Removal of tumors in the III ventricle using the lamina terminalis approach

Abstract

Tumors in the III ventricle were totally removed in three children using a route through the lamina terminalis. The cases are discussed on the basis of computed tomography and intraoperative findings. It seems that tumors 4×2 cm in size can be successfully removed via this relatively small opening if the neuroradiological findings and the probable histology (craniopharyngioma) provide secure evidence that the tumor site and growth matrix are located in the frontal and lower portion of the III ventricle. Besides the advantage of requiring no transparenchymal access, this quick axial (orthograde) approach exerts no pressure on the hypothalamus, a complication which cannot always be avoided with the transcallosal route or the route through the foramen of Monro. Furthermore, the immediate location of the tumor behind the usually protruding lamina terminalis permits a rapid operation without exploratory characteristics. The distance between the brain surface and the tumor with this procedure is 0 cm; however, it can be up to 9 cm, depending on the age of the patient, with other approaches.