gms | German Medical Science

Objective: Surgical removal of para- and intraventricular tumours, even if radical, can be followed by obstruction of the CSF-pathways due to post-operative intraventricular cyst formation. In the past, microsurgical opening of these cysts was the only possible treatment to control intracranial hypertension. Today neuroendoscopy is a safe and effective mininvasive procedure to open ventricular arachnoid cysts, but experience with cystic tumours is still limited.

Methods: From 2001 to 2005, 7 patients with symptomatic increased intracranial pressure underwent neuroendoscopic procedures. There were 5 males and 2 females, aged from 16 to 66 years. In these patients MR imaging showed large cystic lesions, blocking the CSF flow in the ventricular spaces. All of them presented with a history of a tumour removal. The histological diagnosis was as follows: trigonal metastasis, pineal malignant teratoma, occipital oligoastrocytoma, frontal GBM, 4^th ventricular epidermoid, and 2 craniopharyngiomas. In 4 patients there was associated hydrocephalus; in the others there was at least a dilation of one ventricular cavity. Only in 1 case (trigonal metastasis) was navigated endoscopy necessary to obtain the best entry point.

Results: In every patient the CSF flow was immediately restored, with subsequent reduction of intracranial pressure and a remission of clinical symptoms. In 5 cystic tumours, a fenestration in the ventricular space was performed by endoscopicy; in 2 cases a septostomy, in 2 cases ETV, and in 1 case an aqueductoplasty was also carried out. In 2 craniopharyngiomas, an intracystic catheter connected to an Ommaya reservoir was introduced under direct visual control for subsequent intracavitary chemotherapy. After operation no relevant morbidity or mortality was observed. Only in 2 cases was there a recurrence of the cyst after 1 month. In 1 case cyst fenestration was finally repeated, in another patient microsurgical tumour removal was preferred. In the follow-up, between 1 and 5 years, 4 patients did not present any recurrent rise in intracranial pressure or tumour progression. 2 patients died due to tumour progression, without cyst regrowth after 6 months and 11 months following neuroendoscopy, respectively.

Conclusions: Neuroendoscopic cystic tumour fenestration is an effective and safe alternative method to microsurgical removal in order to treat raised intracranial pressure by rapidly restoring normal CSF flow. In selected cases, neuroendoscopic intervention should be considered as an alternative therapeutic modality to avoid a more extensive intracranial procedure.