Video Head Impulse Test (vHIT) — ICS Impulse

Explained in simple words

1vHIT stands for video Head Impulse Test. It is one of the most modern tests available for giddiness.

2Our clinic uses the ICS Impulse system made by Otometrics, Denmark. It was among the first three such installations in the whole of India.

3Inside each ear there are three small tubes, called semicircular canals, placed at different angles. Together, the two ears have six canals.

4Each canal senses head movement in one particular direction — like nodding, shaking the head, or tilting it to the shoulder.

5Older tests could only tell whether the ear as a whole was weak. This test can check each of the six canals separately.

6That is a big advantage, because sometimes only one canal is damaged while the rest are perfectly normal.

7For the test you wear a very light pair of goggles with a small high-speed camera. A red laser dot is used to help you fix your gaze on a spot on the wall.

8The camera is fixed to the goggles and records your eye at a very high speed — far faster than the human eye can see.

9The doctor stands behind you and holds your head. You are asked to keep looking at the dot on the wall and to relax your neck.

10Then the doctor turns your head by a very small amount, quickly and gently, to one side and back. This is repeated in different directions.

11The movements are small and brief. There is no jerking, no pain and no injury to the neck when done by a trained doctor.

12In a healthy person, when the head turns, the eyes stay locked on the target automatically. This reflex is very fast and very accurate.

13If a canal is not working, the eyes are dragged along with the head and then have to jump back to find the target. The camera catches that tiny corrective jump.

14The computer then draws a graph for each of the six canals and gives a number showing how well each one is functioning.

15From this, the doctor knows exactly which canal in which ear is affected, and how severely.

16The test is quick, usually finished in about fifteen to twenty minutes, and it does not usually make you feel giddy.

17There is no water, no air, no electricity, no injection and no radiation involved.

18Because it is so quick and comfortable, it can even be done in elderly patients and in people who are still feeling unwell.

19It is also very useful in an emergency, to tell whether sudden severe giddiness is coming from the ear (which is usually not dangerous) or from the brain, such as a stroke (which needs urgent care).

20The results are stored in the computer, so when you come again after treatment, we can compare and show you exactly how much you have improved.

21Please tell the doctor beforehand if you have any neck problem, recent neck injury, or severe spine disease, so that the test can be modified or avoided.

22Contact lenses can usually be kept on, but heavy eye make-up should be avoided as it can blur the camera image.

23After the test the doctor explains the graphs to you in simple words and plans your treatment or exercises accordingly.