Alberta Stroke Program Early CT Score and collateral status predict target mismatch in large vessel occlusion with...

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Alberta Stroke Program Early CT Score (ASPECTS) and collateral score (CS) are established imaging metrics for acute ischemic stroke (AIS) with large vessel occlusion (LVO).
• Evaluating these metrics in delayed time windows is crucial for optimizing treatment strategies.

Purpose of the Study:

• To assess the predictive capability of combining ASPECTS and CS for identifying CT perfusion (CTP) target mismatch in delayed time windows for LVO-AIS patients.
• To determine if combined imaging scores improve the detection of penumbral tissue.

Main Methods:

• 164 LVO-AIS patients underwent non-contrast CT (NCCT) for ASPECTS and single-phase CT angiography (sCTA) for CS assessment.
• Target mismatch was defined using CTP criteria: core volume ≤70 mL, mismatch ratio ≥1.8, and absolute mismatch volume ≥15 mL.
• Statistical analyses included Spearman correlation and receiver operating characteristic (ROC) curve analyses.

Main Results:

• A strong negative correlation was found between NCCT ASPECTS and CTP core volume (r_s=-0.756, p<0.0001).
• A moderate negative correlation was observed between sCTA-CS and CTP core volume (r_s=-0.450, p<0.0001).
• The combined ASPECTS and CS score demonstrated superior prediction of target mismatch (AUC=0.882) compared to individual scores.

Conclusions:

• NCCT ASPECTS strongly correlates with CTP core volumes in delayed LVO-AIS.
• Integrating NCCT ASPECTS and sCTA-CS significantly enhances the prediction of CTP target mismatch.
• The combination of NCCT ASPECTS and sCTA-CS offers a valuable tool for guiding treatment decisions in LVO-AIS, particularly when CTP is not feasible.