Hi Mick,
My cyst is located on the left side of my brain, i honestly can't tell you if my cyst is small or large, but being that my balance issue was the cause of my cyst being discovered and it got to a size that it was effecting my motor skills i would imagine it was large. My memory of my balance issue's are vague as it was 20 odd years ago, but i do remember it started with falling over at school and being sent home and from then on it quickly got worse, within a few days i was unable to stand on my own and was very sick. After many visit's back and forth to the Dr's i was diagnosed with an arachnoid cyst and within 1 month had my shunt inserted. After the operation i was in a wheel chair for a couple of months and from that point on, i've had no other balance related symptoms. Not sure if this helps much,but it's all i can remember concerning my balance issues. Hopefully you will see some improvement in the near future, my best wish's to you, Brad