摘要
Abstract
BACKGROUND: The detective results of air conduction and bone conduction are different because of different auditory characteristics of these two transducers.OBJECTIVE: To discuss and compare the difference of auditory brain stem reaction(ABR) on air conduction(AC) and bone conduction(BC) for providing a gist in clinical application of bone-conducted auditory brain stem reaction.DESIGN: A self and inter control study was conducted.SETTING and PARTICIPANTS: The research was completed in a sound insulated and electric screened room of Department of Otolaryngology, Zhujiang Hospital, First Military Medical University. All subjects were a group of young people with normal hearing(31 male ears and 30 female ears) and an age from 19 to 23 years old(average 21.7 years old).INTERVENTIONS: American NicoIet spirit inducing electric potential instrument was introduced. The earphones for air conduction and bone conduction testing were TDH-39P and Radioear B-71 models, which accorded with GB/T 4851. 1 and GB/T 4854. 3 criteria after adjustment. The impedances of electrode were all less than 5 kΩ, and the impedance between electrodes was ≤4 kΩ. Short sound air-conducted and bone-conducted ABR for both ears were tested separately. The strength of stimulant started from 100 dB(nHL) (the maximum output of the machine) and decreased in turn by 20 dB(nHL), which was set as one grade, recorded twice. And 5 dB was chosen as one grade when closed to reactive threshold to induce the minimum repeatable sound strength as ABR threshold. Once ABR reactive threshold obtained, 60 dB(nHL) above threshold stimulant was operated to test air and bone conducted ABR and the latency of Ⅰ, Ⅲ, Ⅴ wave was recorded separately. Two groups of data obtained from same ear were self-paired for t test. The test results among normal young males and females were gone through unpaired t test.MAIN OUTCOME MEASURES: Threshold of air conduction and bone conduction for short sound in both males and females, latency and interval of each wave in air and bone conducted ABR.RESULTS: Under or below threshold, ABR wave of bone conduction was alike to that of air conduction, but with lower inducing rate. There was no significance in the ABR threshold for air and bone conducted short sound with normal auditory between normal young males and females( tAC= 0. 12,tBC = 1.08, P ＞ 0. 05) . The comparison between bone conducted short sound ABR and air conducted shout sound ABR suggested: the former was higher than the latter( t = 19.55, P ＜ 0. 01), with distinct positive correlation(r =0. 7740, P ＜ 0.01); the latencies of Ⅰ, Ⅲ, and Ⅴ wave of the former were all bigger than that of the latter under 60 dB(nHL) strength ( t = 10.62, P ＜ 0. 01), but there were no significant differences of Ⅰ-Ⅰ-Ⅱ, Ⅲ-Ⅴ and Ⅰ-Ⅴ intervals between the two(tAC = 1.45, tBC =0.68, P＞ 0. 05).CONCLUSION: There are certain limitations in the application of bone conducted ABR test. However, it still has merits in clinical application on some patients who are not suitable for air conducted ABR test.关键词
骨导/诱发电位/听觉/脑干/听阈分类
医药卫生
