Neural Response Telemetry Thresholds in Patients with Cochlear Nerve Canal Stenosis

• Published in: Otolaryngology-head and neck surgery Vol. 153; no. 3; p. 447
• Main Authors: Han, Shuguang, Wang, Line, Zhang, Daoxing, Peng, Kevin
• Format: Journal Article
• Language: English
• Published: England 01.09.2015
• Subjects: Auditory Threshold - physiology; Child; Child, Preschool; Cochlear Implantation; Cochlear Nerve - diagnostic imaging; Cochlear Nerve - physiopathology; Constriction, Pathologic; Female; Hearing Loss, Sensorineural - diagnostic imaging; Hearing Loss, Sensorineural - physiopathology; Hearing Loss, Sensorineural - surgery; Hearing Tests; Humans; Infant; Male; Telemetry; Temporal Bone - diagnostic imaging; Tomography, X-Ray Computed; Treatment Outcome; cochlear nerve deficiency; neural response telemetry; cochlear nerve canal stenosis; cochlear implantation
• ISSN: 1097-6817
• DOI: 10.1177/0194599815592365

To explore neural response telemetry (NRT) thresholds in patients with stenotic versus normal cochlear nerve canals. Case series with chart review. Tertiary referral center. Thirty pediatric patients with profound sensorineural hearing loss in at least 1 ear and no benefit from amplification underwent computed tomography imaging of the temporal bones. They were divided into 3 groups according to the diameter of the cochlear nerve canal: group A, <1.5 mm; group B, 1.5 to 1.7 mm; group C, 1.8 to 2.1 mm. All patients underwent cochlear implantation with full insertion of all electrodes. NRT was performed both intraoperatively and 6 months postoperatively in all patients; thresholds of electrodes 1, 11, and 22 were compared. Per analysis of variance, intraoperative and 6-month postoperative NRT thresholds were both significantly different among groups A, B, and C at electrodes 1 and 22 but not at electrode 11. On intergroup analysis, group A showed statistically higher thresholds than those of groups B and C; however, no difference was found between groups B and C. Cochlear nerve canal stenosis, defined as a canal diameter <1.5 mm, is associated with significantly increased NRT thresholds, which may play a role in postimplant performance.