scholarly journals CT Perfusion Imaging Improves Infarct Conspicuity in Hyperacute Stroke

Stroke ◽  
2001 ◽  
Vol 32 (suppl_1) ◽  
pp. 325-325
Author(s):  
Peter Bove ◽  
Michael H Lev ◽  
Dmetri Berdichevsky ◽  
Gordon J Harris ◽  
Nathaniel M Alpert ◽  
...  
Keyword(s):  
Ct Angiography ◽  
Blood Volume ◽  
Gray Matter ◽  
Cerebral Blood Volume ◽  
Ct Perfusion ◽  
Blood Pool ◽  
Hyperacute Stroke ◽  
Tissue Edema ◽  
The Mean ◽  
Volume Ct

51 Purpose: To compare infarct conspicuity and image quality of noncontrast CT (NCCT), CT perfusion (CTP), and CT subtraction cerebral blood volume (CT-CBV) images of patients with hyperacute stroke. Background: NCCT is typically the first imaging test obtained in the evaluation of acute stroke. Whole brain CTP imaging is performed, simultaneously with CT angiography, during the steady state administration of IV contrast. Subtraction of coregistered NCCT images from the CTP images yields maps of perfused blood volume (CT-CBV). Ischemic areas on each of the NCCT, CTP, and CT-CBV images appear as hypodense, low attenuation regions. Materials and Methods: We reviewed the images of 20 consecutive patients with MCA stem occlusion who underwent intra-arterial thrombolysis within 6 hours of stroke onset. All had NCCT and CT angiography with CTP imaging prior to thrombolysis. Subtraction CT-CBV maps were created and analyzed using proprietary software (IMIPS, Inc). For each of the NCCT, CTP, and CT-CBV images, infarct conspicuity was defined by dividing the mean attenuation difference between normal and maximally hypodense gray matter by the mean normal gray matter attenuation. Contrast-to-noise ratio (CNR) was defined by dividing the same numerator by the standard deviation of the normal gray matter attenuation values. Statistical analysis was by ANOVA and students t-test. Results: Overall infarct conspicuity was 0.11 for the NCCT, 0.22 for the CTP, and 0.98 for the CT-CBV images (p<0.003 for all maps). Mean CNR was 0.95 for the NCCT, 1.94 for the CTP, and 1.12 for the CT-CBV images (p<0.01, for the CTP maps only). Conclusions: CT perfusion and CT-CBV subtraction imaging improve infarct conspicuity over that of NCCT in patients with hyperacute stroke. True reduction in blood pool (as reflected by CT-CBV), rather than increase in tissue edema (as reflected by NCCT), may explain much of the improved infarct delineation in CTP imaging. Because CNR is greater for CTP than for subtraction images, concurrent review of NCCT, CTP, and CT-CBV images may be indicated for optimal CT assessment of hyperacute MCA stroke.

scholarly journals Cerebral CT Perfusion in Acute Stroke: The Effect of Lowering the Tube Load and Sampling Rate on the Reproducibility of Parametric Maps

Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1121
Author(s):  
Georgios S. Ioannidis ◽  
Søren Christensen ◽  
Katerina Nikiforaki ◽  
Eleftherios Trivizakis ◽  
Kostas Perisinakis ◽  
...  
Keyword(s):  
Cerebral Blood Volume ◽  
Ct Perfusion ◽  
Sampling Rate ◽  
Volumetric Analysis ◽  
Sampling Interval ◽  
Diagnostic Efficiency ◽  
Temporal Sampling ◽  
Sampling Intervals ◽  
The Mean ◽  
Parametric Maps

The aim of this study was to define lower dose parameters (tube load and temporal sampling) for CT perfusion that still preserve the diagnostic efficiency of the derived parametric maps. Ninety stroke CT examinations from four clinical sites with 1 s temporal sampling and a range of tube loads (mAs) (100–180) were studied. Realistic CT noise was retrospectively added to simulate a CT perfusion protocol, with a maximum reduction of 40% tube load (mAs) combined with increased sampling intervals (up to 3 s). Perfusion maps from the original and simulated protocols were compared by: (a) similarity using a voxel-wise Pearson’s correlation coefficient r with in-house software; (b) volumetric analysis of the infarcted and hypoperfused volumes using commercial software. Pearson’s r values varied for the different perfusion metrics from 0.1 to 0.85. The mean slope of increase and cerebral blood volume present the highest r values, remaining consistently above 0.7 for all protocol versions with 2 s sampling interval. Reduction of the sampling rate from 2 s to 1 s had only modest impacts on a TMAX volume of 0.4 mL (IQR −1–3) (p = 0.04) and core volume of −1.1 mL (IQR −4–0) (p < 0.001), indicating dose savings of 50%, with no practical loss of diagnostic accuracy. The lowest possible dose protocol was 2 s temporal sampling and a tube load of 100 mAs.

Hyperacute Stroke: Simultaneous Measurement of Relative Cerebral Blood Volume, Relative Cerebral Blood Flow, and Mean Tissue Transit Time

Radiology ◽  
1999 ◽  
Vol 210 (2) ◽  
pp. 519-527 ◽  
Author(s):  
A. Gregory Sorensen ◽  
William A. Copen ◽  
Leif Østergaard ◽  
Ferdinando S. Buonanno ◽  
R. Gilberto Gonzalez ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Blood Volume ◽  
Transit Time ◽  
Simultaneous Measurement ◽  
Cerebral Blood Volume ◽  
Hyperacute Stroke ◽  
Relative Cerebral Blood Volume

Abstract 3268: Ct Perfusion As A Tool To Predict The Risk Of Hemorrhagic Transformation In Ischemic Stroke Treated With Tissue Plasminogen Activator: A Single Center Experience.

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Tareq Kass-Hout ◽  
Maxim Mokin ◽  
Omar Kass-Hout ◽  
Emad Nourollahzadeh ◽  
David Wack ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Stroke ◽  
Brain Tissue ◽  
Cerebral Blood Volume ◽  
Ct Perfusion ◽  
Intravenous Thrombolysis ◽  
Hemorrhagic Transformation ◽  
Stroke Therapy ◽  
Two Phase ◽  
The Mean

Objective: To use the Computed Tomography Perfusion (CTP) parameters at the time of hospital admission, including Cerebral Blood Volume (CBV) and Permeability Surface area product (PS), to identify patients with higher risk to develop hemorrhagic transformation in the setting of acute stroke therapy with intravenous thrombolysis. Methods: Retrospective study that compared admission CTP variables between patients with Hemorrhagic Transformation (HT) acute stroke and those with no hemorrhagic transformation. Both groups received standard of care intravenous thrombolysis with tPA. Twenty patients presented to our stroke center between the years 2007 - 2011 within 3 hours after stroke symptoms onset. All patients underwent two-phase 320 slice CTP which creates CBV and PS measurements. Patients were divided into two groups according to whether or not they had HT on a follow up CT head without contrast, done within 36 hours of the thrombolysis therapy. Clinical, demographic and CTP variables were compared between the HT and non-HT groups using logistic regression analyses. Results: HT developed in 8 (40%) patients. Patients with HT had lower ASPECT score ( P =.03), higher NIHSS on admission ( P= .01) and worse outcome ( P= .04) compared to patients who did not develop HT. Baseline blood flow defects were comparable between the two groups. The mean PS for the HT group was 0.53 mL/min/100g brain tissue, which was significantly higher than that for the non-HT group of 0.04 mL/min/100g brain tissue ( P <.0001). The mean area under the curve was 0.92 (95% CI). The PS threshold of 0.26 mL/min/100g brain tissue had a sensitivity of 80% and a specificity of 92% for detecting patients with high risk of hemorrhagic transformation after intravenous thrombolysis. Conclusions: Admission CTP measurements might be useful to predict patients who are at higher risk to develop hemorrhagic transformation after acute ischemic stroke therapy.

scholarly journals Low Cerebral Blood Volume Is Predictive of Diffusion Restriction Only in Hyperacute Stroke

Stroke ◽  
2010 ◽  
Vol 41 (12) ◽  
pp. 2795-2800 ◽  
Author(s):  
Michael Knash ◽  
Adrian Tsang ◽  
Bilal Hameed ◽  
Monica Saini ◽  
Thomas Jeerakathil ◽  
...  
Keyword(s):  
Blood Volume ◽  
Cerebral Blood Volume ◽  
Diffusion Restriction ◽  
Hyperacute Stroke

scholarly journals CT Perfusion and Delayed Cerebral Ischemia in Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis

2013 ◽  
Vol 34 (2) ◽  
pp. 200-207 ◽  
Author(s):  
Charlotte H P Cremers ◽  
Irene C van der Schaaf ◽  
Emerens Wensink ◽  
Jacoba P Greving ◽  
Gabriel J E Rinkel ◽  
...  
Keyword(s):  
Systematic Review ◽  
Subarachnoid Hemorrhage ◽  
Cerebral Ischemia ◽  
Blood Volume ◽  
Cerebral Blood Volume ◽  
Ct Perfusion ◽  
Aneurysmal Subarachnoid Hemorrhage ◽  
Mean Transit Time ◽  
Delayed Cerebral Ischemia ◽  
Mean Difference

Delayed cerebral ischemia (DCI) is at presentation a diagnosis per exclusionem, and can only be confirmed with follow-up imaging. For treatment of DCI a diagnostic tool is needed. We performed a systematic review to evaluate the value of CT perfusion (CTP) in the prediction and diagnosis of DCI. We searched PubMed, Embase, and Cochrane databases to identify studies on the relationship between CTP and DCI. Eleven studies totaling 570 patients were included. On admission, cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and time-to-peak (TTP) did not differ between patients who did and did not develop DCI. In the DCI time-window (4 to 14 days after subarachnoid hemorrhage (SAH)), DCI was associated with a decreased CBF (pooled mean difference −11.9 mL/100 g per minute (95% confidence interval (CI): −15.2 to −8.6)) and an increased MTT (pooled mean difference 1.5 seconds (0.9–2.2)). Cerebral blood volume did not differ and TTP was rarely reported. Perfusion thresholds reported in studies were comparable, although the corresponding test characteristics were moderate and differed between studies. We conclude that CTP can be used in the diagnosis but not in the prediction of DCI. A need exists to standardize the method for measuring perfusion with CTP after SAH, and optimize and validate perfusion thresholds.

scholarly journals In Acute Stroke, Can CT Perfusion-Derived Cerebral Blood Volume Maps Substitute for Diffusion-Weighted Imaging in Identifying the Ischemic Core?

PLoS ONE ◽  
2015 ◽  
Vol 10 (7) ◽  
pp. e0133566 ◽  
Author(s):  
William A. Copen ◽  
Livia T. Morais ◽  
Ona Wu ◽  
Lee H. Schwamm ◽  
Pamela W. Schaefer ◽  
...  
Keyword(s):  
Acute Stroke ◽  
Blood Volume ◽  
Diffusion Weighted Imaging ◽  
Cerebral Blood Volume ◽  
Ct Perfusion ◽  
Diffusion Weighted ◽  
Ischemic Core

Whole-Brain Volume CT Angiography can Effectively Detect Early Ischemic Cerebrovascular Diseases

2021 ◽  
Vol 17 ◽  
Author(s):  
Shi-Feng Xiang ◽  
Jun-Tao Li ◽  
Su-Jun Yang ◽  
Fang-Fang Ding ◽  
Wei-Wei Wang ◽  
...  
Keyword(s):  
Ct Scan ◽  
Ct Angiography ◽  
Brain Volume ◽  
Ct Perfusion ◽  
Cerebrovascular Diseases ◽  
Whole Brain ◽  
Ischemic Cerebrovascular Diseases ◽  
Vascular Stenosis ◽  
Cerebral Ischemic ◽  
Volume Ct

Objective: To investigate the role of whole-brain volume computed tomography (CT) perfusion in assessing early ischemic cerebrovascular diseases. Materials and Methods: Seventy-two patients with early ischemic cerebrovascular diseases who had undergone routine CT scan and 320-row volume CT whole-brain perfusion imaging within 8 h after admission were retrospectively enrolled in this one-center case-sectional study. The perfusion parameters of cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and dynamic CT angiogram (4D-CTA) were obtained and analyzed. Results: Among 72 patients, 29 cases with 37 cerebral ischemic lesions were found in plain CT scan, whereas 51 cases with 76 lesions were found in whole-brain CT perfusion, with 30.6% more patients being detected. The CBF value was significantly lower in the abnormal than normal corresponding perfusion area in the healthy hemisphere (P<0.05), while the MTT and TTP values were significantly higher in the abnormal than the normal corresponding area (P<0.05). 4D-CTA image suggested that 59 cases had different degrees of stenosis or occlusion, including 11 mild, 18 moderate, 21 severe, and 9 occlusive cases. Four-D-CTA imaging could detect significantly (P<0.05) more patients with abnormal perfusion in severe cerebral vascular stenosis or occlusion than those with no, mild or moderate stenosis (93.33% vs. 16.67%) (P<0.05). The stenosis of intracranial and carotid arteries was positively correlated with MTT and TTP values (P<0.05). Conclusion: Whole-brain volume CT angiography can comprehensively display early cerebral ischemic lesions, cerebral blood perfusion status, and cerebral vascular stenosis, providing valuable information for early detection of ischemic cerebral diseases and appropriate treatment planning.

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