Endoscopic treatment of para- and intraventricular cerebrospinal fluid cysts.

This study has been made to define the role of endoscopy and the most appropriate approach and technique of endoscopic fenestration of paraventricular and intraventricular CSF cysts according to the cyst size and location. Twenty-two patients with intraventricular (13 cases) and paraventricular (9 cases) CSF cysts, operated upon by endoscopic technique in three Italian neurosurgical centers, are reviewed. Paraventricular hemispheric cysts have been treated by endoscopic fenestration from the cyst to the lateral ventricle. Midline intraventricular cysts (2 of the septum pellucidum and 4 of the velum interpositum) underwent fenestration from the right lateral ventricle to the cyst, with fenestration in both lateral ventricles in one case. Cysts of the choroid plexus have been fenestrated from the homolateral enlarged ventricle (4 cases) or from the contralateral compressed ventricle (2 cases). Twenty patients (more than 90%) were definitively cured by the endoscopic procedure, whereas only 2 patients required a shunt or a direct approach. We think that the endoscopic fenestration must be considered the treatment of choice of intraventricular and paraventricular CSF cysts.