As doydie said, some have good experiences and some have bad. I had bad, both times. First time was old fashioned way, hunt and peck so to speak, and my recent one was the flouro thingy. I have had 2 LP's, 20yrs apart. So, to answer if it can change, mine did over the years with the first being negative and the second to being positive. My first neuro I had out here was skeptical if I truely had MS and after the LP he panicked and said he cant take care of an MS patient properly and sent me to a MS specialist. I will be eternally greatful to that neuro as he sent me to a great specialist. Best advice on all this, stay calm, dont panic. Hard to do I know, but its the best thing to do for you right now. Take it in stride and cross the bridges as you get to them. Like Debbie said, so many diseases mimic MS, and its a process of elimination. Breathe, and know your among friends here who really do know what your going thru.