Reviewing this; it states "frozen sectioning" from your post and reviewing our CPT book I would only bill 88314 for the hitsochemical stain on frozen tissue block. I'm unfamiliar with the Zamboni fixative but from what I googled it seems to be a frozen additive. I do not have a pathology report to review but from my experience coding muscle biopsies when we receive mGT, OildRedO, PAS, for specimens that were frozen, with embedding media in isopentane cooled by liquid nitrogren that is how I would have coded this. Again, I am reviewing all my notes and I know that Congo Red would typically be billed with 88313; however if it is applied to a frozen tissue block I would have selected 88314. I would not bill both charges unless the pathology report states otherwise and I do not have that report.
Have a great evening,
Dana Chock, CPC, CANPC, CHONC, CPMA, CPB, RHIT
Coding Specialist 3 - pathology