Infratentorial epidermoids.

Infratentorial epidermoids are rarely seen in the lifetime of a neurosurgeon. Most published series consist of a dozen or so cases. In a period of 20 years we operated on only 6 such patients. Five are doing excellently, one patient died two and a half months after operation of a fulminating infection. The follow-up is of 20 years, 9 years, and 3 years of the first three patients, while the remaining three were operated during the last year. Such an accelerated pace of epidermoid incidence in our department during the last year may be fortuitous, but may also be an indication that, many patients with vague complaints who had an epidermoid, had been missed in the past. Undoubtedly, the CT scan has greatly facilitated the diagnosis of epidermoid cysts, whether infra- or supratentorial. Diagnosis, however, hinges on suspicion or awareness on clinical grounds of the possibility of an infratentorial epidermoid. The analysis of the clinical presentation in our 6 cases, seems to allow the division of infratentorial epidermoids into those that are posteriorly located, which uniformly manifested at some stage of illness raised intracranial pressure, and the anterior epidermoids in the cerebello-pontine angle characterized by the insidious involvement of cranial nerves. Computerized tomography, in some cases with the adjunct of Metrizamide cisternography, confirms the diagnosis and delineates the spread of the lesion.(ABSTRACT TRUNCATED AT 250 WORDS)