We are preparing to operate on a new patient who had a C5-6 ACDF over three years ago by another surgeon. We are removing the plate, and doing a revision C5-6 ACDF w/ replacement of anterior hardware, peek and R ICBG. I am unsure what code to use for the revision fusion since one was already done at this level?? Do I simply use the regular 22551 and a 22830 for exploration of fusion or should the doctor document the extra work involved and append a modifier -22 to the 22551? Any advice or guidance would be much appreciated!