Related Experiment Video
Updated: May 28, 2026
Brain Infarct Segmentation and Registration on MRI or CT for Lesion-symptom Mapping
Published on: September 25, 2019
Diagnostic performance of PWI/DWI MRI parameters in discriminating hyperacute versus acute ischaemic stroke: finding
E Roldan-Valadez1, O Gonzalez-Gutierrez, M Martinez-Lopez
1Magnetic Resonance Unit, Medica Sur Hospital & Clinic Foundation, Mexico City, Mexico. ernest.roldan@usa.net
Aim:
To determine the accuracy of the perfusion/diffusion-weighted imaging (PWI/DWI) parameters [time to peak (TTP), mean time to peak (MTT), relative cerebral blood volume (rCBV), and relative cerebral blood flow (rCBF) maps]; in the evaluation of acute versus hyperacute ischaemic stroke.
Materials And Methods:
Fifty-five patients with symptomatic hyperacute (first 6h) or acute (7-24h) ischaemic stroke underwent diffusion and perfusion evaluation. Statistical analysis included Student's t-test, receiver operating characteristics (ROC) analysis of apparent diffusion coefficient (ADC), TTP, MTT, CBV, and CBF; correlation, linear, and logistic regression analysis.
Results:
Area under receiver operating characteristics (AUROC) analysis identified the ADC cut-off value 385×10(-6)mm(2)/s, MTT at 109.5%, TTP at 3.05s, CBV at 129%, and CBF at 98.5% (the record of the time of onset was considered the reference standard). The best performance corresponded to TTP, which showed a sensitivity of 0.94 and specificity of 0.88 (p<0.001).
Conclusions:
Based on the present findings, hyperacute penumbra is reliably defined with a TTP >3s with no visible changes in diffusion. ADC, rCBF, and rCBV are not useful for discriminating between acute and hyperacute ischaemic stroke.
Insights
Time to peak (TTP) imaging accurately distinguishes hyperacute from acute ischemic stroke within 6 hours. Other perfusion/diffusion parameters like ADC, rCBF, and rCBV were not useful for this differentiation.
Area of Science:
- Neuroimaging
- Radiology
- Cerebrovascular Disease
Background:
- Acute ischemic stroke requires timely and accurate diagnosis for effective treatment.
- Differentiating hyperacute from acute ischemic stroke is crucial for selecting appropriate therapeutic interventions.
- Perfusion/diffusion-weighted imaging (PWI/DWI) parameters are being investigated for their diagnostic utility.
Purpose of the Study:
- To evaluate the accuracy of PWI/DWI parameters in distinguishing between hyperacute (0-6 hours) and acute (7-24 hours) ischemic stroke.
- To identify the most reliable imaging marker for early ischemic stroke characterization.
Main Methods:
- Fifty-five patients with symptomatic ischemic stroke underwent PWI/DWI.
- Statistical analyses included t-tests, ROC analysis for ADC, TTP, MTT, CBV, and CBF, and regression analyses.
- The time of stroke onset was used as the reference standard.
Main Results:
- Receiver operating characteristic (ROC) analysis identified optimal cut-off values for ADC, MTT, TTP, CBV, and CBF.
- Time to peak (TTP) demonstrated the highest diagnostic performance with a sensitivity of 0.94 and specificity of 0.88 (p<0.001).
- ADC, relative cerebral blood flow (rCBF), and relative cerebral blood volume (rCBV) were not effective in discriminating between stroke phases.
Conclusions:
- Time to peak (TTP) >3 seconds reliably defines the hyperacute penumbra in ischemic stroke when diffusion imaging shows no changes.
- TTP is a valuable parameter for differentiating hyperacute from acute ischemic stroke.
- ADC, rCBF, and rCBV are not recommended for distinguishing between these early stroke phases.
