Vestibulo-ocular Reflex

Also sometimes called caloric reflex, because a stimulation is based on pouring of cold or warm water into the ear. It is better to put patient´s head a slight reclining, because we want to influent especially lateral semicircular tubule of an inner ear. A small amount of water flow induces movement of endolymph.

Test can be sometimes false-positive if there is any other diasease of inner ear. Normally we react just a little bit, because nystagmus in healthy people corrects the eyes movements. There is one special rule for direction of nystagmus: "Cold opposite, warm same (COWS)", which means that cold water pouring into the left ear leads to eye movement to the left and a direction of the nystagmus is on the right (opposite side). It is the same for the second side – pouring of warm water into the left ear leads to eye movement to the right and a direction of the nystagmus is on the left (same side).

Attention! Do not confuse the direction of nystagmus (COWS rule) and the direction of motion of eyes.

Links

Related articles

• Oculo-cephalic Reflex
• Brainstem
• Cranial Nerves
• Vestibular System
• Nystagmus
• Inner Ear

Bibliography

• AMBLER, Zdeněk, et al. Klinická neurologie : část obecná. 1st edition. 2008. ISBN 978-80-7387-157-4.