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Updated: Jun 21, 2026
10:25
Brain Infarct Segmentation and Registration on MRI or CT for Lesion-symptom Mapping
Published on: September 25, 2019
Geography, structure, and evolution of diffusion and perfusion lesions in Diffusion and perfusion imaging Evaluation
Jean-Marc Olivot1, Michael Mlynash, Vincent N Thijs
1Department of Neurology, Neurological Sciences and the Stanford Stroke Center, Stanford University Medical Center, Stanford, CA, USA. jmolivot@stanford.edu
Stroke
|August 15, 2009
Summary
Before thrombolysis, Type 2 lesion geography is common and linked to diffusion-weighted imaging (DWI) reversal. After treatment, Type 2 geography and multiple lesions indicate reperfusion.
Area of Science:
- Neuroradiology
- Stroke Imaging
- Cerebrovascular Diseases
Background:
- Acute ischemic stroke assessment relies on MRI diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI).
- Understanding the spatial relationship between early imaging findings and final infarcts is crucial for treatment decisions.
Purpose of the Study:
- To investigate the spatial relationships between final infarcts and early DWI/PWI lesions.
- To analyze these relationships before and after intravenous thrombolysis in acute ischemic stroke patients.
Main Methods:
- Coregistration of baseline and follow-up DWI, PWI, and FLAIR MRI scans from 32 patients.
- Classification of lesion geography (Type 1: >50% overlap, Type 2: <=50% overlap) based on DWI and PWI.
- Assessment of lesion structure (single vs. multiple) and lesion reversal.
Main Results:
- Type 2 geography was predominant at baseline (72%) and early follow-up (88%).
- Single lesion structure with Type 1 geography was infrequent.
- DWI reversal was more common with Type 2 geography; reperfusion was associated with Type 2 geography and multiple lesions post-thrombolysis.
Conclusions:
- Type 2 geography is prevalent before thrombolysis and predicts DWI reversal.
- Post-thrombolysis, Type 2 geography and multiple lesion structures are indicators of reperfusion.
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