Payer-specific rules — especially rules that vary for every claim — not only make collecting revenue difficult, but also add to the cost of collection of monies earned by the physicians.

A blog clarifies Novitas’ instructions for reporting modifier 50 when bilateral procedures are performed. The instructions from Novitas state that bilateral services should be reported with one line with modifier 50 and one unit of service. The blog also refers to CGS’ instructions to not use modifier 50 if a bilateral procedure is performed during a return to the operating room (78 modifier). In this case, CGS specifically instructs that they require the bilateral service to be reported on two separate lines, one with modifier LT and the other with modifier RT.

Investigate Modifier 50 Guidelines

I searched to see if Novitas or other Medicare carriers had similar instructions on handling the reporting of bilateral services when they require a return to the operating room, with no success. A biller who works in Kentucky (CGS jurisdiction) indicated to me that they continually encounter problems with CGS in terms of how they want all bilateral services reported. It turns out that CGS often wants modifiers LT and RT with two lines on the claim for services that did not involve a return to the operating room.

Look to NCCI for Answers

I went to the definitive authority for modifiers used with Medicare Part B claims, the NCCI Policy Manual for Medicare Services, effective January 1, 2019. The instructions for reporting bilateral procedures are found on pages 40 and 41 of Chapter 1 – General correct coding policies- final 121218.

Under section V, Medical Unlikely Edits (MUEs), (3), the policy guidelines address CMS policies that limit units of service (UOS). Item ii states the following:

ii             If the bilateral surgery indicator is “1”, a bilateral surgical procedure must be reported with a “1” UOS and modifier 50 (bilateral modifier). A bilateral diagnostic procedure may be reported with “2” UOS on one claim line, “1” UOS and modifier 50 on one claim line, or “1” UOS with modifier RT on one claim line plus “1” UOS and modifier LT on a second claim line.

These instructions are confusing and need to be taken apart to understand what billers are being instructed.

The first sentence gives the instruction to bill bilateral procedures that have a bilateral indicator of “1” on a single line with modifier 50 and one UOS. That is easy and clear.

The next sentence delineates DIAGNOSTIC bilateral procedures from all other bilateral procedures (therapeutic). If the bilateral procedure is diagnostic, the instructions are that the service may be billed in any one of three ways:

1. One line with modifier 50 with 2 UOS
2. One line with modifier 50 with 1 UOS (just like bilateral therapeutic services)
3. Two lines, with modifier LT on one line and 1 UOS and modifier RT on the second claim line and 1 UOS

Since NCCI guidelines provides flexibility in how bilateral diagnostic services can be reported, Medicare Administrative Contractors (MACs) can take advantage of the flexibility and select one, two, or all three methodologies when allowing the reporting of bilateral diagnostic services. However, the NCCI guidelines do not give that same flexibility to the MACs for therapeutic bilateral services, which can only be reported on one line with modifier 50 and 1 UOS, per the NCCI guidelines.

It appears that not all the MACs are following the NCCI guidelines, based on anecdotal information provided by billers. And non-adherence to a single set of rules is making it more difficult to bill and collect the proper reimbursement for services rendered.

The Medicare Part B Internet Only Manual, Medicare Claims Processing Manual Pub. 100-04, chapter 12, Physicians/Nonphysician Practitioners, page 109, section 40.7, states:

B … If a procedure is not identified by its terminology as a bilateral procedure (or unilateral or bilateral), physicians must report the procedure with modifier “-50.” They report such procedures as a single line item.

Guidelines for Diagnostic Bilateral Procedures are Open to Interpretation

The rules CGS has put in writing for bilateral surgeries performed during a return to the operating room is neither supported in the NCCI guidelines nor the Medicare Part B Internet Only Manual (IOM). Additionally, there is no support in CPT® for such a policy.

The Medicare Part B IOM has very clear and straightforward instructions. MACs should be following these instructions, and all Medicare Part B physician claims for bilateral services should be billed on one line with modifier 50 and 1 UOS.

The above are the rules for Part B Medicare. Unless a non-Part B Medicare payer follows NCCI, you cannot use the guidelines from the NCCI to support trying to hold the payer to this policy. If the payer states that they follow NCCI, you can use the contents of these guidelines to assist in getting a single policy at least for therapeutic bilateral services. Unfortunately, bilateral diagnostic services still might have one, two, or up to three different methodologies of reporting the services.