Comparison of Slim Perimodiolar and Slim Straight Electrode Arrays in Pediatric Cochlear Implantation: A Radiologic,...

Electrode array design may influence auditory and language performance in pediatric cochlear implant (CI) recipients. Slim perimodiolar arrays, positioned closer to the modiolus, are hypothesized to provide more focused stimulation and lower current requirements. This study compares outcomes of slim perimodiolar (PM) and straight (ST) electrode arrays in children.

Retrospective cohort review.

Tertiary pediatric otolaryngology referral center.

Eighty-eight children underwent 122 implantations with slim PM (CI632/532, n = 65) or slim ST (CI422/522/622, n = 57) arrays between 2016 and 2023. For speech and language outcomes, 72 children were assessed globally at the patient level, including 68 sequential cases (first implanted side) and 4 simultaneous bilateral cases.

Auditory thresholds, impedances, T/C levels, and neural response telemetry (NRT) were analyzed postoperatively, at 6 and 12 months, speech and language performance (CAP and APCEI profile at 2 y). Angular depth of insertion (aDOI), basal insertion depth (BID), and modified intracochlear position index (mICPI) were derived from preoperative CT and postoperative radiographs.

PM arrays achieved significantly closer modiolar positioning (mICPI: 0.72 ± 0.07 vs 0.98 ± 0.06, P < 0.0001) with no difference in aDOI and BID, lower impedances at 1 and 12 months (P < 0.0001), lower NRT levels at 6 months (P = 0.001), and reduced energy requirements. In patient-level analyses, children implanted ≤3 years with PM arrays had higher APCEI (P = 0.006) and CAP scores (P < 0.03) compared with ST arrays. In children implanted >3 years, electrode type was not associated with outcomes, while age at implantation was the main determinant of language scores.

Slim PM arrays provide closer modiolar proximity, lower impedances, reduced energy consumption, with more consistent early hearing outcomes and better speech/language scores if implanted before 3 years of age. These findings support early implantation with slim perimodiolar arrays to optimize pediatric auditory and language performance.