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[Epidermoid cyst of the cerebellopontine angle. A surgical series of 10 cases and review of the literature].

Epidermoid cyst or cholesteastoma is a congenital slow growing lesion. It usually arises in the paramedian cisterns of the posterior fossa. Its incidence varies between 0.2 and 1% of all intracranial tumors. The cerebello-pontine angle (CPA) is the most common localization. Our study reports 10 observations of CPA epidermoid cysts, treated in our department between 1989 and 1999. The age of our patients ranged from 20 to 45 years, with male predominance. The patients were admitted with symptoms of cerebello-pontine angle syndrome or signs of posterior fossa tumor. CT-scan was performed in all cases and MRI was performed in 5 patients. The audiometric explorations only provided an orienting contribution. Treatment was exclusively surgical. The retro-sigmoid approach was used in 6 cases, the sub-occipital in 30% and a subtemporal approach in one case. Total resection of the epidermoid cysts was accomplished in 4 cases, and subtotal resection in 4 cases. Two patients underwent partial resection and underwent a revision procedure. The histological examination showed an epidermoid cyst in all cases. The clinical course was controlled in 6 patients: 4 patients recovered and became symptom free. A persisting neurologic deficit was observed in two cases (hearing loss, dysphonia); 4 patients were lost to follow-up. Epidermoid cyst is a benign tumor. Total resection is the ideal treatment, but we have to be aware, taking into consideration the adherence of the tumor to neurovascular structures, of the risks at attempting total resection.