The grafting of drum in case of perforation is necessary due to following reasons-
- As the tympanic membrane has a hole in it,the chances of getting water from outside into the middle ear through the perforation are always there while bathing or swimming.This will contaminate the middle ear and cause infection in it and the ear will start discharging pus.So a route of infection persists if the perforation is not closed. The patient has to leave the sport of swimming.Also if the patient has a discharging ear, it becomes a sourse of embarasement for him in public life.
- Due to perforation, the patient suffers some degree of hearing loss which depends on the site and size of perforation. If the perforation is small but is in the posteroinferior compartment opposite the round window area, itwill produce more hearing impairment.