While lying semi recumbent on a bed, dark goggles will be placed on your eyes and a small infrared camera records your eye movements. The test involves irrigating the external ear canal with warm and cool water for 40 seconds; you will experience a sensation of tilting or turning as your balance organs are stimulated by the water. You may also notice your eyes flicking in response to the stimulus (nystagmus). The velocity of these eye movements is recorded and compared for left and right ear stimulation. It is important to keep your eyes open and to remain alert during the test. The nurses who perform the test are highly skilled and will ensure that you feel safe and comfortable during the test. They may also engage you in conversation to ensure you stay awake.
PreparationYou will need see your general practitioner one week before the test to ensure there is no wax in your ears, and you must not eat or drink for 4 hours before the test. Diabetic patients could request an early morning (8.30 AM) appointment, take their regular hypoglycaemic tablets before the test and ensure they have breakfast when the test is completed. Patients on Insulin should delay the morning insulin dose until just before breakfast. If you are given a later appointment, you could eat an early (~5AM) breakfast and take your insulin/tablets before breakfast. Medications specifically taken to quell an attack of vertigo such as prochlorperazine ("stemetil") or Cinnarizine ("stugeron") should be withheld for 48 hours before the test. If you are a long term user of sedatives, please speak to your doctor to check if these can be withdrawn. All other medications including migraine prevention drugs, pain killers and cardiac medications should be taken with a sip of water, on-time as prescribed.
Time taken: 30-60 minutes