Abstract
We developed a new grading system to understand the complicated pathological changes of cholesteatoma in comparison to those of chronic otitis media. This grading system, based on the extent of the cholesteatoma and the surrounding pathlogical changes, is able to simply express the entire pathological condition of the ear with cholesteatoma. Using this grading system, we analyzed the ears of 48 children with cholesteatoma, who underwent tympanoplasty over the past ten years. Their ages ranged from 2 to 15 years with an average age of 8.5 years. The attic and mesotympanic cholesteatomas were associated with greater pathological changes than those observed in postero-superior quadrant cholesteatomas. The degree of the pathological change in the area surrounding the cholesteatoma appears to correlate with the degree of extention of the cholesteatoma. This system is thus considered to be useful for evaluating the improvement in the pathological conditions before and after surgery in patients with cholesteatoma.