What is the Mastoid Bone?
The mastoid bone is a bone located behind the ear (felt as a hard bump behind the ear). Inside it looks like a honeycomb, with the spaces filled with air. These air cells are connected to the middle ear through an air filled cavity called the mastoid antrum. Although the mastoid bone serves as a reserve air supply to allow normal movement of the eardrum, its connection to the middle ear may also result in the spread of middle ear infections to the mastoid bone (mastoiditis).
What is a Mastoidectomy?
A mastoidectomy is a surgical procedure designed to remove infection or growths in the bone behind the ear (mastoid bone). Its purpose is to create a “safe” ear and prevent further damage to the hearing apparatus.
What Are the Indications for a Mastoidectomy?
A mastoidectomy is indicated for mastoiditis that does not respond to antibiotics. A mastoidectomy is also helpful in preventing further complications of mastoiditis. These include meningitis (infection in the fluid surrounding the brain), brain abscess (pocket of infection in the brain), or blood clots in the veins of the brain.
Mastoidectomy is often indicated for other diseases that spread to the mastoid bone, such as cholesteatoma. This procedure allows complete removal of these benign yet destructive growths. Occasionally, a mastoidectomy may be used to help find and repair an injured facial nerve.
What is Done in Preparation for a Mastoidectomy?
A complete physical examination of the ear area including the appearance of the outer ear, eardrum, and middle ear is performed. Facial Nerve function is also evaluated. Hearing tests and pictures (mastoid x-ray or CT scan) are also obtained prior to surgery.
What is Involved with a Mastoidectomy?
A mastoidectomy is performed with the patient fully asleep (under general anesthesia). A surgical cut (incision) is made behind the ear. The mastoid bone is then exposed and opened with a surgical drill. The infection or growth is then removed. The incision is closed with stitches under the skin. A drainage tube may also be placed.
Depending on the amount of infection or cholesteatoma present, various degrees of mastoidectomies can be performed.
In a simple mastoidectomy, the surgeon opens the bone and removes any infection. A tube may be placed in the eardrum to drain any pus or secretions present in the middle ear. Antibiotics are then given intravenously (through a vein) or by mouth.
A radical mastoidectomy removes the most bone and is indicated 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.
A modified radical mastoidectomy means that some middle ear bones are left in place and the eardrum is rebuilt (tympanosplasty). Both a modified radical and a radical mastoidectomy usually result in less than normal hearing. A hospital stay is usually required overnight for children.
What are the Risks and Complications of a Mastoidectomy?
Bleeding and/or infection of the wound area are possible complications with any incision. Antibiotics and good surgical technique help prevent this. Some blood-tinged drainage is common in the first two days. Other complications can include injury to the balance system, hearing loss, or facial nerve injury. Dizziness or a ringing in the ear (tinnitus) could also result.
Your doctor will discuss the possibility of these complications with you prior to your surgery.