Evaluation of hearing loss in tympanic membrane perforation.

To evaluate and analyse the hearing loss in tympanic membrane perforation based on size, site and duration of perforation. The material for this study was comprised of 100 patients of either sex and of age 15 years and above selected randomly. Size of tympanic membrane perforation was assessed under microscope using calibrated wire look. Patients were divided into three groups according to size; group I (0-9 mm(2)), Group II (9-30 mm(2)), Group III (≥ 30 mm(2)); according to site into anterior and posterior group; according to involvement of malleus into malleolar and non malleolar and according to duration into Group A (<1 year), Group B (1-5 years), Group C (≥ 5 years). Hearing loss was measured in each case with pure tone audiometry. Data was analysed statistically using paired t-test. Hearing loss increased as the perforation size increased [I vs. II (t - 4.23, p < 0.001), II vs. III (t - 8.19, p < 0.001), I vs. III (t - 11.68, p < 0.001)]. Hearing loss was more in posterior quadrant perforation than anterior quadrant perforation but difference was not significant statistically (t - 1.15, p > 0.05). Hearing loss was more in malleolar perforation (t - 5.74, p < 0.001). Hearing loss increased as the duration of disease increased [A vs. B (t - 2.01, p < 0.043), A vs. C (t - 5.49, p < 0.001), B vs. C (t - 4.14, p < 0.001)].