If you are coding a 2 or more level ACDF and are needing to use the cpt code 22851, is it OK to code it as 22851 and then again using the -59 modifier for each additional level? Or is this a CPT where we are only allowed to use this once per case? I have always coded it using the -59 modifier for each additional level. And actually have attended an AANS conference where they suggested this as well. But it was recently brought to my attn that I have been coding this incorrectly. Just would like to get some additional feedback. Thanks for your help. 
