OBJECTIVE: Basilar perforator aneurysms (BPAs) are rare lesions that present a therapeutic challenge. We present 4 cases of ruptured BPAs treated either conservatively or by flow diverter deployment and review the literature.METHODS: Patients (age 78, 59, 53, and 62 years) presented with World Federation of Neurological Societies grade I-IV and Fisher grade 3-4 subarachnoid hemorrhage. Initial angiography results were normal in 3 patients and necessitated a second angiography. BPA diameter was 0.5-3 mm; BPAs were located in the mid-third of the basilar artery in 2 patients and the upper third in 2 patients.RESULTS: All patients were managed conservatively. One patient experienced rebleeding 10 days after initial ictus, which required the deployment of a flow diverter in the basilar artery. One patient developed a severe spontaneous pontine ischemic stroke with severe quadriparesis and refused further imaging. He was clinically stable at 1-year clinical follow-up. The other 3 patients showed complete resolution of BPAs on control follow-up imaging.CONCLUSIONS: Ruptured BPAs are rare lesions that may heal spontaneously or be associated with spontaneous ischemic brainstem stroke or rerupture. These lesions can be managed conservatively initially with flow diverter deployment the most suitable therapeutic alternative in selected cases. Larger studies are needed to fully understand the natural history and refine the therapeutic strategy for these lesions.