Diagnostic tests
Diagnosis of vestibular disorders
For reasons of better readability, the generic masculine is used and the simultaneous use of the language forms male, female and diverse (m/f/d) is dispensed with. Unless otherwise indicated, the personal designations used in this patient information refer to all genders.

Your GP will first try to rule out so-called "red flags" based on your medical history. In medicine, this term refers to warning signs or symptoms that may indicate a serious or potentially life-threatening illness. If your doctor detects such warning signs, he or she will order further examinations such as a computer tomography (CT) scan, magnetic resonance imaging (MRI), ultrasound, electrocardiogram (ECG), blood tests or a referral to a neurologist to rule out serious illnesses.
It is important to emphasize that such examinations are often performed without the presence of red flags in order to reassure the patient and alleviate unnecessary concerns. Once potentially dangerous conditions have been ruled out, the inner ear should be examined in more detail using specific tests. These tests and examinations are presented below.
Summary
- Exclusion of red flags: The family doctor initially rules out serious illnesses.
- Hearing tests: Testing of the hearing (tympanometry, stapedius reflex) for vestibular disorders.
- Balance tests: Gans SOP test and posturography to assess balance.
- Position tests: Position tests for the diagnosis of positional vertigo (BPLS).
- Vestibular function tests: VNG, vKIT and VEMP to examine the vestibular system.
1. hearing tests
Not all vestibular disorders affect hearing. However, some can affect hearing and balance at the same time. For this reason, patients complaining of dizziness or balance problems often undergo extensive hearing tests. These include:
- Tympanometry: Measures the mobility of the eardrum and the pressure in the middle ear
- Stapedius reflex test: This test measures the reflex of the stapedius muscle, which reacts to loud noises and protects the hearing.
- Measurement of otoacoustic emissions (OAE): OAEs are echoes from the inner ear generated by outer hair cells.
The resulting test patterns may reveal problems with the vestibular system. A normal hearing test is informative in itself.
2. balance tests
The Gans Sensory Organizational Performance (SOP) test and Computerized Dynamic Posturography (CDP) are different methods for assessing general balance performance under different conditions. While some diagnostic centers use the Gans SOP test, others use CDP.
Although neither test can provide a specific diagnosis on its own, certain patterns of results can be recognized which, in combination with other vestibular tests, can provide indications of different types of vestibular disorders.
3. positional samples for benign paroxysmal positional vertigo
GPs/emergency doctors and IVRT® Dizziness and Vestibular Therapists and routinely perform the Dix-Hallpike test and/or the Supine Roll test for benign paroxysmal positional vertigo (BPLS). These are positional tests that determine whether your dizziness is triggered or exacerbated by certain head movements.
The patient is often fitted with special glasses in order to observe the eye movements more closely and find out which semicircular canal is affected. The glasses can be used to detect involuntary, rapid eye movements (nystagmus).
4. vestibular function tests
Clinical tests of vestibular function assess whether there are problems with the vestibular structures of the inner ear (vestibular system) and/or their connections to our eyes, central nervous system and proprioceptive system (sense of self-motion and body position). These complex structures are located next to the hearing structure of the inner ear (the cochlea).
The vestibular system consists of 5 sensors in each ear: three fluid-filled semicircular canals and 2 macular organs (utriculus and sacculus). There are tests that can be used to examine all 10 of these sensors.
How can I have my vestibular function tested?
To test your vestibular function, you would need to see an ENT specialist or neurologist who specializes in dizziness. Common tests include (4.1.) videonystagmography (VNG), (4.1.3.) caloric testing, (4.2.) the video head impulse test (vKIT) and (4.3.) the VEMP ("vestibular evoked myogenic potentials") test, all of which check the function of the vestibular system. These tests are presented in sequence below.
A complete examination of the vestibular system, which includes all the examinations mentioned, can take up to 3 or 4 hours or be spread over several appointments.
With the exception of the caloric test, the diagnostic tests cause little or no dizziness. The caloric test causes temporary dizziness and sometimes nausea.
There is no need to worry if all tests show normal results. On the contrary: normal results are valuable and help to narrow down the cause of your symptoms. They don't mean that you don't know what's wrong. While future tests may be able to more accurately show how your vestibular system responds to gravity, current procedures are not always sensitive enough to detect disturbances in all areas of the vestibular system. So normal test results do not rule out a problem.
VNG tests involve wearing glasses with an infrared camera that records eye movements. VNG tests can reveal an abnormal, involuntary, repetitive movement of the eyes ("nystagmus"), which may indicate a disorder of the vestibular system. There are 3 different tests that are performed with VNG glasses:
Oculomotor tests evaluate the brain's ability to perform and control voluntary eye movements. Abnormal results may indicate problems in the brainstem and/or cerebellum. Most people do not experience dizziness or nausea with this test. Oculomotor testing can also be performed without VNG by IVRT® Dizziness and Vestibular Therapists.
These tests are performed in a variety of positions, including those that are known to cause dizziness in patients. VNG positional tests can help detect benign paroxysmal positional vertigo (BPLS), a common balance disorder. If a patient suffers from BPLS, the test may produce a brief episode of vertigo. This can be very helpful in diagnosing BPLS. These tests can also be performed without VNG by IVRT® Dizziness and Vestibular Therapists.
Also known as the "water test", this vestibular function test examines the lateral (horizontal) semicircular canals. The left and right ear are tested in turn by pouring warm or cold water into the ear for 30 seconds while the patient is wearing the VNG goggles. A certain amount of pressure may be felt in the ear canal. The temperature of the water is transferred to the horizontal semicircular canal and warms or cools the inner ear fluid, which briefly changes the fluid density in the vestibular system. This either temporarily activates or inhibits the vestibular system, often resulting in a brief sensation of vertigo. It is recommended to examine both ears with both warm and cold irrigation. Very rarely, ice water is used to find out whether the examined semicircular canal is still functional at all. Performing this test with air instead of water is not reliable and is therefore not recommended.
Examination of the vestibulo-ocular reflex (VOR) is crucial for the diagnosis of functional disorders of the vestibular system. The VOR makes it possible to maintain a stable image on the retina despite rapid head movements by controlling the eyes in the opposite direction to the head movement. Various tests, such as the video head impulse test (vKIT) and the suppression head impulse test (SHIMP), check the function of this reflex.
One task of the vestibular system is to stabilize the eyes. The vestibulo-ocular reflex (VOR) enables us to keep our gaze stable while we move our head. The vKIT tests how the VOR works.
In this test, the patient is asked to focus their eyes on a fixed point while the examiner turns their head quickly. In order to continue to fixate the point, the eyes must move in the opposite direction at the same angular velocity as the head. In patients with a dysfunction, the eyes follow the head movement, which requires a corrective eye jump ("a saccade") to bring the gaze back to the target. The head and eye movements are recorded using special glasses.
The vKIT test examines all 6 semicircular canals. In contrast to the caloric test, the vKIT records the reactions to very rapid head movements in the frequency range from 1 to 4 Hz. Most people do not experience dizziness or nausea during this test.
The suppression head impulse test (SHIMP) is increasingly being used together with the vKIT. While the vKIT aims to fixate a stationary point, in the SHIMP the patient follows a laser point that moves with the head movement.
People with a healthy vestibular system need to make a corrective saccade to follow the moving target. In patients with vestibular dysfunction, the eyes move together with the head, so no saccades are necessary as the target remains continuously in view. Thus, the occurrence of a saccade in the SHIMP test indicates a functioning vestibular system.
The combination of both tests provides additional information, especially in cases where vKIT results are difficult to interpret. In such cases, the SHIMP test can clarify whether the vestibular system is intact.
There are pathways that lead from the macular organs (utriculus and sacculus) in the inner ear to various muscle groups. These pathways stimulate responses that can be measured in the muscles. Currently, 2 types of muscle tests can be performed to assess the utriculus and sacculus:
The cVEMP test measures the response of the sacculus, a structure in the vestibular system, using the neck muscles. Sensors are attached to the forehead, collarbones and both sides of the neck. The sacculus is activated by loud sounds through headphones while the patient alternately tenses the neck muscles. A healthy sacculus produces a measurable response. If the response on one side differs significantly from the other, this indicates a possible disorder.
Another part of the cVEMP test lowers the volume to a level at which no response should occur (due to the thickness of the skull bone protecting the saccule). However, if the petrous bone is thinned(semicircular canal dehiscence), a response can be triggered even to softer sounds, indicating a malfunction. The cVEMP test usually takes 30 to 60 minutes and can occasionally cause a slight, brief feeling of dizziness.
The oVEMP test activates small eye muscles around and below the eyes. Sensors are attached to the collarbone, the sides of the nose and under each eye. In some test centers, a sound is played into the ear, while in others a device called a "mini-shaker" is used to activate the utriculus by tapping it firmly on the forehead.
The reaction on both sides is measured. No response on one or both sides or an asymmetrical response indicates a problem with the utriculus.
The oVEMP test can also help to detect semicircular canal dehiscence. The test takes about 30 to 60 minutes and does not cause dizziness or nausea in most people.
5. further supplementary tests to examine vestibular function
5.1 Dynamic Visual Acuity Test (DVA test for short)
As already mentioned, one of the main functions of the vestibular system is to stabilize the eyes during head movements. The DVA test measures this ability to stabilize the gaze.
Similar to the vKIT, this useful test is used to investigate changes in the VOR. In addition, the DVA test can be used to assess improvements following vestibular rehabilitation.
During the test, you are asked to look at the letter "E" on a screen and determine its orientation. The letter appears at regular intervals, each time in a different size and orientation. The test is first carried out without head movements, then with. The difference in visual acuity is then compared: The greater the difference between static (without head movement) and dynamic (with head movement) visual acuity, the more severely the VOR is impaired.
There is also a manual version of the DVA test that is performed without special medical technology. This version is used by IVRT® vertigo and vestibular therapists to detect disorders of the VOR.
5.2 Subjective visual vertical and horizontal (SVV and SVH)
The subjective visual vertical (SVV) and subjective visual horizontal (SVH) are diagnostic tests that examine the perception of spatial orientation and in particular the parts of the inner ear that are responsible for the perception of gravity (utriculus and sacculus).
In the SVV test, the patient is placed in a dark room and asked to align the projected image of a rotating line so that it is perceived as exactly vertical (SVV) or horizontal (SVH). The dark test environment minimizes visual references, so the perception of the line is highly dependent on the function of the macular organs (utriculus and sacculus) in the inner ear.
The SVV/SVH test can be used to detect disturbances in the perception of gravity, which can be caused by dysfunctions of the vestibular system or the vestibular nerve. Deviations in the alignment of the line indicate a malfunction in the macular organs, as is the case in acute vestibular neuritis or a brain stem/cerebellar infarction, for example.
What else can I do?
Where can I find a specialized IVRT® vertigo and vestibular therapist?
Vestibular rehabilitation and balance training are most effective when you follow a series of exercises tailored to your specific needs by a therapist. That's why we highly recommend our certified IVRT® therap ists.
We also offer you the opportunity to get advice from our vestibular rehabilitation experts over the phone.