Thermal Analysis of an Ultrasonic Aspirator Micro Claw Tool Compared With Standard High-Speed Drilling During Internal Auditory Canal Opening in a Cadaveric Model.

Abstract

The ultrasonic aspirator micro claw tool (UAmCT) can be used to remove the bone of the internal auditory canal (IAC) during vestibular schwannoma resection via the retrosigmoid approach (RSA) without the risk of a spinning drill shaft. However, the thermal profile of the UAmCT during IAC removal has not been reported. To compare the thermal profile of the UAmCT during access of the IAC to that of a conventional high-speed drill (HSD) and to present an illustrative case of this application. IAC opening via RSA was performed in 5 embalmed cadaveric specimens using the UAmCT with 3, 8, and 15 mL/min irrigation on the left and the HSD at 75 000 revolutions per minute and 0%, 14%, and 22% irrigation on the right. Peak bone surface temperatures were measured 4 times in 20-second intervals, and statistical analyses were performed using SPSS software. An illustrative case of a vestibular schwannoma resected via an RSA using the UAmCT to access the IAC is presented. The IAC was opened in all 5 specimens using both the UAmCT and HSD without complication. The mean peak bone surface temperatures were significantly lower with the UAmCT compared with the HSD ( P < .001). The UAmCT did not meaningfully prolong the operating time in the illustrative case, and the IAC was accessed without complication. The UAmCT may be a safe and effective alternative to HSD for IAC opening during vestibular schwannoma resection via the RSA. Larger studies under clinical conditions are required to further validate these findings.