Evaluating Auditory Pathway by Electrical Auditory Middle Latency Response and Postoperative Hearing Rehabilitation

Preoperative EABR evaluation of auditory pathway integrity in patients with different etiology and postoperative effect estimation

OBJECTIVES

To evaluate the effect of electrical auditory brainstem response (EABR) on the integrity evaluation of auditory pathway and the prediction of postoperative effect of cochlear implantation in patients with different etiology of hearing loss.

METHODS

A total of 580 patients with neuropathic deafness who underwent cochlear implantation surgery from August 2011 to December 2020 were selected for EABR test. The preoperative EABR waveform was analyzed, and parameters such as V wave amplitude, threshold, latency and interval of each wave, and slope of V wave I/O curve were measured. Neural response telemetry (NRT) test was performed during MAP 1 month after operation, and C and T values of the machine were recorded.

RESULTS

The total EABR extraction rate was 98.45% among 580 patients, including 100% for the normal structure group and enlarged vestibular aqueduct group (LVAS), 92.44% for other malformed group. The average threshold of V wave in patients with normal cochlear structure was significantly better than the malformation groups (p < 0.05). The total extraction rate of NRT was 78.62%, including 99.72% in the group with normal structure, 95.65% in the LVAS group, 1.85-88.24% in the group with other malformations, and 0% in the cochlear ossification group. The correlation analysis showed a statistically significant correlation between the average preoperative EABR threshold and the C value of NRT.

CONCLUSIONS

Preoperative EABR could evaluate the integrity of auditory conduction pathway of patients with cochlear implantation and predict the postoperative hearing rehabilitation effect.

Evaluation of auditory pathway by EABR before cochlear implantation and the postoperative effect analysis

OBJECTIVE

To investigate the evaluation value of electrically evoked auditory brainstem response (EABR) monitoring before cochlear implantation in patients with cochlear nerve defects (CND).

METHODS

A total of 54 patients with cochlear nerve defects who underwent cochlear implantation in our hospital from 2011 to 2018 were selected as the CND group, and 20 patients with normal cochlear implantation were selected as the control group. The preoperative audiological characteristics, EABR characteristics and follow-up neural response telemetry results of the two groups were retrospectively analysed, and the preoperative EABR threshold and initiation C value were subjected to linear regression and correlation analysis.

RESULTS

The EABR waveform of the CND group was significantly different from the control group in terms of average wave V threshold, average dynamic range and V-wave I/O curve slope (P < 0.05). Average C value and dynamic range had a statistically significant difference from the control group (P < 0.05). Statistically significant positive correlations were found between the EABR threshold and C value, wave V I/O slope and postoperative category of auditory perception (P < 0.05).

CONCLUSIONS

The EABR test can be used to evaluate the auditory pathway function before cochlear implantation and its postoperative effect in patients with CND.

Electrophysiological differences in distinct hearing threshold level individuals with and without tinnitus distress

Tinnitus is the perception of sound when no actual external noise is present. Tinnitus is highly prevalent, with more than 1 in 7 adults in the EU having tinnitus, and it causes negative effects on quality of life for many individuals. However, there is currently no cure for tinnitus and its pathophysiology and genesis are unknown. Auditory evoked potentials (AEPs) provide a non-invasive means by which the electrical signals evoked by the brain can be recorded, and constitute a useful indicator for the evaluation of auditory disorders such as tinnitus and hearing loss. The present study analyzed a total of 98 auditory middle evoked potential (AMLR) waveforms, a subtype of AEPs, from 49 participants with subjective tinnitus, attempting to identify differences in AMLR parameters between sufferers with and without tinnitus distress. The waveforms were divided into three categories according to the ear's hearing level, and comparisons were made between sufferers in the same hearing level category. The results of the analysis indicated some statistically significant differences in AMLR latencies and amplitudes between the compared groups. Clinical Relevance- Identification of the electro-physiological profile of subjective tinnitus sufferers based on the distress manifested by tinnitus using AMLRs.