A Study to Assess the Effect of Size & Site of Tympanic Membrane Perforation on Hearing Loss.

The objective of the study was to assess the effect of size & site of tympanic membrane perforation on hearing loss. The study was carried out in ENT department of a tertiary health care hospital, between October 2018 and March 2020 (a total of 18 months). Patients aged 15-50 years having chronic otitis media with dry central perforation were included in the study after taking informed written consent and were evaluated with detailed history, clinical examination including otomicroscopy, tuning fork tests and pure tone audiometry. The patients were then posted for Tympanoplasty and just prior to the procedure, the tympanic membrane perforation size was measured using the Castroviejo caliper and site was noted using otomicroscopy. The status of the middle ear mucosa and ossicles were also analyzed to ensure normal middle ear mucosa and normal ossicular mobility and continuity and only then were these patients included in the study. All the patients in the study were evaluated for hearing loss using air conduction measurements in pure tone audiometry done at 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 3000 Hz and 4000 Hz. Hearing loss was found to be directly proportional to the size of perforation in our study. The site of the perforation has a significant association with the degree of hearing loss. Those perforations with posterior quadrant involvement and multiple quadrant involvement had a higher hearing loss. From our study, we concluded that there is a significant relationship between size and site of the perforation and the amount of hearing loss.