Chronic otitis media (COM) is an important and a highly prevalent disease of the middle ear
and poses serious health problem worldwide especially in developing countries. Chronic otitis media is often accompanied by varying degree of conductive hearing loss². Loss of hearing is a national health problem with significant physical and psychosocial impact. The objective of this study is to correlate the size of perforation with hearing loss using pure tone audiogram and to evaluate the outcome of type 1 tympanoplasty in patients with chronic otitis media with tympanic membrane perforation at different sites.
Methods: The study was done on 120 patients with chronic otitis media who visited ENT and HNS OPD during Jan 2017 to Jan 2018. The patients were classified into four groups with each group   containing 30 patients, according to the type of tympanic membrane perforations. Group A consisted of   patients with small/medium perforation, group B with marginal perforation, group C with subtotal perforation and group D with total perforation. Type 1 tympanoplasty was done in all patients under general anaesthesia, after taking proper consent from all patients.   
Results: The mean pure tone average for small/medium perforations was 21.73dB, for marginal 27.11 dB, for subtotal 34.45dB and for  total perforation 43.38 Db. Mean air bone gap for small/medium, subtotal and total perforation was 13.45dB, 19.07dB, 32.38dB and 42.22dB respectively. Difference in mean pure tone average and mean ABG between different sizes of perforation is statistically significant. Hence we conclude that hearing loss increases with increase in size of perforation. Preoperatively, mean PTA threshold was 34.16dB and mean ABG was 24.26dB. Postoperatively, mean PTA threshold was 21.26dB and mean ABG was 11.26dB. The hearing improvement from preoperative level to 6 months postoperative level was statistically significant. Graft uptake in our study was seen in 88% of the cases. Out of 120 patients ,21 patients (17.5%) had residual perforation with highest percentage in group D(36.6%) followed by C(23.3%) and B(10%) as described in chart 1 above. Postoperative hearing outcome was excellent with hearing improvement with 10–15dB ABG, 10–20dB ABG, 15–25Db ABG and 20–33Db ABG in group A,B,C,D respectively,showing more improvement in hearing outcome with less ABG(air bone gape) in group A>B>C>D. similarly perforations were also divided in to anterior and posterior type depending on site of perforation In our study about 84 patients had posterior type perforation and rest 36 had anterior type of perforation. Posterior based perforations had good outcome in terms of hearing gain in dB, and ABG closure and less residual perforations than anterior based perforations.

Conclusion: In our study we found a statistically significant correlation between the size of perforation and the hearing loss and a statistically significant improvement in hearing following type I tympanoplasty.site of perforation also had statistically significant in terms of recurrence and hearing outcome.