A Case of Dermoid in the Cerebellar Hemisphere

ABSTRACT

Dermoid cysts of the posterior fossa are benign, mostly midline, congenital brain neopasm, usually located above or behind the vermis or adjacent meninges2)18)20), Dermoid lesions are slow growing and may become quite large before producing signs and symptoms12). We have recently experienced a case of dermoid which arised in cerebellar hemisphere. A 32-year old woman who had a history of chronic headache at morining was visited in our department and she was also complained of a egg-sized plapable mass which was growing nature, non-tender, soft, and movable on the right occipital area. On admission, there were no specific localizing and lateralizing neurological abnormalities. Unenhanced CT scan shows hypodense mass in the left cerebellar hemisphere and cystic mass at the right occipital scalp(Fig. 1. A). T1-weighted MR image shows hypointense mass in the left cerebellar hemisphere(Fig. 2. A). The Carotid angiography shows non-specific findings. Paramedian suboccipital approach was performed and mass was removed from the lleft cerebellar hemisphere. The cystic scalp mass was removed totally from the left cerebellar hemisphere. The cystic scalp mass was removed totally from the right occipital area. Diagnosis of dermoid cyst was confirmed pathologically by the specimens obtained from two different sites, left cerebellar hemisphere and right occipital ccalp.