Middle Fossa Approach for Resection of a Petrous Apex Cholesterol Granuloma: 2-Dimensional Operative Video.

Abstract

Cholesterol granulomas (CGs) are the most common cyst of the petrous apex. 1 The management options for CG include observation and surgical resection. Surgery is complicated by the proximity of these lesions to critical neurological and vascular structures, as with many skull base lesions; however, if left untreated, their growth may lead to mass effect resulting in conductive hearing loss, cranial nerve dysfunction, tinnitus, and/or chronic headaches. 2,3 In this video, we present the case of 52-year-old woman who presented with medically refractory right retro-orbital headaches. MRI revealed a large, right-sided petrous apex cystic structure consistent with a CG. Computed tomography of the head demonstrated bony remodeling. Given the large size of the cyst and the patient's symptoms, surgery was proposed, and the patient agreed. We performed a middle fossa craniotomy and elevated the dura from the floor of the middle fossa, working posteriorly from the petrous ridge and extending anteriorly. The cyst was exposed and decompressed, and its wall was then dissected off. After all cystic components were removed, the cavity was packed with abdominal fat, which is believed to prevent cyst reaccumulation. Postoperative MRI demonstrated good resection, and the patient reported complete resolution of her headaches. The patient consented to the procedure as shown in this operative video and gave informed written consent for use of her images in publication.