How is labyrinthitis diagnosed?

Your doctor may conduct the following when diagnosing an inner ear infection (labyrinthitis):

A physical exam

A physical exam will help your doctor to determine the cause of your condition based on your symptoms. Here, he/she will use an otoscope, which is a lighted examination instrument to look into your throat, nasal passage and ears. He/she will also use a stethoscope to listen to your breathing, placing this on your upper back and chest areas.

Pneumatic otoscope

This is an instrument that allows your doctor to get a good look into the ear and determine whether fluid is present behind your eardrum. The instrument sends a puff of air against your eardrum, this normally results in the eardrum moving. If it does not move, or only moves a little bit, your doctor will conclude that there is fluid present in the middle ear.

Eye movement test

Your doctor will conduct a physical examination as a part of the diagnosis. There are a number of other tests that he or she may perform, one of these is an examination of your eye movements to aid in detecting acquired nystagmus as this may be caused by an inner ear infection. Nystagmus refers to a condition that leads to involuntary eye movements (oscillation) that may affect or limit your vision.

Vertigo tests

The Dix-Hallpike test, also known as the Nylen-Barany test, is a therapeutic means of treatment that also tests for vertigo, a common symptom of an inner ear infection.  Your doctor will assess whether you are suffering from vertigo when performing certain head movements. During this test, your doctor will also look for any involuntary eye movements associated with nystagmus. From this, your doctor will be able to detect if the vertigo experienced is central (denoting an issue in the brain) or peripheral (denoting an issue with the inner ear).

Your doctor may also ask you to perform a series of movements known as the Epley Manoeuvre. The Dix-Hallpike test and Epley Manoeuvre are used to test for and treat benign paroxysmal positional vertigo (BPPV), a condition that is associated with issues of the inner ear. 

A doctor may perform a test known as the Romberg test to assess your balance which may be affected as a result of an inner ear infection. For this test, you will be asked to stand with your feet together, and hands at your sides and your eyes open.  You will then be asked to maintain that posture with your eyes closed, from here, your doctor will monitor you for a full minute to determine whether you experience a loss of balance during this time.  If you sway or fall while your eyes are closed (don’t worry, someone will be there to catch you if this happens), this is considered a positive Romberg sign and an indication that vestibular function is affected by the infection.

The above-mentioned tests for balance may overlap with one another and are mainly used to detect BPPV (a sign of vertigo).

Additional tests

Additional tests may be performed if your doctor is unable to give an accurate diagnosis or if the condition does not improve through treatment.

These tests can include undergoing the following:

• Taking blood tests in which a sample of your blood will be sent to a lab for testing to see if another condition may be the underlying issue.
• Recording cranial structural images of your head through an MRI (magnetic resonance imaging) or CT (computerised tomography) scan.
• Having an EEG (electroencephalogram) done to examine your brain waves.
• Having an ENG (electronystagmography) done in order to test your eye movement.
• Completing a hearing test known as acoustic reflectometry. This measures how much the sound emitted from a specialised device is then reflected from the eardrum, this basically indirectly measures the fluids inside the middle ear. This test uses the pneumatic otoscope.