Remote cerebellar hemorrhage after supratentorial surgery

OBJECTIVE: Remote cerebellar hemorrhage (RCH) is an infrequent and poorly u nderstood complication of supratentorial neurosurgical procedures. We retro spectively compared 42 patients who experienced RCH with a case-matched con trol cohort, to delineate risk factors associated with the occurrence of th is complication. METHODS: Between 1988 and 2000, 42 patients experienced RCH after supratent orial neurosurgical procedures at our institution. Diagnoses were made on t he basis of postoperative computed tomographic or magnetic resonance imagin g findings in all cases. The medical records for these patients were review ed and compared with those for a control cohort of 43 patients, matched for age, sex, surgical lesion, and type of craniotomy, who were treated during the same period. RESULTS: RCH most commonly occurred after frontotemporal craniotomies for u nruptured aneurysm repair or temporal lobectomy and was frequently an incid ental finding on postoperative computed tomographic scans. However, some ca ses of RCH were associated with significant morbidity, and two patients die d. Preoperative aspirin use and elevated intraoperative systolic blood pres sure were significantly associated with RCH (P = 0.026 and P = 0.036, respe ctively). Pathological findings for two cases demonstrated hemorrhagic infa rctions in both. CONCLUSION: RCH most commonly follows supratentorial neurosurgical procedur es, performed with the patient in the supine position, that involve opening of cerebrospinal fluid cisterns or the ventricular system (such as unruptu red aneurysm repair or temporal lobectomy). Preoperative aspirin use and mo derately elevated intraoperative systolic blood pressure are potentially mo difiable risk factors associated with the development of RCH. Although RCH can cause death or major morbidity, most cases are asymptomatic or exhibit a benign course. Cerebellar "sag" as a result of cerebrospinal fluid hypovo lemia, causing transient occlusion of superior bridging veins within the po sterior fossa and consequent hemorrhagic venous infarction, is the most lik ely pathophysiological cause of RCH.