I have had surgery three times, three stents in the last year an a half. They went up an shattered the stones with a laser. There shouldn't be any spasms, I never had any. The stent is there to keep the tube open an let urine, stone fragments an blood pass. The ureter might twinge or spasm, that is when you will feel pain or discomfort. that is also when a fragment is moving. Once you have the surgery, the only time it hurts is when you start to pee an the pain will subside quite quickly as you continue to pee. The stent will be removed in 24-48 hours. I would take surgery in a heart beat an suggest it, as its the quickest way an least painful way of dealing with these little buggers. You will know an be able to tell when the fragments are travelling down the ureter and or coming out. Good Luck. Surprised that the 9mm stone didn't do a full blockage an go septic the minute it dropped into the ureter. That would show on an ultrasound xray right away. After the surgery drink lots of water to help flush out the stone fragments. Sit to pee for the first few times after the surgery an take a real deep breath just before you do pee. Holding onto the side the stone is on, just above the hip. Just like placing your hands on your hips does help a little.