Audiological Evaluation and Cochlear Reserve in Posterior Canal Benign Paroxysmal Positional Vertigo

Abstract

Background: Benign paroxysmal positional vertigo (BPPV) is a peripheral vestibular disorder affecting the semicircular canal (SCC). It is important to determine the potential contribution of posterior canal BPPV (PC-BPPV) to function of cochlear outer hair cells, by application of Otoacoustic emission (DPOAE and TEOAE) and to investigate changes of pure tone audiometry (PTA) thresholds in patients suffering from PC-BPPV.Objective: This study aimed to assess the audiological and cochlear reserve in PC-BPPV. Patients and Methods: This prospective study involved twenty patients with PC-BPPV. All patients in this study were evaluated by the Dix Hallpike test. Basic audiological evaluations included pure tone audiometry (PTA), immittancemetry and otoacoustic emissions audiometry (OEA), which included transient-evoked otoacoustic emissions (TEOAE) and distortion product otoacoustic emissions (DPOAE). Results: There was a significant positive correlation between age and pure tone audiometry (PTA), which increased by increase of the age in the studied PC-BPPV patients. Also, there was a significant negative relationship only between DPOAE (1 KHz) and PTA (1 KHz) but DPOA at 2, 4, and 8 KHz revealed statistically non-significant difference at all other OAE PTA. Conclusion:We concluded that as the age increased, a statistically significant threshold increased at high frequencies (4000 to 8000 Hz) suggestive of presbycusis. Considering the correlation between PTA and DPOAE, we concluded that otoacoustic emissions could be a complementary modality for the detection and control of hearing abilities.