Otitis Media with Effusion / Glue Ear
Otitis media with effusion (OME) is one form of otitis media (the others being acute otitis media and chronic suppurative otitis media).
It is a disease predominantly of children. This page described it in some detail and outlines management options.
Catarrhal, exudative, serous, seromucinous, secretory and non-suppurative otitis media are all terms that are used to describe the condition (rather confusingly). The image shows OME of the left ear.
Central to the condition is pathology of the Eustachian tube. This tube, which runs from the nasopharynx to the middle ear is responsible for maintaining atmospheric air pressure within the middle ear.
The cause of Eustachian tube dysfunction varies but in general it is associated with nasopharyngeal infection (usually within the adenoids) and infective rhinitis. Note that it is not the size of the adenoid that is relevant but its state of health.
In adults unilateral glue ear may be associated with nasopharyngeal carcinoma (especially in patients of Chinese origin).
The prevalence of glue ear is highest in children (40% at two years) and steadily falls so that is uncommon in teenagers (1% at age 11).
It is also higher in winter, boys, cleft palate, Down's syndrome, bottle fed babies and in children who's parents smoke.
Generally glue ear resolves spontaneously. Over a three month period 50% of children with glue ear will resolve. Ultimately 90% will settle without treatment.
Hearing loss is the major feature and this leads to:
1. Educational delay
2. Speech problems
3. Emotional delay
4. Intellectual delay
Children may be disruptive or withdrawn. Any of these features in a child could mean hearing loss.
Fleeting otalgia may occur in some.
Disequilibrium is a less common feature. It is minor and parents often say their child is clumsy. This resolves with the effusion.
Glue ear also predisposes to recurring acute suppurative otitis media.
Clinical examination reveals a middle ear effusion in most cases (see image above). As the disease tends to come and go the patient may have no signs when seen. When present the drum looks dull and has some retraction. The drum may appear yellow or creamy. It is immobile on pneumatic otoscopy. Occasionally air bubbles can be seen.
As usual a thorough clinical history and examination often give the diagnosis but it is essential to assess the hearing loss with an audiogram together with tympanography. The audiogram may show a conductive hearing loss and the tympanogram will be flat or may be peaked at negative middle ear pressure.
1 Watchful waiting
3 Grommets and adenoidectomy
4 Hearing aid
Treatment is guided by symptoms. Some children with glue ear have no or minimal hearing loss. In such cases nothing is required except follow-up of their condition.
Other children are affected by their glue and suffer some or all of the features listed in Clinical features above. If this is the case some active treatment may be necessary.
In such cases an initial period of three months 'watchful waiting' is recommended. During this time 50% of children with glue ear will get better.
If it does not, the patient will usually be offered grommet insertion or grommet insertion with adenoidectomy (which is slightly more successful but has more potential complications).
If the child is less than 3.5 years then grommets alone are the best choice as there is little evidence that adenoidectomy is beneficial before this. Between 3.5 and 7 years is the best time for combined grommets and adenoidectomy.
Tonsillectomy has no place in the management of glue ear alone.
In some cases a hearing aid is a good option for treating the hearing loss but it does nothing to cure the glue ear. Nonetheless, in patients who decline surgery, in cases where surgery is difficult due to a narrow ear canal (Down's Syndrome), and in severe recurring cases (e.g. cleft palate patients), they play a useful role.
Grommet insertion is a common operation for children. In general, it is safe and effective but like all operations there may be complications.
These are listed below.
Complications of anaesthetic
Grommet insertion is performed under general anaesthesia in children
10% of ears with grommets discharge. This is usually curable with a short course of ear drops but rarely the grommet may have to be removed
in 1-2%, a permanent hole may remain in the ear drum after the grommet falls out (6-9 months after insertion).
Blockage of the grommet
Around 1:20 grommets become blocked and stop functioning
A chalky deposit is sometimes found in the ear drum after the grommet has come out. It is of no relevance usually.
Not really a complication but sometimes the grommet doesn't stay in long enough to allow resolution of the problem. Further grommets are required in about 20%.
Below is a schematic diagram of a grommet seen from the side and above.
The image below above show the position of the myringotomy (an incision placed in the ear drum) and the appearance after grommet insertion.
Grommets are ventilation tubes that are placed in the tympanic membrane to hold it open.
1. First a radial incision called a myringotomy is placed in the anteroinferior portion of the ear drum.
2. The glue is aspirated
3. A grommet is placed in the myringotomy to hold it open. For ease of placement the flange is inserted first. When in place, the drum fits snugly around the waist of the grommet.
This image is a cross-section of the grommet sitting through the ear drum.
Below is a clinical picture of the grommet in place. Note that in the illustration below the grommet has been placed inferiorly and anteriorly. The picture is slightly rotated anticlockwise.