Abstract Body: Objective: We aim to test the ability of CT perfusion (CTP) for predicting ischemic stroke in patients with symptomatic chronic carotid or middle cerebral artery occlusion.
Methods: This was a post-hoc analysis of the CMOSS trial (NCT01758614), a randomized controlled trial comparing extracranial-intracranial (EC-IC) bypass surgery to medical therapy in patients with symptomatic carotid or middle cerebral artery occlusion and hemodynamic insufficiency measured by CTP. Patients treated with medical treatment alone in the trial were included. Mean transit time (MTT) and relative cerebral blood flow (rCBF) from CTP were collected. The primary outcome was defined as ischemic stroke in the territory of the qualifying artery within 2 years after randomization.
Results: All 165 per-protocol patients (median age = 53.7 years, 81.2% males) treated with medical treatment alone were analyzed. Sixteen patients (9.7%) suffered from ischemic stroke in the territory of the qualifying artery during two-year follow-ups. Cut-off values of MTT>6.5s (symptomatic side) and rCBF ≤0.5 were suggested to be associated with recurrent stroke. In multivariate Cox regression, MTT (adjusted hazard ratio [HR] = 3.50, 95% CI = 1.19-10.30, p = 0.02) and rCBF (adjusted HR = 7.36, 95% CI = 2.27-23.85, p =0.001) were independently associated with the primary outcome.
Conclusion: This study demonstrated CTP-based hemodynamic evaluation had relative accuracy in predicting recurrent ischemic stroke in symptomatic patients with chronic carotid or middle cerebral artery occlusion, which can be potentially used in patient selection for stratified secondary prevention of stroke. Future studies are warranted to verify current findings.