Alternative Names: Secretory otitis media; otitis media with effusion; glue ear.
Definition: Among otolaryngologists, who are specialists in the management of ear disease, chronic otitis media has a distinct connotation. By definition it is a perforated eardrum with intermittent or persistent infected ear drainage. The term chronic otitis media, however, has taken on an alternative meaning and has been used to refer to asymptomatic fluid behind the eardrum which has failed to resolve.
What Is Going on in My Body? The anatomy and physiology are identical to that discussed under acute otitis media. In otitis media with effusion (secretory otitis media), there is persistent fluid which is not resolving spontaneously. From a number of studies, approximately 90% of children who develop fluid behind the eardrum, regardless of its cause, will have it resolve in approximately three months. In otitis media with effusion, part of the reason the fluid fails to resolve is continued swelling and obstruction of the eustachian tube and also continued inflammation of the lining of the middle ear space. The reasons for the continued inflammation vary. When the fluid has been cultured for bacteria, approximately a third of the time it contains organisms commonly associated with acute otitis media, such as Streptococcus pneumonia, non-typable hemophilus, and Moraxella catarrhalis. In another third of patients other bacteria are present that usually are not associated with acute otitis media, and in the other third the fluid collections are sterile. What is thought to occur is that the presence of bacteria or products from their breakdown by the immune system, in addition to some of the products released by the immune system during the infection, cause a continued inflammatory response behind the eardrum. Part of the response in inflamed mucous membrane is to make an increased volume of a more viscous solution. The mucosal lining of the eustachian tube also becomes swollen and obstructive.
The mechanism of chronic otitis media with a perforated eardrum and ear drainage is somewhat different than that of otitis media with effusion, although eustachian tube problems may also exist. In this condition there is usually inflammation in the mastoid or in the channel between the middle ear and mastoid which is a result of chronic bacterial infection. These bacteria are usually different from that causing acute ear infections and often consist of Staphylococcus aureus, Pseudomonas aeruginosa, or a class of bacteria called anaerobes which require low-oxygen environments to thrive.
What Are the Signs and Symptoms? In otitis media with effusion there is fluid present behind the tympanic membrane which often has very few, if any, symptoms. The main symptom is conductive hearing loss. If the patient is old enough, they may complain that their ear feels plugged or full. There is often no pain or fever as often is seen with the more acute form of infection. In children the signs of hearing loss may be quite difficult to determine. Even deaf children will babble until the age of six months, but the babbling typically stops. If the child “ignores” the parent, sits close to the TV, needs to have words repeated, says “what” frequently, or is not progressing in their speech, hearing loss may exist. It is usually mild in nature, and its effect upon speech is quite subtle. In these milder forms of hearing loss, low-power sounds, such as F, S, or TH are the first to be inaccurately articulated. In otitis media with effusion different kinds of fluid can be present behind the eardrum. It ranges anywhere from the yellow-colored, more liquid type all the way to thick, white, rubber-cement-like material. The more viscous types of fluid are usually a result of more significant degrees of middle ear mucous membrane inflammation.
In an individual with chronic otitis media there will be a perforation in the tympanic membrane. Through the perforation the mucous membrane lining of the middle ear can be examined. There may be a small amount of drainage behind the eardrum, and the lining blood vessels may be more prominent, or the lining itself might be thicker and more red than usual. Varying types of fluid may be present in the ear canal. Sometimes it may have a watery, slightly mucous consistency all the way to frank yellow-green, foul-smelling discharge. These individuals often respond to antibiotics, only to relapse with their drainage. They may often complain of hearing loss. As opposed to acute mastoiditis, there is usually no pain, swelling of the skin overlying the mastoid, or fever.
What Are the Causes and Risks? The causes of otitis media with effusion are almost identical to those which cause acute otitis media (see acute otitis media). From large studies of children in daycare centers, up to 70% of them may have fluid behind their eardrums at some point during the course of a year. Usually 90% of the time the fluid resolves spontaneously without treatment. Other causes include chronic sinusitis, chronic or acute allergy, craniofacial abnormalities, or palate dysfunctions. Malignancies around the eustachian tube can give rise to secretory otitis media. Even though these are extraordinarily rare, asymptomatic fluid behind just one eardrum can indicate a cancer. This is particularly true in adults, and therefore, unilateral otitis media with effusion in adults is assumed to be caused by malignancy until proven otherwise.
The causes of chronic otitis media are not only eustachian tube dysfunction but also ongoing low-grade infection within the mastoid. Once again individuals who have eustachian tube dysfunction, regardless of the mechanism, are at a greater risk. These causes would include individuals with craniofacial or palatal abnormalities, Down’s syndrome, individuals of American Eskimo or Indian descent, slag burns to the tympanic membrane, and patulous eustachian tube.
How to Prevent the Disease: Preventing otitis media with effusion would depend upon preventing the diseases that lead to it, particularly viral upper respiratory illness. This factor and others are discussed in detail under acute otitis media.
Preventing chronic otitis media once again depends upon improving overall eustachian tube function. Unfortunately, even with our great technological strides, there is still not a definite test of eustachian tube function. As chronic mastoiditis may be the result of poorly or inadequately treated acute otitis, it is imperative that children with acute otitis who need antibiotics have not only appropriate therapy, but the therapy must be completed.
How Is It Diagnosed? Otitis media with effusion is diagnosed by three different means. The first method is physical examination, the second is with tympanometry, and the third is with audiometry. Fluid behind the eardrum and poor tympanic membrane movement are present upon examination. Tympanometry is the measure of the amount of eardrum mobility, and in otitis media with effusion it is often severely impaired, which manifests as a flat line on the tympanogram instead of a peak pattern. On hearing testing a conductive hearing loss will be present of varying degree. There is usually no role for CT scans of the mastoid.
In chronic otitis media, diagnosis employs physical examination. On examination there is a perforation in the tympanic membrane and infected material visualized in the middle ear space through the perforation and/or in the external ear canal. Culture of the infected material to try to determine the specific bacteria and to which antibiotics they are sensitive can help guide treatment. Hearing tests are obtained to document the type and degree of hearing loss, and if surgery is contemplated or the diagnosis is not absolutely certain, then a CT scan of the mastoid and temporal bone can yield useful information.
What Are the Long-Term Effects? In otitis media with effusion, the long-term effects depend upon whether or not hearing is restored by draining the fluid, usually with ventilation tubes. In children who have undiagnosed fluid and subsequent conductive hearing loss, speech and learning delays are often present. If the inflammation that gives rise to the fluid behind the tympanic membrane is unresolved, then tympanosclerosis can occur. Tympanosclerosis is scarring of the tympanic membrane or mucous membrane of the middle ear. It is quite firm and in some cases actually calcifies. As a consequence, it can impair eardrum or ossicle (middle ear bone) movement, with a resultant hearing loss. Surgical correction of hearing loss from tympanosclerosis is typically less successful. Some individuals with untreated otitis media with effusion will start to develop retraction pockets of the tympanic membrane because of the constant negative pressure behind the eardrum. These pockets arising from the eardrum begin to push into the middle ear space and can erode the bones for hearing, with hearing loss, and if they get particularly large or infected, can impair their ability to shed the skin forming on their surface. If this skin starts to accumulate within the pocket, it can form a cholesteatoma (see benign ear cyst or tumor). In some patients an adhesive process can develop whereby the drum adheres to the bones for hearing and other middle ear structures. If eustachian tube function then improves and the fluid resolves, the drum is often left adherent. As long as eustachian tube function continues to remain normal, then no further sequelae occur; but if the eustachian tube function is inadequate, then the drum can continue to be pulled into the middle ear space, with erosion of the bones for hearing, perforation, or formation of a cholesteatoma.
The long-term effects of chronic otitis media relate mostly to the infectious process. Tympanosclerosis around the ossicles and drum can occur. Because of the perforation in the eardrum, adhesive otitis may not develop, or if it has already developed, it often will stabilize. The main concern is the damage to the conductive mechanism for hearing, and because of the ongoing infection, these individuals may develop an impairment of hearing nerve function. The greatest concern relates to the infectious process in the mastoid. If chronic otitis media occurs at a fairly young age, mastoid development will be impaired. Chronic otitis media also places the individual at risk for intracranial complications, such as brain abscess and meningitis.
AM I PUTTING OTHERS AT RISK? No.
What Are the Treatments? For otitis media with effusion that does not respond to antibiotics and oral steroids, ventilation tubes are effective.
In the treatment for chronic otitis media the most important goal is creation of a safe ear. This involves repairing the tympanic membrane and removing any diseased or infected tissue in the mastoid and middle ear. Hearing in surgery for chronic ear disease is a secondary goal. In the individual with chronic otitis media, removal of the diseased lining within the mastoid and middle ear and simultaneous restoration of the air channel between the mastoid and middle ear is performed via mastoidectomy. At the same setting the eardrum perforation is repaired, and if there are abnormalities in the bones for hearing, these are simultaneously reconstructed.
What Are the Side Effects to the Treatments? Ventilation tubes have fortunately few, if any, side effects. Persistent perforation occurs in approximately 2 to 3% of patients once the tubes extrude. Average duration of tube life span is 6 to 12 months. Another potential side effect of the tube placement would be the need for another set of tubes, which is necessary in approximately 20% of children. Other complications of tube placement can occur, although they are very rare, such as nerve deafness and cholesteatoma.
The side effects to mastoidectomy would be failure to completely eradicate the infection, taste disturbance on that side of the tongue, incomplete restoration of hearing, nerve deafness, vertigo, facial nerve injury, or breakdown of the repaired tympanic membrane. If synthetic materials are used to restore the chain of bones for hearing, these can become dislodged or fail.
What Happens After Treatment? For otitis media with effusion, hearing is usually restored quite rapidly. There may be some brief, continued drainage through the ventilation tube. After tubes are placed, some care needs to be taken regarding prevention of contamination of the middle ear space by bacteria. Treated, chlorinated water, such as in swimming pools or out of the tap, will infrequently penetrate the middle ear space through the ventilation tube. Often antibiotic ear drops are used after a child swims or if there is some concern that they have gotten water in their ears. The risk of developing an infection with a tube in place is highest if shampoo or soapy bath water enters the middle ear through the tube. Usually there is a high concentration of intestinal bacteria once the child has bathed, and this water, because of the soap, much more readily enters the middle ear. If an individual with ventilation tubes decides to dive or swim deeply under water, it is prudent to wear custom-made ear plugs along with neoprene headbands.
In most individuals, after surgical intervention for chronic otitis media, healing is complete within two to three months. If there has been successful treatment of the process, there will be no further infections, and an improvement in hearing. However, if the mastoid infection continues, the tympanic membrane will re-perforate, the drum will be retracted, or fluid will re-develop behind the eardrum.
How Do I Monitor the Disease? As the main complaint in otitis media with effusion is hearing loss, diminished audition after an upper respiratory tract infection or treated acute ear infection should prompt a visit to their physician. Continued drainage after tube placement or failure to improve the hearing needs to be investigated.
Monitoring the disease in chronic otitis media depends upon the presence of ear drainage. Any individual with intermittent or persisting ear drainage, especially if it is associated with hearing loss or in whom a complication develops, such as dizziness, facial paralysis, or intracranial problems, needs to be evaluated immediately.