CPA angle CPA angle mass.mass.

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Teaching pearls:
1- Epidermoid cyst is the 3rd most common CPA mass after vistibular shwannoma and meningioma.
2- High signal on diffusion and incomplete attenuation on flair is diagnostic and help to distinguish it from arachnoid cyst.
3-Diffusion can also used to diagnose recurrent epidermoid cyst.
4-75 % of epidermoid cyst occur in CPA.
   25 % in 4th ventricle.