Intracranial hemorrhage (ICH) is one of the major adverse events related to the endovascular management of acute ischemic stroke. It is important to evaluate the risk of the ICH as it may result in clinical deterioration of the patients. Development of tools which can predict the risk of ICH after thrombectomy can reduce the procedure-related morbidity and mortality. 

The aim of the study was to figure out if the 2D parenchymal blood flow could potentially act as an objective predictor for Intracranial hemorrhage (ICH) after endovascular treatment of acute ischemic stroke.

2D parenchymal blood flow was used to evaluate pre and post thrombectomy DSA series of patients with acute ischemic stroke in the anterior circulation. A recently developed software allows the separation of the vascular filling and parenchymal blush signals using band-pass and band-reject filtering to allow for greater visibility of the parenchyma offering better visual indicator to the effect of treatment. The ‘wash in rate’ (the rate at which contrast increases from arrival to peak intensity) was selected as the parameter of interest to predict ICH.

According to the presence or absence of signs of intracranial parenchymal hemorrhage in the follow up dual energy CT brain scans, the patients were classified into Hemorrhagic, and Non-hemorrhagic group (15 patients each). The only significant difference between the groups is the calculated wash in rate after thrombectomy (p=0.024). Cut off value of wash in rate after thrombectomy was suggested as 11925.0 with 60% sensitivity to predict the hemorrhage and 93.3 % specificity.

Elevated parametric parenchymal blood flow ‘wash in rates’ after thrombectomy may be associated with increased risk of hemorrhagic events.