Glue ear

 

What is it?

Glue ear is a condition in which thick sticky fluid collects in the middle ear, causing impaired hearing. It usually affects children and is also known as:

  • Otitis media with effusion
  • Chronic secretory otitis media (CSOM)
  • Serious otitis media
  • Middle ear effusion

How does it occur?

Normally each middle ear is ventilated by the Eustachian tube, a channel running from the middle ear to the back of the nose. However fluid can accumulate if the tube is blocked or fails to function for some other reason.

 

Why does it occur?

The lining of the Eustachian tube can swell and block the drainage of the middle ear, especially in children, because:

  • The very young have frequent infections like colds and sore throats since they have yet to build up useful immunity to common viruses
  • Their Eustachian tubes have a different shape to those of adults
  • Their adenoids (lymph tissue similar to the tonsils but located at the back of the nose, where the Eustachian tubes open) are more likely to be enlarged. In fact most of the other lymphoid tissue in the body is also larger in childhood, and later shrinks as part of normal growing up

This is why glue ear, although it can affect adults, more often occurs in children. Up to 20% of children, usually between the ages of 2 to 5 years, can develop glue ear. It is more common in boys than girls, and more often occurs in winter and spring.

Other factors predisposing to glue ear include:

  • History of glue ear in a brother or sister
  • Parents who smoke
  • Allergic conditions (like hay fever, milk allergy)
  • Certain genetic abnormalities (like Down's syndrome, Turner's syndrome)
  • Abnormalities of the base of the skull or nasal bones
 

What are the symptoms?

Hearing loss is the most common symptom, and glue ear is also the most common cause of hearing loss in children. The type of hearing loss is called conductive, because sound waves are not conducted properly through the fluid.

What are the complications?

If glue ear involves both ears and persists for many months, especially before the age of three or four years, it can interfere with normal speech development. That's why it is important to detect and treat glue ear, and also why any child whose speech is delayed or abnormal should have a hearing test.

A youngster with prolonged hearing impairment may also run into problems with their social and educational development This is not surprising if they cannot hear what is said or what they are required to do.

Children with glue ear can also have repeated episodes of earache and acute ear infections (acute otitis media). In a very few cases, glue ear causes permanent damage to hearing. It can also lead very rarely to the formation of cyst-like swelling called cholesteotoma in the middle ear.

 

What tests are done?

Otoscopy

This involves looking at the eardrum with an otoscope, (a hand-held instrument GPs use) which may show bubbles of trapped fluid behind the eardrum. This is often enough to make the diagnosis. A more sophisticated otoscope, such as those used in ENT clinics, may help assess the pressures in the eardrum.

Audiometry

This may be done at the GP's surgery or by the specialist. It measures hearing across a range of frequencies and helps assess the significance of any hearing loss. How it is carried out depends very much on the age of the child and there are now newer techniques for the very young.

Tympanometry

This is a measurement to assess how well the eardrum moves in response to sound, but it does not directly measure hearing. It is a useful test even in babies under a year old.

 

What is the treatment?

Glue ear does not always need treatment. It is now known that around 50% of cases resolve on their own within 3 months, 75% within 6 months, and 90% within 12 months. But children who have complications like frequent earache, or who might be at risk of developing speech problems because their glue ear is persistent, may benefit from treatment. The decision whether or not to treat can be difficult and requires discussion between parents and doctors in each case.

The established treatment for persistent glue ear is the insertion of grommets (in one or both ears). These are tiny tubes made of Teflon which are placed under general anaesthetic into the ear drum to allow air to pass freely between the middle ear and the outside. Equalising the pressures in this way allows near-normal hearing, and the operation is usually done as a day-case.

Strictly speaking, a grommet does not drain fluid from a glue ear; the procedure actually starts with myringotomy, a small incision into the eardrum to remove as much of the viscous fluid as possible, before the grommet is inserted into the cut.

Many children who need grommets have enlarged adenoids too, so they often benefit from adenoidectomy at the same time.

 

Are there alternatives to surgery for glue ear?

The natural course of events is for fluid to come and go over a period of time and many children only have glue ear for 3 months. Instead of operating on every child with glue ear, it can therefore make sense to watch and wait. Some doctors think it a good idea to place a child with glue ear on the waiting-list for grommets and then see what happens by the time they reach the top of the list. Whether this is done or not, the watching part is essential to see whether things are improving.

There are some experts who advocate the use of long courses of antibiotics (2 to 4 weeks or more) to treat glue ear; this may improve the outlook although does not necessarily avoid the need for grommets, especially if both ears are involved. Recent research has looked at the option of giving a dose of steroids as well as antibiotics in the treatment of glue ear, but results so far are not encouraging.

The use of Otovent can also prove helpful. This is a type of balloon which children are encouraged to inflate using their nose rather than their mouth. There is some evidence that this encourages an improvement in Eustachian tube function and diminishes the need for grommets.

Some ENT specialists recommend decongestant medicines containing pseudoephedrine. These are sometimes worth trying, although they can have side-effects in both children and adults.

Hearing aids can be used to overcome the hearing loss associated with glue ear and it may help children both at home and at school. However this treatment is unlikely to be popular with either children or their parents if another more fundamental solution (like grommets) exists.

So, although there are many possibilities for treating glue ear, the main options lie between surgery (grommets with or without adenoidectomy) and watchful waiting (and then some children will need surgery after all).

 

Are lifestyle changes are advisable after grommets?

At one time, almost all children with grommets were forbidden to swim, but this has changed. Many specialists now think swimming is safe with grommets, but that diving is not (a reasonable compromise which avoids water being driven into the middle ear under pressure). However in each case the ENT surgeon should give specific advice.

Grommets usually stay in for about a year, at which point they fall out (often into the child's bed) or are removed. The eardrum usually heals quickly after this. If grommets fall out prematurely, or glue ear recurs, a repeat grommet insertion may be advised. Again, this depends on the individual case, and follow-up is essential after every grommet operation. Grommets should not be left in longer than necessary because this sometimes leads to permanent perforation of the eardrum.

 

Where can I obtain further information?

Royal National Institute for Deaf People

19-23 Featherstone Street
London
EC1Y 8SL
Telephone: 0870 6050123 (Voice)
Email: helpline@rnid.org.uk
Website: www.rnid.org.uk