Intramedullary hemangioblastoma of the medulla oblongata--two case reports and review of the literature.

We determined the treatment modality of hemangioblastoma of the brain stem on the bases of our two cases and 31 cases searching from the literature since 1960 which were treated surgically. Hemangioblastomas of the brain stem were categorized according to one of three locations: hemangioblastoma of the fourth ventricle attached to the floor of the ventricle (Type A), hemangioblastoma of the fourth ventricle partially embedded in the floor of the ventricle (Type E), and intramedullary hemangioblastoma of the medulla oblongata (Type I); and were evaluated their clinical features including the operative mortality and morbidity of each location. In our two cases of Type I hemangioblastoma, Case 1, removed partially, died due to sleep apnea and Case 2 lead to normal school life after hemangioblastomas were removed radically. In our review of the 33 surgically-treated cases, radical excision was carried out in 29 cases (87.9%). The mortality was 24.2% overall; that of Type A was 25%, Type E was 28.6%, and Type I was 14.3%. In terms of postoperative mortality, the location of the hemangioblastoma was irrelevant and radical excision was much better than partial removal. Hemangioblastomas of the brain stem could be removed radically by meticulous dissection of the tumor on distinct cleavage, even in cases of intramedullary location. Microsurgical dissection of medullary hemangioblastomas with low morbidity is feasible and prudent postoperative care is mandatory to reduce the operative mortality and morbidity.