Perimesencephalic Hemorrhagic-Pontine Infarction Syndrome: Miler Fisher's Hint to Subarachnoid Paramedian Artery Rupture-A Case Report.

We report a 73-year-old man transferred for evaluation of suspected aneurysmal subarachnoid hemorrhage after his first-ever thunderclap headache episode. It was noted on the second day of the disease left hemiparesis. On MRI, the hemorrhage was of the perimesencephalic type and was associated with an early right paramedian pontine infarction. Angiography did not reveal an aneurismal source for the bleeding, arterial dissection, nor vertebrobasilar vasospasm. Synchronic pontine infarction with perimesencephalic hemorrhage is an unusual syndrome ascribed to the rupture of a perforator superficial arterial segment, as described by Hochberg and Miller Fisher in a case report with autopsy. The absence of a bleeding source for subarachnoid hemorrhage and the presence of ischemic paramedian pontine perforator reinforce the role of artery rupture in the etiology of this case in particular but also as the main cause of concomitant hemorrhagic-ischemic brainstem syndrome. The patient had a satisfactory recovery and was treated with antiplatelet therapy, statins, and rehabilitation. Paramedian pontine infarction and perimesencephalic hemorrhage should be considered a concomitant hemorrhagic-ischemic syndrome suggesting basilar perforator rupture as the etiologic mechanism of the stroke, although rare.