Masahiro Kitabayashi

Reconstruction of the skull base using a silicone plate during transsphenoidal surgery.

Our operative experience of reconstruction of the skull base using a silicone plate during rhinoseptoplastic transsphenoidal surgery is described. A suitably shaped plate can be easily and quickly made from a large silicone block of the type that is widely used in cosmetic surgery. The plates can be distinguished on magnetic resonance images postoperatively. We consider that this technique is of use not only for repairing the sellar floor, but also for closing a wide defect of the skull base.

Analysis of the proliferative potential of tumor cells after stereotactic radiosurgery for recurrent astrocytic tumors.

Abstract We analyzed the effectiveness of stereotactic radiosurgery (SRS) for recurrent astrocytic tumors histologically. Five patients were followed by pathological examination after radlosurglcal treatment of recurrent astrocytic tumors. Histological diagnoses at the time of the last operation before SRS were Daumas-Duport grade II in two patients and grade IV (glioblastoma) in three patients. No histological diagnoses at the time of SRS were identified in any patients. Contrast enhanced lesions enlarged gradually on magnetic resonance (MR) images after SRS, and local control by SRS was judged as progressive disease radiologically in all patients. Four of five patients received re-operation after SRS, and the other patient died without re-operation and underwent post-mortem examination. After SRS, Ki-67 labeling indices (Lis) of recurrent astrocytomas initially diagnosed as grade II were 2.6% and 1.1%. These Us were relatively lower than those of the control group of patients with recurrent grade II astrocytomas that were not treated by SRS. Ki-67 Us of three glioblastomas after SRS were 23.5%, 18.6%, and 17.8%. These Us were significantly lower than those before SRS (2.3%, 4.5%, and 0.9%). In the autopsy case, there was a significant difference between the LI of tumor cells in the radiosurgically treated region (0.9%) and that in the untreated region (29.2%). These results suggest that the proliferative potential of malignant astrocytic tumors in the radiosurgically treated area is reduced after SRS, and that radiological enlargement of enhanced lesions on MR images is due to propagation of the residual tumor cells that were not covered by radlosurgical target volume or to radiation necrosis. SRS may be a useful therapeutic tool in multidisciplinary treatment of malignant gliomas. [Neurol Res 2000; 22: 802-808]

Benign intracranial hypertension treated with ventriculoperitoneal shunting. Case report

A 59-year-old woman complained of headaches and vomiting. On admission, neurological examination revealed bilateral choked disc and tendon hyperreflexia. Lumbar puncture showed a high opening cerebrospinal fluid (CSF) pressure (195 mmH2O); however, protein and sugar levels were normal. The CSF was clear and watery. Computed tomography showed that the bilateral white matter was of low density and the ventricles were compressed bilaterally.