CPT® Code 69505

A mastoidectomy is a surgical procedure aimed at removing infected mastoid air cells, which are located within the mastoid process, a bony structure situated behind the ear that extends from the temporal bone of the skull. The procedure is typically indicated when there is an infection that has affected the mastoid air cells, leading to complications such as cholesteatoma or chronic ear infections. During the surgery, an incision is made behind the ear to expose the mastoid bone. In the case of a complete mastoidectomy, as described in CPT® code 69502, the entire air cell system is excised along with any purulent matter, debris, and infected tissue. This is often performed in response to acute infections. In contrast, CPT® code 69505 refers to a modified radical mastoidectomy, which is specifically performed for the management of cholesteatoma. This procedure involves the removal of the mastoid air cells while preserving the tympanic membrane and the structures of the middle ear. Additionally, the posterior and superior walls of the external auditory canal are excised to provide better access to the mastoid and attic of the middle ear. This distinction is crucial as it highlights the varying degrees of surgical intervention based on the underlying condition being treated, with the modified radical approach being less extensive than a radical mastoidectomy, which is indicated for more severe cases involving extensive cholesteatoma, as noted in CPT® code 69511.