Thrombectomy for Posterior Communicating Artery Occlusion: Report of an Extremely Rare Case, Review, and Technical Nuance.

Occlusion of the posterior communicating artery in isolation, without tandem lesions, is extremely rare. To our knowledge, only one prior report has described mechanical thrombectomy on a pure posterior communicating artery occlusion. This report describes the diagnostic and technical nuances involved in treating such an occlusion via mechanical thrombectomy. A 70-year-old male was admitted to our emergency department with left-sided hemiparesis. A computed tomography scan excluded intracranial hemorrhage. Follow-up computed tomography angiography and perfusion imaging were performed. The right P1 segment cannot be appreciated on computed tomography angiography, suggesting occlusion. Mechanical thrombectomy with a combined stent-aspiration technique achieved thrombolysis in cerebral infarction grade 3 in one pass. The patient tolerated the procedure well and was discharged to a rehabilitation hospital with a modified Rankin Scale score of 2. Posterior communicating artery occlusion is extremely rare, with only one documented report to date. The pressure difference between the internal carotid artery and the posterior cerebral artery across the posterior communicating artery is considerably low; thus, the likelihood of a thrombus passing from either side through the posterior communicating artery is low. In our case, the right posterior communicating artery fetal type with a normal posterior cerebral artery, where the right posterior cerebral artery is naturally hypoplastic, while the contralateral posterior cerebral artery was normal in size, thus misleading us into assuming the occlusion was in the P1 segment. We used a stent-retrieving into an aspiration catheter technique, which proved feasible and resulted in complete recanalization. Mechanical thrombectomy with the combined aspiration-stent retriever technique is feasible and safe for treating posterior communicating artery occlusion.