Saturday, December 20, 2014

Definition

Otitis media is an inflammation of the middle ear (the cavity between the eardrum and the inner ear).

Description

The eustachian tubes equalize the pressure between the middle ear cavity and the outside atmosphere and allow fluid and mucus to drain out of the middle ear cavity. Inflammation of the middle ear causes the tubes to close causing the fluid to become trapped. Bacteria from the back of the nose travel through the eustachian tube directly into the middle ear cavity and multiply in the fluid.

The inflammation can occur as a result of an infection extending up the eustachian tube. This tube may become blocked by a bacterial or viral infection or by enlarged adenoids. Fluid produced by the inflammation cannot drain off through the tube and instead collects in the middle ear.

Otitis media that fails to clear up after three months or more is called chronic otitis media.

If purulent otitis media returns time and again, this is called recurrent otitis media.

Causes

Children are more commonly affected than adults because of the small size and horizontal position of their eustachian tube (the passage that connects the back of the nose to the middle ear). Otitis media affects about 2/3 of youngsters at least once before they reach their second birthday.

The four main causes of otitis media are allergy, infection, blockage of the eustachian tube and nutritional deficiency.

Allergy. Studies have shown that food and airborne allergies can cause otitis media. The most common offending foods are milk products (from cows), wheat, egg white, peanut products, soy, corn, oranges, tomatoes and chicken. The most common airborne allergens are cigarette smoke, pollen, animal dander, house dust, mold, fungi, sulfur dioxide, bacteria and volatile organic compounds such as formaldehyde, pesticides and herbicides.

Infection. Otitis media infections are caused by viruses or bacteria that infect the cells lining the eustachian tube, throat and middle ear. When infected, these cells become swollen and secrete a thick mucus that may clog the eustachian tube and cause fluid and pressure to build behind the eardrum. Some of the most common bacteria to cause this infection are Streptococcus pneumoniae, Haemophilus influenzae and moraxella catarrhalis.

Blockage of the eustachian tube. This obstruction can be a result of swollen tonsils or adenoids or problems involving the bones of the cranium, the temporomandibular joint (located at the jaw) or the cervical spine.

Nutritional deficiency. Researchers have found that children with vitamin A, zinc and iron deficiencies are more susceptible to upper respiratory and ear infections. Additionally, large amounts of prostaglandins (fatty acids found naturally in all people) and leukotrienes may also play a part.

Additionally, in infants, otitis media has been associated with bottle feeding. Breast feeding provides two protective mechanisms. One is the suction created by sucking on the breast helps close the ear canal and prevents reflux of particles and bacteria into the middle ear. Second is the general protection from infections provided by the mother’s antibodies crossing over to the baby in the mother’s milk.

Symptoms

Serous otitis media may not cause any symptoms, however, fluid remaining in the middle ear for a long period of time may result in hearing loss. Although this condition can develop on its own, it most commonly occurs after being treated for acute otitis media.

Acute otitis media causes sudden, severe earache, deafness, and tinnitus (ringing or buzzing in the ear), sense of fullness in the ear, irritability, tugging or rubbing the ear, an unwillingness to lie down, fever, headache, a change in appetite or sleeping patterns, fluid leaking from the ear, nausea and difficulty in speaking and hearing. Occasionally, the eardrum can burst, which causes a discharge of pus and relief of pain.

Complications of a single episode of otitis media are rare and include otitis externa (inflammation of the outer ear), and spread inward from the ear to the skull, causing, mastoiditis (inflammation of the mastoid bone cells), or into the brain, causing meningitis (inflammation of the membranes covering the brain and spinal cord) or a brain abscess.

Complications recurrent in otitis media include damage to the bones in the middle ear (sometimes causing total deafness) or a cholesteatoma (a matted ball of skin debris which can erode bone and cause further damage to the ear).

Diagnosis

Otitis media can only be detected by examining the ear with an otoscope. Only by directly looking in the ear and seeing how the eardrum responds to gentle pressure can the diagnosis be confirmed. In addition, two tests may be performed to give the doctor information that cannot be learned through observation only.

One of these tests is an audiogram, in which tones are sounded at various pitches. An audiogram is used to measure how much hearing loss has occurred. The second test, called a tympanogram, measures the air pressure in the middle ear; this indicates how well the eustachian tube is functioning.

In recurrent cases or when an acute case does not respond to treatment, it may be necessary to obtain a culture from the middle ear, through the eardrum. This is usually done by an otolaryngologist.

Treatment

After the diagnosis is made, a treatment plan is considered, taking into account the patient’s age, risk factors for having resistant bacteria, immunization status, and hearing status. For low-risk children, the preferred treatment is to hold antibiotics for 24 hours and recheck the following day. Many children improve with only treatment for pain with analgesic eardrops, and then do not need any antibiotics. High-risk children are treated with antibiotics.

The use of prophylactic antibiotics to prevent recurrent otitis media is controversial.

Surgery

Your doctor may recommend surgery if the child's infection fails to respond to antibiotics, if the ear infections are chronic or hearing loss is indicated. The most common type of surgery is myringotomy.

Myringotomy. This kind of surgery offers relief to children and some adults who suffer recurrent ear infections or persistent fluid in the middle ear, which can lead to hearing loss. In a short and simple outpatient procedure, an otolaryngologist makes a small incision in the eardrum and inserts a tiny ventilation tube called a tympanostomy tube. The tube promotes drainage of fluid from the middle ear and keeps it from recurring. The procedure also usually results in a marked reduction in the number and severity of ear infections. The tube will fall out on its own within 3 to 18 months. Additional myringotomies may be necessary.

Other options include:

Adenoidectomy. As a last resort the doctor may suggest removing the adenoids (adenoidectomy). This procedure is only recommended for children 4 years of age or older, if the serous otitis media has lasted three months or more and the adenoids are repeatedly inflamed.

Tonsillectomy. As a last resort the doctor may suggest removing the tonsils (tonsillectomy). This procedure is only recommended for children 4 years of age or older, if the serous otitis media has lasted three months or more and the tonsils are repeatedly inflamed.

If there is damage to the eardrum the doctor may suggest tympanoplasty (a plastic operative procedure to repair a damaged eardrum) or myringoplasty (surgical closure of a perforation in the eardrum by means of a tissue graft).

If there is hearing loss the doctor may suggest a stapedectomy (replacement of the stapes (stirrup) with a prosthesis).

Questions

What is causing the problem?

Is there significant damage to the bones or nerves?

Can this be effectively treated with antibiotics?

Can this be effectively treated without antibiotics?

Is surgery necessary?

What is it called?

How will the procedure be performed?

What are the risks?

What benefits and degree of success can be expected?