INTRODUCTIONChronic suppurative otitis media (CSOM) is an inflammation of a part or whole of the mucoperiosteal lining of the middle ear cleft. It is a highly prevalent disease of the middle ear. Although the incidence and prevalence of CSOM has decreased in recent decades, due to improving hygiene and treatment, it is still a major health problem in both developing and developed countries.1,2 The tympanic membrane (TM) emulates an irregular cone and is about 9 mm in diameter. It is firmly attached to the malleus at the lateral process and at the umbo. The middle ear couples sound signals from the ear canal to the cochlea chain. The major transformer mechanism within the middle ear is the ratio of the TM area to the stapes footplate area (the areal ration). The TM gathers force over its entire surface and then couples the gathered force to the small footplate of the stapes. Human TM has an area that is 20 times larger than the footplate, thus, if the transformer action of the areal ratio is "ideal," the sound pressure applied to the inner ear by the stapes footplate should be 20 times or 26 dB larger than the sound pressure at the TM.
ABSTRACT
Background:The objective of the present study was to correlate the size and site of perforation with hearing loss in chronic suppurative otitis media (CSOM). Methods: The cross sectional study was conducted among a purposive sample of first 100 consecutive patients of unilateral inactive mucosal CSOM, who underwent myringoplasty at Department of otorhinolaryngology and Head and Neck Surgery Gujarat Adani Institute of Medical Science, Bhuj, Kutch, Gujarat. One hundred consecutive patients fulfilling the inclusion criteria were included in the study. In all the patients, a detailed history and a thorough ENT examination was followed by hearing assessment and measurement of the size of the perforation. Results: Infection was the most common etiology of tympanic membrane perforation in 92 (92%) cases and trauma in 08 (08%) with otorrhea as the most common presenting complaint. Half of the cases were in the age group of 20-30 years. Seventy-nine percentage cases had mild hearing loss whereas 19% had moderate hearing loss. Anterior quadrant perforations on an average had 31.4 dB hearing loss, whereas there was 43.9 dB average hearing loss in posterior quadrant perforations. Conclusions: It was observed that there is direct relationship between size and site of perforation and loss of hearing. There was less hearing loss in small sized perforations. Posterior quadrant perforations and malleolar perforations (MLs) had a greater hearing loss than anterior, multiple quadrant, or non-MLs.