[Supratentorial hemorrhage of hypertensive origin during operation: an unusual complication of surgery on the posterior fossa in the sitting position (author's transl)].

The authors report a case of a massive hemorrhage in the basal ganglia after an uncomplicated posterior fossa intervention for removal of an isolated metastasis of a breast carcinoma. The etiology of this large hematoma was most likely secondary to a sudden rise of the arterial blood pressure during the removal of the tumor, probably due to an irritation of the vaso-motor centers of the medulla. This complication is exceptional since only two similar cases have been reported in the literature, but this possibility should be kept in mind in any patient developing a progressive hemiparesis and deterioration of the level of consciousness immediately after a sub-occipital craniectomy.