Rotatory chair testing is a component of the vestibular test battery. It has primarily been used for analyzing the vestibulo-ocular reflex (VOR) during angular stimulation of the horizontal semicircular canals.
Standard rotational testing involves Sinusoidal Harmonic Acceleration test (SHAT) and Velocity-step (VST) for evaluation of the horizontal semicircular canal function. SHAT presents stimuli at several sinusoidal frequencies where gain, phase and symmetry of eye movements are analyzed, while VST provides constant velocity stimulation after rapid-onset acceleration followed by rapid deceleration and time constant is recorded.
Rotatory chair has many clinical applications. It is considered the “gold standard" in the evaluation of bilateral vestibular lesions and can be used to assess vestibular central compensation following acute vestibular dysfunction.
The VOR changes as a function of age is a controversial topic and studies of rotatory chair SHAT and VST are limited in literature with variable normal ranges for the test parameters from lab to lab.