Shujiro B Minami1,2, Nobuko Yamamoto2, Makoto Hosoya3, Chieko Enomoto1, Hidetoshi Kato1, Kimitaka Kaga2. 1. Department of Otolaryngology, National Hospital Organization Tokyo Medical Center, Tokyo, Japan. 2. Division of Hearing and Balance Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan. 3. Department of Otolaryngology, Head and Neck Surgery, School of Medicine, Keio University, Tokyo, Japan.
Abstract
OBJECTIVE: To propose a simple grading of inner ear malformation (IEM) and investigate intracochlear electrical auditory brainstem response (EABR) and outcomes for hearing in terms of the novel grading system. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Sixty patients with IEMs who received cochlear implants. INTERVENTION: Grading according to observation of modiolus deficiency and/or internal auditory canal (IAC) cochlear nerve deficiency (CND). MAIN OUTCOME MEASURE: Intracochlear EABR and categories of auditory performance (CAP) scores were assessed; children in school were categorized according to the type of school attended. RESULTS: Among 60 patients, 38% were classified as Grade I (modiolus present + normal cochlear nerve), 22% as grade II (modiolus deficiency + normal cochlear nerve), 33% as grade III (modiolus present + IAC CND), and 7% as grade IV (modiolus deficiency + IAC CND). During the operation, 93% of Grade I, 36% of Grade II, 23% of Grade III, and 50% of Grade IV patients showed typical EABR waves. CAP scores of 4 or more were obtained from 91% of Grade I, 62% of Grade II, 35% of Grade III, and 25% of Grade IV. Whereas none of children in Grades III and IV entered main stream school, 55% of Grade I and 25% of Grade II entered mainstream schools. CONCLUSIONS: Outcomes of hearing with cochlear implantations in IEM children depend on the severity of IEM and IAC CND. Our novel grading of IEM is simple and can be useful for understanding the severity of IEM.
OBJECTIVE: To propose a simple grading of inner ear malformation (IEM) and investigate intracochlear electrical auditory brainstem response (EABR) and outcomes for hearing in terms of the novel grading system. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Sixty patients with IEMs who received cochlear implants. INTERVENTION: Grading according to observation of modiolus deficiency and/or internal auditory canal (IAC) cochlear nerve deficiency (CND). MAIN OUTCOME MEASURE: Intracochlear EABR and categories of auditory performance (CAP) scores were assessed; children in school were categorized according to the type of school attended. RESULTS: Among 60 patients, 38% were classified as Grade I (modiolus present + normal cochlear nerve), 22% as grade II (modiolus deficiency + normal cochlear nerve), 33% as grade III (modiolus present + IAC CND), and 7% as grade IV (modiolus deficiency + IAC CND). During the operation, 93% of Grade I, 36% of Grade II, 23% of Grade III, and 50% of Grade IV patients showed typical EABR waves. CAP scores of 4 or more were obtained from 91% of Grade I, 62% of Grade II, 35% of Grade III, and 25% of Grade IV. Whereas none of children in Grades III and IV entered main stream school, 55% of Grade I and 25% of Grade II entered mainstream schools. CONCLUSIONS: Outcomes of hearing with cochlear implantations in IEM children depend on the severity of IEM and IAC CND. Our novel grading of IEM is simple and can be useful for understanding the severity of IEM.
Authors: Anandhan Dhanasingh; Daniel Erpenbeck; Masoud Zoka Assadi; Úna Doyle; Peter Roland; Abdulrahman Hagr; Vincent Van Rompaey; Paul Van de Heyning Journal: Sci Rep Date: 2021-10-21 Impact factor: 4.379