A caloric test uses differences in temperature to diagnose damage to the acoustic nerve, which is involved in hearing and balance, in the ear. The test also checks for damage to the brain stem.
This test may be used to find the cause of:
The caloric test stimulates the acoustic nerve by delivering cold or warm water or air into the ear canal. When cold water or air enters your ear and the inner ear changes temperature, it should cause fast, side-to-side eye movements called nystagmus.
During the test, the physician should observe the patient’s eyes for movement.
Patients may find the cold water or air in the ear uncomfortable. They may feel their eyes scanning back and forth during nystagmus. Vertigo and nausea can occur but last a short time. Vomiting is rare.