The benefit of high-frequency audiometry – a retrospective study

Abstract

Summary Introduction: High-frequency audiometry is not usually carried out during routine hearing examinations. It is a frequently used method at the ENT Clinic of the University Hospital Motol (especially in patients being treated for tumours of the pontocerebellar angle), although the exact indicative criteria for this have not been determined. We aimed to characterize a group of patients, using a method which improved the accuracy of the diagnostics. Material and methodology: We analysed 1,515 audiograms retrospectively. These audiograms were performed by using audiometer MADSEN Astera of GN Otometrics during 2011–2018 in 773 adults, aged 16–80 (47.79 ±13.54). They all underwent high-frequency audiometry comprising of all commonly examined frequencies up to 8 kHz, and also at higher frequencies of – 9 kHz, 10 kHz, 11.2 kHz, 12.5 kHz, 14 kHz a 16 kHz. The indication was very diverse – subjective hypacusis/hyperacusis, tinnitus, vestibulopathy, acutrauma, or an already known diagnosis of a pontocerebellar tumour. Results: We identifi ed a clinically signifi cant asymmetry or pathological elevation of the hearing threshold, which was only detectable at frequencies above 8 kHz in 52 patients (6.73%). This group consisted of patients with vestibular schwannoma (48.08%), other tumours and vascular malformations of the temporal region (11.53%), vestibulopathy (3.85%), and patients that had never developed a serious pathology (23.08%). They were mostly patients with straightforward hypacusis or tinnitus. Conclusion: In clinical practice, there are cases of patients with a hearing defect that can only be detected when HFA is performed. HFA clarifi es the diagnosis of hearing disorders and can lead to the detection of potentially life-threatening conditions such as tumours and vascular malformations of the otological area. Key words high-frequency audiometry – hearing loss – tinnitus