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Sample records for disease ct perfusion

  1. Correlation of CT perfusion and CT volumetry in patients with Alzheimers disease

    International Nuclear Information System (INIS)

    Czarnecka, A.; Zimny, A.; Sasiadek, M.

    2010-01-01

    Background: Both brain atrophy and decrease of perfusion are observed in dementive diseases. The aim of the study was to correlate the results of brain perfusion CT (pCT) and CT volumetry in patients with Alzheimers disease (AD). Material/Methods: Forty-eight patients with AD (mean age of 71.3 years) underwent brain pCT and CT volumetry. The pCT was performed at the level of basal ganglia after the injection of contrast medium (50 ml, 4 ml/sec.) with serial scanning (delay 7 sec, 50 scans, 1 scan/sec). Volumetric measurements were carried out on the basis of source images, with the use of a dedicated CT software combined with manual outlining of the regions of interest in extracerebral and intraventricular CSF spaces. Perfusion parameters of the cerebral blood flow (CBF) and cerebral blood volume (CBV) from the grey matter of frontal and temporal as well as basal ganglia were compared statistically with the volumetric measurements of frontal and temporal cortical atrophy as well as subcortical atrophy. Results: A statistically significant positive correlation was found between the values of CBF and CBV in the basal ganglia and the volumes of the lateral and third ventricles. The comparison of CBF and CBV results with the volumetric measurements in the areas of the frontal and temporal lobes showed mostly negative correlations, but none of them was of statistical significance. Conclusions: In patients with AD, the degree of cortical atrophy is not correlated with the decrease of perfusion in the grey matter and subcortical atrophy is not correlated with the decrease of perfusion in the basal ganglia region. It suggests that functional and structural changes in AD are not related to each other. (authors)

  2. CT Perfusion of the Head

    Science.gov (United States)

    ... Site Index A-Z CT Perfusion of the Head Computed tomography (CT) perfusion of the head uses ... the Head? What is CT Perfusion of the Head? Computed tomography (CT) perfusion imaging shows which areas ...

  3. CT perfusion imaging for childhood moyamoya disease before and after surgical revascularization

    OpenAIRE

    Sakamoto, Shigeyuki; Ohba, Shinji; Shibukawa, Masaaki; Kiura, Yoshihiro; Arita, Kazunori; Kurisu, Kaoru

    2006-01-01

    Moyamoya disease is a progressive occlusive disease of the circle of Willis with prominent collateral arterial formation. We report on a 12-year-old girl with moyamoya disease presenting with transient ischemic attacks (TIAs). Surgical indirect revascularization was performed. The patient did not suffer further TIAs at 12 month follow-up. Pre and postoperative cerebral perfusion were studied in quantitative single photon emission computerized tomography (SPECT) and CT perfusion imaging. CT pe...

  4. Characteristics of cerebral hemodynamics assessed by CT perfusion in moyamoya disease.

    Science.gov (United States)

    Sasagawa, Ayaka; Mikami, Takeshi; Hirano, Toru; Akiyama, Yukinori; Mikuni, Nobuhiro

    2018-01-01

    Due to the recent development of multidetector row computed tomography (CT), hemodynamic parameters can now be conveniently obtained with CT perfusion. The purpose of this study is to characterize the hemodynamic parameters of CT perfusion in moyamoya disease, and to discuss the differences in collateral circulation between moyamoya disease and atherosclerotic disease. A total of 16 hemispheric sides of 15 patients with moyamoya disease and 10 hemispheric sides of 9 patients with atherosclerotic disease who underwent bypass surgery were included. CT perfusion was performed with 123 I-IMP SPECT. Cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) values obtained by CT perfusion using standard singular value decomposition as the deconvolution algorithm in moyamoya disease were calculated. Preoperative values of these parameters were compared with those of atherosclerotic disease. Then, the postoperative changes of these parameters were analyzed. In the impaired side, CBF as measured by CT perfusion was correlated with that measured by 123 I-IMP SPECT. In moyamoya disease, CBV as measured by CT perfusion was significantly increased compared to in atherosclerotic disease, yet CBF was significantly decreased in atherosclerotic disease. Postoperatively, the asymmetry ratios of MTT were significantly improved, especially in atherosclerotic disease compared with moyamoya disease. On CT perfusion, the parameters included transit time and arrival time. CBV increase in moyamoya disease and postoperative improvement of MTT, especially in atherosclerotic disease, were unique characteristics in each. This might be due to the difference of collateral circulation and compensatory mechanisms between moyamoya disease and atherosclerotic disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Dynamic CT myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-10-15

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

  6. Myocardial CT perfusion imaging and SPECT for the diagnosis of coronary artery disease

    DEFF Research Database (Denmark)

    George, Richard T; Mehra, Vishal C; Chen, Marcus Y

    2014-01-01

    PURPOSE: To compare the diagnostic performance of myocardial computed tomographic (CT) perfusion imaging and single photon emission computed tomography (SPECT) perfusion imaging in the diagnosis of anatomically significant coronary artery disease (CAD) as depicted at invasive coronary angiography....... MATERIALS AND METHODS: This study was approved by the institutional review board. Written informed consent was obtained from all patients. Sixteen centers enrolled 381 patients from November 2009 to July 2011. Patients underwent rest and adenosine stress CT perfusion imaging and rest and either exercise...... or pharmacologic stress SPECT before and within 60 days of coronary angiography. Images from CT perfusion imaging, SPECT, and coronary angiography were interpreted at blinded, independent core laboratories. The primary diagnostic parameter was the area under the receiver operating characteristic curve (Az...

  7. Foot CT perfusion in patients with peripheral arterial occlusive disease (PAOD): A feasibility study

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    Iezzi, R., E-mail: roberto.iezzi@rm.unicatt.it [Department of Bioimaging and Radiological Sciences, Institute of Radiology, “A. Gemelli” Hospital – Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Santoro, M., E-mail: dott.santoromarco@gmail.com [Department of Bioimaging and Radiological Sciences, Institute of Radiology, “A. Gemelli” Hospital – Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Dattesi, R., E-mail: robertadattesi@gmail.com [Department of Bioimaging and Radiological Sciences, Institute of Radiology, “A. Gemelli” Hospital – Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); La Torre, M.F. [Department of Bioimaging and Radiological Sciences, Institute of Radiology, “A. Gemelli” Hospital – Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Tinelli, G., E-mail: tinelli@rm.unicatt.it [Department of Vascular Surgery, “A. Gemelli” Hospital – Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Snider, F., E-mail: fsnider@rm.unicatt.it [Department of Vascular Surgery, “A. Gemelli” Hospital – Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Bonomo, L., E-mail: lbonomo@rm.unicatt.it [Department of Bioimaging and Radiological Sciences, Institute of Radiology, “A. Gemelli” Hospital – Catholic University, L.go A Gemelli 8, 00168 Rome (Italy)

    2013-09-15

    Purpose: To prospectively assess the technical feasibility and reproducibility of quantitative foot perfusion multidetector-row computed tomography (MDCT) in patients with peripheral occlusive artery disease (PAOD) and to evaluate perfusion parameters changes after endovascular treatment. Materials and methods: Institutional review board approval and informed patient consent were obtained. 10 patients older than 65 years (mean 74.1 years, range 66–95 years) with PAOD and who were referred to our department for single-limb endovascular treatment were enrolled prospectively. All patients underwent foot CT perfusion examinations before and within 72 h after endovascular treatment. A 64-row CT lightspeed VCT scanner (GE Medical Systems) was used with acquisition of eight contiguous 5-mm reconstructed sections (60-s acquisition time; 40 mL Iomeprol 400 mgI/mL, @4 mL/s). Data were analyzed by two blinded readers using commercially available software to calculate perfusion parameters. Inter-observer and intra-observer agreement of perfusion CT analysis was assessed using Bland–Altman analyses and intra-class correlation coefficient (ICC). Changes in perfusion parameters after endovascular treatment were assessed using Wilcoxon's test. Results: Good inter-observer and intra-observer agreement was obtained in all patients. Good agreement was obtained for perfusion parameters for the untreated foot and in repeated studies. By comparing perfusion parameters in the treated foot, a significantly shorter mean transit time (MTT) was obtained. Conclusions: Foot CT perfusion is a feasible and reproducible technique. A significant decrease of MTT between pre- and post-revascularization suggests improved flow in the below-the-knee arteries.

  8. Coronary Artery Disease: Analysis of Diagnostic Performance of CT Perfusion and MR Perfusion Imaging in Comparison with Quantitative Coronary Angiography and SPECT-Multicenter Prospective Trial.

    Science.gov (United States)

    Rief, Matthias; Chen, Marcus Y; Vavere, Andrea L; Kendziora, Benjamin; Miller, Julie M; Bandettini, W Patricia; Cox, Christopher; George, Richard T; Lima, João; Di Carli, Marcelo; Plotkin, Michail; Zimmermann, Elke; Laule, Michael; Schlattmann, Peter; Arai, Andrew E; Dewey, Marc

    2018-02-01

    Purpose To compare the diagnostic performance of stress myocardial computed tomography (CT) perfusion with that of stress myocardial magnetic resonance (MR) perfusion imaging in the detection of coronary artery disease (CAD). Materials and Methods All patients gave written informed consent prior to inclusion in this institutional review board-approved study. This two-center substudy of the prospective Combined Noninvasive Coronary Angiography and Myocardial Perfusion Imaging Using 320-Detector Row Computed Tomography (CORE320) multicenter trial included 92 patients (mean age, 63.1 years ± 8.1 [standard deviation]; 73% male). All patients underwent perfusion CT and perfusion MR imaging with either adenosine or regadenoson stress. The predefined reference standards were combined quantitative coronary angiography (QCA) and single-photon emission CT (SPECT) or QCA alone. Results from coronary CT angiography were not included, and diagnostic performance was evaluated with the Mantel-Haenszel test stratified by disease status. Results The prevalence of CAD was 39% (36 of 92) according to QCA and SPECT and 64% (59 of 92) according to QCA alone. When compared with QCA and SPECT, per-patient diagnostic accuracy of perfusion CT and perfusion MR imaging was 63% (58 of 92) and 75% (69 of 92), respectively (P = .11); sensitivity was 92% (33 of 36) and 83% (30 of 36), respectively (P = .45); and specificity was 45% (25 of 56) and 70% (39 of 56), respectively (P CT perfusion and MR perfusion imaging was 82% (75 of 92) and 74% (68 of 92), respectively (P = .27); sensitivity was 90% (53 of 59) and 69% (41 of 59), respectively (P perfusion CT is similar to that of perfusion MR imaging in the detection of CAD. © RSNA, 2017 Online supplemental material is available for this article.

  9. Prognostic Value of Stress Dynamic Myocardial Perfusion CT in a Multicenter Population With Known or Suspected Coronary Artery Disease.

    Science.gov (United States)

    Meinel, Felix G; Pugliese, Francesca; Schoepf, U Joseph; Ebersberger, Ullrich; Wichmann, Julian L; Lo, Gladys G; Choe, Yeon Hyeon; Wang, Yining; Segreto, Sabrina; Bamberg, Fabian; De Cecco, Carlo N

    2017-04-01

    The purpose of this study was to determine the prognostic value of myocardial perfusion CT for major adverse cardiac events (MACE). Data from six centers in Asia, Europe, and North America on 144 patients with known or suspected coronary artery disease who had undergone coronary CT angiography (CCTA) and dynamic myocardial perfusion CT with a dual-source CT system were analyzed. CCTA studies were acquired at rest. Dynamic myocardial perfusion CT was performed under vasodilator stress. CCTA data were evaluated for the presence of coronary artery stenosis (≥ 50% luminal narrowing) on a per-vessel basis. Myocardial perfusion CT data were qualitatively evaluated for perfusion defects in each vessel territory. Patient follow-up was performed 6, 12, and 18 months after imaging. The prognostic value of CT findings was assessed with Kaplan-Meier statistics and the multivariate Cox proportional hazards regression model. According to the CCTA findings, 62 of 144 patients (43.1%) had at least one 50% or greater stenosis. According to the myocardial perfusion CT findings, 51 patients (35.4%) had one or more perfusion defects. Patients with at least one perfusion defect at myocardial perfusion CT were at increased risk of MACE (hazard ratio, 2.50; 95% CI, 1.34-4.65; p = 0.0040). This association remained significant after adjustment for age, sex, and clinical risk factors (hazard ratio, 2.41; 95% CI, 1.28-4.51; p = 0.0064) and after further adjustment for CCTA findings (hazard ratio, 2.03; 95% CI, 1.04-3.97; p = 0.0390). The number of territories with perfusion defects was strongly predictive of MACE with adjusted hazard ratios of 1.41, 3.44, and 4.76 for one, two, and three affected territories. In assessment for future MACE, myocardial perfusion CT has incremental predictive value over clinical risk factors and detection of coronary artery stenosis with CCTA.

  10. Contrast-enhanced CT- and MRI-based perfusion assessment for pulmonary diseases: basics and clinical applications.

    Science.gov (United States)

    Ohno, Yoshiharu; Koyama, Hisanobu; Lee, Ho Yun; Miura, Sachiko; Yoshikawa, Takeshi; Sugimura, Kazuro

    2016-01-01

    Assessment of regional pulmonary perfusion as well as nodule and tumor perfusions in various pulmonary diseases are currently performed by means of nuclear medicine studies requiring radioactive macroaggregates, dual-energy computed tomography (CT), and dynamic first-pass contrast-enhanced perfusion CT techniques and unenhanced and dynamic first-pass contrast enhanced perfusion magnetic resonance imaging (MRI), as well as time-resolved three-dimensional or four-dimensional contrast-enhanced magnetic resonance angiography (MRA). Perfusion scintigraphy, single-photon emission tomography (SPECT) and SPECT fused with CT have been established as clinically available scintigraphic methods; however, they are limited by perfusion information with poor spatial resolution and other shortcomings. Although positron emission tomography with 15O water can measure absolute pulmonary perfusion, it requires a cyclotron for generation of a tracer with an extremely short half-life (2 min), and can only be performed for academic purposes. Therefore, clinicians are concentrating their efforts on the application of CT-based and MRI-based quantitative and qualitative perfusion assessment to various pulmonary diseases. This review article covers 1) the basics of dual-energy CT and dynamic first-pass contrast-enhanced perfusion CT techniques, 2) the basics of time-resolved contrast-enhanced MRA and dynamic first-pass contrast-enhanced perfusion MRI, and 3) clinical applications of contrast-enhanced CT- and MRI-based perfusion assessment for patients with pulmonary nodule, lung cancer, and pulmonary vascular diseases. We believe that these new techniques can be useful in routine clinical practice for not only thoracic oncology patients, but also patients with different pulmonary vascular diseases.

  11. A new clinical tool for the quantification of myocardial CT perfusion imaging in patients with suspected Ischemic Heart Disease

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Muñoz, A.; Dux-Santoy Hurtado, L.; Rodriguez Palomares, J.L.; Piella Fenoy, G.

    2016-07-01

    In the clinical practice, the evaluation of myocardial perfusion by using Computed Tomography (CT) Imaging is usually performed visually or semi-quantitatively. The scarcity of quantitative perfusion data not always allows a proper diagnose of patients which are suspected of suffering from some diseases, such as Ischemic Heart Disease (IHD). In this work, a clinical tool for the automatic quantification of myocardial perfusion in patients with suspected IHD is proposed. Myocardial perfusion is assessed based on a combined diagnosis protocol (CT/CTP protocol) which involves the acquisition of two contrastenhanced CT images, one obtained at rest and another acquired under pharmacological stress. The clinical tool allows the automatic quantification of perfusion in different myocardial segments defined according to the 16-AHA-segmentation model of the left ventricle, by providing the mean of Hounsfield Units in those regions. Based on this analysis, the clinicians can compare the values at baseline and at hyperemia, and they can better determine hypoperfusion defects in patients with IHD. The validation of the clinical tool was performed by comparing automatic and manual perfusion measurements of 10 patients with suspected IHD who were previously assessed with Single Photon Emission Computed Tomography (SPECT) for perfusion analysis. A strong linear correlation was found between the automatic and manual results. Afterwards, perfusion defects obtained from CT/CTP protocol were compared to perfusion defects from SPECT, to assess the applicability of this clinical tool for the diagnosis of IHD. (Author)

  12. Monitoring Disease Activity in Patients with Aortitis and Chronic Periaortitis Undergoing Immunosuppressive Therapy by Perfusion CT.

    Science.gov (United States)

    Bier, Georg; Kurucay, Mustafa; Henes, Jörg; Xenitidis, Theodoros; Preibsch, Heike; Nikolaou, Konstantin; Horger, Marius

    2017-04-01

    To evaluate the role of perfusion CT for monitoring inflammatory activity in patients with aortitis and chronic periaortitis undergoing immunosuppressive therapy. Seventeen symptomatic patients (median age 68.5 years) who underwent perfusion-based computed tomography (CT) monitoring after diagnostic contrast-enhanced CT were retrospectively included in this study. Blood flow (BF), blood volume (BV), volume transfer constant (k-trans), time to peak, and mean transit time were determined by setting circular regions of interest in prominently thickened parts of the vessel wall or perfused surrounding tissue at sites where the perfusion CT color maps showed a maximum BF value. Differences in CT perfusion and, morphological parameters, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were tested for significance during therapy. In all patients BF and BV dropped at second perfusion CT (P perfusion CT parameters in aortitis and chronic periaortitis undergoing immunosuppressive therapy dropped at different extent after therapy. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  13. Quantitative assessment of pulmonary perfusion using dynamic contrast-enhanced CT in patients with chronic obstructive pulmonary disease: correlations with pulmonary function test and CT volumetric parameters.

    Science.gov (United States)

    Guan, Yu; Xia, Yi; Fan, Li; Liu, Shi-yuan; Yu, Hong; Li, Bin; Zhao, Li-ming; Li, Bing

    2015-05-01

    Pulmonary function test (PFT) is commonly used to help diagnose chronic obstructive pulmonary disease (COPD) and other lung diseases. However, it cannot be used to evaluate regional function and morphological abnormalities. To quantitatively evaluate pulmonary perfusion imaging using dynamic contrast-enhanced (DCE) computed tomography (CT) and observe its correlations with PFT and CT volumetric parameters in COPD patients. PFT and CT pulmonary perfusion examination were performed in 63 COPD patients. Perfusion defects were quantitated by calculating the CT value ratio (RHU) between perfusion defects (HUdefect) and normal lung (HUnormal). Volumetric CT data were used to calculate emphysema index (EI), total lung volume (TLV), and total emphysema volume (TEV). Emphysematous parenchyma was defined as the threshold of lung area lower than -950 HU. Correlations between RHU and TLV, TEV, EI, and PFT were assessed using Spearman correlation analysis. The positive rate of perfusion defects on CT perfusion images was higher than that of emphysema on CT mask images (χ(2) = 17.027, P < 0.001). The Spearman correlation test showed that RHU was positively correlated with FEV1 (R = 0.59, P < 0.001), FEV1% Predicted (R = 0.61, P < 0.001), FVC (R = 0.47, P = 0.002), and FEV1/FVC (R = 0.65, P < 0.001), and negatively correlated with EI (R = -0.67, P < 0.001). CT perfusion imaging is more sensitive in detecting emphysema that is inconspicuous on CT images. RHU is correlated with PFT and CT volumetric parameters, suggesting that it is more sensitive in detecting early COPD changes and may prove to be a potential predictor of focal lung function. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  14. Perfusion CT in acute stroke

    International Nuclear Information System (INIS)

    Eckert, Bernd; Roether, Joachim; Fiehler, Jens; Thomalla, Goetz

    2015-01-01

    Modern multislice CT scanners enable multimodal protocols including non-enhanced CT, CT angiography, and CT perfusion. A 64-slice CT scanner provides 4-cm coverage. To cover the whole brain, a 128 - 256-slice scanner is needed. The use of perfusion CT requires an optimized scan protocol in order to reduce exposure to radiation. As compared to non-enhanced CT and CT angiography, the use of CT perfusion increases detection rates of cerebral ischemia, especially small cortical ischemic lesions, while the detection of lacunar and infratentorial stroke lesions remains limited. Perfusion CT enables estimation of collateral flow in acute occlusion of large intra- or extracranial arteries. Currently, no established reliable thresholds are available for determining infarct core and penumbral tissue by CT perfusion. Moreover, perfusion parameters depend on the processing algorithms and the software used for calculation. However, a number of studies point towards a reduction of cerebral blood volume (CBV) below 2 ml/100 g as a critical threshold that identifies infarct core. Large CBV lesions are associated with poor outcome even in the context of recanalization. The extent of early ischemic signs on non-enhanced CT remains the main parameter from CT imaging to guide acute reperfusion treatment. Nevertheless, perfusion CT increases diagnostic and therapeutic certainty in the acute setting. Similar to stroke MRI, perfusion CT enables the identification of tissue at risk of infarction by the mismatch between infarct core and the larger area of critical hypoperfusion. Further insights into the validity of perfusion parameters are expected from ongoing trials of mechanical thrombectomy in stroke.

  15. Whole-brain CT perfusion and CT angiography assessment of Moyamoya disease before and after surgical revascularization: preliminary study with 256-slice CT.

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    Full Text Available BACKGROUND/AIMS: The 256-slice CT enables the entire brain to be scanned in a single examination. We evaluated the application of 256-slice whole-brain CT perfusion (CTP in determining graft patency as well as investigating cerebral hemodynamic changes in Moyamoya disease before and after surgical revascularization. METHODS: Thirty-nine cases of Moyamoya disease were evaluated before and after surgical revascularization with 256-slice CT. Whole-brain perfusion images and dynamic 3D CT angiographic images generated from perfusion source data were obtained in all patients. Cerebral blood flow (CBF, cerebral blood volume (CBV, time to peak (TTP and mean transit time (MTT of one hemisphere in the region of middle cerebral artery (MCA distribution and contralateral mirroring areas were measured. Relative CTP values (rCBF, rCBV, rTTP, rMTT were also obtained. Differences in pre- and post- operation perfusion CT values were assessed with paired t test or matched-pairs signed-ranks test. RESULTS: Preoperative CBF, MTT and TTP of potential surgical side were significantly different from those of contralateral side (P<0.01 for all. All graft patencies were displayed using the 3D-CTA images. Postoperative CBF, rCBF and rCBV values of surgical side in the region of MCA were significantly higher than those before operation (P<0.01 for all. Postoperative MTT, TTP, rMTT and rTTP values of the surgical side in the region of MCA were significantly lower than those before operation (P<0.05 for all. CONCLUSION: The 256-slice whole-brain CTP can be used to evaluate cerebral hemodynamic changes in Moyamoya disease before and after surgery and the 3D-CTA is useful for assessing the abnormalities of intracranial arteries and graft patencies.

  16. Whole-brain CT perfusion and CT angiography assessment of Moyamoya disease before and after surgical revascularization: preliminary study with 256-slice CT.

    Science.gov (United States)

    Zhang, Jun; Wang, Jianhong; Geng, Daoying; Li, Yuxin; Song, Donglei; Gu, Yuxiang

    2013-01-01

    The 256-slice CT enables the entire brain to be scanned in a single examination. We evaluated the application of 256-slice whole-brain CT perfusion (CTP) in determining graft patency as well as investigating cerebral hemodynamic changes in Moyamoya disease before and after surgical revascularization. Thirty-nine cases of Moyamoya disease were evaluated before and after surgical revascularization with 256-slice CT. Whole-brain perfusion images and dynamic 3D CT angiographic images generated from perfusion source data were obtained in all patients. Cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP) and mean transit time (MTT) of one hemisphere in the region of middle cerebral artery (MCA) distribution and contralateral mirroring areas were measured. Relative CTP values (rCBF, rCBV, rTTP, rMTT) were also obtained. Differences in pre- and post- operation perfusion CT values were assessed with paired t test or matched-pairs signed-ranks test. Preoperative CBF, MTT and TTP of potential surgical side were significantly different from those of contralateral side (P<0.01 for all). All graft patencies were displayed using the 3D-CTA images. Postoperative CBF, rCBF and rCBV values of surgical side in the region of MCA were significantly higher than those before operation (P<0.01 for all). Postoperative MTT, TTP, rMTT and rTTP values of the surgical side in the region of MCA were significantly lower than those before operation (P<0.05 for all). The 256-slice whole-brain CTP can be used to evaluate cerebral hemodynamic changes in Moyamoya disease before and after surgery and the 3D-CTA is useful for assessing the abnormalities of intracranial arteries and graft patencies.

  17. Comprehensive Assessment of Coronary Artery Disease by Using First-Pass Analysis Dynamic CT Perfusion: Validation in a Swine Model.

    Science.gov (United States)

    Hubbard, Logan; Lipinski, Jerry; Ziemer, Benjamin; Malkasian, Shant; Sadeghi, Bahman; Javan, Hanna; Groves, Elliott M; Dertli, Brian; Molloi, Sabee

    2018-01-01

    Purpose To retrospectively validate a first-pass analysis (FPA) technique that combines computed tomographic (CT) angiography and dynamic CT perfusion measurement into one low-dose examination. Materials and Methods The study was approved by the animal care committee. The FPA technique was retrospectively validated in six swine (mean weight, 37.3 kg ± 7.5 [standard deviation]) between April 2015 and October 2016. Four to five intermediate-severity stenoses were generated in the left anterior descending artery (LAD), and 20 contrast material-enhanced volume scans were acquired per stenosis. All volume scans were used for maximum slope model (MSM) perfusion measurement, but only two volume scans were used for FPA perfusion measurement. Perfusion measurements in the LAD, left circumflex artery (LCx), right coronary artery, and all three coronary arteries combined were compared with microsphere perfusion measurements by using regression, root-mean-square error, root-mean-square deviation, Lin concordance correlation, and diagnostic outcomes analysis. The CT dose index and size-specific dose estimate per two-volume FPA perfusion measurement were also determined. Results FPA and MSM perfusion measurements (P FPA and P MSM ) in all three coronary arteries combined were related to reference standard microsphere perfusion measurements (P MICRO ), as follows: P FPA_COMBINED = 1.02 P MICRO_COMBINED + 0.11 (r = 0.96) and P MSM_COMBINED = 0.28 P MICRO_COMBINED + 0.23 (r = 0.89). The CT dose index and size-specific dose estimate per two-volume FPA perfusion measurement were 10.8 and 17.8 mGy, respectively. Conclusion The FPA technique was retrospectively validated in a swine model and has the potential to be used for accurate, low-dose vessel-specific morphologic and physiologic assessment of coronary artery disease. © RSNA, 2017.

  18. CT perfusion: the clinical application in the diagnosis of breast diseases

    International Nuclear Information System (INIS)

    Ye Zhaoxiang; Song Xiuyu; Xiao Jianyu

    2005-01-01

    Objective: To assess the CT perfusion characteristics of breast diseases. Methods: Twenty-two patients with fibroadenoma accompanied with cyst (n=1), other benign diseases (n=5), and carcinomas (n=16) underwent breast CT scan. CT perfusion was performed for breast with cine mode (0.5 s per rotation ) on a multislice CT scanner, 120 kV, 60 mA, 4 x 5 mm collimation. Contrast injection was done by using 50 ml nonionic contrast agent (300 mg I/ml ), at a flow rate of 4 ml/s with a power injector, 5 seconds delay, and data acquisition lasted for 50 seconds. These data were processed on a GE AW 4.1 workstation using perfusion 3 software package, and the mean BF, BV, MTT and PS were measured and statistically analyzed. Results: The mean BF, BV, MTT and PS in carcinoma were (33.55 ± 28.40) ml·min -1 ·100 g -1 , (5.60±3.08) ml/100 g, (15.37±6.41) s, (18.71±10.42) ml· min -1 ·100 g -1 . The mean BF, BV, MTT and PS in contralateral normal breast of carcinoma were (10.36 ± 9.44) ml·min -1 ·100 g -1 , (0.70±0.22) ml/100 g, (13.55 ± 7.27) s, (1.54±1.74) ml·min -1 ·100 g -1 . The mean BF, BV, and PS between carcinoma and normal breast were statistically significant (P 0.05). The mean BF, BV, MTT and PS in fibroadenoma were (62.57 ± 19.62) ml·min -1 ·100 g -1 , (7.37 ±1.30) ml/100 g, (11.24 ± 3.34) s, (27.63 ± 3.87) ml·min -1 ·100 g -1 . The mean PS between carcinoma and fibroadenoma was statistically significant (P 0.05). The mean BF, BV, MTT and PS in benign lesion were (7.65 ± 10.24) ml·min -1 ·100 g -1 , (1.23 ± 0.97) ml/100 g, (14.94 ± 10.68) s, (1.81 ± 1.72) ml·min -1 ·100 g -1 . The mean BF, BV, and PS between carcinoma and benign lesion were statistically significant (P 0.05). Conclusion: MSCT perfusion may reflect the features of breast diseases, and provide valuable hemodynamic message. These parameters have a value in diagnosis of breast diseases and are helpful for differential diagnosis. (authors)

  19. Stress Myocardial Perfusion CT in Patients Suspected of Having Coronary Artery Disease: Visual and Quantitative Analysis-Validation by Using Fractional Flow Reserve.

    Science.gov (United States)

    Yang, Dong Hyun; Kim, Young-Hak; Roh, Jae-Hyung; Kang, Joon-Won; Han, Dongjin; Jung, Joonho; Kim, Namkug; Lee, Jung Bok; Ahn, Jung-Min; Lee, Jong-Young; Park, Duk-Woo; Kang, Soo-Jin; Lee, Seung-Whan; Lee, Cheol Whan; Park, Seong-Wook; Park, Seung-Jung; Lim, Tae-Hwan

    2015-09-01

    To assess the diagnostic accuracy of stress myocardial perfusion computed tomography (CT) by using visual and quantitative analytic methods in patients with coronary artery disease, with fractional flow reserve (FFR) as a reference standard. The institutional review board approved the study, and written informed consent was obtained from all patients. The diagnostic accuracy of myocardial perfusion CT was assessed for 75 patients who underwent myocardial perfusion CT and conventional coronary angiography with reference to hemodynamically significant stenosis, defined as the presence of an FFR of 0.8 or less or an angiographically severe (≥90%) stenosis. Results of quantitative analysis of myocardial perfusion CT data were compared with those of visual analysis by using areas under the receiver operating characteristic curve (AUCs). Among the 75 patients and 210 epicardial arteries, 61 patients (81%) with 86 arteries (41%) had hemodynamically significant stenosis. The per-patient sensitivity and specificity of the visual assessment of myocardial perfusion CT data for all patients were 89% and 86%, respectively. At per-vessel analysis, the sensitivities and specificities, respectively, of myocardial perfusion CT were 80% and 95% for all vessels, 85% and 100% for 63 vessels with severe coronary calcification (defined as an Agatston score > 400), and 76% and 91% for 56 vessels in patients with multivessel disease. In severely calcified vessels, visual assessment of myocardial perfusion CT data in combination with CT angiography provided incremental value over CT angiography alone for the detection of myocardial ischemia (integrated discrimination improvement index, 0.38; P perfusion ratio had a lower AUC than visual analysis of myocardial perfusion CT (0.759 vs 0.877, P = .002). Stress myocardial perfusion CT provides incremental value over CT angiography in patients with a high calcium score for the detection of myocardial ischemia as defined by FFR.

  20. 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

  1. Myocardial perfusion imaging with dual energy CT

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Spandorfer, Adam; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States)

    2016-10-15

    Highlights: • Stress dual-energy sCTMPI offers the possibility to directly detect the presence of myocardial perfusion defects. • Stress dual-energy sCTMPI allows differentiating between reversible and fixed myocardial perfusion defects. • The combination of coronary CT angiography and dual-energy sCTMPI can improve the ability of CT to detect hemodynamically relevant coronary artery disease. - Abstract: Dual-energy CT (DECT) enables simultaneous use of two different tube voltages, thus different x-ray absorption characteristics are acquired in the same anatomic location with two different X-ray spectra. The various DECT techniques allow material decomposition and mapping of the iodine distribution within the myocardium. Static dual-energy myocardial perfusion imaging (sCTMPI) using pharmacological stress agents demonstrate myocardial ischemia by single snapshot images of myocardial iodine distribution. sCTMPI gives incremental values to coronary artery stenosis detected on coronary CT angiography (CCTA) by showing consequent reversible or fixed myocardial perfusion defects. The comprehensive acquisition of CCTA and sCTMPI offers extensive morphological and functional evaluation of coronary artery disease. Recent studies have revealed that dual-energy sCTMPI shows promising diagnostic accuracy for the detection of hemodynamically significant coronary artery disease compared to single-photon emission computed tomography, invasive coronary angiography, and cardiac MRI. The aim of this review is to present currently available DECT techniques for static myocardial perfusion imaging and recent clinical applications and ongoing investigations.

  2. Computed Tomography (CT) Perfusion in Abdominal Cancer

    DEFF Research Database (Denmark)

    Hansen, Martin Lundsgaard; Norling, Rikke; Lauridsen, Carsten

    2013-01-01

    for assessment of vascularity. CT perfusion has also been used for tumor characterization, staging of disease, response evaluation of newer drugs targeted towards angiogenesis and as a method for early detection of recurrence after radiation and embolization. There are several software solutions available...

  3. Perfusion CT imaging of the liver: review of clinical applications

    Science.gov (United States)

    Oğul, Hayri; Kantarcı, Mecit; Genç, Berhan; Pirimoğlu, Berhan; Çullu, Neşat; Kızrak, Yeşim; Yılmaz, Ömer; Karabulut, Nevzat

    2014-01-01

    Perfusion computed tomography (CT) has a great potential for determining hepatic and portal blood flow; it offers the advantages of quantitative determination of lesion hemodynamics, distinguishing malignant and benign processes, as well as providing morphological data. Many studies have reported the use of this method in the assessment of hepatic tumors, hepatic fibrosis associated with chronic liver disease, treatment response following radiotherapy and chemotherapy, and hepatic perfusion changes after radiological or surgical interventions. The main goal of liver perfusion imaging is to improve the accuracy in the characterization of liver disorders. In this study, we reviewed the clinical application of perfusion CT in various hepatic diseases. PMID:24834487

  4. Myocardial CT perfusion imaging for ischemia detection

    Science.gov (United States)

    Capunay, Carlos

    2017-01-01

    Coronary computed tomography angiography (CCTA) plays an important role in many specific scenarios such as in symptomatic patients with intermediate pretest of coronary artery disease (CAD), as well as in the triage of patients with acute chest pain with TIMI risk ≤2. However, it cannot detect the presence of associated ischemia, which is critical for clinical decision making among patients with moderate to severe stenosis. Although functional information can be obtained with different non-invasive tools, cardiac CT is the unique modality that can perform a comprehensive evaluation of coronary anatomy plus the functional significance of lesions. Myocardial CT perfusion (CTP) can be performed with different approaches such as static and dynamic CTP. In addition, static CTP can be performed using single energy CT (SECT) or dual energy CT (DECT). In this review, we will discuss the technical parameters and the available clinical evidence of static CTP using both SECT and DECT. PMID:28540208

  5. Myocardial CT Perfusion Imaging and SPECT for the Diagnosis of Coronary Artery Disease: A Head-to-Head Comparison from the CORE320 Multicenter Diagnostic Performance Study

    Science.gov (United States)

    Mehra, Vishal C.; Chen, Marcus Y.; Kitagawa, Kakuya; Arbab-Zadeh, Armin; Miller, Julie M.; Matheson, Matthew B.; Vavere, Andrea L.; Kofoed, Klaus F.; Rochitte, Carlos E.; Dewey, Marc; Yaw, Tan S.; Niinuma, Hiroyuki; Brenner, Winfried; Cox, Christopher; Clouse, Melvin E.; Lima, João A. C.; Di Carli, Marcelo

    2014-01-01

    Purpose To compare the diagnostic performance of myocardial computed tomographic (CT) perfusion imaging and single photon emission computed tomography (SPECT) perfusion imaging in the diagnosis of anatomically significant coronary artery disease (CAD) as depicted at invasive coronary angiography. Materials and Methods This study was approved by the institutional review board. Written informed consent was obtained from all patients. Sixteen centers enrolled 381 patients from November 2009 to July 2011. Patients underwent rest and adenosine stress CT perfusion imaging and rest and either exercise or pharmacologic stress SPECT before and within 60 days of coronary angiography. Images from CT perfusion imaging, SPECT, and coronary angiography were interpreted at blinded, independent core laboratories. The primary diagnostic parameter was the area under the receiver operating characteristic curve (Az). Sensitivity and specificity were calculated with use of prespecified cutoffs. The reference standard was a stenosis of at least 50% at coronary angiography as determined with quantitative methods. Results CAD was diagnosed in 229 of the 381 patients (60%). The per-patient sensitivity and specificity for the diagnosis of CAD (stenosis ≥50%) were 88% (202 of 229 patients) and 55% (83 of 152 patients), respectively, for CT perfusion imaging and 62% (143 of 229 patients) and 67% (102 of 152 patients) for SPECT, with Az values of 0.78 (95% confidence interval: 0.74, 0.82) and 0.69 (95% confidence interval: 0.64, 0.74) (P = .001). The sensitivity of CT perfusion imaging for single- and multivessel CAD was higher than that of SPECT, with sensitivities for left main, three-vessel, two-vessel, and one-vessel disease of 92%, 92%, 89%, and 83%, respectively, for CT perfusion imaging and 75%, 79%, 68%, and 41%, respectively, for SPECT. Conclusion The overall performance of myocardial CT perfusion imaging in the diagnosis of anatomic CAD (stenosis ≥50%), as demonstrated with the

  6. Absolute Versus Relative Myocardial Blood Flow by Dynamic CT Myocardial Perfusion Imaging in Patients With Anatomic Coronary Artery Disease

    NARCIS (Netherlands)

    Wichmann, Julian L.; Meinel, Felix G.; Schoepf, U. Joseph; Lo, Gladys G.; Choe, Yeon Hyeon; Wang, Yining; Vliegenthart, Rozemarijn; Varga-Szemes, Akos; Muscogiuri, Giuseppe; Cannao, Paola M.; De Cecco, Carlo N.

    OBJECTIVE. The purpose of this study was to evaluate differences in the diagnostic accuracy of absolute and relative territorial myocardial blood flow (MBF) derived from stress dynamic CT myocardial perfusion imaging (MPI) for the detection of significant coronary artery stenosis. MATERIALS AND

  7. Patient satisfaction with coronary CT angiography, myocardial CT perfusion, myocardial perfusion MRI, SPECT myocardial perfusion imaging and conventional coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Feger, S.; Rief, M.; Zimmermann, E.; Richter, F.; Roehle, R. [Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Humboldt-Universitaet zu Berlin, Berlin (Germany); Dewey, M. [Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Humboldt-Universitaet zu Berlin, Berlin (Germany); Institut fuer Radiologie, Berlin (Germany); Schoenenberger, E. [Medizinische Hochschule Hannover, Department of Medicine, Hannover (Germany)

    2015-07-15

    To evaluate patient acceptance of noninvasive imaging tests for detection of coronary artery disease (CAD), including single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI), stress perfusion magnetic resonance imaging (MRI), coronary CT angiography (CTA) in combination with CT myocardial stress perfusion (CTP), and conventional coronary angiography (CCA). Intraindividual comparison of perception of 48 patients from the CORE320 multicentre multinational study who underwent rest and stress SPECT-MPI with a technetium-based tracer, combined CTA and CTP (both with contrast agent, CTP with adenosine), MRI, and CCA. The analysis was performed by using a validated questionnaire. Patients had significantly more concern prior to CCA than before CTA/CTP (p < 0.001). CTA/CTP was also rated as more comfortable than SPECT-MPI (p = 0.001). Overall satisfaction with CT was superior to that of MRI (p = 0.007). More patients preferred CT (46 %; p < 0.001) as a future diagnostic test. Regarding combined CTA/CTP, CTP was characterised by higher pain levels and an increased frequency of angina pectoris during the examination (p < 0.001). Subgroup analysis showed a higher degree of pain during SPECT-MPI with adenosine stress compared to physical exercise (p = 0.016). All noninvasive cardiac imaging tests are well accepted by patients, with CT being the preferred examination. (orig.)

  8. Diagnostic performance of coronary CT angiography, stress dual-energy CT perfusion, and stress perfusion single-photon emission computed tomography for coronary artery disease: Comparison with combined invasive coronary angiography and stress perfusion cardiac MRI

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hyun Woo; Ko, Sung Min; Hwang, Hweung Kon; So, Young; Yi, Jeong Geun [Konkuk University Medical Center, Research Institute of Biomedical Science, Konkuk University School of Medicine, Seoul (Korea, Republic of); Lee, Eun Jeong [Dept. of Nuclear Medicine, Seoul Medical Center, Seoul (Korea, Republic of)

    2017-06-15

    To investigate the diagnostic performance of coronary computed tomography angiography (CCTA), stress dual-energy computed tomography perfusion (DE-CTP), stress perfusion single-photon emission computed tomography (SPECT), and the combinations of CCTA with myocardial perfusion imaging (CCTA + DE-CTP and CCTA + SPECT) for identifying coronary artery stenosis that causes myocardial hypoperfusion. Combined invasive coronary angiography (ICA) and stress perfusion cardiac magnetic resonance (SP-CMR) imaging are used as the reference standard. We retrospectively reviewed the records of 25 patients with suspected coronary artery disease, who underwent CCTA, DE-CTP, SPECT, SP-CMR, and ICA. The reference standard was defined as ≥ 50% stenosis by ICA, with a corresponding myocardial hypoperfusion on SP-CMR. For per-vascular territory analysis, the sensitivities of CCTA, DE-CTP, SPECT, CCTA + DE-CTP, and CCTA + SPECT were 96, 96, 68, 93, and 68%, respectively, and specificities were 72, 75, 89, 85, and 94%, respectively. The areas under the receiver operating characteristic curve (AUCs) were 0.84 ± 0.05, 0.85 ± 0.05, 0.79 ± 0.06, 0.89 ± 0.04, and 0.81 ± 0.06, respectively. For per-patient analysis, the sensitivities of CCTA, DE-CTP, SPECT, CCTA + DE-CTP, and CCTA + SPECT were 100, 100, 89, 100, and 83%, respectively; the specificities were 14, 43, 57, 43, and 57%, respectively; and the AUCs were 0.57 ± 0.13, 0.71 ± 0.11, 0.73 ± 0.11, 0.71 ± 0.11, and 0.70 ± 0.11, respectively. The combination of CCTA and DE-CTP enhances specificity without a loss of sensitivity for detecting hemodynamically significant coronary artery stenosis, as defined by combined ICA and SP-CMR.

  9. Diagnostic Performance of Coronary CT Angiography, Stress Dual-Energy CT Perfusion, and Stress Perfusion Single-Photon Emission Computed Tomography for Coronary Artery Disease: Comparison with Combined Invasive Coronary Angiography and Stress Perfusion Cardiac MRI.

    Science.gov (United States)

    Chung, Hyun Woo; Ko, Sung Min; Hwang, Hweung Kon; So, Young; Yi, Jeong Geun; Lee, Eun Jeong

    2017-01-01

    To investigate the diagnostic performance of coronary computed tomography angiography (CCTA), stress dual-energy computed tomography perfusion (DE-CTP), stress perfusion single-photon emission computed tomography (SPECT), and the combinations of CCTA with myocardial perfusion imaging (CCTA + DE-CTP and CCTA + SPECT) for identifying coronary artery stenosis that causes myocardial hypoperfusion. Combined invasive coronary angiography (ICA) and stress perfusion cardiac magnetic resonance (SP-CMR) imaging are used as the reference standard. We retrospectively reviewed the records of 25 patients with suspected coronary artery disease, who underwent CCTA, DE-CTP, SPECT, SP-CMR, and ICA. The reference standard was defined as ≥ 50% stenosis by ICA, with a corresponding myocardial hypoperfusion on SP-CMR. For per-vascular territory analysis, the sensitivities of CCTA, DE-CTP, SPECT, CCTA + DE-CTP, and CCTA + SPECT were 96, 96, 68, 93, and 68%, respectively, and specificities were 72, 75, 89, 85, and 94%, respectively. The areas under the receiver operating characteristic curve (AUCs) were 0.84 ± 0.05, 0.85 ± 0.05, 0.79 ± 0.06, 0.89 ± 0.04, and 0.81 ± 0.06, respectively. For per-patient analysis, the sensitivities of CCTA, DE-CTP, SPECT, CCTA + DE-CTP, and CCTA + SPECT were 100, 100, 89, 100, and 83%, respectively; the specificities were 14, 43, 57, 43, and 57%, respectively; and the AUCs were 0.57 ± 0.13, 0.71 ± 0.11, 0.73 ± 0.11, 0.71 ± 0.11, and 0.70 ± 0.11, respectively. The combination of CCTA and DE-CTP enhances specificity without a loss of sensitivity for detecting hemodynamically significant coronary artery stenosis, as defined by combined ICA and SP-CMR.

  10. Comprehensive Cardiac CT With Myocardial Perfusion Imaging Versus Functional Testing in Suspected Coronary Artery Disease: The Multicenter, Randomized CRESCENT-II Trial.

    Science.gov (United States)

    Lubbers, Marisa; Coenen, Adriaan; Kofflard, Marcel; Bruning, Tobias; Kietselaer, Bas; Galema, Tjebbe; Kock, Marc; Niezen, Andre; Das, Marco; van Gent, Marco; van den Bos, Ewout-Jan; van Woerkens, Leon; Musters, Paul; Kooij, Suze; Nous, Fay; Budde, Ricardo; Hunink, Miriam; Nieman, Koen

    2017-12-08

    This study sought to assess the effectiveness, efficiency, and safety of a tiered, comprehensive cardiac computed tomography (CT) protocol in comparison with functional testing. Although CT angiography accurately rules out coronary artery disease (CAD), incorporation of CT myocardial perfusion imaging as part of a tiered diagnostic approach could improve the clinical value and efficiency of cardiac CT in the diagnostic work-up of patients with angina pectoris. Between July 2013 and November 2015, 268 patients (mean age 58 years; 49% female) with stable angina (mean pre-test probability 54%) were prospectively randomized between cardiac CT and standard guideline-directed functional testing (95% exercise electrocardiography). The tiered cardiac CT protocol included a calcium scan, followed by CT angiography if calcium was detected. Patients with ≥50% stenosis on CT angiography underwent CT myocardial perfusion imaging. By 6 months, the primary endpoint, the rate of invasive coronary angiograms without a European Society of Cardiology class I indication for revascularization, was lower in the CT group than in the functional testing group (2 of 130 [1.5%] vs. 10 of 138 [7.2%]; p = 0.035), whereas the proportion of invasive angiograms with a revascularization indication was higher (88% vs. 50%; p = 0.017). The median duration until the final diagnosis was 0 (0 of 0) days in the CT group and 0 (0 of 17) in the functional testing group (p CT required further testing, compared with 37% in the functional testing group (p CT group (3.1 mSv [interquartile range: 1.6 to 7.8] vs. 0 mSv [interquartile range: 0.0 to 7.1]; p CT protocol with dynamic perfusion imaging offers a fast and efficient alternative to functional testing. (Comprehensive Cardiac CT Versus Exercise Testing in Suspected Coronary Artery Disease 2 [CRESCENT2]; NCT02291484). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  11. CT Perfusion Characteristics Identify Metastatic Sites in Liver

    Directory of Open Access Journals (Sweden)

    Yuan Wang

    2015-01-01

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

  12. CT Perfusion Characteristics Identify Metastatic Sites in Liver.

    Science.gov (United States)

    Wang, Yuan; Hobbs, Brian P; Ng, Chaan S

    2015-01-01

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

  13. CT-based Techniques for Brain Perfusion.

    Science.gov (United States)

    Krishnan, Pradeep; Murphy, Amanda; Aviv, Richard I

    2017-06-01

    Recent rapid advances in endovascular treatment for acute ischemic stroke highlight the crucial role of neuroimaging especially multimodal computed tomography (CT) including CT perfusion in stroke triage and management decisions. With an increasing focus on changes in cerebral physiology along with time-based matrices in clinical decisions for acute ischemic stroke, CT perfusion provides a rapid and practical modality for assessment and identification of salvageable tissue at risk and infarct core and provides a better understanding of the changes in cerebral physiology. Although there are challenges with the lack of standardization and accuracy of quantitative assessment, CT perfusion is evolving as a cornerstone for imaging-based strategies in the rapid management of acute ischemic stroke.

  14. Tissue-specific sparse deconvolution for brain CT perfusion.

    Science.gov (United States)

    Fang, Ruogu; Jiang, Haodi; Huang, Junzhou

    2015-12-01

    Enhancing perfusion maps in low-dose computed tomography perfusion (CTP) for cerebrovascular disease diagnosis is a challenging task, especially for low-contrast tissue categories where infarct core and ischemic penumbra usually occur. Sparse perfusion deconvolution has been recently proposed to effectively improve the image quality and diagnostic accuracy of low-dose perfusion CT by extracting the complementary information from the high-dose perfusion maps to restore the low-dose using a joint spatio-temporal model. However the low-contrast tissue classes where infarct core and ischemic penumbra are likely to occur in cerebral perfusion CT tend to be over-smoothed, leading to loss of essential biomarkers. In this paper, we propose a tissue-specific sparse deconvolution approach to preserve the subtle perfusion information in the low-contrast tissue classes. We first build tissue-specific dictionaries from segmentations of high-dose perfusion maps using online dictionary learning, and then perform deconvolution-based hemodynamic parameters estimation for block-wise tissue segments on the low-dose CTP data. Extensive validation on clinical datasets of patients with cerebrovascular disease demonstrates the superior performance of our proposed method compared to state-of-art, and potentially improve diagnostic accuracy by increasing the differentiation between normal and ischemic tissues in the brain. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. CT perfusion study of neck lymph nodes

    International Nuclear Information System (INIS)

    Zhong Jin; Liu Jun; Hua Rui; Qiao Hui; Gong Yi

    2011-01-01

    Objective: To study the CT perfusion features of various lymph nodes in the neck. Methods: Dynamic perfusion CT scanning was performed in 83 neck lymph nodes proved by pathology, including tuberculosis lymph nodes, lymphoma and metastatic lymph nodes. The shapes, blood flow modes, and perfusion parameters of these lymph nodes were compared among 3 groups. Statistical analysis of L/T and CT perfusion parameters was performed by one-way ANOVA and LSD test. Results: The values of MTT of tuberculosis lymph nodes, lymphoma and metastatic lymph nodes were (28.13±5.08), (31.08±5.82), and (11.24±5.31) s, respectively. The MTT of metastatic lymph nodes was statistically lower than that of tuberculosis lymph nodes and lymphoma (P -1 · 100 g -1 , respectively. The values of BV were (24.68±2.84), (25.30±3.16), and (25.15± 8.81) ml·100 g -1 respectively. The values of TTP were (40.90±8.85), (40.67±6.45), and (40.98±6.62) s, respectively. There were no significant differences in L/T, BF, BV and TTP among tuberculosis lymph nodes, lymphoma and metastatic lymph nodes (P>0.05). Conclusion: CT perfusion, especially combination functional imaging with perfusion images may be helpful in judging the nature of neck lymph nodes. (authors)

  16. Myocardial perfusion or multi cuts CT: When and how?

    International Nuclear Information System (INIS)

    Grossman, G.

    2015-01-01

    Multi Slice CT: in patients with intermediate probability mainly to exclude coronary artery disease (acute chest pain), Myocardial perfusion in patients with intermediate probability of coronary disease. To exclude and confirm ischemia and definition of conduct. There is no definition of superiority between strategies

  17. Multi-detector CT perfusion

    Directory of Open Access Journals (Sweden)

    Ashraf M. Enite

    2016-09-01

    Conclusion: CTP is a promising non-invasive technique assessing the efficacy, predicting early response to local treatment therapies and monitoring tumor recurrence. It assesses the degree of post therapy tumor perfusion especially the degree of arterialization.

  18. Intracranial CT angiography obtained from a cerebral CT perfusion examination

    NARCIS (Netherlands)

    Gratama van Andel, H. A. F.; Venema, H. W.; Majoie, C. B.; den Heeten, G. J.; Grimbergen, C. A.; Streekstra, G. J.

    2009-01-01

    CT perfusion (CTP) examinations of the brain are performed increasingly for the evaluation of cerebral blood flow in patients with stroke and vasospasm after subarachnoid hemorrhage. Of the same patient often also a CT angiography (CTA) examination is performed. This study investigates the

  19. Early response evaluation using CT-perfusion one day after transarterial chemoembolization for HCC predicts treatment response and long-term disease control.

    Science.gov (United States)

    Tamandl, Dietmar; Waneck, Fredrik; Sieghart, Wolfgang; Unterhumer, Sylvia; Kölblinger, Claus; Baltzer, Pascal; Ba-Ssalamah, Ahmed; Loewe, Christian

    2017-05-01

    To determine the value of CT perfusion (CTP) for early response assessment after transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). Between April 2013 and April 2015, 41 HCC (16 patients) were included in this study. CT perfusion was performed before and one day after TACE. Blood flow (BF), blood volume (BV), time to start (TTS), arterial liver perfusion (ALP), portal liver perfusion (PVP) and hepatic perfusion index (HPI) were measured. Quantitative perfusion values before and after TACE were compared to the response assessed using mRECIST criteria six weeks after TACE and long-term outcome was assessed. Twenty-one lesions (51%) had complete remission (CR) and five (12%) had partial response (PR) six weeks after TACE. CTP parameters were significantly reduced after TACE in responders (PR, CR, pCT perfusion detects lesions with complete response one day after TACE, and is a feasible tool for early response assessment. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Brain perfusion-CT in acute stroke patients

    International Nuclear Information System (INIS)

    Andreev, T.; Totsev, N.; Tzvetanov, P.

    2013-01-01

    Since 1979 when Grodfrey Hounsfield and Allan Corman introduced the computed tomography new generations of CT were developed that improved the special resolution and time of acquisition. The role of neuro-imaging in the evaluation of acute stroke has changed dramatically in the past decade. Previously, neuro-imaging was used in this set-ting to provide anatomic imaging that indicated the presence or absence of acute cerebral ischemia and excluded lesions that produce symptoms or signs mimicking those of stroke, such as hemorrhage and neoplasms. More recently, the introduction of thrombolysis has changed the goals of neuro-imaging from providing solely anatomic information to providing physiologic information that could help to determine which patients might benefit from therapy. In particular, significant emphasis has been placed on the delineation of the ischemic penumbra, also called tissue at risk. Modem CT survey, consisting of three indissociable elements; noncontrast CT (NCT) of course, perfusion-CT (PCT) and CT-angiography (CTA), fulfill all the requirements for hyperacute stroke imaging. CTA can define the occlusion site, depict arterial dissection, grade collateral blood flow, and characterize atherosclerotic disease, whereas PCT accurately defines the infarct core and the ischemic penumbra. CT offers a number of practical advantages over other cerebral perfusion imaging methods, including its wide availability. Using PCT and CTA to define new individualized strategies for acute reperfusion will allow more acute stroke patients to benefit from thrombolytic therapy. Key words: Stroke. Penumbra. Computed Tomography. Perfusion-CT. CT Angiography. Outcome

  1. Whole brain CT perfusion on a 320-slice CT scanner

    Directory of Open Access Journals (Sweden)

    Jai Jai Shiva Shankar

    2011-01-01

    Full Text Available Computed tomography perfusion (CTP has been criticized for limited brain coverage. This may result in inadequate coverage of the lesion, inadequate arterial input function, or omission of the lesion within the target perfusion volume. The availability of 320-slice CT scanners offers whole brain coverage. This minimizes the chances of misregistration of lesions regardless of location, and makes the selection of the arterial input function easy. We present different clinical scenarios in which whole brain CTP is especially useful.

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

    2017-01-01

    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

  3. C-Arm Conebeam CT Perfusion Imaging in the Angiographic Suite: A Comparison with Multidetector CT Perfusion Imaging.

    Science.gov (United States)

    Niu, K; Yang, P; Wu, Y; Struffert, T; Doerfler, A; Schafer, S; Royalty, K; Strother, C; Chen, G-H

    2016-07-01

    Perfusion imaging in the angiography suite may provide a way to reduce time from stroke onset to endovascular revascularization of patients with large-vessel occlusion. Our purpose was to compare conebeam CT perfusion with multidetector CT perfusion. Data from 7 subjects with both multidetector CT perfusion and conebeam CT perfusion were retrospectively processed and analyzed. Two algorithms were used to enhance temporal resolution and temporal sampling density and reduce the noise of conebeam CT data before generating perfusion maps. Two readers performed qualitative image-quality evaluation on maps by using a 5-point scale. ROIs indicating CBF/CBV abnormalities were drawn. Quantitative analyses were performed by using the Sørensen-Dice coefficients to quantify the similarity of abnormalities. A noninferiority hypothesis was tested to compare conebeam CT perfusion against multidetector CT perfusion. Average image-quality scores for multidetector CT perfusion and conebeam CT perfusion images were 2.4 and 2.3, respectively. The average confidence score in diagnosis was 1.4 for both multidetector CT and conebeam CT; the average confidence scores for the presence of a CBV/CBF mismatch were 1.7 (κ = 0.50) and 1.5 (κ = 0.64). For multidetector CT perfusion and conebeam CT perfusion maps, the average scores of confidence in making treatment decisions were 1.4 (κ = 0.79) and 1.3 (κ = 0.90). The area under the visual grading characteristic for the above 4 qualitative quality scores showed an average area under visual grading characteristic of 0.50, with 95% confidence level cover centered at the mean for both readers. The Sørensen-Dice coefficient for CBF maps was 0.81, and for CBV maps, 0.55. After postprocessing methods were applied to enhance image quality for conebeam CT perfusion maps, the conebeam CT perfusion maps were not inferior to those generated from multidetector CT perfusion. © 2016 by American Journal of Neuroradiology.

  4. Combined evaluation of regional coronary artery calcium and myocardial perfusion by82Rb PET/CT in the identification of obstructive coronary artery disease.

    Science.gov (United States)

    Zampella, Emilia; Acampa, Wanda; Assante, Roberta; Nappi, Carmela; Gaudieri, Valeria; Mainolfi, Ciro Gabriele; Green, Roberta; Cantoni, Valeria; Panico, Mariarosaria; Klain, Michele; Petretta, Mario; Slomka, Piotr J; Cuocolo, Alberto

    2018-01-25

    Cardiac imaging with PET/CT allows measurement of coronary artery calcium (CAC), myocardial perfusion and coronary vascular function. We investigated whether the combined assessment of regional CAC score, ischemic total perfusion deficit (ITPD) and quantitative coronary vascular function would further improve the diagnostic accuracy of PET/CT in predicting obstructive coronary artery disease (CAD). We analyzed 113 patients with suspected CAD referred to 82 Rb PET/CT myocardial perfusion imaging with available coronary angiographic data. Obstructive CAD was defined as ≥75% stenosis. The receiver operating characteristic area under curve (AUC) was applied to evaluate the ability of CAC score, ITPD, hyperemic myocardial blood flow (MBF) and coronary flow reserve (CFR) to identify CAD. Vessels with obstructive CAD (71 vessels) had higher ITPD (4.6 ± 6.2 vs. 0.6 ± 1.3) and lower hyperemic MBF (1.01 ± 0.5 vs. 1.75 ± 0.6 ml/min/g) and CFR (1.56 ± 0.6 vs. 2.38 ± 0.7; all p < 0.001) than those without. In prediction of per-vessel CAD, the AUCs for the models including CAC/ITPD/hyperemic MBF (0.869) and CAC/ITPD/CFR (0.875) were higher (both p < 0.01) than for the model including CAC/ITPD (0.790). Compared with CAC/ITPD, continuous net reclassification improvement was 0.69 (95% bootstrap confidence interval, CI, 0.365-1.088) for the CAC/ITPD/hyperemic MBF model and 0.99 (95% bootstrap CI 0.64-1.26) for the CAC/ITPD/CFR model. Hyperemic MBF and CFR provide incremental information about the presence of CAD over CAC score and perfusion imaging parameters. The combined use of CAC, myocardial perfusion imaging and quantitative coronary vascular function in may help predict more accurately the presence of obstructive CAD.

  5. Validation of CT brain perfusion methods using a realistic dynamic head phantom.

    Science.gov (United States)

    Riordan, Alan J; Prokop, Mathias; Viergever, Max A; Dankbaar, Jan Willem; Smit, Ewoud J; de Jong, Hugo W A M

    2011-06-01

    Development and evaluation of a realistic hybrid head phantom for the validation of quantitative CT brain perfusion methods. A combination, or hybrid, of CT images of an anthropomorphic head phantom together with clinically acquired MRI brain images was used to construct a dynamic hybrid head phantom. Essential CT imaging parameters such as spatially dependent noise, effects of resolution, tube settings, and reconstruction parameters were intrinsically included by scanning a skull phantom using CT perfusion (CTP) protocols with varying mAs. These data were combined with processed high resolution 7T clinical MRI images to include healthy and diseased brain parenchyma, as well as the cerebral vascular system. Time attenuation curves emulating contrast bolus passage based on perfusion as observed in clinical studies were added. Using the phantom, CTP images were generated using three brain perfusion calculation methods: bcSVD, sSVD, and fit-based deconvolution, and the linearity and accuracy of the three calculation methods was assessed. Dependency of perfusion outcome on calculation method was compared to clinical data. Furthermore, the potential of the phantom to optimize brain perfusion packages was investigated. All perfusion calculation methods showed overestimation of low perfusion values and underestimation of high perfusion values. Good correlation in behavior between phantom and clinical data was found (R2 = 0.84). A dynamic hybrid head phantom constructed from CT and MRI data was demonstrated to realistically represent clinical CTP studies, which is useful for assessing CT brain perfusion acquisition, reconstruction, and analysis.

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

    Science.gov (United States)

    Djuric-Stefanovic, A; Saranovic, Dj; Sobic-Saranovic, D; Masulovic, D; Artiko, V

    2015-03-01

    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. 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 (rS). 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, pCT perfusion measurements and statistically significant correlation was proved. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Whole-brain dynamic CT angiography and perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Orrison, W.W. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Department of Medical Education, University of Nevada School of Medicine, Reno, NV (United States); Snyder, K.V.; Hopkins, L.N. [Department of Neurosurgery, Millard Fillmore Gates Circle Hospital, Buffalo, NY (United States); Roach, C.J. [School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Ringdahl, E.N. [Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV (United States); Nazir, R. [Shifa International Hospital, Islamabad (Pakistan); Hanson, E.H., E-mail: eric.hanson@amigenics.co [College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States)

    2011-06-15

    The availability of whole brain computed tomography (CT) perfusion has expanded the opportunities for analysing the haemodynamic parameters associated with varied neurological conditions. Examples demonstrating the clinical utility of whole-brain CT perfusion imaging in selected acute and chronic ischaemic arterial neurovascular conditions are presented. Whole-brain CT perfusion enables the detection and focused haemodynamic analyses of acute and chronic arterial conditions in the central nervous system without the limitation of partial anatomical coverage of the brain.

  8. Prior CT May Improve Diagnostic Confidence in Myocardial Perfusion Imaging.

    Science.gov (United States)

    Mehta, Pareen; Wassef, Heidi; Colletti, Patrick M

    2015-10-01

    Many patients with matching myocardial perfusion imaging defects may have prior CT examinations that include the myocardial region of interest, such as a CT chest or CT abdomen. We correlate these perfusion defects with available prior CT examinations to determine if this will improve diagnostic confidence. Myocardial perfusion scans were reviewed to identify cases with myocardial perfusion defects and prior CT imaging that included the myocardium. The CT was reviewed for evidence of myocardial injury that correlated with the perfusion defect. A retrospective review of 732 myocardial perfusion scans was performed, of which 69 cases with perfusion defects were identified that also had prior CT imaging available for review. Of this subset of patients, 19 patients had findings on the CT scan compatible with ischemia or infarction in the expected region of the perfusion defect, which allowed for a more confident diagnosis. Reviewing a prior CT scan, if available, during the interpretation of a myocardial perfusion scan, can help improve diagnostic confidence in over 25% of cases. This can lead to decreased indeterminate results and can be used to potentially avoid unhelpful further testing.

  9. The dream of a one-stop-shop : Meta-analysis on myocardial perfusion CT

    NARCIS (Netherlands)

    Pelgrim, Gert Jan; Dorrius, Monique; Xie, Xueqian; den Dekker, Martijn A. M.; Schoepf, U. Joseph; Henzler, Thomas; Oudkerk, Matthijs; Vliegenthart, Rozemarijn

    2015-01-01

    Purpose: To determine the diagnostic performance of computed tomography (CT) perfusion techniques for the detection of functionally relevant coronary artery disease (CAD) in comparison to reference standards, including invasive coronary angiography (ICA), single photon emission computed tomography

  10. Perfusion measurements by micro-CT using prior image constrained compressed sensing (PICCS): initial phantom results.

    Science.gov (United States)

    Nett, Brian E; Brauweiler, Robert; Kalender, Willi; Rowley, Howard; Chen, Guang-Hong

    2010-04-21

    Micro-CT scanning has become an accepted standard for anatomical imaging in small animal disease and genome mutation models. Concurrently, perfusion imaging via tracking contrast dynamics after injection of an iodinated contrast agent is a well-established tool for clinical CT scanners. However, perfusion imaging is not yet commercially available on the micro-CT platform due to limitations in both radiation dose and temporal resolution. Recent hardware developments in micro-CT scanners enable continuous imaging of a given volume through the use of a slip-ring gantry. Now that dynamic CT imaging is feasible, data may be acquired to measure tissue perfusion using a micro-CT scanner (CT Imaging, Erlangen, Germany). However, rapid imaging using micro-CT scanners leads to high image noise in individual time frames. Using the standard filtered backprojection (FBP) image reconstruction, images are prohibitively noisy for calculation of voxel-by-voxel perfusion maps. In this study, we apply prior image constrained compressed sensing (PICCS) to reconstruct images with significantly lower noise variance. In perfusion phantom experiments performed on a micro-CT scanner, the PICCS reconstruction enabled a reduction to 1/16 of the noise variance of standard FBP reconstruction, without compromising the spatial or temporal resolution. This enables a significant increase in dose efficiency, and thus, significantly less exposure time is needed to acquire images amenable to perfusion processing. This reduction in required irradiation time enables voxel-by-voxel perfusion maps to be generated on micro-CT scanners. Sample perfusion maps using a deconvolution-based perfusion analysis are included to demonstrate the improvement in image quality using the PICCS algorithm.

  11. Perfusion measurements by micro-CT using prior image constrained compressed sensing (PICCS): initial phantom results

    International Nuclear Information System (INIS)

    Nett, Brian E; Chen, G-H; Brauweiler, Robert; Kalender, Willi; Rowley, Howard

    2010-01-01

    Micro-CT scanning has become an accepted standard for anatomical imaging in small animal disease and genome mutation models. Concurrently, perfusion imaging via tracking contrast dynamics after injection of an iodinated contrast agent is a well-established tool for clinical CT scanners. However, perfusion imaging is not yet commercially available on the micro-CT platform due to limitations in both radiation dose and temporal resolution. Recent hardware developments in micro-CT scanners enable continuous imaging of a given volume through the use of a slip-ring gantry. Now that dynamic CT imaging is feasible, data may be acquired to measure tissue perfusion using a micro-CT scanner (CT Imaging, Erlangen, Germany). However, rapid imaging using micro-CT scanners leads to high image noise in individual time frames. Using the standard filtered backprojection (FBP) image reconstruction, images are prohibitively noisy for calculation of voxel-by-voxel perfusion maps. In this study, we apply prior image constrained compressed sensing (PICCS) to reconstruct images with significantly lower noise variance. In perfusion phantom experiments performed on a micro-CT scanner, the PICCS reconstruction enabled a reduction to 1/16 of the noise variance of standard FBP reconstruction, without compromising the spatial or temporal resolution. This enables a significant increase in dose efficiency, and thus, significantly less exposure time is needed to acquire images amenable to perfusion processing. This reduction in required irradiation time enables voxel-by-voxel perfusion maps to be generated on micro-CT scanners. Sample perfusion maps using a deconvolution-based perfusion analysis are included to demonstrate the improvement in image quality using the PICCS algorithm.

  12. Diagnostic Performance of Dual-Energy CT Stress Myocardial Perfusion Imaging: Direct Comparison With Cardiovascular MRI

    Science.gov (United States)

    Ko, Sung Min; Song, Meong Gun; Chee, Hyun Kun; Hwang, Hweung Kon; Feuchtner, Gudrun Maria; Min, James K.

    2014-01-01

    OBJECTIVE The purpose of this study was to assess the diagnostic performance of stress perfusion dual-energy CT (DECT) and its incremental value when used with coronary CT angiography (CTA) for identifying hemodynamically significant coronary artery disease. SUBJECTS AND METHODS One hundred patients with suspected or known coronary artery disease without chronic myocardial infarction detected with coronary CTA underwent stress perfusion DECT, stress cardiovascular perfusion MRI, and invasive coronary angiography (ICA). Stress perfusion DECT and cardiovascular stress perfusion MR images were used for detecting perfusion defects. Coronary CTA and ICA were evaluated in the detection of ≥ 50% coronary stenosis. The diagnostic performance of coronary CTA for detecting hemodynamically significant stenosis was assessed before and after stress perfusion DECT on a pervessel basis with ICA and cardiovascular stress perfusion MRI as the reference standard. RESULTS The performance of stress perfusion DECT compared with cardiovascular stress perfusion MRI on a per-vessel basis in the detection of perfusion defects was sensitivity, 89%; specificity, 74%; positive predictive value, 73%; negative predictive value, 90%. Per segment, these values were sensitivity, 76%; specificity, 80%; positive predictive value, 63%; and negative predictive value, 88%. Compared with ICA and cardiovascular stress perfusion MRI per vessel territory the sensitivity, specificity, positive predictive value, and negative predictive value of coronary CTA were 95%, 61%, 61%, and 95%. The values for stress perfusion DECT were 92%, 72%, 68%, and 94%. The values for coronary CTA and stress perfusion DECT were 88%, 79%, 73%, and 91%. The ROC AUC increased from 0.78 to 0.84 (p = 0.02) with the use of coronary CTA and stress perfusion DECT compared with coronary CTA alone. CONCLUSION Stress perfusion DECT plays a complementary role in enhancing the accuracy of coronary CTA for identifying hemodynamically

  13. Dynamic CT perfusion measurement in a cardiac phantom.

    Science.gov (United States)

    Ziemer, Benjamin P; Hubbard, Logan; Lipinski, Jerry; Molloi, Sabee

    2015-10-01

    Widespread clinical implementation of dynamic CT myocardial perfusion has been hampered by its limited accuracy and high radiation dose. The purpose of this study was to evaluate the accuracy and radiation dose reduction of a dynamic CT myocardial perfusion technique based on first pass analysis (FPA). To test the FPA technique, a pulsatile pump was used to generate known perfusion rates in a range of 0.96-2.49 mL/min/g. All the known perfusion rates were determined using an ultrasonic flow probe and the known mass of the perfusion volume. FPA and maximum slope model (MSM) perfusion rates were measured using volume scans acquired from a 320-slice CT scanner, and then compared to the known perfusion rates. The measured perfusion using FPA (P(FPA)), with two volume scans, and the maximum slope model (P(MSM)) were related to known perfusion (P(K)) by P(FPA) = 0.91P(K) + 0.06 (r = 0.98) and P(MSM) = 0.25P(K) - 0.02 (r = 0.96), respectively. The standard error of estimate for the FPA technique, using two volume scans, and the MSM was 0.14 and 0.30 mL/min/g, respectively. The estimated radiation dose required for the FPA technique with two volume scans and the MSM was 2.6 and 11.7-17.5 mSv, respectively. Therefore, the FPA technique can yield accurate perfusion measurements using as few as two volume scans, corresponding to approximately a factor of four reductions in radiation dose as compared with the currently available MSM. In conclusion, the results of the study indicate that the FPA technique can make accurate dynamic CT perfusion measurements over a range of clinically relevant perfusion rates, while substantially reducing radiation dose, as compared to currently available dynamic CT perfusion techniques.

  14. Application of CT perfusion imaging in radiotherapy for lung cancer

    International Nuclear Information System (INIS)

    Xia Guangrong; Liu Guimei; He Wen; Jin Guohua; Xie Ruming; Xu Yongxiang; Li Xiaobo; Li Xuebing

    2011-01-01

    .9 s, significantly longer than that of the NSCLC patients (6.5 s, t=2.54, P<0.05). The MTT of the tumor with the area ≤ 10 cm 2 was 11.2 s, significantly longer than that of the tumors with an area > 10 cm 2 (5.8 s, t=2.59, P<0.05). The BV of the responder group was 19.2 ml· 100 g -1 , significantly higher than that of the non-responder group (4.6 ml· 100 g -1 , t=3.62, P<0.05). There were not significant differences in all the perfusion characteristics between the cases with the disease-free advanced survival time ≤ 10 months and those with disease-free advanced survival time > 10 months. Conclusions: CT perfusion imaging helps in diagnosis and radiotherapy of lung cancer to a certain degree. (authors)

  15. CT Perfusion of the Liver: Principles and Applications in Oncology

    Science.gov (United States)

    Kim, Se Hyung; Kamaya, Aya

    2014-01-01

    With the introduction of molecularly targeted chemotherapeutics, there is an increasing need for defining new response criteria for therapeutic success because use of morphologic imaging alone may not fully assess tumor response. Computed tomographic (CT) perfusion imaging of the liver provides functional information about the microcirculation of normal parenchyma and focal liver lesions and is a promising technique for assessing the efficacy of various anticancer treatments. CT perfusion also shows promising results for diagnosing primary or metastatic tumors, for predicting early response to anticancer treatments, and for monitoring tumor recurrence after therapy. Many of the limitations of early CT perfusion studies performed in the liver, such as limited coverage, motion artifacts, and high radiation dose of CT, are being addressed by recent technical advances. These include a wide area detector with or without volumetric spiral or shuttle modes, motion correction algorithms, and new CT reconstruction technologies such as iterative algorithms. Although several issues related to perfusion imaging—such as paucity of large multicenter trials, limited accessibility of perfusion software, and lack of standardization in methods—remain unsolved, CT perfusion has now reached technical maturity, allowing for its use in assessing tumor vascularity in larger-scale prospective clinical trials. In this review, basic principles, current acquisition protocols, and pharmacokinetic models used for CT perfusion imaging of the liver are described. Various oncologic applications of CT perfusion of the liver are discussed and current challenges, as well as possible solutions, for CT perfusion are presented. © RSNA, 2014 Online supplemental material is available for this article. PMID:25058132

  16. Diagnostic accuracy of static CT perfusion for the detection of myocardial ischemia

    DEFF Research Database (Denmark)

    Sørgaard, Mathias Holm; Kofoed, Klaus Fuglsang; Linde, Jesper James

    2016-01-01

    OBJECTIVES: The aim of this study is to provide a meta-analysis of all published studies assessing the diagnostic accuracy of stress CT myocardial perfusion imaging (CTP) in patients suspected of or with known coronary artery disease. This analysis is limited to static stress CTP. METHODS......: Systematic literature review and meta-analysis of studies examining the diagnostic accuracy of static CTP imaging alone or combined with coronary CT angiography (CTA) in comparison to single photon emission computed tomography (SPECT), magnetic resonance perfusion (MRP), and/or invasive coronary angiography......). CONCLUSION: In selected patients, static CT myocardial perfusion has high diagnostic accuracy to detecting myocardial ischemia. Specificity increases significantly when CT myocardial perfusion is combined with coronary CTA....

  17. Low dose CT perfusion using k-means clustering

    Science.gov (United States)

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

    2016-03-01

    We aim at improving low dose CT perfusion functional parameters maps and CT images quality, preserving quantitative information. In a dynamic CT perfusion dataset, each voxel is measured T times, where T is the number of acquired time points. In this sense, we can think about a voxel as a point in a T-dimensional space, where the coordinates of the voxels would be the values of its time attenuation curve (TAC). Starting from this idea, a k-means algorithm was designed to group voxels in K classes. A modified guided time-intensity profile similarity (gTIPS) filter was implemented and applied only for those voxels belonging to the same class. The approach was tested on a digital brain perfusion phantom as well as on clinical brain and body perfusion datasets, and compared to the original TIPS implementation. The TIPS filter showed the highest CNR improvement, but lowest spatial resolution. gTIPS proved to have the best combination of spatial resolution and CNR improvement for CT images, while k-gTIPS was superior to both gTIPS and TIPS in terms of perfusion maps image quality. We demonstrate k-means clustering analysis can be applied to denoise dynamic CT perfusion data and to improve functional maps. Beside the promising results, this approach has the major benefit of being independent from the perfusion model employed for functional parameters calculation. No similar approaches were found in literature.

  18. Dynamic CT myocardial perfusion imaging identifies early perfusion abnormalities in diabetes and hypertension : Insights from a multicenter registry

    NARCIS (Netherlands)

    Vliegenthart, Rozemarijn; De Cecco, Carlo N.; Wichmann, Julian L.; Meinel, Felix G.; Pelgrim, Gert Jan; Tesche, Christian; Ebersberger, Ullrich; Pugliese, Francesca; Bamberg, Fabian; Choe, Yeon Hyeon; Wang, Yining; Schoepf, U. Joseph

    2016-01-01

    Background: To identify patients with early signs of myocardial perfusion reduction, a reference base for perfusion measures is needed. Objective: To analyze perfusion parameters derived from dynamic computed tomography perfusion imaging (CTPI) in patients with suspected coronary artery disease

  19. Effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies.

    Science.gov (United States)

    Murase, Kenya; Nanjo, Takafumi; Ii, Satoshi; Miyazaki, Shohei; Hirata, Masaaki; Sugawara, Yoshifumi; Kudo, Masayuki; Sasaki, Kousuke; Mochizuki, Teruhito

    2005-11-07

    The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation x 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current.

  20. Effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies

    International Nuclear Information System (INIS)

    Murase, Kenya; Nanjo, Takafumi; Ii, Satoshi; Miyazaki, Shohei; Hirata, Masaaki; Sugawara, Yoshifumi; Kudo, Masayuki; Sasaki, Kousuke; Mochizuki, Teruhito

    2005-01-01

    The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation x 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current

  1. A direct comparison of the sensitivity of CT and MR cardiac perfusion using a myocardial perfusion phantom.

    OpenAIRE

    Otton, James; Morton, Geraint; Schuster, Andreas; Bigalke, Boris; Marano, Riccardo; Olivotti, Luca; Nagel, Eike; Chiribiri, Amedeo

    2013-01-01

    BACKGROUND: Direct comparison of CT and magnetic resonance (MR) perfusion techniques has been limited and in vivo assessment is affected by physiological variability, timing of image acquisition, and parameter selection. OBJECTIVE: We precisely compared high-resolution k-t SENSE MR cardiac perfusion at 3 T with single-phase CT perfusion (CTP) under identical imaging conditions. METHODS: We used a customized MR imaging and CT compatible dynamic myocardial perfusion phantom to represe...

  2. Development of an Ex Vivo, Beating Heart Model for CT Myocardial Perfusion

    NARCIS (Netherlands)

    Pelgrim, Gert Jan; Das, Marco; Haberland, Ulrike; Slump, Cees; Handayani, Astri; van Tuijl, Sjoerd; Stijnen, Marco; Klotz, Ernst; Oudkerk, Matthijs; Wildberger, Joachim E.; Vliegenthart, Rozemarijn

    2015-01-01

    Objective. To test the feasibility of a CT-compatible, ex vivo, perfused porcine heart model for myocardial perfusion CT imaging. Methods. One porcine heart was perfused according to Langendorff. Dynamic perfusion scanning was performed with a second-generation dual source CT scanner. Circulatory

  3. 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

  4. Diagnostic performance of on-site CT-derived fractional flow reserve versus CT perfusion.

    Science.gov (United States)

    Yang, Dong Hyun; Kim, Young-Hak; Roh, Jae Hyung; Kang, Joon-Won; Ahn, Jung-Min; Kweon, Jihoon; Lee, Jung Bok; Choi, Seong Hoon; Shin, Eun-Seok; Park, Duk-Woo; Kang, Soo-Jin; Lee, Seung-Whan; Lee, Cheol Whan; Park, Seong-Wook; Park, Seung-Jung; Lim, Tae-Hwan

    2017-04-01

    To compare the diagnostic accuracy of on-site computed tomography (CT)-derived fractional flow reserve (FFR) and stress CT myocardial perfusion (CTP) in patients with coronary artery disease. Using a prospective CTP registry, 72 patients with invasive FFR were enrolled. CT-derived FFR was computed on-site using rest-phase CTP data. The diagnostic accuracies of coronary CT angiography (CCTA), CT-derived FFR, and stress CTP were evaluated using an area under the receiver-operating characteristic curve (AUC) with invasive FFR as a reference standard. Logistic regression and the net reclassification index (NRI) were used to evaluate incremental differences in CT-derived FFR or CTP compared with CCTA alone. The per-vessel prevalence of haemodynamically significant stenosis (FFR ≤ 0.80) was 39% (54/138). Per-vessel sensitivity and specificity were 94 and 66% for CCTA, 87 and 77% for CT-derived FFR, and 79 and 91% for CTP, respectively. There was no significant difference in the AUC values of CT-derived FFR and CTP (P = 0.845). The diagnostic performance of CCTA (AUC = 0.856) was improved by combining it with CT-derived FFR (AUC = 0.919, P = 0.004, NRI = 1.01) or CTP (AUC = 0.913, P = 0.004, NRI = 0.66). CT-derived FFR values had a moderate correlation with invasive FFR (r = 0.671, P CT-derived FFR combined with CCTA provides an incremental diagnostic improvement over CCTA alone in identifying haemodynamically significant stenosis defined by invasive FFR, with a diagnostic accuracy comparable with CTP. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  5. Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

    Energy Technology Data Exchange (ETDEWEB)

    Tutcu, Semra [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Serter, Selim, E-mail: serterselim@gmail.co [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Kaya, Yavuz; Kara, Eray [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Nese, Nalan [Department of Pathology, Celal Bayar University, School of Medicine, Manisa (Turkey); Pekindil, Goekhan [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Coskun, Teoman [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey)

    2010-08-15

    Purpose: It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT. Materials and methods: Forty Sprague-Dawley rats of both genders with average weights of 250 g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses. Results: In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p < 0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance. Conclusion: The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.

  6. Volume/perfusion ratio from lung SPECT/CT.

    Science.gov (United States)

    Schaefer, Wolfgang Michael; Knollmann, Daniela; Avondo, Jerome; Meyer, Andreas

    2018-02-01

    In pulmonary emphysema lung volume reduction procedures (LVRP) can optimize respiratory pump function. Identification of the most affected lobe can be reached using relative lobar volume (relVol) from CT, but this approach disregards the corresponding lobar perfusion. The aim of the study was therefore to establish a new parameter combining relVol from CT and relative perfusion (relPerf) from perfusion SPECT as a single parameter (volume/perfusion ratio (VPR)) to optimize the identification procedure. As a proof of principle VPR was calculated from hybrid V-/P-SPECT/CT scans from 20 patients with severe pulmonary emphysema (SPE) before LVRP. Lung V-/P-SPECT/CT (Siemens SymbiaT) was done with Technegas and 99mTc-MAA. Quantification of lobar perfusion from scintigraphy and volume from CT was performed using "HERMES Hybrid 3D - Lung Lobe Quantification". Using normal ranges - from 12 patients with suspected pulmonary embolism and normal lung structure and perfusion - all lobes were classified as normal or abnormal to identify targets for LVRP. Normal values for VPR: right upper lobe 1.09 ± 0.10, middle lobe 1.31 ± 0.31, right lower lobe 0.87 ± 0.08; left upper lobe 1.09 ± 0.11, left lower lobe 0.87 ± 0.12. In the 20 SPE patients there were only 7 lobes with pathological values for rel- Vol, 14 lobes with pathological values for rel- Perf but 31 lobes with pathological VPR. Estimation of VPR from lung SPECT/CT enables a combined view of lobar volume and perfusion with one parameter. In SPE patients VPR allows identifying possible target structures with much higher sensitivity than when using relPerf or relVol alone. The specificity and the prognostic value of this new parameter have to be tested in a clinical trial. Schattauer GmbH.

  7. Intracranial CT angiography obtained from a cerebral CT perfusion examination

    International Nuclear Information System (INIS)

    Gratama van Andel, H. A. F.; Venema, H. W.; Majoie, C. B.; Den Heeten, G. J.; Grimbergen, C. A.; Streekstra, G. J.

    2009-01-01

    CT perfusion (CTP) examinations of the brain are performed increasingly for the evaluation of cerebral blood flow in patients with stroke and vasospasm after subarachnoid hemorrhage. Of the same patient often also a CT angiography (CTA) examination is performed. This study investigates the possibility to obtain CTA images from the CTP examination, thereby possibly obviating the CTA examination. This would save the patient exposure to radiation, contrast, and time. Each CTP frame is a CTA image with a varying amount of contrast enhancement and with high noise. To improve the contrast-to-noise ratio (CNR) we combined all 3D images into one 3D image after registration to correct for patient motion between time frames. Image combination consists of weighted averaging in which the weighting factor of each frame is proportional to the arterial contrast. It can be shown that the arterial CNR is maximized in this procedure. An additional advantage of the use of the time series of CTP images is that automatic differentiation between arteries and veins is possible. This feature was used to mask veins in the resulting 3D images to enhance visibility of arteries in maximum intensity projection (MIP) images. With a Philips Brilliance 64 CT scanner (64x0.625 mm) CTP examinations of eight patients were performed on 80 mm of brain using the toggling table technique. The CTP examination consisted of a time series of 15 3D images (2x64x0.625 mm; 80 kV; 150 mAs each) with an interval of 4 s. The authors measured the CNR in images obtained with weighted averaging, images obtained with plain averaging, and images with maximal arterial enhancement. The authors also compared CNR and quality of the images with that of regular CTA examinations and examined the effectiveness of automatic vein masking in MIP images. The CNR of the weighted averaged images is, on the average, 1.73 times the CNR of an image at maximal arterial enhancement in the CTP series, where the use of plain averaging

  8. 3D fusion of coronary CT angiography and CT myocardial perfusion imaging: Intuitive assessment of morphology and function.

    Science.gov (United States)

    von Spiczak, Jochen; Manka, Robert; Mannil, Manoj; Oebel, Sabrina; Hamada, Sandra; Higashigaito, Kai; Klotz, Ernst; Ruschitzka, Frank; Alkadhi, Hatem

    2017-11-01

    The objective of this work was to support three-dimensional fusion of coronary CT angiography (coronary CTA) and CT myocardial perfusion (CT-Perf) data visualizing coronary artery stenoses and corresponding stress-induced myocardial perfusion deficits for diagnostics of coronary artery disease. Twelve patients undergoing coronary CTA/CT-Perf after heart transplantation were included (56 ± 12 years, all males). CT image quality was rated. Coronary diameter stenoses >50% were documented for coronary CTA. Stress-induced perfusion deficits were noted for CT-Perf. A software was implemented facilitating 3D fusion imaging of coronary CTA/CT-Perf data. Coronary arteries and heart contours were segmented automatically. To overcome anatomical mismatch of coronary CTA/CT-Perf image acquisition, perfusion values were projected on the left ventricle as visualized in coronary CTA. Three resulting datasets (coronary tree/heart contour/perfusion values) were fused for combined three-dimensional rendering. 3D fusion was compared with conventional analysis of coronary CTA/CT-Perf data and to results from catheter coronary angiography. CT image quality was rated good-excellent (3.5 ± 0.5, scale 1-4). 3D fusion imaging of coronary CTA/CT-Perf data was feasible in 11/12 patients (92%). One patient (8%) was excluded from further analysis due to severe motion artifacts. 2 of 11 remaining patients (18%) showed both stress-induced perfusion deficits and relevant coronary stenoses. Using 3D fusion imaging, the ischemic region could be correlated to a culprit coronary lesion in one case (1/2 = 50%) and diagnostic findings could be rectified in the other case (1/2 = 50%). Coronary CTA was in full correspondence with catheter coronary angiography. A method for 3D fusion of coronary CTA/CT-Perf is introduced correlating relevant coronary lesions and corresponding stress-induced myocardial perfusion deficits. Copyright © 2017 Society of Cardiovascular Computed Tomography. Published

  9. CT perfusion image processing: analysis of liver tumors

    OpenAIRE

    D’Antò, Michela

    2013-01-01

    Perfusion CT imaging of the liver has potential to improve evaluation of tumour angiogenesis. Quantitative parameters can be obtained applying mathematical models to Time Attenuation Curve (TAC). However, there are still some difficulties for an accurate quantification of perfusion parameters due, for example, to algorithms employed, to mathematical model, to patient’s weight and cardiac output and to the acquisition system. In this thesis, new parameters and alternative methodologies ab...

  10. CT perfusion technique for assessment of early kidney allograft dysfunction: preliminary results.

    Science.gov (United States)

    Helck, A; Wessely, M; Notohamiprodjo, M; Schönermarck, U; Klotz, E; Fischereder, M; Schön, F; Nikolaou, K; Clevert, D A; Reiser, M; Becker, C

    2013-09-01

    To assess the benefit of quantitative computed tomography (CT) perfusion for differentiating acute tubular necrosis (ATN) and acute rejection (AR) in kidney allografts. Twenty-two patients with acute kidney allograft dysfunction caused by either AR (n = 6) or ATN (n = 16) were retrospectively included in the study. All patients initially underwent a multiphase CT angiography (CTA) protocol (12 phases, one phase every 3.5 s) covering the whole graft to exclude acute postoperative complications. Multiphase CT dataset and dedicated software were used to calculate renal blood flow. Renal biopsy or clinical course of disease served as the standard of reference. Mean effective radiation dose and mean amount of contrast media were calculated. Renal blood flow values were significantly lower (P = 0.001) in allografts undergoing AR (48.3 ± 21 ml/100 ml/min) compared with those with ATN (77.5 ± 21 ml/100 ml/min). No significant difference (P = 0.71) was observed regarding creatinine level with 5.65 ± 3.1 mg/dl in AR and 5.3 ± 1.9 mg/dl in ATN. The mean effective radiation dose of the CT perfusion protocol was 13.6 ± 5.2 mSv; the mean amount of contrast media applied was 34.5 ± 5.1 ml. All examinations were performed without complications. CT perfusion of kidney allografts may help to differentiate between ATN and rejection. • Quantitative CT perfusion of renal transplants is feasible. • CT perfusion could help to non-invasively differentiate AR from ATN. • CT perfusion might make some renal biopsies unnecessary.

  11. Differentiation between diverticulitis and colorectal cancer: quantitative CT perfusion measurements versus morphologic criteria--initial experience.

    Science.gov (United States)

    Goh, Vicky; Halligan, Steve; Taylor, Stuart A; Burling, David; Bassett, Paul; Bartram, Clive I

    2007-02-01

    To determine whether computed tomographic (CT) perfusion measurements in prospectively recruited patients can be used to differentiate between diverticulitis and colorectal cancer and to compare this discrimination with that of standard morphologic criteria. After institutional review board approval and written informed consent were obtained, 60 patients (24 men, 36 women; mean age, 69 years; range, 33.5-90.4 years; 20 patients with cancer, 20 with diverticulitis, and 20 with inactive diverticular disease) underwent CT perfusion imaging at the level of the colonic abnormality, and perfusion parameters were calculated. Analysis of variance was used to investigate any differences in perfusion between the patient groups. Two independent observers also analyzed an abdominopelvic CT study obtained immediately after the CT perfusion study and noted standard morphologic criteria for differential diagnosis. The sensitivity and specificity of CT perfusion measurements for determining the diagnostic category were compared with morphologic criteria by means of multivariate analysis to identify the most discriminatory criteria. Mean blood volume, blood flow, transit time, and permeability were significantly different between patients with cancer and those with diverticulitis (P diagnostic category were blood volume, transit time, permeability, and presence of pericolonic nodes (P = .05, .02, .04, and .02, respectively). Blood volume and blood flow each had a sensitivity of 80% and had specificity of 70% and 75%, respectively, for cancer in comparison with standard morphologic criteria: less than 5 cm of bowel involvement (45% sensitivity, 95% specificity), presence of a mass (85% sensitivity, 90% specificity), pericolonic inflammation (75% sensitivity, 5% specificity), and pericolonic nodes (90% sensitivity, 45% specificity). CT perfusion measurements enable differentiation and better discrimination, in comparison with morphologic criteria, between cancer and diverticulitis

  12. Perfusion CT in childhood stroke—Initial observations and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Zebedin, D., E-mail: doris.zebedin@medunigraz.at [Division of Pediatric Radiology, Department of Radiology, University Hospital LKH Graz (Austria); Sorantin, E.; Riccabona, M. [Division of Pediatric Radiology, Department of Radiology, University Hospital LKH Graz (Austria)

    2013-07-15

    Introduction: To report the preliminary results of contrast-enhanced perfusion multi-detector CT for diagnoses of perfusion disturbances in children with clinical suspicion of stroke. Patients and methods: Within the last two years emergency perfusion CT was performed in ten children (age: 8–17 years, male:female = 3:7) for assessment of suspected childhood stroke. These intracranial perfusion CT, intracranial CT-digital subtraction angiography (CT-DSA) and extracranial CT-angiography (CTA) studies were retrospectively reviewed and compared with MRI, follow-up CT, catheter angiography and final clinical diagnosis. The total dose length product (DLP) for the entire examination was recorded. The image quality of perfusion CT-maps, CT-DSA and CTA were evaluated with a subjective three-point scale ranging from very good to non-diagnostic image quality rating perfusion disturbance, intracranial peripheral vessel depiction, and motion- or streak artifacts. Results: In nine of ten children perfusion CT showed no false positive or false negative results. In one of ten children suffering from migraine focal hypo-perfusion was read as perfusion impairment potentially indicating early stroke, but MRI and MRA follow-up were negative. Overall, perfusion-CT with CT-DSA was rated very good in 80% of cases for the detection of perfusion disturbances and vessel anatomy. Conclusions: In comparison to standard CT, contrast-enhanced perfusion CT improves CTs’ diagnostic capability in the emergency examination of children with a strong suspicion of ischemic cerebral infarction.

  13. The diagnosis of renal perfusion abnormalities by sequential CT

    International Nuclear Information System (INIS)

    Treugut, H.; Andersson, I.; Hildell, J.; Nyman, U.; Weibull, H.

    1981-01-01

    Abnormalities of renal perfusion can be recognised more readily by sequential CT than by plain CT scan or after static enhancement with contrast medium. Haemodynamically significant stenoses of the renal arteries and total, or partial, infarcts can be diagnosed in this way. Intrarenal and capsular collaterals can be recognised by slow contrast accumulation in the infarcted area, or by the development of contrast in the sub-capsular portion of the cortex. Renal cortical necrosis is very well demonstrated by the absence of cortical perfusion; this is seen, for instance, in the DIC syndrome or during rejection after renal transplant. (orig.) [de

  14. Pancreatic Perfusion CT in Early Stage of Severe Acute Pancreatitis

    Directory of Open Access Journals (Sweden)

    Yoshihisa Tsuji

    2012-01-01

    Full Text Available Early intensive care for severe acute pancreatitis is essential for improving SAP mortality rates. However, intensive therapies for SAP are often delayed because there is no ideal way to accurately evaluate severity in the early stages. Currently, perfusion CT has been shown useful to predict prognosis of SAP in the early stage. In this presented paper, we would like to review the clinical usefulness and limitations of perfusion CT for evaluation of local and systemic complications in early stage of SAP.

  15. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    A. Mendrik (Adrienne); E.J.P.A. Vonken; B.T.J. van Ginneken (Berbke); J.R. Riordan (John ); H.W.A.M. de Jong (Hugo); T. van Seeters (Tom); E.J. Smit (Ewoud); M.A. Viergever (Max); M. Prokop (Mathias)

    2011-01-01

    textabstractCerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of

  16. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    Mendrik, A.M.; Vonken, E.J.; Ginneken, B. van; Jong, H.W. de; Riordan, A.; Seeters, T. van; Smit, E.J.; Viergever, M.A.; Prokop, M.

    2011-01-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray

  17. Complications of hemorrhagic and ischemic stroke : a CT perfusion evaluation

    NARCIS (Netherlands)

    Dankbaar, J.W.

    2010-01-01

    In this thesis the use of CT-perfusion (CTP) imaging in the evaluation of the most severe complications of subarachnoid hemorrhage (SAH)) and ischemic stroke was explored. These complications are delayed cerebral ischemia (DCI) after SAH and damage to the blood-brain barrier (BBB) after ischemic

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

    Science.gov (United States)

    Coenen, Adriaan; Lubbers, Marisa M; Kurata, Akira; Kono, Atsushi; Dedic, Admir; Chelu, Raluca G; Dijkshoorn, Marcel L; Rossi, Alexia; van Geuns, Robert-Jan M; Nieman, Koen

    2017-06-01

    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. • The transmural perfusion ratio from dynamic CT-MPI predicts functional obstructive coronary artery disease • Performance of the transmural perfusion ratio is inferior to quantified myocardial blood flow • The incremental value of the transmural perfusion ratio is limited.

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

    Science.gov (United States)

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

    2017-11-22

    To determine the degree of relationship between iodine concentrations derived from dual-energy CT (DECT) and perfusion CT parameters in patients with advanced HCC under treatment. In this single-centre IRB approved study, 16 patients with advanced HCC treated with sorafenib or radioembolization who underwent concurrent dynamic perfusion CT and multiphase DECT using a single source, fast kV switching DECT scanner were included. Written informed consent was obtained for all patients. HCC late-arterial and portal iodine concentrations, blood flow (BF)-related and blood volume (BV)-related perfusion parameters maps were calculated. Mixed-effects models of the relationship between iodine concentrations and perfusion parameters were computed. An adjusted p value (Bonferroni method) perfusion index (F=28.24, pperfusion changes. • Late-arterial iodine concentration is highly related to arterial BF and BV. • Portal iodine concentration mainly reflects tumour blood volume. • Dual-energy CT offers significantly decreased radiation dose compared with perfusion CT.

  20. Perfusion- and pattern-based quantitative CT indexes using contrast-enhanced dual-energy computed tomography in diffuse interstitial lung disease: relationships with physiologic impairment and prediction of prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Jung Won [Sungkyunkwan University School of Medicine, Department of Radiology, Kangbuk Samsung Hospital, Seoul (Korea, Republic of); Bae, Jang Pyo; Kim, Namkug; Chang, Yongjun; Seo, Joon Beom [University of Ulsan College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Lee, Ho Yun; Lee, Kyung Soo [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Chung, Man Pyo; Park, Hye Yun [Sungkyunkwan University School of Medicine, Department of Pulmonology, Samsung Medical Center, Seoul (Korea, Republic of)

    2016-05-15

    To evaluate automated texture-based segmentation of dual-energy CT (DECT) images in diffuse interstitial lung disease (DILD) patients and prognostic stratification by overlapping morphologic and perfusion information of total lung. Suspected DILD patients scheduled for surgical biopsy were prospectively included. Texture patterns included ground-glass opacity (GGO), reticulation and consolidation. Pattern- and perfusion-based CT measurements were assessed to extract quantitative parameters. Accuracy of texture-based segmentation was analysed. Correlations between CT measurements and pulmonary function test or 6-minute walk test (6MWT) were calculated. Parameters of idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP) and non-IPF/UIP were compared. Survival analysis was performed. Overall accuracy was 90.47 % for whole lung segmentation. Correlations between mean iodine values of total lung, 50-97.5th (%) attenuation and forced vital capacity or 6MWT were significant. Volume of GGO, reticulation and consolidation had significant correlation with DLco or SpO{sub 2} on 6MWT. Significant differences were noted between IPF/UIP and non-IPF/UIP in 6MWT distance, mean iodine value of total lung, 25-75th (%) attenuation and entropy. IPF/UIP diagnosis, GGO ratio, DILD extent, 25-75th (%) attenuation and SpO{sub 2} on 6MWT showed significant correlations with survival. DECT combined with pattern analysis is useful for analysing DILD and predicting survival by provision of morphology and enhancement. (orig.)

  1. An experimental study on the acute myocardial infarction with CT perfusion scans

    International Nuclear Information System (INIS)

    Liu Yuanjian; Yan Weiqiang; Wang Chenglin; Liu Pengcheng; Feng Xiaoyuan; Shen Tianzhen; Chen Xingrong

    2004-01-01

    Objective: To determine the reliability of CT perfusion scans and its parameters of γ-variate curve in evaluating the acute myocardial infarction for clinical reference of diagnosis on coronary artery disease and myocardial infarction. Methods: Imatron C-150 electron beam CT (EBCT) were used to scan a hydrodynamic model which could mimic a change of contrast medium by intravenous injection in vivo. Then 6 adult canines were employed in the experiment with thoracic operation, and branches of the anterior descending and circumflex of left coronary arteries (LCA) were ligated so that myocardial infarction was made out. After intravenous administration of contrast medium, the hearts were scanned with perfusion EBCT and γ-variate curves were manifested. Some heterogeneities and differentiations between the normality and the infarctions were put forward when the parameters of all these curves were analyzed and statistically processed. Two myocardial infarctions were also verified by SPECT, and all the samples stained with TTC method were compared with those on the perfusion images. The pathological study with optical microscope and electron microscope were further carried on. Results: The ascending slopes of γ-variate curves were different in the perfusion quantity. The normal curve of canine myocardium showed a somewhat quick ascending pattern first, and then a gradual descending pattern successively, with the ascending time of about 10-13 s, ascending CT value of about 34-37 HU, and peak CT value of about 70-81 HU. Whereas the curve on myocardial infarction demonstrated a prolonged ascending time of about 19.9 s, diminished ascending CT value of only about 20 HU, and peak CT value of about 53.8 HU, which were significantly different from the normality (P<0.05). Conclusion: There are some differences in γ-variate curves between normal myocardium and myocardial infarction, which can be detected by CT perfusion scan. (authors)

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

    International Nuclear Information System (INIS)

    Suga, K.; Yasuhiko, K.; Iwanaga, H.; Tokuda, O.; Matsunaga, N.

    2009-01-01

    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

  3. 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

  4. Pancreas tumor model in rabbit imaged by perfusion CT scans

    Science.gov (United States)

    Gunn, Jason; Tichauer, Kenneth; Moodie, Karen; Kane, Susan; Hoopes, Jack; Stewart, Errol E.; Hadway, Jennifer; Lee, Ting-Yim; Pereira, Stephen P.; Pogue, Brian W.

    2013-03-01

    The goal of this work was to develop and validate a pancreas tumor animal model to investigate the relationship between photodynamic therapy (PDT) effectiveness and photosensitizer drug delivery. More specifically, this work lays the foundation for investigating the utility of dynamic contrast enhanced blood perfusion imaging to be used to inform subsequent PDT. A VX2 carcinoma rabbit cell line was grown in the tail of the pancreas of three New Zealand White rabbits and approximately 3-4 weeks after implantation the rabbits were imaged on a CT scanner using a contrast enhanced perfusion protocol, providing parametric maps of blood flow, blood volume, mean transit time, and vascular permeability surface area product.

  5. CT myocardial perfusion and coronary CT angiography: Influence of coronary calcium on a stress-rest protocol.

    Science.gov (United States)

    Ladeiras-Lopes, Ricardo; Bettencourt, Nuno; Ferreira, Nuno; Sampaio, Francisco; Pires-Morais, Gustavo; Santos, Lino; Melica, Bruno; Rodrigues, Alberto; Braga, Pedro; Leite-Moreira, Adelino; Silva-Cardoso, José; Gama, Vasco

    2016-01-01

    High amounts of coronary artery calcium limit image quality and diagnostic accuracy of multidetector computed tomography (MDCT) angiography (CTA) regarding the assessment of obstructive coronary artery disease (CAD). CT myocardial perfusion imaging may represent an opportunity to overcome this limitation. To explore the additive value of CT myocardial perfusion to CTA depending on the patient's calcium score and in comparison to the reference standard of invasive coronary angiography plus fractional flow reserve (FFR) measurement. Symptomatic patients with intermediate pretest probability of CAD were prospectively recruited and underwent both cardiac MDCT (64-slice scanner, retrospectively-gated stress-rest protocol) and invasive coronary angiography including FFR assessment. We defined hemodynamically significant CAD by the presence of occlusive or subocclusive (99%) stenosis, >50% stenosis in left main or FFR≤0.80. Stress CT myocardial perfusion imaging was performed in all patients in addition to CTA. The additive value of CT myocardial perfusion to rule in or rule out the presence of hemodynamically relevant stenosis on a per-patient basis was assessed and analyzed relative to the patient's calcium score. 95 patients were included in the analysis (62 ± 8.2 years, 68%males). Hemodynamically significant CAD was present in 42 patients. Sixty-four patients had a fully evaluable CTA examination. Per-patient, CTA alone had a sensitivity, specificity and AUC of 100%, 59% and 0.79 respectively (77% patients correctly classified). Adding CT myocardial perfusion to evaluate uninterpretable vessel territories in CTA in 66 patients with a calcium score>100 yielded a sensitivity of 88%, a specificity of 74% and an AUC of 0.81 (81% patients correctly classified), and in 52 patients with a calcium score>400 sensitivity was 91%, specificity 70%, and AUC 0.80 (82% patients correctly classified, p = 0.733 versus using perfusion imaging in all patients). From a pragmatic

  6. The dream of a one-stop-shop: Meta-analysis on myocardial perfusion CT.

    Science.gov (United States)

    Pelgrim, Gert Jan; Dorrius, Monique; Xie, Xueqian; den Dekker, Martijn A M; Schoepf, U Joseph; Henzler, Thomas; Oudkerk, Matthijs; Vliegenthart, Rozemarijn

    2015-12-01

    To determine the diagnostic performance of computed tomography (CT) perfusion techniques for the detection of functionally relevant coronary artery disease (CAD) in comparison to reference standards, including invasive coronary angiography (ICA), single photon emission computed tomography (SPECT), and magnetic resonance imaging (MRI). PubMed, Web of Knowledge and Embase were searched from January 1, 1998 until July 1, 2014. The search yielded 9475 articles. After duplicate removal, 6041 were screened on title and abstract. The resulting 276 articles were independently analyzed in full-text by two reviewers, and included if the inclusion criteria were met. The articles reporting diagnostic parameters including true positive, true negative, false positive and false negative were subsequently evaluated for the meta-analysis. Results were pooled according to CT perfusion technique, namely snapshot techniques: single-phase rest, single-phase stress, single-phase dual-energy stress and combined coronary CT angiography [rest] and single-phase stress, as well the dynamic technique: dynamic stress CT perfusion. Twenty-two articles were included in the meta-analysis (1507 subjects). Pooled per-patient sensitivity and specificity of single-phase rest CT compared to rest SPECT were 89% (95% confidence interval [CI], 82-94%) and 88% (95% CI, 78-94%), respectively. Vessel-based sensitivity and specificity of single-phase stress CT compared to ICA-based >70% stenosis were 82% (95% CI, 64-92%) and 78% (95% CI, 61-89%). Segment-based sensitivity and specificity of single-phase dual-energy stress CT in comparison to stress MRI were 75% (95% CI, 60-85%) and 95% (95% CI, 80-99%). Segment-based sensitivity and specificity of dynamic stress CT perfusion compared to stress SPECT were 77% (95% CI, 67-85) and 89% (95% CI, 78-95%). For combined coronary CT angiography and single-phase stress CT, vessel-based sensitivity and specificity in comparison to ICA-based >50% stenosis were 84% (95

  7. A study of whole brain perfusion CT and CT angiography in hyperacute and acute cerebral infarction

    International Nuclear Information System (INIS)

    Zhang Yonghai; Bai Junhu; Zhang Ming; Yang Guocai; Tang Guibo; Fang Jun; Shi Wei; Li Xinghua; Liu Suping; Lu Qing; Tang Jun

    2005-01-01

    Objective: To evaluate the diagnostic value of whole-brain perfusion blood volume-weighted CT imaging (PWCT) and simultaneous CT angiography (CTA) on early stage of cerebral ischemic infarction. Methods: Non-contrast CT (NCCT), CT perfusion-weighted imaging (PWCT) and delayed CT (DCT) were conducted on 20 cases of early ischemic infarction of whose onset time ranged from 2 to 24 hours. All cases were reexamined with CT or MRI one week to one month later. CT values and perfusion blood volume (PBV) of central and peripheral low perfusion areas as well as those of collateral side were measured. CTA was reconstructed with PWCT as source images to evaluate occlusion or stenosis of blood vessel, and DCT was used to detect the collateral circulation. Results: Of the 20 cases, NCCT, PWCT and CTA were negative in 10 cases in which 6 were confirmed as Transient Ischemic Attack (TIA) on reexamined CT and clinical features, and the other 4 were confirmed as lacunar infarction. For the remaining 10 cases, a comparison was made with ANOVA between low perfusion area (central, peripheral inside and outside) and collateral side. The difference was significant (P<0.01). However, no significant difference was revealed in the central, peripheral inside and outside areas. PBV values were significant in low perfusion area and collateral side (P<0.05). The area of the final infarction was larger than that of the low perfusion area, and the percentage of enlargement exhibited medium negative correlation to the time of ischemia. CTA indicated that 2 cases suffered from left middle cerebral artery occlusion, meanwhile anterior and middle branches of MCA in the other 3 cases were not identified. The sensitivity of NCCT, PWCT and CTA were 28.5%, 71.4% and 35.7% respectively. DCT indicated that 5 cases had asymmetrical blood vessels. Conclusion: The whole-brain perfusion-weighted CT imaging and simultaneous CT angiography (CTA) is p roved to be a simple, timesaving and effective method for the

  8. Stress myocardial perfusion imaging with multidetector CT

    NARCIS (Netherlands)

    A. Rossi (Alexia); D. Merkus (Daphne); E. Klotz (Ernst); N.R.A. Mollet (Nico); P.J. de Feyter (Pim); G.P. Krestin (Gabriel)

    2014-01-01

    textabstractComputed tomographic (CT) coronary angiography is a well-established, noninvasive imaging modality for detection of coronary stenosis, but it has limited accuracy in demonstrating whether a coronary stenosis is hemodynamically significant. An additional functional test is often required

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

    Science.gov (United States)

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

    2014-03-01

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

  10. [CT perfusion in patients after EICMA in the postoperative period].

    Science.gov (United States)

    Grigor'eva, E V; Luk'ianchikov, V A; Tokarev, A S; Krylov, V V

    2014-01-01

    To evaluate the influence of the EICMA on the circulation of the brain in patients with unilateral occlusion of the internal carotid artery (ICA) in the late postoperative period using CT perfusion. Ten patients with unilateral internal carotid artery occlusion and stenosis of the opposite ICA 50-60%, with a history of a single ischemic stroke were examined. All patients underwent pre-and postoperative CT angiography of the brachiocephalic and intracranial arteries and CT perfusion. We also compared the results of neurological examinations preoperatively and during the year after the intervention. The neurological data during the first year after surgery demonstrated an improvement of neurological status and quality of life in all patients. Preoperative CT perfusion showed the patchy decrease in the cerebral blood flow (CBF) to 18 ml/100 g/min (average of 44-56 ml/100 g/min) and increase in the mean transit time (MTT) to 7.2 s (normally less 6c) in all cases on the side of occlusion. The most susceptible to chronic ischemic changes was the frontal region, temporal and parietooccipital regions were affected to a lesser extent. Due to stenosis of the opposite ICA, minimum CBF of the cortex in the opposite hemisphere was 24 ml/100 g/min and MTT was increased to 5.6 s. Six months after the applying of EICMA, the significant improvement of CT perfusion was noted on the side of the anastomosis in all patients: an increase in CBF (at least 44 ml/100 g/min) and MTT reduction (up to 6.1s in the frontal region), as well as the "synchronization" of CBF and CBV in similar areas of the cerebral cortex of the right and left hemisphere. CT perfusion in the late postoperative period after applying EICMA in patients with unilateral ICA occlusion demonstrates not only changes of the cerebral perfusion on the side of the occlusion, but also the increased collateral blood flow of the cortex in both hemispheres, which significantly improves brain blood flow generally within 6-12 months

  11. CT of malignant choroidal melanoma - morphology and perfusion characteristics

    International Nuclear Information System (INIS)

    Heller, M.; Hagemann, J.; Jend, H.H.; Guthoff, R.

    1982-01-01

    The computed tomographic morphology of malignant choroidal melanoma and its perfusion characteristics are described. Thirty-three static and serial CT examinations made on 29 patients with choroidal melanoma, three with pseudotumors of the macula and one with choroidal metastasis revealed the choroidal melanoma to be usually a hyperdense, markedly perfused tumor, while the non-contrast, diagnostically undifferentiable pseudotumors and the choroidal metastasis, revealed no significant change in density after the administration of contrast material. Density values or perfusion characteristics of choroidal melanoma that are outside of the normal range are a result of secondary changes within the immediate surroundings of the tumor, such as detachment of the retina, tumor-induced glaucoma, or tumor necrosis. (orig.)

  12. CT of malignant choroidal melanoma - morphology and perfusion characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Heller, M.; Hagemann, J.; Jend, H.H.; Guthoff, R.

    1982-03-01

    The computed tomographic morphology of malignant choroidal melanoma and its perfusion characteristics are described. Thirty-three static and serial CT examinations made on 29 patients with choroidal melanoma, three with pseudotumors of the macula and one with choroidal metastasis revealed the choroidal melanoma to be usually a hyperdense, markedly perfused tumor, while the non-contrast, diagnostically undifferentiable pseudotumors and the choroidal metastasis, revealed no significant change in density after the administration of contrast material. Density values or perfusion characteristics of choroidal melanoma that are outside of the normal range are a result of secondary changes within the immediate surroundings of the tumor, such as detachment of the retina, tumor-induced glaucoma, or tumor necrosis.

  13. Volume perfusion CT imaging of cerebral vasospasm: diagnostic performance of different perfusion maps

    Energy Technology Data Exchange (ETDEWEB)

    Othman, Ahmed E. [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Eberhard Karls University Tuebingen, University Hospital Tuebingen, Department for Diagnostic and Interventional Radiology, Tuebingen (Germany); Afat, Saif; Nikoubashman, Omid; Mueller, Marguerite; Wiesmann, Martin; Brockmann, Carolin [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Schubert, Gerrit Alexander [RWTH Aachen University, Department of Neurosurgery, Aachen (Germany); Bier, Georg [Eberhard Karls University Tuebingen, University Hospital Tuebingen, Department for Diagnostic and Interventional Neuroradiology, Tuebingen (Germany); Brockmann, Marc A. [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); University Hospital Mainz, Department of Neuroradiology, Mainz (Germany)

    2016-08-15

    In this study, we aimed to evaluate the diagnostic performance of different volume perfusion CT (VPCT) maps regarding the detection of cerebral vasospasm compared to angiographic findings. Forty-one datasets of 26 patients (57.5 ± 10.8 years, 18 F) with subarachnoid hemorrhage and suspected cerebral vasospasm, who underwent VPCT and angiography within 6 h, were included. Two neuroradiologists independently evaluated the presence and severity of vasospasm on perfusion maps on a 3-point Likert scale (0 - no vasospasm, 1 - vasospasm affecting <50 %, 2 - vasospasm affecting >50 % of vascular territory). A third neuroradiologist independently assessed angiography for the presence and severity of vasospasm on a 3-point Likert scale (0 - no vasospasm, 1 - vasospasm affecting < 50 %, 2 - vasospasm affecting > 50 % of vessel diameter). Perfusion maps of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to drain (TTD) were evaluated regarding diagnostic accuracy for cerebral vasospasm with angiography as reference standard. Correlation analysis of vasospasm severity on perfusion maps and angiographic images was performed. Furthermore, inter-reader agreement was assessed regarding findings on perfusion maps. Diagnostic accuracy for TTD and MTT was significantly higher than for all other perfusion maps (TTD, AUC = 0.832; MTT, AUC = 0.791; p < 0.001). TTD revealed higher sensitivity than MTT (p = 0.007). The severity of vasospasm on TTD maps showed significantly higher correlation levels with angiography than all other perfusion maps (p ≤ 0.048). Inter-reader agreement was (almost) perfect for all perfusion maps (kappa ≥ 0.927). The results of this study indicate that TTD maps have the highest sensitivity for the detection of cerebral vasospasm and highest correlation with angiography regarding the severity of vasospasm. (orig.)

  14. Perfusion CT can predict tumoral grading of pancreatic adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    D’Onofrio, M., E-mail: mirko.donofrio@univr.it [Department of Radiology, University Hospital G.B. Rossi Piazzale L.A. Scuro 10, 37134 University of Verona, Verona (Italy); Gallotti, A. [Department of Radiology, University Hospital G.B. Rossi Piazzale L.A. Scuro 10, 37134 University of Verona, Verona (Italy); Mantovani, W. [Department of Medicine and Public Health, University Hospital G.B. Rossi Piazzale L.A. Scuro 10, 37134 University of Verona, Verona (Italy); Crosara, S. [Department of Radiology, University Hospital G.B. Rossi Piazzale L.A. Scuro 10, 37134 University of Verona, Verona (Italy); Manfrin, E. [Department of Pathology, University Hospital G.B. Rossi Piazzale L.A. Scuro 10, 37134 University of Verona, Verona (Italy); Falconi, M. [Department of Surgery, University Hospital G.B. Rossi Piazzale L.A. Scuro 10, 37134 University of Verona, Verona (Italy); Ventriglia, A.; Zamboni, G.A.; Manfredi, R.; Pozzi Mucelli, R. [Department of Radiology, University Hospital G.B. Rossi Piazzale L.A. Scuro 10, 37134 University of Verona, Verona (Italy)

    2013-02-15

    Objectives: To describe perfusion CT features of locally advanced pancreatic ductal adenocarcinoma and to evaluate correlation with tumor grading. Methods: Thirty-two patients with locally advanced pancreatic adenocarcinoma were included in this study. Lesions were evaluated by P-CT and biopsy after patient's informed consent. P-CT parameters have been assessed on a large single and on 6 small intratumoral ROIs. Values obtained have been compared and related to the tumor grading using Mann–Whitney U test. Sensibility, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy in predicting tumor grading have been calculated for cut-off values chosen by using ROC curves. Results: Out of 32 lesions, 12 were classified as low grade and 20 as high grade. A statistically significant difference between high and low grade neoplasms were demonstrated for PEI and BV parameters. PEI and BV cut-off values were respectively 17.8 HU and 14.8 ml/100 g. PEI identified high grade neoplasms with a 65% sensitivity, 92% specificity, 93% PPV, 61% NPV and 75% accuracy. BV identified high grade neoplasms with a 80% sensitivity, 75% specificity, 84% PPV, 69% NPV, 78% accuracy. Considering both PEI and BV, P-CT identified high grade lesions with a 60% sensitivity, 100% specificity, 100% PPV, 60% NPV and 75% accuracy. Conclusions: PEI and BV perfusion CT parameters proved their efficiency in identifying high grade pancreatic adenocarcinoma.

  15. Impact of CT perfusion imaging on the assessment of peripheral chronic pulmonary thromboembolism: clinical experience in 62 patients.

    Science.gov (United States)

    Le Faivre, Julien; Duhamel, Alain; Khung, Suonita; Faivre, Jean-Baptiste; Lamblin, Nicolas; Remy, Jacques; Remy-Jardin, Martine

    2016-11-01

    To evaluate the impact of CT perfusion imaging on the detection of peripheral chronic pulmonary embolisms (CPE). 62 patients underwent a dual-energy chest CT angiographic examination with (a) reconstruction of diagnostic and perfusion images; (b) enabling depiction of vascular features of peripheral CPE on diagnostic images and perfusion defects (20 segments/patient; total: 1240 segments examined). The interpretation of diagnostic images was of two types: (a) standard (i.e., based on cross-sectional images alone) or (b) detailed (i.e., based on cross-sectional images and MIPs). The segment-based analysis showed (a) 1179 segments analyzable on both imaging modalities and 61 segments rated as nonanalyzable on perfusion images; (b) the percentage of diseased segments was increased by 7.2 % when perfusion imaging was compared to the detailed reading of diagnostic images, and by 26.6 % when compared to the standard reading of images. At a patient level, the extent of peripheral CPE was higher on perfusion imaging, with a greater impact when compared to the standard reading of diagnostic images (number of patients with a greater number of diseased segments: n = 45; 72.6 % of the study population). Perfusion imaging allows recognition of a greater extent of peripheral CPE compared to diagnostic imaging. • Dual-energy computed tomography generates standard diagnostic imaging and lung perfusion analysis. • Depiction of CPE on central arteries relies on standard diagnostic imaging. • Detection of peripheral CPE is improved by perfusion imaging.

  16. 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.)

  17. Study on application of spiral CT perfusion technology in the diagnosis of acute pancreatitis

    Directory of Open Access Journals (Sweden)

    Xiao-Sen Zhou

    2017-06-01

    Full Text Available Objective: To explore the application value of spiral CT perfusion technology in the diagnosis of acute pancreatitis (AP. Methods: A total of 78 patients with AP who were admitted in our hospital from September, 2014 to September, 2016 were included in the study. The velocity method was used to detect S-Amy and U-Amy. The emulsion enhancement velocity scattering turbidimetry was used to detect CRP. ELISA was used to detect D-D. The patients in the control group were performed with abdomen CT, while AP patients were performed with 64 slice spiral CT. The most integrated layer of pancreas display was regarded as the perfusion weighted imaging scanning layer, and CT perfusion scanning was performed. BF, BV, MTT, and PS were calculated. Results: S-Amy, U-Amy, CRP, and D-D in AP patients were significantly higher than those in the control group. With the disease progression, S-Amy and U-Amy were significantly reduced, while CRP and D-D were significantly elevated. BF and BV in AP patients were significantly lower than those in the control group, and those in SAP patients were significantly lower than those in MAP patients. With the elevation of CT grading, BF and BV were significantly reduced, while the comparison of MTT and PS among the various grading was not statistically significant. Conclusions: The pancreas perfusion in AP patients is in a low perfusion state. BF and BV are negatively correlated with the severity degree of AP, which can predict the prognosis. BF and BV in combined with the serum S-Amy, U-Amy, CRP, and D-D can provide a forceful evidence for the diagnosis, treatment, and condition evaluation of AP.

  18. EFFECT ON PERFUSION VALUES OF SAMPLING INTERVAL OF CT PERFUSION ACQUISITIONS IN NEUROENDOCRINE LIVER METASTASES AND NORMAL LIVER

    Science.gov (United States)

    Ng, Chaan S.; Hobbs, Brian P.; Wei, Wei; Anderson, Ella F.; Herron, Delise H.; Yao, James C.; Chandler, Adam G.

    2014-01-01

    Objective To assess the effects of sampling interval (SI) of CT perfusion acquisitions on CT perfusion values in normal liver and liver metastases from neuroendocrine tumors. Methods CT perfusion in 16 patients with neuroendocrine liver metastases were analyzed by distributed parameter modeling to yield tissue blood flow, blood volume, mean transit time, permeability, and hepatic arterial fraction, for tumor and normal liver. CT perfusion values for the reference sampling interval of 0.5s (SI0.5) were compared with those of SI datasets of 1s, 2s, 3s and 4s, using mixed-effects model analyses. Results Increases in SI beyond 1s were associated with significant and increasing departures of CT perfusion parameters from reference values at SI0.5 (p≤0.0009). CT perfusion values deviated from reference with increasing uncertainty with increasing SIs. Findings for normal liver were concordant. Conclusion Increasing SIs beyond 1s yield significantly different CT perfusion parameter values compared to reference values at SI0.5. PMID:25626401

  19. CT perfusion technique for assessment of early kidney allograft dysfunction: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Helck, A.; Notohamiprodjo, M.; Schoen, F.; Nikolaou, K.; Clevert, D.A.; Reiser, M.; Becker, C. [Ludwig-Maximilians-University of Munich, Department of Clinical Radiology, University Hospitals Grosshadern, Munich (Germany); Wessely, M.; Schoenermarck, U.; Fischereder, M. [Ludwig-Maximilians-University of Munich, Department of Internal Medicine IV, Nephrology, University Hospitals Grosshadern, Munich (Germany); Klotz, E. [Siemens Healthcare, Computed Tomography, Forchheim (Germany)

    2013-09-15

    To assess the benefit of quantitative computed tomography (CT) perfusion for differentiating acute tubular necrosis (ATN) and acute rejection (AR) in kidney allografts. Twenty-two patients with acute kidney allograft dysfunction caused by either AR (n = 6) or ATN (n = 16) were retrospectively included in the study. All patients initially underwent a multiphase CT angiography (CTA) protocol (12 phases, one phase every 3.5 s) covering the whole graft to exclude acute postoperative complications. Multiphase CT dataset and dedicated software were used to calculate renal blood flow. Renal biopsy or clinical course of disease served as the standard of reference. Mean effective radiation dose and mean amount of contrast media were calculated. Renal blood flow values were significantly lower (P = 0.001) in allografts undergoing AR (48.3 {+-} 21 ml/100 ml/min) compared with those with ATN (77.5 {+-} 21 ml/100 ml/min). No significant difference (P = 0.71) was observed regarding creatinine level with 5.65 {+-} 3.1 mg/dl in AR and 5.3 {+-} 1.9 mg/dl in ATN. The mean effective radiation dose of the CT perfusion protocol was 13.6 {+-} 5.2 mSv; the mean amount of contrast media applied was 34.5 {+-} 5.1 ml. All examinations were performed without complications. CT perfusion of kidney allografts may help to differentiate between ATN and rejection. (orig.)

  20. Calibration free beam hardening correction for cardiac CT perfusion imaging

    Science.gov (United States)

    Levi, Jacob; Fahmi, Rachid; Eck, Brendan L.; Fares, Anas; Wu, Hao; Vembar, Mani; Dhanantwari, Amar; Bezerra, Hiram G.; Wilson, David L.

    2016-03-01

    Myocardial perfusion imaging using CT (MPI-CT) and coronary CTA have the potential to make CT an ideal noninvasive gate-keeper for invasive coronary angiography. However, beam hardening artifacts (BHA) prevent accurate blood flow calculation in MPI-CT. BH Correction (BHC) methods require either energy-sensitive CT, not widely available, or typically a calibration-based method. We developed a calibration-free, automatic BHC (ABHC) method suitable for MPI-CT. The algorithm works with any BHC method and iteratively determines model parameters using proposed BHA-specific cost function. In this work, we use the polynomial BHC extended to three materials. The image is segmented into soft tissue, bone, and iodine images, based on mean HU and temporal enhancement. Forward projections of bone and iodine images are obtained, and in each iteration polynomial correction is applied. Corrections are then back projected and combined to obtain the current iteration's BHC image. This process is iterated until cost is minimized. We evaluate the algorithm on simulated and physical phantom images and on preclinical MPI-CT data. The scans were obtained on a prototype spectral detector CT (SDCT) scanner (Philips Healthcare). Mono-energetic reconstructed images were used as the reference. In the simulated phantom, BH streak artifacts were reduced from 12+/-2HU to 1+/-1HU and cupping was reduced by 81%. Similarly, in physical phantom, BH streak artifacts were reduced from 48+/-6HU to 1+/-5HU and cupping was reduced by 86%. In preclinical MPI-CT images, BHA was reduced from 28+/-6 HU to less than 4+/-4HU at peak enhancement. Results suggest that the algorithm can be used to reduce BHA in conventional CT and improve MPI-CT accuracy.

  1. A 4D Digital Phantom for Patient-Specific Simulation of Brain CT Perfusion Protocols

    NARCIS (Netherlands)

    Boom, R. van den; Manniesing, R.; Oei, M.T.H.; Woude, W.J. van der; Smit, E.J.; Laue, H.O.A.; Ginneken, B. van; Prokop, M.

    2014-01-01

    Purpose Optimizing CT brain perfusion protocols is a challenge because of the complex interaction between image acquisition, calculation of perfusion data and patient hemodynamics. Several digital phantoms have been developed to avoid unnecessary patient exposure or suboptimum choice of parameters.

  2. Beam hardening correction in CT myocardial perfusion measurement

    Science.gov (United States)

    So, Aaron; Hsieh, Jiang; Li, Jian-Ying; Lee, Ting-Yim

    2009-05-01

    This paper presents a method for correcting beam hardening (BH) in cardiac CT perfusion imaging. The proposed algorithm works with reconstructed images instead of projection data. It applies thresholds to separate low (soft tissue) and high (bone and contrast) attenuating material in a CT image. The BH error in each projection is estimated by a polynomial function of the forward projection of the segmented image. The error image is reconstructed by back-projection of the estimated errors. A BH-corrected image is then obtained by subtracting a scaled error image from the original image. Phantoms were designed to simulate the BH artifacts encountered in cardiac CT perfusion studies of humans and animals that are most commonly used in cardiac research. These phantoms were used to investigate whether BH artifacts can be reduced with our approach and to determine the optimal settings, which depend upon the anatomy of the scanned subject, of the correction algorithm for patient and animal studies. The correction algorithm was also applied to correct BH in a clinical study to further demonstrate the effectiveness of our technique.

  3. Myocardial perfusion imaging using SPECT/CT and PET/CT; Myokardperfusionsszintigrafie mit SPECT/CT und PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Hacker, Marcus; Uebleis, C. [Klinik und Poliklinik fuer Nuklearmedizin, Klinikum der Univ. Muenchen (Germany)

    2010-06-15

    With technical progress coronary CT angiography is increasingly accepted as a noninvasive alternative in morphological imaging. However, image quality and interpretation are still influenced by various factors like blooming artifacts, misregistration and the experience of the interpreter. The combination with stress-rest myocardial perfusion SPECT or PET as a hybrid scanner or two standalone scanners enables comprehensive noninvasive anatomical and functional imaging of the heart as well as three dimensional image fusion. Hybrid-imaging is feasible with today's commercially available software packages but still requires time demanding manual intervention and experienced interpretation. PET investigations, either in replacement of SPECT for perfusion measurements, or in addition with new biomarkers will provide even more impact to hybrid imaging in future. (orig.)

  4. Quantitative dual energy CT measurements in rabbit VX2 liver tumors: Comparison to perfusion CT measurements and histopathological findings

    International Nuclear Information System (INIS)

    Zhang, Long Jiang; Wu, Shengyong; Wang, Mei; Lu, Li; Chen, Bo; Jin, Lixin; Wang, Jiandong; Larson, Andrew C.; Lu, Guang Ming

    2012-01-01

    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. Towards robust deconvolution of low-dose perfusion CT: Sparse perfusion deconvolution using online dictionary learning

    Science.gov (United States)

    Fang, Ruogu; Chen, Tsuhan; Sanelli, Pina C.

    2014-01-01

    Computed tomography perfusion (CTP) is an important functional imaging modality in the evaluation of cerebrovascular diseases, particularly in acute stroke and vasospasm. However, the post-processed parametric maps of blood flow tend to be noisy, especially in low-dose CTP, due to the noisy contrast enhancement profile and the oscillatory nature of the results generated by the current computational methods. In this paper, we propose a robust sparse perfusion deconvolution method (SPD) to estimate cerebral blood flow in CTP performed at low radiation dose. We first build a dictionary from high-dose perfusion maps using online dictionary learning and then perform deconvolution-based hemodynamic parameters estimation on the low-dose CTP data. Our method is validated on clinical data of patients with normal and pathological CBF maps. The results show that we achieve superior performance than existing methods, and potentially improve the differentiation between normal and ischemic tissue in the brain. PMID:23542422

  6. Validation of myocardial perfusion quantification by dynamic CT in an ex-vivo porcine heart model

    NARCIS (Netherlands)

    Pelgrim, Gert Jan; Das, Marco; van Tuijl, Sjoerd; van Assen, Marly; Prinzen, Frits W; Stijnen, Marco; Oudkerk, Matthijs; Wildberger, Joachim E; Vliegenthart, Rozemarijn

    2017-01-01

    To test the accuracy of quantification of myocardial perfusion imaging (MPI) using computed tomography (CT) in ex-vivo porcine models. Five isolated porcine hearts were perfused according to Langendorff. Hearts were perfused using retrograde flow through the aorta and blood flow, blood pressure and

  7. A 4D CT digital phantom of an individual human brain for perfusion analysis

    NARCIS (Netherlands)

    Manniesing, Rashindra; Brune, Christoph; van Ginneken, Bram; Prokop, Mathias

    2016-01-01

    Brain perfusion is of key importance to assess brain function. Modern CT scanners can acquire perfusion maps of the cerebral parenchyma in vivo at submillimeter resolution. These perfusion maps give insights into the hemodynamics of the cerebral parenchyma and are critical for example for treatment

  8. Development of an Ex Vivo, Beating Heart Model for CT Myocardial Perfusion.

    Science.gov (United States)

    Pelgrim, Gert Jan; Das, Marco; Haberland, Ulrike; Slump, Cees; Handayani, Astri; van Tuijl, Sjoerd; Stijnen, Marco; Klotz, Ernst; Oudkerk, Matthijs; Wildberger, Joachim E; Vliegenthart, Rozemarijn

    2015-01-01

    To test the feasibility of a CT-compatible, ex vivo, perfused porcine heart model for myocardial perfusion CT imaging. One porcine heart was perfused according to Langendorff. Dynamic perfusion scanning was performed with a second-generation dual source CT scanner. Circulatory parameters like blood flow, aortic pressure, and heart rate were monitored throughout the experiment. Stenosis was induced in the circumflex artery, controlled by a fractional flow reserve (FFR) pressure wire. CT-derived myocardial perfusion parameters were analysed at FFR of 1 to 0.10/0.0. CT images did not show major artefacts due to interference of the model setup. The pacemaker-induced heart rhythm was generally stable at 70 beats per minute. During most of the experiment, blood flow was 0.9-1.0 L/min, and arterial pressure varied between 80 and 95 mm/Hg. Blood flow decreased and arterial pressure increased by approximately 10% after inducing a stenosis with FFR ≤ 0.50. Dynamic perfusion scanning was possible across the range of stenosis grades. Perfusion parameters of circumflex-perfused myocardial segments were affected at increasing stenosis grades. An adapted Langendorff porcine heart model is feasible in a CT environment. This model provides control over physiological parameters and may allow in-depth validation of quantitative CT perfusion techniques.

  9. Performance comparison between static and dynamic cardiac CT on perfusion quantitation and patient classification tasks

    Science.gov (United States)

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

    2015-03-01

    Cardiac CT acquisitions for perfusion assessment can be performed in a dynamic or static mode. In this simulation study, we evaluate the relative classification and quantification performance of these modes for assessing myocardial blood flow (MBF). In the dynamic method, a series of low dose cardiac CT acquisitions yields data on contrast bolus dynamics over time; these data are fit with a model to give a quantitative MBF estimate. In the static method, a single CT acquisition is obtained, and the relative CT numbers in the myocardium are used to infer perfusion states. The static method does not directly yield a quantitative estimate of MBF, but these estimates can be roughly approximated by introducing assumed linear relationships between CT number and MBF, consistent with the ways such images are typically visually interpreted. Data obtained by either method may be used for a variety of clinical tasks, including 1) stratifying patients into differing categories of ischemia and 2) using the quantitative MBF estimate directly to evaluate ischemic disease severity. Through simulations, we evaluate the performance on each of these tasks. The dynamic method has very low bias in MBF estimates, making it particularly suitable for quantitative estimation. At matched radiation dose levels, ROC analysis demonstrated that the static method, with its high bias but generally lower variance, has superior performance in stratifying patients, especially for larger patients.

  10. Impact of CT perfusion imaging on the assessment of peripheral chronic pulmonary thromboembolism: clinical experience in 62 patients

    Energy Technology Data Exchange (ETDEWEB)

    Le Faivre, Julien; Khung, Suonita; Faivre, Jean-Baptiste; Remy, Jacques; Remy-Jardin, Martine [University of Lille, Department of Thoracic Imaging, Hospital Calmette, Lille (France); Duhamel, Alain [University of Lille, Department of Biostatistics, Lille (France); Lamblin, Nicolas [University of Lille, Department of Cardiology, Cardiology Hospital, Lille (France)

    2016-11-15

    To evaluate the impact of CT perfusion imaging on the detection of peripheral chronic pulmonary embolisms (CPE). 62 patients underwent a dual-energy chest CT angiographic examination with (a) reconstruction of diagnostic and perfusion images; (b) enabling depiction of vascular features of peripheral CPE on diagnostic images and perfusion defects (20 segments/patient; total: 1240 segments examined). The interpretation of diagnostic images was of two types: (a) standard (i.e., based on cross-sectional images alone) or (b) detailed (i.e., based on cross-sectional images and MIPs). The segment-based analysis showed (a) 1179 segments analyzable on both imaging modalities and 61 segments rated as nonanalyzable on perfusion images; (b) the percentage of diseased segments was increased by 7.2 % when perfusion imaging was compared to the detailed reading of diagnostic images, and by 26.6 % when compared to the standard reading of images. At a patient level, the extent of peripheral CPE was higher on perfusion imaging, with a greater impact when compared to the standard reading of diagnostic images (number of patients with a greater number of diseased segments: n = 45; 72.6 % of the study population). Perfusion imaging allows recognition of a greater extent of peripheral CPE compared to diagnostic imaging. (orig.)

  11. Functional Assessment of Coronary Artery Disease Using Whole-Heart Dynamic Computed Tomographic Perfusion.

    Science.gov (United States)

    Hubbard, Logan; Ziemer, Benjamin; Lipinski, Jerry; Sadeghi, Bahman; Javan, Hanna; Groves, Elliott M; Malkasian, Shant; Molloi, Sabee

    2016-12-01

    Computed tomographic (CT) angiography is an important tool for the evaluation of coronary artery disease but often correlates poorly with myocardial ischemia. Current dynamic CT perfusion techniques can assess ischemia but have limited accuracy and deliver high radiation dose. Therefore, an accurate, low-dose, dynamic CT perfusion technique is needed. A total of 20 contrast-enhanced CT volume scans were acquired in 5 swine (40±10 kg) to generate CT angiography and perfusion images. Varying degrees of stenosis were induced using a balloon catheter in the proximal left anterior descending coronary artery, and a pressure wire was used for reference fractional flow reserve (FFR) measurement. Perfusion measurements were made with only 2 volume scans using a new first-pass analysis (FPA) technique and with 20 volume scans using an existing maximum slope model (MSM) technique. Perfusion (P) and FFR measurements were related by P FPA =1.01 FFR-0.03 (R 2 =0.85) and P MSM =1.03 FFR-0.03 (R 2 =0.80) for FPA and MSM techniques, respectively. Additionally, the effective radiation doses were calculated to be 2.64 and 26.4 mSv for FPA and MSM techniques, respectively. A new FPA-based dynamic CT perfusion technique was validated in a swine animal model. The results indicate that the FPA technique can potentially be used for improved anatomical and functional assessment of coronary artery disease at a relatively low radiation dose. © 2016 American Heart Association, Inc.

  12. Motion correction for improving the accuracy of dual-energy myocardial perfusion CT imaging

    Science.gov (United States)

    Pack, Jed D.; Yin, Zhye; Xiong, Guanglei; Mittal, Priya; Dunham, Simon; Elmore, Kimberly; Edic, Peter M.; Min, James K.

    2016-03-01

    Coronary Artery Disease (CAD) is the leading cause of death globally [1]. Modern cardiac computed tomography angiography (CCTA) is highly effective at identifying and assessing coronary blockages associated with CAD. The diagnostic value of this anatomical information can be substantially increased in combination with a non-invasive, low-dose, correlative, quantitative measure of blood supply to the myocardium. While CT perfusion has shown promise of providing such indications of ischemia, artifacts due to motion, beam hardening, and other factors confound clinical findings and can limit quantitative accuracy. In this paper, we investigate the impact of applying a novel motion correction algorithm to correct for motion in the myocardium. This motion compensation algorithm (originally designed to correct for the motion of the coronary arteries in order to improve CCTA images) has been shown to provide substantial improvements in both overall image quality and diagnostic accuracy of CCTA. We have adapted this technique for application beyond the coronary arteries and present an assessment of its impact on image quality and quantitative accuracy within the context of dual-energy CT perfusion imaging. We conclude that motion correction is a promising technique that can help foster the routine clinical use of dual-energy CT perfusion. When combined, the anatomical information of CCTA and the hemodynamic information from dual-energy CT perfusion should facilitate better clinical decisions about which patients would benefit from treatments such as stent placement, drug therapy, or surgery and help other patients avoid the risks and costs associated with unnecessary, invasive, diagnostic coronary angiography procedures.

  13. The role of perfusion CT in identifying stroke mimics in the emergency room: a case of status epilepticus presenting with perfusion CT alterations

    OpenAIRE

    Guerrero, Waldo R; Dababneh, Haitham; Eisenschenk, Stephan

    2012-01-01

    Emergency medicine physicians are often faced with the challenging task of differentiating true acute ischemic strokes from stroke mimics. We present a case that was initially diagnosed as acute stroke. However, perfusion CT and EEG eventually led to the final diagnosis of status epilepticus. This case further asserts the role of CT perfusion in the evaluation of patients with stroke mimics in the emergency room setting.

  14. 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.)

  15. CT perfusion of the liver during selective hepatic arteriography. Pure arterial blood perfusion of liver tumor and parenchyma

    International Nuclear Information System (INIS)

    Komemushi, Atsushi; Tanigawa, Noboru; Kojima, Hiroyuki; Kariya, Shuji; Sawada, Satoshi

    2003-01-01

    The purpose of this study was to quantify pure arterial blood perfusion of liver tumor and parenchyma by using CT perfusion during selective hepatic arteriography. A total of 44 patients underwent liver CT perfusion study by injection of contrast medium via the hepatic artery. CT-perfusion parameters including arterial blood flow, arterial blood volume, and arterial mean transit time in the liver parenchyma and liver tumor were calculated using the deconvolution method. The CT-perfusion parameters and vascularity of the tumor were compared. A complete analysis could be performed in 36 of the 44 patients. For liver tumor and liver parenchyma, respectively, arterial blood flow was 184.6±132.7 and 41.0±27.0 ml/min/100 g, arterial blood volume was 19.4±14.6 and 4.8±4.2 ml/100 g, and arterial mean transit time was 8.9±4.2 and 10.2±5.3 sec. Arterial blood flow and arterial blood volume correlated significantly with the vascularity of the tumor; however no correlation was detected between arterial mean transit time and the vascularity of the tumor. This technique could be used to quantify pure hepatic arterial blood perfusion. (author)

  16. Low dose dynamic myocardial CT perfusion using advanced iterative reconstruction

    Science.gov (United States)

    Eck, Brendan L.; Fahmi, Rachid; Fuqua, Christopher; Vembar, Mani; Dhanantwari, Amar; Bezerra, Hiram G.; Wilson, David L.

    2015-03-01

    Dynamic myocardial CT perfusion (CTP) can provide quantitative functional information for the assessment of coronary artery disease. However, x-ray dose in dynamic CTP is high, typically from 10mSv to >20mSv. We compared the dose reduction potential of advanced iterative reconstruction, Iterative Model Reconstruction (IMR, Philips Healthcare, Cleveland, Ohio) to hybrid iterative reconstruction (iDose4) and filtered back projection (FBP). Dynamic CTP scans were obtained using a porcine model with balloon-induced ischemia in the left anterior descending coronary artery to prescribed fractional flow reserve values. High dose dynamic CTP scans were acquired at 100kVp/100mAs with effective dose of 23mSv. Low dose scans at 75mAs, 50mAs, and 25mAs were simulated by adding x-ray quantum noise and detector electronic noise to the projection space data. Images were reconstructed with FBP, iDose4, and IMR at each dose level. Image quality in static CTP images was assessed by SNR and CNR. Blood flow was obtained using a dynamic CTP analysis pipeline and blood flow image quality was assessed using flow-SNR and flow-CNR. IMR showed highest static image quality according to SNR and CNR. Blood flow in FBP was increasingly over-estimated at reduced dose. Flow was more consistent for iDose4 from 100mAs to 50mAs, but was over-estimated at 25mAs. IMR was most consistent from 100mAs to 25mAs. Static images and flow maps for 100mAs FBP, 50mAs iDose4, and 25mAs IMR showed comparable, clear ischemia, CNR, and flow-CNR values. These results suggest that IMR can enable dynamic CTP at significantly reduced dose, at 5.8mSv or 25% of the comparable 23mSv FBP protocol.

  17. Stability of radiomic features in CT perfusion maps

    Science.gov (United States)

    Bogowicz, M.; Riesterer, O.; Bundschuh, R. A.; Veit-Haibach, P.; Hüllner, M.; Studer, G.; Stieb, S.; Glatz, S.; Pruschy, M.; Guckenberger, M.; Tanadini-Lang, S.

    2016-12-01

    This study aimed to identify a set of stable radiomic parameters in CT perfusion (CTP) maps with respect to CTP calculation factors and image discretization, as an input for future prognostic models for local tumor response to chemo-radiotherapy. Pre-treatment CTP images of eleven patients with oropharyngeal carcinoma and eleven patients with non-small cell lung cancer (NSCLC) were analyzed. 315 radiomic parameters were studied per perfusion map (blood volume, blood flow and mean transit time). Radiomics robustness was investigated regarding the potentially standardizable (image discretization method, Hounsfield unit (HU) threshold, voxel size and temporal resolution) and non-standardizable (artery contouring and noise threshold) perfusion calculation factors using the intraclass correlation (ICC). To gain added value for our model radiomic parameters correlated with tumor volume, a well-known predictive factor for local tumor response to chemo-radiotherapy, were excluded from the analysis. The remaining stable radiomic parameters were grouped according to inter-parameter Spearman correlations and for each group the parameter with the highest ICC was included in the final set. The acceptance level was 0.9 and 0.7 for the ICC and correlation, respectively. The image discretization method using fixed number of bins or fixed intervals gave a similar number of stable radiomic parameters (around 40%). The potentially standardizable factors introduced more variability into radiomic parameters than the non-standardizable ones with 56-98% and 43-58% instability rates, respectively. The highest variability was observed for voxel size (instability rate  >97% for both patient cohorts). Without standardization of CTP calculation factors none of the studied radiomic parameters were stable. After standardization with respect to non-standardizable factors ten radiomic parameters were stable for both patient cohorts after correction for inter-parameter correlations. Voxel size

  18. Radiation dose to radiosensitive organs in PET/CT myocardial perfusion examination using versatile optical fibre

    Science.gov (United States)

    Salasiah, M.; Nordin, A. J.; Fathinul Fikri, A. S.; Hishar, H.; Tamchek, N.; Taiman, K.; Ahmad Bazli, A. K.; Abdul-Rashid, H. A.; Mahdiraji, G. A.; Mizanur, R.; Noor, Noramaliza M.

    2013-05-01

    Cardiac positron emission tomography (PET) provides a precise method in order to diagnose obstructive coronary artery disease (CAD), compared to single photon emission tomography (SPECT). PET is suitable for obese and patients who underwent pharmacologic stress procedures. It has the ability to evaluate multivessel coronary artery disease by recording changes in left ventricular function from rest to peak stress and quantifying myocardial perfusion (in mL/min/g of tissue). However, the radiation dose to the radiosensitive organs has become crucial issues in the Positron Emission Tomography/Computed Tomography(PET/CT) scanning procedure. The objective of this study was to estimate radiation dose to radiosensitive organs of patients who underwent PET/CT myocardial perfusion examination at Centre for Diagnostic Nuclear Imaging, Universiti Putra Malaysia in one month period using versatile optical fibres (Ge-B-doped Flat Fibre) and LiF (TLD-100 chips). All stress and rest paired myocardial perfusion PET/CT scans will be performed with the use of Rubidium-82 (82Rb). The optic fibres were loaded into plastic capsules and attached to patient's eyes, thyroid and breasts prior to the infusion of 82Rb, to accommodate the ten cases for the rest and stress PET scans. The results were compared with established thermoluminescence material, TLD-100 chips. The result shows that radiation dose given by TLD-100 and Germanium-Boron-doped Flat Fiber (Ge-B-doped Flat Fiber) for these five organs were comparable to each other where the p>0.05. For CT scans,thyroid received the highest dose compared to other organs. Meanwhile, for PET scans, breasts received the highest dose.

  19. Dynamic CT perfusion image data compression for efficient parallel processing.

    Science.gov (United States)

    Barros, Renan Sales; Olabarriaga, Silvia Delgado; Borst, Jordi; van Walderveen, Marianne A A; Posthuma, Jorrit S; Streekstra, Geert J; van Herk, Marcel; Majoie, Charles B L M; Marquering, Henk A

    2016-03-01

    The increasing size of medical imaging data, in particular time series such as CT perfusion (CTP), requires new and fast approaches to deliver timely results for acute care. Cloud architectures based on graphics processing units (GPUs) can provide the processing capacity required for delivering fast results. However, the size of CTP datasets makes transfers to cloud infrastructures time-consuming and therefore not suitable in acute situations. To reduce this transfer time, this work proposes a fast and lossless compression algorithm for CTP data. The algorithm exploits redundancies in the temporal dimension and keeps random read-only access to the image elements directly from the compressed data on the GPU. To the best of our knowledge, this is the first work to present a GPU-ready method for medical image compression with random access to the image elements from the compressed data.

  20. The utility of first-pass perfusion CT in hyperacute ischemic stroke: early experience

    International Nuclear Information System (INIS)

    Lee, Tae Jin; Lee, Myeong Sub; Kim, Myung Soon; Hong, In Soo; Lee, Young Han; Lee, Ji Yong; Whang, Kum

    2003-01-01

    To evaluate the findings of first-pass perfusion CT in hyperacute stroke patients and to determine the relationship between a perfusion map and final infarct outcome. Thirty-five patients admitted with ischemic stroke within six hours of the onset of symptoms underwent conventional cerebral CT immediately followed by first-pass perfusion CT. Nineteen underwent follow-up CT or MRI, and three types of dynamic perfusion map-cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) - were evaluated by two radiologists. In these 19 patients, initial perfusion maps correlated with final infarct size, determined during follow-up studies. In all 35 patients, major large vessel perfusion abnormalities [middle cerebral artery - MCA MCA and anterior cerebral artery - ACA (n=2); posterior cerebral artery - PCA (n=8)] were detected. On first-pass perfusion maps depicting CBF and MTT, all lesions were detected, and CBF and delayed MTT values were recorded. CBV maps showed variable findings. In all 19 patients who were followed up, the final infarct size of perfusion abnormalities was less than that depicted on CBF and MTT maps, and similar to or much greater than that seen on CBV maps. First-pass perfusion CT scanning is a practical, rapid and advanced imaging technique. In hyperacute stroke patients, it provides important and reliable hemodynamic information as to which brain tissue is salvageable by thrombolytic therapy, and predicts outcome of such treatment

  1. First pass dual input volume CT-perfusion of lung lesions: The influence of the CT- value range settings on the perfusion values of benign and malignant entities.

    Science.gov (United States)

    Bohlsen, Dennis; Talakic, Emina; Fritz, Gerald A; Quehenberger, Franz; Tillich, Manfred; Schoellnast, Helmut

    2016-06-01

    To assess the influence of the lower threshold for segmentation of the volume of interest on the perfusion values in first-pass dual input volume CT-perfusion of lung lesions. Dual input maximum slope volume CT-perfusion was performed in 48 patients (mean age±standard deviation [SD], 68±10years; range, 46-87 years) who underwent subsequent CT-guided biopsy to evaluate a lung lesion. Using commercial perfusion software, a lower and upper threshold was set for determination of the CT-value range, which again determined the volume of interest for perfusion calculation. The pulmonary arterial flow (PAF), bronchial arterial flow (BAF), and perfusion index (PI; PAF/(PAF+BAF)) were calculated at following pre contrast CT value range settings: -80 to 150HU (setting 1), -200 to 150HU (setting 2), -300 to 150HU (setting 3), and -500 to 150HU (setting 4). Perfusion parameters were compared between benign (n, 15) and malignant (n, 33) lesions for each setting. Intraobserver- and interobserver reliability were calculated for setting 4. Median PAF was significantly higher in malignant lesions than in benign lesions for all settings (53-96 versus 29-62mL/min/100mL, PCT value range setting (PCT perfusion is statistically significantly higher in malignant than in benign lesion, whereas the measurements are influenced by the lower threshold of the CT value range setting. This has to be considered when using cutoff values provided in the literature for differentiation between benign and malignant lung lesions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Coronary CT angiography in coronary artery disease: Opportunities and challenges

    Directory of Open Access Journals (Sweden)

    Zhonghua Sun

    2016-06-01

    Full Text Available Coronary CT angiography is widely recognised as a reliable imaging modality for the diagnosis of coronary artery disease. Coronary CT angiography not only provides excellent visualisation of anatomical changes in the coronary artery with high diagnostic value in the detection of lumen stenosis or occlusion, but also offers quantitative characterisation of coronary plaque components. Furthermore, coronary CT angiography allows myocardial perfusion imaging with diagnostic value comparable to the reference standard method. Coronary CT angiography-derived haemodynamic analysis has the potential to evaluate functional significance of coronary lesions. This review article aims to provide an overview of clinical applications of coronary CT angiography in coronary artery disease.

  3. Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

    International Nuclear Information System (INIS)

    Hanson, Eric H.; Roach, Cayce J.; Ringdahl, Erik N.; Wynn, Brad L.; DeChancie, Sean M.; Mann, Nathan D.; Diamond, Alan S.; Orrison, William W.

    2011-01-01

    Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

  4. Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Eric H. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); Amigenics, Inc, Las Vegas, NV (United States); Roach, Cayce J. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); University of Nevada Las Vegas, School of Life Sciences, Las Vegas, NV (United States); Ringdahl, Erik N. [University of Nevada Las Vegas, Department of Psychology, Las Vegas, NV (United States); Wynn, Brad L. [Family Medicine Spokane, Spokane, WA (United States); DeChancie, Sean M.; Mann, Nathan D. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); Diamond, Alan S. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); Orrison, William W. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); University of Nevada School of Medicine, Department of Medical Education, Reno, NV (United States)

    2011-05-15

    Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

  5. Quantitative Myocardial Perfusion with Dynamic Contrast-Enhanced Imaging in MRI and CT: Theoretical Models and Current Implementation

    Directory of Open Access Journals (Sweden)

    G. J. Pelgrim

    2016-01-01

    Full Text Available Technological advances in magnetic resonance imaging (MRI and computed tomography (CT, including higher spatial and temporal resolution, have made the prospect of performing absolute myocardial perfusion quantification possible, previously only achievable with positron emission tomography (PET. This could facilitate integration of myocardial perfusion biomarkers into the current workup for coronary artery disease (CAD, as MRI and CT systems are more widely available than PET scanners. Cardiac PET scanning remains expensive and is restricted by the requirement of a nearby cyclotron. Clinical evidence is needed to demonstrate that MRI and CT have similar accuracy for myocardial perfusion quantification as PET. However, lack of standardization of acquisition protocols and tracer kinetic model selection complicates comparison between different studies and modalities. The aim of this overview is to provide insight into the different tracer kinetic models for quantitative myocardial perfusion analysis and to address typical implementation issues in MRI and CT. We compare different models based on their theoretical derivations and present the respective consequences for MRI and CT acquisition parameters, highlighting the interplay between tracer kinetic modeling and acquisition settings.

  6. Quantitative Myocardial Perfusion with Dynamic Contrast-Enhanced Imaging in MRI and CT: Theoretical Models and Current Implementation

    Science.gov (United States)

    Handayani, A.; Dijkstra, H.; Prakken, N. H. J.; Slart, R. H. J. A.; Oudkerk, M.; Van Ooijen, P. M. A.; Vliegenthart, R.; Sijens, P. E.

    2016-01-01

    Technological advances in magnetic resonance imaging (MRI) and computed tomography (CT), including higher spatial and temporal resolution, have made the prospect of performing absolute myocardial perfusion quantification possible, previously only achievable with positron emission tomography (PET). This could facilitate integration of myocardial perfusion biomarkers into the current workup for coronary artery disease (CAD), as MRI and CT systems are more widely available than PET scanners. Cardiac PET scanning remains expensive and is restricted by the requirement of a nearby cyclotron. Clinical evidence is needed to demonstrate that MRI and CT have similar accuracy for myocardial perfusion quantification as PET. However, lack of standardization of acquisition protocols and tracer kinetic model selection complicates comparison between different studies and modalities. The aim of this overview is to provide insight into the different tracer kinetic models for quantitative myocardial perfusion analysis and to address typical implementation issues in MRI and CT. We compare different models based on their theoretical derivations and present the respective consequences for MRI and CT acquisition parameters, highlighting the interplay between tracer kinetic modeling and acquisition settings. PMID:27088083

  7. Assessment of tumor grade and angiogenesis in colorectal cancer: whole-volume perfusion CT.

    Science.gov (United States)

    Sun, Hongliang; Xu, Yanyan; Yang, Qiang; Wang, Wu

    2014-06-01

    The preoperative evaluation of tumor grading and angiogenesis has important clinical implications in the treatment and prognosis of patients with colorectal cancers (CRCs). The aim of the present study was to assess tumor perfusion with 256-slice computed tomography (CT) using whole-volume perfusion technology before surgery, and to investigate the differences in the perfusion parameters among tumor grades and the correlation between perfusion parameters and pathologic results in CRC. Thirty-seven patients with CRC confirmed by endoscopic pathology underwent whole-volume perfusion CT assessments with a 256-slice CT and surgery. Quantitative values for blood flow, blood volume, and time to peak were determined using commercial software. After surgery, resected specimens were analyzed immunohistochemically with CD105 antibodies for the quantification of microvessel density (MVD). The difference in CT perfusion parameters and MVD among different tumor differentiation grades was evaluated by the Student-Newman-Keuls test. The correlations between CT perfusion parameters and MVD were evaluated using the Pearson correlation analysis. The mean blood flow was significantly different among well, moderately, and poorly differentiated groups (61.17 ± 17.97, 34.80 ± 13.06, and 22.24 ± 9.31 mL/minute/100 g, respectively; P .05). There was no significant correlation between CT perfusion parameters and MVD (r = 0.201, 0.295, and -0.178, respectively; P = .233, .076, and .292, respectively). CT whole-volume perfusion technology has the potential to evaluate pathologic differentiation grade of CRC before surgery. However, preoperative perfusion CT parameters do not reflect the MVD of CRC. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.

  8. Dynamic (4D) CT perfusion offers simultaneous functional and anatomical insights into pulmonary embolism resolution

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    Mirsadraee, Saeed, E-mail: saeed.mirsadraee@ed.ac.uk [Clinical Research Imaging Centre, Queen' s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ (United Kingdom); Reid, John H.; Connell, Martin [Clinical Research Imaging Centre, Queen' s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ (United Kingdom); MacNee, William; Hirani, Nikhil [The Queen' s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ (United Kingdom); Murchison, John T. [Department of Radiology, Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA (United Kingdom); Beek, Edwin J. van [Clinical Research Imaging Centre, Queen' s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ (United Kingdom)

    2016-10-15

    Objective: Resolution and long-term functional effects of pulmonary emboli are unpredictable. This study was carried out to assess persisting vascular bed perfusion abnormalities and resolution of arterial thrombus in patients with recent pulmonary embolism (PE). Methods and materials: 26 Patients were prospectively evaluated by dynamic (4D) contrast enhanced CT perfusion dynamic pulmonary CT perfusion. Intermittent volume imaging was performed every 1.5–1.7 s during breath-hold and perfusion values were calculated by maximum-slope technique. Thrombus load (modified Miller score; MMS) and ventricular diameter were determined. Perfusion maps were visually scored and correlated with residual endoluminal filling defects. Results: The mean initial thrombus load was 13.1 ± 4.6 MMS (3–16), and 1.2 ± 2.1 MMS (0–8) at follow up. From the 24 CTPs with diagnostic quality perfusion studies, normal perfusion was observed in 7 (29%), and mildly-severely abnormal in 17 (71%). In 15 patients with no residual thrombus on follow up CTPA, normal perfusion was observed in 6, and abnormal perfusion in 9. Perfusion was abnormal in all patients with residual thrombus on follow up CTPA. Pulmonary perfusion changes were classified as reduced (n = 4), delayed (systemic circulation pattern; n = 5), and absent (no-flow; n = 5). The right ventricle was dilated in 12/25 (48%) at presentation, and normal in all 26 follow up scans. Weak correlation was found between initial ventricular dilatation and perfusion abnormality at follow up (r = 0.15). Conclusions: Most patients had substantial perfusion abnormality at 3–6 months post PE. Abnormal perfusion patterns were frequently observed in patients and in regions with no corresponding evidence of residual thrombus on CTPA. Some defects exhibit delayed, presumed systemic, enhancement (which we have termed ‘stunned’ lung). CT perfusion provides combined anatomical and functional information about PE resolution.

  9. Comparing slow- versus high-speed CT for attenuation correction of cardiac SPECT perfusion studies.

    Science.gov (United States)

    Wells, R Glenn; Soueidan, Karen; Vanderwerf, Karen; Ruddy, Terrence D

    2012-08-01

    For SPECT, CT-based attenuation correction is preferred. Many different models of CT are available with SPECT/CT systems. Our study compares clinical cardiac SPECT images that were attenuation corrected using slow-rotation CT and high-speed CT transmission scans. We evaluated 59 rest/stress perfusion studies from patients who had undergone both a SPECT/CT with a slow-rotation CT and a perfusion study on a PET/CT camera equipped with a high-speed CT scanner. Each SPECT study was reconstructed with transmission maps from both CT scans and the relative perfusion was assessed using semi-automated software. The summed stress/rest/and difference scores (SSS/SRS/SDS) were compared as well as the test classification. The intraclass correlation coefficients for the SSS, SRS, and SDS were 0.97, 0.96, and 0.80 respectively. There were no significant differences in the mean SSS, SRS, or SDS with the use of either CT for attenuation corrections. Classifying SSS > 3 as abnormal, there was 97% concordance (κ = 0.88). Classifying SDS > 1 as abnormal, there was 95% concordance (κ = 0.54). A McNemar's test showed no significant differences. There were no significant differences between using a high-speed CT and using a slow-rotation CT for attenuation correction of SPECT myocardial perfusion images.

  10. Low-Dose Volume-Perfusion CT of the Brain: Effects of Radiation Dose Reduction on Performance of Perfusion CT Algorithms.

    Science.gov (United States)

    Othman, A E; Afat, S; Brockmann, C; Nikoubashman, O; Bier, G; Brockmann, M A; Nikolaou, K; Tai, J H; Yang, Z P; Kim, J H; Wiesmann, M

    2017-09-01

    We aimed to compare different computed tomography (CT) perfusion post-processing algorithms regarding image quality of perfusion maps from low-dose volume perfusion CT (VPCT) and their diagnostic performance regarding the detection of ischemic brain lesions. We included VPCT data of 21 patients with acute stroke (onset Perfusion maps (cerebral blood volume (CBV); cerebral blood flow (CBF) from original and low-dose datasets were generated using two different commercially available post-processing methods: deconvolution-based method (DC) and maximum slope algorithm (MS). The resulting DC and MS perfusion maps were compared regarding perfusion values, signal-to-noise ratio (SNR) as well as image quality and diagnostic accuracy as rated by two blinded neuroradiologists. Quantitative perfusion parameters highly correlated for both algorithms and both dose levels (r ≥ 0.613, p perfusion maps from simulated low-dose VPCT. However, MS produced CBF maps with significantly higher image quality and SNR than DC, indicating that MS might be more suitable for low-dose VPCT imaging.

  11. Wernicke's Encephalopathy Mimicking Acute Onset Stroke Diagnosed by CT Perfusion

    Directory of Open Access Journals (Sweden)

    Alok Bhan

    2014-01-01

    Full Text Available Background. Metabolic syndromes such as Wernicke’s encephalopathy may present with a sudden neurological deficit, thus mimicking acute onset stroke. Due to current emphasis on rapid admission and treatment of acute stroke patients, there is a significant risk that these stroke mimics may end up being treated with thrombolysis. Rigorous clinical and radiological skills are necessary to correctly identify such metabolic stroke mimics, in order to avoid doing any harm to these patients due to the unnecessary use of thrombolysis. Patient. A 51-year-old Caucasian male was admitted to our hospital with suspicion of an acute stroke due to sudden onset dysarthria and unilateral facial nerve paresis. Clinical examination revealed confusion and dysconjugate gaze. Computed tomography (CT including a CT perfusion (CTP scan revealed bilateral thalamic hyperperfusion. The use of both clinical and radiological findings led to correctly diagnosing Wernicke’s encephalopathy. Conclusion. The application of CTP as a standard diagnostic tool in acute stroke patients can improve the detection of stroke mimics caused by metabolic syndromes as shown in our case report.

  12. Myocardial perfusion studies in coronary diseases

    International Nuclear Information System (INIS)

    Mut, Fernando

    1994-01-01

    For detecting in precocious form a coronary disease is necessary to apply a diagnostic techniques. The main considerations to be indicated in the present work are: physiological considerations, myocardial perfusion studies with radiotracers such as Talio 201, 99mTc, MIBI, 99mTc-Teboroxima, 99mTc-Fosfinas, instrumentation for obtain good images,proceedings protocols, studies interpretation, standards, SPECT, anomalies standards, coronary diseases

  13. The value of whole-brain CT perfusion imaging and CT angiography using a 320-slice CT scanner in the diagnosis of MCI and AD patients.

    Science.gov (United States)

    Zhang, Bo; Gu, Guo-Jun; Jiang, Hong; Guo, Yi; Shen, Xing; Li, Bo; Zhang, Wei

    2017-11-01

    To validate the value of whole-brain computed tomography perfusion (CTP) and CT angiography (CTA) in the diagnosis of mild cognitive impairment (MCI) and Alzheimer's disease (AD). Whole-brain CTP and four-dimensional CT angiography (4D-CTA) images were acquired in 30 MCI, 35 mild AD patients, 35 moderate AD patients, 30 severe AD patients and 50 normal controls (NC). Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and correlation between CTP and 4D-CTA were analysed. Elevated CBF in the left frontal and temporal cortex was found in MCI compared with the NC group. However, TTP was increased in the left hippocampus in mild AD patients compared with NC. In moderate and severe AD patients, hypoperfusion was found in multiple brain areas compared with NC. Finally, we found that the extent of arterial stenosis was negatively correlated with CBF in partial cerebral cortex and hippocampus, and positively correlated with TTP in these areas of AD and MCI patients. Our findings suggest that whole-brain CTP and 4D-CTA could serve as a diagnostic modality in distinguishing MCI and AD, and predicting conversion from MCI based on TTP of left hippocampus. • Whole-brain perfusion using the full 160-mm width of 320 detector rows • Provide clinical experience of 320-row CT in cerebrovascular disorders of Alzheimer's disease • Initial combined 4D CTA-CTP data analysed perfusion and correlated with CT angiography • Whole-brain CTP and 4D-CTA have high value for monitoring MCI to AD progression • TTP in the left hippocampus may predict the transition from MCI to AD.

  14. Evaluation of hyperacute infarct volume using ASPECTS and brain CT perfusion core volume.

    Science.gov (United States)

    Demeestere, Jelle; Garcia-Esperon, Carlos; Garcia-Bermejo, Pablo; Ombelet, Fouke; McElduff, Patrick; Bivard, Andrew; Parsons, Mark; Levi, Christopher

    2017-06-13

    To compare the accuracy of Alberta Stroke Program Early Computed Tomography Score (ASPECTS) and CT perfusion to detect established infarction in acute anterior circulation stroke. We performed an observational study in 59 acute anterior circulation ischemic stroke patients who underwent brain noncontrast CT, CT perfusion, and MRI within 100 minutes from CT imaging. ASPECTS scores were calculated by 4 blinded vascular neurologists. The accuracy of ASPECTS and CT perfusion core volume to detect an acute MRI diffusion lesion of ≥70 mL was evaluated using receiver operating characteristics analysis and optimum cutoff values were calculated using Youden J. Median ASPECTS score was 8 (interquartile range [IQR] 5-9). Median CT perfusion core volume was 22 mL (IQR 10.4-71.9). Median MRI diffusion lesion volume was 24.5 mL (IQR 10-63.9). No significant difference was found between the accuracy of CT perfusion and ASPECTS ( c statistic 0.95 vs 0.87, p value for difference = 0.17). The optimum ASPECTS cutoff score to detect a diffusion-weighted imaging lesion ≥70 mL was CT perfusion core volume cutoff was ≥50 mL (sensitivity 0.86, specificity 0.97, Youden J = 0.84). The CT perfusion core lesion covered a median of 100% (IQR 86%-100%) of the acute MRI lesion volume (Pearson R = 0.88; R 2 = 0.77). We found no significant difference between the accuracy of CT perfusion and ASPECTS to predict hyperacute MRI lesion volume in ischemic stroke. Copyright © 2017 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.

  15. Correlation of iodine uptake and perfusion parameters between dual-energy CT imaging and first-pass dual-input perfusion CT in lung cancer.

    Science.gov (United States)

    Chen, Xiaoliang; Xu, Yanyan; Duan, Jianghui; Li, Chuandong; Sun, Hongliang; Wang, Wu

    2017-07-01

    To investigate the potential relationship between perfusion parameters from first-pass dual-input perfusion computed tomography (DI-PCT) and iodine uptake levels estimated from dual-energy CT (DE-CT).The pre-experimental part of this study included a dynamic DE-CT protocol in 15 patients to evaluate peak arterial enhancement of lung cancer based on time-attenuation curves, and the scan time of DE-CT was determined. In the prospective part of the study, 28 lung cancer patients underwent whole-volume perfusion CT and single-source DE-CT using 320-row CT. Pulmonary flow (PF, mL/min/100 mL), aortic flow (AF, mL/min/100 mL), and a perfusion index (PI = PF/[PF + AF]) were automatically generated by in-house commercial software using the dual-input maximum slope method for DI-PCT. For the dual-energy CT data, iodine uptake was estimated by the difference (λ) and the slope (λHU). λ was defined as the difference of CT values between 40 and 70 KeV monochromatic images in lung lesions. λHU was calculated by the following equation: λHU = |λ/(70 - 40)|. The DI-PCT and DE-CT parameters were analyzed by Pearson/Spearman correlation analysis, respectively.All subjects were pathologically proved as lung cancer patients (including 16 squamous cell carcinoma, 8 adenocarcinoma, and 4 small cell lung cancer) by surgery or CT-guided biopsy. Interobserver reproducibility in DI-PCT (PF, AF, PI) and DE-CT (λ, λHU) were relatively good to excellent (intraclass correlation coefficient [ICC]Inter = 0.8726-0.9255, ICCInter = 0.8179-0.8842; ICCInter = 0.8881-0.9177, ICCInter = 0.9820-0.9970, ICCInter = 0.9780-0.9971, respectively). Correlation coefficient between λ and AF, and PF were as follows: 0.589 (P input CT perfusion analysis method can be applied to assess blood supply of lung cancer patients. Preliminary results demonstrated that the iodine uptake relevant parameters derived from DE-CT significantly correlated with perfusion

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

  17. Incremental Diagnostic Value of Stress Computed Tomography Myocardial Perfusion With Whole-Heart Coverage CT Scanner in Intermediate- to High-Risk Symptomatic Patients Suspected of Coronary Artery Disease.

    Science.gov (United States)

    Pontone, Gianluca; Andreini, Daniele; Guaricci, Andrea I; Baggiano, Andrea; Fazzari, Fabio; Guglielmo, Marco; Muscogiuri, Giuseppe; Berzovini, Claudio Maria; Pasquini, Annalisa; Mushtaq, Saima; Conte, Edoardo; Calligaris, Giuseppe; De Martini, Stefano; Ferrari, Cristina; Galli, Stefano; Grancini, Luca; Ravagnani, Paolo; Teruzzi, Giovanni; Trabattoni, Daniela; Fabbiocchi, Franco; Lualdi, Alessandro; Montorsi, Piero; Rabbat, Mark G; Bartorelli, Antonio L; Pepi, Mauro

    2018-02-09

    The goal of this study was to evaluate the diagnostic accuracy of stress computed tomography myocardial perfusion (CTP) for the detection of functionally significant coronary artery disease (CAD) by using invasive coronary angiography (ICA) plus invasive fractional flow reserve (FFR) as the reference standard in consecutive intermediate- to high-risk symptomatic patients. Stress CTP recently emerged as a potential strategy to combine the anatomic and functional evaluation of CAD in a single scan. A total of 100 consecutive symptomatic patients scheduled for ICA were prospectively enrolled. All patients underwent rest coronary computed tomography angiography (CTA) followed by stress static CTP with a whole-heart coverage CT scanner (Revolution CT, GE Healthcare, Milwaukee, Wisconsin). Diagnostic accuracy and overall effective dose were assessed and compared versus those of ICA and invasive FFR. The prevalence of obstructive CAD and functionally significant CAD were 69% and 44%, respectively. Coronary CTA alone demonstrated a per-vessel and per-patient sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of 98%, 76%, 99%, 63%, and 83% and of 98%, 54%, 96%, 68%, and 76%, respectively. Combining coronary CTA with stress CTP, per-vessel and per-patient sensitivity, specificity, negative predictive value, positive predictive value, and accuracy were 91%, 94%, 96%, 86%, and 93% and 98%, 83%, 98%, 86%, and 91%, with a significant improvement in specificity, positive predictive value, and accuracy in both models. The mean effective dose for coronary CTA and stress CTP were 2.8 ± 1.4 mSv and 2.5 ± 1.1 mSv. The inclusion of stress CTP for the evaluation of patients with an intermediate to high risk for CAD is feasible and improved the diagnostic performance of coronary CTA for detecting functionally significant CAD. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  18. A Simplified Whole-Organ CT Perfusion Technique with Biphasic Acquisition: Preliminary Investigation of Accuracy and Protocol Feasibility in Kidneys.

    Science.gov (United States)

    Yuan, XiaoDong; Zhang, Jing; Quan, ChangBin; Tian, Yuan; Li, Hong; Ao, GuoKun

    2016-04-01

    To determine the feasibility and accuracy of a protocol for calculating whole-organ renal perfusion (renal blood flow [RBF]) and regional perfusion on the basis of biphasic computed tomography (CT), with concurrent dynamic contrast material-enhanced (DCE) CT perfusion serving as the reference standard. This prospective study was approved by the institutional review board, and written informed consent was obtained from all patients. Biphasic CT of the kidneys, including precontrast and arterial phase imaging, was integrated with a first-pass dynamic volume CT protocol and performed and analyzed in 23 patients suspected of having renal artery stenosis. The perfusion value derived from biphasic CT was calculated as CT number enhancement divided by the area under the arterial input function and compared with the DCE CT perfusion data by using the paired t test, correlation analysis, and Bland-Altman plots. Correlation analysis was made between the RBF and the extent of renal artery stenosis. All postprocessing was independently performed by two observers and then averaged as the final result. Mean ± standard deviation biphasic and DCE CT perfusion data for RBF were 425.62 mL/min ± 124.74 and 419.81 mL/min ± 121.13, respectively (P = .53), and for regional perfusion they were 271.15 mL/min per 100 mL ± 82.21 and 266.33 mL/min per 100 mL ± 74.40, respectively (P = .31). Good correlation and agreement were shown between biphasic and DCE CT perfusion for RBF (r = 0.93; ±10% variation from mean perfusion data [P perfusion (r = 0.90; ±13% variation from mean perfusion data [P CT perfusion (r = -0.81, P = .012). Biphasic CT perfusion is clinically feasible and provides perfusion data comparable to DCE CT perfusion data at both global and regional levels in the kidney. Online supplemental material is available for this article.

  19. Myocardial ischemia detection with single-phase CT perfusion in symptomatic patients using high-pitch helical image acquisition technique.

    Science.gov (United States)

    Bischoff, Bernhard; Deseive, Simon; Rampp, Martin; Todica, Andrei; Wermke, Marc; Martinoff, Stefan; Massberg, Steffen; Reiser, Maximilian F; Becker, Hans-Christoph; Hausleiter, Jörg

    2017-04-01

    Coronary CT angiography (CCTA) suffers from a reduced diagnostic accuracy in patients with heavily calcified coronary arteries or prior myocardial revascularisation due to artefacts caused by calcifications and stent material. CT myocardial perfusion imaging (CTMPI) yields high potential for the detection of myocardial ischemia and might help to overcome the above mentioned limitations. We analysed CT single-phase perfusion using high-pitch helical image acquisition technique in patients with prior myocardial revascularisation. Thirty-six patients with an indication for invasive coronary angiography (28 with coronary stents, 2 with coronary artery bypass grafts and 6 with both) were included in this prospective study at two study sites. All patients were examined on a 2nd generation dual-source CT system. Stress CT images were obtained using a prospectively ECG-triggered single-phase high-pitch helical image acquisition technique. During stress the tracer for myocardial perfusion (MP) SPECT imaging was administered. Rest CT images were acquired using prospectively ECG-triggered sequential CT. MP-SPECT imaging and invasive coronary angiography served as standard of reference. In this heavily diseased patient cohort CCTA alone showed a low overall diagnostic accuracy for detection of hemodynamically relevant coronary artery stenosis of only 31% on a per-patient base and 60% on a per-vessel base. Combining CCTA and CTMPI allowed for a significantly higher overall diagnostic accuracy of 78% on a per-patient base and 92% on a per-vessel base (p CT scans was 0.9 mSv, mean radiation dose for rest CT scans was 5.0 mSv. In symptomatic patients with known coronary artery disease and prior myocardial revascularization combining CCTA and CTMPI showed significantly higher diagnostic accuracy in detection of hemodynamically significant coronary artery stenosis when compared to CCTA alone.

  20. Timing-Invariant CT Angiography Derived from CT Perfusion Imaging in Acute Stroke : A Diagnostic Performance Study

    NARCIS (Netherlands)

    Smith, E. J.; Vonken, E. -J.; Meijer, F. J. A.; Dankbaar, J. W.; Horsch, A. D.; van Ginneken, B.; Velthuis, B.; van der Schaaf, I.; Prokop, M.

    2015-01-01

    BACKGROUND AND PURPOSE: Timing-invariant (or delay-insensitive) CT angiography derived from CT perfusion data may obviate a separate cranial CTA in acute stroke, thus enhancing patient safety by reducing total examination time, radiation dose, and volume of contrast material. We assessed the

  1. Local cortical hypoperfusion imaged with CT perfusion during postictal Todd's paresis

    Energy Technology Data Exchange (ETDEWEB)

    Mathews, Marlon S.; Binder, Devin K. [University of California, Department of Neurological Surgery, Irvine, CA (United States); Smith, Wade S. [University of California, Department of Neurology, San Francisco, CA (United States); Wintermark, Max; Dillon, William P. [University of California, Department of Radiology, San Francisco, CA (United States)

    2008-05-15

    Postictal ('Todd's') paralysis, or 'epileptic hemiplegia,' is a well-known complication of focal or generalized epileptic seizures. However, it is unclear whether the pathophysiology of Todd's paralysis is related to alterations in cerebral perfusion. We report CT perfusion findings in a patient presenting with postictal aphasia and right hemiparesis. A 62-year-old woman with a history of alcohol abuse, closed head injury and posttraumatic epilepsy, presented with acute onset aphasia and right hemiparesis. A non-contrast head CT scan demonstrated no acute hemorrhage. Left hemispheric ischemia was suspected, and the patient was considered for acute thrombolytic therapy. MRI revealed a subtle increase in signal intensity involving the left medial temporal, hippocampal and parahippocampal regions on both T2-weighted FLAIR and diffusion-weighted sequences. CT angiography and CT perfusion study were performed. The CT perfusion study and CT angiography demonstrated a dramatic reduction in cerebral blood flow and blood volume involving the entire left hemisphere, but with relative symmetry of mean transit time, ruling out a large vessel occlusion. Clinical resolution of the aphasia and hemiparesis occurred within a few hours, and correlated with normalization of perfusion to the left hemisphere (detected by MR perfusion). This unique case is the first in which clinical evidence of Todd's paralysis has been correlated with reversible postictal hemispheric changes on CT and MR perfusion studies. This is important because CT perfusion study is being used more and more in the diagnosis of acute stroke, and one needs to be careful to not misinterpret the data. (orig.)

  2. Local cortical hypoperfusion imaged with CT perfusion during postictal Todd's paresis

    International Nuclear Information System (INIS)

    Mathews, Marlon S.; Binder, Devin K.; Smith, Wade S.; Wintermark, Max; Dillon, William P.

    2008-01-01

    Postictal (''Todd's'') paralysis, or ''epileptic hemiplegia,'' is a well-known complication of focal or generalized epileptic seizures. However, it is unclear whether the pathophysiology of Todd's paralysis is related to alterations in cerebral perfusion. We report CT perfusion findings in a patient presenting with postictal aphasia and right hemiparesis. A 62-year-old woman with a history of alcohol abuse, closed head injury and posttraumatic epilepsy, presented with acute onset aphasia and right hemiparesis. A non-contrast head CT scan demonstrated no acute hemorrhage. Left hemispheric ischemia was suspected, and the patient was considered for acute thrombolytic therapy. MRI revealed a subtle increase in signal intensity involving the left medial temporal, hippocampal and parahippocampal regions on both T2-weighted FLAIR and diffusion-weighted sequences. CT angiography and CT perfusion study were performed. The CT perfusion study and CT angiography demonstrated a dramatic reduction in cerebral blood flow and blood volume involving the entire left hemisphere, but with relative symmetry of mean transit time, ruling out a large vessel occlusion. Clinical resolution of the aphasia and hemiparesis occurred within a few hours, and correlated with normalization of perfusion to the left hemisphere (detected by MR perfusion). This unique case is the first in which clinical evidence of Todd's paralysis has been correlated with reversible postictal hemispheric changes on CT and MR perfusion studies. This is important because CT perfusion study is being used more and more in the diagnosis of acute stroke, and one needs to be careful to not misinterpret the data. (orig.)

  3. Pulmonary vascular volume ratio measured by cardiac computed tomography in children and young adults with congenital heart disease: comparison with lung perfusion scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo; Park, Sang Hyub [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of)

    2017-11-15

    Lung perfusion scintigraphy is regarded as the gold standard for evaluating differential lung perfusion ratio in congenital heart disease. To compare cardiac CT with lung perfusion scintigraphy for estimated pulmonary vascular volume ratio in patients with congenital heart disease. We included 52 children and young adults (median age 4 years, range 2 months to 28 years; 31 males) with congenital heart disease who underwent cardiac CT and lung perfusion scintigraphy without an interim surgical or transcatheter intervention and within 1 year. We calculated the right and left pulmonary vascular volumes using threshold-based CT volumetry. Then we compared right pulmonary vascular volume percentages at cardiac CT with right lung perfusion percentages at lung perfusion scintigraphy by using paired t-test and Bland-Altman analysis. The right pulmonary vascular volume percentages at cardiac CT (66.3 ± 14.0%) were significantly smaller than the right lung perfusion percentages at lung perfusion scintigraphy (69.1 ± 15.0%; P=0.001). Bland-Altman analysis showed a mean difference of -2.8 ± 5.8% and 95% limits of agreement (-14.1%, 8.5%) between these two variables. Cardiac CT, in a single examination, can offer pulmonary vascular volume ratio in addition to pulmonary artery anatomy essential for evaluating peripheral pulmonary artery stenosis in patients with congenital heart disease. However there is a wide range of agreement between cardiac CT and lung perfusion scintigraphy. (orig.)

  4. Whole-Organ CT Perfusion of the Pancreas: Impact of Iterative Reconstruction on Image Quality, Perfusion Parameters and Radiation Dose in 256-Slice CT-Preliminary Findings

    Science.gov (United States)

    Xie, Qian; Wu, Juan; Tang, Ying; Dou, Yafang; Hao, Sijie; Xu, Feijia; Feng, Xiaoyuan; Liang, Zonghui

    2013-01-01

    Background This study was performed to assess whether iterative reconstruction can reduce radiation dose while maintaining acceptable image quality, and to investigate whether perfusion parameters vary from conventional filtered back projection (FBP) at the low-tube-voltage (80-kVp) during whole-pancreas perfusion examination using a 256-slice CT. Methods 76 patients with known or suspected pancreatic mass underwent whole-pancreas perfusion by a 256-slice CT. High- and low-tube-voltage CT images were acquired. 120-kVp image data (protocol A) and 80-kVp image data (protocol B) were reconstructed with conventional FBP, and 80-kVp image data were reconstructed with iDose4 (protocol C) iterative reconstruction. The image noise; contrast-to-noise ratio (CNR) relative to muscle for the pancreas, liver, and aorta; and radiation dose of each protocol were assessed quantitatively. Overall image quality was assessed qualitatively. Among 76 patients, 23 were eventually proven to have a normal pancreas. Perfusion parameters of normal pancreas in each protocol including blood volume, blood flow, and permeability-surface area product were measured. Results In the quantitative study, protocol C reduced image noise by 36.8% compared to protocol B (Pperfusion values among three different protocols. Conclusion Low-tube-voltage and iDose4 iterative reconstruction can dramatically decrease the radiation dose with acceptable image quality during whole-pancreas CT perfusion and have no significant impact on the perfusion parameters of normal pancreas compared to the conventional FBP reconstruction using a 256-slice CT scanner. PMID:24303017

  5. Prognostic Value of Combined CT Angiography and Myocardial Perfusion Imaging versus Invasive Coronary Angiography and Nuclear Stress Perfusion Imaging in the Prediction of Major Adverse Cardiovascular Events: The CORE320 Multicenter Study.

    Science.gov (United States)

    Chen, Marcus Y; Rochitte, Carlos E; Arbab-Zadeh, Armin; Dewey, Marc; George, Richard T; Miller, Julie M; Niinuma, Hiroyuki; Yoshioka, Kunihiro; Kitagawa, Kakuya; Sakuma, Hajime; Laham, Roger; Vavere, Andrea L; Cerci, Rodrigo J; Mehra, Vishal C; Nomura, Cesar; Kofoed, Klaus F; Jinzaki, Masahiro; Kuribayashi, Sachio; Scholte, Arthur J; Laule, Michael; Tan, Swee Yaw; Hoe, John; Paul, Narinder; Rybicki, Frank J; Brinker, Jeffrey A; Arai, Andrew E; Matheson, Matthew B; Cox, Christopher; Clouse, Melvin E; Di Carli, Marcelo F; Lima, João A C

    2017-07-01

    Purpose To compare the prognostic importance (time to major adverse cardiovascular event [MACE]) of combined computed tomography (CT) angiography and CT myocardial stress perfusion imaging with that of combined invasive coronary angiography (ICA) and stress single photon emission CT myocardial perfusion imaging. Materials and Methods This study was approved by all institutional review boards, and written informed consent was obtained. Between November 2009 and July 2011, 381 participants clinically referred for ICA and aged 45-85 years were enrolled in the Combined Noninvasive Coronary Angiography and Myocardial Perfusion Imaging Using 320-Detector Row Computed Tomography (CORE320) prospective multicenter diagnostic study. All images were analyzed in blinded independent core laboratories, and a panel of physicians adjudicated all adverse events. MACE was defined as revascularization (>30 days after index ICA), myocardial infarction, or cardiac death; hospitalization for chest pain or congestive heart failure; or arrhythmia. Late MACE was defined similarly, except for patients who underwent revascularization within the first 182 days after ICA, who were excluded. Comparisons of 2-year survival (time to MACE) used standard Kaplan-Meier curves and restricted mean survival times bootstrapped with 2000 replicates. Results An MACE (49 revascularizations, five myocardial infarctions, one cardiac death, nine hospitalizations for chest pain or congestive heart failure, and one arrhythmia) occurred in 51 of 379 patients (13.5%). The 2-year MACE-free rates for combined CT angiography and CT perfusion findings were 94% negative for coronary artery disease (CAD) versus 82% positive for CAD and were similar to combined ICA and single photon emission CT findings (93% negative for CAD vs 77% positive for CAD, P CT angiography and CT perfusion versus ICA and single photon emission CT for either positive or negative results were not significantly different for MACE or late MACE (P

  6. Diagnostic accuracy of lung subtraction iodine mapping CT for the evaluation of pulmonary perfusion in patients with chronic thromboembolic pulmonary hypertension: Correlation with perfusion SPECT/CT.

    Science.gov (United States)

    Tamura, Masashi; Yamada, Yoshitake; Kawakami, Takashi; Kataoka, Masaharu; Iwabuchi, Yu; Sugiura, Hiroaki; Hashimoto, Masahiro; Nakahara, Tadaki; Okuda, Shigeo; Nakatsuka, Seishi; Sano, Fumiya; Abe, Takayuki; Maekawa, Yuichiro; Fukuda, Keiichi; Jinzaki, Masahiro

    2017-09-15

    For treatment of chronic thromboembolic pulmonary hypertension (CTEPH), the evaluation of segmental pulmonary perfusion is important. There are no previous reports about lung subtraction iodine mapping (LSIM) computed tomography (CT) for evaluation of segmental pulmonary perfusion in patients with CTEPH, using lung perfusion SPECT/CT (LPS) as the reference. 50 patients (age, 60.7±16.7years) with known or suspected CTEPH were enrolled in this study. Non-contrast chest CT and CT pulmonary angiography (CTPA) were performed on a 320-detector row CT system. Then, based on a non-rigid registration followed by subtraction of non-contrast images from contrast-enhanced images, color-coded LSIM images were generated. LPS was performed using a SPECT/CT system within a period of 2months, and served as the reference standard. LSIM and CTPA images were evaluated in a blinded manner for the detection of pulmonary perfusion defects on a segment-by-segment basis. The sensitivity, specificity, accuracy, and positive and negative predictive values of LSIM for the detection of segmental perfusion defects were 95% (734/773), 84% (107/127), 93% (841/900), 97% (734/754) and 73% (107/146), respectively, while the corresponding values for CTPA were 65% (505/773), 61% (78/127), 65% (583/900), 91% (505/554) and 23% (78/346). Generalized estimating equations analyses revealed a significantly better performance of LSIM than that of CTPA regarding the sensitivity, accuracy, and positive and negative predictive values (all Pperfusion in patients with CTEPH, and it provides a significantly higher diagnostic accuracy compared with CTPA. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Stroke prognosis by applying double thresholds on CT-perfusion-brain images

    Science.gov (United States)

    Chokchaitam, Somchart; Santipromwong, Nittaya; Muengtaweepongsa, Sombat

    2013-03-01

    The CT-perfusion image shows information of brain abnormalities such as its size and location. Generally, neurologist diagnoses stroke disease using CT-perfusion images such as Cerebral blood flow (CBF), cerebral blood volume (CBV). In our previous report, we applied threshold technique to divide amount of CBV and CBF into low and high level. Then, their levels are applied to identify normal tissue areas, dead tissue areas (infract core) and blood-cot tissue areas (infract penumbra). However, it's not totally correct, if the same threshold is applied to the whole area (it must depend on size of blood vessel in that area. In this report, we propose double thresholds to divided CBV and CBF into 3 levels: very low, medium and very high levels. Very low and very high levels are definitely implied to bad areas and good areas, respectively. The proposed double thresholds makes stroke prognosis more accurate. The simulation results confirm that our proposed results closed to results defined from neurologist comparing to the conventional results.

  8. Differentiation of malignant and benign pulmonary nodules with first-pass dual-input perfusion CT.

    Science.gov (United States)

    Yuan, Xiaodong; Zhang, Jing; Quan, Changbin; Cao, Jianxia; Ao, Guokun; Tian, Yuan; Li, Hong

    2013-09-01

    To assess diagnostic performance of dual-input CT perfusion for distinguishing malignant from benign solitary pulmonary nodules (SPNs). Fifty-six consecutive subjects with SPNs underwent contrast-enhanced 320-row multidetector dynamic volume CT. The dual-input maximum slope CT perfusion analysis was employed to calculate the pulmonary flow (PF), bronchial flow (BF), and perfusion index [Formula: see text]. Differences in perfusion parameters between malignant and benign tumours were assessed with histopathological diagnosis as the gold standard. Diagnostic value of the perfusion parameters was calculated using the receiver-operating characteristic (ROC) curve analysis. Amongst 56 SPNs, statistically significant differences in all three perfusion parameters were revealed between malignant and benign tumours. The PI demonstrated the biggest difference between malignancy and benignancy: 0.30 ± 0.07 vs. 0.51 ± 0.13 , P perfusion parameters, producing a sensitivity of 0.95, specificity of 0.83, positive likelihood ratio (+LR) of 5.59, and negative likelihood ratio (-LR) of 0.06 in identifying malignancy. The PI derived from the dual-input maximum slope CT perfusion analysis is a valuable biomarker for identifying malignancy in SPNs. PI may be potentially useful for lung cancer treatment planning and forecasting the therapeutic effect of radiotherapy treatment. • Modern CT equipment offers assessment of vascular parameters of solitary pulmonary nodules (SPNs) • Dual vascular supply was investigated to differentiate malignant from benign SPNs. • Different dual vascular supply patterns were found in malignant and benign SPNs. • The perfusion index is a useful biomarker for differentiate malignancy from benignancy.

  9. CT angiography and CT perfusion improve prediction of infarct volume in patients with anterior circulation stroke

    Energy Technology Data Exchange (ETDEWEB)

    Seeters, Tom van; Schaaf, Irene C. van der; Dankbaar, Jan Willem; Horsch, Alexander D.; Niesten, Joris M.; Luitse, Merel J.A.; Mali, Willem P.T.M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Biessels, Geert Jan; Kappelle, L.J. [University Medical Center Utrecht, Department of Neurology, Brain Center Rudolf Magnus, Utrecht (Netherlands); Majoie, Charles B.L.M. [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Vos, Jan Albert [St. Antonius Hospital, Department of Radiology, Nieuwegein (Netherlands); Schonewille, Wouter J. [St. Antonius Hospital, Department of Neurology, Nieuwegein (Netherlands); Walderveen, Marianne A.A. van [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Wermer, Marieke J.H. [Leiden University Medical Center, Department of Neurology, Leiden (Netherlands); Duijm, Lucien E.M. [Catharina Hospital, Department of Radiology, Eindhoven (Netherlands); Keizer, Koos [Catharina Hospital, Department of Neurology, Eindhoven (Netherlands); Bot, Joseph C.J. [VU University Medical Center, Department of Radiology, Amsterdam (Netherlands); Visser, Marieke C. [VU University Medical Center, Department of Neurology, Amsterdam (Netherlands); Lugt, Aad van der [Erasmus MC University Medical Center, Department of Radiology, Rotterdam (Netherlands); Dippel, Diederik W.J. [Erasmus MC University Medical Center, Department of Neurology, Rotterdam (Netherlands); Kesselring, F.O.H.W. [Rijnstate Hospital, Department of Radiology, Arnhem (Netherlands); Hofmeijer, Jeannette [Rijnstate Hospital, Department of Neurology, Arnhem (Netherlands); Lycklama a Nijeholt, Geert J. [Medical Center Haaglanden, Department of Radiology, The Hague (Netherlands); Boiten, Jelis [Medical Center Haaglanden, Department of Neurology, The Hague (Netherlands); Rooij, Willem Jan van [St. Elisabeth Hospital, Department of Radiology, Tilburg (Netherlands); Kort, Paul L.M. de [St. Elisabeth Hospital, Department of Neurology, Tilburg (Netherlands); Roos, Yvo B.W.E.M. [Academic Medical Center, Department of Neurology, Amsterdam (Netherlands); Meijer, Frederick J.A. [Radboud University Medical Center, Department of Radiology, Nijmegen (Netherlands); Pleiter, C.C. [St. Franciscus Hospital, Department of Radiology, Rotterdam (Netherlands); Graaf, Yolanda van der [University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); Collaboration: Dutch acute stroke study (DUST) investigators

    2016-04-15

    We investigated whether baseline CT angiography (CTA) and CT perfusion (CTP) in acute ischemic stroke could improve prediction of infarct presence and infarct volume on follow-up imaging. We analyzed 906 patients with suspected anterior circulation stroke from the prospective multicenter Dutch acute stroke study (DUST). All patients underwent baseline non-contrast CT, CTA, and CTP and follow-up non-contrast CT/MRI after 3 days. Multivariable regression models were developed including patient characteristics and non-contrast CT, and subsequently, CTA and CTP measures were added. The increase in area under the curve (AUC) and R{sup 2} was assessed to determine the additional value of CTA and CTP. At follow-up, 612 patients (67.5 %) had a detectable infarct on CT/MRI; median infarct volume was 14.8 mL (interquartile range (IQR) 2.8-69.6). Regarding infarct presence, the AUC of 0.82 (95 % confidence interval (CI) 0.79-0.85) for patient characteristics and non-contrast CT was improved with addition of CTA measures (AUC 0.85 (95 % CI 0.82-0.87); p < 0.001) and was even higher after addition of CTP measures (AUC 0.89 (95 % CI 0.87-0.91); p < 0.001) and combined CTA/CTP measures (AUC 0.89 (95 % CI 0.87-0.91); p < 0.001). For infarct volume, adding combined CTA/CTP measures (R{sup 2} = 0.58) was superior to patient characteristics and non-contrast CT alone (R{sup 2} = 0.44) and to addition of CTA alone (R{sup 2} = 0.55) or CTP alone (R{sup 2} = 0.54; all p < 0.001). In the acute stage, CTA and CTP have additional value over patient characteristics and non-contrast CT for predicting infarct presence and infarct volume on follow-up imaging. These findings could be applied for patient selection in future trials on ischemic stroke treatment. (orig.)

  10. The role of volume perfusion CT in the diagnosis of pathologies of the pancreas; Die Rolle des Volumenperfusions-CT in der Diagnostik von Pankreaspathologika

    Energy Technology Data Exchange (ETDEWEB)

    Groezinger, G.; Groezinger, A.; Horger, M. [Universitaetsklinik Tuebingen (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie

    2014-12-15

    The review discusses the potential role of volume perfusion CT (VPCT) in the diagnosis and follow-up of different pathologies of the pancreas. VPCT enables a differentiation of different pancreatic tumors like adenocarcinoma or neuroendocrine tumors based on functional parameters like blood flow, blood volume and permeability. Furthermore, the article discusses the potential indications for VPCT imaging of inflammatory diseases of the pancreas such as acute or chronic pancreatitis and autoimmune pancreatitis.

  11. CT perfusion imaging in response assessment of pulmonary metastases undergoing stereotactic ablative radiotherapy.

    Science.gov (United States)

    Sawyer, Brooke; Pun, Emma; Samuel, Michael; Tay, Huilee; Kron, Tomas; Bressel, Mathias; Ball, David; Siva, Shankar

    2015-04-01

    Stereotactic ablative body radiotherapy (SABR) is an emerging treatment technique for pulmonary metastases in which conventional Response Evaluation Criteria in Solid Tumours (RECIST) may be inadequate. This study aims to assess the utility of CT perfusion imaging in response assessment of pulmonary metastases after SABR. In this ethics board-approved prospective study, 11 patients underwent a 26-Gy single fraction of SABR to pulmonary metastases. CT perfusion imaging occurred prior to and at 14 and 70 days post-SABR. Blood flow (mL/100 mL/min), blood volume (mL/100 mL), time to peak (seconds) and surface permeability (mL/100 mL/min), perfusion parameters of pulmonary metastases undergoing SABR, were independently assessed by two radiologists. Inter-observer variability was analysed. CT perfusion results were analysed for early response assessment comparing day 14 with baseline scans and for late response by comparing day 70 with baseline scans. The largest diameter of the pulmonary metastases undergoing SABR was recorded. Ten patients completed all three scans and one patient had baseline and early response assessment CT perfusion scans only. There was strong level of inter-observer agreement of CT perfusion interpretation with a median intraclass coefficient of 0.87 (range 0.20-0.98). Changes in all four perfusion parameters and tumour sizes were not statistically significant. CT perfusion imaging of pulmonary metastases is a highly reproducible imaging technique that may provide additional response assessment information above that of conventional RECIST, and it warrants further study in a larger cohort of patients undergoing SABR. © 2015 The Royal Australian and New Zealand College of Radiologists.

  12. CT perfusion imaging in response assessment of pulmonary metastases undergoing stereotactic ablative radiotherapy

    International Nuclear Information System (INIS)

    Sawyer, Brooke; Pun, Emma; Tay, Huilee; Kron, Tomas; Bressel, Mathias; Ball, David; Siva, Shankar; Samuel, Michael

    2015-01-01

    Stereotactic ablative body radiotherapy (SABR) is an emerging treatment technique for pulmonary metastases in which conventional Response Evaluation Criteria in Solid Tumours (RECIST) may be inadequate. This study aims to assess the utility of CT perfusion imaging in response assessment of pulmonary metastases after SABR. In this ethics board-approved prospective study, 11 patients underwent a 26-Gy single fraction of SABR to pulmonary metastases. CT perfusion imaging occurred prior to and at 14 and 70 days post-SABR. Blood flow (mL/100 mL/min), blood volume (mL/100 mL), time to peak (seconds) and surface permeability (mL/100 mL/min), perfusion parameters of pulmonary metastases undergoing SABR, were independently assessed by two radiologists. Inter-observer variability was analysed. CT perfusion results were analysed for early response assessment comparing day 14 with baseline scans and for late response by comparing day 70 with baseline scans. The largest diameter of the pulmonary metastases undergoing SABR was recorded. Ten patients completed all three scans and one patient had baseline and early response assessment CT perfusion scans only. There was strong level of inter-observer agreement of CT perfusion interpretation with a median intraclass coefficient of 0.87 (range 0.20–0.98). Changes in all four perfusion parameters and tumour sizes were not statistically significant. CT perfusion imaging of pulmonary metastases is a highly reproducible imaging technique that may provide additional response assessment information above that of conventional RECIST, and it warrants further study in a larger cohort of patients undergoing SABR.

  13. SU-E-I-36: A KWIC and Dirty Look at Dose Savings and Perfusion Metrics in Simulated CT Neuro Perfusion Exams

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, J; Martin, T; Young, S; McNitt-Gray, M; Wang, D [UCLA School of Medicine, Los Angeles, CA (United States)

    2015-06-15

    Purpose: CT neuro perfusion scans are one of the highest dose exams. Methods to reduce dose include decreasing the number of projections acquired per gantry rotation, however conventional reconstruction of such scans leads to sampling artifacts. In this study we investigated a projection view-sharing reconstruction algorithm used in dynamic MRI – “K-space Weighted Image Contrast” (KWIC) – applied to simulated perfusion exams and evaluated dose savings and impacts on perfusion metrics. Methods: A FORBILD head phantom containing simulated time-varying objects was developed and a set of parallel-beam CT projection data was created. The simulated scans were 60 seconds long, 1152 projections per turn, with a rotation time of one second. No noise was simulated. 5mm, 10mm, and 50mm objects were modeled in the brain. A baseline, “full dose” simulation used all projections and reduced dose cases were simulated by downsampling the number of projections per turn from 1152 to 576 (50% dose), 288 (25% dose), and 144 (12.5% dose). KWIC was further evaluated at 72 projections per rotation (6.25%). One image per second was reconstructed using filtered backprojection (FBP) and KWIC. KWIC reconstructions utilized view cores of 36, 72, 144, and 288 views and 16, 8, 4, and 2 subapertures respectively. From the reconstructed images, time-to-peak (TTP), cerebral blood flow (CBF) and the FWHM of the perfusion curve were calculated and compared against reference values from the full-dose FBP data. Results: TTP, CBF, and the FWHM were unaffected by dose reduction (to 12.5%) and reconstruction method, however image quality was improved when using KWIC. Conclusion: This pilot study suggests that KWIC preserves image quality and perfusion metrics when under-sampling projections and that the unique contrast weighting of KWIC could provided substantial dose-savings for perfusion CT scans. Evaluation of KWIC in clinical CT data will be performed in the near future. R01 EB014922, NCI

  14. Low dose CT perfusion in acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Amanda; Symons, Sean; Jakubovic, Raphael; Zhang, Liying; Aviv, Richard I. [Sunnybrook Health Sciences Centre, Toronto, ON (Canada); So, Aaron; Lee, Ting-Yim [Robarts Research Institute, London, Ontario (Canada)

    2014-12-15

    The purpose of this investigation is to determine if CT perfusion (CTP) measurements at low doses (LD = 20 or 50 mAs) are similar to those obtained at regular doses (RD = 100 mAs), with and without the addition of adaptive statistical iterative reconstruction (ASIR). A single-center, prospective study was performed in patients with acute ischemic stroke (n = 37; 54 % male; age = 74 ± 15 years). Two CTP scans were performed on each subject: one at 100 mAs (RD) and one at either 50 or 20 mAs (LD). CTP parameters were compared between the RD and LD scans in regions of ischemia, infarction, and normal tissue. Differences were determined using a within-subjects ANOVA (p < 0.05) followed by a paired t test post hoc analysis (p < 0.01). At 50 mAs, there was no significant difference between cerebral blood flow (CBF), cerebral blood volume (CBV), or time to maximum enhancement (Tmax) values for the RD and LD scans in the ischemic, infarcted, or normal contralateral regions (p < 0.05). At 20 mAs, there were significant differences between the RD and LD scans for all parameters in the ischemic and normal tissue regions (p > 0.05). CTP-derived CBF and CBV are not different at 50 mAs compared to 100 mAs, even without the addition of ASIR. Current CTP protocols can be modified to reduce the effective dose by 50 % without altering CTP measurements. (orig.)

  15. CT perfusion in acute stroke calls: a pictorial review and differential diagnoses

    International Nuclear Information System (INIS)

    Chiu, Albert H; Phillips, Timothy J.; Phatouros, Constantine C.; Singh, Tejinder P.; McAuliffe, William; Hankey, Graeme; Blacker, David J.

    2016-01-01

    CT perfusion is increasingly utilised in hyperacute stroke to facilitate diagnosis and patient selection for reperfusion therapies. This review article demonstrates eight examples of how CT perfusion can be used to diagnose stroke mimics and small volume infarcts, which can be easily missed on non-contrast CT, and to suggest the presence of an ischaemic penumbra. Radiologists involved in stroke management must understand the importance of rapid imaging acquisition and be confident in the prospective interpretation of this powerful diagnostic tool as we move into a new era of hyperacute stroke care.

  16. Hemodynamic effects of decompressive craniotomy in MCA infarction: evaluation with perfusion CT

    Energy Technology Data Exchange (ETDEWEB)

    Bendszus, Martin; Weigand, Alexandra; Solymosi, Laszlo [Department of Neuroradiolgoy, University of Wuerzburg, Josef-Schneider-Strasse 11, 97080 Wuerzburg (Germany); Muellges, Wolfgang [Department of Neurology, University of Wuerzburg, Josef-Schneider-Strasse 11, 97080 Wuerzburg (Germany); Goldbrunner, Roland [Department of Neurosurgery, University of Wuerzburg, Josef-Schneider-Strasse 11, 97080 Wuerzburg (Germany)

    2003-08-01

    Decompressive craniotomy in hemispheric infarction has been reported to reduce mortality and improve outcome. Identifying tissue at risk and monitoring the benefit of craniotomy is hardly practical and has not been reported thus far. Perfusion CT was applied before and immediately after decompressive craniotomy in a patient with space-occupying middle cerebral artery (MCA) infarction. Before surgery, perfusion CT revealed malperfused but still vital tissue in the vicinity of the infarction core which returned to normal after decompressive surgery. The final infarct size did not exceed the area of the initial hypodensity on unenhanced CT scan. In critically ill patients, the practicability of perfusion CT allows for demonstration of tissue at risk around the infarct core in space-occupying MCA infarction. Moreover, it may be used to monitor the effect of decompressive craniotomy. (orig.)

  17. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan); Fujisawa, Yasuko [Toshiba Medical Systems Corporation, Otawara (Japan); Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Sugihara, Naoki [Toshiba Medical Systems Corporation, Otawara (Japan); Yoshikawa, Takeshi [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan)

    2017-01-15

    Purpose: To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Materials and methods: Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR + PR) and 2) stable or progressive disease (SD + PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV{sub max}, and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. Results: The step-wise regression test showed that therapeutic effect (r{sup 2} = 0.63, p = 0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV{sub max}. Mean overall survival showed a significant difference for total perfusion (p = 0.003) and systemic arterial perfusion (p = 0.04). Conclusion: Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy.

  18. Dynamic volume perfusion CT in patients with lung cancer: Baseline perfusion characteristics of different histological subtypes

    International Nuclear Information System (INIS)

    Shi, Jingyun; Schmid-Bindert, Gerald; Fink, Christian; Sudarski, Sonja; Apfaltrer, Paul; Pilz, Lothar R.; Liu, Bo; Haberland, Ulrike; Klotz, Ernst

    2013-01-01

    Objective: To evaluate dynamic volume perfusion CT (dVPCT) tumor baseline characteristics of three different subtypes of lung cancer in untreated patients. Materials and methods: 173 consecutive patients (131 men, 42 women; mean age 61 ± 10 years) with newly diagnosed lung cancer underwent dVPCT prior to biopsy. Tumor permeability, blood flow (BF), blood volume (BV) and mean transit time (MTT) were quantitatively assessed as well as tumor diameter and volume. Tumor subtypes were histologically determined and compared concerning their dVPCT results. dVPCT results were correlated to tumor diameter and volume. Results: Histology revealed adenocarcinoma in 88, squamous cell carcinoma in 54 and small cell lung cancer (SCLC) in 31 patients. Tumor permeability was significantly differing between adenocarcinoma, squamous cell carcinoma and SCLC (all p < 0.05). Tumor BF and BV were higher in adenocarcinomathan in SCLC (p = 0.001 and p = 0.0002 respectively). BV was also higher in squamous cell carcinoma compared to SCLC (p = 0.01). MTT was not differing between tumor subtypes. Regarding all tumors, tumor diameter did not correlate with any of the dVPCT parameters, whereas tumor volume was negatively associated with permeability, BF and BV (r = −0.22, −0.24, −0.24, all p < 0.05). In squamous cell carcinoma, tumor diameter und volume correlated with BV (r = 0.53 and r = −0.40, all p < 0.05). In SCLC, tumor diameter und volume correlated with MTT (r = 0.46 and r = 0.39, all p < 0.05). In adenocarcinoma, no association between morphological and functional tumor characteristics was observed. Conclusions: dVPCT parameters are only partially related to tumor diameter and volume and are significantly differing between lung cancer subtypes

  19. Differential Diagnosis of Lymphadenopathy in the Neck Spaces in a CT Perfusion Study

    Energy Technology Data Exchange (ETDEWEB)

    Rhee, Sun Jung; Hong, Hyun Sook; Lee, Eun Hye; Lee, Min Hee [Dept. of Radiology, Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Park, Jung Mi [Dept. of Nuclear Science, Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of)

    2011-11-15

    To evaluate the CT perfusion parameters for differentiating between a benign and malignant lymphadenopathy in the neck spaces. Seventeen patients with cervical lymphadenopathy underwent perfusion CT. Perfusion parameters, including blood flow (BF), blood volume (BV), permeability index (PI), and mean transit time, were calculated at the regions of interest in the enlarged lymph nodes (LNs). The enlarged LNs were diagnosed by fine needle aspiration, surgical excision, and clinical follow-up. The LNs were classified as either reactive hyperplasia (n = 26), metastatic LNs (n = 11), or LNs of lymphoma (n = 14). Significant differences were found for BF, BV, and PI among the three groups (p < 0.05). Reactive hyperplasia had a significantly higher BF than metastatic LN (p < 0.0167). The LNs of lymphoma had a significantly lower BF, BV, and PI than reactive hyperplasia (p < 0.0167). No significant difference was observed between the metastatic LNs of the head and neck cancer and LNs of lymphoma for all perfusion parameters. In patients with head and neck cancer, perfusion CT is not useful for differentiating between metastatic LNs and inflammatory reactive hyperplasia. However, perfusion CT can be useful for differentiating between LNs of lymphoma and reactive hyperplasia.

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

    Directory of Open Access Journals (Sweden)

    Daniela Muenzel

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

  1. Dynamic CT Perfusion Imaging of the Myocardium: A Technical Note on Improvement of Image Quality

    Science.gov (United States)

    Gramer, Bettina; Leber, Vivian; Vembar, Mani; Schmitt, Holger; Wildgruber, Moritz; Fingerle, Alexander A.; Rummeny, Ernst J.; Huber, Armin; Noël, Peter B.

    2013-01-01

    Objective To improve image and diagnostic quality in dynamic CT myocardial perfusion imaging (MPI) by using motion compensation and a spatio-temporal filter. Methods Dynamic CT MPI was performed using a 256-slice multidetector computed tomography scanner (MDCT). Data from two different patients–with and without myocardial perfusion defects–were evaluated to illustrate potential improvements for MPI (institutional review board approved). Three datasets for each patient were generated: (i) original data (ii) motion compensated data and (iii) motion compensated data with spatio-temporal filtering performed. In addition to the visual assessment of the tomographic slices, noise and contrast-to-noise-ratio (CNR) were measured for all data. Perfusion analysis was performed using time-density curves with regions-of-interest (ROI) placed in normal and hypoperfused myocardium. Precision in definition of normal and hypoperfused areas was determined in corresponding coloured perfusion maps. Results The use of motion compensation followed by spatio-temporal filtering resulted in better alignment of the cardiac volumes over time leading to a more consistent perfusion quantification and improved detection of the extend of perfusion defects. Additionally image noise was reduced by 78.5%, with CNR improvements by a factor of 4.7. The average effective radiation dose estimate was 7.1±1.1 mSv. Conclusion The use of motion compensation and spatio-temporal smoothing will result in improved quantification of dynamic CT MPI using a latest generation CT scanner. PMID:24130697

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  3. Evaluation of peripheral pulmonary perfusion decrease of 99m-Tc MAA scintigraphy using SPECT/CT

    International Nuclear Information System (INIS)

    Yoneyama, Tatsuya; Kamisaki, Yuichi; Kameda, Keisuke; Seto, Hikaru

    2012-01-01

    We often experienced non-segmented peripheral patchy decrease (NSPPD) in 99m Tc-macro-aggregated albumin (MAA) pulmonary perfusion scan using single photon emission computed tomography (SPECT)/CT. Seventy cases were evaluated by 99m Tc-MAA SPECT/CT. NSPPD was seen in 22 cases (31.4%), of which 17 were assessed for pulmonary hypertension. Pulmonary hypertension was diagnosed in 11 cases, which consisted of 3 chronic thromboembolic pulmonary hypertension, 2 idiopathic pulmonary arterial hypertension, 2 systemic lupus eryhthematosus and 4 left ventricular heart disease. We suggest that NSPPD may indicate the early stage of pulmonary hypertension (PH). (author)

  4. Assessment of pancreatic adenocarcinoma: use of low-dose whole pancreatic CT perfusion and individualized dual-energy CT scanning

    International Nuclear Information System (INIS)

    Li, Hai-ou; Guo, Jun; Li, Xiao; Qi, Yao-dong; Wang, Xi-ming; Xu, Zhuo-dong; Liu, Cheng; Chen, Jiu-hong

    2015-01-01

    The objective of this study was to investigate the value of low-dose whole pancreatic computed tomography (CT) perfusion integrated with individualized dual-energy CT (DECT) scanning in the diagnosis of pancreatic adenocarcinoma. Twenty patients with pancreatic adenocarcinoma underwent pancreatic CT perfusion as well as individualized dual-phase DECT pancreatic scans. Perfusion characteristics of non-tumourous pancreatic parenchyma and pancreatic adenocarcinoma were analysed. Weighted-average 120 kVp images and the optimal monoenergetic images in dual phase were reconstructed and the contrast noise ratio (CNR) of pancreas-to-tumour were compared. There were significant difference on blood flow as well as blood volume between pancreatic adenocarcinoma and the non-tumourous pancreatic parenchyma (P < 0.05), whereas no difference on permeability (P > 0.05). CNRs of pancreas-to-tumour in individualized pancreatic phase were significantly higher than those in venous phase (P < 0.05), and CNRs of optimal monoenergetic images were higher than those on weighted-average 120 kVp images (P < 0.05) in both phase. Total effective radiation dose of CT examination was around 9.32–13.75 mSv. Low-dose whole pancreatic CT perfusion can provide functional information, and the individualized pancreatic phase DECT scan is the optimal method for detecting pancreatic adenocarcinomas. The integration of the two techniques has great value in clinical application.

  5. Machine-learning based comparison of CT-perfusion maps and dual energy CT for pancreatic tumor detection

    Science.gov (United States)

    Goetz, Michael; Skornitzke, Stephan; Weber, Christian; Fritz, Franziska; Mayer, Philipp; Koell, Marco; Stiller, Wolfram; Maier-Hein, Klaus H.

    2016-03-01

    Perfusion CT is well-suited for diagnosis of pancreatic tumors but tends to be associated with a high radiation exposure. Dual-energy CT (DECT) might be an alternative to perfusion CT, offering correlating contrasts while being acquired at lower radiation doses. While previous studies compared intensities of Dual Energy iodine maps and CT-perfusion maps, no study has assessed the combined discriminative power of all information that can be generated from an acquisition of both functional imaging methods. We therefore propose the use of a machine learning algorithm for assessing the amount of information that becomes available by the combination of multiple images. For this, we train a classifier on both imaging methods, using a new approach that allows us to train only from small regions of interests (ROIs). This makes our study comparable to other - ROI-based analysis - and still allows comparing the ability of both classifiers to discriminate between healthy and tumorous tissue. We were able to train classifiers that yield DICE scores over 80% with both imaging methods. This indicates that Dual Energy Iodine maps might be used for diagnosis of pancreatic tumors instead of Perfusion CT, although the detection rate is lower. We also present tumor risk maps that visualize possible tumorous areas in an intuitive way and can be used during diagnosis as an additional information source.

  6. Whole brain CT perfusion combined with CT angiography in patients with subarachnoid hemorrhage and cerebral vasospasm.

    Science.gov (United States)

    Zhang, He; Zhang, Bo; Li, Shu; Liang, Chuansheng; Xu, Ke; Li, Songbai

    2013-12-01

    To assess cerebral vasospasm (CVS) and monitor cerebral microcirculatory changes in patients with acute subarachnoid hemorrhage (SAH) via CT angiography (CTA) combined with whole-brain CT perfusion (CTP) techniques. Sixty patients with SAH (SAH group) and 10 patients without SAH (control group) were selected for a prospective study. CTP combined with CTA and digital subtraction angiography (DSA) studies were performed on patients with initial onset of SAH less than three days. CTA and DSA as well as the CTP parameters such as cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time-to-peak (TTP) were acquired and analyzed. The relationship of CTA and CTP measurements was assessed in these acute SAH patients. CTP techniques were used to achieve the perfusion maps of the whole brain in patients with acute SAH. Compared to the control group, mean CBF value was significantly lower while both MTT and TTP values were significantly higher in SAH group (all p<0.05). Further analysis revealed that mean CBF in patients with CVS, sCVS, Fisher III-IV and Hunt-Hess III-V significantly decreased when compared to patients with nCVS, asCVS, Fisher I-II and Hunt-Hess I-II (p<0.05). Furthermore both MTT and TTP values were also significantly reduced in patient with CVS, sCVS, Fisher III-IV and Hunt-Hess III-V (p<0.05). The study demonstrated that changes of microcirculation in patients with SAH could be assessed by whole-brain CTP. CTP combined with CTA could detect both macroscopic evident vasospasm on CTA and alterations of microcirculation on CTP. Mean CBF was significantly lower in patients with SAH. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. A 4D digital phantom for patient-specific simulation of brain CT perfusion protocols.

    Science.gov (United States)

    van den Boom, Rieneke; Manniesing, Rashindra; Oei, Marcel T H; van der Woude, Willem-Jan; Smit, Ewoud J; Laue, Hendrik O A; van Ginneken, Bram; Prokop, Mathias

    2014-07-01

    Optimizing CT brain perfusion protocols is a challenge because of the complex interaction between image acquisition, calculation of perfusion data, and patient hemodynamics. Several digital phantoms have been developed to avoid unnecessary patient exposure or suboptimum choice of parameters. The authors expand this idea by using realistic noise patterns and measured tissue attenuation curves representing patient-specific hemodynamics. The purpose of this work is to validate that this approach can realistically simulate mean perfusion values and noise on perfusion data for individual patients. The proposed 4D digital phantom consists of three major components: (1) a definition of the spatial structure of various brain tissues within the phantom, (2) measured tissue attenuation curves, and (3) measured noise patterns. Tissue attenuation curves were measured in patient data using regions of interest in gray matter and white matter. By assigning the tissue attenuation curves to the corresponding tissue curves within the phantom, patient-specific CTP acquisitions were retrospectively simulated. Noise patterns were acquired by repeatedly scanning an anthropomorphic skull phantom at various exposure settings. The authors selected 20 consecutive patients that were scanned for suspected ischemic stroke and constructed patient-specific 4D digital phantoms using the individual patients' hemodynamics. The perfusion maps of the patient data were compared with the digital phantom data. Agreement between phantom- and patient-derived data was determined for mean perfusion values and for standard deviation in de perfusion data using intraclass correlation coefficients (ICCs) and a linear fit. ICCs ranged between 0.92 and 0.99 for mean perfusion values. ICCs for the standard deviation in perfusion maps were between 0.86 and 0.93. Linear fitting yielded slope values between 0.90 and 1.06. A patient-specific 4D digital phantom allows for realistic simulation of mean values and

  8. Renal versus splenic maximum slope based perfusion CT modelling in patients with portal-hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Michael A. [University Hospital Zurich, Department of Diagnostic and Interventional Radiology, Zurich (Switzerland); Karolinska Institutet, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Stockholm (Sweden); Brehmer, Katharina [Karolinska University Hospital Huddinge, Department of Radiology, Stockholm (Sweden); Svensson, Anders; Aspelin, Peter; Brismar, Torkel B. [Karolinska Institutet, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Stockholm (Sweden); Karolinska University Hospital Huddinge, Department of Radiology, Stockholm (Sweden)

    2016-11-15

    To assess liver perfusion-CT (P-CT) parameters derived from peak-splenic (PSE) versus peak-renal enhancement (PRE) maximum slope-based modelling in different levels of portal-venous hypertension (PVH). Twenty-four patients (16 men; mean age 68 ± 10 years) who underwent dynamic P-CT for detection of hepatocellular carcinoma (HCC) were retrospectively divided into three groups: (1) without PVH (n = 8), (2) with PVH (n = 8), (3) with PVH and thrombosis (n = 8). Time to PSE and PRE and arterial liver perfusion (ALP), portal-venous liver perfusion (PLP) and hepatic perfusion-index (HPI) of the liver and HCC derived from PSE- versus PRE-based modelling were compared between the groups. Time to PSE was significantly longer in PVH groups 2 and 3 (P = 0.02), whereas PRE was similar in groups 1, 2 and 3 (P > 0.05). In group 1, liver and HCC perfusion parameters were similar for PSE- and PRE-based modelling (all P > 0.05), whereas significant differences were seen for PLP and HPI (liver only) in group 2 and ALP in group 3 (all P < 0.05). PSE is delayed in patients with PVH, resulting in a miscalculation of PSE-based P-CT parameters. Maximum slope-based P-CT might be improved by replacing PSE with PRE-modelling, whereas the difference between PSE and PRE might serve as a non-invasive biomarker of PVH. (orig.)

  9. Perfusion CT - A novel quantitative and qualitative imaging biomarker in gastric cancer.

    Science.gov (United States)

    Kruk-Bachonko, Joanna; Krupski, Witold; Czechowski, Michał; Kurys-Denis, Ewa; Mądro, Przemysław; Sierocińska-Sawa, Jadwiga; Dąbrowski, Andrzej; Wallner, Grzegorz; Skoczylas, Tomasz

    2017-10-01

    The aim of this research was to examine whether Perfusion Computed Tomography (P-CT) can qualitatively and quantitatively help detect gastric cancer neoangiogenesis in vivo as well as treatment response evaluation. We attempted to explore which P-CT parameters are best used in neoangiogenesis and neoadjuvant therapy for most effective evaluation. We also tried to recognize a positive prediction value of P-CT in early responders and non-responders patients identification. Twenty-four patients with positive biopsy results and/or clinically proven gastric cancer were enrolled in the P-CT exam. Patients were qualified for systemic treatment (16 patients received chemotherapy and 8 patients received radiochemotherapy). The baseline Perfusion-CT exam and after neoadjuvant treatment Perfusion-CT exam were conducted using a 64-row GE tomograph based on a deconvolution model in first-pass protocol perfusion. The P-CT examined the following parameters: Blood Flow (BF), Blood Volume (BV), Mean Transit Time (MTT) and Permeability Surface (PS). Positive clinical response to neoadjuvant treatment (CHT and RCT) was defined as tumor size reduction 25% or more. Tumor dimension reduction after neoadjuvant therapy was significantly correlated with the BF and the PS. Neoadjuvant therapy was more effective for patients with higher output BF and PS values. We did not register a significant relationship between BV and MTT parameters and tumor dimension reduction. Patients with a positive treatment response showed a decrease in BF, BV and PS perfusion parameters with an increase in MTT. P-CT examination allows a noninvasive neoangiogenesis assessment in vivo, leading to early identification of responding and non-responding patients. As a standard procedure, a full evaluation of treatment response should include a P-CT exam assessing neoangiogenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Perfusion CT in acute stroke: effectiveness of automatically-generated colour maps.

    Science.gov (United States)

    Ukmar, Maja; Degrassi, Ferruccio; Pozzi Mucelli, Roberta Antea; Neri, Francesca; Mucelli, Fabio Pozzi; Cova, Maria Assunta

    2017-04-01

    To evaluate the accuracy of perfusion CT (pCT) in the definition of the infarcted core and the penumbra, comparing the data obtained from the evaluation of parametric maps [cerebral blood volume (CBV), cerebral blood flow (CBF) and mean transit time (MTT)] with software-generated colour maps. A retrospective analysis was performed to identify patients with suspected acute ischaemic strokes and who had undergone unenhanced CT and pCT carried out within 4.5 h from the onset of the symptoms. A qualitative evaluation of the CBV, CBF and MTT maps was performed, followed by an analysis of the colour maps automatically generated by the software. 26 patients were identified, but a direct CT follow-up was performed only on 19 patients after 24-48 h. In the qualitative analysis, 14 patients showed perfusion abnormalities. Specifically, 29 perfusion deficit areas were detected, of which 15 areas suggested the penumbra and the remaining 14 areas suggested the infarct. As for automatically software-generated maps, 12 patients showed perfusion abnormalities. 25 perfusion deficit areas were identified, 15 areas of which suggested the penumbra and the other 10 areas the infarct. The McNemar's test showed no statistically significant difference between the two methods of evaluation in highlighting infarcted areas proved later at CT follow-up. We demonstrated how pCT provides good diagnostic accuracy in the identification of acute ischaemic lesions. The limits of identification of the lesions mainly lie at the pons level and in the basal ganglia area. Qualitative analysis has proven to be more efficient in identification of perfusion lesions in comparison with software-generated maps. However, software-generated maps have proven to be very useful in the emergency setting. Advances in knowledge: The use of CT perfusion is requested in increasingly more patients in order to optimize the treatment, thanks also to the technological evolution of CT, which now allows a whole

  11. CT Perfusion with Acetazolamide Challenge in C6 Gliomas and Angiogenesis

    Science.gov (United States)

    Feng, Xiao-Yuan; Qiang, Jin-Wei; Zhang, Jia-wen; Wang, Yong-gang; Liu, Ying

    2015-01-01

    Background This study was performed to investigate the correlation between CT perfusion with acetazolamide challenge and angiogenesis in C6 gliomas. Methods Thirty-two male Sprague-Dawley rats were evaluated. The rats were divided randomly to four groups: eight rats with orthotopically implanted C6 gliomas at 10-days old (Group A), eight rats with gliomas at 14-days old (Group B), eight rats with gliomas at 18-days old (Group C), eight rats with orthotopically injected normal saline served as controls. CT perfusion was performed before and after administration of acetazolamide. Changes in perfusion parameters due to acetazolamide administration were calculated and analyzed. Results Elevated carbon dioxide partial pressure and decreased pH were found in all 32 rats post acetazolamide challenge (PCT perfusion with challenge can provide new insight into non-invasive assessment of rat C6 glioma angiogenesis. PMID:25781321

  12. Association of CT perfusion imaging with plasma levels of TGF-β1 and VEGF in patients with NSCLC.

    Science.gov (United States)

    Li, Da-Wei; Wu, Bao-Zhong; Shi, Yu-Sen; Li, Zhi-Qun; Liu, Xu-Dong; Li, Xiao-Hua

    2016-02-01

    To study the association of CT perfusion imaging parameters with plasma level of transforming growth factor-β1 (TGF-β1) and vascular endothelial growth (VEGF) in patients with non small cell lung cancer (NSCLC). A total of 67 patients with NSCLC (NSCLC group) and 64 patients with benign lesion (control group) were given with CT perfusion imaging to obtain blood flow, blood volume, mean transit time, time to peal and permeability surface through CT perfusion software. The plasma levels of TGF-β1 and VEGF were tested by ELISA. The relationship between plasma levels of TGF-β1, VEGF and CT perfusion imaging parameters were analyzed. CT perfusion imaging parameters and the plasma levels of TGF-β1 and VEGF of NSCLC group were significantly higher than the control group (P CT perfusion parameters and the levels of TGF-β1 and VEGF in NSCLC group showed significant difference in different tumor node metastasis stages (P CT perfusion imaging parameters in patients with NSCLC is closely associated with plasma TGF-β1, VEGF and its biological characteristics. CT perfusion imaging is a convenient method to detect tumor blood perfusion. Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

  13. Correlation Between Dual-energy and Perfusion CT in Patients with Focal Liver Lesions Using Third-generation Dual-source CT Scanner.

    Science.gov (United States)

    Xu, Jia; Zheng, Yongchang; Wang, Xuan; Xue, Huadan; Wang, Shitian; Liang, Jixiang; Jin, Zhengyu

    2017-02-20

    Objective To compare measurements of dual-energy CT iodine map parameters and liver perfusion CT parameters in patients with focal liver lesions using a third-generation dual-source CT scanner. Methods Between November 2015 and August 2016,33 patients with non-cystic focal lesions of liver were enrolled in this study. CT examinations were performed with a third-generation dual-source CT. The study CT protocol included a perfusion CT and dual-energy arterial and portal venous scans,with a time interval of 15 minutes. Iodine attenuation was measured at five region of interests including areas of high,medium,and low density within the lesion,as well as right and left liver parenchyma from the iodine map,while arterial liver perfusion (ALP),portal venous liver perfusion (PVP),and hepatic perfusion index (HPI) at the same location were measured from perfusion CT. The Pearson product-moment correlation coefficient was used to evaluate the relationship between iodine attenuation and perfusion parameters. Results The iodine attenuation at arterial phase showed significant intra-individual correlation with ALP (r=0.812,95% CI=0.728-0.885,PCT together [(3.53±1.17)mSv] was significantly lower than that of the perfusion CT [(14.53±0.45)mSv](t=25.212,PCT demonstrates significant correlation with ALP and PVP,and iodine attenuation from portal venous phase demonstrates significant correlation with PVP.

  14. Dual-Energy Perfusion-CT in Recurrent Pancreatic Cancer - Preliminary Results.

    Science.gov (United States)

    Fritz, F; Skornitzke, S; Hackert, T; Kauczor, H U; Stiller, W; Grenacher, L; Klauss, M

    2016-06-01

    To evaluate the diagnostic performance of dual energy (DE) perfusion-CT for the differentiation between postoperative soft-tissue formation and tumor recurrence in patients after potentially curative pancreatic cancer resection. 24 patients with postoperative soft-tissue formation in the conventional regular follow-up CT acquisition after pancreatic cancer resection with curative intent were included prospectively. They were examined with a 64-row dual-source CT using a dynamic sequence of 34 DE acquisitions every 1.5 s (80 ml of iodinated contrast material, 370 mg/ml, flow rate 5 ml/s). Weighted average (linearly blended M0.5) 120kVp-equivalent dual-energy perfusion image data sets were evaluated with a body-perfusion CT tool (see above) for estimating blood flow, permeability, and blood volume. Diagnosis was confirmed by histological study (n = 4) and by regular follow-up. Final diagnosis was local recurrence of pancreatic cancer in 15 patients and unspecific postoperative tissue formation in 9 patients. The blood-flow values for recurrence tissue trended to be lower compared to postoperative tissue formation with 16.6 ml/100 ml/min and 24.7 ml/100 ml/min, respectively for weighted average 120kVp-equivalent image data, which was not significant (n.s.) (p = 0.06, significance level 0.05). Permeability- and blood-volume values were only slightly lower in recurrence tissue (n.s.). DE perfusion-CT is feasible in patients after pancreatic cancer resection and a promising functional imaging technique. As only a trend for lower perfusion values in local recurrence compared to unspecific postoperative alterations was found, the perfusion differences are not yet sufficient to differentiate between malignancy and unspecific postoperative alterations for this new technique. Further studies and technical improvements are needed to generate reliable data for this clinically highly relevant differentiation. • DE Perfusion CT is feasible in patients

  15. Robust Low-dose CT Perfusion Deconvolution via Tensor Total-Variation Regularization

    Science.gov (United States)

    Zhang, Shaoting; Chen, Tsuhan; Sanelli, Pina C.

    2016-01-01

    Acute brain diseases such as acute strokes and transit ischemic attacks are the leading causes of mortality and morbidity worldwide, responsible for 9% of total death every year. ‘Time is brain’ is a widely accepted concept in acute cerebrovascular disease treatment. Efficient and accurate computational framework for hemodynamic parameters estimation can save critical time for thrombolytic therapy. Meanwhile the high level of accumulated radiation dosage due to continuous image acquisition in CT perfusion (CTP) raised concerns on patient safety and public health. However, low-radiation leads to increased noise and artifacts which require more sophisticated and time-consuming algorithms for robust estimation. In this paper, we focus on developing a robust and efficient framework to accurately estimate the perfusion parameters at low radiation dosage. Specifically, we present a tensor total-variation (TTV) technique which fuses the spatial correlation of the vascular structure and the temporal continuation of the blood signal flow. An efficient algorithm is proposed to find the solution with fast convergence and reduced computational complexity. Extensive evaluations are carried out in terms of sensitivity to noise levels, estimation accuracy, contrast preservation, and performed on digital perfusion phantom estimation, as well as in-vivo clinical subjects. Our framework reduces the necessary radiation dose to only 8% of the original level and outperforms the state-of-art algorithms with peak signal-to-noise ratio improved by 32%. It reduces the oscillation in the residue functions, corrects over-estimation of cerebral blood flow (CBF) and under-estimation of mean transit time (MTT), and maintains the distinction between the deficit and normal regions. PMID:25706579

  16. CT perfusion illustrated reversal of uncal herniation after placement of an external ventricular drain

    Directory of Open Access Journals (Sweden)

    Ulus Baran, MD

    2015-12-01

    Full Text Available Compression of the PCA in the context of uncal herniation is usually deducted in retrospect only with presence of a demarcated infarction in the respective territory. In this particular case with early recovery of oculomotor nerve function after CSF drainage, additional CT perfusion was able to directly document both significant compromise of the PCA as well as effective reversal of uncal herniation with restitution of perfusion within the PCA territory.

  17. 320-row CT renal perfusion imaging in patients with aortic dissection: A preliminary study.

    Science.gov (United States)

    Liu, Dongting; Liu, Jiayi; Wen, Zhaoying; Li, Yu; Sun, Zhonghua; Xu, Qin; Fan, Zhanming

    2017-01-01

    To investigate the clinical value of renal perfusion imaging in patients with aortic dissection (AD) using 320-row computed tomography (CT), and to determine the relationship between renal CT perfusion imaging and various factors of aortic dissection. Forty-three patients with AD who underwent 320-row CT renal perfusion before operation were prospectively enrolled in this study. Diagnosis of AD was confirmed by transthoracic echocardiography. Blood flow (BF) of bilateral renal perfusion was measured and analyzed. CT perfusion imaging signs of AD in relation to the type of AD, number of entry tears and the false lumen thrombus were observed and compared. The BF values of patients with type A AD were significantly lower than those of patients with type B AD (P = 0.004). No significant difference was found in the BF between different numbers of intimal tears (P = 0.288), but BF values were significantly higher in cases with a false lumen without thrombus and renal arteries arising from the true lumen than in those with thrombus (P = 0.036). The BF values measured between the true lumen, false lumen and overriding groups were different (P = 0.02), with the true lumen group having the highest. Also, the difference in BF values between true lumen and false lumen groups was statistically significant (P = 0.016), while no statistical significance was found in the other two groups (P > 0.05). The larger the size of intimal entry tears, the greater the BF values (P = 0.044). This study shows a direct correlation between renal CT perfusion changes and AD, with the size, number of intimal tears, different types of AD, different renal artery origins and false lumen thrombosis, significantly affecting the perfusion values.

  18. Hypovolemic shock complex: does the pancreatic perfusion increase or decrease at contrast-enhanced dynamic CT?

    Science.gov (United States)

    Higashi, Hiroki; Tamada, Tsutomu; Kanki, Akihiko; Yamamoto, Akira; Ito, Katsuyoshi

    2014-01-01

    The purpose of this study is to evaluate contrast enhancement effects of the pancreas at dynamic computed tomography (CT) to clarify whether pancreatic perfusion increases or decreases in severe trauma patients with hypovolemic shock. A total of 90 patients with (n=30) and without (n=60) blunt trauma and hypovolemic shock who underwent dynamic CT for abdomen was included. The measurement of CT attenuation values of the pancreas in the early phase and the late phase was performed to compare the contrast enhancement effects between patients with and without hypovolemic shock. The mean CT attenuation values of the pancreas in the early phase of dynamic CT in patients with hypovolemic shock [95.4±29.1 Hounsfield units (HU)] were significantly lower (P perfusion in patients with hypovolemic shock. The mean CT attenuation values of the pancreas in the late phase of dynamic CT in patients with hypovolemic shock (95.9±17.6 HU) were significantly higher (P perfusion in the early phase and delayed pancreatic enhancement in the late phase of contrast-enhanced dynamic CT was a common finding in patients with hypovolemic shock. © 2014.

  19. Role of CT perfusion imaging in patients with variously differentiated gastric adenocarcinoma.

    Science.gov (United States)

    Sun, Zong-Qiong; Cheng, Xiao-Fang; Ge, Yu-Xi; Chen, Lin; Yue, Jian-Guo; Jin, Lin-Fang; Xie, Zhi-Hui; Zhang, Han-Di; Xuan, Ying-Hua

    2015-01-01

    To explore the characteristics of variously differentiated gastric cancers on computed tomography (CT) perfusion imaging, including specific perfusion parameter values, and potential clinical applications in the prognosis assessment of gastric cancer. Fifty patients with gastric cancer confirmed by gastroscope pathology were studied prospectively using CT perfusion imaging examinations on a 64-slice spiral CT scanner. The acquired volume data were used for calculations, mapping, and analysis by using an abdominal tumor perfusion protocol (deconvolution method) in the CT perfusion software package to measure 4 parameters: blood flow (BF), blood volume (BV), mean transit time (MTT), and the permeability surface (PS) area product. The different differentiated Gastric cancers with CT perfusion values were divided into 3 groups: well-differentiated, moderately differentiated and poorly differentiated gastric adenocarcinoma, and compared statistically with one another by statistical software. The mean perfusion values of 10 patients with well-differentiated gastric adenocarcinoma were as follows: BF, 75.28 ± 6.81 mL/100 g/min; BV, 9.01 ± 0.94 mL/100 g; MTT, 9.89 ± 1.65 s; and PS, 10.05 ± 0.71 mL/100 g/min. The mean perfusion values of 24 patients with moderately differentiated gastric adenocarcinoma were as follows: BF, 110.01 ± 31.90 mL/100 g/min; BV, 18.18 ± 5.62 mL/100 g; MTT, 9.81 ± 3.69 s; and PS, 40.08 ± 15.82 mL/100 g/min. The mean perfusion values of 16 patients with poorly differentiated gastric adenocarcinoma were as follows: BF, 138.59 ± 38.09 mL/100 g/min; BV, 21.08 ± 4.11 mL/100 g; MTT, 9.47 ± 1.80 s; and PS, 57.50 ± 13.28 mL/100 g/min. Comparing the 3 groups, differences between the well-differentiated group and the moderate differentiation group were all statistically significant for BF, BV, and PS (p 0.05). Stomach CT perfusion imaging is a functional imaging technology from the perspective of hemodynamics with potential clinical applications

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

    International Nuclear Information System (INIS)

    Goh, Vicky; Shastry, Manu; Endozo, Raymondo; Groves, Ashley M.; Engledow, Alec; Peck, Jacqui; Reston, Jonathan; Wellsted, David M.; Rodriguez-Justo, Manuel; Taylor, Stuart A.; Halligan, Steve

    2011-01-01

    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.)

  1. Role of dynamic CT perfusion study in evaluating various intracranial space-occupying lesions

    Directory of Open Access Journals (Sweden)

    Ravindra B Kamble

    2015-01-01

    Full Text Available Aims: Differentiating intracranial mass lesions on CT scan is challenging. The purpose of our study was to determine the perfusion parameters in various intracranial space-occupying lesions (ICSOL, differentiate benign and malignant lesions, and differentiate between grades of gliomas. Materials and Methods: We performed CT perfusion (CTP in 64 patients, with age ranging from 17 to 68 years, having space-occupying lesions in brain and calculated relative cerebral blood flow (rCBF and relative cerebral blood volume (rCBV. Results: We found significantly lower perfusion in low-grade gliomas as compared to high-grade tumors, lymphoma, and metastases. Similarly in infective lesions, TWT and abscesses showed significantly lower perfusion compared to TOT. In ring enhancing lesions, capsule of TWT showed significantly lower perfusion as compared to abscesses, TOT, and metastases. Conclusion: Thus, in conclusion, infective lesions can be differentiated from tumors like lymphomas, high-grade gliomas, or metastases based on perfusion parameters. The cut off value of rCBV 1.64 can be used to differentiate between low grade and high grade gliomas. However, depending only on perfusion parameters, differentiation between the tumors like lymphomas, high-grade gliomas, and metastases may not be possible.

  2. Low-dose dynamic myocardial perfusion CT image reconstruction using pre-contrast normal-dose CT scan induced structure tensor total variation regularization

    Science.gov (United States)

    Gong, Changfei; Han, Ce; Gan, Guanghui; Deng, Zhenxiang; Zhou, Yongqiang; Yi, Jinling; Zheng, Xiaomin; Xie, Congying; Jin, Xiance

    2017-04-01

    Dynamic myocardial perfusion CT (DMP-CT) imaging provides quantitative functional information for diagnosis and risk stratification of coronary artery disease by calculating myocardial perfusion hemodynamic parameter (MPHP) maps. However, the level of radiation delivered by dynamic sequential scan protocol can be potentially high. The purpose of this work is to develop a pre-contrast normal-dose scan induced structure tensor total variation regularization based on the penalized weighted least-squares (PWLS) criteria to improve the image quality of DMP-CT with a low-mAs CT acquisition. For simplicity, the present approach was termed as ‘PWLS-ndiSTV’. Specifically, the ndiSTV regularization takes into account the spatial-temporal structure information of DMP-CT data and further exploits the higher order derivatives of the objective images to enhance denoising performance. Subsequently, an effective optimization algorithm based on the split-Bregman approach was adopted to minimize the associative objective function. Evaluations with modified dynamic XCAT phantom and preclinical porcine datasets have demonstrated that the proposed PWLS-ndiSTV approach can achieve promising gains over other existing approaches in terms of noise-induced artifacts mitigation, edge details preservation, and accurate MPHP maps calculation.

  3. Whole-Brain CT Perfusion to Quantify Acute Ischemic Penumbra and Core.

    Science.gov (United States)

    Lin, Longting; Bivard, Andrew; Krishnamurthy, Venkatesh; Levi, Christopher R; Parsons, Mark W

    2016-06-01

    Purpose To validate the use of perfusion computed tomography (CT) with whole-brain coverage to measure the ischemic penumbra and core and to compare its performance to that of limited-coverage perfusion CT. Materials and Methods Institutional ethics committee approval and informed consent were obtained. Patients (n = 296) who underwent 320-detector CT perfusion within 6 hours of the onset of ischemic stroke were studied. First, the ischemic volume at CT perfusion was compared with the penumbra and core reference values at magnetic resonance (MR) imaging to derive CT perfusion penumbra and core thresholds. Second, the thresholds were tested in a different group of patients to predict the final infarction at diffusion-weighted imaging 24 hours after CT perfusion. Third, the change in ischemic volume delineated by the optimal penumbra and core threshold was determined as the brain coverage was gradually reduced from 160 mm to 20 mm. The Wilcoxon signed-rank test, concordance correlation coefficient (CCC), and analysis of variance were used for the first, second, and third steps, respectively. Results CT perfusion at penumbra and core thresholds resulted in the least volumetric difference from MR imaging reference values with delay times greater than 3 seconds and delay-corrected cerebral blood flow of less than 30% (P = .34 and .33, respectively). When the thresholds were applied to the new group of patients, prediction of the final infarction was allowed with delay times greater than 3 seconds in patients with no recanalization of the occluded artery (CCC, 0.96 [95% confidence interval: 0.92, 0.98]) and with delay-corrected cerebral blood flow less than 30% in patients with complete recanalization (CCC, 0.91 [95% confidence interval: 0.83, 0.95]). However, the ischemic volume with a delay time greater than 3 seconds was underestimated when the brain coverage was reduced to 80 mm (P = .04) and the core volume measured as cerebral blood flow less than 30% was

  4. Dual-energy perfusion-CT in recurrent pancreatic cancer. Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, F.; Skornitzke, S.; Kauczor, H.U.; Stiller, W.; Klauss, M. [Heidelberg Univ. (Germany). Clinic of Diagnostic and Interventional Radiology; Hackert, T. [Heidelberg Univ. (Germany). Clinic of Surgery; Grenacher, L. [Diagnostik Muenchen (Germany). Diagnostic Imaging Center

    2016-06-15

    To evaluate the diagnostic performance of dual energy (DE) perfusion-CT for the differentiation between postoperative soft-tissue formation and tumor recurrence in patients after potentially curative pancreatic cancer resection. 24 patients with postoperative soft-tissue formation in the conventional regular follow-up CT acquisition after pancreatic cancer resection with curative intent were included prospectively. They were examined with a 64-row dual-source CT using a dynamic sequence of 34 DE acquisitions every 1.5 s (80 ml of iodinated contrast material, 370 mg/ml, flow rate 5 ml/s). Weighted average (linearly blended M0.5) 120 kVp-equivalent dual-energy perfusion image data sets were evaluated with a body-perfusion CT tool for estimating blood flow, permeability, and blood volume. Diagnosis was confirmed by histological study (n=4) and by regular follow-up. Final diagnosis was local recurrence of pancreatic cancer in 15 patients and unspecific postoperative tissue formation in 9 patients. The blood-flow values for recurrence tissue trended to be lower compared to postoperative tissue formation with 16.6 ml/100 ml/min and 24.7 ml/100 ml/min, respectively for weighted average 120 kVp-equivalent image data, which was not significant (n.s.) (p=0.06, significance level 0.05). Permeability- and blood-volume values were only slightly lower in recurrence tissue (n.s.). DE perfusion-CT is feasible in patients after pancreatic cancer resection and a promising functional imaging technique. As only a trend for lower perfusion values in local recurrence compared to unspecific postoperative alterations was found, the perfusion differences are not yet sufficient to differentiate between malignancy and unspecific postoperative alterations for this new technique. Further studies and technical improvements are needed to generate reliable data for this clinically highly relevant differentiation.

  5. CT of diffuse pulmonary diseases

    International Nuclear Information System (INIS)

    Itoh, Harumi; Murata, Kiyoshi; Todo, Giro

    1987-01-01

    While the theory of chest radiographic interpretation in diagnosing diffuse pulmonary diseases has not yet been established, X-ray computed tomography (CT), having intrinsic high contrast resolution and improved spatial resolution, has proved to offer important imformation concerning the location and invasion of diffuse pulmonary lesions. This study related to CT-pathologic correlation, focusing on perivascular interstitial space and secondary pulmonary lobule at macroscopic levels. The perivascular interstitial space was thickened as a result of the infiltration of cancer, granulomas, and inflammatory cells. This finding appeared as irregular contour of the blood vessel on CT. Centrilobular nodules were distributed at the tip of the bronchus or pulmonary artery on CT. The distance from the terminal and respiratory bronchioles to the lobular border was 2 to 3 mm. Lobular lesions were delineated as clear margin on CT. Contribution of these CT features to chest radiographic interpretation must await further studies. (Namekawa, K.)

  6. Appearance and impact of post-operative intracranial clips and coils on whole-brain CT angiography and perfusion

    International Nuclear Information System (INIS)

    Roach, Cayce J.; Russell, Cheryl L.; Hanson, Eric H.; Bluett, Brent; Orrison, William W.

    2012-01-01

    Background: To evaluate the effect of vascular clips and endovascular coils placed for intracranial aneurysms and arteriovenous malformations on whole-brain computed tomography (CT) angiography and perfusion. Methods: A 320-detector row dynamic volume CT system imaged 11 patients following surgical placement of vascular clips or endovascular coils. The extent of clip and coil subtraction by automated software was evaluated using CT digital subtraction angiography and CT perfusion. Impact on CT perfusion values by retained intracranial devices was compared to age- and gender-matched controls. Results: Clip and coil subtraction on CT angiography was graded as good in 8 and moderate in 3 cases. A residual neck and additional aneurysm were noted in 1 of 11 patients. Post-procedural axial slice level CT perfusion values decreased in reliability with increasing proximity to the metallic devices secondary to beam hardening. However, the intracranial devices did not affect axial slice level CTP values of cerebral blood volume, cerebral blood flow and mean transit time outside of the level of the device. Time to peak values was globally decreased outside of the immediate vascular intervention region. Conclusions: Advances in CT technology have provided clinically useful subtraction of intracranial clips and coils. While CT perfusion values were altered in device subtraction areas and within beam hardening artifact areas; they can provide valuable postoperative information on whole-brain hemodynamics. In selected cases, the combination of CT angiography and whole-brain CT perfusion can offer an alternative to conventional angiography that is a more invasive option.

  7. Comparison of stroke infarction between CT perfusion and diffusion weighted imaging: preliminary results

    Science.gov (United States)

    Abd. Rahni, Ashrani Aizzuddin; Arka, Israna Hossain; Chellappan, Kalaivani; Mukari, Shahizon Azura; Law, Zhe Kang; Sahathevan, Ramesh

    2016-03-01

    In this paper we present preliminary results of comparison of automatic segmentations of the infarct core, between that obtained from CT perfusion (based on time to peak parameter) and diffusion weighted imaging (DWI). For each patient, the two imaging volumes were automatically co-registered to a common frame of reference based on an acquired CT angiography image. The accuracy of image registration is measured by the overlap of the segmented brain from both images (CT perfusion and DWI), measured within their common field of view. Due to the limitations of the study, DWI was acquired as a follow up scan up to a week after initial CT based imaging. However, we found significant overlap of the segmented brain (Jaccard indices of approximately 0.8) and the percentage of infarcted brain tissue from the two modalities were still fairly highly correlated (correlation coefficient of approximately 0.9). The results are promising with more data needed in future for clinical inference.

  8. A 4D CT digital phantom of an individual human brain for perfusion analysis

    Science.gov (United States)

    Brune, Christoph; van Ginneken, Bram; Prokop, Mathias

    2016-01-01

    Brain perfusion is of key importance to assess brain function. Modern CT scanners can acquire perfusion maps of the cerebral parenchyma in vivo at submillimeter resolution. These perfusion maps give insights into the hemodynamics of the cerebral parenchyma and are critical for example for treatment decisions in acute stroke. However, the relations between acquisition parameters, tissue attenuation curves, and perfusion values are still poorly understood and cannot be unraveled by studies involving humans because of ethical concerns. We present a 4D CT digital phantom specific for an individual human brain to analyze these relations in a bottom-up fashion. Validation of the signal and noise components was based on 1,000 phantom simulations of 20 patient imaging data. This framework was applied to quantitatively assess the relation between radiation dose and perfusion values, and to quantify the signal-to-noise ratios of penumbra regions with decreasing sizes in white and gray matter. This is the first 4D CT digital phantom that enables to address clinical questions without having to expose the patient to additional radiation dose. PMID:27917312

  9. Study on 64-multidetector-row CT perfusion imaging of lung cancer

    International Nuclear Information System (INIS)

    Kang Jianghe; Liang Kunru; Duan Shaoyin; Huang Yimin; Lv Shaomao

    2009-01-01

    Objective: To evaluate the characteristics of 64-multidetector-row CT perfusion imaging in lung cancer. Methods: 64-multidetector-row CT perfusion was performed in 60 patients with lung cancer (adenocarcinoma in 35 cases, squamous cell carcinoma in 11 cases, small cell carcinoma in 8 cases, metastatic carcinoma in 6 cases). The volume of tumors was 3.56-115.68cm 3 . The parameters of CT perfusion were compared by pathologic types and volume of tumors, including blood flow (BF), blood volume (BV), mean transit time (MTT), permeability surface (PS), time density curve (TDC) and peak enhancement (PE). GE VCT 64-multidetector-row CT was used in 60 cases, with cine mode of 2.5-5mm/8 slices. Scan time was 40 second. Analyzing software was CT perfusion-3. Results: The first-phase of contrast medium flew through aorta were 14-28s (mean value was 198s). There were significant differences of BV and BF value among pathologic types of lung cancer, and the outcome was as follow: squamous cell carcinoma > metastatic carcinoma > adenocarcinoma> small cell carcinoma. There were no statistical significances of MTT and PS values among different pathologic types. CT value of tumors in plain scan in metastatic carcinoma was significantly greater than in other pathologic types. There were significant differences of PE value in small cell carcinoma and metastatic carcinoma. No statistically differences between different volumes of tumors with regard to the parameters of perfusion imaging. The peak time of TDC located in the area of aorta peak time, of which 8 cases with type A and 52 cases with types B, and 4 cases (4/6,50%)of metastatic carcinoma with types A. Conclusion: There is correlation between BV value, BF value and pathologic types, but no significant correlation of different volume of tumors. TDC of metastatic carcinoma mainly present as type A. (authors)

  10. Feasibility of Flat Panel Detector CT in Perfusion Assessment of Brain Arteriovenous Malformations: Initial Clinical Experience.

    Science.gov (United States)

    Garcia, M; Okell, T W; Gloor, M; Chappell, M A; Jezzard, P; Bieri, O; Byrne, J V

    2017-04-01

    The different results from flat panel detector CT in various pathologies have provoked some discussion. Our aim was to assess the role of flat panel detector CT in brain arteriovenous malformations, which has not yet been assessed. Five patients with brain arteriovenous malformations were studied with flat panel detector CT, DSC-MR imaging, and vessel-encoded pseudocontinuous arterial spin-labeling. In glomerular brain arteriovenous malformations, perfusion was highest next to the brain arteriovenous malformation with decreasing values with increasing distance from the lesion. An inverse tendency was observed in the proliferative brain arteriovenous malformation. Flat panel detector CT, originally thought to measure blood volume, correlated more closely with arterial spin-labeling-CBF and DSC-CBF than with DSC-CBV. We conclude that flat panel detector CT perfusion depends on the time point chosen for data collection, which is triggered too early in these patients (ie, when contrast agent appears in the superior sagittal sinus after rapid shunting through the brain arteriovenous malformation). This finding, in combination with high data variability, makes flat panel detector CT inappropriate for perfusion assessment in brain arteriovenous malformations. © 2017 by American Journal of Neuroradiology.

  11. Evaluation of anterior mediastinal solid tumors by CT perfusion: a preliminary study.

    Science.gov (United States)

    Bakan, Selim; Kandemirli, Sedat Giray; Dikici, Atilla Süleyman; Erşen, Ezel; Yıldırım, Onur; Samancı, Cesur; Batur, Şebnem; Çebi Olgun, Deniz; Kantarcı, Fatih; Akman, Canan

    2017-01-01

    We aimed to assess the role of computed tomography (CT) perfusion in differentiation of thymoma from thymic hyperplasia, lymphoma, thymic carcinoma, and lung cancer invading anterior mediastinum. In this study, 25 patients with an anterior mediastinal lesion underwent CT perfusion imaging from January 2015 to February 2016. Diagnoses included thymoma (n=7), thymic hyperplasia (n=8), lymphoma (n=4), thymic carcinoma (n=3), and invasive lung cancer (n=3). Lymphoma, thymic carcinoma, and lung cancer were grouped as malignant tumors for statistical analysis. Values for blood flow, blood volume, and permeability surface were measured in CT perfusion. Blood flow and blood volume values were higher in thymoma in comparison to thymic hyperplasia; however, the difference was not statistically significant. Blood volume values were significantly higher in thymoma (mean, 11.4 mL/100 mL; range, 5.2-20.2 mL/100 mL) compared with lymphoma (mean, 5.3 mL/100 mL; range, 2.5-7.2 mL/100 mL) (P = 0.023). Blood flow and blood volume values were significantly higher in thymoma compared with non-thymoma malignant tumors (P = 0.025). CT perfusion is helpful in differentiating thymoma from non-thymoma malignancies including lymphoma, thymic carcinoma, and invasive lung cancer involving the anterior mediastinum.

  12. Renal hemodynamic changes with aging: a preliminary study using CT perfusion in the healthy elderly.

    Science.gov (United States)

    Zhao, Hong; Gong, Jingshan; Wang, Yan; Zhang, Zuoquan; Qin, Peixin

    2010-01-01

    To investigate renal blood flow perfusion parameter changes associated with aging using multislice spiral computed tomography (CT). This prospective study was approved by the institute's ethics committee for clinical study and written informed consent was obtained from all subjects. Forty-two consecutive patients who underwent abdominal CT without obvious renal abnormality at plain scanning were enrolled in this study. The renal perfusion scan was carried out using 16-slice spiral CT. The Pearson correlation coefficient was used to examine the correlation between perfusion parameter changes with aging. In both the cortex and medulla, blood flow (BF) and blood volume (BV) were negatively correlated with age, while time-to-peak (TTP) value and mean transit time (MTT) showed a positive correlation with age. Changes in BF, TTP, and MTT were found to have a statistically significant correlation with age in both the cortex and medulla, while the correlation between BV and age showed no statistical significance. It is feasible to assess renal hemodynamics changes with aging in the elderly using the current clinically available CT perfusion imaging technology in vivo. It may be helpful in the management of aged patients to familiarize with the renal hemodynamics changes in clinical work-up. Copyright 2010 Elsevier Inc. All rights reserved.

  13. Kombineret ventilations/perfusions-SPECT/CT er bedst til diagnostik af lungeemboli

    DEFF Research Database (Denmark)

    Gutte Borgwardt, Henrik; Mortensen, Jann; Kristoffersen, Ulrik Sloth

    2012-01-01

    and very limited data comparing these modalities are available. With the use of hybrid scanners, ventilation/perfusion-single-photon-emission-tomography (V/Q-SPECT) in combination with low-dose CT without contrast enhancement is feasible and should probably be considered first-line imaging in diagnosing PE....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-10-15

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

  15. Studies on blood supply of liver metastasis with DSA, CT and portal vein perfusion CT during superior mesenteric arterial portography

    International Nuclear Information System (INIS)

    Li Zhigang; Shi Gaofeng; Huang Jingxiang; Li Shunzong; Liang Guoqing; Wang Hongguang; Han Pengyin; Wang Qi; Gu Tieshu

    2008-01-01

    Objective: To probe the blood supply of liver metastasis by celiac artery, proper hepatic artery DSA, portal vein perfusion CT during superior mesenteric arterial portography (PCTAP). Methods: One hundred patients with liver metastases were examined prospectively by plain CT scan, multiphase enhanced CT scan, celiac arteriography and proper hepatic arteriography. Of them, 56 patients were examined by PCTAP. All primary lesions were confirmed by operation and (or) pathology examination. In order to investigate the blood supply of metastasis lesions, the software of Photoshop was used to obtain the time-attenuation curves (TDC) of tumor center, tumor edge, portal vein and normal liver parenchyma adjacent to the tumor to calculate liver perfusion for DSA image analysis, while a deconvolution model from CT perfusion software was designed for the dual blood supply. Results: DSA findings: TDC of proper hepatic arteriography showed: the mean peak concentration (K value) in tumor centers was (67 ± 12)%, and it was (76 ± 15)% for peritumor tissue, (51 ± 10)% in normal liver parenchyma. TDC of celiac arteriogaphy showed that the contrast concentration of tumor centers and tumor edge increased fast in early stage, then maintained a slight upward plateau, in the meanwhile, the contrast concentration of normal liver parenchyma kept increasing slowly. PCTAP findings: tumors exhibited no enhancement during 30 s continued scans. Conclusion: The blood supply of liver metastasis mainly comes from hepatic artery, but barely from portal vein. (authors)

  16. Correlation between serum VEGF level and CT perfusion imaging in patients with primary liver cancer pre-and post TACE

    International Nuclear Information System (INIS)

    Jia Zhongzhi; Huang Yuanquan; Feng Yaoliang; Shi Haibin

    2010-01-01

    Objective: To investigate the correlation between serum vascular endothelial growth factor(VEGF) level and CT perfusion parameters in patients with primary liver cancer (PLC) pre-and post-transcatheter arterial chemoembolization (TACE) treatment. Methods: Serum VEGF level was measured and CT perfusion imaging was performed 1 day before and 6 ∼ 8, 32 ∼ 40 days after TACE in 18 patients with PLC. Before and after TACE, the serum VEGF level, the tumor's artery liver perfusion (ALP), the portal vein perfusion (PVP) and the hepatic artery perfusion index (HPI) were measured pre-and post-TACE. The pre-TACE and post-TACE results were compared and statistically analyzed. Results: Based on the therapeutic results, the patients were divided into complete response (CR) group and partial response or stable disease(PR+SD) group. Although no significant difference in serum VEGF level, tumor's ALP, PVP and HPI existed between two groups pre-TACE, there was significant difference in ALP, HPI 6-8 days after TACE (P<0.05). Significant difference in serum VEGF level also existed in CR group (P<0.05), but not in (PR+SD) group, at (32-40) days post-TACE (P=0.221). The serum VEGF level carried a positive correlation with the tumor's ALP and HPI. Conclusion: The serum VEGF level can indirectly reflect the neovascularization of the tumor, while the CTPI can directly and quantitatively reflect the hemodynamic changes of the tumor post-TACE. Moreover, a positive correlation exists between serum VEGF level and ALP, HPI. Therefore, the determination of serum VEGF level together with CTPI is very useful in both evaluating TACE efficacy and making therapeutic schedule. (authors)

  17. CT perfusion imaging of the liver and the spleen in patients with cirrhosis: Is there a correlation between perfusion and portal venous hypertension?

    Energy Technology Data Exchange (ETDEWEB)

    Talakic, Emina; Schoellnast, Helmut [Medical University of Graz, Division of General Radiology, Department of Radiology, Graz (Austria); Schaffellner, Silvia; Kniepeiss, Daniela; Mueller, Helmut [Medical University of Graz, Department of Surgery, Division of Transplantation Surgery, Graz (Austria); Stauber, Rudolf [Medical University of Graz, Department of Internal Medicine, Division of Gastoenterology and Hepatology, Graz (Austria); Quehenberger, Franz [Medical University of Graz, Institute for Medical Informatics, Statistics and Documentation, Graz (Austria)

    2017-10-15

    To correlate hepatic and splenic CT perfusion parameters with hepatic venous pressure gradient (HVPG) measurements in patients with cirrhosis. Twenty-one patients with cirrhosis (males, 17; females, 4; mean ± SD age, 57 ± 7 years) underwent hepatic and splenic perfusion CT on a 320-detector row volume scanner as well as invasive measurement of HVPG. Different CT perfusion algorithms (maximum slope analysis and Patlak plot) were used to measure hepatic arterial flow (HAF), portal venous flow (PVF), hepatic perfusion index (HPI), splenic arterial flow (SAF), splenic blood volume (SBV) and splenic clearance (SCL). Hepatic and splenic perfusion parameters were correlated with HVPG, and sensitivity and specificity for detection of severe portal hypertension (≥12 mmHg) were calculated. The Spearman correlation coefficient was -0.53 (p < 0.05) between SAF and HVPG, and -0.68 (p < 0.01) between HVPG and SCL. Using a cut-off value of 125 ml/min/100 ml for SCL, sensitivity for detection of a HVPG of ≥12 mmHg was 94%, and specificity 100%. There was no significant correlation between hepatic perfusion parameters and HVPG. CT perfusion in patients with cirrhosis showed a strong correlation between SCL and HVPG and may be used for detection of severe portal hypertension. (orig.)

  18. CT perfusion imaging of the liver and the spleen in patients with cirrhosis: Is there a correlation between perfusion and portal venous hypertension?

    Science.gov (United States)

    Talakić, Emina; Schaffellner, Silvia; Kniepeiss, Daniela; Mueller, Helmut; Stauber, Rudolf; Quehenberger, Franz; Schoellnast, Helmut

    2017-10-01

    To correlate hepatic and splenic CT perfusion parameters with hepatic venous pressure gradient (HVPG) measurements in patients with cirrhosis. Twenty-one patients with cirrhosis (males, 17; females, 4; mean ± SD age, 57 ± 7 years) underwent hepatic and splenic perfusion CT on a 320-detector row volume scanner as well as invasive measurement of HVPG. Different CT perfusion algorithms (maximum slope analysis and Patlak plot) were used to measure hepatic arterial flow (HAF), portal venous flow (PVF), hepatic perfusion index (HPI), splenic arterial flow (SAF), splenic blood volume (SBV) and splenic clearance (SCL). Hepatic and splenic perfusion parameters were correlated with HVPG, and sensitivity and specificity for detection of severe portal hypertension (≥12 mmHg) were calculated. The Spearman correlation coefficient was -0.53 (p perfusion parameters and HVPG. CT perfusion in patients with cirrhosis showed a strong correlation between SCL and HVPG and may be used for detection of severe portal hypertension. • SAF and SCL are statistically significantly correlated with HVPG • SCL showed stronger correlation with HVPG than SAF • 125 ml/min/100 ml SCL-cut-off yielded 94 % sensitivity, 100 % specificity for severe PH • HAF, PVF and HPI showed no statistically significant correlation with HVPG.

  19. A non-linear regression method for CT brain perfusion analysis

    Science.gov (United States)

    Bennink, E.; Oosterbroek, J.; Viergever, M. A.; Velthuis, B. K.; de Jong, H. W. A. M.

    2015-03-01

    CT perfusion (CTP) imaging allows for rapid diagnosis of ischemic stroke. Generation of perfusion maps from CTP data usually involves deconvolution algorithms providing estimates for the impulse response function in the tissue. We propose the use of a fast non-linear regression (NLR) method that we postulate has similar performance to the current academic state-of-art method (bSVD), but that has some important advantages, including the estimation of vascular permeability, improved robustness to tracer-delay, and very few tuning parameters, that are all important in stroke assessment. The aim of this study is to evaluate the fast NLR method against bSVD and a commercial clinical state-of-art method. The three methods were tested against a published digital perfusion phantom earlier used to illustrate the superiority of bSVD. In addition, the NLR and clinical methods were also tested against bSVD on 20 clinical scans. Pearson correlation coefficients were calculated for each of the tested methods. All three methods showed high correlation coefficients (>0.9) with the ground truth in the phantom. With respect to the clinical scans, the NLR perfusion maps showed higher correlation with bSVD than the perfusion maps from the clinical method. Furthermore, the perfusion maps showed that the fast NLR estimates are robust to tracer-delay. In conclusion, the proposed fast NLR method provides a simple and flexible way of estimating perfusion parameters from CT perfusion scans, with high correlation coefficients. This suggests that it could be a better alternative to the current clinical and academic state-of-art methods.

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

    Directory of Open Access Journals (Sweden)

    Jiang-Xia Lei

    2016-10-01

    Full Text Available 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 and survivin in pancreatic cancer tissue samples were higher than those in paracarcinoma tissue samples, and mRNA expression levels of P53 and Bax 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 of Bcl-2, Bcl-xL and survivin in pancreatic cancer tissue, and positively correlated with mRNA expression levels of P53 and Bax in 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

  1. Automatic Valve Plane Localization in Myocardial Perfusion SPECT/CT by Machine Learning: Anatomic and Clinical Validation.

    Science.gov (United States)

    Betancur, Julian; Rubeaux, Mathieu; Fuchs, Tobias A; Otaki, Yuka; Arnson, Yoav; Slipczuk, Leandro; Benz, Dominik C; Germano, Guido; Dey, Damini; Lin, Chih-Jen; Berman, Daniel S; Kaufmann, Philipp A; Slomka, Piotr J

    2017-06-01

    Precise definition of the mitral valve plane (VP) during segmentation of the left ventricle for SPECT myocardial perfusion imaging (MPI) quantification often requires manual adjustment, which affects the quantification of perfusion. We developed a machine learning approach using support vector machines (SVM) for automatic VP placement. Methods: A total of 392 consecutive patients undergoing 99m Tc-tetrofosmin stress (5 min; mean ± SD, 350 ± 54 MBq) and rest (5 min; 1,024 ± 153 MBq) fast SPECT MPI attenuation corrected (AC) by CT and same-day coronary CT angiography were studied; included in the 392 patients were 48 patients who underwent invasive coronary angiography and had no known coronary artery disease. The left ventricle was segmented with standard clinical software (quantitative perfusion SPECT) by 2 experts, adjusting the VP if needed. Two-class SVM models were computed from the expert placements with 10-fold cross validation to separate the patients used for training and those used for validation. SVM probability estimates were used to compute the best VP position. Automatic VP localizations on AC and non-AC images were compared with expert placement on coronary CT angiography. Stress and rest total perfusion deficits and detection of per-vessel obstructive stenosis by invasive coronary angiography were also compared. Results: Bland-Altman 95% confidence intervals (CIs) for VP localization by SVM and experts for AC stress images (bias, 1; 95% CI, -5 to 7 mm) and AC rest images (bias, 1; 95% CI, -7 to 10 mm) were narrower than interexpert 95% CIs for AC stress images (bias, 0; 95% CI, -8 to 8 mm) and AC rest images (bias, 0; 95% CI, -10 to 10 mm) ( P learning with SVM allows automatic and accurate VP localization, decreasing user dependence in SPECT MPI quantification. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

  2. Validation of regional myocardial perfusion with cine CT

    International Nuclear Information System (INIS)

    Gould, R.G.; McNamara, T.; Koshold, S.; Lipton, M.; Sievers, R.; Higgins, C.B.; Boyd, D.

    1986-01-01

    Blood flow within each of eight quadrants of the myocardium was measured in dogs using a cine-CT scanner and also with microspheres. Cine-CT flow measurements were made using a nonionic contrast agent and flow was calculated by a formula that used both the maximum iodine concentration and the peak delay time. Measurements were obtained at rest and during hyperperfusion induced by chromonar. Simultaneous cine-CT and microsphere measurements correlated (slope = 0.71 r = .8) over a range of 0.4-7.0 ml/min/g

  3. Correlation between CT perfusion parameters and Fuhrman grade in pTlb renal cell carcinoma.

    Science.gov (United States)

    Chen, Chao; Kang, Qinqin; Wei, Qiang; Xu, Bing; Ye, Hui; Wang, Tiegong; Lu, Yayun; Lu, Jianping

    2017-05-01

    To evaluate the correlation of CT perfusion parameters with the Fuhrman grade in pT1b (4-7 cm) renal cell carcinoma (RCC). CT perfusion imaging and Fuhrman pathological grading of pT1b RCC were performed in 48 patients (10 grade 1, 27 grade 2, 9 grade 3, and 2 grade 4). Equivalent blood volume (BV Equiv ), permeability surface area product (PS), and blood flow (BF) of tumors were measured. Grade 1 and 2 were defined as low-grade group (n = 37), meanwhile high-grade group (n = 11) included grade 3 and 4. Comparisons of CT perfusion parameters and tumor size of the two different groups were performed. Correlations between CT perfusion parameters, Fuhrman grade (grade 1, 2, 3, and 4), and tumor size were assessed. PS was significantly lower in high grade than in low-grade pT1b RCC (P = 0.004). However, no significant differences were found in BV Equiv and BF between the two groups (P > 0.05 for both). The optimal threshold value, sensitivity, specificity, and the area under the ROC curve for distinguishing the two groups using PS were 68.8 mL/100 g/min, 0.7, 0.8, and 0.8, respectively. Negative significant correlation was observed between PS and Fuhrman grade (r = -0.338, P = 0.019). The PS of pT1b RCC had negative significant correlation with Fuhrman grade. CT perfusion appeared to be a non-invasive means to predict high Fuhrman grade of pT1b RCC preoperatively and guide the optimal treatment for the patient.

  4. SPECTCT cerebral perfusion scintigraphy; is the low-dose CT component of diagnostic value?

    Energy Technology Data Exchange (ETDEWEB)

    Sulkin, T.V.C. [Department of Clinical Imaging, Royal Cornwall Hospital, Truro, Cornwall (United Kingdom)], E-mail: tom.sulkin@rcht.cornwall.nhs.uk; Cousens, C. [Department of Clinical Imaging, Royal Cornwall Hospital, Truro, Cornwall (United Kingdom)

    2008-03-15

    Aim: To assess the potential diagnostic value of the low-dose computed tomography (CT) component of dual-examination single photon emission CT and CT (SPECTCT) cerebral perfusion studies. Method and materials: Two hundred and forty consecutive 99 mTc hexamethylpropylene amine oxime (HMPAO) SPECTCT studies were considered for inclusion. The images were acquired on a hybrid dual-head gamma camera/low-dose CT system. The CT component had a fixed tube current of 2.5 mA. The CT section thickness was 5 mm and total acquisition time approximately 7.5 min. Studies in which no CT images were acquired, or those excessively degraded by movement artefact were excluded. The CT images of each of the remaining studies were retrospectively reviewed and categorized as normal or abnormal. Details of the abnormalities were recorded. Results: Fifteen of the 240 studies were excluded as no CT images were obtained. A further 14 were excluded as they were considered excessively degraded by movement artefact. A single abnormality was demonstrated on 48 (23%), and two abnormalities on four (2%) of the remaining 211 studies. The most common abnormal findings were low attenuation in the deep cortical white matter (n = 22), infarcts (n = 12), cerebral atrophy (n = 7), dilated ventricles (n = 5), basal ganglia calcification (n = 4), and post-surgical change (n = 3). Other findings included a chronic subdural haematoma, a meningioma, and a posterior fossa cyst. Previous cerebral imaging was available for comparison in 31% of cases. There was 85% concordance between previous imaging and the low-dose CT images. Conclusion: Twenty-five percent of the low-dose CT images in this study demonstrated abnormalities. Therefore the CT component of cerebral perfusion SPECTCT investigations should be routinely reported in their own right.

  5. Characteristics of CT Perfusion Parameters of Focal Pancreatic Lesions and Data Comparison of Different Algorithms.

    Science.gov (United States)

    Li, Ping; Zhu, Liang; Xue, Huadan; Liu, Changyi; Xu, Kai; Li, Juan; Sun, Ting; Jin, Zhengyu

    2017-02-20

    Objective To characterize the CT perfusion parameters of focal pancreatic lesions including pancreatic cancers (PACs) and pancreatic neuroendocrine tumors (pNETs),estimate the confirmity and fungibility of parameters obtained from Deconvolution and Maximum slope+Patlak.Methods From December 2015 to November 2016,22 patients with PACs and 22 patients with pNETs(37 lesions confirmed by surgery and biopsy)underwent preoperative whole-pancreas CT perfusion in our center. The volume perfusion CT of the entire pancreas was performed at 80 kV and 100 mA,using 28 consecutive volume measurements and intravenous injection of 45 ml of iodinated contrast and saline at a flow rate of 5 ml/s. One experienced radiologists measured and recorded the CT perfusion parameters on Siemens post-processing workstation using two mathematical methods:Maximum slope+Patlak analysis versus Deconvolution method.ResultsWilcoxon matched-pairs test revealed significant difference between both pairs of the perfusion measurements by the two methods,PACs(BFM vs. BFD,Z=-3.263,P=0.001;BVD vs. BVP,Z=-3.978,P=0.000); pNETs(BFM vs. BFD,Z=-5.212,P=0.000;BVD vs. BVP,Z=-2.633,P=0.008). Spearman's correlation coefficient showed both pairs of perfusion measurements significantly correlated with each other in PACs (BFM vs. BFD,r=0.845,P=0.000;BVD vs. BVP,r=0.964,P=0.000) and pNETs(BFM vs. BFD,r=0.759,P=0.000),BVD vs. BVP,r=0.683,P=0.000). Geometric mean BFM/BFD ratio in PACs was 0.77 (range:0.61-0.99),while geometric mean BVD/BVP ratio was 1.42 (range:1.13-1.79),within 95% limits of agreement. Geometric mean BFM/BFD ratio in pNETs was 0.66 (range:0.51-0.86),while geometric mean BVD/BVP ratio was 1.15 (range:0.88-1.50),within 95% limits of agreement. Conclusion sSignificantly different CT perfusion values of blood flow and blood volume were obtained by Deconvolution-based and Maximum slope+Patlak-based algorithms in the pNETs and PACs. They correlated significantly with each other. Two perfusion

  6. Perfusion CT assessment of the colon and rectum: Feasibility of quantification of bowel wall perfusion and vascularization

    International Nuclear Information System (INIS)

    Khan, Sairah; Goh, Vicky; Tam, Emily; Wellsted, David; Halligan, Steve

    2012-01-01

    The aim was to determine the feasibility of vascular quantification of the bowel wall for different anatomical segments of the colorectum. Following institutional ethical approval and informed consent, 39 patients with colorectal cancer underwent perfusion CT. Blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface area product (PS) were assessed for different segments of the colorectum: ascending, transverse, descending colon, sigmoid, or rectum, that were distant from the tumor, and which were proven normal on contemporary colonoscopy, and subsequent imaging and clinical follow up. Mean (SD) for BF, BV, MTT and PS for the different anatomical colorectal segments were obtained and compared using a pooled t-test. Significance was at 5%. Assessment was not possible in 9 of 39 (23%) patients as the bowel wall was ≤5 mm precluding quantitative analysis. Forty-four segments were evaluated in the remaining 30 patients. Mean BF was higher in the proximal than distal colon: 24.0 versus 17.8 mL/min/100 g tissue; p = 0.009; BV, MTT and PS were not significantly different; BV: 3.46 versus 3.15 mL/100 g tissue, p = 0.45; MTT: 15.1 versus 18.3 s; p = 0.10; PS: 6.84 versus 8.97 mL/min/100 tissue, p = 0.13, respectively. In conclusion, assessment of bowel wall perfusion may fail in 23% of patients. The colorectum demonstrates segmental differences in perfusion.

  7. Application of dual-source CT perfusion imaging and MRI for the diagnosis of primary liver cancer.

    Science.gov (United States)

    Zhang, Dongwen; Xu, Aixia

    2017-11-01

    The objective of the present study was to evaluate the application of dual-source CT perfusion imaging and MRI for the diagnosis of primary liver cancer. Sixty-three patients with primary liver cancer were selected between February 2015 and May 2016. All patients underwent examinations by dual-source CT perfusion imaging and MRI. The perfusion parameters of the focus center and normal liver parenchyma by CT examination and the hemodynamic parameters of the focus center and normal liver parenchyma by MRI examination were analyzed. The accuracy rates of the three detection methods (CT perfusion imaging, MRI, and combined examination) were analyzed and compared by ROC curves. Dual-source CT perfusion imaging revealed that blood flow and blood volume of the focus center were significantly higher than those of normal liver parenchyma (Pperfusion and hepatic perfusion index of the focus center were significantly higher than those of normal liver parenchyma; portal venous perfusion of the focus center was significantly lower than that of normal liver parenchyma (Pperfusion between the focus center and normal liver parenchyma was not significant (P>0.05); the accuracy rates of CT perfusion imaging, MRI, and combined examination were 76.19, 85.71, and 95.24% respectively; the area under the curve of CT perfusion imaging was 0.753 (PCT combined with MRI was 0.947 (PCT perfusion imaging combined with MRI for examination of primary liver cancer is superior to that of single use of CT or MRI, and has high clinical application and popularization value.

  8. Brain volume perfusion CT performed with 128-detector row CT system in patients with cerebral gliomas: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Xyda, Argyro [University Hospital of Goettingen, Department of Neuroradiology, Georg-August University, Goettingen (Germany); University Hospital of Heraklion, Department of Radiology, Crete (Greece); Haberland, Ulrike; Klotz, Ernst [Computed Tomography, Siemens AG Healthcare Sector, Forchheim (Germany); Bock, Hans Christoph [University Hospital of Goettingen, Department of Neurosurgery, Georg-August University, Goettingen (Germany); Jung, Klaus [University Hospital of Goettingen, Department of Medical Statistics, Georg-August University, Goettingen (Germany); Knauth, Michael; Schramm, Ramona; Psychogios, Marios Nikos; Schramm, Peter [University Hospital of Goettingen, Department of Neuroradiology, Georg-August University, Goettingen (Germany); Erb, Gunter [Bracco Imaging Deutschland GmbH, Konstanz (Germany)

    2011-09-15

    Validation of the feasibility and efficacy of volume perfusion computed tomography (VPCT) in the preoperative assessment of cerebral gliomas by applying a 128-slice CT covering the entire tumour. Forty-six patients (25 men, 21 women; mean age 52.8 years) with cerebral gliomas were evaluated with VPCT. Two readers independently evaluated VPCT data, drawing volumes of interest (VOIs) around the tumour according to maximum intensity projection volumes, which were mapped automatically onto the cerebral blood volume (CBV), flow (CBF) and permeability (Ktrans) perfusion datasets. As control, a second VOI was placed in the contralateral healthy cortex. Correlation among perfusion parameters, tumour grade, hemisphere and VOIs was assessed. The diagnostic power of perfusion parameters was analysed by receiver operating characteristics curve analyses. VPCT was feasible in the assessment of the entire tumour extent. Mean values of Ktrans, CBV, CBF in high-grade gliomas were significantly higher compared with low-grade (p < 0.01). Ktrans demonstrated the highest diagnostic (97% sensitivity), positive (100%) and negative (94%) prognostic values. VPCT was feasible in all subjects. All areas of different perfusion characteristics are depicted and quantified in colour-coded 3D maps. The derived parameters correlate well with tumour histopathology, differentiating low- from high-grade gliomas. (orig.)

  9. Effects of radiation dose reduction in Volume Perfusion CT imaging of acute ischemic stroke.

    Science.gov (United States)

    Othman, Ahmed E; Brockmann, Carolin; Yang, Zepa; Kim, Changwon; Afat, Saif; Pjontek, Rastislav; Nikobashman, Omid; Brockmann, Marc A; Kim, Jong Hyo; Wiesmann, Martin

    2015-12-01

    To examine the influence of radiation dose reduction on image quality and sensitivity of Volume Perfusion CT (VPCT) maps regarding the detection of ischemic brain lesions. VPCT data of 20 patients with suspected ischemic stroke acquired at 80 kV and 180 mAs were included. Using realistic reduced-dose simulation, low-dose VPCT datasets with 144 mAs, 108 mAs, 72 mAs and 36 mAs (80 %, 60 %, 40 % and 20 % of the original levels) were generated, resulting in a total of 100 datasets. Perfusion maps were created and signal-to-noise-ratio (SNR) measurements were performed. Qualitative analyses were conducted by two blinded readers, who also assessed the presence/absence of ischemic lesions and scored CBV and CBF maps using a modified ASPECTS-score. SNR of all low-dose datasets were significantly lower than those of the original datasets (p < .05). All datasets down to 72 mAs (40 %) yielded sufficient image quality and high sensitivity with excellent inter-observer-agreements, whereas 36 mAs datasets (20 %) yielded poor image quality in 15 % of the cases with lower sensitivity and inter-observer-agreements. Low-dose VPCT using decreased tube currents down to 72 mAs (40 % of original radiation dose) produces sufficient perfusion maps for the detection of ischemic brain lesions. • Perfusion CT is highly accurate for the detection of ischemic brain lesions • Perfusion CT results in high radiation exposure, therefore low-dose protocols are required • Reduction of tube current down to 72 mAs produces sufficient perfusion maps.

  10. Deconvolution-Based CT and MR Brain Perfusion Measurement: Theoretical Model Revisited and Practical Implementation Details

    Science.gov (United States)

    Fieselmann, Andreas; Kowarschik, Markus; Ganguly, Arundhuti; Hornegger, Joachim; Fahrig, Rebecca

    2011-01-01

    Deconvolution-based analysis of CT and MR brain perfusion data is widely used in clinical practice and it is still a topic of ongoing research activities. In this paper, we present a comprehensive derivation and explanation of the underlying physiological model for intravascular tracer systems. We also discuss practical details that are needed to properly implement algorithms for perfusion analysis. Our description of the practical computer implementation is focused on the most frequently employed algebraic deconvolution methods based on the singular value decomposition. In particular, we further discuss the need for regularization in order to obtain physiologically reasonable results. We include an overview of relevant preprocessing steps and provide numerous references to the literature. We cover both CT and MR brain perfusion imaging in this paper because they share many common aspects. The combination of both the theoretical as well as the practical aspects of perfusion analysis explicitly emphasizes the simplifications to the underlying physiological model that are necessary in order to apply it to measured data acquired with current CT and MR scanners. PMID:21904538

  11. Quantitative study on lung volume and lung perfusion using SPECT and CT in thoracal tumors

    International Nuclear Information System (INIS)

    Beyer-Enke, S.A.; Goerich, J.; Strauss, L.G.

    1988-01-01

    22 patients with space occupying lesions in the thoracal region were investigated by computer tomography and by perfusion scintigraphy using SPECT. In order to evaluate the CT images quantitatively, the lung volume was determined using approximation method and compared with the perfusion in the SPECT study. For this, anatomically equivalent transaxial SPECT slices had been coordinated to the CT slices. Between the determined lung volumes and the activity in the ocrresponding layers, a statistically significant correlation was found. It could be shown that the stronger perfusion, frequently observed at the right side of the healthy lung, may be explained by an higher volume of the right pulmonary lobe. Whereas in benign displacing processes the relation activity to volume was similar to the one of the healthy lung, a strongly reduced perfusion together with inconspicuous lung volumes became apparent with malignant tumors. In addition to the great morphological evidence of CT and SPECT studies, additional informations regarding the dignity of displacing processes may be derived from the quantitative evaluation of both methods. (orig.) [de

  12. Deconvolution-Based CT and MR Brain Perfusion Measurement: Theoretical Model Revisited and Practical Implementation Details.

    Science.gov (United States)

    Fieselmann, Andreas; Kowarschik, Markus; Ganguly, Arundhuti; Hornegger, Joachim; Fahrig, Rebecca

    2011-01-01

    Deconvolution-based analysis of CT and MR brain perfusion data is widely used in clinical practice and it is still a topic of ongoing research activities. In this paper, we present a comprehensive derivation and explanation of the underlying physiological model for intravascular tracer systems. We also discuss practical details that are needed to properly implement algorithms for perfusion analysis. Our description of the practical computer implementation is focused on the most frequently employed algebraic deconvolution methods based on the singular value decomposition. In particular, we further discuss the need for regularization in order to obtain physiologically reasonable results. We include an overview of relevant preprocessing steps and provide numerous references to the literature. We cover both CT and MR brain perfusion imaging in this paper because they share many common aspects. The combination of both the theoretical as well as the practical aspects of perfusion analysis explicitly emphasizes the simplifications to the underlying physiological model that are necessary in order to apply it to measured data acquired with current CT and MR scanners.

  13. The value of whole-brain CT perfusion imaging and CT angiography using a 320-slice CT scanner in the diagnosis of MCI and AD patients

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Bo; Gu, Guo-jun; Jiang, Hong; Guo, Yi [Medical School of Tongji University, Department of Medical Imaging, Tongji Hospital, Shanghai (China); Shen, Xing [Traditional Chinese Hospital, Department of Radiology, Kun Shan, Jiangsu Province (China); Li, Bo; Zhang, Wei [Medical School of Jiaotong University, Department of Medical Imaging, Renji Hospital, Shanghai (China)

    2017-11-15

    To validate the value of whole-brain computed tomography perfusion (CTP) and CT angiography (CTA) in the diagnosis of mild cognitive impairment (MCI) and Alzheimer's disease (AD). Whole-brain CTP and four-dimensional CT angiography (4D-CTA) images were acquired in 30 MCI, 35 mild AD patients, 35 moderate AD patients, 30 severe AD patients and 50 normal controls (NC). Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and correlation between CTP and 4D-CTA were analysed. Elevated CBF in the left frontal and temporal cortex was found in MCI compared with the NC group. However, TTP was increased in the left hippocampus in mild AD patients compared with NC. In moderate and severe AD patients, hypoperfusion was found in multiple brain areas compared with NC. Finally, we found that the extent of arterial stenosis was negatively correlated with CBF in partial cerebral cortex and hippocampus, and positively correlated with TTP in these areas of AD and MCI patients. Our findings suggest that whole-brain CTP and 4D-CTA could serve as a diagnostic modality in distinguishing MCI and AD, and predicting conversion from MCI based on TTP of left hippocampus. (orig.)

  14. Quantitative CT myocardial perfusion : Development of a new imaging biomarker

    NARCIS (Netherlands)

    Pelgrim, Gert

    2017-01-01

    Recente ontwikkelingen in CT technieken hebben er voor gezorgd dat de evaluatie van ziekte in de kransslagaderen (coronaire hartziekte) is verschoven van het visueel opsporen van gebieden met verminderde doorbloeding, naar het kwantitatief beoordelen van de doorbloeding van het hart (perfusie). In

  15. Neuroradiological findings in primary progressive aphasia: CT, MRI and cerebral perfusion SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Sinnatamby, R. [Dept. of Radiology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Antoun, N.A. [Dept. of Radiology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Freer, C.E.L. [Dept. of Radiology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Miles, K.A. [Dept. of Nuclear Medicine, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Hodges, J.R. [Dept. of Neurology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom)

    1996-04-01

    Primary progressive aphasia (PPA) is defined as progressive decline in language for 2 or more years with preservation of activities of daily living and general cognitive functions. Whereas the clinical features of this syndrome have been well documented, the neuroradiological findings have not been studied systematically. We studied 13 patients with PPA retrospectively: 10 underwent CT, 12 MRI and 12 cerebral perfusion studies using {sup 99m}Tc-HMPAO SPECT. CT and MR images were scored for focal atrophy by two independent assessors. Initial qualitative assessment of SPECT images was confirmed by quantitative analysis. CY was normal in 5 patients. Focal atrophy, affecting predominantly the left temporal lobe, was seen in 4 of 10 patients on CT, and 10 of 12 on MRI. Atrophy was localised primarily to the superior and middle temporal gyri on MRI. All 12 patients who underwent SPECT had unilateral temporal lobe perfusion defects, in 2 patients of whom MRI was normal. CT is relatively insensitive to focal abnormalities in PPA; MRI and SPECT are the imaging modalities of choice. MRI allows accurate, specific localisation of atrophy with the temporal neocortex. SPECT may reveal a functional decrease in cerebral perfusion prior to establishment of structural change. (orig.)

  16. Neuroradiological findings in primary progressive aphasia: CT, MRI and cerebral perfusion SPECT

    International Nuclear Information System (INIS)

    Sinnatamby, R.; Antoun, N.A.; Freer, C.E.L.; Miles, K.A.; Hodges, J.R.

    1996-01-01

    Primary progressive aphasia (PPA) is defined as progressive decline in language for 2 or more years with preservation of activities of daily living and general cognitive functions. Whereas the clinical features of this syndrome have been well documented, the neuroradiological findings have not been studied systematically. We studied 13 patients with PPA retrospectively: 10 underwent CT, 12 MRI and 12 cerebral perfusion studies using 99m Tc-HMPAO SPECT. CT and MR images were scored for focal atrophy by two independent assessors. Initial qualitative assessment of SPECT images was confirmed by quantitative analysis. CY was normal in 5 patients. Focal atrophy, affecting predominantly the left temporal lobe, was seen in 4 of 10 patients on CT, and 10 of 12 on MRI. Atrophy was localised primarily to the superior and middle temporal gyri on MRI. All 12 patients who underwent SPECT had unilateral temporal lobe perfusion defects, in 2 patients of whom MRI was normal. CT is relatively insensitive to focal abnormalities in PPA; MRI and SPECT are the imaging modalities of choice. MRI allows accurate, specific localisation of atrophy with the temporal neocortex. SPECT may reveal a functional decrease in cerebral perfusion prior to establishment of structural change. (orig.)

  17. Dynamic CT myocardial perfusion imaging: detection of ischemia in a porcine model with FFR verification

    Science.gov (United States)

    Fahmi, Rachid; Eck, Brendan L.; Vembar, Mani; Bezerra, Hiram G.; Wilson, David L.

    2014-03-01

    Dynamic cardiac CT perfusion (CTP) is a high resolution, non-invasive technique for assessing myocardial blood ow (MBF), which in concert with coronary CT angiography enable CT to provide a unique, comprehensive, fast analysis of both coronary anatomy and functional ow. We assessed perfusion in a porcine model with and without coronary occlusion. To induce occlusion, each animal underwent left anterior descending (LAD) stent implantation and angioplasty balloon insertion. Normal ow condition was obtained with balloon completely de ated. Partial occlusion was induced by balloon in ation against the stent with FFR used to assess the extent of occlusion. Prospective ECG-triggered partial scan images were acquired at end systole (45% R-R) using a multi-detector CT (MDCT) scanner. Images were reconstructed using FBP and a hybrid iterative reconstruction (iDose4, Philips Healthcare). Processing included: beam hardening (BH) correction, registration of image volumes using 3D cubic B-spline normalized mutual-information, and spatio-temporal bilateral ltering to reduce partial scan artifacts and noise variation. Absolute blood ow was calculated with a deconvolutionbased approach using singular value decomposition (SVD). Arterial input function was estimated from the left ventricle (LV) cavity. Regions of interest (ROIs) were identi ed in healthy and ischemic myocardium and compared in normal and occluded conditions. Under-perfusion was detected in the correct LAD territory and ow reduction agreed well with FFR measurements. Flow was reduced, on average, in LAD territories by 54%.

  18. Efficacy of dynamic CT perfusion imaging in conjunction with three dimensional CT angiography for the evaluation of acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Nakaguchi, Hiroshi; Teraoka, Akira; Adachi, Shinobu; Yanagibashi, Kazutaka [Teraoka Memorial Hospital, Shinichi, Hiroshima (Japan)

    2003-01-01

    Through the use of a high-speed spiral CT scanner (GEMedical HiSpeedZX/i), CT/P/A technique, where conventional CT, CT perfusion imaging (CTP) and CT angiography (CTA) are consecutively performed, can now be performed with an imaging time of 90 seconds and a total contrast medium volume of 100 ml. A prospective clinical study was performed to ascertain the effectiveness of CT/P/A in diagnosing acute ischemic strokes. Twenty-nine consecutive patients of Teraoka Memorial Hospital suspected of suffering from the occlusion or constriction of cerebral arteries and who underwent CT/P/A within 3 hours from the onset served as subjects. The sensitivity, specificity, or Odds ratio of CTP and CTA in detecting lesions that caused cerebral infarction was calculated. CTP detected a hypoperfusion area with a sensitivity, specificity, and Odds ratio of 80%, 64%, and 7.2. The sensitivity in lobar infarcts, white matter infarcts, basal ganglia infarcts, and brainstem infarcts was 100%, 100%, 100%, 0% (p=0.0022). The sensitivity and Odds ratio of CT/P/A in cerebral infarcts differed according to the diameter of the infarcts. That with infarcts of 10 mm or more was 91%, 20. That with infarcts smaller than 10 mm was 50%, 2. CTA detected arterial lesions that caused cerebral ischemic attack with a sensitivity of 94% and specificity of 90%. The examination time for CT/P/A was 18 minutes, total radiation time being 90 seconds. Although CT/P/A was ineffective for the diagnosis of brainstem infarcts and lesions smaller than 10 mm, CT/P/A was useful in detecting moderate-sized hypoperfusion areas and arterial lesions three-dimensionally before an infarct is completed. (author)

  19. Performance of CT ASPECTS and Collateral Score in Risk Stratification: Can Target Perfusion Profiles Be Predicted without Perfusion Imaging?

    Science.gov (United States)

    Dehkharghani, S; Bammer, R; Straka, M; Bowen, M; Allen, J W; Rangaraju, S; Kang, J; Gleason, T; Brasher, C; Nahab, F

    2016-08-01

    Endovascular trials suggest that revascularization benefits a subset of acute ischemic stroke patients with large-artery occlusion and small-core infarct volumes. The objective of our study was to identify thresholds of noncontrast CT-ASPECTS and collateral scores on CT angiography that best predict ischemic core volume thresholds quantified by CT perfusion among patients with acute ischemic stroke. Fifty-four patients with acute ischemic stroke (collateral score of 3 had 100% specificity for identifying patients with a CBF core volume of ≤50 mL. NCCT-ASPECTS of ≤6 had 100% specificity for identifying patients with a CBF core volume of >50 mL. In our cohort, 44 (81%) patients had an NCCT-ASPECTS of ≥9, a CTA collateral score of 3, or an NCCT-ASPECTS of ≤6. Using an NCCT-ASPECTS of ≥9 or a CTA collateral score of 3 best predicts CBF core volume infarct of ≤50 mL, while an NCCT-ASPECTS of ≤6 best predicts a CBF core volume infarct of >50 mL. Together these thresholds suggest that a specific population of patients with acute ischemic stroke not meeting such profiles may benefit most from CTP imaging to determine candidacy for revascularization. © 2016 by American Journal of Neuroradiology.

  20. Quantitative Myocardial Perfusion with Dynamic Contrast-Enhanced Imaging in MRI and CT : Theoretical Models and Current Implementation

    NARCIS (Netherlands)

    Pelgrim, G J; Handayani, A; Dijkstra, H; Prakken, N H J; Slart, R H J A; Oudkerk, M; Van Ooijen, P M A; Vliegenthart, R; Sijens, P E

    2016-01-01

    Technological advances in magnetic resonance imaging (MRI) and computed tomography (CT), including higher spatial and temporal resolution, have made the prospect of performing absolute myocardial perfusion quantification possible, previously only achievable with positron emission tomography (PET).

  1. [CT perfusion imaging evaluation on hemodynamic changes of acute spontaneous intracerebral hemorrhage surrounding tissues].

    Science.gov (United States)

    Kuang, Yi; Chen, Weijian; Zheng, Kuikui; Fu, Jun; Hu, Zilong; Yang, Yunjun; Dai, Yichuan

    2015-11-17

    To discuss the hemodynamic changes in patients with acute supratentorial spontaneous intracerebral hemorrhage (within 72 hours) by using 320-slice of low-dose volume CT perfusion imaging. Twenty-six patients of The First Affiliated Hospital of Wenzhou Medical University during December 2012 to December 2013 with acute supratentorial SICH diagnosed by plain CT scanning and clinic were enrolled. With hematoma maximum level for reference, the hematoma volume, edema area and perfusion defect area were measured, and the perfusion parameters values of the marginal area and outer area of the intracerebral hematoma and contralateral mirror area were measured, including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and time-to-peak (TTP), and rCBF, rCBV, rMTT and rTTP were calculated by ipsilateral/contralateral value. The CBF, CBV of the marginal area were lower than the contralateral mirror area (tCBF=-8.125, tCBV=-8.671, PCBF, CBVperfusion defect area showed a positive linear relation with the volume of acute hematoma (r=0.440, Pperfusion defect area (r=0.400, r=0.81, PCT perfusion imaging can perfectly reflect the hemodynamic changes in brain tissuse after acute supratentorial SICH. Hypoperfusion was appeared in perihematomal area of acute supratentorial SICH. The perihematomal brain tissue may exists ischemic injury associated with the size of hematoma.The hematoma place holder effect, ischemic injury are the important cause of acute brain edema formation.

  2. CT study in Alzheimer's disease

    International Nuclear Information System (INIS)

    Arai, Heii; Kobayashi, Kazunari; Ikeda, Kenji; Nagao, Yoshiko; Ogihara, Ryuji; Kosaka, Kenji

    1983-01-01

    Cerebral atrophy on CT was studied in 18 patients with clinically diagnosed Alzheimer's disease and in 14 healthy age-matched subjects as the control. The patients with Alzheimer's disease were divided into three groups of Stages I, Ii and III, according to their clinical symptoms. The study of the measurement method disclosed that the computerized measurement involving calculation of the number of pixels contained within the range of the designated CT numbers is liable to produce errors for the determination of the subarachnoid spaces and the ventricles with calcified colloid plexus. Therefor, for the present study was the method adopted, in which the subarachnoid spaces and the ventricles are measured based on the number of pixels contained in the region of interest by tracing them on the display monitor. Then, both Subarachnoid Space Volume Index (SVI) and Ventricle Volume Index (VVI) were calculated as the indices for cortical atrophy and ventricular dilatation in a slice through the level of the foramen interventriculare Monroi and other three successive ones through upper regions. Cerebral atrophy observed on CT in Alzheimer patients is attributable to Alzheimer's disease processes, rather than to physiological aging of the brain. The degree of the atrophy increases in proportion to the clinical stage, and cortical atrophy is apparent even at Stage I, whereas ventricular dilatation becomes pronounced at later stage. CT is one of effective clinical tests for the diagnosis of Alzheimer's disease. (J.P.N.)

  3. CT perfusion-guided patient selection for endovascular recanalization in acute ischemic stroke: a multicenter study.

    Science.gov (United States)

    Turk, Aquilla S; Magarick, Jordan Asher; Frei, Don; Fargen, Kyle Michael; Chaudry, Imran; Holmstedt, Christine A; Nicholas, Joyce; Mocco, J; Turner, Raymond D; Huddle, Daniel; Loy, David; Bellon, Richard; Dooley, Gwendolyn; Adams, Robert; Whaley, Michelle; Fanale, Chris; Jauch, Edward

    2013-11-01

    The treatment of acute ischemic stroke is traditionally centered on time criteria, although recent evidence suggests that physiologic neuroimaging may be useful. In a multicenter study we evaluated the use of CT perfusion, regardless of time from symptom onset, in patients selected for intra-arterial treatment of ischemic stroke. Three medical centers retrospectively assessed stroke patients with a National Institute of Health Stroke Scale of ≥ 8, regardless of time from symptom onset. CT perfusion maps were qualitatively assessed. Patients with defined salvageable penumbra underwent intra-arterial revascularization of their occlusion. Functional outcome using the modified Rankin Score (mRS) was recorded. Two hundred and forty-seven patients were selected to undergo intra-arterial treatment based on CT perfusion imaging. The median time from symptom onset to procedure was 6 h. Patients were divided into two groups for analysis: ≤ 8 h and >8 h from symptom onset to endovascular procedure. We found no difference in functional outcome between the two groups (42.8% and 41.9% achieved 90-day mRS ≤ 2, respectively (p=1.0), and 54.9% vs 55.4% (p=1.0) achieved 90-day mRS ≤ 3, respectively). Overall, 48 patients (19.4%) had hemorrhages, of which 20 (8.0%) were symptomatic, with no difference between the groups (p=1.0). In a multicenter study, we demonstrated similar rates of good functional outcome and intracranial hemorrhage in patients with ischemic stroke when endovascular treatment was performed based on CT perfusion selection rather than time-guided selection. Our findings suggest that physiologic imaging-guided patient selection rather than time for endovascular reperfusion in ischemic stroke may be effective and safe.

  4. Dependence of quantitative accuracy of CT perfusion imaging on system parameters

    Science.gov (United States)

    Li, Ke; Chen, Guang-Hong

    2017-03-01

    Deconvolution is a popular method to calculate parametric perfusion parameters from four dimensional CT perfusion (CTP) source images. During the deconvolution process, the four dimensional space is squeezed into three-dimensional space by removing the temporal dimension, and a prior knowledge is often used to suppress noise associated with the process. These additional complexities confound the understanding about deconvolution-based CTP imaging system and how its quantitative accuracy depends on parameters and sub-operations involved in the image formation process. Meanwhile, there has been a strong clinical need in answering this question, as physicians often rely heavily on the quantitative values of perfusion parameters to make diagnostic decisions, particularly during an emergent clinical situation (e.g. diagnosis of acute ischemic stroke). The purpose of this work was to develop a theoretical framework that quantitatively relates the quantification accuracy of parametric perfusion parameters with CTP acquisition and post-processing parameters. This goal was achieved with the help of a cascaded systems analysis for deconvolution-based CTP imaging systems. Based on the cascaded systems analysis, the quantitative relationship between regularization strength, source image noise, arterial input function, and the quantification accuracy of perfusion parameters was established. The theory could potentially be used to guide developments of CTP imaging technology for better quantification accuracy and lower radiation dose.

  5. [Intratympanic corticosteroid perfusion in the therapy of Meniere's disease].

    Science.gov (United States)

    Sanković-Babić, Snezana; Kosanović, Rade; Ivanković, Zoran; Babac, Snezana; Tatović, Milica

    2014-01-01

    Over the last two decades the intratympanic perfusion of corticosteroids has been used as a minimally invasive surgical therapy of Meniere's disease. According to experimental studies the antiinflammatory, immunoprotective, antioxidant and neuroprotective role of the locally perfused corticosteroids was noticed in the inner ear structures. The recovery of action potentials in the cells of the Corti organ was confirmed as well as a decreased expression of aquaporine-1, a glycoprotein responsible for labyrinth hydrops and N and K ions derangement. The study showed results of intratympanic perfusion therapy with dexamethasone in patients with retractable Meniere's disease who are resistant to conservative treatment. Single doses of 4 mg/ml dexamethasone were given intratympanically in 19 patients with retractable Meniere's disease. Six single successive doses of dexamethasone were administered in the posteroinferior quadrant of the tympanic membrane. Follow-up of the patients was conducted by using a clinical questionnaire a month after completed perfusion series as well as on every third month up to one year. One month after completed first course of perfusions, in 78% of patients, vertigo problems completely ceased or were markedly reduced. The recovery of hearing function was recorded in 68% and marked tinnitus reduction in 84% of patients. After a year of follow-up, in 63% of patients the reduction of vertigo persisted, while hearing function was satisfactory in 52%. Tinitus reduction was present in 73% of patients. Intratympanic perfusion of dexamethasone in patients with Meniere's disease is a minimally invasive therapeutic method that contributes to the reduction of the intensity of vertigo recurrent attacks, decrease of the intensity of tinnitus and improvement of the average hearing threshold. Patients with chronic diseases and Meniere's disease who are contraindicted for systemic administration of cortocosteroids (hypertension, diabetes, glaucoma, peptic

  6. CT scan of Parkinson's disease

    International Nuclear Information System (INIS)

    Konishi, Tetsuro; Noguchi, Sadako; Nishitani, Hiroshi; Kitano, Haruo; Ikegami, Yoshinori.

    1981-01-01

    In forty-eight patients with Parkinson's disease, we examined the ventricular size and the degree of cortical atrophy which were measured by the photos of CT scan and compared them with their clinical symptoms and side effects of anti-parkinsonian drugs. The ventricular size was expressed as the ventricular ratio which is the percentage of superimposed lateral ventricular area to the white and gray matter area at the slice number 2B of CT scan photos. The degree of the cortical atrophy was expressed as the sulcal numbers which were clearly visualized at the slice number 3B or 4A of CT scan photos. We used the CT scan photos of age-matched other patients which did not show definit central nervous system abnormalities. Our findings were as follows: (1) The ventricular enlargement was observed in the parkinsonian patients who showed dementia and/or Yahr's classification grades IV or V. (2) There was no correlation between the duration of this disease and the L--dopa treatments with the ventricular size and sulcal numbers. (3) The side effects of drugs such as visual hallucination were tended to be observed in the patients who showed the ventricular enlargement. (4) There was no definite correlation between the degree of cortical atrophy with clinical symptoms and side effects of various drugs. These findings suggested that the ventricular enlargement in Parkinson's disease was an important sign of dementia and the tendency of appearance of side effects of various drugs. (author)

  7. Combined coronary angiography and myocardial perfusion by computed tomography in the identification of flow-limiting stenosis - The CORE320 study: An integrated analysis of CT coronary angiography and myocardial perfusion.

    Science.gov (United States)

    Magalhães, Tiago A; Kishi, Satoru; George, Richard T; Arbab-Zadeh, Armin; Vavere, Andrea L; Cox, Christopher; Matheson, Matthew B; Miller, Julie M; Brinker, Jeffrey; Di Carli, Marcelo; Rybicki, Frank J; Rochitte, Carlos E; Clouse, Melvin E; Lima, João A C

    2015-01-01

    The combination of coronary CT angiography (CTA) and myocardial CT perfusion (CTP) is gaining increasing acceptance, but a standardized approach to be implemented in the clinical setting is necessary. To investigate the accuracy of a combined coronary CTA and myocardial CTP comprehensive protocol compared to coronary CTA alone, using a combination of invasive coronary angiography and single photon emission CT as reference. Three hundred eighty-one patients included in the CORE320 trial were analyzed in this study. Flow-limiting stenosis was defined as the presence of ≥50% stenosis by invasive coronary angiography with a related perfusion defect by single photon emission CT. The combined CTA + CTP definition of disease was the presence of a ≥50% stenosis with a related perfusion defect. All data sets were analyzed by 2 experienced readers, aligning anatomic findings by CTA with perfusion defects by CTP. Mean patient age was 62 ± 6 years (66% male), 27% with prior history of myocardial infarction. In a per-patient analysis, sensitivity for CTA alone was 93%, specificity was 54%, positive predictive value was 55%, negative predictive value was 93%, and overall accuracy was 69%. After combining CTA and CTP, sensitivity was 78%, specificity was 73%, negative predictive value was 64%, positive predictive value was 0.85%, and overall accuracy was 75%. In a per-vessel analysis, overall accuracy of CTA alone was 73% compared to 79% for the combination of CTA and CTP (P perfusion defect. Copyright © 2015 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  8. An evaluation of the feasibility of assessment of volume perfusion for the whole lung by 128-slice spiral CT

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    Sun, Haitao [Imaging Center of Taian Central Hospital, Taian, Shandong (China); Gao, Fei; Li, Ning; Liu, Cheng [Shandong Univ., Shandong Medical Imaging Research Inst., CT Room, Shandong (China)], e-mail: liucheng491025@sina.com

    2013-10-15

    Background: Lung perfusion based on dynamic scanning cannot provide a quantitative assessment of the whole lung because of the limited coverage of the current computed tomography (CT) detector designs. Purpose: To evaluate the feasibility of dynamic volume perfusion CT (VPCT) of the whole lung using a 128-slice CT for the quantitative assessment and visualization of pulmonary perfusion. Material and Methods: Imaging was performed in a control group of 17 subjects who had no signs of disturbance of pulmonary function or diffuse lung disease, and 15 patients (five patients with acute pulmonary embolism and 10 with emphysema) who constituted the abnormal lung group. Dynamic VPCT was performed in all subjects, and pulmonary blood flow (PBF), pulmonary blood volume (PBV), and mean transit time (MTT) were calculated from dynamic contrast images with a coverage of 20.7 cm. Regional and volumetric PBF, PBV, and MTT were statistically evaluated and comparisons were made between the normal and abnormal lung groups. Results: Regional PBF (94.2{+-}36.5, 161.8 {+-}29.6, 185.7 {+-}38.1 and 125.5 {+-}46.1, 161.9 {+-}31.4, 169.3 {+-}51.7), PBV (6.7 {+-}2.8, 10.9 {+-}3.0, 12.9 {+-}4.5 and 9.9 {+-}4.6, 10.3 {+-}2.9, 11.9 {+-}4.5), and MTT (5.8 {+-}2.4, 4.5 {+-}1.3, 4.7 {+-}2.1 and 5.6 {+-}2.3, 4.3 {+-}1.5, 4.9 {+-}1.5) demonstrated significant differences in the gravitational and isogravitational directions in the normal lung group (P < 0.05). The PBF (154.2 {+-}30.6 vs. 94.9 {+-}15.9) and PBV (11.1 {+-}4.0 vs. 6.6 {+-}1.7) by dynamic VPCT showed significant differences between normal and abnormal lungs (P < 0.05), notwithstanding the four large lungs that had coverage > 20.7 cm. Conclusion: Dynamic VPCT of the whole lung is feasible for the quantitative assessment of pulmonary perfusion by 128-slice CT, and may in future permit the evaluation of both morphological and functional features of the whole lung in a single examination.

  9. Renal perfusion in chronic liver diseases: Evaluation by radiotechnetium renography

    International Nuclear Information System (INIS)

    Fanfani, G.; Fratello, A.; Mele, M.; Conte, E.; D'Addabbo, A.; Greco, L.

    1985-01-01

    Twenty-four patients with chronic liver diseases and seven normal controls were studied using renal and hepatic radiotechnetium angiography. The time-activity histograms generated were employed to calculate both the renal perfusion index (RPI) and the hepatic perfusion index (HPI). Renal perfusion proved to be reduced not only in cirrhotic patients but also in patients with aggressive chronic hepatitis, as well as in those with persistent chronic hepatitis. The HPI, which is to be considered as being strictly dependent on portal flow, only fell significantly in the group of cirrhotic patients. In all patient groups, the correlation coefficient between the HPI and RPI (mean of the two kidneys) was low (r=0.275) and not significant (P>0.05). After Warren's splenorenal derivation, renal perfusion did not improve but worsened, particularly in the left kidney where derivation anastomosis probably caused a venous overload. (orig.)

  10. Feasibility of perfusion CT technique integrated into conventional 18FDG/PET-CT studies in lung cancer patients: clinical staging and functional information in a single study.

    Science.gov (United States)

    Ippolito, Davide; Capraro, Cristina; Guerra, Luca; De Ponti, Elena; Messa, Cristina; Sironi, Sandro

    2013-01-01

    To assess the additional functional vascular information and the relationship between perfusion measurements and glucose metabolism (SUVmax) obtained by including a perfusion CT study in a whole-body contrast-enhanced PET/CT protocol in primary lung cancer lesions. Enrolled in this prospective study were 34 consecutive patients with a biopsy-proven diagnosis of lung cancer who were referred for contrast-enhanced PET/CT staging. This prospective study was approved by our institutional review board, and informed consent was obtained from all patients. Perfusion CT was performed with the following parameters: 80 kV, 200 mAs, 30 scans during intravenous injection of 50 ml contrast agent, flow rate 5 ml/s. Another bolus of contrast medium (3.5 ml/s, 80 ml, 60-s delay) was administered to ensure a full diagnostic contrast-enhanced CT scan for clinical staging. The perfusion CT data were used to calculate a range of tumour vascularity parameters (blood flow, blood volume and mean transit time), and tumour FDG uptake (SUVmax) was used as a metabolic indicator. Quantitative and functional parameters were compared and in relation to location, histology and tumour size. The nonparametric Kruskal-Wallis rank sum test was used for statistical analysis. A cut-off value of 3 cm was used according to the TNM classification to discriminate between T1 and T2 tumours (i.e. T1b vs. T2a). There were significant perfusion differences (lower blood volumes and higher mean transit time) between tumours with diameter >30 mm and tumours with diameter 30 mm in diameter. Perfusion CT combined with PET/CT is feasible technique that may provide additional functional information about vascularity and tumour aggressiveness as a result of lower perfusion and higher metabolism shown by larger lesions.

  11. Correlation between CT perfusion parameters and microvessel density and vascular endothelial growth factor in adrenal tumors.

    Directory of Open Access Journals (Sweden)

    Hai-yan Qin

    Full Text Available We evaluated the correlation between computed tomography (CT perfusion parameters and markers of angiogenesis in adrenal adenomas and non-adenomas to determine if perfusion CT can be used to distinguish between them. Thirty-four patients with pathologically-confirmed adrenal tumors (17 adenomas, 17 non-adenomas received CT perfusion imaging before surgery. CT perfusion parameters (blood flow [BF], blood volume [BV], mean transit time [MTT], and permeability surface area product [PS] were calculated. Tumor tissue sections were examined with immunohistochemical methods for vascular endothelial growth factor (VEGF expression and microvessel density (MVD. The mean age of the 34 patients was 43 years. The median BV was significantly higher in adenomas than in non-adenomas [12.3 ml/100 g, inter-quartile range (IQR: 10.4 to 16.5 ml/100 g vs. 8.8 ml/100 g, IQR: 3.3 to 9.4 ml/100 g, p=0.001]. Differences in BF, MTT, and PS parameter values between adenomas and non-adenomas were not significant (p>0.05. The mean MVD was significantly higher in adenomas compared to non-adenomas (98.5 ± 28.5 vs. 53.5 ± 27.0, p<0.0001. Adenomas also expressed significantly higher median VEGF than non-adenomas (65%, IQR: 50 to 79% vs. 45%, IQR: 35 to 67%, p=0.02. A moderately strong correlation between BF and VEGF (r=0.53, p=0.03 and between BV and MVD among adenomas (r=0.57, p=0.02 exist. Morphology, MVD, and VEGF expression in adenomas differ significantly from non-adenomas. Of the CT perfusion parameters examined, both BF and BV correlate with MVD, but only BF correlates with VEGF, and only in adenomas. The significant difference in BV suggests that BV may be used to differentiate adenomas from non-adenomas. However, the small difference in BV shows that it may only be possible to use BV to identify adenomas vs. non-adenomas at extreme BV values.

  12. Dynamic CT Perfusion Imaging for the Detection of Crossed Cerebellar Diaschisis in Acute Ischemic Stroke

    International Nuclear Information System (INIS)

    Jeon, Young Wook; Kim, Seo Hyun; Lee, Ji Young; Whang, Kum; Kim, Myung Soon; Kim, Young Ju; Lee, Myeong Sub; Brain Reserch Group

    2012-01-01

    Although the detection of crossed cerebellar diaschisis (CCD) by means of different imaging modalities is well described, little is known about its diagnosis by computed tomography perfusion (CTP) imaging. We investigated the detection rate of CCD by CTP imaging and the factors related to CCD on CTP images in patients with acute ischemic stroke. CT perfusion maps of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time-to-peak (TTP) obtained from 81 consecutive patients affected by an acute ischemic stroke were retrospectively reviewed. Whole-brain perfusion maps were obtained with a multichannel CT scanner using the toggling-table technique. The criteria for CCD was a unilateral supratentorial ischemic lesion and an accompanying decrease in perfusion of the contralateral cerebellar hemisphere on the basis of CTP maps by visual inspection without a set threshold. Maps were quantitatively analyzed in CCD positive cases. The criteria for CCD were fulfilled in 25 of the 81 cases (31%). Detection rates per CTP map were as follows: MTT (31%) > TTP (21%) > CBF (9%) > CBV (6%). Supratentorial ischemic volume, degree of perfusion reduction, and infratentorial asymmetry index correlated strongly (R, 0.555-0.870) and significantly (p < 0.05) with each other in CCD-positive cases. It is possible to detect CCD on all four of the CTP-based maps. Of these maps, MTT is most sensitive in detecting CCD. Our data indicate that CTP imaging is a valid tool for the diagnosis of CCD in patients affected by an acute hemispheric stroke.

  13. Dynamic CT Perfusion Imaging for the Detection of Crossed Cerebellar Diaschisis in Acute Ischemic Stroke

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Young Wook; Kim, Seo Hyun; Lee, Ji Young; Whang, Kum; Kim, Myung Soon; Kim, Young Ju; Lee, Myeong Sub; Brain Reserch Group [Wonju Christian Hospital, Yonsei University Wonju University College of Medicine, Wonju (Korea, Republic of)

    2012-01-15

    Although the detection of crossed cerebellar diaschisis (CCD) by means of different imaging modalities is well described, little is known about its diagnosis by computed tomography perfusion (CTP) imaging. We investigated the detection rate of CCD by CTP imaging and the factors related to CCD on CTP images in patients with acute ischemic stroke. CT perfusion maps of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time-to-peak (TTP) obtained from 81 consecutive patients affected by an acute ischemic stroke were retrospectively reviewed. Whole-brain perfusion maps were obtained with a multichannel CT scanner using the toggling-table technique. The criteria for CCD was a unilateral supratentorial ischemic lesion and an accompanying decrease in perfusion of the contralateral cerebellar hemisphere on the basis of CTP maps by visual inspection without a set threshold. Maps were quantitatively analyzed in CCD positive cases. The criteria for CCD were fulfilled in 25 of the 81 cases (31%). Detection rates per CTP map were as follows: MTT (31%) > TTP (21%) > CBF (9%) > CBV (6%). Supratentorial ischemic volume, degree of perfusion reduction, and infratentorial asymmetry index correlated strongly (R, 0.555-0.870) and significantly (p < 0.05) with each other in CCD-positive cases. It is possible to detect CCD on all four of the CTP-based maps. Of these maps, MTT is most sensitive in detecting CCD. Our data indicate that CTP imaging is a valid tool for the diagnosis of CCD in patients affected by an acute hemispheric stroke.

  14. Peritumoral brain edema in intracranial tumor evaluated by CT perfusion imaging

    International Nuclear Information System (INIS)

    Shi Yuxin; Xu Jianfeng

    2005-01-01

    Objective: To semi-quantitatively evaluate the cerebral perfusion in the peritumoral brain edema of cerebral tumors using CT perfusion imaging. Methods: Twenty-one patients with peritumoral brain edema (including pathologically confirmed meningiomas n=4, metastasis n=10, gliomas n=7) were examined by CT perfusion imaging. The regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), and mean transit time (MTT) were calculated for peritumoral brain edema and the contralateralwhite matter. The rCBF and rCBV were compared between peritumoral brain edema and the contralateral white matter. The mean ratios (edema/contralateral white matter) of rCBF and rCBV were compared among the three tumors. Results: The rCBF and rCBV of peritumoral brain edema were significantly lower than those of contralateral white matter in patients with meningiomas and metastasis (rCBF: t=2.92 and 3.82, P 0.05). The mean ratios (edema/contralateralwhite matter) of rCBF and rCBV were not significantly different between meningiomas and metastasis (t=0.23 and 0.73, P>0.05), but both of them were significantly lower than those of gliomas (t=3.05 and 3.37, P<0.01, 0.005). Conclusion: The rCBF and rCBV in peritumoral brain edema were significantly lower than those of contralateral white matter in patients with meningiomas and metastasis, while almost the same with or higher than those of contralateral white matter in patients with gliomas. CT perfusion can provide quantitative information of blood flow in peritumoral brain edema, and is useful in the diagnosis and follow-up of cerebral tumors. (authors)

  15. Quantitative myocardial perfusion imaging in a porcine ischemia model using a prototype spectral detector CT system

    Science.gov (United States)

    Fahmi, Rachid; Eck, Brendan L.; Levi, Jacob; Fares, Anas; Dhanantwari, Amar; Vembar, Mani; Bezerra, Hiram G.; Wilson, David L.

    2016-03-01

    We optimized and evaluated dynamic myocardial CT perfusion (CTP) imaging on a prototype spectral detector CT (SDCT) scanner. Simultaneous acquisition of energy sensitive projections on the SDCT system enabled projection-based material decomposition, which typically performs better than image-based decomposition required by some other system designs. In addition to virtual monoenergetic, or keV images, the SDCT provided conventional (kVp) images, allowing us to compare and contrast results. Physical phantom measurements demonstrated linearity of keV images, a requirement for quantitative perfusion. Comparisons of kVp to keV images demonstrated very significant reductions in tell-tale beam hardening (BH) artifacts in both phantom and pig images. In phantom images, consideration of iodine contrast to noise ratio and small residual BH artifacts suggested optimum processing at 70 keV. The processing pipeline for dynamic CTP measurements included 4D image registration, spatio-temporal noise filtering, and model-independent singular value decomposition deconvolution, automatically regularized using the L-curve criterion. In normal pig CTP, 70 keV perfusion estimates were homogeneous throughout the myocardium. At 120 kVp, flow was reduced by more than 20% on the BH-hypo-enhanced myocardium, a range that might falsely indicate actionable ischemia, considering the 0.8 threshold for actionable FFR. With partial occlusion of the left anterior descending (LAD) artery (FFR  perfusion defects at 70 keV were correctly identified in the LAD territory. At 120 kVp, BH affected the size and flow in the ischemic area; e.g. with FFR ≈ 0.65, the anterior-to-lateral flow ratio was 0.29  ±  0.01, over-estimating stenosis severity as compared to 0.42  ±  0.01 (p  CT.

  16. Diagnostic Accuracy of Simulated Low-Dose Perfusion CT to Detect Cerebral Perfusion Impairment after Aneurysmal Subarachnoid Hemorrhage: A Retrospective Analysis.

    Science.gov (United States)

    Afat, Saif; Brockmann, Carolin; Nikoubashman, Omid; Müller, Marguerite; Thierfelder, Kolja M; Brockmann, Marc A; Nikolaou, Konstantin; Wiesmann, Martin; Kim, Jong Hyo; Othman, Ahmed E

    2018-01-08

    Purpose To evaluate diagnostic accuracy of low-dose volume perfusion (VP) computed tomography (CT) compared with original VP CT regarding the detection of cerebral perfusion impairment after aneurysmal subarachnoid hemorrhage. Materials and Methods In this retrospective study, 85 patients (mean age, 59.6 years; 62 women) with aneurysmal subarachnoid hemorrhage and who were suspected of having cerebral vasospasm at unenhanced CT and VP CT (tube voltage, 80 kVp; tube current-time product, 180 mAs) were included, 37 of whom underwent digital subtraction angiography (DSA) within 6 hours. Low-dose VP CT data sets at tube current-time product of 72 mAs were retrospectively generated by validated realistic simulation. Perfusion maps were generated from both data sets and reviewed by two neuroradiologists for overall image quality, diagnostic confidence and presence and/or severity of perfusion impairment indicating vasospasm. An interventional neuroradiologist evaluated 16 vascular segments at DSA. Diagnostic accuracy of low-dose VP CT was calculated with original VP CT as reference standard. Agreement between findings of both data sets was assessed by using weighted Cohen κ and findings were correlated with DSA by using Spearman correlation. After quantitative volumetric analysis, lesion volumes were compared on both VP CT data sets. Results Low-dose VP CT yielded good ratings of image quality and diagnostic confidence and classified all patients correctly with high diagnostic accuracy (sensitivity, 99.0%; specificity, 99.5%) without significant differences regarding presence and/or severity of perfusion impairment between original and low-dose data sets (Z = -0.447; P = .655). Findings of both data sets correlated significantly with DSA (original, r = 0.671; low dose, r = 0.667). Lesion volume was comparable for both data sets (relative difference, 5.9% ± 5.1 [range, 0.2%-25.0%; median, 4.0%]) with strong correlation (r = 0.955). Conclusion The results suggest that

  17. Impairment of myocardial perfusion in children with sickle cell disease

    International Nuclear Information System (INIS)

    Maunoury, C.; Acar, P.; Montalembert, M. de

    2003-01-01

    While brain, bone and spleen strokes are well documented in children with sickle cell disease (SCD), impairment of myocardial perfusion is an unknown complication. Non invasive techniques such as exercise testing and echocardiography have a low sensitivity to detect myocardial ischemia in patients with SCD. We have prospectively assessed myocardial perfusion with Tl-201 SPECT in 23 patients with SCD (10 female, 13 male, mean age 12 ± 5 years). Myocardial SPECT was performed after stress and 3 hours later after reinjection on a single head gamma camera equipped with a LEAP collimator (64 x 64 matrix size format, 30 projections over 180 deg C, 30 seconds per step). Left ventricular ejection fraction (LVEF) was assessed by equilibrium radionuclide angiography at rest on the same day. Myocardial perfusion was impaired in 14/23 patients: 9 reversible defects and 5 fixed defects. The left ventricular cavity was dilated in 14/23 patients. The mean LVEF was 63 ± 9%. There was no relationship between myocardial perfusion and left ventricular dilation or function. The frequent impairment of myocardial perfusion in children with SCD could lead to suggest a treatment with hydroxyurea, an improvement of perfusion can be noted with hydroxyurea. (author)

  18. Multiparametric Monitoring of Early Response to Antiangiogenic Therapy: A Sequential Perfusion CT and PET/CT Study in a Rabbit VX2 Tumor Model

    Directory of Open Access Journals (Sweden)

    Jung Im Kim

    2014-01-01

    Full Text Available Objectives. To perform dual analysis of tumor perfusion and glucose metabolism using perfusion CT and FDG-PET/CT for the purpose of monitoring the early response to bevacizumab therapy in rabbit VX2 tumor models and to assess added value of FDG-PET to perfusion CT. Methods. Twenty-four VX2 carcinoma tumors implanted in bilateral back muscles of 12 rabbits were evaluated. Serial concurrent perfusion CT and FDG-PET/CT were performed before and 3, 7, and 14 days after bevacizumab therapy (treatment group or saline infusion (control group. Perfusion CT was analyzed to calculate blood flow (BF, blood volume (BV, and permeability surface area product (PS; FDG-PET was analyzed to calculate SUVmax, SUVmean, total lesion glycolysis (TLG, entropy, and homogeneity. The flow-metabolic ratio (FMR was also calculated and immunohistochemical analysis of microvessel density (MVD was performed. Results. On day 14, BF and BV in the treatment group were significantly lower than in the control group. There were no significant differences in all FDG-PET-derived parameters between both groups. In the treatment group, FMR prominently decreased after therapy and was positively correlated with MVD. Conclusions. In VX2 tumors, FMR could provide further insight into the early antiangiogenic effect reflecting a mismatch in intratumor blood flow and metabolism.

  19. Multiparametric monitoring of early response to antiangiogenic therapy: a sequential perfusion CT and PET/CT study in a rabbit VX2 tumor model.

    Science.gov (United States)

    Kim, Jung Im; Lee, Hyun-Ju; Kim, Young Jae; Kim, Kwang Gi; Lee, Kyung Won; Lee, Jae Ho; Lee, Hak Jong; Lee, Won Woo

    2014-01-01

    To perform dual analysis of tumor perfusion and glucose metabolism using perfusion CT and FDG-PET/CT for the purpose of monitoring the early response to bevacizumab therapy in rabbit VX2 tumor models and to assess added value of FDG-PET to perfusion CT. Twenty-four VX2 carcinoma tumors implanted in bilateral back muscles of 12 rabbits were evaluated. Serial concurrent perfusion CT and FDG-PET/CT were performed before and 3, 7, and 14 days after bevacizumab therapy (treatment group) or saline infusion (control group). Perfusion CT was analyzed to calculate blood flow (BF), blood volume (BV), and permeability surface area product (PS); FDG-PET was analyzed to calculate SUVmax, SUVmean, total lesion glycolysis (TLG), entropy, and homogeneity. The flow-metabolic ratio (FMR) was also calculated and immunohistochemical analysis of microvessel density (MVD) was performed. On day 14, BF and BV in the treatment group were significantly lower than in the control group. There were no significant differences in all FDG-PET-derived parameters between both groups. In the treatment group, FMR prominently decreased after therapy and was positively correlated with MVD. In VX2 tumors, FMR could provide further insight into the early antiangiogenic effect reflecting a mismatch in intratumor blood flow and metabolism.

  20. Measuring myocardial perfusion

    DEFF Research Database (Denmark)

    Qayyum, A A; Kastrup, J

    2015-01-01

    Recently, focus has changed from anatomical assessment of coronary arteries towards functional testing to evaluate the effect of stenosis on the myocardium before intervention. Besides positron-emission tomography (PET), cardiac MRI (CMR), and cardiac CT are able to measure myocardial perfusion......-known and is used in routine clinical practice. However, PET uses radioactive tracers and has a lower spatial resolution compared to CMR and CT. CMR and CT are emerging techniques in the field of myocardial perfusion imaging. CMR uses magnetic resonance to obtain images, whereas CT uses x-rays during first....... Myocardial perfusion abnormalities are the first sign of the ischaemic cascade in the development of coronary artery disease (CAD). PET is considered the non-invasive clinical reference standard for absolute quantification of myocardial perfusion. The diagnostic and prognostic value of PET is well...

  1. Assessing tumor treatment response and prognosis in non-small cell lung cancer with perfusion CT

    International Nuclear Information System (INIS)

    Wang Jianwei; Wu Ning; Song Ying

    2010-01-01

    Objective: To prospectively investigate whether any of the perfusion parameters would predict early tumor response to chemotherapy and/or radiotherapy and prognosis in non-small cell lung cancer (NSCLC). Methods: In a prospective series, Perfusion CT were performed in 152 patients suspected lung cancer with 16-slice or 8-slice multislice CT. Contrast medium (50 ml) was injected at a rate of 4 ml/s with a power injector. The scanning delay was 10 seconds and the scanning time was 50 seconds. Among 152 patients, 123 patients were proved lung cancer by pathology. With the perfusion 3.0 software, the parameters including blood flow (BF), blood volume (BV), mean transit time (MTT) and capillary permeability surface area product (PS) were calculated. The perfusion image quality was evaluated on a 4-1eveal scale. The treatment response after chemotherapy and (or) radiotherapy was assessed with Response Evaluation Criteria in Solid Tumors (RECIST), and then the relationship between perfusion parameters with early tumor response to chemotherapy and (or) radiotherapy was evaluated. Student t test and Kaplan-Meier estimates were used for data analysis. Results: In 84 patients (68.3%), the perfusion image quality was staged level 2 (moderate) and level 3 (good). Among them, 35 patients with NSCLC were assessed with RECIST after chemotherapy and (or) radiotherapy. In these 35 patients, The BF of responders and nonresponders was (81.0 ± 33.6)and (56.3 ± 23.1) ml · min -1 ·100 g -1 , respectively, which was significantly different(t=2.393, P=0.023). The median PFS of low-BF group (BF ≤ 80 ml · min -1 · 100 g -1 ) and high-BF group (BF>80 ml · min -1 · 100 g -1 ) was 11.8 and 8.0 months respectively (P>0.05), and the median PFS of low-BV group (BF ≤ 6 ml/100 g -1 ) and high-BV group (BF>6 ml/100 g -1 ) was 9.2 and 8.0 months respectively(P>0.05), both of them were not significantly different. Conclusion: NSCLC in high perfusion are relatively sensitive to chemotherapy

  2. Prediction of outcome in patients with suspected acute ischaemic stroke with CT perfusion and CT angiography: the Dutch acute stroke trial (DUST) study protocol.

    Science.gov (United States)

    van Seeters, Tom; Biessels, Geert Jan; van der Schaaf, Irene C; Dankbaar, Jan Willem; Horsch, Alexander D; Luitse, Merel J A; Niesten, Joris M; Mali, Willem P T M; Kappelle, L Jaap; van der Graaf, Yolanda; Velthuis, Birgitta K

    2014-02-25

    Prediction of clinical outcome in the acute stage of ischaemic stroke can be difficult when based on patient characteristics, clinical findings and on non-contrast CT. CT perfusion and CT angiography may provide additional prognostic information and guide treatment in the early stage. We present the study protocol of the Dutch acute Stroke Trial (DUST). The DUST aims to assess the prognostic value of CT perfusion and CT angiography in predicting stroke outcome, in addition to patient characteristics and non-contrast CT. For this purpose, individualised prediction models for clinical outcome after stroke based on the best predictors from patient characteristics and CT imaging will be developed and validated. The DUST is a prospective multi-centre cohort study in 1500 patients with suspected acute ischaemic stroke. All patients undergo non-contrast CT, CT perfusion and CT angiography within 9 hours after onset of the neurological deficits, and, if possible, follow-up imaging after 3 days. The primary outcome is a dichotomised score on the modified Rankin Scale, assessed at 90 days. A score of 0-2 represents good outcome, and a score of 3-6 represents poor outcome. Three logistic regression models will be developed, including patient characteristics and non-contrast CT (model A), with addition of CT angiography (model B), and CT perfusion parameters (model C). Model derivation will be performed in 60% of the study population, and model validation in the remaining 40% of the patients. Additional prognostic value of the models will be determined with the area under the curve (AUC) from the receiver operating characteristic (ROC) curve, calibration plots, assessment of goodness-of-fit, and likelihood ratio tests. This study will provide insight in the added prognostic value of CTP and CTA parameters in outcome prediction of acute stroke patients. The prediction models that will be developed in this study may help guide future treatment decisions in the acute stage of

  3. 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.

  4. Wavelet-based calculation of cerebral angiographic data from time-resolved CT perfusion acquisitions.

    Science.gov (United States)

    Havla, Lukas; Thierfelder, Kolja M; Beyer, Sebastian E; Sommer, Wieland H; Dietrich, Olaf

    2015-08-01

    To evaluate a new approach for reconstructing angiographic images by application of wavelet transforms on CT perfusion data. Fifteen consecutive patients with suspected stroke were examined with a multi-detector CT acquiring 32 dynamic phases (∆t = 1.5s) of 99 slices (total slab thickness 99mm) at 80kV/200mAs. Thirty-five mL of iomeprol-350 was injected (flow rate = 4.5mL/s). Angiographic datasets were calculated after initial rigid-body motion correction using (a) temporally filtered maximum intensity projections (tMIP) and (b) the wavelet transform (Paul wavelet, order 1) of each voxel time course. The maximum of the wavelet-power-spectrum was defined as the angiographic signal intensity. The contrast-to-noise ratio (CNR) of 18 different vessel segments was quantified and two blinded readers rated the images qualitatively using 5pt Likert scales. The CNR for the wavelet angiography (501.8 ± 433.0) was significantly higher than for the tMIP approach (55.7 ± 29.7, Wilcoxon test p wavelet angiography with median scores of 4/4 (reader 1/reader 2) than the tMIP (scores of 3/3). The proposed calculation approach for angiography data using temporal wavelet transforms of intracranial CT perfusion datasets provides higher vascular contrast and intrinsic removal of non-enhancing structures such as bone. • Angiographic images calculated with the proposed wavelet-based approach show significantly improved contrast-to-noise ratio. • CT perfusion-based wavelet angiography is an alternative method for vessel visualization. • Provides intrinsic removal of non-enhancing structures such as bone.

  5. Correlation between the Quantifiable Parameters of Whole Solitary Pulmonary Nodules Perfusion Imaging Derived with Dynamic CT and Nodules Size

    Directory of Open Access Journals (Sweden)

    Shiyuan LIU

    2009-05-01

    Full Text Available Background and objective The solitary pulmonary nodules (SPNs is one of the most common findings on chest radiographs. The blood flow patterns of the biggest single SPNs level has been studied. This assessment may be only a limited sample of the entire region of interest (ROI and is unrepresentative of the SPNs as a volume. Ideally, SPNs volume perfusion should be measured. The aim of this study is to evaluate the correlation between the quantifiableparameters of SPNs volume perfusion imaging derived with 16-slice spiral CT and 64-slice spiral CT and nodules size. Methods Sixty-five patients with SPNs (diameter≤3 cm; 42 malignant; 12 active inflammatory; 11 benign underwent multi-location dynamic contrast material-enhanced serial CT scanning mode with stable table were performed; The mean values of valid sections were calculated, as the quantifiable parameters of volume SPNs perfusion imaging derived with16-slice spiral CT and 64-slice spiral CT. The correlation between the quantifiable parameters of SPNs volume perfusion imaging derived with 16-slice spiral CT and 64-slice spiral CT and nodules size were assessed by means of linear regression analysis. Results No significant correlations were found between the nodules size and each of the peak height (PHSPN (32.15 Hu±14.55 Hu,ratio of peak height of the SPN to that of the aorta (SPN-to-A ratio(13.20±6.18%, perfusion(PSPN (29.79±19.12 mLmin-1100 g-1 and mean transit time (12.95±6.53 s (r =0.081, P =0.419; r =0.089, P =0.487; r =0.167, P =0.077; r =0.023, P =0.880. Conclusion No significant correlations were found between the quantifiable parameters of SPNs volume perfusion imaging derived with 16-slice spiral CT and 64-slice spiral CT and nodules size.

  6. Investigation of the potential causes of partial scan artifacts in dynamic CT myocardial perfusion imaging

    Science.gov (United States)

    Tao, Yinghua; Speidel, Michael; Szczykutowicz, Timothy; Chen, Guang-Hong

    2014-03-01

    In recent years, there have been several findings regarding CT number variations (partial scan artifact or PSA) across time in dynamic myocardial perfusion studies with short scan gated reconstruction. These variations are correlated with the view angle range corresponding to the short scan acquisition for a given cardiac phase, which can vary from one cardiac cycle to another due to the asynchrony between heart rate and gantry rotation speed. In this study, we investigate several potential causes of PSA, including noise, beam hardening and scatter, using numerical simulations. In addition, we investigate partial scan artifact in a single source 64-slice diagnostic CT scanner in vivo data sets, and report its effect on perfusion analysis. Results indicated that among all three factors investigated, scatter can cause obvious partial scan artifact in dynamic myocardial perfusion imaging. Further, scatter is a low frequency phenomenon and is not heavily dependent on the changing contrasts, as both the frequency method and the virtual scan method are effective in reducing partial scan artifact. However, PSA does not necessarily lead to different blood volume maps compared to the full scan, because these maps are usually generated with a curve fitting procedure.

  7. CT perfusion mapping of hemodynamic disturbances associated to acute spontaneous intracerebral hemorrhage

    International Nuclear Information System (INIS)

    Fainardi, Enrico; Borrelli, Massimo; Saletti, Andrea; Ceruti, Stefano; Tamarozzi, Riccardo; Schivalocchi, Roberta; Cavallo, Michele; Azzini, Cristiano; Chieregato, Arturo

    2008-01-01

    We sought to quantify perfusion changes associated to acute spontaneous intracerebral hemorrhage (SICH) by means of computed tomography perfusion (CTP) imaging. We studied 89 patients with supratentorial SICH at admission CT by using CTP scanning obtained within 24 h after symptom onset. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV) and mean transit time (rMTT) levels were measured in four different regions of interest manually outlined on CT scan: (1) hemorrhagic core; (2) perihematomal low-density area; (3) 1 cm rim of normal-appearing brain tissue surrounding the perilesional area; and (4) a mirrored area, including the clot and the perihematomal region, located in the non-lesioned contralateral hemisphere. rCBF, rCBV, and rMTT mean levels showed a centrifugal distribution with a gradual increase from the core to the periphery (p 20 ml) hematomas (p<0.01 and p <0.02, respectively). Multi-parametric CTP mapping of acute SICH indicates that perfusion values show a progressive improvement from the core to the periphery. In the first 24 h, perihemorrhagic region was hypoperfused with CTP values which were not suggestive of ischemic penumbra destined to survive but more likely indicative of edema formation. These findings also argue for a potential influence of early amounts of bleeding on perihematomal hemodynamic abnormalities. (orig.)

  8. Image registration and analysis for quantitative myocardial perfusion: application to dynamic circular cardiac CT

    Science.gov (United States)

    Isola, A. A.; Schmitt, H.; van Stevendaal, U.; Begemann, P. G.; Coulon, P.; Boussel, L.; Grass, M.

    2011-09-01

    Large area detector computed tomography systems with fast rotating gantries enable volumetric dynamic cardiac perfusion studies. Prospectively, ECG-triggered acquisitions limit the data acquisition to a predefined cardiac phase and thereby reduce x-ray dose and limit motion artefacts. Even in the case of highly accurate prospective triggering and stable heart rate, spatial misalignment of the cardiac volumes acquired and reconstructed per cardiac cycle may occur due to small motion pattern variations from cycle to cycle. These misalignments reduce the accuracy of the quantitative analysis of myocardial perfusion parameters on a per voxel basis. An image-based solution to this problem is elastic 3D image registration of dynamic volume sequences with variable contrast, as it is introduced in this contribution. After circular cone-beam CT reconstruction of cardiac volumes covering large areas of the myocardial tissue, the complete series is aligned with respect to a chosen reference volume. The results of the registration process and the perfusion analysis with and without registration are evaluated quantitatively in this paper. The spatial alignment leads to improved quantification of myocardial perfusion for three different pig data sets.

  9. Radiation dose from volumetric helical perfusion CT of the thorax, abdomen or pelvis

    International Nuclear Information System (INIS)

    Goh, Vicky; Dattani, Minaxi; Tam, Emily; Patel, Shilpan; Juttla, Jaspal; Simcock, Ian; Stirling, James; Farwell, Joseph; Shekhdar, Jane; Aird, Edwin; Mandeville, Henry; Hoskin, P.

    2011-01-01

    To evaluate the radiation doses delivered during volumetric helical perfusion CT of the thorax, abdomen or pelvis. The dose-length product (DLP) and CT dose index (CTDIvol) were recorded and effective dose (E) determined for patients undergoing CT (4D adaptive spiral) for tumour evaluation. Image noise and contrast to noise (CNR) at peak enhancement were also assessed for quality. Forty two consecutive examinations were included: thorax (16), abdomen (10), pelvis (16). Z-axis coverage ranged from 11.4 to 15.7 cm. Mean DLP was 1288.8 mGy.cm (range: 648 to 2456 mGy.cm). Mean CTDIvol was 96.2 mGy (range: 32.3 to 169.4 mGy). Mean effective dose was 19.6 mSv (range: 12.3 mSv to 36.7 mSv). In comparison mean DLP and effective dose was 885.2 mGy.cm (range: 504 to 1633 mGy.cm) and 13.3 mSV (range: 7.8 to 24.5 mSv) respectively for the standard staging CT thorax, abdomen and pelvis. Mean tumour CNR at peak enhancement was 1.87. The radiation dose imposed by perfusion CT was on average 1.5 times that of a CT thorax, abdomen and pelvis. The dose is not insubstantial, and must be balanced by the potential clinical utility of additional physiologic data. Further efforts towards dose reduction should be encouraged. (orig.)

  10. Prediction of clinical outcome by myocardial CT perfusion in patients with low-risk unstable angina pectoris.

    Science.gov (United States)

    Linde, Jesper J; Sørgaard, Mathias; Kühl, Jørgen T; Hove, Jens D; Kelbæk, Henning; Nielsen, Walter B; Kofoed, Klaus F

    2017-02-01

    The prognostic implications of myocardial computed tomography perfusion (CTP) analyses are unknown. In this sub-study to the CATCH-trial we evaluate the ability of adenosine stress CTP findings to predict mid-term major adverse cardiac events (MACE). In 240 patients with acute-onset chest pain, yet normal electrocardiograms and troponins, a clinically blinded adenosine stress CTP scan was performed in addition to conventional diagnostic evaluation. A reversible perfusion defect (PD) was found in 38 patients (16 %) and during a median follow-up of 19 months (range 12-22 months) 25 patients (10 %) suffered a MACE (cardiac death, non-fatal myocardial infarction and revascularizations). Accuracy for the prediction of MACE expressed as the area under curve (AUC) on receiver-operating characteristic curves was 0.88 (0.83-0.92) for visual assessment of a PD and 0.80 (0.73-0.85) for stress TPR (transmural perfusion ratio). After adjustment for the pretest probability of obstructive coronary artery disease, both detection of a PD and stress TPR were significantly associated with MACE with an adjusted hazard ratio of 39 (95 % confidence interval 11-134), p 10 % of the LV myocardium had a worse prognosis compared to patients with a PD covering <10 % of the LV myocardium, p = 0.0002. The optimal cut-off value of the myocardial PD extent to predict MACE was 5.3 % of the left ventricle [sensitivity 84 % (64-96), specificity 95 % (91-97)]. Myocardial CT perfusion parameters predict mid-term clinical outcome in patients with recent acute-onset chest pain.

  11. Dual-energy CT perfusion and angiography in chronic thromboembolic pulmonary hypertension: diagnostic accuracy and concordance with radionuclide scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Dournes, Gael; Verdier, Damien; Montaudon, Michel; Laurent, Francois; Lederlin, Mathieu [Hopital Haut-Leveque, CHU Bordeaux, Department of Medical Imaging, Pessac (France); University Bordeaux Segalen, Bordeaux Cedex (France); Bullier, Eric; Riviere, Annalisa [Hopital Haut-Leveque, CHU Bordeaux, Department of Nuclear Medicine, Pessac (France); Dromer, Claire [Hopital Haut-Leveque, CHU Bordeaux, Department of Respiratory Diseases, Pessac (France); Picard, Francois [Hopital Haut-Leveque, CHU Bordeaux, Department of Cardiology, Pessac (France); Billes, Marc-Alain [Hopital Haut-Leveque, CHU Bordeaux, Department of Cardiac Surgery, Pessac (France); Corneloup, Olivier [Hopital Haut-Leveque, CHU Bordeaux, Department of Medical Imaging, Pessac (France)

    2014-01-15

    To evaluate the diagnostic accuracy of dual-energy computed tomography (DECT) perfusion and angiography versus ventilation/perfusion (V/Q) scintigraphy in chronic thromboembolic pulmonary hypertension (CTEPH), and to assess the per-segment concordance rate of DECT and scintigraphy. Forty consecutive patients with proven pulmonary hypertension underwent V/Q scintigraphy and DECT perfusion and angiography. Each imaging technique was assessed for the location of segmental defects. Diagnosis of CTEPH was established when at least one segmental perfusion defect was detected by scintigraphy. Diagnostic accuracy of DECT perfusion and angiography was assessed and compared with scintigraphy. In CTEPH patients, the per-segment concordance between scintigraphy and DECT perfusion/angiography was calculated. Fourteen patients were diagnosed with CTEPH and 26 with other aetiologies. DECT perfusion and angiography correctly identified all CTEPH patients with sensitivity/specificity values of 1/0.92 and 1/0.93, respectively. At a segmental level, DECT perfusion showed moderate agreement (κ = 0.44) with scintigraphy. Agreement between CT angiography and scintigraphy ranged from fair (κ = 0.31) to slight (κ = 0.09) depending on whether completely or partially occlusive patterns were considered, respectively. Both DECT perfusion and angiography show satisfactory performance for the diagnosis of CTEPH. DECT perfusion is more accurate than angiography at identifying the segmental location of abnormalities. (orig.)

  12. Dual-energy CT perfusion and angiography in chronic thromboembolic pulmonary hypertension: diagnostic accuracy and concordance with radionuclide scintigraphy

    International Nuclear Information System (INIS)

    Dournes, Gael; Verdier, Damien; Montaudon, Michel; Laurent, Francois; Lederlin, Mathieu; Bullier, Eric; Riviere, Annalisa; Dromer, Claire; Picard, Francois; Billes, Marc-Alain; Corneloup, Olivier

    2014-01-01

    To evaluate the diagnostic accuracy of dual-energy computed tomography (DECT) perfusion and angiography versus ventilation/perfusion (V/Q) scintigraphy in chronic thromboembolic pulmonary hypertension (CTEPH), and to assess the per-segment concordance rate of DECT and scintigraphy. Forty consecutive patients with proven pulmonary hypertension underwent V/Q scintigraphy and DECT perfusion and angiography. Each imaging technique was assessed for the location of segmental defects. Diagnosis of CTEPH was established when at least one segmental perfusion defect was detected by scintigraphy. Diagnostic accuracy of DECT perfusion and angiography was assessed and compared with scintigraphy. In CTEPH patients, the per-segment concordance between scintigraphy and DECT perfusion/angiography was calculated. Fourteen patients were diagnosed with CTEPH and 26 with other aetiologies. DECT perfusion and angiography correctly identified all CTEPH patients with sensitivity/specificity values of 1/0.92 and 1/0.93, respectively. At a segmental level, DECT perfusion showed moderate agreement (κ = 0.44) with scintigraphy. Agreement between CT angiography and scintigraphy ranged from fair (κ = 0.31) to slight (κ = 0.09) depending on whether completely or partially occlusive patterns were considered, respectively. Both DECT perfusion and angiography show satisfactory performance for the diagnosis of CTEPH. DECT perfusion is more accurate than angiography at identifying the segmental location of abnormalities. (orig.)

  13. CT Perfusion for Early Response Evaluation of Radiofrequency Ablation of Focal Liver Lesions: First Experience

    Energy Technology Data Exchange (ETDEWEB)

    Marquez, Herman P., E-mail: hermanpaulo.marquezmasquiaran@usz.ch; Puippe, Gilbert; Mathew, Rishi Philip; Alkadhi, Hatem; Pfammatter, Thomas; Fischer, Michael A. [University Hospital Zurich, Department of Diagnostic and Interventional Radiology, Institute of Diagnostic and Interventional Radiology (Switzerland)

    2017-01-15

    PurposeTo investigate the value of perfusion CT (P-CT) for early assessment of treatment response in patients undergoing radiofrequency ablation (RFA) of focal liver lesions.Methods and Materials20 consecutive patients (14 men; mean age 64 ± 14) undergoing P-CT within 24 h after RFA of liver metastases (n = 10) or HCC (n = 10) were retrospectively included. Two readers determined arterial liver perfusion (ALP, mL/min/100 mL), portal liver perfusion (PLP, mL/min/100 mL), and hepatic perfusion index (HPI, %) in all post-RFA lesions by placing a volume of interest in the necrotic central (CZ), the transition (TZ), and the surrounding parenchymal (PZ) zone. Patients were classified into complete responders (no residual tumor) and incomplete responders (residual/progressive tumor) using imaging follow-up with contrast-enhanced CT or MRI after a mean of 57 ± 30 days. Prediction of treatment response was evaluated using the area under the curve (AUC) from receiver operating characteristic analysis.ResultsMean ALP/PLP/HPI of both readers were 4.8/15.4/61.2 for the CZ, 9.9/16.8/66.3 for the TZ and 20.7/29.0/61.8 for the PZ. Interreader agreement of HPI was fair for the CZ (intraclass coefficient 0.713), good for the TZ (0.813), and excellent for the PZ (0.920). For both readers, there were significant differences in HPI of the CZ and TZ between responders and nonresponders (both, P < 0.05). HPI of the TZ showed the highest AUC (0.911) for prediction of residual tumor, suggesting a cut-off value of 76 %.ConclusionIncreased HPI of the transition zone assessed with P-CT after RFA might serve as an early quantitative biomarker for residual tumor in patients with focal liver lesions.

  14. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    International Nuclear Information System (INIS)

    Mendrik, Adrienne M; Van Ginneken, Bram; Viergever, Max A; Vonken, Evert-jan; De Jong, Hugo W; Riordan, Alan; Van Seeters, Tom; Smit, Ewoud J; Prokop, Mathias

    2011-01-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  15. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    Energy Technology Data Exchange (ETDEWEB)

    Mendrik, Adrienne M; Van Ginneken, Bram; Viergever, Max A [Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands); Vonken, Evert-jan; De Jong, Hugo W; Riordan, Alan; Van Seeters, Tom; Smit, Ewoud J; Prokop, Mathias, E-mail: a.m.mendrik@gmail.com [Radiology Department, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)

    2011-07-07

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  16. Hepatic perfusion disorders: a pictorial review of CT and MR imaging

    International Nuclear Information System (INIS)

    Yim, Nam Yeol; Jeong, Yong Yeon; Shin, Sang Soo; Song, Sang Gook; Lim, Hyo Soon; Heo, Suk Hee; Chang, Nam Kyu; Yoon, Woong; Kang, Heoung Keun; Lan, Shen Yu

    2005-01-01

    The liver has a unique dual blood supply through the portal vein and the hepatic artery. There are several communications between these two vessels under various conditions such as in hepatic tumors, trauma and liver cirrhosis, vascular compromise, among others. When vascular compromise occurs, this dual blood supply system can cause changes in the volume of blood flow in individual vessels or even in the direction of blood flow. With rapid image acquisition and increased resolution available in multislice CT and MR imaging, hepatic perfusion disorders are now more frequently encountered than in the past. Familiarity with imaging findings of these perfusion disorders will be helpful in characterizing focal hepatic lesions and will also help to avoid false positive diagnoses

  17. Time separation technique: Accurate solution for 4D C-Arm-CT perfusion imaging using a temporal decomposition model.

    Science.gov (United States)

    Bannasch, Sebastian; Frysch, Robert; Pfeiffer, Tim; Warnecke, Gerald; Rose, Georg

    2018-03-01

    The issue of perfusion imaging using a temporal decomposition model is to enable the reconstruction of undersampled measurements acquired with a slowly rotating x-ray-based imaging system, for example, a C-arm-based cone beam computed tomography (CB-CT). The aim of this work is to integrate prior knowledge into the dynamic CT task in order to reduce the required number of views and the computational effort as well as to save dose. The prior knowledge comprises of a mathematical model and clinical perfusion data. In case of model-based perfusion imaging via superposition of specified orthogonal temporal basis functions, a priori knowledge is incorporated into the reconstructions. Instead of estimating the dynamic attenuation of each voxel by a weighting sum, the modeling approach is done as a preprocessing step in the projection space. This point of view provides a method that decomposes the temporal and spatial domain of dynamic CT data. The resulting projection set consists of spatial information that can be treated as individual static CT tasks. Consequently, the high-dimensional model-based CT system can be completely transformed, allowing for the use of an arbitrary reconstruction algorithm. For CT, reconstructions of preprocessed dynamic in silico data are illustrated and evaluated by means of conventional clinical parameters for stroke diagnostics. The time separation technique presented here, provides the expected accuracy of model-based CT perfusion imaging. Consequently, the model-based handled 4D task can be solved approximately as fast as the corresponding static 3D task. For C-arm-based CB-CT, the algorithm presented here provides a solution for resorting to model-based perfusion reconstruction without its connected high computational cost. Thus, this algorithm is potentially able to have recourse to the benefit from model-based perfusion imaging for practical application. This study is a proof of concept. © 2018 American Association of Physicists in

  18. CT perfusion mapping of hemodynamic disturbances associated to acute spontaneous intracerebral hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Fainardi, Enrico; Borrelli, Massimo; Saletti, Andrea; Ceruti, Stefano; Tamarozzi, Riccardo [Azienda Ospedaliera Universitaria, Neuroradiology Unit, Department of Neuroscience, Ferrara (Italy); Schivalocchi, Roberta; Cavallo, Michele [Azienda Ospedaliera Universitaria, Neurosurgery Unit, Department of Neuroscience, Ferrara (Italy); Azzini, Cristiano [Azienda Ospedaliera Universitaria, Neurology Unit, Department of Neuroscience, Ferrara (Italy); Chieregato, Arturo [Ospedale M. Bufalini, Neurocritical Care Unit, Cesena (Italy)

    2008-08-15

    We sought to quantify perfusion changes associated to acute spontaneous intracerebral hemorrhage (SICH) by means of computed tomography perfusion (CTP) imaging. We studied 89 patients with supratentorial SICH at admission CT by using CTP scanning obtained within 24 h after symptom onset. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV) and mean transit time (rMTT) levels were measured in four different regions of interest manually outlined on CT scan: (1) hemorrhagic core; (2) perihematomal low-density area; (3) 1 cm rim of normal-appearing brain tissue surrounding the perilesional area; and (4) a mirrored area, including the clot and the perihematomal region, located in the non-lesioned contralateral hemisphere. rCBF, rCBV, and rMTT mean levels showed a centrifugal distribution with a gradual increase from the core to the periphery (p < 0.0001). Perfusion absolute values were indicative of ischemia in hemorrhagic core, oligemia in perihematomal area, and hyperemia in normal-appearing and contralateral areas. Perihematomal rCBF and rCBV mean levels were higher in small ({<=}20 ml) than in large (>20 ml) hematomas (p<0.01 and p <0.02, respectively). Multi-parametric CTP mapping of acute SICH indicates that perfusion values show a progressive improvement from the core to the periphery. In the first 24 h, perihemorrhagic region was hypoperfused with CTP values which were not suggestive of ischemic penumbra destined to survive but more likely indicative of edema formation. These findings also argue for a potential influence of early amounts of bleeding on perihematomal hemodynamic abnormalities. (orig.)

  19. A comparative analysis of the dependences of the hemodynamic parameters on changes in ROI's position in perfusion CT scans

    Science.gov (United States)

    Choi, Yong-Seok; Cho, Jae-Hwan; Namgung, Jang-Sun; Kim, Hyo-Jin; Yoon, Dae-Young; Lee, Han-Joo

    2013-05-01

    This study performed a comparative analysis of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and mean time-to-peak (TTP) obtained by changing the region of interest's (ROI) anatomical positions, during CT brain perfusion. We acquired axial source images of perfusion CT from 20 patients undergoing CT perfusion exams due to brain trauma. Subsequently, the CBV, CBF, MTT, and TTP values were calculated through data-processing of the perfusion CT images. The color scales for the CBV, CBF, MTT, and TTP maps were obtained using the image data. Anterior cerebral artery (ACA) was taken as the standard ROI for the calculations of the perfusion values. Differences in the hemodynamic average values were compared in a quantitative analysis by placing ROI and the dividing axial images into proximal, middle, and distal segments anatomically. By performing the qualitative analysis using a blind test, we observed changes in the sensory characteristics by using the color scales of the CBV, CBF, and MTT maps in the proximal, middle, and distal segments. According to the qualitative analysis, no differences were found in CBV, CBF, MTT, and TTP values of the proximal, middle, and distal segments and no changes were detected in the color scales of the the CBV, CBF, MTT, and TTP maps in the proximal, middle, and distal segments. We anticipate that the results of the study will useful in assessing brain trauma patients using by perfusion imaging.

  20. Comparison between CT perfusion and Tc-99m ECD SPECT in the assessment of cerebrovascular reserve: a case study

    International Nuclear Information System (INIS)

    Crouch, J.; Wood, C.; Campbell, A.; McCarthy, M.; Dunne, M.; Bynevelt, M.; Lenzo, N.

    2003-01-01

    Full text: Brain perfusion is sensitively assessed by cerebral SPECT imaging utilising perfusion agents such as Tc-99m HMPAO and Tc-99m ethyl cysteinate dimer (ECD). Positron emission tomography can accurately assess and quantify brain perfusion and MRI can also be used for perfusion assessment. Both MRI and PET however are currently limited by cost and availability. A new technique utilising CT with contrast has been developed to assess and quantitate cerebral perfusion. The technique utilises arterial input information and deconvolution analysis to develop quantifiable measures of perfusion and contrast transit. The technique has been validated for acute stroke assessment and is being assessed for other possible applications. We present a case study comparison of this technique with cerebral SPECT perfusion using Tc-99m ECD in the assessment of cerebrovasular reserve. In each case, the CT and SPECT studies were performed pre- and post-acetazolamide and the SPECT study was statistically compared with a normal database utilising an automated brain perfusion statistical analysis package (NeurostatT). We discuss the correlation found between techniques, their strengths, weaknesses and possible future roles. Copyright (2003) The Australian and New Zealand Society of Nuclear Medicine Inc

  1. Perfusion CT Changes in Liver Metastases from Pancreatic Neuroendocrine Tumors During Everolimus Treatment.

    Science.gov (United States)

    D'Onofrio, Mirko; Cingarlini, Sara; Ortolani, Silvia; Crosara, Stefano; DE Robertis, Riccardo; Vallerio, Paola; Grego, Elisabetta; Ciaravino, Valentina; Ruzzenente, Andrea; Landoni, Luca; Scarpa, Aldo; Bassi, Claudio; Tortora, Giampaolo

    2017-03-01

    To evaluate modifications of perfusional parameters assessed by perfusion computed tomography (P-CT) of liver metastases (LM) from pancreatic neuroendocrine tumors (PanNETs) during everolimus treatment. All patients with LMs from G1-2 PanNETs undergoing everolimus treatment between January 2013 and January 2015 were prospectively evaluated with P-CT at baseline, and after 2 and 4 months of therapy. Size, perfusion, blood volume (BV), peak enhancement intensity (PEI) and time to peak for each lesion were calculated. A total of 33 LMs in nine patients with G1-2 PanNETs were prospectively evaluated: 23/33 (69.7%) were responders, 10/33 (30.3%) were non-responders. Among perfusional parameters, only numerical peak enhancement intensity values significantly differed between the two groups at baseline (p=0.043). BV increase was the most significant perfusional modification identifying responding lesions, even at an early stage of treatment, with a high positive predictive value (89.47%). P-CT seems to be useful for prediction of response to everolimus of LMs from PanNETs. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  2. Cerebral blood volume imaging by flat detector computed tomography in comparison to conventional multislice perfusion CT

    International Nuclear Information System (INIS)

    Struffert, Tobias; Kloska, Stephan; Engelhorn, Tobias; Doerfler, Arnd; Deuerling-Zheng, Yu; Boese, Jan; Zellerhoff, Michael; Schwab, Stefan

    2011-01-01

    We tested the hypothesis that Flat Detector computed tomography (FD-CT) with intravenous contrast medium would allow the calculation of whole brain cerebral blood volume (CBV) mapping (FD-CBV) and would correlate with multislice Perfusion CT (PCT). Twenty five patients were investigated with FD-CBV and PCT. Correlation of the CBV maps of both techniques was carried out with measurements from six anatomical regions from both sides of the brain. Mean values of each region and the correlation coefficient were calculated. Bland-Altman analysis was performed to compare the two different imaging techniques. The image and data quality of both PCT and FD-CBV were suitable for evaluation in all patients. The mean CBV values of FD-CBV and PCT showed only minimal differences with overlapping standard deviation. The correlation coefficient was 0.79 (p < 0.01). Bland-Altman analysis showed a mean difference of -0.077 ± 0.48 ml/100 g between FD-CBV and PCT CBV measurements, indicating that FD-CBV values were only slightly lower than those of PCT. CBV mapping with intravenous contrast medium using Flat Detector CT compared favourably with multislice PCT. The ability to assess cerebral perfusion within the angiographic suite may improve the management of ischaemic stroke and evaluation of the efficacy of dedicated therapies. (orig.)

  3. Adaptive statistical iterative reconstruction improves image quality without affecting perfusion CT quantitation in primary colorectal cancer

    Directory of Open Access Journals (Sweden)

    D. Prezzi

    Full Text Available Objectives: To determine the effect of Adaptive Statistical Iterative Reconstruction (ASIR on perfusion CT (pCT parameter quantitation and image quality in primary colorectal cancer. Methods: Prospective observational study. Following institutional review board approval and informed consent, 32 patients with colorectal adenocarcinoma underwent pCT (100 kV, 150 mA, 120 s acquisition, axial mode. Tumour regional blood flow (BF, blood volume (BV, mean transit time (MTT and permeability surface area product (PS were determined using identical regions-of-interests for ASIR percentages of 0%, 20%, 40%, 60%, 80% and 100%. Image noise, contrast-to-noise ratio (CNR and pCT parameters were assessed across ASIR percentages. Coefficients of variation (CV, repeated measures analysis of variance (rANOVA and Spearman’ rank order correlation were performed with statistical significance at 5%. Results: With increasing ASIR percentages, image noise decreased by 33% while CNR increased by 61%; peak tumour CNR was greater than 1.5 with 60% ASIR and above. Mean BF, BV, MTT and PS differed by less than 1.8%, 2.9%, 2.5% and 2.6% across ASIR percentages. CV were 4.9%, 4.2%, 3.3% and 7.9%; rANOVA P values: 0.85, 0.62, 0.02 and 0.81 respectively. Conclusions: ASIR improves image noise and CNR without altering pCT parameters substantially. Keywords: Perfusion imaging, Multidetector computed tomography, Colorectal neoplasms, Computer-assisted image processing, Radiation dosage

  4. Predictive Significance of Tumor Grade Using 256-Slice CT Whole-Tumor Perfusion Imaging in Colorectal Adenocarcinoma.

    Science.gov (United States)

    Xu, Yanyan; Sun, Hongliang; Song, Aiping; Yang, Qiang; Lu, Xiaomei; Wang, Wu

    2015-12-01

    The preoperative assessment of tumor grade has important clinical implications for the treatment and prognosis of patients with colorectal adenocarcinomas. The purpose of this study is to investigate the predictive significance of colorectal adenocarcinoma grade using 256-slice whole-tumor computed tomography (CT) perfusion. Fifty-three patients with proven colorectal adenocarcinomas were enrolled. All of them underwent 256-slice whole-tumor CT perfusion. They were divided into two different subgroups according to postoperative pathological results: low grade and high grade. The Kruskal-Wallis test or one-way analysis of variance was used for comparison of CT perfusion parameters between different tumor grades. Multivariant correlation between pathologic tumor stage, histologic tumor differentiation, and whole-tumor CT perfusion parameters was evaluated by Spearman rank correlation coefficient. According to receiver operating characteristic (ROC) curves, perfusion parameters including blood flow (BF), peak enhancement index (PEI), blood volume (BV), and time to peak (TTP) of 53 patients were analyzed, and the sensitivity, specificity, and accuracy of these parameters in predicting tumor grade were calculated. There were significant differences in BF and TTP between low-grade and high-grade tumors. According to the ROC curve, BF and TTP were of diagnostic significance, with the area under the curve values of 0.828 and 0.736, respectively. The diagnostic threshold of BF was 32.12 mL/min/100 g and that of TTP was 18.10 seconds. The CT perfusion parameters (BF, TTP) of first-pass 256-slice whole-tumor CT perfusion imaging can reflect tumor grade in colorectal adenocarcinoma. Copyright © 2015 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  5. Efficacy of superficial temporal artery-middle cerebral artery bypass in cerebrovascular steno-occlusive diseases: Hemodynamics assessed by perfusion computed tomography.

    Science.gov (United States)

    Kwon, Woo-Keun; Kwon, Taek-Hyun; Park, Dong-Hyuk; Kim, Joo-Han; Ha, Sung-Kon

    2017-01-01

    Our purpose of this study was to assess the cerebral hemodynamic improvement with perfusion computed tomography (CT), before and after superficial temporal artery (STA) to middle cerebral artery (MCA) bypass surgery in patients with cerebrovascular steno-occlusive diseases including both moyamoya disease and nonmoyamoya steno-occlusions. Twenty-four STA-MCA bypasses were performed to 22 patients with symptomatic cerebrovascular steno-occlusive diseases, including both moyamoya disease and nonmoyamoya steno-occlusive diseases. Brain perfusion CT images were obtained before and after the bypass surgery. The relative parameters such as cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) derived from the perfusion CT were collected and analyzed to assess the efficacy of STA-MCA bypass. The CBF increased, and MTT decreased after the bypass surgery in both moyamoya group and nonmoyamoya group. The increase of CBF in nonmoyamoya group and the decrease of MTT delay in moyamoya group, overall group were statistically significant ( P cerebrovascular steno-occlusive diseases, such as moyamoya disease and internal carotid artery/MCA steno-occlusion. And perfusion CT can be used as an effective quantitative modality to assess the cerebral perfusion before and after the STA-MCA bypass surgery.

  6. Perfusion CT of the brain in the assessment of flow alterations during brachytherapy of meningioma

    Energy Technology Data Exchange (ETDEWEB)

    Bondestam, S.; Halavaara, J.T.; Kinnunen, J.J. [Helsinki Univ. Central Hospital (Finland). Dept. of Diagnostic Radiology; Jaeaeskelaeinen, J.E. [Helsinki Univ. Central Hospital (Finland). Dept. of Neurosurgery; Hamberg, L.M. [Massachusetts General Hospital, Boston, MA (United States). Dept. of Radiology

    1999-09-01

    Purpose: The aim was to investigate the use of perfusion CT of the brain in the assessment of flow alterations during brachytherapy of meningiomas. Material and Methods: Six patients with an intracranialmeningioma were investigated during brachytherapy treatment by sterotactic implantation of I-125 seeds. Cerebral blood flow (CBF) in the tumour centre and the tumour periphery as well as in the normal brain parenchyma was determined by perfusion CT. Follow-up examinations were performed during the first year after the implantation. The CBF of the normal brain parenchyma was used as control. Results: In the beginning of therapy, the mean {+-}SEM blood flow in the tumour centre was 231.4{+-}58.1 ml/100 g/min and in the periphery 223.5{+-}53.8 ml/100 g/min. Within three months after the iodine seed implantation, the tumour blood flow had decreased 41%. At the one-year follow-up, the tumour blood flow in the centre had decreased to 68.7{+-}45.9 ml/100 g/min. In the periphery of the tumour, it remained nearly unchanged (199.3{+-}101.0 ml/100 g/min). The CBF values obtained form normal brain parenchyma did not decrease during the treatment. Throughout the study, the mean CBF for the normal grey matter was 38.5{+-}2.9 ml/100 g/min, and 22.3{+-}1.2 ml/100 g/min for the normal white matter. Conclusion: Perfusion CT seems to enable accurate monitoring of the blood flow of meningiomas during brachytherapy, and could be used in clinical situations where blood flow changes in brain and tumours should be investigated. (orig.)

  7. Classification of arterial and venous cerebral vasculature based on wavelet postprocessing of CT perfusion data.

    Science.gov (United States)

    Havla, Lukas; Schneider, Moritz J; Thierfelder, Kolja M; Beyer, Sebastian E; Ertl-Wagner, Birgit; Reiser, Maximilian F; Sommer, Wieland H; Dietrich, Olaf

    2016-02-01

    The purpose of this study was to propose and evaluate a new wavelet-based technique for classification of arterial and venous vessels using time-resolved cerebral CT perfusion data sets. Fourteen consecutive patients (mean age 73 yr, range 17-97) with suspected stroke but no pathology in follow-up MRI were included. A CT perfusion scan with 32 dynamic phases was performed during intravenous bolus contrast-agent application. After rigid-body motion correction, a Paul wavelet (order 1) was used to calculate voxelwise the wavelet power spectrum (WPS) of each attenuation-time course. The angiographic intensity A was defined as the maximum of the WPS, located at the coordinates T (time axis) and W (scale/width axis) within the WPS. Using these three parameters (A, T, W) separately as well as combined by (1) Fisher's linear discriminant analysis (FLDA), (2) logistic regression (LogR) analysis, or (3) support vector machine (SVM) analysis, their potential to classify 18 different arterial and venous vessel segments per subject was evaluated. The best vessel classification was obtained using all three parameters A and T and W [area under the curve (AUC): 0.953 with FLDA and 0.957 with LogR or SVM]. In direct comparison, the wavelet-derived parameters provided performance at least equal to conventional attenuation-time-course parameters. The maximum AUC obtained from the proposed wavelet parameters was slightly (although not statistically significantly) higher than the maximum AUC (0.945) obtained from the conventional parameters. A new method to classify arterial and venous cerebral vessels with high statistical accuracy was introduced based on the time-domain wavelet transform of dynamic CT perfusion data in combination with linear or nonlinear multidimensional classification techniques.

  8. Reproducibility of CT Perfusion Parameters in Liver Tumors and Normal Liver

    Science.gov (United States)

    Ng, Chaan S.; Chandler, Adam G.; Wei, Wei; Herron, Delise H.; Anderson, Ella F.; Kurzrock, Razelle; Charnsangavej, Chusilp

    2011-01-01

    Purpose: To assess the reproducibility of computed tomographic (CT) perfusion measurements in liver tumors and normal liver and effects of motion and data acquisition time on parameters. Materials and Methods: Institutional review board approval and written informed consent were obtained for this prospective study. The study complied with HIPAA regulations. Two CT perfusion scans were obtained 2–7 days apart in seven patients with liver tumors with two scanning phases (phase 1: 30-second breath-hold cine; phase 2: six intermittent free-breathing cines) spanning 135 seconds. Blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability–surface area product (PS) for tumors and normal liver were calculated from phase 1 with and without rigid registration and, for combined phases 1 and 2, with manually and rigid-registered phase 2 images, by using deconvolution modeling. Variability was assessed with within-patient coefficients of variation (CVs) and Bland-Altman analyses. Results: For tumors, BF, BV, MTT, and PS values and reproducibility varied by analytical method, the former by up to 11%, 23%, 21%, and 138%, respectively. Median PS values doubled with the addition of phase 2 data to phase 1 data. The best overall reproducibility was obtained with rigidly registered phase 1 and phase 2 images, with within-patient CVs for BF, BV, MTT, and PS of 11.2%, 14.4%, 5.5% and 12.1%, respectively. Normal liver evaluations were similar, except with marginally lower variability. Conclusion: Absolute values and reproducibility of CT perfusion parameters were markedly influenced by motion and data acquisition time. PS, in particular, probably requires data acquisition beyond a single breath hold, for which motion-correction techniques are likely necessary. © RSNA, 2011 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11110331/-/DC1 PMID:21788525

  9. Direct myocardial perfusion imaging in valvular heart disease

    International Nuclear Information System (INIS)

    Soto, R.C.; Durante, M.L.; Villacorta, E.V.; Torres, J.F.; Monzon, O.P.

    1981-01-01

    Twenty two patients with rheumatic valvular heart disease - 21 having a history of heart failure - were studied using direct coronary injection of sup(99m)Tc labelled MAA particles during the course of hemodynamic and arteriographic studies. Myocardial perfusion deficit patterns have been shown to be consistent or indicative of either patchy, regional or gross ischemia. In patients with history of documented heart failure 90% (18 cases) had ischemic perfusion deficit in the involved ventricle. We conclude that diminished myocardial blood flow is an important mechanism contributing to the development of heart failure. (orig.) [de

  10. Kombineret ventilations/perfusions-SPECT/CT er bedst til diagnostik af lungeemboli

    DEFF Research Database (Denmark)

    Gutte Borgwardt, Henrik; Mortensen, Jann; Kristoffersen, Ulrik Sloth

    2012-01-01

    The diagnosis of pulmonary embolism (PE) is usually established by a combination of clinical assessment, D-dimer test and imaging with either lung scintigraphy or pulmonary multidetector computed tomography angiography (CTA). Which of the two methods to use in PE diagnostic has not been determined...... and very limited data comparing these modalities are available. With the use of hybrid scanners, ventilation/perfusion-single-photon-emission-tomography (V/Q-SPECT) in combination with low-dose CT without contrast enhancement is feasible and should probably be considered first-line imaging in diagnosing PE....

  11. Noise characteristics of CT perfusion imaging: how does noise propagate from source images to final perfusion maps?

    Science.gov (United States)

    Li, Ke; Chen, Guang-Hong

    2016-03-01

    Cerebral CT perfusion (CTP) imaging is playing an important role in the diagnosis and treatment of acute ischemic strokes. Meanwhile, the reliability of CTP-based ischemic lesion detection has been challenged due to the noisy appearance and low signal-to-noise ratio of CTP maps. To reduce noise and improve image quality, a rigorous study on the noise transfer properties of CTP systems is highly desirable to provide the needed scientific guidance. This paper concerns how noise in the CTP source images propagates to the final CTP maps. Both theoretical deviations and subsequent validation experiments demonstrated that, the noise level of background frames plays a dominant role in the noise of the cerebral blood volume (CBV) maps. This is in direct contradiction with the general belief that noise of non-background image frames is of greater importance in CTP imaging. The study found that when radiation doses delivered to the background frames and to all non-background frames are equal, lowest noise variance is achieved in the final CBV maps. This novel equality condition provides a practical means to optimize radiation dose delivery in CTP data acquisition: radiation exposures should be modulated between background frames and non-background frames so that the above equality condition is satisïnAed. For several typical CTP acquisition protocols, numerical simulations and in vivo canine experiment demonstrated that noise of CBV can be effectively reduced using the proposed exposure modulation method.

  12. Effects of Radiation Exposure on the Cost-Effectiveness of CT Angiography and Perfusion Imaging in Aneurysmal Subarachnoid Hemorrhage.

    Science.gov (United States)

    Ivanidze, J; Charalel, R A; Shuryak, I; Brenner, D; Pandya, A; Kallas, O N; Kesavabhotla, K; Segal, A Z; Simon, M S; Sanelli, P C

    2017-03-01

    CT angiography and perfusion imaging is an important prognostic tool in the management of patients with aneurysmal subarachnoid hemorrhage. The purpose of this study was to perform a cost-effectiveness analysis of advanced imaging in patients with SAH, incorporating the risks of radiation exposure from CT angiography and CT perfusion imaging. The risks of radiation-induced brain cancer and cataracts were incorporated into our established decision model comparing the cost-effectiveness of CT angiography and CT perfusion imaging and transcranial Doppler sonography in SAH. Cancer risk was calculated by using National Cancer Institute methodology. The remaining input probabilities were based on literature data and a cohort at our institution. Outcomes were expected quality-adjusted life years gained, costs, and incremental cost-effectiveness ratios. One-way, 2-way, and probabilistic sensitivity analyses were performed. CT angiography and CT perfusion imaging were the dominant strategies, resulting in both better health outcomes and lower costs, even when incorporating brain cancer and cataract risks. Our results remained robust in 2-way sensitivity analyses varying the prolonged latency period up to 30 years, with either brain cancer risk up to 50 times higher than the upper 95% CI limit or the probability of cataracts from 0 to 1. Results were consistent for scenarios that considered either symptomatic or asymptomatic patients with SAH. Probabilistic sensitivity analysis confirmed our findings over a broad range of selected input parameters. While risks of radiation exposure represent an important consideration, CT angiography and CT perfusion imaging remained the preferred imaging compared with transcranial Doppler sonography in both asymptomatic and symptomatic patients with SAH, with improved health outcomes and lower health care costs, even when modeling a significantly higher risk and shorter latency period for both cataract and brain cancer than that currently

  13. Assessment of perfusion pattern and extent of perfusion defect on dual-energy CT angiography: Correlation between the causes of pulmonary hypertension and vascular parameters

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Young [Dept. of Radiology, Chonbuk National University Medical School and Hospital, Research Institute of Clinical Medicine, Jeonju (Korea, Republic of); Seo, Joon Beom; Oh, Sang Young; Lee, Choong Wook; Lee, Sang Min [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Hwang, Hye Jeon [Dept. of Radiology, Hallym University College of Medicine, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Lee, Young Kyung [Dept. of Radiology, Seoul Medical Center, Seoul (Korea, Republic of)

    2014-04-15

    To assess perfusion patterns on a dual-energy pulmonary CT angiography (DECTA) of pulmonary hypertension (PHT) with variable causes and to assess whether the extent of perfusion defect can be used in the severity assessment of PHT. Between March 2007 and February 2011, DECTA scans of 62 consecutive patients (24 men, 38 women; mean age, 58.5 ± 17.3 [standard deviation] years; range, 19-87 years) with PHT were retrospectively included with following inclusion criteria; 1) absence of acute pulmonary thromboembolism, 2) maximal velocity of tricuspid regurgitation jet (TR Vmax) above 3 m/s on echocardiography performed within one week of the DECTA study. Perfusion patterns of iodine map were divided into normal (NL), diffuse heterogeneously decreased (DH), multifocal geographic and multiple peripheral wedging patterns. The extent of perfusion defects (PD), the diameter of main pulmonary artery (MPA) and the ratio of ascending aorta diameter/MPA (aortopulmonary ratio, APR) were measured. Pearson correlation analysis was performed between TR Vmax on echocardiography and CT imaging parameters. Common perfusion patterns of primary PHT were DH (n = 15) and NL (n = 12). The perfusion patterns of secondary PHT were variable. On the correlation analysis, in primary PHT, TR Vmax significantly correlated with PD, MPA and APR (r = 0.52, r = 0.40, r = -0.50, respectively, all p < 0.05). In secondary PHT, TR Vmax significantly correlated with PD and MPA (r = 0.38, r = 0.53, respectively, all p < 0.05). Different perfusion patterns are observed on DECTA of PHT according to the causes. PD and MPA are significantly correlated with the TR Vmax.

  14. Fusion of CT coronary angiography and whole-heart dynamic 3D cardiac MR perfusion: building a framework for comprehensive cardiac imaging.

    Science.gov (United States)

    von Spiczak, Jochen; Manka, Robert; Gotschy, Alexander; Oebel, Sabrina; Kozerke, Sebastian; Hamada, Sandra; Alkadhi, Hatem

    2018-04-01

    The purpose of this work was to develop a framework for 3D fusion of CT coronary angiography (CTCA) and whole-heart dynamic 3D cardiac magnetic resonance perfusion (3D-CMR-Perf) image data-correlating coronary artery stenoses to stress-induced myocardial perfusion deficits for the assessment of coronary artery disease (CAD). Twenty-three patients who underwent CTCA and 3D-CMR-Perf for various indications were included retrospectively. For CTCA, image quality and coronary diameter stenoses > 50% were documented. For 3D-CMR-Perf, image quality and stress-induced perfusion deficits were noted. A software framework was developed to allow for 3D image fusion of both datasets. Computation steps included: (1) fully automated segmentation of coronary arteries and heart contours from CT; (2) manual segmentation of the left ventricle in 3D-CMR-Perf images; (3) semi-automatic co-registration of CT/CMR datasets; (4) projection of the 3D-CMR-Perf values on the CT left ventricle. 3D fusion analysis was compared to separate inspection of CTCA and 3D-CMR-Perf data. CT and CMR scans resulted in an image quality being rated as good to excellent (mean scores 3.5 ± 0.5 and 3.7 ± 0.4, respectively, scale 1-4). 3D-fusion was feasible in all 23 patients, and perfusion deficits could be correlated to culprit coronary lesions in all but one case (22/23 = 96%). Compared to separate analysis of CT and CMR data, coronary supply territories of 3D-CMR-Perf perfusion deficits were refined in two cases (2/23 = 9%), and the relevance of stenoses in CTCA was re-judged in four cases (4/23 = 17%). In conclusion, 3D fusion of CTCA/3D-CMR-Perf facilitates anatomic correlation of coronary lesions and stress-induced myocardial perfusion deficits thereby helping to refine diagnostic assessment of CAD.

  15. Effects of radiation dose reduction in Volume Perfusion CT imaging of acute ischemic stroke

    International Nuclear Information System (INIS)

    Othman, Ahmed E.; Brockmann, Carolin; Afat, Saif; Pjontek, Rastislav; Nikobashman, Omid; Brockmann, Marc A.; Wiesmann, Martin; Yang, Zepa; Kim, Changwon; Kim, Jong Hyo

    2015-01-01

    To examine the influence of radiation dose reduction on image quality and sensitivity of Volume Perfusion CT (VPCT) maps regarding the detection of ischemic brain lesions. VPCT data of 20 patients with suspected ischemic stroke acquired at 80 kV and 180 mAs were included. Using realistic reduced-dose simulation, low-dose VPCT datasets with 144 mAs, 108 mAs, 72 mAs and 36 mAs (80 %, 60 %, 40 % and 20 % of the original levels) were generated, resulting in a total of 100 datasets. Perfusion maps were created and signal-to-noise-ratio (SNR) measurements were performed. Qualitative analyses were conducted by two blinded readers, who also assessed the presence/absence of ischemic lesions and scored CBV and CBF maps using a modified ASPECTS-score. SNR of all low-dose datasets were significantly lower than those of the original datasets (p <.05). All datasets down to 72 mAs (40 %) yielded sufficient image quality and high sensitivity with excellent inter-observer-agreements, whereas 36 mAs datasets (20 %) yielded poor image quality in 15 % of the cases with lower sensitivity and inter-observer-agreements. Low-dose VPCT using decreased tube currents down to 72 mAs (40 % of original radiation dose) produces sufficient perfusion maps for the detection of ischemic brain lesions. (orig.)

  16. Effects of radiation dose reduction in Volume Perfusion CT imaging of acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Othman, Ahmed E. [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Eberhard Karls University Tuebingen, University Hospital Tuebingen, Department for Diagnostic and Interventional Radiology, Tuebingen (Germany); Brockmann, Carolin; Afat, Saif; Pjontek, Rastislav; Nikobashman, Omid; Brockmann, Marc A.; Wiesmann, Martin [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Yang, Zepa; Kim, Changwon [Seoul National University, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Suwon (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Kim, Jong Hyo [Seoul National University, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Suwon (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Center for Medical-IT Convergence Technology Research, Advanced Institute of Convergence Technology, Suwon (Korea, Republic of)

    2015-12-15

    To examine the influence of radiation dose reduction on image quality and sensitivity of Volume Perfusion CT (VPCT) maps regarding the detection of ischemic brain lesions. VPCT data of 20 patients with suspected ischemic stroke acquired at 80 kV and 180 mAs were included. Using realistic reduced-dose simulation, low-dose VPCT datasets with 144 mAs, 108 mAs, 72 mAs and 36 mAs (80 %, 60 %, 40 % and 20 % of the original levels) were generated, resulting in a total of 100 datasets. Perfusion maps were created and signal-to-noise-ratio (SNR) measurements were performed. Qualitative analyses were conducted by two blinded readers, who also assessed the presence/absence of ischemic lesions and scored CBV and CBF maps using a modified ASPECTS-score. SNR of all low-dose datasets were significantly lower than those of the original datasets (p <.05). All datasets down to 72 mAs (40 %) yielded sufficient image quality and high sensitivity with excellent inter-observer-agreements, whereas 36 mAs datasets (20 %) yielded poor image quality in 15 % of the cases with lower sensitivity and inter-observer-agreements. Low-dose VPCT using decreased tube currents down to 72 mAs (40 % of original radiation dose) produces sufficient perfusion maps for the detection of ischemic brain lesions. (orig.)

  17. Cystic thymic diseases: CT manifestations

    Energy Technology Data Exchange (ETDEWEB)

    Song, Soon Young; Choi, Yo Won; Jeon, Eui Yong; Jeon, Seok Chol; Seo, Heung Suk; Hahm, Chang Kok [School of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1995-09-15

    To describe CT findings and differential points of cystic thymic lesions. We evaluated retrospectively total 19 masses with well marginated cystic lesions at thymic area on CT scans. They were 10 teratomas, 3 congenital thymic cysts, 2 multilocular thymic cysts(associated with thymoma and myasthenia gravis in each), 2 cysts Assciated with thymic Hodgkin's lymphomas an ectopic parathyroid cyst, and an infected thymic cyst. The radiological abnormalities evaluated were thickness of the wall, presence or abscene of septa, mural nodule, solid component, calcification and fat component. All three cases of congenital thymic cysts and an ectopic parathyroid cyst appeared as thin-walled unilocular cyst with homogeneous internal density and without identifiable solid component. In multilocular thymic cyst, there were thick wall and solid components(n =2), thick internal septa and calcifications(n = 1). The cysts of teratomas manifested thick walls(n = 9), internal septa(n = 4), calcifications(n = 6), fat components(n = 4), and solid components(n = 4). Cysts in Hodgkin's diseases appeared as multilocular or unilocular and had thick wall and septa without calcification. Infected thymic cyst presented with multilocular cystic mass with identifiable wall and septa, calcification, and solid components. The thymic diseases with cystic lesion include teratomas, congenital thymic cysts, multilocular thymic cysts, parathyroid cyst, and Hodgkin's disease. Congenital thymic cyst and ectopic parathyroid cyst are thin-walled unilocular cystic lesions. Cystic lesions associated with teratoma, Hodgkin's disease, and multilocular thymic cyst are thick-walled cystic lesions with or without solid component.

  18. The value of 64-slice spiral CT perfusion imaging in the treatment of liver cancer with argon-helium cryoablation.

    Science.gov (United States)

    Lv, Yinggang; Jin, Yurong; Yan, Qiaohuan; Yuan, Dingling; Wang, Yanling; Li, Xianping; Shen, Yanfeng

    2016-12-01

    We analyzed the effectiveness of using 64-slice spiral computed tomography (CT) and perfusion imaging to guide argon-helium cryoablation treatment of liver cancer. In total, 60 cases of advanced hepatocellular carcinoma before surgery treated with argon-helium cryoablation were inlcuded in the present study. Retrospective summary of the 60 cases of metaphase and advanced liver cancer were used as the control group. The control group were treated using cryoablation with argon-helium knife. We used enhanced scanning with 64-slice spiral CT to define the extent of their lesions and prepared a plan of percutaneous cryoablation for the treatment. Intraoperatively, we used the dynamics of CT perfusion imaging to observe the frozen ablation range and decreased the rate of complications. After surgery, the patients were followed-up regularly by 64-slice CT. We used conventional X-ray, CT and magnetic resonance imaging (MRI) for pre-operative lateralization. Intraoperative X-ray or ultrasound guidance and follow-up with CT or MTI were added to determine the clinical effectiveness and prognosis. The results showed that the total effective rate was improved significantly and incidence rate of overall complications decreased markedly in the observation group. Following treatment, AFP decreased significantly while the total freezing area and time were reduced significantly. The median survival time was increased significantly in the observation group. The numeric values of hepatic arterial perfusion, portal vein perfusion and hepatic arterial perfusion index were all markedly lowered after treatment. Differences were statistically significant (PCT perfusion imaging may considerably improve the effects of liver cancer treatment using the argon-helium cryoablation. It extended the survival time and reduced complications.

  19. Static Myocardial Perfusion Imaging using denoised dynamic Rb-82 PET/CT scans

    DEFF Research Database (Denmark)

    Petersen, Maiken N.M.; Hoff, Camilla; Harms, Hans

    Introduction: Relative and absolute measures of myocardial perfusion are derived from a single 82Rb PET/CT scan. However, images are inherently noising due to the short half-life of 82Rb. We have previously shown that denoising techniques can be applied to dynamic 82Rb series with excellent...... quantitative accuracy. In this study, we examine static images created by summing late frames of denoised dynamic series. Method: 47 random clinical 82Rb stress and rest scans (27 male, age 68+/- 12 y., BMI 27.9 +/- 5.5 kg/m2) performed on a GE Discovery 690 PET/CT scanner were included in the study....... Administered 82Rb dose was 1110 MBq. Denoising using HYPR-LR or Hotelling 3D algorithms was performed as post-processing on the dynamic images series. Static series were created by summing frames from 2.5-5 min. The image data was analysed in QPET (Cedars-Sinai). Relative segmental perfusion (normalized...

  20. 3D movement correction of CT brain perfusion image data of patients with acute ischemic stroke

    International Nuclear Information System (INIS)

    Fahmi, Fahmi; Marquering, Henk A.; Streekstra, Geert J.; Borst, Jordi; Beenen, Ludo F.M.; Majoie, Charles B.L.; Niesten, Joris M.; Velthuis, Birgitta K.; VanBavel, Ed

    2014-01-01

    Head movement during CT brain perfusion (CTP) acquisition can deteriorate the accuracy of CTP analysis. Most CTP software packages can only correct in-plane movement and are limited to small ranges. The purpose of this study is to validate a novel 3D correction method for head movement during CTP acquisition. Thirty-five CTP datasets that were classified as defective due to head movement were included in this study. All CTP time frames were registered with non-contrast CT data using a 3D rigid registration method. Location and appearance of ischemic area in summary maps derived from original and registered CTP datasets were qualitative compared with follow-up non-contrast CT. A quality score (QS) of 0 to 3 was used to express the degree of agreement. Furthermore, experts compared the quality of both summary maps and assigned the improvement score (IS) of the CTP analysis, ranging from -2 (much worse) to 2 (much better). Summary maps generated from corrected CTP significantly agreed better with appearance of infarct on follow-up CT with mean QS 2.3 versus mean QS 1.8 for summary maps from original CTP (P = 0.024). In comparison to original CTP data, correction resulted in a quality improvement with average IS 0.8: 17 % worsened (IS = -2, -1), 20 % remained unchanged (IS = 0), and 63 % improved (IS = +1, +2). The proposed 3D movement correction improves the summary map quality for CTP datasets with severe head movement. (orig.)

  1. 3D movement correction of CT brain perfusion image data of patients with acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Fahmi, Fahmi [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); University of Sumatera Utara, Department of Electrical Engineering, Medan (Indonesia); Marquering, Henk A.; Streekstra, Geert J. [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Borst, Jordi; Beenen, Ludo F.M.; Majoie, Charles B.L. [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Niesten, Joris M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); VanBavel, Ed [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Collaboration: on behalf of the DUST study

    2014-06-15

    Head movement during CT brain perfusion (CTP) acquisition can deteriorate the accuracy of CTP analysis. Most CTP software packages can only correct in-plane movement and are limited to small ranges. The purpose of this study is to validate a novel 3D correction method for head movement during CTP acquisition. Thirty-five CTP datasets that were classified as defective due to head movement were included in this study. All CTP time frames were registered with non-contrast CT data using a 3D rigid registration method. Location and appearance of ischemic area in summary maps derived from original and registered CTP datasets were qualitative compared with follow-up non-contrast CT. A quality score (QS) of 0 to 3 was used to express the degree of agreement. Furthermore, experts compared the quality of both summary maps and assigned the improvement score (IS) of the CTP analysis, ranging from -2 (much worse) to 2 (much better). Summary maps generated from corrected CTP significantly agreed better with appearance of infarct on follow-up CT with mean QS 2.3 versus mean QS 1.8 for summary maps from original CTP (P = 0.024). In comparison to original CTP data, correction resulted in a quality improvement with average IS 0.8: 17 % worsened (IS = -2, -1), 20 % remained unchanged (IS = 0), and 63 % improved (IS = +1, +2). The proposed 3D movement correction improves the summary map quality for CTP datasets with severe head movement. (orig.)

  2. Comparison of quantitative myocardial perfusion imaging CT to fluorescent microsphere-based flow from high-resolution cryo-images

    Science.gov (United States)

    Eck, Brendan L.; Fahmi, Rachid; Levi, Jacob; Fares, Anas; Wu, Hao; Li, Yuemeng; Vembar, Mani; Dhanantwari, Amar; Bezerra, Hiram G.; Wilson, David L.

    2016-03-01

    Myocardial perfusion imaging using CT (MPI-CT) has the potential to provide quantitative measures of myocardial blood flow (MBF) which can aid the diagnosis of coronary artery disease. We evaluated the quantitative accuracy of MPI-CT in a porcine model of balloon-induced LAD coronary artery ischemia guided by fractional flow reserve (FFR). We quantified MBF at baseline (FFR=1.0) and under moderate ischemia (FFR=0.7) using MPI-CT and compared to fluorescent microsphere-based MBF from high-resolution cryo-images. Dynamic, contrast-enhanced CT images were obtained using a spectral detector CT (Philips Healthcare). Projection-based mono-energetic images were reconstructed and processed to obtain MBF. Three MBF quantification approaches were evaluated: singular value decomposition (SVD) with fixed Tikhonov regularization (ThSVD), SVD with regularization determined by the L-Curve criterion (LSVD), and Johnson-Wilson parameter estimation (JW). The three approaches over-estimated MBF compared to cryo-images. JW produced the most accurate MBF, with average error 33.3+/-19.2mL/min/100g, whereas LSVD and ThSVD had greater over-estimation, 59.5+/-28.3mL/min/100g and 78.3+/-25.6 mL/min/100g, respectively. Relative blood flow as assessed by a flow ratio of LAD-to-remote myocardium was strongly correlated between JW and cryo-imaging, with R2=0.97, compared to R2=0.88 and 0.78 for LSVD and ThSVD, respectively. We assessed tissue impulse response functions (IRFs) from each approach for sources of error. While JW was constrained to physiologic solutions, both LSVD and ThSVD produced IRFs with non-physiologic properties due to noise. The L-curve provided noise-adaptive regularization but did not eliminate non-physiologic IRF properties or optimize for MBF accuracy. These findings suggest that model-based MPI-CT approaches may be more appropriate for quantitative MBF estimation and that cryo-imaging can support the development of MPI-CT by providing spatial distributions of MBF.

  3. Co-registered perfusion SPECT/CT: Utility for prediction of improved postoperative outcome in lung volume reduction surgery candidates

    International Nuclear Information System (INIS)

    Takenaka, Daisuke; Ohno, Yoshiharu; Koyama, Hisanobu; Nogami, Munenobu; Onishi, Yumiko; Matsumoto, Keiko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

    2010-01-01

    Purpose: To directly compare the capabilities of perfusion scan, SPECT, co-registered SPECT/CT, and quantitatively and qualitatively assessed MDCT (i.e. quantitative CT and qualitative CT) for predicting postoperative clinical outcome for lung volume reduction surgery (LVRS) candidates. Materials and methods: Twenty-five consecutive candidates (19 men and six women, age range: 42-72 years) for LVRS underwent preoperative CT and perfusion scan with SPECT. Clinical outcome of LVRS for all subjects was also assessed by determining the difference between pre- and postoperative forced expiratory volume in 1 s (FEV 1 ) and 6-min walking distance (6MWD). All SPECT examinations were performed on a SPECT scanner, and co-registered to thin-section CT by using commercially available software. On planar imaging, SPECT and SPECT/CT, upper versus lower zone or lobe ratios (U/Ls) were calculated from regional uptakes between upper and lower lung fields in the operated lung. On quantitatively assessed CT, U/L for all subjects was assessed from regional functional lung volumes. On qualitatively assessed CT, planar imaging, SPECT and co-registered SPECT/CT, U/Ls were assessed with a 4-point visual scoring system. To compare capabilities of predicting clinical outcome, each U/L was statistically correlated with the corresponding clinical outcome. Results: Significantly fair or moderate correlations were observed between quantitatively and qualitatively assessed U/Ls obtained with all four methods and clinical outcomes (-0.60 ≤ r ≤ -0.42, p < 0.05). Conclusion: Co-registered perfusion SPECT/CT has better correlation with clinical outcome in LVRS candidates than do planar imaging, SPECT or qualitatively assessed CT, and is at least as valid as quantitatively assessed CT.

  4. Characteristics of images of angiographically proven normal coronary arteries acquired by adenosine-stress thallium-201 myocardial perfusion SPECT/CT-IQ[Symbol: see text]SPECT with CT attenuation correction changed stepwise.

    Science.gov (United States)

    Takahashi, Teruyuki; Tanaka, Haruki; Kozono, Nami; Tanakamaru, Yoshiki; Idei, Naomi; Ohashi, Norihiko; Ohtsubo, Hideki; Okada, Takenori; Yasunobu, Yuji; Kaseda, Shunichi

    2015-04-01

    Although several studies have shown the diagnostic and prognostic value of CT-based attenuation correction (AC) of single photon emission computed tomography (SPECT) images for diagnosing coronary artery disease (CAD), this issue remains a matter of debate. To clarify the characteristics of CT-AC SPECT images that might potentially improve diagnostic performance, we analyzed images acquired using adenosine-stress thallium-201 myocardial perfusion SPECT/CT equipped with IQ[Symbol: see text]SPECT (SPECT/CT-IQ[Symbol: see text]SPECT) from patients with angiographically proven normal coronary arteries after changing the CT attenuation correction (CT-AC) in a stepwise manner. We enrolled 72 patients (Male 36, Female 36) with normal coronary arteries according to findings of invasive coronary angiography or CT-angiography within three months after a SPECT/CT study. Projection images were reconstructed at CT-AC values of (-), 40, 60, 80 and 100 % using a CT number conversion program according to our definition and analyzed using polar maps according to sex. CT attenuation corrected segments were located from the mid- and apical-inferior spread through the mid- and apical-septal regions and finally to the basal-anterior and basal- and mid-lateral regions in males, and from the mid-inferior region through the mid-septal and mid-anterior, and mid-lateral regions in females as the CT-AC values increased. Segments with maximal mean counts shifted from the apical-anterior to mid-anterolateral region under both stress and rest conditions in males, whereas such segments shifted from the apical-septal to the mid-anteroseptal region under both stress and rest conditions in females. We clarified which part of the myocardium and to which degree CT-AC affects it in adenosine-stress thallium-201 myocardial perfusion SPECT/CT-IQ[Symbol: see text]SPECT images by changing the CT-AC value stepwise. We also identified sex-specific shifts of segments with maximal mean counts that changed as

  5. Diverticular disease in CT colonography

    International Nuclear Information System (INIS)

    Lefere, P.; Gryspeerdt, S.; Baekelandt, M.; Holsbeeck, B. van; Dewyspelaere, J.

    2003-01-01

    The aim of this study was to evaluate findings on CT colonography (CTC) in patients with diverticular disease. In a retrospective analysis of 160 consecutive patients, who underwent CTC and conventional colonoscopy (CC), patients with diverticular disease were retrieved. The CTC images were compared with CC and, if possible, with pathology. Findings on both 2D and 3D images are illustrated with emphasis on diagnostic problems and the possible solutions to overcome these problems. Several aspects of diverticulosis were detected: prediverticulosis (3%); global (55.6%); and focal wall thickening (4%) caused by thickened haustral folds, fibrosis, inflammation and adenocarcinoma; diverticula (52%); pseudopolypoid lesions caused by diverticular fecaliths (39%); inverted diverticula (1.2%); and mucosal prolapse (0.6%). Solutions to overcome pitfalls are described as abdominal windowing, content of the pseudopolypoid lesion, comparison of 2D and 3D images, prone-supine imaging and the aspect of the pericolic fat. In this series there were equivocal findings in case of mucosal prolapse (0.6%) and focal wall thickening (4%). Diverticulosis is a challenge for CTC to avoid false-positive diagnosis of polypoid and tumoral disease. Knowledge of possible false causes of polypoid disease and comparison of 2D and 3D images are necessary to avoid false-positive diagnosis. In case of equivocal findings additional conventional colonoscopy should be advised whenever a clinically significant lesion (≥1 cm) is suspected. (orig.)

  6. Diverticular disease in CT colonography

    Energy Technology Data Exchange (ETDEWEB)

    Lefere, P.; Gryspeerdt, S.; Baekelandt, M.; Holsbeeck, B. van [Dept. of Radiology, Roeselare (Belgium); Dewyspelaere, J. [Dept. of Gastroenterology, Roeselare (Belgium)

    2003-12-01

    The aim of this study was to evaluate findings on CT colonography (CTC) in patients with diverticular disease. In a retrospective analysis of 160 consecutive patients, who underwent CTC and conventional colonoscopy (CC), patients with diverticular disease were retrieved. The CTC images were compared with CC and, if possible, with pathology. Findings on both 2D and 3D images are illustrated with emphasis on diagnostic problems and the possible solutions to overcome these problems. Several aspects of diverticulosis were detected: prediverticulosis (3%); global (55.6%); and focal wall thickening (4%) caused by thickened haustral folds, fibrosis, inflammation and adenocarcinoma; diverticula (52%); pseudopolypoid lesions caused by diverticular fecaliths (39%); inverted diverticula (1.2%); and mucosal prolapse (0.6%). Solutions to overcome pitfalls are described as abdominal windowing, content of the pseudopolypoid lesion, comparison of 2D and 3D images, prone-supine imaging and the aspect of the pericolic fat. In this series there were equivocal findings in case of mucosal prolapse (0.6%) and focal wall thickening (4%). Diverticulosis is a challenge for CTC to avoid false-positive diagnosis of polypoid and tumoral disease. Knowledge of possible false causes of polypoid disease and comparison of 2D and 3D images are necessary to avoid false-positive diagnosis. In case of equivocal findings additional conventional colonoscopy should be advised whenever a clinically significant lesion ({>=}1 cm) is suspected. (orig.)

  7. Diverticular disease in CT colonography.

    Science.gov (United States)

    Lefere, Philippe; Gryspeerdt, Stefaan; Baekelandt, Marc; Dewyspelaere, Jef; van Holsbeeck, B

    2003-12-01

    The aim of this study was to evaluate findings on CT colonography (CTC) in patients with diverticular disease. In a retrospective analysis of 160 consecutive patients, who underwent CTC and conventional colonoscopy (CC), patients with diverticular disease were retrieved. The CTC images were compared with CC and, if possible, with pathology. Findings on both 2D and 3D images are illustrated with emphasis on diagnostic problems and the possible solutions to overcome these problems. Several aspects of diverticulosis were detected: prediverticulosis (3%); global (55.6%); and focal wall thickening (4%) caused by thickened haustral folds, fibrosis, inflammation and adenocarcinoma; diverticula (52%); pseudopolypoid lesions caused by diverticular fecaliths (39%); inverted diverticula (1.2%); and mucosal prolapse (0.6%). Solutions to overcome pitfalls are described as abdominal windowing, content of the pseudopolypoid lesion, comparison of 2D and 3D images, prone-supine imaging and the aspect of the pericolic fat. In this series there were equivocal findings in case of mucosal prolapse (0.6%) and focal wall thickening (4%). Diverticulosis is a challenge for CTC to avoid false-positive diagnosis of polypoid and tumoral disease. Knowledge of possible false causes of polypoid disease and comparison of 2D and 3D images are necessary to avoid false-positive diagnosis. In case of equivocal findings additional conventional colonoscopy should be advised whenever a clinically significant lesion (> or = 1 cm) is suspected.

  8. Estimation of Radiation Exposure of 128-Slice 4D-Perfusion CT for the Assessment of Tumor Vascularity

    International Nuclear Information System (INIS)

    Ketelsen, Dominik; Horger, Marius; Buchgeister, Markus; Fenchel, Michael; Thomas, Christoph; Boehringer, Nadine; Schulze, Maximilian; Tsiflikas, Ilias; Claussen, Claus D.; Heuschmid, Martin

    2010-01-01

    We aimed to estimate the effective dose of 4D-Perfusion-CT protocols of the lung, liver, and pelvis for the assessment of tumor vascularity. An Alderson-Rando phantom equipped with thermoluminescent dosimeters was used to determine the effective dose values of 4D Perfusion-CT. Phantom measurements were performed on a 128-slice single source scanner in adaptive 4D-spiral-mode with bidirectional table movement and a total scan range of 69 mm over a time period of nearly 120 seconds (26 scans). Perfusion measurements were simulated for the lung, liver, and pelvis under the following conditions: lung (80 kV, 60 mAs), liver (80 kV/80 mAs and 80 kV/120 mAs), pelvis (100 kV/80 mAs and 100 kV/120 mAs). Depending on gender, the evaluated body region and scan protocol, an effective whole-body dose between 2.9-12.2 mSv, was determined. The radiation exposure administered to gender-specific organs like the female breast tissue (lung perfusion) or to the ovaries (pelvic perfusion) led to an increase in the female specific dose by 86% and 100% in perfusion scans of the lung and the pelvis, respectively. Due to a significant radiation dose of 4D-perfusion-CT protocols, the responsible use of this new promising technique is mandatory. Gender- and organ-specific differences should be considered for indication and planning of tumor perfusion scans

  9. Estimation of Radiation Exposure of 128-Slice 4D-Perfusion CT for the Assessment of Tumor Vascularity

    Science.gov (United States)

    Horger, Marius; Buchgeister, Markus; Fenchel, Michael; Thomas, Christoph; Boehringer, Nadine; Schulze, Maximilian; Tsiflikas, Ilias; Claussen, Claus D.; Heuschmid, Martin

    2010-01-01

    Objective We aimed to estimate the effective dose of 4D-Perfusion-CT protocols of the lung, liver, and pelvis for the assessment of tumor vascularity. Materials and Methods An Alderson-Rando phantom equipped with thermoluminescent dosimeters was used to determine the effective dose values of 4D-Perfusion-CT. Phantom measurements were performed on a 128-slice single-source scanner in adaptive 4D-spiral-mode with bidirectional table movement and a total scan range of 69 mm over a time period of nearly 120 seconds (26 scans). Perfusion measurements were simulated for the lung, liver, and pelvis under the following conditions: lung (80 kV, 60 mAs), liver (80 kV/80 mAs and 80 kV/120 mAs), pelvis (100 kV/80 mAs and 100 kV/120 mAs). Results Depending on gender, the evaluated body region and scan protocol, an effective whole-body dose between 2.9-12.2 mSv, was determined. The radiation exposure administered to gender-specific organs like the female breast tissue (lung perfusion) or to the ovaries (pelvic perfusion) led to an increase in the female specific dose by 86% and 100% in perfusion scans of the lung and the pelvis, respectively. Conclusion Due to a significant radiation dose of 4D-perfusion-CT protocols, the responsible use of this new promising technique is mandatory. Gender- and organ-specific differences should be considered for indication and planning of tumor perfusion scans. PMID:20808699

  10. Estimation of Radiation Exposure of 128-Slice 4D-Perfusion CT for the Assessment of Tumor Vascularity

    Energy Technology Data Exchange (ETDEWEB)

    Ketelsen, Dominik; Horger, Marius; Buchgeister, Markus; Fenchel, Michael; Thomas, Christoph; Boehringer, Nadine; Schulze, Maximilian; Tsiflikas, Ilias; Claussen, Claus D.; Heuschmid, Martin [University Hospital Tuebingen, Tuebingen (Germany)

    2010-10-15

    We aimed to estimate the effective dose of 4D-Perfusion-CT protocols of the lung, liver, and pelvis for the assessment of tumor vascularity. An Alderson-Rando phantom equipped with thermoluminescent dosimeters was used to determine the effective dose values of 4D Perfusion-CT. Phantom measurements were performed on a 128-slice single source scanner in adaptive 4D-spiral-mode with bidirectional table movement and a total scan range of 69 mm over a time period of nearly 120 seconds (26 scans). Perfusion measurements were simulated for the lung, liver, and pelvis under the following conditions: lung (80 kV, 60 mAs), liver (80 kV/80 mAs and 80 kV/120 mAs), pelvis (100 kV/80 mAs and 100 kV/120 mAs). Depending on gender, the evaluated body region and scan protocol, an effective whole-body dose between 2.9-12.2 mSv, was determined. The radiation exposure administered to gender-specific organs like the female breast tissue (lung perfusion) or to the ovaries (pelvic perfusion) led to an increase in the female specific dose by 86% and 100% in perfusion scans of the lung and the pelvis, respectively. Due to a significant radiation dose of 4D-perfusion-CT protocols, the responsible use of this new promising technique is mandatory. Gender- and organ-specific differences should be considered for indication and planning of tumor perfusion scans

  11. Characteristics of Misclassified CT Perfusion Ischemic Core in Patients with Acute Ischemic Stroke.

    Directory of Open Access Journals (Sweden)

    Ralph R E G Geuskens

    Full Text Available CT perfusion (CTP is used to estimate the extent of ischemic core and penumbra in patients with acute ischemic stroke. CTP reliability, however, is limited. This study aims to identify regions misclassified as ischemic core on CTP, using infarct on follow-up noncontrast CT. We aim to assess differences in volumetric and perfusion characteristics in these regions compared to areas that ended up as infarct on follow-up.This study included 35 patients with >100 mm brain coverage CTP. CTP processing was performed using Philips software (IntelliSpace 7.0. Final infarct was automatically segmented on follow-up noncontrast CT and used as reference. CTP and follow-up noncontrast CT image data were registered. This allowed classification of ischemic lesion agreement (core on CTP: rMTT≥145%, aCBV<2.0 ml/100g and infarct on follow-up noncontrast CT and misclassified ischemic core (core on CTP, not identified on follow-up noncontrast CT regions. False discovery ratio (FDR, defined as misclassified ischemic core volume divided by total CTP ischemic core volume, was calculated. Absolute and relative CTP parameters (CBV, CBF, and MTT were calculated for both misclassified CTP ischemic core and ischemic lesion agreement regions and compared using paired rank-sum tests.Median total CTP ischemic core volume was 49.7ml (IQR:29.9ml-132ml; median misclassified ischemic core volume was 30.4ml (IQR:20.9ml-77.0ml. Median FDR between patients was 62% (IQR:49%-80%. Median relative mean transit time was 243% (IQR:198%-289% and 342% (IQR:249%-432% for misclassified and ischemic lesion agreement regions, respectively. Median absolute cerebral blood volume was 1.59 (IQR:1.43-1.79 ml/100g (P<0.01 and 1.38 (IQR:1.15-1.49 ml/100g (P<0.01 for misclassified ischemic core and ischemic lesion agreement, respectively. All CTP parameter values differed significantly.For all patients a considerable region of the CTP ischemic core is misclassified. CTP parameters significantly

  12. Reproducibility of Lobar Perfusion and Ventilation Quantification Using SPECT/CT Segmentation Software in Lung Cancer Patients.

    Science.gov (United States)

    Provost, Karine; Leblond, Antoine; Gauthier-Lemire, Annie; Filion, Édith; Bahig, Houda; Lord, Martin

    2017-09-01

    Planar perfusion scintigraphy with 99m Tc-labeled macroaggregated albumin is often used for pretherapy quantification of regional lung perfusion in lung cancer patients, particularly those with poor respiratory function. However, subdividing lung parenchyma into rectangular regions of interest, as done on planar images, is a poor reflection of true lobar anatomy. New tridimensional methods using SPECT and SPECT/CT have been introduced, including semiautomatic lung segmentation software. The present study evaluated inter- and intraobserver agreement on quantification using SPECT/CT software and compared the results for regional lung contribution obtained with SPECT/CT and planar scintigraphy. Methods: Thirty lung cancer patients underwent ventilation-perfusion scintigraphy with 99m Tc-macroaggregated albumin and 99m Tc-Technegas. The regional lung contribution to perfusion and ventilation was measured on both planar scintigraphy and SPECT/CT using semiautomatic lung segmentation software by 2 observers. Interobserver and intraobserver agreement for the SPECT/CT software was assessed using the intraclass correlation coefficient, Bland-Altman plots, and absolute differences in measurements. Measurements from planar and tridimensional methods were compared using the paired-sample t test and mean absolute differences. Results: Intraclass correlation coefficients were in the excellent range (above 0.9) for both interobserver and intraobserver agreement using the SPECT/CT software. Bland-Altman analyses showed very narrow limits of agreement. Absolute differences were below 2.0% in 96% of both interobserver and intraobserver measurements. There was a statistically significant difference between planar and SPECT/CT methods ( P software is highly reproducible. This tridimensional method yields statistically significant differences in measurements for right lung lobes when compared with planar scintigraphy. We recommend that SPECT/CT-based quantification be used for all lung

  13. Interleaving cerebral CT perfusion with neck CT angiography. Pt. II. Clinical implementation and image quality

    International Nuclear Information System (INIS)

    Oei, Marcel T.H.; Meijer, Frederick J.A.; Woude, Willem-Jan van der; Smit, Ewoud J.; Ginneken, Bram van; Manniesing, Rashindra; Prokop, Mathias

    2017-01-01

    Feasibility evaluation of the One-Step Stroke Protocol, which is an interleaved cerebral computed tomography perfusion (CTP) and neck volumetric computed tomography angiography (vCTA) scanning technique using wide-detector computed tomography, and to assess the image quality of vCTA. Twenty patients with suspicion of acute ischaemic stroke were prospectively scanned and evaluated with a head and neck CTA and with the One-Step Stroke Protocol. Arterial enhancement and contrast-to-noise ratio (CNR) in the carotid arteries was assessed. Three observers scored artefacts and image quality of the cervical arteries. The total z-coverage was evaluated. Mean enhancement in the carotid bifurcation was rated higher in the vCTA (595 ± 164 HU) than CTA (441 ± 117 HU). CNR was rated higher in vCTA. Image quality scores showed no significant difference in the region of the carotid bifurcation between vCTA and CTA. Lower neck image quality scores were slightly lower for vCTA due to artefacts, although not rated as diagnostically relevant. In ten patients, the origin of the left common carotid artery was missed by 1.6 ± 0.8 cm. Mean patient height was 1.8 ± 0.09 m. Carotid bifurcation and origin of vertebral arteries were covered in all patients. The One-Step Stroke Protocol is feasible with good diagnostic image quality of vCTA, although full z-coverage is limited in tall patients. (orig.)

  14. Interleaving cerebral CT perfusion with neck CT angiography. Pt. II. Clinical implementation and image quality

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-06-15

    Feasibility evaluation of the One-Step Stroke Protocol, which is an interleaved cerebral computed tomography perfusion (CTP) and neck volumetric computed tomography angiography (vCTA) scanning technique using wide-detector computed tomography, and to assess the image quality of vCTA. Twenty patients with suspicion of acute ischaemic stroke were prospectively scanned and evaluated with a head and neck CTA and with the One-Step Stroke Protocol. Arterial enhancement and contrast-to-noise ratio (CNR) in the carotid arteries was assessed. Three observers scored artefacts and image quality of the cervical arteries. The total z-coverage was evaluated. Mean enhancement in the carotid bifurcation was rated higher in the vCTA (595 ± 164 HU) than CTA (441 ± 117 HU). CNR was rated higher in vCTA. Image quality scores showed no significant difference in the region of the carotid bifurcation between vCTA and CTA. Lower neck image quality scores were slightly lower for vCTA due to artefacts, although not rated as diagnostically relevant. In ten patients, the origin of the left common carotid artery was missed by 1.6 ± 0.8 cm. Mean patient height was 1.8 ± 0.09 m. Carotid bifurcation and origin of vertebral arteries were covered in all patients. The One-Step Stroke Protocol is feasible with good diagnostic image quality of vCTA, although full z-coverage is limited in tall patients. (orig.)

  15. Characteristics of Misclassified CT Perfusion Ischemic Core in Patients with Acute Ischemic Stroke.

    Science.gov (United States)

    Geuskens, Ralph R E G; Borst, Jordi; Lucas, Marit; Boers, A M Merel; Berkhemer, Olvert A; Roos, Yvo B W E M; van Walderveen, Marianne A A; Jenniskens, Sjoerd F M; van Zwam, Wim H; Dippel, Diederik W J; Majoie, Charles B L M; Marquering, Henk A

    2015-01-01

    CT perfusion (CTP) is used to estimate the extent of ischemic core and penumbra in patients with acute ischemic stroke. CTP reliability, however, is limited. This study aims to identify regions misclassified as ischemic core on CTP, using infarct on follow-up noncontrast CT. We aim to assess differences in volumetric and perfusion characteristics in these regions compared to areas that ended up as infarct on follow-up. This study included 35 patients with >100 mm brain coverage CTP. CTP processing was performed using Philips software (IntelliSpace 7.0). Final infarct was automatically segmented on follow-up noncontrast CT and used as reference. CTP and follow-up noncontrast CT image data were registered. This allowed classification of ischemic lesion agreement (core on CTP: rMTT≥145%, aCBVCT) and misclassified ischemic core (core on CTP, not identified on follow-up noncontrast CT) regions. False discovery ratio (FDR), defined as misclassified ischemic core volume divided by total CTP ischemic core volume, was calculated. Absolute and relative CTP parameters (CBV, CBF, and MTT) were calculated for both misclassified CTP ischemic core and ischemic lesion agreement regions and compared using paired rank-sum tests. Median total CTP ischemic core volume was 49.7ml (IQR:29.9ml-132ml); median misclassified ischemic core volume was 30.4ml (IQR:20.9ml-77.0ml). Median FDR between patients was 62% (IQR:49%-80%). Median relative mean transit time was 243% (IQR:198%-289%) and 342% (IQR:249%-432%) for misclassified and ischemic lesion agreement regions, respectively. Median absolute cerebral blood volume was 1.59 (IQR:1.43-1.79) ml/100g (P<0.01) and 1.38 (IQR:1.15-1.49) ml/100g (P<0.01) for misclassified ischemic core and ischemic lesion agreement, respectively. All CTP parameter values differed significantly. For all patients a considerable region of the CTP ischemic core is misclassified. CTP parameters significantly differed between ischemic lesion agreement and

  16. Admission CT perfusion may overestimate initial infarct core: the ghost infarct core concept.

    Science.gov (United States)

    Boned, Sandra; Padroni, Marina; Rubiera, Marta; Tomasello, Alejandro; Coscojuela, Pilar; Romero, Nicolás; Muchada, Marián; Rodríguez-Luna, David; Flores, Alan; Rodríguez, Noelia; Juega, Jesús; Pagola, Jorge; Alvarez-Sabin, José; Molina, Carlos A; Ribó, Marc

    2017-01-01

    Identifying infarct core on admission is essential to establish the amount of salvageable tissue and indicate reperfusion therapies. Infarct core is established on CT perfusion (CTP) as the severely hypoperfused area, however the correlation between hypoperfusion and infarct core may be time-dependent as it is not a direct indicator of tissue damage. This study aims to characterize those cases in which the admission core lesion on CTP does not reflect an infarct on follow-up imaging. We studied patients with cerebral large vessel occlusion who underwent CTP on admission but received endovascular thrombectomy based on a non-contrast CT Alberta Stroke Program Early CT Score (ASPECTS) >6. Admission infarct core was measured on initial cerebral blood volume (CBV) CTP and final infarct on follow-up CT. We defined ghost infarct core (GIC) as initial core minus final infarct >10 mL. 79 patients were studied. Median National Institutes of Health Stroke Scale (NIHSS) score was 17 (11-20), median time from symptoms to CTP was 215 (87-327) min, and recanalization rate (TICI 2b-3) was 77%. Thirty patients (38%) presented with a GIC >10 mL. GIC >10 mL was associated with recanalization (TICI 2b-3: 90% vs 68%; p=0.026), admission glycemia (185 min: 26%; p=0.033). An adjusted logistic regression model identified time from symptom to CTP imaging 10 mL (OR 2.89, 95% CI 1.04 to 8.09). At 24 hours, clinical improvement was more frequent in patients with GIC >10 mL (66.6% vs 39%; p=0.017). CT perfusion may overestimate final infarct core, especially in the early time window. Selecting patients for reperfusion therapies based on the CTP mismatch concept may deny treatment to patients who might still benefit from reperfusion. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  17. Perfusion CT allows prediction of therapy response in non-small cell lung cancer treated with conventional and anti-angiogenic chemotherapy.

    Science.gov (United States)

    Tacelli, Nunzia; Santangelo, Teresa; Scherpereel, Arnaud; Duhamel, Alain; Deken, Valérie; Klotz, Ernst; Cortot, Alexis; Lafitte, Jean-Jacques; Wallyn, Frédéric; Remy, Jacques; Remy-Jardin, Martine

    2013-08-01

    To determine whether CT can depict early perfusion changes in lung cancer treated by anti-angiogenic drugs, allowing prediction of response. Patients with non-small cell lung cancer, treated by conventional chemotherapy with (Group 1; n = 17) or without (Group 2; n = 23) anti-vascular endothelial growth factor (anti-VEGF) drug (bevacizumab) underwent CT perfusion before (TIME 0) and after 1 (TIME 1), 3 (TIME 2) and 6 (TIME 3) cycles of chemotherapy. The CT parameters evaluated included: (1) total tumour vascular volume (TVV) and total tumour extravascular flow (TEF); (2) RECIST (Response Evaluation Criteria in Solid Tumours) measurements. Tumour response was also assessed on the basis of the clinicians' overall evaluation. In Group 1, significant reduction in perfusion was identified between baseline and: (1) TIME 1 (TVV, P = 0.0395; TEF, P = 0.015); (2) TIME 2 (TVV, P = 0.0043; TEF, P Perfusion CT demonstrates early changes in lung cancer vascularity under anti-angiogenic chemotherapy that may help predict therapeutic response. • Perfusion CT has the potential of providing in vivo information about tumour vasculature. • CT depicts early and specific perfusion changes in NSCLC under anti-angiogenic drugs. • Specific therapeutic effects of anti-angiogenic drugs can be detected before tumour shrinkage. • Early perfusion changes can help predict therapeutic response to anti-angiogenic treatment. • Perfusion CT could be a non-invasive tool to monitor anti-angiogenic treatment.

  18. Comparison of the Peripheral Reactive Hyperemia Index with Myocardial Perfusion Reserve by 82Rb PET/CT in HIV-Infected Patients

    Directory of Open Access Journals (Sweden)

    Mathilde Ørbæk

    2017-05-01

    Full Text Available After the introduction of antiretroviral therapy (ART the life expectancy of patients infected with human immunodeficiency virus (HIV is now approaching that of the general population and the importance of non-AIDS co-morbidities is increasing. Specifically, the risk of coronary artery disease (CAD seems to be higher in HIV-infected patients and an accurate risk prediction of CAD is of high importance for optimal long term treatment. In this study, we assessed the correlation of the endoPAT, which is an office-based CVD screening tool with the myocardial perfusion reserve by 82-rubidium PET/CT. We measured the reactive hyperemia index, which is a measure of the endothelial responsiveness, by the use of an endoPAT device (Itamar Medical, Caesarea, Israel in 48 ART treated HIV-infected patients with high CD 4 cell counts and viral suppression (HIV-RNA < 20 copies/mL, who had previously undergone measurement of the myocardial perfusion reserve by 82-rubidium PET/CT for study purposes. We found an inverse correlation between the reactive hyperemia index and the myocardial perfusion reserve which most likely indicates different vascular physiology. This study did not find evidence to suggest the immediate implementation of the reactive hyperemia index as a screening tool for early coronary artery disease in well-treated HIV-infected patients pending further validation in larger prospective studies.

  19. Endocardial-epicardial distribution of myocardial perfusion reserve assessed by multidetector computed tomography in symptomatic patients without significant coronary artery disease

    DEFF Research Database (Denmark)

    Kühl, Jørgen Tobias; George, Richard T; Mehra, Vishal C

    2016-01-01

    AIM: Previous animal studies have demonstrated differences in perfusion and perfusion reserve between the subendocardium and subepicardium. 320-row computed tomography (CT) with sub-millimetre spatial resolution allows for the assessment of transmural differences in myocardial perfusion reserve...... (MPR) in humans. We aimed to test the hypothesis that MPR in all myocardial layers is determined by age, gender, and cardiovascular risk profile in patients with ischaemic symptoms or equivalent but without obstructive coronary artery disease (CAD). METHODS AND RESULTS: A total of 149 patients enrolled......% [54, 270], P differences...

  20. Brain perfusion CT compared with ¹⁵O-H₂O PET in patients with primary brain tumours

    DEFF Research Database (Denmark)

    Grüner, Julie Marie; Paamand, Rune Tore; Kosteljanetz, Michael

    2012-01-01

    Perfusion CT (PCT) measurements of regional cerebral blood flow (rCBF) have been proposed as a fast and easy method for identifying angiogenically active tumours. In this study, quantitative PCT rCBF measurements in patients with brain tumours were compared to the gold standard PET rCBF with (15)O...

  1. Different CT perfusion algorithms in the detection of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage.

    Science.gov (United States)

    Cremers, Charlotte H P; Dankbaar, Jan Willem; Vergouwen, Mervyn D I; Vos, Pieter C; Bennink, Edwin; Rinkel, Gabriel J E; Velthuis, Birgitta K; van der Schaaf, Irene C

    2015-05-01

    Tracer delay-sensitive perfusion algorithms in CT perfusion (CTP) result in an overestimation of the extent of ischemia in thromboembolic stroke. In diagnosing delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH), delayed arrival of contrast due to vasospasm may also overestimate the extent of ischemia. We investigated the diagnostic accuracy of tracer delay-sensitive and tracer delay-insensitive algorithms for detecting DCI. From a prospectively collected series of aSAH patients admitted between 2007-2011, we included patients with any clinical deterioration other than rebleeding within 21 days after SAH who underwent NCCT/CTP/CTA imaging. Causes of clinical deterioration were categorized into DCI and no DCI. CTP maps were calculated with tracer delay-sensitive and tracer delay-insensitive algorithms and were visually assessed for the presence of perfusion deficits by two independent observers with different levels of experience. The diagnostic value of both algorithms was calculated for both observers. Seventy-one patients were included. For the experienced observer, the positive predictive values (PPVs) were 0.67 for the delay-sensitive and 0.66 for the delay-insensitive algorithm, and the negative predictive values (NPVs) were 0.73 and 0.74. For the less experienced observer, PPVs were 0.60 for both algorithms, and NPVs were 0.66 for the delay-sensitive and 0.63 for the delay-insensitive algorithm. Test characteristics are comparable for tracer delay-sensitive and tracer delay-insensitive algorithms for the visual assessment of CTP in diagnosing DCI. This indicates that both algorithms can be used for this purpose.

  2. A perfusion procedure for imaging of the mouse cerebral vasculature by X-ray micro-CT.

    Science.gov (United States)

    Ghanavati, Sahar; Yu, Lisa X; Lerch, Jason P; Sled, John G

    2014-01-15

    Micro-CT is a novel X-ray imaging modality which can provide 3D high resolution images of the vascular network filled with contrast agent. The cerebrovascular system is a complex anatomical structure that can be imaged with contrast enhanced micro-CT. However, the morphology of the cerebrovasculature and many circulatory anastomosis in the brain result in high variations in the extent of contrast agent filling in the blood vessels and as a result, the vasculature of different subjects appear differently in the acquired images. Specifically, the posterior circulation is not consistently perfused with the contrast agent in many brain specimens and thus, many major vessels that perfuse blood to the midbrain and hindbrain are not visible in the micro-CT images acquired from these samples. In this paper, we present a modified surgical procedure of cerebral vasculature perfusion through the left ventricle with Microfil contrast agent, in order to achieve a more uniform perfusion of blood vessels throughout the brain and as a result, more consistent images of the cerebrovasculature. Our method consists of filling the posterior cerebral circulation with contrast agent, followed by the perfusion of the whole cerebrovasculature. Our histological results show that over 90% of the vessels in the entire brain, including the cerebellum, were filled with contrast agent. Our results show that the new technique of sample perfusion decreases the variability of the posterior circulation in the cerebellum in micro-CT images by 6.9%. This new technique of sample preparation improves the quality of cerebrovascular images. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Metastases to the Liver from Neuroendocrine Tumors: Effect of Duration of Scan Acquisition on CT Perfusion Values

    Science.gov (United States)

    Hobbs, Brian P.; Chandler, Adam G.; Anderson, Ella F.; Herron, Delise H.; Charnsangavej, Chusilp; Yao, James

    2013-01-01

    Purpose To assess the effects of acquisition duration on computed tomographic (CT) perfusion parameter values in neuroendocrine liver metastases and normal liver tissue. Materials and Methods This retrospective study was institutional review board approved, with waiver of informed consent. CT perfusion studies in 16 patients (median age, 57.5 years; range, 42.0–69.7 years), including six men (median, 54.1 years; range, 42.0–69.7), and 10 women (median, 59.3 years; range 43.6–66.3), with neuroendocrine liver metastases were analyzed by means of distributed parametric modeling to determine tissue blood flow, blood volume, mean transit time, permeability, and hepatic arterial fraction for tumors and normal liver tissue. Analyses were undertaken with acquisition time of 12–590 seconds. Nonparameteric regression analyses were used to evaluate the functional relationships between CT perfusion parameters and acquisition duration. Evidence for time invariance was evaluated for each parameter at multiple time points by inferring the fitted derivative to assess its proximity to zero as a function of acquisition time by using equivalence tests with three levels of confidence (20%, 70%, and 90%). Results CT perfusion parameter values varied, approaching stable values with increasing acquisition duration. Acquisition duration greater than 160 seconds was required to obtain at least low confidence stability in any of the CT perfusion parameters. At 160 seconds of acquisition, all five CT perfusion parameters stabilized with low confidence in tumor and normal tissues, with the exception of hepatic arterial fraction in tumors. After 220 seconds of acquisition, there was stabilization with moderate confidence for blood flow, blood volume, and hepatic arterial fraction in tumors and normal tissue, and for mean transit time in tumors; however, permeability values did not satisfy the moderate stabilization criteria in both tumors and normal tissue until 360 seconds of

  4. Radiation dose reduction in cerebral CT perfusion imaging using iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Niesten, Joris M.; Schaaf, Irene C. van der; Riordan, Alan J.; Jong, Hugo W.A.M. de; Eijspaart, Daniel; Smit, Ewoud J.; Mali, Willem P.T.M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Horsch, Alexander D. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Rijnstate Hospital, Department of Radiology, Arnhem (Netherlands)

    2014-02-15

    To investigate whether iterative reconstruction (IR) in cerebral CT perfusion (CTP) allows for 50 % dose reduction while maintaining image quality (IQ). A total of 48 CTP examinations were reconstructed into a standard dose (150 mAs) with filtered back projection (FBP) and half-dose (75 mAs) with two strengths of IR (middle and high). Objective IQ (quantitative perfusion values, contrast-to-noise ratio (CNR), penumbra, infarct area and penumbra/infarct (P/I) index) and subjective IQ (diagnostic IQ on a four-point Likert scale and overall IQ binomial) were compared among the reconstructions. Half-dose CTP with high IR level had, compared with standard dose with FBP, similar objective (grey matter cerebral blood volume (CBV) 4.4 versus 4.3 mL/100 g, CNR 1.59 versus 1.64 and P/I index 0.74 versus 0.73, respectively) and subjective diagnostic IQ (mean Likert scale 1.42 versus 1.49, respectively). The overall IQ in half-dose with high IR level was scored lower in 26-31 %. Half-dose with FBP and with the middle IR level were inferior to standard dose with FBP. With the use of IR in CTP imaging it is possible to examine patients with a half dose without significantly altering the objective and diagnostic IQ. The standard dose with FBP is still preferable in terms of subjective overall IQ in about one quarter of patients. (orig.)

  5. Accuracy of the detection of infratentorial stroke lesions using perfusion CT: an experimenter-blinded study

    International Nuclear Information System (INIS)

    Lee, In Hyouk; Kim, Myung Soon; Kim, Young Ju; Lee, Myeong Sub; You, Joshua H.; Lee, Ji Yong; Whang, Kum

    2010-01-01

    Although perfusion CT (PCT) for the detection of supratentorial stroke is well established, there is a dearth of evidence of its effectiveness in the detection of infratentorial stroke. Hence, this study compared sensitivity, specificity, and accuracy of PCT maps between infratentorial and supratentorial stroke lesions. One hundred patients with acute stroke who had successfully undergone near whole-brain PCT with the toggling table technique and follow-up MRI were included. Wilcoxon Mann-Whitney test was performed at P 0.01 in all PCT maps) between supratentorial and infratentorial stroke. Also, there was no remarkable difference in both sensitivity and specificity of PCT maps. This was the first study to investigate the accuracy of PCT with the toggling table technique in detection of infratentorial stroke lesions. Clinically, PCT is highly reliable and accurate in detecting infratentorial stroke lesions. (orig.)

  6. CT enteroclysis in small bowel Crohn's disease

    International Nuclear Information System (INIS)

    Kohli, Marc D.; Maglinte, Dean D.T.

    2009-01-01

    The diagnostic evaluation of small bowel Crohn's disease has changed dramatically over the last decade. The introduction of wireless capsule endoscopy, double balloon endoscopy and the introduction of newer therapeutic agents have changed the role of imaging in the small bowel. Additionally, advances in multidetector CT technology have further changed how radiologic investigations are utilized in the diagnosis and management of small bowel Crohn's disease. This article describes how we perform CT enteroclysis in the investigation of small bowel Crohn's disease and discusses the role of CT enteroclysis in the current management of small bowel Crohn's disease.

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

    Science.gov (United States)

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

    2014-04-07

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

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

    Science.gov (United States)

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

    2014-04-01

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

  9. CT perfusion imaging as an early biomarker of differential response to stereotactic radiosurgery in C6 rat gliomas.

    Directory of Open Access Journals (Sweden)

    Timothy Pok Chi Yeung

    Full Text Available The therapeutic efficacy of stereotactic radiosurgery for glioblastoma is not well understood, and there needs to be an effective biomarker to identify patients who might benefit from this treatment. This study investigated the efficacy of computed tomography (CT perfusion imaging as an early imaging biomarker of response to stereotactic radiosurgery in a malignant rat glioma model.Rats with orthotopic C6 glioma tumors received either mock irradiation (controls, N = 8 or stereotactic radiosurgery (N = 25, 12 Gy in one fraction delivered by Helical Tomotherapy. Twelve irradiated animals were sacrificed four days after stereotactic radiosurgery to assess acute CT perfusion and histological changes, and 13 irradiated animals were used to study survival. Irradiated animals with survival >15 days were designated as responders while those with survival ≤15 days were non-responders. Longitudinal CT perfusion imaging was performed at baseline and regularly for eight weeks post-baseline.Early signs of radiation-induced injury were observed on histology. There was an overall survival benefit following stereotactic radiosurgery when compared to the controls (log-rank P<0.04. Responders to stereotactic radiosurgery showed lower relative blood volume (rBV, and permeability-surface area (PS product on day 7 post-stereotactic radiosurgery when compared to controls and non-responders (P<0.05. rBV and PS on day 7 showed correlations with overall survival (P<0.05, and were predictive of survival with 92% accuracy.Response to stereotactic radiosurgery was heterogeneous, and early selection of responders and non-responders was possible using CT perfusion imaging. Validation of CT perfusion indices for response assessment is necessary before clinical implementation.

  10. Whole brain CT perfusion in acute anterior circulation ischemia: coverage size matters

    Energy Technology Data Exchange (ETDEWEB)

    Emmer, B.J. [Erasmus Medical Centre, Department of Radiology, Postbus 2040, Rotterdam (Netherlands); Rijkee, M.; Walderveen, M.A.A. van [Leiden University Medical Centre, Department of Radiology, Leiden (Netherlands); Niesten, J.M.; Velthuis, B.K. [University Medical Centre Utrecht, Department of Radiology, Utrecht (Netherlands); Wermer, M.J.H. [Leiden University Medical Centre, Department of Neurology, Leiden (Netherlands)

    2014-12-15

    Our aim was to compare infarct core volume on whole brain CT perfusion (CTP) with several limited coverage sizes (i.e., 3, 4, 6, and 8 cm), as currently used in routine clinical practice. In total, 40 acute ischemic stroke patients with non-contrast CT (NCCT) and CTP imaging of anterior circulation ischemia were included. Imaging was performed using a 320-multislice CT. Average volumes of infarct core of all simulated partial coverage sizes were calculated. Infarct core volume of each partial brain coverage was compared with infarct core volume of whole brain coverage and expressed using a percentage. To determine the optimal starting position for each simulated CTP coverage, the percentage of infarct coverage was calculated for every possible starting position of the simulated partial coverage in relation to Alberta Stroke Program Early CT Score in Acute Stroke Triage (ASPECTS 1) level. Whole brain CTP coverage further increased the percentage of infarct core volume depicted by 10 % as compared to the 8-cm coverage when the bottom slice was positioned at the ASPECTS 1 level. Optimization of the position of the region of interest (ROI) in 3 cm, 4 cm, and 8 cm improved the percentage of infarct depicted by 4 % for the 8-cm, 7 % for the 4-cm, and 13 % for the 3-cm coverage size. This study shows that whole brain CTP is the optimal coverage for CTP with a substantial improvement in accuracy in quantifying infarct core size. In addition, our results suggest that the optimal position of the ROI in limited coverage depends on the size of the coverage. (orig.)

  11. Reliability of CT perfusion in the evaluation of the ischaemic penumbra.

    Science.gov (United States)

    Alves, José Eduardo; Carneiro, Ângelo; Xavier, João

    2014-02-01

    CT perfusion (CTP) is part of the initial evaluation of stroke patients, allowing differentiation between infarcted tissue and the ischaemic penumbra and helping in the selection of patients for endovascular treatment. This study assessed the reliability of the qualitative evaluation CTP maps in defining the ischemic penumbra and identified potential pitfalls associated with this technique. We reviewed CTP scans of 45 consecutive patients admitted to our institution with anterior circulation acute ischaemic stroke. Two neuroradiologists performed qualitative evaluations of cerebral blood volume (CBV) and mean transit time (MTT) maps, using 24h follow-up non-contrast CT as surrogate marker for the area of definitive infarct. For each slice analyzed, the area of qualitative alteration in the CBV and MTT maps was classified as either being inferior, equal or superior to the area of infarct on the follow-up CT. Three out of 45 (7%) patients had admission CT CBV abnormalities larger than follow-up lesions; 34/45 (76%) patients had infarct areas smaller than initial MTT prolongation. In the group of patients with no recanalization 12/19 (63%) had infarct areas smaller than initial MTT lesion. CBV abnormality is a reliable marker for an irreversible ischaemic lesion, although rarely it may overestimate the ischaemic "core", possibly due to delay in contrast arrival to the brain. In the majority of patients without recanalization, MTT overestimated final infarct areas, probably because it does not differentiate true "at risk" penumbra from benign oligaemia. Qualitative evaluation of CBV and MTT maps may overestimate the real ischaemic penumbra.

  12. TU-EF-204-02: Hiigh Quality and Sub-MSv Cerebral CT Perfusion Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ke; Niu, Kai; Wu, Yijing; Chen, Guang-Hong [University of Wisconsin, Madison, WI (United States)

    2015-06-15

    Purpose: CT Perfusion (CTP) imaging is of great importance in acute ischemic stroke management due to its potential to detect hypoperfused yet salvageable tissue and distinguish it from definitely unsalvageable tissue. However, current CTP imaging suffers from poor image quality and high radiation dose (up to 5 mSv). The purpose of this work was to demonstrate that technical innovations such as Prior Image Constrained Compressed Sensing (PICCS) have the potential to address these challenges and achieve high quality and sub-mSv CTP imaging. Methods: (1) A spatial-temporal 4D cascaded system model was developed to indentify the bottlenecks in the current CTP technology; (2) A task-based framework was developed to optimize the CTP system parameters; (3) Guided by (1) and (2), PICCS was customized for the reconstruction of CTP source images. Digital anthropomorphic perfusion phantoms, animal studies, and preliminary human subject studies were used to validate and evaluate the potentials of using these innovations to advance the CTP technology. Results: The 4D cascaded model was validated in both phantom and canine stroke models. Based upon this cascaded model, it has been discovered that, as long as the spatial resolution and noise properties of the 4D source CT images are given, the 3D MTF and NPS of the final CTP maps can be analytically derived for a given set of processing methods and parameters. The cascaded model analysis also identified that the most critical technical factor in CTP is how to acquire and reconstruct high quality source images; it has very little to do with the denoising techniques often used after parametric perfusion calculations. This explained why PICCS resulted in a five-fold dose reduction or substantial improvement in image quality. Conclusion: Technical innovations generated promising results towards achieving high quality and sub-mSv CTP imaging for reliable and safe assessment of acute ischemic strokes. K. Li, K. Niu, Y. Wu: Nothing to

  13. TU-EF-204-02: Hiigh Quality and Sub-MSv Cerebral CT Perfusion Imaging

    International Nuclear Information System (INIS)

    Li, Ke; Niu, Kai; Wu, Yijing; Chen, Guang-Hong

    2015-01-01

    Purpose: CT Perfusion (CTP) imaging is of great importance in acute ischemic stroke management due to its potential to detect hypoperfused yet salvageable tissue and distinguish it from definitely unsalvageable tissue. However, current CTP imaging suffers from poor image quality and high radiation dose (up to 5 mSv). The purpose of this work was to demonstrate that technical innovations such as Prior Image Constrained Compressed Sensing (PICCS) have the potential to address these challenges and achieve high quality and sub-mSv CTP imaging. Methods: (1) A spatial-temporal 4D cascaded system model was developed to indentify the bottlenecks in the current CTP technology; (2) A task-based framework was developed to optimize the CTP system parameters; (3) Guided by (1) and (2), PICCS was customized for the reconstruction of CTP source images. Digital anthropomorphic perfusion phantoms, animal studies, and preliminary human subject studies were used to validate and evaluate the potentials of using these innovations to advance the CTP technology. Results: The 4D cascaded model was validated in both phantom and canine stroke models. Based upon this cascaded model, it has been discovered that, as long as the spatial resolution and noise properties of the 4D source CT images are given, the 3D MTF and NPS of the final CTP maps can be analytically derived for a given set of processing methods and parameters. The cascaded model analysis also identified that the most critical technical factor in CTP is how to acquire and reconstruct high quality source images; it has very little to do with the denoising techniques often used after parametric perfusion calculations. This explained why PICCS resulted in a five-fold dose reduction or substantial improvement in image quality. Conclusion: Technical innovations generated promising results towards achieving high quality and sub-mSv CTP imaging for reliable and safe assessment of acute ischemic strokes. K. Li, K. Niu, Y. Wu: Nothing to

  14. Multiparametric PET/CT-perfusion does not add significant additional information for initial staging in lung cancer compared with standard PET/CT

    Science.gov (United States)

    2014-01-01

    Background The purpose of this study was to assess the relationship of CT-perfusion (CTP), 18F-FDG-PET/CT and histological parameters, and the possible added value of CTP to FDG-PET/CT in the initial staging of lung cancer. Methods Fifty-four consecutive patients (median age 65 years, 15 females, 39 males) with suspected lung cancer were evaluated prospectively by CT-perfusion scan and 18F-FDG-PET/CT scan. Overall, 46 tumors were identified. CTP parameters blood flow (BF), blood volume (BV), and mean transit time (MTT) of the tumor tissue were calculated. Intratumoral microvessel density (MVD) was assessed quantitatively. Differences in CTP parameters concerning tumor type, location, PET positivity of lymph nodes, TNM status, and UICC stage were analyzed. Spearman correlation analyses between CTP and 18F-FDG-PET/CT parameters (SUVmax, SUVmean, PETvol, and TLG), MVD, tumor size, and tumor stage were performed. Results The mean BF (mL/100 mL min-1), BV (mL/100 mL), and MTT (s) was 35.5, 8.4, and 14.2, respectively. The BF and BV were lower in tumors with PET-positive lymph nodes (p = 0.02). However, the CTP values were not significantly different among the N stages. The CTP values were not different, depending on tumor size and location. No significant correlation was found between CTP parameters and MVD. Conclusions Overall, the CTP information showed only little additional information for the initial staging compared with standard FDG-PET/CT. Low perfusion in lung tumors might possibly be associated with metabolically active regional lymph nodes. Apart from that, both CTP and 18F-FDG-PET/CT parameter sets may reflect different pathophysiological mechanisms in lung cancer. PMID:24450990

  15. An efficient polyenergetic SART (pSART) reconstruction algorithm for quantitative myocardial CT perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yuan, E-mail: yuan.lin@duke.edu; Samei, Ehsan [Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, 2424 Erwin Road, Suite 302, Durham, North Carolina 27705 (United States)

    2014-02-15

    Purpose: In quantitative myocardial CT perfusion imaging, beam hardening effect due to dense bone and high concentration iodinated contrast agent can result in visible artifacts and inaccurate CT numbers. In this paper, an efficient polyenergetic Simultaneous Algebraic Reconstruction Technique (pSART) was presented to eliminate the beam hardening artifacts and to improve the CT quantitative imaging ability. Methods: Our algorithm made threea priori assumptions: (1) the human body is composed of several base materials (e.g., fat, breast, soft tissue, bone, and iodine); (2) images can be coarsely segmented to two types of regions, i.e., nonbone regions and noniodine regions; and (3) each voxel can be decomposed into a mixture of two most suitable base materials according to its attenuation value and its corresponding region type information. Based on the above assumptions, energy-independent accumulated effective lengths of all base materials can be fast computed in the forward ray-tracing process and be used repeatedly to obtain accurate polyenergetic projections, with which a SART-based equation can correctly update each voxel in the backward projecting process to iteratively reconstruct artifact-free images. This approach effectively reduces the influence of polyenergetic x-ray sources and it further enables monoenergetic images to be reconstructed at any arbitrarily preselected target energies. A series of simulation tests were performed on a size-variable cylindrical phantom and a realistic anthropomorphic thorax phantom. In addition, a phantom experiment was also performed on a clinical CT scanner to further quantitatively validate the proposed algorithm. Results: The simulations with the cylindrical phantom and the anthropomorphic thorax phantom showed that the proposed algorithm completely eliminated beam hardening artifacts and enabled quantitative imaging across different materials, phantom sizes, and spectra, as the absolute relative errors were reduced

  16. Improvement of myocardial perfusion detected by 201Tl scintigraphy on cardiac rehabilitation for patients with coronary artery disease

    International Nuclear Information System (INIS)

    Li, Linxue; Nohara, Ryuji; Makita, Shigeru

    1996-01-01

    The effect of cardiac rehabilitation (mean 70±48 months) on myocardial perfusion was assessed using thallium-201 ( 201 Tl) exercise study in 63 patients with coronary artery disease (CAD). Subjects were those in a rehabilitation group (Rh=42) participating in supervised sports training two to three times per week and the control group (Ct=21) not taking active daily exercise. The interval between two 201 Tl SPECT studies was 19±16 months. After physical training, total duration of the exercise test increased from 443±112 to 536±121 seconds (+19%) in the Rh group, and from 484±129 to 432±115 seconds in the Ct group (-10.7%) (p 2 to 269.8±58 x 10 2 in the Rh group and decreased from 218.7±40 x 10 2 to 216.6±76 x 10 2 (p 201 Tl myocardial perfusion defect on exercise improved more in 54.8% (stress 59.5%, rest 35.7%) in the Rh group than in the Ct group (9.5%, p 201 Tl perfusion defect decreased from 68 (23.1%) to 49 regions (16.7%) of 294 total myocardial regions in the Rh group on exercise. However. it increased from 39 (26.5%) to 44 (29.9%) regions of 147 regions in the Ct group (p<0.01). Thus, cardiac rehabilitation increases exercise tolerance with improvement of myocardial perfusion. suggesting that cardiac rehabilitation is an advisable and effective treatment for patients with ischemic heart disease. (author)

  17. Spatial correspondence of 4D CT ventilation and SPECT pulmonary perfusion defects in patients with malignant airway stenosis

    Science.gov (United States)

    Castillo, Richard; Castillo, Edward; McCurdy, Matthew; Gomez, Daniel R.; Block, Alec M.; Bergsma, Derek; Joy, Sarah; Guerrero, Thomas

    2012-04-01

    To determine the spatial overlap agreement between four-dimensional computed tomography (4D CT) ventilation and single photon emission computed tomography (SPECT) perfusion hypo-functioning pulmonary defect regions in a patient population with malignant airway stenosis. Treatment planning 4D CT images were obtained retrospectively for ten lung cancer patients with radiographically demonstrated airway obstruction due to gross tumor volume. Each patient also received a SPECT perfusion study within one week of the planning 4D CT, and prior to the initiation of treatment. Deformable image registration was used to map corresponding lung tissue elements between the extreme component phase images, from which quantitative three-dimensional (3D) images representing the local pulmonary specific ventilation were constructed. Semi-automated segmentation of the percentile perfusion distribution was performed to identify regional defects distal to the known obstructing lesion. Semi-automated segmentation was similarly performed by multiple observers to delineate corresponding defect regions depicted on 4D CT ventilation. Normalized Dice similarity coefficient (NDSC) indices were determined for each observer between SPECT perfusion and 4D CT ventilation defect regions to assess spatial overlap agreement. Tidal volumes determined from 4D CT ventilation were evaluated versus measurements obtained from lung parenchyma segmentation. Linear regression resulted in a linear fit with slope = 1.01 (R2 = 0.99). Respective values for the average DSC, NDSC1 mm and NDSC2 mm for all cases and multiple observers were 0.78, 0.88 and 0.99, indicating that, on average, spatial overlap agreement between ventilation and perfusion defect regions was comparable to the threshold for agreement within 1-2 mm uncertainty. Corresponding coefficients of variation for all metrics were similarly in the range: 0.10%-19%. This study is the first to quantitatively assess 3D spatial overlap agreement between

  18. Optimisation of reconstruction for the registration of CT liver perfusion sequences

    Science.gov (United States)

    Romain, B.; Letort, V.; Lucidarme, O.; d'Alché-Buc, F.; Rouet, L.

    2012-02-01

    Objective. CT abdominal perfusion is frequently used to evaluate tumor evolution when patients are undergoing antiangiogenic therapy. Parameters depending on longer-term dynamics of the diffusion of the contrast medium (e. g. permeability) could help assessing the treatment efficacy. To this end, dynamic image sequences are obtained while patients breath freely. Prior to any analysis, one needs to compensate the respiratory motion. The goal of our study is to optimize the CT reconstruction parameters (filter of reconstruction, thickness of image volumes) for our registration method. We also aim at proposing relevant criteria allowing to quantify the registration quality. Methods. Registration is computed in 4 steps: z-global rigid registration, local refinements with multiresolution blockmatching, regularization and warping. Two new criteria are defined to evaluate the quality of registration: one for spatial evaluation and the other for temporal evaluation. Results. The two measures decrease after registration (58% and 10% average decrease for the best reconstruction parameters for the spatial and temporal criteria respectively) which is consistent with visual inspection of the images. They are therefore used to determine the best combination of reconstruction parameters.

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

    Science.gov (United States)

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

    2016-03-01

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

  20. EANM procedural guidelines for radionuclide myocardial perfusion imaging with SPECT and SPECT/CT: 2015 revision

    Energy Technology Data Exchange (ETDEWEB)

    Verberne, Hein J.; Eck-Smit, Berthe L.F. van; Wit, Tim C. de [University of Amsterdam, Department of Nuclear Medicine, F2-238, Academic Medical Center, Amsterdam (Netherlands); Acampa, Wanda [National Council of Research, Institute of Biostructures and Bioimaging, Naples (Italy); Anagnostopoulos, Constantinos [Academy of Athens, Center for Experimental Surgery, Clinical and Translational Research, Biomedical Research Foundation, Athens (Greece); Ballinger, Jim [Guy' s Hospital - Guy' s and St Thomas' Trust Foundation, Department of Nuclear Medicine, London (United Kingdom); Bengel, Frank [Hannover Medical School, Department of Nuclear Medicine, Hannover (Germany); Bondt, Pieter De [OLV Hospital, Department of Nuclear Medicine, Aalst (Belgium); Buechel, Ronny R.; Kaufmann, Philip A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Cuocolo, Alberto [University Federico II, Department of Advanced Biomedical Sciences, Naples (Italy); Flotats, Albert [Universitat Autonoma de Barcelona, Nuclear Medicine Department, Hospital de la Santa Creu i Sant Pau, Barcelona (Spain); Hacker, Marcus [Medical University of Vienna, Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Vienna (Austria); Hindorf, Cecilia [Skaane University Hospital, Department of Radiation Physics, Lund (Sweden); Lindner, Oliver [University Hospital of the Ruhr-University Bochum, Heart and Diabetes Center North Rhine-Westphalia, Institute for Radiology, Nuclear Medicine and Molecular Imaging, Bad Oeynhausen (Germany); Ljungberg, Michael [Lund University, Department of Medical Radiation Physics, Lund (Sweden); Lonsdale, Markus [Bispebjerg Hospital, Department of Clinical Physiology and Nuclear Medicine, Copenhagen (Denmark); Manrique, Alain [Caen University Hospital, Department of Nuclear Medicine, Service Commun Investigations chez l' Homme, GIP Cyceron, Caen (France); Minarik, David [Skaane University Hospital, Radiation Physics, Malmoe (Sweden); Scholte, Arthur J.H.A. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); Slart, Riemer H.J.A. [University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); Traegaardh, Elin [Skaane University Hospital and Lund University, Clinical Physiology and Nuclear Medicine, Malmoe (Sweden); Hesse, Birger [University Hospital of Copenhagen, Department of Clinical Physiology and Nuclear Medicine and PET, Rigshospitalet, Copenhagen (Denmark)

    2015-11-15

    Since the publication of the European Association of Nuclear Medicine (EANM) procedural guidelines for radionuclide myocardial perfusion imaging (MPI) in 2005, many small and some larger steps of progress have been made, improving MPI procedures. In this paper, the major changes from the updated 2015 procedural guidelines are highlighted, focusing on the important changes related to new instrumentation with improved image information and the possibility to reduce radiation exposure, which is further discussed in relation to the recent developments of new International Commission on Radiological Protection (ICRP) models. Introduction of the selective coronary vasodilator regadenoson and the use of coronary CT-contrast agents for hybrid imaging with SPECT/CT angiography are other important areas for nuclear cardiology that were not included in the previous guidelines. A large number of minor changes have been described in more detail in the fully revised version available at the EANM home page: http://eanm.org/ publications/guidelines/2015{sub 0}7{sub E}ANM{sub F}INAL myocardial{sub p}erfusion{sub g}uideline.pdf. (orig.)

  1. Iodine concentration as a perfusion surrogate marker in oncology: Further elucidation of the underlying mechanisms using Volume Perfusion CT with 80 kVp.

    Science.gov (United States)

    Thaiss, Wolfgang M; Haberland, Ulrike; Kaufmann, Sascha; Spira, Daniel; Thomas, Christoph; Nikolaou, Konstantin; Horger, Marius; Sauter, Alexander W

    2016-09-01

    To assess the value of iodine concentration (IC) in computed tomography data acquired with 80 kVp, as a surrogate for perfusion imaging in hepatocellular carcinoma (HCC) and lymphoma by comparing iodine related attenuation (IRA) with quantitative Volume Perfusion CT (VPCT)-parameters. VPCT-parameters were compared with intra-tumoral IC at 5 time points after the aortic peak enhancement (APE) with a temporal resolution of 3.5 sec in untreated 30 HCC and 30 lymphoma patients. Intra-tumoral perfusion parameters for HCC showed a blood flow (BF) of 52.7 ± 17.0 mL/100 mL/min, blood volume (BV) 12.6 ± 4.3 mL/100 mL, arterial liver perfusion (ALP) 44.4 ± 12.8 mL/100 mL/min. Lesion IC 7 sec after APE was 133.4 ± 57.3 mg/100 mL. Lymphoma showed a BF of 36.8 ± 13.4 mL/100 mL/min, BV of 8.8 ± 2.8 mL/100 mL and IC of 118.2 ± 64.5 mg/100 mL 3.5 sec after APE. Strongest correlations exist for VPCT-derived BF and ALP with IC in HCC 7 sec after APE (r = 0.71 and r = 0.84) and 3.5 sec after APE in lymphoma lesions (r = 0.77). Significant correlations are also present for BV (r = 0.60 and r = 0.65 for HCC and lymphoma, respectively). We identified a good, time-dependent agreement between VPCT-derived flow values and IC in HCC and lymphoma. Thus, CT-derived ICs 7 sec after APE in HCC and 3.5 sec in lymphoma may be used as surrogate imaging biomarkers for tumor perfusion with 80 kVp. • Iodine concentration derived from low kVp CT is regarded as perfusion surrogate • Correlation with Perfusion CT was performed to elucidate timing and histology dependencies • Highest correlation was present 7 sec after aortic peak enhancement in hepatocellular carcinoma • In lymphoma, highest correlation was calculated 3.5 sec after aortic peak enhancement • With these results, further optimization of Dual energy CT protocols is possible.

  2. Optimal timing of image acquisition for arterial first pass CT myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pelgrim, G.J., E-mail: g.j.pelgrim@umcg.nl [University of Groningen, University Medical Center Groningen, Center for Medical Imaging North East Netherlands (CMI-nen), Hanzeplein 1, 9713 GZ Groningen (Netherlands); Nieuwenhuis, E.R., E-mail: e.r.nieuwenhuis@student.utwente.nl [University of Groningen, University Medical Center Groningen, Center for Medical Imaging North East Netherlands (CMI-nen), Hanzeplein 1, 9713 GZ Groningen (Netherlands); University of Twente, P.O. Box 217, 7500 AE, Enschede (Netherlands); Duguay, T.M., E-mail: duguay@musc.edu [Medical University of South Carolina, Dept. of Radiology, 25 Courtenay Drive, SC 29425, Charleston (United States); Geest, R.J. van der, E-mail: R.J.van_der_Geest@lumc.nl [Leiden University Medical Center, Dept. of Radiology, Postbus 9600, 2300 RC, Leiden (Netherlands); Varga-Szemes, A., E-mail: vargaasz@musc.edu [Medical University of South Carolina, Dept. of Radiology, 25 Courtenay Drive, SC 29425, Charleston (United States); Slump, C.H., E-mail: c.h.slump@utwente.nl [University of Groningen, University Medical Center Groningen, Center for Medical Imaging North East Netherlands (CMI-nen), Hanzeplein 1, 9713 GZ Groningen (Netherlands); University of Twente, P.O. Box 217, 7500 AE, Enschede (Netherlands); Fuller, S.R., E-mail: fullerst@musc.edu [Medical University of South Carolina, Dept. of Radiology, 25 Courtenay Drive, SC 29425, Charleston (United States); Oudkerk, M., E-mail: m.oudkerk@umcg.nl [University of Groningen, University Medical Center Groningen, Center for Medical Imaging North East Netherlands (CMI-nen), Hanzeplein 1, 9713 GZ Groningen (Netherlands); Schoepf, U.J., E-mail: schoepf@musc.edu [Medical University of South Carolina, Dept. of Radiology, 25 Courtenay Drive, SC 29425, Charleston (United States); and others

    2017-01-15

    Highlights: • Optimal timing of static, single-shot CT perfusion scans is important to differentiate ischemic from non-ischemic myocardial segments. • Time delay between reaching 150 and 250 HU thresholds in the ascending aorta and optimal contrast in the myocardium are 4 and 2 s, respectively. • Attenuation difference of more than 15 HU between normal and ischemic myocardium is present during approximately 8 s. - Abstract: Purpose: To determine the optimal timing of arterial first pass computed tomography (CT) myocardial perfusion imaging (CTMPI) based on dynamic CTMPI acquisitions. Methods and materials: Twenty-five patients (59 ± 8.4 years, 14 male)underwent adenosine-stress dynamic CTMPI on second-generation dual-source CT in shuttle mode (30 s at 100 kV and 300 mAs). Stress perfusion magnetic resonance imaging (MRI) was used as reference standard for differentiation of non-ischemic and ischemic segments. The left ventricle (LV) wall was manually segmented according to the AHA 16-segment model. Hounsfield units (HU) in myocardial segments and ascending (AA) and descending aorta (AD) were monitored over time. Time difference between peak AA and peak AD and peak myocardial enhancement was calculated, as well as the, time delay from fixed HU thresholds of 150 and 250 HU in the AA and AD to a minimal difference of 15 HU between normal and ischemic segments. Furthermore, the duration of the 15 HU difference between ischemic and non-ischemic segments was calculated. Results: Myocardial ischemia was observed by MRI in 10 patients (56.3 ± 9.0 years; 8 male). The delay between the maximum HU in the AA and AD and maximal HU in the non-ischemic segments was 2.8 s [2.2–4.3] and 0.0 s [0.0–2.8], respectively. Differentiation between ischemic and non-ischemic myocardial segments in CT was best during a time window of 8.6 ± 3.8 s. Time delays for AA triggering were 4.5 s [2.2–5.6] and 2.2 s [0–2.8] for the 150 HU and 250 HU thresholds, respectively. While for

  3. Detection of extracardiac disease during Tl-201 myocardial perfusion study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan H.; Lee, Myoung Hoon; Yoon, Seok Nam; Hwang, Kyung Hoon [College of Medicine, Ajou Univ., Suwon (Korea, Republic of)

    2001-07-01

    It is important to observe extracardiac disease processes (ECD) during cardiac perfusion imaging for valuable information can be obtained at no extracost to patients. The aim of the study is to find out the frequency of ECD during Tl-201 stress myocardial perfusion imaging (TSMPI). Retrospective evaluation of 552 TSMPI was done. There were 229 males and 223 females reffered for evaluation of possible ischemic heart disease. Their ages range from 20 to 80 with mean age of 58.8 years. Three mCi (111 MBq) of 201 TlCl is used for adenosine or treadmil exercise testing and myocardial SPECT is performed utilizing low energy high resolution collimators and a triple-head camera ( MultiSPECT, Siemens medical systems, Inc., Hoffman Estate, III., USA). In addition to routine cardiac Tl-201 SPECT acquisition, included in the protocol is 1 min, anterior planar views in 128 128 matrix after stress and rest SPECT studies for evaluation of lung uptake and chamber size. Utilizing these views ECD is assessed. Five patients had focal increased activity suggesting tumor and 3 of 5 cases were confirmed as malignancy. The malignancies were thyroid cancer (Hurthle cell), lung cancer, and breast cancer. Benign lesions were autonomous thyroid nodule and pheochromocytoma. Other ECDs include pericardial effusion, pleural effusion, and paralyzed hemidiapharm.. Extracardiac disease processes such as benign or malignancy are easily detected during Tl-201 myocardial perfusion imaging using our acquisition protocol at no cost to the patients. This information could be life saving in some patients for early detection of clinically unsuspected malignancy.

  4. Clinical application of lower extremity CTA and lower extremity perfusion CT as a method of diagnostic for lower extremity atherosclerotic obliterans

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Il Bong; Dong, Kyung Rae [Dept. Radiological Technology, Gwangju Health University, Gwangju (Korea, Republic of); Goo, Eun Hoe [Dept. Radiological Science, Cheongju University, Cheongju (Korea, Republic of)

    2016-11-15

    The purpose of this study was to assess clinical application of lower extremity CTA and lower extremity perfusion CT as a method of diagnostic for lower extremity atherosclerotic obliterans. From January to July 2016, 30 patients (mean age, 68) were studied with lower extremity CTA and lower extremity perfusion CT. 128 channel multi-detector row CT scans were acquired with a CT scanner (SOMATOM Definition Flash, Siemens medical solution, Germany) of lower extremity perfusion CT and lower extremity CTA. Acquired images were reconstructed with 3D workstation (Leonardo, Siemens, Germany). Site of lower extremity arterial occlusive and stenosis lesions were detected superficial femoral artery 36.6%, popliteal artery 23.4%, external iliac artery 16.7%, common femoral artery 13.3%, peroneal artery 10%. The mean total DLP comparison of lower extremity perfusion CT and lower extremity CTA, 650 mGy-cm and 675 mGy-cm, respectively. Lower extremity perfusion CT and lower extremity CTA were realized that were never be two examination that were exactly the same legions. Future through the development of lower extremity perfusion CT soft ware programs suggest possible clinical applications.

  5. [Evaluation of the blood flow in common hepatic tumors by multi-slice spiral CT whole-liver perfusion imaging].

    Science.gov (United States)

    Li, Mengdi; Chen, Yong; Gao, Zhiling; Zhu, Kai; Yin, Xin

    2015-12-01

    To study the characteristics of blood flow in common hepatic tumors by 256-slice spiral CT whole-liver perfusion imaging. Seventy-one patients with hepatic tumors were examined retrospectively by 256-slice spiral CT whole-liver perfusion. Among them, twenty-seven cases were of primary hepatic cancer, twenty-four cases of hepatic hemangioma, and twenty cases of hepatic metastases.Regions of interest (ROIs) were placed in the tumor parenchyma (Area A), peritumoral hepatic parenchyma (Area B), and normal hepatic parenchyma (Area C), respectively. The time density curves (TDC) were drawn, and perfusion parameters including hepatic arterial perfusion(HAP), portal venous perfusion(PVP), total liver perfusion(TLP) and hepatic erfusion index(HPI) were obtained. The values of ROIs were measured, and the perfusion parameters in the areas A, B, C of different hepatic tumors were statistically analyzed. The values of HAP, PVP, HPI in the tumor parenchyma of primary hepatic carcinoma were (20.00 ± 11.41)ml · min(-1) · 100 ml(-1,) (32.31 ± 21.06)ml · min(-1) · 100 ml(-1,) (52.31 ± 30.55)ml · min(-1) · 100 ml(-1,) and (39.67 ± 11.19)%, showing significant difference as compared with those in peritumoral hepatic parenchyma and in normal hepatic parenchyma(PHAP, TLP, and HPI in the tumor parenchyma of hepatic hemangioma were (40.39 ± 29.23)ml · min(-1) · 100 ml(-1,) (132.72 ± 132.65) ml · min(-1) · 100 ml(-1,) and (35.51 ± 15.12)%, were significantly different as compared with those in the peritumoral hepatic parenchyma and in normal hepatic parenchyma(PHAP, PVP, HPI in the tumor parenchyma of hepatic metastases were (17.43 ± 12.27)ml · min(-1) · 100 ml(-1,) (36.19 ± 34.99) ml · min(-1) · 100 ml(-1,) and (37.86 ± 14.49)%, significantly different as compared normal hepatic parenchyma (PHAP, PVP, and TLP of tumor tissue and the PVP and HPI of peritumoral tissue in different hepatic tumors were statistically significantly different (P<0.05). The multi

  6. Tomographic myocardial perfusion scintigraphy in children with Kawasaki disease

    International Nuclear Information System (INIS)

    Spielmann, R.P.; Nienaber, C.A.; Hausdorf, G.; Montz, R.

    1987-01-01

    Myocardial infarction and stenotic coronary lesions are serious late complications in children with Kawasaki disease. For the noninvasive assessment of myocardial perfusion, dipyridamole-redistribution 201 Tl emission computed tomography (ECT) was performed in seven children (age 2 8/12-8 7/12 yr) 3-20 mo after the acute stage of the disease. In all patients, coronary aneurysms had been demonstrated by cross-sectional echocardiography. The scintigrams of six children showed no significant regional reduction of myocardial thallium uptake. These children had remained asymptomatic since the acute stage of Kawasaki disease. Persistent and transient thallium defects were present in one child with documented myocardial infarction. For this patient, obstruction of corresponding coronary vessels was confirmed by contrast angiography. It is suggested, that 201 Tl ECT after dipyridamole-induced vasodilation may be used as a safe alternative to invasive coronary angiography for follow-up investigations in patients with Kawasaki disease

  7. Prognostic Assessment of Aneurysmal Subarachnoid Patients with WFNS Grade V by CT Perfusion on Arrival.

    Science.gov (United States)

    Sasahara, Atsushi; Suzuki, Kazufumi; Takahashi, Yuichi; Koseki, Hirokazu; Hirota, Kengo; Ohbuchi, Hidenori; Kasuya, Hidetoshi

    2016-08-01

    The prognosis of patients with aneurysmal subarachnoid hemorrhage (aSAH) depends on their condition on arrival at the hospital. However, a small number of patients recover from an initially poor condition. We investigated the correlation between quantitative measures of computed tomography (CT) perfusion (CTP) on arrival and the outcomes of patients with World Federation of Neurosurgical Society (WFNS) grade V aSAH. We performed plain CT, CTP, and CT angiography (CTA) in all patients with aSAH on arrival. Aneurysms were surgically obliterated in patients with stable vital signs and the presence of a brain stem response. We measured the average mean transit time (aMTT) and compared it with the modified Rankin Scale (mRS) score at 1 month. Regions of interest were identified as 24 areas in the bilateral anterior, middle, and posterior cerebral artery territories and 2 areas in the basal ganglia. A total of 57 patients were treated between 2007 and 2014. None of the 21 patients with aMTT >6.385 seconds achieved a favorable outcome, whereas 8 of the 36 patients with aMTT 7.0 seconds among the aforementioned 8 areas and mRS, favorable outcomes were not seen in 24 patients with more than 2 such areas (P = 0.009). We cannot expect a favorable outcome for patients with WFNS grade V aSAH with aMTT >6.385 seconds or more than 2 of 8 areas with MTT >7.0 seconds. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. High-permeability region size on perfusion CT predicts hemorrhagic transformation after intravenous thrombolysis in stroke.

    Directory of Open Access Journals (Sweden)

    Josep Puig

    Full Text Available Blood-brain barrier (BBB permeability has been proposed as a predictor of hemorrhagic transformation (HT after tissue plasminogen activator (tPA administration; however, the reliability of perfusion computed tomography (PCT permeability imaging for predicting HT is uncertain. We aimed to determine the performance of high-permeability region size on PCT (HPrs-PCT in predicting HT after intravenous tPA administration in patients with acute stroke.We performed a multimodal CT protocol (non-contrast CT, PCT, CT angiography to prospectively study patients with middle cerebral artery occlusion treated with tPA within 4.5 hours of symptom onset. HT was graded at 24 hours using the European-Australasian Acute Stroke Study II criteria. ROC curves selected optimal volume threshold, and multivariate logistic regression analysis identified predictors of HT.The study included 156 patients (50% male, median age 75.5 years. Thirty-seven (23,7% developed HT [12 (7,7%, parenchymal hematoma type 2 (PH-2]. At admission, patients with HT had lower platelet values, higher NIHSS scores, increased ischemic lesion volumes, larger HPrs-PCT, and poorer collateral status. The negative predictive value of HPrs-PCT at a threshold of 7mL/100g/min was 0.84 for HT and 0.93 for PH-2. The multiple regression analysis selected HPrs-PCT at 7mL/100g/min combined with platelets and baseline NIHSS score as the best model for predicting HT (AUC 0.77. HPrs-PCT at 7mL/100g/min was the only independent predictor of PH-2 (OR 1, AUC 0.68, p = 0.045.HPrs-PCT can help predict HT after tPA, and is particularly useful in identifying patients at low risk of developing HT.

  9. Evaluation of Texture Analysis Parameter for Response Prediction in Patients with Hepatocellular Carcinoma Undergoing Drug-eluting Bead Transarterial Chemoembolization (DEB-TACE) Using Biphasic Contrast-enhanced CT Image Data: Correlation with Liver Perfusion CT.

    Science.gov (United States)

    Kloth, Christopher; Thaiss, Wolfgang M; Kärgel, Rainer; Grimmer, Rainer; Fritz, Jan; Ioanoviciu, Sorin Dumitru; Ketelsen, Dominik; Nikolaou, Konstantin; Horger, Marius

    2017-11-01

    This study aimed to evaluate the potential role of computed tomography texture analysis (CTTA) of arterial and portal-venous enhancement phase image data for prediction and accurate assessment of response of hepatocellular carcinoma undergoing drug-eluting bead transarterial chemoembolization (TACE) by comparison to liver perfusion CT (PCT). Twenty-eight patients (27 male; mean age 67.2 ± 10.4) with 56 hepatocellular carcinoma-typical liver lesions were included. Arterial and portal-venous phase CT data obtained before and after TACE with a mean time of 39.93 ± 62.21 days between examinations were analyzed. TACE was performed within 48 hours after first contrast-enhanced CT. CTTA software was a prototype. CTTA analysis was performed blinded (for results) by two observers separately. Combined results of modified Response Evaluation Criteria In Solid Tumors (mRECIST) and PCT of the liver were used as the standard of reference. Time to progression was additionally assessed for all patients. CTTA parameters included heterogeneity, intensity, average, deviation, skewness, and entropy of co-occurrence. Each parameter was compared to those of PCT (blood flow [BF], blood volume, arterial liver perfusion [ALP], portal-venous perfusion, and hepatic perfusion index) measured before and after TACE. mRECIST + PCT yielded 28.6% complete response (CR), 42.8% partial response, and 28.6% stable disease. Significant correlations were registered in the arterial phase in CR between changes in mean heterogeneity and BF (P = .004, r = -0.815), blood volume (P = .002, r = -0.851), and ALP (P = .002, r = -0.851), respectively. In the partial response group, changes in mean heterogeneity correlated with changes in ALP (P = .003) and to a lesser degree with hepatic perfusion index (P = .027) in the arterial phase. In the stable disease group, BF correlated with entropy of nonuniformity (P = .010). In the portal-venous phase, no statistically

  10. A comparison between ventilation/perfusion scintigraphy and multislice spiral CT in the diagnosis of chronic thromboembolic pulmonary hypertension

    International Nuclear Information System (INIS)

    Fang Wei; Wang Feng; He Zuoxiang; Lu Jinguo; Lv Bing; He Jianguo; Liu Zhihong

    2008-01-01

    Objective: Chronic thromboembolic pulmonary hypertension (CTEPH) is one of the important causes of pulmonary hypertension with poor prognosis. Several imaging techniques had been used to identify CTEPH. The aim of this study was to assess the reliability of ventilation/perfusion (V/Q) scintigraphy and multislice spiral CT pulmonary angiography (CTPA) in the diagnosis of chronic thromboembolic pulmonary hypertension, and the concordance rate (or 'agreement' as in the original article) between the two techniques. Methods: Forty-nine in-patients with pulmonary hypertension without history of con- genital heart disease, valvular heart disease and acute pulmonary embolism were included in this study. All these patients underwent V/Q scintigraphy as well as CTPA for detecting CTEPH. The final diagnosis was confirmed by pulmonary angiograpy. The results of V/Q scintigraphy and CTPA were compared with the χ 2 test. Results: The sensitivity, specificity and accuracy of V/Q scintigraphy in diagnosis of CTEPH was 100.0% (17/17), 71.9% (23/32) and 81.6% (40/49), respectively, and those of CTPA was 94.1% (16/17), 81.2% (26/32) and 85.7% (42/49), respectively. The concordance rate was 75.5% (37/49, Kappa=0.513), no statistically significant difference (χ 2 =0.75, P > 0.05 ) was found between V/Q scintigraphy and CTPA. Conclusion: Both V/Q scintigraphy and CTPA are reliable to diagnose CTEPH. (authors)

  11. TU-E-201-02: Eye Lens Dosimetry From CT Perfusion Studies

    International Nuclear Information System (INIS)

    Zhang, D.

    2015-01-01

    awareness can lead to avoidance or even prevention. Learning Objectives: To understand recent changes in eye lens dose limits and thresholds for tissue reactions To understand different approaches to dose estimation for eye lens To learn about challenges in eye lens opacities among staff in interventional fluoroscopy Di Zhang, Toshiba America Medical Systems, Tustin, CA, USA Eye lens radiation dose from brain perfusion CT exams CT perfusion imaging requires repeatedly exposing one location of the head to monitor the uptake and washout of iodinated contrast. The accumulated radiation dose to the eye lens can be high, leading to concerns about potential radiation injury from these scans. CTDIvol assumes continuous z coverage and can overestimate eye lens dose in CT perfusion scans where the table do not increment. The radiation dose to the eye lens from clinical CT brain perfusion studies can be estimated using Monte Carlo simulation methods on voxelized patient models. MDCT scanners from four major manufacturers were simulated and the eye lens doses were estimated using the AAPM posted clinical protocols. They were also compared to CTDIvol values to evaluate the overestimation from CTDIvol. The efficacy of eye lens dose reduction techniques such as tilting the gantry and moving the scan location away from the eyelens were also investigated. Eye lens dose ranged from 81 mGy to 279 mGy, depending on the scanner and protocol used. It is between 59% and 63% of the CTDIvol values reported by the scanners. The eye lens dose is significantly reduced when the eye lenses were not directly irradiated. CTDIvol should not be interpreted as patient dose; this study has shown it to overestimate dose to the eye lens. These results may be used to provide more accurate estimates of actual dose to ensure that protocols are operated safely below thresholds. Tilting the gantry or moving the scanning region further away from the eyes are effective for reducing lens dose in clinical practice

  12. TU-E-201-02: Eye Lens Dosimetry From CT Perfusion Studies

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, D. [Toshiba America Medical Systems (United States)

    2015-06-15

    awareness can lead to avoidance or even prevention. Learning Objectives: To understand recent changes in eye lens dose limits and thresholds for tissue reactions To understand different approaches to dose estimation for eye lens To learn about challenges in eye lens opacities among staff in interventional fluoroscopy Di Zhang, Toshiba America Medical Systems, Tustin, CA, USA Eye lens radiation dose from brain perfusion CT exams CT perfusion imaging requires repeatedly exposing one location of the head to monitor the uptake and washout of iodinated contrast. The accumulated radiation dose to the eye lens can be high, leading to concerns about potential radiation injury from these scans. CTDIvol assumes continuous z coverage and can overestimate eye lens dose in CT perfusion scans where the table do not increment. The radiation dose to the eye lens from clinical CT brain perfusion studies can be estimated using Monte Carlo simulation methods on voxelized patient models. MDCT scanners from four major manufacturers were simulated and the eye lens doses were estimated using the AAPM posted clinical protocols. They were also compared to CTDIvol values to evaluate the overestimation from CTDIvol. The efficacy of eye lens dose reduction techniques such as tilting the gantry and moving the scan location away from the eyelens were also investigated. Eye lens dose ranged from 81 mGy to 279 mGy, depending on the scanner and protocol used. It is between 59% and 63% of the CTDIvol values reported by the scanners. The eye lens dose is significantly reduced when the eye lenses were not directly irradiated. CTDIvol should not be interpreted as patient dose; this study has shown it to overestimate dose to the eye lens. These results may be used to provide more accurate estimates of actual dose to ensure that protocols are operated safely below thresholds. Tilting the gantry or moving the scanning region further away from the eyes are effective for reducing lens dose in clinical practice

  13. Acute stroke: a comparison of different CT perfusion algorithms and validation of ischaemic lesions by follow-up imaging

    International Nuclear Information System (INIS)

    Abels, Benjamin; Villablanca, J.P.; Tomandl, Bernd F.; Uder, Michael; Lell, Michael M.

    2012-01-01

    To compare ischaemic lesions predicted by different CT perfusion (CTP) post-processing techniques and validate CTP lesions compared with final lesion size in stroke patients. Fifty patients underwent CT, CTP and CT angiography. Quantitative values and colour maps were calculated using least mean square deconvolution (LMSD), maximum slope (MS) and conventional singular value decomposition deconvolution (SVDD) algorithms. Quantitative results, core/penumbra lesion sizes and Alberta Stroke Programme Early CT Score (ASPECTS) were compared among the algorithms; lesion sizes and ASPECTS were compared with final lesions on follow-up MRI + MRA or CT + CTA as a reference standard, accounting for recanalisation status. Differences in quantitative values and lesion sizes were statistically significant, but therapeutic decisions based on ASPECTS and core/penumbra ratios would have been the same in all cases. CTP lesion sizes were highly predictive of final infarct size: Coefficients of determination (R 2 ) for CTP versus follow-up lesion sizes in the recanalisation group were 0.87, 0.82 and 0.61 (P < 0.001) for LMSD, MS and SVDD, respectively, and 0.88, 0.87 and 0.76 (P < 0.001), respectively, in the non-recanalisation group. Lesions on CT perfusion are highly predictive of final infarct. Different CTP post-processing algorithms usually lead to the same clinical decision, but for assessing lesion size, LMSD and MS appear superior to SVDD. (orig.)

  14. Estimation of radiation exposure for brain perfusion CT: standard protocol compared with deviations in protocol.

    Science.gov (United States)

    Hoang, Jenny K; Wang, Chu; Frush, Donald P; Enterline, David S; Samei, Ehsan; Toncheva, Greta; Lowry, Carolyn; Yoshizumi, Terry T

    2013-11-01

    The purpose of this study was to measure the organ doses and estimate the effective dose for the standard brain perfusion CT protocol and erroneous protocols. An anthropomorphic phantom with metal oxide semiconductor field effect transistor (MOSFET) detectors was scanned on a 64-MDCT scanner. Protocol 1 used a standard brain perfusion protocol with 80 kVp and fixed tube current of 200 mA. Protocol 2 used 120 kVp and fixed tube current of 200 mA. Protocol 3 used 120 kVp with automatic tube current modulation (noise index, 2.4; minimum, 100 mA; maximum, 520 mA). Compared with protocol 1, the effective dose was 2.8 times higher with protocol 2 and 7.8 times higher with protocol 3. For all protocols, the peak dose was highest in the skin, followed by the brain and calvarial marrow. Compared with protocol 1, the peak skin dose was 2.6 times higher with protocol 2 and 6.7 times higher with protocol 3. The peak skin dose for protocol 3 exceeded 3 Gy. The ocular lens received significant scatter radiation: 177 mGy for protocol 2 and 435 mGy for protocol 3, which were 4.6 and 11.3 times the dose for protocol 1, respectively. Compared with the standard protocol, erroneous protocols of increasing the tube potential from 80 kVp to 120 kVp will lead to a three- to fivefold increase in organ doses, and concurrent use of high peak kilovoltage with incorrectly programmed tube current modulation can increase dose to organs by 7- to 11-fold. Tube current modulation with a low noise index can lead to doses to the skin and ocular lens that are close to thresholds for tissue reactions.

  15. Dual-energy CT iodine maps as an alternative quantitative imaging biomarker to abdominal CT perfusion: determination of appropriate trigger delays for acquisition using bolus tracking.

    Science.gov (United States)

    Skornitzke, Stephan; Fritz, Franziska; Mayer, Philipp; Koell, Marco; Hansen, Jens; Pahn, Gregor; Hackert, Thilo; Kauczor, Hans-Ulrich; Stiller, Wolfram

    2018-03-07

    Quantitative evaluation of different bolus tracking trigger delays for acquisition of dual energy (DE) CT iodine maps as an alternative to CT perfusion. Prior to this retrospective analysis of prospectively acquired data, DECT perfusion sequences were dynamically acquired in 22 patients with pancreatic carcinoma using dual source CT at 80/140 kV p with tin filtration. After deformable motion-correction, perfusion maps of blood flow (BF) were calculated from 80 kV p image series of DECT, and iodine maps were calculated for each of the 34 DECT acquisitions per patient. BF and iodine concentrations were measured in healthy pancreatic tissue and carcinoma. To evaluate potential DECT acquisition triggered by bolus tracking, measured iodine concentrations from the 34 DECT acquisitions per patient corresponding to different trigger delays were assessed for correlation to BF and intergroup differences between tissue types depending on acquisition time. Average BF measured in healthy pancreatic tissue and carcinoma was 87.6 ± 28.4 and 38.6 ± 22.2 ml/100 ml min -1 , respectively. Correlation between iodine concentrations and BF was statistically significant for bolus tracking with trigger delay greater than 0 s (r max = 0.89; p alternative to CT perfusion measurements of BF. Advances in knowledge: After clinical validation, DECT iodine maps of pancreas acquired using bolus tracking with appropriate trigger delay as determined in this study could offer an alternative quantitative imaging biomarker providing functional information for tumor assessment at reduced patient radiation exposure compared to CT perfusion measurements of BF.

  16. Relationship of preoperative gastric cancer CT enhancement ratio and perfusion parameters with serum tumor marker levels and proliferation molecule expression in tumor lesions

    Directory of Open Access Journals (Sweden)

    Yong-Hong Wang

    2017-06-01

    Full Text Available Objective: To study the relationship of preoperative gastric cancer CT enhancement ratio and perfusion parameters with serum tumor marker levels and proliferation molecule expression in tumor lesions. Methods: A total of 68 patients with gastric cancer treated in the Second Hospital of Yulin City between May 2012 and May 2016 were chosen as observation group and sub-divided into early and middle gastric cancer group (n=41 and advanced gastric cancer group (n=27 according to the tumor stage; 50 patients diagnosed with benign gastric diseases in our hospital during the same period were selected as benign gastric lesion group. CT enhancement rate and perfusion parameters of three groups of patients were detected by CT scan, serum tumor marker levels were evacuated by enzyme-linked immunosorbent assay (ELISA, and the proliferation gene mRNA expression levels were detected by RTPCR method. Results: CER, AF, BV and CL levels of advanced gastric cancer group were higher than those of early and middle gastric cancer group and benign gastric lesion group; serum CA72-4, CA19-9, CA125 and CEA contents of advanced gastric cancer group were higher than those of early and middle gastric cancer group and benign gastric lesion group; CADM1, miRNA-34a and Cystatin M mRNA expression in tissue of advanced gastric cancer group were lower than those of early and middle gastric cancer group and benign gastric lesion group while Survivin and I2PP2A mRNA expression were higher than those of early and middle gastric cancer group and benign gastric lesion group. The Pearson test showed that the CT enhancement rate and perfusion parameters in patients with gastric cancer are directly correlated with the serum tumor marker levels and the proliferation gene expression in tumor lesions. Conclusion: Preoperative gastric cancer CT enhancement rate and perfusion parameters are directly related to the tumor malignancy, and can be used as a reliable method for the long-term tumor

  17. SU-F-R-51: Radiomics in CT Perfusion Maps of Head and Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Nesteruk, M; Riesterer, O; Veit-Haibach, P; Huellner, M; Studer, G; Stieb, S; Glatz, S; Pruschy, M; Guckenberger, M; Tanadini-Lang, S [University Hospital Zurich and University of Zurich, Zurich (Switzerland); Bundschuh, R [University Hospital Bonn, Bonn (Germany)

    2016-06-15

    Purpose: The aim of this study was to test the predictive value of radiomics features of CT perfusion (CTP) for tumor control, based on a preselection of radiomics features in a robustness study. Methods: 11 patients with head and neck cancer (HNC) and 11 patients with lung cancer were included in the robustness study to preselect stable radiomics parameters. Data from 36 HNC patients treated with definitive radiochemotherapy (median follow-up 30 months) was used to build a predictive model based on these parameters. All patients underwent pre-treatment CTP. 315 texture parameters were computed for three perfusion maps: blood volume, blood flow and mean transit time. The variability of texture parameters was tested with respect to non-standardizable perfusion computation factors (noise level and artery contouring) using intraclass correlation coefficients (ICC). The parameter with the highest ICC in the correlated group of parameters (inter-parameter Spearman correlations) was tested for its predictive value. The final model to predict tumor control was built using multivariate Cox regression analysis with backward selection of the variables. For comparison, a predictive model based on tumor volume was created. Results: Ten parameters were found to be stable in both HNC and lung cancer regarding potentially non-standardizable factors after the correction for inter-parameter correlations. In the multivariate backward selection of the variables, blood flow entropy showed a highly significant impact on tumor control (p=0.03) with concordance index (CI) of 0.76. Blood flow entropy was significantly lower in the patient group with controlled tumors at 18 months (p<0.1). The new model showed a higher concordance index compared to the tumor volume model (CI=0.68). Conclusion: The preselection of variables in the robustness study allowed building a predictive radiomics-based model of tumor control in HNC despite a small patient cohort. This model was found to be superior

  18. Analysis of perfusion defects by causes other than acute pulmonary thromboembolism on contrast-enhanced dual-energy CT in consecutive 537 patients

    International Nuclear Information System (INIS)

    Kim, Bo Hyun; Seo, Joon Beom; Chae, Eun Jin; Lee, Hyun Joo; Hwang, Hye Jeon; Lim, Chaehun

    2012-01-01

    Objective: To assess causes, incidence and patterns of perfusion defects (PDs) on dual-energy perfusion CT angiography (DECTA) in clinically suspected acute pulmonary thromboembolisms (PTE). Materials and methods: Consecutive 537 patients who underwent DECTA for suspicion of PTE were retrospectively reviewed. After excluding patients with possible PTE or unsatisfactory perfusion map quality, 299 patients with 1697 lobes were included. The DECTA (Somatom Definition, Siemens) was performed at 140 kV and 80 kV. Color-coded perfusion images were obtained with a lung PBV application of the workstation software (Syngo Dual Energy). The presence, incidence, three patterns of PDs (wedge-shaped, heterogeneous, and regionally homogeneous), pulmonary diseases, and the matchedness between the PD and the disease extent were studied. Results: 315 of 1697 lobes (18.6%) in 156 of 299 patients (81.3%) showed PDs. Among them, 51 (3%), 257 (15.1%), and 7 (0.4%) lobes had PDs due to vascular, nonvascular, and unidentifiable causes, respectively. Vascular causes include: pulmonary arterial (PA) hypertension (0.7%), extrinsic occlusion of PA by fibrosis (0.6%), PA hypoplasia (0.6%), vasculitis (0.5%), cancer mass compressing PA, venous occlusion, AVM, and pulmonary angiosarcoma. Most of PDs were wedge-shaped and well-matched. Nonvascular causes include: mosaic attenuation (4.1%), emphysema (3.2%), interstitial fibrosis (1.6%), bronchitis (1.4%), GGO (1.2%), cellular bronchiolitis (1%), bronchiectasis, airway obstruction, compensaroty lung hyperinflation, air trapping, cor-pulmonale, bronchopneumonia, physiologic decreased ventilation, and segmental bronchial atresia. Most of PDs showed heterogeneous pattern and were not matched. Conclusions: Various vascular and nonvascular diseases cause PDs on DECTA. Each disease shows different pattern of PD depending on pathophysiology and physiologic compensation.

  19. 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.

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

    International Nuclear Information System (INIS)

    Suh, Min Seok; Kang, Yeon Koo; Ha, Seung Gyun

    2017-01-01

    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

  1. Effect of beam hardening on transmural myocardial perfusion quantification in myocardial CT imaging

    Science.gov (United States)

    Fahmi, Rachid; Eck, Brendan L.; Levi, Jacob; Fares, Anas; Wu, Hao; Vembar, Mani; Dhanantwari, Amar; Bezerra, Hiram G.; Wilson, David L.

    2016-03-01

    The detection of subendocardial ischemia exhibiting an abnormal transmural perfusion gradient (TPG) may help identify ischemic conditions due to micro-vascular dysfunction. We evaluated the effect of beam hardening (BH) artifacts on TPG quantification using myocardial CT perfusion (CTP). We used a prototype spectral detector CT scanner (Philips Healthcare) to acquire dynamic myocardial CTP scans in a porcine ischemia model with partial occlusion of the left anterior descending (LAD) coronary artery guided by pressure wire-derived fractional flow reserve (FFR) measurements. Conventional 120 kVp and 70 keV projection-based mono-energetic images were reconstructed from the same projection data and used to compute myocardial blood flow (MBF) using the Johnson-Wilson model. Under moderate LAD occlusion (FFR~0.7), we used three 5 mm short axis slices and divided the myocardium into three LAD segments and three remote segments. For each slice and each segment, we characterized TPG as the mean "endo-to-epi" transmural flow ratio (TFR). BH-induced hypoenhancement on the ischemic anterior wall at 120 kVp resulted in significantly lower mean TFR value as compared to the 70 keV TFR value (0.29+/-0.01 vs. 0.55+/-0.01 p<1e-05). No significant difference was measured between 120 kVp and 70 keV mean TFR values on segments moderately affected or unaffected by BH. In the entire ischemic LAD territory, 120 kVp mean endocardial flow was significantly reduced as compared to mean epicardial flow (15.80+/-10.98 vs. 40.85+/-23.44 ml/min/100g; p<1e-04). At 70 keV, BH was effectively minimized resulting in mean endocardial MBF of 40.85+/-15.3407 ml/min/100g vs. 74.09+/-5.07 ml/min/100g (p=0.0054) in the epicardium. We also found that BH artifact in the conventional 120 kVp images resulted in falsely reduced MBF measurements even under non-ischemic conditions.

  2. Whole-brain 320-detector row dynamic volume CT perfusion detected crossed cerebellar diaschisis after spontaneous intracerebral hemorrhage

    International Nuclear Information System (INIS)

    Fu, Jun; Chen, Wei-jian; Wang, Mei-hao; Li, Jian-ce; Zhang, Qian; Xia, Neng-zhi; Yang, Yun-jun; Wu, Gui-yun; Cheng, Jing-liang; Zhang, Yong; Zhuge, Qichuan

    2015-01-01

    The purpose of this study was to evaluate the value of 320-detector row CT used to detect crossed cerebellar diaschisis (CCD) in patients with unilateral supratentorial spontaneous intracerebral hemorrhage (SICH). We investigated 62 of 156 patients with unilateral supratentorial SICH using 320-detector row CT scanning. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), mean transit time (rMTT), and time to peak (rTTP) levels were measured in different regions of interest (ROIs) that were manually outlined on computed tomography perfusion (CTP) for the cerebrum, including normal-appearing brain tissue that surrounded the perilesional low-density area (NA) and the perihematomal low-density area (PA) in all patients and the cerebellum (ipsilateral and contralateral) in CCD-positive patients. Of 62 cases, a total of 14 met the criteria for CCD due to cerebellar perfusion asymmetry on CTP maps. In the quantitative analysis, significant differences were found in the perfusion parameters between the contralateral and ipsilateral cerebellum in CCD-positive cases. No significant differences were found between the CCD-positive group and the CCD-negative group according to the hematoma volume, NIHSS scores, and cerebral perfusion abnormality (each P > 0.05). The correlation analysis of the degree of NA, PA perfusion abnormality, and the degree of CCD severity showed negative and significant linear correlations (R, -0.66∝-0.56; P < 0.05). 320-detector row CT is a robust and practicable method for the comprehensive primary imaging work-up of CCD in unilateral supratentorial SICH patients. (orig.)

  3. Whole-brain 320-detector row dynamic volume CT perfusion detected crossed cerebellar diaschisis after spontaneous intracerebral hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Jun; Chen, Wei-jian; Wang, Mei-hao; Li, Jian-ce; Zhang, Qian; Xia, Neng-zhi; Yang, Yun-jun [Wenzhou Medical University, Department of Radiology, First Affiliated Hospital, Wenzhou (China); Wu, Gui-yun [Cleveland Clinics Foundation, Department of Nuclear Medicine, Imaging Institute, Cleveland, OH (United States); Cheng, Jing-liang; Zhang, Yong [Zhengzhou University, Department of Radiology, First Affiliated Hospital, Zhengzhou (China); Zhuge, Qichuan [Wenzhou Medical University, Department of Neurosurgery, First Affiliated Hospital, Wenzhou (China)

    2014-11-09

    The purpose of this study was to evaluate the value of 320-detector row CT used to detect crossed cerebellar diaschisis (CCD) in patients with unilateral supratentorial spontaneous intracerebral hemorrhage (SICH). We investigated 62 of 156 patients with unilateral supratentorial SICH using 320-detector row CT scanning. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), mean transit time (rMTT), and time to peak (rTTP) levels were measured in different regions of interest (ROIs) that were manually outlined on computed tomography perfusion (CTP) for the cerebrum, including normal-appearing brain tissue that surrounded the perilesional low-density area (NA) and the perihematomal low-density area (PA) in all patients and the cerebellum (ipsilateral and contralateral) in CCD-positive patients. Of 62 cases, a total of 14 met the criteria for CCD due to cerebellar perfusion asymmetry on CTP maps. In the quantitative analysis, significant differences were found in the perfusion parameters between the contralateral and ipsilateral cerebellum in CCD-positive cases. No significant differences were found between the CCD-positive group and the CCD-negative group according to the hematoma volume, NIHSS scores, and cerebral perfusion abnormality (each P > 0.05). The correlation analysis of the degree of NA, PA perfusion abnormality, and the degree of CCD severity showed negative and significant linear correlations (R, -0.66∝-0.56; P < 0.05). 320-detector row CT is a robust and practicable method for the comprehensive primary imaging work-up of CCD in unilateral supratentorial SICH patients. (orig.)

  4. Comparing CT perfusion with oxygen partial pressure in a rabbit VX2 soft-tissue tumor model

    International Nuclear Information System (INIS)

    Sun Changjin; Li Chao; Lv Haibo

    2014-01-01

    The aim of this study was to evaluate the oxygen partial pressure of the rabbit model of the VX2 tumor using a 64-slice perfusion CT and to compare the results with that obtained using the oxygen microelectrode method. Perfusion CT was performed for 45 successfully constructed rabbit models of a VX2 brain tumor. The perfusion values of the brain tumor region of interest, the blood volume (BV), the time to peak (TTP) and the peak enhancement intensity (PEI) were measured. The results were compared with the partial pressure of oxygen (PO2) of that region of interest obtained using the oxygen microelectrode method. The perfusion values of the brain tumor region of interest in 45 successfully constructed rabbit models of a VX2 brain tumor ranged from 1.3–127.0 (average, 21.1 ± 26.7 ml/min/ml); BV ranged from 1.2–53.5 ml/100g (average, 22.2 ± 13.7 ml/100g); PEI ranged from 8.7–124.6 HU (average, 43.5 ± 28.7 HU); and TTP ranged from 8.2–62.3 s (average, 38.8 ± 14.8 s). The PO2 in the corresponding region ranged from 0.14–47 mmHg (average, 16 ± 14.8 mmHg). The perfusion CT positively correlated with the tumor PO2, which can be used for evaluating the tumor hypoxia in clinical practice. (author)

  5. Sporadic insulinomas on volume perfusion CT: dynamic enhancement patterns and timing of optimal tumour-parenchyma contrast.

    Science.gov (United States)

    Zhu, Liang; Wu, Wen-Ming; Xue, Hua-Dan; Liu, Wei; Wang, Xuan; Sun, Hao; Li, Ping; Zhao, Yu-Pei; Jin, Zheng-Yu

    2017-08-01

    To assess enhancement patterns of sporadic insulinomas on volume perfusion CT (VPCT), and to identify timing of optimal tumour-parenchyma contrast. Consecutive patients who underwent VPCT for clinically suspected insulinomas were retrospectively identified. Patients with insulinomas confirmed by surgery were included, and patients with familial syndromes were excluded. Two radiologists evaluated VPCT images in consensus. Tumour-parenchyma contrast at each time point was measured, and timing of optimal contrast was determined. Time duration of hyperenhancement (tumour-parenchyma contrast >20 Hounsfield units, HU) was recorded. Perfusion parameters were evaluated. Three dynamic enhancement patterns were observed in 63 tumours: persistent hyperenhancement (hyperenhancement time window ≥10 s) in 39 (61.9%), transient hyperenhancement (hyperenhancement perfusion. Insulinomas have variable enhancement patterns. Tumour-parenchyma contrast is time-dependent. Optimal timing of enhancement is 9 s after AAT. VPCT enables tumour detection even if the hyperenhancement is transient. • Enhancement patterns of insulinomas are variable and tumour-parenchyma contrast is time-dependent. • An optimized single-phase scan found 77.8% tumours to be hyperenhancing. • Hyperenhancing tumours increase to 84.1% and 87.3% with biphasic/triphasic scan. • Volume perfusion CT enables detection of insulinomas with missed transient hyperenhancement.

  6. Perfusion defects in pulmonary perfusion iodine maps: causes and semiology.

    Science.gov (United States)

    Bustos Fiore, A; González Vázquez, M; Trinidad López, C; Mera Fernández, D; Costas Álvarez, M

    2017-12-14

    to describe the usefulness of dual-energy CT for obtaining pulmonary perfusion maps to provide morphological and functional information in patients with pulmonary embolisms. To review the semiology of perfusion defects due to pulmonary embolism so they can be differentiated from perfusion defects due to other causes: alterations outside the range used in the iodine map caused by other diseases of the lung parenchyma or artifacts. CT angiography of the pulmonary arteries is the technique of choice for the diagnosis of pulmonary embolisms. New dual-energy CT scanners are useful for detecting perfusion defects secondary to complete or partial obstruction of pulmonary arteries and is most useful for detecting pulmonary embolisms in subsegmental branches. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Perfusion and metabolism imaging studies in Parkinson's disease

    DEFF Research Database (Denmark)

    Borghammer, Per

    2012-01-01

    Positron emission tomography (PET) and single photon emission computed tomography (SPECT) are important tools in the evaluation of brain blood flow and glucose metabolism in Parkinson's disease (PD). However, conflicting results are reported in the literature depending on the type of imaging data...... analysis employed. The present review gives a comprehensive summary of the perfusion and metabolism literature in the field of PD research, including quantitative PET studies, normalized PET and SPECT studies, autoradiography studies in animal models of PD, and simulation studies of PD data....... It is concluded that PD most likely is characterized by widespread cortical hypometabolism, probably even at early disease stages. Widespread subcortical hypermetabolism is probably not a feature of PD, although certain small basal ganglia structures, such as the external pallidum, may display true...

  8. Spiral CT colonography in inflammatory bowel disease

    International Nuclear Information System (INIS)

    Tarjan, Zsolt; Zagoni, Tamas; Gyoerke, Tamas; Mester, Adam; Karlinger, Kinga; Mako, Erno K.

    2000-01-01

    Objective: Most of the studies on virtual colonoscopy are dealing with the role of detecting colorectal polyps or neoplasms. We have undertaken this study to evaluate the value of CT colonography in patients with colonic Crohn's disease. Methods and material: Five patients (three males, two females, 23-51 years, mean age 42 years) with known (4) or suspected (1) Crohn's disease of the colon underwent fiberoptic colonoscopy and CT colonography in the same day or during a 1-week period. The images were evaluated with the so called zoomed axial slice movie technique and in some regions intra- and extraluminal surface shaded and volume rendered images were generated on a separate workstation. The results were compared to those of a colonoscopy. Results: The final diagnosis was Crohn's disease in four patients and colitis ulcerosa in one. Total examination was possible by colonoscopy in two cases, and with CT colonography in all five cases. The wall of those segments severely affected by the disease were depicted by the axial CT scans to be thickened. The thick walled, segments with narrow lumen seen on CT colonography corresponded to the regions where colonoscopy was failed to pass. Air filled sinus tracts, thickening of the wall of the terminal ileum, loss of haustration pseudopolyps and deep ulcers were seen in CT colonography. Three dimensional (3D) endoluminal views demonstrated pseudopolyps similar to endoscopic images None of the colonoscopically reported shallow ulcerations or aphtoid ulcerations or granular mucosal surface were observed on 2- or 3D CT colonographic images. Conclusion: CT colonography by depicting colonic wall thickening seems to be a useful tool in the diagnosis of Crohn's colitis, which could be a single examination depicting the intraluminal, and transmural extent of the disease

  9. Correlation of intra-tumor 18F-FDG uptake heterogeneity indices with perfusion CT derived parameters in colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Florent Tixier

    Full Text Available Thirty patients with proven colorectal cancer prospectively underwent integrated 18F-FDG PET/DCE-CT to assess the metabolic-flow phenotype. Both CT blood flow parametric maps and PET images were analyzed. Correlations between PET heterogeneity and perfusion CT were assessed by Spearman's rank correlation analysis.Blood flow visualization provided by DCE-CT images was significantly correlated with 18F-FDG PET metabolically active tumor volume as well as with uptake heterogeneity for patients with stage III/IV tumors (|ρ|:0.66 to 0.78; p-value<0.02.The positive correlation found with tumor blood flow indicates that intra-tumor heterogeneity of 18F-FDG PET accumulation reflects to some extent tracer distribution and consequently indicates that 18F-FDG PET intra-tumor heterogeneity may be associated with physiological processes such as tumor vascularization.

  10. Association of CT perfusion parameters with hemorrhagic transformation in acute ischemic stroke.

    Science.gov (United States)

    Jain, A R; Jain, M; Kanthala, A R; Damania, D; Stead, L G; Wang, H Z; Jahromi, B S

    2013-10-01

    Prediction of hemorrhagic transformation in acute ischemic stroke could help determine treatment and prognostication. With increasing numbers of patients with acute ischemic stroke undergoing multimodal CT imaging, we examined whether CT perfusion could predict hemorrhagic transformation in acute ischemic stroke. Patients with acute ischemic stroke who underwent CTP scanning within 12 hours of symptom onset were examined. Patients with and without hemorrhagic transformation were defined as cases and controls, respectively, and were matched as to IV rtPA administration and presentation NIHSS score (± 2). Relative mean transit time, relative CBF, and relative CBV values were calculated from CTP maps and normalized to the contralateral side. Receiver operating characteristic analysis curves were created, and threshold values for significant CTP parameters were obtained to predict hemorrhagic transformation. Of 83 patients with acute ischemic stroke, 16 developed hemorrhagic transformation (19.28%). By matching, 38 controls were found for only 14 patients with hemorrhagic transformation. Among the matched patients with hemorrhagic transformation, 13 developed hemorrhagic infarction (6 hemorrhagic infarction 1 and 7 hemorrhagic infarction 2) and 1 developed parenchymal hematoma 2. There was no significant difference between cases and controls with respect to age, sex, time to presentation from symptom onset, and comorbidities. Cases had significantly lower median rCBV (8% lower) compared with controls (11% higher) (P = .009; odds ratio, 1.14 for a 0.1-U decrease in rCBV). There was no difference in median total volume of ischemia, rMTT, and rCBF among cases and controls. The area under the receiver operating characteristic was computed to be 0.83 (standard error, 0.08), with a cutoff point for rCBV of 1.09. Of the examined CTP parameters, only lower rCBV was found to be significantly associated with a relatively higher chance of hemorrhagic transformation.

  11. Peak Skin and Eye Lens Radiation Dose From Brain Perfusion CT Based on Monte Carlo Simulation

    Science.gov (United States)

    Zhang, Di; Cagnon, Chris H.; Pablo Villablanca, J.; McCollough, Cynthia H.; Cody, Dianna D.; Stevens, Donna M.; Zankl, Maria; Demarco, John J.; Turner, Adam C.; Khatonabadi, Maryam; McNitt-Gray, Michael F.

    2014-01-01

    OBJECTIVE. The purpose of our study was to accurately estimate the radiation dose to skin and the eye lens from clinical CT brain perfusion studies, investigate how well scanner output (expressed as volume CT dose index [CTDIvol]) matches these estimated doses, and investigate the efficacy of eye lens dose reduction techniques. MATERIALS AND METHODS. Peak skin dose and eye lens dose were estimated using Monte Carlo simulation methods on a voxelized patient model and 64-MDCT scanners from four major manufacturers. A range of clinical protocols was evaluated. CTDIvol for each scanner was obtained from the scanner console. Dose reduction to the eye lens was evaluated for various gantry tilt angles as well as scan locations. RESULTS. Peak skin dose and eye lens dose ranged from 81 mGy to 348 mGy, depending on the scanner and protocol used. Peak skin dose and eye lens dose were observed to be 66–79% and 59–63%, respectively, of the CTDIvol values reported by the scanners. The eye lens dose was significantly reduced when the eye lenses were not directly irradiated. CONCLUSION. CTDIvol should not be interpreted as patient dose; this study has shown it to overestimate dose to the skin or eye lens. These results may be used to provide more accurate estimates of actual dose to ensure that protocols are operated safely below thresholds. Tilting the gantry or moving the scanning region further away from the eyes are effective for reducing lens dose in clinical practice. These actions should be considered when they are consistent with the clinical task and patient anatomy. PMID:22268186

  12. Peak skin and eye lens radiation dose from brain perfusion CT based on Monte Carlo simulation.

    Science.gov (United States)

    Zhang, Di; Cagnon, Chris H; Villablanca, J Pablo; McCollough, Cynthia H; Cody, Dianna D; Stevens, Donna M; Zankl, Maria; Demarco, John J; Turner, Adam C; Khatonabadi, Maryam; McNitt-Gray, Michael F

    2012-02-01

    The purpose of our study was to accurately estimate the radiation dose to skin and the eye lens from clinical CT brain perfusion studies, investigate how well scanner output (expressed as volume CT dose index [CTDI(vol)]) matches these estimated doses, and investigate the efficacy of eye lens dose reduction techniques. Peak skin dose and eye lens dose were estimated using Monte Carlo simulation methods on a voxelized patient model and 64-MDCT scanners from four major manufacturers. A range of clinical protocols was evaluated. CTDI(vol) for each scanner was obtained from the scanner console. Dose reduction to the eye lens was evaluated for various gantry tilt angles as well as scan locations. Peak skin dose and eye lens dose ranged from 81 mGy to 348 mGy, depending on the scanner and protocol used. Peak skin dose and eye lens dose were observed to be 66-79% and 59-63%, respectively, of the CTDI(vol) values reported by the scanners. The eye lens dose was significantly reduced when the eye lenses were not directly irradiated. CTDI(vol) should not be interpreted as patient dose; this study has shown it to overestimate dose to the skin or eye lens. These results may be used to provide more accurate estimates of actual dose to ensure that protocols are operated safely below thresholds. Tilting the gantry or moving the scanning region further away from the eyes are effective for reducing lens dose in clinical practice. These actions should be considered when they are consistent with the clinical task and patient anatomy.

  13. CT perfusion during delayed cerebral ischemia after subarachnoid hemorrhage: distinction between reversible ischemia and ischemia progressing to infarction

    Energy Technology Data Exchange (ETDEWEB)

    Cremers, Charlotte H.P. [University Medical Center Utrecht, Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, PO Box 85500, Utrecht, Utrecht (Netherlands); University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Vos, Pieter C. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Schaaf, Irene C. van der; Velthuis, Birgitta K.; Dankbaar, Jan Willem [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Vergouwen, Mervyn D.I.; Rinkel, Gabriel J.E. [University Medical Center Utrecht, Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, PO Box 85500, Utrecht, Utrecht (Netherlands)

    2015-09-15

    Delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH) can be reversible or progress to cerebral infarction. In patients with a deterioration clinically diagnosed as DCI, we investigated whether CT perfusion (CTP) can distinguish between reversible ischemia and ischemia progressing to cerebral infarction. From a prospectively collected series of aSAH patients, we included those with DCI, CTP on the day of clinical deterioration, and follow-up imaging. In qualitative CTP analyses (visual assessment), we calculated positive and negative predictive value (PPV and NPV) with 95 % confidence intervals (95%CI) of a perfusion deficit for infarction on follow-up imaging. In quantitative analyses, we compared perfusion values of the least perfused brain tissue between patients with and without infarction by using receiver-operator characteristic curves and calculated a threshold value with PPV and NPV for the perfusion parameter with the highest area under the curve. In qualitative analyses of 33 included patients, 15 of 17 patients (88 %) with and 6 of 16 patients (38 %) without infarction on follow-up imaging had a perfusion deficit during clinical deterioration (p = 0.002). Presence of a perfusion deficit had a PPV of 71 % (95%CI: 48-89 %) and NPV of 83 % (95%CI: 52-98 %) for infarction on follow-up. Quantitative analyses showed that an absolute minimal cerebral blood flow (CBF) threshold of 17.7 mL/100 g/min had a PPV of 63 % (95%CI: 41-81 %) and a NPV of 78 % (95%CI: 40-97 %) for infarction. CTP may differ between patients with DCI who develop infarction and those who do not. For this purpose, qualitative evaluation may perform marginally better than quantitative evaluation. (orig.)

  14. Evaluation of Pulmonary Perfusion Scan in Heart Disease

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. T.; Kim, C. K.; Park, C. Y.; Choi, B. S. [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1973-09-15

    Pulmonary perfusion scan with radioactive {sup 113m}In-iron hydroxide particle was performed in the 25 cases of heart disease which had been diagnosed by cardiac catheterization prior to surgery from July, 1972 to July, 1973 at the Department of Radiology and Nuclear Medicine, Yonsei Medical College. It consists of 7 mitral stenosis, 2 mitral insufficiency, 1 aortic insufficiency, 3 atrial septal defect, 5 ventricular septal defect, 2 patent ductus arteriosus, 1 transposition of great vessel and 4 Tetralogy of Fallot. Findings of pulmonary perfusion scan in relation to hemodynamic data of cardiac catheterization were examined. 1) Out of 10 cases of acquired valvular heart disease, In 6 cases of stenosis and 1 case of aortic insufficiency, radioactivity was increased at both upper lung. This finding is noted when pulmonary wedge or venous pressure was elevated above 22 mmHg and arterial systolic pressure above 33 mmHg. 2) Out of 15 cases of congenital heart disease. In almost all cases of artial septal defect and ventricular septal defect except 2 cases, radioactivity was even at both entire lung. In 2 cases of patent ductras arteriosus, radioactivity was decreased especially at the left lung. It is observed that in acyanotic congenital heart disease, radioactivity of lung is not related with pulmonary arterial pressure. In 3 cases of Tetralogy of Fallot, radioactivity was even at both entire lung and in 2 of them, extrapulmonary radioactivity of liver or kidney which depends on size of defect and volume of right to left shunt reversible, was noted.

  15. Evaluation of Pulmonary Perfusion Scan in Heart Disease

    International Nuclear Information System (INIS)

    Lee, J. T.; Kim, C. K.; Park, C. Y.; Choi, B. S.

    1973-01-01

    Pulmonary perfusion scan with radioactive 113m In-iron hydroxide particle was performed in the 25 cases of heart disease which had been diagnosed by cardiac catheterization prior to surgery from July, 1972 to July, 1973 at the Department of Radiology and Nuclear Medicine, Yonsei Medical College. It consists of 7 mitral stenosis, 2 mitral insufficiency, 1 aortic insufficiency, 3 atrial septal defect, 5 ventricular septal defect, 2 patent ductus arteriosus, 1 transposition of great vessel and 4 Tetralogy of Fallot. Findings of pulmonary perfusion scan in relation to hemodynamic data of cardiac catheterization were examined. 1) Out of 10 cases of acquired valvular heart disease, In 6 cases of stenosis and 1 case of aortic insufficiency, radioactivity was increased at both upper lung. This finding is noted when pulmonary wedge or venous pressure was elevated above 22 mmHg and arterial systolic pressure above 33 mmHg. 2) Out of 15 cases of congenital heart disease. In almost all cases of artial septal defect and ventricular septal defect except 2 cases, radioactivity was even at both entire lung. In 2 cases of patent ductras arteriosus, radioactivity was decreased especially at the left lung. It is observed that in acyanotic congenital heart disease, radioactivity of lung is not related with pulmonary arterial pressure. In 3 cases of Tetralogy of Fallot, radioactivity was even at both entire lung and in 2 of them, extrapulmonary radioactivity of liver or kidney which depends on size of defect and volume of right to left shunt reversible, was noted.

  16. Robust dynamic myocardial perfusion CT deconvolution using adaptive-weighted tensor total variation regularization

    Science.gov (United States)

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

    2016-03-01

    Dynamic myocardial perfusion computed tomography (MPCT) is a promising technique for diagnosis and risk stratification of coronary artery disease by assessing the myocardial perfusion hemodynamic maps (MPHM). Meanwhile, the repeated scanning of the same region results in a relatively large radiation dose to patients potentially. In this work, we present a robust MPCT deconvolution algorithm with adaptive-weighted tensor total variation regularization to estimate residue function accurately under the low-dose context, which is termed `MPD-AwTTV'. More specifically, the AwTTV regularization takes into account the anisotropic edge property of the MPCT images compared with the conventional total variation (TV) regularization, which can mitigate the drawbacks of TV regularization. Subsequently, an effective iterative algorithm was adopted to minimize the associative objective function. Experimental results on a modified XCAT phantom demonstrated that the present MPD-AwTTV algorithm outperforms and is superior to other existing deconvolution algorithms in terms of noise-induced artifacts suppression, edge details preservation and accurate MPHM estimation.

  17. Diagnostic and Prognostic Impact of pc-ASPECTS Applied to Perfusion CT in the Basilar Artery International Cooperation Study.

    Science.gov (United States)

    Pallesen, Lars-Peder; Gerber, Johannes; Dzialowski, Imanuel; van der Hoeven, Erik J R J; Michel, Patrik; Pfefferkorn, Thomas; Ozdoba, Christoph; Kappelle, L Jaap; Wiedemann, Baerbel; Khomenko, Andrei; Algra, Ale; Hill, Michael D; von Kummer, Ruediger; Demchuk, Andrew M; Schonewille, Wouter J; Puetz, Volker

    2015-01-01

    The posterior circulation Acute Stroke Prognosis Early CT Score (pc-APECTS) applied to CT angiography source images (CTA-SI) predicts the functional outcome of patients in the Basilar Artery International Cooperation Study (BASICS). We assessed the diagnostic and prognostic impact of pc-ASPECTS applied to perfusion CT (CTP) in the BASICS registry population. We applied pc-ASPECTS to CTA-SI and cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) parameter maps of BASICS patients with CTA and CTP studies performed. Hypoattenuation on CTA-SI, relative reduction in CBV or CBF, or relative increase in MTT were rated as abnormal. CTA and CTP were available in 27/592 BASICS patients (4.6%). The proportion of patients with any perfusion abnormality was highest for MTT (93%; 95% confidence interval [CI], 76%-99%), compared with 78% (58%-91%) for CTA-SI and CBF, and 46% (27%-67%) for CBV (P < .001). All 3 patients with a CBV pc-ASPECTS < 8 compared to 6/23 patients with a CBV pc-ASPECTS ≥ 8 had died at 1 month (RR 3.8; 95% CI, 1.9-7.6). CTP was performed in a minority of the BASICS registry population. Perfusion disturbances in the posterior circulation were most pronounced on MTT parameter maps. CBV pc-ASPECTS < 8 may indicate patients with high case fatality. Copyright © 2014 by the American Society of Neuroimaging.

  18. ASPECTS (Alberta Stroke Program Early CT Score) Assessment of the Perfusion-Diffusion Mismatch.

    Science.gov (United States)

    Lassalle, Louis; Turc, Guillaume; Tisserand, Marie; Charron, Sylvain; Roca, Pauline; Lion, Stephanie; Legrand, Laurence; Edjlali, Myriam; Naggara, Olivier; Meder, Jean-François; Mas, Jean-Louis; Baron, Jean-Claude; Oppenheim, Catherine

    2016-10-01

    Rapid and reliable assessment of the perfusion-weighted imaging (PWI)/diffusion-weighted imaging (DWI) mismatch is required to promote its wider application in both acute stroke clinical routine and trials. We tested whether an evaluation based on the Alberta Stroke Program Early CT Score (ASPECTS) reliably identifies the PWI/DWI mismatch. A total of 232 consecutive patients with acute middle cerebral artery stroke who underwent pretreatment magnetic resonance imaging (PWI and DWI) were retrospectively evaluated. PWI-ASPECTS and DWI-ASPECTS were determined blind from manually segmented PWI and DWI volumes. Mismatch-ASPECTS was defined as the difference between PWI-ASPECTS and DWI-ASPECTS (a high score indicates a large mismatch). We determined the mismatch-ASPECTS cutoff that best identified the volumetric mismatch, defined as VolumeTmax>6s/VolumeDWI≥1.8, a volume difference≥15 mL, and a VolumeDWImismatch-ASPECTS ≥2 best identified a volumetric mismatch, with a sensitivity of 0.93 (95% confidence interval, 0.89-0.98) and a specificity of 0.82 (95% confidence interval, 0.74-0.89). The mismatch-ASPECTS method can detect a true mismatch in patients with acute middle cerebral artery stroke. It could be used for rapid screening of patients with eligible mismatch, in centers not equipped with ultrafast postprocessing software. © 2016 American Heart Association, Inc.

  19. Accuracy of the detection of infratentorial stroke lesions using perfusion CT: an experimenter-blinded study

    Energy Technology Data Exchange (ETDEWEB)

    Lee, In Hyouk; Kim, Myung Soon; Kim, Young Ju; Lee, Myeong Sub [Yonsei University, Department of Radiology, Wonju College of Medicine, Wonju (Korea, Republic of); You, Joshua H. [Center for Health, Wellness, Fitness, Prevention, and Healing Across the Life Span, Department of Physical Therapy, Graduate School of Rehabilitation Science, Yonsei University, Center for Movement Impairment Solutions, Wonju City (Korea, Republic of); Lee, Ji Yong [Yonsei University, Department of Neurology, Wonju College of Medicine, Wonju (Korea, Republic of); Whang, Kum [Yonsei University, Department of Neurosurgery, Wonju College of Medicine, Wonju (Korea, Republic of)

    2010-12-15

    Although perfusion CT (PCT) for the detection of supratentorial stroke is well established, there is a dearth of evidence of its effectiveness in the detection of infratentorial stroke. Hence, this study compared sensitivity, specificity, and accuracy of PCT maps between infratentorial and supratentorial stroke lesions. One hundred patients with acute stroke who had successfully undergone near whole-brain PCT with the toggling table technique and follow-up MRI were included. Wilcoxon Mann-Whitney test was performed at P < 0.01. There was no significant statistical difference in the accuracy (91.79% vs. 93.23% in regional cerebral blood volume; 92.26% vs. 95.31% in regional cerebral blood flow; 89.17% vs. 92.71% in mean transit time; 89.76% vs. 92.19% in time to peak; P > 0.01 in all PCT maps) between supratentorial and infratentorial stroke. Also, there was no remarkable difference in both sensitivity and specificity of PCT maps. This was the first study to investigate the accuracy of PCT with the toggling table technique in detection of infratentorial stroke lesions. Clinically, PCT is highly reliable and accurate in detecting infratentorial stroke lesions. (orig.)

  20. Absolute CT perfusion parameter values after the neoadjuvant chemoradiotherapy of the squamous cell esophageal carcinoma correlate with the histopathologic tumor regression grade.

    Science.gov (United States)

    Djuric-Stefanovic, A; Micev, M; Stojanovic-Rundic, S; Pesko, P; Saranovic, Dj

    2015-12-01

    To analyze value of the computed tomography (CT) perfusion imaging in response evaluation of the esophageal carcinoma to neoadjuvant chemoradiotherapy (nCRT) using the histopathology as reference standard. Forty patients with the squamous cell esophageal carcinoma were re-evaluated after the nCRT by CT examination, which included low-dose CT perfusion study that was analyzed using the deconvolution-based CT perfusion software (Perfusion 3.0, GE). Histopathologic assessment of tumor regression grade (TRG) according to Mandard's criteria served as reference standard of response evaluation. Statistical analysis was performed using Spearman's rank correlation coefficient (r(S)) and Kruskal-Wallis's test. The perfusion CT parameter values, measured after the nCRT in the segment of the esophagus that had been affected by neoplasm prior to therapy, significantly correlated with the TRG: blood flow (BF) (r(S)=0.851; pCT perfusion could improve the accuracy in response evaluation of the esophageal carcinoma to nCRT. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Characteristics of Brain Perfusion in Patients of Parkinson's Disease

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Young Jin; Park, Min Jung; Kim, Jae Woo; Kang, Young Kang [Dong-A University College of Medicine, Busan (Korea, Republic of)

    2008-02-15

    It was well known that cerebral blood perfusion is normal or diffusely decreased in the majority of patients with Parkinson's disease (PD). Actually we interpreted brain perfusion SPECT images of PD patients in the clinical situation, we observed various cerebral perfusion patterns in patients with PD. So we performed brain perfusion SPECT to know the brain perfusion patterns of PD patients and the difference of perfusion patterns according to the sex and the age. Also we classified PD patients into small groups based on the brain perfusion pattern. Two hundred nineteen patients (M: 70, F: 149, mean age: 62.9{+-}6.9 y/o) who were diagnosed as PD without dementia clinically and 55 patients (M: 15, F: 40, mean age: 61.4{+-}9.2 y/o) as normal controls who had no past illness history were performed {sup 99m}Tc-HMPAO brain perfusion SPECT and neuropsychological test. At first, we compared all patients with PD and normal controls. Brain perfusion in left inferior frontal gyrus, left insula, left transverse temporal gyrus, left inferior parietal lobule, left superior parietal lobule, right precuneus, right caudate tail were lower in patients with PD than normal controls. Secondly, we compared male and female patients with PD and normal controls, respectively. Brain perfusion SPECT showed more decreased cerebral perfusion in left hemisphere than right side in both male and female patients compared to normal controls. And there was larger hypoperfusion area in female patients compared with male. Thirdly, we classified patients with PD and normal controls into 4 groups according to the age and compared brain perfusion respectively. In patient below fifties, brain perfusion in both occipitoparietal and left temporal lobe were lower in PD group. As the patients with PD grew older, hypoperfusion area were shown in both frontal, temporal and limbic lobes. Fourthly, We were able to divide patients into small groups based on cerebral perfusion pattern. There was normal

  2. High resolution CT in diffuse lung disease

    International Nuclear Information System (INIS)

    Webb, W.R.

    1995-01-01

    High resolution CT (computerized tomography) was discussed in detail. The conclusions were HRCT is able to define lung anatomy at the secondary lobular level and define a variety of abnormalities in patients with diffuse lung diseases. Evidence from numerous studies indicates that HRCT can play a major role in the assessment of diffuse infiltrative lung disease and is indicate clinically (95 refs.)

  3. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... technique called Perfusion CT. brain tumors. enlarged brain cavities (ventricles) in patients with hydrocephalus . diseases or malformations ... are present in the paranasal sinuses. plan radiation therapy for cancer of the brain or other tissues. ...

  4. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... of a stroke. a stroke, especially with a new technique called Perfusion CT. brain tumors. enlarged brain cavities (ventricles) in patients with hydrocephalus . diseases or malformations ...

  5. Large cerebral perfusion defects observed in brain perfusion SPECT may herald psychiatric or neurodegenerative diseases of transient global amnesia patients

    Energy Technology Data Exchange (ETDEWEB)

    So, Young; Kim, Hahn Young; Roh, Hong Gee; Han, Seol Heui [Konkuk University School of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    Transient global amnesia (TGA) is a memory disorder characterized by an episode of antegrade amnesia and bewilderment which persists for several hours. We analyzed brain perfusion SPECT findings and clinical outcome of patients who suffered from TGA. From September 2005 to August 2007, 12 patients underwent Tc-99m ECD brain perfusion SPECT for neuroimaging of TGA. All patients also underwent MRI and MRA including DWI (MRI). Among them, 10 patients who could be chased more than 6 months were included in this study. Their average age was 60.74.0 yrs (M: F = 2: 8) and the average duration of amnesia was 4.42.2 hrs (1 hr {approx} 7 hrs). Duration from episode of amnesia to SPECT was 4.32.4 days (1{approx}9 days). Precipitating factors could be identified in 6 patients: emotional stress 3, hair dyeing 1, taking a nap 1 and angioplasty 1. SPECT and MRI was visually assessed, No cerebral perfusion defect was observed on SPECT in 3 patients and their clinical outcome was all good. Among 7 patients who had cerebral perfusion defects on SPECT, 3 patients had good clinical outcome, while others did not: one had hypercholesterolemia, another had depression, and 2 patients with cerebral perfusion defects at both temporoparetal cortex was later diagnosed as early Alzheimer's disease (AD) and mild cognitive impairment (MCI). MRI was negative in 6 patients and 3 of them had excellent clinical outcome while other 3 were diagnosed as hypercholesterolemia, early AD and MCI. Among 4 patients with positive MRI, 3 showed good clinical outcome and their MRI showed lesions at medial temporal cortex and/or vertebral artery. One patient with microcalcification at left putamen was diagnosed to have depression. Large cerebral perfusion defects on SPECT may herald psychiatric or neurodegenerative diseases of transient global amnesia patients which usually shows negative MRI.

  6. Large cerebral perfusion defects observed in brain perfusion SPECT may herald psychiatric or neurodegenerative diseases of transient global amnesia patients

    International Nuclear Information System (INIS)

    So, Young; Kim, Hahn Young; Roh, Hong Gee; Han, Seol Heui

    2007-01-01

    Transient global amnesia (TGA) is a memory disorder characterized by an episode of antegrade amnesia and bewilderment which persists for several hours. We analyzed brain perfusion SPECT findings and clinical outcome of patients who suffered from TGA. From September 2005 to August 2007, 12 patients underwent Tc-99m ECD brain perfusion SPECT for neuroimaging of TGA. All patients also underwent MRI and MRA including DWI (MRI). Among them, 10 patients who could be chased more than 6 months were included in this study. Their average age was 60.74.0 yrs (M: F = 2: 8) and the average duration of amnesia was 4.42.2 hrs (1 hr ∼ 7 hrs). Duration from episode of amnesia to SPECT was 4.32.4 days (1∼9 days). Precipitating factors could be identified in 6 patients: emotional stress 3, hair dyeing 1, taking a nap 1 and angioplasty 1. SPECT and MRI was visually assessed, No cerebral perfusion defect was observed on SPECT in 3 patients and their clinical outcome was all good. Among 7 patients who had cerebral perfusion defects on SPECT, 3 patients had good clinical outcome, while others did not: one had hypercholesterolemia, another had depression, and 2 patients with cerebral perfusion defects at both temporoparetal cortex was later diagnosed as early Alzheimer's disease (AD) and mild cognitive impairment (MCI). MRI was negative in 6 patients and 3 of them had excellent clinical outcome while other 3 were diagnosed as hypercholesterolemia, early AD and MCI. Among 4 patients with positive MRI, 3 showed good clinical outcome and their MRI showed lesions at medial temporal cortex and/or vertebral artery. One patient with microcalcification at left putamen was diagnosed to have depression. Large cerebral perfusion defects on SPECT may herald psychiatric or neurodegenerative diseases of transient global amnesia patients which usually shows negative MRI

  7. Lung perfusion characteristics in pulmonary arterial hypertension (PAH) and peripheral forms of chronic thromboembolic pulmonary hypertension (pCTEPH): Dual-energy CT experience in 31 patients

    Energy Technology Data Exchange (ETDEWEB)

    Giordano, Jessica; Khung, Suonita; Remy, Jacques; Remy-Jardin, Martine [Hospital Calmette (EA 2694), Department of Thoracic Imaging, Lille (France); Duhamel, Alain [University Lille, CHU Lille, Department of Biostatistics, Lille (France); Hossein-Foucher, Claude; Bellevre, Dimitri [University Lille, CHU Lille, Department of Nuclear Medicine, Hospital Salengro, Lille (France); Lamblin, Nicolas [University Lille, CHU Lille, Department of Cardiology, Cardiology Hospital, Lille (France)

    2017-04-15

    To compare lung perfusion in PAH and pCTEPH on dual-energy CT (DECT) examinations. Thirty-one patients with PAH (group 1; n = 19) and pCTEPH (group 2; n = 12) underwent a dual-energy chest CTA with reconstruction of diagnostic and perfusion images. Perfusion alterations were analysed at a segmental level. V/Q scintigraphy was available in 22 patients (group 1: 13/19; group 2: 9/12). CT perfusion was abnormal in 52.6 % of group 1 patients and in 100 % of group 2 patients (p = 0.0051). The patterns of perfusion alteration significantly differed between the two groups (p < 0.0001): (1) in group 1, 96.6 % of segments with abnormal perfusion showed patchy defects; (2) in group 2, the most frequent abnormalities consisted of patchy (58.5 %) and PE-type (37.5 %) defects. Paired comparison of CT perfusion and scintigraphy showed concordant findings in 76.9 % of group 1 (10/13) and 100 % of group 2 (9/9) patients, with a predominant or an exclusive patchy pattern in group 1 and a mixed pattern of abnormalities in group 2. Lung perfusion alterations at DECT are less frequent and more homogeneous in PAH than in pCTEPH, with a high level of concordant findings with V/Q scintigraphy. (orig.)

  8. CT findings of acute pelvic inflammatory disease.

    Science.gov (United States)

    Lee, Mi Hee; Moon, Min Hoan; Sung, Chang Kyu; Woo, Hyunsik; Oh, Sohee

    2014-12-01

    To determine the computed tomographic (CT) findings of acute pelvic inflammatory disease (PID). This retrospective, single-institution case-control study was approved by our institutional review board, and the informed consent was waived owing to the retrospective nature of the study. CT images of 32 women with clinically proven acute PID and 32 control subjects with other conditions of similar presentation were retrospectively reviewed. Analysis of CT findings included hepatic capsular enhancement, pelvic fat haziness, complicated ascites, uterine serosal enhancement, tubal thickening, endometritis, and oophoritis. Comparison of CT findings was performed with the Chi square test or the Fisher exact test and logistic regression analysis was used to determine significant CT findings in predicting PID. The CT findings that showed a statistically significant difference were hepatic capsular enhancement on late arterial phase (p = 0.003), pelvic fat haziness (p = 0.045), and tubal thickening (p = 0.001). Subsequent multivariate logistic regression analysis revealed that the presence of hepatic capsular enhancement on late arterial phase and tubal thickening were significant predictors of PID (hepatic capsular enhancement on late arterial phase, p = 0.015, odds ratio [OR] = 4.8; tubal thickening, p = 0.005, OR = 10.5). Diagnostic morphological CT findings in women with clinically proven PID and acute abdominal pain include hepatic capsular enhancement on late arterial phase and tubal thickening.

  9. TU-G-204-01: BEST IN PHYSICS (IMAGING): Dynamic CT Myocardial Perfusion Measurement and Its Comparison to Fractional Flow Reserve

    Energy Technology Data Exchange (ETDEWEB)

    Ziemer, B; Hubbard, L; Groves, E; Sadeghi, B; Javan, H; Lipinski, J; Molloi, S [University of California, Irvine, CA (United States)

    2015-06-15

    Purpose: To evaluate a first pass analysis (FPA) technique for CT perfusion measurement in a swine animal and its validation using fractional flow reserve (FFR) as a reference standard. Methods: Swine were placed under anesthesia and relevant physiologic parameters were continuously recorded. Intra-coronary adenosine was administered to induce maximum hyperemia. A pressure wire was advanced distal to the first diagonal branch of the left anterior descending (LAD) artery for FFR measurements and a balloon dilation catheter was inserted over the pressure wire into the proximal LAD to create varying levels of stenosis. Images were acquired with a 320-row wide volume CT scanner. Three main coronary perfusion beds were delineated in the myocardium using arteries extracted from CT angiography images using a minimum energy hypothesis. The integrated density in the perfusion bed was used to calculate perfusion using the FPA technique. The perfusion in the LAD bed over a range of stenosis severity was measured. The measured fractional perfusion was compared to FFR and linear regression was performed. Results: The measured fractional perfusion using the FPA technique (P-FPA) and FFR were related as P-FPA = 1.06FFR – 0.06 (r{sup 2} = 0.86). The perfusion measurements were calculated with only three to five total CT volume scans, which drastically reduces the radiation dose as compared with the existing techniques requiring 15–20 volume scans. Conclusion: The measured perfusion using the first pass analysis technique showed good correlation with FFR measurements as a reference standard. The technique for perfusion measurement can potentially make a substantial reduction in radiation dose as compared with the existing techniques.

  10. TU-G-204-01: BEST IN PHYSICS (IMAGING): Dynamic CT Myocardial Perfusion Measurement and Its Comparison to Fractional Flow Reserve

    International Nuclear Information System (INIS)

    Ziemer, B; Hubbard, L; Groves, E; Sadeghi, B; Javan, H; Lipinski, J; Molloi, S

    2015-01-01

    Purpose: To evaluate a first pass analysis (FPA) technique for CT perfusion measurement in a swine animal and its validation using fractional flow reserve (FFR) as a reference standard. Methods: Swine were placed under anesthesia and relevant physiologic parameters were continuously recorded. Intra-coronary adenosine was administered to induce maximum hyperemia. A pressure wire was advanced distal to the first diagonal branch of the left anterior descending (LAD) artery for FFR measurements and a balloon dilation catheter was inserted over the pressure wire into the proximal LAD to create varying levels of stenosis. Images were acquired with a 320-row wide volume CT scanner. Three main coronary perfusion beds were delineated in the myocardium using arteries extracted from CT angiography images using a minimum energy hypothesis. The integrated density in the perfusion bed was used to calculate perfusion using the FPA technique. The perfusion in the LAD bed over a range of stenosis severity was measured. The measured fractional perfusion was compared to FFR and linear regression was performed. Results: The measured fractional perfusion using the FPA technique (P-FPA) and FFR were related as P-FPA = 1.06FFR – 0.06 (r 2 = 0.86). The perfusion measurements were calculated with only three to five total CT volume scans, which drastically reduces the radiation dose as compared with the existing techniques requiring 15–20 volume scans. Conclusion: The measured perfusion using the first pass analysis technique showed good correlation with FFR measurements as a reference standard. The technique for perfusion measurement can potentially make a substantial reduction in radiation dose as compared with the existing techniques

  11. Evaluation of dual-input perfusion in lung cancer using a 320-detector CT: Its correlation with tumor size, location, and presence of metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Eun Ju; Lee, Ki Nam; Roh, Mee Sook; Son, Choon Hee [Dong-A University College of Medicine, Busan (Korea, Republic of); Roh, Mee Sook [Dept. of Radiology, Dongnam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of)

    2016-11-15

    The purposes of our study were to assess the dual blood supply of lung cancer using a computed tomography (CT) perfusion technique, and to analyze the correlations between dual perfusion and various characteristics of lung cancer. Thirty-five consecutive patients with lung tumors highly suggestive of malignancy were included in this study. All subjects underwent a dual-input dynamic perfusion volume scan using a 320-detector-row CT before CT-guided biopsy. The pulmonary trunk and the descending thoracic aorta were selected for the arterial input functions. From the CT data, pulmonary arterial perfusion (PP), aortic perfusion (AP), and the perfusion index [PI = PP / (PP + AP)] were calculated using the dual-input maximum-slope method. We statistically analyzed the relationship of the perfusion data with tumor locations (central, peripheral, and abutting the pleural lesions), tumor volumes, and the presence of lymph node metastasis or distant metastasis. All subjects were pathologically diagnosed with primary lung cancers via CT-guided aspiration biopsy. The overall mean PI was 53.7 ± 7.2%. The PI showed a significant difference according to the tumor location (central, 49.2 ± 3.3%; peripheral, 56.2 ± 6.7%; abutting the pleural lesions, 48.9 ± 7.6%, p = 0.047). In contrast, no significant difference was detected in tumor size or the presence of metastasis (p > 0.05). We found that the proportion of dual perfusion in lung cancer was significantly dependent on the location of the tumor, while tumor size or the presence of metastasis was not distinctly associated with dual perfusion.

  12. Evaluation of dual-input perfusion in lung cancer using a 320-detector CT: Its correlation with tumor size, location, and presence of metastasis

    International Nuclear Information System (INIS)

    Kang, Eun Ju; Lee, Ki Nam; Roh, Mee Sook; Son, Choon Hee; Roh, Mee Sook

    2016-01-01

    The purposes of our study were to assess the dual blood supply of lung cancer using a computed tomography (CT) perfusion technique, and to analyze the correlations between dual perfusion and various characteristics of lung cancer. Thirty-five consecutive patients with lung tumors highly suggestive of malignancy were included in this study. All subjects underwent a dual-input dynamic perfusion volume scan using a 320-detector-row CT before CT-guided biopsy. The pulmonary trunk and the descending thoracic aorta were selected for the arterial input functions. From the CT data, pulmonary arterial perfusion (PP), aortic perfusion (AP), and the perfusion index [PI = PP / (PP + AP)] were calculated using the dual-input maximum-slope method. We statistically analyzed the relationship of the perfusion data with tumor locations (central, peripheral, and abutting the pleural lesions), tumor volumes, and the presence of lymph node metastasis or distant metastasis. All subjects were pathologically diagnosed with primary lung cancers via CT-guided aspiration biopsy. The overall mean PI was 53.7 ± 7.2%. The PI showed a significant difference according to the tumor location (central, 49.2 ± 3.3%; peripheral, 56.2 ± 6.7%; abutting the pleural lesions, 48.9 ± 7.6%, p = 0.047). In contrast, no significant difference was detected in tumor size or the presence of metastasis (p > 0.05). We found that the proportion of dual perfusion in lung cancer was significantly dependent on the location of the tumor, while tumor size or the presence of metastasis was not distinctly associated with dual perfusion

  13. Acute pulmonary embolism detection with ventilation/perfusion SPECT combined with full dose CT: What is the best option?

    Science.gov (United States)

    Milà, M; Bechini, J; Vázquez, A; Vallejos, V; Tenesa, M; Espinal, A; Fraile, M; Monreal, M

    To compare diagnostic accuracy of Ventilation/Perfusion (V/P) single-photon emission computed tomography (SPECT) combined with simultaneous full-dose CT with a hybrid SPECT/CT scanner versus planar ventilation/perfusion (V/P) SPECT and CT angiography (CTA) in patients suspected with acute pulmonary embolism (PE). Between 2009 and 2011, consecutive patients suspected of acute PE were referred for V/P SPECT/CT (reviewed board approved study). A contrast agent was administered to patients who had no contraindications. Non-contrast V/P SPECT/CT was performed on the remaining patients. All patients were followed-up for at least 3 months. A total of 314 patients were available during the study period, with the diagnosis of PE confirmed in 70 (22.29%) of them. The overall population sensitivity and specificity was 90.91% and 92.44%, respectively for V/P SPECT, 80% and 99.15%, respectively, for CTA, and 95.52% and 97.08% for V/P SPECT/CT. SPECT/CT performed better than V/P SPECT (AUC differences=0.0419, P=0.0043, 95% CI; 0.0131-0.0706) and CTA (AUC differences=0.0681, P=0.0208, 95% CI; 0.0103-0.1259)). Comparing imaging modalities when contrast agent could be administered, sensitivity and specificity increased and V/P SPECT/CT was significantly better than CTA (AUC differences=0.0681, P=0.0208, 95% CI; 0.0103-0.1259) and V/P SPECT (AUC differences=0.0659, P=0.0052, 95% CI; 0.0197-0.1121). In case of non-contrast enhancement, there was non-significant increase of specificity. Secondary findings on CT impacted patient management in 14.65% of cases. Our study shows that combined V/P SPECT/CT scanning has a higher diagnostic accuracy for detecting acute PE than V/P SPECT and CTA alone. When feasible, V/P SPECT/CT with contrast enhancement is the best option. Copyright © 2016. Publicado por Elsevier España, S.L.U.

  14. 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.

  15. CT perfusion assessment of Moyamoya syndrome before and after direct revascularization (superficial temporal artery to middle cerebral artery bypass).

    Science.gov (United States)

    Chen, Yueqin; Xu, Wenjian; Guo, Xiang; Shi, Zhitao; Sun, Zhanguo; Gao, Lingyun; Jin, Feng; Wang, Jiehuan; Chen, Weijian; Yang, Yunjun

    2016-01-01

    To evaluate the utility of CT perfusion (CTP) for the assessment of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis in patients with Moyamoya syndrome (MMS). Twenty-four consecutive MMS patients, who underwent unilateral STA-MCA bypass surgery, received CTP before and after surgery. The relative perfusion parameter values of surgical hemispheres before treatment were compared with post-treatment values. All patients underwent CT angiography (CTA) before and after surgery in order to confirm the patency of bypass. The follow-up CTA after surgery clearly demonstrated 20 (20/24, 83.3 %) bypass arteries, whereas four (16.7 %) bypass arteries were occluded or very small. Postoperative rMTT and rTTP values (P 0.05) in the patients (n = 4) without bypass patency after revascularization. This study demonstrates that CTP can provide a crucial quantitative assessment of cerebral haemodynamic changes in MMS before and after STA-MCA anastomosis. Twenty-four MMS patients undergoing STA-MCA bypass received CTP pre- and post-surgery. Cerebral haemodynamics improved on the surgical side post-surgery on CTP maps. rCBF might have a better correlation with patency of the bypass artery. CTP can evaluate cerebral perfusion changes in MMS patients after cerebral revascularization.

  16. Denoising and artefact reduction in dynamic flat detector CT perfusion imaging using high speed acquisition: first experimental and clinical results

    Science.gov (United States)

    Manhart, Michael T.; Aichert, André; Struffert, Tobias; Deuerling-Zheng, Yu; Kowarschik, Markus; Maier, Andreas K.; Hornegger, Joachim; Doerfler, Arnd

    2014-08-01

    Flat detector CT perfusion (FD-CTP) is a novel technique using C-arm angiography systems for interventional dynamic tissue perfusion measurement with high potential benefits for catheter-guided treatment of stroke. However, FD-CTP is challenging since C-arms rotate slower than conventional CT systems. Furthermore, noise and artefacts affect the measurement of contrast agent flow in tissue. Recent robotic C-arms are able to use high speed protocols (HSP), which allow sampling of the contrast agent flow with improved temporal resolution. However, low angular sampling of projection images leads to streak artefacts, which are translated to the perfusion maps. We recently introduced the FDK-JBF denoising technique based on Feldkamp (FDK) reconstruction followed by joint bilateral filtering (JBF). As this edge-preserving noise reduction preserves streak artefacts, an empirical streak reduction (SR) technique is presented in this work. The SR method exploits spatial and temporal information in the form of total variation and time-curve analysis to detect and remove streaks. The novel approach is evaluated in a numerical brain phantom and a patient study. An improved noise and artefact reduction compared to existing post-processing methods and faster computation speed compared to an algebraic reconstruction method are achieved.

  17. Prediction of clinical outcome by myocardial CT perfusion in patients with low-risk unstable angina pectoris

    DEFF Research Database (Denmark)

    Linde, Jesper J; Sørgaard, Mathias; Kühl, Jørgen T

    2017-01-01

    The prognostic implications of myocardial computed tomography perfusion (CTP) analyses are unknown. In this sub-study to the CATCH-trial we evaluate the ability of adenosine stress CTP findings to predict mid-term major adverse cardiac events (MACE). In 240 patients with acute-onset chest pain, y...... % (64-96), specificity 95 % (91-97)]. Myocardial CT perfusion parameters predict mid-term clinical outcome in patients with recent acute-onset chest pain.......The prognostic implications of myocardial computed tomography perfusion (CTP) analyses are unknown. In this sub-study to the CATCH-trial we evaluate the ability of adenosine stress CTP findings to predict mid-term major adverse cardiac events (MACE). In 240 patients with acute-onset chest pain, yet...... normal electrocardiograms and troponins, a clinically blinded adenosine stress CTP scan was performed in addition to conventional diagnostic evaluation. A reversible perfusion defect (PD) was found in 38 patients (16 %) and during a median follow-up of 19 months (range 12-22 months) 25 patients (10...

  18. Volume of myocardium perfused by coronary artery branches as estimated from 3D micro-CT images of rat hearts

    Science.gov (United States)

    Lund, Patricia E.; Naessens, Lauren C.; Seaman, Catherine A.; Reyes, Denise A.; Ritman, Erik L.

    2000-04-01

    Average myocardial perfusion is remarkably consistent throughout the heart wall under resting conditions and the velocity of blood flow is fairly reproducible from artery to artery. Based on these observations, and the fact that flow through an artery is the product of arterial cross-sectional area and blood flow velocity, we would expect the volume of myocardium perfused to be proportional to the cross-sectional area of the coronary artery perfusing that volume of myocardium. This relationship has been confirmed by others in pigs, dogs and humans. To test the body size-dependence of this relationship we used the hearts from rats, 3 through 25 weeks of age. The coronary arteries were infused with radiopaque microfil polymer and the hearts scanned in a micro- CT scanner. Using these 3D images we measured the volume of myocardium and the arterial cross-sectional area of the artery that perfused that volume of myocardium. The average constant of proportionality was found to be 0.15 +/- 0.08 cm3/mm2. Our data showed no statistically different estimates of the constant of proportionality in the rat hearts of different ages nor between the left and right coronary arteries. This constant is smaller than that observed in large animals and humans, but this difference is consistent with the body mass-dependence on metabolic rate.

  19. Prediction of cerebral hyperperfusion syndrome after carotid artery stenting by CT perfusion imaging with acetazolamide challenge

    Energy Technology Data Exchange (ETDEWEB)

    Yoshie, Tomohide; Ueda, Toshihiro; Takada, Tatsuro; Nogoshi, Shinji; Fukano, Takayuki [St. Marianna University Toyoko Hospital, Department of Strokology, Stroke Center, Kawasaki (Japan); Hasegawa, Yasuhiro [St. Marianna University School of Medicine, Department of Internal Medicine, Division of Neurology, Kawasaki (Japan)

    2016-03-15

    Cerebral hyperperfusion syndrome (HPS) is an uncommon but serious complication of carotid artery stenting (CAS). The purpose of this study was to investigate the efficacy of CT perfusion imaging (CTP) with acetazolamide challenge to identify patients at risk for HPS after CAS. We retrospectively analyzed 113 patients who underwent CTP with rest and acetazolamide challenge before CAS. CTP maps were assessed for absolute and relative cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and change of each parameter before and after acetazolamide challenge. Patients were divided into two groups according to the HPS after the CAS. Receiver-operating characteristic (ROC) curve analysis was performed to determine the most accurate CTP parameter for the prediction of HPS. Nine of 113 patients had HPS. There were significant differences for absolute and relative values of resting CBF (p = 0.001 and p = 0.026), resting MTT (p < 0.001 and p = 0.004), post-acetazolamide CBF (p < 0.001 and p = 0.001), post-acetazolamide MTT (p < 0.001 and p = 0.002), and %changes of CBF (p = 0.009) between the HPS and non-HPS groups. ROC curve analysis showed that the CTP parameters with the maximal area under the receiver-operating characteristic curve (AUC) for HPS was the absolute value of post-acetazolamide MTT (AUC 0.909) and the absolute value of resting MTT (AUC 0.896). Pretreatment CTP with acetazolamide challenge could identify patients at risk for HPS after CAS. Although the CTP parameter that most accurately identified patients at risk for HPS was the absolute value of post-acetazolamide MTT, resting MTT was sufficiently accurate. (orig.)

  20. Comparison of partial volume effects in arterial and venous contrast curves in CT brain perfusion imaging.

    Directory of Open Access Journals (Sweden)

    Alan J Riordan

    Full Text Available In brain CT perfusion (CTP, the arterial contrast bolus is scaled to have the same area under the curve (AUC as the venous outflow to correct for partial volume effects (PVE. This scaling is based on the assumption that large veins are unaffected by PVE. Measurement of the internal carotid artery (ICA, usually unaffected by PVE due to its large diameter, may avoid the need for partial volume correction. The aims of this work are to examine i the assumptions behind PVE correction and ii the potential of selecting the ICA obviating correction for PVE.The AUC of the ICA and sagittal sinus were measured in CTP datasets from 52 patients. The AUCs were determined by i using commercial CTP software based on a Gaussian curve-fitting to the time attenuation curve, and ii by simple integration of the time attenuation curve over a time interval. In addition, frames acquired up to 3 minutes after first bolus passage were used to examine the ratio of arterial and venous enhancement. The impact of selecting the ICA without PVE correction was illustrated by reporting cerebral blood volume (CBV measurements.In 49 of 52 patients, the AUC of the ICA was significantly larger than that of the sagittal sinus (p = 0.017. Measured after the first pass bolus, contrast enhancement remained 50% higher in the ICA just after the first pass bolus, and 30% higher 3 minutes later. CBV measurements were significantly lowered when the ICA was used without PVE correction.Contradicting the assumptions underlying PVE correction, contrast in the ICA was significantly higher than in the sagittal sinus, even 3 minutes after the first pass of the contrast bolus. PVE correction might lead to overestimation of CBV if the CBV is calculated using the AUC of the time attenuation curves.

  1. Head movement during CT brain perfusion acquisition of patients with suspected acute ischemic stroke

    International Nuclear Information System (INIS)

    Fahmi, F.; Beenen, L.F.M.; Streekstra, G.J.; Janssen, N.Y.; Jong, H.W. de; Riordan, A.; Roos, Y.B.; Majoie, C.B.; Bavel, E. van; Marquering, H.A.

    2013-01-01

    Objective: Computed Tomography Perfusion (CTP) is a promising tool to support treatment decision for acute ischemic stroke patients. However, head movement during acquisition may limit its applicability. Information of the extent of head motion is currently lacking. Our purpose is to qualitatively and quantitatively assess the extent of head movement during acquisition. Methods: From 103 consecutive patients admitted with suspicion of acute ischemic stroke, head movement in 220 CTP datasets was qualitatively categorized by experts as none, minimal, moderate, or severe. The movement was quantified using 3D registration of CTP volume data with non-contrast CT of the same patient; yielding 6 movement parameters for each time frame. The movement categorization was correlated with National Institutes of Health Stroke Scale (NIHSS) score and baseline characteristic using multinomial logistic regression and student's t-test respectively. Results: Moderate and severe head movement occurred in almost 25% (25/103) of all patients with acute ischemic stroke. The registration technique quantified head movement with mean rotation angle up to 3.6° and 14°, and mean translation up to 9.1 mm and 22.6 mm for datasets classified as moderate and severe respectively. The rotation was predominantly in the axial plane (yaw) and the main translation was in the scan direction. There was no statistically significant association between movement classification and NIHSS score and baseline characteristics. Conclusions: Moderate or severe head movement during CTP acquisition of acute stroke patients is quite common. The presented registration technique can be used to automatically quantify the movement during acquisition, which can assist identification of CTP datasets with excessive head movement

  2. Prediction of hemorrhagic transformation in acute ischemic stroke using permeability surface of CT perfusion

    International Nuclear Information System (INIS)

    Xiong Bing; Chen Weijian; Fufengli

    2012-01-01

    Objective: To investigate the value of permeability surface (PS) in predicting hemorrhagic transformation (HT) in acute ischernic stroke (AIS) using CT perfusion (CTP). Methods: The study included 31 consecutive patients who presented symptoms suggestive of an AIS for 3-9 h. All patients underwent CT examination (noncontrast CT, CTP). HT was determined by follow-up CT images. According to presence of HT, the AIS was divided into HT group (PS HT , 11 patients) and non-HT group (PS No-HT , 20 patients). PS, cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) on both sides of brains were measured.The relative PS (rPS), relative CBF (rCBF), relative CBV (rCBV) and relative MTT(rMTT) were obtained by calculating the ratio of the values of bilateral regions. The rPS between PS HT and PS No-HT was compared with an exact Wilcoxon signed-rank test. The rCBF, rCBV, rMTT and the PS of the ischemic side between PS HT and PS No-HT were compared with independent-sample t test. Meanwhile, Spearman rank correlation analysis was conducted to analyze the relationship between the CTP parameters and HT. Results: The PS value of ischemic side was (1.61 ±0.77) ml · min -1 · 100 g -1 for the PS HT group,and the value was (0.91 ± 0.49) ml · min -1 · 100 g -1 for the PS No-HT group. For the PS HT group, rPS, rCBF, rCBV, rMTT were 2.76 ±0.78, 0.32 ±0.18, 0.66 ±0.31, 2.67 ±0.71, and for the PS No-HT group, rPS, rCBF, rCBV, rMTT were 1.35 ±0.19, 0.50±0.21, 0.91 ±0.28, 2.62 ± 1.31. Compared with PS No-HT ,PS HT had higher rPS and PS value,and there were significant statistical differences (U=0.000, t=3.070, P<0.01). But rCBF and rCBV values were lower in the PS HT group compared to the PS No-HT group, and there were significant statistical differences (t rCBF =2.343, t rCBV =2.210, P<0.05). There was no significant statistical difference in rMTT between the two groups (t=0.118, P>0.05). Significant positive correlations were detected between the r

  3. Moyamoya disease and its effect on cerebral perfusion

    International Nuclear Information System (INIS)

    Turner, James K.

    2009-01-01

    Full text: Objective: Moyamoya disease is a rare progressive occlusive disorder which affects the vasculature of the brain. It results in stroke like systems and can cause death due to haemorrhage. This poster follows the clinical case of a 12 year old South Korean Female diagnosed with Moyamoya disease in January 2004 and the role nuclear medicine played in her management. Methods: The clinical history of the patient was examined closely, with all previous medical imaging reports and nursing entries collated. An extensive literature review of Moyamoya disease was then performed using a range of resources. Results: The patient's clinical work-up involved a range of medical imaging procedures the results of which did not provide a clear pathway for clinical management. A Nuclear Medicine Cerebral Perfusion Diamox Challenge study was subsequently performed providing a critical result. The results of this study were indicative of no change in vascular reserve both pre and post Diamox infusion. Ultimately the patient's physicians then delayed the need for anastmosis surgery, with alternate methods of treatment required. Conclusion: Overall this case highlights the need for functional imaging and the importance of drug therapies including Diamox in nuclear medicine procedures. This study ensured the patients quality of life was maintained and eliminated any risk involved in performing further surgery.

  4. Validation and absolute quantification of MR perfusion compared with CT perfusion in patients with unilateral cerebral arterial stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, Fang-Ying, E-mail: fychiou@hotmail.com [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China); Kao, Yi-Hsuan, E-mail: yhkao@ym.edu.tw [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China); Teng, Michael Mu Huo, E-mail: mhteng@gmail.com [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China); School of Medicine, National Yang-Ming University, Taipei City, Taiwan (China); Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan (China); Chung, Hsiao-Wen, E-mail: chung@cc.ee.ntu.edu.tw [Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan (China); Chang, Feng-Chi, E-mail: fcchang374@gmail.com [School of Medicine, National Yang-Ming University, Taipei City, Taiwan (China); Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan (China); Cho, I-Chieh, E-mail: jessie8030@yahoo.com.tw [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China); Chen, Wen-Chun, E-mail: sky7408695@hotmail.com [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China)

    2012-12-15

    Objective: The aim of the study was to assess absolute quantification of dynamic susceptibility contrast-enhanced magnetic resonance perfusion (MRP) comparing with computed tomography perfusion (CTP) in patients with unilateral stenosis. Materials and methods: We retrospectively post-processed MRP in 20 patients with unilateral occlusion or stenosis of >79% at the internal carotid artery or the middle cerebral artery (MCA). Absolute quantification of MRP was performed after applying the following techniques: cerebrospinal fluid removal, vessel removal, and automatic segmentation of brain to calculate the scaling factors to convert relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) values to absolute values. For comparison between MRP and CTP, we manually deposited regions of interest in bilateral MCA territories at the level containing the body of the lateral ventricle. Results: The correlation between MRP and CTP was best for mean transit time (MTT) (r = 0.83), followed by cerebral blood flow (CBF) (r = 0.52) and cerebral blood volume (CBV) (r = 0.43). There was no significant difference between CTP and MRP for CBV, CBF, and MTT on the lesion side, the contralateral side, the lesion-contralateral differences, or the lesion-to-contralateral ratios (P > 0.05). The mean differences between MRP and CTP were as follows: CBV −0.57 mL/100 g, CBF 2.50 mL/100 g/min, and MTT −0.90 s. Conclusion: Absolute quantification of MRP is possible. Using the proposed method, measured values of MRP and CTP had acceptable linear correlation and quantitative agreement.

  5. CT findings of orbital inflammatory diseases

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jang Min; Shin, Hyun Joon; Kim, Jung Hyuk; Suh, Won Hyuck [College of Medicine, Korea University, Seoul (Korea, Republic of)

    1991-09-15

    Twenty-nine patients with orbital inflammatory disease (OIDs) were retrospectively reviewed in order to analyze detailed CT findings which might aid in differentiating OIDs. This study comprised 18 pseudotumors, 5 thyroid ophthalmopathies, and 6 cases of orbital cellulitis. CT scans of the pseudotumors showed various findings such as exophthalmos, scleritis, myositis of the extraocular muscle (MOM), and bone lesion. Bone lesions of the pseudo tumors, which have been rarely reported, were present in 7 cases in our series. Bilateral exophthalmos, myositis, and retrobulbar fat deposition were readily detected by CT in thyroid ophthalmopathy, and, in addition, we found bone erosions involving the orbital apices in 2 cases. In orbital cellulitis, extraorbital soft tissue swelling and lateral displacement of the medial rectus muscle in cases with ethmoiditis were the most conspicuous features. In summary, because of the overlapping CT findings in OIDs, careful examination of CT findings regarding the mode of EOM involvement and the presence or absence of scleritis or sinusitis might help narrow down the differential diagnosis. A pseudotumor with bone lesions could be mistaken as a malignant lesion, and therefore it is necessary to correlate clinical features with CT findings for an accurate diagnosis.

  6. CT of acute gastrointestinal disease

    International Nuclear Information System (INIS)

    Wittenberg, J.

    1991-01-01

    The application of computerized tomography in gastrointestinal tract diseases are presented, including advantages in surgical belly that are: anatomic clarity, wide survey and rapid performance. (C.G.C.)

  7. Quantitative hepatic CT perfusion measurement: Comparison of Couinaud's hepatic segments with dual-source 128-slice CT

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xuan [The Department of Radiology, Peking Union Medical College Hospital, Dongcheng District, Beijing, 100730 (China); Xue, Hua-dan, E-mail: bjdanna95@hotmail.com [The Department of Radiology, Peking Union Medical College Hospital, Dongcheng District, Beijing, 100730 (China); Jin, Zheng-yu, E-mail: jin_zhengyu@163.com [The Department of Radiology, Peking Union Medical College Hospital, Dongcheng District, Beijing, 100730 (China); Su, Bai-yan; Li, Zhuo; Sun, Hao; Chen, Yu; Liu, Wei [The Department of Radiology, Peking Union Medical College Hospital, Dongcheng District, Beijing, 100730 (China)

    2013-02-15

    Purpose: To compare the quantitative liver computed tomography perfusion (CTP) differences among eight hepatic segments. Materials and methods: This retrospective study was based on 72 acquired upper abdomen CTP scans for detecting suspected pancreas tumor. Patients with primary or metastatic liver tumor, any focal liver lesions except simple cyst (<3 cm in diameter), history of liver operation or splenectomy, evidence of liver cirrhosis or invasion of portal vein were excluded. The final analysis included 50 patients (M:F = 21:29, mean age = 43.2 years, 15–76 years). Arterial liver perfusion (ALP), portal-venous perfusion (PVP), total hepatic perfusion (THP = ALP + PVP), and hepatic perfusion index (HPI) of each hepatic segment were calculated and compared by means of one-way analysis of variance (ANOVA) and the Bonferonni correction method. Results: Compared to hepatic segments 5, 6, 7 and 8, segments 2 and 3 showed a tendency of higher ALPs, lower PVPs, and higher HPIs, most of which were statistically significant (p < 0.05). Hepatic segments 1 and 4 had higher mean values of ALP and HPI and lower mean values of PVP than segments 5, 6, 7 and 8 as well, although no significant differences were detected except for ALP and HPI for liver segments 1 and 7 (p = 0.001 and 0.035 respectively), and ALP for liver segments 1 and 5 (p = 0.039). Higher ALP and HPI were showed in hepatic segment 3 compared to segment 4 (p = 0.000 and 0.000 respectively). No significant differences were found for THP among eight segments. Conclusions: Intra-hepatic perfusion differences exist in normal hepatic parenchyma especially between lateral sector (segments 2 and 3) and right lobe (segments 5, 6, 7 and 8). This might have potential clinical significance in liver-perfusion-related protocol design and result analysis.

  8. Regional blood perfusion in childhood partial seizure using N-isopropyl-p-[I-123]iodoamphetamine and single photon emission CT

    International Nuclear Information System (INIS)

    Michihiro, Narumi; Kurosawa, Yumiko; Hibio, Shuichi; Ishihara, Hiroaki; Ariizumi, Motomizu

    1989-01-01

    Single photon emission CT (SPECT) with N-isopropyl-p-[I-123]iodoamphetamine was performed in 20 pediatric patients with partial seizure to examine regional blood perfusion. In detecting location of abnormality, SPECT and EEG were concordant in 13 patients (65%) and discordant in 4 patients (20%). In 7 patients undergoing SPECT one to 4 years after seizure onset, decreased blood perfusion corresponded to focal abnormality on EEG. In other 9 patiets in whom SPECT was performed within one year, however, location of abnormality on SPECT did not necessarily concur with that on EEG. These findings suggest that brain lesions are not focal but extensive at the early stage of partial seizure and that they are becoming focal with the mature of the central nervous system. (Namekawa, K)

  9. Contrast adaptive total p-norm variation minimization approach to CT reconstruction for artifact reduction in reduced-view brain perfusion CT

    Science.gov (United States)

    Kim, Chang-Won; Kim, Jong-Hyo

    2011-03-01

    Perfusion CT (PCT) examinations are getting more frequently used for diagnosis of acute brain diseases such as hemorrhage and infarction, because the functional map images it produces such as regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), and mean transit time (MTT) may provide critical information in the emergency work-up of patient care. However, a typical PCT scans the same slices several tens of times after injection of contrast agent, which leads to much increased radiation dose and is inevitability of growing concern for radiation-induced cancer risk. Reducing the number of views in projection in combination of TV minimization reconstruction technique is being regarded as an option for radiation reduction. However, reconstruction artifacts due to insufficient number of X-ray projections become problematic especially when high contrast enhancement signals are present or patient's motion occurred. In this study, we present a novel reconstruction technique using contrast-adaptive TpV minimization that can reduce reconstruction artifacts effectively by using different p-norms in high contrast and low contrast objects. In the proposed method, high contrast components are first reconstructed using thresholded projection data and low p-norm total variation to reflect sparseness in both projection and reconstruction spaces. Next, projection data are modified to contain only low contrast objects by creating projection data of reconstructed high contrast components and subtracting them from original projection data. Then, the low contrast projection data are reconstructed by using relatively high p-norm TV minimization technique, and are combined with the reconstructed high contrast component images to produce final reconstructed images. The proposed algorithm was applied to numerical phantom and a clinical data set of brain PCT exam, and the resultant images were compared with those using filtered back projection (FBP) and conventional TV

  10. Lung perfusion characteristics in pulmonary arterial hypertension (PAH) and peripheral forms of chronic thromboembolic pulmonary hypertension (pCTEPH): Dual-energy CT experience in 31 patients.

    Science.gov (United States)

    Giordano, Jessica; Khung, Suonita; Duhamel, Alain; Hossein-Foucher, Claude; Bellèvre, Dimitri; Lamblin, Nicolas; Remy, Jacques; Remy-Jardin, Martine

    2017-04-01

    To compare lung perfusion in PAH and pCTEPH on dual-energy CT (DECT) examinations. Thirty-one patients with PAH (group 1; n = 19) and pCTEPH (group 2; n = 12) underwent a dual-energy chest CTA with reconstruction of diagnostic and perfusion images. Perfusion alterations were analysed at a segmental level. V/Q scintigraphy was available in 22 patients (group 1: 13/19; group 2: 9/12). CT perfusion was abnormal in 52.6 % of group 1 patients and in 100 % of group 2 patients (p = 0.0051). The patterns of perfusion alteration significantly differed between the two groups (p perfusion showed patchy defects; (2) in group 2, the most frequent abnormalities consisted of patchy (58.5 %) and PE-type (37.5 %) defects. Paired comparison of CT perfusion and scintigraphy showed concordant findings in 76.9 % of group 1 (10/13) and 100 % of group 2 (9/9) patients, with a predominant or an exclusive patchy pattern in group 1 and a mixed pattern of abnormalities in group 2. Lung perfusion alterations at DECT are less frequent and more homogeneous in PAH than in pCTEPH, with a high level of concordant findings with V/Q scintigraphy. • Depiction of chronic pulmonary embolism exclusively located on peripheral arteries is difficult. • The main differential diagnosis of pCTEPH is PAH. • The pattern of DECT perfusion changes can help differentiate PAH and pCETPH. • In PAH, almost all segments with abnormal perfusion showed patchy defects. • In pCTEPH, patchy and PE-type defects were the most frequent abnormalities.

  11. Incidental apical disease at CT scanning

    International Nuclear Information System (INIS)

    McLoud, T.C.; Satoh, K.; Shepard, J.O.; Moore, E.H.; Kosiuk, J.P.

    1990-01-01

    Apical caps are commonly noted on standard radiographs. This paper determines how often abnormalities in the extreme apex of the lung could be identified on CT scans obtained for other reasons. A total of 158 consecutive CT scans were reviewed prospectively. Excluded were patients with obvious upper lobe pleural or parenchymal disease. Apical abnormalities were identified in 74 (46.8%) of the 158 cases. The prevalence increased with age (19% in the 8-39-year age group and 82% in patients older than 80 years). Opacities were unilateral in 44.5% and bilateral in 55.5%. The most common abnormality was linear opacities (95%)

  12. Detection of pulmonary embolism with combined ventilation-perfusion SPECT and low-dose CT: head-to-head comparison with multidetector CT angiography

    DEFF Research Database (Denmark)

    Gutte, Henrik; Mortensen, Jann; Jensen, Claus Verner

    2009-01-01

    The diagnosis of pulmonary embolism (PE) is usually established by a combination of clinical assessment, D-dimer testing, and imaging with either pulmonary ventilation-perfusion (V/Q) scintigraphy or pulmonary multidetector CT (MDCT) angiography. Both V/Q SPECT and MDCT angiography seem to have...... high diagnostic accuracy. However, only limited data directly comparing these 2 modalities are available. Hybrid gamma-camera/MDCT systems have been introduced and allow simultaneous 3-dimensional lung V/Q SPECT and MDCT angiography, suitable for diagnosing PE. The aim of our study was to compare...

  13. Diagnostic performance of whole brain volume perfusion CT in intra-axial brain tumors: Preoperative classification accuracy and histopathologic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Xyda, Argyro, E-mail: argyro.xyda@med.uni-goettingen.de [Department of Neuroradiology, Georg-August University, University Hospital of Goettingen, Robert-Koch Strasse 40, 37075 Goettingen (Germany); Department of Radialogy, University Hospital of Heraklion, Voutes, 71110 Heraklion, Crete (Greece); Haberland, Ulrike, E-mail: ulrike.haberland@siemens.com [Siemens AG Healthcare Sector, Computed Tomography, Siemensstr. 1, 91301 Forchheim (Germany); Klotz, Ernst, E-mail: ernst.klotz@siemens.com [Siemens AG Healthcare Sector, Computed Tomography, Siemensstr. 1, 91301 Forchheim (Germany); Jung, Klaus, E-mail: kjung1@uni-goettingen.de [Department of Medical Statistics, Georg-August University, Humboldtallee 32, 37073 Goettingen (Germany); Bock, Hans Christoph, E-mail: cbock@gmx.de [Department of Neurosurgery, Johannes Gutenberg University Hospital of Mainz, Langenbeckstraße 1, 55101 Mainz (Germany); Schramm, Ramona, E-mail: ramona.schramm@med.uni-goettingen.de [Department of Neuroradiology, Georg-August University, University Hospital of Goettingen, Robert-Koch Strasse 40, 37075 Goettingen (Germany); Knauth, Michael, E-mail: michael.knauth@med.uni-goettingen.de [Department of Neuroradiology, Georg-August University, University Hospital of Goettingen, Robert-Koch Strasse 40, 37075 Goettingen (Germany); Schramm, Peter, E-mail: p.schramm@med.uni-goettingen.de [Department of Neuroradiology, Georg-August University, University Hospital of Goettingen, Robert-Koch Strasse 40, 37075 Goettingen (Germany)

    2012-12-15

    Background: To evaluate the preoperative diagnostic power and classification accuracy of perfusion parameters derived from whole brain volume perfusion CT (VPCT) in patients with cerebral tumors. Methods: Sixty-three patients (31 male, 32 female; mean age 55.6 ± 13.9 years), with MRI findings suspected of cerebral lesions, underwent VPCT. Two readers independently evaluated VPCT data. Volumes of interest (VOIs) were marked circumscript around the tumor according to maximum intensity projection volumes, and then mapped automatically onto the cerebral blood volume (CBV), flow (CBF) and permeability Ktrans perfusion datasets. A second VOI was placed in the contra lateral cortex, as control. Correlations among perfusion values, tumor grade, cerebral hemisphere and VOIs were evaluated. Moreover, the diagnostic power of VPCT parameters, by means of positive and negative predictive value, was analyzed. Results: Our cohort included 32 high-grade gliomas WHO III/IV, 18 low-grade I/II, 6 primary cerebral lymphomas, 4 metastases and 3 tumor-like lesions. Ktrans demonstrated the highest sensitivity, specificity and positive predictive value, with a cut-off point of 2.21 mL/100 mL/min, for both the comparisons between high-grade versus low-grade and low-grade versus primary cerebral lymphomas. However, for the differentiation between high-grade and primary cerebral lymphomas, CBF and CBV proved to have 100% specificity and 100% positive predictive value, identifying preoperatively all the histopathologically proven high-grade gliomas. Conclusion: Volumetric perfusion data enable the hemodynamic assessment of the entire tumor extent and provide a method of preoperative differentiation among intra-axial cerebral tumors with promising diagnostic accuracy.

  14. Diagnostic performance of whole brain volume perfusion CT in intra-axial brain tumors: Preoperative classification accuracy and histopathologic correlation

    International Nuclear Information System (INIS)

    Xyda, Argyro; Haberland, Ulrike; Klotz, Ernst; Jung, Klaus; Bock, Hans Christoph; Schramm, Ramona; Knauth, Michael; Schramm, Peter

    2012-01-01

    Background: To evaluate the preoperative diagnostic power and classification accuracy of perfusion parameters derived from whole brain volume perfusion CT (VPCT) in patients with cerebral tumors. Methods: Sixty-three patients (31 male, 32 female; mean age 55.6 ± 13.9 years), with MRI findings suspected of cerebral lesions, underwent VPCT. Two readers independently evaluated VPCT data. Volumes of interest (VOIs) were marked circumscript around the tumor according to maximum intensity projection volumes, and then mapped automatically onto the cerebral blood volume (CBV), flow (CBF) and permeability Ktrans perfusion datasets. A second VOI was placed in the contra lateral cortex, as control. Correlations among perfusion values, tumor grade, cerebral hemisphere and VOIs were evaluated. Moreover, the diagnostic power of VPCT parameters, by means of positive and negative predictive value, was analyzed. Results: Our cohort included 32 high-grade gliomas WHO III/IV, 18 low-grade I/II, 6 primary cerebral lymphomas, 4 metastases and 3 tumor-like lesions. Ktrans demonstrated the highest sensitivity, specificity and positive predictive value, with a cut-off point of 2.21 mL/100 mL/min, for both the comparisons between high-grade versus low-grade and low-grade versus primary cerebral lymphomas. However, for the differentiation between high-grade and primary cerebral lymphomas, CBF and CBV proved to have 100% specificity and 100% positive predictive value, identifying preoperatively all the histopathologically proven high-grade gliomas. Conclusion: Volumetric perfusion data enable the hemodynamic assessment of the entire tumor extent and provide a method of preoperative differentiation among intra-axial cerebral tumors with promising diagnostic accuracy.

  15. Comparison of microvascular perfusion evaluation among IVIM-DWI, CT perfusion imaging and histological microvessel density in rabbit liver VX2 tumors.

    Science.gov (United States)

    Li, Jing-Lei; Ye, Wei-Tao; Liu, Zai-Yi; Yan, Li-Fen; Luo, Wei; Cao, Xi-Ming; Liang, Changhong

    2018-02-01

    To explore microcirculation features with intravoxel incoherent motion (IVIM) and to compare IVIM with CT perfusion imaging (CTPI) and microvessel density (MVD). Hepatic CTPI and IVIM were performed in 16 rabbit liver VX2 tumor models. Hepatic arterial perfusion (HAP), hepatic arterial perfusion index (HPI), Blood flow (BF), and blood volume (BV) from CTPI were measured. Apparent diffusion coefficient (ADC), true diffusion coefficient (D), perfusion fraction (f), and pseudo-diffusion coefficient (D*) from IVIM were measured. MVD was counted with CD34 stain. The microcirculation features with IVIM were compared with CTPI parameters and MVD