That makes sense that it probably is your catheter hitting a nerve, since you weren't having the spasms before it was revised. I, too, had trouble with the distal end moving (and wrapping around my diaphragm), so much so, that they decided to shorten it, so now it only comes down to the bottom of my sternum so it can't reach any organs. It has solved the problem. I hope the problem goes away for you. It sounds like you and your neurosurgeon are on the same wavelength which is really helpful, and unfortunately rare! Keep us posted on any developments, it's from people sharing their trials that's directly helped me.