Use of endoscope in teaching of otolaryngology residents about site and size of tympanic membrane perforation and its impact on degree of hearing loss in adult patients: A cross sectional study.

Objective To determine the association between site and size of perforation of the tympanic membrane and the level of conductive hearing. METHODS The cross-sectional study was conducted from November 2015 to October 2016 at Aga Khan University Hospital Karachi and comprised patients with tympanic membrane perforation without any other middle-ear disease. Karl-Storz Rigid Endoscope attached to a camera was used to take pictures of the tympanic membrane. Site of the perforation was determined using a vertical line to divide the membrane into two anterior and posterior halves. Size of the perforation was calculated as a percentage of the total membrane using Image J software. Data analysis was done using Stata 12. RESULTS Of the 55 patients, 29(53%) were males and 26(47%) were females. The overall mean age was 33+/-15 years. With every 5% increase in the size of perforation, the hearing loss increased by 1 decibel. A difference of 5.5 decibels was noted between anterior and posterior perforations of similar size. Conclusion Hearing loss increased with increase in the size of perforation.