Computed Tomography Perfusion After Thrombectomy

Background and Purpose- Despite recanalization, almost 50% of patients undergoing endovascular treatment (EVT) experience poor outcome. We aim to evaluate the value of computed tomography perfusion as immediate outcome predictor postendovascular treatment. Methods- Consecutive patients receiving endovascular treatment who achieved recanalization (modified Thrombolysis in Cerebral Ischemia mTICI 2a-3) underwent computed tomography perfusion within 30 minutes from recanalization (CTPpost). Hypoperfusion was defined as the Tmax>6 second volume; hyperperfusion as visually increased cerebral blood flow/cerebral blood volume with reduced Tmax compared with unaffected hemisphere. Dramatic clinical recovery (DCR) was defined as 24-hour National Institutes of Health Stroke Scale score ≤2 or ≥8 points drop. Delayed recovery was defined as no-DCR with favorable outcome (modified Rankin Scale score 0-2) at 3 months. Results- We included 151 patients: median National Institutes of Health Stroke Scale score 16 (interquartile range, 10-21), median admission ASPECTS 9 (interquartile range, 8-10). Final recanalization was the following: mTICI2a 11 (7.3%), mTICI2b 46 (30.5%), and mTICI3 94 (62.3%). On CTPpost, 80 (52.9%) patients showed hypoperfusion (median Tmax>6 seconds: 4 cc 0-25) and 32 (21.2%) hyperperfusion. There was an association between final TICI and CTPpost hypoperfusion(median Tmax>6: 91 56-117, 15 0-37.5, and 0 0-7 cc, for mTICI 2a, 2b, and 3, respectively, PPPPP<0.01). Conclusions- Hypoperfusion on CTPpost constitutes an immediate accurate surrogate marker of success after endovascular treatment and identifies those patients with delayed recovery and favorable outcome.