Myringotomy and ear tubes
Myringotomy is a surgical procedure in which a small incision is made in theeardrum (the tympanic membrane), usually in both ears. The word comes from myringa, modern Latin for drum membrane, and tome, Greek for cutting. Fluid in the middle ear can be sucked out through the incision.
Ear tubes, or tympanostomy tubes, are small tubes, open at both ends, that are inserted into the incisions in the eardrums during myringotomy. They come in various shapes and sizes and are made of plastic, metal, or both.
Myringotomy with the insertion of ear tubes is an optional treatment for inflammation of the middle ear with fluid collection (effusion), also called glueear, that lasts more than three months, and does not respond to drug treatment. It is the recommended treatment if the condition lasts four to six months. Effusion is the collection of fluid that escapes from blood vessels or thelymphatic system. In this case, the fluid collects in the middle ear.
Initially, acute inflammation of the middle ear with effusion is treated withone or two courses of antibiotics. Antihistamines and decongestants have been used, but they have not been proven effective unless there is also hay fever or some other allergic inflammation that contributes to the problem. Myringotomy with or without the insertion of ear tubes is NOT recommended for initial treatment of otherwise healthy children with middle ear inflammation witheffusion.
In about 10% of children, the effusion lasts for three months or longer, whenthe disease is considered chronic. In children with chronic disease, systemic steroids may help, but the evidence is not clear, and there are risks.
When medical treatment doesn't stop the effusion after three months in a child who is one to three years old, is otherwise healthy, and has hearing loss in both ears, myringotomy with insertion of ear tubes becomes an option. If the effusion lasts for four to six months, myringotomy with insertion of ear tubes is recommended.
The purpose of myringotomy is to relieve symptoms, to restore hearing, to take a sample of the fluid to examine in the laboratory in order to identify anymicroorganisms present, or to insert ear tubes.
Ear tubes can be inserted into the incision during myringotomy and left there. The eardrum heals around them, securing them in place. They usually fall out on their own in 6-12 months or are removed by a doctor.
While ear tubes are in place they keep the incision from closing, keeping a channel open between the middle ear and the outer ear. This allows fresh air to reach the middle ear, allowing fluid to drain out, and preventing pressurefrom building up in the middle ear. The patient's hearing returns to normal immediately after the insertion and the risk of recurrence diminishes.
Parents often report that children talk better, hear better, are less irritable, sleep better, and behave better after myringotomy with the insertion of ear tubes.
The procedure is usually done in an ambulatory surgical unit under general anesthesia, although some physicians do it in the office with sedation and local anesthesia, especially in older children. The ear is washed, a small incision made in the eardrum, the fluid sucked out, a tube inserted, and the ear packed with cotton to control bleeding.
A child undergoing myringotomy with the insertion of ear tubes may not have food or water for four to six hours before anesthesia. Antibiotics are usuallynot needed.
After the insertion there are a few steps to take to insure that everything heals correctly. The use of antimicrobial drops is controversial. Water shouldbe kept out of the ear canal until the eardrum is intact. A doctor should benotified if the tubes fall out. Many doctors also recommend that the child use ear plugs to keep water out of the ear during bathing or swimming, to reduce the risk of infection and discharge.
The risks of myringotomy with the insertion of ear tubes include: cutting theouter ear, formation at the myringotomy site of granular nodes due to inflammation, formation of a mass of skin cells and cholesterol in the middle ear that can grow and damage surrounding bone (cholesteatoma), and permanent perforation of the eardrum.
If the procedure is repeated, structural changes in the eardrum can occur, such as loss of tone (flaccidity), shrinkage or retraction, or hardening of a spot on the eardrum (tpymanosclerosis).
It is possible that the incision won't heal properly, leaving a permanent hole in the eardrum, which increases the risk of infection and can cause some hearing loss.
It is also possible that the ear tube will move inward and get trapped in themiddle ear, rather than move out into the external ear. The exact incidenceof tubes moving inward is not known, but it could increase the risk of further episodes of middle-ear inflammation, inflammation of the eardrum or the part of the skull directly behind the ear, formation of a mass in the middle ear, or infection due to the presence of a foreign body.
The surgery may not be a permanent cure. As many as 30% of children undergoing myringotomy with insertion of ear tubes need to undergo another procedure within five years.