ENDOSCOPIC EXPLORATION OF THE FOURTH-VENTRICLE

Regarding to the upcoming techniques in neuroendoscopy the IVth ventri cle was examined. First in a series of 30 fresh and fixed anatomical s pecimens - the vessels injected with LATEX - the fourth ventricle was investigated endoscopically. There are three possibilities to reach th e IVth ventricle: coming from the IIIrd ventricle via the aqueductus c erebri, using the basal cisterns through the apertura lateralis Luschk ae and coming via the cerebellomedullar cistern through the foramen of Magendi. Using different kinds of endoscopes (rigid, flexible and ste erable flexible) - diameter ranging from 5 to 9 french - with differen t optical systems (0 degrees, 5 degrees, 30 degrees, 75 degrees) and d ifferent light sources (Halogen, Xenon) the anatomical details seen un der the endoscope and the topographical landmarks of the approaches we re investigated, presented and discussed. Based on the experience at t he end of the cadaver work a short comment on which kind of equipment seems the best was given. A series of 14 clinical cases was presented as the second part of the study (7 cases with a tumor in the IVth vent ricle - 2 metastasis, 3 gliotic tumors, 1 ependymoma, 1 medulloblastom a, 3 patients with an occluded aqueduct because of meningo-ventriculit is and 4 patients with cystic malformations). The neuroendoscopic appr oaches, the neuroanatomical details relevant for surgery and the clini cal data will be given and discussed. In general no intraoperative or postoperative complications were seen. In conclusion our experience fr om the theoretical neuroanatomical and the clinical part as well as th e advantages and disadvantages from the different kind of endoscopes a nd approaches are discussed.