cold caloric irrigation, a procedure for testing the integrity of brainstem function. It is carried out by irrigating the external auditory canal of the patient with a cold saline solution while the head is flexed at approximately 30 degrees, after checking the patency of the ear canal. The stimulus results in jerky but regular eye movements (nystagmus) in a normal patient. Absence of the reaction may be a sign of a lesion at the pontine level of the brainstem. Also called caloric test.
