A Study of Correlation of Size and Site of Perforation with Deafness

Abstract

Introduction: Otitis media is an inflammation of a part or all the mucoperiosteal lining of the middle ear cleft. It is a highly prevalent disease of the middle ear. Chronic suppurative otitis media is a serious health problem worldwide and it is more critical in developing countries where large percentage of the population lack specialized medical care, suffer from malnutrition and live in poor hygienic environmental conditions. because of the high incidence of conductive hearing loss caused by central perforations of tympanic membrane, the conflicting reports regarding the effect of perforations on hearing loss, this project has been under taken to study the clinical profile of CSOM & effects of tympanic membrane perforations on the degree of hearing loss. Material & methods: The present study was carried out in 500 patients (640 ears) presenting with unilateral or bilateral perforations of tympanic membrane, in the Department of E.N.T., Sir T. Hospital, Bhavnagar. It was carried out during the rime period of November 2008 to February 2010. Results: The perforations occupying all the four quadrants were maximum in 205 cases (i.e. 32.0%). In perforations involving two quadrant, it was observed that in perforations located over antero-superior + antero-inferior quadrants, those occupying 25-50% of effective vibratory surface area of tympanic membrane had significantly greater hearing loss than those involving <25% of effective tympanic membrane surface area. In perforations involving three quadrants, were seen to be distributed over antero-superior + antero-inferior + poster-inferior quadrants. The significant difference in mean average hearing losses of perforations involving <25% and 25-50% of effective vibratory surface area of tympanic membrane, showing that some increase in size of perforation, so long the perforation is confined to three quadrants produce significant effect on hearing loss.
Conclusion: It was observed that in perforations located over antero-superior + antero-inferior quadrants, those occupying 25-50% of effective vibratory surface area of tympanic membrane had significantly greater hearing loss than those involving <25% of effective tympanic membrane surface area.