imaging for dementia

    Science.gov (United States)

    Gillen, Rebecca; Firbank, Michael J.; Lloyd, Jim; O'Brien, John T.

    2015-09-01

    This study investigated if the appearance and diagnostic accuracy of HMPAO brain perfusion SPECT images could be improved by using CT-based attenuation and scatter correction compared with the uniform attenuation correction method. A cohort of subjects who were clinically categorized as Alzheimer’s Disease (n=38 ), Dementia with Lewy Bodies (n=29 ) or healthy normal controls (n=30 ), underwent SPECT imaging with Tc-99m HMPAO and a separate CT scan. The SPECT images were processed using: (a) correction map derived from the subject’s CT scan or (b) the Chang uniform approximation for correction or (c) no attenuation correction. Images were visually inspected. The ratios between key regions of interest known to be affected or spared in each condition were calculated for each correction method, and the differences between these ratios were evaluated. The images produced using the different corrections were noted to be visually different. However, ROI analysis found similar statistically significant differences between control and dementia groups and between AD and DLB groups regardless of the correction map used. We did not identify an improvement in diagnostic accuracy in images which were corrected using CT-based attenuation and scatter correction, compared with those corrected using a uniform correction map.

  3. Ultra-low dose CT attenuation correction for PET/CT: analysis of sparse view data acquisition and reconstruction algorithms

    Science.gov (United States)

    Rui, Xue; Cheng, Lishui; Long, Yong; Fu, Lin; Alessio, Adam M.; Asma, Evren; Kinahan, Paul E.; De Man, Bruno

    2015-09-01

    For PET/CT systems, PET image reconstruction requires corresponding CT images for anatomical localization and attenuation correction. In the case of PET respiratory gating, multiple gated CT scans can offer phase-matched attenuation and motion correction, at the expense of increased radiation dose. We aim to minimize the dose of the CT scan, while preserving adequate image quality for the purpose of PET attenuation correction by introducing sparse view CT data acquisition. We investigated sparse view CT acquisition protocols resulting in ultra-low dose CT scans designed for PET attenuation correction. We analyzed the tradeoffs between the number of views and the integrated tube current per view for a given dose using CT and PET simulations of a 3D NCAT phantom with lesions inserted into liver and lung. We simulated seven CT acquisition protocols with {984, 328, 123, 41, 24, 12, 8} views per rotation at a gantry speed of 0.35 s. One standard dose and four ultra-low dose levels, namely, 0.35 mAs, 0.175 mAs, 0.0875 mAs, and 0.043 75 mAs, were investigated. Both the analytical Feldkamp, Davis and Kress (FDK) algorithm and the Model Based Iterative Reconstruction (MBIR) algorithm were used for CT image reconstruction. We also evaluated the impact of sinogram interpolation to estimate the missing projection measurements due to sparse view data acquisition. For MBIR, we used a penalized weighted least squares (PWLS) cost function with an approximate total-variation (TV) regularizing penalty function. We compared a tube pulsing mode and a continuous exposure mode for sparse view data acquisition. Global PET ensemble root-mean-squares-error (RMSE) and local ensemble lesion activity error were used as quantitative evaluation metrics for PET image quality. With sparse view sampling, it is possible to greatly reduce the CT scan dose when it is primarily used for PET attenuation correction with little or no measureable effect on the PET image. For the four ultra-low dose

  4. Ultra-low dose CT attenuation correction for PET/CT: analysis of sparse view data acquisition and reconstruction algorithms.

    Science.gov (United States)

    Rui, Xue; Cheng, Lishui; Long, Yong; Fu, Lin; Alessio, Adam M; Asma, Evren; Kinahan, Paul E; De Man, Bruno

    2015-10-07

    For PET/CT systems, PET image reconstruction requires corresponding CT images for anatomical localization and attenuation correction. In the case of PET respiratory gating, multiple gated CT scans can offer phase-matched attenuation and motion correction, at the expense of increased radiation dose. We aim to minimize the dose of the CT scan, while preserving adequate image quality for the purpose of PET attenuation correction by introducing sparse view CT data acquisition.We investigated sparse view CT acquisition protocols resulting in ultra-low dose CT scans designed for PET attenuation correction. We analyzed the tradeoffs between the number of views and the integrated tube current per view for a given dose using CT and PET simulations of a 3D NCAT phantom with lesions inserted into liver and lung. We simulated seven CT acquisition protocols with {984, 328, 123, 41, 24, 12, 8} views per rotation at a gantry speed of 0.35 s. One standard dose and four ultra-low dose levels, namely, 0.35 mAs, 0.175 mAs, 0.0875 mAs, and 0.043 75 mAs, were investigated. Both the analytical Feldkamp, Davis and Kress (FDK) algorithm and the Model Based Iterative Reconstruction (MBIR) algorithm were used for CT image reconstruction. We also evaluated the impact of sinogram interpolation to estimate the missing projection measurements due to sparse view data acquisition. For MBIR, we used a penalized weighted least squares (PWLS) cost function with an approximate total-variation (TV) regularizing penalty function. We compared a tube pulsing mode and a continuous exposure mode for sparse view data acquisition. Global PET ensemble root-mean-squares-error (RMSE) and local ensemble lesion activity error were used as quantitative evaluation metrics for PET image quality.With sparse view sampling, it is possible to greatly reduce the CT scan dose when it is primarily used for PET attenuation correction with little or no measureable effect on the PET image. For the four ultra-low dose levels

  5. Mosaic Pattern of Lung Attenuation on Chest CT in Patients with Pulmonary Hypertension

    Directory of Open Access Journals (Sweden)

    Kamonpun Ussavarungsi

    2015-09-01

    Full Text Available A mosaic pattern of lung attenuation on chest computed tomography (CT may be due to various etiologies. There is limited published data on CT results when used to evaluate pulmonary hypertension (PH. We retrospectively studied the frequency of mosaic pattern in patients with PH and the cause of the PH by diagnostic group, as well as the correlation between the mosaic pattern and the following: demographics, severity of the PH, main pulmonary artery (PA size, PA/aorta (PA/Ao ratio, pulmonary function tests (PFT, and ventilation perfusion scan results. Overall, 18% of the cohort had CT mosaic pattern (34/189. Mosaic pattern was present in 17/113 (15% in Group 1 pulmonary arterial hypertension, 5/13 (28% in Group 2 pulmonary venous hypertension and 8/50 (16% in Group 3 PH. Conversely, Group 4 chronic thromboembolic PH was more prevalent in 4/8 (50%. Main PA size, PA/Ao ratio, and segmental perfusion defect were positively associated with mosaic pattern. In contrast, factors such as age, gender, body mass index, functional class, hemodynamic data, and PFT values were not associated with mosaic pattern. Mosaic pattern is not specific as an isolated finding for distinguishing the subtype of PH.

  6. Automatic detection of cardiovascular risk in CT attenuation correction maps in Rb-82 PET/CTs

    Science.gov (United States)

    Išgum, Ivana; de Vos, Bob D.; Wolterink, Jelmer M.; Dey, Damini; Berman, Daniel S.; Rubeaux, Mathieu; Leiner, Tim; Slomka, Piotr J.

    2016-03-01

    CT attenuation correction (CTAC) images acquired with PET/CT visualize coronary artery calcium (CAC) and enable CAC quantification. CAC scores acquired with CTAC have been suggested as a marker of cardiovascular disease (CVD). In this work, an algorithm previously developed for automatic CAC scoring in dedicated cardiac CT was applied to automatic CAC detection in CTAC. The study included 134 consecutive patients undergoing 82-Rb PET/CT. Low-dose rest CTAC scans were acquired (100 kV, 11 mAs, 1.4mm×1.4mm×3mm voxel size). An experienced observer defined the reference standard with the clinically used intensity level threshold for calcium identification (130 HU). Five scans were removed from analysis due to artifacts. The algorithm extracted potential CAC by intensity-based thresholding and 3D connected component labeling. Each candidate was described by location, size, shape and intensity features. An ensemble of extremely randomized decision trees was used to identify CAC. The data set was randomly divided into training and test sets. Automatically identified CAC was quantified using volume and Agatston scores. In 33 test scans, the system detected on average 469mm3/730mm3 (64%) of CAC with 36mm3 false positive volume per scan. The intraclass correlation coefficient for volume scores was 0.84. Each patient was assigned to one of four CVD risk categories based on the Agatston score (0-10, 11-100, 101-400, Cohen's linearly weighted κ0.82). Automatic detection of CVD risk based on CAC scoring in rest CTAC images is feasible. This may enable large scale studies evaluating clinical value of CAC scoring in CTAC data.

  7. Adrenal adenomas: relationship between histologic lipid-rich cells and CT attenuation number

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Takayuki E-mail: yamataka@rad.med.tohoku.ac.jp; Ishibashi, Tadashi; Saito, Haruo; Matsuhashi, Toshio; Majima, Kazuhiro; Tsuda, Masashi; Takahashi, Shoki; Moriya, Takuya

    2003-11-01

    Objective: To evaluate the relationship between lipid-rich cells of the adrenal adenoma and precontrast computed tomographic (CT) attenuation numbers in three clinical groups. Materials and Methods: Thirty-five surgically resected adrenal adenomas were used. The clinical diagnoses of the patients included 13 cases of primary aldosteronism, 15 cases of Cushing's syndrome, and 7 non-functioning tumors. The number of lipid-rich clear cells was counted using a microscopic eyepiece grid that contained 100 squares. The results were expressed as the percentages of lipid-rich areas. Results: There was a strong inverse linear relationship between the percentage of lipid-rich cells and the precontrast CT attenuation number (R{sup 2}=0.724, P<0.0001). There were significantly more lipid-rich cells in the primary aldosteronism and non-functioning tumor cases compared to cases of Cushing's syndrome (P=0.007 and 0.015, respectively). The CT attenuation numbers of the primary aldosteronism cases were significantly lower than those of Cushing's syndrome (P=0.0052). Furthermore, the CT attenuation numbers of the non-functioning tumor cases were lower than those of Cushing's syndrome cases. Conclusion: We showed that adrenal adenomas in primary aldosteronism and non-functioning tumors contain significantly more lipid-rich cells than those in Cushing's syndrome. They also showed significantly lower attenuation than that in Cushing's syndrome on CT scans. Our results suggest that precontrast CT attenuation numbers may be helpful in the differentiation of adenomas from non-adenomatous lesions, which include malignancies.

  8. Intravenous contrast-enhanced CT can be used for CT-based attenuation correction in clinical 111In-octreotide SPECT/CT

    DEFF Research Database (Denmark)

    Klausen, Thomas Levin; Mortensen, Jann; de Nijs, Robin

    2015-01-01

    in a central volume. Ten patients referred for (111)In-octreotide scintigraphy were scanned according to our clinical (111)In-SPECT/CT protocol including a topogram, a LD (140 kVp), and a FD (120 kVp). The FD/contrast-enhanced CT was acquired in both arterial (FDAP) and venous phase (FDVP) following a mono......BACKGROUND: CT-based attenuation correction (CT-AC) using contrast-enhancement CT impacts (111)In-SPECT image quality and quantification. In this study we assessed and evaluated the effect. METHODS: A phantom (5.15 L) was filled with an aqueous solution of In-111. Three SPECT/CT scans were...... performed: (A) no IV contrast, (B) with 100-mL IV contrast, and (C) with 200-mL IV contrast added. Scan protocol included a localization CT, a low-dose CT (LD), and a full-dose CT (FD). Phantom, LD and FD scan series were performed at 90, 120, and 140 kVp. Phantom data were evaluated looking at mean counts...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-11-15

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

  10. The value of SPECT/CT in carpal boss

    Energy Technology Data Exchange (ETDEWEB)

    Bhure, Ujwal; Huellner, Martin W.; Gruenig, Hannes; Zander, Andrea; Sol Perez Lago, Maria del; Strobel, Klaus [Cantonal Hospital Lucerne, Nuclear Medicine and Radiology, Lucerne (Switzerland); Hug, Urs [Cantonal Hospital Lucerne, Department of Hand and Plastic Surgery, Lucerne (Switzerland)

    2015-11-15

    To assess the value of SPECT/CT in patients with carpal boss (CB). In 24 wrists with CB (18 right-sided, 6 left-sided) in 21 patients, planar images and SPECT/CT images were obtained. Three patients had bilateral CB. The grade of uptake (0 absent, 1 low, 2 moderate, 3 high) on planar imaging and SPECT/CT was assessed and compared with CT findings, clinical symptoms and follow-up findings. CB affected carpometacarpal joint II in 4 wrists, carpometacarpal joint III in 17 wrists and both carpometacarpal joints II and III in 3 wrists. Of the 24 CB, 12 (50 %) were active (i.e. increased radionuclide uptake) on planar images and 18 (75 %) on SPECT/CT images. Of the 17 symptomatic CB, 10 (59 %) were active on planar images and 14 (82 %) were active (mean grade 1.9, range 1 - 3) on SPECT/CT images. Of the 7 asymptomatic CB, 2 were active on planar images and 4 were active (mean grade 1.25, range 1 - 2) on SPECT/CT images. CT alone showed CB in all patients and an accessory ossicle (os styloideum) in 8 wrists. MR imaging was available in 7 patients and positive for CB in 5 (sensitivity 71 %). Plain radiographs were available in 17 patients and positive in 10 (59 %). Therapeutic infiltration of the CB was performed in 9 patients, and resection of the CB in 7 patients. SPECT/CT provides important morphological and metabolic information for the clinical assessment of CB, but because SPECT/CT tends to overestimate the clinical importance of CB, we recommend that planar images should still be obtained. (orig.)

  11. Subject-specific bone attenuation correction for brain PET/MR: can ZTE-MRI substitute CT scan accurately?

    Science.gov (United States)

    Khalifé, Maya; Fernandez, Brice; Jaubert, Olivier; Soussan, Michael; Brulon, Vincent; Buvat, Irène; Comtat, Claude

    2017-10-01

    In brain PET/MR applications, accurate attenuation maps are required for accurate PET image quantification. An implemented attenuation correction (AC) method for brain imaging is the single-atlas approach that estimates an AC map from an averaged CT template. As an alternative, we propose to use a zero echo time (ZTE) pulse sequence to segment bone, air and soft tissue. A linear relationship between histogram normalized ZTE intensity and measured CT density in Hounsfield units (HU ) in bone has been established thanks to a CT-MR database of 16 patients. Continuous AC maps were computed based on the segmented ZTE by setting a fixed linear attenuation coefficient (LAC) to air and soft tissue and by using the linear relationship to generate continuous μ values for the bone. Additionally, for the purpose of comparison, four other AC maps were generated: a ZTE derived AC map with a fixed LAC for the bone, an AC map based on the single-atlas approach as provided by the PET/MR manufacturer, a soft-tissue only AC map and, finally, the CT derived attenuation map used as the gold standard (CTAC). All these AC maps were used with different levels of smoothing for PET image reconstruction with and without time-of-flight (TOF). The subject-specific AC map generated by combining ZTE-based segmentation and linear scaling of the normalized ZTE signal into HU was found to be a good substitute for the measured CTAC map in brain PET/MR when used with a Gaussian smoothing kernel of 4~mm corresponding to the PET scanner intrinsic resolution. As expected TOF reduces AC error regardless of the AC method. The continuous ZTE-AC performed better than the other alternative MR derived AC methods, reducing the quantification error between the MRAC corrected PET image and the reference CTAC corrected PET image.

  12. The value of early CT in complicated childhood pneumonia

    Energy Technology Data Exchange (ETDEWEB)

    Tan Kendrick, A.P. [Department of Diagnostic Imaging, Kandang Kerbau Women' s and Children' s Hospital (Singapore); Ling, Ho [Department of Paediatric Medicine, Kandang Kerbau Women' s and Children' s Hospital (Singapore); Subramaniam, Ramnath; Joseph, Vijeyakaran T. [Department of Paediatric Surgery, Kandang Kerbau Women' s and Children' s Hospital (Singapore)

    2002-01-01

    Objective. To investigate the value of CT in complicated childhood pneumonia and its role in early intervention when chest radiography (CXR) is non-contributory. Materials and methods. Forty-two immunocompetent children, aged 1-11 years, admitted for community-acquired pneumonia from October 1997 to September 1999, had 42 contrast-enhanced CT scans and frontal chest radiographs on the same day, which were assessed independently. CT was performed when the patient remained unwell and the CXR images showed failure of resolution despite 7-10 days of antibiotics and/or drainage with urokinase therapy. Results. Compared to CT, CXR revealed suboptimal accuracy rates of lobar involvement (84%), chest tube placement (73%), fluid loculation (42%), abscess formation (40%) and bronchopleural fistulae (33%). It could not assess parenchymal or pleural complications such as cavitary necrosis, early abscess formation, empyemas or pericardial effusions. On the basis of the CT findings and poor clinical progress, 16 patients underwent surgical intervention with the aid of video-assisted thorascopic surgery (VATS). The CT features correlated well with surgical findings. Ten cases required pleural decortication while six with destructive or necrotic lung lesions had surgical resection. Debridement was difficult when the pleura had become thick and fibrotic. Streptococcus pneumoniae was the offending organism in 81% of cases. The right side was affected in 67% of cases. Conclusions. In complicated childhood pneumonia, CT is far superior to CXR in revealing pleural and parenchymal complications, which may require early surgical intervention. (orig.)

  13. Neurological ct Scan Value for Ictus in Cienfuegos Province

    Directory of Open Access Journals (Sweden)

    Idaylí Pérez Rodríguez

    2007-05-01

    Full Text Available Backgrounds: CT scan constitutes a very important technique in the diagnosis of the cerebrovascular disease. The impact this transcendental event had and will continue having in the medicine area is impossible to state in terms of dimensions during the next years. Objective: To determine the neurological CT scan value for ictus in our milieu. Methods: A retrospective, prospective, longitudinal study of a series of cases performed during a review of statistical reports as well as that of Stroke data base which stores information of patients with neurocitus in our province, and which is based on others aspects founds by means of neurological CT scan. Results: CT scan allowed us to diagnose the type of cerebrovascular event (75.55 % ischemic events, 24.45% hemorrhagic events. It also contributed to the necessary data such as the localization (with predominium of 35.55% in more than one area, and 7.40 % in the parietal area. The presence of cerebral edema was verified in 16.29% of the cases as well as displacement of the midline in 7.40 % both associated to a torpid evolution. It incorporated the Fisher and Le Roux scales showing their prognosis value with elevated measures for deceased patients and decreased values for survivors without disability. Conclusions: The diagnosis and prognosis value were proved as well as CT scan behavior in our milieu. These aspects permit the reliable introduction of new therapeutic modalities in our province.

  14. Measurement of pulmonary parenchymal attenuation: use of spirometric gating with quantitative CT.

    Science.gov (United States)

    Kalender, W A; Rienmüller, R; Seissler, W; Behr, J; Welke, M; Fichte, H

    1990-04-01

    A new approach to reproducible measurement of lung attenuation and structure by means of respiratory-gated computed tomography (CT) was developed. The patient breathes through a microcomputer-controlled pocket spirometer during the complete CT examination, starting with a measurement of the vital capacity. At a user-selected respiratory level, the CT scan is triggered and air flow is inhibited mechanically. To exclude operator-related reproducibility errors, evaluation is based on semiautomated algorithms that isolate lung parenchyma by fast contour tracing. In a study on one volunteer, measurement of lung attenuation changed by a factor of about 2.6 (-895 to -730 HU) as a function of inspirational status. Reproducibility on the order of 5% or better can be achieved only with tight spirometric control of respiration.

  15. What is the benefit of CT-based attenuation correction in myocardial perfusion SPET?

    Science.gov (United States)

    Apostolopoulos, Dimitrios J; Savvopoulos, Christos

    2016-01-01

    In multimodality imaging, CT-derived transmission maps are used for attenuation correction (AC) of SPET or PET data. Regarding SPET myocardial perfusion imaging (MPI), however, the bene����t of CT-based AC (CT-AC) has been questioned. Although most attenuation-related artifacts are removed by this technique, new false defects may appear while some true perfusion abnormalities may be masked. The merits and the drawbacks of CT-AC in MPI SPET are reviewed and discussed in this editorial. In conclusion, CT-AC is most helpful in men, overweight in particular, and in those with low or low to intermediate pre-test probability of coronary artery disease (CAD). It is also useful for the evaluation of myocardial viability. In high-risk patients though, CT-AC may underestimate the presence or the extent of CAD. In any case, corrected and non-corrected images should be viewed side-by-side and both considered in the interpretation of the study.

  16. The value of brain CT findings in acute methanol toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Taheri, Morteza Sanei [Department of Radiology, Shohada Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Poison Control Center, Loghman-Hakim Poison Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)], E-mail: saneim@yahoo.com; Moghaddam, Hossein Hassanian [Poison Control Center, Loghman-Hakim Poison Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Moharamzad, Yashar; Dadgari, Shahrzad [Department of Radiology, Shohada Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nahvi, Vahideh [Poison Control Center, Loghman-Hakim Poison Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2010-02-15

    Objective: Due to depressant effects of methanol on the central nervous system, brain computed tomography (CT) scan has been introduced as a diagnostic device in methanol intoxication. The authors aimed to present brain CT findings in patients with acute methanol intoxication and to determine signs associated with death. Materials and methods: This cohort study involved 42 consecutive patients with acute methanol intoxication. Inclusion criteria were consisted of characteristic clinical presentation of methanol poisoning, and metabolic acidosis with increased anion and osmolar gaps. Brain CT scans without contrast medium were obtained. To determine the association between the CT findings and death, the chi-square test or the Fisher's exact test, odds ratio (OR) and its 95% confidence interval (95% CI) were calculated. Results: Twenty-eight patients (66.6%) had a total of 55 abnormal findings on brain CT, in which bilateral putaminal hypodense lesions was the most common manifestation (27 cases, 96.4%). Putaminal hemorrhage with varying degrees was observed in 7 patients (25%). Six patients (21.4%) had low attenuation lesions in the subcortical white matter of the insula. A significant association was observed between putaminal hemorrhage (OR = 8, 95% CI = 1.187-53.93, P = 0.018) and subcortical necrosis of the insula (OR = 11, 95% CI = 1.504-80.426, P = 0.007) with death. Conclusion: In addition to clinical and laboratory findings, presence of putaminal hemorrhage and insular subcortex white matter necrosis are associated with a poor clinical outcome in patients with methanol poisoning.

  17. Value of computed tomography in diagnosis of intestinal diseases. CT findings in nontumoral bowel diseases

    Energy Technology Data Exchange (ETDEWEB)

    Fujikawa, Koichi; Yamane, Kosuke; Nakanishi, Tadashi; Miura, Yoshio; Kato, Yoshitaka; Yahata, Noriko; Iwamoto, Toshiyuki; Katayama, Hiroshi; Katsuta, Shizutomo

    1987-03-01

    CT findings of 46 cases with inflammatory and other nontumoral bowel diseases were retrospectively studied. Patients were given 500 to 1000 ml of lukewarm water orally or rectally to distend the intestinal lumen. In all cases water-soluble iodine contrast media was administered intravenously. The CT findings in Crohn's disease included mural thickening, luminal narrowing, bowel wall enhancement, wall rigidity, serration of intestinal border, dilatation of mesenteric vessels, periintestinal blurring (inflamatory reaction of mesentery), fibrofatty proliferation, effusion, abscess and fistula. Many of these findings suggested the transmural nature of the disease and gave diagnostic clues of the disease. In cases with ulcerative colitis, thickening of bowel wall was insignificant and extraintestinal complications were absent. CT appears to play an important role in distinguishing Crohn's disease and ulcerative colitis. Luminal narrowing and mural thickening were also observed in a case with intestinal ischemia, but these mural changes were not accompanied by mesenteric abnormalities to the degree of Crohn's disease. In cases with penetrating peptic ulcer and diverticulitis, CT demonstrated inflammatory reactions of surrounding tissue such as thickening of neighboring fascia, increase in attenuation value of mesenteric fat, effusion and abscess. Even in cases with confusing clinical symptoms, appendicitis was easily diagnosed on CT which showed swelling of appendix and inflammatory changes of surrounding structures. Mechanical obstruction of the intestine could be identified on CT by a notable change of luminal sizes at the site of obstruction. CT appearances of intussusception were distinctive and a soft tissue mass (intussusceptum) and mesenteric fat was seen within a markedly dilated intussuscipiens. CT could also reveal pancreatitis and splenic infarction as the causes of clinically-undiagnosed paralytic ileus. (J.P.N.).

  18. Evaluation of a bilinear model for attenuation correction using CT numbers generated from a parametric method.

    Science.gov (United States)

    Martinez, L C; Calzado, A

    2016-01-01

    A parametric model is used for the calculation of the CT number of some selected human tissues of known compositions (Hi) in two hybrid systems, one SPECT-CT and one PET-CT. Only one well characterized substance, not necessarily tissue-like, needs to be scanned with the protocol of interest. The linear attenuation coefficients of these tissues for some energies of interest (μ(i)) have been calculated from their tabulated compositions and the NIST databases. These coefficients have been compared with those calculated with the bilinear model from the CT number (μ(B)i). No relevant differences have been found for bones and lung. In the soft tissue region, the differences can be up to 5%. These discrepancies are attributed to the different chemical composition for the tissues assumed by both methods.

  19. Predictive value of low tube voltage and dual-energy CT for successful shock wave lithotripsy: an in vitro study.

    Science.gov (United States)

    Largo, Remo; Stolzmann, Paul; Fankhauser, Christian D; Poyet, Cédric; Wolfsgruber, Pirmin; Sulser, Tullio; Alkadhi, Hatem; Winklhofer, Sebastian

    2016-06-01

    This study investigates the capabilities of low tube voltage computed tomography (CT) and dual-energy CT (DECT) for predicting successful shock wave lithotripsy (SWL) of urinary stones in vitro. A total of 33 urinary calculi (six different chemical compositions; mean size 6 ± 3 mm) were scanned using a dual-source CT machine with single- (120 kVp) and dual-energy settings (80/150, 100/150 Sn kVp) resulting in six different datasets. The attenuation (Hounsfield Units) of calculi was measured on single-energy CT images and the dual-energy indices (DEIs) were calculated from DECT acquisitions. Calculi underwent SWL and the number of shock waves for successful disintegration was recorded. The prediction of required shock waves regarding stone attenuation/DEI was calculated using regression analysis (adjusted for stone size and composition) and the correlation between CT attenuation/DEI and the number of shock waves was assessed for all datasets. The median number of shock waves for successful stone disintegration was 72 (interquartile range 30-361). CT attenuation/DEI of stones was a significant, independent predictor (P waves with the best prediction at 80 kVp (β estimate 0.576) (P waves ranged between ρ = 0.31 and 0.68 showing the best correlation at 80 kVp (P < 0.001). The attenuation of urinary stones at low tube voltage CT is the best predictor for successful stone disintegration, being independent of stone composition and size. DECT shows no added value for predicting the success of SWL.

  20. The value of X-ray CT in orbital fractures

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Myung Hee; Lee, Jae Mun; Kim, Choon Yul; Bahk, Yong Whee [Catholic Medical College, Seoul (Korea, Republic of)

    1986-08-15

    On the pulse from the trauma transiting to posterior side of the orbit, orbital fractures are occurred through the weak point of the orbital wall. Invagination of soft tissue or entrapment of muscles may be associated with orbital fracture. In condition of inaccurate diagnosis, appropriate surgical repairment is impossible and complication such as diplopia or enophthalmia are developed. CT scan is diagnostic procedure which demonstrates accurately the site and state of orbital fracture, and its associated findings. The authors has been studied in 21 orbital CT scan to evaluate the relative value of plain X rays and CT scans in the diagnosis of orbital fractures during the period from January 1982 to September 1985. The conclusions were as follows: 1. Diagnostic rate was 100% by CT, 40% by initial and 80% by retrospective interpretation of conventional X-ray films. 2. Low X-ray diagnostic rate of medical wall fractures (26.7%) was due to thinness of the bone. 3. Medial wall fractures were associated with floor fractures in 46%. 4. Orbital soft tissue injuries and abnormalities of PNS were precisely evaluated by CT scan.

  1. Diagnostic value of CT in pelvic fracture by trauma

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Kyung Sook; Kang, Hyun Il; Suh, Myung Ok; Lee, Yul; Chung, Soo Young; Bae, Sang Hoon; Yoon, Jong Sup [College of Medicine Hallym University, Choonchun (Korea, Republic of)

    1987-06-15

    In order to determine the diagnostic value of CT in pelvic trauma, esp. acetabular fracture, we analysed 32 cases of pelvic trauma with conventional radiographic and computed tomographic findings. The results were as follows : 1. There were 26 males and 6 female and peak age span was 4th decade. 2. In 32 cases of acetabular fractures, single column fracture were diagnosed in 20 cases and two column fracture in 12 cases by CT. Among single column fractures, anterior column fractures were 12 cases and posterior column fractures were 8 cases. Complex fracture was most common type in two column fractures. 3. In 32 cases of acetabular fractures diagnosed by CT, 18 cases could be detected by plain X-ray. 4. Intraarticular bony fragments were detected on CT in 11 cases and on plain X-ray in 2 cases. 5. Combined soft issue injuries were 13 cases of pelvic hematoma, 1 case of retroperitoneal hematoma and 2 cases of hemarthrosis. 6. CT was useful in acetabular injury to delineated the extent and type of fracture, localized intraarticular bony fragments, characterize joint dislocation and detect the combined soft tissue injury.

  2. Clinical Applications of a CT Window Blending Algorithm: RADIO (Relative Attenuation-Dependent Image Overlay).

    Science.gov (United States)

    Mandell, Jacob C; Khurana, Bharti; Folio, Les R; Hyun, Hyewon; Smith, Stacy E; Dunne, Ruth M; Andriole, Katherine P

    2017-06-01

    A methodology is described using Adobe Photoshop and Adobe Extendscript to process DICOM images with a Relative Attenuation-Dependent Image Overlay (RADIO) algorithm to visualize the full dynamic range of CT in one view, without requiring a change in window and level settings. The potential clinical uses for such an algorithm are described in a pictorial overview, including applications in emergency radiology, oncologic imaging, and nuclear medicine and molecular imaging.

  3. Prevalence of Vertebral Compression Fractures on Routine CT Scans According to L1 Trabecular Attenuation: Determining Relevant Thresholds for Opportunistic Osteoporosis Screening.

    Science.gov (United States)

    Graffy, Peter M; Lee, Scott J; Ziemlewicz, Timothy J; Pickhardt, Perry J

    2017-09-01

    Radiologists interpreting body CT scans may be the first to identify osteoporosis and associated vertebral fractures. This study correlates L1 trabecular attenuation measurements with prevalent vertebral body fractures in older adults undergoing routine CT. Mean L1 trabecular attenuation was measured at thoracoabdominal CT in 1966 consecutive adults (983 men and 983 women) 65 years and older (mean age, 74.1 ± 6.6 [SD] years). Sagittal reconstructions and lateral scouts were analyzed for moderate or severe thoracolumbar vertebral compression fractures according to the Genant semiquantitative assessment method. The diagnostic performance of L1 attenuation for the evaluation of prevalent vertebral fractures was assessed, including ROC curve analysis. A total of 162 (8.2%) individuals (mean age, 78.3 years; 66 men, 96 women) had at least one moderate or severe vertebral fracture. The mean L1 attenuation was 70.2 HU among patients with a prevalent fracture, whereas it was 132.3 HU among patients without fracture (p < 0.001). The prevalence of moderate or severe vertebral compression fractures was 32.5% when L1 attenuation was ≤ 90 HU. Prevalence increased to 49.2% with L1 attenuation of ≤ 50 HU. ROC curve analysis determined an optimal threshold of 90 HU (sensitivity = 86.9%, specificity = 83.9%), with a corresponding AUC of 0.895. The odds ratio of having a moderate or severe vertebral compression fracture was 31.9 for L1 attenuation ≤ 90 HU (95% CI, 20.2-50.5; p < 0.001). Patients with moderate or severe vertebral compression fractures have significantly lower L1 attenuation values than patients who do not. L1 attenuation ≤ 90 HU may represent an optimal threshold for determining risk for osteoporotic vertebral fractures.

  4. Influence of CT-based attenuation correction on dopamine transporter SPECT with [(123)I]FP-CIT.

    Science.gov (United States)

    Lapa, Constantin; Spehl, Timo S; Brumberg, Joachim; Isaias, Ioannis U; Schlögl, Susanne; Lassmann, Michael; Herrmann, Ken; Meyer, Philipp T

    2015-01-01

    Dopamine transporter (DAT) imaging using single-photon emission computed tomography (SPECT) and (123)I-labelled radiopharmaceuticals like [(123)I]FP-CIT is an established part in the diagnostic work-up of parkinsonism. Guidelines recommend attenuation correction (AC), either by a calculated uniform attenuation matrix (calAC) or by a measured attenuation map (nowadays done by low-dose CT; CTAC). We explored the impact of CTAC compared to conventional calAC on diagnostic accuracy and the use of DAT availability as a biomarker of nigrostriatal integrity.Integrated SPECT/CT studies with [(123)I]FP-CIT were performed in patients with Parkinson's disease (PD; n = 15) and essential tremor (ET; n = 15). SPECT data was reconstructed with calAC, CTAC and without AC (noAC). Regional DAT availability was assessed by uniform volume-of-interest analyses providing striatal binding potential (BP ND) estimates. BP ND values were compared among methods and correlated with clinical parameters. Compared to calAC, both CTAC and noAC provided significantly lower, but highly linearly correlated BP ND estimates (R (2) = 0.96). Diagnostic performance to distinguish between patients with PD and those with ET was very high and did not differ between AC methods. CTAC and noAC data tended so show a stronger correlation with severity and duration of disease in PD and age in ET than did calAC. Defining the reference region on low-dose CT instead of SPECT did not consistently alter findings. [(123)I]FP-CIT SPECT provides a very high diagnostic accuracy for differentiation between PD and ET that is not dependent on the employed AC method. Preliminary correlations analyses suggest that BP ND estimates derived from CTAC represent a superior biomarker of nigrostriatal integrity.

  5. Coronary calcium score scans for attenuation correction of quantitative PET/CT {sup 13}N-ammonia myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Burkhard, Nina; Herzog, Bernhard A.; Husmann, Lars; Pazhenkottil, Aju P.; Burger, Irene A.; Buechel, Ronny R.; Valenta, Ines; Wyss, Christophe A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University of Zurich, Zurich Center for Integrative Human Physiology, Zurich (Switzerland)

    2010-03-15

    The aim of this study was to evaluate whether ECG-triggered coronary calcium scoring (CCS) scans can be used for attenuation correction (AC) to quantify myocardial blood flow (MBF) and coronary flow reserve (CFR) assessed by PET/CT with {sup 13}N-ammonia. Thirty-five consecutive patients underwent a {sup 13}N-ammonia PET/CT scan at rest and during standard adenosine stress. MBF values were calculated using AC maps obtained from the ECG-triggered CCS scan during inspiration and validated against MBF values calculated using standard non-gated transmission scans for AC. CFR was calculated as the ratio of hyperaemic over resting MBF. In all 35 consecutive patients intraobserver variability was assessed by blinded repeat analysis for both AC methods. There was an excellent correlation between CT AC and CCS for global MBF values at rest (n = 35, r = 0.94, p < 0.001) and during stress (n = 35, r = 0.97, p < 0.001) with narrow Bland-Altman (BA) limits of agreement (-0.21 to 0.10 ml/min per g and -0.41 to 0.30 ml/min per g) as well as for global CFR (n = 35, r = 0.96, p < 0.001, BA -0.27 to 0.34). The excellent correlation was preserved on the segmental MBF analysis for both rest and stress (n = 1190, r = 0.93, p < 0.001, BA -0.60 to 0.50) and for CFR (n = 595, r = 0.87, p < 0.001, BA -0.71 to 0.74). In addition, reproducibility proved excellent for global CFR by CT AC (n = 35, r = 0.91, p < 0.001, BA -0.42-0.58) and CCS scans (n = 35, r = 0.94, p < 0.001, BA -0.34-0.45). Use of attenuation maps from CCS scans allows accurate quantitative MBF and CFR assessment with {sup 13}N-ammonia PET/CT. (orig.)

  6. One registration multi-atlas-based pseudo-CT generation for attenuation correction in PET/MRI

    DEFF Research Database (Denmark)

    Arabi, H.; Zaidi, H.

    2016-01-01

    maps. The quantitative analysis revealed a good correlation between PET images corrected for attenuation using the proposed pseudo-CT generation approach and the corresponding CT images. The computational time is reduced by a factor of 1/N at the expense of a modest decrease in quantitative accuracy...

  7. Impact of CT attenuation correction method on quantitative respiratory-correlated (4D) PET/CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Nyflot, Matthew J., E-mail: nyflot@uw.edu [Department of Radiation Oncology, University of Washington, Seattle, Washington 98195-6043 (United States); Lee, Tzu-Cheng [Department of Bioengineering, University of Washington, Seattle, Washington 98195-6043 (United States); Alessio, Adam M.; Kinahan, Paul E. [Department of Radiology, University of Washington, Seattle, Washington 98195-6043 (United States); Wollenweber, Scott D.; Stearns, Charles W. [GE Healthcare, Waukesha, Wisconsin 53188 (United States); Bowen, Stephen R. [Department of Radiation Oncology, University of Washington, Seattle, Washington 98195-6043 and Department of Radiology, University of Washington, Seattle, Washington 98195-6043 (United States)

    2015-01-15

    Purpose: Respiratory-correlated positron emission tomography (PET/CT) 4D PET/CT is used to mitigate errors from respiratory motion; however, the optimal CT attenuation correction (CTAC) method for 4D PET/CT is unknown. The authors performed a phantom study to evaluate the quantitative performance of CTAC methods for 4D PET/CT in the ground truth setting. Methods: A programmable respiratory motion phantom with a custom movable insert designed to emulate a lung lesion and lung tissue was used for this study. The insert was driven by one of five waveforms: two sinusoidal waveforms or three patient-specific respiratory waveforms. 3DPET and 4DPET images of the phantom under motion were acquired and reconstructed with six CTAC methods: helical breath-hold (3DHEL), helical free-breathing (3DMOT), 4D phase-averaged (4DAVG), 4D maximum intensity projection (4DMIP), 4D phase-matched (4DMATCH), and 4D end-exhale (4DEXH) CTAC. Recovery of SUV{sub max}, SUV{sub mean}, SUV{sub peak}, and segmented tumor volume was evaluated as RC{sub max}, RC{sub mean}, RC{sub peak}, and RC{sub vol}, representing percent difference relative to the static ground truth case. Paired Wilcoxon tests and Kruskal–Wallis ANOVA were used to test for significant differences. Results: For 4DPET imaging, the maximum intensity projection CTAC produced significantly more accurate recovery coefficients than all other CTAC methods (p < 0.0001 over all metrics). Over all motion waveforms, ratios of 4DMIP CTAC recovery were 0.2 ± 5.4, −1.8 ± 6.5, −3.2 ± 5.0, and 3.0 ± 5.9 for RC{sub max}, RC{sub peak}, RC{sub mean}, and RC{sub vol}. In comparison, recovery coefficients for phase-matched CTAC were −8.4 ± 5.3, −10.5 ± 6.2, −7.6 ± 5.0, and −13.0 ± 7.7 for RC{sub max}, RC{sub peak}, RC{sub mean}, and RC{sub vol}. When testing differences between phases over all CTAC methods and waveforms, end-exhale phases were significantly more accurate (p = 0.005). However, these differences were driven by

  8. Functional Mechanism of Lung Mosaic CT Attenuation: Assessment with Deep-Inspiration Breath-Hold Perfusion SPECT-CT Fusion Imaging and Non-Breath-Hold Technegas SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Suga, K.; Yasuhiko, K. (Dept. of Radiology, St. Hill Hospital, Ube, Yamaguchi (Japan)); Iwanaga, H.; Tokuda, O.; Matsunaga, N. (Dept. of Radiology, Yamaguchi Univ. School of Medicine, Ube, Yamaguchi (Japan))

    2009-01-15

    Background: The functional mechanism of lung mosaic computed tomography attenuation (MCA) in pulmonary vascular disease (PVD) and obstructive airway disease (OAD) has not yet been fully clarified. Purpose: To clarify the mechanism of MCA in these diseases by assessing the relationship between regional lung function and CT attenuation change at MCA sites with the use of automated deep-inspiratory breath-hold (DIBrH) perfusion single-photon emission computed tomography (SPECT)-CT fusion images and non-breath-hold Technegas SPECT. Material and Methods: Subjects were 42 PVD patients (31 pulmonary thromboembolism, four primary/two secondary pulmonary hypertension, and five Takayasu arteritis), 12 OAD patients (five acute asthma, four obliterative bronchiolitis, and three bronchiectasis), and 12 normal controls, all of whom had MCA on DIBrH CT. The relationship between regional lung function and CT attenuation change at the lung slices with MCA was assessed using DIBrH perfusion SPECT-CT fusion images and non-breath-hold Technegas SPECT. The severity of perfusion defects with or without MCA was quantified by regions-of-interest analysis. Results: On DIBrH CT and perfusion SPECT, in contrast to no noticeable CT attenuation abnormality and fairly uniform perfusion in controls, 60 MCA and 274 perfusion defects in PVD patients, and 18 MCA and 61 defects in OAD patients were identified, with a total of 77 ventilation defects on Technegas SPECT in all patients. SPECT-CT correlation showed that, throughout the 78 MCA sites of all patients, lung perfusion was persistently decreased at low CT attenuation and preserved at intervening high CT attenuation, while lung ventilation was poorly correlated with CT attenuation change. The radioactivity ratios of reduced perfusion and the intervening preserved perfusion at the 78 perfusion defects with MCA were significantly lower than those at the remaining 257 defects without MCA (P<0.0001). Conclusion: Although further validation is

  9. Sparse signal reconstruction from polychromatic X-ray CT measurements via mass attenuation discretization

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Renliang; Dogandžić, Aleksandar [Iowa State University, Center for Nondestructive Evaluation, 1915 Scholl Road, Ames, IA 50011 (United States)

    2014-02-18

    We propose a method for reconstructing sparse images from polychromatic x-ray computed tomography (ct) measurements via mass attenuation coefficient discretization. The material of the inspected object and the incident spectrum are assumed to be unknown. We rewrite the Lambert-Beer’s law in terms of integral expressions of mass attenuation and discretize the resulting integrals. We then present a penalized constrained least-squares optimization approach for reconstructing the underlying object from log-domain measurements, where an active set approach is employed to estimate incident energy density parameters and the nonnegativity and sparsity of the image density map are imposed using negative-energy and smooth ℓ{sub 1}-norm penalty terms. We propose a two-step scheme for refining the mass attenuation discretization grid by using higher sampling rate over the range with higher photon energy, and eliminating the discretization points that have little effect on accuracy of the forward projection model. This refinement allows us to successfully handle the characteristic lines (Dirac impulses) in the incident energy density spectrum. We compare the proposed method with the standard filtered backprojection, which ignores the polychromatic nature of the measurements and sparsity of the image density map. Numerical simulations using both realistic simulated and real x-ray ct data are presented.

  10. Value of contrast-enhanced CT in detecting arterial injury with pelvic fracture

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Keigo; Iwase, Toshiki; Ohshima, Takeshi; Tsuboi, Masaki; Sugiura, Sakae; Hara, Suguru [Okazaki City Hospital, Aichi (Japan)

    2000-04-01

    Computed tomography (CT) was used for detecting ongoing pelvic hemorrhage in patients with pelvic fracture, and for deciding an indication or transcatheter arterial embolization. The authors compared plane CT with contrast-enhanced CT to examine the value of contrast-enhanced CT in detecting arterial injury with pelvic fracture. The diagnosis of arterial injury was made by angiography. CT-determined hematoma was detected in 10 parts according to bleeding sites. Each hematoma was counted and compared with angiographic arterial injury. Contrast-enhanced CT was more useful than plane CT, but the hemorrhage sites determined by contrast-enhanced CT were not identical with those of angiographic arterial injuries. (author)

  11. CT synthesis in the head & neck region for PET/MR attenuation correction: an iterative multi-atlas approach

    Energy Technology Data Exchange (ETDEWEB)

    Burgos, Ninon [Translational Imaging Group, Centre for Medical Image Computing, University College London, London (United Kingdom); Cardoso, M Jorge; Modat, Marc [Translational Imaging Group, Centre for Medical Image Computing, University College London, London (United Kingdom); Dementia Research Centre, University College London, London (United Kingdom); Punwani, Shonit [Division of Imaging, University College London Hospitals, London (United Kingdom); Centre for Medical Imaging, University College London, London (United Kingdom); Atkinson, David [Centre for Medical Imaging, University College London, London (United Kingdom); Arridge, Simon R [Centre for Medical Image Computing, University College London, London (United Kingdom); Hutton, Brian F [Institute of Nuclear Medicine, University College London Hospitals, London (United Kingdom); Ourselin, Sébastien [Translational Imaging Group, Centre for Medical Image Computing, University College London, London (United Kingdom); Dementia Research Centre, University College London, London (United Kingdom)

    2015-05-18

    In this work, we propose to tackle the problem of attenuation correction in the head and neck by synthesising CT from MR images using an iterative multi-atlas approach. The proposed method relies on pre-acquired T2-weighted MRI and CT images of the neck. For each subject, the MRI is non-rigidly mapped to the CT. To synthesise a pseudo CT, all the MRIs in the database are first registered to the target MRI. This registration consists of a robust affine followed by a non-rigid registration. The pseudo CT is obtained by fusing the mapped atlases according to their morphological similarity to the target. In contrast to CTs, T2 images do not provide a good estimate of the bone location. Combining multiple modalities at both the registration and image similarity stages is expected to provide more realistic mappings and to reduce the bias. An initial pseudo CT (pCT) is combined with the target MRI to form a MRI-pCT pair. The MRI-pCT pair is registered to all the MRI-CT pairs from the database. An improved pseudo CT is obtained by fusing the mapped MRI-CT pairs according to their morphological similarity to the target MRI-pCT pair. Results showed that the proposed CT synthesis algorithm based on a multi-atlas information propagation scheme and iterative process is able to synthesise pseudo CT images in a region challenging for registration algorithms. The results also demonstrate that the robust affine decreases the absolute error compared to the classic approach and that the bone refinement process reduces the bias in the bone region. The proposed method could be used to correct for attenuation PET/MR data, but also for dosimetry calculations in the context of MR-based radiotherapy treatment planning.

  12. Effect of Scanning and Reconstruction Parameters on Three Dimensional Volume and CT Value Measurement of Pulmonary Nodules: A Phantom Study

    Directory of Open Access Journals (Sweden)

    Datong SU

    2017-08-01

    Full Text Available Background and objective The computed tomography (CT follow-up of indeterminate pulmonary nodules aiming to evaluate the change of the volume and CT value is the common strategy in clinic. The CT dose needs to considered on serious CT scans in addition to the measurement accuracy. The purpose of this study is to quantify the precision of pulmonary nodule volumetric measurement and CT value measurement with various tube currents and reconstruction algorithms in a phantom study with dual-energy CT. Methods A chest phantom containing 9 artificial spherical solid nodules with known diameter (D=2.5 mm, 5 mm, 10 mm and density (-100 HU, 60 HU and 100 HU was scanned using a 64-row detector CT canner at 120 Kilovolt & various currents (10 mA, 20 mA, 50 mA, 80 mA,100 mA, 150 mA and 350 mA. Raw data were reconstructed with filtered back projection and three levels of adaptive statistical iterative reconstruction algorithm (FBP, ASIR; 30%, 50% and 80%. Automatic volumetric measurements were performed using commercially available software. The relative volume error (RVE and the absolute attenuation error (AAE between the software measures and the reference-standard were calculated. Analyses of the variance were performed to evaluate the effect of reconstruction methods, different scan parameters, nodule size and attenuation on the RPE. Results The software substantially overestimated the very small (D=2.5 mm nodule's volume [mean RVE: (100.8%±28%] and underestimated it attenuation [mean AAE: (-756±80 HU]. The mean RVEs of nodule with diameter as 5 mm and 10 mm were small [(-0.9%±1.1% vs (0.9%±1.4%], however, the mean AAEs [(-243±26 HU vs (-129±7 HU] were large. The ANOVA analysis for repeated measurements showed that different tube current and reconstruction algorithm had no significant effect on the volumetric measurements for nodules with diameter of 5 mm and 10 mm (F=5.60, P=0.10 vs F=11.13, P=0.08, but significant effects on the measurement of CT

  13. Comparison of MR-based attenuation correction and CT-based attenuation correction of whole-body PET/MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Izquierdo-Garcia, David [Mount Sinai School of Medicine, Translational and Molecular Imaging Institute, New York, NY (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA (United States); Sawiak, Stephen J. [University of Cambridge, Wolfson Brain Imaging Centre, Cambridge (United Kingdom); Knesaurek, Karin; Machac, Joseph [Mount Sinai School of Medicine, Division of Nuclear Medicine, Department of Radiology, New York, NY (United States); Narula, Jagat [Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); Fuster, Valentin [Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); The Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid (Spain); Fayad, Zahi A. [Mount Sinai School of Medicine, Translational and Molecular Imaging Institute, New York, NY (United States); Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States)

    2014-08-15

    The objective of this study was to evaluate the performance of the built-in MR-based attenuation correction (MRAC) included in the combined whole-body Ingenuity TF PET/MR scanner and compare it to the performance of CT-based attenuation correction (CTAC) as the gold standard. Included in the study were 26 patients who underwent clinical whole-body FDG PET/CT imaging and subsequently PET/MR imaging (mean delay 100 min). Patients were separated into two groups: the alpha group (14 patients) without MR coils during PET/MR imaging and the beta group (12 patients) with MR coils present (neurovascular, spine, cardiac and torso coils). All images were coregistered to the same space (PET/MR). The two PET images from PET/MR reconstructed using MRAC and CTAC were compared by voxel-based and region-based methods (with ten regions of interest, ROIs). Lesions were also compared by an experienced clinician. Body mass index and lung density showed significant differences between the alpha and beta groups. Right and left lung densities were also significantly different within each group. The percentage differences in uptake values using MRAC in relation to those using CTAC were greater in the beta group than in the alpha group (alpha group -0.2 ± 33.6 %, R{sup 2} = 0.98, p < 0.001; beta group 10.31 ± 69.86 %, R{sup 2} = 0.97, p < 0.001). In comparison to CTAC, MRAC led to underestimation of the PET values by less than 10 % on average, although some ROIs and lesions did differ by more (including the spine, lung and heart). The beta group (imaged with coils present) showed increased overall PET quantification as well as increased variability compared to the alpha group (imaged without coils). PET data reconstructed with MRAC and CTAC showed some differences, mostly in relation to air pockets, metallic implants and attenuation differences in large bone areas (such as the pelvis and spine) due to the segmentation limitation of the MRAC method. (orig.)

  14. Mosaic pattern of lung attenuation on thin-section CT : review of 31 cases

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young Hi; An, Jee Hyun; Lee, Kye Young; Jee, Young Koo; Lee, Young Seok [Dankook Univ. College of Medicine, Choan (Korea, Republic of)

    1998-07-01

    To correlate radiologic findings with clinical findings in patients with a mosaic pattern of lung attenuation, as seen on thin-section CT. Materials and Methods : Thirty-one cases in which a mosaic pattern of lung attenuation was detected on combined expiratory and inspiratory scans of thin-section CT were retrospectively analyzed. Cases involving infiltrative lung disease were excluded. Both thin-section CT and clinical findings we reanalyzed and the relationship between the extent of the area of hyperlucency -as seen on expiratory scan- and physiologic parameters was evaluated. The subjects were 10 men and 21 women ranged in age from 25 to 76 (mean 50)years. Results : Twenty-nine patients with small airway disease, [chronic bronchitis and/or bronchiolitis(n=11),bronchiectasis(n=8), bronchial asthma(n=8), mycoplasmic pneumonitis(n=1) and hypersensitive pneumonitis(n=1),] and two patients with pulmonary vascular disease, [chronic pulmonary thromboembolism(n=1) and stenosis of the left upper pulmonary artery(n=1)] were included in our study. Commonly associated thin-section CT findings in the cases involving small airway disease(n=29) were bronchial wall thickening(n=25), nodular opacity(n=25), bronchial and bronchiolar dilatation(n=20) and small branching opacity(n=16). These findings were not observed in two patients with pulmonary vascular disease, though bronchial wall thickening was seen in the patient with chronic pulmonary thromboembolism. At expiratory scan level, there was statistical correlation between FEV1/FVC and the number of pulmonary segments(r= 0.982, p<0.05), but no correlation between FEV1/FVC and the percentage area of hyperlucency(r=0.803, p>0.05). Conclusion: The mosaic pattern of lung attenuation seen on thin-section CT is indicative of various diseases, involving small airways such as bronchiolitis, bronchitis, bronchiectasis and bronchial asthma, and vascular lung disease. Bronchial wall thickening and nodular opacity can be associated with

  15. A comparison of CT- and MR-based attenuation correction in neurological PET

    Energy Technology Data Exchange (ETDEWEB)

    Dickson, John C.; O' Meara, Celia; Barnes, Anna [University College London Hospitals, Institute of Nuclear Medicine, London (United Kingdom)

    2014-06-15

    To assess the quantitative accuracy of current MR attenuation correction (AC) methods in neurological PET, in comparison to data derived using CT AC. This retrospective study included 25 patients who were referred for a neurological FDG PET examination and were imaged sequentially by PET/CT and simultaneous PET/MR. Differences between activity concentrations derived using Dixon and ultrashort echo time (UTE) MR-based AC and those derived from CT AC were compared using volume of interest and voxel-based approaches. The same comparisons were also made using PET data represented as SUV ratios (SUVr) using grey matter cerebellum as the reference region. Extensive and statistically significant regional underestimations of activity concentrations were found with both Dixon AC (P < 0.001) and UTE AC (P < 0.001) in all brain regions when compared to CT AC. The greatest differences were found in the cortical grey matter (Dixon AC 21.3 %, UTE AC 15.7 %) and cerebellum (Dixon AC 19.8 %, UTE AC 17.3 %). The underestimation using UTE AC was significantly less than with Dixon AC (P < 0.001) in most regions. Voxel-based comparisons showed that all cortical grey matter and cerebellum uptake was underestimated with Dixon AC compared to CT AC. Using UTE AC the extent and significance of these differences were reduced. Inaccuracies in cerebellar activity concentrations led to a mixture of predominantly cortical underestimation and subcortical overestimation in SUVr PET data for both MR AC methodologies. MR-based AC results in significant underestimation of activity concentrations throughout the brain, which makes the use of SUVr data difficult. These effects limit the quantitative accuracy of neurological PET/MR. (orig.)

  16. Experimental realization of fluence field modulated CT using digital beam attenuation

    Science.gov (United States)

    Szczykutowicz, T. P.; Mistretta, C. A.

    2014-03-01

    Tailoring CT scan acquisition parameters to individual patients is a topic of much research in the CT imaging community. It is now common place to find automatically adjusted tube current options for modern CT scanners. In addition, the use of beam shaping filters, commonly called bowtie filters, is available on most CT systems and allows for different body regions to receive different incident x-ray fluence distributions. However, no method currently exists which allows for the form of the incident x-ray fluence distribution to change as a function of the view angle. This study represents the first experimental realization of fluence field modulated CT (FFMCT) for a c-arm geometry CT scan. X-ray fluence modulation is accomplished using a digital beam attenuator (DBA). The device is composed of ten iron wedge pairs that modulate the thickness of iron, the x-rays must traverse before reaching a patient. Using this device, experimental data was taken using a Siemens Zeego c-arm scanner. Scans were performed on a cylindrical polyethylene phantom and on two different sections of an anthropomorphic phantom. The DBA was used to equalize the x-ray fluence striking the detector for each scan. Non DBA, or ‘flat field’ scans were also acquired of the same phantom objects for comparison. In addition, a scan was performed in which the DBA was used to enable volume of interest (VOI) imaging. In VOI, only a small sub-volume within a patient receives full dose and the rest of the patient receives a much lower dose. Data corrections unique to using a piece-wise constant modulator were also developed. The feasibility of FFMCT implemented using a DBA device has been demonstrated. Initial results suggest dose reductions of up to 3.6 times relative to ‘flat field’ CT. In addition to dose reduction, the DBA enables a large improvement in image noise uniformity and the ability to provide regionally enhanced signal to noise using VOI imaging techniques. The results presented in

  17. Standardized perfusion value of the esophageal carcinoma and its correlation with quantitative CT perfusion parameter values

    Energy Technology Data Exchange (ETDEWEB)

    Djuric-Stefanovic, A., E-mail: avstefan@eunet.rs [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Unit of Digestive Radiology (First University Surgical Clinic), Center of Radiology and MR, Clinical Center of Serbia, Belgrade (Serbia); Saranovic, Dj., E-mail: crvzve4@gmail.com [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Unit of Digestive Radiology (First University Surgical Clinic), Center of Radiology and MR, Clinical Center of Serbia, Belgrade (Serbia); Sobic-Saranovic, D., E-mail: dsobic2@gmail.com [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Center of Nuclear Medicine, Clinical Center of Serbia, Belgrade (Serbia); Masulovic, D., E-mail: draganmasulovic@yahoo.com [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Unit of Digestive Radiology (First University Surgical Clinic), Center of Radiology and MR, Clinical Center of Serbia, Belgrade (Serbia); Artiko, V., E-mail: veraart@beotel.rs [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Center of Nuclear Medicine, Clinical Center of Serbia, Belgrade (Serbia)

    2015-03-15

    Purpose: Standardized perfusion value (SPV) is a universal indicator of tissue perfusion, normalized to the whole-body perfusion, which was proposed to simplify, unify and allow the interchangeability among the perfusion measurements and comparison between the tumor perfusion and metabolism. The aims of our study were to assess the standardized perfusion value (SPV) of the esophageal carcinoma, and its correlation with quantitative CT perfusion measurements: blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) of the same tumor volume samples, which were obtained by deconvolution-based CT perfusion analysis. Methods: Forty CT perfusion studies of the esophageal cancer were analyzed, using the commercial deconvolution-based CT perfusion software (Perfusion 3.0, GE Healthcare). The SPV of the esophageal tumor and neighboring skeletal muscle were correlated with the corresponding mean tumor and muscle quantitative CT perfusion parameter values, using Spearman's rank correlation coefficient (r{sub S}). Results: Median SPV of the esophageal carcinoma (7.1; range: 2.8–13.4) significantly differed from the SPV of the skeletal muscle (median: 1.0; range: 0.4–2.4), (Z = −5.511, p < 0.001). The cut-off value of the SPV of 2.5 enabled discrimination of esophageal cancer from the skeletal muscle with sensitivity and specificity of 100%. SPV of the esophageal carcinoma significantly correlated with corresponding tumor BF (r{sub S} = 0.484, p = 0.002), BV (r{sub S} = 0.637, p < 0.001) and PS (r{sub S} = 0.432, p = 0.005), and SPV of the skeletal muscle significantly correlated with corresponding muscle BF (r{sub S} = 0.573, p < 0.001), BV (r{sub S} = 0.849, p < 0.001) and PS (r{sub S} = 0.761, p < 0.001). Conclusions: We presented a database of the SPV for the esophageal cancer and proved that SPV of the esophageal neoplasm significantly differs from the SPV of the skeletal muscle, which represented a sample of healthy

  18. Influence of CT-based attenuation correction on dopamine transporter SPECT with [123I]FP-CIT

    OpenAIRE

    Lapa, Constantin; Spehl, Timo S; Brumberg, Joachim; Isaias, Ioannis U; Schlögl, Susanne; Lassmann, Michael; Herrmann, Ken; Philipp T. Meyer

    2015-01-01

    Dopamine transporter (DAT) imaging using single-photon emission computed tomography (SPECT) and 123I-labelled radiopharmaceuticals like [123I]FP-CIT is an established part in the diagnostic work-up of parkinsonism. Guidelines recommend attenuation correction (AC), either by a calculated uniform attenuation matrix (calAC) or by a measured attenuation map (nowadays done by low-dose CT; CTAC). We explored the impact of CTAC compared to conventional calAC on diagnostic accuracy and the use of DAT...

  19. Size-based emphysema cluster analysis on low attenuation area in 3D volumetric CT: comparison with pulmonary functional test

    Science.gov (United States)

    Lee, Minho; Kim, Namkug; Lee, Sang Min; Seo, Joon Beom; Oh, Sang Young

    2015-03-01

    To quantify low attenuation area (LAA) of emphysematous regions according to cluster size in 3D volumetric CT data of chronic obstructive pulmonary disease (COPD) patients and to compare these indices with their pulmonary functional test (PFT). Sixty patients with COPD were scanned by a more than 16-multi detector row CT scanner (Siemens Sensation 16 and 64) within 0.75mm collimation. Based on these LAA masks, a length scale analysis to estimate each emphysema LAA's size was performed as follows. At first, Gaussian low pass filter from 30mm to 1mm kernel size with 1mm interval on the mask was performed from large to small size, iteratively. Centroid voxels resistant to the each filter were selected and dilated by the size of the kernel, which was regarded as the specific size emphysema mask. The slopes of area and number of size based LAA (slope of semi-log plot) were analyzed and compared with PFT. PFT parameters including DLco, FEV1, and FEV1/FVC were significantly (all p-value< 0.002) correlated with the slopes (r-values; -0.73, 0.54, 0.69, respectively) and EI (r-values; -0.84, -0.60, -0.68, respectively). In addition, the D independently contributed regression for FEV1 and FEV1/FVC (adjust R sq. of regression study: EI only, 0.70, 0.45; EI and D, 0.71, 0.51, respectively). By the size based LAA segmentation and analysis, we evaluated the Ds of area, number, and distribution of size based LAA, which would be independent factors for predictor of PFT parameters.

  20. Quantitative imaging values of CT, MR, and FDG-PET to differentiate pineal parenchymal tumors and germinomas: are they useful?

    Energy Technology Data Exchange (ETDEWEB)

    Kakigi, Takahide; Okada, Tomohisa; Kanagaki, Mitsunori; Yamamoto, Akira; Fushimi, Yasutaka; Sakamoto, Ryo; Togashi, Kaori [Kyoto University Graduate School of Medicine, Department of Diagnostic Imaging and Nuclear Medicine, Sakyo-ku, Kyoto (Japan); Arakawa, Yoshiki; Takahashi, Jun C. [Kyoto University Graduate School of Medicine, Department of Neurosurgery, Kyoto (Japan); Mikami, Yoshiki [Kyoto University Graduate School of Medicine, Department of Pathology, Kyoto (Japan); Shimono, Taro [Osaka City University Graduate School of Medicine, Department of Radiology, Osaka (Japan)

    2014-04-15

    Quantitative values of CT attenuation, apparent diffusion coefficient (ADC), and standardized uptake value (SUV) were investigated for differentiation between pineal parenchymal tumors (PPTs) and germinomas. Differences in age, sex, and calcification pattern were also evaluated. Twenty-three patients with PPTs and germinomas in 20 years were retrospectively enrolled under the approval of the institutional review board. CT attenuation, ADC, and SUV (20, 13, and 10 patients, respectively) were statistically compared between the two tumors. Differences in sex and patterns of calcification (''exploded'' or ''engulfed'') were also examined. Mean patient ages were compared among three groups of pineoblastoma, pineal parenchymal tumor of intermediate differentiation, (PPTID) and pineocytoma and germinoma. None of the quantitative values of CT attenuation, ADC, and SUV showed significant differences between PPTs and germinomas (p >.05). However, there was a significant difference in age (p <.05) among the three groups of pineoblastoma (mean age ± standard deviation 7.0 ± 8.7 years), PPTID, and pineocytoma (53.7 ± 11.4 years) and germinoma (19.1 ± 8.1 years). Sex also showed significant differences between PPTs and germinomas (p =.039). Exploded pattern of calcification was found in 9 of 11 PPT patients and engulfed pattern in 7 of 9 patients with germinomas. No reverse pattern was observed, and the patterns of calcification were considered highly specific of tumor types. None of the quantitative imaging values could differentiate PPTs from germinomas. Age, sex, and calcification patterns were confirmed useful in differentiating these tumors to some degree. (orig.)

  1. Impact of CT and 137Cs attenuation correction on the quality and standardized uptake value of PET imaging%不同衰减校正方法及无衰减校正对PET显像结果的影响

    Institute of Scientific and Technical Information of China (English)

    黄克敏; 贺小红; 冯彦林; 温广华; 余丰文; 刘德军; 袁建伟; 杨明

    2008-01-01

    attenuation correc-tion (AC) methodology. The aim of this study was to investigate the impact to the PET image quality and standardized uptake value (SUV) with CT and 137Cs AC (CTAC and CsAC) and to compare image quality with and without AC (NOAC). Methods Jaszczak phantom with smallest inserts and 30 patients were studied on the Gemini PET/CT system. CTAC, CsAC and NOAC PET images were reconstructed respec-tively. The image special resolution, uniformity and average SUV from the phantom studies were compared. The max and rain non-uniformity ( Nui ) of each image were calculated for the uniformity regions of the phantom images with both CTAC and CSAC. Regions of interest (ROIs) of the normal soft tissue, bone, high 18F-fluorodeoxyglueose (FDG) uptake regions and the basic remains were drawn, then the ROIs and image quality from the CTAC images were compared with those of the CsAC images. SPSS 12.0 was used for the paired t-test and Pearson analysis. Results There was no obviously difference of image spatial resolu-tion found between the CTAC and CsAC phantom studies. The image uniformity of the CTAC images was better than that of the CsAC ones [Nut values were (19±1) %-(23±2)%, (23±2)%-(29±3)% re-spectively], although the average SUVs had no statistical difference [(0.9±0.1) vs (1.0±0.1);t=0.367, P=0.719]. For the patient studies, SUV also showed no statistical difference between the CTAC and CsAC methods, in the normal tissues and high 11F-FDG uptake regions[(0.71±0.20) vs (0.75±0.23), t=-2.159, P=0.054;(5.50±4.80) vs (5.70±5.00), t=-2. 032, P=0.054]. The aver-age SUVs of CTAC images was objectively higher than that of the CsAC ones in bone and high density re-gions [(1.37±0.29) vs (1.18±0.36), t =7.960, P=0.001;(1.82±0.62) vs (0.92±0.20), t=3.451, P=0.018]. There was no significant difference in the image quality found in normal soft tissue, bone and high FDG uptake regions between CTAC and CsAC. Imaging artifacts were found only in the high density regions

  2. A novel method for incorporating respiratory-matched attenuation correction in the motion correction of cardiac PET-CT studies

    Science.gov (United States)

    McQuaid, Sarah J.; Lambrou, Tryphon; Hutton, Brian F.

    2011-05-01

    Mismatches between PET and CT datasets due to respiratory effects can lead to artefactual perfusion defects. To overcome this, we have proposed a method of aligning a single CT with each frame of a gated PET study in a semi-automatic manner, incorporating a statistical shape model of the diaphragm and a rigid registration of the heart. This ensures that the structures that could influence the appearance of the reconstructed cardiac activity are correctly matched between emission and transmission datasets. When tested on two patient studies, it was found in both cases that attenuation correction using the proposed technique resulted in PET images that were closer to the gold standard of attenuation correction with a gated CT, compared with scenarios where only heart matching was considered (and not the diaphragm) or where no transformation was performed (i.e. where a single CT frame was used to attenuation-correct all PET frames). These preliminary results suggest that diaphragm matching between PET and CT improves the quantitative accuracy of reconstructed PET images and that the proposed method of using a statistical shape model to describe the diaphragm shape and motion, in combination with a rigid registration to determine respiratory-induced heart motion, is a feasible method of achieving this.

  3. The effect of late-phase contrast enhancement on semi-automatic software measurements of CT attenuation and volume of part-solid nodules in lung adenocarcinomas

    NARCIS (Netherlands)

    Cohen, J.G.; Goo, J.M.; Yoo, R.E.; Park, S.B.; Ginneken, B. van; Ferretti, G.R.; Lee, C.H.; Park, C.M.

    2016-01-01

    OBJECTIVES: To evaluate the differences in semi-automatic measurements of CT attenuation and volume of part-solid nodules (PSNs) between unenhanced and enhanced CT scans. MATERIALS AND METHODS: CT scans including unenhanced and enhanced phases (slice thickness 0.625 and 1.25mm, respectively) for 53

  4. Reduction of dental filling metallic artifacts in CT-based attenuation correction of PET data using weighted virtual sinograms optimized by a genetic algorithm

    NARCIS (Netherlands)

    Abdoli, Mehrsima; Ay, Mohammad Reza; Ahmadian, Alireza; Dierckx, Rudi A. J. O.; Zaidi, Habib

    2010-01-01

    Purpose: The presence of metallic dental fillings is prevalent in head and neck PET/CT imaging and generates bright and dark streaking artifacts in reconstructed CT images. The resulting artifacts would propagate to the corresponding PET images following CT-based attenuation correction (CTAC). This

  5. Positive predictive value for polyps detected at screening CT colonography

    Energy Technology Data Exchange (ETDEWEB)

    Pickhardt, Perry J.; Wise, Steven M.; Kim, David H. [University of Wisconsin School of Medicine and Public Health, Department of Radiology, Madison, WI (United States)

    2010-07-15

    To determine the positive predictive value (PPV) for polyps detected at CT colonography (CTC). Assessment of 739 colorectal lesions {>=}6 mm detected prospectively at CTC screening in 479 patients was performed. By-polyp PPV was analyzed according to small (6-9 mm) versus large ({>=}10 mm) size; morphology (sessile/pedunculated/flat); diagnostic confidence level (3 = most confident, 1 = least confident); and histology. By-patient PPV was analyzed at various polyp size thresholds. By-polyp PPV for CTC-detected lesions {>=}6 mm, 6-9 mm, and {>=}10 mm was 91.6% (677/739), 90.1% (410/451), and 92.7% (267/288), respectively (p = 0.4). By-polyp PPV according to sessile, pedunculated, flat, and mass-like morphology was 92.5% (441/477), 96.5% (139/144), 77.7% (73/94), and 97.6% (40/41), respectively (p < 0.0001 for flat versus polypoid morphology). By-polyp PPV according to diagnostic confidence level was 94.7% (554/585) for highest (= level 3), 83.5% (106/127) for intermediate (= level 2), and 63.0% (17/27) for lowest (= level 1) confidence (p < 0.0001 for levels-2/3 versus level-1). By-patient PPV at 6-mm, 8-mm, 10-mm, and 30-mm polyp size thresholds was 92.3% (442/479), 93.0% (306/329), 93.1% (228/245), and 97.4% (38/39), respectively. The overall per-polyp and per-patient PPV for lesions {>=}6 mm was 92% for CTC screening. Increased diagnostic confidence and polypoid (non-flat) morphology correlated with a higher PPV, whereas small versus large polyp size had very little effect. (orig.)

  6. The value of CT in detecting pathologic bowel perforation

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jong Wun; Shin, Joo Yong; Kim, Hong; Rhee, Chang Soo; Lee, Sung Moon; Joo, Yang Goo; Suh, Soo Jhi [Keimyung Univ. School of Medicine, Taegu (Korea, Republic of)

    1997-10-01

    To evaluate the usefulness of CT for assessing the location and cause of pathologic gastrointestinal perforation. A retrospective analysis of abdominal CT was performed in 27 perforations of 26 patients with underlying gastrointestinal pathology. Fifteen benign and 12 malignant perforations consisted of five gastric cancers, one gastric ulcer, ten duodenal bulb ulcers. two bowel adhesions, one jejunal metastasis from lung cancer, one ileocolic Crohn's disease, one radiation colitis and six colon cancers. CT scans were evaluated for (1) diagnosis of bowel perforation, (2) assessment of the cause and site of perforation, and, in particular, differentiation between benignancy and malignancy, and (3) complications and their extent. CT easily detected varying amounts of free air or fluid collection, and infiltration or abscess formation adjacent to the main lesion, and the diagnosis of gastrointestinal perforation was therefore easy. In 11 of the 12 malignancies (92%), primary tumor was diagnosed, but detection of the site of perforation was possible in only seven cases(7/12, 58%). The 15 benign lesions revealed nonspecific CT findings, and the perforation site could be presumed in six (6/15, 40%). In one case of Crohn's disease, the primary cause was visualized. Among six colonic cancers, four pericolic abscesses and two fistulas to adjacent organs were found, but there was no evidence of diffuse peritonitis. CT was helpful to lead to optimal treatment of pathologic gastrointestinal On CT the detectability of perforation, primary benign or malignant lesion, perforation site and extent of complication was high, and this modality was therefore a useful indicator of the optimal treatment for pathologic gastrointestinal perforations.=20.

  7. Value of abdominal CT in the emergency department for patients with abdominal pain

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, Max P.; Siewert, Bettina; Bromberg, Rebecca; Raptopoulos, Vassilios [Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215 (United States); Sands, Daniel Z. [Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215 (United States); Edlow, Jonathan [Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215 (United States)

    2003-02-01

    The purpose of our study is to demonstrate the value of CT in the emergency department (ED) for patients with non-traumatic abdominal pain. Between August 1998 and April 1999, 536 consecutive patients with non-traumatic abdominal pain were entered into our study. Using a computer order entry system, physicians were asked to identify: (a) their most likely diagnosis; (b) their level of certainty in their diagnosis; (c) if they thought CT would be normal or abnormal; (d) their treatment plan (prior to knowledge of the CT results); and (e) their role in deciding to order CT. This information was correlated with each patient's post-CT diagnosis and subsequent management. Pre- and post-CT diagnoses were concordant in 200 of 536 (37%) patients. The physicians' certainty in the accuracy of their pre-CT diagnosis was less than high in 88% of patients. Prior to CT, the management plan included hospital admission for 402 patients. Following CT, only 312 patients were actually admitted; thus, the net impact of performing CT was to obviate the need for hospital admission in 90 of 536 (17%) of patients with abdominal pain. Prior to CT, 67 of 536 (13%) of all patients would have undergone immediate surgery; however, following CT only 25 (5%) actually required immediate surgery. Among patients with the four most common pre-CT diagnoses (appendicitis, abscess, diverticulitis, and urinary tract stones) CT had the greatest impact on hospital admission and surgical management for patients with suspected appendicitis. For patients with suspected appendicitis, CT reduced the hospital admission rate in 28% (26 of 91) of patients and changed the surgical management in 40% (39 of 91) of patients. Our study demonstrates the advantage of performing abdominal CT in the ED for patients with non-traumatic abdominal pain. (orig.)

  8. The value of SPET/CT in chronic osteomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Horger, Marius; Pfannenberg, Christina; Dammann, Florian; Claussen, Claus D. [Department of Diagnostic Radiology, Eberhard-Karls Universitaet, Hoppe-Seyler-Str. 3, 72076, Tuebingen (Germany); Eschmann, Susanne Martina; Bares, Roland [Department of Nuclear Medicine, Eberhard-Karls-Universitaet, Tuebingen (Germany); Storek, Dieter [Department of Traumatology and Orthopaedic Surgery, Eberhard-Karls-Universitaet, Tuebingen (Germany); Vonthein, Reinhard [Department of Medical Biometry, Eberhard-Karls-Universitaet, Tuebingen (Germany)

    2003-12-01

    Immunoscintigraphy with technetium-99m labelled anti-granulocyte antibodies (AGA) is an equivalent technique to imaging with in vitro-labelled leucocytes, which is now considered state of the art in the diagnostic work-up of patients with suspected post-traumatic chronic osteomyelitis. In this study, we evaluated the use of a combined single-photon emission tomography/computed tomography (SPET/CT) device to improve detection and anatomical definition of inflammatory bone lesions. Twenty-seven patients with 29 sites of suspected bone infection underwent immunoscintigraphy with 750 MBq {sup 99m}Tc-labelled AGA. Planar scans were acquired immediately, 4 h and 24 h after injection, and combined SPET/CT was performed using a dual-head multifunctional gamma camera equipped with a low-power X-ray system. Accumulation of AGA in inflammatory lesions was quantitated, comparing uptake at 4 and 24 h after injection. The validation was based on culture data derived from surgical or biopsy samples (20 lesions in 18 patients) or clinical follow-up without further therapy for more than 6 months (nine lesions). On a lesion-by-lesion basis 19 true positive, one false positive and nine true negative findings were obtained. SPET/CT correctly identified the location of all positive foci in the appendicular skeleton and that of a cold lesion in the axial skeleton. It also enabled differentiation between soft tissue infection, septic arthritis and osteomyelitis, as well as between cortical, corticomedullary and subperiosteal foci. Sensitivity was identical for SPET and SPET/CT (100%), whereas specificity was improved from 78% to 89% by the use of SPET/CT. Combined SPET/CT improves the accuracy of immunoscintigraphy by allowing correct differentiation between soft tissue infection and bone involvement. This technique may gain clinical relevance in the selection of patients for surgical therapy. (orig.)

  9. The effect of different chemoembolization materials on CT-based attenuation correction in PET/CT; Effekt verschiedener Chemoembolisationsmaterialien auf die CT-basierte Schwaechungskorrektur der PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Heusner, T.A.; Fronz, U.; Verhagen, R.; Forsting, M.; Antoch, G. [Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie, Universitaetsklinik Essen (Germany); Jentzen, W.; Bockisch, A. [Klinik fuer Nuklearmedizin, Universitaetsklinik Essen (Germany)

    2007-11-15

    Purpose: Primary and secondary hypervascularized liver tumors may be treated with transarterial chemoembolization (TACE). The purpose of this study was to experimentally quantify the effect of different chemoembolization materials on the PET activity concentration in PET/CT. Materials and methods: Different concentrations of lipiodol, tungsten, tantalum, and a different number of platinum coils embedded in a carrier substance were placed in a liver phantom. An insert filled with only the carrier substance served as the negative control. The liver phantom was placed in a body phantom. The liver phantom was filled with 63.3 KBq [18-F]-Fluor-2-deoxy-D-glucose (FDG)/ml water, the body phantom was filled with 19.7 KBq FDG/ml water. PET/CT was performed and PET attenuation correction was performed based on the CT data. We defined: Activity concentration over embolization material (kBq/ml) {approx} measured activity concentration; activity concentration over negative control (kBq/ml) {approx} real activity concentration. An overestimation of the activity concentration was quantified by the following ratio: Activity concentration overestimation = activity concentration over embolization material (kBq/ml)/activity concentration over negative control (kBq/ml). Results: All chemoembolization materials led to an overestimation of the PET activity concentration when using CT information for PET attenuation correction. The extent of overestimation is dependent on the concentration and the density of the chemoembolizing agent. PET activity overestimation was 11 - 151% with lipiodol, 34 - 1827% with tungsten, 16 - 1205% with tantalum, and 4 - 29% with platinum coils. (orig.)

  10. Value of early follow-up CT in paediatric tuberculous meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Andronikou, Savvas [University of Cape Town, Department of Radiology, Cape Town (South Africa); Wieselthaler, Nicky; Smith, Bruce; Douis, Hassan [Red Cross Children' s Hospital, Department of Paediatric Radiology, School of Child and Adolescent Health, Cape Town (South Africa); Fieggen, A. Graham; Toorn, Ronald van; Wilmshurst, Jo [Red Cross Children' s Hospital, Department of Paediatric Radiology, School of Child and Adolescent Health, Cape Town (South Africa); Red Cross Children' s Hospital, Department of Neurosciences, School of Child and Adolescent Health, Cape Town (South Africa)

    2005-11-01

    The value of CT in the diagnosis of tuberculous meningitis (TBM) in children is well reported. Follow-up CT scanning for these patients is, however, not well described and, in particular, the value of early follow-up CT has not been addressed for children with TBM. To assess the value of early follow-up CT in children with TBM in identifying diagnostic, prognostic and therapeutically relevant features of TBM. A retrospective 4-year review of CT scans performed within 1 week and 1 month of initial CT in children with proven (CSF culture-positive) and probable TBM (CSF profile-positive but culture-negative) and comparison with initial CT for the diagnostic, prognostic and therapeutic CT features of TBM. The CT scans of 50 children were included (19 ''definite'' TBM; 31 ''probable'' TBM). Of these, 30 had CT scans performed within 1 week of the initial CT. On initial CT, 44 patients had basal enhancement. Only 24 patients had contrast medium-enhanced follow-up scans. Important findings include: 8 of 29 patients (who were not shunted) developed new hydrocephalus. New infarcts developed in 24 patients; 45% of those who did not have infarction initially developed new infarcts. Three of the six patients who did not show basal enhancement on initial scans developed this on the follow-up scans, while in seven patients with pre-existing basal enhancement this became more pronounced. Two patients developed hyperdensity in the cisterns on non-contrast medium scans. Eight patients developed a diagnostic triad of features. Three patients developed CT features of TBM where there was none on the initial scans. Early follow-up CT is useful in making a diagnosis of TBM by demonstrating features that were not present initially and by demonstrating more sensitive, obvious or additional features of TBM. In addition, follow-up CT is valuable as a prognostic indicator as it demonstrates additional infarcts which may have developed or become more

  11. Value of postmortem thoracic CT over radiography in imaging of pediatric rib fractures

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Terence S.; Babyn, Paul S. [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto (Canada); Reyes, Jeanette A.; Chiasson, David A. [The Hospital for Sick Children, Department of Paediatric Laboratory Medicine, Toronto (Canada); Moineddin, Rahim [University of Toronto, Department of Family and Community Medicine, Toronto (Canada); Berdon, Walter E. [Columbia Presbyterian Medical Center, Babies Hospital, Department of Radiology, New York, NY (United States)

    2011-06-15

    Studies have reported that thoracic CT may provide greater sensitivity compared with radiography in detection of pediatric rib fractures and fracture healing. The additional sensitivity afforded by thoracic CT may have medicolegal implications where abuse is suspected. To determine the additional value of postmortem thoracic CT compared with radiography in detecting pediatric rib fractures, and fracture healing, using autopsy findings as a gold standard. We retrospectively reviewed 56 coroner's cases with postmortem radiography and CT thoracic survey. All studies underwent primary interpretation by one or two radiologists. The study radiologist independently reviewed all images from 13 patients with positive findings on radiography, CT or autopsy. Sensitivity and specificity between observers and imaging modalities were compared. Primary interpretation: Fractures were recognized on radiography in 5/12 patients who had fractures found at autopsy, and on CT in 8/12 patients. In total, 29% (24/83) of fractures were reported on radiography, and 51% (52/101) of fractures were reported on CT. Study radiologist: Fractures were recognized on radiography in 7/12 patients who had fractures found at autopsy, and on CT in 11/12 patients. In total, 46% (38/83) of fractures were reported on radiography, and 85% (86/101) of fractures were reported on CT. Postmortem thoracic CT provides greater sensitivity than radiography in detecting pediatric rib fractures, most notably in anterior and posterior fractures. However, the degree of improvement in sensitivity provided by CT might depend on observer experience. (orig.)

  12. The diagnostic value of PET/CT scanning in patients with cervical cancer

    DEFF Research Database (Denmark)

    Loft, Annika; Berthelsen, Anne Kiil; Roed, Henrik

    2007-01-01

    OBJECTIVE: To investigate the clinical value of PET/CT as a supplement to FIGO staging in patients with cervical cancer stage >or=1B. METHODS: This prospective study included 120 consecutive patients. After staging, a whole-body PET/CT scan was performed and these examinations were divided into two....../CT scanning for newly diagnosed cervical cancer FIGO stage >or=1B has a high sensitivity and specificity, and can be a valuable supplement to the FIGO staging procedure....

  13. Diagnostic value of quantitative stenosis predictors with coronary CT angiography compared to invasive fractional flow reserve

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Rui [Heart & Vascular Center, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Drive Charleston, SC 29425-2260 (United States); Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Renker, Matthias [Heart & Vascular Center, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Drive Charleston, SC 29425-2260 (United States); Kerckhoff Heart and Thorax Center, Benekestrasse 2-8, 61231 Bad Nauheim (Germany); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Heart & Vascular Center, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Drive Charleston, SC 29425-2260 (United States); Wichmann, Julian L. [Heart & Vascular Center, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Drive Charleston, SC 29425-2260 (United States); Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Fuller, Stephen R.; Rier, Jeremy D.; Bayer, Richard R.; Steinberg, Daniel H. [Heart & Vascular Center, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Drive Charleston, SC 29425-2260 (United States); De Cecco, Carlo N. [Heart & Vascular Center, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Drive Charleston, SC 29425-2260 (United States); Departments of Radiological Sciences, Oncology, and Pathology, University of Rome “Sapienza”-Polo Pontino, Latina, Viale Regina Elena, 324-00161 Roma (Italy); Baumann, Stefan [Heart & Vascular Center, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Drive Charleston, SC 29425-2260 (United States); First Department of Medicine, University Medical Centre Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim (Germany)

    2015-08-15

    Highlights: • Evaluation of the diagnostic performance of CCTA predictors for coronary stenosis. • TAG was unable to detect hemodynamically significant coronary lesions. • CT-FFR, LL/MLD{sup 4} and CCO provide enhanced diagnostic performance over CCTA. • CT-FFR was the best parameter. - Abstract: Objective: To evaluate the diagnostic performance of CCTA-derived stenosis predictors including CT-FFR for the detection of ischemia-inducing stenosis compared to invasive FFR. Materials and methods: Stenosis parameters were assessed using dual-source CT (DSCT). All patients underwent both CCTA and invasive FFR within 3 months and were retrospectively analyzed. Observers visually assessed all CCTA studies and performed multiple lesion measurements. Lesion length/minimal luminal diameter{sup 4} (LL/MLD{sup 4}), transluminal attenuation gradient (TAG), corrected coronary attenuation (CCO) and CT-FFR were calculated. Results: The cohort included 32 patients (58 ± 12 years, 66%male). Among 32 coronary lesions, 8 (25%) were considered hemodynamically significant with an FFR <0.80. Compared to invasive FFR, the per-vessel sensitivity and specificity of CCTA, CT-FFR, LL/MLD{sup 4}, CCO and TAG for detecting hemodynamically significant lesions were 100% and 54%, 100% and 91%, 85% and 92%, 66% and 88%, 37% and 58%, respectively. Receiver operating characteristics analysis resulted in an area under the curve of 0.91 for CT-FFR (p = 0.0005), 0.88 for LL/MLD{sup 4} (p < 0.0001), 0.85 for CCO (p < 0.0001). TAG with an AUC of 0.67 (p = 0.152) was unable to discriminate between vessels with or without hemodynamically significant lesions. Conclusion: CT-FFR, LL/MLD{sup 4} and CCO provide enhanced diagnostic performance over CCTA analysis alone for discrimination of hemodynamically significant coronary stenosis.

  14. A new technique to characterize CT scanner bow-tie filter attenuation and applications in human cadaver dosimetry simulations.

    Science.gov (United States)

    Li, Xinhua; Shi, Jim Q; Zhang, Da; Singh, Sarabjeet; Padole, Atul; Otrakji, Alexi; Kalra, Mannudeep K; Xu, X George; Liu, Bob

    2015-11-01

    To present a noninvasive technique for directly measuring the CT bow-tie filter attenuation with a linear array x-ray detector. A scintillator based x-ray detector of 384 pixels, 307 mm active length, and fast data acquisition (model X-Scan 0.8c4-307, Detection Technology, FI-91100 Ii, Finland) was used to simultaneously detect radiation levels across a scan field-of-view. The sampling time was as short as 0.24 ms. To measure the body bow-tie attenuation on a GE Lightspeed Pro 16 CT scanner, the x-ray tube was parked at the 12 o'clock position, and the detector was centered in the scan field at the isocenter height. Two radiation exposures were made with and without the bow-tie in the beam path. Each readout signal was corrected for the detector background offset and signal-level related nonlinear gain, and the ratio of the two exposures gave the bow-tie attenuation. The results were used in the geant4 based simulations of the point doses measured using six thimble chambers placed in a human cadaver with abdomen/pelvis CT scans at 100 or 120 kV, helical pitch at 1.375, constant or variable tube current, and distinct x-ray tube starting angles. Absolute attenuation was measured with the body bow-tie scanned at 80-140 kV. For 24 doses measured in six organs of the cadaver, the median or maximum difference between the simulation results and the measurements on the CT scanner was 8.9% or 25.9%, respectively. The described method allows fast and accurate bow-tie filter characterization.

  15. A new technique to characterize CT scanner bow-tie filter attenuation and applications in human cadaver dosimetry simulations

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xinhua; Shi, Jim Q.; Zhang, Da; Singh, Sarabjeet; Padole, Atul; Otrakji, Alexi; Kalra, Mannudeep K.; Liu, Bob, E-mail: bliu7@mgh.harvard.edu [Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Xu, X. George [Nuclear Engineering Program, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2015-11-15

    Purpose: To present a noninvasive technique for directly measuring the CT bow-tie filter attenuation with a linear array x-ray detector. Methods: A scintillator based x-ray detector of 384 pixels, 307 mm active length, and fast data acquisition (model X-Scan 0.8c4-307, Detection Technology, FI-91100 Ii, Finland) was used to simultaneously detect radiation levels across a scan field-of-view. The sampling time was as short as 0.24 ms. To measure the body bow-tie attenuation on a GE Lightspeed Pro 16 CT scanner, the x-ray tube was parked at the 12 o’clock position, and the detector was centered in the scan field at the isocenter height. Two radiation exposures were made with and without the bow-tie in the beam path. Each readout signal was corrected for the detector background offset and signal-level related nonlinear gain, and the ratio of the two exposures gave the bow-tie attenuation. The results were used in the GEANT4 based simulations of the point doses measured using six thimble chambers placed in a human cadaver with abdomen/pelvis CT scans at 100 or 120 kV, helical pitch at 1.375, constant or variable tube current, and distinct x-ray tube starting angles. Results: Absolute attenuation was measured with the body bow-tie scanned at 80–140 kV. For 24 doses measured in six organs of the cadaver, the median or maximum difference between the simulation results and the measurements on the CT scanner was 8.9% or 25.9%, respectively. Conclusions: The described method allows fast and accurate bow-tie filter characterization.

  16. The value of precontrast thoraco-abdominopelvic CT in polytrauma patients

    Energy Technology Data Exchange (ETDEWEB)

    Esposito, A.A., E-mail: rxandreaesposito@yahoo.it [Department of Radiology, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20121 Milan (Italy); Zilocchi, M., E-mail: massimo.zilocchi@gmail.com [Department of Radiology, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20121 Milan (Italy); Fasani, P., E-mail: fasapier65@gmail.com [Department of Radiology, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20121 Milan (Italy); Giannitto, C., E-mail: caterina.giannitto@gmail.com [School of Radiology, University of Milan, Via A. di Rudinì 8, Milan (Italy); Maccagnoni, S., E-mail: maccagnnisara@libero.it [School of Radiology, University of Milan, Via A. di Rudinì 8, Milan (Italy); Maniglio, M., E-mail: marinamaniglio@gmail.com [School of Radiology, University of Milan, Via A. di Rudinì 8, Milan (Italy); Campoleoni, M., E-mail: campoleoni@policlinico.mi.it [Medical Phisic Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Via Francesco Sforza, 35, 20121 Milan (Italy); Brambilla, R., E-mail: roberto.brambilla@policlinico.mi.it [Medical Phisic Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Via Francesco Sforza, 35, 20121 Milan (Italy); Casiraghi, E., E-mail: casiraghi@di.unimi.it [Computer Science Department, University of Milan, Via Comelico 39, Milan (Italy); Biondetti, P.R., E-mail: pibionde@tin.it [Department of Radiology, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20121 Milan (Italy)

    2015-06-15

    Highlights: • We evaluated the additional value of precontrast CT in polytrauma patient. • We evaluated the radiation dose CT in polytrauma patient. • Precontrast CT scan does not have an additional value in polytrauma patient. • Precontrast CT expose patient to an unjustified radiation dose. - Abstract: Purpose: To evaluate the utility and radiation dose of thoraco-abdominopelvic precontrast CT in polytrauma patients. Materials and methods: We examined retrospectively 125 patients who underwent a thoraco-abdominopelvic CT for trauma. Two radiologists, independently, evaluated precontrast CT acquisition and two other radiologists examined the contrast-enhanced scans. A further two radiologists assessed both the acquisitions. Mean value of sensitivity (SE), specificity (SP), positive predictive value (PPV) and negative predictive value (NPV) were calculated by each group of radiologists. For 104 patients, CTDIvol, DLP data and individual mean size were collected to calculate effective dose. Results: Mean values of SE, SP, PPV and NPV of findings of radiologists who assessed contrast-enhanced acquisitions were respectively: SE = 85%, SP = 98%, PPV = 86%, NPV = 88% versus: SE = 43%, SP = 95%, PPV = 69%, NPV = 88% of radiologists who examined non-contrast-enhanced scans. Mean values of radiologists who analyzed both acquisitions were: SE = 80%, SP = 97%, PPV = 80%, NPV = 88%. Neither the precontrast scans nor the precontrast and postcontrast scans together provided additional useful information compared to the single contrast-enhanced acquisition. Patients received a mean dose of 12 mSv for the precontrast CT. Conclusions: Precontrast CT acquisition did not provide significant information in trauma patients, exposing them to an unjustified radiation dose.

  17. Automated attenuation-based tube voltage selection for body CTA: Performance evaluation of 192-slice dual-source CT

    Energy Technology Data Exchange (ETDEWEB)

    Winklehner, Anna; Gordic, Sonja; Lauk, Eliane; Frauenfelder, Thomas; Alkadhi, Hatem; Husarik, Daniela B. [University Hospital Zurich, Institute for Diagnostic and Interventional Radiology, Zurich (Switzerland); Leschka, Sebastian [University Hospital Zurich, Institute for Diagnostic and Interventional Radiology, Zurich (Switzerland); Division of Radiology and Nuclear Medicine, St. Gallen (Switzerland)

    2015-08-15

    To assess radiation dose and image quality in body CT-angiography (CTA) with automated attenuation-based tube voltage selection (ATVS) on a 192-slice dual-source CT (DSCT). Forty patients (69.5 ± 9.6 years) who had undergone body CTA with ATVS (ref.kVp 100, ref.mAs 90) using a 2x192-slice CT in single-source mode were retrospectively included. All patients had undergone prior CTA with a 2x128-slice CT and ATVS with identical imaging and contrast media protocols, serving for comparison. Images were reconstructed with iterative reconstruction at similar strength levels. Radiation dose was determined. Image quality was assessed semi-quantitatively (1:excellent, 5:non-diagnostic), aortic attenuation, noise and CNR were determined. As compared to 128-slice DSCT, 192-slice DSCT selected tube voltages were lower in 30 patients (75 %), higher in 3 (7.5 %), and similar in 7 patients (17.5 %). CTDI{sub vol} was lower with 192-slice DSCT (4.7 ± 1.9 mGy vs. 5.8 ± 2.1 mGy; p < 0.001). Subjective image quality, mean aortic attenuation (342 ± 67HU vs. 268 ± 67HU) and CNR (9.8 ± 2.5 vs. 8.2 ± 2.9) were higher with 192-slice DSCT (all p < 0.01), all datasets being diagnostic. Our study suggests that ATVS of 192-slice DSCT for body CTA is associated with an improved image quality and further radiation dose reduction of 19 % compared to 128-slice DSCT. (orig.)

  18. The value of CT diagnosis of hernia recurrence after prosthetic repair of ventral incisional hernias

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez de la Pena, C. [Department of Surgery, Jerez General Hospital, Jerez de la Frontera (Spain); Vargas Romero, J.; Dieguez Garcia, J.A. [Department of Radiology, Jerez General Hospital, Jerez de la Frontera (Spain)

    2001-07-01

    Herein we present a prospective study made to compare the diagnostic value of a physical examination and a CT scan in the detection of a hernia relapse after carrying out of a intraperitoneal hernioplasty using a non-resorbable mesh. Fifty patients operated on for intraperitoneal hernioplasty with ePTFE mesh and postoperative symptomatology were assessed within a year of the operation via a physical exploration and CT. Each of the patients was subjected to an exploratory laparoscopy for the purpose of confirming the diagnosis. The data were analysed statistically using a chi-square test, sensitivity, specificity, confidence limits, positive predictive value, and negative predictive value. The hernia relapse was correctly diagnosed in 98% of cases by CT and in 88% of cases in the physical examination. The sensitivity was 1 in the CT examination and 0.75 in the physical examination, and the specificity results were 0.97 and 0.90, respectively. The positive predictive value in the CT exam was 0.88, whereas in the physical examination it was 0.60. The negative predictive values were 1 and 0.95, respectively. The differences between the values of both methods held a statistical meaning (chi-square test; p<0.05). The postoperative assessment by CT of symptomatic patients who have been operated on for an intraperitoneal hernioplasty with unabsorbable mesh facilitates carrying out a correct diagnosis in the detection or exclusion of hernial relapse. (orig.)

  19. Examination of image information on dental application. Extraction and significance of CT values for the teeth

    Energy Technology Data Exchange (ETDEWEB)

    Handa, Kazuko

    1988-06-01

    The first molar tooth of the mandibule from 11 volunteers was used to determine computed tomography (CT) values in the enamel, dentine, cement, pulp cavity, and root canal. Peak CT values were 1776 for the enamel, 1525 for the dentine, 1342 for the cement, 1275 for the pulp cavity, and 1318 for the root canal. Average CT values were 1730 for the enamel, 1461 for the dentine, 1305 for the cement, 1290 for the pulp cavity, and 1297 for the root canal. When calculating CT values from 10 longitudinal images and 10 or more transverse images, the values were 1843 for the enamel, 1516 for the dentine, 1292 for the cement, 942 for the pulp cavity, and 1116 for the root canal. Ten-slice images provided more definitive discrimination of the test materials when compared with peak and average CT values. Three-dimensional CT images in 10 slices may provide visual demonstration of each tissue in the teeth. (Namekawa, K.) 61 refs.

  20. Value of CT scan in the diagnosis of primary large bowel lymphoma

    Institute of Scientific and Technical Information of China (English)

    赵修义; 张雪林; 王劲; 郑卫权; 文戈

    2003-01-01

    Objective:To study the CT imaging of primary large bowel lymphoma and evaluate the value of CT scan.Methods:CT reports of 8 patients with proven primary large bowel lymphoma were retrospectively reviewed.Plain CT scans were done on all patients,enhanced CT scans simultaneously with 5 - 10 mm section thickness,and 5 - 10 mm table increments in 6 cases.Results:Primary involved sites were on the cecum(n = 3),the ascending colon(n = 2),and the rectum(n = 1).The tumor was found in multiple areas of the large bowel in 2 cases.CT appearance fell into 3 typical patterns in our study.The first was focal mass type in 2 cases,with one combined with intussusception and retroperitoneal adenopathy; the second was segmental annular involvement type in 3 cases,with one of them combined with mesenteric adenopathy; the last was diffuse involvement type in 2 cases.Multiple nodules were seen in the rectum in 1 case.Conclusion:CT was found to be accurate in detecting the primary sites and complications of lymphoma,and evaluating invasion of adjacent structures; Focal mass type,segmental annular involvement type and diffuse involvement type are the main patterns of CT features in the primary large bowel lymphoma; The features revealed by CT scan are suggestive of primary large bowel lymphoma in some cases.

  1. The Effect of Patient Age on Standardized Uptake Value-Hounsfield Unit Values of Male Genitourinery Structures In F-18 FDG PET/CT

    Directory of Open Access Journals (Sweden)

    Berrin Çavuşoğlu

    2011-12-01

    Full Text Available Objective: Relation between patient age and Hounsfield Unit (HU,which is the linear attenuation coefficient, and Standardized Uptake Values (SUV which is the amount of 18F-fluorodeoxyglucose (F-18 FDG uptake, measured in the areas of interest drawn to prostate, seminal vesicles and testicles in F-18 FDG Positron Emission Tomography/Computed Tomography (PET/CT images was investigated. Material and Methods: Mean and maximum SUV and HU values were recorded from the areas of interest (min 12 mm in diameter which showed FDG uptake in prostate, seminal vesicles and testicles from F-18 FDG PET-CT images of 21 male patients under 40 years without genitourinary cancer. The effect of patient age to SUV and HU values was examined with Pearson correlation test using SPSS program. Results: There was a negative insignificant correlation between patient age and SUV and HU values for prostate. For seminal vesicles, correlation between patient age and SUV values and HUmax were positive but insignificant, while correlation with HUmean was significant (r=0.459, p=0.00. Correlation between patient age and SUVmax and SUVmean values were significant for testicles (r=0.506, p=0.002 and r=0.467, p=0.005, respectively but the correlation between patient age and HUmax and HUmean values was not significant. Conclusion: F-18 FDG uptake in testicles in males increases with age until 40, suggesting an increase in metabolic rate. The significant correlation between age and mean HU values is probably caused by thickening of the tissue without an increase in glucose metabolism in seminal vesicles. In prostate, the effect of patient age to SUV and HU values was not observed until the age 40. (MIRT 2011;20:104-107

  2. Prognostic value of tumor necrosis at CT in diffuse large B-cell lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Hugo J.A., E-mail: h.j.a.adams@gmail.com [Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Utrecht (Netherlands); Klerk, John M.H. de [Department of Nuclear Medicine, Meander Medical Center, Amersfoort (Netherlands); Fijnheer, Rob [Department of Hematology, Meander Medical Center, Amersfoort (Netherlands); Dubois, Stefan V. [Department of Pathology, Meander Medical Center, Amersfoort (Netherlands); Nievelstein, Rutger A.J.; Kwee, Thomas C. [Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Utrecht (Netherlands)

    2015-03-15

    Highlights: •CT is compulsory for staging newly diagnosed DLBCL. •Approximately 13.7% of DLBCL patients have tumor necrosis at CT. •Tumor necrosis status at CT is not associated with any NCCN-IPI factor. •Patients with tumor necrosis at CT have a significantly worse outcome. -- Abstract: Objective: To determine the prognostic value of tumor necrosis at computed tomography (CT) in newly diagnosed diffuse large B-cell lymphoma (DLBCL). Materials and methods: This retrospective study included 51 patients with newly diagnosed DLBCL who had undergone both unenhanced and intravenous contrast-enhanced CT before R-CHOP (rituximab, cyclophosphamide, hydroxydaunorubicin, oncovin and prednisolone) chemo-immunotherapy. Presence of tumor necrosis was visually and quantitatively assessed at CT. Associations between tumor necrosis status at CT and the National Comprehensive Cancer Network (NCCN) International Prognostic Index (IPI) factors were assessed. Cox regression analysis was used to determine the prognostic impact of NCCN-IPI scores and tumor necrosis status at CT. Results: There were no correlations between tumor necrosis status at CT and the NCCN-IPI factors categorized age (ρ = −0.042, P = 0.765), categorized lactate dehydrogenase (LDH) ratio (ρ = 0.201, P = 0.156), extranodal disease in major organs (φ = −0.245, P = 0.083), Ann Arbor stage III/IV disease (φ = −0.208, P = 0.141), and Eastern Cooperative Oncology Group (ECOG) performance status (φ = 0.015, P = 0.914). In the multivariate Cox proportional hazards model, only tumor necrosis status at CT was an independent predictive factor of progression-free survival (P = 0.003) and overall survival (P = 0.004). Conclusion: The findings of this study indicate the prognostic potential of tumor necrosis at CT in newly diagnosed DLBCL.

  3. Reduction of artefacts caused by hip implants in CT-based attenuation-corrected PET images using 2-D interpolation of a virtual sinogram on an irregular grid

    NARCIS (Netherlands)

    Abdoli, Mehrsima; de Jong, Johan R.; Pruim, Jan; Dierckx, Rudi A. J. O.; Zaidi, Habib

    2011-01-01

    Purpose Metallic prosthetic replacements, such as hip or knee implants, are known to cause strong streaking artefacts in CT images. These artefacts likely induce over-or underestimation of the activity concentration near the metallic implants when applying CT-based attenuation correction of positron

  4. CT value analysis and clinical significance before and after percutaneous lumbar discectomy

    Institute of Scientific and Technical Information of China (English)

    刘雷; 裴福兴; 宋跃明; 沈彬; 周宗科; 宋文锴; 张聪

    2002-01-01

    To provide theoretical basis for effect and mechanism of percutaneous lumbar discectomy in clinic. Methods: A total of 180 patients with lumbar intervertebral disc herniation were evaluated by CT on the fifth day before and after operation. Meanwhile, CT value was measured in the determined level and region. Results: After operation, CT value of the central and posterior determined point of herniated intervertebral disc was lower significantly than that before operation (P<0.01), but CT value of the anterior determined point was different insignificantly. The excellent and good results of the patients together were 83% postoperatively. Conclusions: The curative effect of percutaneous lumbar discectomy is achieved through reduction of lumbar intradiscal pressure.

  5. Q value of anelastic S-wave attenuation in Yunnan region

    Institute of Scientific and Technical Information of China (English)

    SU You-jin; LIU Jie; ZHENG Si-hua; LIU Li-fang; FU Hong; XU Yan

    2006-01-01

    @@ The study of seismic attenuation property is a major subject in seismology. Seismic waves recorded by seismic stations (seismographs) contain source effect, seismic wave propagation effect, site response of seismic stations and instrumental response. The path effect of seismic wave propagation, site response of seismic stations and instrumental response must be taken out in the study of source property with seismic data. The path effect of seismic wave propagation (seismic attenuation) involves an important influential factor, the anelastic attenuation of medium, which is measured with quality factor Q, apart from geometric attenuation with the distance. As a basic physical parameter of the Earth medium, Q value is essential for quantitative study of earthquakes and source property (e.g. determination of source parameters), which is widely used in earthquake source physics and engineering seismology.

  6. Recurrent pyogenic cholangitis: clinico-pathologic correlation of focal attenuation differences on multi-phasic spiral CT

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jun Yong; Han, Joon Koo; Kim, Tae Kyoung; Kim, Seog Joon; Kim, Hyun Bum; Choi, Byung Ihn [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2002-02-01

    To determine the clinical and the pathologic significance of the focal attenuation differences (FAD) and bile duct wall enhancement occurring in recurrent pyogenic cholangitis (RPC) and seen at multiphasic spiral CT. Among the multiphasic (non-contrast, arterial and portal or delayed phase) spiral CT findings of 60 consecutive patients, two types of FAD were noted during the non-contrast phase. These were Type A (iso) and Type B (low attenuation), and their distribution pattern (lobar versus patchy, multifocal) and the and the presence or absence of bile duct wall enhancement were recorded. The radiologic findings were correlated with the clinical and pathologic findings. Two types of FAD were noted in 40 of the 60 patients. Active in flammation was present in 19 of the 27 with Type-A and in ten of the 15 in whom the presence of RPC was pathologically proven. Ten of the 13 with Type-B FAD were in a subclinical state, and nine of the ten in whom RPC was pathologically proven had chronic inflammation. Among 20 patients who did not have FAD, RPC was subclinical in 18 and dormant in nine of the eleven in whom its presence was pathologically proven (p<0.001). Clinico-pathologic correlation with bile duct wall enhancement and the distribution pattern of FAD showed no statistical significance. The inflammatory activity of RPC can be predicted by analysis of the FAD seen at multiphasic spiral CT.

  7. One registration multi-atlas-based pseudo-CT generation for attenuation correction in PET/MRI

    Energy Technology Data Exchange (ETDEWEB)

    Arabi, Hossein [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva 4 (Switzerland); Zaidi, Habib [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva 4 (Switzerland); Geneva University, Geneva Neuroscience Center, Geneva (Switzerland); University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University of Southern Denmark, Department of Nuclear Medicine, Odense (Denmark)

    2016-10-15

    The outcome of a detailed assessment of various strategies for atlas-based whole-body bone segmentation from magnetic resonance imaging (MRI) was exploited to select the optimal parameters and setting, with the aim of proposing a novel one-registration multi-atlas (ORMA) pseudo-CT generation approach. The proposed approach consists of only one online registration between the target and reference images, regardless of the number of atlas images (N), while for the remaining atlas images, the pre-computed transformation matrices to the reference image are used to align them to the target image. The performance characteristics of the proposed method were evaluated and compared with conventional atlas-based attenuation map generation strategies (direct registration of the entire atlas images followed by voxel-wise weighting (VWW) and arithmetic averaging atlas fusion). To this end, four different positron emission tomography (PET) attenuation maps were generated via arithmetic averaging and VWW scheme using both direct registration and ORMA approaches as well as the 3-class attenuation map obtained from the Philips Ingenuity TF PET/MRI scanner commonly used in the clinical setting. The evaluation was performed based on the accuracy of extracted whole-body bones by the different attenuation maps and by quantitative analysis of resulting PET images compared to CT-based attenuation-corrected PET images serving as reference. The comparison of validation metrics regarding the accuracy of extracted bone using the different techniques demonstrated the superiority of the VWW atlas fusion algorithm achieving a Dice similarity measure of 0.82 ± 0.04 compared to arithmetic averaging atlas fusion (0.60 ± 0.02), which uses conventional direct registration. Application of the ORMA approach modestly compromised the accuracy, yielding a Dice similarity measure of 0.76 ± 0.05 for ORMA-VWW and 0.55 ± 0.03 for ORMA-averaging. The results of quantitative PET analysis followed the same

  8. Value of 3-D CT in classifying acetabular fractures during orthopedic residency training.

    Science.gov (United States)

    Garrett, Jeffrey; Halvorson, Jason; Carroll, Eben; Webb, Lawrence X

    2012-05-01

    The complex anatomy of the pelvis and acetabulum have historically made classification and interpretation of acetabular fractures difficult for orthopedic trainees. The addition of 3-dimensional (3-D) computed tomography (CT) scan has gained popularity in preoperative planning, identification, and education of acetabular fractures given their complexity. Therefore, the authors examined the value of 3-D CT compared with conventional radiography in classifying acetabular fractures at different levels of orthopedic training. Their hypothesis was that 3-D CT would improve correct identification of acetabular fractures compared with conventional radiography.The classic Letournel fracture pattern classification system was presented in quiz format to 57 orthopedic residents and 20 fellowship-trained orthopedic traumatologists. A case consisted of (1) plain radiographs and 2-dimensional axial CT scans or (2) 3-D CT scans. All levels of training showed significant improvement in classifying acetabular fractures with 3-D vs 2-D CT, with the greatest benefit from 3-D CT found in junior residents (postgraduate years 1-3).Three-dimensional CT scans can be an effective educational tool for understanding the complex spatial anatomy of the pelvis, learning acetabular fracture patterns, and correctly applying a widely accepted fracture classification system.

  9. Diagnostic value of PET/CT for the staging and restaging of pediatric tumors

    Energy Technology Data Exchange (ETDEWEB)

    Kleis, Margit [University of California (UCSF), Department of Radiology, San Francisco, CA (United States)]|[Technical University of Munich, Department of Radiology, Munich (Germany); Daldrup-Link, Heike; Lu, Ying; Schreck, Carole; Chu, Philip W.; Hawkins, Randall A.; Franc, Benjamin L. [University of California (UCSF), Department of Radiology, San Francisco, CA (United States); Matthay, Katherine [University of California, Department of Pediatrics, Division of Pediatric Hemato-Oncology, San Francisco, CA (United States); Goldsby, Robert [University of California, Department of Pediatric Oncology, San Francisco, CA (United States); Schuster, Tibor [Technical University of Munich, Department of Biostatistics and Epidemiology, Munich (Germany)

    2009-01-15

    The objective of this retrospective study was to compare the diagnostic value of 2-[{sup 18}F]fluoro-2-deoxy-d-glucose positron emission tomography ({sup 18}F-FDG PET)/CT versus {sup 18}F-FDG PET and CT alone for staging and restaging of pediatric solid tumors. Forty-three children and adolescents (19 females and 24 males; mean age, 15.2 years; age range, 6-20 years) with osteosarcoma (n = 1), squamous cell carcinoma (n = 1), synovial sarcoma (n = 2), germ cell tumor (n = 2), neuroblastoma (n = 2), desmoid tumor (n = 2), melanoma (n = 3), rhabdomyosarcoma (n = 5), Hodgkin's lymphoma (n = 7), non-Hodgkin-lymphoma (n = 9), and Ewing's sarcoma (n = 9) who had undergone {sup 18}F-FDG PET/CT imaging for primary staging or follow-up of metastases were included in this study. The presence, location, and size of primary tumors was determined separately for PET/CT, PET, and CT by two experienced reviewers. The diagnosis of the primary tumor was confirmed by histopathology. The presence or absence of metastases was confirmed by histopathology (n = 62) or clinical and imaging follow-up (n = 238). The sensitivities for the detection of solid primary tumors using integrated {sup 18}F-FDG PET/CT (95%), {sup 18}F-FDG PET alone (73%), and CT alone (93%) were not significantly different (p > 0.05). Seventeen patients showed a total of 153 distant metastases. Integrated PET/CT had a significantly higher sensitivity for the detection of these metastases (91%) than PET alone (37%; p < 0.05), but not CT alone (83%; p > 0.05). When lesions with a diameter of less than 0.5 cm were excluded, PET/CT (89%) showed a significantly higher specificity compared to PET (45%; p < 0.05) and CT (55%; p < 0.05). In a sub-analysis of pulmonary metastases, the values for sensitivity and specificity were 90%, 14%, 82% and 63%, 78%, 65%, respectively, for integrated PET/CT, stand-alone PET, and stand-alone CT. For the detection of regional lymph node metastases, {sup 18}F-FDG PET/CT, {sup 18}F

  10. Technological value of SPECT/CT fusion imaging for the diagnosis of lower gastrointestinal bleeding.

    Science.gov (United States)

    Wang, Z G; Zhang, G X; Hao, S H; Zhang, W W; Zhang, T; Zhang, Z P; Wu, R X

    2015-11-24

    The aim of this study was to assess the clinical value of diagnosing and locating lower gastrointestinal (GI) bleeding using single photon emission computed tomography (SPECT)/computed tomography (CT) fusion imaging with 99mTc labeled red blood cells ((99m)Tc-RBC). Fifty-six patients with suspected lower GI bleeding received a preoperative intravenous injection of (99m)Tc-RBC and each underwent planar, SPECT/CT imaging of the lower abdominal region. The location and path of lower GI bleeding were diagnosed by contrastive analysis of planar and SPECT/CT fusion imaging. Among the 56 patients selected, there were abnormalities in concentrated radionuclide activity with planar imaging in 50 patients and in SPECT/CT fusion imaging in 52 patients. Moreover, bleeding points that were coincident with the surgical results were evident with planar imaging in 31 patients and with SPECT/CT fusion imaging in 48 patients. The diagnostic sensitivity of planar imaging and SPECT/CT fusion imaging were 89.3% (50/56) and 92.9% (52/56), respectively, and the difference was not statistically significant (χ(2) = 0.11, P > 0.05). The corresponding positional accuracy values were 73.8% (31/42) and 92.3% (48/52), and the difference was statistically significant (χ(2) = 4.63, P CT fusion imaging is an effective, simple, and accurate method that can be used for diagnosing and locating lower GI bleeding.

  11. Clinical value of a combined multi-phase contrast enhanced DOPA-PET/CT in neuroendocrine tumours with emphasis on the diagnostic CT component

    Energy Technology Data Exchange (ETDEWEB)

    Veit-Haibach, Patrick [University Hospital Zurich, Department of Medical Radiology, Division of Nuclear Medicine, Zuerich (Switzerland); Lucerne Cantonal Hospital, Department of Radiology and Nuclear Medicine, Lucerne (Switzerland); Schiesser, Marc; Clavien, P.A. [University Hospital Zurich, Department of Surgery, Zurich (Switzerland); Soyka, Jan; Strobel, Klaus; Hesselmann, Rolf; Hany, Thomas F. [University Hospital Zurich, Department of Medical Radiology, Division of Nuclear Medicine, Zuerich (Switzerland); Schaefer, Niklaus G. [University Hospital Zurich, Department of Medical Radiology, Division of Nuclear Medicine, Zuerich (Switzerland); University Hospital Zurich, Department of Oncology, Zurich (Switzerland)

    2011-02-15

    To assess the clinical value of multi-phase, contrast-enhanced DOPA-PET/CT with emphasis on the diagnostic CT component in patients with neuroendocrine tumours (NET). Sixty-five patients with NET underwent DOPA-cePET/CT. The DOPA-PET, multi-phase CT and combined DOPA cePET/CT data were evaluated and diagnostic accuracies compared. The value of ceCT in DOPA cePET/CT concerning lesion detection and therapeutic impact was evaluated. Sensitivities, specificities and accuracies were calculated. Histopathology and clinical follow-up served as the standard of reference. Differences were tested for statistical significance by McNemar's test. In 40 patients metastatic and/or primary tumour lesions were detected. Lesion-based analysis for the DOPA-PET showed sensitivity, specificity and accuracy of 66%, 100% and 67%, for the ceCT data 85%, 71% and 85%, and for the combined DOPA cePET/CT data 97%, 71% and 96%. DOPA cePET/CT was significantly more accurate compared with dual-phase CT (p < 0.05) and PET alone (p < 0.05). Additional lesion detection was based on ceCT in 12 patients; three patients underwent significant therapeutic changes based on the ceCT findings. DOPA cePET/CT was significantly more accurate than DOPA-PET alone and ceCT alone. The CT component itself had a diagnostic impact in a small percentage but contributed to the therapeutic strategies in selected patients. (orig.)

  12. The value of baseline CT head scans in the assessment of shunt complications in hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, P. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Fraser, F. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Pilling, D. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Carty, H. (Alder Hey Children' s Hospital, Liverpool (United Kingdom))

    1993-10-01

    The purpose of this study was to determine the value of a baseline CT head scan in the assessment of patients who subsequently presented with symptoms which may have been due to shunt complications (such as blockage or infection). In all these patients the shunt had been inserted in the treatment of hydrocephalus. We conclude that the presence of a baseline scan does not add to the interpretation of CT scans done when the patient presents with symptoms of possible shunt malfunction. (orig.)

  13. Diagnostic value of dual-source CT in Kawasaki disease

    Institute of Scientific and Technical Information of China (English)

    CHAO Bao-ting; WANG Xi-ming; WU Le-bin; CHEN Jie; CHENG Zhao-ping; WU Da-wei; DUAN Yan-hua

    2010-01-01

    Background Doppler color echocardiography is a common method for detecting coronary artery lesions in patients with Kawasaki disease(KD).However,the diagnostic accuracy for the whole coronary artery lesions is limited.The purpose of this study was to compare the diagnostic value of dual-source computed tomography (DSCT) and Doppler color echocardiography for the assessment of coronary artery lesions caused by KD.Methods Sixteen patients,12 with typical KD and 4 with atypical KD,underwent DSCT and Doppler color echocardiography.The position and internal diameter of each coronary artery lesion was measured.Correlation analysis was used to compare the diagnostic value of the two imaging modalities.Results ln the typical KD group, seven patients did not have any coronary artery Iesion as confirmed by both DSCT scans and Doppler color echocardiography;in four patients proximal coronary artery injuries were identified by both modalities;in one patient an aneurysm in the middle and distal segments of the coronary artery was detected by DSCT but was negative in Doppler color echocardiography.In the atypical KD group,three cases showed the same results with both modalities,while one case with coronary artery stenosis in the middle segment was identified by DSCT but not detected by Doppler color echocardiography.There was a good correlation between the two imaging modalities(Kappa value,0.768(≥0.75)).Conclusion DSCT coronary artery angiography is an accurate,non-invasive,and valuable technique for detecting and following up coronary artery lesions in patients with KD.

  14. Aneurysms complicating inflammatory diseases in immunocompromised hosts: value of contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Heussel, C.P. [Dept. of Radiology, Univ. of Mainz (Germany); Kauczor, H.U. [Dept. of Radiology, Univ. of Mainz (Germany); Heussel, G. [Dept. of Hematology, Univ. of Mainz (Germany); Mildenberger, P. [Dept. of Radiology, Univ. of Mainz (Germany); Dueber, C. [Dept. of Radiology, Univ. of Mainz (Germany)

    1997-04-01

    We studied the value of contrast-enhanced CT in the detection of aneurysms in immunocompromised patients suffering from inflammatory diseases eventually complicated by hemorrhage. Contrast-enhanced spiral CT was applied in three patients with immunocompromise due to chemotherapy, alcohol abuse or HIV. They suffered from invasive aspergillosis, chronic pancreatitis with pseudocyst formation, and acute pancreatitis together with HIV-associated lymphadenopathy. Complicating hemorrhage was present in two cases. Contrast-enhanced CT showed aneurysms complicating the underlying inflammatory disease in all three cases. The feeding vessels were identified and the patients with signs of bleeding were subsequently referred for angiography and embolization. Contrast-enhanced spiral CT is suited to detect aneurysms in immunocompromised patients suffering from inflammatory disease. It is recommended in these patients prior to angiography and intervention. (orig.). With 3 figs.

  15. Value of PET/CT in the approach to head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Curioni, Otavio Alberto; Amar, Ali; Viana, Debora [Hospital Heliopolis, Sao Paulo, SP (Brazil). Service of Head and Neck Surgery and Otorhynolaryngology; Souza, Ricardo Pires de [Hospital Heliopolis, Sao Paulo, SP (Brazil). Service of Radiology; Rapoport, Abrao [Hospital Heliopolis, Sao Paulo, SP (Brazil); Dedivitis, Rogerio Aparecido [Universidade de Sao Paulo (HC-FMUSP), SP (Brazil). Hospital das Clinicas. Group of Larynx and Hypopharynx; Cernea, Claudio Roberto; Brandao, Lenine Garcia [Universidade de Sao Paulo (FMUSP), SP (Brazil). Fac. de Medicina. Dept. of Head and Neck Surgery

    2012-11-15

    Objective: To evaluate the role of PET/CT in the approach to patients with head and neck cancer. Materials and Methods: Retrospective study of medical records and PET/CT images of 63 patients with head and neck cancer. Results: Alterations were observed in 76% of the cases. Out of these cases, 7 (11%) were considered as false-positive, with SUV < 5.0. PET/CT demonstrated negative results in 15 cases (24%). Among the 14 cases where the method was utilized for staging, 3 (22%) had their stages changed. Conclusion: PET/CT has shown to be of potential value in the routine evaluation of patients with head and neck cancer, but further studies of a higher number of cases are required to define a protocol for utilization of the method. (author)

  16. Diagnostic Value of 16 Slices Spiral-CT for Portal Vein Disorders

    Institute of Scientific and Technical Information of China (English)

    李震; 胡道予; 肖明

    2004-01-01

    Summary: The diagnostic value of 16-slices spiral computed tomography (CT) for portal vein disorders was evaluated. Forty-one patients were scanned by the 16-slices spiral-CT. The celiac trunk,portal vein and their branches were reconstructed by volume rendering (VR), multiplanar volume reconstruction (MPVR) and maximum intensity projection (MIP) technique, and the results were compared with digital subtraction angiography (DSA). VR, MPVR and MIP could display celiac trunk, portal vein, inferior vena cava and their branches and extent of portal vein-vena cava shunt,portal vein emboli and the fistula of hepatic artery-portal vein. The results from 16-slices CT were better than DSA and identical with pathologic ones. The vessel three-dimension reconstruction technique of 16-slices spiral CT is valuable for evaluating the portal systemic disorders.

  17. Additional value of hybrid SPECT/CT systems in neuroendocrine tumors, adrenal tumors, pheochromocytomas and paragangliomas.

    Science.gov (United States)

    Wong, K K; Chondrogiannis, S; Fuster, D; Ruiz, C; Marzola, M C; Giammarile, F; Colletti, P M; Rubello, D

    The aim of this review was to evaluate the potential advantages of SPECT/CT hybrid imaging in the management of neuroendocrine tumors, adrenal tumors, pheochromocytomas and paragangliomas. From the collected data, the superiority of fused images was observed as providing both functional/molecular and morphological imaging compared to planar imaging. This provided an improvement in diagnostic imaging, with significant advantages as regards: (1) precise locating of the lesions; (2) an improvement in characterization of the findings, resulting higher specificity, improved sensitivity, and overall greater accuracy, (3) additional anatomical information derived from the CT component; (4) CT-based attenuation correction and potential for volumetric dosimetry calculations, and (5) improvement on the impact on patient management (e.g. in better defining treatment plans, in shortening surgical operating times). It can be concluded that SPECT/CT hybrid imaging provides the nuclear medicine physician with a powerful imaging modality in comparison to planar imaging, providing essential information about the location of lesions, and high quality homogeneous images. Copyright © 2016 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  18. Early interim FDG PET/CT prediction of treatment response and prognosis in pediatric Hodgkin disease - added value of low-dose CT

    Energy Technology Data Exchange (ETDEWEB)

    Ilivitzki, Anat [Rambam Health Care Campus, Department of Diagnostic Imaging, Haifa (Israel); Rambam Health Care Campus, Department of Pediatric Radiology, Haifa (Israel); Radan, Lea; Israel, Ora [Rambam Health Care Campus, Department of Nuclear Medicine, Haifa (Israel); Ben-Arush, Miriam; Ben-Barak, Ayelet [Rambam Health Care Campus, Department of Pediatric Oncology, Haifa (Israel)

    2013-01-15

    Interim 18F-FDG PET helps predict outcome and tailor treatment in adults with Hodgkin disease (HD). The purpose of this study was to assess predictive values of interim 18F-FDG PET/CT in children with HD and to define the potential added value to interim PET of low-dose CT. Children were prospectively enrolled August 2002-April 2007. PET/low-dose CT was performed at staging, after 2 cycles, at the end of treatment and during follow-up (mean 45 months). Treatment was unchanged regardless of interim results. PET and low-dose CT were read independently. Of 34 enrolled children (ages 3-17 years), 27 achieved complete response, 4 had progressive disease and 3 had relapse. Interim PET alone had positive and negative predictive values of 67% and 89%, respectively. Interim low-dose CT alone had positive and negative predictive values of 35% and 100%, respectively. Interim PET/CT had positive and negative predictive values of 75% and 96%, respectively. Early interim PET/CT was a good predictor of outcome. Integrated PET and low-dose CT improved the predictive value in children with HD. (orig.)

  19. Diagnosis of nutcracker syndrome of the left renal vein. Value of the corticomedullary phase of helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Igari, Hidenori [Yokohama Comprehensive Care Continuum (Japan)

    2001-05-01

    The clinical significance of the corticomedullary phase of helical CT in the diagnosis of nutcracker syndrome of the left renal vein (LRV) was evaluated. A total of 38 patients with hematuria of unknown origin (12 men and 26 women, mean age 24 years [range: 18-32 years]) were examined by helical CT of the kidneys, retrograde left renal venography, and measurement of renocaval pressure gradients. The sensitivity and specificity of the corticomedullary and nephrographic phases of helical CT for detecting the nutcracker syndrome were determined. The nutcracker syndrome was diagnosed on the basis of the renography findings combined with pressure measurements in 19 patients: 12 with LRV hypertension and collateral veins, 1 with hypertension and no collateral veins, and 6 with collateral veins and normal pressure gradients or borderline hypertension. Both the corticomedullary- and nephrographic-phase images revealed distended LRVs in 26 (68%) of the 38 patients. The LRV mean attenuation values in the corticomedullary phase (164{+-}22 Hounsfield units [H], range: 138-209 H) was significantly greater (p<0.001) than in the nephrographic phase (80{+-}14 H, range: 62-100 H). During the corticomedullary phase, opacified blood from the renal vein was mixed with unopacified blood in the IVC. In the nephrographic phase, however, the IVC was enhanced homogeneously, but only slightly. Corticomedullary-phase imaging detected collateral veins that exhibited early enhancement, indicating retrograde flow from the LRVs in 15 out of 18 patients (83% of those with collateral veins), while the nephrographic-phase imaging revealed collateral veins in 8 patients (44% of those with collateral veins). The sensitivity and specificity of the corticomedullary-phase scan for detecting the nutcracker syndrome were 79% and 100%, respectively, as opposed to 42% and 100%, respectively, for the nephrographic phase. Retrograde flow from the LRV into the collateral veins in the corticomedullary phase is

  20. Reliability of attenuation measurements in CT of the lumbar spine: evaluation with an anthropomorphic phantom.

    Science.gov (United States)

    Moström, U; Ytterbergh, C

    1988-01-01

    A phantom was constructed with the intention of simulating the clinical situation at examination of the spine. Artifacts from bony vertebral structures were analyzed and the uniformity in a body-shaped object was studied. Tests were carried out on eight CT scanners. A considerable variation in uniformity was found between the tested scanner models. The CT numbers within the spinal canal and in a region anterior to the spine were elevated for most of the scanners. The deviation varied considerably, however, between models.

  1. Value of monoenergetic dual-energy CT (DECT) for artefact reduction from metallic orthopedic implants in post-mortem studies

    Energy Technology Data Exchange (ETDEWEB)

    Filograna, Laura [University of Zurich, Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, Zurich (Switzerland); Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Department of Radiological Sciences, Rome (Italy); Magarelli, Nicola; Leone, Antonio; Bonomo, Lorenzo [Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Department of Radiological Sciences, Rome (Italy); Guggenberger, Roman; Winklhofer, Sebastian [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Thali, Michael John [University of Zurich, Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, Zurich (Switzerland)

    2015-09-15

    The aim of this ex vivo study was to assess the performance of monoenergetic dual-energy CT (DECT) reconstructions to reduce metal artefacts in bodies with orthopedic devices in comparison with standard single-energy CT (SECT) examinations in forensic imaging. Forensic and clinical impacts of this study are also discussed. Thirty metallic implants in 20 consecutive cadavers with metallic implants underwent both SECT and DECT with a clinically suitable scanning protocol. Extrapolated monoenergetic DECT images at 64, 69, 88, 105, 120, and 130 keV and individually adjusted monoenergy for optimized image quality (OPTkeV) were generated. Image quality of the seven monoenergetic images and of the corresponding SECT image was assessed qualitatively and quantitatively by visual rating and measurements of attenuation changes induced by streak artefact. Qualitative and quantitative analyses showed statistically significant differences between monoenergetic DECT extrapolated images and SECT, with improvements in diagnostic assessment in monoenergetic DECT at higher monoenergies. The mean value of OPTkeV was 137.6 ± 4.9 with a range of 130 to 148 keV. This study demonstrates that monoenergetic DECT images extrapolated at high energy levels significantly reduce metallic artefacts from orthopedic implants and improve image quality compared to SECT examination in forensic imaging. (orig.)

  2. Recurrent renal cell carcinoma: clinical and prognostic value of FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Alongi, Pierpaolo; Picchio, Maria; Gianolli, Luigi [IRCCS San Raffaele Scientific Institute, Nuclear Medicine Department, Milan (Italy); Zattoni, Fabio [University of Padua, Department of Oncological and Surgical Sciences, Urology Clinic, Padua (Italy); Spallino, Marianna [University of Milano-Bicocca, Milan (Italy); Saladini, Giorgio; Evangelista, Laura [Veneto Institute of Oncology IOV - IRCCS, Padua, Italy, Radiotherapy and Nuclear Medicine Unit, Padua (Italy)

    2016-03-15

    The purpose of our study was 1) to evaluate the diagnostic performance of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT), 2) to assess the impact of FDG PET/CT on treatment decision-making, and 3) to estimate the prognostic value of FDG PET/CT in the restaging process among patients with renal cell carcinoma (RCC). From the FDG PET/CT databases of San Raffaele Hospital in Milan, Italy, and the Veneto Institute of Oncology in Padua, Italy, we selected 104 patients with a certain diagnosis of RCC after surgery, and for whom at least 24 months of post-surgical FDG PET/CT, clinical, and instrumental follow-up data was available. The sensitivity and specificity of FDG PET/CT were assessed by histology and/or other imaging as standard of reference. Progression-free survival (PFS) and overall survival (OS) were computed using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards models were used to identify predictors of outcome. FDG PET/CT resulted in a positive diagnosis in 58 patients and a negative diagnosis in 46 patients. Sensitivity and specificity were 74 % and 80 %, respectively. FDG PET/CT findings influenced therapeutic management in 45/104 cases (43 %). After a median follow-up period of 37 months (± standard deviation 12.9), 51 (49 %) patients had recurrence of disease, and 26 (25 %) had died. In analysis of OS, positive versus negative FDG PET/CT was associated with worse cumulative survival rates over a 5-year period (19 % vs. 69 %, respectively; p <0.05). Similarly, a positive FDG PET/CT correlated with a lower 3-year PFS rate. In addition, univariate and multivariate analysis revealed that a positive scan, alone or in combination with disease stage III-IV or nuclear grading 3-4, was associated with high risk of progression (multivariate analysis = hazard ratios [HRs] of 4.01, 3.7, and 2.8, respectively; all p < 0.05). FDG PET/CT is a valuable tool both in treatment decision-making and for

  3. A Systematic Review of the Diagnostic Value of CT Imaging in Diagnosing Otosclerosis

    NARCIS (Netherlands)

    Wegner, Inge; van Waes, Anne M A; Bittermann, Arnold J; Buitinck, Sophie H; Dekker, Caroline F; Kurk, Sophie A; Rados, Matea; Grolman, Wilko

    OBJECTIVE: To evaluate the diagnostic value of computed tomography (CT) in detecting otosclerosis in patients with conductive hearing loss and a clinical suspicion of otosclerosis. DATA SOURCES: PubMed, Embase, and the Cochrane Library. STUDY SELECTION: A systematic search was conducted. Studies

  4. Influence of cone beam CT scanning parameters on grey value measurements at an implant site

    NARCIS (Netherlands)

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

    2013-01-01

    Objectives: The aim of this study was to determine the grey value variation at the implant site with different scan settings, including field of view (FOV), spatial resolution, number of projections, exposure time and dose selections in two cone beam CT (CBCT) systems and to compare the results with

  5. Comparison of Haller index values calculated with chest radiographs versus CT for pectus excavatum evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Khanna, Geetika; Jaju, Alok; Don, Steven; Hildebolt, Charles F. [Washington University School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Keys, Tim [Medical Physics Services Ltd., St Louis, MO (United States)

    2010-11-15

    Pectus excavatum is a common chest wall anomaly in children. Pre-operative imaging for pectus excavatum is performed with CT, which is used to calculate the Haller index to determine the severity of pectus excavatum. To determine the correlation between Haller index values calculated with two-view chest radiographs and those calculated with CT and to determine, with CT as the reference standard, the diagnostic performance of radiographic Haller index for identifying cases that meet imaging criteria for surgical correction of pectus excavatum. For the period 2001-2009, our radiology information system was searched to identify all children who had undergone CT for Haller index calculation. Children who had also undergone two-view chest radiography (CXR) within 6 months of the CT were included in this retrospective study. Two radiologists independently calculated CT Haller index and radiographic Haller index. Data distributions were tested for normality with the Shapiro-Wilk W test. The associations between CT Haller index and radiographic Haller index were determined with the Spearman coefficient of rank correlation. Differences between CT Haller index and radiographic Haller index were tested with the Wilcoxon signed rank test. Haller index values were dichotomized into positive (>3.2) and negative ({<=}3.2) cases. Using CT as the reference standard, the sensitivity, specificity, and accuracy of radiographic Haller index in identifying children who meet imaging criteria for surgery were calculated. CT and CXR for evaluation of pectus excavatum were available for 32 children (25 male; median age 14.5 years). With CT, the median Haller indices for observers 1 and 2 were 3.4 and 3.5 and with CXR 3.5 and 3.5. There were statistically significant correlations between the radiographic Haller index and CT Haller index estimated by the two observers [Spearman correlation coefficient (95% confidence interval) for observer 1 = 0.71 (0.48-0.85, P < 0.01) and for observer 2 = 0

  6. Cardiac fusion and complex congenital cardiac defects in thoracopagus twins: diagnostic value of cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Park, Jeong-Jun [University of Ulsan College of Medicine, Asan Medical Center, Department of Pediatric Cardiac Surgery, Seoul (Korea, Republic of); Kim, Ellen Ai-Rhan [University of Ulsan College of Medicine, Asan Medical Center, Division of Neonatology, Department of Pediatrics, Seoul (Korea, Republic of); Won, Hye-Sung [University of Ulsan College of Medicine, Asan Medical Center, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of)

    2014-09-15

    Most thoracopagus twins present with cardiac fusion and associated congenital cardiac defects, and assessment of this anatomy is of critical importance in determining patient care and outcome. Cardiac CT with electrocardiographic triggering provides an accurate and quick morphological assessment of both intracardiac and extracardiac structures in newborns, making it the best imaging modality to assess thoracopagus twins during the neonatal period. In this case report, we highlight the diagnostic value of cardiac CT in thoracopagus twins with an interatrial channel and complex congenital cardiac defects. (orig.)

  7. Interleaving cerebral CT perfusion with neck CT angiography. Pt. I. Proof of concept and accuracy of cerebral perfusion values

    Energy Technology Data Exchange (ETDEWEB)

    Oei, Marcel T.H.; Meijer, Frederick J.A.; Woude, Willem-Jan van der; Smit, Ewoud J.; Ginneken, Bram van; Prokop, Mathias; Manniesing, Rashindra [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, P.O. Box 9101, Nijmegen (Netherlands)

    2017-06-15

    We present a novel One-Step-Stroke protocol for wide-detector CT scanners that interleaves cerebral CTP with volumetric neck CTA (vCTA). We evaluate whether the resulting time gap in CTP affects the accuracy of CTP values. Cerebral CTP maps were retrospectively obtained from 20 patients with suspicion of acute ischemic stroke and served as the reference standard. To simulate a 4 s gap for interleaving CTP with vCTA, we eliminated one acquisition at various time points of CTP starting from the bolus-arrival-time(BAT). Optimal timing of the vCTA was evaluated. At the time point with least errors, we evaluated elimination of a second time point (6 s gap). Mean absolute percentage errors of all perfusion values remained below 10 % in all patients when eliminating any one time point in the CTP sequence starting from the BAT. Acquiring the vCTA 2 s after reaching a threshold of 70HU resulted in the lowest errors (mean <3.0 %). Eliminating a second time point still resulted in mean errors <3.5 %. CBF/CBV showed no significant differences in perfusion values except MTT. However, the percentage errors were always below 10 % compared to the original protocol. Interleaving cerebral CTP with neck CTA is feasible with minor effects on the perfusion values. (orig.)

  8. Assessment value of quantitative indexes of pancreatic CT perfusion scanning for malignant degree of pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Jiang-Xia Lei

    2016-01-01

    Objective:To analyze the assessment value of the quantitative indexes of pancreatic CT perfusion scanning for malignant degree of pancreatic cancer.Methods:A total of 58 patients with space-occupying pancreatic lesions were divided into 20 patients with pancreatic cancer and 38 patients with benign pancreatic lesions after pancreatic CT perfusion. Patients with pancreatic cancer received palliative surgery, and the cancer tissue and para-carcinoma tissue specimens were collected during operation. The differences in pancreatic CT perfusion scanning parameter values and serum tumor marker levels were compared between patients with pancreatic cancer and patients with benign pancreatic lesions, mRNA expression levels of malignant molecules in pancreatic cancer tissue and para-carcinoma tissue were further determined, and the correlation between pancreatic CT perfusion scanning parameter values and malignant degree of pancreatic cancer was analyzed.Results:CT perfusion scanning BF, BV and Per values of patients with pancreatic cancer were lower than those of patients with benign pancreatic lesions; serum CA19-9, CEA, CA125 and CA242 levels were higher than those of patients with benign pancreatic lesions (P<0.05); mRNA expression levels of Bcl-2, Bcl-xL andsurvivin in pancreatic cancer tissue samples were higher than those in para-carcinoma tissue samples, and mRNA expression levels ofP53 andBax were lower than those in para-carcinoma tissue samples (P<0.05); CT perfusion scanning parameters BF, BV and Per values of patients with pancreatic cancer were negatively correlated with CA19-9, CEA, CA125 and CA242 levels in serum as well as mRNA expression levels ofBcl-2, Bcl-xL and survivinin pancreatic cancer tissue, and positively correlated with mRNA expression levels ofP53andBaxin pancreatic cancer tissue (P<0.05).Conclusions:Pancreatic CT perfusion scanning is a reliable way to judge the malignant degree of pancreatic cancer and plays a positive role in guiding clinical

  9. Diagnostic value of 3 D CT surface reconstruction in spinal fractures

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, S. [Department of Radiology, Univ. of Leipzig (Germany); Dietrich, K. [Department of Radiology, Univ. of Leipzig (Germany); Steinecke, R. [Department of Radiology, Univ. of Leipzig (Germany); Kloeppel, R. [Department of Radiology, Univ. of Leipzig (Germany); Schulz, H.G. [Department of Radiology, Univ. of Leipzig (Germany)

    1997-02-01

    Our purpose was to evaluate the diagnostic value of three-dimensional (3 D) CT surface reconstruction in spinal fractures in comparison with axial and reformatted images. A total of 50 patients with different CT-proven spinal fractures were analysed retrospectively. Based on axial scans and reformatted images, the spinal fractures were classified according to several classifications as Magerl for the thoraco-lumbar and lower cervical spine by one radiologist. Another radiologist performed 3 D CT surface reconstructions with the aim of characterizing the different types of spinal fractures. A third radiologist classified the 3 D CT surface reconstruction according to the Magerl classification. The results of the blinded reading process were compared. It was checked to see in which type and subgroup 3 D surface reconstructions were helpful. Readers one and two obtained the same results in the classification. The 3 D surface reconstruction did not yield any additional diagnostic information concerning type A and B injuries. Indeed, the full extent of the fracture could be easier recognized with axial and reformatted images in all cases. In 10 cases of C injuries, the dislocation of parts of vertebrae could be better recognized with the help of 3 D reconstructions. A 3 D CT surface reconstruction is only useful in rotational and shear vertebral injuries (Magerl type C injury). (orig.). With 4 figs., 1 tab.

  10. Value of CT in the Discrimination of Fatal from Non-Fatal Stercoral Colitis

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Cheng Hsien; Huang, Chen Chin; Wang, Li Jen; Wong, Yon Cheng; Wang, Chao Jan; Lo, Wang Chak; Lin, Being Chuan; Wan, Yung Liang; Haueh, Chuen [Chang Gung Memorial Hospital, Chang Gung University, Taoyuan (China)

    2012-06-15

    Clinical presentation and physical signs may be unreliable in the diagnosis of stercoral colitis (SC). This study evaluates the value of computed tomography (CT) in distinguishing fatal from non-fatal SC. Ten patients diagnosed as SC were obtained from inter-specialist conferences. Additional 13 patients with suspected SC were identified via the Radiology Information System (RIS). These patients were divided into two groups; fatal and non-fatal SCs. Their CT images are reviewed by two board-certified radiologists blinded to the clinical data and radiographic reports. SC occurred in older patients and displayed no gender predisposition. There was significant correlation between fatal SC and CT findings of dense mucosa (p 0.017), perfusion defects (p = 0.026), ascites (p = 0.023), or abnormal gas (p = 0.033). The sensitivity, specificity, and accuracy of dense mucosa were 71%, 86%, and 81%, respectively. These figures were 75%, 79%, and 77% for perfusion defects; 75%, 80%, and 78% for ascites; and 50%, 93%, and 78% for abnormal gas, respectively. Each CT sign of mucosal sloughing and pericolonic abscess displayed high specificity of 100% and 93% for diagnosing fatal SC, respectively. However, this did not reach statistical significance in diagnosing fatal SC. CT appears to be valuable in discriminating fatal from non-fatal SC.

  11. Value of three-dimensional reconstructions in pancreatic carcinoma using multidetector CT: Initial results

    Institute of Scientific and Technical Information of China (English)

    Miriam Klauβ; Max Sch(o)binger; Ivo Wolf; Jens Werner; Hans-Peter Meinzer; Hans-Ulrich Kauczor; Lars Grenacher

    2009-01-01

    AIM: To evaluate the use of three-dimensional imaging of pancreatic carcinoma using multidetector computed tomography (CT) in a prospective study. METHODS: Ten patients with suspected pancreatic tumors were examined prospectively using multidetector CT (Somatom Sensation 16, Siemens, Erlangen, Germany). The images were evaluated for the presence of a pancreatic carcinoma and invasion of the peripancreatic vessels and surrounding organs. Using the isotropic CT data sets, a three-dimensional image was created with automatic vascular analysis and semiautomatic segmentation of the organs and pancreatic tumor by a radiologist. The CT examinations and the three-dimensional images were presented to the surgeon directly before and during the patient's operation using the Medical Imaging Interaction Toolkit-based software "ReLiver". Immediately after surgery, the value of the two images was judged by the surgeon. The operation and the histological results served as the gold standard. RESULTS: Nine patients had a pancreatic carcinoma (all pT3), and one patient had a serous cystadenoma. One tumor infiltrated the superior mesenteric vein. The infiltration was correctly evaluated. All carcinomas were resectable. In comparison to the CT image with axial and coronal reconstructions, the three-dimensional image was judged by the surgeons as better for operation planning and consistently described as useful. CONCLUSION: A 3D-image of the pancreas represents an invaluable aid to the surgeon. However, the 3D-software must be further developed in order to be integrated into daily clinical routine.

  12. Clinical value of FDG-PET/CT in suspected paraneoplastic syndromes

    DEFF Research Database (Denmark)

    Kristensen, Stine Bjørn; Hess, Søren; Petersen, Henrik

    2015-01-01

    PURPOSE: Paraneoplastic syndromes (PNS) are relatively infrequent manifestations appearing before or after a cancer declares itself. Autoimmune mechanisms may be involved, but their cause and pathogenesis are often unknown. Due to disparity of symptoms, PNS remain a major diagnostic challenge. We...... examined the value of FDG-PET/CT for ruling in or out malignancy in a heterogeneous group of patients with suspected PNS. METHODS: We retrospectively extracted data from all patients referred 2009-2013 with suspected PNS. Data included age, sex, follow-up period, scan report, further diagnostic procedures...... true positives, 22 false positives, 103 true negatives, and three false negatives. Corresponding diagnostic values were: sensitivity 75 %, specificity 82 %, accuracy 82 %, and positive and negative predictive values of 29 % and 97 %, respectively. CONCLUSION: FDG-PET/CT has in patients with suspected...

  13. Use of time attenuation curves to determine steady-state characteristics before C-arm CT measurement of cerebral blood volume

    Energy Technology Data Exchange (ETDEWEB)

    Caroff, Jildaz; Jittapiromsak, Pakrit; Benachour, Nidhal; Mihalea, Cristian; Rouchaud, Aymeric; Neki, Hiroaki; Ikka, Leon; Moret, Jacques; Spelle, Laurent [Beaujon Medical Center, NEURI - Interventional Neuroradiology, Paris Diderot University, Clichy (France); Ruijters, Daniel [Philips Healthcare, Interventional X-Ray Innovation, Best (Netherlands)

    2014-03-15

    Cerebral blood volume (CBV) measurement by flat panel detector CT (FPCT) in the angiography suite seems to be a promising tool for patient management during endovascular therapies. A steady state of contrast agent distribution is mandatory during acquisition for accurate FPCT CBV assessment. To the best of our knowledge, this was the first time that steady-state parameters were studied in clinical practice. Before the CBV study, test injections were performed and analyzed to determine a customized acquisition delay from injection for each patient. Injection protocol consisted in the administration of 72 mL of contrast agent material at the injection rate of 4.0 mL/s followed by a saline flush bolus at the same injection rate. Peripheral or central venous accesses were used depending on their availability. Twenty-four patients were treated for different types of neurovascular diseases. Maximal attenuation, steady-state length, and steady-state delay from injection were derived from the test injections' time attenuation curves. With a 15 % threshold from maximum attenuation values, average steady-state duration was less than 10 s. Maximum average steady-state duration with minimal delay variation was obtained with central injection protocols. With clinically acceptable contrast agent volumes, steady state is a brief condition; thus, fast rotation speed acquisitions are needed. The use of central injections decreases the variability of steady-state's delay from injection. Further studies are needed to optimize and standardize injection protocols to allow a larger diffusion of the FPCT CBV measurement during endovascular treatments. (orig.)

  14. Reduction of artefacts caused by hip implants in CT-based attenuation-corrected PET images using 2-D interpolation of a virtual sinogram on an irregular grid

    Energy Technology Data Exchange (ETDEWEB)

    Abdoli, Mehrsima; Jong, Johan R. de; Pruim, Jan; Dierckx, Rudi A.J.O. [University of Groningen, Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen (Netherlands); Zaidi, Habib [University of Groningen, Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen (Netherlands); Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva (Switzerland); Geneva University, Geneva Neuroscience Center, Geneva (Switzerland)

    2011-12-15

    Metallic prosthetic replacements, such as hip or knee implants, are known to cause strong streaking artefacts in CT images. These artefacts likely induce over- or underestimation of the activity concentration near the metallic implants when applying CT-based attenuation correction of positron emission tomography (PET) images. Since this degrades the diagnostic quality of the images, metal artefact reduction (MAR) prior to attenuation correction is required. The proposed MAR method, referred to as virtual sinogram-based technique, replaces the projection bins of the sinogram that are influenced by metallic implants by a 2-D Clough-Tocher cubic interpolation scheme performed in an irregular grid, called Delaunay triangulated grid. To assess the performance of the proposed method, a physical phantom and 30 clinical PET/CT studies including hip prostheses were used. The results were compared to the method implemented on the Siemens Biograph mCT PET/CT scanner. Both phantom and clinical studies revealed that the proposed method performs equally well as the Siemens MAR method in the regions corresponding to bright streaking artefacts and the artefact-free regions. However, in regions corresponding to dark streaking artefacts, the Siemens method does not seem to appropriately correct the tracer uptake while the proposed method consistently increased the uptake in the underestimated regions, thus bringing it to the expected level. This observation is corroborated by the experimental phantom study which demonstrates that the proposed method approaches the true activity concentration more closely. The proposed MAR method allows more accurate CT-based attenuation correction of PET images and prevents misinterpretation of tracer uptake, which might be biased owing to the propagation of bright and dark streaking artefacts from CT images to the PET data following the attenuation correction procedure. (orig.)

  15. Normal SUV values measured from NaF18- PET/CT bone scan studies.

    Directory of Open Access Journals (Sweden)

    Aung Zaw Win

    Full Text Available Cancer and metabolic bone diseases can alter the SUV. SUV values have never been measured from healthy skeletons in NaF18-PET/CT bone scans. The primary aim of this study was to measure the SUV values from normal skeletons in NaF18-PET/CT bone scans.A retrospective study was carried out involving NaF18- PET/CT bone scans that were done at our institution between January 2010 to May 2012. Our excluding criteria was patients with abnormal real function and patients with past history of cancer and metabolic bone diseases including but not limited to osteoporosis, osteopenia and Paget's disease. Eleven studies met all the criteria.The average normal SUVmax values from 11 patients were: cervical vertebrae 6.84 (range 4.38-8.64, thoracic vertebrae 7.36 (range 6.99-7.66, lumbar vertebrae 7.27 (range 7.04-7.72, femoral head 2.22 (range 1.1-4.3, humeral head 1.82 (range 1.2-2.9, mid sternum 5.51 (range 2.6-8.1, parietal bone 1.71 (range 1.3-2.4.According to our study, various skeletal sites have different normal SUV values. SUV values can be different between the normal bones and bones with tumor or metabolic bone disease. SUV can be used to quantify NaF-18 PET/CT studies. If the SUV values of the normal skeleton are known, they can be used in the characterization of bone lesions and in the assessment of treatment response to bone diseases.

  16. A method for extracting multi-organ from four-phase contrasted CT images based on CT value distribution estimation using EM-algorithm

    Science.gov (United States)

    Sakashita, Makiko; Kitasaka, Takayuki; Mori, Kensaku; Suenaga, Yasuhito; Nawano, Shigeru

    2007-03-01

    This paper presents a method for extracting multi-organs from four-phase contrasted CT images taken at different contrast timings (non-contrast, early, portal, and late phases). First, we apply a median filter to each CT image and align four-phase CT images by performing non-rigid volumetric image registration. Then, a three-dimensional joint histogram of CT values is computed from three-phase (early-, portal-, and late-) CT images. We assume that this histogram is a mixture of normal distributions corresponding to the liver, spleen, kidney, vein, artery, muscle, and bone regions. The EM algorithm is employed to estimate each normal distribution. Organ labels are assigned to each voxel using the mahalanobis distance measure. Connected component analysis is applied to correct the shape of each organ region. After that, the pancreas region is extracted from non-contrasted CT images in which other extracted organs and vessel regions are excluded. The EM algorithm is also employed for estimating the distribution of CT values inside the pancreas. We applied this method to seven cases of four-phase CT images. Extraction results show that the proposed method extracted multi-organs satisfactorily.

  17. Value of 18F-FDG PET/CT in diagnosing chronic Q fever in patients with central vascular disease

    NARCIS (Netherlands)

    Hagenaars, J. C J P; Wever, P. C.; Vlake, A. W.; Renders, N. H M; van Petersen, A. S.; Hilbink, M.; De Jager-Leclercq, M. G L; Moll, F. L.; Koning, O. H J; Hoekstra, C. J.

    2016-01-01

    Background: The aim of this study is to describe the value of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) in diagnosing chronic Q fever in patients with central vascular disease and the added value of18F-FDG PET/CT in the diagnostic combination s

  18. Transient hepatic attenuation difference (THAD) following transcatheter arterial chemoembolization for hepatic malignancy: changes on serial CT examinations

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Sung Ho; Yu, Jeong-Sik; Chung, Jin; Chung, Jae-Joon; Kim, Joo Hee; Kim, Ki Whang [Yonsei University College of Medicine, YongDong Severance Hospital, Department of Diagnostic Radiology and Research Institute of Radiological Science, Gangnam-Gu, Seoul (Korea)

    2008-08-15

    The purpose of this study was to investigate the natural history of transcatheter arterial chemoembolization (TACE)-induced, transient hepatic attenuation difference (THAD). Among the patients who underwent TACE for treatment of hepatocellular carcinomas during a 32-month period, 32 patients with 40 newly developed THADs defined as localized, transient, peripheral hepatic parenchymal enhancement during the hepatic arterial phase of dynamic CT (axial dimension, 1.9-8.8 cm; mean, 4.9 cm) in the vicinity of iodized-oil accumulation were subjected to a retrospective analysis of serial follow-up CT examinations. Among the 40 TACE-induced THADs, 18 (45%) and 9 (23%) were accompanied with arterial-portal venous fistula (APF) and portal venous stenosis (PVS), respectively, while 2 (5%) THADs showed both APF and PVS simultaneously. Thirty-eight (95%) THADs disappeared spontaneously during the follow-up period (range, 4-26 months; mean, 9 months), and 11 (29%) of them showed progressive atrophy of the corresponding hepatic parenchyma. Regardless of the presence of APF, 10 (91%) of 11 THADs of following parenchymal atrophy had shown PVSs (P<0.001). During the long-term follow-up period after TACE, almost all of the TACE-induced THADs spontaneously disappeared and either had or did not have corresponding parenchymal atrophy, which is strongly related to the presence of PVS. Understanding the nature of these CT features would be helpful for radiologists in determining the prognosis of the TACE-induced hepatic injuries as well as in distinguishing them from the recurrent tumour. (orig.)

  19. Bronchus-associated lymphoid tissue (BALT) lymphoma of the lung showing mosaic pattern of inhomogeneous attenuation on thin-section CT: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, In Jae; Kim, Sung Hwan; Koo, Soo Hyun; Kim, Hyun Beom; Hwang, Dae Hyun; Lee, Kwan Seop; Lee, Yul; Jang, Kee Taek; Kim, Duck Hwan [Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of)

    2000-09-01

    The authors present a case of histologically proven bronchus-associated lymphoid tissue (BALT) lymphoma of the lung in a patient with primary Sjogren's syndrome that manifested on thin-section CT scan as a mosaic pattern of inhomogeneous attenuation due to mixed small airway and infiltrative abnormalities.

  20. The effect of metal artefact reduction on CT-based attenuation correction for PET imaging in the vicinity of metallic hip implants : a phantom study

    NARCIS (Netherlands)

    Harnish, Roy; Prevrhal, Sven; Alavi, Abass; Zaidi, Habib; Lang, Thomas F.

    2014-01-01

    To determine if metal artefact reduction (MAR) combined with a priori knowledge of prosthesis material composition can be applied to obtain CT-based attenuation maps with sufficient accuracy for quantitative assessment of F-18-fluorodeoxyglucose uptake in lesions near metallic prostheses. A custom h

  1. The effect of metal artefact reduction on CT-based attenuation correction for PET imaging in the vicinity of metallic hip implants : a phantom study

    NARCIS (Netherlands)

    Harnish, Roy; Prevrhal, Sven; Alavi, Abass; Zaidi, Habib; Lang, Thomas F.

    To determine if metal artefact reduction (MAR) combined with a priori knowledge of prosthesis material composition can be applied to obtain CT-based attenuation maps with sufficient accuracy for quantitative assessment of F-18-fluorodeoxyglucose uptake in lesions near metallic prostheses. A custom

  2. High resolution micro-CT of low attenuating organic materials using large area photon-counting detector

    Science.gov (United States)

    Kumpová, I.; Vavřík, D.; Fíla, T.; Koudelka, P.; Jandejsek, I.; Jakůbek, J.; Kytýř, D.; Zlámal, P.; Vopálenský, M.; Gantar, A.

    2016-02-01

    To overcome certain limitations of contemporary materials used for bone tissue engineering, such as inflammatory response after implantation, a whole new class of materials based on polysaccharide compounds is being developed. Here, nanoparticulate bioactive glass reinforced gelan-gum (GG-BAG) has recently been proposed for the production of bone scaffolds. This material offers promising biocompatibility properties, including bioactivity and biodegradability, with the possibility of producing scaffolds with directly controlled microgeometry. However, to utilize such a scaffold with application-optimized properties, large sets of complex numerical simulations using the real microgeometry of the material have to be carried out during the development process. Because the GG-BAG is a material with intrinsically very low attenuation to X-rays, its radiographical imaging, including tomographical scanning and reconstructions, with resolution required by numerical simulations might be a very challenging task. In this paper, we present a study on X-ray imaging of GG-BAG samples. High-resolution volumetric images of investigated specimens were generated on the basis of micro-CT measurements using a large area flat-panel detector and a large area photon-counting detector. The photon-counting detector was composed of a 010× 1 matrix of Timepix edgeless silicon pixelated detectors with tiling based on overlaying rows (i.e. assembled so that no gap is present between individual rows of detectors). We compare the results from both detectors with the scanning electron microscopy on selected slices in transversal plane. It has been shown that the photon counting detector can provide approx. 3× better resolution of the details in low-attenuating materials than the integrating flat panel detectors. We demonstrate that employment of a large area photon counting detector is a good choice for imaging of low attenuating materials with the resolution sufficient for numerical simulations.

  3. Study on the application value of CT perfusion imaging in patients with hepatic carcinoma

    Institute of Scientific and Technical Information of China (English)

    Yu-Gang Zhou; Cheng-Zhou Yu; Xi-Qun Liu

    2016-01-01

    Objective:To research and discuss the application value of CT perfusion imaging in patients with hepatic carcinoma.Methods: A total of 47 patients with hepatic carcinoma in our hospital from Januarey 2014 to August 2015 were selected as study group; meanwhile the contemporaneous 47 patients with benign liver disease were selected as control group. Then the CT perfusion imaging parameters of hepatic carcinoma patients in control group and study group, and hepatic carcinoma patients with different types and stages in study group were respectively compared and the relationship between above indexes and hepatic carcinoma were analyzed by Logistic Analysis.Results:The BF, BV, HAI, MTT, PS and HAP levels in study group were all higher than that in control group, while the PVP level was lower than that in control group, and the detection results between hepatic carcinoma patients with different stages in study group also had obvious difference, statistical results of patients with higher stages were all worse than those of patients with lower stages, but the above statistical results among hepatic carcinoma patients with different types had no obvious difference, and the above detection indexes all had close relations with hepatic carcinoma by Logistic Analysis. Conclusion:The application value of CT perfusion imaging in patients with hepatic carcinoma was high, and it had active reaction value for the lesion blood flow of patients with hepatic carcinoma, and it also had high clinical value for the stages of disease.

  4. Value of oral effervescent powder administration for multidetector CT evaluation of esophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ringe, Kristina I., E-mail: ringe.kristina@mh-hannover.de [Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Meyer, Simone, E-mail: Meyer.simone.rad@mh-hannover.de [Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Ringe, Bastian P., E-mail: Ringe.bastian@mh-hannover.de [Department of General, Visceral and Transplantation Surgery, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Winkler, Michael, E-mail: Winkler.michael@mh-hannover.de [Department of General, Visceral and Transplantation Surgery, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Wacker, Frank, E-mail: Wacker.frank@mh-hannover.de [Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany); Raatschen, Hans-Juergen, E-mail: Raatschen.hans-juergen@mh-hannover.de [Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625 Hannover (Germany)

    2015-02-15

    Highlights: • Oral effervescent powder improves esophageal distension and wall assessment at CT. • This technique improves detection and T staging of esophageal cancer at CT. • It can be easily adopted in clinical routine in patients with esophageal pathology. - Abstract: Purpose: To assess the value of oral effervescent powder (EP) for evaluation of esophageal distension, and for detection and staging of esophageal cancer with contrast-enhanced CT. Materials and methods: 84 patients without esophageal pathology and 52 patients with histological confirmed diagnosis of esophageal cancer were included in this prospective IRB-approved study. Half of the patients in both groups received EP prior to CT. Esophageal distension was assessed by planimetry of the inner (IA) and outer area (OA). Two blinded readers evaluated the datasets separately with regard to diagnosis of esophageal cancer (yes/no) and staging (T0-T4), if applicable. Distension results were compared (t-Test). In patients with cancer sensitivity, specificity, NPV and PPV were calculated. CT staging results were compared to histopathology (Cohen-k). Results: IA and IA/OA were significantly larger after EP as compared to the group without EP (p < 0.05). Sensitivity, specificity, NPV and PPV for cancer detection cancer were as follows: 78%/78%, 98%/98%, 95%/95%, 87%/87% with EP; 60%/68%, 98%/98%, 94%/94%, 80%/83% without EP. Staging with EP was good (k = 0.84/0.67) and moderate without EP (k = 0.58/0.59). Conclusions: Administration of EP prior to CT results in good distension of the esophagus, and improves detection and staging of esophageal cancer, as compared to control studies without EP.

  5. Added value of arterial enhancement fraction color maps for the characterization of small hepatic low-attenuating lesions in patients with colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Mina Park

    Full Text Available To assess the added value of arterial enhancement fraction (AEF color maps for the differentiation of small metastases from hepatic benign lesions.We retrospectively analyzed 46 patients with colorectal cancer who underwent multiphasic liver CT imaging and had low-attenuating liver lesions smaller than 3 cm (123 total lesions; metastasis: benign = 32:91. AEF color maps of the liver were created from multiphasic liver CT images using dedicated software. Two radiologists independently reviewed multiphasic CT image sets alone and in combination with image sets with AEF color maps using a five-point scale. The additional diagnostic value of the color maps was assessed by means of receiver-operating characteristic (ROC analysis.The area under the ROC curve (Az increased when multiphasic CT images were combined with AEF color map analysis as compared with evaluation based only on multiphasic CT images (from 0.698 to 0.897 for reader 1, and from 0.825 to 0.945 for reader 2; P < 0.001 and 0.002, respectively. The increase Az was especially significant for lesions less than 1 cm (from 0.702 to 0.888 for reader 1, and from 0.768 to 0.958 for reader 2; P = 0.001 and P = 0.001, respectively. The mean AEF of tumor-adjacent parenchyma (35.07 ± 27.2 was significantly higher than that of tumor-free liver parenchyma (27.3 ± 20.6 (P = 0.04.AEF color mapping can improve the diagnostic performance for small hepatic metastases from colorectal cancer and may allow for the elimination of additional examinations.

  6. Attenuation properties and percentage depth dose of tannin-based Rhizophora spp. particleboard phantoms using computed tomography (CT) and treatment planning system (TPS) at high energy x-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Yusof, M. F. Mohd, E-mail: mfahmi@usm.my [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); School of Health Sciences, Universiti Sains Malaysia, 16150 Kota Bharu, Kelantan (Malaysia); Abdullah, R. [School of Health Sciences, Universiti Sains Malaysia, 16150 Kota Bharu, Kelantan (Malaysia); Tajuddin, A. A. [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Advanced Medical and Dental Institute, Universiti Sains Malaysia, 13200 Kepala Batas, Penang (Malaysia); Hashim, R. [School of Industrial Technologies, Universiti Sains Malaysia, 11800 Penang (Malaysia); Bauk, S. [Physics Section, School of Distance Education, Universiti Sains Malaysia, 11800 Penang (Malaysia)

    2016-01-22

    A set of tannin-based Rhizophora spp. particleboard phantoms with dimension of 30 cm x 30 cm was fabricated at target density of 1.0 g/cm{sup 3}. The mass attenuation coefficient of the phantom was measured using {sup 60}Co gamma source. The phantoms were scanned using Computed Tomography (CT) scanner and the percentage depth dose (PDD) of the phantom was calculated using treatment planning system (TPS) at 6 MV and 10 MV x-ray and compared to that in solid water phantoms. The result showed that the mass attenuation coefficient of tannin-based Rhizohora spp. phantoms was near to the value of water with χ{sup 2} value of 1.2. The measured PDD also showed good agreement with solid water phantom at both 6 MV and 10 MV x-ray with percentage deviation below 8% at depth beyond the maximum dose, Z{sub max}.

  7. Added value of using a CT coronal reformation to diagnose adnexal torsion

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Sung Il; Park, Hee Sun; Yim, Young Hee; Jeon, Hae Jeong; Yu, Mi Hye; Kim, Young Jun [Dept. of Radiology, Konkuk University School of Medicine, Research Institute of Medical Science, Seoul (Korea, Republic of); Jeong, Kyung Ah [Dept. of Obstetrics and Gynecology, School of Medicine, Ewha Womans University, Seoul (Korea, Republic of)

    2015-08-15

    To evaluate the increased value of using coronal reformation of a transverse computed tomography (CT) scan for detecting adnexal torsion. This study included 106 woman suspected of having adnexal torsion who underwent CT with coronal reformations and subsequent surgical exploration. Two readers independently recorded the CT findings, such as the thickening of a fallopian tube, twisting of the adnexal pedicle, eccentric smooth wall thickening of the torsed adnexal mass, eccentric septal thickening of the torsed adnexal mass, eccentric poor enhancement of the torsed adnexal mass, uterine deviation to the twisted side, ascites or infiltration of pelvic fat, and the overall impression of adnexal torsion with a transverse scan alone or combined with coronal reformation and a transverse scan. The areas under the receiver operating characteristic curves (AUCs), sensitivity, specificity, and positive predictive value were used to compare diagnostic performance. Fifty-two patients were confirmed to have adnexal torsion. The addition of coronal reformations to the transverse scan improved AUCs for readers 1 and 2 from 0.74 and 0.75 to 0.92 and 0.87, respectively, for detecting adnexal torsion (p < 0.001 and p = 0.004, respectively). Sensitivity of CT for detecting twisting of the adnexal pedicle increased significantly for readers 1 and 2 from 0.27 and 0.29 with a transverse scan alone to 0.79 and 0.77 with a combined coronal reformation and a transverse scan, respectively (p < 0.001 and p < 0.001, respectively). Use of a coronal reformation with transverse CT images improves detection of adnexal torsion.

  8. The value of {sup 18}F-FDG PET/CT in diagnosing infectious endocarditis

    Energy Technology Data Exchange (ETDEWEB)

    Kouijzer, Ilse J.E. [Radboud University Nijmegen Medical Centre, Department of Internal Medicine, P.O. Box 9101, Nijmegen (Netherlands); Vos, Fidel J. [Radboud University Nijmegen Medical Centre, Department of Internal Medicine, P.O. Box 9101, Nijmegen (Netherlands); Sint Maartenskliniek, Nijmegen (Netherlands); Janssen, Marcel J.R. [Radboud University Nijmegen Medical Centre, Department of Nuclear Medicine, Nijmegen (Netherlands); Dijk, Arie P.J. van [Radboud University Nijmegen Medical Centre, Department of Cardiology, Nijmegen (Netherlands); Oyen, Wim J.G. [Radboud University Nijmegen Medical Centre, Department of Nuclear Medicine, Nijmegen (Netherlands); Radboud University Nijmegen Medical Centre, Nijmegen Institute for Infection, Inflammation and Immunity (N4i), Nijmegen (Netherlands); Bleeker-Rovers, Chantal P. [Radboud University Nijmegen Medical Centre, Department of Internal Medicine, P.O. Box 9101, Nijmegen (Netherlands); Radboud University Nijmegen Medical Centre, Nijmegen Institute for Infection, Inflammation and Immunity (N4i), Nijmegen (Netherlands)

    2013-07-15

    Early detection of infectious endocarditis is challenging. For diagnosing infectious endocarditis, the revised Duke criteria are the gold standard. Evidence of endocardial involvement on echocardiography is a major criterion, but sensitivity and specificity of echocardiography are not optimal. Here we investigated the utility of {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT) to diagnose infectious endocarditis in patients with gram-positive bacteraemia. Seventy-two patients with gram-positive bacteraemia were prospectively included. Patients with a positive blood culture growing Staphylococcus aureus, Streptococcus species or Enterococcus species were eligible when a risk factor for developing metastatic infectious foci was present. Infectious endocarditis was defined according to the revised Duke criteria. All patients underwent {sup 18}F-FDG PET/CT and echocardiography. {sup 18}F-FDG uptake in or around the heart valves was evaluated independently by two nuclear medicine physicians. Sensitivity for diagnosing infectious endocarditis with {sup 18}F-FDG PET/CT was 39 % and specificity was 93 %. The positive predictive value was 64 % and negative predictive value was 82 %. The mortality rate in patients without infectious endocarditis and without increased {sup 18}F-FDG uptake in or around the heart valves was 18 %, and in patients without infectious endocarditis but with high {sup 18}F-FDG uptake in or around the heart valves the mortality rate was 50 % (p = 0.181). {sup 18}F-FDG PET/CT is currently not sufficiently adequate for the diagnosis of infectious endocarditis because of its low sensitivity. Improvements such as patient preparation with low carbohydrate-fat allowed diet and technical advances in the newest PET/CT scanners may increase sensitivity in future studies. (orig.)

  9. The value of 18F-FDG PET/CT in diagnosing infectious endocarditis.

    Science.gov (United States)

    Kouijzer, Ilse J E; Vos, Fidel J; Janssen, Marcel J R; van Dijk, Arie P J; Oyen, Wim J G; Bleeker-Rovers, Chantal P

    2013-07-01

    Early detection of infectious endocarditis is challenging. For diagnosing infectious endocarditis, the revised Duke criteria are the gold standard. Evidence of endocardial involvement on echocardiography is a major criterion, but sensitivity and specificity of echocardiography are not optimal. Here we investigated the utility of (18)F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT) to diagnose infectious endocarditis in patients with gram-positive bacteraemia. Seventy-two patients with gram-positive bacteraemia were prospectively included. Patients with a positive blood culture growing Staphylococcus aureus, Streptococcus species or Enterococcus species were eligible when a risk factor for developing metastatic infectious foci was present. Infectious endocarditis was defined according to the revised Duke criteria. All patients underwent (18)F-FDG PET/CT and echocardiography. (18)F-FDG uptake in or around the heart valves was evaluated independently by two nuclear medicine physicians. Sensitivity for diagnosing infectious endocarditis with (18)F-FDG PET/CT was 39% and specificity was 93%. The positive predictive value was 64% and negative predictive value was 82%. The mortality rate in patients without infectious endocarditis and without increased (18)F-FDG uptake in or around the heart valves was 18%, and in patients without infectious endocarditis but with high (18)F-FDG uptake in or around the heart valves the mortality rate was 50% (p = 0.181). (18)F-FDG PET/CT is currently not sufficiently adequate for the diagnosis of infectious endocarditis because of its low sensitivity. Improvements such as patient preparation with low carbohydrate-fat allowed diet and technical advances in the newest PET/CT scanners may increase sensitivity in future studies.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-06-01

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

  11. Diagnostic value of 18F-FDG PET/CT for cancer pain of peripheral nerves

    Directory of Open Access Journals (Sweden)

    Lei FANG

    2013-11-01

    Full Text Available Objective To observe the characteristics of cancer pain of the peripheral nerves on 18F-FDG PET/CT images, and explore the diagnostic value of 18F-FDG PET/CT for cancer pain of the peripheral nerves. Methods Imaging data of 18F-FDG PET/CT of 10 patients with cancer pain of the peripheral nerves confirmed by histopathology or long-term follow-up were analyzed retrospectively. The similarities and differences in PET/CT manifestations between the diseased side peripheral nerves and contralateral normal peripheral nerves were observed, and the maximum standardized uptake values (SUVmax were compared by paired t test with SPSS 17.0 software. Results Seventeen secondary malignant peripheral nerve lesions were found in 10 cases. On PET images, the lesions were found to spread along the plexus, nerve bundle or intervertebral foramen, and manifested as bundle-, root-hair- or nodule-like high 18F-FDG metabolic tissue, with the SUVmax as high as 6.67±3.24. The lesions on CT images manifested as bundle-, root-hair- or nodule-like soft tissue density shadows spreading along the nerve bundle or nerve root canal, and there was no clear border between the lesions and the surrounding soft and fat tissues. The contralateral normal peripheral nerves showed no abnormal images on 18F-FDG PET or CT, and the SUVmax was 1.19±0.48, which was significantly different from that of nerves on disease side (t=9.389, P<0.001. Conclusion 18F-FDG PET/CT can accurately show invasion and metastasis to the peripheral nerve of tumor, and it also can display the size, shape, distribution and tumor activity of the lesions, thus it is valuable for the diagnosis of cancer pain of the peripheral nerves. DOI: 10.11855/j.issn.0577-7402.2013.11.009

  12. Value of ultrasonography, Ct and MR imaging in the diagnosis of primary hyperparathyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Tziakouri, C. [Nicosia General Hospital (Cyprus). Dept. of Radiology; Eracleous, E. [Nicosia General Hospital (Cyprus). Dept. of Radiology; Skannavis, S. [Nicosia General Hospital (Cyprus). Dept. of Radiology; Pierides, A. [Nicosia General Hospital (Cyprus). Dept. of Nephrology; Symeonides, P. [Nicosia General Hospital (Cyprus). Dept of General Surgery; Gourtsoyiannis, N. [Univ. of Crete, Heraklion (Greece). Dept. of Radiology

    1996-09-01

    Purpose: To evaluate the significance of preoperative localization of abnormal parathyroid glands to the surgical outcome in patients with primary hyperparathyroidism. Material and Methods: Thirty-nine patients with primary hyperparathyroidism were studied preoperatively with US (39 patients), CT (30 patients) and MR imaging (18 patients). The overall diagnostic accuracy for US was 87%, CT 66% and MR 94%. In patients with a single parathyroid adenoma US was the most cost-effective localization technique with a detection rate of 96%. CT had a lower detection rate (78%) but was of particular value for fairly large ectopic adenomas in the root of the neck. MR imaging was a good confirmatory test (93%). In patients with multiple gland disease (primary hyperplasia and multiple adenomas), no single localization study alone was sufficient. Combination of all 3 studies, however, alerted the physician to the presence of disease in more than one gland in 87% of these patients. Conclusion: US, CT and MR imaging followed by surgery performed by an experienced surgeon provided good clinical results in 39 patients with primary hyperparathyroidism. Preoperative localization was especially useful in patients with primary parathyroid hyperplasia or multiple adenomas and in patients with ectopic parathyroid adenomas in the root of the neck. We recommend identification of all abnormal parathyroid glands prior to surgery. (orig.).

  13. Clinical value of CT three-dimensional imaging in diagnosing gastrointestinal tract diseases

    Institute of Scientific and Technical Information of China (English)

    Shao-Yin Duan; Dan-Tong Zhang; Qing-Chi Lin; Yan-Huan Wu

    2006-01-01

    AIM: To discuss the clinical value of CT three-dimensional (3-D) imaging in diagnosing gastrointestinal tract diseases.METHODS: Three-D imaging findings of 52 patients were retrospectively analyzed. Three-D imaging methods included shaded surface display (SSD), volume rendering (VR), virtual endoscopy (VE) and multiplanar reformatting (MPR). The diagnosis results of CT 3-D were evaluated by comparison with those of endoscopy and/or surgical finding.RESULTS: Fifty-two patients with gastrointestinal tract diseases were diagnosed by CT 3-D imaging, of whom 50 cases were correctly diagnosed and 2 were misdiagnosed. There were 33 cases of gastric diseases (27 with carcinoma, 5 with peptic ulcer and 1 with leiomyoma) and 19 large intestinal diseases (10 with colon carcinoma, 2 with carcinoma of the rectum, 5 with colon polypus and 2 with tuberculosis of the ileocecal junction). Twenty-two cases with prominent lesions (9 with subsequent hollow lesions), 20 with stenosis of cavity (8 with concomitant prominent lesions) and 10 with hollow lesions (5 with concomitant prominent lesions) were shown in 3-D images. The minimal lesion shown was 1.0 cm × 0.8 cm × 0.5 cm.CONCLUSION: CT 3-D imaging, a non-invasive examination without pain, can display clearly and directly the lesions of gastrointestinal tract with accurate location and high diagnosis accuracy. It is an important complementary technique to endoscopy.

  14. X-Ray CT of Highly-Attenuating Objects: 9- or 15- MV Spectra?

    Energy Technology Data Exchange (ETDEWEB)

    Stone, G; Trebes, J; Perry, R; Schneberk, D; Logan, C

    2005-08-29

    We imaged-highly attenuating test objects in three dimensions with 9-MV (at LLNL) and 15-MV (at Hill Air Force Base) x-ray spectra. While we used the same detector and motion control, there were differences that we could not control in the two radiography bays and in the sources. The results show better spatial resolution for the 9-MV spectrum and better contrast for the 15-MV spectrum. The 15-MV data contains a noise pattern that obfuscates the data. It is our judgment that if sufficient attention were given to design of the bay, beam dump, collimation, filtration and linac spot size; a 15-MV imaging system using a flat panel could be developed with spatial resolution of 5 lp/mm and contrastive performance better than we have demonstrated using a 9-MV spectrum.

  15. Influence of cone beam CT scanning parameters on grey value measurements at an implant site.

    Science.gov (United States)

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

    2013-01-01

    The aim of this study was to determine the grey value variation at the implant site with different scan settings, including field of view (FOV), spatial resolution, number of projections, exposure time and dose selections in two cone beam CT (CBCT) systems and to compare the results with those obtained from a multislice CT system. A partially edentulous human mandibular cadaver was scanned by three CT modalities: multislice CT (MSCT) (Philips, Best, the Netherlands), and two CBCT systems: (Accuitomo 170(®), Morita, Japan) and (NewTom 5G(®), QR, Verona, Italy). Using different scan settings 36 and 24 scans were obtained from the Accuitomo and the NewTom, respectively. The scans were converted to digital imaging and communications in medicine 3 format. The analysis of the data was performed using 3Diagnosys(®) software (v. 3.1, 3diemme, Cantù, Italy) and Geomagic studio(®) 2012 (Morrisville, NC). On the MSCT scan, one probe designating the site for pre-operative implant placement was inserted. The inserted probe on MSCT was transformed to the same region on each CBCT scan using a volume-based three-dimensional registration algorithm. The mean voxel grey value of the region around the probe was derived separately for each CBCT. The influence of scanning parameters on the measured mean voxel grey values was assessed. Grey values in both CBCT systems significantly deviated from Hounsfield unit values measured with MSCT (p = 0.0001). In both CBCT systems, scan FOV and spatial resolution selections had a statistically significant influence on grey value measurements (p = 0.0001). The number of projections selection had a statistically significant influence in the Accuitomo system (p = 0.0001) while exposure time and dose selections had no statistically significant influence on grey value measurements in the NewTom (p = 0.43 and p = 0.37, respectively). Grey-level values from CBCT images are influenced by device and scanning settings.

  16. Value and clinical application of orthopedic metal artifact reduction algorithm in CT scans after orthopedic metal implantation

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yi; Pan, Shinong; Zhao, Xudong; Guo, Wenli; He, Ming; Guo, Qiyong [Shengjing Hospital of China Medical University, Shenyang (China)

    2017-06-15

    To evaluate orthopedic metal artifact reduction algorithm (O-MAR) in CT orthopedic metal artifact reduction at different tube voltages, identify an appropriate low tube voltage for clinical practice, and investigate its clinical application. The institutional ethical committee approved all the animal procedures. A stainless-steel plate and four screws were implanted into the femurs of three Japanese white rabbits. Preoperative CT was performed at 120 kVp without O-MAR reconstruction, and postoperative CT was performed at 80–140 kVp with O-MAR. Muscular CT attenuation, artifact index (AI) and signal-to-noise ratio (SNR) were compared between preoperative and postoperative images (unpaired t test), between paired O-MAR and non-O-MAR images (paired Student t test) and among different kVp settings (repeated measures ANOVA). Artifacts' severity, muscular homogeneity, visibility of inter-muscular space and definition of bony structures were subjectively evaluated and compared (Wilcoxon rank-sum test). In the clinical study, 20 patients undertook CT scan at low kVp with O-MAR with informed consent. The diagnostic satisfaction of clinical images was subjectively assessed. Animal experiments showed that the use of O-MAR resulted in accurate CT attenuation, lower AI, better SNR, and higher subjective scores (p < 0.010) at all tube voltages. O-MAR images at 100 kVp had almost the same AI and SNR as non-O-MAR images at 140 kVp. All O-MAR images were scored ≥ 3. In addition, 95% of clinical CT images performed at 100 kVp were considered satisfactory. O-MAR can effectively reduce orthopedic metal artifacts at different tube voltages, and facilitates low-tube-voltage CT for patients with orthopedic metal implants.

  17. Diagnostic value of multiplanar reconstruction in CT recognition of lumbar spinal disorders

    Energy Technology Data Exchange (ETDEWEB)

    Im, S. K.; Choi, J. H.; Kim, C. H.; Sohn, M. H.; Lim, K. Y.; Choi, K. C. [Chonbuk National University College of Medicine, Chonju (Korea, Republic of)

    1984-12-15

    The computer tomography is useful in evaluation of bony structures and adjacent soft tissues of the lumbar spine. Recently, the multiplanar reconstruction of lumbar spine of CT of significant value for the anatomical localization and for the myelographic and surgical correlation. We observed 177 cases of lumbar spine CT, who complains of spinal symptom, during the period from Dec. 1982 to Aug. 1984. The results were as follows: 1. The sex distribution of cases were 113 males and 44 females. The CT diagnosis showed 152 cases of herniated lumbar disc, 15 cases of degenerative disease, 5 cases of spine tbc., 3 cases of spine trauma and 2 cases of meningocele. 2. CT findings of herniated disc were as follows: focal protrusion of posterior disc margin and obliteration of anterior epidural fat in all cases, indentation on dural sac in 92 cases (60.5%) soft tissue mass in epidural fat in 85 cases (55.9%), compression or displacement of nerve root sheath in 22 cases(14.4%). 3. Sites of herniated lumbar disc were at L4-L5 level in 100 cases(59.1%) and at L5-S1 level in 65 cases (38.4%). Location of it were central type in 70 cases(41.1%), left-central type in 46 cases (27.2%), right-central type in 44 cases(26.0%) and lateral type in 9 cases (5.1%). 4. The sagittal reconstruction images were helpful in evaluating neural foramina, size of disc bluge into spinal canal, especially at L5-S1, and patients with spondylolisthesis. The coronal reconstruction images were the least informative, although they contributed to the evaluation of lumbar nerve roots of course, the axial CT scans were the most sensitive and specific.

  18. The added value of PET/Ce-CT/DW-MRI fusion in assessment of hepatic focal lesions: PET/Ce-CT/DW-MRI fusion in hepatic focal lesion.

    Science.gov (United States)

    Salem, Shahenda; Houseni, Mohamed; Zidan, Lamiaa; Kandil, Ahmed

    2015-07-01

    The liver hosts a variety of benign and malignant tumors. Accurate diagnosis can be challenging in certain cases, especially in patients with a history of malignancy or in those with underlying liver pathology, such as cirrhosis. To evaluate the added clinical value of multi-modality liver imaging utilizing PET/Ce-CT/DW-MRI for characterization of hepatic focal lesions (HFL) and compare it with each diagnostic modality when interpreted alone. The study included 35 patients with HFL. They were 7 females & 28 males; their age ranged from 41 to 78years, all patients underwent PET/Ce-CT and DW-MRI scans. Ce-CT, PET and DW-MR images were reviewed independently, and then combined PET/Ce-CT, PET/DW-MRI and PET/Ce-CT/DW-MRI scans were analyzed. The results were correlated with histopathology or clinical/imaging follow-up. The 35 patients had 98 focal lesions. Fifty-three lesions were finally diagnosed as primary hepatocellular carcinoma, 18 lesions were metastases, 7 lesions were lymphoma and 20 lesions were benign. On a patient based analysis; the sensitivity, specificity, PPV, NPV and accuracy were 100%, 67%, 94%, 100% and 94% for PET/Ce-CT compared to 97%, 83%, 97%, 83% and 94 % for DW-MRI, respectively. Combined PET/Ce-CT/DW-MR scans raise those parameters up to 100%. On a lesion based analysis; the sensitivity, specificity, PPV, NPV and accuracy were 94%, 75%, 94%, 75%, 90% for PET/Ce-CT compared to 94%, 95%, 99%, 97% and 94 % for DW-MRI, respectively. All these parameters were 100 % with PET/Ce-CT/DW-MRI. The addition of DW-MRI to PET/Ce-CT is valuable in the characterization of hepatic focal lesions. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Fever of unknown origin: A value of {sup 18}F-FDG-PET/CT with integrated full diagnostic isotropic CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ferda, Jiri [Department of Nuclear Medicine, Charles University Medical School and Teaching Hospital, Plzen (Czech Republic); Radiodiagnostic Clinic, Charles University Medical School and Teaching Hospital, Plzen (Czech Republic)], E-mail: ferda@fnplzen.cz; Ferdova, Eva [Department of Nuclear Medicine, Charles University Medical School and Teaching Hospital, Plzen (Czech Republic); Radiodiagnostic Clinic, Charles University Medical School and Teaching Hospital, Plzen (Czech Republic); Zahlava, Jan [Department of Nuclear Medicine, Charles University Medical School and Teaching Hospital, Plzen (Czech Republic); Matejovic, Martin [Ist Internal Department, Charles University Medical School and Teaching Hospital, Plzen (Czech Republic); Kreuzberg, Boris [Radiodiagnostic Clinic, Charles University Medical School and Teaching Hospital, Plzen (Czech Republic)

    2010-03-15

    Aim: The aim of presented work is to evaluate the clinical value of {sup 18}F-FDG-PET/CT in patients with fever of unknown origin (FUO) and to compare PET/CT finding with the results of the following investigation. Material and method: 48 patients (24 men, 24 women, mean age 57.6 years with range 15-89 years) underwent {sup 18}F-FDG-PET/CT due to the fever of unknown origin. All examinations were performed using complex PET/CT protocol combined PET and whole diagnostic contrast enhanced CT with sub-millimeter spatial resolution (except patient with history of iodine hypersensitivity or sever renal impairment). CT data contained diagnostic images reconstructed with soft tissue and high-resolution algorithm. PET/CT finding were compared with results of biopsies, immunology, microbiology or autopsy. Results: The cause of FUO was explained according to the PET/CT findings and followed investigations in 44 of 48 cases-18 cases of microbial infections, nine cases of autoimmune inflammations, four cases of non-infectious granulomatous diseases, eight cases of malignancies and five cases of proved immunity disorders were found. In 46 cases, the PET/CT interpretation was correct. Only in one case, the cause was overlooked and the uptake in atherosclerotic changes of arteries was misinterpreted as vasculitis in the other. The reached sensitivity was 97% (43/44), and specificity 75% (3/4) respectively. Conclusion: In patients with fever of unknown origin, {sup 18}F-FDG-PET/CT might enable the detection of its cause.

  20. Standardized uptake values for [{sup 18}F] FDG in normal organ tissues: Comparison of whole-body PET/CT and PET/MRI

    Energy Technology Data Exchange (ETDEWEB)

    Heusch, Philipp [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, D-45147 Essen (Germany); Buchbender, Christian, E-mail: Christian.buchbender@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Beiderwellen, Karsten; Nensa, Felix [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, D-45147 Essen (Germany); Hartung-Knemeyer, Verena [Univ Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, D-45147 Essen (Germany); Lauenstein, Thomas C. [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, D-45147 Essen (Germany); Bockisch, Andreas [Univ Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, D-45147 Essen (Germany); Forsting, Michael [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, D-45147 Essen (Germany); Antoch, Gerald; Heusner, Till A. [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany)

    2013-05-15

    Purpose: To compare maximum and mean standardized uptake values (SUVmax/mean) of normal organ tissues derived from [{sup 18}F]-fluoro-desoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) using MR attenuation correction (MRAC) (DIXON-based 4-segment μ-map) with [{sup 18}F]-FDG positron emission tomography/computed tomography (PET/CT) using CT-based attenuation correction (CTAC). Methods and materials: In 25 oncologic patients (15 men, 10 women; age 57 ± 13 years) after routine whole-body FDG-PET/CT (60 min after injection of 290 ± 40 MBq [{sup 18}F]-FDG) a whole-body PET/MRI was performed (Magnetom Biograph mMR™, Siemens Healthcare, Erlangen, Germany). Volumes of interest of 1.0 cm{sup 3} were drawn in 7 physiological organ sites in MRAC-PET and the corresponding CTAC-PET images manually. Spearman correlation coefficients were calculated to compare MRAC- and CTAC based SUV values; Wilcoxon-Matched-Pairs signed ranks test was performed to test for potential differences. Results: The mean delay between FDG-PET/CT and PET/MRI was 92 ± 18 min. Excellent correlations of SUV values were found for the heart muscle (SUVmax/mean: R = 0.97/0.97); reasonably good correlations were found for the liver (R = 0.65/0.72), bone marrow (R = 0.42/0.41) and the SUVmax of the psoas muscle (R = 0.41). For subcutaneous fat, the correlation coefficient was 0.66 for SUVmean (p < 0.05). Correlations between MRAC and CTAC were non-significant for SUVmean of the psoas muscle, SUVmax of subcutaneous fat, SUVmax and SUVmean of the lungs, SUVmax and SUVmean of the blood-pool. The median SUVmax and SUVmean in MRAC-PET were lower than the respective CTAC values in all organs (p < 0.05) but heart (SUVmax) and the bone marrow (SUVmean). Conclusion: In conclusion, in oncologic patients examined with PET/CT and PET/MRI SUVmax and SUVmean values generally correlate well in normal organ tissues, except the lung, subcutaneous fat and the blood pool. SUVmax and

  1. The value of CT for the diagnosis of acute diverticulitis; Der Stellenwert der CT in der Akutdiagnostik der Divertikulitis

    Energy Technology Data Exchange (ETDEWEB)

    Rotert, H.; Noeldge, G.; Richter, G.M.; Duex, M. [Abteilung fuer Radiodiagnostik, Universitaetsklinikum Heidelberg (Germany); Encke, J. [Medizinische Klinik IV, Universitaetsklinikum Heidelberg (Germany)

    2003-01-01

    In acute diverticulitis accurate diagnosis and staging are mandatory to decide on the treatment of the patient.The impact of computed tomography (CT) on the treatment of acute diverticulitis will be discussed.Material and Method CT is performed after distension of the distal colon by means of positive,water-soluble contrast media to depict intestinal perforation or penetration. Then intravenous contrast material is administered and spiral scanning is repeated to judge enhancement patterns of the abdominal structures/organs especially of the intestinal wall and to diagnose abscess formation. CT-morphologies of different stages of acute diverticulitis will be described. CT imaging is the only diagnostic method that in case of an acute diverticulitis combines safety with accuracy. On the one hand, it is fast and therefore safe with respect to patient control and on the other hand, it allows accurate staging of the inflammatory process reaching a sensitivity and specificity of up to 100%, each. CT is an appropriate tool to diagnose acute diverticulitis complicated by abscess formation, intestinal penetration or perforation and therefore has direct impact on the treatment of the patient.Discussion If acute diverticulitis is suspected CT is the method of choice for imaging because of its high impact on the choice of therapy and on the management of complications. (orig.) [German] Zielsetzung Bei der akuten Divertikulitis entscheidet eine exakte Stadieneinteilung der Erkrankung ueber das therapeutische Vorgehen.Die Diagnostik mittels Computertomographie (CT) wird der klinischen Einteilung der akuten Divertikulitis und den sich daraus ableitenden therapeutischen Strategien gegenuebergestellt.Material und Methode Die Durchfuehrung der CT bei Verdacht auf akute Divertikulitis erfolgt nach transanaler, intraluminaler Kontrastierung des Darms mit positivem wasserloeslichem Kontrastmittel, um eine Penetration oder Darmperforation nachzuweisen. Anschliessend erfolgt eine

  2. Multislice Analysis of Blood Flow Values in CT Perfusion Studies of Lung Cancer

    Science.gov (United States)

    Malavasi, Silvia; Barone, Domenico; Gavelli, Giampaolo

    2017-01-01

    Objectives. Tumour heterogeneity represents a key issue in CT perfusion (CTp), where all studies are usually based on global mean or median values of perfusion maps, often computed on whole tumour. We sought to determine whether, and to what extent, such global values can be representative of tumour heterogeneity, with respect to single slices, and could be used for therapy assessment. Materials and Methods. Twelve patients with one primary non-small cell lung cancer lesion were enrolled in this study, for a total amount of 26 CTp examinations and 118 slices. Mean and median blood flow (BF) values, calculated voxel-based, were computed on each slice and the whole tumour. To measure functional heterogeneity, entropy was calculated on BF values as well. Results. Most of the slices were not represented by the global BF values computed on the whole tumour. In addition, there are a number of lesions having equivalent global BF values, but they are composed of slices having very different heterogeneity distributions, that is, entropy values. Conclusions. Global mean/median BF values of the single slices separately should be considered for clinical assessment, only if interpreted through entropy computed on BF values. The numerical equivalence between global BF values of different lesions may correspond to different clinical status, thus inducing possible errors in choice of therapy when considering global values only. PMID:28164118

  3. Prognostic value of FDG PET/CT in head and neck squamous cell carcinomas

    Directory of Open Access Journals (Sweden)

    Dequanter D

    2015-08-01

    Full Text Available D Dequanter,1,2 M Shahla,2 C Aubert,2 Y Deniz,2 P Lothaire2 1Department of Oncology, Laboratory of Experimental Radiotherapy, KU Leuven, Leuven, Belgium; 2Head and Neck Department, Hôpital André Vésale, CHU de Charleroi, Montigny le Tilleul, Belgium Introduction: The purpose of this study was to evaluate the use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT to identify the presence of cervical lymph nodes metastases and extracapsular spread with histologic correlations in head and neck squamous cell carcinoma.Methods: The medical records of 54 patients who underwent 18F-FDG PET/CT for head and neck squamous cell carcinoma before surgery were reviewed. Receiver operating characteristic (ROC analysis was performed to differentiate patients with cervical lymph node metastasis from those without lymph node metastasis. The same statistical analysis was done to differentiate cervical lymph nodes with extracapsular spread from those without extracapsular spread.Results: Metastatic disease was diagnosed histologically in 49% (26 of 54 of the patients. Extracapsular spread was present in ten of the 54 patients (19%. When ROC curve analysis and maximum standardized uptake (SUVmax values were used to detect cervical lymph node metastasis, the area under the ROC curve was 0.96 and the optimal cutoff value for SUVmax was 4.05 based on ROC curve analysis. The sensitivity and specificity of SUVmax for the detection of cervical lymph node metastasis using this cutoff point were 92% and 88%, respectively. When ROC curve analysis and SUVmax values were used in order to detect extracapsular spread, the area under the ROC curve was 0.86, and the optimal cutoff value for SUVmax was 4.15 based on ROC curve analysis. Using this cutoff value, the sensitivity and specificity of SUVmax for the detection of extracapsular spread were 83% and 88%, respectively.Conclusion: In our study, a median 18F-FDG PET/CT SUVmax cutoff

  4. Fast analytical approach of application specific dose efficient spectrum selection for diagnostic CT imaging and PET attenuation correction

    Science.gov (United States)

    Rui, Xue; Jin, Yannan; FitzGerald, Paul F.; Wu, Mingye; Alessio, Adam M.; Kinahan, Paul E.; De Man, Bruno

    2016-11-01

    Computed tomography (CT) has been used for a variety of applications, two of which include diagnostic imaging and attenuation correction for PET or SPECT imaging. Ideally, the x-ray tube spectrum should be optimized for the specific application to minimize the patient radiation dose while still providing the necessary information. In this study, we proposed a projection-based analytic approach for the analysis of contrast, noise, and bias. Dose normalized contrast to noise ratio (CNRD), inverse noise normalized by dose (IND) and bias are used as evaluation metrics to determine the optimal x-ray spectrum. Our simulation investigated the dose efficiency of the x-ray spectrum ranging from 40 kVp to 200 kVp. Water cylinders with diameters of 15 cm, 24 cm, and 35 cm were used in the simulation to cover a variety of patient sizes. The effects of electronic noise and pre-patient copper filtration were also evaluated. A customized 24 cm CTDI-like phantom with 13 mm diameter inserts filled with iodine (10 mg ml-1), tantalum (10 mg ml-1), water, and PMMA was measured with both standard (1.5 mGy) and ultra-low (0.2 mGy) dose to verify the simulation results at tube voltages of 80, 100, 120, and 140 kVp. For contrast-enhanced diagnostic imaging, the simulation results indicated that for high dose without filtration, the optimal kVp for water contrast is approximately 100 kVp for a 15 cm water cylinder. However, the 60 kVp spectrum produces the highest CNRD for bone and iodine. The optimal kVp for tantalum has two selections: approximately 50 and 100 kVp. The kVp that maximizes CNRD increases when the object size increases. The trend in the CTDI phantom measurements agrees with the simulation results, which also agrees with previous studies. Copper filtration improved the dose efficiency for water and tantalum, but reduced the iodine and bone dose efficiency in a clinically-relevant range (70-140 kVp). Our study also shows that for CT-based attenuation

  5. Inter-comparison of {sup 18}F-FDG PET/CT standardized uptake values in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hoon Hee [Department of Nuclear Medicine, Severance Hospital, Yonsei University Health System, Seoul 120-752 (Korea, Republic of); Park, Dae Sung [Department of Chonnam National University Hospital Heart Research Center, Gwangju 501-757 (Korea, Republic of); Kweon, Dae Cheol [Department of Radiology, Shinheung College, Kyungki 480-701 (Korea, Republic of); Lee, Sang Bock [Department of Radiology, Nambu University, 864-1, Wolgye-dong, Gwangsan-gu, Gwangju 506-706 (Korea, Republic of); Oh, Ki Baek; Lee, Jong Doo [Department of Nuclear Medicine, Severance Hospital, Yonsei University Health System, Seoul 120-752 (Korea, Republic of); Jin, Gye Hwan, E-mail: ghjin@nambu.ac.k [Department of Radiology, Nambu University, 864-1, Wolgye-dong, Gwangsan-gu, Gwangju 506-706 (Korea, Republic of)

    2011-01-15

    The number of PET/CT tests for diagnosing and treating tumors are increasing every year, and thus it is considered necessary to compare PET/CT images among medical institutions or among different PET/CT systems within the same medical institution. We present to get the variation of standardized uptake values (SUV) among PET/CT systems, to derive an SUV calibration table that enables quantitative comparison of PET/CT systems, and to test the usefulness of the calibration table through comparing patient's SUV with the SUV calibration table. The correlation coefficients that inter-compared the calibration constants of normal patients and the calibration constants of the mean standardized uptake value with the calibration constants of the standardized uptake value of phantom are 0.88938 (P<0.0001).

  6. Effects of CT-based attenuation correction of rat microSPECT images on relative myocardial perfusion and quantitative tracer uptake

    Energy Technology Data Exchange (ETDEWEB)

    Strydhorst, Jared H., E-mail: jared.strydhorst@gmail.com; Ruddy, Terrence D.; Wells, R. Glenn [Cardiac Imaging, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, Ontario K1Y 4W7 (Canada)

    2015-04-15

    Purpose: Our goal in this work was to investigate the impact of CT-based attenuation correction on measurements of rat myocardial perfusion with {sup 99m}Tc and {sup 201}Tl single photon emission computed tomography (SPECT). Methods: Eight male Sprague-Dawley rats were injected with {sup 99m}Tc-tetrofosmin and scanned in a small animal pinhole SPECT/CT scanner. Scans were repeated weekly over a period of 5 weeks. Eight additional rats were injected with {sup 201}Tl and also scanned following a similar protocol. The images were reconstructed with and without attenuation correction, and the relative perfusion was analyzed with the commercial cardiac analysis software. The absolute uptake of {sup 99m}Tc in the heart was also quantified with and without attenuation correction. Results: For {sup 99m}Tc imaging, relative segmental perfusion changed by up to +2.1%/−1.8% as a result of attenuation correction. Relative changes of +3.6%/−1.0% were observed for the {sup 201}Tl images. Interscan and inter-rat reproducibilities of relative segmental perfusion were 2.7% and 3.9%, respectively, for the uncorrected {sup 99m}Tc scans, and 3.6% and 4.3%, respectively, for the {sup 201}Tl scans, and were not significantly affected by attenuation correction for either tracer. Attenuation correction also significantly increased the measured absolute uptake of tetrofosmin and significantly altered the relationship between the rat weight and tracer uptake. Conclusions: Our results show that attenuation correction has a small but statistically significant impact on the relative perfusion measurements in some segments of the heart and does not adversely affect reproducibility. Attenuation correction had a small but statistically significant impact on measured absolute tracer uptake.

  7. Factors influencing the robustness of P-value measurements in CT texture prognosis studies

    Science.gov (United States)

    McQuaid, Sarah; Scuffham, James; Alobaidli, Sheaka; Prakash, Vineet; Ezhil, Veni; Nisbet, Andrew; South, Christopher; Evans, Philip

    2017-07-01

    Several studies have recently reported on the value of CT texture analysis in predicting survival, although the topic remains controversial, with further validation needed in order to consolidate the evidence base. The aim of this study was to investigate the effect of varying the input parameters in the Kaplan-Meier analysis, to determine whether the resulting P-value can be considered to be a robust indicator of the parameter’s prognostic potential. A retrospective analysis of the CT-based normalised entropy of 51 patients with lung cancer was performed and overall survival data for these patients were collected. A normalised entropy cut-off was chosen to split the patient cohort into two groups and log-rank testing was performed to assess the survival difference of the two groups. This was repeated for varying normalised entropy cut-offs and varying follow-up periods. Our findings were also compared with previously published results to assess robustness of this parameter in a multi-centre patient cohort. The P-value was found to be highly sensitive to the choice of cut-off value, with small changes in cut-off producing substantial changes in P. The P-value was also sensitive to follow-up period, with particularly noisy results at short follow-up periods. Using matched conditions to previously published results, a P-value of 0.162 was obtained. Survival analysis results can be highly sensitive to the choice in texture cut-off value in dichotomising patients, which should be taken into account when performing such studies to avoid reporting false positive results. Short follow-up periods also produce unstable results and should therefore be avoided to ensure the results produced are reproducible. Previously published findings that indicated the prognostic value of normalised entropy were not replicated here, but further studies with larger patient numbers would be required to determine the cause of the different outcomes.

  8. The additional value of CT images interpretation in the differential diagnosis of benign vs. malignant primary bone lesions with 18F-FDG-PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Strobel, K.; Stumpe, K.D.M.; Hany, T.F.; Mende, K.; Veit-Haibach, P.; Schulthess, G.K. von [University Hospital Zurich, Division of Nuclear Medicine, Department of Medical Radiology, Zurich (Switzerland); Exner, U.E. [University Hospital Balgrist, Department of Orthopedic Surgery, Zurich (Switzerland); Bode, B. [University Hospital Zurich, Institute of Surgical Pathology, Zurich (Switzerland); Hodler, Juerg [University Hospital Balgrist, Department of Radiology, Zurich (Switzerland)

    2008-11-15

    To evaluate the value of a dedicated interpretation of the CT images in the differential diagnosis of benign vs. malignant primary bone lesions with 18fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT). In 50 consecutive patients (21 women, 29 men, mean age 36.9, age range 11-72) with suspected primary bone neoplasm conventional radiographs and 18F-FDG-PET/CT were performed. Differentiation of benign and malignant lesions was separately performed on conventional radiographs, PET alone (PET), and PET/CT with specific evaluation of the CT part. Histology served as the standard of reference in 46 cases, clinical, and imaging follow-up in four cases. According to the standard of reference, conventional 17 lesions were benign and 33 malignant. Sensitivity, specificity, and accuracy in assessment of malignancy was 85%, 65% and 78% for conventional radiographs, 85%, 35% and 68% for PET alone and 91%, 77% and 86% for combined PET/CT. Median SUV{sub max} was 3.5 for benign lesions (range 1.6-8.0) and 5.7 (range 0.8-41.7) for malignant lesions. In eight patients with bone lesions with high FDG-uptake (SUV{sub max} {>=} 2.5) dedicated CT interpretation led to the correct diagnosis of a benign lesion (three fibrous dysplasias, two osteomyelitis, one aneurysmatic bone cyst, one fibrous cortical defect, 1 phosphaturic mesenchymal tumor). In four patients with lesions with low FDG-uptake (SUV{sub max} < 2.5) dedicated CT interpretation led to the correct diagnosis of a malignant lesion (three chondrosarcomas and one leiomyosarcoma). Combined PET/CT was significantly more accurate in the differentiation of benign and malignant lesions than PET alone (p =.039). There was no significant difference between PET/CT and conventional radiographs (p =.625). Dedicated interpretation of the CT part significantly improved the performance of FDG-PET/CT in differentiation of benign and malignant primary bone lesions compared to PET alone. PET/CT more commonly

  9. The value of quantitative analysis in (18)F-NaF PET/CT.

    Science.gov (United States)

    Lapa, P; Marques, M; Costa, G; Lima, J P

    To evaluate the ability of SUVmax to differentiate bone metastases from degenerative lesions, blastic from lytic metastases, as well as to determine the correlation between SUVmax with (18)F-NaF and with (18)F-FDG. A review was performed on 115 (18)F-NaF PET/CT studies. Of the 64 patients with bone metastases, 49 (39 women, 10 men, 61±12 years (16-81)), in whom the PET/CT supported the diagnosis of bone metastases, were selected for analysis. A record was made of the SUVmax of a maximum of ten metastases in each patient (total 172: 141 blastic, 31 lytic), as well as four degenerative lesions (total 188) with the greatest (18)F-NaF uptake intensity. Of the 49 patients analyzed, 43 also had a (18)F-FDG PET/CT performed in which a record was made of the SUVmax values for (18)F-FDG calculated in the locations corresponding to the bone metastases observed in the (18)F-NaF PET/CT: 128 metastases (106 blastic, 22 lytic). The mean of the SUVmax values was significantly higher in metastases than in degenerative lesions, 26.8±17.3 vs. 15.3±6.3 (P<0.001) and in blastic than in lytic metastases, 27.9±18.3 vs. 22.1±11.3 (P=0.03). A SUVmax value above 42 always represented metastases, with all values above 49 representing blastic metastases. Using the SUVmax values, it was possible to predict the occurrence of metastases (AUC=0.723; P<0.001; 95% CI=0.671-0.776). The mean of the SUVmax with (18)F-NaF was significantly higher in blastic metastases (27.9±18.3 vs. 22.1±11.3, P=0.03), whereas with (18)F-FDG it was significantly higher in lytic ones (3.9±3.4 vs. 9.6±3.3; P<0.01). SUVmax can contribute to the differentiation of metastases from degenerative lesions, and blastic from lytic metastases. Copyright © 2016 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  10. Prognostic value of interim and restaging PET/CT in Hodgkin lymphoma. Results of the CHEAP (Chemotherapy Effectiveness Assessment by PET/CT) study - long term observation.

    Science.gov (United States)

    Miltenyi, Z; Barna, S; Garai, I; Simon, Z; Jona, A; Magyari, F; Gergely, M; Nagy, Z; Keresztes, K; Pettendi, P; Illes, A

    2015-01-01

    Very few studies have determined the prognostic value of interim and restaging PET/CT in patients with Hodgkin lymphoma using current standard of care therapy outside clinical trials. We analyzed the effect of the results of interim and restaging PET/CT on the survival (overall- and relapse-free) in patients who received standard first-line treatment based on the stage of disease and risk factors. We investigated the differences between the relapse and non-relapse groups based on the clinical pathological characteristics of patients who had positive interim PET/CT results.Between January 1, 2007 and December 31, 2011, the staging, interim and restaging PET/CT scans of patients with Hodgkin lymphoma were analyzed. The Deauville criteria were used for the evaluation of interim PET/CT scans. One hundred and thirteen Hodgkin lymphoma patients underwent staging, interim and restaging PET/CT scans. None of the therapy was modified based on the interim PET/CT results. The median follow-up time was 43.5 months. A total of 62 early stage patients and 51 advanced stage patients were identified. The five-year overall survival rates were 93.4% in the interim PET negative group and 58% in the interim PET positive group (pinterim PET positive group, patients over 40 years of age had a significantly higher probability of relapse (p=0.057).The routine clinical use of interim PET/CT is highly recommended based on our investigation. However, patients with positive interim PET/CT results required frequent additional evaluations.

  11. Detection of hemorrhage source: the diagnostic value of post-mortem CT-angiography.

    Science.gov (United States)

    Palmiere, C; Binaghi, S; Doenz, F; Bize, P; Chevallier, C; Mangin, P; Grabherr, S

    2012-10-10

    The aim of this study was to compare the diagnostic value of post-mortem computed tomography angiography (PMCTA) to conventional, ante-mortem computed tomography (CT)-scan, CT-angiography (CTA) and digital subtraction angiography (DSA) in the detection and localization of the source of bleeding in cases of acute hemorrhage with fatal outcomes. The medical records and imaging scans of nine individuals who underwent a conventional, ante-mortem CT-scan, CTA or DSA and later died in the hospital as a result of an acute hemorrhage were reviewed. Post-mortem computed tomography angiography, using multi-phase post-mortem CTA, as well as medico-legal autopsies were performed. Localization accuracy of the bleeding was assessed by comparing the diagnostic findings of the different techniques. The results revealed that data from ante-mortem and post-mortem radiological examinations were similar, though the PMCTA showed a higher sensitivity for detecting the hemorrhage source than did ante-mortem radiological investigations. By comparing the results of PMCTA and conventional autopsy, much higher sensitivity was noted in PMCTA in identifying the source of the bleeding. In fact, the vessels involved were identified in eight out of nine cases using PMCTA and only in three cases through conventional autopsy. Our study showed that PMCTA, similar to clinical radiological investigations, is able to precisely identify lesions of arterial and/or venous vessels and thus determine the source of bleeding in cases of acute hemorrhages with fatal outcomes.

  12. The diagnostic value of sacroiliac CT for detecting early changes of ankylosing spondylitis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ju Hyun; Park, Ji Seon; Ryu, Kyung Nam [Kyunghee University Medical Center, Seoul (Korea, Republic of); Jin, Wook [East-West Neo Medical Center, Seoul (Korea, Republic of)

    2007-02-15

    We wanted to evaluate the diagnostic value of the various findings on sacroiliac CT for detecting the early changes of ankylosing spondylitis (AS). Between April 2005 and March 2006, 51 sacroiliac CT images with the clinical suspicion of AS, but no definite evidence of AS on the plain radiograph only, were retrospectively reviewed. Finally, 36 patients (mean age: 28.6 years; 34 males and 2 females), who were clinically diagnosed as AS (AS group, n = 26) or they had no evidence of AS (non-AS group, n = 10), were evaluated. Two musculoskeletal radiologists analyzed the presence of marginal irregularity, bony erosion and subchondral sclerosis. A statistical analysis was performed to evaluate the incidence, sensitivity and specificity of each finding. Marginal irregularity was seen in 21 of 26 AS subjects, and in 8 of 10 non-AS subjects. Bony erosion was only seen in 13 of 26 AS subjects. Subchondral sclerosis was observed in 19 of 26 AS subjects and in 8 of 10 non-AS subjects. The sensitivity/specificity for each findings were 72.4%/28.6%, 100%/43.5% and 70.4%/22.2%, respectively. Except for bony erosions, these results showed no statistical significance ({rho} = .006). Bony erosion on CT is a very sensitive finding for the early changes of AS, whereas marginal irregularity or subchondral sclerosis is not so helpful in differentiating AS from non-AS. Attention to these results may further enhance the accurate diagnosis of the early changes in AS.

  13. Assessment of myocardial bridge by cardiac CT: Intracoronary transluminal attenuation gradient derived from diastolic phase predicts systolic compression

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Meng Meng; Zhang, Yang; Li, Yue Hua; Li, Wen Bin; Li, Ming Hua; Zhang, Jiayin [Institute of Diagnostic and Interventional Radiology, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, Shangha (China)

    2017-08-01

    To study the predictive value of transluminal attenuation gradient (TAG) derived from diastolic phase of coronary computed tomography angiography (CCTA) for identifying systolic compression of myocardial bridge (MB). Consecutive patients diagnosed with MB based on CCTA findings and without obstructive coronary artery disease were retrospectively enrolled. In total, 143 patients with 144 MBs were included in the study. Patients were classified into three groups: without systolic compression, with systolic compression < 50%, and with systolic compression ≥ 50%. TAG was defined as the linear regression coefficient between intraluminal attenuation in Hounsfield units (HU) and length from the vessel ostium. Other indices such as the length and depth of the MB were also recorded. TAG was the lowest in MB patients with systolic compression ≥ 50% (-19.9 ± 8.7 HU/10 mm). Receiver operating characteristic curve analysis was performed to determine the optimal cutoff values for identifying systolic compression ≥ 50%. The result indicated an optimal cutoff value of TAG as -18.8 HU/10 mm (area under curve = 0.778, p < 0.001), which yielded higher sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy (54.1, 80.5, 72.8, and 75.0%, respectively). In addition, the TAG of MB with diastolic compression was significantly lower than the TAG of MB without diastolic compression (-21.4 ± 4.8 HU/10 mm vs. -12.7 ± 8 HU/10 mm, p < 0.001). TAG was a better predictor of MB with systolic compression ≥ 50%, compared to the length or depth of the MB. The TAG of MB with persistent diastolic compression was significantly lower than the TAG without diastolic compression.

  14. The neck shaft angle: CT reference values of 800 adult hips

    Energy Technology Data Exchange (ETDEWEB)

    Boese, Christoph Kolja; Jostmeier, Janine; Oppermann, Johannes; Dargel, Jens; Eysel, Peer [University Hospital of Cologne, Department of Orthopaedic and Trauma Surgery, Cologne (Germany); Chang, De-Hua [University Hospital of Cologne, Department of Radiology and Neuroradiology, Cologne (Germany); Lechler, Philipp [University of Giessen and Marburg, Center of Orthopedic and Trauma Surgery, Marburg (Germany)

    2016-04-15

    A precise understanding of the radiological anatomy and biomechanics as well as reliable reference values of the hip are essential. The primary goal of this study was to provide reference values of the neck-shaft angle (NSA) for adult patients based on the analysis of rotation corrected computed tomography (CT) scans of 800 hips. The secondary aim was to compare these measurements with simulated anteroposterior roentgenograms of the pelvis. Pelvic CT scans of 400 patients (54.3 years, range 18-100 years; 200 female) were reconstructed in the derotated coronal plane of the proximal femur and as CT-based simulated anteroposterior roentgenograms of the pelvis in the anterior pelvic plane. Femora were categorized as coxa vara (<120 ), physiologic (≥120 to <135 ), and coxa valga (≥135 ). Intra- and inter-rater reliability were analyzed. Primary research question: Mean NSA for male adults was 129.6 (range 113.2 -148.2 ; SD 5.9 ) and 131.9 (range 107.1 -151.9 ; SD 6.8 ) for females in derotated coronal reconstructions. Age (p < 0.001 in both views) and sex influenced the NSA significantly (p = 0.002 and p < 0.001); no significant differences were found between sides (p = 0.722 and p = 0.955). Overall, an excellent reliability of repeated measurements of one or two observers was found (ICC 0.891-0.995). Secondary research question: NSA values measured in the simulated anteroposterior roentgenogram and the rotation corrected coronal reconstruction differed significantly (p < 0.001). While anteroposterior pelvis radiographs are susceptible to rotational errors, the coronal reconstruction of the proximal femur in the femoral neck plane allows the correct measurement of the NSA. (orig.)

  15. Small intestinal lipomas:Diagnostic value of multi-slice CT enterography

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To analyze the clinical and imaging features of the small intestinal lipomas and to evaluate the diagnostic value of multi-slice computed tomography(CT) enterography.METHODS:Fourteen cases(one had two intestinal lesions) of surgically confirmed lipomas of the small intestine were retrospectively analyzed.The location,size,clinical and radiological aspects were discussed.RESULTS:Twelve patients presented with abdominal pain,of whom three complained of paroxysmal colic.Melena or bloody stools was mentione...

  16. CT 与18 F-FDG PET/CT 影像在硬化性肺泡细胞瘤诊断中的价值%The Value of CT and 18 F-FDG PET/CT Imaging in the Dgnosis of Pulmonary Sclerosing Pneumocytoma

    Institute of Scientific and Technical Information of China (English)

    董有文; 徐文贵; 朱磊

    2016-01-01

    Objective To investigate the CT,contrast CT and 18 F-FDG PET/CT features of pulmonary sclerosing pneumocytoma(PSP),and improve the knowledge of imaging and metabolic characteristics of this tumor.Methods Clinical and imaging data of 135 patients with diagnosed PSP in our hospital from November 2008 to November 2015 were retrospectively reviewed.Results CT signs such as calcification,halo sign,air-crescent sign and lobulation sign accounted for 36.3%,37.9%,9.1% and 9.1%,respectively.Heterogeneous enhancement within the focal or punctate with low attenuation mostly occurred in enhanced CT scans(80.4%),and 82.6% accompanied by overlying vessel. 69.5% of the lesions showed intensive 18 F-FDG uptake,the tumor size and SUVmax was positively correlated(r=0.486, P =0.019),wherein typical PSP with significant correlation(r=0.769,P =0.001),atypical cases with no significant correlation(r=0.438,P =0.239).Seven patients have been carried out PET/CT and enhanced CT examination,among which six cases were significantly enhanced.Conclusion CT signs was helpful to PSP,however,it’s not specific.Con-trast CT is an effective diagnostic tool for the diagnosis of PSP.Diagnostic value of 18 F-FDG PET combined with en-hanced CT was relatively better than 18 F-FDG PET and 18 F-FDG PET/CT in pulmonary sclerosing pneumocytoma.%目的:探讨 CT、增强 CT 及18 F-FDG PET/CT 在硬化性肺泡细胞瘤(PSP)中的诊断价值。方法回顾分析2008年11月至2015年11月我院病理证实的135例 PSP 患者临床及影像资料。结果CT 显示钙化、晕征、空气新月征、分叶征在 PSP 中出现的几率分别为36.3%、37.9%、9.1%和9.1%;增强 CT 呈不均匀较高强化,增强后80.4%伴点状或灶状低密度影,82.6%有贴边血管征;69.5%的病灶显示明显18 F-FDG 摄取,病灶大小跟 SUVmax 呈正相关(r=0.486,P =0.019),其中典型 PSP 相关显著(r =0.769,P =0.001),不

  17. Contribution of the amount of contrast media used in pulmonary CT angiography to assess the diagnostic value of CT venography; comparison of 100 and 150 ml of contrast media

    Energy Technology Data Exchange (ETDEWEB)

    Calisir, C. [Department of Radiology, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir (Turkey)], E-mail: ccalisi1@jhmi.edu; Yavas, U.S.; Kebapci, M.; Korkmaz, A.; Ozkan, R. [Department of Radiology, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir (Turkey)

    2009-09-15

    Aim: To prospectively compare the vascular attenuation achieved with 100 ml iohexol (350 mg I/ml) 75% with that achieved with 150 ml iohexol (350 mg I/ml) 75% for computed tomography (CT) venography, which was performed after CT pulmonary angiography. Materials and methods: A total of 122 patients were included in the study. Group A, comprising 52 patients (mean age 64.8 years, mean body weight 70.8 kg) received 150 ml iohexol (350 mg I/ml) contrast media. Group B, comprising 70 patients (mean age 61.2 years, mean body weight 71.4 kg) received 100 ml iohexol (350 mg I/ml) contrast medium. Results: Venous opacification values measured at all levels were significantly higher in group A than those in group B (p < 0.001). In group B the mean HU values were between 87 and 115 and only three of the patients had HU values less than 60 at the level of femoral vein. Assuming a venous enhancement of 80 HU as the cut-off value for accurate diagnosis of deep venous thrombosis, 22.8% (16/70) in group B and 7.6% (4/52; p = 0.028) in group A had non-diagnostic CT venography of left femoral vein. Conclusion: One hundred millilitres of contrast medium with a concentration of 350 mg I/ml may produce sufficient enhancement, but 150 ml of contrast medium provides better accuracy for the diagnosis of deep venous thrombosis diagnosis. For better enhancement of lower extremity deep veins, the concentration of the contrast medium and the patient's body weight may also have significance.

  18. [The Difference of CT Value Related to Monitor Position in the Head CT-angiography Bolus Tracking Method for Patients with Subarachnoid Hemorrhage].

    Science.gov (United States)

    Mizui, Masato; Mizoguchi, Yuji; Tashiro, Takao

    2016-01-01

    The head computed tomography-angiography (head CT-A) examination is excellent for the detection and diagnosis of cerebral artery aneurysm. If we use bolus tracking method when implementing this examination, we must choose a monitoring point. We investigated the influence which the monitoring point (MCA or carotid-A) exerts on the CT value. As for the result, MCA monitoring point method was more excellent than the carotid artery monitoring point method. The CT value was higher about 50 HU in the MCA monitoring point than in the carotid artery monitoring point (average;carotid artery: 349.6±57.8 HU, MCA: 413.2±67.9 HU). So, we conclude that in the bolus tracking method of monitoring point of head CTA, MCA monitoring point should be used.

  19. Obesity and attenuated adiposity rebound in children with congenital hypothyroidism. Normalization of BMI values in adolescents.

    Science.gov (United States)

    Livadas, S; Magiakou, M-A; Mengreli, C; Girginoudis, P; Galani, C; Smyrnaki, P; Kanaka-Gantenbein, C; Xekouki, P; Chrousos, G P; Dacou-Voutetakis, C

    2007-07-01

    An earlier adiposity rebound, suggestive of adult obesity, has been reported in children with congenital hypothyroidism. We undertook this study to evaluate the effect of congenital hypothyroidism on: 1) the timing of adiposity rebound, 2) the long-term prognosis of BMI status, and 3) the factors potentially affecting adiposity in subjects with congenital hypothyroidism. We found that in children with congenital hypothyroidism the BMI values were higher during the first years of life compared to normal population, but subsequently normalized. After the initial rise of BMI, the decline (nadir) and subsequent rise (adiposity rebound), usually occurring in normal children at an age greater than 30 months, was less evident in our group of children with congenital hypothyroidism. The severity of hypothyroidism affected BMI values at 6 and 12, but not at 36 months of age. In conclusion, in children with congenital hypothyroidism, 1) the high BMI values in early childhood normalize in adolescence, and 2) the normally expected BMI fluctuations during the first years of life are attenuated. These findings constitute indirect evidence that thyroid function during fetal and neonatal life affects BMI status during the first years of life.

  20. Comparison of standardized uptake values measured on {sup 18}F-NaF PET/CT scans using three different tube current intensities

    Energy Technology Data Exchange (ETDEWEB)

    Valadares, Agnes Araujo; Woellner, Eduardo Bechtloff; Sapienza, Marcelo Tatit; Buchpiguel, Carlos Alberto, E-mail: agnesvaladares@me.com [Universidade de Sao Paulo (HC/FMUSP), Sao Paulo, SP (Brazil). Fac. de Medicina. Hospital das Clinicas; Duarte, Paulo Schiavom; Coura-Filho, George Barberio [Instituto do Cancer do Estado de Sao Paulo Octavio Frias de Oliveira (ICESP), Sao Paulo, SP (Brazil)

    2015-01-15

    Objective: to analyze standardized uptake values (SUVs) using three different tube current intensities for attenuation correction on {sup 18}FNaF PET/CT scans. Materials and methods: a total of 254 {sup 18}F-NaF PET/CT studies were analyzed using 10, 20 and 30 mAs. The SUVs were calculated in volumes of interest (VOIs) drawn on three skeletal regions, namely, right proximal humeral diaphysis (RH), right proximal femoral diaphysis (RF), and first lumbar vertebra (LV1) in a total of 712 VOIs. The analyses covered 675 regions classified as normal (236 RH, 232 RF, and 207 LV1). Results: mean SUV for each skeletal region was 3.8, 5.4 and 14.4 for RH, RF, and LV1, respectively. As the studies were grouped according to mAs value, the mean SUV values were 3.8, 3.9 and 3.7 for 10, 20 and 30 mAs, respectively, in the RH region; 5.4, 5.5 and 5.4 for 10, 20 and 30 mAs, respectively, in the RF region; 13.8, 14.9 and 14.5 for 10, 20 and 30 mAs, respectively, in the LV1 region. Conclusion: the three tube current values yielded similar results for SUV calculation. (author)

  1. Comparison of standardized uptake values measured on 18F-NaF PET/CT scans using three different tube current intensities

    Directory of Open Access Journals (Sweden)

    Agnes Araujo Valadares

    2015-02-01

    Full Text Available Objective: To analyze standardized uptake values (SUVs using three different tube current intensities for attenuation correction on 18FNaF PET/CT scans. Materials and Methods: A total of 254 18F-NaF PET/CT studies were analyzed using 10, 20 and 30 mAs. The SUVs were calculated in volumes of interest (VOIs drawn on three skeletal regions, namely, right proximal humeral diaphysis (RH, right proximal femoral diaphysis (RF, and first lumbar vertebra (LV1 in a total of 712 VOIs. The analyses covered 675 regions classified as normal (236 RH, 232 RF, and 207 LV1. Results: Mean SUV for each skeletal region was 3.8, 5.4 and 14.4 for RH, RF, and LV1, respectively. As the studies were grouped according to mAs value, the mean SUV values were 3.8, 3.9 and 3.7 for 10, 20 and 30 mAs, respectively, in the RH region; 5.4, 5.5 and 5.4 for 10, 20 and 30 mAs, respectively, in the RF region; 13.8, 14.9 and 14.5 for 10, 20 and 30 mAs, respectively, in the LV1 region. Conclusion: The three tube current values yielded similar results for SUV calculation.

  2. Emphysema quantification on low-dose CT using percentage of low-attenuation volume and size distribution of low-attenuation lung regions: Effects of adaptive iterative dose reduction using 3D processing

    Energy Technology Data Exchange (ETDEWEB)

    Nishio, Mizuho, E-mail: nmizuho@med.kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Matsumoto, Sumiaki, E-mail: sumatsu@med.kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Seki, Shinichiro, E-mail: sshin@med.kobe-u.ac.jp [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Koyama, Hisanobu, E-mail: hkoyama@med.kobe-u.ac.jp [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Fujisawa, Yasuko, E-mail: yasuko1.fujisawa@toshiba.co.jp [Toshiba Medical Systems Corporation, 1385 Shimoishigami, Otawara, Tochigi 324-8550 (Japan); Sugihara, Naoki, E-mail: naoki.sugihara@toshiba.co.jp [Toshiba Medical Systems Corporation, 1385 Shimoishigami, Otawara, Tochigi 324-8550 (Japan); and others

    2014-12-15

    Highlights: • Emphysema quantification (LAV% and D) was affected by image noise on low-dose CT. • For LAV% and D, AIDR 3D improved agreement of quantification on low-dose CT. • AIDR 3D has the potential to quantify emphysema accurately on low-dose CT. - Abstract: Purpose: To evaluate the effects of adaptive iterative dose reduction using 3D processing (AIDR 3D) for quantification of two measures of emphysema: percentage of low-attenuation volume (LAV%) and size distribution of low-attenuation lung regions. Method and materials: : Fifty-two patients who underwent standard-dose (SDCT) and low-dose CT (LDCT) were included. SDCT without AIDR 3D, LDCT without AIDR 3D, and LDCT with AIDR 3D were used for emphysema quantification. First, LAV% was computed at 10 thresholds from −990 to −900 HU. Next, at the same thresholds, linear regression on a log–log plot was used to compute the power law exponent (D) for the cumulative frequency-size distribution of low-attenuation lung regions. Bland–Altman analysis was used to assess whether AIDR 3D improved agreement between LDCT and SDCT for emphysema quantification of LAV% and D. Results: The mean relative differences in LAV% between LDCT without AIDR 3D and SDCT were 3.73%–88.18% and between LDCT with AIDR 3D and SDCT were −6.61% to 0.406%. The mean relative differences in D between LDCT without AIDR 3D and SDCT were 8.22%–19.11% and between LDCT with AIDR 3D and SDCT were 1.82%–4.79%. AIDR 3D improved agreement between LDCT and SDCT at thresholds from −930 to −990 HU for LAV% and at all thresholds for D. Conclusion: AIDR 3D improved the consistency between LDCT and SDCT for emphysema quantification of LAV% and D.

  3. Detection of occult vertebral fractures by quantitative assessment of bone marrow attenuation values at MDCT

    Energy Technology Data Exchange (ETDEWEB)

    Henes, Frank Oliver, E-mail: f.henes@uke.de [Department of Diagnostic and Interventional Radiology, Center for Radiology and Endoscopy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Groth, Michael [Department of Diagnostic and Interventional Neuroradiology, Center for Radiology and Endoscopy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Kramer, Harald [Department of Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistr. 15, 81377 Munich (Germany); Department of Radiology, University of Wisconsin – Madison, Clinical Science Center, 600 Highland Avenue, Madison, WI 53792 (United States); Schaefer, Christian [Department of Trauma-, Hand- and Reconstructive Surgery, Spine Center, Center for Surgical Sciences, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246 Hamburg (Germany); Regier, Marc; Derlin, Thorsten; Adam, Gerhard; Bannas, Peter [Department of Diagnostic and Interventional Radiology, Center for Radiology and Endoscopy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany)

    2014-01-15

    Objectives: To determine a cut-off value of Hounsfield attenuation units (HU) at multidetector computed tomography (MDCT) for valid and reliable detection of bone marrow oedema (BME) related to occult vertebral fractures. Methods: 36 patients underwent both MDCT and Magnetic Resonance Imaging (MRI) for evaluation of vertebral fractures of the thoracolumbar spine and were included in this retrospective study. Two readers independently assessed HU values at MDCT in a total of 196 vertebrae. Reliability was assessed by intraclass correlation coefficient and Bland–Altman analysis. For each patient we determined the vertebra with the lowest HU value and calculated the HU-difference to each other vertebral body. HU-differences were subjected to receiver operating characteristic (ROC) curve analysis to determine the diagnostic accuracy for detection of BME as determined by MRI, which served as the reference standard. Results of HU-measurements were compared with standard visual evaluation of MDCT. Results: HU measurements demonstrated a high interrater reliability (ICC = 0.984). ROC curve analysis (AUC = 0.978) exhibited an ideal cut-off value of 29.6 HU for detection of BME associated with vertebral fractures with an accuracy of 97.4% as compared to 93.4% accuracy of visual evaluation. Particularly, HU-measurements increased the sensitivity for detection of vertebral fractures from 78.0% to 92.7% due to the detection of 7 of 9 occult fractures that were missed by visual evaluation alone. Conclusions: Assessing bone marrow density by HU measurements using the cut-off of 29.6 HU is a valid and reliable tool for detection of BME related to occult vertebral fractures in MDCT. The introduced technique may allow more accurate treatment decisions and may make further diagnostic work-up with MRI unnecessary.

  4. Value of surveillance {sup 18}F FDG PET/CT in colorectal cancer:comparison with conventional imaging studies

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eun Kyoung; Yoo, Ie Ryung; Park, Hye Lim; Choi, Hyun Su; Han, Eun Ji; Kim, Sung Hoon; Chung, Soo Kyo; O, Joo Hyun [The Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2012-09-15

    To assess the value of PET/CT for detecting local or distant recurrence in patients who undergo surgery for colorectal cancer (CRC)and to compare the accuracy of PET/CT to that of conventional imaging studies (CIS). Tumor surveillance PET/CT scans done between March 2005 and December 2009 of disease free patients after surgery with or without adjuvant chemotherapy for CRC were retrospectively studied. CIS (serial enhanced CT from lung base to pelvis and plain chest radiograph)were performed within 1 month of PET/CT. We excluded patients with distant metastasis on initial staging, a known recurrent tumor, and a lack of follow up imaging. The final diagnosis was based on at least 6 months of follow up with colonoscopy, biopsy, and serial imaging studies in combination with carcinoembryonic antigen levels. A total of 262 PET/CT scans of 245 patients were included. Local and distant recurrences were detected in 27 cases (10.3%). On case based analysis, the overall sensitivity, specificity, and accuracy were 100, 97.0, and 97.3% for PET/CT and 85.1, 97.0, and 95.8% for CIS, respectively. On lesion based analysis, PET/CT detected more lesions compared to CIS in local recurrence and lung metastasis. PET/CT and CIS detected the same number of lesions in abdominal lymph nodes, hepatic metastasis, and peritoneal carcinomatosis. PET/CT detected two more metachronous tumors than did CIS in the lung and thyroid gland. PET/CT detected more recurrences in patients who underwent surgery for CRC than did CIS and had the additional advantage of evaluating the entire body during a single scan.

  5. The clinical features and diagnostic value of CT in Fahr’s disease

    Directory of Open Access Journals (Sweden)

    Wei-dong Hu

    2013-11-01

    Full Text Available Objectives:  To study the clinical features and diagnostic value of CT in Fahr’s disease. Methods:  We retrospectively analyzed skull images of 8,000 cases and observed the incidence and imaging characteristics of Fahr’s disease. Results: Fahr’s disease were found in 6 patients (6/4000=0.075%whose ages ranged from 16 to 62 years (average age:38.5±6.4years. We found that 6 Fahr’s disease had been incidentally detected in 4 men(4/6=66.7% and 2 women(2/6=33.4%; serum calcium:2.13~2.42 mmol/L,serum phosphor:1.0~1.6 mmol/L.The most common CT feature of Fahr’s disease is the presence of small bilateral intracranial calcifications which are usually restricted to the bilateral globus pallidus, putamen, caudate nucleus, thalamus, dentate nucleus and white matter of the cerebral hemispheres. Conclusions: Combined with clinical manifestations and imaging features, we can make a clear diagnosis of the Fahr’s disease.

  6. Commercial software upgrades may significantly alter Perfusion CT parameter values in colorectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Goh, Vicky [Mount Vernon Hospital, Paul Strickland Scanner Centre, Northwood, Middlesex (United Kingdom); Shastry, Manu; Endozo, Raymondo; Groves, Ashley M. [University College Hospital, Institute of Nuclear Medicine, London (United Kingdom); Engledow, Alec; Peck, Jacqui [University College Hospital, Department of Surgery, London (United Kingdom); Reston, Jonathan; Wellsted, David M. [University of Hertfordshire, Centre for Lifespan and Chronic Illness Research (CLiCIR), Hatfield (United Kingdom); Rodriguez-Justo, Manuel [University College Hospital, Department of Histopathology, London (United Kingdom); Taylor, Stuart A.; Halligan, Steve [University College Hospital, Specialist Radiology, London (United Kingdom)

    2011-04-15

    To determine how commercial software platform upgrades impact on derived parameters for colorectal cancer. Following ethical approval, 30 patients with suspected colorectal cancer underwent Perfusion CT using integrated 64 detector PET/CT before surgery. Analysis was performed using software based on modified distributed parameter analysis (Perfusion software version 4; Perfusion 4.0), then repeated using the previous version (Perfusion software version 3; Perfusion 3.0). Tumour blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) were determined for identical regions-of-interest. Slice-by-slice and 'whole tumour' variance was assessed by Bland-Altman analysis. Mean BF, BV and PS was 20.4%, 59.5%, and 106% higher, and MTT 14.3% shorter for Perfusion 4.0 than Perfusion 3.0. The mean difference (95% limits of agreement) were +13.5 (-44.9 to 72.0), +2.61 (-0.06 to 5.28), -1.23 (-6.83 to 4.36), and +14.2 (-4.43 to 32.8) for BF, BV, MTT and PS respectively. Within subject coefficient of variation was 36.6%, 38.0%, 27.4% and 60.6% for BF, BV, MTT and PS respectively indicating moderate to poor agreement. Software version upgrades of the same software platform may result in significantly different parameter values, requiring adjustments for cross-version comparison. (orig.)

  7. The diagnostic value of the sagittal multiplanar reconstruction CT images for nasal bone fractures

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B.H. [Department of Radiology, Korea University Ansan Hospital, 516 Gojan1-dong, Danwon-gu, Ansan-si, Gyunggi-do, 425-707 (Korea, Republic of); Seo, H.S., E-mail: seohs@korea.ac.k [Department of Radiology, Korea University Ansan Hospital, 516 Gojan1-dong, Danwon-gu, Ansan-si, Gyunggi-do, 425-707 (Korea, Republic of); Kim, A.-Y.; Lee, Y.S. [Department of Radiology, Dongguk University International Hospital, Gyunggi-do (Korea, Republic of); Lee, Y.H. [Department of Radiology, Korea University Ansan Hospital, 516 Gojan1-dong, Danwon-gu, Ansan-si, Gyunggi-do, 425-707 (Korea, Republic of); Suh, S.-I. [Department of Diagnostic Radiology, Korea University Guro Hospital, Seoul (Korea, Republic of); Lee, D.H. [Department of Radiology, Seoul Medical Center, Seoul (Korea, Republic of)

    2010-04-15

    Aim: To compare the diagnostic performance of sagittal multiplanar reconstruction (MPR) images and axial images for the detection of a nasal bone fracture. Materials and methods: This prospective study included 533 consecutive patients who underwent three-dimensional images with 64-section multidetector-row CT for the evaluation of a facial bone fracture between June 2007 and May 2008 (366 males; 167 females; mean age +- standard deviation 31.1 +- 21.2 years; age range 1-92 years). Two observers independently scored the possibility of a nasal bone fracture on axial and sagittal images. Receiver operating characteristic (ROC) curve analysis was performed. Results: The Az values of the sagittal images were higher than those of the axial images for both observers (p = 0.002 and 0.010, respectively) with higher accuracy (p < 0.001 and 0.016, respectively). The sensitivities of sagittal images were superior to those of axial images, especially for type 1 simple nasal bone fractures with no or minimal displacement (observer 1, 98.6 versus 72.8%; observer 2, 84.9 versus 71%). Conclusion: Sagittal MPR facial bone CT images provided superior diagnostic performance, and their addition to axial images is useful for the evaluation of nasal bone fractures.

  8. The value of Weight-Bearing CT scan in the evaluation of subtalar distraction bone block arthrodesis: Case report.

    Science.gov (United States)

    Welck, M J; Myerson, M S

    2015-12-01

    Subtalar distraction arthrodesis is performed in certain situations where there is loss of subtalar height, reduced talar declination and evidence of anterior tibiotalar impingement. Standard evaluation includes the assessment of the lateral talocalcaneal angle, calcaneal pitch, talocalcaneal height and talar declination angle on a weight bearing lateral radiograph. We present a case of erosive valgus subtalar osteoarthritis with subtalar collapse managed with a subtalar distraction arthrodesis. A weight bearing CT (WB-CT) scan was used in the assessment. The value of WB-CT for this indication is discussed, along with a discussion on surgical technique, complications and future directions. Copyright © 2015 European Foot and Ankle Society. All rights reserved.

  9. Value of {sup 18}F-FDG PET/CT in the detection of ovarian malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Park, Tae Gyu; Lee, Si Nae; Park, So Yeon [Dept. of Nuclear Medicine, Korea University Guro Hospital, Seoul (Korea, Republic of); and others

    2015-03-15

    Ovarian cancer is a leading cause of gynecologic malignancy. As symptoms of ovarian cancer are nonspecific, only 20 % of ovarian cancers are diagnosed while they are still limited to the ovaries. Thus, early and accurate detection of disease is important for an improved prognosis. For the accurate and effective diagnosis of ovarian malignancy on {sup 18}F-fluorodeoxyglucose ({sup 18}F--FDG) positron emission tomography/computed tomography (PET/CT), we analyzed several parameters, including visual assessment. A total of 51 peritoneal lesions in 19 patients who showed ovarian masses with diffuse peritoneal infiltration were enrolled. Twelve patients were confirmed to have ovarian malignancy and seven patients with benign disease by pathologic examination. All patients were examined by {sup 18}F--FDG PET/CT, and an additional 2-h delayed {sup 18}F--FDG PET/CT was also performed for 15 patients with 42 peritoneal lesions. We measured semiquantitative parameters including maximum and mean standardized uptake values (SUV{sub max}, SUV{sub mean}), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) on a 1-h initial {sup 18}F--FDG PET/CT image (Parameter1) and on a 2-h delayed image (Parameter2). Additionally, retention indices of each parameter were calculated, and each parameter among the malignant and benign lesions was compared by Mann-Whitney U test. We also assessed the visual characteristics of each peritoneal lesion, including metabolic extent, intensity, shape, heterogeneity, and total visual score. Associations between visual grades and malignancy were analyzed using linear by linear association methods. Moreover, a receiver operating characteristic (ROC) curve was analyzed to compare the effectiveness of significant parameters. In a comparison between the malignant and benign groups in the analysis of 51 total peritoneal lesions, SUV{sub max1}, SUV{sub mean1}, and TLG1 showed significant differences. Also, in the analysis of 42 peritoneal lesions

  10. 双源 CT 双能量虚拟平扫对脂肪肝的诊断价值%The diagnostic value of dual energy virtual non-contrast images in hepatic steatosis with dual source CT scanner

    Institute of Scientific and Technical Information of China (English)

    王士阗; 王萱; 王禨; 徐凯; 薛华丹; 金征宇

    2014-01-01

    dual energy images in portal venous phase:100kV and 140kV.The CT value and noise were measured in both left and right lobe of liver,spleen and inferior ve-na cava (IVC)and these data were compared between VNC group and true non-contrast (TNC,120kV)group.The rela-tionship between the noise in right lobe of liver and the diameter parameters,anteroposterior,left-right and mean diameter of upper abdomen was explored in both TNC and VNC groups.Two proposed criteria for diagnosis of moderate and severe he-patic steatosis were studied independently and compared at the same ROI:a,liver-spleen attenuation ratio of less than 0.8, and b,liver-IVC ratio of less than 1.0.Results:The mean CT value of liver (both left lobe and right lobe)and spleen on VNC images were higher than that in TNC images with statistical significance (P<0.01)with absolute difference less than 10HU.Noise was found lower at every ROI on VNC images than that on TNC images (P<0.01).The noise of right lobe of liver on TNC images had moderate correlation (r=0.562 to 0.608,P<0.01)with the diameter parameters,while on VNC images this correlation was less.It would be a better consistency with a kappa value of 0.591 when setting the liver-spleen attenuation ratio below 0.8 as diagnostic criteria of severe hepatic steatosis.When setting liver-IVC ratio below 1.0 as diag-nostic criteria,the kappa value was 0.458.Additionally,we found the average radiation dose with VNC images as a replace-ment of TNC acquisition was 24.2% less.Conclusion:VNC and TNC images have moderate consistency in diagnosis of in-termediate to severe hepatic steatosis,and a liver-spleen ratio of less than 0.8 is recommended as the diagnostic criteria.

  11. Attenuation and image quality in the use of protective bismuth in chest CT scans; Atenuacion y calidad de imagen en el empleo de protectores de bismuto en exploraciones de TC de torax

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Ruiz-Zorrila, J.; Fernandez Leton, P.; Martinez Gomez, L. C.; Casa de Julian, M. A. de la; Gilarranz Moreno, R.; Zucca Aparicio, D.; Minambres Moro, A.; Perez Moreno, J. M.

    2011-07-01

    For chest CT scans are protective of bismuth (Bi) with the aim of reducing the dose in the breast. The aim of this study was to evaluate the attenuation with thermoluminescent dosimeters in the glandular dose average when using these protective breast CT scans and to evaluate the image quality with and without protective Bismuth.

  12. Value of abdominal CT in patients of the surgical intensive care unit; Stellenwert der abdominellen CT bei chirurgischen Intensivpatienten

    Energy Technology Data Exchange (ETDEWEB)

    Rieger, J. [Abt. fuer Radiologie, Klinikum Innenstadt, Ludwig-Maximilians-Universitaet, Muenchen (Germany); Kerner, T. [Abt. fuer Chirurgie, Klinikum Innenstadt, Ludwig-Maximilians-Universitaet, Muenchen (Germany); Waydhas, C. [Abt. fuer Chirurgie, Klinikum Innenstadt, Ludwig-Maximilians-Universitaet, Muenchen (Germany); Schenk, F. [Abt. fuer Radiologie, Klinikum Innenstadt, Ludwig-Maximilians-Universitaet, Muenchen (Germany); Pfeifer, K.J. [Abt. fuer Radiologie, Klinikum Innenstadt, Ludwig-Maximilians-Universitaet, Muenchen (Germany)

    1996-09-01

    The purpose of the retrospective study reported was to examine the indications, findings and therapeutic consequences of 88 consecutive CT examinations of the abdomen of 62 patients of a surgical intensive care unit. The CT examinations were performed within 12 hours following indication. The most frequent indications were sepsis with suspected intra-abdominal foci (72.7%), suspected lesion of intra-abdominal organs due to a serious accident (13.6%), and acutely necrotising pancreatitis (11.4%). Clinically relevant findings were obtained in 71.6% of the patients, in 43.2% the decision was for invasive treatment (of 38 patients, 28 treated by surgery, and 10 by other interventional measures) within 48 hours, which meant an essential modification of hitherto planned treatment. Patients with a high MOF score (>5) exhibited a significantly higher rate of pathologic findings than patients with a low MOF score (0-2). In the cases of suspected organ lesions, CT did not add any further information. (orig./MG)

  13. Added value of CT perfusion compared to CT angiography in predicting clinical outcomes of stroke patients treated with mechanical thrombectomy

    Energy Technology Data Exchange (ETDEWEB)

    Tsogkas, Ioannis; Knauth, Michael; Schregel, Katharina; Behme, Daniel; Psychogios, Marios Nikos [University Medicine Goettingen, Department of Neuroradiology, Goettingen (Germany); Wasser, Katrin; Maier, Ilko; Liman, Jan [University Medicine Goettingen, Department of Neurology, Goettingen (Germany)

    2016-11-15

    CTP images analyzed with the Alberta stroke program early CT scale (ASPECTS) have been shown to be optimal predictors of clinical outcome. In this study we compared two biomarkers, the cerebral blood volume (CBV)-ASPECTS and the CTA-ASPECTS as predictors of clinical outcome after thrombectomy. Stroke patients with thrombosis of the M1 segment of the middle cerebral artery were included in our study. All patients underwent initial multimodal CT with CTP and CTA on a modern CT scanner. Treatment consisted of full dose intravenous tissue plasminogen activator, when applicable, and mechanical thrombectomy. Three neuroradiologists separately scored CTP and CTA images with the ASPECTS score. Sixty-five patients were included. Median baseline CBV-ASPECTS and CTA-ASPECTS for patients with favourable clinical outcome at follow-up were 8 [interquartile range (IQR) 8-9 and 7-9 respectively]. Patients with poor clinical outcome showed a median baseline CBV-ASPECTS of 6 (IQR 5-8, P < 0.0001) and a median baseline CTA-ASPECTS of 7 (IQR 7-8, P = 0.18). Using CBV-ASPECTS and CTA-ASPECTS raters predicted futile reperfusions in 96 % and 56 % of the cases, respectively. CBV-ASPECTS is a significant predictor of clinical outcome in patients with acute ischemic stroke treated with mechanical thrombectomy. (orig.)

  14. Prognostic Value of Quantitative Metabolic Metrics on Baseline Pre-Sunitinib FDG PET/CT in Advanced Renal Cell Carcinoma.

    Directory of Open Access Journals (Sweden)

    Ryogo Minamimoto

    Full Text Available The objective of this study was to prospectively evaluate various quantitative metrics on FDG PET/CT for monitoring sunitinib therapy and predicting prognosis in patients with metastatic renal cell cancer (mRCC.Seventeen patients (mean age: 59.0 ± 11.6 prospectively underwent a baseline FDG PET/CT and interim PET/CT after 2 cycles (12 weeks of sunitinib therapy. We measured the highest maximum standardized uptake value (SUVmax of all identified lesions (highest SUVmax, sum of SUVmax with maximum six lesions (sum of SUVmax, total lesion glycolysis (TLG and metabolic tumor volume (MTV from baseline PET/CT and interim PET/CT, and the % decrease in highest SUVmax of lesion (%Δ highest SUVmax, the % decrease in sum of SUVmax, the % decrease in TLG (%ΔTLG and the % decrease in MTV (%ΔMTV between baseline and interim PET/CT, and the imaging results were validated by clinical follow-up at 12 months after completion of therapy for progression free survival (PFS.At 12 month follow-up, 6/17 (35.3% patients achieved PFS, while 11/17 (64.7% patients were deemed to have progression of disease or recurrence within the previous 12 months. At baseline, PET/CT demonstrated metabolically active cancer in all cases. Using baseline PET/CT alone, all of the quantitative imaging metrics were predictive of PFS. Using interim PET/CT, the %Δ highest SUVmax, %Δ sum of SUVmax, and %ΔTLG were also predictive of PFS. Otherwise, interim PET/CT showed no significant difference between the two survival groups regardless of the quantitative metric utilized including MTV and TLG.Quantitative metabolic measurements on baseline PET/CT appears to be predictive of PFS at 12 months post-therapy in patients scheduled to undergo sunitinib therapy for mRCC. Change between baseline and interim PET/CT also appeared to have prognostic value but otherwise interim PET/CT after 12 weeks of sunitinib did not appear to be predictive of PFS.

  15. Sleep deprivation is associated with attenuated parametric valuation and control signals in the midbrain during value-based decision making.

    Science.gov (United States)

    Menz, Mareike M; Büchel, Christian; Peters, Jan

    2012-05-16

    Sleep deprivation (SD) has detrimental effects on cognition, but the affected psychological processes and underlying neural mechanisms are still essentially unclear. Here we combined functional magnetic resonance imaging and computational modeling to examine how SD alters neural representation of specific choice variables (subjective value and decision conflict) during reward-related decision making. Twenty-two human subjects underwent two functional neuroimaging sessions in counterbalanced order, once during rested wakefulness and once after 24 h of SD. Behaviorally, SD attenuated conflict-dependent slowing of response times, which was reflected in an attenuated conflict-induced decrease in drift rates in the drift diffusion model. Furthermore, SD increased overall choice stochasticity during risky choice. Model-based functional neuroimaging revealed attenuated parametric subjective value signals in the midbrain, parietal cortex, and ventromedial prefrontal cortex after SD. Conflict-related midbrain signals showed a similar downregulation. Findings are discussed with respect to changes in dopaminergic signaling associated with the sleep-deprived state.

  16. The clinical features and diagnostic value of CT in Fahr’s disease

    OpenAIRE

    Wei-dong Hu; Li Xiang; Xiu-rong Wang

    2013-01-01

    Objectives:  To study the clinical features and diagnostic value of CT in Fahr’s disease. Methods:  We retrospectively analyzed skull images of 8,000 cases and observed the incidence and imaging characteristics of Fahr’s disease. Results: Fahr’s disease were found in 6 patients (6/4000=0.075%)whose ages ranged from 16 to 62 years (average age:38.5±6.4years). We found that 6 Fahr’s disease had been incidentally detected in 4 men(4/6=66.7%) and 2 women(2/6=33.4%); serum calcium:2.13~2.42 mmol/L...

  17. Comparison of two different segmentation methods on planar lung perfusion scan with reference to quantitative value on SPECT/CT

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Min Seok; Kang, Yeon Koo; Ha, Seung Gyun [Dept. of Nuclear Medicine, Seoul National University Hospital, Seoul (Korea, Republic of); and others

    2017-06-15

    Until now, there was no single standardized regional segmentation method of planar lung perfusion scan. We compared planar scan based two segmentation methods, which are frequently used in the Society of Nuclear Medicine, with reference to the lung perfusion single photon emission computed tomography (SPECT)/computed tomography (CT) derived values in lung cancer patients. Fifty-five lung cancer patients (male:female, 37:18; age, 67.8 ± 10.7 years) were evaluated. The patients underwent planar scan and SPECT/CT after injection of technetium-99 m macroaggregated albumin (Tc-99 m-MAA). The % uptake and predicted postoperative percentage forced expiratory volume in 1 s (ppoFEV1%) derived from both posterior oblique (PO) and anterior posterior (AP) methods were compared with SPECT/CT derived parameters. Concordance analysis, paired comparison, reproducibility analysis and spearman correlation analysis were conducted. The % uptake derived from PO method showed higher concordance with SPECT/CT derived % uptake in every lobe compared to AP method. Both methods showed significantly different lobar distribution of % uptake compared to SPECT/CT. For the target region, ppoFEV1% measured from PO method showed higher concordance with SPECT/CT, but lower reproducibility compared to AP method. Preliminary data revealed that every method significantly correlated with actual postoperative FEV1%, with SPECT/CT showing the best correlation. The PO method derived values showed better concordance with SPECT/CT compared to the AP method. Both PO and AP methods showed significantly different lobar distribution compared to SPECT/CT. In clinical practice such difference according to different methods and lobes should be considered for more accurate postoperative lung function prediction.

  18. PET/CT surveillance in patients with Hodgkin lymphoma in first remission is associated with low positive predictive value and high costs

    DEFF Research Database (Denmark)

    El-Galaly, Tarec; Mylam, Karen Juul; Brown, Peter De Nully

    2012-01-01

    recurrence, a routine PET/CT was the primary tool for the diagnosis of relapse. Extranodal disease, interim PET positive lesions and PET activity at response evaluation were all associated with a PET/CT diagnosed preclinical relapse. The true positive rates of routine PET/CT vs. clinically indicated PET....../CT were 5 and 13%, respectively (p=0.02). The overall positive predictive value and negative predictive value of PET/CT was 28% and 100%, respectively. The estimated cost per routine PET/CT diagnosed relapse was 50.778 USD. Conclusions. A negative PET/CT reliably rules out a relapse. The high false...... positive rate, however, is an important limitation and a confirmatory biopsy is mandatory for the diagnosis of a relapse. With no proven survival benefit for patients with a pre-clinically diagnosed relapse, the high costs and low positive predictive value make PET/CT unfit for routine surveillance...

  19. Clinical value of {sup 11}C-methionine PET/CT in patients with plasma cell malignancy: comparison with {sup 18}F-FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Nakamoto, Yuji; Kurihara, Kensuke; Nakatani, Koya; Togashi, Kaori [Kyoto University Graduate School of Medicine, Department of Diagnostic Imaging and Nuclear Medicine, Kyoto (Japan); Nishizawa, Masatoshi; Yamashita, Kouhei; Kondo, Tadakazu; Takaori-Kondo, Akifumi [Kyoto University Graduate School of Medicine, Department of Hematology and Oncology, Kyoto (Japan)

    2013-05-15

    PET/CT using FDG has been widely used for the imaging of various malignant tumours, including plasma cell malignancy (PCM), but {sup 11}C-methionine (MET), as a radiolabelled amino acid tracer, may also be useful because PCM is able to activate protein synthesis. The purpose of this study was to evaluate the clinical value of PET/CT imaging using MET in PCM, including multiple myeloma, compared with that of FDG PET/CT. The study group comprised 20 patients with histologically proven PCM who underwent FDG PET/CT and MET PET/CT scans before (n = 6) or after (n = 14) treatment. Semiquantitative analysis was performed on a lesion basis. We also visually evaluated the scans qualitatively using a five-point scale (0, negative; 1, probably negative; 2, equivocal; 3, probably positive; 4, positive) on a lesion and a patient basis. The results were compared between the two scans. Active PCM was confirmed in 15 patients, including two patients with extramedullary lesions. Uptake of MET tended to be higher (maximum standardized uptake value 10.3 {+-} 5.6, mean {+-} SD) than that of FDG (3.4 {+-} 2.7, p < 0.001), and more lesions of grade 3 or 4 were depicted by MET (MET 156 lesions vs. FDG 58 lesions). On a patient basis, two patients were accurately diagnosed only by MET. In the remaining 18 patients, consistent results were obtained, but potential upgrade of staging or restaging was necessary in 6 of 11 positive patients because more abnormal lesions were demonstrated by MET. The patient-based sensitivity, specificity and accuracy of MET for restaging were 89 %, 100 % and 93 %, respectively, while those of FDG were 78 %, 100 % and 86 %, respectively. MET revealed an equal or greater number of lesions in PCM than FDG. MET may be especially useful when negative or inconclusive findings are obtained by FDG despite highly suspicious indications of recurrence. (orig.)

  20. Prognostic value of semiquantification NP-59 SPECT/CT in primary aldosteronism patients after adrenalectomy

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ching-Chu; Cheng, Mei-Fang; Tzen, Kai-Yuan; Yen, Ruoh-Fang [National Taiwan University Hospital and National Taiwan University College of Medicine, Department of Nuclear Medicine, Taipei (China); Wu, Vin-Cent; Wu, Kwan-Dun [National Taiwan University Hospital and National Taiwan University College of Medicine, Department of Internal Medicine, Taipei (China); Liu, Kao-Lang [National Taiwan University Hospital and National Taiwan University College of Medicine, Department of Medical Imaging, Taipei (China); Lin, Wei-Chou [National Taiwan University Hospital and National Taiwan University College of Medicine, Department of Pathology, Taipei (China); Collaboration: the TAIPAI Study Group

    2014-07-15

    Primary aldosteronism (PA), characterized by an excessive production of aldosterone, affects 5-13 % of patients with hypertension. Accurate strategies are needed for the timely diagnosis of PA to allow curability and prevention of excessive cardiovascular events and related damage. This study aimed to evaluate the usefulness of semiquantification of {sup 131}I-6β-iodomethyl-norcholesterol (NP-59) single photon emission computed tomography (SPECT)/CT in differentiating aldosterone-producing adenoma (APA) from idiopathic adrenal hyperplasia (IAH) and in predicting clinical outcomes after adrenalectomy. We retrospectively reviewed 49 PA patients who had undergone adrenalectomy after NP-59 SPECT/CT within 1 year. A conventional visual scale (VS) and two semiquantitative parameters generated from SPECT/CT, adrenal to liver ratio (ALR) and lesion to contralateral ratio of bilateral adrenal glands (CON), with cutoff values calculated by receiver-operating characteristic (ROC) analysis, were compared with pathology results and postsurgical outcomes to determine the accuracy. An ALR cutoff of 1.84 and a CON cutoff of 1.15 showed an ability to distinguish adenoma from hyperplasia similar to VS (p = 0.2592 and 0.1908, respectively). An ALR cutoff of 2.28 and a CON cutoff of 1.11 yielded the highest sensitivity and specificity to predict postsurgical outcomes, and an ALR of 2.28 had an ability superior to VS (p = 0.0215), while a CON of 1.11 did not (p = 0.1015). Patients with either ALR or CON greater than the cutoff had a high probability of positive postsurgical outcomes (n = 36/38), while patients with both ALR and CON less than the cutoff had a low probability of positive postsurgical outcomes (n = 2/11). Semiquantification of NP-59 scintigraphy has an ability similar to VS in differentiating APA from IAH, but an excellent ability to predict postsurgical outcomes of adrenalectomy. An ALR or CON greater than the cutoff strongly suggests benefits from adrenalectomy, and

  1. The value of {sup 18}F-DOPA PET-CT in patients with medullary thyroid carcinoma: comparison with {sup 18}F-FDG PET-CT

    Energy Technology Data Exchange (ETDEWEB)

    Beheshti, Mohsen; Poecher, Sigrid; Vali, Reza; Nader, Michael; Langsteger, Werner [St Vincent' s Hospital, Department of Nuclear Medicine and Endocrinology, PET-CT Center LINZ, Linz (Austria); Waldenberger, Peter [St Vincent' s Hospital, Department of Radiology, Linz (Austria); Broinger, Gabriele [St Vincent' s Hospital, Department of Clinical Pathology, Linz (Austria); Kohlfuerst, Susanne [General Hospital, Department of Nuclear Medicine and Special Endocrinology, Klagenfurt (Austria); Pirich, Christian [Medical University of Salzburg, Department of Nuclear Medicine, Salzburg (Austria); Dralle, Henning [University of Halle, Department of General, Visceral and Vascular Surgery, Halle (Germany)

    2009-06-15

    The purpose of this prospective study was to compare the value of DOPA PET-CT with FDG PET-CT in the detection of malignant lesions in patients with medullary thyroid carcinoma (MTC). Twenty-six consecutive patients (10 men, 16 women, mean age 59 {+-} 14 years) with elevated calcitonin levels were evaluated in this prospective study. DOPA and FDG PET-CT modalities were performed within a maximum of 4 weeks (median 7 days) in all patients. The data were evaluated on a patient- and lesion-based analysis. The final diagnosis of positive PET lesions was based on histopathological findings and/or imaging follow-up studies (i.e., DOPA and/or FDG PET-CT) for at least 6 months (range 6-24 months). In 21 (21/26) patients at least one malignant lesion was detected by DOPA PET, while only 15 (15/26) patients showed abnormal FDG uptake. DOPA PET provided important additional information in the follow-up assessment in seven (27%) patients which changed the therapeutic management. The patient-based analysis of our data demonstrated a sensitivity of 81% for DOPA PET versus 58% for FDG PET, respectively. In four (4/26) postoperative patients DOPA and FDG PET-CT studies were negative in spite of elevated serum calcitonin and CEA levels as well as abnormal pentagastrin tests. Overall 59 pathological lesions with abnormal tracer uptake were seen on DOPA and/or FDG PET studies. In the final diagnosis 53 lesions proved to be malignant. DOPA PET correctly detected 94% (50/53) of malignant lesions, whereas only 62% (33/53) of malignant lesions were detected with FDG PET. DOPA PET-CT showed superior results to FDG PET-CT in the preoperative and follow-up assessment of MTC patients. Therefore, we recommend DOPA PET-CT as a one-stop diagnostic procedure to provide both functional and morphological data in order to select those patients who may benefit from (re-)operation with curative intent as well as guiding further surgical procedures. (orig.)

  2. Optimizing CT for the evaluation of vestibular aqueduct enlargement:Inter-rater reproducibility and predictive value of reformatted CT measurements

    Institute of Scientific and Technical Information of China (English)

    Misun Hwang; Ryan Marovich; Samuel S. Shin; David Chi; Barton F. Branstetter IV

    2015-01-01

    Enlarged vestibular aqueduct (EVA), the most frequent identifiable cause of congenital hearing loss, is evaluated with high-definition multi-detector CT in the axial plane. Our purpose was to determine which reformatted CT measurements are most reproducible. Seven multiplanar reformatted images were created for each of the 64 temporal bones in patients with EVA. Intraclass correlation coefficients (ICC) were used to assess inter-observer variability, and both linear regression and ROC analyses were used to compare the measurements with severity of hearing loss, as assessed by pure tone audiometry. All seven measurements had excellent inter-observer variability, with average-measure ICC ranging from 0.92 to 0.98. There was no statistically significant correlation between the radiologic degree of aqueduct enlargement and severity of hearing loss using any of the seven measurements;ROC analyses revealed areas under the curves ranging from 0.57 to 0.73. Optimal accuracy was obtained with a threshold of 1.75 mm as measured at the aqueductal aperture in the P€oschl plane, with sensitivity of 0.75 and specificity of 0.63. Although the radiologic measurement may not serve as a reliable tool for assessing severity of EVA, P€oschl plane reformatting has proven to be better than conventional axial acquisition plane for identifying patients with clinically significant hearing loss.

  3. Diagnostic value of FDG-PET/(CT) in children with fever of unknown origin and unexplained fever during immune suppression.

    Science.gov (United States)

    Blokhuis, Gijsbert J; Bleeker-Rovers, Chantal P; Diender, Marije G; Oyen, Wim J G; Draaisma, Jos M Th; de Geus-Oei, Lioe-Fee

    2014-10-01

    Fever of unknown origin (FUO) and unexplained fever during immune suppression in children are challenging medical problems. The aim of this study is to investigate the diagnostic value of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and FDG-PET combined with computed tomography (FDG-PET/CT) in children with FUO and in children with unexplained fever during immune suppression. All FDG-PET/(CT) scans performed in the Radboud university medical center for the evaluation of FUO or unexplained fever during immune suppression in the last 10 years were reviewed. Results were compared with the final clinical diagnosis. FDG-PET/(CT) scans were performed in 31 children with FUO. A final diagnosis was established in 16 cases (52 %). Of the total number of scans, 32 % were clinically helpful. The sensitivity and specificity of FDG-PET/CT in these patients was 80 % and 78 %, respectively. FDG-PET/(CT) scans were performed in 12 children with unexplained fever during immune suppression. A final diagnosis was established in nine patients (75 %). Of the total number of these scans, 58 % were clinically helpful. The sensitivity and specificity of FDG-PET/CT in children with unexplained fever during immune suppression was 78 % and 67 %, respectively. FDG-PET/CT appears a valuable imaging technique in the evaluation of children with FUO and in the diagnostic process of children with unexplained fever during immune suppression. Prospective studies of FDG-PET/CT as part of a structured diagnostic protocol are warranted to assess the additional diagnostic value.

  4. Diagnostic value of FDG-PET/(CT) in children with fever of unknown origin and unexplained fever during immune suppression

    Energy Technology Data Exchange (ETDEWEB)

    Blokhuis, Gijsbert J.; Diender, Marije G.; Oyen, Wim J.G. [Radboud University Medical Center, Department of Nuclear Medicine, Nijmegen (Netherlands); Bleeker-Rovers, Chantal P. [Radboud University Medical Center, Division of Infectious Diseases, Department of Internal Medicine, Nijmegen (Netherlands); Draaisma, Jos M.T. [Radboud University Medical Center, Department of Paediatrics, Nijmegen (Netherlands); Geus-Oei, Lioe-Fee de [Radboud University Medical Center, Department of Nuclear Medicine, Nijmegen (Netherlands); University of Twente, MIRA Institute for Biomedical Technology and Technical Medicine, Biomedical Photonic Imaging Group, Enschede (Netherlands)

    2014-10-15

    Fever of unknown origin (FUO) and unexplained fever during immune suppression in children are challenging medical problems. The aim of this study is to investigate the diagnostic value of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and FDG-PET combined with computed tomography (FDG-PET/CT) in children with FUO and in children with unexplained fever during immune suppression. All FDG-PET/(CT) scans performed in the Radboud university medical center for the evaluation of FUO or unexplained fever during immune suppression in the last 10 years were reviewed. Results were compared with the final clinical diagnosis. FDG-PET/(CT) scans were performed in 31 children with FUO. A final diagnosis was established in 16 cases (52 %). Of the total number of scans, 32 % were clinically helpful. The sensitivity and specificity of FDG-PET/CT in these patients was 80 % and 78 %, respectively. FDG-PET/(CT) scans were performed in 12 children with unexplained fever during immune suppression. A final diagnosis was established in nine patients (75 %). Of the total number of these scans, 58 % were clinically helpful. The sensitivity and specificity of FDG-PET/CT in children with unexplained fever during immune suppression was 78 % and 67 %, respectively. FDG-PET/CT appears a valuable imaging technique in the evaluation of children with FUO and in the diagnostic process of children with unexplained fever during immune suppression. Prospective studies of FDG-PET/CT as part of a structured diagnostic protocol are warranted to assess the additional diagnostic value. (orig.)

  5. The influence of body mass index and gender on coronary arterial attenuation with fixed iodine load per body weight at dual-source CT coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiaomei; Zhu, Yinsu; Xu, Hai; Tang, Lijun; Xu, Yi [Dept. of Radiology, the First Affiliated Hospital of Nanjing Medical Univ., Nanjing, Jiangsu (China)], E-mail: lijun.tang@hotmail.com

    2012-07-15

    Background. Most of current coronary CT angiography protocols are not adapted to body weight (BW) or cardiac output and no literature about influence of gender on coronary attenuation are reported with administration of a fixed iodine load per BW. Purpose. To determine the influence of body mass index (BMI) and gender on coronary arterial attenuation if contrast material dose is linearly adjusted to a patient's BW at dual-source CT coronary angiography (DSCT-CA). Material and Methods. A total of 207 consecutive patients (mean age 60.6 years) undergoing DSCT-CA were included. Contrast material (370 mg I/mL) dose calculation was randomly categorized into two groups (Group1: 1.10 mL/kg for men and women; Group 2: men 1.10 mL/kg, women 0.99 mL/kg) and flow rate was calculated as dose was divided by scan time plus 8 s. Mean arterial attenuations between men and women were compared with respect to attenuations of ascending aorta (AA) above coronary ostia, left main coronary artery (LM), proximal segments of right coronary artery (RCA), left anterior descending (LAD), and left circumflex artery (LCX) in two groups, respectively. Attenuations of coronary arteries were correlated with BW and BMI with simple linear regression. Results. The mean attenuations of AA, LM, RCA, LAD, and LCX were 407.8 {+-} 53.6 HU, 412.6 {+-} 55.4 HU, 411.4 {+-} 64.3 HU, 399.1 {+-} 56.7 HU, and 399.1 {+-} 60.2 HU, respectively, and there were no significant differences between men and women in group 1 (AA, P = 0.571; LM, P = 0.670; RCA, P = 0.737; LAD, P = 0.439, and LCX, P = 0.888). In group 2, the mean attenuations of AA, LM, RCA, LAD, and LCX in men were significantly higher than those in women (AA, P = 0.008; LM, P = 0.025; RCA, P = 0.017; LAD, P = 0.015, and LCX, P = 0.002). Positive linear regression between BW and attenuations of AA (R{sup 2} = 0.047, P = 0.02), LM (R{sup 2} = 0.036, P = 0.04), RCA (R{sup 2} = 0.080, P < 0.01), LAD (R{sup 2} = 0.078, P < 0.01), and LCX (R{sup 2} = 0

  6. Value of PET/CT and MR Lymphography in Treatment of Prostate Cancer Patients With Lymph Node Metastases

    Energy Technology Data Exchange (ETDEWEB)

    Fortuin, Ansje S., E-mail: A.Fortuin@rad.umcn.nl [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Deserno, Willem M.L.L.G. [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Meijer, Hanneke J.M. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Jager, Gerrit J. [Department of Radiology, Jeroen Bosch Hospital' s, Hertogenbosch (Netherlands); Takahashi, Satoru; Debats, Oscar A. [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Reske, Sven N.; Schick, Christian [Department of Nuclear Medicine, University of Ulm, Ulm (Germany); Krause, Bernd J. [Department of Nuclear Medicine, Technische Universitaet Muenchen, Muenchen (Germany); Oort, Inge van; Witjes, Alfred J. [Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Hoogeveen, Yvonne L. [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Lin, Emile N.J.Th. van [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Barentsz, Jelle O. [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)

    2012-11-01

    Purpose: To determine the clinical value of two novel molecular imaging techniques: {sup 11}C-choline positron emission tomography (PET)/computed tomography (CT) and ferumoxtran-10 enhanced magnetic resonance imaging (magnetic resonance lymphography [MRL]) for lymph node (LN) treatment in prostate cancer (PCa) patients. Therefore, we evaluated the ability of PET/CT and MRL to assess the number, size, and location of LN metastases in patients with primary or recurrent PCa. Methods and Materials: A total of 29 patients underwent MRL and PET/CT for LN evaluation. The MRL and PET/CT data were analyzed independently. The number, size, and location of the LN metastases were determined. The location was described as within or outside the standard clinical target volume for elective pelvic irradiation as defined by the Radiation Therapy Oncology Group. Subsequently, the results from MRL and PET/CT were compared. Results: Of the 738 LNs visible on MRL, 151 were positive in 23 of 29 patients. Of the 132 LNs visible on PET/CT, 34 were positive in 13 of 29 patients. MRL detected significantly more positive LNs (p < 0.001) in more patients than PET/CT (p = 0.002). The mean diameter of the detected suspicious LNs on MRL was significantly smaller than those detected by PET/CT, 4.9 mm and 8.4 mm, respectively (p < 0.0001). In 14 (61%) of 23 patients, suspicious LNs were found outside the clinical target volume with MRL and in 4 (31%) of 13 patients with PET/CT. Conclusion: In patients with PCa, both molecular imaging techniques, MRL and {sup 11}C-choline PET/CT, can detect LNs suspicious for metastasis, irrespective of the existing size and shape criteria for CT and conventional magnetic resonance imaging. On MRL and PET/CT, 61% and 31% of the suspicious LNs were located outside the conventional clinical target volume. Therefore, these techniques could help to individualize treatment selection and enable image-guided radiotherapy for patients with PCa LN metastases.

  7. Assessment of Total Lesion Glycolysis by (18)F FDG PET/CT Significantly Improves Prognostic Value of GEP and ISS in Myeloma.

    Science.gov (United States)

    McDonald, James E; Kessler, Marcus M; Gardner, Michael W; Buros, Amy F; Ntambi, James A; Waheed, Sarah; van Rhee, Frits; Zangari, Maurizio; Heuck, Christoph J; Petty, Nathan; Schinke, Carolina; Thanendrarajan, Sharmilan; Mitchell, Alan; Hoering, Antje; Barlogie, Bart; Morgan, Gareth J; Davies, Faith E

    2017-04-15

    Purpose: Fluorine-18 fluorodeoxyglucose positron emission tomography with CT attenuation correction ((18)F-FDG PET/CT) is useful in the detection and enumeration of focal lesions and in semiquantitative characterization of metabolic activity (glycolytic phenotype) by calculation of glucose uptake. Total lesion glycolysis (TLG) and metabolic tumor volume (MTV) have the potential to improve the value of this approach and enhance the prognostic value of disease burden measures. This study aims to determine whether TLG and MTV are associated with progression-free survival (PFS) and overall survival (OS), and whether they improve risk assessments such as International Staging System (ISS) stage and GEP70 risk.Experimental Design: 192 patients underwent whole body PET/CT in the Total Therapy 3A (TT3A) trial and were evaluated using three-dimensional region-of-interest analysis with TLG, MTV, and standard measurement parameters derived for all focal lesions with peak SUV above the background red marrow signal.Results: In multivariate analysis, baseline TLG > 620 g and MTV > 210 cm(3) remained a significant factor of poor PFS and OS after adjusting for baseline myeloma variables. Combined with the GEP70 risk score, TLG > 205 g identifies a high-risk-behaving subgroup with poor expected survival. In addition, TLG > 205 g accurately divides ISS stage II patients into two subgroups with similar outcomes to ISS stage I and ISS stage III, respectively.Conclusions: TLG and MTV have significant survival implications at baseline and offer a more precise quantitation of the glycolytic phenotype of active disease. These measures can be assessed more readily than before using FDA-approved software and should be standardized and incorporated into clinical trials moving forward. Clin Cancer Res; 23(8); 1981-7. ©2016 AACR. ©2016 American Association for Cancer Research.

  8. CT evaluation of solitary pulmonary nodule : value of additional HRCT scan

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeung Sook; Kwak Jin Young; Lee, Seung Ik; Ha, Doo Hoe [Pundang CHA General Hospital, Pochon CHA Univ. College of Medicine, Sungnam (Korea, Republic of); Kim, Tae Sung; Hwang, Jung Hwa; Lee, Kyung Soo [Samsung Medical Center, Sungkyunkwan Univ. College of Medicine, Seoul (Korea, Republic of); Kim, Yook Yung [Ewha Womans Univ. College of Medicine, Seoul (Korea, Republic of)

    1999-04-01

    The aim of our study was to evaluate the usefulness of high-resolution CT scans in addition to helical CT for characterizing a solitary pulmonary nodule. Our study included 49 patients with a solitary pulmonary nodule ; in each patient this was evaluated by both additional high-resolution CT and helical scanning. Images were evaluated by three independent observers, each of whom read them twice : initially with helical CT images only and then with helical images plus high-resolution CT images. After analysis, the observers recorded the following : histologic diagnosis, benignancy or malignancy of a nodule, and confidence in their diagnosis (three scales). In differentiating benign and malignant nodules, the accuracy of helical scans only was 75% (110/147 readings) whereas that of helical plus high-resolution CT scans was 82% (121/147 readings)({rho}=0.001). Correct histologic diagnosis was made in 47% of cases (69/147 readings) when helical scans only had been evaluated and in 48% of cases (71/147 readings) for which both helical and high-resolotion CT scans were available ({rho}=0.815). Diagnosis was more often highly confident on the basis of additional high-resolution CT scans (25%) than helical scans only (5%) ({rho}=0.001). By enhancing differential diagnostic accuracy between benign and malignant nodules and by increasing confidence in the histologic diagnosis of a pulmonary nodule, additional high-resolution CT scans are valuable for the evaluation of a solitary pulmonary nodule.

  9. Diagnostic Value of CT for the Detection of Cervical Lymph Node Metastases in Papillary Thyroid Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Son, Kyu Ri [Boramae Medical Center, Seoul (Korea, Republic of); Na, Dong Gyu; Chang, Kee Hyun [Seoul National University Hospital, Seoul (Korea, Republic of)

    2009-06-15

    To determine the diagnostic accuracy of CT for the detection of cervical lymph node metastases in patients with papillary thyroid carcinoma (PTC). Two hundred twelve consecutive patients with surgically proven PTC were included in this study. CT images were retrospectively evaluated to determine the presence of a node metastasis using morphologic CT criteria (at least one of the following: strong nodal enhancement without hilar vessel enhancement, heterogeneous enhancement, calcification, and cystic change). The diagnostic accuracy of CT for the diagnosis of a metastatic lymph node was assessed using a level-bylevel analysis. The accuracy of the CT finding for strong nodal enhancement was greater than the other morphologic CT criteria (81.6% and 74.5-78.5%, respectively). The sensitivity, specificity, and accuracy were 64.4%, 91.4%, and 84.3% by the morphologic CT criteria, and were 34.6%, 93.9%, and 78.2% by size criteria, respectively. The morphologic CT criteria are more accurate than the size criteria in the detection of cervical lymph node metastases in patients with papillary thyroid carcinoma; and, strong nodal enhancement on a CT scan is the most important factor for its diagnostic accuracy.

  10. Diagnostic value of F18-FDG PET/CT in patients with the revised definition of fever of unknown origin

    DEFF Research Database (Denmark)

    Prakash, Vineet; Ketharanathan, Nagulabaskaran; Lorenz, Eleanor

    2009-01-01

    than 3 weeks duration and an uncertain diagnosis after comprehensive evaluation as an inpatient or outpatient for a minimum of 3 days or 3 outpatient visits, having excluded immunocompromised states. 59 patients (pts) (F=35, age 18-92) with this definition underwent PET with full diagnostic contrast......Objectives: Fever of unknown origin (FUO) is an increasingly accepted indication for PET/CT where it has a relatively high diagnostic yield. This study assesses its diagnostic value for the revised definition of FUO. Methods: The revised definition of FUO is fever of greater than 38.3C for more...... enhanced CT. The value of PET/CT in determining the underlying etiology of FUO was retrospectively evaluated by comparing the study findings with a final diagnosis. Final diagnosis was formulated by 6 month clinical, imaging, microbiological and histopathological follow up. When no cause was found...

  11. Detection of ingested cocaine-filled packets-Diagnostic value of unenhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Sabine [Department of Radiology, University Hospital-CHUV, Rue du Bugnon, 1011 Lausanne (Switzerland)], E-mail: sabine.schmidt@chuv.ch; Hugli, Olivier [Medical Emergency Department, University Hospital-CHUV, Rue du Bugnon, 1011 Lausanne (Switzerland); Rizzo, Elena; Lepori, Domenico; Gudinchet, F. [Department of Radiology, University Hospital-CHUV, Rue du Bugnon, 1011 Lausanne (Switzerland); Yersin, Bertrand [Medical Emergency Department, University Hospital-CHUV, Rue du Bugnon, 1011 Lausanne (Switzerland); Schnyder, Pierre; Meuwly, Jean-Yves [Department of Radiology, University Hospital-CHUV, Rue du Bugnon, 1011 Lausanne (Switzerland)

    2008-07-15

    Purpose: Emergency departments are facing nowadays an increasing number of illegal drug-related health problems, associated with medicolegal and/or social consequences. Body stuffers are street cocaine dealers, who either store wrapped packets of drugs in their rectum or hastily swallow them, prompted by fear of police's arrest. These packets can be life threatening in case of leakage. We evaluate the diagnostic value of unenhanced multidetector CT (MDCT) for detection of cocaine-filled packets (CFP) ingested by body stuffers in a phantom model. Materials and methods: Our phantom simulated normal bowel contents in which a varying number of true and false CFP were randomly mixed. Both only differ in radiological density. During 18 different reading sessions, four radiologists independently evaluated the presence and number of true and false CFP. Interobserver agreement, sensitivity, specificity, positive and negative predictive value were calculated. Results: Interobserver agreement for detection of any packets, for visualization of true, and false CFP was good ({kappa} = 0.63, 0.74 and 0.58, respectively). Sensitivity, specificity, positive and negative predictive value for detection of any packets was 95.6%, 100%, 100% and 62.5%, respectively; for visualization of the true CFP 86.5%, 100%, 100% and 77.6%, respectively; and for the false packets 98.1%, 65%, 88.6% and 87.5%, respectively. Conclusion: Unenhanced MDCT without bowel preparation is a fast, reliable and easily reproducible imaging modality for the immediate detection of ingested CFP, thus facilitating medicolegal management of body stuffers.

  12. FDG PET/CT and diffusion-weighted imaging for breast cancer: prognostic value of maximum standardized uptake values and apparent diffusion coefficient values of the primary lesion

    Energy Technology Data Exchange (ETDEWEB)

    Nakajo, Masatoyo [Nanpuh Hospital, Department of Radiology, Kagoshima (Japan); Kagoshima University, Department of Radiology, Graduate School of Medical and Dental Sciences, Kagoshima (Japan); Kajiya, Yoriko; Tani, Atsushi; Ueno, Masako [Nanpuh Hospital, Department of Radiology, Kagoshima (Japan); Kaneko, Tomoyo; Kaneko, Youichi [Kaneko Clinic, Department of Breast Surgery, Kagoshima (Japan); Takasaki, Takashi [Department of Pathology, Clinical Pathology Laboratory, Kagoshima (Japan); Koriyama, Chihaya [Kagoshima University, Department of Epidemiology and Preventive Medicine, Graduate School of Medical and Dental Sciences, Kagoshima (Japan); Nakajo, Masayuki [Kagoshima University, Department of Radiology, Graduate School of Medical and Dental Sciences, Kagoshima (Japan)

    2010-11-15

    To correlate both primary lesion {sup 18}F-fluorodeoxyglucose (FDG) maximum standardized uptake value (SUVmax) and diffusion-weighted imaging (DWI) apparent diffusion coefficient (ADC) with clinicopathological prognostic factors and compare the prognostic value of these indexes in breast cancer. The study population consisted of 44 patients with 44 breast cancers visible on both preoperative FDG PET/CT and DWI images. The breast cancers included 9 ductal carcinoma in situ (DCIS) and 35 invasive ductal carcinomas (IDC). The relationships between both SUVmax and ADC and clinicopathological prognostic factors were evaluated by univariate and multivariate regression analysis and the degree of correlation was determined by Spearman's rank test. The patients were divided into a better prognosis group (n = 24) and a worse prognosis group (n = 20) based upon invasiveness (DCIS or IDC) and upon their prognostic group (good, moderate or poor) determined from the modified Nottingham prognostic index. Their prognostic values were examined by receiver operating characteristic analysis. Both SUVmax and ADC were significantly associated (p<0.05) with histological grade (independently), nodal status and vascular invasion. Significant associations were also noted between SUVmax and tumour size (independently), oestrogen receptor status and human epidermal growth factor receptor-2 status, and between ADC and invasiveness. SUVmax and ADC were negatively correlated ({rho}=-0.486, p = 0.001) and positively and negatively associated with increasing of histological grade, respectively. The threshold values for predicting a worse prognosis were {>=}4.2 for SUVmax (with a sensitivity, specificity and accuracy of 80%, 75% and 77%, respectively) and {<=}0.98 for ADC (with a sensitivity, specificity and accuracy of 90%, 67% and 77%, respectively). SUVmax and ADC correlated with several of pathological prognostic factors and both indexes may have the same potential for predicting the

  13. CT scan of the hypopharynx and larynx. Value of phonation scans

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Naoko; Anno, Hirofumi; Takahashi, Masaki; Koga, Sukehiko; Mori, Shigeki; Iwata, Shigenobu; Ikuta, Katsumi; Mashita, Shinichi.

    1988-08-01

    29 patients with hypopharyngeal or laryngeal disorders were sustained phonation of vowel /E/ at their comfortable pitch and intensity levels on their CT scans. These images were compared with CT scans during quiet breathing or breath holding. The pyriform sinuses and the aryepiglottic folds were better visualized and the details of the glottis and the laryngeal ventricles were demonstrable during phonation.

  14. Chest wall infiltration by lung cancer: value of thin-sectional CT with different reconstruction algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Uhrmeister, P.; Allmann, K.H.; Altehoefer, C.; Laubenberger, J.; Langer, M. [Department of Diagnostic Radiology, University Hospital Freiburg (Germany); Wertzel, H.; Hasse, J. [Department of Thoracic Surgery, University Hospital Freiburg (Germany)

    1999-09-01

    The aim of this investigation was to evaluate whether thin-sectional CT with different reconstruction algorithms can improve the diagnostic accuracy with regard to chest wall invasion in patients with peripheral bronchogenic carcinoma. Forty-one patients with intrapulmonary lesions and tumor contact to the thoracic wall as seen on CT staging underwent additional 1-mm CT slices with reconstruction in a high-resolution (HR) and an edge blurring, soft detail (SD) algorithm. Five criteria were applied and validated by histological findings. Using the criteria of the intact fat layer, HRCT had a sensitivity of 81 % and a specificity of 79 %, SD CT had a sensitivity of 96 % and a specificity of 78 %, and standard CT technique had a sensitivity of 50 % and a specificity of 71 %, respectively. Regarding changes of intercostal soft tissue, HRCT achieved a sensitivity of 71 % and a specificity of 96 %, SD CT had a sensitivity of 94 % and a specificity of 96 % (standard CT technique: sensitivity 50 % and specificity 96 %). For the other criteria, such as pleural contact area, angle, and osseous destruction, no significant differences were found. Diagnostic accuracy of chest wall infiltration can be improved by using thin sectional CT. Especially the application of an edge-blurring (SD) algorithm increases sensitivity and specificity without additional costs. (orig.) With 4 figs., 1 tab., 26 refs.

  15. Non-Hodgkin lymphoma in skeletal muscle manifesting as homogeneous masses with CT attenuation similar to muscle

    Energy Technology Data Exchange (ETDEWEB)

    Panicek, D.M.; Lautin, J.L.; Schwartz, L.H.; Castellino, R.A. [Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021 (United States)

    1997-11-01

    Two cases are presented of masses in muscle due to non-Hodgkin lymphoma (NHL) that were homogeneous and isoattenuating to normal muscle on CT. In each case, the mass was clinically suspected of representing soft tissue sarcoma. However, the masses were relatively inapparent on CT, being visible predominantly as mass effect - an appearance unlike that of soft tissue sarcomas. It is important to be aware that NHL in muscle can be difficult to detect at CT, even with intravenous contrast enhancement; therefore, a clinically apparent mass should not be dismissed on the basis of an apparently unremarkable CT scan of the region. Such findings should suggest the diagnosis of NHL rather than sarcoma. (orig.) With 2 figs., 7 refs.

  16. The value of chest CT scan and tumor markers detection in sputum for early diagnosis of peripheral lung cancer

    Institute of Scientific and Technical Information of China (English)

    WANG Xu; CAO Aihong; PENG Mengqing; HU Chunfeng; LIU Delin; GU Tao; LIU Hui

    2004-01-01

    Objective To investigate the diagnostic value of chest CT scan combined with telomerase activity and p16 gene methylation from exfoliated cells of sputum in 55 cases of solitary pulmonary nodules (SPN; ≤30 mm)suspected early peripheral lung cancer. Methods The sputum specimens from 34 cases of cancer nodules and 21 cases of benign lesion were detected for telomerase activity by TRAP-PCR-ELISA and p16 gene methylation by PCR-based methylation analysis. Results The qualitative diagnostic accuracy of CT scan was 61.8%(34/55) for SPN provided by pathology. Cytology analysis of sputum was positive in 13 cases (38.2%). Telomerase activity was positive in 29 cases: sensitivity was 79.4%, specificity was 90.5%, accuracy was 83.6%; p16 gene methylation was found in 11 cases: sensitivity was 32.4%, specificity was 100.0%, and accuracy was 58.2%. The sensitivity was increased to 86.1% by combination of telomerase activity and p16 gene methylation. Compared with nodules without malignant CT signs, expression of telomerase activity and p16 methylation of SPN with malignant CT signs (lobulation or spiculate protuberance or spicule sign) had a significant difference (P<0.01). Conclusion The results suggest that chest CT scan combined with telomerase activity and p16 gene methylation detection in sputum for patients with peripheral lung cancer may enhance the diagnostic value of radiology and conventional cytology.

  17. The value of {sup 18}F-FDG PET/CT in the management of malignant peripheral nerve sheath tumors

    Energy Technology Data Exchange (ETDEWEB)

    Khiewvan, Benjapa [University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States); Mahidol University, Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine Siriraj Hospital, Bangkok (Thailand); Macapinlac, Homer A.; Chuang, Hubert H. [University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States); Lev, Dina; Al Sannaa, Ghadah [University of Texas MD Anderson Cancer Center, Department of Cancer Biology, Houston, TX (United States); McCutcheon, Ian E. [University of Texas MD Anderson Cancer Center, Department of Neurosurgery, Houston, TX (United States); Slopis, John M. [University of Texas MD Anderson Cancer Center, Department of Neuro-Oncology, Houston, TX (United States); Wei, Wei [University of Texas MD Anderson Cancer Center, Department of Biostatistics, Houston, TX (United States)

    2014-09-15

    Our objective was to determine how positron emission tomography (PET)/CT had been used in the clinical treatment of malignant peripheral nerve sheath tumor (MPNST) patients at The University of Texas MD Anderson Cancer Center. We reviewed a database of MPNST patients referred to MD Anderson Cancer Center during 1995-2011. We enrolled 47 patients who underwent PET/CT imaging. Disease stage was based on conventional imaging and PET/CT findings using National Comprehensive Cancer Network (NCCN) guidelines. Treatment strategies based on PET/CT and conventional imaging were determined by chart review. The maximum and mean standardized uptake values (SUV{sub max}, SUV{sub mean}), metabolic tumor volume (MTV), total lesion glycolysis (TLG), change in SUV{sub max}, change in MTV, and change in TLG were calculated from the PET/CT studies before and after treatment. Response prediction was based on imaging studies performed before and after therapy and categorized as positive or negative for residual tumor. Clinical outcome was determined from chart review. PET/CT was performed for staging in 16 patients, for restaging in 29 patients, and for surveillance in 2 patients. Of the patients, 88 % were correctly staged with PET/CT, whereas 75 % were correctly staged with conventional imaging. The sensitivity to detect local recurrence and distant metastasis at restaging was 100 and 100 % for PET/CT compared to 86 and 83 % for conventional imaging, respectively. PET/CT findings resulted in treatment changes in 31 % (5/16) and 14 % (4/29) of patients at staging and restaging, respectively. Recurrence, MTV, and TLG were prognostic factors for survival, whereas SUV{sub max} and SUV{sub mean} were not predictive. For 21 patients who had imaging studies performed both before and after treatment, PET/CT was better at predicting outcome (overall survival, progression-free survival) than conventional imaging. A decreasing SUV{sub max} ≥ 30 % and decrease in TLG and MTV were significant

  18. Correlation of the CT values of abdominal aorta,renal artery and renal cortex with its thickness on 64-MDCT contrast en-hanced images

    Institute of Scientific and Technical Information of China (English)

    Alomary Mahfooz-Naef; Vikash; Wang Qiu-xia; Zhang Jin-hua; Hu Dao-yu

    2015-01-01

    Objective:To investigate the correlation of abdominal aorta CT value,renal artery CT value and renal cor-tex thickness with renal cortex CT value on contrast enhanced 64-slice CT images.Methods:96 patients (50 men and 46 women;16~74 years)with normal kidney function,which was confirmed by kidney function test were enrolled in this stud-y,including bilateral kidneys of 92 cases and unilateral kidney of 4 cases (total of 188 kidneys;92 left,96 right).After intra-venous (IV)injection of contrast agent the kidneys of the selected patients were scanned by MDCT.The scans were per-formed in arterial,venous and 3min delayed phases.All statistical analyses were performed by using IBM SPSS 20.0.Graphs were generated using Graph Pad Prism 5 software.Quantitative data were presented as mean ± standard deviation,while qualitative data were presented as frequency (%).P<0.05 was considered to be statistically significant.Results:The mean renal cortex thickness was (5.19±0.81)mm in all kidneys.In the arterial phase,a statistically significant positive correla-tion between renal cortex CT values and abdominal aortic CT values was showed (r= 0.584;P<0.001).A statistically sig-nificant positive correlation between renal cortex CT values and renal cortex thickness was demonstrated (r= 0.533,P<0.0001).Likewise,there was a positive correlation between renal cortex CT value and renal artery CT values (r= 0.43,P<0.001).Conclusion:It is a promising approach to assess the individual kidney function by measuring abdominal aorta CT value,renal artery CT value,renal cortex CT value and renal cortex thickness using contrast MDCT.

  19. A comparison of the diagnostic value of MRI and 18F-FDG-PET/CT in suspected spondylodiscitis

    NARCIS (Netherlands)

    Smids, C.; Kouijzer, I.J.E.; Vos, F.J.; Sprong, T.A.; Hosman, A.J.F.; Rooy, de J.W.; Aarntzen, E.H.J.G.; Geus-Oei, de L.; Oyen, W.J.G.; Bleeker-Rovers, Chantal P.

    2017-01-01

    Purpose The purpose of this study was to evaluate the diagnostic value of 18F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT scan) and magnetic resonance imaging (MRI) in diagnosing spondylodiscitis and its complications, such as epidural and paraspinal abscess

  20. A comparison of the diagnostic value of MRI and 18F-FDG-PET/CT in suspected spondylodiscitis

    NARCIS (Netherlands)

    Smids, C.; Kouijzer, I.J.E.; Vos, F.J.; Sprong, T.A.; Hosman, A.J.F.; Rooy, de J.W.; Aarntzen, E.H.J.G.; Geus-Oei, de L.; Oyen, W.J.G.; Bleeker-Rovers, Chantal P.

    2016-01-01

    Purpose The purpose of this study was to evaluate the diagnostic value of 18F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT scan) and magnetic resonance imaging (MRI) in diagnosing spondylodiscitis and its complications, such as epidural and paraspinal abscess

  1. Value of PET/CT and MR lymphography in treatment of prostate cancer patients with lymph node metastases

    NARCIS (Netherlands)

    Fortuin, A.S.; Deserno, W.M.L.L.G.; Meijer, H.J.M.; Jager, G.J.; Takahashi, S.; Debats, O.A.; Reske, S.N.; Schick, C.; Krause, B.J.; Oort, I.M. van; Witjes, A.J.; Hoogeveen, Y.L.; Lin, E.N. van; Barentsz, J.O.

    2012-01-01

    PURPOSE: To determine the clinical value of two novel molecular imaging techniques: (11)C-choline positron emission tomography (PET)/computed tomography (CT) and ferumoxtran-10 enhanced magnetic resonance imaging (magnetic resonance lymphography [MRL]) for lymph node (LN) treatment in prostate cance

  2. MMP-9 inhibitor SB-3CT attenuates behavioral impairments and hippocampal loss after traumatic brain injury in rat.

    Science.gov (United States)

    Jia, Feng; Yin, Yu Hua; Gao, Guo Yi; Wang, Yu; Cen, Lian; Jiang, Ji-Yao

    2014-07-01

    The aim of this study was to evaluate the potential efficacy of SB-3CT, a matrix metallopeptidase 9 inhibitor, on behavioral and histological outcomes after traumatic brain injury (TBI) in rats. Adult male Sprague-Dawley rats were randomly divided into three groups (n=15/group): TBI with SB-3CT treatment, TBI with saline, and sham injury. The TBI model was induced by a fluid percussion TBI device. SB-3CT (50 mg/kg in 10% dimethyl sulfoxide) was administered intraperitoneally at 30 min, 6 h, and 12 h after the TBI. Motor function (beam-balance/beam-walk tests) and spatial learning/memory (Morris water maze) were assessed on post-operative Days 1-5 and 11-15, respectively. Fluoro-Jade staining, immunofluorescence, and cresyl violet-staining were carried out for histopathological evaluation at 24 h, 72 h, and 15 days after TBI, respectively. It was shown that TBI can result in significant behavioral deficit induced by acute neurodegeneration, increased expression of cleaved caspase-3, and long-term neuronal loss. SB-3CT intervention via the current regime provides robust behavioral protection and hippocampal neurons preservation from the deleterious effects of TBI. Hence, the efficacy of SB-3CT on TBI prognosis could be ascertained. It is believed that the current study adds to the growing literature in identifying SB-3CT as a potential therapy for human brain injury.

  3. Diagnostic value of CT in congenital disorders of the great vessels

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Zenju; Morooka, Nobuhiro; Watanabe, Shigeru; Masuda, Yoshiaki; Inagaki, Yoshiaki (Chiba Univ. (Japan). School of Medicine); Yoshida, Hideo

    1983-09-01

    Computed tomographic (CT) studies of the cardiovascular system were performed on 850 cases at our institute during the last five years. The aorta was clearly demonstrated by CT from the aortic root to the bifurcation of the iliac artery, and in most cases the main aortic branches including the coronary, brachiocephalic, common carotid, subclavian, celiac, superior mesenteric, renal and iliac arteries were satisfactorily evaluated. Therefore CT renders us encouraging to detect the abnormality of these arteries. This paper described the CT finings of congenital anomalies of the great vessels in 14 patients with 16 anomalies including two cases of l-corrected transposition of the great vessels, two of double aortic arch, one of aneurysm of the sinus of Valsalva, six of patent ductus arteriosus (PDA) and five of right-sided descending aorta, two of which had double aortic arch aforementioned and the remaining three had dextrocardia. The diagnosis of these abnormalities except for PDA were made only by CT. For instance, l-corrected transposition of the great vessels was diagnosed easily by observing the side-to-side relationship of the great vessels, the aorta is situated to the left and anterior to the pulmonary artery. In the case of double aortic arch, not only the left and right aortic arch, but also the degree of narrowing as well as compression of the trachea and esophagus were well evaluated. The diagnosis of aneurysm of the sinus of Valsalva was made by the characteristically marked dilatation of the aorta at the level of sinus of Valsalva on CT. Only in one case of PDA, the ductus connecting the descending aorta to the left pulmonary artery was demonstrated by CT. Plain CT was well tolerable, but enhanced CT was much more informative to detect cardiovascular abnormalities, and moreover, dynamic CT was rewarding in the detailed evaluation of blood flow in the cardiovascular system.

  4. Incremental value of the CT coronary calcium score for the prediction of coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Genders, Tessa S.S. [Erasmus University Medical Center, Department of Epidemiology, P.O. Box 2040, CA, Rotterdam (Netherlands); Erasmus University Medical Center, Department of Radiology, P.O. Box 2040, CA, Rotterdam (Netherlands); Pugliese, Francesca; Mollet, Nico R.; Meijboom, W. Bob; Weustink, Annick C.; Mieghem, Carlos A.G. van; Feyter, Pim J. de [Erasmus University Medical Center, Department of Radiology, P.O. Box 2040, CA, Rotterdam (Netherlands); Erasmus University Medical Center, Department of Cardiology, P.O. Box 2040, CA, Rotterdam (Netherlands); Hunink, M.G.M. [Erasmus University Medical Center, Department of Epidemiology, P.O. Box 2040, CA, Rotterdam (Netherlands); Erasmus University Medical Center, Department of Radiology, P.O. Box 2040, CA, Rotterdam (Netherlands); Harvard University, Department of Health Policy and Management, Harvard School of Public Health, Boston (United States)

    2010-10-15

    To validate published prediction models for the presence of obstructive coronary artery disease (CAD) in patients with new onset stable typical or atypical angina pectoris and to assess the incremental value of the CT coronary calcium score (CTCS). We searched the literature for clinical prediction rules for the diagnosis of obstructive CAD, defined as {>=}50% stenosis in at least one vessel on conventional coronary angiography. Significant variables were re-analysed in our dataset of 254 patients with logistic regression. CTCS was subsequently included in the models. The area under the receiver operating characteristic curve (AUC) was calculated to assess diagnostic performance. Re-analysing the variables used by Diamond and Forrester yielded an AUC of 0.798, which increased to 0.890 by adding CTCS. For Pryor, Morise 1994, Morise 1997 and Shaw the AUC increased from 0.838 to 0.901, 0.831 to 0.899, 0.840 to 0.898 and 0.833 to 0.899. CTCS significantly improved model performance in each model. Validation demonstrated good diagnostic performance across all models. CTCS improves the prediction of the presence of obstructive CAD, independent of clinical predictors, and should be considered in its diagnostic work-up. (orig.)

  5. Value of the lumbar lordotic angle taken from CT scanogram as an index of back pain

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Hea Sang; Kim, Guk Hee; Kim, Dae Young [Kangnam General Hospital Public Corporation, Seoul (Korea, Republic of)

    1986-10-15

    'Normal' spinal posture is generally accepted as moderate lordosis of the cervical and the lumbar sections of spine and moderate kyphosis of the thoracic and sacrococcygeal sections. Among these normal range of the lumbar lordosis is less well defined. CT is very useful method to identified the bony structure and adjacent soft tissue of the spine, so it is very available method to detect accurate lumbar lordotic angle by using lateral Scanogram. Analysis and comparison of lumbar lordotic angles, crossing angle are drawn each parallel line to the superior end plate of body of 1st. lumbar vertebra and to the inferior end plate of the 5th. lumbar vertebra, in 174 cases with backache and 50 cases normal groups at Kangnam General Hospital Public Corporation, from Aug. 1985 to Jul 1986. Male and female were almostly same affected in backache group (1.1:1). And most lumbar lordotic angles were 10 to 40 between all backache age group. On backache group, over all mean lumbar lordotic angles were 24.7+-8.9 but no significant difference at mean value of the each diseases, such as HIVD, Degenerative Spondylosis or No Remarkable Findings group. On control group, over all mean ones were 29.2+-8.0. So, significant difference of lumbar lordotic angle between backache and control group, and most difference is at 5th. decade group (p 0.01).

  6. Value of CT in the diagnosis and management of gallstone ileus

    Institute of Scientific and Technical Information of China (English)

    Chih-Yung Yu; Cheng-Yu Chen; Chang-Chyi Lin; Rong-Yaun Shyu; Chung-Bao Hsieh; Hurng-Sheng Wu; Yeu-Sheng Tyan; Jen-I Hwang; Chang-Hsien Liou; Wei-Chou Chang

    2005-01-01

    IM: To retrospectively establish the diagnostic criteria of gallstone ileus on CT, and to prospectively apply these criteria to determine the diagnostic accuracy of CT to confirm or exclude gallstone ileus in patients who presented with acute small bowel obstruction (SBO). Another purposewas to ascertain whether the size of ecctopic gallstones would affect treatment strategy.METHODS: Fourteen CT scans in cases of proved gallstone ileus were evaluated retrospectively by two radiologists for the presence or absence of previously reported CT findings to establish the diagnostic criteria. These criteria were applied in a prospective contrast enhanced CT study of 165 patients with acute SBO, which included those 14 cases of gallstone ileus. The hard copy images of 165 CT studies were reviewed by a different group of two radiologists but without previous knowledge of the patient's final diagnosis. All CT data were further analyzed to determine the diagnostic accuracy of gallstone ileus when using CT in prospective evaluation of acute SBO. The size of ectopic gallstone on CT was correlated with the clinical course.RESULTS: The diagnostic criteria of gallstone ileus on CT were established retrospectively, which included: (1) SBO; (2) ectopic gallstone; either rim-calcified or total-calcified; (3) abnormal gall bladder with complete air collection, presence of air-fluid level, or fluid accumulation with irregular wall. Prospectively, CT confirmed the diagnosis in 13 cases of gallstone ileus with these three criteria. Only one false negative case could be identified. The remaining 151 patients are true negative cases and no false positive case could be disclosed. The overall sensitivity, specificity and accuracy of CT in diagnosing gallstone ileus were 93%, 100%; and 99%, respectively. Surgical exploration was performed in 13 patients of gallstone ileus with ectopic stones sized larger than 3 cm. One patient recovered uneventfully following conservative treatment with an

  7. Clinical value of FDG-PET/CT in suspected paraneoplastic syndromes: a retrospective analysis of 137 patients

    Energy Technology Data Exchange (ETDEWEB)

    Bjoern Kristensen, Stine; Hess, Soeren; Petersen, Henrik; Hoeilund-Carlsen, Poul Flemming [Odense University Hospital, Department of Nuclear Medicine, Odense (Denmark)

    2015-12-15

    Paraneoplastic syndromes (PNS) are relatively infrequent manifestations appearing before or after a cancer declares itself. Autoimmune mechanisms may be involved, but their cause and pathogenesis are often unknown. Due to disparity of symptoms, PNS remain a major diagnostic challenge. We examined the value of FDG-PET/CT for ruling in or out malignancy in a heterogeneous group of patients with suspected PNS. We retrospectively extracted data from all patients referred 2009-2013 with suspected PNS. Data included age, sex, follow-up period, scan report, further diagnostic procedures, and final clinical diagnosis. Conclusions of the scan reports were compared to the final follow-up outcome as determined during an average follow-up of 31 months (range 6-51.5) in patients who were not diagnosed with cancer in immediate continuation of a positive PET/CT scan. A total of 137 patients were included. Main causes for referral were neurological (n = 67), rheumatological (n = 25), dermatological (n = 18), nephrological (n = 6), haematological (n = 2), abnormal biochemistry (n = 11), and others (n = 8). The cancer prevalence was 8.8 %. The FDG-PET/CT results were as follows: nine true positives, 22 false positives, 103 true negatives, and three false negatives. Corresponding diagnostic values were: sensitivity 75 %, specificity 82 %, accuracy 82 %, and positive and negative predictive values of 29 % and 97 %, respectively. FDG-PET/CT has in patients with suspected PNS an impressively high negative predictive value and may be of value in ruling out PNS, the more so, the more the number of false positives can be minimized or used in differential diagnosis. We believe that FDG-PET/CT may become an important adjunct to the work-up and triage of patients with suspected PNS. (orig.)

  8. Diagnostic value of F18-FDG PET/CT in patients with the revised definition of fever of unknown origin

    DEFF Research Database (Denmark)

    Prakash, Vineet; Ketharanathan, Nagulabaskaran; Lorenz, Eleanor

    2009-01-01

    enhanced CT. The value of PET/CT in determining the underlying etiology of FUO was retrospectively evaluated by comparing the study findings with a final diagnosis. Final diagnosis was formulated by 6 month clinical, imaging, microbiological and histopathological follow up. When no cause was found...... by follow up, the negative study was considered a true negative. Results: Final diagnosis was made in 35/59 pts. Diagnosis was reached in 86% of these pts with an abnormal study but only in 14% of pts with a normal study. Underlying etiologies included vasculitides (14 pts), infectious foci (14 pts...

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

    Directory of Open Access Journals (Sweden)

    Sukhpreet Dubb

    2008-05-01

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

  10. Diffuse abnormalities of the liver parenchyma: The value of MRI as compared with sonography and CT. Diffuse Leberparenchymerkrankungen: Wertigkeit der KST im Vergleich mit Sonographie und CT

    Energy Technology Data Exchange (ETDEWEB)

    Vogl, T.; Steiner, S.; Hahn, D.; Schedel, H.; Lissner, J. (Muenchen Univ. (Germany, F.R.). Radiologische Klinik Innenstadt)

    1991-05-01

    29 patients with diffuse liver disease were examined by ultrasound, CT and MRI. MRI imaging was performed using T{sub 1}- and T{sub 2}-weighted spin-echo-sequences and fast gradient-echo-sequences. The paramagnetic contrast agent Gd-DTPA was applied intravenously (0.1 mmol/kg). In all patients with hepatitis MRI enabled exact liver biopsy by delineation of inflammatory changes in cases of chronic or focal hepatitis. CT and ultrasound were superior to MRI in the detection of focal or diffuse fatty degeneration. However, MRI enabled an exact differentiation of fatty changes from neoplasm. In cases of fibrotic changes the most accurate findings could be shown by MRI. In patients suffering from hemochromatosis MRI supplied additional information compared to CT and ultrasound revealing significant reduction of signal intensity due to reinforced enhancement of iron. Concerning Wilson's disease MRI showed a characteristic pattern of parenchymal changes. The application of Gd-DTPA in cases of diffuse liver disease adds supplementary information about perfusion of liver parenchyma, but its value for diagnostic accuracy is only secondary. (orig./GDG).

  11. Diagnostic value of CT-colonography as compared to colonoscopy in an asymptomatic screening population: a meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Haan, Margriet C. de [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Academic Medical Center, Amsterdam, Department of Radiology, G1-223.1, Amsterdam (Netherlands); Gelder, Rogier E. van; Bipat, Shandra; Stoker, Jaap [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Graser, Anno [University of Munich, Department of Clinical Radiology, Klinikum Grosshadern, Munich (Germany)

    2011-08-15

    Previous meta-analyses on CT-colonography included both average and high risk individuals, which may overestimate the diagnostic value in screening. A meta-analysis was performed to obtain the value of CT-colonography for screening. A search was performed using PubMed, Embase and Cochrane. Article selection and critical appraisal was done by two reviewers. Inclusion criteria: prospective, randomized trials or cohort studies comparing CT-colonography with colonoscopy ({>=}50 participants), {>=}95% average risk participants {>=}50 years. Study characteristics and 2 x 2 contingency Tables were recorded. Sensitivity and specificity estimates were calculated per patient and per polyp ({>=}6 mm, {>=}10 mm), using univariate and bivariate analyses. Five of 1,021 studies identified were included, including 4,086 participants (<1% high risk). I{sup 2}-values showed substantial heterogeneity, especially for 6-9 mm polyps and adenomas: 68.1% vs. 78.6% (sensitivity per patient). Estimated sensitivities for patients with polyps or adenomas {>=} 6 mm were 75.9% and 82.9%, corresponding specificities 94.6% and 91.4%. Estimated sensitivities for patients with polyps or adenomas {>=} 10 mm were 83.3% and 87.9%, corresponding specificities 98.7% and 97.6%. Estimated sensitivities per polyp for advanced adenomas {>=} 6 mm and {>=} 10 mm were 83.9% and 83.8%. Compared to colonoscopy, CT-colonography has a high sensitivity for adenomas {>=} 10 mm. For (advanced) adenomas {>=} 6 mm sensitivity is somewhat lower. (orig.)

  12. WE-AB-204-04: Feature Selection and Clustering Optimization for Pseudo-CT Generation in MR-Based Attenuation Correction and Radiation Therapy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, J; Su, K [Case Center for Imaging Research, Case Western Reserve University, Cleveland, Ohio (United States); Department of Radiology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio (United States); Hu, L; Traughber, M [Philips Healthcare, Cleveland, Ohio (United States); Pereira, G; Traughber, B [Department of Radiation Oncology, University Hospitals Seidman Cancer Center, Case Western Reserve University, Cleveland, Ohio (United States); Herrmann, K [Department of Radiology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio (United States); Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, Ohio (United States); Muzic, R [Case Center for Imaging Research, Case Western Reserve University, Cleveland, Ohio (United States); Department of Radiology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio (United States); Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH (United States)

    2015-06-15

    Purpose: Accurate and robust photon attenuation derived from MR is essential for PET/MR and MR-based radiation treatment planning applications. Although the fuzzy C-means (FCM) algorithm has been applied for pseudo-CT generation, the input feature combination and the number of clusters have not been optimized. This study aims to optimize both for clinically practical pseudo-CT generation. Methods: Nine volunteers were recruited. A 190-second, single-acquisition UTE-mDixon with 25% (angular) sampling and 3D radial readout was performed to acquire three primitive MR features at TEs of 0.1, 1.5, and 2.8 ms: the free-induction-decay (FID), the first and the second echo images. Three derived images, Dixon-fat and Dixon-water generated by two-point Dixon water/fat separation, and R2* (1/T2*) map, were also created. To identify informative inputs for generating a pseudo-CT image volume, all 63 combinations, choosing one to six of the feature images, were used as inputs to FCM for pseudo-CT generation. Further, the number of clusters was varied from four to seven to find the optimal approach. Mean prediction deviation (MPD), mean absolute prediction deviation (MAPD), and correlation coefficient (R) of different combinations were compared for feature selection. Results: Among the 63 feature combinations, the four that resulted in the best MAPD and R were further compared along with the set containing all six features. The results suggested that R2* and Dixon-water are the most informative features. Further, including FID also improved the performance of pseudo-CT generation. Consequently, the set containing FID, Dixon-water, and R2* resulted in the most accurate, robust pseudo-CT when the number of cluster equals to five (5C). The clusters were interpreted as air, fat, bone, brain, and fluid. The six-cluster Result additionally included bone marrow. Conclusion: The results suggested that FID, Dixon-water, R2* are the most important features. The findings can be used to

  13. 螺旋CT 在消化道穿孔中的诊断价值%Diagnostic value of spiral CT for gastrointestinal perforation

    Institute of Scientific and Technical Information of China (English)

    周晓秋; 王宝春; 操啸; 刘云峰

    2014-01-01

    目的:分析C T在消化道穿孔中的诊断价值。方法回顾性分析51例经手术证实的消化道穿孔病例,术前行立位腹部平片检查者41例,腹部C T扫描者51例,比较两种检查方法在消化道穿孔中的诊断价值。结果41例X线片检出游离气体26例,CT检出50例,CT检出率高于普通X线检查( P <0.05)。CT显示腹内游离气体呈新月状或小气泡影(50例),胃肠穿孔处周围局限性积液或蜂窝织炎(34例),阑尾周围脓肿(3例),肠梗阻(5例),胃肠壁增厚(25例),胃肠壁肿块(2例),胃肠壁缺损(4例),腹水(30例)。C T对穿孔病因的诊断符合率为68.6%(35/51),对穿孔部位的诊断符合率为88.2%(45/51)。结论螺旋C T诊断胃肠道穿孔是一种有效的检查方法,且对穿孔部位和病因的诊断也具有重要价值。%Objective To analyze the value of Spiral CT in the diagnosis of gastrointestinal (GI) tract perforation .Meth-ods 51 cases that had gastrointestinal tract perforation confirmed by surgery were retrospectively studied in this research . All these cases had CT examination and 41 cases had abdominal plain film examination on the same day .Moreover ,the di-agnostic value of the two methods in gastrointestinal (GI) tract perforation was compared .Results Free air was only shown in 26 cases out of 41 by X-ray examination ,but 50 cases out of 51 by Spiral CT examination .CT examination detec-tion rate was higher than ordinary X-ray examination ( P<0 .05) .The direct CT sign of gastrointestinal tract perforation was“crescent”or“bubble”sign formed by the air within peritoneal cavity ,which were detected in 50 cases .The other find-ings were showing the localized fluid or cellulites adjacent to the gastrointestinal tract perforation (n=34) and appendiceal abscess (n=3) .5 cases were associated with bowel obstruction ,25 cases with gastrointestinal wall thickening ,2 cases

  14. Case of asymmetrical arthrogryposis. A clinical study and a preliminary report on the value of CT-scanning

    Energy Technology Data Exchange (ETDEWEB)

    Hageman, G.; Vette, J.K.; Willemse, J. (University Hospital, Utrecht (Netherlands))

    1983-01-01

    Following the introduction of the conception that arthrogryposis is a symptom and not a clinical entity, a case of the very rare asymmetric form of neurogenic arthrogryposis is presented. The asymmetry of congenital contractures and weakness is associated with hemihypotrophy. The value of muscular CT-scanning prior to muscle biopsy is demonstrated. Muscular CT-scanning shows the extension of adipose tissue, which has replaced damaged muscles and therby indicates the exact site for muscle biopsy. Since orthopaedic treatment in arthrogryposis can be unrewarding due to severe muscular degeneration, preoperative scanning may provide additional important information on muscular function and thus be of benefit for surgery. The advantage of muscular CT-scanning in other forms of arthrogryposis requires further determination. The differential diagnosis with Werdnig-Hoffmann disease is discussed.

  15. The Values and Limitations of FDG-PET/CT for Diagnosis of Hibernoma

    Directory of Open Access Journals (Sweden)

    Jong Hoon Park

    2015-01-01

    Full Text Available Hibernoma is a rare benign lipogenic tumor of brown fat that develops in a wide variety of locations. Although the features of hibernoma demonstrated by MRI resemble those of liposarcoma, recent FDG-PET/CT studies have documented higher radiotracer uptake than liposarcoma, suggesting that FDG/PET/CT is useful for differentiating hibernoma from liposarcoma. Here we report two cases of hibernoma that showed relatively lower SUVs than those reported previously, lying within the range for liposarcoma. Our findings emphasize that hibernoma needs to be included in the differential diagnosis of any fat-containing tumor showing intense accumulation by FDG-PET/CT. Although it is unlikely that such a rare condition could be reasonably diagnosed on the basis of MRI and FDG-PET/CT alone due to possible SUV overlap between hibernoma and liposarcoma, it is important to recognize this extremely rare lipogenic tumor for accurate diagnosis and appropriate management.

  16. Diagnosis and Clinical Value of CT on Brain Abscess%脑脓肿CT诊断的临床分析

    Institute of Scientific and Technical Information of China (English)

    高廷军; 李涛

    2015-01-01

    Objective To probe manifest actions of brain abscess on CT and clinical value of CT in brain abscess. Methods CT feature in 29 patients pathologically o r clinically proved were retro spectively analyzed. Results 25 cases of CT examination for the ifrst time to make a deifnite diagnosis, the other 4 cases after 7-15 d, review of the diagnosis of brain abscess. Conclusion CT has characteristic manifestations on brain abscess. It should be the ifrst choice for t he diagnosis.%目的: CT对脑脓肿的诊断价值和临床意义。方法分析29例经手术病理和临床证实的脑脓肿的CT表现及临床,得出CT对于临床诊断疗效。结果25例首次CT检查就做出明确诊断,另4例经7~15 d后复查,诊断为脑脓肿。结论脑脓肿CT表现有一定特征性,是诊断脑脓肿首选方法。

  17. 18F-FDG-PET/CT in fever of unknown origin: clinical value.

    Science.gov (United States)

    Buch-Olsen, Karen M; Andersen, Rikke V; Hess, Søren; Braad, Poul-Erik; Schifter, Søren

    2014-09-01

    Fever of unknown origin continues to be a diagnostic challenge for clinicians. The aim of this study was to confirm whether (18)F-fluorodeoxyglucose ((18)F-FDG)-PET/computed tomography (CT) is a helpful tool in patients suffering from this condition. Fifty-seven patients with fever of unknown origin were examined with (18)F-FDG-PET/CT as part of their diagnostic workup at the clinicians' discretion. The medical records were read retrospectively to establish the final diagnosis and evaluate the degree to which PET/CT contributed to the diagnosis. The examination was considered helpful if it corresponded to the final diagnosis by showing uptake in an organ considered responsible for the condition, or if it was without focal findings, thereby excluding the patient from having focal infection or malignancy. It was perceived false positive if it pointed towards an organ not regarded by the clinicians as being related to the final diagnosis. It was perceived not helpful if the cause of fever was not visible on (18)F-FDG-PET/CT. We found (18)F-FDG-PET/CT helpful in 75% of patients, not helpful in 4%, and false positive in 21% of patients. (18)F-FDG-PET/CT is a useful tool in the investigation of fever of unknown origin; it can reduce patient inconvenience and possibly costs to society if used earlier in the diagnostic process.

  18. [The value of dual-source dual-energy CT with iodine overlay in the diagnosis of acute necrotizing pancreatitis].

    Science.gov (United States)

    Yuan, Yuan; Huang, Zi-Xing; Li, Zhen-Lin; Song, Bin; Deng, Li-Ping

    2012-07-01

    To investigate the clinical value of dual-source computed tomography dual-energy Iodine overlay technique in the imaging diagnosis of acute necrotizing pancreatitis. The imaging data were retrospectively analyzed in 67 cases of acute necrotizing pancreatitis underwent contrast-enhanced dual-source dual-energy CT in portal venous phase. The CT imaging parameters, including the difference of CT value between pancreatic parenchyma and necrotic lesion, contrast-to-noise ratio of pancreatic parenchyma-to-necrosis, area of pancreatic necrosis and score of subjective diagnosis, were measured and assessed on CT images of 80 kV, 140 kV, weighted-average 120 kV as well as Iodine overlay. The differences of CT value between pancreatic parenchyma and necrosis in the images of 80 kV, 140 kV, weighted-average 120 kV and Iodine overlay were (67.40 +/- 20.82) HU, (42.87 +/- 14.99) HU, (48.69 +/- 15.82) HU, (33.01 +/- 10.26) HU, respectively; contrast-to-noise ratios of pancreatic parenchyma-to-necrosis of each group were 8.36 +/- 3.58, 5.85 +/- 2.65, 7.68 +/- 3.51, 10.60 4.34; area of pancreatic necrosis of each group was (3.78 +/- 2.68) cm2, (3.28 +/- 2.59) cm2, (3.37 +/- 2.46) cm2, (2.42 +/- 1.98) cm2; the score of subjective diagnosis of each group was 3.88 +/- 0.33, 3.31 +/- 0.80, 3.58 +/- 0.66, 2.81 +/- 0.76, respectively. The four indexes in the images of Iodine overlay were significantly different from those of another three groups (P overlay was significantly higher than that of another three groups, while the difference of CT value, area of pancreatic necrosis and score of subjective diagnosis were lower. CONCLUSION; Dual-source CT dual-energy Iodine overlay is not helpful to improve subjective judgment in the diagnosis of pancreatic necrosis, but contributes to the display of hypoperfusion area around the necrosis.

  19. Diagnostic value of the anterior chamber depth of a globe on CT for detecting open-globe injury

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong Yun; Lee, Jeong Hyun; Choi, Byung Se; Choi, Jin Woo; In, Hyun Sin; Kim, Sun Mi; Baek, Jung Hwan [University of Ulsan College of Medicine, Asan Medical Centre, Department of Radiology and Research Institute of Radiology, Seoul (Korea); Lee, Yong Jae [University of Ulsan College of Medicine, Asan Medical Centre, Department of Ophthalmology, Seoul (Korea)

    2010-05-15

    To determine the diagnostic value of the anterior chamber depth (ACD) of a globe as seen on CT for detecting open-globe injury. We enrolled 28 patients with unilateral open-globe injury confirmed by surgery and 28 controls with other types of orbital trauma. The diagnostic value of the difference of the ACDs between globes was evaluated by ROC analysis. The diagnostic performance of the following CT findings suggesting open-globe injury was also determined from independent analysis by two readers, i.e. change in the ACD and the globe contour, obvious volume loss of the globe, dislocated/deformed lens, intraocular foreign body/air and intraocular haemorrhage. The ACD measurements were possible only in 15 patients with open-globe injuries. A difference in the ACDs{>=}0.4 mm resulted in 0.85 of the area under the ROC curve with a sensitivity of 73% and specificity of 100% (p=0.0001). The presence of one or more of the CT findings had a sensitivity of 92%, specificity of 85% and diagnostic accuracy of 89%. Change in the ACD is a helpful CT finding for detecting open-globe injury. A difference in the ACDs {>=}0.4 mm is a helpful diagnostic criterion with excellent specificity. (orig.)

  20. 结节性硬化症的CT诊断价值%Value of CT diagnosis of tuberous sclerosis

    Institute of Scientific and Technical Information of China (English)

    殷文兵; 汪大武; 张子林

    2012-01-01

    目的 探讨CT在结节性硬化诊断中的价值.方法 回顾性分析9例结节性硬化症患者的CT 资料.结果 9例患者均可见侧脑室周围的钙化结节,2例皮层及皮层下多发结节,2例合并肾脏错构瘤.结论 室管膜下多发钙化结节为结节性硬化症在脑内的典型CT表现,对诊断该病具有重要价值.%Objective To explore the value of CT in the diagnosis of tuberous sclerosis ( TSC ). Methods The CT performance of 9 patients with tuberous sclerosis was analysed retrospectively. Results Of 9 cases, periventricular calcified nodules were seen in all patients, multiple nodules in 2 cases of cortical and subcortical, renal hamartoma in 2 patients. Conclusion Multiple subependymal calcified nodules is a typical CT findings of tuberous sclerosis in brain, and it is of great value to the diagnosis of the disease.

  1. A comparison of the diagnostic value of MRI and (18)F-FDG-PET/CT in suspected spondylodiscitis.

    Science.gov (United States)

    Smids, Carolijn; Kouijzer, Ilse J E; Vos, Fidel J; Sprong, Tom; Hosman, Allard J F; de Rooy, Jacky W J; Aarntzen, Erik H J G; de Geus-Oei, Lioe-Fee; Oyen, Wim J G; Bleeker-Rovers, Chantal P

    2017-02-01

    The purpose of this study was to evaluate the diagnostic value of (18)F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT scan) and magnetic resonance imaging (MRI) in diagnosing spondylodiscitis and its complications, such as epidural and paraspinal abscesses. From January 2006 to August 2013 patients with a clinical suspicion of spondylodiscitis, with an infection, or with fever of unknown origin were retrospectively included if (18)F-FDG-PET/CT and MRI of the spine were performed within a 2-week time span. Imaging results were compared to the final clinical diagnosis and follow-up data were collected. Sixty-eight patients were included of whom 49 patients were diagnosed with spondylodiscitis. MRI showed an overall sensitivity of 67 % and specificity of 84 %. Diagnostic accuracy was 58 %, when MRI was performed within 2 weeks after the start of symptoms and improved to 82 %, when performed more than 2 weeks after onset of symptoms. (18)F-FDG-PET/CT showed a sensitivity of 96 % and a specificity of 95 %, with no relation to the interval between the scan and the start of symptoms. As compared to MRI, (18)F-FDG-PET/CT has superior diagnostic value for detecting early spondylodiscitis. After 2 weeks both techniques perform similarly.

  2. Prognostic value of interim 18F-FDG PET/CT in diffuse large B-cell lymphoma

    Institute of Scientific and Technical Information of China (English)

    Zhitao Ying; Xuejuan Wang; Yuqin Song; Wen Zheng; Xiaopei Wang; Yan Xie; Ningjing Lin

    2013-01-01

    Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease.The prognostic factor currently used is not accurate enough to predict the outcomes of patients with DLBCL.The prognostic significance of interim PET/CT in DLBCL remains controversial.The aim of this study is to determine the predictive value of interim 18F-FDG PET/CT after first-line treatment in patients with DLBCL.Methods:Thirty-two patients with DLBCL underwent baseline,interim and post-treatment 18F-FDG PET/CT scans.Imaging results were analyzed for the survival of patients via software SPSS 13.0,retrospectively.Results:Thirty-one of the 32 patients were treated with R-CHOP regimen,and interim 18F-FDG PET/CT of 24 patients was performed after 2 cycles of treatment.After a median follow-up period of 16.7 months,the 2-year progression-free survival (PFS) rates were significandy different between the groups above and below SUVmax cut-off value of 2.5 (P=0.039).No significant differences were found in the 2-year PFS rates if SUVmax cut-offvalues were set as 2.0 and 3.0,respectively (P=0.360; P=0.113).Conclusions:Interim PET/CT could predict the prognosis of DLBCL patients with the SUVmax cut-off value of 2.5,but more clinical data should be concluded to confirm this conclusion.

  3. SPECT/CT - Technical aspects and optimization possibilities; SPECT/CT - Technische Aspekte und Optimierungsmoeglichkeiten

    Energy Technology Data Exchange (ETDEWEB)

    Roemer, W. [Klinikum Passau, Klinik fuer Nuklearmedizin, Passau (Germany)

    2012-07-15

    In contrast to positron emission tomography/computed tomography (PET/CT), the currently available single photon emission computed tomography/computed tomography (SPECT/CT) systems are very heterogeneous. On the side of the gamma cameras, dual-head systems are established, which are not very different from one manufacturer to the other. For the CT component, there are low dose tubes on the one side and flat detector-based cone beam CT and multislice-CT on the other. The CT image data can be used for anatomic correlation of suspicious findings as well as for attenuation correction of SPECT data. Attenuation correction enables on the one hand enhancement of SPECT image quality and on the other hand quantification of the radioactivity concentration becomes possible. Modern iterative reconstruction algorithms allow scatter correction and attenuation correction of SPECT data using the density values from CT. It still has to be shown to what extent attenuation-corrected whole body SPECT/CT studies will be able to improve the sensitivity of scintigraphy studies. As SPECT/CT primarily aims at morphologic correlation and not detection of additional lesions, an attempt should be made to balance the necessary anatomic information and the additional radiation exposure. Besides SPECT-guided CT all technical possibilities for dose reduction should be exhausted. (orig.) [German] Im Gegensatz zur Positronenemissionstomographie/Computertomographie (PET/CT) sind die auf dem Markt angebotenen Single-photon-emission-computed-tomography/CT(SPECT/CT)-Systeme sehr heterogen. Auf der Seite der Gammakameras sind Zweikopfsysteme etabliert, die sich bei den verschiedenen Wettbewerbern nur unwesentlich unterscheiden. Hingegen reicht bei der CT-Komponente die Palette von der einfachen Niedrigdosisroentgenroehre ueber die flachdetektorbasierte Cone-beam-CT-Technologie bis hin zum Mehrzeilenspiral-CT. Die CT-Bilddaten werden dabei zum einen zur anatomischen Korrelation funktionell auffaelliger

  4. The Value of Calcium-scoring CT for Ischemic Cardiovascular Disease Screening

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Jung Hoan; An, Sung Min [Dept. of Radiological Science, Gachon University Science and Health, Incheon (Korea, Republic of)

    2009-03-15

    The cardiovascular disease has been known as a common cause of death for a long time in the west. The eating habits of Asia, including Korea, have changed recently, so that this disease is also a problem in Asia now. Annual Report on the Cause of Death Statistics from 1996 to 2006 reported that the cardiovascular disease would become the number one cause of death in the next years. Therefore we realize that more accurate examination is required. The aim of this study was to investigate the accuracy of Calcium-scoring CT and the relationship between risk factor and quantitative scores of Calcium-scoring CT. Through this study we expect that the national public health will be improved. Seventy patients with chest pain were chosen at random. The patients were undergone both coronary CT antigraphy and Calcium - scoring CT at G hospital in Incheon from February 1 to June 30, 2008. The result of the Calcium-scoring CT showed its usefulness for Ischemic cardiovascular disease, with an accuracy similar to that of exercise/pharmacologic stress or ECG when it is difficult for a patient to exercise due to joint problems, aging or for other reasons.

  5. The added value of multislice SPECT/CT in patients with equivocal bony metastasis from carcinoma of the prostate

    Energy Technology Data Exchange (ETDEWEB)

    Helyar, Vincent [King' s College London, School of Medicine, Taunton, Somerset (United Kingdom); Mohan, Hosahalli K.; Barwick, Tara; Livieratos, Lefteris; Gnanasegaran, Gopinath; Clarke, Susan E.M.; Fogelman, Ignac [Guy' s and St Thomas' NHS Foundation Trust, Department of Nuclear Medicine, London (United Kingdom)

    2010-04-15

    The purpose of this study was to investigate the additional value of single photon emission computed tomography/computed tomography (SPECT/CT) over whole-body planar bone scintigraphy and SPECT in prostate cancer patients in terms of diagnostic confidence, inter-reviewer agreement and the possible impact on the clinical management. This was a retrospective review of 40 consecutive prostate cancer patients (mean age 71 years) who underwent {sup 99m}Tc-methylene diphosphonate (MDP) whole-body planar bone scintigraphy, SPECT and SPECT/CT between April 2006 and April 2008. The images were evaluated by two independent reviewers; inter-reviewer agreement was evaluated using a weighted kappa score. Each focus of abnormal increased tracer uptake was recorded using a 4-point diagnostic confidence scale. Institutional Review Board approval was obtained. Fifty lesions on planar bone scintigraphy in the 40 patients were evaluated. On reporting the planar study and SPECT scans, reviewers rated 61% of lesions as equivocal. On reporting the SPECT/CT scans only 8% of lesions were rated as equivocal, 24% were rated as malignant and 68% as benign. Weighted kappa scores for inter-reviewer agreement were 0.43 for bone scintigraphy, 0.56 for SPECT and 0.87 for SPECT/CT. All were significant at p < 0.0001. Follow-up imaging confirmed the SPECT/CT diagnoses in 14 patients. The addition of SPECT/CT resulted in a significant reduction of equivocal reports; a definitive diagnosis was given in the majority of the patients due to the improved diagnostic confidence compared to planar or SPECT imaging alone in prostate cancer patients with suspected bone metastases. (orig.)

  6. TU-EF-204-08: Dose Efficiency of Added Beam-Shaping Filter with Varied Attenuation Levels in Lung-Cancer Screening CT

    Energy Technology Data Exchange (ETDEWEB)

    Ma, C; Yu, L; Vrieze, T; Leng, S; Fletcher, J; McCollough, C [Mayo Clinic, Rochester, MN (United States)

    2015-06-15

    Purpose: Added filtration such as tin filter has the potential to improve dose efficiency of x-ray beam in lung-cancer screening CT. However, dose efficiency with added beam filtration is highly dependent on patient attenuation level. In this phantom study, we evaluated the image quality at different tube voltages with and without added tin filter when attenuation level varies. Methods: A 30 x 20 cm anthropomorphic thorax phantom with three added extension rings were used to simulate small (S), medium (M), large (L), and extra-large (XL) adult patients. These phantoms were scanned on a 192-slice CT scanner (Force, Siemens) at 100 and 120kV without tin filtration, and 100 and 150 kV with tin filtration (100Sn and 150Sn), at multiple dose levels at each kV. Images were reconstructed using iterative reconstruction (ADMIRE, Siemens). Radiation dose was measured with a 0.6 cc ion chamber in the middle and peripheral areas of the phantom. Image quality was assessed using mean image noise at uniform areas in the central region and lung. Radiation dose that is required for each kV to match the noise in a routine lung-cancer CT screening technique (120kV, 25 quality reference mAs) was calculated. Results: At each of the four phantom sizes, 100Sn had the lowest noise in both soft tissue and lung. Compared with 120 kV, 100Sn saved 39%–60% dose for the same noise, depending on phantom size. For the XL phantom (50 by 40 cm), 150Sn provided images with the least beam-hardening artifact in peripheral region. Conclusion: For thoracic CT, added tin filtration can provide considerable dose reduction compared with 120 kV. 100Sn provides better dose efficiencies for all phantom sizes, while 150Sn provides better image quality in peripheral region for extra-large patients. Drs.Joel G. Fletcher and Cynthia H. McCollough receive research support from Siemens Healthcare.

  7. Value and limits of μ-CT for nondemineralized bone tissue processing.

    Science.gov (United States)

    Draenert, Miriam Esther; Draenert, Alice Irène; Forriol, Francisco; Cerler, Michael; Kunzelmann, Karl-Heinz; Hickel, Reinhard; Draenert, Klaus

    2012-04-01

    An experimental approach was performed on 20 giant rabbits to establish the possibilities and limitations of μ-CT for routine processing of nondemineralized bone tissue. Hydroxyapatite (HA) or β-tricalciumphosphate (β-TCP) bead implants or a melange of both, microchambered and solid, were implanted into a standardized and precise defect in the patellar groove. The bone-healing phase was chosen for the histology considering 1 or 2 days, and 2, 3, and 6 weeks. Normal X-ray and μ-CT were applied on all specimens; five specimens in the 6-week stage were additionally processed according to the full range of conventional nondemineralized bone processing methods. μ-CT increased the possibilities of nondemineralized histology with respect to bone morphometry and a complete sequence of sections, thus providing a complete analysis of the bone response. μ-CT was limited in differentiating bone quality, cell analyses, and mineralization stages. The investigation based on normal X-rays is limited to defining integration and excluding the fibrous and bony encapsulation of loose implants. μ-CT allows a 3D evaluation of newly formed bone which is clearly marked against the ceramic implant. It does not allow, however, for the differentiation between woven and lamellar bone, the presentation of the canalicular lacunar system, or on the cell level, revealing canaliculi or details of the mineralization process which can be documented by high-resolution microradiography. Titer dynamics of bone formation remains the domain of polychromatic sequential labeling. The complete sequence of μ-CT slices enhances the possibilities for routine histology, tremendously allowing to the focus on detail histology to topographically well-defined cuts, thus providing more precise conclusions which take into consideration the whole implant.

  8. Subperiosteal chondroma. Diagnostic value of CT scan imaging in two cases

    Energy Technology Data Exchange (ETDEWEB)

    Lerais, J.M.; Auquier, F.; Baudrillard, J.C.; Durot, J.F.; Laugareil, P.; Wallays, C.; Lefort, G.; Daoud, S.; Gaillard, D.

    1988-01-01

    Results of CT scan exploration are reported in two cases of subperiosteal chondroma, one in a 4 year old child affecting the anterior tibial tuberosity the other in a 9 year old child involving the upper end of humerus. Data from CT scan imaging were undoubtedly superior to those of conventional radiography and appear to be characteristic of this benign cartilaginous tumor, greatly facilitating correlation between clinical, radiological and pathologic findings. The scanner should allow certain situations to be dedramatized and the surgical attitude adapted when the functional prognosis is involved.

  9. Spiral CT arthrography of the knee: technique and value in the assessment of internal derangement of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Berg, Vande B.C.; Lecouvet, F.E.; Maldague, B.; Malghem, J. [Department of Radiology, Cliniques Universitaires St. Luc, Universite Catholique de Louvain, Brussels (Belgium); Poilvache, P. [Department of Orthopedic Surgery, Cliniques Universitaires St. Luc, Universite Catholique de Louvain, Brussels (Belgium)

    2002-07-01

    Computed tomography imaging has achieved excellent multiplanar capability and submillimeter spatial resolution due to the development of the spiral acquisition mode and multidetector row technology. Multidetector spiral CT arthrography (CTA) yields valuable information for the assessment of internal derangement of the joints. This article focuses on the value of spiral CTA of the knee in the assessment of the meniscus, anterior cruciate ligament, and hyaline cartilage lesions. Advantages and disadvantages of spiral CTA with respect to MR imaging are presented. (orig.)

  10. Value of {sup 18}F-FDG PET/CT in the diagnosis of primary gastric cancer via stomach distension

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Quanmei, E-mail: 444656285@qq.com [Department of Radiology, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Xin, Jun, E-mail: xinj@sj-hospital.org [Department of Radiology, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Zhao, Zhoushe, E-mail: zhoushe.zhao@ge.com [GE, Shenyang 110004 (China); Guo, Qiyong, E-mail: guoqy@vip.sina.com [Department of Radiology, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Yu, Shupeng, E-mail: drizzleyu@163.com [Department of Nuclear Medicine, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Xu, Weina, E-mail: xuwn@sj-hospital.org [Department of Nuclear Medicine, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Liu, Changping, E-mail: liucp1698@163.com [Department of Nuclear Medicine, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Zhai, Wei, E-mail: zhw69@163.com [Department of Nuclear Medicine, Shengjing Hospital of China Medical University, Shenyang 110004 (China)

    2013-06-15

    Objective: To clarify the usefulness of {sup 18}F-FDG PET/CT for detecting primary gastric cancer via gastric distention using a mixture of milk and Diatrizoate Meglumine. Materials and methods: A total of 68 patients (male: 47, female: 21; age: 41–87 years) suspected of gastric carcinoma underwent {sup 18}F-FDG PET/CT imaging. After whole-body PET/CT imaging in a fasting state, the patients drank a measured amount of milk with Diatrizoate Meglumine. Local gastric district PET/CT imaging was performed 30 min later. The imaging was analyzed by semi-quantitative analysis, standardized uptake value (SUV) of the primary tumor was measured in a region of interest. The diagnosis results were confirmed by gastroscopy, pathology, and follow-up results. Results: Of the 68 patients, 56 malignant gastric neoplasm patients (male: 37, female: 19) were conformed. The sensitivity, specificity, positive predictive value and negative predictive value of fasting whole-body PET/CT imaging for a primary malignant tumor were 92.9%, 75.0%, 94.5%, and 69.0%, respectively. The values for distension with a mixture of milk and Diatrizoate Meglumine were 91.1%, 91.7%, 98.1%, and 68.8%, respectively. The area under the curve was 0.919 ± 0.033 and 0.883 ± 0.066 for the diagnosis of gastric cancer with SUV{sub max} in a fasting state and after intake of mixture respectively, the differences were not statistically significant (P = 0.359). Using gastric distension with a mixture of milk and Diatrizoate Meglumine, the mean ratio of the lesion's SUV{sub max} to the adjacent gastric wall SUV{sub max} increased significantly from 3.30 ± 3.05 to 13.50 ± 15.05, which was statistically significant (P < 0.001). Conclusions: {sup 18}F-FDG PET/CT imaging is highly accurate for the diagnosis of primary gastric carcinoma. Gastric distention can display the lesions more clearly, however, it cannot significantly improve diagnostic accuracy.

  11. [Value of (99)Tc(m)-MDP SPECT/CT in clinical decision-making for nasopharyngeal carcinoma and a comparison of the values of different imaging techniques for diagnosing skull-base bone invasion].

    Science.gov (United States)

    Li, W; Zhang, R S; Zhang, L Q; Lu, B G; Fu, W H

    2017-02-23

    Objective: To analyze the clinical value of SPECT/CT in diagnosis of skull base bone invasion and clinical decision-making for nasopharyngeal carcinoma (NPC), and to compare their diagnostic value with SPECT/CT, CT, MRI, and MRI combined with SPECT (MRI-SPECT) for skull base bone invasion. Methods: Before treatment, among 348 newly diagnosed NPC patients, CT scan was performed in 186 patients (group A) and the remaining 162 patients received MRI scan (group B). Clinical doctors then made clinical management decisions according to the CT or MRI results. After that, all patients underwent (99)Tc(m)-MDP SPECT/CT examination for nasopharyngeal local tomography, and the results were provided to the clinical doctors to make clinical management decisions again. The changes between the two clinical management decisions were scored according to diagnosis, range of lesion, staging, treatment regimens, and auxiliary examination. The diagnostic value of CT scan, MRI scan, SPECT/CT and MRI-SPECT for skull base bone invasion was then evaluated and compared. Results: In terms of changes in scores of clinical management decisions, the score of group A was 1.387 and group B was 0.951, showing a significant difference between the two groups by Wilcoxon test (Z=6.570, P<0.001). By χ(2) test, there were correlations between CT and SPECT/CT (χ(2) =98.495, P<0.001), and between MRI and SPECT/CT (χ(2) =32.662, P<0.001). The consistency of CT and SPECT/CT (Kappa=0.713) was greater than MRI and SPECT (Kappa=0.449). The sensitivity of CT, MRI, SPECT/CT and MRI-SPECT was 67.1%, 84.5%, 90.8% and 100%, the specificity was 73.3%, 92.3%, 85.6% and 84.6%, and the area under the ROC curve was 0.702, 0.884, 0.882 and 0.923, respectively. Conclusions: SPECT/CT has important impact on clinical management decision for NPC. In the judgement of skull base invasion, the diagnostic value of SPECT/CT is significantly higher than CT and approximately equal to MRI. SPECT/CT should be one of the routine

  12. CT quantification of lung and airways in normal Korean subjects

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Song Soo; Lee, Jeong Eun; Shin, Hye Soo [Dept. of Radiology, Chungnam National University Hospital, Chungnam National University School of Medicine, Daejeon (Korea, Republic of); Jin, Gong Yong; Li, Yuan Zhe [Dept. of Radiology, Research Institute of Clinical Medicine of Chonbuk National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju (Korea, Republic of)

    2017-08-01

    To measure and compare the quantitative parameters of the lungs and airways in Korean never-smokers and current or former smokers (“ever-smokers”). Never-smokers (n = 119) and ever-smokers (n = 45) who had normal spirometry and visually normal chest computed tomography (CT) results were retrospectively enrolled in this study. For quantitative CT analyses, the low attenuation area (LAA) of LAA{sub I-950}, LAA{sub E-856}, CT attenuation value at the 15th percentile, mean lung attenuation (MLA), bronchial wall thickness of inner perimeter of a 10 mm diameter airway (Pi10), total lung capacity (TLC{sub CT}), and functional residual capacity (FRC{sub CT}) were calculated based on inspiratory and expiratory CT images. To compare the results between groups according to age, sex, and smoking history, independent t test, one way ANOVA, correlation test, and simple and multiple regression analyses were performed. The values of attenuation parameters and volume on inspiratory and expiratory quantitative computed tomography (QCT) were significantly different between males and females (p < 0.001). The MLA and the 15th percentile value on inspiratory QCT were significantly lower in the ever-smoker group than in the never-smoker group (p < 0.05). On expiratory QCT, all lung attenuation parameters were significantly different according to the age range (p < 0.05). Pi10 in ever-smokers was significantly correlated with forced expiratory volume in 1 second/forced vital capacity (r = −0.455, p = 0.003). In simple and multivariate regression analyses, TLC{sub CT}, FRC{sub CT}, and age showed significant associations with lung attenuation (p < 0.05), and only TLC{sub CT} was significantly associated with inspiratory Pi10. In Korean subjects with normal spirometry and visually normal chest CT, there may be significant differences in QCT parameters according to sex, age, and smoking history.

  13. Optimization of iterative reconstruction parameters with attenuation correction, scatter correction and resolution recovery in myocardial perfusion SPECT/CT

    OpenAIRE

    Okuda, Koichi; Nakajima, Kenichi; Yamada, Masato; Wakabayashi, Hiroshi; Ichikawa, Hajime; Arai, Hiroyuki; Matsuo, Shinro; Taki, Junichi; Hashimoto, Mitsumasa; Kinuya, Seigo

    2014-01-01

    Objective: The aim of this study was to characterize the optimal reconstruction parameters for ordered-subset expectation maximization (OSEM) with attenuation correction, scatter correction, and depth-dependent resolution recovery (OSEMACSCRR). We assessed the optimal parameters for OSEMACSCRR in an anthropomorphic torso phantom study, and evaluated the validity of the reconstruction parameters in the groups of normal volunteers and patients with abnormal perfusion. Methods: Images of the ant...

  14. Value of CT-guided core-needle biopsy in diagnosis and classification of malignant lymphomas using automated biopsy gun

    Institute of Scientific and Technical Information of China (English)

    Li Li; Qiu-Liang Wu; Li-Zhi Liu; Yun-Xian Mo; Chuan-Miao Xie; Lie Zheng; Lin Chen; Pei-Hong Wu

    2005-01-01

    AIM: To evaluate the value of CT-guided core-needle biopsy in diagnosis and classification of malignant lymphomas.METHODS: From January 1999 to October 2004, CT-guided core-needle biopsies were performed in 80 patients with suspected malignant lymphoma. Biopsies were performed with an 18-20 G biopsy-cut (CR Bard, Inc., Covington, GA,USA) needle driven by a spring-loaded Bard biopsy gun.RESULTS: A definite diagnosis and accurate histological subtype were obtained in 61 patients with a success rate of 76.25% (61/80). Surgical sampling was performed in 19 patients (23.75%) with non-diagnostic core-needle biopsies. The success rate of CT-guided core-needle biopsy varied with the histopathologic subtypes in our group.The relatively high success rates of core-needle biopsy were noted in diffuse large B-cell non-Hodgkin's lymphoma (NHL, 88.89%) and peripheral T-cell NHL (90%). However,the success rates were relatively low in anaplastic large cell (T/null cell) lymphoma (ALCL, 44.44%) and Hodgkin's disease (HD, 28.57%) in our group.CONCLUSION: CT-guided core-needle biopsy is a reliable means of diagnosing and classifying malignant lymphomas,and can be widely applied in the management of patients with suspected malignant lymphoma.

  15. Imaging of ceramic liner fractures in total hip arthroplasty: the value of CT

    Energy Technology Data Exchange (ETDEWEB)

    Endo, Yoshimi; Mintz, Douglas N. [Hospital for Special Surgery, Department of Radiology and Imaging, New York, NY (United States); Renner, Lisa; Schmidt-Braekling, Tom; Boettner, Friedrich [Hospital for Special Surgery, Adult Reconstruction and Joint Replacement Division, New York, NY (United States)

    2015-08-15

    Fracture of a ceramic liner of a total hip arthroplasty is rare and is radiographically occult if not displaced. We report on two patients in whom ceramic liner fracture was radiographically occult but was diagnosed on subsequent CT scan through appropriate windowing. (orig.)

  16. Clinical–radiologic evaluation of the complications of laparoscopic sleeve gastrectomy: Value of multidetector CT

    Directory of Open Access Journals (Sweden)

    Tamir A. Hassan

    2015-12-01

    Conclusions: As LSG is performed increasingly and frequently, it is essential for radiologists to recognize the normal postoperative anatomy and identify the complications of this procedure. CT is an important imaging tool to diagnose suspected complications of laparoscopic sleeve gastrectomy procedure to ensure accurate diagnosis.

  17. Bilateral internal carotid agenesis: value of CT angiography and correlation to embryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Pilleul, F.; Rouviere, O. [Dept. of Radiology, Hopital Edouard Herriot, Lyon (France); Guibaud, L.; Pracros, J.P. [Dept. of Pediatric Imaging, Hopital Debrousse, Lyon (France); Badinand, N. [Dept. of Pediatric Neurology, Hopital Debrousse, Lyon (France)

    2001-05-01

    Bilateral internal carotid artery agenesis is an uncommon disease, difficult to differentiate from bilateral carotid artery thrombosis. A few case reports have described the contribution of conventional angiogram to make the diagnosis and recognize the anatomic details of this rare malformation. Advantages of CT angiography as a non-invasive radiologic tool are discussed in this case report. (orig.)

  18. The Impact of Transient Hepatic Attenuation Differences in the Diagnosis of Pseudoaneurysm and Arteriovenous Fistula on Follow-Up CT Scans after Blunt Liver Trauma

    Directory of Open Access Journals (Sweden)

    Andreas Hjelm Brandt

    2014-09-01

    Full Text Available A feared complication to liver trauma is delayed vascular complication, such as pseudoaneurysm and arteriovenous fistula (PS/AF seen as focal enhancement on contrast-enhanced computed tomography (CT in the arterial phase. A hyperdense area termed transient hepatic attenuation difference (THAD representing altered hepatic blood flow can be seen in the arterial phase near the liver lesion. The objective of this study was to describe THAD and PS/AF on follow-up CT after blunt liver trauma, and to evaluate if THAD influenced the evaluation of PS/AF. Three radiology residents retrospectively evaluated scans of 78 patients. The gold standard for PS/AF was an evaluation by an experienced senior radiologist, while THAD was a consensus between the residents. PS/AF was present in 14% and THAD in 54%. THAD was located in the periphery of the lesion with hazy borders and mean HU levels of 100, while PS/AF was located within the lesion with focal enhancement and mean HU levels of 170 (p < 0.05. In evaluation of PS/AF, the likelihood of agreement between the observers and the gold standard was 89% when THAD was present, and 98% when THAD was absent (p = 0.04. THAD is common and can hamper the evaluation of PS/AF.

  19. The value of PET, CT and in-line PET/CT in patients with gastrointestinal stromal tumours: long-term outcome of treatment with imatinib mesylate

    Energy Technology Data Exchange (ETDEWEB)

    Goerres, G.W.; Hany, T.F.; Schulthess, G.K. von [University Hospital Zurich, Division of Nuclear Medicine, Zurich (Switzerland); Stupp, R.; Luthi, F.; Leyvraz, S. [University of Lausanne Medical Centre, Multidisciplinary Oncology Centre, Lausanne (Switzerland); Barghouth, G.; Schnyder, P. [University of Lausanne Medical Centre, Department of Radiology, Lausanne (Switzerland); Pestalozzi, B. [University Hospital Zurich, Department of Oncology, Zurich (Switzerland); Dizendorf, E. [University Hospital Zurich, Division of Nuclear Medicine, Zurich (Switzerland); International Tomography Center, Novosibirsk (Russian Federation)

    2005-02-01

    Gastrointestinal stromal tumours (GIST) are mesenchymal neoplasms of the gastrointestinal tract that are unresponsive to standard sarcoma chemotherapy. Imaging of GIST patients is done with structural and functional methods such as contrast-enhanced helical computed tomography (ceCT) and positron emission tomography (PET) with {sup 18}F-fluorodeoxyglucose (FDG). The aim of this study was to compare the prognostic power of PET and ceCT and to evaluate the clinical role of PET/CT imaging. All patients with GIST undergoing PET or PET/CT examinations were prospectively included in this study, and the median overall survival, time to progression and treatment duration were documented. The prognostic significance of PET and ceCT criteria of treatment response was assessed and PET/CT was compared with PET and ceCT imaging. Data for 34 patients (19 male, 15 female, 21-76 years) undergoing PET or PET/CT for staging or restaging were analysed. In 28 patients, PET/CT and ceCT were available after introduction of treatment with the tyrosine kinase inhibitor imatinib mesylate (Gleevec; Novartis, Basel, Switzerland). Patients without FDG uptake after the start of treatment had a better prognosis than patients with residual activity. In contrast, ceCT criteria provided insufficient prognostic power. However, more lesions were found on ceCT images than on PET images, and FDG uptake was sometimes very variable. PET/CT delineated active lesions better than did the combination of PET and ceCT imaging. Both PET and PET/CT provide important prognostic information and have an impact on clinical decision-making in GIST patients. PET/CT precisely delineates lesions and thus allows for the correct planning of surgical interventions. (orig.)

  20. High quality high spatial resolution functional classification in low dose dynamic CT perfusion using singular value decomposition (SVD) and k-means clustering

    Science.gov (United States)

    Pisana, Francesco; Henzler, Thomas; Schönberg, Stefan; Klotz, Ernst; Schmidt, Bernhard; Kachelrieß, Marc

    2017-03-01

    Dynamic CT perfusion acquisitions are intrinsically high-dose examinations, due to repeated scanning. To keep radiation dose under control, relatively noisy images are acquired. Noise is then further enhanced during the extraction of functional parameters from the post-processing of the time attenuation curves of the voxels (TACs) and normally some smoothing filter needs to be employed to better visualize any perfusion abnormality, but sacrificing spatial resolution. In this study we propose a new method to detect perfusion abnormalities keeping both high spatial resolution and high CNR. To do this we first perform the singular value decomposition (SVD) of the original noisy spatial temporal data matrix to extract basis functions of the TACs. Then we iteratively cluster the voxels based on a smoothed version of the three most significant singular vectors. Finally, we create high spatial resolution 3D volumes where to each voxel is assigned a distance from the centroid of each cluster, showing how functionally similar each voxel is compared to the others. The method was tested on three noisy clinical datasets: one brain perfusion case with an occlusion in the left internal carotid, one healthy brain perfusion case, and one liver case with an enhancing lesion. Our method successfully detected all perfusion abnormalities with higher spatial precision when compared to the functional maps obtained with a commercially available software. We conclude this method might be employed to have a rapid qualitative indication of functional abnormalities in low dose dynamic CT perfusion datasets. The method seems to be very robust with respect to both spatial and temporal noise and does not require any special a priori assumption. While being more robust respect to noise and with higher spatial resolution and CNR when compared to the functional maps, our method is not quantitative and a potential usage in clinical routine could be as a second reader to assist in the maps

  1. The prognostic value of brain CT scan in infants with periventricular leukomalacia

    Energy Technology Data Exchange (ETDEWEB)

    Okumura, Akihisa; Hayakawa, Fumio; Kuno, Kuniyoshi (Anjo Kosei Hospital, Aichi (Japan)); Natsume, Jun; Watanabe, Kazuyoshi

    1994-11-01

    Brain CT scan was performed at 40 weeks of conceptional age in 17 preterm infants with periventricular leukomalacia (PVL). The finding of periventricular low density was not useful in differentiating patients with PVL from normal infants, because this finding was seen in 40% of normal infants. The following findings were characteristic of PVL : (1) a marked low density area in centrum semioval, (2) an irregular outline of ventricular wall, and (3) low density spots in periventricular white matter. The findings of ventricular dilation with irregular wall and marked low density area in centrum semioval were correlated with a finding of volume loss on MRI during late infancy and the severity of neurological impairment, especially in severely affected patients. Marked low density area in centrum semioval was characteristic of severe PVL as demonstrated on brain CT scan. (author).

  2. CT Diagnosis of Fitz-Hugh and Curtis Syndrome: Value of the Arterial Phase Scan

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Seung Ho; Kim, Myeong Jin; Lim, Joon Seok; Kim, Joo Hee; Kim, Ki Whang [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2007-02-15

    We wanted to evaluate the role of the arterial phase (AP) together with the portal venous phase (PP) scans in the diagnosis of Fitz-Hugh-Curtis syndrome (FHCS) with using computed tomography (CT). Twenty-five patients with FHCS and 25 women presenting with non-specifically diagnosed acute abdominal pain and who underwent biphasic CT examinations were evaluated. The AP scan included the upper abdomen, and the PP scan included the whole abdomen. Two radiologists blindly and retrospectively reviewed the PP scans first and then they reviewed the AP plus PP scans. The diagnostic accuracy of FHCS on each image set was compared for each reader by analyzing the area under the receiver operating characteristic curve (Az). Weighted kappa (wk) statistics were used to measure the interobserver agreement for the presence of CT signs of the pelvic inflammatory disease (PID) on the PP images and FHCS as the diagnosis based on the increased perihepatic enhancement on both sets of images. The individual diagnostic accuracy of FHCS was higher on the biphasic images (Az = 0.905 and 0.942 for reader 1 and 2, respectively) than on the PP images alone (Az = 0.806 and 0.706, respectively). The interobserver agreement for the presence of PID on the PP images was moderate (wk = 0.530). The interobserver agreement for FHCS as the diagnosis was moderate on only the PP images (wk = 0.413), but it was substantial on the biphasic images (wk 0.719). Inclusion of the AP scan is helpful to depict the increased perihepatic enhancement, and it improves the diagnostic accuracy of FHCS on CT.

  3. The value of {sup 18}F-FDG PET/CT in the assessment of active idiopathic retroperitoneal fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Moroni, Gabriella; Longhi, Selena; Messa, Piergiorgio [Fondazione IRCCS Ca Granda Ospedale Maggiore Policlinico, Division of Nephrology, Milan (Italy); Castellani, Massimo; Martinelli, Isabella; Gerundini, Paolo [Fondazione IRCCS Ca Granda Ospedale Maggiore Policlinico, Department of Nuclear Medicine, Milan (Italy); Balzani, Aurora; Bonelli, Nicola [Fondazione IRCCS Ca Granda Ospedale Maggiore Policlinico, Department of Radiology, Milan (Italy); Dore, Roberto [University of Pavia, Institute of Radiology, IRCCS Foundation, San Matteo Medical Center, Pavia (Italy)

    2012-10-15

    The different stages in idiopathic retroperitoneal fibrosis (IRF) are generally assessed by assay of inflammatory markers and analysis of contrast-enhanced CT images of the retroperitoneal mass. We investigated the potential role of {sup 18}F-FDG PET/CT in this clinical setting. {sup 18}F-FDG uptake was assessed visually and semiquantitatively (using maximum standardized uptake values, SUVmax) in images of the abdominal mass in 22 patients prospectively enrolled from June 2008 to December 2010 who underwent a total of 33 PET/CT studies. The accuracy in discriminating active from inactive disease was calculated assuming as reference a biochemical instrumental evaluation of patients with IRF mostly based on the level of inflammatory indices and contrast enhancement (CE) of the mass at the time of each PET study. In particular, the relationship between SUVmax and CE, the latter calculated from the change in radiodensity (Hounsfield units) between the basal and postcontrast venous portal phases, was evaluated on a three-point scale (0 <20 HU, 1 20-30 HU, 2 {>=}30 HU). SUVmax and CE scores were correlated with the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels. The value of PET/CT in assessing the variation of disease activity over time was also investigated by analysing the changes in metabolic volume (MV) of the retroperitoneal lesion between repeat patient studies. PET/CT accurately discriminated (93.9 %) active from inactive disease. Significant agreement (p < 0.01) was observed between visual and semiquantitative analysis of {sup 18}F-FDG uptake, and CE score. A significant correlation (p < 0.01) was found among SUVmax, CRP levels (rho = 0.54) and ESR (rho = 0.55). Corresponding variations in MV and CE score were observed in patients with multiple studies (p < 0.01; rho = 0.68). {sup 18}F-FDG PET/CT may be considered an alternative imaging method for the assessment of different stages of IRF. (orig.)

  4. The value of MRI and CT in the pre-operative diagnosis of lumbar disc herniation

    Energy Technology Data Exchange (ETDEWEB)

    Hirabayashi, Shigeru; Kumano, Kiyoshi; Takahashi, Soichiro; Ishii, Jun (Kanto Rosai Hospital, Kawasaki, Kanagawa (Japan))

    1991-05-01

    A prospective analysis of computed tomography (CT) and magnetic resonance imaging (MRI) scans in 51 patients with lumbar disc herniation was made to determine the height of hernia for operation and, if impossible, the indications of myelography. Among the 51 patients, 40 (78%) received surgery based on these imaging modalities (Group A); and the remaining 11 (22%) underwent myelography for the confirmation of the height of hernia or detailed examination (Group B). Satisfactory or excellent surgical outcome was achieved in 95% in Group A and in 91% in Group B. Twenty seven patients had multiple disc herniation on CT and MRI; in 17 patients surgery was performed for one disc hernia that was radiologically found to compress the spinal nerve root; and in the other 10 hernia-related disc was not determined by either radiological or neurological manifestations. Satisfactory or excellent surgical outcome could, however, be achieved in 26 patients (96%). Myelography should be indicated when there is no neurological radicular sign in the lower extremities, and when there is no radiological evidence of the compressed spinal nerve root in spite of the presence of multiple disc herniation. The height of hernia may be determined when compression of the spinal nerve root is visualized on CT or MRI. (N.K.).

  5. Infectious sacroiliitis: value of computed tomography (CT) and magnetic resonance imaging (MRI)

    Energy Technology Data Exchange (ETDEWEB)

    Le Breton, C. [Dept. of Radiology, Tenon Hospital, 75 Paris (France); Frey, I. [Dept. of Radiology, Tenon Hospital, 75 Paris (France); Carette, M.F. [Dept. of Radiology, Tenon Hospital, 75 Paris (France); Richaud, J. [Dept. of Radiology, Tenon Hospital, 75 Paris (France); Kujas, A. [Dept. of Radiology, Tenon Hospital, 75 Paris (France); Korzec, J. [Dept. of Radiology, Tenon Hospital, 75 Paris (France); Bigot, J.M. [Dept. of Radiology, Tenon Hospital, 75 Paris (France)

    1992-06-01

    Infectious sacroiliitis is an uncommon septic arthritis, the diagnosis of which is difficult to establish. We retrospectively examined 14 cases of septic sacroiliitis, by CT (two of whom also had an MRI examination). The patient population consisted of eight men and six women; 9 were African, 8 had tuberculous sacroiliitis and 6 pyogenic sacroiliitis. All the cases showed a pre-sacroiliac soft tissue swelling with ring-like enhancement following intravenous contrast in eight cases. A gas image was observed at the center of the abcess in two cases. Joint narrowing was found in four patients and widening in eight, associated with an image of bone sequestration in seven. CT gave an etiologic orientation in 8 cases, and facilitated the guidance of bone biopsy. MRI showed low signal T1-weighted images and high signal T2 of the subchondral bone, joint space and soft tissue abcess. We conclude that CT is helpful in the evaluation of infectious sacroiliitis, and that further studies are necessary to evaluate the role of MRI in such pathologic processes. (orig.)

  6. Verification of CTDI and Dlp values for a head tomography reported by the manufacturers of the CT scanners, using a CT dose profiler probe, a head phantom and a piranha electrometer

    Energy Technology Data Exchange (ETDEWEB)

    Castillo C, E.; Garcia F, I. B.; Garcia H, J.; Roman L, S. [Servicios de Salud de Michoacan, Centro Estatal de Atencion Oncologica, Gertrudis Bocanegra No. 300, Col. Cuauhtemoc, 58020 Morelia, Michoacan (Mexico); Salmeron C, O., E-mail: edithcastillocorona@gmail.com [Servicios de Salud de Michoacan, Hospital General Dr. Miguel Silva, Isidro Huarte s/n, Centro Historico, 58000 Morelia, Michoacan (Mexico)

    2015-10-15

    The extensive use of Computed Tomography (CT) and the associated increase in patient dose calls for an accurate dose evaluation technique. The CT contributes up to 70% of the total dose given to patients during X-ray examinations. The rapid advancements in CT technology are placing new demands on the methods and equipment that are used for quality assurance. The wide beam widths found in CT scanners with multiple beam apertures make it impossible to use existing CT ionization chambers to measure the total dose given to the patient. Using a standard 10 cm CT ionization chamber may result in inaccurate measurements due to underestimation of the dose profile for wide beams. The use a CT dose profiler based on solid-state technology and the Piranha electrometer from RTI electronics provides a potential solution to the arising concerns over patient dose. This study intend to evaluate the feasibility and accuracy of CT Dose Index (CTDI) and Dose Length Product (Dlp) values for a head tomography reported by the manufacturers of the CT scanners at each study. (Author)

  7. Added value of lung perfused blood volume images using dual-energy CT for assessment of acute pulmonary embolism

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Munemasa, E-mail: radokada@yamaguchi-u.ac.jp [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Kunihiro, Yoshie [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Nakashima, Yoshiteru [Department of Radiology, Yamaguchi Grand Medical Center, Oosaki 77, Hofu, Yamaguchi 747-8511 (Japan); Nomura, Takafumi [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Kudomi, Shohei; Yonezawa, Teppei [Department of Radiology, Yamaguchi University Hospital, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Suga, Kazuyoshi [Department of Radiology, St. Hills Hospital, Imamurakita 3-7-18, Ube, Yamaguchi 755-0155 (Japan); Matsunaga, Naofumi [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan)

    2015-01-15

    Purpose: To investigate the added value of lung perfused blood volume (LPBV) using dual-energy CT for the evaluation of intrapulmonary clot (IPC) in patients suspected of having acute pulmonary embolism (PE). Materials and methods: Institutional review board approval was obtained for this retrospective study. Eighty-three patients suspected of having PE who underwent CT pulmonary angiography (CTPA) using a dual-energy technique were enrolled in this study. Two radiologists who were blinded retrospectively and independently reviewed CTPA images alone and the combined images with color-coded LPBV over a 4-week interval, and two separate sessions were performed with a one-month interval. Inter- and intraobserver variability and diagnostic accuracy were evaluated for each reviewer with receiver operating characteristic (ROC) curve analysis. Results: Values for inter- and intraobserver agreement, respectively, were better for CTPA combined with LPBV (ICC = 0.847 and 0.937) than CTPA alone (ICC = 0.748 and 0.861). For both readers, diagnostic accuracy (area under the ROC curve [A{sub z}]) were also superior, when CTPA alone (A{sub z} = 0.888 [reader 1] and 0.912 [reader 2]) was compared with that after the combination with LPBV images (A{sub z} = 0.966 [reader 1] and 0.959 [reader 2]) (p < 0.001). However, A{sub z} values of both images might not have significant difference in statistics, because A{sub z} value of CTPA alone was high and 95% confidence intervals overlapped in both images. Conclusion: Addition of dual-energy perfusion CT to CTPA improves detection of peripheral IPCs with better interobserver agreement.

  8. The value of perfusion CT in predicting the short-term response to synchronous radiochemotherapy for cervical squamous cancer

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiang Sheng; Fan, Hong Xia; Zhu, Hong Xian; Song, Yun Long [Air Force General Hospital of People' s Liberation Army, Department of CT, Beijing (China); Zhou, Chun Wu [Chinese Academy of Medical Sciences, Department of Radiology, Cancer Hospital, Beijing (China)

    2012-03-15

    To determine the value of the perfusion parameters in predicting short-term tumour response to synchronous radiochemotherapy for cervical squamous carcinoma. Ninety-three patients with cervical squamous carcinoma later than stage IIB were included in this study. Perfusion CT was performed for all these patients who subsequently received the same synchronous radiochemotherapy. The patients were divided into responders and non-responders according to short-term response to treatment. Baseline perfusion parameters of the two groups were compared. The perfusion parameters that might affect treatment effect were analysed by using a multivariate multi-regression analysis. The responders group had higher baseline permeability-surface area product (PS) and blood volume (BV) values than the non-responders group (P < 0.05). There was no statistical difference in baseline mean transit time (MTT) and blood flow (BF) value between the two groups (P >0.05). At multivariate multi-regression analysis, BV, PS and tumour size were significant factors in the prediction of treatment effect. Small tumours usually had high PS and BV values, and thus had a good treatment response. Perfusion CT can provide some helpful information for the prediction of the short-term effect. Synchronous radiochemotherapy may be more effective in cervical squamous carcinoma with higher baseline PS and BV. (orig.)

  9. (18)F-FDG PET/CT in lung cancer. The added value of quantification.

    Science.gov (United States)

    Lapa, P; Marques, M; Isidoro, J; Barata, F; Costa, G; de Lima, J P

    2017-05-26

    To test a software application for the quantification of metabolic heterogeneity and to evaluate its superiority in relation to visual interpretation. To investigate if a quantitative analysis adds information to the interpretation of (18)F-FDG-PET/CT. The study analyzed 215 patients with a (18)F-FDG-PET/CT done for the initial staging of lung cancer between March 2011 and December 2015. The study included 57 (26.5%) women and 158 (73.5%) men, with ages ranging from 34 to 88 years (mean±SD: 67.23±10.04). There were 82 surgical stages (I, II, IIIA), and 133 non-surgical stages (IIIB, IV). The primary tumour was analyzed quantitatively by obtaining the following parameters: SUVmax, metabolic active tumour volume (MATV), total lesion glycolysis (TLG), and the entropy heterogeneity index (ET). Heterogeneity was assessed visually. Death dates and/or the follow-up time were registered, ranging from 0.70 to 67.60 months (mean±SD: 23.20±17.68). In multivariate analysis, ET emerged as a better predictor of survival than visual analysis of heterogeneity that was not statistically significant. The C-index determination demonstrated that all quantitative parameters were statistically-significant predictors of survival. Cut-offs were obtained in order to compare survival times. A multivariate analysis was performed. In the total population, the best predictor was the TNM stage, but MATV, ET, and male gender were statistically significant and independent predictors of survival. In stages without surgical indication, the best predictor was the TNM stage, but the MATV and male gender were statistically significant and independent predictors of survival. In the surgical stages, ET was the only statistically significant and independent predictor of survival. Quantification adds prognostic information to the visual analysis of (18)F-FDG-PET/CT. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  10. CT -guided sclerotherapy for simple renal cysts: Value of ethanol concentration monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jin Hong; Du, Yong; Li, Yang; Yang, Han Feng; Xu, Xiao Xue; Zheng, Hou Jun [The Affiliated Hospital of North Sichuan Medical College, Nanchong (China)

    2014-02-15

    The aim of our study was to evaluate the differences between sclerotherapy with and without ethanol concentration monitoring for the treatment of simple renal cysts. Sixty-seven patients with 70 simple renal cysts were randomly assigned to two groups in a 12-month prospective controlled trial. One group (group A) was treated with computed tomography (CT)-guided sclerotherapy without ethanol concentration monitoring (33 patients with 35 cysts), whereas the other group (group B) had ethanol concentration monitoring (34 patients with 35 cysts) during the procedure. Treatment outcomes between the two groups were compared 12 months later with follow-up ultrasound examination. After the 12-month follow-up period, the overall success rate was 74.3% in group A and 94.3% in group B (p = 0.022). The mean cyst size before and after treatment was 8.6 ± 2.0 cm and 2.3 ± 2.9 cm, respectively, in group A, and 8.4 ± 1.7 cm and 0.8 ± 1.9 cm, respectively, in group B. The final size of the cysts in group B was significantly smaller than that in group A (p = 0.015). The likelihood of treatment with ethanol concentration monitoring being successful was approximately 16 times higher than without ethanol concentration monitoring (p = 0.026; odds ratio = 15.7; 95% confidence interval: 1.38-179.49). There were no major complications in either group. Monitoring of Hounsfield units (HU) of ethanol by CT is an effective method in the treatment of simple renal cysts with ethanol sclerotherapy. The ethanol sclerotherapy procedure can be terminated at the point of clear fluid aspiration because the HU (-190) of CT scan corresponds to it.

  11. Value of CT pulmonary arteriography and venography in the evaluation of venous thromboembolism in a multiracial Asian population

    Institute of Scientific and Technical Information of China (English)

    Yeong Ji Lee; Rozman Zakaria; Zaleha Abdul Manaf; Zahiah Mohamed; Yeong Yeh Lee

    2013-01-01

    Background There is increasing evidence that CT pulmonary arteriography and venography allow a better diagnostic yield for deep vein thrombosis (DVT) in suspected acute pulmonary embolism (PE).The aim was to investigate the value for using such an approach in a multiracial Asian population.Methods A total of 135 consecutive subjects with clinically suspected PE in various clinical settings (postoperative in 23 subjects) were referred and evaluated for venous thromboembolism using CT pulmonary arteriography and venography in a tertiary hospital,Malaysia.The distribution of DVT was assessed based on the frequency rate of thrombosis in a particular anatomical region (inferior vena cava,pelvic,femoral and popliteal).Results In 130 subjects,excluding 5 subjects having poor images,both DVT and PE were detected in 11.5% (15/130) subjects and DVT alone was detected in 6.9% (9/130) subjects giving a combined rate of venous thromboembolism of 18.4%.A history of malignancy was significantly associated with positive scans,P=0.02.It was found that left pelvic veins (18.2%) and left femoral veins (19.5%) were more commonly thrombosed in this population.Conclusion CT pulmonary arteriography and venography is a useful technique in the evaluation of venous thromboembolism in a multi-racial Asian population.

  12. Preoperative [{sup 18}F]FDG PET/CT maximum standardized uptake value predicts recurrence of uterine cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hyun Hoon; Kim, Jae Weon; Park, Noh-Hyun; Song, Yong-Sang; Kang, Soon-Beom [Seoul National University College of Medicine, Department of Obstetrics and Gynecology, Cancer Research Institute, Seoul (Korea); Nam, Byung-Ho [National Cancer Center, Division of Cancer Epidemiology and Management, Research Institute, Seoul (Korea); Kang, Keon Wook; Chung, June-Key [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea)

    2010-08-15

    To determine if preoperative [{sup 18}F]FDG-PET/CT imaging has prognostic significance in patients with uterine cervical cancer. Patients with FIGO stage IB to IIA cervical cancer were imaged with integrated FDG PET/CT before radical surgery. The relationship between the maximum standardized uptake value (SUV{sub max}) of FDG in the primary tumour during PET/CT and recurrence was examined. Included in the study were 75 patients. Medical records including clinical data, treatment modalities, and treatment results were retrospectively reviewed. The median duration of follow-up was 13 months (range 3 to 58 months) after treatment. Median preoperative SUV{sub max} values in the primary tumours were significantly higher in patients with higher FIGO stages (p = 0.0149), pelvic lymph node metastasis (p = 0.0068), parametrial involvement (p = 0.0002), large (>4 cm) tumour size (p = 0.0022), presence of lymphovascular space invasion (p = 0.0055), and deep cervical stromal invasion (p < 0.0001). In univariate analysis, lymph node metastasis, parametrial invasion, presence of lymphovascular space invasion, and preoperative SUV{sub max} (uncategorized values) in the primary tumour were significantly associated with recurrence. However, in multivariate analysis, preoperative SUV{sub max} (p = 0.014, HR 1.178, 95% CI 1.034-1.342), age (p = 0.021, HR 0.87, 95% CI 0.772-0.980), and parametrial involvement (p = 0.040, HR 27.974, 95% CI 1.156-677.043) by primary tumour were significantly associated with recurrence. Preoperative FDG uptake by the primary tumour showed a significant association with recurrence in patients with uterine cervical cancer. (orig.)

  13. Multidetector CT of Locally Invasive Advanced Gastric Cancer: Value of Oblique Coronal Reconstructed Images for the Assessment of Local Invasion

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jin Hee; Kim, Ah Yong; Kim, Hye Jin; Yook, Jeong Hwan; Yu, Eun Sil; Jang, Yoon Jin; Park, Seong Ho; Shin, Yong Moon; Ha, Hyun Kwon [Asan Medical Center, Seoul (Korea, Republic of)

    2010-01-15

    To evaluate the diagnostic value of oblique coronal reconstructed CT images to determine the local invasion of advanced gastric cancer (AGC). Thirty-four consecutive patients, who were suspected to have locally invasive advanced gastric cancer (more than T3 stage) on a preoperative MDCT scan and underwent a diagnostic or curative laparotomy, were enrolled in this study. Two reviewers performed an independent blind review of three series of MDCT images in random order; axial (AXI), conventional coronal (CCI), and oblique coronal (OCI) (parallel to long axis of gastric body and pancreas) images. In assessing the local invasion, the reader's confidence for the local invasion of AGC was graded using a five point scale (1 = definitely negative, 5 = definitely positive: T4). With surgical findings and histopathological proofs as reference standards, the diagnostic performance of the three different plans of CT images was employed for the verification of local invasion of AGC on a preoperative CT scan using the receiver operating characteristic (ROC) method. Agreements between the two reviewers were analyzed using weighted kappa statistics. Results: In 19 out of 34 patients, local invasion was confirmed surgically or histopathologically (13 pancreas invasion, 6 liver invasion, 4 major vascular invasion, 3 colon and mesocolon invasion, and 2 spleen invasion). The diagnostic performance of OCI was superior to AXI or CCI in the local invasion of AGC. The differences in the area under the curve of AXI (0.770 {+-} 0.087, 0.700 {+-} 0.094), CCI (0.884 {+-} 0.058, 0.958 {+-} 0.038), and OCI (0.954 {+-} 0.050, 0.956 {+-} 0.049), were statistically significant for both reviewers. Inter-observer agreement was excellent for OCI ({kappa}= .973), which was greater than CCI (({kappa}= .839), and AXI (({kappa}= .763). On a CT scan, OCI might be a useful imaging technique in evaluating locally invasive advanced gastric cancer.

  14. Value of {sup 11}C-choline PET and PET/CT in patients with suspected prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Scher, Bernhard; Albinger, Wolfram; Tiling, Reinhold; Gildehaus, Franz-Josef; Dresel, Stefan [University of Munich, Department of Nuclear Medicine, Munich (Germany); Seitz, Michael [University of Munich, Department of Urology, Munich (Germany); Scherr, Michael; Becker, Hans-Christoph [University of Munich, Department of Radiology, Munich (Germany); Souvatzogluou, Michael; Wester, Hans-Juergen [Technical University of Munich, Department of Nuclear Medicine, Munich (Germany)

    2007-01-15

    The value and limitations of {sup 11}C-choline PET and PET/CT for the detection of prostate cancer remain controversial. The aim of this study was to investigate the diagnostic efficacy of {sup 11}C-choline PET and PET/CT in a large group of patients with suspected prostate cancer. Fifty-eight patients with clinical suspicion of prostate cancer underwent {sup 11}C-choline PET (25/58, Siemens ECAT Exact HR+) or PET/CT (33/58, Philips Gemini) scanning. On average, 500 MBq of {sup 11}C-choline was administered intravenously. Studies were interpreted by raters blinded to clinical information and other diagnostic procedures. Qualitative image analysis as well as semiquantitative SUV measurement was carried out. The reference standard was histopathological examination of resection specimens or biopsy. Prevalence of prostate cancer in this selected patient population was 63.8% (37/58). {sup 11}C-choline PET and PET/CT showed a sensitivity of 86.5% (32/37) and a specificity of 61.9% (13/21) in the detection of the primary malignancy. With regard to metastatic spread, PET showed a per-patient sensitivity of 81.8% (9/11) and produced no false positive findings. Based on our findings, differentiation between benign prostatic changes, such as benign prostatic hyperplasia or prostatitis, and prostate cancer is feasible in the majority of cases when image interpretation is primarily based on qualitative characteristics. SUV{sub max} may serve as guidance. False positive findings may occur due to an overlap of {sup 11}C-choline uptake between benign and malignant processes. By providing functional information regarding both the primary malignancy and its metastases, {sup 11}C-choline PET may prove to be a useful method for staging prostate cancer. (orig.)

  15. The value of MRI and CT-discography as a basis for surgical decision making

    Energy Technology Data Exchange (ETDEWEB)

    Uchiyama, Toru; Yasukawa, Keiichiro; Mizui, Nobuko; Tamaki, Michio; Takahashi, Eiichi; Saito, Tomoo [Nagaoka Chuo Hospital, Niigata (Japan)

    1995-12-01

    It is important to know the presence/absence of perforation of the posterior longitudinal ligament by herniation before surgery of lumbar disc herniation. MR images and CTD (CT-discography) findings of 25 patients with lumbar disc herniation and the findings at surgery were compared, and the possibility of judging presence/absence of perforation of posterior longitudinal ligament by herniation was retrospectively studied. The cases showing broken black line on MRI and the cases with epidural leak on CT were diagnosed as having perforation of the posterior longitudinal ligament. The diagnosis was made by a radiologist to whom the clinical symptoms of the patients had not been informed, and compared with the findings at surgery. The accuracy was 64.0%, sensitivity 69.2%, and specificity 58.3% on MRI, as for CTD on the other hand, accuracy was 60.0%, sensitivity 54.6%, and specificity 54.6%. The usefulness of black line on MRI and epidural leak on CTD for preoperative diagnosis of the presence/absence of perforation of the posterior longitudinal ligament by herniation was low. (S.Y.).

  16. Diagnostic value of transmural perfusion ratio derived from dynamic CT-based myocardial perfusion imaging for the detection of haemodynamically relevant coronary artery stenosis

    NARCIS (Netherlands)

    A. Coenen (Adriaan); M. Lubbers (Marisa); A. Kurata (Akira); A.K. Kono (Atsushi K.); A. Dedic (Admir); R.G. Chelu (Raluca Gabriela); M.L. Dijkshoorn (Marcel); Rossi, A. (Alexia); R.J.M. van Geuns (Robert Jan); K. Nieman (Koen)

    2016-01-01

    textabstractObjectives: To investigate the additional value of transmural perfusion ratio (TPR) in dynamic CT myocardial perfusion imaging for detection of haemodynamically significant coronary artery disease compared with fractional flow reserve (FFR). Methods: Subjects with suspected or known coro

  17. Comparison of the prognostic values of {sup 68}Ga-DOTANOC PET/CT and {sup 18}F-FDG PET/CT in patients with well-differentiated neuroendocrine tumor

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Punit; Naswa, Niraj; Kc, Sudhir Suman; Yadav, Yashwant; Kumar, Rakesh; Bal, Chandrasekhar [All India Institute of Medical Sciences, Department of Nuclear Medicine, Ansari Nagar, New Delhi (India); Alvarado, Luis Andres; Dwivedi, Alok Kumar [Texas Tech University Health Sciences Center, Division of Biostatistics and Epidemiology, El Paso, TX (United States); Ammini, Ariachery C. [All India Institute of Medical Sciences, Department of Endocrinology and Metabolism, New Delhi (India)

    2014-12-15

    To determine the prognostic value of {sup 68}Ga-DOTANOC PET/CT in patients with well-differentiated neuroendocrine tumor (NET), and to compare the prognostic value with that of {sup 18}F-FDG PET/CT and other conventional clinicopathological prognostic factors. Data from 37 consecutive patients (age 46.6 ± 13.5 years, 51 % men) with well-differentiated NET who underwent {sup 68}Ga-DOTANOC PET/CT and {sup 18}F-FDG PET/CT were analyzed. All patients underwent a baseline visit with laboratory and radiological examinations. Clinical and imaging follow-up was performed in all patients. Progression-free survival (PFS) was measured from the date of the first PET/CT scan to the first documentation of progression of disease. {sup 68}Ga-DOTANOC PET/CT was positive in 37 of the 37 patients and {sup 18}F-FDG PET/CT was positive in 21. During follow-up 10 patients (27 %) showed progression of disease and 27 (73 %) showed no progression (24 stable disease, 3 partial response). The median follow-up was 25 months (range 2 - 52 months). Among the variables evaluated none was significantly different between the progressive disease and nonprogressive disease groups, with only SUVmax on {sup 68}Ga-DOTANOC PET/CT being borderline significant (P = 0.073). In the univariate analysis for PFS outcome, SUVmax on {sup 68}Ga-DOTANOC PET/CT (HR 0.122, 95 % CI 0.019 - 0.779; P = 0.026) and histopathological tumor grade (HR 4.238, 95 % CI 1.058 - 16.976; P = 0.041) were found to be associated with PFS. Other factors including age, sex, primary site, Ki-67 index, TNM stage, {sup 18}F-FDG PET/CT status (positive/negative), SUVmax on {sup 18}F-FDG PET/CT and type of treatment were not significant. In multivariable analysis, only SUVmax on {sup 68}Ga-DOTANOC PET/CT was found to be an independent positive predictor of PFS (HR 0.122, 95 % CI 0.019 - 0.779; P = 0.026). SUVmax measured on {sup 68}Ga-DOTANOC PET/CT is an independent, positive prognostic factor in patients with well-differentiated NET and

  18. Xenon ventilation CT using dual-source and dual-energy technique in children with bronchiolitis obliterans: correlation of xenon and CT density values with pulmonary function test results

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo; Yang, Dong Hyun; Seo, Joon Beom; Chae, Eun Jin; Lee, Jeongjin [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Songpa-gu, Seoul (Korea); Hong, Soo-Jong; Yu, Jinho; Kim, Byoung-Ju [University of Ulsan College of Medicine, Department of Pediatrics, Asan Medical Center, Seoul (Korea); Krauss, Bernhard [Siemens Medical Solutions AG-Computed Tomography, Forchheim (Germany)

    2010-09-15

    Xenon ventilation CT using dual-source and dual-energy technique is a recently introduced, promising functional lung imaging method. To expand its clinical applications evidence of additional diagnostic value of xenon ventilation CT over conventional chest CT is required. To evaluate the usefulness of xenon ventilation CT using dual-source and dual-energy technique in children with bronchiolitis obliterans (BO). Seventeen children (age 7-18 years; 11 boys) with BO underwent xenon ventilation CT using dual-source and dual-energy technique. Xenon and CT density values were measured in normal and hyperlucent lung regions on CT and were compared between the two regions. Volumes of hyperlucent regions and ventilation defects were calculated with thresholds determined by visual and histogram-based analysis. Indexed volumes of hyperlucent lung regions and ventilation defects were correlated with pulmonary function test results. Effective doses of xenon CT were calculated. Xenon (14.6 {+-} 6.4 HU vs 26.1 {+-} 6.5 HU; P < 0.001) and CT density (-892.8 {+-} 25.4 HU vs -812.3 {+-} 38.7 HU; P < 0.001) values were significantly lower in hyperlucent regions than in normal lung regions. Xenon and CT density values showed significant positive correlation for the entire lung in 16 children ({gamma} = 0.55 {+-} 0.17, P < 0.001 or =0.017) and for hyperlucent regions in 13 children ({gamma} = 0.44 {+-} 0.16, P < 0.001 or =0.001-0.019). Indexed volumes and volume percentages of hyperlucent lung regions and ventilation defects showed strong negative correlations with forced expiratory volume [FEV1, ({gamma} = -0.64-0.85, P {<=} 0.006)], FEV1/forced vital capacity [FVC, ({gamma} = -0.63-0.84, P {<=} 0.008)], and forced midexpiratory flow rate [FEF{sub 25-75}, ({gamma} = -0.68-0.88, P {<=} 0.002). Volume percentages of xenon ventilation defects (35.0 {+-} 16.4%)] were not significantly different from those of hyperlucent lung regions (38.2 {+-} 18.6%). However, mismatches between the

  19. Evaluation of stenosis severity of coronary calcified lesions using transluminal attenuation gradient: clinical application of 320-row volume CT.

    Science.gov (United States)

    Yang, Fengfeng; Dong, Jie; Wang, Wei; Wang, Xiuting; Fu, Xiaojiao; Kumar, Nanda C; Zhang, Tong

    2017-08-01

    The aim of this study was to evaluate the accuracy of transluminal attenuation gradient (TAG) in diagnosing the stenosis degree of difficult lesions to accurately assess the degree of luminal stenosis using coronary computed tomography angiography (CCTA). A total of 130 patients consecutively received CCTA and coronary angiography (CAG). The average transluminal Hounsfield units (HU) of the regions of interest were consecutively measured at an interval of 5 mm from the ostium to the distal level, followed by the calculation of TAG. The diagnostic performance of CCTA, TAG and CCTA+TAG for the stenosis degree of coronary calcified lesions and their reclassification for stenosis degree were analyzed, especially for calcified lesions. Compared with CAG, the TAG in CCTA was consistent with the largest stenosis degree of each blood vessel. TAG improved the accuracy of CCTA in the diagnosis of calcified lesions (Pcoronary calcified lesions were 90.26%, 95.45%, 98.58% and 73.68%. TAG for calcified lesions had moderate sensitivity (86.61%; 95% CI: 81.8-90.5%) and high specificity (91.20%; 95% CI: 84.8-95.5%). In addition, TAG can help to improve the reclassification of CCTA for coronary stenosis degree, especially for calcified lesions (NRI=0.127, P=0.045). TAG can help to improve the diagnostic performance of CCTA for the stenosis degree of lesions, and it may also help to improve the reclassification of the stenosis degree of calcified lesions.

  20. PET/CT Artifacts

    OpenAIRE

    Blodgett, Todd M.; Mehta, Ajeet S.; Mehta, Amar S.; Laymon, Charles M; Carney, Jonathan; Townsend, David W.

    2011-01-01

    There are several artifacts encountered in PET/CT imaging, including attenuation correction (AC) artifacts associated with using CT for attenuation correction. Several artifacts can mimic a 2-deoxy-2-[18F] fluoro-D-glucose (FDG) avid malignant lesions and therefore recognition of these artifacts is clinically relevant. Our goal was to identify and characterize these artifacts and also discuss some protocol variables that may affect image quality in PET/CT.

  1. Combined {sup 18}F-FDG-PET/CT imaging of the head and neck. An approach to metal artifact correction

    Energy Technology Data Exchange (ETDEWEB)

    Schaefers, K.P. [Univ. Hospital Muenster (Germany). Dept. of Nuclear Medicine; Raupach, R. [Univ. Hospital Essen (Germany); Beyer, T. [Siemens Medical Solutions, Computed Tomography, Forchheim (Germany); Timaq medical imaging Inc, Zuerich (Switzerland)

    2006-07-01

    PET/CT imaging is particularly promising for head/neck malignancies, but dental implants lead to biased CT attenuation and PET activity values following CT-based attenuation correction (CT-AC). Objective: Here, we implement a metal artifact correction procedure (MAR) as part of the CT-AC for PET/CT imaging. Results: Phantom studies indicate a maximum quantitative bias in CT and PET of 1000 HU and 30%, which is reduced to 230 HU and 6%, respectively following MAR. These results were verified in selected patients. Conclusion: Artifacts and biases from dental implants can be reduced in PET/CT imaging by applying a simple MAR as part of the CT-AC. (orig.)

  2. The Diagnostic Value of 18F-FDG PET/CT in Association with Serum Tumor Marker Assays in Breast Cancer Recurrence and Metastasis

    Directory of Open Access Journals (Sweden)

    Ying Dong

    2015-01-01

    Full Text Available Background. After initial treatment of breast cancer (BC, monitoring locoregional recurrence and distant metastases is a great clinical challenge. Objective. To evaluate the efficacy of PET/CT in association with serum tumor makers in BC follow-up. Methods. Twenty-six women with a history of modified radical mastectomy were evaluated by 18F-FDG PET/CT. The results of PET/CT were compared with those of conventional imaging techniques (CITs (including mammography, chest radiography, CT, MRI, ultrasound, and bone scintigraphy. Serum tumor markers of CEA, CA 125, and CA 15-3 in the BC patients were also analyzed in association with the results of PET/CT. Results. Compared with CITs, PET/CT was more sensitive to detect the malignant foci and had better patient-based sensitivity and specificity. The mean CA 15-3 serum level was significantly higher in the confirmed positive patients of PET/CT results than in the confirmed negative ones, while there were no significant differences in the serum levels of CEA and CA 125 of both groups. Conclusion. PET/CT is a highly efficient tool for BC follow-up compared with CITs. The high serum levels of CA 15-3 in confirmed positive PET/CT patients indicated the clinical value of CA 15-3 in BC follow-up.

  3. Clinical value of {sup 18}F-fluorodihydroxyphenylalanine positron emission tomography/computed tomography ({sup 18}F-DOPA PET/CT) for detecting pheochromocytoma

    Energy Technology Data Exchange (ETDEWEB)

    Luster, Markus; Zeich, Katrin; Glatting, Gerhard; Buck, Andreas K.; Solbach, Christoph; Reske, Sven N. [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); Karges, Wolfram [RWTH Aachen, Division of Endocrinology and Diabetes, Aachen (Germany); Pauls, Sandra [University of Ulm, Department of Radiology, Ulm (Germany); Verburg, Frederik A. [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Dralle, Henning [University Halle-Wittenberg, Department of General, Visceral and Vascular Surgery, Halle (Germany); Neumaier, Bernd [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); Max-Planck-Institut fuer Neurologische Forschung, Section for Radiochemistry, Cologne (Germany); Mottaghy, Felix M. [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); RWTH Aachen, Department of Nuclear Medicine, Aachen (Germany)

    2010-03-15

    In detecting pheochromocytoma (PHEO), positron emission tomography (PET) with the radiolabelled amine precursor {sup 18}F-fluorodihydroxyphenylalanine ({sup 18}F-DOPA) offers excellent specificity, while computed tomography (CT) provides high sensitivity and ability to localize lesions; therefore, the combination of these modalities could be advantageous in this setting. The aim of this study was to investigate whether combined {sup 18}F-DOPA PET/CT more accurately detects and localizes PHEO lesions than does each modality alone. {sup 18}F-DOPA PET, CT and {sup 18}F-DOPA PET/CT images of 25 consecutive patients undergoing diagnostic scanning of suspected sporadic or multiple endocrine neoplasia type 2 syndrome-associated PHEO were reviewed retrospectively in randomized sequence. Two blinded observers scored the images regarding the likelihood of PHEO being present and localizable. Results were correlated with subsequent clinical history and, when available, histology. Of the 19 lesions detected by all three modalities, PET identified each as positive for PHEO, but was unable to definitively localize 15 of 19 (79%). CT could definitively localize all 19 lesions, but could not definitively diagnose or exclude PHEO in 18 of 19 (95%) lesions. Furthermore, CT falsely identified as negative for PHEO one lesion which was judged to be positive for this tumor by both PET and PET/CT. Only in PET/CT scans were all 19 lesions accurately characterized and localized. On a per-patient basis, the sensitivity of {sup 18}F-DOPA PET/CT for PHEO was 100% and the specificity 88%, with a 100% positive predictive value and an 88% negative predictive value. {sup 18}F-DOPA PET/CT more accurately diagnoses and localizes adrenal and extra-adrenal masses suspicious for PHEO than do {sup 18}F-DOPA PET or CT alone. (orig.)

  4. Radiological diagnosis of primary sclerosing cholangitis: value of ERC and CT; Radiologische Diagnostik der Primaer Sklerosierenden Cholangitis: Wertigkeit von ERC und CT

    Energy Technology Data Exchange (ETDEWEB)

    Kollmann, F.D. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Maeurer, J. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Hintze, R.E. [Chirurgische Klinik, Klinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Adler, A. [Klinik fuer Innere Medizin mit Schwerpunkt Gastroenterologie, Klinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Veltzke, W. [Klinik fuer Innere Medizin mit Schwerpunkt Gastroenterologie, Klinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Lohmann, R. [Chirurgische Klinik, Klinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Felix, R. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

    1994-12-31

    To evaluate the use of computed tomography (CT) in primary sclerosing cholangitis (PSC) as compared to endoscopic-retrograde cholangiography (ERC), imaging studies of 24 patients were reviewed. 19 patients were studied by ERC, 19 by CT and 14 by both. In 17 cases, ERC confirmed PSC. One cholangiogram suggested a tumor. CT reflected PSC in only 11 cases, while three patients displayed a mass lesion. Thus, ERC remains the standard imaging technique for diagnosing PSC, whereas CT proves beneficial in excluding hepatic masses. (orig.) [Deutsch] Um den Stellenwert der endoskopisch-retrograden Cholangiographie (ERC) bei Primaer Sklerosierender Cholangitis (PSC) mit dem der Computertomographie (CT) zu vergleichen, wurden Untersuchungen von 24 Patienten mit der klinischen Verdachtsdiagnose PSC retrospektiv ausgewertet. 19 Patienten wurden mit ERC untersucht, 19 mit CT und 14 mit beiden Verfahren. Durch ERC konnte in 17 Faellen die Diagnose bestaetigt werden. In einem Patienten fand sich eine tumorverdaechtige Laesion. Im CT konnten nur in elf Faellen Gallengangsveraenderungen nachgewiesen werden, in drei Untersuchungen jedoch hepatische Raumforderungen. Die ERC bleibt damit die aussagekraeftigere Untersuchung zur Bestaetigung einer PSC-Verdachtsdiagnose, waehrend CT vor allem zur Tumordiagnostik bei PSC-Patienten indiziert ist. (orig.)

  5. The relationship between developmental lumbar spinal stenosis and its BMD value : comparison by single energy quantitative CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hak Jin; Kim, Kun Il; Song, Keun Sung [Pusan National Univ. Hospital, Pusan (Korea, Republic of)

    1996-03-01

    The purpose of this study is to evaluate the relationship between developmental lumbar spinal stenosis and its BMD value by using the single energy quantitative CT(SEQCT). Eighty normal volunteers(20-60years) were selected as a control group and 28 patients with developmental lumbar spinal stenosis were selected as a disease group. The two groups were divided into a younger (20-39 years) and an older subgroup (40-60 years), and were further divided into male and female subgroups. All the cases showed no evidence of metabolic disease, fracture, herniated nucleus pulposus, degererative spondylosis, infectious disease, tumors or had no history of absolute immobilization of more than two weeks. All underwent lumbar spine CT and SEQCT. we measured bone mineral density(BMD) at the cancellous bone of L1, 2, 3 and obtained the mean and its one standard deviation, and compared the data between each sub-group of the control and the disease group using ANOVA. There was a significant low BMD value in the younger male patient subgroup compared with the control subgroup(p<0.005). Developmental lumbar spinal stenosis in a young male may be a factor of decreasing BMD of the body of the spine.

  6. Value of MR and CT Imaging for Assessment of Internal Carotid Artery Encasement in Head and Neck Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    W. L. Lodder

    2013-01-01

    Full Text Available Objective. This study was conducted to assess the value of CT and MR imaging in the preoperative evaluation of ICA encasement. Methods. Based upon three patient groups this study was performed. Retrospective analysis of 260 neck dissection reports from 2001 to 2010 was performed to determine unexpected peroperative-diagnosed encasement. Two experienced head and neck radiologists reviewed 12 scans for encasement. Results. In four out of 260 (1.5% patients undergoing neck dissection, preoperative imaging was false negative as there was peroperative encasement of the ICA. Of 380 patients undergoing preoperative imaging, the radiologist reported encasement of the ICA in 25 cases. In 342 cases no encasement was described, 125 of these underwent neck dissection, and 2 had encasement peroperatively. The interobserver variation kappa varied from 0.273 to 1 for the different characteristics studied. Conclusion. These retrospectively studied cohorts demonstrate that preoperative assessment of encasement of the ICA using MRI and/or CT was of value in evaluation of ICA encasement and therefore contributively in selecting operable patients (without ICA encasement, since in only 1.5% encasement was missed. However, observer variation affects the reliability of this feature.

  7. Structure-oriented singular value decomposition for random noise attenuation of seismic data

    Science.gov (United States)

    Gan, Shuwei; Chen, Yangkang; Zu, Shaohuan; Qu, Shan; Zhong, Wei

    2015-04-01

    Singular value decomposition (SVD) can be used both globally and locally to remove random noise in order to improve the signal-to-noise ratio (SNR) of seismic data. However, it can only be applied to seismic data with simple structure such that there is only one dip component in each processing window. We introduce a novel denoising approach that utilizes a structure-oriented SVD, and this approach can enhance seismic reflections with continuous slopes. We create a third dimension for a 2D seismic profile by using the plane-wave prediction operator to predict each trace from its neighbour traces and apply SVD along this dimension. The added dimension is equivalent to flattening the seismic reflections within a neighbouring window. The third dimension is then averaged to decrease the dimension. We use two synthetic examples with different complexities and one field data example to demonstrate the performance of the proposed structure-oriented SVD. Compared with global and local SVDs, and f-x deconvolution, the structure-oriented SVD can obtain much clearer reflections and preserve more useful energy.

  8. Multidetector CT Enterography versus Double-Balloon Enteroscopy: Comparison of the Diagnostic Value for Patients with Suspected Small Bowel Diseases

    Directory of Open Access Journals (Sweden)

    Jingjing Wang

    2016-01-01

    Full Text Available Aim. To compare the diagnostic value of multidetector CT enterography (MDCTE and double-balloon enteroscopy (DBE for patients with suspected small bowel diseases. Methods. From January 2009 to January 2014, 190 patients with suspected small bowel diseases were examined with MDCTE and DBE. The characteristics of the patients, detection rates, diagnostic yields, sensitivity, specificity, positive predictive value, and negative predictive value were described and analyzed. Results. The overall detection rates of DBE and MDCTE were 92.6% and 55.8%, respectively (P<0.05, while the overall diagnostic yields were 83.2% and 33.7%, respectively (P<0.05. The sensitivity, specificity, positive predictive value, and negative predictive value of DBE were all higher than those of MDCTE. DBE had a higher diagnostic yield for OGIB (87.3% versus 20.9%, P<0.05. The diagnostic yields of DBE were higher than those of MDCTE for inflammatory diseases, angioma/angiodysplasia, and diverticulums, while being not for gastrointestinal tumors/polyps. Conclusions. The diagnostic value of DBE for small bowel diseases is better than that of MDCTE as a whole, but if gastrointestinal tumors are suspected, MDCTE is also needed to gain a comprehensive and accurate diagnosis.

  9. Value of CT in the diagnosis of ventilator-associated pneumonia; Stellenwert der CT bei der Diagnose der Ventilator-assoziierten Pneumonie

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, U.; Pereira, P.; Laniado, M.; Claussen, C.D. [Tuebingen Univ. (Germany). Abt. fuer Radiologische Diagnostik; Heininger, A. [Tuebingen Univ. (Germany). Klinik fuer Anaesthesiologie

    1999-02-01

    Purpose: To analyse the diagnostic accuracy of computed tomography (CT) in ventilator-associated pneumonia (VAP). Materials and methods: 23 patients on mechanical ventilation with a new pulmonary abnormality on chest X-ray were examined with both spiral-CT and high-resolution CT. The diagnosis VAP was made according to prospectively defined criteria. Bronchoscopic specimen asservation with protected specimen brushing (PSB) served as gold standard. Results: With PSB, 11 of 23 patients were found to have VAP. CT showed a sensitivity and specificity of 53% and 63%, respectively. Ground glass infiltrates appeared to have a 100% specificity but were found in only 5/11 patients. Conclusions: CT is not the method of choice for diagnosing VAP. Groundglass infiltrates seeming to be highly specific are only inconstantly found. (orig.) [Deutsch] Ziel: Der diagnostische Stellenwert der Computertomographie (CT) bei der Ventilator-assoziierten Pneumonie (VAP) sollte prospektiv analysiert werden. Material und Methoden: 23 beatmete Patienten mit neu aufgetretener pneumoniesuspekter Verschattung wurden mittels Spiral-CT und High-Resolution-CT untersucht. Die Diagnose der VAP erfolgte mittels prospektiv definierter Kriterien. Als Goldstandard diente die bronchoskopische Keimgewinnung mittels Protected-Specimen-Brushing (PSB), wobei als Pneumonienachweis ein Schwellenwert von >10{sup 3} colony forming units (cfu)/ml angenommen wurde. Ergebnisse: Bei 11/23 Patienten wurde mittels PSB die Diagnose VAP gestellt. Die CT zeigte eine Sensitivitaet von 53% und ein Spezifitaet von 63%. Milchglasartige Infiltrate zeigten eine Spezifitaet von 100%, wurden jedoch nur bei 5/11 Patienten mit VAP gefunden. Schlussfolgerungen: Die CT ist zur Diagnosefindung VAP nur bedingt geeignet. Milchglasartigen Infiltraten scheint bei der VAP ein hoher diagnostischer Stellenwert zuzukommen, sie werden jedoch nur inkonstant gefunden. (orig.)

  10. 基于肺平均CT值的4D-CT图像重建方法研究%4D-CT reconstruction based on average CT value of the lungs

    Institute of Scientific and Technical Information of China (English)

    张书旭; 余辉; 王锐濠; 张国前; 齐斌; 林生趣

    2014-01-01

    目的 探讨基于肺平均CT值(ACV)在普通CT上实现4D-CT重建的可行性.方法 根据CT值的定义和特性,本研究提出了"肺ACV原理":在呼吸运动过程中,全肺的ACV将随呼吸运动而呈现周期性变化,据此可以确定进行Cine扫描时,肺部各CT图像的呼吸相位.然后,用VC++语言开发了相应ACV 4D-CT重建系统.在自由呼吸状态下对患者进行多床位Cine模式扫描,每个床位持续扫描6 s、共进行12次CT重建.扫描后,分别计算各CT图像中肺的ACV,按床位绘制肺ACV随重建时间变化的曲线,据此确定每层CT图像所处的呼吸相位,按相位对所有CT图像进行排序,可获得多个不同呼吸相位的CT系列,即4D-CT.结果 利用商售RPM系统重建的4D-CT图像,证实了肺ACV原理;据此原理,对多床位Cine模式扫描CT图像进行排序,在普通CT上实现了满意的4D-CT重建.结论 基于肺ACV原理,可实现简便、可靠的4D-CT重建,其重建过程不依赖于体外呼吸监测装置,具有普遍适用性.%Objective To investigate the feasibility of 4D-CT reconstruction based on average CT value(ACV)of the lungs on conventional CT.Methods According to the definition and characteristics of the CT values,a principle of pulmonary ACV was proposed:the ACV of whole lung presents cyclic variation during respiration,which can determine each respiratory phase position in lung CT image during Cine scanning.In this study,5 sets of reconstructed 4D-CT images based on commercial Real-time Position Management(RPM)system were selected to verify the ACV principle.Then,the corresponding ACV-based 4D-CT reconstruction system was developed by VC++language.Patients were scanned by multiple-bed Cine mode under the state of free breathing,with 6 seconds Cine duration for each bed and a total of 12 CT reconstructions.After scanning,the lung ACV in each CT image was calculated respectively,and the curve of lung ACV over the reconstruction time was drawn for each bed to

  11. CT脑灌注成像临床诊断急性脑梗死价值评价与平扫CT值差值的测量价值%Value Evaluation on Clinical Diagnosis of CT Cerebral Perfusion Imaging on Acute Cerebral infarction and Measurement Value of Difference Value of Plain Scan CT Value

    Institute of Scientific and Technical Information of China (English)

    余东

    2015-01-01

    Objective This Paper is to explore the application value of CT perfusion imaging and differential value of measured CT value in the diagnosis of acute cerebral infarction. Methods Thirty six patients with acute cerebral infarction admitted the Radiology Department of the Hospital were selected as research subjects, retrospective analysis and summary were conducted according to clinical data. CT plaint scan and brain CT perfusion imaging were made respectively, The time to peak (TIP), cerebral blood flow (CBF) and cerebral blood volume (CBV) of CT perfusion imaging were evaluated, the difference of CT value on both sides of symmetric positions was measured. In addition, 36 patients with no brain disease and normal nervous function were divided into the control group, and diagnostic value of the difference between CT perfusion imaging and CT measurement value in acute cerebral infarction was analyzed. Results It is visually found that there were 17 patients with suspicious lesions with the sensitivity at 47.2%, and it was found that there were 28 patients with suspicious lesions by measuring CT value difference. It was found that the CTP of 3 patients was normal CT perfusion imaging examination, and such 2 patients were finally diagnosed to suffer from transient ischemic attack, and others were abnomal, rCBF, rCBV and rTTP changed obviously, the comparison in lesion center and perimeter and controlled side satisfied p<0.05, and the differences were statistically significant. Conclusion CT perfusion imaging and the difference value in CT value measurement delivers high application value in the diagnosis of acute cerebral infarction, and it is capable of diagnosing cerebral infarction in early differential diagnosis, the infarct area and ischemic penumbra area may be differentiated via through quantitative analysis, providing important basis for clinical determination on the existence of infarct and development of therapeutic schedule.%目的:探讨CT灌注成像

  12. [Chest high resolution CT features of extrinsic allergic alveolitis and its diagnostic value].

    Science.gov (United States)

    Ban, Cheng-jun; Dai, Hua-ping; Zhang, Shu; Zhang, Lei; Ye, Qiao; Zhu, Min

    2010-04-27

    To summarize the chest high-resolution CT (HRCT) features of the patients with extrinsic allergic alveolitis (EAA). We analyzed the images of chest HRCT of 34 patients diagnosed as EAA at our hospital from February 2001 to August 2009. All patients had a history of environmental exposure. The duration of intermittent or continuous antigen exposure was from 3 months to 13 years. Two patients showed acute clinical manifestations. There were 22 sub-acute and 10 chronic cases. Acute EAA was characterized by ground-glass opacities, air trapping and/or mosaic sign on HRCT. The HRCT features of subacute EAA included patchy ground-glass opacities with mosaic sign (n = 11, 50.0%) and diffusely distributed centrilobular nodules (n = 7, 31.8%) with mosaic sign (n = 4, 18.2%). All patients with chronic EAA had reticular and honeycombing lesions on HRCT. There were 3 cases with ground-glass opacities, 3 with mosaic sign, and 3 with centrilobular nodules. The typical findings of chest HRCT are helpful for making a diagnosis and differential diagnosis of EAA.

  13. Value of ¹⁸F-FDG PET-CT in surveillance of postoperative colorectal cancer patients with various carcinoembryonic antigen concentrations.

    Science.gov (United States)

    Zhang, Yan; Feng, Bin; Zhang, Guo-Li; Hu, Man; Fu, Zheng; Zhao, Fen; Zhang, Xiao-Li; Kong, Li; Yu, Jin-Ming

    2014-06-07

    To evaluate the value of positron emission tomography (PET)/computerized tomography (CT) in surveillance of colorectal cancer (CRC) patients with different carcinoembryonic antigen (CEA) concentrations. One hundred and six postoperative CRC patients who had suspected recurrence or metastasis and received fluorodeoxyglucose (FDG) PET/CT within one week were included in this study. The final diagnosis was confirmed by histological examination or clinical follow-up over at least six months. The sensitivity, specificity, and accuracy of FDG PET/CT were 95.2%, 82.6%, and 92.5%, and 94.8%, 81.4% and 92.8%, respectively, in the case- and lesion-based analyses. The sensitivity and accuracy of FDG PET/CT significantly differed from CT in both analyses (χ(2) = 8.186, P = 0.004; χ(2) =6.201, P = 0.013; χ(2) =13.445, P = 0.000; χ(2) =11.194, P = 0.001). In the lesion-based analysis, the sensitivity, specificity, and accuracy of FDG PET/CT in the abnormal CEA group were 97.8%, 82.6%, and 95.6%, compared with 81.3%, 80%, and 80.6% for patients with normal CEA levels. In case-based analysis, the sensitivity, specificity, and accuracy of FDG PET/CT were 97.2%, 77.8%, and 95% in abnormal CEA group. Only in lesion-based analysis, the sensitivity and accuracy of FDG PET/CT in the abnormal CEA group were significantly superior to those in the normal CEA group (χ(2) =6.432, P = 0.011; χ(2) =7.837, P = 0.005). FDG PET/CT changed the management in 45.8% of patients with positive scans. FDG PET/CT showed superior diagnostic value and is an advisable option in surveillance of postoperative CRC patients with a vague diagnosis.

  14. Value of CT angiography in anterior circulation large vessel occlusive stroke: Imaging findings, pearls, and pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Power, Sarah, E-mail: drsarahpower@gmail.com [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); McEvoy, Sinead H., E-mail: sineadmcevoy@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Cunningham, Jane, E-mail: janecunningham0708@gmail.com [Department of Radiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Ti, Joanna P., E-mail: joannapearlyti@gmail.com [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Looby, Seamus, E-mail: seamuslooby@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); O' Hare, Alan, E-mail: alanohare@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Williams, David, E-mail: davidwilliams@rcsi.ie [Department of Geriatrics and Stroke Medicine, Royal College of Surgeons in Ireland (RCSI) and Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Brennan, Paul, E-mail: paulbrennan@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Thornton, John, E-mail: johnthornton@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland)

    2015-07-15

    Highlights: • Site of occlusion determines potential collateralization routes and impacts outcome. • Multifocality of arterial occlusion is common, seen in approximately 20% of cases. • ICA false occlusion sign can be seen in setting of ICA stenosis or carotid T occlusion. • False patency sign: hyperdense thrombus/calcified occlusive plaque misinterpreted as patent vessel. • Additional abnormalities on CTA may infer stroke mechanism or alter decision making. - Abstract: Hyperacute stroke imaging is playing an increasingly important role in determining management decisions in acute stroke patients, particularly patients with large vessel occlusive stroke who may benefit from endovascular intervention. CT angiography (CTA) is an important tool in the work-up of the acute stroke patient. It reliably detects large occlusive thrombi in proximal cerebral arteries and is a quick and highly accurate method in identifying candidates for endovascular stroke treatment. In this article we review the imaging findings on CTA in acute large vessel occlusive stroke using a pictorial case based approach. We retrospectively reviewed CTA studies in 48 patients presenting with acute anterior circulation large vessel occlusive stroke who were brought for intra-arterial acute stroke intervention. We discuss and illustrate patterns of proximal intracranial arterial occlusion, collateralization to the occluded territory, as well as reviewing some important pearls, pitfalls and teaching points in CTA assessment of the acute stroke patient. Performed from the level of the aortic arch CTA also gives valuable information regarding the state of other vessels in the acute stroke patient, identifying additional significant vascular stenoses or occlusions, and as we illustrate, can demonstrate other clinically significant findings which may impact on patient management and outcome.

  15. [The value of (18)F-FDG PET/CT in diagnosing giant cell arteritis presenting as fever of unknown origin].

    Science.gov (United States)

    Liu, Yan; Zhang, Wei; Zhu, Zhaohui; Tian, Xinping; Wang, Huanling

    2014-09-01

    To evaluate the clinical diagnostic contribution of (18)F-FDG PET/CT in giant cell arteritis with initial presentation as fever of unknown origin (FUO) . Eight cases with initial presentation as FUO diagnosed with the contribution of PET/CT were retrospectively studied in Peking Union Medical College Hospital. The radiologic manifestations of PET/CT were analyzed. Eight patients (4 men and 4 women) with average (63 ± 7) years (range from 55-75 years) were included in our study based on the criteria.Non-specific clinical symptoms were common in these patients, including fatigue, night sweat and weight loss. They all suffered from anemia of chronic disease.Not surprisingly, the inflammatory parameters were elevated significantly in all patients. The medical history, physical examination and routine lab and radiologic examinations couldn't reveal the causes of fever. PET/CT was performed in all of them, which demonstrated intense (18)F-FDG uptake in the area of aorta and its major branches with maximal standard uptake value (SUVmax) 2.1- 4.6 (3.6 ± 0.9).Immunosuppressive agents were effective to control the inflammation activity. The SUV decreased significantly after treatment in the follow-up PET/CT. PET/CT has demonstrated high yield of diagnostic contribution in giant cell arteritis with initial presentation as fever of unknown origin. As to elderly FUO patients presenting with prominent inflammatory reaction, PET/CT may provide potential value to differentiate diagnosis from maligancies.

  16. Value of CT to predict surgically important bowel and/or mesenteric injury in blunt trauma: performance of a preliminary scoring system

    Energy Technology Data Exchange (ETDEWEB)

    Faget, Claire; Taourel, Patrice; Ruyer, Alban; Alili, Chakib; Millet, Ingrid [CHU Lapeyronie, Department of Medical Imaging, Montpellier (France); Charbit, Jonathan [CHU Lapeyronie, Department of Intensive Care and Anesthesiology, Montpellier (France); Molinari, Nicolas [UMR 729 MISTEA, CHU Montpellier, Department of Medical Information and Statistics, Montpellier (France)

    2015-12-15

    To evaluate the performance of a computed tomography (CT) diagnostic score to predict surgical treatment for blunt bowel and/or mesentery injury (BBMI) in consecutive abdominal trauma. This was a retrospective observational study of 805 consecutive abdominal traumas with 556 patients included and screened by an abdominal radiologist blinded to the patient outcome, to evaluate numerous CT findings and calculate their diagnostic performances. These CT findings were compared using univariate and multivariate analysis between patients who had a laparotomy-confirmed BBMI requiring surgical repair, and those without BBMI requiring surgery. A CT score was obtained with an internal bootstrap validation. Fifty-six patients (10.1 %) had BBMI requiring surgery. Nine CT signs were independently associated with BBMI requiring surgery and were used to develop a CT diagnostic score. The AUC of our model was 0.98 (95 % CI 0.96-100), with a ≥5 cut-off. Its diagnostic performance was determined by internal validation: sensitivity 91.1-100 %, specificity 85.7-97.6 %, positive predictive value 41.4-82.3 % and negative predictive value 98.9-100 %. Bowel wall discontinuity and mesenteric pneumoperitoneum had the strongest association with BBMI requiring surgery (OR = 128.9 and 140.5, respectively). We developed a reliable CT scoring system which is easy to implement and highly predictive of BBMI requiring surgery. (orig.)

  17. Construction of Abdominal Probabilistic Atlases and Their Value in Segmentation of Normal Organs in Abdominal CT Scans

    Science.gov (United States)

    Park, Hyunjin; Hero, Alfred; Bland, Peyton; Kessler, Marc; Seo, Jongbum; Meyer, Charles

    A good abdominal probabilistic atlas can provide important information to guide segmentation and registration applications in the abdomen. Here we build and test probabilistic atlases using 24 abdominal CT scans with available expert manual segmentations. Atlases are built by picking a target and mapping other training scans onto that target and then summing the results into one probabilistic atlas. We improve our previous abdominal atlas by 1) choosing a least biased target as determined by a statistical tool, i.e. multidimensional scaling operating on bending energy, 2) using a better set of control points to model the deformation, and 3) using higher information content CT scans with visible internal liver structures. One atlas is built in the least biased target space and two atlases are built in other target spaces for performance comparisons. The value of an atlas is assessed based on the resulting segmentations; whichever atlas yields the best segmentation performance is considered the better atlas. We consider two segmentation methods of abdominal volumes after registration with the probabilistic atlas: 1) simple segmentation by atlas thresholding and 2) application of a Bayesian maximum a posteriori method. Using jackknifing we measure the atlas-augmented segmentation performance with respect to manual expert segmentation and show that the atlas built in the least biased target space yields better segmentation performance than atlases built in other target spaces.

  18. Relationship between the CT Value and Cortical Bone Thickness at Implant Recipient Sites and Primary Implant Stability with Comparison of Different Implant Types.

    Science.gov (United States)

    Howashi, Miori; Tsukiyama, Yoshihiro; Ayukawa, Yasunori; Isoda-Akizuki, Kei; Kihara, Masafumi; Imai, Yu; Sogo, Motofumi; Koyano, Kiyoshi

    2016-02-01

    Studies have shown that bone quality at the implant recipient site can influence primary stability. The aims of this study were to explore the quantitative estimation of the primary stability of implants preoperatively using CT values and to examine the effect of different implant designs with recommended socket preparation on primary stability. Forty-four fresh porcine femoral heads were prepared. The bone surrounding implant sockets was preoperatively evaluated by helical CT. Forty-four implants (φ 4.3 × 10 mm), 22 straight and 22 tapered, were placed according to the manufacturer's instructions. The insertion torque value (ITV), implant stability quotient (ISQ), and removal torque value (RTV) were recorded as indicators of primary implant stability. Significant correlations and linear relationships were found between the CT value and ITV, ISQ, and RTV for both straight and tapered implants (Spearman's correlation coefficient, p quantitatively estimated using the CT value preoperatively, indicating the CT value of bone surrounding an implant can contribute considerably to implant planning and design choice in clinical situations. © 2014 Wiley Periodicals, Inc.

  19. Histogram Analysis of CT Perfusion of Hepatocellular Carcinoma for Predicting Response to Transarterial Radioembolization: Value of Tumor Heterogeneity Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Reiner, Caecilia S., E-mail: caecilia.reiner@usz.ch; Gordic, Sonja; Puippe, Gilbert; Morsbach, Fabian; Wurnig, Moritz [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology (Switzerland); Schaefer, Niklaus; Veit-Haibach, Patrick [University Hospital Zurich, Division of Nuclear Medicine (Switzerland); Pfammatter, Thomas; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology (Switzerland)

    2016-03-15

    PurposeTo evaluate in patients with hepatocellular carcinoma (HCC), whether assessment of tumor heterogeneity by histogram analysis of computed tomography (CT) perfusion helps predicting response to transarterial radioembolization (TARE).Materials and MethodsSixteen patients (15 male; mean age 65 years; age range 47–80 years) with HCC underwent CT liver perfusion for treatment planning prior to TARE with Yttrium-90 microspheres. Arterial perfusion (AP) derived from CT perfusion was measured in the entire tumor volume, and heterogeneity was analyzed voxel-wise by histogram analysis. Response to TARE was evaluated on follow-up imaging (median follow-up, 129 days) based on modified Response Evaluation Criteria in Solid Tumors (mRECIST). Results of histogram analysis and mean AP values of the tumor were compared between responders and non-responders. Receiver operating characteristics were calculated to determine the parameters’ ability to discriminate responders from non-responders.ResultsAccording to mRECIST, 8 patients (50 %) were responders and 8 (50 %) non-responders. Comparing responders and non-responders, the 50th and 75th percentile of AP derived from histogram analysis was significantly different [AP 43.8/54.3 vs. 27.6/34.3 mL min{sup −1} 100 mL{sup −1}); p < 0.05], while the mean AP of HCCs (43.5 vs. 27.9 mL min{sup −1} 100 mL{sup −1}; p > 0.05) was not. Further heterogeneity parameters from histogram analysis (skewness, coefficient of variation, and 25th percentile) did not differ between responders and non-responders (p > 0.05). If the cut-off for the 75th percentile was set to an AP of 37.5 mL min{sup −1} 100 mL{sup −1}, therapy response could be predicted with a sensitivity of 88 % (7/8) and specificity of 75 % (6/8).ConclusionVoxel-wise histogram analysis of pretreatment CT perfusion indicating tumor heterogeneity of HCC improves the pretreatment prediction of response to TARE.

  20. Spiral CT during pharmacoangiography with angiotensin II in patients with pancreatic disease. Technique and diagnostic efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Kuroda, C.; Mihara, N.; Hosomi, N.; Inoue, E.; Fujita, M. [Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan). Dept. of Diagnostic Radiology; Ohigashi, H.; Ishikawa, O. [Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan). Dept. of Surgery; Nakaizumi, A. [Osaka Medical Center for Cancer and Cardiovascular Deseases (Japan). Dept. of Internal Medicine; Ishiguro, S. [Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan). Dept. of Pathology

    1998-03-01

    Purpose: To compare the diagnostic efficacy of pancreatic pharmacoangiographic CT using angiotensin II with conventional angiographic CT. Material and Methods: Eighteen patients with space-occupying pancreatic disease were examined in this study. Pharmacoangiographic CT was performed with a 1-3-{mu}/6-ml solution of angiotensin II injected through a catheter into the celiac artery during spiral CT. Results: In 17 of the 18 (94%) patients, the area of pancreatic parenchymal enhancement was the same or larger at pharmacoangiographic CT than at conventional angiographic CT. The attenuation value of the pancreatic parenchyma was significantly increased at pharmacoangiographic CT (p=0.0010). Although the attenuation value of tumors was also increased on images obtained after the injection of angiotensin II, the tumor-to-pancreas contrast was significantly greater at pharmacoangiographic CT (p=0.0479). The mean differences in attenuation between tumor and pancreas at angiographic CT with and without angiotensin II were respectively 182 HU and 115 HU. Conclusion: Pharmacoangiographic CT with angiotensin II proved superior to conventional angiographic CT in the diagnosis of pancreatic disease. We therefore recommend it as a supplementary technique at the angiographic examination of patients with suspected pancreatic tumor. (orig.).

  1. The value of (18)F-FDG-PET/CT in diagnosis and during follow-up in 273 patients with chronic Q fever.

    Science.gov (United States)

    Kouijzer, Ilse; Kampschreur, Linda; Wever, Peter; Hoekstra, Corneline; van Kasteren, Marjo; de Jager-Leclercq, Monique; Nabuurs-Franssen, Marrigje; Wegdam-Blans, Marjolijn; Ammerlaan, Heidi; Buijs, Jacqueline; de Geus-Oei, Lioe-Fee; Oyen, Wim; Bleeker-Rovers, Chantal

    2017-05-25

    In 1-5% of all acute Q fever infections, chronic Q fever develops, mostly manifesting as endocarditis, infected aneurysms, or infected vascular prostheses. In this study, we investigated the diagnostic value of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG-PET/CT) in chronic Q fever at diagnosis and during follow-up. Methods: All Dutch adult patients suspected of chronic Q fever who were diagnosed since 2007 were retrospectively included until March 2015 when at least one (18)F-FDG-PET/CT was performed. Clinical data and results from (18)F-FDG-PET/CT at diagnosis and during follow-up were collected. (18)F-FDG-PET/CT scans were prospectively reevaluated by three nuclear medicine physicians using a structured scoring system. Results: In total, 273 patients with possible, probable, and proven chronic Q fever were included. Of all (18)F-FDG-PET/CT scans performed at diagnosis, 13.5% led to a change in diagnosis. Q fever-related mortality rate in patients with and without vascular infection based on (18)F-FDG-PET/CT was 23.8% and 2.1%, respectively (P = 0.001). When adding (18)F-FDG-PET/CT as a major criterion to the modified Duke criteria, 17 patients (1.9-fold increase) had definite endocarditis. At diagnosis, 19.6% of (18)F-FDG-PET/CT led to treatment modification. During follow-up, 57.3% of (18)F-FDG-PET/CT resulted in treatment modification. Conclusion:(18)F-FDG-PET/CT is a valuable diagnostic technique in diagnosis of chronic Q fever and during follow-up often leading to a change in diagnosis and/or treatment modification, also providing important prognostic information on patient survival. Copyright © 2017 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  2. [Diagnostic values of bronchoscopy and multi-slice spiral CT for congenital dysplasia of the respiratory system in infants: a comparative study].

    Science.gov (United States)

    Wang, Xing-Lu; Huang, Ying; Li, Qu-Bei; Dai, Ji-Hong

    2013-09-01

    To investigate and compare the diagnostic values of bronchoscopy and multi-slice spiral computed tomography (CT) for congenital dysplasia of the respiratory system in infants. Analysis was performed on the clinical data, bronchoscopic findings and multi-slice spiral CT findings of 319 infants (≤1 years old) who underwent bronchoscopy and/or multi-slice spiral CT and were diagnosed with congenital dysplasia of the respiratory system. A total of 476 cases of congenital dysplasia of the respiratory system were found in the 319 infants, including primary dysplasia of the respiratory system (392 cases) and compressive dysplasia of the respiratory system (84 cases). Of the 392 cases of primary dysplasia of the respiratory system, 225 (57.4%) were diagnosed by bronchoscopy versus 167 (42.6%) by multi-slice spiral CT. There were significant differences in etiological diagnosis between bronchoscopy and multi-slice spiral CT in infants with congenital dysplasia of the respiratory system (Pdysplasia of the respiratory system caused by tracheobronchomalacia were diagnosed by bronchoscopy and all 17 cases of primary dysplasia of the respiratory system caused by lung tissue dysplasia were diagnosed by multi-slice spiral CT. Of the 84 cases of compressive dysplasia of the respiratory system, 74 cases were diagnosed by multi-slice spiral CT and only 10 cases were diagnosed by bronchoscopy. Compared with multi-slice spiral CT, bronchoscopy can detect primary dysplasia of the respiratory system more directly. Bronchoscopy is valuable in the confirmed diagnosis of tracheobronchomalacia. Multi-slice spiral CT has a higher diagnostic value for lung tissue dysplasia than bronchoscopy.

  3. Whole-body PET/MRI: The effect of bone attenuation during MR-based attenuation correction in oncology imaging

    Energy Technology Data Exchange (ETDEWEB)

    Aznar, M.C., E-mail: marianne.aznar@regionh.dk [Department of Oncology, Section of Radiotherapy 3994, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen (Denmark); Sersar, R., E-mail: rachidadk@hotmail.com [DTU Informatics, Technical University of Denmark, Kongens Lyngby (Denmark); Saabye, J., E-mail: julie_saa@hotmail.com [DTU Informatics, Technical University of Denmark, Kongens Lyngby (Denmark); Ladefoged, C.N., E-mail: claesnl@gmail.com [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen (Denmark); Andersen, F.L., E-mail: Flemming.Andersen@regionh.dk [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen (Denmark); Rasmussen, J.H., E-mail: jacobrasmu@gmail.com [Department of Oncology, Section of Radiotherapy 3994, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen (Denmark); Löfgren, J., E-mail: Johan.Loefgren@regionh.dk [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen (Denmark); Beyer, T., E-mail: thomas.beyer@meduniwien.ac.at [Centre for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna (Austria)

    2014-07-15

    Purpose: In combined PET/MRI standard PET attenuation correction (AC) is based on tissue segmentation following dedicated MR sequencing and, typically, bone tissue is not represented. We evaluate PET quantification in whole-body (WB)-PET/MRI following MR-AC without considering bone attenuation and then investigate different strategies to account for bone tissue in clinical PET/MR imaging. To this purpose, bone tissue representation was extracted from separate CT images, and different bone representations were simulated from hypothetically derived MR-based bone classifications. Methods: Twenty oncology patients referred for a PET/CT were injected with either [18F]-FDG or [18F]-NaF and imaged on PET/CT (Biograph TruePoint/mCT, Siemens) and PET/MRI (mMR, Siemens) following a standard single-injection, dual-imaging clinical WB-protocol. Routine MR-AC was based on in-/opposed-phase MR imaging (orgMR-AC). PET(/MRI) images were reconstructed (AW-OSEM, 3 iterations, 21 subsets, 4 mm Gaussian) following routine MR-AC and MR-AC based on four modified attenuation maps. These modified attenuation maps were created for each patient by non-linear co-registration of the CT images to the orgMR-AC images, and adding CT bone mask values representing cortical bone: 1200 HU (cortCT), spongiosa bone: 350 HU (spongCT), average CT value (meanCT) and original CT values (orgCT). Relative difference images of the PET following AC using the modified attenuation maps were compared. SUVmean was calculated in anatomical reference regions and for PET-positive lesions. Results: The relative differences in SUVmean across patients following orgMR-AC and orgCT in soft tissue lesions and in bone lesions were similar (range: 0.0% to −22.5%), with an average underestimation of SUVmean of 7.2% and 10.0%, respectively when using orgMR-AC. In bone lesions, spongCT values were closest to orgCT (median bias of 1.3%, range: –9.0% to 13.5%) while the overestimation of SUVmean with respect to orgCT was

  4. CT and MRI diagnostic value for sacroiliac joint lesions in an-kylosing spondylitis%强直性脊柱炎骶髂关节病变的 CT 与 MRI 影像学诊断价值

    Institute of Scientific and Technical Information of China (English)

    李杰; 周旭峰

    2016-01-01

    目的:探讨 CT 和 MRI 对强直性脊柱炎骶髂关节病变的诊断价值。方法对80例强直性脊柱炎骶髂关节病变患者均采用螺旋 CT 和 MRI 影像检测诊断,比较两种诊断的影像表现和诊断结果。结果CT 影像 I 级诊断率为27.5%,显著低于 MRI 影像 I 级诊断率(42.5%),差异有显著性(χ2=3.96,P 0.05)。结论CT 和 MRI 均为强直性脊柱炎骶髂关节病变的有效诊断方法,二者各有其特点和不足,但 MRI 更适合早期诊断。%Objective To explore CT and MRI diagnostic value for sacroiliac joint lesions in ankylosing spondylitis (SJLAS).Methods Eighty SJLAS patients were all diagnosed using spiral CT and MRI,ima-ging manifestations and diagnostic results compared between 2 examinations.Results Class I CT diagno-sis rate was 27.5% and significantly lower than MRI (42.5%)(χ2 =3.96,P 0.05).Conclusion Both CT and MRI are effective diagnosis methods for SJLAS and have characteristics and insufficiencies, but MRI is more suitable for early diagnosis.

  5. Predictive value of 18F-fluorodeoxyglucose PET/CT for transarterial chemolipiodolization of hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Myeong Jun Song; Si Hyun Bae; Ie Ryung Yoo; Chung-Hwa Park; Jeong Won Jang; Ho Jong Chun; Byung Gil Choi

    2012-01-01

    AIM:To investigate the correlation of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) with clinical features and the prediction of treatment response.METHODS:A total of 83 hepatocellular carcinoma (HCC) patients undergoing 18F-FDG PET before transarterial chemolipiodolization with systemic chemo-infusion between October,2006 and May,2009 were retrospectively enrolled.The patients included 68 men and 15women (mean age,60 ± 10.7 years).The effect of 18F-FDG-monitored PET uptake on clinical features and on the evaluated treatment response was ascertained with modified Response Evaluation Criteria in Solid Tumors.The PET parameters of maximal standardized uptake value of the tumor (TSUVmax),the ratio of the tumor maximal standardized uptake value (SUV) to the liver maximal SUV (TSuVmax/LSuVmax) and the ratio of tumor maximal SUV to the liver mean SUV (TSuVmax/LSuVmean)were tested as predictive factors.RESULTS:Among the 3 SUV parameters,the Tsuvmax/lsuVmean ratio (cutoff value of 1.90) was significantly associated with tumor burden including tumor size,tumor number,α-fetoprotein levels and tumor stage (P <0.001,P =0.008,P =0.011,P < 0.001,respectively).The objective response rates in patients with a high SUV ratio (≥ 1.90) were significantly better than those with a low SUV ratio (< 1.90) (P =0.020).The overall survival rates of patients exhibiting a low Tsuwax/LSu-Vmean ratio (< 1.90) and those with a high SUV ratio (≥1.90) was 38.2 and 10.3 mo,respectively (P < 0.01).However,the time to progression showed no significant difference between the groups (P =0.15).CONCLUSION:18F-FDG PET can be an important predictor of HCC treatment.In particular,the Tsuvmax/LsUVmean ratio (cutoff value of 1.90) can provide useful information in treatment prognosis for HCC patients treated with locoregional therapy.

  6. Value of Perfusion CT, Transcranial Doppler Sonography, and Neurological Examination to Detect Delayed Vasospasm after Aneurysmal Subarachnoid Hemorrhage

    Directory of Open Access Journals (Sweden)

    Ekkehard Kunze

    2012-01-01

    Full Text Available Background. If detected in time, delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH may be treated by balloon angioplasty or chemical vasospasmolysis in order to enhance cerebral blood flow (CBF and protect the brain from ischemic damage. This study was conceived to compare the diagnostic accuracy of detailed neurological examination, Transcranial Doppler Sonography (TCD, and Perfusion-CT (PCT to detect angiographic vasospasm. Methods. The sensitivity, specificity, positive and negative predictive values of delayed ischemic neurological deterioration (DIND, pathological findings on PCT-maps, and accelerations of the mean flow velocity (MVF were calculated. Results. The accuracy of DIND to predict angiographic vasospasm was 0.88. An acceleration of MFV in TCD (>140 cm/s had an accuracy of 0.64, positive PCT-findings of 0.69 with a higher sensitivity, and negative predictive value than TCD. Interpretation. Neurological assessment at close intervals is the most sensitive and specific parameter for cerebral vasospasm. PCT has a higher accuracy, sensitivity and negative predictive value than TCD. If detailed neurological evaluation is possible, it should be the leading parameter in the management and treatment decisions. If patients are not amenable to detailed neurological examination, PCT at regular intervals is a helpful tool to diagnose secondary vasospasm after aneurysmal SAH.

  7. Diagnostic value of transmural perfusion ratio derived from dynamic CT-based myocardial perfusion imaging for the detection of haemodynamically relevant coronary artery stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Coenen, Adriaan; Lubbers, Marisa M.; Dedic, Admir; Chelu, Raluca G.; Geuns, Robert-Jan M. van; Nieman, Koen [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Erasmus University Medical Center, Department of Cardiology, Rotterdam (Netherlands); Kurata, Akira; Kono, Atsushi; Dijkshoorn, Marcel L. [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Rossi, Alexia [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Barts Health NHS Trust, NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London and Department of Cardiology, London (United Kingdom)

    2017-06-15

    To investigate the additional value of transmural perfusion ratio (TPR) in dynamic CT myocardial perfusion imaging for detection of haemodynamically significant coronary artery disease compared with fractional flow reserve (FFR). Subjects with suspected or known coronary artery disease were prospectively included and underwent a CT-MPI examination. From the CT-MPI time-point data absolute myocardial blood flow (MBF) values were temporally resolved using a hybrid deconvolution model. An absolute MBF value was measured in the suspected perfusion defect. TPR was defined as the ratio between the subendocardial and subepicardial MBF. TPR and MBF results were compared with invasive FFR using a threshold of 0.80. Forty-three patients and 94 territories were analysed. The area under the receiver operator curve was larger for MBF (0.78) compared with TPR (0.65, P = 0.026). No significant differences were found in diagnostic classification between MBF and TPR with a territory-based accuracy of 77 % (67-86 %) for MBF compared with 70 % (60-81 %) for TPR. Combined MBF and TPR classification did not improve the diagnostic classification. Dynamic CT-MPI-based transmural perfusion ratio predicts haemodynamically significant coronary artery disease. However, diagnostic performance of dynamic CT-MPI-derived TPR is inferior to quantified MBF and has limited incremental value. (orig.)

  8. Post-therapy surveillance of patients with uterine cancers: value of integrated FDG PET/CT in the detection of recurrence

    Energy Technology Data Exchange (ETDEWEB)

    Sironi, Sandro [University of Milano-Bicocca, School of Medicine, Milan (Italy); IBFM-CNR, Institute for Molecular Bioimaging and Physiology, Milan (Italy); H S. Gerardo Monza, Department of Diagnostic Radiology, Milan (Italy); Picchio, Maria; Bettinardi, Valentino [Scientific Institute San Raffaele, Department of Nuclear Medicine, Milan (Italy); Landoni, Claudio [University of Milano-Bicocca, School of Medicine, Milan (Italy); Scientific Institute San Raffaele, Department of Nuclear Medicine, Milan (Italy); Galimberti, Stefania [University of Milano-Bicocca, School of Medicine, Milan (Italy); University of Milano-Bicocca, Department of Clinical Medicine Prevention and Biotechnology, Section of Medical Statistics, Milan (Italy); Signorelli, Mauro [H S. Gerardo Monza, Department of Gynecology and Obstetrics, Milan (Italy); Perego, Patrizia [H S. Gerardo Monza, Department of Pathology, Milan (Italy); Mangioni, Costantino [University of Milano-Bicocca, School of Medicine, Milan (Italy); H S. Gerardo Monza, Department of Gynecology and Obstetrics, Milan (Italy); Messa, Cristina [University of Milano-Bicocca, School of Medicine, Milan (Italy); IBFM-CNR, Institute for Molecular Bioimaging and Physiology, Milan (Italy); H S. Gerardo Monza, Department of Nuclear Medicine, Milan (Italy); Fazio, Ferruccio [University of Milano-Bicocca, School of Medicine, Milan (Italy); IBFM-CNR, Institute for Molecular Bioimaging and Physiology, Milan (Italy); Scientific Institute San Raffaele, Department of Nuclear Medicine, Milan (Italy)

    2007-04-15

    The purpose of this study was to prospectively determine the diagnostic accuracy of PET/CT in the detection of recurrence in patients with treated uterine cancers. Twenty-five women, ranging in age from 37 to 79 years (mean 58.9 years), who underwent primary surgical treatment for either a cervical or an endometrial cancer met the inclusion criterion of the study, which was suspicion of recurrence based on results of routine follow-up procedures. PET/CT was performed after administration of {sup 18}F-fluorodeoxyglucose (FDG); two readers interpreted the images in consensus. Histopathological findings or correlation with results of subsequent clinical and imaging follow-up examinations served as the reference standard. Diagnostic accuracy of PET/CT was reported in terms of the proportion of correctly classified patients and lesion sites. Tumour recurrence was found at histopathological analysis or follow-up examinations after PET/CT in 14 (56%) of the 25 patients. Patient-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy of PET/CT for detection of tumour recurrence were 92.9%, 100.0%, 100.0%, 91.7% and 96.0%, respectively. Lesion site-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy of PET/CT were 94.7%, 99.5%, 94.7%, 99.5% and 99.0%, respectively. This preliminary study shows that PET/CT may be an accurate method for the evaluation of recurrence in patients who have been treated for uterine cancers and are undergoing follow-up. (orig.)

  9. The value of FDG-PET/CT in the diagnostic work-up of extra cardiac infectious manifestations in infectious endocarditis

    DEFF Research Database (Denmark)

    Ozcan, C; Asmar, A; Gill, S;

    2013-01-01

    Infectious endocarditis (IE) is a serious condition with a high morbidity and mortality. The optimal management of IE depends not only on correct antibiotic therapy and surgery when needed, but involves identification of the portal of entry and detection of extracardiac infectious manifestations....... To discover the latter an (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET)/CT examination has been proposed. However, the diagnostic value of a PET/CT in this setting remains unresolved. Thus, we wished to assess the usefulness of a PET/CT study in patients with IE as a supplemental...... method to standard work-up in evaluating primary and distant infective foci. A retrospective cohort study of 72 IE patients admitted from 2008 to 2010, which had an (18)F-FDG-PET/CT performed. Findings were assessed in relation to the routine work-up, which served as the "gold standard". One hundred...

  10. A New Proton CT Scanner

    CERN Document Server

    Coutrakon, G; Boi, S; Dyshkant, A; Erdelyi, B; Hedin, D; Johnson, E; Krider, J; Rykalin, V; Uzunyan, S A; Zutshi, V; Fordt, R; Sellberg, G; Rauch, J E; Roman, M; Rubinov, P; Wilson, P; Naimuddin, M

    2014-01-01

    The design, construction, and preliminary testing of a second generation proton CT scanner is presented. All current treatment planning systems at proton therapy centers use X-ray CT as the primary imaging modality for treatment planning to calculate doses to tumor and healthy tissues. One of the limitations of X-ray CT is in the conversion of X-ray attenuation coefficients to relative (proton) stopping powers, or RSP. This results in more proton range uncertainty, larger target volumes and therefore, more dose to healthy tissues. To help improve this, we present a novel scanner capable of high dose rates, up to 2~MHz, and large area coverage, 20~x~24~cm$^2$, for imaging an adult head phantom and reconstructing more accurate RSP values.

  11. Diagnostic Value of CT Arthrography for Evaluation of Osteochondral Lesions at the Ankle

    Directory of Open Access Journals (Sweden)

    Jan S. Kirschke

    2016-01-01

    Full Text Available Background. To retrospectively determine the diagnostic value of computed tomography arthrography (CTA of the ankle in the evaluation of (osteochondral lesions in comparison to conventional magnetic resonance imaging (MRI and intraoperative findings. Methods. A total of N=79 patients had CTAs and MRI of the ankle; in 17/79 cases surgical reports with statements on cartilage integrity were available. Cartilage lesions and bony defects at talus and tibia were scored according to defect depth and size by two radiologists. Statistical analysis included sensitivity analyses and Cohen’s kappa calculations. Results. On CTA, 41/79 and 31/79 patients had full thickness cartilage defects at the talus and at the tibia, respectively. MRI was able to detect 54% of these defects. For the detection of full thickness cartilage lesions, interobserver agreement was substantial (0.72 ± 0.05 for CTA and moderate (0.55 ± 0.07 for MRI. In surgical reports, 88–92% and 46–62% of full thickness defects detected by CTA and MRI were described. CTA findings changed the further clinical management in 15.4% of cases. Conclusions. As compared to conventional MRI, CTA improves detection and visualization of cartilage defects at the ankle and is a relevant tool for treatment decisions in unclear cases.

  12. Diagnostic value of time-resolved CT angiography for the lower leg.

    Science.gov (United States)

    Sommer, Wieland H; Helck, Andreas; Bamberg, Fabian; Albrecht, Edda; Becker, Christoph R; Weidenhagen, Rolf; Kramer, Harald; Reiser, Maximilian F; Nikolaou, Konstantin

    2010-12-01

    The aim of this study was to test the feasibility of time-resolved computed tomography angiography (TR-CTA) for use in the lower leg. Fifty-nine patients with suspected peripheral arterial occlusive disease were examined with a standard CTA (S-CTA) of the lower run-off and with an additional TR-CTA of the calves (12 phases; 2.5 s/phase, 80 kV, 120 mAs, volume of contrast medium 50 mL, flow rate 5.0 mL/s). For seven lower-leg artery segments, arterial contrast and the presence of venous overlay were tested for S-CTA and TR-CTA. Stenoses were classified on a three-point scale separately for S-CTA and TR-CTA, and diagnostic confidence for stenosis assessment was evaluated for both datasets. Contrast arrival times and HU values were evaluated in patients with asymmetric proximal stenoses. TR-CTA resulted in significantly higher contrast enhancement (P < 0.0001) and less venous overlay as compared to S-CTA (P < 0.05). Diagnostic confidence for stenosis rating was significantly higher in TR-CTA (P < 0.0001). Asymmetric proximal stenoses lead to significantly delayed and diminished contrast enhancement on the stenotic side. TR-CTA of the calves is feasible and provides higher enhancement and higher diagnostic confidence as compared to monophasic CTA of the lower legs.

  13. Diagnostic value of time-resolved CT angiography for the lower leg

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, Wieland H. [Ludwig-Maximilians University Munich, Department of Clinical Radiology, University Hospital-Grosshadern, Munich (Germany); University of Munich, Grosshadern Campus, Department of Clinical Radiology, Munich (Germany); Helck, Andreas; Bamberg, Fabian; Albrecht, Edda; Becker, Christoph R.; Kramer, Harald; Reiser, Maximilian F.; Nikolaou, Konstantin [Ludwig-Maximilians University Munich, Department of Clinical Radiology, University Hospital-Grosshadern, Munich (Germany); Weidenhagen, Rolf [Ludwig-Maximilians University Munich, Department of Surgery, University Hospital-Grosshadern, Munich (Germany)

    2010-12-15

    The aim of this study was to test the feasibility of time-resolved computed tomography angiography (TR-CTA) for use in the lower leg. Fifty-nine patients with suspected peripheral arterial occlusive disease were examined with a standard CTA (S-CTA) of the lower run-off and with an additional TR-CTA of the calves (12 phases; 2.5 s/phase, 80 kV, 120 mAs, volume of contrast medium 50 mL, flow rate 5.0 mL/s). For seven lower-leg artery segments, arterial contrast and the presence of venous overlay were tested for S-CTA and TR-CTA. Stenoses were classified on a three-point scale separately for S-CTA and TR-CTA, and diagnostic confidence for stenosis assessment was evaluated for both datasets. Contrast arrival times and HU values were evaluated in patients with asymmetric proximal stenoses. TR-CTA resulted in significantly higher contrast enhancement (P < 0.0001) and less venous overlay as compared to S-CTA (P < 0.05). Diagnostic confidence for stenosis rating was significantly higher in TR-CTA (P < 0.0001). Asymmetric proximal stenoses lead to significantly delayed and diminished contrast enhancement on the stenotic side. TR-CTA of the calves is feasible and provides higher enhancement and higher diagnostic confidence as compared to monophasic CTA of the lower legs. (orig.)

  14. A semi-automated technique determining the liver standardized uptake value reference for tumor delineation in FDG PET-CT.

    Directory of Open Access Journals (Sweden)

    Kenji Hirata

    Full Text Available BACKGROUND: 18F-fluorodeoxyglucose (FDG positron emission tomography (PET-computed tomography (CT has been an essential modality in oncology. We propose a semi-automated algorithm to objectively determine liver standardized uptake value (SUV, which is used as a threshold for tumor delineation. METHODS: A large spherical volume of interest (VOI was placed manually to roughly enclose the right lobe (RL of the liver. For each voxel in this VOI, a coefficient of variation of voxel values (CVv was calculated for neighboring voxels within a radius of d/2. The voxel with the minimum CVv was then selected, where a 30-mm spherical VOI was placed at that voxel in accordance with PERCIST criteria. Two nuclear medicine physicians independently defined 30-mm VOIs manually on 124 studies in 62 patients to generate the standard values, against which the results from the new method were compared. RESULTS: The semi-automated method was successful in determining the liver SUV that was consistent between the two physicians in all the studies (d = 80 mm. The liver SUV threshold (mean +3 SD within 30-mm VOI determined by the new semi-automated method (3.12±0.61 was not statistically different from those determined by the manual method (Physician-1: 3.14±0.58, Physician-2: 3.15±0.58. The semi-automated method produced tumor volumes that were not statistically different from those by experts' manual operation. Furthermore, the volume change in the two sequential studies had no statistical difference between semi-automated and manual methods. CONCLUSIONS: Our semi-automated method could define the liver SUV robustly as the threshold value used for tumor volume measurements according to PERCIST. The method could avoid possible subjective bias of manual liver VOI placement and is thus expected to improve clinical performance of volume-based parameters for prediction of cancer treatment response.

  15. Diagnostic value of 64-slice spiral CT angiography in the diagnosis of multiple intracranial aneurysms: a report of 25 cases

    Directory of Open Access Journals (Sweden)

    Hong-sheng WANG

    2013-02-01

    Full Text Available Objective  To evaluate the diagnostic value of 64-slice spiral CT angiography (CTA in multiple intracranial aneurysms (MIA. Methods  Twenty-five patients (9 males and 16 females, aged from 17 to 68 years with suspected MIA underwent 64-slice spiral CTA with slice thickness of 0.625mm. The data of all patients were reconstructed with multiplanar reconstruction (MPR, 3-dimensional shade surface display (3-SSD, volume rendering (VR and maximum intensity projection (MIP. The clinical diagnostic value was evaluated with the results of surgery or interventional embolization therapy. Results  A total of 61 aneurysms were detected by 64-slice spiral CTA in 25 patients, among them 17 patients were with 2 aneurysms, 6 patients with 3 aneurysms, 1 patient with 4 aneurysms and 1 patient with 5 aneurysms. The 64-slice spiral CTA could not only clearly demonstrate MIA, but also the size, neck, axis point and parent artery of each aneurysm, and the spatial relationship between aneurysm and the adjacent vessels and bone structures. Twenty-one patients underwent microsurgery and four underwent embolization, the location, size and shape of aneurysm and its spatial relationship with adjacent structures were in accordance with the findings of 64-slice spiral CTA. Conclusion  The 64-slice spiral CTA could be used as the first choice in the diagnosis of MIA for its high accuracy, and may be an important adjunct to digital subtraction angiography (DSA in MIA treatment.

  16. PET-CT和CT在肺癌射频消融术后的应用价值%The value of PET-CT and CT in the assessment after radiofrequency ablation in lung cancer

    Institute of Scientific and Technical Information of China (English)

    朱广卿; 晋颖; 张淼; 张玉珍; 元霄梅; 李立伟; 宋云龙

    2012-01-01

    Objective To explore the value of PET-CT and CT in the assessment after radiofrequency ablation (RFA) in lung cancer.Methods Eighteen patients were randomly divided into short-term group ( 8 cases) and long-term group ( 10 cases).Patients in short-term group received PET-CT and CT examination within 10 days after RFA therapy,whereas those in long-term group got PET-CT and CT examination within 2 months after RFA therapy.The value of PET-CT and CT after RFA therapy through the result of the image was compared between two groups.Results All patients were classified as stable disease in CT,while in PET-CT assessment,33.33% (6/18) of the patients presented complete remission and 66.67% (12/18)presented partial remission.37.50% (3/8) of short-term group presented complete remission,62.50% (5/8) of short-term group presented partial remission.30.00% (3/10) of long-term group presented complete remission,70.00%(7/l0) of long-term group presented partial remission.Conclusion PET-CT is superior to CT in the assessment of the effectiveness of RFA therapy,and there is no difference between short-term and long-term PET-CT examination,therefore early PET-CT is more with clinical significance.%目的 探讨PET-CT和CT在肺癌射频消融术后的应用价值.方法 接受射频消融治疗的18例肺癌患者按随机数字表法分为两组:近期组(8例)术后10d及10d以内接受PET-CT和CT检查,远期组(10例)术后2个月接受PET-CT和CT检查,比较两组PET-CT与CT在射频消融术后评价疗效的差异.结果 射频消融术后CT的评价结果100.00%( 18/18)为病灶稳定.而PET-CT评价33.33%(6/18)为完全缓解,66.67%(12/18)为部分缓解,近期组37.50%( 3/8)为完全缓解,62.50%( 5/8)为部分缓解,远期组30.00% (3/10)为完全缓解,70.00%(7/10)为部分缓解.结论 在肺癌射频消融术后评价中,PET-CT较CT更加精确,早期PET-CT检查和远期PET-CT评价结果相近,均可准确评估疗效,因此早期PET-CT检查更具有临床意义.

  17. CT-VRT重建技术对腰骶部隐性脊柱裂的诊断价值%Diagnostic values of lumbosacral vertebrae spina bifida occulta with CT-VRT

    Institute of Scientific and Technical Information of China (English)

    张笑春; 季冰; 王健; 屈清华; 陈霖; 吴宗乾; 黎海涛

    2012-01-01

    目的 评估CT容积漫游技术(CT-VRT)重建对腰骶部隐性脊柱裂(SBO)的诊断价值.方法 回顾性分析212例腰骶部隐性脊柱裂的骨盆X线平片和CT-VRT的影像特征,包括对称性、形态、范围和受累椎体及脊柱节段,并比较两种检查手段对骨质缺如的影像特征的显示情况.结果 在显示SBO对称性、形态、范围、受累椎体及脊柱节段和游离骨脊等方面,CT-VRT比X线平片准确(P0.05).结论 X线平片和CT是检查SBO的有效手段,CT-VRT能够直观、立体、更准确的显示SBO形态、范围和受累椎体及脊柱节段,鉴别真、假裂隙样骨质缺如,并进一步确定假裂隙样骨质缺失的本质.%Objective To evaluate the diagnostic value of plain film and CT volume rendering technique ( CT-VRT) reconstruction in SBO. Methods Retrospectively evaluated and compared the imaging features in 212 patients with lumbosacral vertebrae spina bifida occulta ( SBO ),including symmetry,shape,range,affected vertebral body and segment of vertebral column. Imaging features of bone absence were e-valuated with plain film and CT-VRT. Results CT-VRT exhibited more accurate shape, range, affected vertebral body and segment of vertebral column of SBO than plain film( P 0. 05 ). Conclusion Plain film and CT-VRT are effective methods. CT-VRT could exhibit shape, range, affected vertebral body and segment of vertebral column of SBO more accurately, and identify the facticity of fiss-shape bone absence, and make further research to obtained the essence of fiss-shape bone absence.

  18. CT angiography and CT perfusion in acute ischemic stroke

    NARCIS (Netherlands)

    Seeters, T. van

    2016-01-01

    CT angiography and CT perfusion are used in patients with acute ischemic stroke for diagnostic purposes and to select patients for treatment. In this thesis, the reproducibility of CT angiography and CT perfusion is examined, the additional value of CT angiography and CT perfusion for stroke outcome

  19. Comparison of the diagnostic value of FDG-PET/CT and axillary ultrasound for the detection of lymph node metastases in breast cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Riegger, Carolin; Heusner, Till A. [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf (Germany); Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany)], E-mail: Heusner@med.uni-duesseldorf.de; Koeninger, Angela; Kimmig, Rainer [Univ Duisburg-Essen, Medical Faculty, Department of Gynecology and Obstetrics, Essen (Germany); Hartung, Verena; Bockisch, Andreas [Univ Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, Essen (Germany); Otterbach, Friedrich [Univ Duisburg-Essen, Institute of Pathology and Neuropathology, Essen (Germany); Forsting, Michael [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Antoch, Gerald [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf (Germany)

    2012-12-15

    Background. FDG-PET/CT is increasingly being used for breast cancer staging. Its diagnostic accuracy in comparison to ultrasound as the standard non-invasive imaging modality for the evaluation of axillary lymph nodes has yet not been evaluated. Purpose. To retrospectively compare the diagnostic value of full-dose, intravenously contrast-enhanced FDG-PET/CT and ultrasound for the detection of lymph node metastases in breast cancer patients. Material and Methods. Ninety patients (one patient with a bilateral carcinoma) (89 women, one man; mean age, 55.5 {+-} 16.6 years) suffering from primary breast cancer underwent whole-body FDG-PET/CT and axillary ultrasound. The ipsilateral axillary fossa (n = 91) was evaluated for metastatic spread. The sensitivity, specificity, the positive predictive value (PPV), negative predictive value (NPV), and accuracy of both methods were calculated. The sensitivity and accuracy were statistically compared using the McNemar Test (P <0.05). Analyses were made on a patient basis. The number of patients with extra-axillary locoregional lymph node metastases exclusively detected by FDG-PET/CT was evaluated. For axillary lymph node metastases histopathology served as the reference standard. Results. The sensitivity, specificity, PPV, NPV, and accuracy of FDG-PET/CT for the detection of axillary lymph node metastases were 54%, 89%, 77%, 74%, and 75%, respectively. For ultrasound it was 38%, 78%, 54%, 65%, and 62%, respectively. FDG-PET/CT was significantly more accurate than ultrasound for the detection of axillary lymph node metastases (P = 0.019). There was no statistically significant difference between the sensitivity of both modalities (P = 0.0578). FDG-PET/CT detected extra-axillary locoregional lymph node metastases in seven patients (8%) that had not been detected by another imaging modality. Conclusion. Though more accurate compared to ultrasound for evaluating the axillary lymph node status FDG-PET/CT is only as sensitive as

  20. Venous thromboembolism: Additional diagnostic value and radiation dose of pelvic CT venography in patients with suspected pulmonary embolism

    Energy Technology Data Exchange (ETDEWEB)

    Reichert, Miriam, E-mail: Miriam.Reichert@umm.de [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany); Henzler, Thomas; Krissak, Radko; Apfaltrer, Paul [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany); Huck, Kurt [1st Department of Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim (Germany); Buesing, Karen [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany); Sueselbeck, Tim [1st Department of Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim (Germany); Schoenberg, Stefan O.; Fink, Christian [Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany)

    2011-10-15

    Purpose: To assess the additional diagnostic value of indirect CT venography (CTV) of the pelvis and upper thighs performed after pulmonary CT angiography (CTA) for the diagnosis of venous thromboembolism (VTE). Materials and methods: In a retrospective analysis, the radiology information system entries between January 2003 and December 2007 were searched for patients who received pulmonary CTA and additional CTV of the pelvis and upper thighs. Of those patients, the radiology reports were reviewed for the diagnosis of pulmonary embolism (PE) and deep venous thrombosis (DVT) in the pelvic veins and veins of the upper thighs. In cases with an isolated pelvic thrombosis at CTV (i.e. which only had a thrombosis in the pelvic veins but not in the veins of the upper thigh) ultrasound reports were reviewed for the presence of DVT of the legs. The estimated radiation dose was calculated for pulmonary CTA and for CTV of the pelvis. Results: In the defined period 3670 patients were referred to our institution for exclusion of PE. Of those, 642 patients (353 men, 289 women; mean age, 65 {+-} 15 years, age range 18-98 years) underwent combined pulmonary CTA and CTV. Among them, PE was found in 227 patients (35.4%). In patients without PE CTV was negative in all cases. In patients with PE, CTV demonstrated pelvic thrombosis in 24 patients (3.7%) and thrombosis of the upper thighs in 43 patients (6.6%). Of those patients 14 (2.1%) had DVT in the pelvis and upper thighs. In 10 patients (1.5%) CTV showed an isolated pelvic thrombosis. Of those patients ultrasound reports were available in 7 patients, which revealed DVT of the leg veins in 5 cases (1%). Thus, the estimated prevalence of isolated pelvic thrombosis detected only by pelvic CTV ranges between 1-5/642 patients (0.1-0.7%). Radiation dose ranges between 4.8 and 9.7 mSv for additional CTV of the pelvis. Conclusion: CTV of the pelvis performed after pulmonary CTA is of neglectable additional diagnostic value for the

  1. Transluminal attenuation gradient in coronary computed tomography angiography for determining stenosis severity of calcified coronary artery: a primary study with dual-source CT

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Minwen; Wei, Mengqi; Wen, Didi; Zhao, Hongliang; Liu, Ying; Li, Jian [Fourth Military Medical University, Department of Radiology, Xijing Hospital, Xi' an, Shaanxi Province (China); Li, Jiayi [Fourth Military Medical University, Department of Cardiology, Xijing Hospital, Xi' an, Shaanxi Province (China)

    2015-05-01

    To evaluate the diagnostic accuracy of transluminal attenuation gradient (TAG) for stenosis severity of calcified lesions assessed by coronary computed tomography angiography (CCTA). One hundred seven patients who underwent CCTA and coronary angiography (CAG) were enrolled. TAGs of 309 major epicardial coronary arteries were measured. The impact of plaque composition, Agatston scores, and lesion length ratio on TAG were analyzed. Diagnostic performance vs. CAG of TAG, CCTA, and combined TAG/CCTA were evaluated, and incremental value of TAG for reclassification of CCTA stenosis severity in calcified lesions was also analyzed. TAG decreased consistently with stenosis severity. TAG was significantly lower in coronary arteries with calcification scores >300 and lesion length ratios >2/3. TAG improved diagnostic accuracy of CCTA (c-statistic =0.982 vs. 0.942, P = 0.0001) in calcified lesions, and the sensitivity, specificity, positive, and negative predictive values of TAG cutoff ≤ -11.33 were 72 %, 91 %, 88 %, and 78 %, respectively. The addition of TAG to CCTA resulted in significant reclassification (NRI =0.093, P = 0.022) in calcified vessels. Measurement of TAG may improve diagnostic performance and reclassification of CCTA in coronary stenosis caused by calcified lesions. (orig.)

  2. The added value of {sup 68}Ga-DOTA-TATE-PET to contrast-enhanced CT for primary site detection in CUP of neuroendocrine origin

    Energy Technology Data Exchange (ETDEWEB)

    Kazmierczak, Philipp M. [Klinikum der Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany); Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Muenchen (Germany); Rominger, Axel; Wenter, Vera [Ludwig-Maximilians-University Hospital Munich, Department of Nuclear Medicine, Muenchen (Germany); Spitzweg, Christine; Auernhammer, Christoph [Ludwig-Maximilians-University Hospital Munich, Department of Internal Medicine II, Muenchen (Germany); Angele, Martin K. [Ludwig-Maximilians-University Hospital Munich, Department of General, Visceral, Transplantation, Vascular and Thoracic Surgery, Muenchen (Germany); Rist, Carsten; Cyran, Clemens C. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Muenchen (Germany)

    2017-04-15

    To quantify the additional value of {sup 68}Ga-DOTA-TATE PET/CT in comparison with contrast-enhanced CT alone for primary tumour detection in neuroendocrine cancer of unknown primary (CUP-NET). In total, 38 consecutive patients (27 men, 11 women; mean age 62 years) with histologically proven CUP-NET who underwent a contrast-enhanced {sup 68}Ga-DOTA-TATE PET/CT scan for primary tumour detection and staging between 2010 and 2014 were included in this IRB-approved retrospective study. Two blinded readers independently analysed the contrast-enhanced CT and {sup 68}Ga-DOTA-TATE PET datasets separately and noted from which modality they suspected a primary tumour. Consensus was reached if the results were divergent. Postoperative histopathology (24 patients) and follow-up {sup 68}Ga-DOTA-TATE PET/CT imaging (14 patients) served as the reference standards and statistical measures of diagnostic accuracy were calculated accordingly. The majority of confirmed primary tumours were located in the abdomen (ileum in 19 patients, pancreas in 12, lung in 2, small pelvis in 1). High interobserver agreement was noted regarding the suspected primary tumour site (Cohen's k 0.90, p < 0.001). {sup 68}Ga-DOTA-TATE PET demonstrated a significantly higher sensitivity (94 % vs. 63 %, p = 0.005) and a significantly higher accuracy (87 % vs. 68 %, p = 0.003) than contrast-enhanced CT. Ga-DOTA-TATE PET/CT compared with contrast-enhanced CT alone provides an improvement in sensitivity of 50 % and an improvement in accuracy of 30 % in primary tumour detection in CUP-NET. (orig.)

  3. 多排螺旋CT 诊断小网膜囊病变的价值%Diagnostic value of multi-detector CT for abnormalities in lesser omental bursa

    Institute of Scientific and Technical Information of China (English)

    成峰; 吴凯宏; 李孝虎

    2011-01-01

    目的 探讨小网膜囊正常解剖及病变的多排螺旋CT(MDCT)表现,评价小网膜囊病变的CT 诊断价值.方法 对24 例小网膜囊病变进行上腹部CT 平扫及三期增强扫描检查,均经手术病理证实.结果 小网膜囊病变中:原发肿瘤6 例(神经鞘瘤2 例,平滑肌瘤1 例,血管瘤1 例,脂肪肉瘤1 例,淋巴瘤1 例),CT 表现为小网膜囊内边界清晰肿块.邻近脏器的良、恶性肿瘤8 例(胰头癌4 例,肝左叶肝细胞癌2 例,胃间质瘤2 例),CT 表现为小网膜囊肿块与邻近相应肿瘤边界不清.转移性肿瘤2 例.结核1 例,CT 表现多个病灶融合,内见钙化.积液(腹水漏出液、炎性渗出液、脓液、血液、胆汁、淋巴液)6 例;假性囊肿1 例;CT 均表现为小网膜囊内液性密度灶.结论 多排螺旋CT对小网膜囊病变具有重要的诊断价值.%Objective To investigate the normal CT anatomy and diagnostic value of CT for abnormalities of lesser omental bursa. Methods Twenty-four patients with 6 primary neoplasms (2 neurinomas, 1 leiomyoma, 1 cavernous hemangioma, 1 liposarcoma, 1 lymphoma), 8 local spread from adjacent benign or malignant neoplasms (4 carcinomas of head of pancreas, 2 left hepatic tumors, 2 gastrointestinal stromal tumors of the stomach), 2 metastatic tumors, 1 tuberculosis, 6 fluid collections (transudate ascites, inflammatory infiltrate, pus, blood, bile, lymph), lpseudocyst were enrolled in the study. All of the lesions were confirmed by operation and pathology. The pre- and post-contrast abdominal CT scans were reviewed. Results The borders of the 6 primary neoplasms were well-defined on CT whereas the 8 benign or malignant neoplasms originating from adjacent structures were contiguous with the primary tumors. CT showed multiple aggregated lesions on 2 patients with metastases and 1 patient with tuberculosis. The 6 fluid collections and lpseudocyst displayed fluid density within lesser omental bursa on CT. Conclusion CT is valuable in

  4. Quantitative dual energy CT measurements in rabbit VX2 liver tumors: Comparison to perfusion CT measurements and histopathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Long Jiang, E-mail: kevinzhanglongjiang@yahoo.com.cn [Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, 305 Zhongshan East Road, Xuanwu District, Nangjing, Jiangsu Province 210002 (China); Wu, Shengyong, E-mail: cjr.wushengyong@vip.163.com [Institute of Tianjin Medical Imaging, Tianjin 300192 (China); Wang, Mei, E-mail: 281406196@qq.com [Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, 305 Zhongshan East Road, Xuanwu District, Nangjing, Jiangsu Province 210002 (China); Lu, Li, E-mail: xuzhoululi@163.com [Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, 305 Zhongshan East Road, Xuanwu District, Nangjing, Jiangsu Province 210002 (China); Chen, Bo, E-mail: chenbo1985@yahoo.com.cn [Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, 305 Zhongshan East Road, Xuanwu District, Nangjing, Jiangsu Province 210002 (China); Jin, Lixin, E-mail: lixin.jin@siemens.com [Siemens Healthcare, MR Collaboration NE Asia, Shanghai (China); Wang, Jiandong, E-mail: jdwang1216@163.com [Department of Pathology, Jinling Hospital, Clinical School of Medical College, Nanjing University, 305 Zhongshan East Road, Xuanwu District, Nangjing, Jiangsu Province 200012 (China); Larson, Andrew C., E-mail: a-larson@northwestern.edu [Department of Radiology, Northwestern University, Chicago, IL (United States); Lu, Guang Ming, E-mail: cjr.luguangming@vip.163.com [Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, 305 Zhongshan East Road, Xuanwu District, Nangjing, Jiangsu Province 210002 (China)

    2012-08-15

    Purpose: To evaluate the correlation between quantitative dual energy CT and perfusion CT measurements in rabbit VX2 liver tumors. Materials and methods: This study was approved by the institutional animal care and use committee at our institution. Nine rabbits with VX2 liver tumors underwent contrast-enhanced dual energy CT and perfusion CT. CT attenuation for the tumors and normal liver parenchyma and tumor-to-liver ratio were obtained at the 140 kVp, 80 kVp, average weighted images and dual energy CT iodine maps. Quantitative parameters for the viable tumor and adjacent liver were measured with perfusion CT. The correlation between the enhancement values of the tumor in iodine maps and perfusion CT parameters of each tumor was analyzed. Radiation dose from dual energy CT and perfusion CT was measured. Results: Enhancement values for the tumor were higher than that for normal liver parenchyma at the hepatic arterial phase (P < 0.05). The highest tumor-to-liver ratio was obtained in hepatic arterial phase iodine map. Hepatic blood flow of the tumor was higher than that for adjacent liver (P < 0.05). Enhancement values of hepatic tumors in the iodine maps positively correlated with permeability of capillary vessel surface (r = 0.913, P < 0.001), hepatic blood flow (r = 0.512, P = 0.010), and hepatic blood volume (r = 0.464, P = 0.022) at the hepatic arterial phases. The effective radiation dose from perfusion CT was higher than that from DECT (P < 0.001). Conclusions: The enhancement values for viable tumor tissues measured in iodine maps were well correlated to perfusion CT measurements in rabbit VX2 liver tumors. Compared with perfusion CT, dual energy CT of the liver required a lower radiation dose.

  5. Comparing SUV values of images at PET-CT console and the RT planning console using identical dataset of a study phantom

    Directory of Open Access Journals (Sweden)

    Anusheel Munshi

    2016-01-01

    Conclusions: Our study found out that the average difference in the two systems for maximum SUV values was < 0.2 absolute units.Our study suggests good reproducibility of SUV between the two systems. The relevance of these findings would be of seminal importance in current and future SUV-based PET-CT-based contouring in treatment planning systems.

  6. The value of routine bone marrow biopsy in patients with diffuse large B-cell lymphoma staged with PET/CT

    DEFF Research Database (Denmark)

    Alzahrani, M; El-Galaly, T C; Hutchings, M

    2016-01-01

    BACKGROUND: The added diagnostic and prognostic value of routine bone marrow biopsy (BMB) in patients with diffuse large B-cell lymphoma (DLBCL) undergoing positron emission tomography combined with computed tomography (PET/CT) staging is controversial. PATIENTS AND METHODS: Patients with newly d...

  7. Value of CT in salivary gland tumors diagnostic. Valor de la TC en el diagnostico de los tumores de glandulas salivares

    Energy Technology Data Exchange (ETDEWEB)

    Navarro Sanchis, E.; Valdes Solis, P.; Sanchez Lafuente, J.; Rodiguez Sanpedro, F.

    1993-10-01

    Salivary gland tumors represent 3% of all tumors; 80% of them are located in the parotid glands. We present a series of 18 salivary gland tumors, all of which were studied by means of CT with infusion dynamic intravenous contrast, and we analyze the semiological data obtained and the value of computerized tomography in the diagnosis of these tumors. Author (15 refs.)

  8. 48. The value of CT scan and detection of telomerase activity in biopsy specimens for early diagnosis of lung carcinoma

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To evaluate the diagnostic value of telomerase activity in the specimens of biopsy with bronchoscopy or cutting needle. Methods: Telomerase activity was measured in the biopsy apecimens taken from 52 patients suspected of having early lung cancer by CT scan. The PCR based silver staining telomeric repeat amplification protocol (TRAP) was used for detection of telomerase activity in 22 patients with early lung cancer (T1N0M0). Control study was made on the specimens taken from 24 patients with benign disease (cyst 3, TB 6, pseudtumor 5, pneumonjia 10). Results: The positive rates of telomerase activity were 86.45% (19/22) and 4.2% (1/24) in early lung cancers and benign lesions respectively (P<0.01). It was significantly higher in early lung cancers than in benign disease. All cases were diagnosed with surgical pathology and following for 2 years. Conclusion: Detecting telomerase activity in preoperative bronchoscope and cutting needle biopsy specimens may contribute to diagnosis of early lung cancer.

  9. [Clinical value of toes periungual green-coloured voxels of dual-energy CT gout detecting technology].

    Science.gov (United States)

    Li, Huixia; Qu, Jin; Zhan, Ying; Lei, Xinwei

    2015-10-20

    To evaluate the clinical value of dual-energy CT(DECT) in the detection of green-coloured voxels in toenails in patients with gout using DECT. A total of 53 patients with gout could be included in the study composed of 45 men and 8 women, and 33 individuals without gout were regarded as control group. There were no significant differences in gender and age between two groups. DECT were performed for the both feet, DE (80 kV and 140 kV) datasets were reconstructed via gout-recognition software, the pseudo-color images group as the postprocessed group.Imagings were reviewed independently by two senior radiologists. Chi-square test was used for statistical analysis with the SPSS 17.0 software. In the gout group, DECT scans revealed a total of 266 areas of green-coloured voxels in 53 patients (relevance ratio 50.2% (266/530)); in the control group, 27 areas of green-coloured voxels were detected in 33 patients (relevance ratio 8.2% (27/330)), the differences had statistical significance (Pgreen-coloured voxels were detected only in the nail groove in 8 patients which compared with 2 the control group, the differences had statistical significance (Ptechnology can detect green-coloured voxels of monosodium urate in the toenails, with a great potential in clinical diagnosis.

  10. Predictive and prognostic value of 18F-DOPA PET/CT in patients affected by recurrent medullary carcinoma of the thyroid.

    Science.gov (United States)

    Caobelli, Federico; Chiaravalloti, Agostino; Evangelista, Laura; Saladini, Giorgio; Schillaci, Orazio; Vadrucci, Manuela; Scalorbi, Federica; Donner, Davide; Alongi, Pierpaolo

    2017-10-06

    Medullary thyroid carcinoma (MTC) is a malignancy accounting for about 5-8% of thyroid cancers. Serum calcitonin and carcinoembryonic antigen (CEA) levels are widely used to monitor disease progression. However, prognostic factors able to predict outcomes are highly desirable. We, therefore, aimed to assess the prognostic role of (18)F-DOPA PET/CT in patients with recurrent MTC. 60 patients (mean age 64 ± 13 years, range 44-82) with recurrent MTC were eligible from a multicenter database. All patients underwent a restaging (18)F-DOPA PET/CT, performed at least 6 months after surgery. CEA/calcitonin levels, local recurrences, nodal involvement and metastases at PET/CT were recorded. SUVmax, SUVmean (also normalized to mediastinal uptake) and metabolic tumor volume were automatically calculated for each lesion, by placing a volume of interest around the lesion with 40% of peak activity as threshold for the automatic contouring. The patients were clinically and radiologically followed up for 21 ± 11 months. Rate of progression-free survival (PFS), disease-specific survival (DSS) and incremental prognostic value of (18)F-DOPA PET/CT over conventional imaging modalities were assessed by Kaplan-Meier curves and Log-Rank test. Cox regression univariate and multivariate analyses were performed for assessing predictors of prognosis. (18)F-DOPA PET/CT showed abnormal findings in 27 patients (45%) and resulted unremarkable in 33 (55%). PFS was significantly longer in patients with an unremarkable PET/CT scan (p = 0.018). Similarly, an unremarkable PET/CT study was associated with a significantly longer DSS (p = 0.04). (18)F-DOPA PET/CT added prognostic value over other imaging modalities both for PFS and for DSS (p PET parameters nor clinical or laboratory data were predictive of a worse PFS and DSS in patients with recurrent MTC. (18)F-DOPA PET/CT scan has an important prognostic value in predicting disease progression and mortality rate.

  11. Comparison of application value between spiral CT and DR plain film in diagnosis of acetabulum fracture%对比螺旋 CT 与 DR 平片在髋臼骨折诊断中的应用价值

    Institute of Scientific and Technical Information of China (English)

    刘金全; 海忠; 崔凌; 郭锐

    2015-01-01

    目的:对比螺旋 CT 与 DR 平片在髋臼骨折诊断中的应用价值。方法58例髋臼骨折患者作为研究对象。所有患者均经手术证实为髋臼骨折,术前行螺旋 CT 与 DR 摄影,其中螺旋 CT 采用多平面重建(MPR)、三维表面重建(SSD)、容积重建(VR)等三维重建技术进行图像后处理,对比两种检查方案的诊断结果。结果CT 确诊髋臼骨折55例,高疑骨折3例, DR 确诊骨折42例,高疑8例,无骨折8例,两组确诊结果比较,差异有统计学意义(P<0.05);CT 诊断准确率更高。结论螺旋 CT 三维重建技术具有扫描快速、成像清晰的特点,在髋臼骨折诊断中具有重要的应用价值,较常规 DR 平片具有更高的确诊率,同时可有效评估患者骨折病情,为手术治疗方案提供指导。%Objective To compare the application value between spiral CT and DR plain film in diagnosis of acetabulum fracture. Methods There were 58 patients with acetabulum fracture as study subjects, and they were all diagnosed by operation. They received spiral CT and DR filming before operation. 3D reconstruction by multiple planar reconstruction (MPR), surface shading display (SSD), and volume reconstruction (VR) were applied for image postprocessing in spiral CT. Diagnosis results of the two examination methods were compared. Results CT showed 55 diagnosed acetabulum fracture cases and 3 highly suspected fracture cases. DR showed 42 diagnosed fracture cases, 8 highly suspected cases, and 8 cases without fracture. The difference between diagnosis results of the two groups had statistical significance (P<0.05). CT provided more accuracy in diagnosis. Conclusion Spiral CT 3D reconstruction method has advantages of quick scanning and clear imaging, and it contains important application value in diagnosis of acetabulum fracture. It provides higher diagnosis rate than common DR plain film with effective assessment of fracture condition, and it can

  12. Prospective ECG-triggered coronary CT angiography: clinical value of noise-based tube current reduction method with iterative reconstruction.

    Directory of Open Access Journals (Sweden)

    Junlin Shen

    Full Text Available OBJECTIVES: To evaluate the clinical value of noise-based tube current reduction method with iterative reconstruction for obtaining consistent image quality with dose optimization in prospective electrocardiogram (ECG-triggered coronary CT angiography (CCTA. MATERIALS AND METHODS: We performed a prospective randomized study evaluating 338 patients undergoing CCTA with prospective ECG-triggering. Patients were randomly assigned to fixed tube current with filtered back projection (Group 1, n = 113, noise-based tube current with filtered back projection (Group 2, n = 109 or with iterative reconstruction (Group 3, n = 116. Tube voltage was fixed at 120 kV. Qualitative image quality was rated on a 5-point scale (1 = impaired, to 5 = excellent, with 3-5 defined as diagnostic. Image noise and signal intensity were measured; signal-to-noise ratio was calculated; radiation dose parameters were recorded. Statistical analyses included one-way analysis of variance, chi-square test, Kruskal-Wallis test and multivariable linear regression. RESULTS: Image noise was maintained at the target value of 35HU with small interquartile range for Group 2 (35.00-35.03HU and Group 3 (34.99-35.02HU, while from 28.73 to 37.87HU for Group 1. All images in the three groups were acceptable for diagnosis. A relative 20% and 51% reduction in effective dose for Group 2 (2.9 mSv and Group 3 (1.8 mSv were achieved compared with Group 1 (3.7 mSv. After adjustment for scan characteristics, iterative reconstruction was associated with 26% reduction in effective dose. CONCLUSION: Noise-based tube current reduction method with iterative reconstruction maintains image noise precisely at the desired level and achieves consistent image quality. Meanwhile, effective dose can be reduced by more than 50%.

  13. 18F-Fluorodeoxyglucose Positron Emission Tomography/CT Scan Findings for Ductal Carcinomas of Breast: Association of Standardized Uptake Value and Histological Findings

    Energy Technology Data Exchange (ETDEWEB)

    Bae, So Young; Lee, Eun Hye [Dept. of Radiology, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Park, Jung Mi [Dept. of Nuclear Medicine, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Kwak, Jeong Ja [Dept. of Pathology, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of)

    2012-02-15

    To evaluate the factors associated with variations in 18F-fluorodeoxyglucose positron emission tomography/CT (18F-FDG PET/CT) uptake in ductal carcinomas of the breast. We enrolled 216 ductal carcinoma cases that underwent 18F-FDG PET/CT. We evaluated the positivity and measured peak standardized uptake value (pSUV) of lesions that underwent 18F-FDG PET/CT. We analyzed the correlation between pSUV and invasiveness, lesion size, and the histologic factors of invasive ductal carcinoma (IDC). In the 18F-FDG PET/CT of ductal carcinomas, sensitivity was 90.2%, positive and negative predictive values were 99.5% and 25.0%, respectively. In ductal carcinoma in situ (DCIS) and IDC, the sensitivities were 68.8% and 92.0%, respectively. The mean pSUV of true positive (TP) DCIS and IDC were 2.6 and 5.1 (p < 0.05), respectively, whereas the false negative (FN) were 1.3 and 1.2 (p > 0.05), respectively, and that of false positive (FP) and true negative (TN) lesions were 2.2 and 0.9, respectively. The mean size of TP DCIS and IDC were 4.5 cm and 2.7 cm (p < 0.05), respectively, whereas the mean size of FN DCIS and IDC were 1.5 cm and 1.4 cm (p > 0.05), respectively, and that of FP and TN lesions were 1.8 cm and 1.2 cm respectively. Among the histological factors affecting IDC, mitosis showed the best correlation with pSUV (rho = 0.5). For 18F-FDG PET/CT of ductal carcinomas, the positive predictive value was 99.5% and the FN rate was 9.7%. False negative factors included DCIS and an IDC < 1.5 cm, whereas mitosis was the TP factor.

  14. Valuation of Green Walls and Green Roofs as Soundscape Measures: Including Monetised Amenity Values Together with Noise-attenuation Values in a Cost-benefit Analysis of a Green Wall Affecting Courtyards

    Directory of Open Access Journals (Sweden)

    Jian Kang

    2012-10-01

    Full Text Available Economic unit values of soundscape/acoustic effects have been based on changes in the number of annoyed persons or on decibel changes. The normal procedure has been the application of these unit values to noise-attenuation measures affecting the noisier façade of a dwelling. Novel modular vegetation-based soundscape measures, so-called green walls, might be relevant for both noisy and quieter areas. Moreover, their benefits will comprise noise attenuation as well as non-acoustic amenity effects. One challenge is to integrate the results of some decades of non-acoustic research on the amenity value of urban greenery into design of the urban sound environment, and incorporate these non-acoustic properties in the overall economic assessment of noise control and overall sound environment improvement measures. Monetised unit values for green walls have been included in two alternative cases, or demonstration projects, of covering the entrances to blocks of flats with a green wall. Since these measures improve the noise environment on the quiet side of the dwellings and courtyards, not the most exposed façade, adjustment factors to the nominal quiet side decibel reductions to arrive at an estimate of the equivalent overall acoustic improvement have been applied. A cost-benefit analysis of the green wall case indicates that this measure is economically promising, when valuing the noise attenuation in the quieter area and adding the amenity/aesthetic value of the green wall.

  15. Valuation of green walls and green roofs as soundscape measures: including monetised amenity values together with noise-attenuation values in a cost-benefit analysis of a green wall affecting courtyards.

    Science.gov (United States)

    Veisten, Knut; Smyrnova, Yuliya; Klæboe, Ronny; Hornikx, Maarten; Mosslemi, Marjan; Kang, Jian

    2012-10-24

    Economic unit values of soundscape/acoustic effects have been based on changes in the number of annoyed persons or on decibel changes. The normal procedure has been the application of these unit values to noise-attenuation measures affecting the noisier façade of a dwelling. Novel modular vegetation-based soundscape measures, so-called green walls, might be relevant for both noisy and quieter areas. Moreover, their benefits will comprise noise attenuation as well as non-acoustic amenity effects. One challenge is to integrate the results of some decades of non-acoustic research on the amenity value of urban greenery into design of the urban sound environment, and incorporate these non-acoustic properties in the overall economic assessment of noise control and overall sound environment improvement measures. Monetised unit values for green walls have been included in two alternative cases, or demonstration projects, of covering the entrances to blocks of flats with a green wall. Since these measures improve the noise environment on the quiet side of the dwellings and courtyards, not the most exposed façade, adjustment factors to the nominal quiet side decibel reductions to arrive at an estimate of the equivalent overall acoustic improvement have been applied. A cost-benefit analysis of the green wall case indicates that this measure is economically promising, when valuing the noise attenuation in the quieter area and adding the amenity/aesthetic value of the green wall.

  16. Predictive value of {sup 18}F-FDG PET/CT in restaging patients affected by ovarian carcinoma: a multicentre study

    Energy Technology Data Exchange (ETDEWEB)

    Caobelli, Federico [Medizinische Hochschule Hannover, Klinik fuer Nuklearmedizin, Hanover (Germany); Alongi, Pierpaolo [University of Milano-Bicocca, Nuclear Medicine Unit, Milan (Italy); IRCSS San Raffaele Scientific Institute, Nuclear Medicine Department, Milan (Italy); Evangelista, Laura; Saladini, Giorgio [Veneto Institute of Oncology IOV - IRCCS, Radiotherapy and Nuclear Medicine Unit, Padua (Italy); Picchio, Maria [IRCSS San Raffaele Scientific Institute, Nuclear Medicine Department, Milan (Italy); Rensi, Marco; Geatti, Onelio [Hospital of Udine, Nuclear Medicine Department, Udine (Italy); Castello, Angelo; Laghai, Iashar [University of Florence, Nuclear Medicine Department, Florence (Italy); Popescu, Cristina E. [Niguarda Ca' Granda Hospital, Nuclear Medicine Department, Milan (Italy); Dolci, Carlotta; Crivellaro, Cinzia [University of Milan-Bicocca, Nuclear Medicine Department, San Gerardo Hospital, Tecnomed Foundation, Milan (Italy); Seghezzi, Silvia [Hospital of Treviglio, Nuclear Medicine Department, Treviglio, Bergamo (Italy); Kirienko, Margarita [University of Milano-Bicocca, Nuclear Medicine Unit, Milan (Italy); De Biasi, Vincenzo [Nuclear Medicine Department, Arcispedale Santa Maria Nuova, Reggio Emilia (Italy); Cocciolillo, Fabrizio [Catholic University of the Sacred Heart, Nuclear Medicine Department, Rome (Italy); Quartuccio, Natale [University of Messina, Nuclear Medicine Unit, Department of Biomedical Sciences and of Morphological and Functional Images, Messina (Italy); Collaboration: Young AIMN Working Group

    2016-03-15

    Ovarian cancer is the eighth most common malignancy among women and has a high mortality rate. Prognostic factors able to drive an effective therapy are essential. {sup 18}F-Fluoro-2-deoxyglucose positron emission tomography/computed tomography ({sup 18}F-FDG PET/CT) has been investigated in patients with epithelial ovarian cancer and showed promise in diagnosing, staging, detecting recurrent lesions and monitoring treatment response. Conversely, its prognostic role remains unclear. We aimed at assessing the prognostic value of {sup 18}F-FDG PET/CT performed in the restaging process in a multicentre study. We evaluated 168 patients affected by ovarian carcinoma, who underwent a restaging {sup 18}F-FDG PET/CT. The presence of local recurrences, lymph node involvement and distant metastasis was recorded as well as lesion dimensions, maximum and mean standardized uptake values (SUV{sub max} and SUV{sub mean}, respectively). Progression-free survival (PFS) and overall survival (OS) at 3 and 4 years were computed by using Kaplan-Meier curves. Increased odds ratio was assessed using Cox regression analysis testing all lesion parameters measured by PET/CT. PFS was significantly longer in patients with a negative than a positive restaging PET/CT study (3- and 4-year PFS 64 and 53 % vs 23 and 12 %, respectively; p < 0.001). Similarly, a negative study was associated with a significantly higher OS rate after 4 years of follow-up (67 vs 25 % in negative and positive groups, respectively; p < 0.001). Lymph node or distant involvement were also independently associated with an increased risk of disease progression [hazard ratio (HR) 1.6 and 2.2, respectively; p = 0.003]. Moreover, PET/CT showed an incremental prognostic value compared to the International Federation of Gynecology and Obstetrics (FIGO) staging system. In the analysis of patient subsets, individuals with the same FIGO stage I-II but with negative PET had a significantly better 4-year OS than patients with low

  17. Current Roles and Future Applications of Cardiac CT: Risk Stratification of Coronary Artery Disease

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yeonyee Elizabeth [Department of Cardiology, Cardiovascular Center, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Lim, Tae-Hwan [Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of)

    2014-07-01

    Cardiac computed tomography (CT) has emerged as a noninvasive modality for the assessment of coronary artery disease (CAD), and has been rapidly integrated into clinical cares. CT has changed the traditional risk stratification based on clinical risk to image-based identification of patient risk. Cardiac CT, including coronary artery calcium score and coronary CT angiography, can provide prognostic information and is expected to improve risk stratification of CAD. Currently used conventional cardiac CT, provides accurate anatomic information but not functional significance of CAD, and it may not be sufficient to guide treatments such as revascularization. Recently, myocardial CT perfusion imaging, intracoronary luminal attenuation gradient, and CT-derived computed fractional flow reserve were developed to combine anatomical and functional data. Although at present, the diagnostic and prognostic value of these novel technologies needs to be evaluated further, it is expected that all-in-one cardiac CT can guide treatment and improve patient outcomes in the near future.

  18. Predicting factors for conversion from fluoroscopy guided Percutaneous transthoracic needle biopsy to cone-beam CT guided Percutaneous transthoracic needle biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Ji; Han, Young Min; Jin, Gong Yong; Song, Ji Soo [Chonbuk National Univ., Jeonju (Korea, Republic of)

    2015-10-15

    To evaluate the predicting factors for conversion from fluoroscopy guided percutaneous transthoracic needle biopsy (PTNB) to cone-beam CT guided PTNB. From January 2011 to December 2012, we retrospectively identified 38 patients who underwent cone-beam CT guided PTNB with solid pulmonary lesions, and 76 patients who underwent fluoroscopy guided PTNB were matched to the patients who underwent cone-beam CT guided PTNB for age, sex, and lesion location. We evaluated predicting factors such as, long-axis diameter, short-axis diameter, anterior-posterior diameter, and CT attenuation value of the solid pulmonary lesion affecting conversion from fluoroscopy guided PTNB to cone-beam CT guided PTNB. Pearson χ{sup 2} test, Fisher exact test, and independent t test were used in statistical analyses; in addition, we also used receiver operating characteristics curve to find the proper cut-off values affecting the conversion to cone-beam CT guided PTNB. Short-axis, long-axis, anterior-posterior diameter and CT attenuation value of the solid pulmonary lesion in patients who underwent fluoroscopy guided PTNB were 2.70 ± 1.57 cm, 3.40 ± 1.92 cm, 3.06 ± 1.81 cm, and 35.67 ± 15.70 Hounsfield unit (HU), respectively. Short-axis, long-axis, anterior-posterior diameter and CT attenuation value of the solid pulmonary lesion in patients who underwent cone-beam CT guided PTNB were 1.60 ± 1.30 cm, 2.20 ± 1.45 cm, 1.91 ± 1.99 cm, and 18.32 ± 23.11 HU, respectively. Short-axis, long-axis, anterior-posterior diameter, and CT attenuation value showed a significantly different mean value between the 2 groups (p = 0.001, p < 0.001, p = 0.003, p < 0.001, respectively). Odd ratios of CT attenuation value and short-axis diameter of the solid pulmonary lesion were 0.952 and 0.618, respectively. Proper cut-off values affecting the conversion to cone-beam CT guided PTNB were 1.65 cm (sensitivity 68.4%, specificity 71.1%) in short-axis diameter and 29.50 HU (sensitivity 65.8%, specificity 65

  19. Excess attenuation of an acoustic beam by turbulence.

    Science.gov (United States)

    Pan, Naixian

    2003-12-01

    A theory based on the concept of a spatial sinusoidal diffraction grating is presented for the estimation of the excess attenuation in an acoustic beam. The equation of the excess attenuation coefficient shows that the excess attenuation of acoustic beam not only depends on the turbulence but also depends on the application parameters such as the beam width, the beam orientation and whether for forward propagation or back scatter propagation. Analysis shows that the excess attenuation appears to have a frequency dependence of cube-root. The expression for the excess attenuation coefficient has been used in the estimations of the temperature structure coefficient, C(T)2, in sodar sounding. The correction of C(T)2 values for excess attenuation reduces their errors greatly. Published profiles of temperature structure coefficient and the velocity structure coefficient in convective conditions are used to test our theory, which is compared with the theory by Brown and Clifford. The excess attenuation due to scattering from turbulence and atmospheric absorption are both taken into account in sodar data processing for deducing the contribution of the lower atmosphere to seeing, which is the sharpness of a telescope image determined by the degree of turbulence in the Earth's atmosphere. The comparison between the contributions of the lowest 300-m layer to seeing with that of the whole atmosphere supports the reasonableness of our estimation of excess attenuation.

  20. The diagnostic value of contrast-enhanced CT in Acute bilateral renal cortical necrosis: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Pil Youb; Lee, Su Han; Lee, Woo Dong [Masan Samsung General Hospital, Seoul (Korea, Republic of)

    1996-11-01

    Acute renal cortical necrosis in which there is destruction of the renal cortex and sparing of the renal medulla, is a relatively rare cause of acute renal failure. A definitive diagnosis of acute renal cortical necrosis is based on renal biopsy, but on CT(computed tomography) the rather specific contrast-enhanced appearance of acute renal cortical necrosis has been described. As renal biopsy is not available, contrast-enhanced CT is a useful, noninvasive investigate modality for the early diagnosis of acute renal cortical necrosis. We report the characteristic CT findings of acute renal cortical necrosis in a patient with acute renal failure following an operation for abdominal trauma.

  1. Nodular lesions seen on CTAP not on conventional CT in known hepatocellular carcinoma (HCC) patients: positive predictive value for HCC or precusor of HCC

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jae Chun; Lee, Yong Woo; Hwang, Mi Soo [College of Medicine, Yeungnam University, Daegu (Korea, Republic of)

    1995-01-15

    To evaluate intrahepatic nodular lesions detected on CTAP but not on conventional contrast CT in regard to its relationship with satellite nodules or borderline malignancies. From June 1991 to March 1994, CTAP was undertaken in 132 cases with confirmed hepatocellular carcinoma (HCC), or which 35 cases having 82 lesions were suitable for analysis (excluding the cases which had no follow-up studies, showed segmental abnormal portal perfusion, no additional lesions and, or inumerable lesions). The CTAP findings were compared with those on artery dominant imaging studies (angiography, DSA, bolus dynamic CT, arterial CT, Lipiodol CT) taken during the same period (to confirm the presence of lesions) and the findings on follow-up imaging studies (to assess the development of malignancy). Arterial vascularity was identified in 35 of 82 lesions (42.7%) on arterial dominant imaging studies. Development into malignancy was identified on follow-up imaging studies in 25 of remained 47 lesions (53.2%). The total positive predictive value of nodules on CTAP was 73.2% (35 + 25/82), but the predictive value for HCC by follow-up only was 53.2%. Given the difficulties in detecting intranodular arterial flow and the short follow-up duration in many patients, the actual positive value might be higher.

  2. Assessment of the diagnostic value of dual-energy CT and MRI in the detection of iatrogenically induced injuries of anterior cruciate ligament in a porcine model

    Energy Technology Data Exchange (ETDEWEB)

    Fickert, S.; Niks, M.; Lehmann, L. [University Medical Center Mannheim, Center of Orthopaedics and Traumatology, Mannheim (Germany); Dinter, D.J.; Hammer, M.; Weckbach, S.; Schoenberg, S.O.; Jochum, S. [University Medical Center Mannheim, Department of Clinical Radiology and Nuclear Medicine, Mannheim (Germany)

    2013-03-15

    Magnetic resonance imaging (MRI) is the standard of reference for the non-invasive evaluation of ligament injuries of the knee. The development of dual-energy CT (DE-CT) made it possible to differentiate between tissues of different density by two simultaneous CT measurements with different tube voltages. This approach enables DE-CT to discriminate ligament structures without intra-articular contrast media injection. The aims of this study were on the one hand to determine the delineation of the anterior cruciate ligament (ACL) and on the other hand to assess the diagnostic value of DE-CT and MRI in the detection of iatrogenically induced injury of the ACL in a porcine knee joint model. Twenty porcine hind legs, which were placed in a preformed cast in order to achieve a standardized position, were scanned using DE-CT. Thereafter, a 1.5-T MRI using a standard protocol was performed. The imaging procedures were repeated with the same parameters after inducing defined lesions (total or partial incision) on the ACL arthroscopically. After post-processing, two radiologists and two orthopedic surgeons first analyzed the delineation of the ACL and then, using a consensus approach, the iatrogenically induced lesions. The result of the arthrotomy was defined as the standard of reference. The ACL could be visualized both on DE-CT and MRI in 100% of the cases. As for the MRI, the sensitivity and specificity of detecting the cruciate ligament lesion respectively compared with the defined arthrotomy was 66.7% and 78.6% for intact cruciate ligaments, 100% and 75% in the case of a complete lesion, 33.3% and 78.6% for lesions of the anteromedial bundle, and 0% and 100% for lesions of the posterolateral bundle. In comparison, DE-CT demonstrated a sensitivity and specificity of 66.7% and 71.4% in the case of intact cruciate ligaments, 75% and 68.8% in the case of completely discontinued ACLs, 0% and 92.9% in the case of lesions of the anteromedial bundle, and 25% and 87.5% in the

  3. Trabectedin in Advanced High-Grade Uterine Leiomyosarcoma: A Case Report Illustrating the Value of18FDG-PET-CT in Assessing Treatment Response

    Directory of Open Access Journals (Sweden)

    M.J. Payne

    2014-02-01

    Full Text Available We report the case of a 60-year-old woman with metastatic high-grade uterine leiomyosarcoma who achieved a delayed response to second-line therapy with the marine-derived drug trabectedin (Yondelis®, PharmaMar. We used 2-deoxy-2-[18F] fluorodeoxyglucose (FDG-positron emission tomography (PET-CT imaging as a tool for response monitoring in parallel with conventional re-staging according to Response Evaluation Criteria in Solid Tumours (RECIST using computed tomography (CT. We illustrate the role of serial 18FDG-PET-CT imaging in the functional assessment of tumour response. Three cycles after commencement of trabectedin treatment, a reduction of the maximum standardized uptake value (SUVmax of the solid component of the pelvic mass was observed, indicating a cystic or necrotic response in the tumour to trabectedin. After 7 cycles of treatment, on 18FDG-PET-CT there was clear evidence of ongoing disease improvement: the solid pelvic components were at worst stable, with an unchanged SUVmax, and possibly marginally reduced in size, while the pulmonary metastases had further reduced in size and become FDG negative; the bony metastases were stable. After a total of 13 cycles of treatment, administered over 13 months, the patient showed signs of progression on an 18FDG-PET-CT scan. The safety profile of trabectedin remained manageable, showing no evidence of cumulative toxicity and being associated with a preserved quality of life. This report illustrates potential limitations of RECIST in response assessments and the critical role of serial 18FDG-PET-CT imaging in assessing response to trabectedin treatment. Therefore, we propose that 18FDG-PET-CT may improve the assessment of response to trabectedin in selected patients.

  4. Simultaneous reconstruction of emission activity and attenuation coefficient distribution from TOF data, acquired with external transmission source.

    Science.gov (United States)

    Panin, V Y; Aykac, M; Casey, M E

    2013-06-07

    The simultaneous PET data reconstruction of emission activity and attenuation coefficient distribution is presented, where the attenuation image is constrained by exploiting an external transmission source. Data are acquired in time-of-flight (TOF) mode, allowing in principle for separation of emission and transmission data. Nevertheless, here all data are reconstructed at once, eliminating the need to trace the position of the transmission source in sinogram space. Contamination of emission data by the transmission source and vice versa is naturally modeled. Attenuated emission activity data also provide additional information about object attenuation coefficient values. The algorithm alternates between attenuation and emission activity image updates. We also proposed a method of estimation of spatial scatter distribution from the transmission source by incorporating knowledge about the expected range of attenuation map values. The reconstruction of experimental data from the Siemens mCT scanner suggests that simultaneous reconstruction improves attenuation map image quality, as compared to when data are separated. In the presented example, the attenuation map image noise was reduced and non-uniformity artifacts that occurred due to scatter estimation were suppressed. On the other hand, the use of transmission data stabilizes attenuation coefficient distribution reconstruction from TOF emission data alone. The example of improving emission images by refining a CT-based patient attenuation map is presented, revealing potential benefits of simultaneous CT and PET data reconstruction.

  5. 18F-FDG PET/CT 和 MRI 对恶性肿瘤诊断价值的比较%Comparison of diagnosis value between 18F-FDG PET/CT and MRI in malignant tumor

    Institute of Scientific and Technical Information of China (English)

    邹惠峰; 潘律德; 章斌; 吴翼伟

    2014-01-01

    目的:比较18f-fdG Pet/ct 和 Mri 在恶性肿瘤诊断中的作用。方法选择34例怀疑恶性肿瘤的患者作为研究对象,一周内进行18f-fdG Pet/ct、Mri 检查及得到病理结果。以病理结果为金标准,计算18f-fdG Pet/ct 和 Mri 诊断恶性肿瘤的灵敏度、特异度及准确率。结果组织病理学证实在34例患者中,恶性肿瘤26例,良性病变8例,Pet/ct 诊断恶性肿瘤的灵敏度、特异度、准确率分别为92.3%、50.0%和82.4%,Mri 灵敏度、特异度、准确率分别为76.9%、87.5%和79.4%。Pet/ct 诊断准确度要高于 Mri,但两者之间差异无统计学意义(χ2=0.092,P>0.05).结论在探测恶性肿瘤诊断准确性方面,18f-fdG Pet/ct 和 Mri 均有较高的价值,两种诊断方法有各自的优缺点,应将两者结合起来,以提高恶性肿瘤诊断的准确率。%Objective to compare the effects between 18f-fdG Pet/ct and Mri in diagnosis of malignant tumor.Methods 34 patients with suspicious malignant tumor were selected,18f-fdG Pet/ct and Mri scanning were performed and their pathological results were gotten within one week.the sensitivities,specificities and accuracies of PET/CT and MRI in detecting malignant tumor were calculated using surgery or biopsy results as diagnostic golden standard.Results 26 malignant tumors And 8 benign lesions of the 34 patients were proven histologically after suigery or biopsy.The sensitivity,specificity and accuracy value obtained by Pet/ct were 92.3%、50.0% and 82.4% ,respectively ,and they were 76.9%、87.5%和 79.4% for Mri.the accuracy of PET/CT was a little higher than that of MRI,but there was no significant difference between them(χ2=0.092,P>0.05). Conclusion in the detection of malignant tumors accuracy ,Pet/ct and Mri have a higher value.the two diagnostic methods have their own advantages and disadvantages,we should combine the two,in order to enhance the accuracy of diagnosis of malignant tumor.

  6. 类风湿性关节炎合并肺间质病变的 CT 诊断价值研究%Diagnostic Value of CT in interstitial lung disease of Rheumatoid Arthritis

    Institute of Scientific and Technical Information of China (English)

    黄振强

    2012-01-01

      Objective: To explore the diagnostic value of CT in ininterstitial lung disease of Rheumatoid Arthritis(RA).Methods: Retrospectively analyzed the 60 cases of patients in ininterstitial lung disease of Rheumatoid Arthritis(RA) in my hospital from 2009 July to 2012 July.Grouped and compared the clinical manifestations and detection of lung lesions of Chest x-ray film and CT examination. Results: Among 30 cases, the most manifestations of chest X-ray wer thest pulmonary markings were in-creased but the changes of pulmonary interstitium and pleura were not obvious.The detection rate of lung disease is 56.67%. Among other 30 cases,the manifestations of CT examination changed of interstitium and pleura pathological.The detection rate of lung disease is 96.66%.There is significant differences Between two groups(P<0.05).Conclusion:The application of CT examination can significantly improve the detection rate of Rheumatoid Arthritis(RA) lung disease and help to determine the stage of RA and to estimate the prognosis in patients with RA.%  目的:探讨 CT 对类风湿性关节炎(RA)合并肺间质病变的诊断价值.方法:对我院2009年7月至2012年7月的60例 RA 合并肺间质病变患者进行回顾性分析.分组比较 X 线胸片和 CT 检查的临床表现及对肺部病变的检出率.结果:30例患者 X 线胸片主要表现为:两肺纹理增粗,肺间质及胸膜改变不明显,对肺部病变检出率为56.67%;另30例患者 CT 扫描检查表现为:部分肺间质改变及胸膜病变,对肺部病变检出率为96.66%,两者具显著性差异(P<0.05).结论:应用 CT 检查可以明显提高类风湿性关节炎(RA)肺部病变的检出率,以早期了解 RA 浸润肺部的程度及估计预后.

  7. CT findings of orbital langerhans cell histiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Gina; Yoon, Hye Kyung; Han, Bokyung Kim; Kim, Kyeong Ah; Choo, In Wook [Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul (Korea, Republic of)

    2000-05-01

    To evaluate the CT findings in patients with Langerhans cell histiocytosis (LCH) involving the orbit. Orbital CT scans of six children with pathologically proven LCH were retrospectively analyzed. Follow-up CT (n=3D5) and MR (n=3D1) imaging findings were also reviewed. Initial CT scans revealed varying degree of bone destruction with soft-tissue masses, and on nonenhanced images the mean attenuation value was 44 Hounsfield units (HU). All masses showed mild to moderate enhancement with a mean attenuation value of 74 HU. The bony margins abutting onto soft tissue masses were irregular but clearly demarcated. No evidence of calcification or periosteal reaction was noted. Suprasellar mass and rib involvement was noted in one patient and hepatosplenomegaly in two. Follow-up CT and MR images showed that the soft tissue masses were almost completely resolved, with bone remodeling and reossification. A soft tissue mass with irregular but clearly demarcated bone destruction is thought to be a characteristic finding of LCH involving the orbit. Follow-up images after treatment showed bone remodeling and reossification. (author)

  8. Clinical value of SPECT/CT for evaluation of patients with painful knees after total knee arthroplasty- a new dimension of diagnostics?

    Directory of Open Access Journals (Sweden)

    Rasch Helmut

    2011-02-01

    Full Text Available Abstract Background The purpose of our study was to evaluate the clinical value of hybrid SPECT/CT for the assessment of patients with painful total knee arthroplasty (TKA. Methods Twenty-three painful knees in patients following primary TKA were assessed using Tc-99m-HDP-SPECT/CT. Rotational, sagittal and coronal position of the TKA was assessed on 3D-CT reconstructions. The level of the SPECT-tracer uptake (0-10 and its anatomical distribution was mapped using a validated localization scheme. Univariate analysis (Wilcoxon-Mann-Whitney, Spearmean`s-rho test, p Results SPECT/CT imaging changed the suspected diagnosis and the proposed treatment in 19/23 (83% knees. Progression of patellofemoral OA (n = 11, loosening of the tibial (n = 3 and loosening of the femoral component (n = 2 were identified as the leading causes of pain after TKA. Patients with externally rotated tibial trays showed higher tracer uptake in the medial patellar facet (p = 0.049 and in the femur (p = 0.051. Patients with knee pain due to patellofemoral OA showed significantly higher tracer uptake in the patella than others (p Conclusions SPECT/CT was very helpful in establishing the diagnosis and guiding subsequent management in patients with painful knees after TKA, particularly in patients with patellofemoral problems and malpositioned or loose TKA.

  9. Does the presence of tumor-induced cortical bone destruction at CT have any prognostic value in newly diagnosed diffuse large B-cell lymphoma?

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Hugo J.A.; Nievelstein, Rutger A.J.; Kwee, Thomas C. [University Medical Center Utrecht, Department of Radiology and Nuclear Medicine, Utrecht (Netherlands); Klerk, John M.H. de [Meander Medical Center, Department of Nuclear Medicine, Amersfoort (Netherlands); Fijnheer, Rob [Meander Medical Center, Department of Hematology, Amersfoort (Netherlands); Heggelman, Ben G.F. [Meander Medical Center, Department of Radiology, Amersfoort (Netherlands); Dubois, Stefan V. [Meander Medical Center, Department of Pathology, Amersfoort (Netherlands)

    2015-05-01

    To determine the prognostic value of tumor-induced cortical bone destruction at computed tomography (CT) in newly diagnosed diffuse large B-cell lymphoma (DLBCL). This retrospective study included 105 patients with newly diagnosed DLBCL who had undergone CT and bone marrow biopsy (BMB) before R-CHOP (rituximab, cyclophosphamide, hydroxydaunorubicin, Oncovin, and prednisolone) chemo-immunotherapy. Cox regression analyses were used to determine the associations of cortical bone status at CT (absence vs. presence of tumor-induced cortical bone destruction), BMB findings (negative vs. positive for lymphomatous involvement), and dichotomized National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) strata (low risk vs. high risk) with progression-free survival (PFS) and overall survival (OS). Univariate Cox regression analysis indicated that cortical bone status at CT was no significant predictor of either PFS or OS (p = 0.358 and p = 0.560, respectively), whereas BMB findings (p = 0.002 and p = 0.013, respectively) and dichotomized NCCN-IPI risk strata (p = 0.002 and p = 0.003, respectively) were significant predictors of both PFS and OS. In the multivariate Cox proportional hazards model, only the dichotomized NCCN-IPI score was an independent predictive factor of PFS and OS (p = 0.004 and p = 0.003, respectively). The presence of tumor-induced cortical bone destruction at CT was not found to have any prognostic implications in newly diagnosed DLBCL. (orig.)

  10. Respiratory gated PET/CT in a European multicentre retrospective study: added diagnostic value in detection and characterization of lung lesions

    Energy Technology Data Exchange (ETDEWEB)

    Guerra, Luca; Elisei, Federica [San Gerardo Hospital, Nuclear Medicine, Monza (Italy); De Ponti, Elena [San Gerardo Hospital, Medical Physics, Monza (Italy); Bettinardi, Valentino; Picchio, Maria [San Raffaele Scientific Institute, Nuclear Medicine, Milan (Italy); National Research Council, Institute for Bioimaging and Molecular Physiology, Milan (Italy); Landoni, Claudio [San Raffaele Scientific Institute, Nuclear Medicine, Milan (Italy); University of Milano-Bicocca, Milan (Italy); Gilardi, Maria Carla [San Raffaele Scientific Institute, Nuclear Medicine, Milan (Italy); National Research Council, Institute for Bioimaging and Molecular Physiology, Milan (Italy); University of Milano-Bicocca, Tecnomed Foundation, Milan (Italy); Versari, Annibale [Scientific Institute Santa Maria Nuova Hospital, Nuclear Medicine, Reggio Emilia (Italy); Fioroni, Federica [Scientific Institute Santa Maria Nuova Hospital, Medical Physics, Reggio Emilia (Italy); Dziuk, Miroslaw [Masovian PET-CT Centre, Department of Nuclear Medicine, Military Institute of Medicine, Warsaw (Poland); Koza, Magdalena [Masovian PET-CT Centre, Euromedic Diagnostic, Warsaw (Poland); Ahond-Vionnet, Renee; Collin, Bertrand [Hopital Pierre Beregovoy, Service de Medecine Nucleaire, Nevers (France); Messa, Cristina [San Gerardo Hospital, Nuclear Medicine, Monza (Italy); National Research Council, Institute for Bioimaging and Molecular Physiology, Milan (Italy); University of Milano-Bicocca, Tecnomed Foundation, Milan (Italy)

    2012-09-15

    The aim of our work is to evaluate the added diagnostic value of respiratory gated (4-D) positron emission tomography/computed tomography (PET/CT) in lung lesion detection/characterization in a large patient population of a multicentre retrospective study. The data of 155 patients (89 men, 66 women, mean age 63.9 {+-} 11.1 years) from 5 European centres and submitted to standard (3-D) and 4-D PET/CT were retrospectively analysed. Overall, 206 lung lesions were considered for the analysis (mean {+-} SD lesions dimension 14.7 {+-} 11.8 mm). Maximum standardized uptake values (SUV{sub max}) and lesion detectability were assessed for both 3-D and 4-D PET/CT studies; 3-D and 4-D PET/CT findings were compared to clinical follow-up as standard reference. Mean {+-} SD 3-D and 4-D SUV{sub max} values were 5.2 {+-} 5.1 and 6.8 {+-} 6.1 (p < 0.0001), respectively, with an average percentage increase of 30.8 %. In 3-D PET/CT, 86 of 206 (41.7 %) lesions were considered positive, 70 of 206 (34 %) negative and 50 of 206 (24.3 %) equivocal, while in 4-D PET/CT 117 of 206 (56.8 %) lesions were defined as positive, 80 of 206 (38.8 %) negative and 9 of 206 (4.4 %) equivocal. In 34 of 50 (68 %) 3-D equivocal lesions follow-up data were available and the presence of malignancy was confirmed in 21 of 34 (61.8 %) lesions, while in 13 of 34 (38.2 %) was excluded. In 31 of these 34 controlled lesions, 20 of 34 (58.8 %) and 11 of 34 (32.4 %) were correctly classified by 4-D PET/CT as positive and negative, respectively; 3 of 34 (8.8 %) remained equivocal. With equivocal lesions classified as positive, the overall accuracy of 3-D and 4-D was 85.7 and 92.8 %, respectively, while the same figures were 80.5 and 94.2 % when equivocal lesions were classified as negative. The respiratory gated PET/CT technique is a valuable clinical tool in diagnosing lung lesions, improving quantification and confidence in reporting, reducing 3-D undetermined findings and increasing the overall accuracy in lung

  11. ADDITIONAL VALUE OF POST-THERAPY 131 I SPECT/CT IN PATIENTS WITH DIFFERENTIATED THYROID CANCER

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    Satyawati Deswal

    2017-03-01

    Full Text Available BACKGROUND Generally, it is seen that SPECT/CT images are more useful than the planar images. We compared post-therapy 131 I imaging findings on planar and SPECT/CT scans to assess the clinical utility of SPECT/CT in management of patients with differentiated thyroid cancer. MATERIALS AND METHODS Post-therapy imaging was performed at 4-7 (when 5mR/hrs. exposure rate were observed by the survey meter days after 131 I administration and all patients underwent whole-body scintigraphy and SPECT/CT scanning on the same day. A generalised McNemar 1 was used to determine to establish the agreement between planar whole-body imaging and SPECT/CT for the assignment of benign, equivocal and malignant findings. RESULTS In 44 patients, 32 of the 44 patients underwent postsurgical 131 I ablation of residual thyroid tissue and 12 of 44 patients, 2 patients were treated twice. Hence, a total of 46 scans were analysed. SPECT/CT helped to localise focal iodine uptake and characterise it as either normal or abnormal thereby reducing the need for additional imaging studies. In post-thyroidectomy patients, SPECT/CT findings affected the ATA risk classification with implications for management by changing the interval for clinical followup and the need for additional imaging and laboratory tests. Our study found an 11% change in nodal status in the postsurgical group. Change in patient management was observed in 18%. CONCLUSION SPECT/CT enabled more accurate characterisation of focal iodine accumulation in patients.

  12. Application value of CT perfusion imaging with acetazolamide challenge test in the diagnosis of chronic cerebral insufficiency

    Institute of Scientific and Technical Information of China (English)

    高轩

    2014-01-01

    Objective To explore the CT perfusion imaging with acetazolamide(ACZ)challenge test in the diagnosis of chronic cerebral insufficiency.Methods 100 patients undergoing health examination in our hospital from Aug2009 to Feb 2011 were chosen,52 patients diagnosed as chronic cerebral insufficiency were defined as the case group,and the remaining 48 cases of healthy elderly people were defined as the control group.The brain CT

  13. The added value of SPECT-CT for the identification of sentinel lymph nodes in early stage oral cancer

    Energy Technology Data Exchange (ETDEWEB)

    Toom, Inne J. den; Bree, Remco de [VU University Medical Center, Department of Otolaryngology-Head and Neck Surgery, Amsterdam (Netherlands); UMC Utrecht Cancer Center, University Medical Center, Department of Head and Neck Surgical Oncology, PO Box 85500, Utrecht (Netherlands); Schie, Annelies van; Hoekstra, Otto S. [VU University Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands); Weert, Stijn van [VU University Medical Center, Department of Otolaryngology-Head and Neck Surgery, Amsterdam (Netherlands); Karagozoglu, K.H. [VU University Medical Center/Academic Centre for Dentistry (ACTA) Amsterdam, Department of Oral and Maxillofacial Surgery/Oral Pathology, Amsterdam (Netherlands); Bloemena, Elisabeth [VU University Medical Center/Academic Centre for Dentistry (ACTA) Amsterdam, Department of Oral and Maxillofacial Surgery/Oral Pathology, Amsterdam (Netherlands); VU University Medical Center, Department of Pathology, Amsterdam (Netherlands)

    2017-06-15

    To assess the role of single-photon emission computed tomography with computed tomography (SPECT-CT) for the identification of sentinel lymph nodes (SLNs) in patients with early stage (T1-T2) oral cancer and a clinically negative neck (cN0). In addition to planar lymphoscintigraphy, SPECT-CT was performed in 66 consecutive patients with early stage oral cancer and a clinically negative neck. The addition of SPECT-CT to planar images was retrospectively analyzed for the number of additional SLNs, more precise localization of SLNs, and importance of anatomical information by a team consisting of a nuclear physician, surgeon, and investigator. Identification rate for both imaging modalities combined was 98% (65/66). SPECT-CT identified 15 additional SLNs in 14 patients (22%). In 2/15 (13%) of these additional SLNs, the only metastasis was found, resulting in an upstaging rate of 3% (2/65). In 20% of the patients with at least one positive SLN, the only positive SLN was detected due to the addition of SPECT-CT. SPECT-CT was considered to add important anatomical information in two patients (3%). In 5/65 (8%) of the patients initially scored SLNs on planar lymphoscintigrams were scored as non-SLNs when SPECT-CT was added. There were four false-negative SLN biopsy procedures in this cohort. The addition of SPECT-CT to planar lymphoscintigraphy is recommended for the identification of more (positive) SLNs and better topographical orientation for surgery in sentinel lymph node biopsy for early stage oral cancer. (orig.)

  14. Dual Energy CT (DECT Monochromatic Imaging: Added Value of Adaptive Statistical Iterative Reconstructions (ASIR in Portal Venography.

    Directory of Open Access Journals (Sweden)

    Liqin Zhao

    Full Text Available To investigate the effect of the adaptive statistical iterative reconstructions (ASIR on image quality in portal venography by dual energy CT (DECT imaging.DECT scans of 45 cirrhotic patients obtained in the portal venous phase were analyzed. Monochromatic images at 70keV were reconstructed with the following 4 ASIR percentages: 0%, 30%, 50%, and 70%. The image noise (IN (standard deviation, SD of portal vein (PV, the contrast-to-noise-ratio (CNR, and the subjective score for the sharpness of PV boundaries, and the diagnostic acceptability (DA were obtained. The IN, CNR, and the subjective scores were compared among the four ASIR groups.The IN (in HU of PV (10.05±3.14, 9.23±3.05, 8.44±2.95 and 7.83±2.90 decreased and CNR values of PV (8.04±3.32, 8.95±3.63, 9.80±4.12 and 10.74±4.73 increased with the increase in ASIR percentage (0%, 30%, 50%, and 70%, respectively, and were statistically different for the 4 ASIR groups (p<0.05. The subjective scores showed that the sharpness of portal vein boundaries (3.13±0.59, 2.82±0.44, 2.73±0.54 and 2.07±0.54 decreased with higher ASIR percentages (p<0.05. The subjective diagnostic acceptability was highest at 30% ASIR (p<0.05.30% ASIR addition in DECT portal venography could improve the 70 keV monochromatic image quality.

  15. Added diagnostic value of respiratory-gated 4D 18F-FDG PET/CT in the detection of liver lesions: a multicenter study.

    Science.gov (United States)

    Crivellaro, Cinzia; De Ponti, Elena; Elisei, Federica; Morzenti, Sabrina; Picchio, Maria; Bettinardi, Valentino; Versari, Annibale; Fioroni, Federica; Dziuk, Miroslaw; Tkaczewski, Konrad; Ahond-Vionnet, Renée; Nodari, Guillaume; Todde, Sergio; Landoni, Claudio; Guerra, Luca

    2017-08-19

    The aim of the present study was to evaluate the added diagnostic value of respiratory-gated 4D18F-FDG PET/CT in liver lesion detection and characterization in a European multicenter retrospective study. Fifty-six oncological patients (29 males and 27 females, mean age, 61.2 ± 11.2 years) from five European centers, submitted to standard 3D-PET/CT and liver 4D-PET/CT were retrospectively evaluated. Based on visual analysis, liver PET/CT findings were scored as positive, negative, or equivocal both in 3D and 4D PET/CT. The impact of 4D-PET/CT on the confidence in classifying liver lesions was assessed. PET/CT findings were compared to histology and clinical follow-up as standard reference and diagnostic accuracy was calculated for both techniques. At semi-quantitative analysis, SUVmax was calculated for each detected lesion in 3D and 4D-PET/CT. Overall, 72 liver lesions were considered for the analysis. Based on visual analysis in 3D-PET/CT, 32/72 (44.4%) lesions were considered positive, 21/72 (29.2%) negative, and 19/72 (26.4%) equivocal, while in 4D-PET/CT 48/72 (66.7%) lesions were defined positive, 23/72 (31.9%) negative, and 1/72 (1.4%) equivocal. 4D-PET/CT findings increased the confidence in lesion definition in 37/72 lesions (51.4%). Considering 3D equivocal lesions as positive, sensitivity, specificity, and accuracy were 88.9, 70.0, and 83.1%, respectively, while the same figures were 67.7, 90.0, and 73.8% if 3D equivocal findings were included as negative. 4D-PET/CT sensitivity, specificity, and accuracy were 97.8, 90.0, and 95.4%, respectively, considering equivocal lesions as positive and 95.6, 90.0, and 93.8% considering equivocal lesions as negative. The SUVmax of the liver lesions in 4D-PET (mean ± SD, 6.9 ± 3.2) was significantly higher (p < 0.001) than SUVmax in 3D-PET (mean ± SD, 5.2 ± 2.3). Respiratory-gated PET/CT technique is a valuable clinical tool in diagnosing liver lesions, reducing 3D undetermined findings, improving

  16. Preliminary discussion on the value of {sup 18}F-FDG PET/CT in the diagnosis and early staging of non-mycosis fungoides/Sézary's syndrome cutaneous malignant lymphomas

    Energy Technology Data Exchange (ETDEWEB)

    Dan, Shao, E-mail: shaodan501@outlook.com [Southern Medical University, Guangzhou, Guangdong (China); Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Qiang, Gao, E-mail: onwaykung@163.com [The First People' s Hospital of Foshan, Foshan, Guangdong (China); Shu-Xia, Wang, E-mail: wang_shuxia@outlook.com [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Chang-Hong, Liang, E-mail: cjr.lchh@vip.163.com [Department of Radiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China)

    2015-07-15

    Highlights: • We discussed the value of PET/CT in the diagnosis and early staging of non-MF/SS CML. • We calculated the sensitivity of CT and PET/CT in the diagnosis of primary skin lesions. • We calculated the value of CT and PET/CT in the diagnosis of LNs and other organs. - Abstract: Objective: To discuss the value of {sup 18}F-fluorodeoxyglucose-positron emission tomography ({sup 18}F-PET/CT) scans in the diagnosis and early staging of non-mycosis fungoides/Sézary's syndrome cutaneous malignant lymphomas (non-MF/SS CML). Materials and methods: A total of 18 cases with non-MF/SS CML, confirmed by pathology or on clinical grounds, were analyzed in this study. The sensitivity of CT and PET/CT scans in the diagnosis of primary skin lesions, as well as the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT and PET/CT scans in the diagnosis of lymph nodes (LNs) and other organs (except skin and LNs) were calculated. Results: The diagnostic sensitivity of CT and PET/CT scans in the diagnosis of primary skin lesions was 82.4% (14/17) and 100% (17/17), respectively. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT and PET/CT scans in the diagnosis of LN lesions were 55.6% (5/9), 88.9% (8/9), 72.2% (13/18), 83.3% (5/6), 66.7% (8/12), and 88.9% (8/9), 100% (9/9), 94.4% (17/18), 100% (8/8), 90.0% (9/10), respectively. The diagnostic value of the CT and PET/CT scans in the diagnosis of involvement of other organs, were 40.4% (2/5), 100% (13/13), 83.3 (15/18), 100% (2/2), 81.3% (13/16) and 80.6% (4/5), 100% (13/13), 94.4% (17/18), 100% (3/3), 92.9% (13/14), respectively. Conclusions: {sup 18}F-FDG PET/CT has high value in the diagnosis and early staging of non-MF/SS CMLs.

  17. Is There an Additional Value of {sup 11}C-Choline PET-CT to T2-weighted MRI Images in the Localization of Intraprostatic Tumor Nodules?

    Energy Technology Data Exchange (ETDEWEB)

    Van den Bergh, Laura, E-mail: laura.vandenbergh@uzleuven.be [Department of Radiation Oncology, University Hospitals Leuven, Leuven (Belgium); Koole, Michel [Department of Nuclear Medicine, University Hospitals Leuven, Leuven (Belgium); Isebaert, Sofie [Department of Radiation Oncology, University Hospitals Leuven, Leuven (Belgium); Joniau, Steven [Department of Urology, University Hospitals Leuven, Leuven (Belgium); Deroose, Christophe M. [Department of Nuclear Medicine, University Hospitals Leuven, Leuven (Belgium); Oyen, Raymond [Department of Radiology, University Hospitals Leuven, Leuven (Belgium); Lerut, Evelyne [Department of Histopathology, University Hospitals Leuven, Leuven (Belgium); Budiharto, Tom [Department of Radiation Oncology, University Hospitals Leuven, Leuven (Belgium); Mottaghy, Felix [Department of Nuclear Medicine, University Hospitals Leuven, Leuven (Belgium); Klinik fuer Nuklearmedizin, Universitaetsklinikum Aachen, Aachen (Germany); Bormans, Guy [Department of Nuclear Medicine, University Hospitals Leuven, Leuven (Belgium); Van Poppel, Hendrik [Department of Urology, University Hospitals Leuven, Leuven (Belgium); Haustermans, Karin [Department of Radiation Oncology, University Hospitals Leuven, Leuven (Belgium)

    2012-08-01

    Purpose: To investigate the additional value of {sup 11}C-choline positron emission tomography (PET)-computed tomography (CT) to T2-weighted (T2w) magnetic resonance imaging (MRI) for localization of intraprostatic tumor nodules. Methods and Materials: Forty-nine prostate cancer patients underwent T2w MRI and {sup 11}C-choline PET-CT before radical prostatectomy and extended lymphadenectomy. Tumor regions were outlined on the whole-mount histopathology sections and on the T2w MR images. Tumor localization was recorded in the basal, middle, and apical part of the prostate by means of an octant grid. To analyze {sup 11}C-choline PET-CT images, the same grid was used to calculate the standardized uptake values (SUV) per octant, after rigid registration with the T2w MR images for anatomic reference. Results: In total, 1,176 octants were analyzed. Sensitivity, specificity, and accuracy of T2w MRI were 33.5%, 94.6%, and 70.2%, respectively. For {sup 11}C-choline PET-CT, the mean SUV{sub max} of malignant octants was significantly higher than the mean SUV{sub max} of benign octants (3.69 {+-} 1.29 vs. 3.06 {+-} 0.97, p < 0.0001) which was also true for mean SUV{sub mean} values (2.39 {+-} 0.77 vs. 1.94 {+-} 0.61, p < 0.0001). A positive correlation was observed between SUV{sub mean} and absolute tumor volume (Spearman r = 0.3003, p = 0.0362). No correlation was found between SUVs and prostate-specific antigen, T-stage or Gleason score. The highest accuracy (61.1%) was obtained with a SUV{sub max} cutoff of 2.70, resulting in a sensitivity of 77.4% and a specificity of 44.9%. When both modalities were combined (PET-CT or MRI positive), sensitivity levels increased as a function of SUV{sub max} but at the cost of specificity. When only considering suspect octants on {sup 11}C-choline PET-CT (SUV{sub max} {>=} 2.70) and T2w MRI, 84.7% of these segments were in agreement with the gold standard, compared with 80.5% for T2w MRI alone. Conclusions: The additional value of {sup

  18. CT diagnosis of empty sella

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    Machida, T.; Maehara, T. (Tokyo Univ. (Japan). Faculty of Medicine)

    1981-02-01

    The CT diagnosis of an empty sella was discussed, using coronal and reconstructed sagittal planes after the intrathecal injection of metrizamide. Results: 1) The diagnosis of an empty sella should be made by noninvasive radiological examination, if possible. Computed Tomography is the most appropriate procedure for the diagnosis of an empty sella. 2) Coronal and reconstructed sagittal CT are of more diagnostic use than axial CT in the diagnosis of an empty sella. 3) At present, we should use metrizamide to eliminate a low-density mass in sella turcica. 4) In the near future, we will be able to make a diagnosis of an empty sella by plain CT alone, using a thinner slice and a higher resolution for low attenuation values. 5) We cannot detect pituitary microadenoma itself by CT in most cases of pituitary adenomas with a coexisting partially empty sella. We should, therefore, use other, detailed neuroradiological investigations if the endocrinologic evaluation of a patient supports the possibility of pituitary adenoma.

  19. Functional CT of the kidney

    Energy Technology Data Exchange (ETDEWEB)

    Tsushima, Yoshito. E-mail: yoshito@xa2.so-net.ne.jp

    1999-06-01

    The iodinated contrast agents used for computed tomography (CT) are filtered at the glomerulus and not reabsorbed by the tubules and have pharmacokinetics comparable to inulin. They can thus measure physiological indices such as contrast clearance per unit volume, which is closely related to glomerular filtration rate per unit renal volume of kidney, after due allowance for the difference between blood and plasma clearance. In this review, we show how dynamic CT can be used to measure both regional and global blood clearance of contrast material. A single slice of kidney is scanned sequentially after bolus intravenous (i.v.) injection of contrast material. Next, time-attenuation curves are constructed and contrast clearance per unit volume is calculated using a Patlak graphical analysis. CT determination of renal volume is made and global contrast clearance can be then also calculated. In normal kidneys, clearance/volume averaged 0.49{+-}0.11 ml min{sup -1} ml{sup -1} (mean {+-}S.D.), and these values agreed with literature data obtained using other techniques. A negative correlation between patient's age and clearance/volume was seen. A strong correlation was observed between creatinine whole blood clearance and the global contrast clearance (the product of renal volume determined by CT and contrast clearance/volume). Dynamic CT can provide quantitative renal physiological information on a regional basis non-invasively.

  20. 双源CT灌注扫描对胰腺癌诊断的应用价值%The value of CT perfusion in diagnosis of pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    柴瑞梅; 任克; 张智伟; 王强; 赵宇; 赵丽; 徐克

    2013-01-01

    Objective To evaluate the perfusion features of pancreatic cancer and the clinical value of perfusion CT in diagnosis.Methods Perfusion CT was performed in 104 patients who were suspected as pancreatic cancer with a 64-slice CT using a dynamic sequence after contrast-enhanced CT.Compare the perfusion parameters between cancer tissue and peripheral healthy tissue.Analyze the diagnostic accuracies between the perfusion CT combined with routine CT and single routine CT method.Results Seventy three patients were confirmed as pancreatic cancer by histopathologic examination or follow-up.The perfusion parameters of lesion were lower than that of peripheral healthy tissue,and the values of Flow,BV and pBV had significant differences (P < 0.05).The perfusion CT combining with contrast-enhanced CT had a higher susceptibility (98.6%),specificity (90.3%),positive predictive value(96.0%),negative predictive value(96.5%)and accuracy(96.2%)than contrast-enhanced CT.Conclusions CT perfusion could reflect the feature of low blood supply of pancreatic cancer.It could improve the diagnostic capability of pancreatic cancer.%目的 探讨CT灌注对胰腺癌诊断的应用价值.方法 采用Siemens双源CT扫描仪,对104例临床怀疑为胰腺癌或经超声检查发现胰腺占位性病变者进行CT灌注检查.比较胰腺癌组织与周围正常组织间各灌注参数值差异,比较常规增强CT方法及其与CT灌注相结合对于胰腺癌的检出率.结果 经手术病理或临床检查证实73例为胰腺癌.胰腺癌组织的灌注参数值血流量(Flow),血容量(blood volume,BV),通透性(permeability,per)及Patlak血流量(patlak blood volume,pBV)分别为(68.34±30.06) ml·(100 ml)-1·min-1,(112.75 ±39.57)∶ 1000,(64.14±27.28)0.5 ml· (100 ml)-1·min-1,(56.87 ±32.62)∶1000,均较周围正常胰腺组织低(P<0.05).CT灌注方法结合常规增强CT检查具有较高的敏感度(98.6%)、特异度(90.3%)、阳性预测值(96.0

  1. Prognostic Value of Gastric Bare Area & Left Adrenal Gland Involvement in Acute Pancreatitis on Abdominal CT SCAN

    Directory of Open Access Journals (Sweden)

    Saeed Naghibi

    2009-01-01

    Full Text Available "nIntroduction: The CT severity index (CTSI proposed by Baithazar is a well-defined scoring system and has proved to be an excellent prognostic tool in predicting complications and mortality in patients with acute pancreatitis .But new investigations demonstrate that the other findings on abdominal CT scan in acute pancreatitis impression on prognostic outcome (involvement of abdominal viscera. Therefore the newer scoring system has been proposed. In our study the involvement of gastric bare area & left adrenal gland in CT scan is usually associated with a more severe clinical course. "nMaterials and Methods: This study was a retrospective & prospective evaluation in 22-Bahman Hospital of AZAD University of Mashhad from 2006 to 2008 .78 patients with acute pancreatitis (based on a typical clinical presentation & an elevated serum amylase level and "or pathologic findings had undergone the abdominal spiral CT scan with oral & IV contrast (if necesary. 28 cases were excluded from the study population for the following reasons: CT was not performed (n=10 ; CT images were not available (n=13; inadequate data analysis (n=2; and acute pancreatitis was not the first episode (n=3. "nFollow-up CT was performed within 1 week after the initial CT. Leaving 50 patients in our study there were 32 men and 18 women in the age range of 21-82 years (50.5+_ 18.2 years. All the patients underwent unenhanced CT followed by dual-phase contrast-enhanced CT. The arterial and portal venous phase data acquisition started at 25-30s and 60-65s after injection of contrast. Then two experienced abdominal radiologists recorded the findings of CT scan including the size,contour and density of the pancreas and manifestations of peripancreatic inflammation as well as the GBAI and LAGI involvement (haziness and streaky density with fluid collection in the gastric bare area and deformity with ill-defined margin and hypodensity of the left adrenal gland on unenhanced or contrast

  2. Quantitative CT characterization of pediatric lung development using routine clinical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Jill M.; Brody, Alan S.; Fleck, Robert J. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Walkup, Laura L. [Cincinnati Children' s Hospital Medical Center, Center for Pulmonary Imaging Research, Pulmonary Medicine and Radiology, Cincinnati, OH (United States); Woods, Jason C. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Center for Pulmonary Imaging Research, Pulmonary Medicine and Radiology, Cincinnati, OH (United States)

    2016-12-15

    The use of quantitative CT analysis in children is limited by lack of normal values of lung parenchymal attenuation. These characteristics are important because normal lung development yields significant parenchymal attenuation changes as children age. To perform quantitative characterization of normal pediatric lung parenchymal X-ray CT attenuation under routine clinical conditions in order to establish a baseline comparison to that seen in pathological lung conditions. We conducted a retrospective query of normal CT chest examinations in children ages 0-7 years from 2004 to 2014 using standard clinical protocol. During these examinations semi-automated lung parenchymal segmentation was performed to measure lung volume and mean lung attenuation. We analyzed 42 CT examinations in 39 children, ages 3 days to 83 months (mean ± standard deviation [SD] = 42 ± 27 months). Lung volume ranged 0.10-1.72 liters (L). Mean lung attenuation was much higher in children younger than 12 months, with values as high as -380 Hounsfield units (HU) in neonates (lung volume 0.10 L). Lung volume decreased to approximately -650 HU by age 2 years (lung volume 0.47 L), with subsequently slower exponential decrease toward a relatively constant value of -860 HU as age and lung volume increased. Normal lung parenchymal X-ray CT attenuation decreases with increasing lung volume and age; lung attenuation decreases rapidly in the first 2 years of age and more slowly thereafter. This change in normal lung attenuation should be taken into account as quantitative CT methods are translated to pediatric pulmonary imaging. (orig.)

  3. Prognostic Value of Negative Coronary CT Angiography in Severely Obese Patients Prior to Bariatric Surgery: a Follow-Up After 6 Years.

    Science.gov (United States)

    Messerli, Michael; Maywald, Céline; Wälti, Stephan; Warschkow, René; Wildermuth, Simon; Alkadhi, Hatem; Leschka, Sebastian; Schiesser, Marc

    2017-08-01

    This study aims to determine the long-term prognostic value of coronary CT angiography (CCTA) prior to bariatric surgery in severely obese patients with a body mass index (BMI) ≥35 kg/m(2). Seventy consecutive patients undergoing cardiac CT for coronary assessment prior to bariatric surgery were prospectively included. Images were analysed for the presence of coronary calcification and for non-obstructive (50% stenosis) coronary artery disease (CAD). A median clinical follow-up of 6.1 years in 54 patients was obtained for major adverse cardiovascular events (MACEs), defined as death, non-fatal myocardial infarction or coronary revascularisation. Weight loss and BMI decrease following bariatric surgery were recorded. The median BMI prior to surgery was 46.9 kg/m(2). The median percentage of excess BMI loss after surgery was 75%. CT showed coronary calcification in 26 (48%) patients, whereas 28 (52%) patients had no calcification. CCTA revealed normal coronaries in 47 (87%) and non-obstructive CAD in 7 (13%) patients. No obstructive CAD was found. All patients successfully underwent bariatric surgery, and no MACE occurred neither perioperatively nor in the follow-up period. The negative predictive value of CCTA was 100% (95% confidence interval of 90.1-100.0%). In severely obese patients, the absence of obstructive CAD in cardiac CT prior to bariatric surgery with subsequently marked weight reduction has strong long-term prognostic implications for ruling out major adverse cardiac events in the postoperative period.

  4. Maximum standardized uptake value on PET/CT in preoperative assessment of lymph node metastasis from thoracic esophageal squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    Amos JM Ela Bella; Ya-Rui Zhang; Wei Fan; Kong-Jia Luo; Tie-Hua Rong; Peng Lin; Hong Yang; Jian-Hua Fu

    2014-01-01

    The presence of lymph node metastasis is an important prognostic factor for patients with esophageal cancer. Accurate assessment of lymph nodes in thoracic esophageal carcinoma is essential for selecting appropriate treatment and forecasting disease progression. Positron emission tomography combined with computed tomography (PET/CT) is becoming an important tool in the workup of esophageal carcinoma. Here, we evaluated the effectiveness of the maximum standardized uptake value (SUVmax) in assessing lymph node metastasis in esophageal squamous cell carcinoma (ESCC) prior to surgery. Fifty-nine surgical patients with pathologically confirmed thoracic ESCC were retrospectively studied. These patients underwent radical esophagectomy with pathologic evaluation of lymph nodes. They al had 18F-FDG PET/CT scans in their preoperative staging procedures. None had a prior history of cancer. The pathologic status and PET/CT SUVmax of lymph nodes were col ected to calculate the receiver operating characteristic (ROC) curve and to determine the best cutoff value of the PET/CT SUVmax to distinguish benign from malignant lymph nodes. Lymph node data from 27 others were used for the validation. A total of 323 lymph nodes including 39 metastatic lymph nodes were evaluated in the training cohort, and 117 lymph nodes including 32 metastatic lymph nodes were evaluated in the validation cohort. The cutoff point of the SUVmax for lymph nodes was 4.1, as calculated by ROC curve (sensitivity, 80%; specificity, 92%;accuracy, 90%). When this cutoff value was applied to the validation cohort, a sensitivity, a specificity, and an accuracy of 81%, 88%, and 86%, respectively, were obtained. These results suggest that the SUVmax of lymph nodes predicts malignancy. Indeed, when an SUVmax of 4.1 was used instead of 2.5, FDG-PET/CT was more accurate in assessing nodal metastasis.

  5. CT对腔隙性脑梗死患者近期预后风险的评估%The Risk of Short-term Prognosis Evaluation Values of CT for the Patients with Lacunar Infarction

    Institute of Scientific and Technical Information of China (English)

    刘东顺; 张敏丽; 李翠乔; 司翠权

    2015-01-01

    目的:探讨CT对腔隙性脑梗死患者近期预后风险的评估价值.方法:选取2011年6月-2014年8月笔者所在医院收治的腔隙性脑梗死患者80例,都进行CT检测,同时选择PRR比率和NIHSS评分进行近期预后风险评估.结果:腔隙性脑梗死患者的CT主要表现为形态卵圆形,病灶内部密度大,伴随有豆状核钙化;同时梗死区的CBF和CBV值都明显少于缺血半暗带区,而MTT值明显高于缺血半暗带区(P<0.05).80例患者的PRR比率为(67.33±2.19)%,NIHSS评分为(34.09±12.44)分,Pearson分析显示CBF和CBV值与PRR比率和NIHSS评分存在明显负相关(P<0.05),而MTT值与PRR比率和NIHSS评分存在明显正相关(P<0.05).结论:腔隙性脑梗死在CT灌注参数上有很好的特异性表现,同时对于近期预后风险有很好的指导判定作用,值得推广应用.%Objective:To investigate the risk of short-term prognosis evaluation values of CT for the patients with lacunar infarction. Method:80 lacunar infarction patients which were admitted to our hospital from June 2011 to August 2014 were selected,all the patients were performed CT detection,and the PRR rates and NIHSS scores for the short-term prognosis risk assessment were choosed.Result:CT attenuation mainly for patients with lacunar infarction were showed oval shape,large lesions internal density,accompanied lenticular nucleus calcification;and the CBF and CBV values in the infarct zone were significantly less than the ischemic penumbra,and MTT were significantly higher than the ischemic penumbra(P<0.05).80 patients of the PRR ratios were (67.33±2.19)%,NIHSS scores were 34.09±12.44 points,Pearson analysis showed that CBF and CBV values were negative correlated to the PRR ratio and NIHSS scores(P<0.05),while the values of MTT values were significant positive correlated to the PRR ratio and NIHSS scores(P<0.05).Conclusion:Lacunar infarction on CT perfusion parameters has good specific performance,while has risk of short

  6. Clinical value of FDG PET or PET/CT in urinary bladder cancer: A systemic review and meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yu-Yu, E-mail: yuoyuolu@vghtc.gov.tw [Department of Nuclear Medicine, Taichung Veterans General Hospital, Taichung, Taiwan (China); Chen, Jin-Hua, E-mail: chenjh99@mail.cmu.edu.tw [Biostatistics Center and Graduate Institute of Biostatistics, China Medical University, Taichung, Taiwan (China); Liang, Ji-An, E-mail: hope.jal@msa.hinet.net [Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan (China); School of Medicine, China Medical University, Taichung, Taiwan (China); Wang, Hsin-Yi, E-mail: hywang@vghtc.gov.tw [Department of Nuclear Medicine, Taichung Veterans General Hospital, Taichung, Taiwan (China); Lin, Cheng-Chieh, E-mail: cclin@mail.cmuh.org.tw [School of Medicine, China Medical University, Taichung, Taiwan (China); Department of Community Medicine and Health Examination Center, China Medical University Hospital, Taichung, Taiwan (China); Lin, Wan-Yu, E-mail: wylin@vghtc.gov.tw [Department of Nuclear Medicine, Taichung Veterans General Hospital, Taichung, Taiwan (China); School of Medicine, China Medical University, Taichung, Taiwan (China); Kao, Chia-Hung, E-mail: d10040@mail.cmuh.org.tw [School of Medicine, China Medical University, Taichung, Taiwan (China); Department of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan (China)

    2012-09-15

    Aim: The purpose of the current study was to conduct a systemic review and meta-analysis of the published literature to evaluate the diagnostic accuracy of FDG PET or PET/CT in urinary bladder cancer. Materials and methods: The authors conducted a systematic MEDLINE search of articles published between January 2000 and December 2010. Two reviewers independently assessed the methodological quality of each study. We conducted a meta-analysis of pooled sensitivity and specificity in detecting primary and metastatic lesions of bladder cancer. Results: Six studies met the inclusion criteria. The pooled sensitivity and specificity of PET/CT for primary lesion detection of bladder cancer were 0.90 (95% CI: 0.70–0.99) and 1.00 (95% CI: 0.74–1.00), respectively. The pooled sensitivity and specificity of FDG PET or PET/CT for staging or restaging (metastatic lesions) of bladder cancer were 0.82 (95% CI: 0.72–0.89) and 0.89 (95% CI: 0.81–0.95), respectively. Conclusion: The diagnostic accuracy of FDG PET or PET/CT is good in metastatic lesions of urinary bladder cancer. Due to the small number of patients and limited number of studies analyzed, the diagnostic capability of FDG PET or PET/CT in detection of primary bladder wall lesions could not be assessed.

  7. FDG-PET/CT in advanced ovarian cancer staging: Value and pitfalls in detecting lesions in different abdominal and pelvic quadrants compared with laparoscopy

    Energy Technology Data Exchange (ETDEWEB)

    De Iaco, Pierandrea [Department of Gynaecology, Azienda Ospedaliero-Universitaria di Bologna, Policlinico S.Orsola-Malpighi, Bologna (Italy); Musto, Alessandra [Department of Nuclear Medicine, Azienda Ospedaliero-Universitaria di Bologna, Policlinico S.Orsola-Malpighi, Bologna (Italy); Orazi, Luca [Department of Gynaecology, Azienda Ospedaliero-Universitaria di Bologna, Policlinico S.Orsola-Malpighi, Bologna (Italy); Zamagni, Claudio; Rosati, Marta [Department of Medical Oncology, Azienda Ospedaliero-Universitaria di Bologna, Policlinico S.Orsola-Malpighi, Bologna (Italy); Allegri, Vincenzo [Department of Nuclear Medicine, Azienda Ospedaliero-Universitaria di Bologna, Policlinico S.Orsola-Malpighi, Bologna (Italy); Cacciari, Nicoletta [Department of Medical Oncology, Azienda Ospedaliero-Universitaria di Bologna, Policlinico S.Orsola-Malpighi, Bologna (Italy); Al-Nahhas, Adil [Department of Nuclear Medicine, Hammersmith Hospital, London (United Kingdom); Rubello, Domenico, E-mail: domenico.rubello@libero.it [Department of Nuclear Medicine, PET/CT Centre, Radiology, Medical Physics, ' Santa Maria della Misericordia' Hospital, Viale Tre Martiri 140, 45100 Rovigo (Italy); Venturoli, Stefano [Department of Gynaecology, Azienda Ospedaliero-Universitaria di Bologna, Policlinico S.Orsola-Malpighi, Bologna (Italy); Fanti, Stefano [Department of Nuclear Medicine, Azienda Ospedaliero-Universitaria di Bologna, Policlinico S.Orsola-Malpighi, Bologna (Italy)

    2011-11-15

    Introduction and aim: Ovarian carcinoma (OC) is a common cancer in the Western Countries, and an important cause of death in patients suffering with gynaecologic malignancies. The majority of patients present with advanced disease at the time of diagnosis. Treatment with debulking surgery followed by chemotherapy is the standard approach while chemotherapy is contemplated when surgery is not possible. A correct pre-operative staging is important to ensure a most appropriate management. Laparoscopy (LPS) is the standard diagnostic tool for the assessment of intraperitoneal infiltration but is invasive and requires general anaesthesia. FDG-PET/CT is increasingly used for staging different types of cancer, and the aim of this study is to assess the value of FDG-PET/CT in staging advanced OC and its sensitivity to detect lesions in different quadrants of the abdominal-pelvic area compared to laparoscopy. Materials and methods: From September 2004 till April 2008, 40 patients with high suspicion of OC were referred to our hospital for diagnostic LPS to explore the possibility of optimal debulking surgery. Those who were not suitable for surgery were referred for chemotherapy. Before chemotherapy, the patients underwent an FDG-PET/CT scan. The findings in 9 quadrants of abdominal-pelvic area (total 360 quadrants) for PET/CT and LPS were recorded and compared. Results: In 14/360 areas (3.8%), surgical evaluation was not possible because of presence of adhesions, thus the number of areas explored by laparoscopy was 346. Tumour was found in 308 quadrants (38 quadrants free of disease). PET/CT was positive in all 40 patients with true negative results in 26/346 quadrants (7.5%), and true positives results in 243/346 quadrants (70.2%). False positive and negative PET/CT results were found in 12/346 and 65/346 quadrants, respectively. False positive PET/CT findings were evenly present in all quadrants. False negative PET/CT findings were present in 31/109 (28.4%) upper

  8. The diagnostic value of PET/CT imaging with the {sup 68}Ga-labelled PSMA ligand HBED-CC in the diagnosis of recurrent prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Afshar-Oromieh, Ali; Giesel, Frederik L.; Kratochwil, Clemens; Haberkorn, Uwe [University Hospital of Heidelberg, Department of Nuclear Medicine, Heidelberg (Germany); Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Centre, Heidelberg (Germany); Avtzi, Eleni [University Hospital of Heidelberg, Department of Nuclear Medicine, Heidelberg (Germany); Holland-Letz, Tim [German Cancer Research Center, Department of Biostatistics, Heidelberg (Germany); Linhart, Heinz G. [German Cancer Research Centre, Heidelberg, National Centre for Tumor Diseases (NCT), Heidelberg (Germany); Eder, Matthias; Eisenhut, Michael; Kopka, Klaus [German Cancer Research Center, Division of Radiopharmaceutical Chemistry, Heidelberg (Germany); Boxler, Silvan; Hadaschik, Boris A. [University Hospital of Heidelberg, Department of Urology, Heidelberg (Germany); Weichert, Wilko [University Hospital of Heidelberg, Department of Pathology, Heidelberg (Germany); Debus, Juergen [University Hospital Heidelberg, Department of Radiation Oncology and Therapy, Heidelberg (Germany)

    2014-11-20

    Since the introduction of positron emission tomography (PET) imaging with {sup 68}Ga-PSMA-HBED-CC (={sup 68}Ga-DKFZ-PSMA-11), this method has been regarded as a significant step forward in the diagnosis of recurrent prostate cancer (PCa). However, published data exist for small patient cohorts only. The aim of this evaluation was to analyse the diagnostic value of {sup 68}Ga-PSMA-ligand PET/CT in a large cohort and the influence of several possibly interacting variables. We performed a retrospective analysis in 319 patients who underwent {sup 68}Ga-PSMA-ligand PET/CT from 2011 to 2014. Potential influences of several factors such as prostate-specific antigen (PSA) level and doubling time (DT), Gleason score (GSC), androgen deprivation therapy (ADT), age and amount of injected tracer were evaluated. Histological verification was performed in 42 patients after the {sup 68}Ga-PSMA-ligand PET/CT. Tracer uptake was measured in 901 representative tumour lesions. In 82.8 % of the patients at least one lesion indicative of PCa was detected. Tumor-detection was positively associated with PSA level and ADT. GSC and PSA-DT were not associated with tumor-detection. The average maximum standardized uptake value (SUV{sub max}) of tumour lesions was 13.3 ± 14.6 (0.7-122.5). Amongst lesions investigated by histology, 30 were false-negative in 4 different patients, and all other lesions (n = 416) were true-positive or true-negative. A lesion-based analysis of sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) revealed values of 76.6 %, 100 %, 91.4 % and 100 %. A patient-based analysis revealed a sensitivity of 88.1 %. Of 116 patients available for follow-up, 50 received local therapy after {sup 68}Ga-PSMA-ligand PET/CT. {sup 68}Ga-PSMA-ligand PET/CT can detect recurrent PCa in a high number of patients. In addition, the radiotracer is highly specific for PCa. Tumour detection is positively associated with PSA and ADT. {sup 68}Ga

  9. Value of automatic bone subtraction in cranial CT angiography: comparison of bone-subtracted vs. standard CT angiography in 100 patients

    Energy Technology Data Exchange (ETDEWEB)

    Morhard, Dominik; Fink, Christian; Becker, Christoph; Reiser, Maximilian F.; Nikolaou, Konstantin [Ludwig-Maximilians-University of Munich, Institute of Clinical Radiology, Munich (Germany)

    2008-05-15

    Non-contrast-enhanced cranial computed tomography (NECT) and CT angiography (CTA) are the most frequently used modalities in the triage of patients with acute ischemic and hemorrhagic stroke. CTA bone removal can improve the delineation of vasculature closely adjacent to bony structures, which is sometimes limited in standard CTA. The aim of this study was the evaluation of the clinical benefit of bone subtraction (BS) regarding delineation of cerebral vasculature, reading time and depiction of vascular pathologies compared to standard CTA without BS. A total of 100 patients who underwent NECT and supraaortic CTA on a 64-slice CT system were retrospectively included in the study. Bone removal was performed by subtraction of the NECT data from the CTA data using a dedicated workstation. Standard and BS CTA of each patient was reviewed for delineation of cerebral vasculature (grading scale from 1 = 'excellent delineation' to 10 = 'hardly any delineation'), reading time and depiction of vascular pathologies (standardized catalog) by two blinded readers. For BS data sets, the quality of BS was rated by a combination of the criteria complete bone removal, depiction of vascular structures and sufficient quality for diagnostic evaluation. The use of BS significantly reduced reading time from 4.60 min to 3.49 min (p < 0.001). Performing BS, the quality of vascular delineation of the cerebral arteries, cerebral veins and cavernous segment of the ICA increased significantly as compared to standard CTA (1.70 vs. 2.70; 2.60 vs. 4.12; 2.35 vs. 4.40, all p < 0.001). Consensus reading showed 41 pathologies in 35 patients. Diagnosis was missed or wrong overall in 15 cases, with 3 missed aneurysms (CTA: 2 vs. BS: 1), 8 wrong stenotic findings (CTA: 3 vs. BS: 5) and 4 missed partial thromboses (CTA: 2 vs. BS: 2). Performing BS in supraaortic CTA for the evaluation of cerebral vasculature reduces reading time and improves delineation of vessels. Diagnostic

  10. Value of the post-operative CT in predicting delayed flap failures following head and neck cancer surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bitna; Yoon, Dae Young; Seo, Young Lan; Park, Min Woo; Kwon, Kee Hwan; Rho, Young Soo; Chung, Chul Hoon [Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul (Korea, Republic of)

    2017-06-15

    To identify post-operative computed tomography (CT) findings associated with delayed flap failures following head and neck cancer surgery. We retrospectively reviewed 60 patients who underwent flap reconstruction after head and neck cancer surgery and post-operative (3–14 days) contrast-enhanced CT scans for suspected complications. Patients were divided into two groups: delayed flap failure patients (patients required flap revision) (n = 18) and flap success patients (n = 42). Clinical data (age, sex, T-stage, type of flap, and time interval between reconstruction surgery and CT) and post-operative CT findings of flap status (maximum dimension of the flap, intra- or peri-flap fluid collection and intra- or peri-flap air collection, fat infiltration within the flap, fistula to adjacent aerodigestive tract or skin, and enhanced vascular pedicle) were assessed and compared between the two groups. CT findings showed that the following flap anomalies were observed more frequently in the delayed flap failure group than in the flap success group: intra- or peri-flap fluid collection > 4 cm (61.1% vs. 23.8%, p < 0.05), intra- or peri-flap air collection > 2 cm (61.1% vs. 2.4%, p < 0.001), and fistula to adjacent aerodigestive tract or skin (44.4% vs. 0%, p < 0.001). The maximum dimension of the flap, fat infiltration within the flap, and enhanced vascular pedicle were not associated with delayed flap failures. A large amount of fluid or air collection and fistula are the CT findings that were associated with delayed flap failures in patients with suspected post-operative complications after head and neck cancer surgery.

  11. WE-AB-204-06: Pseudo-CT Generation Using Undersampled, Single-Acquisition UTE-MDixon and Direct-Mapping Artificial Neural Networks for MR-Based Attenuation Correction and Radiation Therapy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Su, K; Kuo, J [Case Center for Imaging Research, Case Western Reserve University, Cleveland, Ohio (United States); Department of Radiology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio (United States); Hu, L; Traughber, M [Philips Healthcare, Cleveland, Ohio (United States); Pereira, G; Traughber, B [Department of Radiation Oncology, University Hospitals Seidman Cancer Center, Case Western Reserve University, Cleveland, Ohio (United States); Herrmann, K [Department of Radiology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio (United States); Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, Ohio (United States); Muzic, R [Case Center for Imaging Research, Case Western Reserve University, Cleveland, Ohio (United States); Department of Radiology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio (United States); Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH (United States)

    2015-06-15

    Purpose: Emerging technologies such as dedicated PET/MRI and MR-therapy systems require robust and clinically practical methods for determining photon attenuation. Herein, we propose using novel MR acquisition methods and processing for the generation of pseudo-CTs. Methods: A single acquisition, 190-second UTE-mDixon sequence with 25% (angular) sampling density and 3D radial readout was performed on nine volunteers. Three water-filled tubes were placed in the FOV for trajectory-delay correction. The MR data were reconstructed to generate three primitive images acquired at TEs of 0.1, 1.5 and 2.8 ms. In addition, three derived MR images were generated, i.e. two-point Dixon water/fat separation and R2* (1/T2*) map. Furthermore, two spatial features, i.e. local binary pattern (S-1) and relative spatial coordinates (S-2), were incorporated. A direct-mapping operator was generated using Artificial Neural Networks (ANNs) for transforming the MR features to a pseudo-CT. CT images served as the training data and, using a leave-one-out method, for performance evaluation using mean prediction deviation (MPD), mean absolute prediction deviation (MAPD), and correlation coefficient (R). Results: The errors between measured CT and pseudo-CT declined dramatically when the spatial features, i.e. S-1 and S-2, were included. The MPD, MAPD, and R were, respectively, 5±57 HU, 141±41 HU, and 0.815±0.066 for results generated by the ANN trained without the spatial features and were 32±26 HU, 115±18 HU, and 0.869±0.035 with the spatial features. The estimation errors of the pseudo-CT were smaller when both the S-1 and S-2 were used together than when either the S-1 or the S-2 was used. Pseudo-CT generation (256×256×256 voxels) by ANN took < 0.5 s using a computer having an Intel i7 3.4GHz CPU and 16 GB RAM. Conclusion: The proposed direct-mapping ANN approach is a technically accurate, clinically practical method for pseudo-CT generation and can potentially help improve the

  12. 双源 CT 双能量技术在泌尿系结石诊断中的应用价值%Application value of dual energy technique of dual source CT in the diagnosis of urinary calculi

    Institute of Scientific and Technical Information of China (English)

    高江晖; 马洪宇; 郭文伟; 于庆康

    2016-01-01

    目的:探讨双源 CT 双能量技术在尿路结石组成分析中的预测价值。方法对30例泌尿系统结石患者行双源 CT 双能量扫描,对结石组成成份进行分析,将结果与红外光谱法分析的结石组成相比,计算双源 CT 分析尿酸盐结石、非尿酸盐结石的特异度与灵敏度,判断预测结石的准确性。结果30例泌尿系结石中尿酸盐类结石10例,非尿酸盐类结石20例,尿酸盐结石、非尿酸盐结石在140 kV 能量下 CT 值分别为(312.5±55.5)HU、(650.6±255.5)HU,在100 kV 能量下 CT 值分别为(328.5±50.5)HU、(960.8±180.5)HU,尿酸盐结石、非尿酸盐结石在两种能量下的差值分别为(16.5±5.1)HU、(310.2±26.7)HU,比值分别为(1.05±0.01)HU、(1.47±0.02) HU,尿酸盐结石差值、比值明显低于非尿酸盐结石(P <0.05),双源 CT 可切确辨别尿酸盐类结石与非尿酸盐类结石,其灵敏度、特异度分别为90%、95%。结论双源 CT 双能量成像技术能在尿路结石治疗前对其组成进行分析,对认识结石的成因及预防结石形成有很大帮助。%Objective To investigate the clinical value of dual source dual energy CT( DS-DECT)in predict chemical component of urinary calculi. Methods Selected 30 cases with urinary cal-culi underwent dual source Flash CT,analysed the component of the calculi,compared the results and in-frared spectroscopy analysis of calculi composition,calculated the specificity and sensitivity of urate cal-culi,non urate calculus by dual source CT analysis,and judged the forecasting accuracy of the calculi. Results Among the 30 urinary calculi patients,10 cases had uric acid calculi and 20 cases had non-u-ric acid calculi. Uric acid calculi and non-uric acid calculi under 140 kV energy:CT values were (312. 5 ± 55. 5)HU,(650. 6 ± 255. 5)HU;under 100 kV energy:CT values were(328. 5 ± 50. 5) HU,(960. 8 ± 180. 5)HU;the difference of acid

  13. Diagnostic value of [{sup 18}F]-FDG PET/CT in children with fever of unknown origin or unexplained signs of inflammation

    Energy Technology Data Exchange (ETDEWEB)

    Jasper, Niklas; Daebritz, Jan; Frosch, Michael; Foell, Dirk [University of Muenster, Department of Pediatrics, Muenster (Germany); Loeffler, Markus [University of Muenster, Department of Nuclear Medicine, Muenster (Germany); Clemenshospital, Department of Radiology, Muenster (Germany); Weckesser, Matthias [University of Muenster, Department of Nuclear Medicine, Muenster (Germany)

    2010-01-15

    Fever of unknown origin (FUO) and unexplained signs of inflammation are challenging medical problems especially in children and predominantly caused by infections, malignancies or noninfectious inflammatory diseases. The aim of this study was to assess the diagnostic value of {sup 18}F-FDG PET and PET/CT in the diagnostic work-up in paediatric patients. In this retrospective study, 47 FDG PET and 30 PET/CT scans from 69 children (median age 8.1 years, range 0.2-18.1 years, 36 male, 33 female) were analysed. The diagnostic value of PET investigations in paediatric patients presenting with FUO (44 scans) or unexplained signs of inflammation without fever (33 scans) was analysed. A diagnosis in paediatric patients with FUO or unexplained signs of inflammation could be established in 32 patients (54%). Of all scans, 63 (82%) were abnormal, and of the total number of 77 PET and PET/CT scans 35 (45%) were clinically helpful. In patients with a final diagnosis, scans were found to have contributed to the diagnosis in 73%. Laboratory, demographic or clinical parameters of the children did not predict the usefulness of FDG PET scans. This is the first larger study demonstrating that FDG PET and PET/CT may be valuable diagnostic tools for the evaluation of children with FUO and unexplained signs of inflammation. Depicting inflammation in the whole body, while not being traumatic, it is attractive for use especially in children. The combination of PET with CT seems to be superior, since the site of inflammation can be localized more accurately. (orig.)

  14. Clinical value of CT in diagnosis of acute appendicitis%急性阑尾炎的CT诊断及临床应用价值

    Institute of Scientific and Technical Information of China (English)

    唐俊军; 黄宗良; 王国良

    2015-01-01

    目的 提高对CT在急性阑尾炎诊断中重要性的认识.方法 回顾性分析经手术病理证实的87例急性阑尾炎的CT表现.结果 87例急性阑尾炎中,单纯性阑尾炎45例,阳性40例,阴性5例;化脓性阑尾炎28例,坏疽穿孔性阑尾炎7例,阑尾周围脓肿7例均出现相应的CT表现.CT表现为阑尾肿大,管径增粗,阑尾壁不同程度水肿,同时可合并周围炎性渗出或脓肿形成.结论 CT对急性阑尾炎的诊断及临床应用有很大的价值.%Objective To enhance the application value of CT in diagnosis of acute appendicitis. Methods CT findings of 87 cases with acute appendicitis confirmed by surgery and pathology were retrospectively analyzed. Results There were 87 cases of acute appendicitis,45 cases of simple appendicitis,28 cases of suppurative appendicitis,7 cases of gangrenous appendicitis,7 cases of appendiceal abscess. CT findings of 5 cases of simple appendicitis were negative. CT showed swelling of the appendix,edema of the appendix wall and the abscess of the appendix. Conclusion CT imaging is of great value in the diagnosis of acute appendicitis.

  15. Diagnostic value of combining {sup 11}C-choline and {sup 18}F-FDG PET/CT in hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Castilla-Lievre, Maria-Angela [University Department Hepatinov, Assistance-Publique Hopitaux de Paris, Department of Nuclear Medicine, Hopital Antoine Beclere, Clamart (France); IMIV - UMR 1023 Inserm/CEA/Universite Paris Sud - ERL 9218 CNRS, Orsay (France); Franco, Dominique [Universite Paris-Sud, Department of Surgery, Hopital Antoine Beclere, University Department Hepatinov, Assistance-Publique Hopitaux de Paris, Clamart (France); Gervais, Philippe; Kuhnast, Bertrand; Desarnaud, Serge; Helal, Badia-Ourkia [IMIV - UMR 1023 Inserm/CEA/Universite Paris Sud - ERL 9218 CNRS, Orsay (France); CEA, DSV, I2BM, Service Hospitalier Frederic Joliot, Orsay (France); Agostini, Helene [University Department Hepatinov, Assistance-Publique Hopitaux de Paris, Clinical Research Unit of Hopitaux universitaires Paris-Sud, Hopital Kremlin Bicetre (France); Marthey, Lysiane [Universite Paris-Sud, Department of Gastroenterology, Hopital Antoine Beclere, University Department Hepatinov, Assistance-Publique Hopitaux de Paris, Clamart (France)

    2016-05-15

    In this prospective study, our goal was to emphasize the diagnostic value of combining {sup 11}C-choline and {sup 18}F-FDG PET/CT for hepatocellular carcinoma (HCC) in patients with chronic liver disease. Thirty-three consecutive patients were enrolled. All patients were suspected to have HCC based on CT and/or MRI imaging. A final diagnosis was obtained by histopathological examination or by imaging alone according to American Association for the Study of Liver Disease criteria. All patients underwent PET/CT with both tracers within a median of 5 days. All lesions showing higher tracer uptake than normal liver were considered positive for HCC. We examined how tracer uptake was related to biological (serum α-fetoprotein levels) and pathological (differentiation status, peritumoral capsule and vascular invasion) prognostic markers of HCC, as well as clinical observations at 6 months (recurrence and death). Twenty-eight HCC, four cholangiocarcinomas and one adenoma were diagnosed. In the HCC patients, the sensitivity of {sup 11}C-choline, {sup 18}F-FDG and combined {sup 11}C-choline and {sup 18}F-FDG PET/CT for the detection of HCC was 75 %, 36 % and 93 %, respectively. Serum α-fetoprotein levels >200 ng/ml were more frequent among patients with {sup 18}F-FDG-positive lesions than those with {sup 18}F-FDG-negative lesions (p < 0.05). Early recurrence (n=2) or early death (n=5) occurred more frequently in patients with {sup 18}F-FDG-positive lesions than in those with {sup 18}F-FDG-negative lesions (p < 0.05). The combined use of {sup 11}C-choline and {sup 18}F-FDG PET/CT detected HCC with high sensitivity. This approach appears to be of potential prognostic value and may facilitate the selection of patients for surgical resection or liver transplantation. (orig.)

  16. Clinical diagnosis value of CT manifestations for pulmonary fungal infections%CT表现对肺部真菌感染的临床诊断价值

    Institute of Scientific and Technical Information of China (English)

    贾策; 杨文鹃

    2012-01-01

    OBJECTIVE To probe into the clinical diagnosis value of CT manifestations for pulmonary fungal infections. METHODS From Jan. 2006 to Sep. 2011, 48 cases with pulmonary fungal infections in our hospital were selected for our study. All the patients underwent routine supine chest CT scan. The shapes and types of pulmonary lesions were statistically analyzed, and the relationship between CT classification and underlying diseases was analyzed. RESULTS CT imaging findings in 48 patients included diffuse, aspergilloma, consolidation and nodular. Diffuse were found in 19 cases, accounting for 39. 6%; aspergilloma in 13 cases, accounting for 27. 1% ; consolidation in 12 cases, accounting for 25. 0% t nodules in 4 cases, accounting for 8. 3%. In addition, for tuberculosis patients, CT images were mainly diffuse (63. 6%). For chronic bronchiectasis patients, CT images were mainly aspergilloma (72. 73%). For diabetic patients, CT images were mainly solidvariant (66. 7%) and nodules (33. 3%). For lung cancer patients, CT images were mainly diffuse (75. 0%). For HIV-infected patients, CT images were mainly diffuse (50. 0%) and consolidation(50. 0%). For patients without underlying diseases, CT images were dispersed. CONCLUSION CT images are of clinical diagnosis values for pulmonary fungal infections in patients and have certain characteristics.%目的 探讨CT影像学表现对肺部真菌感染患者临床诊断的价值.方法 选择2006年1月-2011年9月医院肺部真菌感染病例48例,所有患者均行胸部常规仰卧位CT平扫,对所有患者肺内病灶的形态及分型情况进行统计分析,并分析不同基础疾病与CT分型的关系.结果 48例患者CT影像表现主要分为弥散型、曲菌球型、实变型和结节型,其中弥散型19例,占39.6%;曲菌球型13例,占27.1%;实变型12例,占25.0%;结节型4例,占8.3%;另外,对于肺结核患者,CT影像主要为弥散型占63.6%;对于慢性支气管扩张患

  17. The predictive value of {sup 18}F-FDG PET/CT for assessing pathological response and survival in locally advanced rectal cancer after neoadjuvant radiochemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Leccisotti, Lucia; Stefanelli, Antonella; Giordano, Alessandro [Universita Cattolica del Sacro Cuore, Institute of Nuclear Medicine, Rome (Italy); Gambacorta, Maria Antonietta; Valentini, Vincenzo [Universita Cattolica del Sacro Cuore, Institute of Radiation Oncology, Rome (Italy); De Waure, Chiara [Universita Cattolica del Sacro Cuore, Institute of Public Health, Roma (Italy); Barbaro, Brunella [Universita Cattolica del Sacro Cuore, Institute of Radiology, Rome (Italy); Vecchio, Fabio Maria [Universita Cattolica del Sacro Cuore, Institute of Pathology, Rome (Italy); Coco, Claudio; Persiani, Roberto; Crucitti, Antonio; Tortorelli, Antonino Pio [Universita Cattolica del Sacro Cuore, Department of Surgical Sciences, Rome (Italy)

    2015-04-01

    To evaluate whether metabolic changes in the primary tumour during and after preoperative radiochemotherapy (RCT) can predict the histopathological response in patients with locally advanced rectal cancer as well as disease-free survival (DFS) and overall survival (OS). Consecutive patients with cT2-4 N0-2 rectal adenocarcinoma were included. {sup 18}F-FDG PET/CT was performed at baseline, at the end of the second week of RCT (early PET/CT) and before surgery (late PET/CT). The PET/CT results were compared with histopathological data (ypT0 N0 vs. ypT1-4 N0-2 as well as TRG1 vs.TRG2-5) and survival. The study included 126 patients. Among 124 patients in whom TNM classification was available, 28 (22.6 %) were ypT0 N0, and among all 126 patients, 31 (24.6 %) were TRG1. The areas under the curve of the early response index (RI) for identifying non-complete pathological response (non-cPR) were 0.74 (95 % CI 0.61 - 0.87) for ypT1-4 N0-2 patients and 0.75 (95 % CI 0.62 - 0.88) for TRG2-5 patients. The optimal cut-off for differentiating patients with non-cPR and cPR was found to be a reduction of 61.2 % (83.1 % sensitivity and 65 % specificity in ypT1-4 N0-2 patients; 85.4 % sensitivity and 65.2 % specificity in TRG2-5 patients). The optimal cut-off for late RI could not be found. The qualitative analysis of images obtained after RCT demonstrated 81.5 % sensitivity and 61.3 % specificity in predicting TR