Problems In The Pyramid

Question:  A 32 year old male is referred for a petrous apex lesion identified on an MRI obtained for headache.  Exam demonstrates normal cranial nerve function and a normal TM.  The lesion appears hyperintense on T1 and T2 sequences and does not enhance with gadolinium.  What is your diagnosis?  [Answer will be posted with next week's new question]

Answer to last week's question, "Smaller Isn't Better" (March 27, 2017)

Excessive cephalic trim.