Hearing Preservation Outcomes Using a Precurved Electrode Array Inserted With an External Sheath

• Published in: Otology & neurotology Vol. 41; no. 1; p. 33
• Main Authors: Nassiri, Ashley M, Yawn, Robert J, Holder, Jourdan T, Dwyer, Robert T, O'Malley, Matthew R, Bennett, Marc L, Labadie, Robert F, Rivas, Alejandro
• Format: Journal Article
• Language: English
• Published: United States 01.01.2020
• Subjects: Adult; Cochlear Implantation - instrumentation; Cochlear Implantation - methods; Cochlear Implants; Female; Hearing - physiology; Humans; Male; Middle Aged; Retrospective Studies; Treatment Outcome
• ISSN: 1537-4505
• DOI: 10.1097/MAO.0000000000002426

Describe audiologic outcomes in hearing preservation cochlear implantation (CI) using a precurved electrode array inserted using an external sheath and evaluate association of electrode positioning and preservation of residual hearing. Retrospective review. Tertiary otologic center. Twenty-four adult patients who underwent hearing preservation CI with precurved electrode array. CI, intraoperative computed tomography (CT) OUTCOME MEASURES:: Audiologic measures (consonant-nucleus-consonant [CNC] words, AzBio sentences, low-frequency pure tone averages [LFPTA]) and electrode location (scalar location, electrode-to-modiolus distance ((Equation is included in full-text article.)), angular insertion depth). Twenty-four adults with less than 80 dB LFPTA with a precurved electrode array inserted using an external sheath; 16 underwent intraoperative CT. LFPTA was 58.5 dB HL preoperatively, with a 17.3 dB threshold shift at CI activation (p = 0.005). CNC word scores improved from 6% preoperatively to 64% at 6 months postoperatively (p < 0.0001). There was one scalar translocation and no tip fold-overs. The average angular insertion depth was 388.2 degrees, and the average (Equation is included in full-text article.)across all electrodes was 0.36 mm. Multivariate regression revealed a significant correlation between CNC scores at 6 months and angular insertion depth (p = 0.0122; r = 0.45, adjusted r = 0.35). Change in LFPTA was not significantly associated with angular insertion depth or (Equation is included in full-text article.). A low rate of translocation allows a precurved electrode array inserted using an external sheath to maintain hearing preservation rates comparable to straight electrode arrays. With scala tympani insertion, angular insertion depth is a positive marker of improved speech performance postoperatively but may be a confounder variable based on individual cochlear size.