An Analysis Of The Features Of Acoustically Evoked Short Latency Negative Response In Patients With Large Vestibular Aqueduct Syndrome

Objective: to explore the features of ASNR in patients with LVAS and to provide scientific basis for the early diagnosis of patients.Methods: Our retrospective studies found that a total of 1611 cases(2798ears)were diagnosed severe or above hearing loss by auditory brainstem response(ABR)test in our hospital during a period from Jan.,2017 to Dec.,2019,out of these 1611 cases,272 cases(374 ears)appeared ANSR,but just 181cases(245 ears)with ASNR received the ear image examinations.Based on the results of those ear image examinations,the subjects 181 cases(245 ears)were divided into LVAS group and non-LVAS group to compare the relations of sex,age,ear sides as well as that of ASNR threshold,amplitude and latency.Then the LVAS group,according to the results of their ear image examinations,was further divided into a simple LVAS group and a combined LVAS group(with other inner ear malformations)to compare the relations of ASNR threshold,amplitude and latency.Results:1.The induced rate of ASNR in ears with severe hearing loss was about 13.37%(374/2798 ears).2.Those cases shared some common characteristics: out of 181 patients(245 ears),males added up to 102 cases while females accounted for 79 cases,at an age range from 2 months old to 23 years old,and the median age was 41 months.101 patients(145 ears)out of 181 cases(245 ears)were diagnosed with LVAS and 80 patients(100 ears)with non-LVAS,which accounted for a positive rate of LVAS 59.18%.The number of ears from the simple LVAS group took up 37.77% and that from the combined LVAS group(with other inner ear malformations)took up 21.63%.The LVAS group was compared with the non-LVAS group.The results showed sex and age comparisons were all statistically meaningless(P > 0.05).However,the comparisons of ASNR ear sides were statistically significant(P<0.05).Among them,the positive rate of LVAS in double-ear ASNR patients was higher than the left-ear ASNR patients,and the variations were found statistically meaningful(P < 0.05).The rest of the comparisons of ear side were all statistically meaningless(P > 0.05).The comparisons of ASNR patients in threshold,amplitude and latency between the two groups were statistically meaningful(P < 0.05).Compared to non-LVAS patients,LVAS patients have lower threshold,higher amplitude and shorter latency of ASNR.3.Comparisons were also made between the simple LVAS group and the combined LVAS group(with other inner ear malformations).The results indicated that the variation of ASNR amplitude was statistically meaningful(P<0.05),but the variations of ASNR threshold and latency between the two groups were not statistically meaningful(P>0.05).Conclusion: 1.Among the ears diagnosed with severe hearing loss,the induced rate of ASNR was about 13.37%.2.Among the ears diagnosed with severe hearing loss with ASNR:(1)The positive rate of LVAS was 59.18%,of which the simple LVAS ears accounted for 37.55% and the combined LVAS ears(with other inner ear malformations)accounted for 21.63%;(2)Test results showed the positive rate of LVAS had no relations to the sex and age of patients,but it had a closer relation to the ear sides,and the positive rate of LVAS in double-ear ASNR patients was higher.(3)The features of ASNR:(1)Compared with non-LVAS ears,LVAS ears appeared lower threshold,higher amplitude and shorter latency of ASNR;(2)Compared with the combined LVAS ears(with other inner ear malformations),the ears from the simple LVAS group appeared higher amplitude of ASNR,but there was no difference in threshold and latency of ASNR between the two groups.