▲Professor Hong Ju Park is examining a hearing-impaired pediatric patient

A research team, led by Professor Hong Ju Park from the Department of Otolaryngology-Head and Neck Surgery at Asan Medical Center, has recently published research suggesting that cochlear implantation outcomes can be predicted based on the condition of the patient's auditory nerve.

The team conducted a follow-up study spanning over 7 years on the auditory development of 42 pediatric patients (49 ears) who underwent cochlear implantation between 1994 and 2013. These patients were diagnosed with severe hearing loss attributed to Mondini dysplasia, a condition characterized by the incomplete partition of the cochlea.

Analysis of ear CT images revealed that four ears exhibited narrow bony cochlear nerve canals (BCNC), which serve as pathways for auditory nerve bundles. These patients experienced poorer cochlear implantation outcomes due to their inferior auditory functions compared to those with normal BCNC. The Word Recognition Score (WRS), a test assessing speech discrimination ability, indicated that patients with narrow BCNC had an average accuracy of 58%, while those with normal BCNC achieved 79%. Among 86 pediatric patients with normal inner ears who still underwent cochlear implantation due to hearing impairments, the average accuracy was 77%. Moreover, a significant correlation was established between the maximum diameter of the cochlear nerve and auditory function after cochlear implantation. Patients with thicker cochlear nerves on MRI demonstrated higher speech discrimination accuracy.

In light of these findings, the research team concluded that even in cases of inner ear anomalies, the auditory abilities of patients can be enhanced to a level comparable to those with normal inner ears who undergo cochlear implantation. Professor Hong Ju Park stated, “I hope that this research will assist many hearing-impaired patients in making informed decisions regarding surgery.”

The research results were recently published in 'Otology & Neurotology,' the official academic publication of the American Otological Society.