Wednesday, July 7, 2010
A rose by any other name ...
Had my first session as a research subject at the Department of Neurology at Royal Prince Alfred (RPA) Hospital yesterday. The researcher was Luke Chen who is a member of Professor Halmagyi's 'Balance Disorders Unit'.
He wants me to start using the term CANVAS instead of CABV for the disorder/syndrome/problem that I have. CABV only covered two of the inputs into my problem, whereas in reality, I have a triple whammy.
CABV = Cerebellar Ataxia | with | Bilateral Vestibulopathy
CANVAS = Cerebellar Ataxia | with | Neuropathy | with | Vestibular Arreflexia | Sydnrome
I don't like the term CANVAS because it is light-hearted. They like it because it is easy to remember.
So, what did the research involve?
I laid in a tunnel (like an MRI tunnel except home-made). My head was wedged and I was strapped down. Above my head was a plate with lights and a bar with lights. On the boney ridge behind each ear, they attached electrodes through which they pulsed an electrical current. On each eye, they placed a a contact lens with a hole in the centre of each and with wires attached to record movement. My eyeballs were anaethetised first.
Then they sent a pulse through the back of the ear and recorded how my eyes reacted. They started with 100% and reduced it down to zero, where I just stared at the light and they recorded my eye movements. The light moved in a pattern, around a circle in an apparently random way. Each time the shock hits the head, normal vision would be distorted. They expect my eyes to not be distorted. They will tell me more next time. This cycle took about 30 minutes. Then I had to follow the flashing lights up and down the bar, far-away to close-up. This took about 20 minutes.
I have another session where my sight will be video-taped.
What did they mean by triple-whammy? Balance is an interaction between sight, inner ear, and legs. It relies upon the sense of proprioception, of knowing where you are in space and where all your extremities are. Any impairment to one of these, confuses the body's sense of place. And puts one's balance out of kilter. i have an impairment in all three: legs, sight and inner-ear. I also have tinnitus which simply MUST be related, too. But what would i know, I am just the subject.
When I go in to have my eyes videotaped he will have an analysis of this test ready for me to try to understand.
This triple whammy (CANVAS) does not occur very frequently. Over the last decade, Halmagyi's team has worked with 40 cases which cover both Sydney AND Melbourne. Each case varied in which symptom started first. I do not have the classic Menieres "whirling head". Some start with that. I started with the neuropathy in '83-'84 sometime. The impact on my 'balance' only became apparent towards the end of 2008 when I started to trip, walk into walls, and wobble as I walked. The next step which followed early in 2009 was when I had difficulty working out what I was seeing as I drove. Is that car up the other end of the road heading in my direction or not? Little issues like that! At that time too, when I stopped the car and opened the door to get out, the road was still moving. Bit off-putting!
The walking-pole that I now use works wonders. I am effectively a tripod.
Luke said that this research was their only input until one of the group died - from other causes, he hastened to add. Anyways, the Prof got to be involved with the autopsy. And found that there was a crucial ganglion within the cerebellum that had shrivelled. They are still pondering on that one.