Dynamically grading cerebral collateral circulation using 3D multi-inversion time arterial spin labeling in ischemic...

Area of Science:

• Neurology
• Medical Imaging
• Radiology

Background:

• Collateral circulation is crucial for acute ischemic stroke (AIS) outcomes.
• Assessing collateral status non-invasively is essential for guiding treatment decisions.
• Digital subtraction angiography (DSA) is an invasive standard for evaluating collateral flow.

Purpose of the Study:

• To introduce and evaluate a novel non-invasive imaging method, 3D multi-inversion time arterial spin labeling (3D mTI-ASL), for grading collateral circulation in AIS patients.
• To compare the effectiveness of 3D mTI-ASL with DSA in assessing collateral status.
• To determine the reliability and potential clinical utility of 3D mTI-ASL in acute stroke management.

Main Methods:

• Retrospective analysis of 28 AIS patients with internal carotid artery or middle cerebral artery occlusion.
• Comparison of collateral grading between 3D mTI-ASL and DSA performed before endovascular treatment.
• Development of a post-processing pipeline for collateral grading using 16 perfusion-weighted images from 3D mTI-ASL.

Main Results:

• Strong interobserver agreement for both DSA (κ=0.856) and 3D mTI-ASL (κ=0.849).
• Moderate consistency in collateral grading between 3D mTI-ASL and DSA (κ=0.568), improving significantly when dichotomized into poor and good collateral groups (κ=0.781).
• Good collaterals (Grades 3-4) were associated with lower admission NIH Stroke Scale scores compared to poor collaterals.

Conclusions:

• 3D mTI-ASL is a promising, reliable, non-invasive method for assessing collateral circulation in AIS.
• 3D mTI-ASL can simulate DSA-derived collateral grading.
• This technique may serve as a valuable complementary tool in acute stroke management decision-making.