Mastoidectomy Health Article

Definition

A mastoidectomy is a surgical procedure that removes an infected portion of the mastoid bone when medical treatment is not effective.

Purpose

A mastoidectomy is performed to remove infected mastoid air cells resulting from ear infections, such as mastoiditis or chronic otitis, or by inflammatory disease of the middle ear (cholesteatoma). The mastoid air cells are open spaces containing air that are located throughout the mastoid bone, the prominent bone located behind the ear that projects from the temporal bone of the skull. The air cells are connected to a cavity in the upper part of the bone, which is in turn connected to the middle ear. Aggressive infections in the middle ear can thus sometimes spread through the mastoid bone. When antibiotics can't clear this infection, it may be necessary to remove the infected area by surgery. The primary goal of the surgery is to completely remove infection so as to produce an infection-free ear. Mastoidectomies are also performed sometimes to repair paralyzed facial nerves.

Demographics

According to the American Society for Microbiology, middle ear infections increased in the United States from approximately three million cases in 1975 to over nine million in 1997. Middle ear infections are now the second leading cause of office visits to physicians, and this diagnosis accounts for over 40% of all outpatient antibiotic use. Ear infections are also very common in children between the ages of six months and two years. Most children have at least one ear infection before their eighth birthday.

Description

A mastoidectomy is performed with the patient fully asleep under general anesthesia. There are several different types of mastoidectomy procedures, depending on the amount of infection present:

• Simple (or closed) mastoidectomy. The operation is performed through the ear or through a cut (incision) behind the ear. The surgeon opens the mastoid bone and removes the infected air cells. The eardrum is incised to drain the middle ear. Topical antibiotics are then placed in the ear.
• Radical mastoidectomy. The procedure removes the most bone and is usually performed for extensive spread of a cholesteatoma. The eardrum and middle ear structures may be completely removed. Usually the stapes, the "stirrup" shaped bone, is spared if possible to help preserve some hearing.
• Modified radical mastoidectomy. In this procedure, some middle ear bones are left in place and the eardrum is rebuilt by tympanoplasty.

After surgery, the wound is stitched up around a drainage tube and a dressing is applied.