Robotic-Assisted Electrode Array Insertion Improves Rates of Hearing Preservation.

OBJECTIVE(S): Robotic-assisted electrode array (EA) insertion is a promising technique that may enhance hearing preservation in cochlear implant (CI) surgery. The purpose of our study is to understand the extent to which robotic-assisted EA insertion improves hearing preservation.

METHODS

Twenty-four adult patients underwent CI surgery with manual EA insertion and 27 adult patients underwent CI surgery with robotic-assisted EA insertion using the iotaSOFT system. The EAs used included the Flex 20/24/26. The primary outcome variable was low frequency pure-tone average (LFPTA), defined as mean audiometric threshold at 125, 250, and 500 Hz. This was measured preoperatively, at initial activation (within 4 weeks of surgery), and subsequently at 2 weeks, 3 months, 6 months, and 1 year. Functional acoustic hearing was defined as LFPTA < 80 dB HL.

RESULTS

Seventeen out of 24 patients (71%) in the manual insertion group and 23 out of 27 patients (85%) in the robotic-assisted EA insertion group had preserved functional acoustic hearing (< 80 dB HL) up till 1 year (Fisher's exact test (two-tailed) is not statistically significant, p = 0.31). The number needed to treat with robotic-assisted EA insertion to prevent one additional negative outcome of loss of functional acoustic hearing would be 7 (1/0.14).

CONCLUSION

Robotic-assisted EA insertion is associated with improved hearing preservation over 1 year compared with manual insertion. Hearing preservation leads to improved outcomes and therefore every effort should be made to preserve the delicate structure and function of the cochlea during EA insertion. Robotic-assisted EA insertion advances that objective.

LEVEL OF EVIDENCE: III (cohort study).