Usefulness of silicone elastomer drains in endoscopic treatment of arachnoid cysts – preliminary report

Introduction: Endoscopic technique is gaining importance in treatment of arachnoid cysts (AC). Recommended procedures include cystocisternostomy and cystoventriculostomy. Long-term patency and functional efficacy of such connections remain a topic of discussion.
Aim: To present early and long-term outcome after endoscopic cystocisternostomy and cystoventriculostomy, in which functional efficacy was supported with a silicone elastomer catheter.
Material and methods: The study included 13 adults with symptomatic AC treated during an 8-year period. In 7 cases of cysts of the lateral cerebral fissure, cystocisternostomy with optic chiasm cistern, carotid artery cistern or prepontine cistern was performed. Six arachnoid cysts located on the brain convexity were opened to the lateral ventricle by cystoventriculostomy. Because of the anatomical situation, in none of the cases was the communication wide enough to warrant long-term patency, which was secured by use of a silicone elastomer catheter or a set of catheters. Results of the treatment were assessed based on predefined clinical and radiological criteria. The follow-up period ranged from 2.5 to 6 years.
Results: Clinical condition improved in 11 patients (84.6%). In 12 patients (92.3%) the size of the cyst decreased. Significant changes occurred 6-12 months after the procedure. No improvement was noted in half of patients with epilepsy, and a small radiological improvement was noted in cysts of the lateral cerebral fissure. Two patients required prolonged observation because of onset of asymptomatic subdural haematoma.
Conclusions: Regarding safety, replicability, efficacy and low complication rate, use of a silicone elastomer catheter is a promising solution in the endoscopic treatment of selected patients with AC.