Medicare rules regarding multiple procedures have been well-outlined and can be thought of as the standard. Most payers closely follow Medicare guidelines in this area. It is still necessary, though, to check with each individual payer for specific instructions. This is especially true regarding the use of the modifiers as discussed below.
Modifier -51 (Multiple Procedures) is commonly used to report procedures performed in addition to a primary procedure. Consider this modifier to be generally appropriate for the reporting of multiple procedures that are not bundled under National Correct Coding Initiative edits or that are not considered "add-on" codes. (These other circumstances will be discussed below. Also, this modifier is not used with "-51 exempt" codes, but these services are very rare in ophthalmic practice.)
It is good policy to list the highest value procedure first, and to list the remaining procedures in order from highest to lowest value. The -51 modifier is appended to all but the highest valued procedure. Typically, the claims processing program will reduce the payment for procedures reported with modifier -51 by 50% for the first service, with often a more profound reduction for subsequent services. Do not reduce your fee for the services reported with the -51 modifier, or else you may be paid 50% or less on your already reduced fee.
Use of modifier -59
Modifier -59 (Distinct Procedural Service) was created in response to Medicare's National Correct Coding Initiative. It is one of the most widely discussed modifiers, because of its ability to dramatically affect payment as well as its potential for inappropriate use. Indeed, use of this modifier will attract the attention of the payer and many payers will request to see chart notes before processing claims of this type.
This modifier can be thought of as the "bundle-breaking" modifier. Its use is appropriate in cases where services not typically reported together should be reported together because of "special circumstances."
The -59 modifier generally results in the same level of payment reduction as is seen with the -51 modifier, so it is again recommended not to report a reduced fee.
The means by which procedures are bundled under the Correct Coding Initiative or by private payers is beyond the scope of this article. Suffice it to say that the rationale behind creation of bundles may or may not be easy to understand.
CPT lists the circumstances in which the use of the -59 modifier may be considered appropriate. These would include a different session or patient encounter, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury or area of injury.
Because of the perceived misuse of modifier -59, Medicare has become somewhat more restrictive in their instructions regarding appropriate applications. Medicare prefers to see clear evidence of separate anatomic sites or separate patient encounters on the same date of service to legitimize use of this modifier.
The main mistake to avoid is to apply the -59 modifier simply because you do not believe a bundling edit between two codes should have been created. There are sanctioned ways to express your opinion, but application of the modifier -59 to break the bundle is not one of these. This mistake does create trouble with the authorities.
Review of CPT codes, including codes in the eye and ocular adnexa section, reveals certain services designated as "separate procedures." An example of such a code would be CPT 67715, Canthotomy (separate procedure). Separate procedure codes are only to be reported when carried out independently or distinct from other services provided at the same time. The use of -59 is appropriate when reporting these codes in this context of a distinct service.
With this example, it would generally be appropriate to report 67715-59 when performing a canthotomy in conjunction with CPT 68320, Conjunctivoplasty with conjunctival graft or extensive rearrangement. Canthotomy is distinct from a conjunctivoplasty and should be paid separately.