Preliminary Outcomes Report for CO2 Laser Assisted Electric-Acoustic Cochlear Implantation

Report on the safety/efficacy of a novel, carbon dioxide (CO2) laser-assisted protocol for hearing-preservation cochlear implantation (HPCI) and electric-acoustic stimulation (EAS).

Retrospective case review.

Tertiary referral center.

Adult patients meeting established criteria for HPCI and EAS.

Therapeutic/rehabilitative. A standardized protocol used CO2 laser to achieve meticulous hemostasis and perform cochleostomy was evaluated.

Audiometric assessments included low-tone pure tone average (LtPTA), consonant-nucleus-consonant (CNC), and AzBio scores. Primary outcomes were low-tone hearing-preservation (LtHP) and EAS usage rates. Secondary outcomes included change in LtPTA, outcomes durability, and the rate/onset/presentation of delayed hearing loss (DHL). Subset analyses stratified data by presenting LtPTA and surgeon experience.

Forty-seven patients and 52 ears were included. Mean follow-up was 20.7 ± 12.6 months. When adjusted for preoperative LtPTA less than 60 dB, the LtHP rate was 77%. This was significantly better than for patients with LtPTA more than 60 dB (24%; p < 0.0001). Outcomes were highly durable. EAS usage was excellent in those with LtPTA less than 60 dB (100%). Nine patients developed DHL. Three additional patients (25%) were successfully salvaged via steroids. Both CNC and AzBio scores improved significantly (p < 0.0001) at definitive testing. Speech-hearing scores did not differ significantly between patients using/not using EAS. The complication rate was 3.8%; none were caused by the laser. Surgeon experience was associated with significantly better outcomes.

Use of a CO2 laser-assisted HPCI protocol was safe and effective. Outcomes were consistent with contemporary literature reporting. Patient selection and surgeon experience both significantly impacted outcomes.