Basilar thrombolysis in cerebral infarction (bTICI) scale: Proposal and preliminary validation of a basilar reperfusion score based on digital subtraction angiography to evaluate the efficacy of mechanical thrombectomy in acute basilar artery occlusion.

OBJECTIVES

Basilar artery occlusion (BAO) accounts for 10% of all ischemic strokes due to largevessel occlusion (LVO) and is associated with highest mortality and disability rate. The aim ofthis study is to propose a specific basilar artery reperfusion score based on digital subtraction angiography (DSA) to evaluate the efficacyof mechanical thrombectomy in patients with acute BAO.

METHODS

We conducted a retrospective analysis of a prospective database of consecutivepatients with acute BAO treated with mechanical thrombectomy within 24 h from symptomonset at a comprehensive stroke center between January-2014 and December-2023. BasilarThrombolysis In Cerebral Infarction (bTICI) scale was made using PC ASPECTS grading scoreas reference. Primary outcome was defined by a modified Rankin scale score of 0-3 (goodfunctional status) at 90-days.

RESULTS

A total of 98 patients were included (median age 70 years, 56 men). bTICI score of 10was achieved in 46 patients (46.9%), bTICI 9 in 8 patients (8.2%), bTICI 8 in 16 patients (16.3%), bTICI 7 in 4 patients (4.1%) and bTICI 0-6 in 24 patients (24.5%). On multivariable analysis, mTICI 3 was independently associated with 90-day goodfunctional status [OR 4.48 (95% CI 1.64-18.27)], while mTICI 2b-3 was not. Regarding bTICI scale, a bTICI ≥ 7 remained as independentpredictors of 90-day good functional status [OR 9.45 (95% CI 2.68-33.30)]. In our study, bTICI ≥ 7 or ≥8 is an independent predictor of 90-day good functional status (mRS 0-3) in patientswith Acute BAO treated with mechanical thrombectomy.

CONCLUSIONS

The Basilar Thrombolysis In Cerebral Infarction (bTICI) scale identified meaningful distinctions in clinical outcomes in our single-center study, showing better performance thanmTICI scale. This new scale, specific to posterior circulation stroke, may be useful in futurestudies and routine practice but this needs to be confirmed in multicenter.