Neuroendoscopic approach to arachnoid cysts.

A prospective study of seven consecutive patients with congenital arachnoid cysts treated endoscopically is reported. The ages of the patients at the time of diagnosis ranged from 6 to 47 years with three patients under 15 years. Two cysts were located in the posterior cranial fossa, four in the middle cranial fossa, and one in the suprasellar-prepontine area. The patients' symptoms included headache, seizures, vomiting, nausea, dizziness, balance problems, and precocious puberty. The authors performed cystocisternostomies and ventriculocystostomies via burr holes with the aid of a universal neuroendoscopic system. Minor bleeding was easily controlled by rinsing. In one case, the endoscopic procedure had to be abandoned because of significant bleeding, which obscured a clear operative view, and an open microsurgical cyst fenestration was performed. The follow-up review periods in this group of patients ranged from 15 to 30 months. There was no mortality or morbidity. Symptoms were relieved in five patients and improved in one. Precocious puberty in one case continued. In six cases, follow-up magnetic resonance images or computerized tomography scans revealed a decrease in the size of the cysts. Although the follow-up period is too short to make statements on long-term outcome, the authors recommend the minimally invasive endoscopic approach for treatment of arachnoid cysts as the first therapy of choice. Should the endoscopic procedure fail, established treatment options such as microsurgical fenestration or cystoperitoneal shunting can subsequently be performed without causing additional risk to the patient.