“…As far as possible we tried to distinguish between the initial pain relief (i.e., the percentage of patients that achieve pain reduction immediately after one intervention) and long-term pain relief (i.e., the percent-age of patients that achieve prolonged pain reduction, which involves variable follow-up between studies from 1 to 6 months) after a series of sympatholytic interventions or after sympathectomy. 109 In RSD and causalgia, about 85% of the patients report a positive acute effect of SE, SB, and IVRS, but fewer patients experience long-term relief (60% in SB and 30% in IVRS). In posttraumatic neuralgias the sympatholytic interventions are clearly less effective.…”