Effect of Small Tympanic Membrane Perforations on Hearing

Abstract

Objective: The effects of perforations on middle-ear sound transmission are not well defined because of middle ears with TM perforations generally have additional pathological changes. The aim of the study is to compare the hearing loses in tympanic membrane perforation of quadrants with exclusion of the possible middle and inner ear pathologies that may have resulted any hearing loss. Material and Methods: Patients who attended Otorhinolaringology-Head Neck Surgery Department, and underwent type 1 tympanoplasty between 2011 January and 2014 December were retrospectively analyzed. Size of perforation had been described in millimeter and location was grouped as anteroinferior (AI), anterosuperior (AS), posteroinferior (PI), posterosuperior (PS). Results: Sixty-five patients (65 ears) with isolated TM perforations were included in the study. Twenty-seven (41.5%) perforations were in PI, 8 (12.3%) perforations PS, 25 (38.4%) perforations AI, and 5 (7.7%) perforations AS-localized. There were not statistically significant differences between 4 groups at each frequency (0.5 kHz, 1 kHz, 2 kHz, and 4 kHz) for air-bone gap. Statistically significant decrease of bone conduction thresholds was observed in AI group when compared with other groups at higher frequencies (2 and 4 kHz, p<0.05) and between small and moderate perforation groups in all frequencies (500, 1000, 2000 ve 4000 Hz, p value: p=0.025, p=0.025, p=0.037, p=0.034 respectively). Conclusion: The results showed that the air-bone gap increases with increasing size of perforation. However, no statistically significant air-bone gap differences between tympanic membrane quadrants were determined.