Pseudo-Occlusion of the Internal Carotid Artery Predicts Poor Outcome After Reperfusion Therapy

This study aimed to evaluate the occurrence rate of the internal carotid artery pseudo-occlusion (ICA-PO) on 4-dimensional-computed tomography angiography and to investigate its relationship with clinical outcome after reperfusion therapy.

In this case-control study, we retrospectively reviewed our prospectively collected database for consecutive acute ischemic stroke patients who received reperfusion therapy between June 2009 and February 2017. ICA-PO was defined when the arterial segment was not opacified on peak arterial phase yet was subsequently patent after artery peak phase on 4-dimensional-computed tomography angiography. Poor outcome was defined as 3-month modified Rankin Scale of 4 to 6. Binary logistic regression was used to investigate the relationship of ICA-PO with poor outcome and the rate of reperfusion, respectively.

A total of 143 patients with isolated middle cerebral artery occlusion were included and 30 (21.0%) had ICA-PO. Patients with ICA-PO were more likely to have poor outcome (80.0% versus 37.2%; P<0.001) and a lower rate of reperfusion (45.8% versus 69.0%; P=0.033) than those without. Binary logistic regression revealed that ICA-PO was independently associated with poor outcome (odds ratio, 7.957; 95% confidence interval, 1.655-34.869; P=0.009) and reperfusion at 24 hours (odds ratio, 0.150; 95% confidence interval, 0.045-0.500; P=0.002) after adjustment. Among patients with no reperfusion, all ICA-PO patients obtained poor outcome, whereas only 45.2% non-PO patients underwent poor outcome (P=0.001).

Four dimensional-computed tomography angiography is a useful noninvasive technique to identify ICA-PO. Patients with ICA-PO are prone to undergo poor outcome from reperfusion therapy, especially when reperfusion is not achieved.