I highly suggest that you have this test. I was unsure before mine, but it ended up being the best thing I did in terms of receiving undeniable proof. Before the bone scan, I had a few doctors who knew about my RSD by talking with me and looking at the surface symptoms but there were still many more that needed a solid medical document. For me this test was valuable because of the letter I received, stating that the bone damage clearly caused by RSD appeared very advanced, and that amount would only be possible after years of the disease. In my words it basically proved to me that I really was speaking the truth all those years. Even when they tried to tell me it was nothing. I had been misdiagnosed and shoved aside for 5 years, and this was the test that proved everything. The results placed me on disability and continue to be helpful when it comes to seeing specialists. I have also recently been moved ahead of a long waiting list. So basically I think that since you have been referred, it can't hurt to go through with the scan. No matter how long you have had the RSD, they should be able to pick up something that will convince someone else. You never know what the results may be and the radioactive dye is the very smallest amount possible. You won't even know it's there.