ABSTRACT
Introduction: The tympanic cavity contains three ossicles in humans, the malleus, incus and stapes. These ossicles form a chain across the tympanic cavity from the tympanic membrane to fenestra vestibuli respectively. They develop from mesenchymal condensation of tubotympanic recess at the 6th week of intrauterine life. Later due to programmed cell death a part of tissue remains as ossicles. It attains adult size in the fetal life itself. However, studies have shown gain in size and weight even 2 years after birth. The ossicles help in sound conducting mechanism in hearing. These ossicles are vulnerable to damage in the various diseases of the middle ear cleft resulting into either partial or total loss. Incus is the most, followed by stapes and least by malleus. 20% mucosal diseases show ossicular damage, while squamous epithelial disease involve in 80% [1,2]. The integrity of the ossicular chain is most important for the transmission mechanism of external sounds to the inner ear fluids. Objectives: 1. To study the percentage of ossicular damage in the diseases of the middle ear cleft among the patients being operated for chronic suppurative otitis media in our tertiary care hospital. 2.To assess the extent and frequency of individual ossicular chain involvement in simple mucosal disease and squamous epithelial diseases. Methods: A prospective clinical study was conducted in our tertiary care hospital over a period of five and a half years in our tertiary care hospital among 100 cases of chronic suppurative otitis media after ethical committee clearance. Detailed clinical and radiological examinations of the patients were done and ossicular chain status was noted on table. Patients were also called up for regular follow up. Results: Ossicular chain erosion was mostly seen in squamosal disease, with incus and incudo-stapedial joint being the most common sites for ossicular erosion. Conclusion: it was concluded that long process of incus was the most commonly eroded structure, with the incus being the most commonly involved ossicle Few factors that were found to be associated with ossicular erosion were atticoantral disease, pediatric age group and bigger tympanic membrane perforations.