1. Vestibular Autorotation Test & Rotary Chair Testing
Rotary Testing
Vestibular Autorotation Test
&
Rotary Chair Testing

2. Passive and Active Rotation
Passive– pt is moved (head or whole body) by examiner.
Halmagyi Head Thrust
Rotary Chair tests
Active—pt is asked to turn their own head.
Head Shake
VAT

3. Passive Tests Sinusoidal Acceleration Test: Velocity Step Tests:
Oscillating (left-right) in rotary chair
Freqs from 0.01 to 0.64 Hz
Peak angular velocities 50° per sec
Velocity Step Tests:
Sudden Accelerations (to left or right)
Of 100° per sec for 1 second
Responses recorded for following minute, or so.

4. Vestibular Autorotation Test (VAT)
“no” & “yes” gestures in time with metronome
Frequencies from 0.5 to 6 Hz over 18 seconds
While pt. fixates visually
Head motion recorded by accelerometer
Eye motion recorded via video or electrodes

5. Head Shaking Test Pt shakes head for 20 seconds
With Frenzel lenses in dark room
Look for post-shaking nystagmus

6. Measures from Rotational Tests
Gain: Ratio of eye velocity to head velocity
Phase: (in SAT/VAT) lag between head and eye movements (away from 180°)
Symmetry: Ratio of rightward to leftward eye velocity.
Time Constant: (in Vel. Step) time taken for eye velocity to decline to 37% of peak value.

7. VAT Gain and Phase Measures

8. Dynamic Visual Acuity Test
Visual Acuity—discrimination of shapes of different sizes
during active head movement.
Packaged systems
/ Snellen Chart