Objective:

To compare different radiographic modalities and their ability to predict functional outcome in patients with acute ischemic stroke (AIS) undergoing Endovascular Thrombectomy (EVT). 

Background:

Leptomeningeal collateral (LMC) status is associated with clinical outcome after AIS treatment. Multiple radiographic modalities have been proposed to assess collateral status. Nevertheless, there is a scarcity of studies regarding their clinical relevance as well as association with clinical outcomes.

Design/Methods:

 In this retrospective study, we included AIS patients presenting with ICA or M1 occlusion undergoing EVT with a pre-event mRS score of ≤2. CTA collaterals were classified using the Regenhardt et al.  Patients were categorized into three groups—malignant, intermediate, and symmetric. CTP Hypoperfusion Intensity Ratio (HIR) was calculated by dividing the volume of tissue with a time-to-maximum (Tmax) of >10 seconds by Tmax of >6 seconds. CTP Infarct Volume (IV) was defined as Cerebral blood flow > 30%. Associations between each marker and mRS was assessed using the Kruskal-Wallis test, and stepwise fitting of different variables within univariable, then multivariable regression analyses. 

Results:

A total of 155 patients were included in this study. 53% of them were males, and 47% were females. 43% of patients had symmetrical collaterals, while 19% had malignant collaterals. The mean CTP IV was 28±3.7, and mean CTP HIR was 0.4±0.02. CTA collateral score was associated with 90-days mRS across all statistical analysis methods, while CTP HIR was not associated with outcomes. CTP IV was only associated with outcomes when analyzed as a continuous variable.

Conclusions: