Presentation
Vague headaches
Patient Data
A space-occupying lesion is demonstrated in the left cerebellopontine angle which has density approximating that of CSF. The lesion has scalloped borders indenting the left middle cerebellar peduncle and hemisphere. The fourth ventricle is displaced towards the right, without convincing evidence of hydrocephalus. There is no solid component and it is an isolated abnormality.
Near fluid-density lesion ( * ) in the left cerebellopontine angle distorts the adjacent cerebellar hemisphere with prominent scalloped margin (blue arrows), a characteristic feature.
Case Discussion
This case demonstrates the typical CT appearances of an epidermoid cyst, in a typical location. This patient has had this lesion for some time, previously assessed with MRI, which should be obtained in all cases.