Operative approach to mediosuperior cerebellar tumors: occipital interhemispheric transtentorial approach.

BACKGROUND The transtentorial approach is well known as an approach to the pineal region. We have modified this approach for mediosuperior cerebellar tumors. METHODS We describe six cases of tumor excision in this region using an occipital interhemispheric transtentorial approach. RESULTS The lesions were easily accessible and the tumor was totally removed by this modified approach in all cases. Transient visual field disturbance with spontaneous recovery occurred in two patients. The lateral margin of the tumor was accessed easily up to 35 mm from the midline on the operative side and up to 17 mm from the midline on the contralateral side. CONCLUSION This approach proved to be very useful for mediosuperior lesions of the cerebellum, without causing any neural structural damage, and allowed for a wider operative field.