Acoustic immittance measures and middle ear assessment: Current practice by South African audiologists

Background: Limited research exists regarding South African audiologists’ practice with acoustic immittance. This study was part of a bigger study titled ‘Wideband acoustic immittance in adults living with human immunodeficiency virus’.Objectives: The purpose of the study was to explore current practice of South African audiologists regarding acoustic immittance measures, and to explore their perceived knowledge and views on acoustic immittance advancements.Method: A quantitative survey with a cross sectional design was employed. An electronic questionnaire was distributed to participants via professional associations of audiologists. Data was analysed through descriptive and inferential statistics.Results: Most audiologists worked in private practice and conducted tympanometry with 226Hz probe tone and ipsilateral acoustic reflexes. There was no association between clinical setting, levels of qualification, and the use of tympanometry. None of the participants included multifrequency and multicomponent tympanometry (MFT) and/or wideband acoustic immittance (WAI) in their test battery. Most of the participants were not familiar with MFT and WAI. Familiarity with MFT and WAI were only associated with the level of qualification. Limited training and lack of equipment were major barriers to conducting some of the acoustic immittance measures. Most participants believed that they would include MFT and/or WAI in their test battery if they had access to the equipment.Conclusion: Current findings raise training and clinical implications for the South African audiologists, including training institutions. These findings provide motivation for strategic resource allocation, planning and distribution of audiology clinics in the country if positive preventive audiology outcomes are to be achieved.

Effect of age on acoustic reflex thresholds in neonates and infants with normal hearing

<p><strong>Background:</strong> High frequency (1000 Hz) probe tone holds substantial promise for carrying out acoustic reflexes in neonates and infants. A limited number of studies indicates that acoustic reflex thresholds (ART) also change significantly with age as the newborn hearing system matures. However, there is a need for obtaining more data before using it in a clinical population. The aim was to investigate effect of age of infants on ARTs. Effect of activator signal was also explored. <strong></strong></p><p><strong>Methods:</strong> ARTs were monitored using a 1 kHz probe tone for the 500 Hz, 1 kHz, 2 kHz, and 4 kHz pure tone activators in neonates and infants in the age range of 6 to 8 weeks were analysed.</p><p><strong>Results</strong>: The mean ARTs for neonates were lower compared to infants. Results of repeated measure ANOVA showed that there was a statistically significant age effect. Also, ARTs for high frequency activator signals were significantly higher than the ARTs for low frequency signals.</p><p><strong>Conclusions:</strong> The acoustic reflexes can be elicited for 500, 1000, 2000, and 4000 Hz when monitored using a 1000 Hz probe tone. There is an effect of age and activator signal on the acoustic reflex threshold. The data obtained in the present study can serve as normative for 0-1-week neonates and 6-8-weeks infants.</p>

Acoustic Reflexes in Aural Atresia Patients: Evidence of an Intact Efferent System?

Objective: To record crossed acoustic reflex thresholds (xART’s) postoperatively from patients after surgical repair of unilateral congenital aural atresia (CAA). To seek explanations for when xARTs can and cannot be recorded. We hope to understand the implications for this central auditory reflex despite early afferent deprivation. Methods: Patients who underwent surgery to correct unilateral CAA at a tertiary academic medical were prospectively enrolled to evaluate for the presence of xART. Preoperative ARTs in the normal (non-atretic) ear, and postoperative ipsilateral ARTs (stimulus in the normal ear) and contralateral ARTs (stimulus in the newly reconstructed atretic ear; record in the normal ear) were measured at 500, 1000, and 2000 Hz. Results: Four of 11 patients with normal ipsilateral reflex thresholds preoperatively demonstrated crossed acoustic reflexes postoperatively (stimulus in reconstructed ear; record from normal ear). Four other patients demonstrated normal ipsilateral thresholds preoperatively but did not have crossed reflexes postoperatively. No reflexes (pre- or postoperatively) could be recorded in 3 patients. Crossed reflex threshold is significantly correlated with the postoperative audiometric threshold. There was no correlation between ipsilateral and contralateral reflex thresholds. Conclusion: Crossed acoustic reflexes can be recorded from some but not all postoperative atresia patients, and the thresholds for those reflexes correlate with the postoperative pure tone threshold. The presence of acoustic reflexes implies an intact CN VIII-to-opposite CN VII central reflex arc despite early unilateral sound deprivation.

Sensitivity of High-Resolution Computed Tomography in Otosclerosis Patients undergoing Primary Stapedotomy

Objective: To determine the incidence of abnormal otospongiotic or otosclerotic findings on high-resolution computed tomography (HRCT) as read by local radiologists in patients with surgically-confirmed otosclerosis. Study design: Retrospective chart review. Setting: Tertiary-referral private otology-neurotology practice. Patients: Adults (>18 years old) with surgically-confirmed otosclerosis between 2012 and 2017 with a HRCT performed preoperatively. Intervention: Preoperative HRCT then stapedotomy. Main outcome measures: Positive identification and location of radiographic otosclerosis as reported by the local radiologist. We then correlated the CT with surgical location as documented at time of surgery. Audiometry, demographic data, intraoperative findings, and surgical technique were secondarily reviewed. Results: Of the 708 stapes surgeries were performed during the study time frame. Preoperative HRCT scans were available for 68 primary stapedotomy surgeries performed in 54 patients. Otosclerosis was reported in 20/68 (29.4%). Following a negative report by the local radiologist, a re-review by the surgeon and/or collaborating neuroradiologist confirmed otosclerosis in 12/48 additional cases (25.0%). There was an overall sensitivity of 47.1%. Intraoperatively, cases with negative reads tended to have more limited localization at the ligament (8.7%) or anterior crus (39.1%), compared with positive reads, which demonstrated more extensive involvement, with bipolar foci (30.0%) or diffuse footplate manifestations (20.0%) more common. Acoustic reflexes were characteristically absent. Conclusions: While HRCT may aid in the diagnosis of otosclerosis and rule out concomitant pathology in certain cases of clinical uncertainty or unexplained symptoms, its sensitivity for otosclerosis remains low. HRCT should not be relied upon to diagnose routine fenestral otosclerosis.

Acquired auditory neuropathy spectrum disorder after malaria treated with quinine

Auditory neuropathy spectrum disorder (ANSD) can cause significant hearing impairment; it occurs when there is intact outer hair cell function in the inner ear, with a dyssynchronous neural response, thought to be due to dysfunction of the inner hair cells (IHCs), the synapse of the IHCs and the auditory nerve, or of the auditory nerve itself. This case report describes the onset of ANSD in a Malawian child after severe malaria treated with quinine. Diagnosis of ANSD was made by confirming the presence of otoacoustic emissions, together with the absence of auditory brainstem response and absent acoustic reflexes.

Influence of the socieconomic level on the temporal resolution hearing skills in adults

ABSTRACT Objective: to investigate the influence of the socioeconomic level on the temporal resolution auditory ability of adults. Methods: the sample consisted of 48 subjects aged 18 to 50 years, divided into three groups: G1, 11 subjects at level A; G2, 19 in B1 and B2 and G3, 18 in C1, C2, D and E. All subjects presented responses in 20 dB HL in frequencies of 500 to 4000 Hz, during audiometric screening, type A tympanometry, presence of contralateral and ipsilateral acoustic reflexes, no neurological, psychiatric and / or psychological changes diagnosed; without audiological and / or otological complaints and with performance above 95% in the dichotic digit test. The Random Gap Detection and Gap-in-noise tests were performed. The Shapiro-Wilk test for normality analysis and the Kruskall Wallis test for socioeconomic stratum analysis, were used, both with 5% significance. Results: there were statistically significant differences between the groups in the Random Gap Detection in the frequency of 500 Hz and in the average of the frequencies, as a function of the socioeconomic level, the same not being observed in the Gap-in-noise. Conclusions: it is suggested that the socioeconomic level be taken into account in the analysis of the Random Gap Detection test.

Hearing, language, motor and social skills in the child development: a screening proposal

ABSTRACT Purpose: to analyze the hearing, language, motor and social skills of children and propose a screening of child development. Methods: 129 preschool children of both sexes, aged between three and six years old, enrolled in educational institutions and 25 teachers of kindergarten from public and private institutions, with no history of hearing disorders, with type A tympanometric curves and the presence of acoustic reflexes participated. For the children, the neuropsychomotor test, Denver II, and the evaluation of sound localization and temporal ordination of three verbal and non-verbal sounds were applied. For the educators responsible for the children, the Scale of Auditory Behaviors (SAB), was used. Results: most participants with normal SAB presented hearing abilities or standard Denver II; while in the amended SAB group, most participants presented alterations in Denver II or in the auditory abilities tests. It was found, also, that part of the children with standard Denver II were pointed, by the educators, as misbehaving in SAB. Conclusion: the combination of the findings of the Denver II, hearing tests of sound localization and temporal ordination and the SAB Scale is useful in the characterization of child development and, thus, the use of these three instruments for screening in this age group is recommended.