Optimal Tissue Reperfusion Estimation by Computed Tomography Perfusion Post-Thrombectomy in Acute Ischemic Stroke

Area of Science:

• Neurology
• Interventional Neuroradiology
• Stroke Imaging

Background:

• Modified Thrombolysis in Cerebral Infarction (mTICI) score ≥2b signifies successful reperfusion in acute stroke.
• Correlation between mTICI scores and dynamic perfusion imaging (tissue optimal reperfusion - TOR) post-endovascular therapy is understudied.
• Understanding reperfusion dynamics is crucial for optimizing acute stroke treatment.

Purpose of the Study:

• To investigate the proportion of tissue optimal reperfusion (TOR) across different mTICI grades after endovascular therapy for acute ischemic stroke.
• To compare the efficacy of mTICI grading with TOR in predicting functional outcomes.

Main Methods:

• Retrospective analysis of 82 acute ischemic stroke patients undergoing endovascular therapy (2018-2019).
• Perfusion imaging (CTP or MRP) performed pre- and post-intervention.
• Tissue optimal reperfusion (TOR) defined as >90% Tmax+6 volume reduction.

Main Results:

• A statistically significant difference in TOR proportions was observed across mTICI grades (P=0.003).
• TOR rates: mTICI 0-2A (0%), mTICI 2b (50.0%), mTICI 2c (80.0%), mTICI 3 (81.3%).
• Lower age, shorter onset-to-tPA time, and achieving TOR were associated with favorable functional outcomes.

Conclusions:

• mTICI 2b indicates significantly lower TOR compared to mTICI 2c and 3.
• Tissue optimal reperfusion (TOR) is a stronger predictor of favorable functional outcome than mTICI scores alone.
• Dynamic perfusion imaging offers valuable insights into reperfusion success post-endovascular therapy.