Epidermoid Cyst (inclusion cyst), pineal region, quadrigeminal plate cistern, MedPix™ : 3483

Welcome! It's Thursday, September 02, 2010 :: :: ::

TOPIC and DISCUSSION :: :: :: ::

Epidermoid Cyst (inclusion cyst), pineal region, quadrigeminal plate cistern
Topic 3483 - Created: 2001-12-10 10:30:37-05 - Modified: 2004-03-03 02:10:31-05

ACR Index: 1.3

The epidermoid cyst (more properly "epidermoid inclusion cyst") is a true cyst lined by squamous epithelium. These may be congenital or acquired (e.g. post traumatic), and occur when the ectoderm is pushed below the surface, creating an enclosed space or "pocket" with a lining.

The cyst grows slowly by the desquamation of the lining, accumulating keratin (protein) and occasionaly cholesterin debris.

DDX:

Arachnoid Cyst

Dermoid Inclusion Cyst

Teratoma (well-differentiated)

Distinction from arachnoid cyst is assisted by MR using FLAIR and/or DWI (Diffusion Weighted Imaging). On both FLAIR and DWI, an arachnoid cyst should be isointense to CSF - whereas a true epidermoid may have a variable or heterogeneous signal and will deviate from CSF intensity.

Show Images Here - :: Switch to Image Summary -