BACKGROUND Hemangioblastomas of the medulla are rare and seldom reported. Surgical resection of medullary hemangioblastomas is associated with high morbidity and mortality rates. We present a unique institutional experience over a 12-year period. METHODS Between 1987 to 1998, 47 hemangioblastomas were surgically resected and analyzed retrospectively. The follow-up ranged from 6 to 136 months with an average of 35 months. RESULTS Thirty-nine single hemangioblastomas were distributed in 3 anatomical areas: pontomedullary, medullary, and cervico-medullary. They were either focal intramedullary or dorsal exophytic. There were cyst formations in 97.4% of the single hemangioblastomas. The major feeding arteries and the tumor blush could be clearly visualized on angiogram, sometimes even on MRA. All medullary hemangioblastomas were radically removed. Postoperatively, 61.5% patients had clinical improvement, two patients' symptoms remained unchanged and 11 patients deteriorated; of the latter, 8 patients improved later with proper therapy, and 2 patients died. CONCLUSION Preoperative diagnosis of medullary hemangioblastoma is possible with MRI. With improved microsurgical technique and better understanding of the vascular pattern of the tumor, total surgical resection can be performed with <5% mortality. The surgical strategy is en bloc excision, as piecemeal resection can lead to uncontrollable hemorrhage. Removal of large solid hemangioblastomas may result in severe postoperative edema and/or hemorrhage in the medulla affecting the respiratory and vagal centers. Preoperative embolization through the posterior inferior cerebellar artery (PICA) can be helpful in this situation. (C) 2001 by Elsevier Science Inc.