Epidermoids can rutpure causing chemical meningitis.

This can lead to vasospasm which can lead to devastating infarcts

Case in Point

4.9.13 "White Epidermoid"

http://3s.acr.org/CIP/CaseView.aspx?CaseId=yAIg7PFcQTQ=

Reference:

http://thejns.org/doi/pdf/10.3171/JNS-07/08/0426