Kathryn - I hope you had success with the blocks.
When I was first diagnosed in 1991 with RSD in my face, they treated me very aggressively with stellate ganglion blocks and meds. I was in remission for 13 years. Now, I did have some minor flares during that 13 years, but nothing like before the blocks so I still consider that remission. Not sure what brought it out of remission. Then in 2009, I injured my right hand and it spread with a vengeance! In addition to my face, I now have it in both hands, left arm, both shoulders, left leg and both feet. They tried the blocks again this time, but it was really too late for them to work on me.
I am all for trying SGB's because they helped me so much at one time. Of course, everyone is different in how they respond.
All the best,