[Surgery of intracranial epidermoid cysts. Report of 44 patients and review of the literature]

Abstract

Forty-four patients (22 males and 22 females) were admitted to our institution for an intracranial epidermoid cyst between 1980 and 2000. Their mean age was 39.9 years. The duration of the disease at admission varied between a few days and 30 years. CT-scan was performed in all cases, MRI in 33 cases with a diffusion sequence in 3. Most of the 26 patients with posterior fossa lesions were treated surgically in the sitting position, with resection of the tonsils in four cases in order to minimize cerebellar retraction. The other supratentorial tumors were operated using a fronto-temporo-pterional approach in 13 cases (with temporo-polar lobectomy in 6 cases), or a parietal transparenchymal approach in the parieto-occipital lesions (2 cases). The resection was total or subtotal (residual capsule) in 79.5% of cases. Post-operative morbidity was 13.6% and mortality 8.9%. The median follow-up was 8 years, with a recurrence rate of 4.5%. Epidermoid cysts are benign, slowly but ineluctably growing tumors which require surgical treatment. Their diagnosis has become easier, especially with the development of MRI diffusion sequences. Morbidity and mortality (morbi-mortality) reported in the literature as well as found in our series seems to be unrelated to classical aseptic meningitis (22.7% in our series) or hydrocephalus (2 cases in our series). For many authors, it may be the consequence of systematic resection of the tumor capsule. This does not seem to be the case in our series in which only 25% of the patients underwent a complete resection. Prolonged cerebral retraction could be one of the responsible factors. One of the technical proposals could be to perform a transparenchymal approach in selected patients.