A white epidermoid is a rare type of epidermoid cyst that has a high protein content and has a number of causes.
In some cases the intrinsic high T1 signal is due to a high protein content, which renders them relatively hyper-attenuating on CT 3. In this case T2 signal can vary from hyper to hypo intense.
Alternatively, high T1 signal can be due to high lipid content (mixed triglycerides and no cholesterol), which are associated with fat density on CT 3. Additionally intrinsic high T1 signal can be seen in rare instances of haemorrhage into the cyst 3.
- 1. Osborn AG, Preece MT. Intracranial cysts: radiologic-pathologic correlation and imaging approach. Radiology. 2006;239 (3): 650-64. doi:10.1148/radiol.2393050823 - Pubmed citation
- 2. Dähnert W. Radiology Review Manual. Hubsta Ltd. (2007) ISBN:0781766206. Read it at Google Books - Find it at Amazon
- 3. Chen CY, Wong JS, Hsieh SC et-al. Intracranial epidermoid cyst with hemorrhage: MR imaging findings. AJNR Am J Neuroradiol. 2006;27 (2): 427-9. AJNR Am J Neuroradiol (full text) - Pubmed citation