|Normal ear structures|
The term otitis media means that there is inflammation of the middle ear. On the diagram above, this is the space between the external auditory canal and the inner ear (which contains the snail like cochlea). Otitis media can be associated with an infection or be sterile. In the first case, otitis media is usually caused by bacteria that migrate into the middle ear via the Eustachian tube. Occasionally otitis media may be caused by fungi (Aspergillus or Candida) or other pathogens, such as the herpes virus. In this situation, usually either there is a problem with immune function or (there is a hole (perforation) in the ear drum. Persons with diabetes are particularly susceptible to unusual pathogens such as pseudomonas. In underdeveloped parts of the world, tuberculosis should be considered (Mongkolrattanothai et al. 2003).
Sterile otitis media is usually called serous otitis media, or "SOM". The serous variety of otitis media is usually not painful. There is usually a clear or straw colored fluid behind the ear drum. The serous variety is often attributed to allergy but may also occur from numerous other potential sources including radiation treatment (Young and Lu, 2001; Young et al, 2004) or virus (Sade et al, 2003). Serous otitis media may be associated with both hearing loss and vertigo.
Chronic otitis media (COM) is defined as a long-lasting otitis media. COM may be associated with a chronically draining ear, mastoiditis, and cholesteatoma.
A chronically draining ear includes both COM as well as chronic external otitis.
Otitis media is usually diagnosed by the combination of symptoms (ear pain and reduced hearing), and direct observation of an inflamed ear drum with fluid behind it. There is usually fever too. Acutely, in uncomplicated cases, while a thorough examination is necessary, no additional testing is usually required. Certain types of ENT specialists, "otologists", are especially good at making these diagnoses and seeing one of these doctors early on may make it possible to avoid unnecessary testing.
Hearing in otitis media is generally reduced in a "conductive" pattern, to a modest amount (20-50 dB). More details about hearing loss can be found here. Hearing testing is often done to be sure that the condition is improving. The fluid behind the eardrum is associated with immobility of the ear drum as well as a "flat" tympanometer trace. Tympanometry is a test done generally when the hearing is tested.
X-rays, CT scans, or MRI scans are often helpful in the diagnosis chronic otitis media, in order to rule out a cholesteatoma. A lumbar puncture may be necessary in persons in whom meningitis is suspected.
We advise against putting in drops containing alcohol or an ototoxic antibiotic if one is unsure as to the status of the tympanic membrane (ear drum). If the TM is broken, the drops may get into the middle ear and cause hearing loss, dizziness or or severe pain.
Otitis media may spread to the mastoid sinus (which lies behind the ear), causing a much more serious infection. This is particularly dangerous in persons with impaired immune systems. Otitis media may also occasionally cause a meningitis. Severe or chronic otitis media may permanently affect hearing (Papp et al, 2003) and be associated with dizziness. The hearing loss is typically more severe at high frequencies. The ear drum may perforate (break). In children, otitis media can reduce hearing at a time that is critical for speech and language development. It is very possible for a child to have chronically reduced hearing, without much pain.
Hearing is typically reduced and there is ear pain. Adults generally are impacted similarly.
According to Dobrianskyi et al (2017), "A total of 98 patients with chronic otorrhea and 60 with dry tympanic membrane perforation were evaluated. A correlation between sensorineural hearing loss and chronic otorrhea was observed when compared with both contralateral normal ears and dry perforated ears of other patients. No relationship between hearing loss and the duration of suppuration or cholesteatoma was found. Sensorineural hearing loss occurs in ears with chronic otorrhea. The duration of otorrhea and the etiology of suppuration did not influence the hearing loss."