Ernie, the cold fluid is pumped into the ear on the affected side in order to induce nystagmus (involuntary eye movements associated with dizzyness brought on by the injection of cold water). If your vestibular system was mostly destroyed (by the AN or as a consequence of surgical removal of the AN), you should have very little nystagmus in response to the cold water in the ear. Your doctor is trying to determine from the test how much balance function you have remaining on your AN side. From what you said in your post, I'm guessing you had a translab surgical approach where the vestibular system was deliberately removed on the AN side during the procedure. Your doctor is trying to determine whether part of the vestibular system was unintentionally left behind, causing the wonkyheadedness (is that a word??
).
It is the
difference in remaining balance function on left and right sides/ears that causes dizziness and the wonky head syndrome. When you are immobile, the good side tells your brain you are not in motion. But the damaged side says you are. The conflicting signals creates a sense of disequilibrium.
Best,
Tumbleweed
