Evidence of residual disease in ossicles of patients undergoing cholesteatoma removal.

For the past several years there has been much debate regarding the advisability of reusing the incus for ossicular reconstruction in cases involving cholesteatoma. There appears to be some evidence that microscopic foci of cholesteatoma in the incus could lead to reimplantation of the cholesteatoma should the incus be used in the reconstruction phase. In an effort to elucidate the incidence of microscopic residual cholesteatoma, the incudes of patients with cholesteatoma were examined both grossly in the operating room and microscopically in the laboratory for erosion and residual cholesteatoma. Our examination showed that a number of specimens apparently free of cholesteatoma after macroscopic examination had microscopic evidence of cholesteatoma. Likewise, microscopic examination of an incus that appeared to be free of residual cholesteatoma revealed epithelial cells deeply invading the bone. Macroscopic examination consistently underestimated the amount of erosion that was clearly evident upon histologic examination. In light of these findings, gross examination of the incus after removal of cholesteatoma is not reliably predictive of invasive microscopic disease. Reusing the ossicles in this situation creates the potential of reimplanting the disease.