Introduction
Otitis media with effusion (OME) is a condition that most commonly affects children, often termed “glue ear“.
OME is caused by the build-up of a viscous inflammatory fluid within the middle ear, resulting in a conductive hearing impairment.
In this article, we shall look at the aetiology, clinical features and management of otitis media with effusion.
Aetiology
In children, otitis media with effusion is usually caused by a combination of chronic inflammatory changes and Eustachian tube dysfunction.
The anatomy of the Eustachian tube in younger children is immature, typically short, straight, and wide (only becoming more oblique as the child develops), therefore infection is more likely.
The condition is less common in adults, however will occur if there is any blockage of the Eustachian tube, either from infective causes or from occlusive masses*.
*Consequently, any new case of unilateral OME in an adult should be investigated as a ‘red flag’ for a malignant underlying cause
Risk Factors
The main risk factors for otitis media with effusion include:
- Bottle fed
- Paternal smoking
- Atopy (e.g eczema, asthma)
- Genetic disorders
- Mucociliary disorders, such as Cystic Fibrosis or Primary Ciliary Dyskinesia
- Craniofacial disorders, such as Downs Syndrome
Clinical Features
The most common clinical feature of otitis media with effusion is difficulty hearing* (affecting one or both ears) and representing a conductive hearing loss.
There may be a sensation of pressure inside the ear that may be accompanied by ‘popping’ or ‘crackling’ noises. Less commonly, the patient can also experience disequilibrium and vertigo.
On examination, the tympanic membrane will appear dull (Fig. 2) and the light reflex will be lost, indicating fluid in the middle ear. There may also be a bubble seen behind the TM. The external ear will be normal.
*In young children this may be noticed as difficulty with attention at school or poor speech and language development
Investigations
In most cases, otitis media with effusion is diagnosed clinically on the basis of history and otoscopy findings.
Both pure tone audiometry and tympanometry are nearly always performed in such cases, which will reveal a conductive hearing loss and reduced membrane compliance (a type B tracing) respectively.
In adults, a full ENT examination should be performed, including flexible nasoendoscopy (to exclude a post-nasal space mass).
Management
Otitis media with effusion in children can be managed in an outpatient setting. Approximately 50% of cases will resolve within 3 months; hence many cases are managed by ‘active surveillance’.
If no resolution is seen after 3 months, the management options can be divided into surgical and non-surgical:
- Non-surgical – hearing aid insertion
- Surgical – myringotomy and grommet insertion
In the UK, NICE guidance recommends the insertion of Grommets* for those with > 3 months of bilateral OME and hearing level in better ear < 25-30dBHL
Any child with persistent disease and multiple grommet insertion should be considered for potential adenoidectomy.
*Certain cases, such as patients with Down syndrome, first line therapy may actually be a hearing aid, as complications from grommet can be common
Key Points
- Otitis media with effusion is caused by the build-up of a viscous inflammatory fluid within the middle ear
- Risk factors for developing the condition include being bottle fed, parenteral smoking, atopy, and some genetic disorders
- Patients will have a conductive hearing loss, with the tympanic membrane appearing dull on examination
- Most cases will resolve spontaneously, however medical and surgical options are available if symptoms do not resolve within 3 months