The authors report a case of a hemorrhage of the brainstem after craniotomy for resection of a huge arachnoid cyst of the sylvian fissure on the left hemisphere. The previous simptomatology included clinical signs of increased intracranial pressure, and the computerized tomography showed midline shift. Some factors may contribute to brain hemorrhage post-operatively: cerebral edema, ipsilateral changes in the venous reflux and blood perfusion, although the physiopathology remains obscure. A more careful approach is suggested in such cases with intracranial hypertension.
arachnoid cyst; craniotomy; brainstem hemorrhage; surgical complication