Analysis of auditory brainstem response to narrow band level specific CE-Chirp in infants

Abstract

Auditory brainstem response (ABR) is one of the audiological tests used for hearing threshold estimation in infants, especially those under six months of age. The conventional ABR test is considered a time-consuming procedure because of the limitation in the current acoustic stimuli (e.g., click and tone burst) and ABR stimulus parameters that resulted in an extension of the test session. Hence, the present study proposes the latest acoustic stimulus, namely narrow band level specific (NB LS) CE- Chirp and F-test multiple points (Fmp), to address this issue. The combination of frequency specifics stimulus and Fmp is foreseen to lessen the ABR assessment period, reduce the number of patients lost to follow up due to miscellaneous factors (i.e., financial and parents’ limited annual leave) and decrease the age of audiological diagnosis for early aural rehabilitation management to promote good health, well-being, and quality education opportunities for all ages; as defined in Sustainable Development Goal (SDG) of United Nations Educational, Scientific and Cultural Organization (UNESCO). This study aimed to investigate the ABR findings from NB LS CE-Chirp stimulus in newborn infants in comparison with the ABR elicited from tone burst stimulus in terms of amplitude, absolute latency, hearing threshold estimation, and test time based on two stopping criteria (i.e., signal-to-noise ratio (SNR) objective algorithm; Fmp and visual detection). The current study conducted ABR assessment in 50 infants (27 males and 23 females) aged below 6 months old with normal middle ear conditions and passed the neonatal hearing screening. The ABR using NB LS CE-Chirp and tone burst stimuli were tested at three specific frequencies of 500, 1000, and 4000 Hz at 70 and 40 dBnHL using a 33.33 Hz stimulus rate. The result indicated that the ABR elicited from NB LS CE-Chirp and tone burst stimuli showed similar wave V amplitude across the frequencies and intensity range tested except for 1000 Hz at 70 dBnHL. In contrast, the ABR to NB LS CE-Chirp wave V amplitude was slightly larger than the ABR to tone burst at 40 dBnHL in all frequencies tested. The NB LS CE Chirp has significantly shorter offset absolute latencies and lower hearing threshold estimation than ABR in tone burst stimulus. The ABR to NB LS CE-Chirp also has significantly shortest test time in identifying wave V using Fmp ≥ 3.1 and visual detection compared to ABR to tone burst. In conclusion, ABR to NB LS CE-Chirp with SNR objective algorithm detection has the potential for infants’ hearing assessment application as it elicits the shortest test time and lower hearing threshold estimations for audiogram prediction. However, the quality of the recording between the ABR to NB LS CE- Chirps was marginal compared to the ABR elicited from tone burst stimulus.