I'm going to guess why this is happening based upon what I've heard other ODs complain about with other major medical insurers. I'm going to assume that your office is an OD office. Is that correct?
If correct, this is what is probably happening. Mertain is basically saying that ODs can't provide medical eye care. Therefore, if you file a claim for medical eye care, probably whether you use the 99 or 92 codes, they deny it. If they have a vision plan, the insurer only wants to pay you at the vision plan rate instead of the, usually higher reimbursing, medical plan rate.
A couple of suggestions: 1) Try filing your medical eye care visits using the 992xx codes and see if they pay you. For some reason, some insurers feel that the 992xx codes are for medical eye care and the 920xx codes are for "routine/non medical" visits.
2) If using the 992xx codes doesn't help you get paid, then contact your state insurance commissioner and file a complaint with them that they are discriminating against your doctors and their legal ability to provide medical eye care under state law. You may also want to contact your state optometric association, again if your docs are ODs, to see if they have heard about this problem and have found a way to get it corrected.
Please let me know what you find out.
Tom Cheezum, OD, CPC, COPC