On this page
- What Is Modifier 50?
- When Should You Use Modifier 50 or RT and LT?
- What Does the Bilateral Indicator Mean?
- How Are Bilateral Eye Procedures Paid?
- Which Eye Codes Use Modifier 50?
- How Do You Bill a Bilateral Intravitreal Injection?
- Which Bilateral Billing Errors Cause Denials?
- How Is Bilateral Billing Different in an ASC or Hospital?
Key takeaways
- Medicare Part B bills bilateral surgery on one line with modifier 50, 1 unit and a doubled charge.
- Medicare pays 150% of the fee schedule amount when the code's bilateral indicator is 1.
- Tests that are bilateral by definition, such as OCT and fundus photos, take neither modifier 50 nor RT and LT.
- Some Medicaid and commercial plans do not accept modifier 50 for eye procedures and want RT and LT lines.
What Is Modifier 50?
Modifier 50 is a CPT modifier for a bilateral procedure, the same procedure performed on both sides of the body in the same session. In eye care it means the same procedure on both eyes on the same date.
RT and LT are HCPCS modifiers that report a single side. They can report a procedure on one eye, or both eyes on 2 separate lines. Both approaches report the same work, so the choice depends on the code and the payer. All 3 are among the laterality codes in ophthalmology modifiers.
When Should You Use Modifier 50 or RT and LT?
Use modifier 50 for Medicare Part B bilateral surgery on codes with a bilateral indicator of 1, and use RT and LT lines when the payer does not accept modifier 50. The table compares the 2 ways to bill the same bilateral procedure.
| Factor | Modifier 50 | RT and LT lines |
|---|---|---|
| Claim lines | 1 | 2 |
| Units | 1 | 1 on each line |
| Charge | Doubled, for both eyes | The single charge on each line |
| Usual payer | Medicare Part B | Many Medicaid and some commercial plans |
| Different diagnosis for each eye | Harder to show | Each line points to its own diagnosis |
Medicare Part B has required one line with modifier 50 and 1 unit for bilateral surgery since 2013. New York Medicaid, by contrast, does not accept modifier 50 for eye procedures and wants RT and LT.
What Does the Bilateral Indicator Mean?
The bilateral indicator is a value from 0 to 3, or 9, in the Medicare Physician Fee Schedule that says whether a code can be billed as bilateral and how it is paid. Check it for every code before billing both eyes.
| Indicator | Meaning | How to bill both eyes |
|---|---|---|
| 0 | The bilateral adjustment does not apply | Follow the payer, and expect payment for one side only |
| 1 | The bilateral adjustment applies, paid at 150% | Modifier 50 on one line for Medicare |
| 2 | The code is already bilateral | Bill once, with no 50 and no RT or LT |
| 3 | Each side is paid at 100%, common for some tests | Modifier 50 or RT and LT, by contractor rule |
| 9 | The bilateral concept does not apply | No bilateral modifier |
Indicators can change in the yearly fee schedule update, so check the current file instead of relying on memory.
How Are Bilateral Eye Procedures Paid?
Medicare pays a bilateral procedure with indicator 1 at 150% of the single-side fee schedule amount, or the actual charge if that is lower. That is why the charge on the modifier 50 line should be doubled.
If the line shows a single charge, Medicare pays the lower of the charge or 150% of the fee, so a single charge caps payment at 100%. A doubled charge lets the full 150% pay. Payers that use RT and LT lines often apply their own reduction to the second line, so the total can still be close to 150%.
Which Eye Codes Use Modifier 50?
Bilateral intravitreal injections and some eyelid surgeries are the eye procedures most often billed with modifier 50, while bilateral tests are billed once with no modifier. The table lists common eye codes and how both eyes are billed to Medicare.
| Code | Service | Both eyes, Medicare Part B |
|---|---|---|
| 67028 | Intravitreal injection | 67028-50, 1 unit, doubled charge |
| 15823 | Upper eyelid blepharoplasty | 15823-50 for both upper lids |
| 67904 | Ptosis repair | 67904-50 for both upper lids |
| 92133, 92134 | OCT | Bill once, no modifier |
| 92250 | Fundus photography | Bill once, no modifier |
| 68761 | Punctal plug | One line per eyelid with E1 to E4 |
Confirm each code's current indicator in the fee schedule before setting a billing rule. When only one eye is tested on a bilateral-by-definition code, some payers want modifier 52 for the reduced service.
How Do You Bill a Bilateral Intravitreal Injection?
For Medicare Part B, bill 67028-50 on one line with 1 unit and a doubled charge, and bill the drug on the lines the contractor asks for. The example shows aflibercept 2 mg in both eyes for wet macular degeneration.
| Claim line | Units | Diagnosis |
|---|---|---|
| 67028-50 | 1 | H35.3231, wet AMD, both eyes, active |
| J0178-JZ-RT | 2 | H35.3231 |
| J0178-JZ-LT | 2 | H35.3231 |
Some contractors want the drug on one line with all 4 units, so check the local billing article. A commercial payer that does not accept modifier 50 is billed 67028-RT and 67028-LT instead. Our retina billing services team keeps these rules for each payer.
What if each eye has a different diagnosis?
Use the laterality code for each eye. On a modifier 50 line, point to both diagnoses. On RT and LT lines, point each line to its own eye's code, which is one reason some payers prefer separate lines.
Which Bilateral Billing Errors Cause Denials?
Bilateral eye claims deny most often because the wrong format is sent to a payer, the units are wrong or a bilateral-by-definition test carries a modifier. These are the 5 errors to check.
- Modifier 50 with 2 units. Medicare wants 1 unit on a modifier 50 line.
- 50 with RT or LT. One line cannot say both eyes and one eye.
- Single charge. A modifier 50 line with a one-eye charge caps payment.
- Modifier on OCT. 92133, 92134 and 92250 take no laterality modifier.
- Wrong payer format. Modifier 50 sent to a plan that wants RT and LT.
Our ophthalmology medical coding services load each payer's bilateral rule into the billing system so every claim goes out in the right format.
How Is Bilateral Billing Different in an ASC or Hospital?
The facility claim for an ASC or hospital outpatient department follows its own bilateral rules, separate from the surgeon's claim. The surgeon and the facility can bill the same bilateral procedure in different formats.
Check the facility payment rules for each payer before the first bilateral case. Our ophthalmic ASC billing team handles facility claims for eye surgery centers.