Biportal endoscopic management of third ventricle tumors in patients with occlusive hydrocephalus: technical note.

Abstract

Objective: To present the feasibility and advantages of the biportal endoscopic management of posterior third ventricle tumors. As a result of recent developments in neuroendoscopy, classical third ventriculostomy has become a standard single burr hole procedure and a real alternative to shunting in the treatment of occlusive hydrocephalus. In patients with third ventricle tumors occluding the aqueduct, the acute development of hydrocephalus may often precede debilitating focal symptoms and signs. Forty percent of those tumors are radiosensitive, rendering craniotomy unnecessary. The goal of primary management is the alleviation of raised intracranial pressure and determination of the histological nature of the tumor. Cerebrospinal fluid shunting and the performance of a computed tomography- or magnetic resonance imaging-guided biopsy are generally suggested as the methods of choice.

Methods: Three patients with posterior third ventricle tumors and acute hydrocephalus were treated in one session by computed tomography-guided endoscopic third ventriculostomy and endoscopic tumor biopsy was performed by means of two rigid ventriculoscopes.

Results: Ventriculostomy was performed in three patients, and tumor biopsy was performed in two patients. The maximum 40-minute operation did not involve mortality or morbidity. Histological findings were established in all patients. In two patients with malignant infiltrative tumors, postoperative radiotherapy was used; in one patient with a small cavernoma, no further measures were taken. At the 6-month follow-up, flow-sensitive magnetic resonance imaging confirmed ventriculostomy patency in all patients.

Conclusion: The biportal endoscopic approach allowed independent visual control of both procedures, safe passages of the ventriculoscopes via the narrow foramen of Monro, and facile control of the intracranial pressure in the ventricles via the available four irrigation channels during the performance of tumor biopsy and fenestration of the floor of the third ventricle. In selected patients with infiltrating posterior third ventricle tumors, this procedure and postoperative radiotherapy may be an alternative to direct surgery or to shunting and performance of image-guided biopsy.