[Application of auditory brainstem response to different types of hearing loss in infants]

Objective:The aim of this study is to analyze the variation characteristics of ABR wave latency and wave interval in different functional states of middle ear and different hearing levels, and to explore the value of ABR detection method in hearing assessment of infants. Methods:A total of 670 children were enrolled in the Pediatric Hearing Diagnosis and Treatment Center of the Department of Otolaryngology head and Neck Surgery, Beijing Children's Hospital, Capital Medical University from May 2020 to April 2021. According to the hearing test results, they were divided into group A normal group（632 ears）. Group B consisted of normal middle ear function and abnormal hearing（157 ears）, further divided into mild hearing loss subgroup（49 ears）, moderate hearing loss subgroup（47 ears） and severe to very severe hearing loss subgroup（61 ears）. Group C was a group with abnormal middle ear function（551 ears）, which was further divided into normal hearing subgroup（307 ears）, mild hearing loss subgroup（110 ears）, moderate hearing loss subgroup（107 ears） and severe to very severe hearing loss subgroup（27 ears）. The differences of Ⅰ, Ⅲ, Ⅴ Wave Latency, Ⅰ-Ⅲ, Ⅰ-Ⅴ wave interval between subgroups B and C and Group A, and between subgroups B and C were analyzed. Results:When the stimulus intensity was 80 dB nHL, there was no significant difference in ABR latency and wave interval between group B and group A, and there was no significant difference between group B and group A（P>0.05）, nor between the two groups（P>0.05）. In the subgroup of severe to very severe hearing loss, some ABRⅠ, Ⅲ and Ⅴwaves could not be elicited, only Ⅲ and Ⅴ waves were elicited from 4 ears and Ⅴ waves were elicited from 7 ears. The mean latency of 11 ear Ⅲ and Ⅴ waves was （5.20±0.44） ms and （6.80±0.75） ms, respectively, which was longer than that of mild and moderate hearing loss subgroups. Compared with group A, the latency of normal hearing subgroup in group C was significantly prolonged only for wave Ⅰ, and the latency of wave I, Ⅲ and Ⅴin other subgroups was significantly prolonged（P<0.01）. In terms of Ⅰ-Ⅲ and Ⅰ-Ⅴ wave intervals, there was no significant difference between group C and group A in normal hearing subgroup and mild loss subgroup. The subgroup of moderate hearing loss and the subgroup of severe to very severe hearing loss were significantly shorter than the group A（P<0.01）. Compared with the normal group, the latency of Ⅰ, Ⅲ and Ⅴ waves in group C were significantly longer（P<0.01）. The latency of wave Ⅰ, in the moderate hearing loss group was significantly longer than that in the mild hearing loss group（P<0.001）. The latency of each wave in severe to very severe hearing loss subgroup was significantly longer than that in mild and moderate hearing loss subgroup（P<0.001）. There was no difference between mild hearing loss subgroup and normal hearing subgroup（P>0.05）. The subgroup of moderate hearing loss and severe to very severe hearing loss were significantly shorter than the subgroup of normal hearing and the subgroup of mild hearing loss, and there was a significant difference between the two groups（P<0.01）. Conclusion:In sensorineural hearing loss, mild and moderate hearing loss had no significant effect on the latency and interwave period of ABR. The latency of each wave in severe to very severe hearing loss cannot be elicited normally or only Ⅲ and Ⅴ waves can be elicited, and it is significantly prolonged. The latency of ABR Ⅰwave was significantly prolonged when middle ear function was abnormal. The latency of each wave was significantly prolonged when middle ear function was abnormal and hearing was abnormal. When hearing loss reaches a certain degree, the interwave period is shortened significantly. Therefore, for mild to moderate hearing loss, the prolonged latency of ABRⅠ wave is of certain value for the qualitative diagnosis of hearing loss, and the prolonged latency of ABR Ⅰwave is of significance for judging middle ear dysfunction in infants.