Cerebellar hemorrhage arising postoperatively as a complication of supratentorial surgery: a retrospective study

Object. Postoperative cerebellar hemorrhage as a complication of supratentorial surgery is an increasingly recognized clinical entity. So far, it has remained unclear whether this complication constitutes an intraoperative or postoperative event. The observation of such cases prompted the authors to analyze retrospectively their series of supratentorial craniotomies. The aim of this study was to determine the incidence of cerebellar hemorrhage and its temporal relationship to supratentorial surgery. Methods. The authors reviewed discharge notes and reports on postoperative computerized tomography (CT) scans for 1650 patients who had undergone supratentorial craniotomy between January 1998 and February 2001. The retrospective study led to the identification of 10 patients who had sustained cerebellar hemorrhage as a complication of supratentorial surgery. Because it was routine to perform CT scanning following craniotomy, an early CT scan obtained within the 1st postoperative hour (mean 24 minutes after wound closure) was available in eight of the 10 patients. In seven of these patients no hemorrhage was found immediately after surgery, and in only one patient was there the suspicion of cerebellar hemorrhage. In the whole series of 10 patients, cerebellar hemorrhage was detected during the later postoperative course, after a mean interval of 7 hours and 35 minutes (range 1 hour and 49 minutes-144 hours) following surgery. The incidence of cerebellar hemorrhage was 0.6% of all patients who underwent supratentorial surgery. Among patients suffering from epilepsy the incidence was 4.6%, and in those patients who underwent temporal lobe resection it was 12.9%. Conclusions. The authors have demonstrated that cerebellar hemorrhage as a complication of supratentorial surgery arises not as an intraoperative event, but as a postoperative event. Resective nontumorous temporal lobe procedures place patients at particular risk for this complication. Evidence suggests that the complication might be precipitated by postoperative suction drainage.