Surgical management of petrous apex cholesterol granulomas

Objectives: To review surgical approaches for drainage of petrous apex cholesterol granulomas. define the criteria for the selection of each approach. and identify factors affecting surgical outcome. Study Design: Retrospective chart review and follow-up survey questionnaire. Setting: Tertiary neurotologic referral center. Patients: Thirty-four patients who underwent surgical treatment for symptomatic cholesterol granulomas of the petrous apex, who had a minimum of 3 months of clinical follow-up care and, in some cases, postoperative radiologic follow-up studies. Intervention: Drainage with or without removal of the cyst lining was achieved through the transcanal infracochlear, transmastoid infralabyrinthine, middle fossa, translabyrinthine, and transotic approaches. Silastic catheters were used to stent drainage sites in some cases. Main Outcome Measures: Relief of symptoms, postoperative cranial nerve function. clinical and radiologic recurrence, and need for further surgical intervention were evaluated. Imaging studies were reviewed to determine how anatomic information influenced surgical decisions and outcome. Results: Clinical improvement of symptoms was observed in 28 patients (82%). and recovery of cranial nerve function was observed in 8 of 9 affected individuals. Serviceable hearing was preserved in all but 1 patient. Five patients required revision surgery for recurrent symptoms and lesions. All 5 patients had undergone drainage procedures without the use of stents. The size of the lesion did not influence the surgical outcome. Conclusions: Determination of the appropriate surgical approach to the petrous apex is based on hearing status in the affected ear and on the anatomic relationships between the lesion and the surrounding neurovascular structures. The translabyrinthine approach is useful in nonhearing ears. In hearing individuals, anatomy permitting. the transcanal infracochlear approach with stenting is the preferred approach for drainage of petrous apex cholesterol granulomas.