I had spider veins on my ankles and lower legs and a few just above the knee. They would probably have been considered mild in severity.
I had them injected and the results have been good. Not every one that was done went away, but the great majority of them did or improved significantly. I did have brown spots for maybe three to six months in some places.
I wore the compression hose for 3 weeks after the procedure, as my friend, who's a nurse at the vein center, advised. She also told me that a lot of the success depends on the skill of the injector.