The association between internal cerebral vein asymmetry on SWI and malignant brain edema / poor outcome in acute ischemic stroke patients with large vessel occlusion

Objective To assess whether internal cerebral vein （ICV） asymmetry on susceptibility weighted imaging （SWI） of MRI is associated with malignant brain edema （MBE） and long-term poor outcome in acute ischemic stroke （AIS） patients with large vessel occlusion （LVO）; proximal occlusion of internal carotid artery or M1 segment of middle cerebral artery. Methods Clinical and image data of AIS patients with LVO were collected. According to the signal of ICV on SWI, all patients were divided into the asymmetric and non-asymmetric ICV groups. The incidence of MBE and long-term poor outcome were statistically compared between two groups. Results Thirty-two AIS patients with LVO, including 19 in the asymmetric and 13 in the non-asymmetric ICV groups, were recruited in this study. The median NIHSS score was 17. Patients with asymmetric ICV had a significantly higher incidence of MBE （76.9% vs. 5.9%,P < 0.001）, lower proportion of 3-month good outcome （23.1% vs. 70.6%, P = 0.025） and higher 3-month mortality rate （46.2% vs. 0%,P = 0.003） compared with their counterparts with non-asymmetric ICV. Binary logistic analysis showed that asymmetric ICV was associated with the incidence of MBE in AIS patients with LVO （OR = 43.333,95%CI： 3.897-481.820, P = 0.020）. The progression of MBE was correlated with 3-month poor outcome in AIS patients with LVO （OR = 0.330,95%CI： 0.002-0.653,P = 0.025）. Conclusions For AIS patients with LVO, asymmetric ICV on SWI sequence of MRI is probably associated with the risk of MBE. Moreover, the progression of MBE may be correlated with 3-month poor outcome.