Article Text
Abstract
Background Pretreatment baseline ASPECT score is used as a useful predictor of clinical outcome in acute ischemic stroke revascularization; post-treatment ASPECT analysis has not been used to analyze revascularization effects. We hypothesize assessment of post-treatment ASPECT areas may give information on differences between revascularization effects and clinical outcome in competing revascularization studies.
Purpose To examine differences in post-treatment ASPECT regions affected in the Interventional Management of Stroke (IMS) I/II vs Solitaire Studies.
Methods 24-hr. CT/MR of subjects from the Solitaire Study and from IMS I/II with ICA-T, M1, or M2 occlusion treatment was reviewed. We recorded the degree of revascularization and post-treatment ASPECT areas affected. The cohort was divided into two categories based on site of arterial occlusive lesion (AOL) as Group A (ICA-T or M1 proximal to lenticulostriates) and Group B (M1 or M2 distal to lenticulostriates). The affected ASPECT regions for both groups were then compared for the two studies.
Results 96 subjects from Solitaire Study (67 Group A, 29 Group B) and 68 from IMSI/II (36 Group A, 32 Group B) with index AOL had complete imaging available for review. Abstract P-0026 figure 1 and 2 displays ASPECT areas for both groups in both studies. Incidence of basal ganglia involvement was similar in both studies, and was frequently found in subjects with AOL beyond the striate arteries. IMS subjects had more peripheral cortex zones affected compared to Solitaire subjects in both groups A and B (p=0.01). Patients in IMSI/II also had more frequent involvement of insular cortex compared to Solitaire subjects in both groups A and B (p<0.001).
Conclusion In AOL beyond the origin of lenticulostriate arteries, involvement of basal ganglia may indicate initial deep small vessel occlusion, or early recanalization prior to arteriography. Greater involvement of peripheral cortex and insula in IMS may be an effect of less complete or delayed revascularization, or increased distal emboli (poorer reperfusion). Better preservation of distal tissue following more rapid and complete revascularization with Solitaire is hypothesized.Solitaire Revascularization was not associated with increased basal ganglia ischemia, as might be anticipated due to compression during stent deployment or microembolism during clot retrieval. Other clinical and imaging factors affecting infarct volume will be discussed.
Competing interests None.