Local conditions of the tympanic membrane (鼓膜的局部疾病)

Bullous myringitis
Aetiology:
An influenza virus infection of the tympanic membrane and deep external meatus, often associated with an acute otitis media.

Clinical features:
Presents as otalgia, deafness and serosanguinous otorrhoea. Haemorrhagic bullae are seen on otoscopy. Secondary bacterial infection can occur with purulent otorrhoea leading to otitis externa.

Management:
Treat with analgesics; local and systemic antibiotics for secondary bacterial infection.


Tympanosclerosis
Aetiology:
Deposits of collagen beneath the mucosa of the tympanic membrane and middle ear following otitis media or middle ear surgery, particularly grommet insertion.

Clinical features:
Tympanosclerosis is mostly asymptomatic. Deposits are visible as white chalk patches in the tympanic membrane. Middle ear deposits may cause conductive deafness by ossicular fixation.

Management:
None if asymptomatic. Ossiculoplasty may be required for conductive deafness.