Incidence and Preoperative Predictive Indicators of Incudal Necrosis in CSOM: A Prospective Study in a Tertiary Care Centre

Abstract

Both type of CSOM, tubotympanic which is considered safe as well as atticoantral which is considered unsafe may lead to erosion of the ossicular chain. Discontinuity of the ossicular chain is typically confirmed only during an operation. Knowing before surgery whether the patient has an ossicular discontinuity is important because it allows the surgeon to know the possibility of performing an ossiculoplasty and obtaining patient consent. The aims is to (1) study the incidence of incus necrosis in safe and unsafe CSOM. (2) Determine the preoperative predictive factors for incus necrosis. (3) Use angled otoscopes to determine the incidence of residual disease peroperative after conventional microscopic surgery. This is a prospective study carried out in the department of otorhinolaryngology, Govt Doon medical college, Dehradun from July 2014 to July 2016. A total of 100 patients who presented with CSOM and have not undergone any surgical procedure for the same were included in this study. Patients group was divided into cholesteatoma and non cholesteatoma group. Both groups were subdivided into intact and eroded incus group and were analysed in 11 parameters which were compared statistically. Incudal necrosis is more common in cholesteatoma group. In non cholesteatoma ears subtotal perforation with exposure of IS joint is reliable indicators of incudal necrosis. In non cholesteatoma group extension of cholesteatoma to tympanic sinus and mastoid and presence of persistent discharge are reliable indicators of necrosed incus. Moderate to moderately severe hearing loss indicate incudal necrosis in both groups therefore we conclude that these parameters can be reliably considered as predictors for incudal necrosis preoperatively.