Tympanic Membrane Perforation: It’s Correlation with Hearing Loss and Frequency Affected - An Analytical Study

Abstract

Objective: The correlation between tympanic membrane perforations and hearing loss was studied. Study Design: Cross sectional prospective study design. Setting: E. N. T OPD, at a tertiary referral center. Materials and Methods: 100 perforated ears in patients of CSOM safe were selected from May 2011 to September 2013. Instruments used for data collection/processing included questionnaires, oto-endoscopy and micro-otoscopy, Pure tone audiometer and image J software. Results: Sixty-three patients (27-males, 36-females), aged 10-56 years (mean age 23.2 years ± 11.8 years) with 100 perforated eardrums were studied. 37(58.7%) had bilateral TM perforations, 7(11.1%) right unilateral and 19(30.2%) left unilateral. The various sizes of perforation and their hearing loss were as follows: Group I (0-8 mm 2 ), n=18, with mean hearing loss 29.41 ± 4.39. Group II (8.1-30 mm 2 ), n=39, with mean hearing loss 34.69± 4.96. Group III (>30.1 mm 2 ), n = 43, with mean hearing loss= 38.79± 3.44. Difference was significant, P value 0.000. The various sites of perforations were Central (69 ears. Mean hearing loss 35.64 dB ± 5.31), Posterior (16 ears, mean hearing loss 39.99 dB ± 2.79) and Anterior (15 ears, mean hearing loss 30.1 dB ± 2.98). Difference was significant, P value 0.000. Lower frequencies were affected more than higher frequencies. Inverted 'V' pattern of audiograms was observed at 2000 Hz. Conclusion: A linear relationship existed between size and degree of hearing loss. Posterior perforations had a higher hearing loss. Lower frequencies were affected more in general. Inverted 'V' pattern of audiograms was observed with turning point at 2000 Hz.