Auditory functions in children at schools for the deaf

Objective: To evaluate auditory functions in children at schools for the deaf in Turkey. Design: A total of 218 children who were attending the school for deaf children were involved in the study. Familial and medical histories were obtained, and otoscopic examinations were performed. Immittance audiometry, acoustic reflex testing, pure tone audiometry, otoacoustic emission and auditory brain stem response tests were performed. Results: The mean age of identification of hearing loss was 48 months. Impacted wax was the most common otoscopic finding that was seen in 49 (22.47%) of children. Nontype-A tympanograms were found in 18 (8.25%) of children. One-hundred-eighty-nine (86.69%) children had profound hearing loss, and 29 (10.3%) had severe hearing loss on pure tone audiometry. On auditory brain stem response testing, 192 (88.07%) children hod profound hearing loss, and 26 (11.41%) had severe hearing loss. Only one child had auditory neuropathy/dys-synchrony, as his otoacoustic emission results were normal without synchronous auditory brain stem responses. The hearing threshold levels were found > 105 dB in 28 children only with pure tone audiometry. Conclusion: Early auditory screening is necessary to identify the children at risk. All hearing disorders cannot be detected by subjective or objective audiometric tests only. Pure tone audiometry still has a role in determining hearing threshold levels. The audiological research directions should be directed towards routine pure tone audiometry, otoacaustic emission and auditory brain stem response assessment for all hearing impaired children to enable an successful treatment.