Use of the Ultrasonic Bone Aspirator for Meatal Bone Removal during Retrosigmoid Approach for Vestibular Schwannoma

Abstract

Objective: The ultrasonic bone aspirator (UBA) has several theoretical advantages with regard to safety and bone removal during skull base surgery. Herein we report our preliminary experience using the UBA for internal auditory canal (IAC) access during retrosigmoid(RS) craniotomy for vestibular schwannoma(VS) resection. Methods: Retrospective review (2011–2015) of consecutive patients undergoing RS craniotomy for VS resection by senior authors with meatal bone removal utilizing the UBA. Outcomes included hearing preservation, complications, and subjective impression of usability and degree of bone dissemination. Results: Fifty-five patients (42%women) were identified. The median age at diagnosis was 49, and median tumor size at surgery was 2.2 cm (range: 0.7–4.5 cm). 22% (n = 12) had tumors6 months of follow-up, the median postoperative House-Brackmann score was 1 (range: 1–3). Of patients undergoing hearing preservation surgery, 50% (n = 6) retained serviceable hearing. In all cases, the contralateral ear experienced no hearing loss. No additional complications related to use of the UBA such as jugular bulb injury or facial nerve trauma were encountered. Of patients with >6-month follow-up, 15% (n = 5/32) reported ongoing headache requiring medical treatment. The senior authors felt ease of dissection and perceived time requirement were similar to conventional meatal drilling, while degree of bone dissemination was less. Conclusion: UBA is safe and effective for accessing the IAC during VS surgery via the RS approach. Overall, there was a low complication rate and hearing preservation was achieved in half of patients with tumors <1.5 cm.