S106. Normative data of auditory brainstem response in nepalese population

Introduction Auditory Brainstem Response (ABR) is the potential recorded from the ear and the scalp in response to a brief auditory stimulation. It is usually helpful in localizing the lesions in the brainstem. It is useful in diagnosing diseases like intrinsic brainstem tumor, multiple sclerosis, coma, brain death and strokes affecting the brainstem. It can also be used to assess the integrity of auditory pathway. Methods The study was conducted on 30 consenting healthy adult subjects. Auditory Brainstem Response (ABR) was recorded at 60 dB sound intensity. Mean and standard deviation were determined for waveforms I, II, III, IV, and V and interpeak intervals of waveforms I–III, III–V, and I–V. Student t -test was used for statistical analysis. Results In ABR, wave latencies and interpeak latencies were measured. Latencies of wave I [1.85 ± 0.23 ms], wave II [2.99 ± 0.27 ms], wave III [4.21 ± 0.41 ms], wave IV [5.38 ± 0.42 ms], wave V [6.48 ± 0.53 ms] and interpeak latencies I–III [2.35 ± 0.4 ms], III–V [2.28 ± 0.54 ms] and I–V [4.63 ± 0.54 ms]. Conclusion ABR parameters shows variation in values depending upon age, maturation of auditory pathway, environmental factors, laboratory setup. Hence it is concluded that each laboratory should have its own normative data which can be used as a baseline data for screening of patients with hearing loss.