I've probably done over 100. I don't follow the pts unless they return for another one so I can't really say the percent of success. But when they do return, they are very grateful and it's probably the most rewarding procedure I do.
I think the key is to have psychiatry intimately involved. In my clinic, the referral can only come from a psychiatrist (a particular one). The pt must be actively enrolled in a PTSD program. The pt must have a f/u appointment with psych scheduled.
Docs who order procedures have no understanding of or interest in potential complications. They order the procedure like they order french fries. If there's a complication, it's 100% on us.
I know pain doc who did this a few years ago and the pt ended up committing suicide. The doc had no protocols in place and the pt was referred by a PCP after the pt heard about the shot. So after the death, everyone descended out the woodwork on the pain doc because he was the "treating doc" for PTSD. "What other treatments did you offer the pt?" "Did you provide therapy to the pt?" Etc, etc.
I still struggle with doing the procedure because the evidence is mixed. But OTOH, it's very difficult to stop doing something that some pts appear to get tremendous benefit from.