Midbrain stroke with angiogram-negative subarachnoid hemorrhage mimicking a perimesencephalic bleed.
Angiogram-negative atraumatic subarachnoid hemorrhage (SAH) in a perimesencephalic pattern on computed tomography (CT) is associated with an almost invariably favorable prognosis with few rebleeds. We report a patient who exhibited a perimesencephalic hemorrhage pattern on CT and negative serial angiograms and who presented with severe neurologic disability from a concurrent midbrain stroke. We contend that both the acute infarction and hemorrhage arose from obliteration of a penetrating end artery. Possible etiologies of angiogram-negative SAH, including perimesencephalic hemorrhage, are discussed.
Ney
John P
JP
Department of Neurology, Walter Reed Army Medical Center, Washington, DC, USA.