[14] Otitis Media with Effusion Flashcards
What is otitis media with effusion also known as?
Glue ear
What is glue ear?
Fluid accumulation in the middle ear and mastoid cavity due to negative pressure from eustachian tube dysfunction
How common is glue ear?
The most common cause of hearing impairment in children
What are the three main functions of the eustachian tube?
- Equilibration of the pressure between the middle and external ear
- Clearance of secretions
- Protection of middle ear
What happens if eustachian tube dysfunction is persistent?
A negative pressure develops in the middle ear
How does negative pressure develop in the middle ear when there is eustachian tube dysfunction?
Absorption or diffusion of nitrogen and oxygen into the middle ear mucosal cells
What happens if the negative pressure in the middle ear is present for long enough?
A transudate is elicited from the mucosa leading to the accumulation of the serous effusion
What happens to the serous effusion as a result of the eustachian tube dysfunction?
It becomes a sessile medium ideal for proliferation of bacteria
What do most cases of glue ear in children follow?
An episode of acute otitis media
What can glue ear occur as a result of post-AOM?
- Impaired eustachian tube dysfunction
- Low-grade infection
- Chronic colonisation of adenoids
- Persistent inflammation
- Adenoidal infection or hypertrophy
How can chronic colonisation of the adenoids lead to glue ear?
Can act as a source of bacteria entering the middle-ear
What is the main cause of glue ear in adults?
Eustachian tube dysfunction
What can cause eustachian tube dysfunction in adults?
- Infection/inflammation
- Anatomical blockages
What can cause infection/inflammation leading to eustachian tube dysfunction in adults?
- Severe nasopharyngeal infection e.g. sinusitis
- Severe or chronic allergy
What can cause anatomical blockage leading to eustachian tube dysfunction in adults?
- Nasal septal deviation
- Nasopharyngeal tumour
- Radiation to head and neck following cancer treatment
- Enlarged tonsils or adenoids
- Trauma