Middle fossa approach for total resection of petrous apex cholesterol granulomas: use of vascularized galeofascial flap preventing recurrence

Cholesterol granulomas (CGs) of the petrous apex (PA) are rare, benign, expanding lesions. Surgical treatment is recommended for patients with symptomatic disease; however, the optimal surgical procedure is still controversial due to high recurrence rates. The main treatment strategy is divided into drainage and complete resection. We advocate radical resection of the lesion by the middle fossa approach and reconstruction with a vascularized galeofascial flap. A 10-year retrospective case review of 17 patients undergoing surgical treatment of PA CGs between 2000 and 2010 was undertaken. Operative outcomes and surgical complications were analyzed. In addition, our operative method and the related anatomy are described from cadaveric dissections. All but 1 patient was operated on via a middle fossa approach. Using the middle fossa approach, radical resection of all PA CGs was achieved with obliteration of the cyst cavity using a vascularized flap. Important surrounding structures included the internal auditory canal, cochlea, petrous carotid artery, and abducens nerve. There was 1 death caused by internal carotid artery occlusion. No other major complications or cranial nerve deficits occurred postoperatively. Clinical recurrence occurred in 1 patient (5.9%). Our technique of radical resection and reconstruction with a vascularized flap has the advantage of being less invasive with less cosmetic deformity and allows preservation of cranial nerve function with a low recurrence rate. Knowledge of the surgical anatomy and the characteristics of CG is prudent because important neurovascular structures may be exposed behind the CG wall due to bony erosion.