Staging system for attic cholesteatoma
According to the EAONO/JOS 2015,4 the attic cholesteatoma was classified as follows:
Cholesteatoma in attic (stage I), epithelial shrink bag self-cleaning function (stage Ia), continuous accumulation of shrink bag keratin-debris (stage Ib), cholesteatoma involving two or more websites (stage II), intratemporal complications and/or pathological conditions of cholesteatoma (stage III), and intracranial cholesteatoma complications (stage IV).