Possible cyst

Question
My spayed female bun has started to get wee stains so I took her to the Vets. They found a lump which is very moveable and said it could be a cyst or a bladder stone. She is now on a course of antibiotics in case of cystitis or other infection and I'm to monitor the lump. It's difficult to tell 100% as she is bonded but I think she is drinking more water. We are back at the Vets next week. How do they find out if it's a cyst or a stone? Should it be removed whatever it is?
Her age is undetermined as she was a stray but maybe around hte 5 year old mark. She was spayed when guestimated at 18 months. Thank you.

Answer
Dear Jill,

I've never heard of a cyst that would move freely inside the bladder, but I guess anything is possible.  A radiograph might shed more light on the identity of the mass, though some uroliths/bladder stones are radio-translucent (not many, though).

If it's a stone, it probably should be removed if it does not resolve with medical treatment, as it can be painful.  Please see:

www.bio.miami.edu/hare/urinary.html

Hope this helps.

Dana