Pilocytic astrocytoma originating at the cavernous sinus.

We report a case of histologically proven pilocytic astrocytoma arising within the cavernous sinus, confirmed radiographically and at operation. We discuss the implications in the context of previous reports of ectopic glioma origin. In particular, the possiblity of glioma development within glial cell islands in the peripheral segment of cranial nerves is explored.