That is what is used normally in the blocks. I had three and none of them made any difference . I thought they were mainly to diagnose if it was a sympathetic nerve issue or as in type 2 CRPS a different path. I am probably confused but that seems to be what I have read and what my blocks were, that I do know as my cousin ...a O.R. nurse was with me for them. Sooooo delighted to hear of your relief. I hope it continues forever.