Role of electrically evoked auditory brainstem response in cochlear implantation of children with inner ear malformations.
OBJECTIVE
To evaluate the usefulness of promontory electric auditory brainstem response (EABR) testing in children with inner ear malformations before cochlear implantation indicated by postoperative speech performance.


METHODS
Retrospective analysis.


METHODS
Tertiary academic cochlear implant center.


METHODS
Forty-three children with congenital inner ear malformations, of which 39 received a cochlear implant. Age at implant ranged from 12 months to 13 years. Patients were categorized into 3 groups based on the type of malformations. Groups 1 and 2 involved malformations of the cochlea and/or vestibular organ. Group 3 consisted of children with narrow internal auditory canal.


METHODS
Preoperative EABR testing with threshold, Wave V amplitude, and latency determination.


METHODS
Postoperative speech perception performance was measured using Glendonald Auditory Speech Perception Tests for words and sentences, Northwestern University-Children's Perception of Speech test, and minimal pairs test. Patients were further categorized into a speech perception category based on these test results.


RESULTS
Mean values for EABR threshold, Wave V amplitude, and latency for Group 1 (11 patients) were 485 microA, 0.21 microV, and 4.51 milliseconds, respectively. Mean values for Group 2 (20 patients) were 556 microA, 0.26 microV, and 4.45 milliseconds, respectively. Mean values for Group 3 (8 patients) were 500 microA, 0.11 microV, and 4.65 milliseconds, respectively. Open-set sentence recognition was possible in 73% in Group 1, 30% in Group 2, and 38% in Group 3 by 36 months after implant activation. Patients with lower preoperative EABR threshold (<600 microA) had better postoperative speech performance (p < 0.05). Larger Wave V amplitude and shorter latency were associated with better speech performance.


CONCLUSIONS
Preoperative EABR is useful in determining cochlear implant candidacy in children with inner ear malformations. Results of this study indicate that the EABR accurately predicts outcome when cochlear implant efficacy is uncertain.
Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, USA. hkim@nyee.edu
Ana H
AH
Kim
Paul R
PR
Kileny
H Alexander
HA
Arts
Hussam K
HK
El-Kashlan
Steven A
SA
Telian
Terry A
TA
Zwolan
D000293:Adolescent; D001309:Auditory Threshold / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D003051:Cochlea / Q000002:abnormalities* / Q000601:surgery*; D019929:Cochlear Implantation; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D013063:Speech Discrimination Tests