Late spontaneous recanalization (SR) of an occluded internal carotid artery (ICA) has been rarely reported and the prognosis of affected patients remains elusive. In the present study, the incidence of late SR of atherosclerotic occlusion of the ICA and associated outcomes were assessed in a single center. A total of 36 patients with ICA occlusion, who underwent carotid artery stenting or vertebral artery stenting in arteries other than the occluded ICA, were prospectively included and followed up for ≥18 months. SR was diagnosed by color Doppler ultrasound imaging. The incidence of late SR, the functional outcome and the incidence of adverse cardiovascular events in these patients were evaluated. During the follow-up, three patients had late SR of the occluded ICA (8.3%). All patients had vascular events prior to the confirmation of late SR of the ICA. Subsequent to SR, the patients were clinically stable with preserved functional ability, based on the Modified Rankin Scale. Of these patients, one suffered from re-occlusion of the recanalized ICA without presenting with any novel significant symptoms. In conclusion, patients with late SR of the ICA appear to have preserved functional ability and favorable clinical outcomes. Large-scale cohorts are required to determine the clinical characteristics that contribute to the incidence of late SR of the ICA.
Keywords: cerebral artery occlusion; cohort study; internal carotid artery; late spontaneous recanalization.