Presentation
Headache and history of epilepsy.
Patient Data
A well-defined, low-density lesion of near CSF attenuation noted in the right parietal parafalcine region. The lesion is extra-axial, dura based and shows no significant post-contrast enhancement. There are foci of peripheral coarse calcifications.
Case Discussion
Epidermoid cysts are benign congenital lesions and constitute less than 2% of all intracranial tumors. Like dermoids and dermal sinus, epidermoid cysts arise from the ectodermal rest cells. Epidermoids grow slowly and become symptomatic later in adulthood, unlike dermoids, which grow fast and can be symptomatic earlier in life.
In this case, the imaging features are most likely suggestive of an interhemispheric epidermoid cyst. This could be confirmed with MRI, which is unfortunately not available.