Recurrent Bleeding After Perimesencephalic Hemorrhage: Case Report and Review of the Literature.

Background: Perimesencephalic hemorrhage (PMH), a subtype of nonaneurysmal subarachnoid hemorrhage, is characterized by a typical pattern of localized hemorrhage on head computed tomography. PMH is usually associated with a benign clinical course, and a lower incidence of complications such as vasospasm and rebleeding.

Case Description: We present the cases of a man aged 28 years and a woman aged 21 years with no relevant medical history who experienced recurrent, spontaneous episodes of PMH within the course of 7 days and 29 months. No precipitating causes were identified.

Conclusions: There are only a couple of case reports of recurrent PMH, some of which were defined questionably. We review the reported cases and discuss the possible causes and long-term outcomes. Neurointerventionalists and neurosurgeons should be aware that the risk of recurrent hemorrhage of PMH does exist, although it is rather low. Even after early or late rebleeding, prognosis of PMH is excellent.