Hi Cola,
I've already had surgery once (a little over 12 years ago-easy to remember as my son was born a month before they found my tumor). It was rather large, 3.5 cm, and had my brain stem squished (that's the medical term) against the side of my skull. I've had a certain amount of balance issues, but I guess I got used to those. Recently though they've gotten worse, vertigo at the top of and on stairs-very scary, falling over when I'm standing next to the table helping with homework (explaining that one to my GP when I tore the ligament in my thumb when I did it was very embarrassing.) Have had the balance testing done and surprise surprise they recommended more vestibular therapy. I'm searching around for a good therapist now. In the meantime I make sure I have a good hold on the handrail and my other hand or shoulder on the wall. I hope you find an answer to your imbalance increase. Let us know how you're doing.