There are quite a few. Check out Appendix L in CPT. See if that helps.
Thank you. Yes I have been looking at Appendix L. I think I have it figured out. I could not figure out the process, but now I think I understand it as if ..you go through the aortic branch and go to a second order first, that is coded first. Then when you go to the third branch that is coded second with a modifier...even though the third branch is first in the coding book...Does that makes sense?
Within any vascular family that still allows separate catheterization codes you code to the highest selection first. It doesn't matter which one was catheterized first, just which is highest in that family. Then if a separate branch is catheterized, it is coded with the "each additional branch" code. If you go through one vessel to get to another - it isn't coded.