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 (TYMPANOPLASTY).
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 child's surgery.