THE PARENTS' GUIDE TO OTITIS MEDIA (MIDDLE EAR FLUID)

Basic Anatomy and Workings of the Ear

The ear can be divided into three parts, consisting of the outer ear, the middle ear and the inner ear. The outer ear includes the pinna (the visible portion of the ear), the ear canal and the surface of the eardrum. The middle ear is the section behind the eardrum that is usually filled with air and contains the ossicles and the eustachian tube (this connects the middle ear to the back of the nose). The inner ear includes the cochlea which converts the sound into nerve impulses.

In a healthy ear, sound waves collect in the pinna, travel through the ear canal and cause the eardrum to move back and forth. Sound waves are transmitted by the movement of three bones into the inner ear, which in turn, transmit the sound energy to the brain, where we hear.

Click here for our interactive "Flash / Shockwave Presentation" of How The Ear Works.

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What is Otitis Media with Effusion?

One of the most common causes of conductive hearing loss in children is fluid in the middle ear cavity. Middle ear fluid is also referred to as Otitis Media with effusion. It may or may not be infectious in nature and is often a watery, mucous-like fluid which collects behind the eardrum. When the middle ear is filled with fluid, the movement of the eardrum and the ossicular chain is hindered. This could cause difficulty in hearing. The amount of hearing loss depends on the amount of fluid trapped in the middle ear. If the middle ear space becomes inflamed it is called Otitis Media. Otitis media most commonly occurs in children under three. Otitis Media usually occurs after an extended blockage of the eustachian tube. It can also be caused from: ear, nose, and throat infections; the common cold or flu; or enlarged adenoids.

Typically, children with this condition experience little or no pain and do not have a fever. This contrasts to an ear infection where a child may have a fever, sharp ear pain, and a bulging red eardrum. Also, unlike an ear infection, middle ear fluid is most often found in both ears at once.

Testing for Middle Ear Fluid

To detect middle ear fluid a child’s health care provider may use one of two tests. First the physician may look at a child’s eardrum with a pneumatic otoscope to visually check for fluid. If none can be seen, the health care provider will then blow a puff of air into the eardrum to see how well the eardrum moves. This test does not hurt and does not test for hearing ability. A second method of testing for middle ear fluid is a tympanometry. For this, a soft plug or probe tip, the size of a person’s baby fingertip is gently inserted into the ear canal. This probe is attached to a machine called a tympanometer. Air pressure is introduced into the ear canal, and the movement of the eardrum is measured. The results are divided into four categories. Type A, is considered normal eardrum activity. Type B, indicates possible fluid behind the eardrum. Type C indicates negative pressure in the middle ear. Type D indicates a perforation or presence of a PE (pressure equalization) tube in the eardrum. When middle ear fluid is present the usual result is a Type B tympanogram. Again, this test does not hurt and does not test for hearing loss.

Suppurative Otitis Media

Suppurative Otitis Media occurs when pus starts to build up in the middle ear space. This can be classified as either Acute or Chronic Otitis Media. Symptoms of Acute Otitis Media include severe ear pain, restlessness, redness of the eardrum and fever. It is often referred to as an ear infection. Acute Otitis Media usually responds well to medical treatment. Occasionally, the eardrum may burst and the fluid drains from the ear. If left untreated, Acute Otitis Media may lead to more sever middle or inner ear conditions. In a tympanometry test the results may reveal a type B or type C tympanogram.

Treatment of Otitis Media

The treatment of Otitis Media is controversial. There is friction regarding medical and surgical treatment. Studies support both methods as superior. In the end the decision is up to the parents and the child’s health care provider. Therefore it is important to weigh the pros and cons of all procedures.

First, some studies indicate that observation is best. Often after 3 to 6 months, middle ear fluid clears up in some children without treatment. The second option is treatment with antibiotics. This option may increase the chance and speed of the middle ear fluid going away. It may also decrease the possibility of middle ear infection. However, there are often side effects to drugs, such as diarrhea, and rashes. The development of drug-resistant strains of bacteria, and cost are other factors to consider. 

The third option is surgical intervention. In this minor procedure, the child is anaesthetized. A small incision is then made in the child’s eardrum and the fluid is carefully drained. Then a small plastic or metal tube, called a pressure equalization (PE) tube is put into the incision in the eardrum. These tubes are left in place until the health care specialist says they are no longer needed or they fall out. After the fluid is gone from the ear, the child’s hearing returns to normal. One third of children who have this operation performed need to repeat it within five years. However, although it seems invasive, this method has been effective. Please consult your health care provider for more information. Fortunately today with proper treatment, middle ear infections rarely lead to more serious conditions. Nonetheless, if not treated, Otitis Media can result in severe complications.

Prevention

Studies show that children who reside with smokers or spend time in daycare are at greater risk of developing ear infections. Eliminating children’s exposure to cigarette smoke and playmates who are sick, can minimize the risk of infections. Ear infections also occur more frequently during the winter months.