The optokinetic response examines the pursuit and saccadic systems separately, together with their interconnecting pathway, by asking the patient to look at a revolving drum with images - white lines on a black surface - held a short distance from the eyes.
The moving targets should not be too fast - not greater than 30/sec - as pursuit must be allowed to occur.
Optokinetic nystagmus is an involuntary reflex and cannot be voluntarily damped unless the patient can look past the testing drum.
A downgoing optokinetic stimulus is the best way of inducing convergence retraction nystagmus in Parinaud's syndrome.
Last reviewed 01/2018