[Surgical treatment of brain stem lesions with reference to cavernous angioma]

The surgical indications for localized brain stem lesions were evaluated retrospectively through the clinical results of 14 patients: 5 cavernous angiomas and 9 gliomas. Cavernous angiomas were located in fourth ventricle floor (2 cases), in dorsal midbrain (1 case), in right cerebellar peduncle (1 case), and in medulla oblongata (1 case). Those cases had direct surgery because of relapse of clinical symptoms and enlargement of the lesions on follow-up MR imagings. Each lesion was extirpated totally. Consequently, the majority of neurological deficits before operation improved. Therefore, radical extirpation in brain stem cavernous angioma was strongly recommended. Also, total, subtotal resection was performed for gliomas localized in brain stem: 2 low grade astrocytomas, 3 malignant astrocytomas, 3 plexus papillomas, and 1 ependymoma. Most of cases improved without new neurological deficits after surgery. In addition, MR imaging was considered to be essential to accurate diagnosis and surgical strategies for brain stem lesions.