Radiographic diagnosis, surgical treatment, and long-term follow-up of cholesterol granulomas of the petrous apex.

Cholesterol granuloma is an unusual lesion of the petrous apex. Accurate preoperative differentiation of the various lesions of the petrous apex by computed tomography scanning only has been difficult. We reviewed the clinical findings, computed tomography and magnetic resonance imaging scans, surgical approaches, and long-term follow-up in 10 patients with cholesterol granuloma of the petrous apex who were seen between 1971 and 1988. Headache and deficits of the 5th, 6th, 7th, and 8th cranial nerves were common presenting symptoms. Magnetic resonance imaging with special imaging techniques was accurate in diagnosing cholesterol granuloma in four patients preoperatively and three patients prior to revision surgery. The optimal surgical approach was chosen on the basis of clinical and radiographic findings and included the transsphenoidal, infralabyrinthine, transcochlear, and suboccipital routes. Our review reveals that magnetic resonance imaging is more specific than computed tomography in establishing a preoperative diagnosis and is also the technique of choice in follow-up. The long-term results are discussed.