College of Allied Health Sciences
Communication Sciences and Disorders



Description of Vestibular Assessment
Comprehensive balance evaluation
Videonystagmography (VNG) only; 1 hour
Vestibular Autorotation Testing
Dynamic Visual Acuity Test
Rotary chair only; 1 hour
Subjective Visual Vertical Test
1 ½ to 2 hours
Vestibular Evaluation Procedures

Videonystagmography (VNG)
During this testing, eye movements are recorded using infrared video cameras. The client may be asked to wear a special set of goggles or a headband. Three different stimuli are used: 1) visual stimuli in which the clients is asked to follow a lighted target visually, 2) positional stimuli in which the client is placed is different head and body positions, and 3) caloric stimuli in which warm and cool water OR warm and cool air is put into each ear. The resulting eye movements provide valuable information about the portion of the inner ear related to balance, the vestibular system. 1 to 1 ½ hours

Vestibular Autorotation Testing
During this test, eye movements and head movements are recorded while the client turns his/her head side to side or up and down. The test provides information about eye movements that occur in response to head movements. ¼ to ½ hour

Dynamic Visual Acuity Test
This test measures how well the client can see a visual target while s/he moves her/his head side to side. The test provides information about how well the vestibular system can keep the eyes on a visual target. ¼ to ½ hour


Rotary Chair
The client is asked to sit in a chair that rotates in a slow and precise manner. Visual stimuli may be presented. Eye movements are recorded using infrared video cameras. This testing evaluates the relationship between the vestibular (inner ear balance system) and the oculomotor (eye) system. 1 1/2 to 2 hours

Subjective Visual Vertical
The client is asked to watch a line of lights while the rotary chair is turning and s/he holds a dial that controls the orientation of the line. The client is asked to maintain the line as close to vertical orientation as possible. This test provides information about the function of one of the gravity sensing organs within the inner ear (i.e., the utricle). ½ hour

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