What are petrous apex lesions?
Petrous apex lesions are abnormalities that occur in the tip of the bone in the skull next to the middle ear. The most common type of petrous apex lesion is benign cholesterol granulomas, which are cysts. Other petrous apex lesions include cholesteatomas, petrous apicitis, petrous apex effusion, and bone cancer.
Most petrous apex lesions are benign. However, patients with other types of cancer may develop metastatic petrous apex lesions. These are malignant tumors that originate as cancer elsewhere in the body and then spread to the brain (metastatic).