1. To review the anatomy of petrous apex including its critical relationship with adjacent structures.
2. To demonstrate the spectrum of pathologies involving the petrous apex.
A lesion at the petrous apex carries a wide differential. They include -
• asymmetrical marrow
• petrous apex cephalocoele
• petrous apicitis
• congenital cholesteatoma
• cholesterol granuloma
• mucocoele of petrous apex
• benign tumours
o meningioma, schwannoma
• malignant tumours
o skull base chondrosarcoma
o skull base chordroma
o plasmacytoma
o metastatic lesion
• aneurysm of terminal internal carotid artery
Given its location, the petrous apex is susceptible to multiple pathologic processes. Most of these lesions have characteristic MRI and CT appearances that can often allow a precise diagnosis. Cholesterol granuloma is the most comon cystic lesion whereas Chondrosarcoma is the most common solid lesion at the petrous apex.
Agarwal, A,
Petrous Apex: Anatomy and Pathological Spectrum. Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL.
http://archive.rsna.org/2012/12025844.html
