The tympanic region of the skull in extant pinnipeds: A pilot study of auditory morphological disparity using linear morphometric principal component analysis.

Pinnipeds are unique semiaquatic taxa possessing adaptations to hear efficiently both in water and on land. Research over the past century is extremely limited on the auditory apparatus morphology of pinnipeds, which include the Families Phocidae (true seals), Otariidae (sea lions/fur seals), and Odobenidae (walruses). Our extensive literature review revealed inaccurate terminology of this region, with details corresponding only to terrestrial taxa, and a severe lack of information due to very few current studies. This demonstrates the need for evaluation and comparison of the auditory morphologies of modern terrestrial and semiaquatic carnivorans in relation to hearing. This initial study compares tympanic bullar morphologies of Phocidae to other pinnipeds and representatives of terrestrial carnivoran families. Morphological correlations of the basicranial auditory region were also compared within phocid subfamilies. Eleven skull measurements and about eleven calculated ratios were included in multiple principal component analyses to determine what areas of the auditory apparatus had the most significant morphological variation. This is the first study using this methodology, especially in reference to the hearing adaptations of pinnipeds, specifically in phocids. Results demonstrate distinct trends in phocid bullar morphology relative to other pinnipeds. Analyses reveal that: (1) phocids generally have different bullar morphology than otariids and odobenids; (2) Neomonachus schauinslandi (Hawaiian monk seal) and Neomonachus tropicalis (Caribbean monk seal) have unique morphology compared to phocids and other pinnipeds. Future work with increased number of specimens will further substantiate these findings and both ontogenetic and sexual variations will be examined.

[Endoscopic ear surgery -- Discipline establishment and technological innovation].

The application of microscope is a milestone in the history of otosurgery, which makes otologists deal with middle ear lesions more clearly and finely, and helps otologists expand the scope of treatment to the lateral skull base area, which greatly promotes the development of otosurgery. In the past 20 years, with the continuous improvement of endoscopic equipment research and development and the gradual improvement of endoscopic technology, the application of endoscopic technology in China has shown an explosive development, and Chinese otolaryngologists have experienced from the initial attempts of endoscopic technology, to the widespread popularization of innovative and applicable technology, and then to the feasibility of exploring the future innovative concepts. Endoscopic technology is another revolutionary push for the development of otosurgery after the microscope.

In vivo biodistribution and ototoxicity assessment of cationic liposomal-ceftriaxone via noninvasive trans-tympanic delivery in chinchilla models: Implications for otitis media therapy.

OBJECTIVES: We report the in vivo biodistribution and ototoxicity of cationic liposomal-ceftriaxone (CFX) delivered via ear drop formulation in adult chinchilla. METHODS: CFX was encapsulated in liposomes with size of ∼100 nm and surface charge of +20 mV. 100 µl liposomes or free drug was applied twice daily in both external ear canals of adult chinchillas for either 3 or 10 days. Study groups included free ceftriaxone (CFX, Day 3: n = 4, Day 10: n = 8), liposomal ceftriaxone (CFX-Lipo, Day 3: n = 4, Day 10: n = 8), and a systemic control group (Day 3: n = 4, Day 10: n = 4). Ceftriaxone delivery to the middle ear and systemic circulation was quantified by HPLC assays. Liposome transport was visualized via confocal microscopy. Auditory brainstem response (ABR) tests and cochlear histology were used to assess ototoxicity. RESULTS: Liposomal ceftriaxone (CFX-Lipo) displayed a ∼658-fold increase in drug delivery efficiency in the middle ear relative to the free CFX (8.548 ± 0.4638% vs. 0.013 ± 0.0009%, %Injected dose, Mean ± SEM). CFX measured in blood serum (48.2 ± 7.78 ng/ml) following CFX-Lipo treatment in ear was 41-fold lower compared to systemic free-CFX treatment (1990.7 ± 617.34 ng/ml). ABR tests and histological analysis indicated no ototoxicity due to the treatment. CONCLUSION: Cationic liposomal encapsulation results in potent drug delivery across the tympanic membrane to the middle ear with minimal systemic exposure and no ototoxicity.

Radiologic evaluation and clinical assessment of facial sinus in adults and children - computed tomography study.

OBJECTIVE: The facial sinus is a recess of the lateral retrotympanum located between the chorda tympani (ChT) and facial nerve (FN). Chronic otitis media with cholesteatoma often spreads from the pars flaccida to the facial sinus (FS). In stapedotomy, if an unfavorable ChT type is encountered, there is a need for removal of bone between the ChT and FN. The aim of the study was to assess FSs in adults and children according to Alicandri-Ciufelli classification, to measure FS width and depth in computed tomography scans, evaluate the correlation between measurements and different types of facial sinuses, and provide a clinical context of these findings. METHODS: Cone Beam Computed Tomography (CBCT) of 130 adults and High Resolution Computed Tomography of 140 children were reviewed. The type of facial sinus was assessed according to Alicardi-Ciufelli's classification in different age groups. Width of entrance to facial sinus (FSW) and depth of FS (FSD) were evaluated among age groups. RESULTS: Type A of FS is dominant in both adult and children populations included in the study. The average depth of FS was 2.31±1.43 mm and 2.01±0.90 in children and adults respectively. The width of FS was 3.99±0.69 and 3.39±0.98 in children and adults respectively. The depth of FS (FSD) presented significant deviations (ANOVA, p<0.05) among all three types and age groups. In 116/540 (21.5%) cases the value of FSD was below 1 mm. CONCLUSION: The qualitative classification of facial sinuses into types A, B and C, introduced by Alicandri-Ciufelli and al. is justified by statistically significant differences of depth between individual types of tympanic sinuses. Type A sinuses may be extremely shallow (<1 mm - As) or normal (>1 mm - An). Preoperative assessment of CT scans of the temporal bones gives crucial information about type and size of facial sinus. It may increase the safety of surgeries in this area and play a role in choosing an optimal approach and surgical tools.

An Absorbance Peak Template for Clinical Assessment of Sound Conduction in Newborn Ears.

PURPOSE: Power absorbance measures recorded over a wide range of frequencies allow for clinical inferences about the outer/middle ears' acoustic mechanics. A frequency-dependent feature in the newborn wideband absorbance response, the prominent mid-frequency absorbance peak, has been linked to middle-ear resonance. However, current normative methods were not designed to assess subtle changes in such features. This work aims to develop and validate an absorbance peak template (APT) for assessment of absorbance peaks in newborns. Additional objectives are to compare test performance of absorbance peaks and APTs to existing normative methods, to demonstrate APT-based methods for categorization of abnormal absorbance peaks, and to describe absorbance peak test-retest variability. METHOD: Peak absorbance and peak frequency were analyzed in a training data set (490 measurements in 84 newborn ears who passed transient evoked otoacoustic emissions [TEOAEs] screenings), and an APT was developed by computing normal limits on these two absorbance peak variables. Split-set analysis evaluated the reproducibility of APT, and test-retest analysis was performed. Test performance analysis, conveyed by area under the receiver operating characteristic curve (AROC) and 95% confidence intervals (CIs), compared absorbance peak variables to absorbance area indices (AAIs) in a validation data set (359 ears that passed distortion-product OAE [DPOAE] screening and 64 ears that failed). APT-based assessment paradigms for normal and abnormal ears were compared to the common absorbance normative range paradigm. RESULTS: Split-set analysis demonstrated a good reproducibility of APT, and test-retest of absorbance peak variables showed that they were stable measures for clinical assessment. Test performance of peak absorbance (AROC = 0.83; 95% CI [0.77, 0.88]) was comparable to the top-performing AAI variables (AROC = 0.85; 95% CI [0.80, 0.90]). APT-based assessment categorized measurements based on their peak absorbance and peak frequency and enhanced the detection of subtle frequency changes that were missed by the normative range method. CONCLUSION: Analysis of absorbance peaks guided by APT has the potential to simplify and improve assessments of sound conduction pathways in newborn ears and can be used together with or in-place of current methods for analysis of wideband absorbance data.

Assessment of middle ear function after conventional or endoscopic microdebrider assisted adenoidectomy.

Objectives: To compare pre- and post-operative pure tone audiometric and impedance audiometric analysis following conventional and endoscopic microdebrider assisted adenoidectomy and compare the outcomes. Methods: Patients diagnosed with chronic adenoiditis were divided in groups of 25 each. Patients in the first group underwent conventional curettage adenoidectomy, while those in second group underwent endoscopic microdebrider assisted adenoidectomy. Pre- and post-operative pure tone and impedance audiometry were performed for all patients and outcomes were compared. Results: The endoscopic microdebrider assisted method resulted in significantly better outcomes compared to conventional curettage. Criteria such as hearing threshold (p value 0.004 at second follow-up), peak pressure (p value 0.045 at first follow-up) and tympanogram (p value 0.016) showed that the endoscopic method was better, while peak compliance (p value 0.340 at first follow-up) did not show any significant difference between groups. Conclusions: The endoscopic microdebrider assisted method for adenoidectomy has a definite advantage of better visualisation resulting in better clearance of tissue, leading to enhanced middle ear function compared to conventional curettage.

Assessment of middle ear structure and function with optical coherence tomography.

BACKGROUND: Current clinical tests for middle ear (ME) injuries and related conductive hearing loss (CHL) are lengthy and costly, lacking the ability to noninvasively evaluate both structure and function in real time. Optical coherence tomography (OCT) provides both, but its application to the audiological clinic is currently limited. OBJECTIVE: Adapt and use a commercial Spectral-Domain OCT (SD-OCT) to evaluate anatomy and sound-evoked vibrations of the tympanic membrane (TM) and ossicles in the human ME. MATERIALS AND METHODS: SD-OCT was used to capture high-resolution three-dimensional (3D) ME images and measure sound-induced vibrations of the TM and ossicles in fresh human temporal bones. RESULTS: The 3D images provided thickness maps of the TM. The system was, with some software adaptations, also capable of phase-sensitive vibrometry. Measurements revealed several modes of TM vibration that became more complex with frequency. Vibrations were also measured from the incus, through the TM. This quantified ME sound transmission, which is the essential measure to assess CHL. CONCLUSION AND SIGNIFICANCE: We adapted a commercial SD-OCT to visualize the anatomy and function of the human ME. OCT has the potential to revolutionize point-of-care assessment of ME disruptions that lead to CHL which are otherwise indistinguishable via otoscopy.

Assessment of the Eustachian tube: a review.

BACKGROUND: Dysfunction of the Eustachian tube (ET) can lead to negative pressure within the middle ear, which, in turn, causes various pathological changes. Multiple testing methods for ET function have been devised, each with its own advantages and disadvantages. Knowing the characteristics of each ET function test and the unique characteristics of ET dysfunction (ETD) in children are prerequisites for choosing the optimal assessment method. For a comprehensive diagnosis, assessment should also include the localisation of any sites of obstruction. This review aims to summarise the methods of evaluating ET function and locating sites of ET lesions. METHODS: Articles evaluating ET function, localising lesions in the ET, and ETD in children were collected from the PubMed database. We selected only relevant English publications. RESULTS: ETD in children has different characteristics to those in adults. The appropriate tests for assessing ET function depend on the specific conditions of the individual patient. Valsalva computed tomography can provide information on the soft and bony anatomy of the ET to facilitate identification of lesion sites. CONCLUSION: An accurate diagnosis should be based on a combined analysis of objective and subjective results, with interpretation made in conjunction with clinical history and physical examination. A comprehensive assessment should include lesion localisation. When assessing ETD in children, it is important to take into account the characteristics of this population.

Assessment of subjective image quality, contrast to noise ratio and modulation transfer function in the middle ear using a novel full body cone beam computed tomography device.

BACKGROUND: Multi slice computed tomography (MSCT) is the most common used method in middle ear imaging. However, MSCT lacks the ability to distinguish the ossicular chain microstructures in detail resulting in poorer diagnostic outcomes. Novel cone beam computed tomography (CBCT) devices' image resolution is, on the other hand, better than MSCT resolution. The aim of this study was to optimize imaging parameters of a novel full body CBCT device to obtain optimal contrast to noise ratio (CNR) with low effective dose, and to optimize its clinical usability. METHODS: Imaging of five anonymous excised human cadaver temporal bones, the acquisition of the effective doses and the CNR measurements were performed for images acquired on using Planmed XFI® full body CBCT device (Planmed Oy, Helsinki, Finland) with a voxel size of 75 µm. All images acquired from the specimens using 10 different imaging protocols varying from their tube current exposure time product (mAs) and tube voltage (kVp) were analyzed for eight anatomical landmarks and evaluated by three evaluators. RESULTS: With the exception of protocol with 90 kVp 100 mAs, all other protocols used are competent to image the finest structures. With a moderate effective dose (86.5 µSv), protocol with 90 kV 450 mAs was chosen the best protocol used in this study. A significant correlation between CNR and clinical image quality of the protocols was observed in linear regression model. Using the optimized imaging parameters, we were able to distinguish even the most delicate middle ear structures in 2D images and produce accurate 3D reconstructions. CONCLUSIONS: In this ex vivo experiment, the new Planmed XFI® full body CBCT device produced excellent 2D resolution and easily created 3D reconstructions in middle ear imaging with moderate effective doses. This device would be suitable for middle ear diagnostics and for e.g., preoperative planning. Furthermore, the results of this study can be used to optimize the effective dose by selecting appropriate exposure parameters depending on the diagnostic task.

Assessment of jugular bulb variability based on 3D surface models: quantitative measurements and surgical implications.

PURPOSE: High-riding jugular bulbs (JBs) among other anatomical variations can limit surgical access during lateral skull base surgery or middle ear surgery and must be carefully assessed preoperatively. We reconstruct 3D surface models to evaluate recent JB classification systems and assess the variability in the JB and surrounding structures. METHODS: 3D surface models were reconstructed from 46 temporal bones from computed tomography scans. Two independent raters visually assessed the height of the JB in the 3D models. Distances between the round window and the JB dome were measured to evaluate the spacing of this area. Additional distances between landmarks on surrounding structures were measured and statistically analyzed to describe the anatomical variability between and within subjects. RESULTS: The visual classification revealed that 30% of the specimens had no JB, 63% a low JB, and 7% a high-riding JB. The measured mean distance from the round window to the jugular bulb ranges between 3.22 ± 0.97 mm and 10.34 ± 1.41 mm. The distance measurement (error rate 5%) was more accurate than the visual classification (error rate 15%). The variability of the JB was higher than for the surrounding structures. No systematic laterality was found for any structure. CONCLUSION: Qualitative analysis in 3D models can contribute to a better spatial orientation in the lateral skull base and, thereby, have important implications during planning of middle ear and lateral skull base surgery.

Healthcare consumption among subjects with otitis media undergoing middle ear surgery-analysis of cost drivers.

PURPOSE: To map healthcare utilized by subjects with chronic otitis media, with or without cholesteatoma and perform a cost analysis to determine key drivers of healthcare expenditure. METHODS: A registry study of 656 adult subjects with chronic otitis media that underwent a middle ear surgery between 2014 and 2018. Healthcare contacts related to all publicly funded specialist ENT care, audiological care and primary care for a disease of the ear and mastoid process were extracted. The data are extracted from the Swedish National Patient Registry on subjects that reside in western Sweden. RESULTS: Subjects made 13,782 healthcare contacts at a total cost 61.1 million SEK (6.0 million EUR) between 2014 and 2018. The mean cost per subject was 93,075 SEK (9071 EUR) and ranged between 3971 SEK (387 EUR) and 468,711 SEK (45,683 EUR) per individual. In the most expensive quartile of subjects, mean cost was 192,353 SEK (18,747 EUR) over the 5-year period. These subjects made 3227 ENT contacts (roughly four each year) and 60% of total costs were associated with in-patient ENT care. CONCLUSION: Patients with chronic otitis media are associated with high ENT resource utilization that does not diminish after surgical intervention and the disease places a long-term burden on healthcare systems. Significant costs are attributed to revision surgeries, indicating that these patients could be managed more effectively. In many such cases, reoperation cannot be avoided, especially due to recurrence of cholesteatoma. However, in some patients, when the indication for subsequent surgery is only hearing improvement, alternative options, such as hearing aids or implants, should also be considered. This is especially true in difficult cases, where revision ossiculoplasty is likely.

Wideband absorbance for the assessment of pressure equalizing tubes patency in children.

OBJECTIVES: To analyze the feasibility of using wideband absorbance to verify the patency of pressure equalizing tubes (PETs) in clinical practice and to present the response pattern of this measure for ears with patent PET. METHODS: This observational case-control type study evaluated 48 ears of 30 children with severe or profound hearing loss, aged 10-44 months, of both sexes. The subjects were subdivided into two groups: 24 ears with Sheppard type PET (experimental group - EG) and 24 ears with normal middle ear (control group - CG), paired with the EG, according to age, sex, and ear evaluated. To obtain the wideband absorbance, a Middle-Ear Power Analyzer, version 5.0 (Mimosa Acoustics), was used, and absorbance values for pure tone and chirp stimuli were analyzed. RESULTS: There was no influence of ear (right or left) on the measurements obtained. The EG showed higher absorbance values at low frequencies. Although the two stimuli made it possible to identify the difference in acoustic transfer function between the groups studied, compared to pure tone, the chirp stimulus allowed identification of differences in a higher number of frequencies. CONCLUSIONS: Ears with a patent PET present an acoustic transfer pattern that differs from that obtained for normal middle ears, with a higher absorbance at low frequencies. Both pure tone and chirp stimuli can be used to identify such differences, nevertheless, the use of chirp stimulus is recommended, since it allows differentiation over a wider frequency range.

High-Speed Human Temporal Bone Sectioning for the Assessment of COVID-19-Associated Middle Ear Pathology.

Histopathologic analysis of human temporal bone sections is a fundamental technique for studying inner and middle ear pathology. Temporal bone sections are prepared by postmortem temporal bone harvest, fixation, decalcification, embedding, and staining. Due to the density of the temporal bone, decalcification is a time-consuming and resource-intensive process; complete tissue preparation may take 9-10 months on average. This slows otopathology research and hinders time-sensitive studies, such as those relevant to the COVID-19 pandemic. This paper describes a technique for the rapid preparation and decalcification of temporal bone sections to speed tissue processing. Temporal bones were harvested postmortem using standard techniques and fixed in 10% formalin. A precision microsaw with twin diamond blades was used to cut each section into three thick sections. Thick temporal bone sections were then decalcified in decalcifying solution for 7-10 days before being embedded in paraffin, sectioned into thin (10 µm) sections using a cryotome, and mounted on uncharged slides. Tissue samples were then deparaffinized and rehydrated for antibody staining (ACE2, TMPRSS2, Furin) and imaged. This technique reduced the time from harvest to tissue analysis from 9-10 months to 10-14 days. High-speed temporal bone sectioning may increase the speed of otopathology research and reduce the resources necessary for tissue preparation, while also facilitating time-sensitive studies such as those related to COVID-19.

Persisting variance in middle ear ventilation tube insertion in Auckland children: why ethnic disparity continues.

AIM: Insertion of ventilation tubes (VTs) is a common surgical treatment for recurrent and persistent otitis media, but surgical practice varies internationally. The current study explored variations in practice within New Zealand by examining VT insertion rates. The aim of the study was to determine time trends and current variations in VT insertion rates by ethnicity and district health board (DHB), with a focus on comparison of two DHBs in Auckland (Counties Manukau and Auckland DHB) to national average data. METHOD: Data for surgical procedures were analysed in the Atlas of Healthcare Variation domain, available via the Health Quality & Safety Commission website. Publicly funded events for New Zealand residents over a 10-year period (2009-2018) were examined for 0-4-year-olds. Individuals were assigned to their DHB of residence. VT rates for each DHB are presented per 1,000 population, with upper and lower confidence intervals calculated to the 95% level. RESULTS: There was a general decline in the rates of VT insertions for the 0-4-year-olds over the 2009-2018 decade. Analysis of the 2018 year showed variation by ethnicity and DHB. In CMDHB, ADHB and nationally, Asian and Pacific ethnic groups had the lowest rates of VT insertions compared to other ethnic groups. In CMDHB, the VT rates for Maori, Pacific and Asian children were less than half that of their respective groups in ADHB. The NZ European/Other ethnic group had the highest rates of VT insertions in CMDHB and nationally, but in ADHB, the rate for the NZ European/Other group was similar to that for Maori. CONCLUSION: These results are incongruent with evidence that Maori and Pacific children in New Zealand experience a greater burden of middle ear disease than NZ European children. The finding of persisting inequities in VT treatment for middle ear disease in 0-4-year-olds, with greatest impact on Pacific children, suggests that there may be a need for targeted middle ear screening for preschool children to detect pre-schoolers with ear disease, earlier than the 4-year-old B4 School Check.

12-month effect of middle ear pressure therapy with the EFET01 device for intractable definite Meniere's disease and delayed endolymphatic hydrops after certification by the public health insurance system in Japan.

BACKGROUND: Middle ear pressure therapy (MEPT) is effective for intractable vertigo in patients with definite Meniere's disease (MD) and treatment-refractory delayed endolymphatic hydrops (DEH). Four-month MEPT with the EFET01®, an MEPT device developed in Japan and covered by national health insurance since September 2018, has shown efficacy. However, efficacy and safety after 12 months of treatment, which is appropriate for determining the therapeutic effect of MEPT devices, is unclear. OBJECTIVES: Examine the therapeutic effect of 12-month MEPT using the ETET01®. MATERIAL AND METHODS: Patients underwent MEPT using the EFET01® from September 2018 to July 2021. Thirty-three patients followed for >12 months were enrolled in this retrospective study. Clinical data were evaluated in the first and second 6-month treatment periods. Data from the second 6-month period were compared with data from an MEPT study using a different device. RESULTS: MEPT with the EFET01® significantly improved vertigo in the first period, with further improvement in the second period. The efficacy and safety were comparable to MEPT with other devices. CONCLUSIONS: MEPT with the EFET01® is effective for intractable vertigo in patients with definite MD and DEH, and 12-month follow-up is recommended. SIGNIFICANCE: The efficacy of 12-month MEPT with the EFET01® was demonstrated.

Efficiency of a novel middle ear pressure device for intractable definite Meniere's disease and delayed endolymphatic hydrops after certification by the public health insurance system in Japan.

BACKGROUND: Middle ear pressure therapy (MEPT) is effective in treating intractable vertigo in patients with definite Meniere's disease (MD) and delayed endolymphatic hydrops (DEH) refractory to conservative treatment. A novel middle ear pressure device, the EFET01®, which requires no transtympanic ventilation tubes, was developed in Japan, approved by the Japanese Ministry of Health, Labour and Welfare, and has been used under Japanese national health insurance since September 2018. OBJECTIVES: To examine short-term therapeutic effect of MEPT using the ETET01® compared with previous clinical trial results. METHODS: Patients selected according to Japan Society for Equilibrium Research (JSER) guidelines underwent MEPT using the EFET01 from September 2018 to July 2021, and 44 patients were enrolled in this retrospective study. Clinical data analysed at 4 months after the start of MEPT were compared with those of the previous clinical trial for the EFET01. RESULTS: MEPT using the EFET01 showed the same therapeutic efficacy as that of the previous clinical trial, i.e. improvement in the intensity and frequency of vertigo with no effect on hearing, even under JSER guidelines for proper use of MEPT. CONCLUSION: MEPT using the EFET01 provided an effective treatment option for intractable vertigo in patients with definite MD and DEH.

Improved assessment of middle ear recurrent/residual cholesteatomas using temporal subtraction CT.

PURPOSE: The purpose of this study was to investigate the usefulness of temporal subtraction CT (TSCT) of temporal bone CT for the detection of postoperative recurrent/residual cholesteatoma of the middle ear. METHODS: Thirty-two consecutive patients with surgically proven postoperative recurrent/residual cholesteatoma and 14 consecutive patients without recurrent/residual lesion matched the selection criteria and were retrospectively evaluated. TSCT imaging was generated with the use of serial postoperative CT. Two experienced radiologists and two residents evaluated the presence of bone erosive change by comparison serial CT studies, and CT and TSCT. The detection rate of bone erosive change, sensitivity and specificity of the recurrence/residual lesions, and reading time for each reader were evaluated. RESULTS: TSCT + CT significantly improved the detection of bone erosive changes compared to CT-only evaluation (17.4-41.3% vs. 37.0-58.7%, p = 0.008-0.046). The mean sensitivity and specificity of TSCT + CT for experienced radiologists were 0.77 and 1.00, and 0.52 and 0.97 without TSCT. The mean sensitivity and specificity of TSCT + CT for residents were 0.64 and 1.00, and 0.41 and 1.00 without TSCT. Sensitivity showed an increase in all readers. The use of TSCT significantly reduced the reading time per case in all readers (p < 0.001). CONCLUSION: TSCT improves the depiction of newly occurring progressive bone erosive changes, and detection sensitivity and reading time in postoperative recurrence/residual cholesteatoma of middle ear.

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.