Effectiveness of multiple endoscopic fenestrations for the treatment of Sylvian fissure arachnoid cysts: a multicenter study

Arachnoid cysts are usually asymptomatic lesions. However, they can sometimes cause intracranial hypertension, headache, seizures, focal neurological deficits, and bleeding. The most commonly used surgical techniques are microsurgical cyst fenestration/excision/drainage, cyst shunting, and endoscopic procedures. We aimed to investigate the success of different surgical techniques.

Between 2000 and 2021, patients with Sylvan fissure arachnoid cysts who received treatment via an endoscopic approach chosen as the first-line treatment in three centers were enrolled. All case notes and radiological studies were evaluated retrospectively.

The study included 131 (female, n = 28; male, n = 103) patients with a mean age of 87.04 ± 66.76 (range, 0-216) months. Of the patients, 25 had Galassi type II left-sided arachnoid cysts, 33 had Galassi type II right-sided arachnoid cysts, 40 had Galassi type III left-sided arachnoid cysts, and 32 had Galassi type III right-sided arachnoid cysts. No difference was found between patients who underwent single and multiple fenestrations in terms of Galassi type, side, clinical outcome, and cyst size (p > 0.05). On the contrary, the rate of additional surgical intervention was lower in patients with multiple fenestrations than in those with single fenestration (36.10% vs. 5.30%; p < 0.001).

Endoscopic fenestration of Sylvian fissure arachnoid cysts is a good alternative to open surgery or cystoperitoneal shunting, and the number of fenestrations made during this surgery decreases the need for a second surgical procedure.