Insight · Eye care · Glaucoma surgery
MIGS pays, but only one procedure per eye per session.
Seven Medicare contractor MIGS LCDs are in force. Noridian's and WPS's share the same core rules: one device per eye, mild to moderate open-angle glaucoma on drops when done with cataract, refractory glaucoma when done alone, and no stacking. 66991 is the one eye ASC code CMS expects to grow in 2027. Here is how to bill it cleanly.
By ASP-RCM Editorial, Healthcare RCM Practice · Updated
The question for your glaucoma surgeons
When a surgeon adds a goniotomy to a stent at cataract surgery, who tells the patient that Medicare may deny the whole claim?
Stent per eye
With cataract surgery or alone, under the Noridian and WPS MIGS LCDs
66991 ASC payments, 2027
CMS estimate in the CY2027 ASC final rule, while 66984 falls 2%
Required since June 1, 2026
Noridian billing article A57863 revision 10 for MIGS codes
Proposed iDose LCDs
Noridian, WPS, CGS, Palmetto, NGS. Comments closed July 4, 2026, not final
MIGS LCDs by MAC
Final LCDs titled Micro-Invasive Glaucoma Surgery in the Medicare Coverage Database on November 6, 2026. Always read your own MAC's current version.
| MAC | LCD | Current version effective |
|---|---|---|
| Noridian (JE, JF) | L38299 | October 23, 2025 |
| WPS (J5, J8) | L39907 | August 27, 2026 |
| CGS | L37578 | April 2, 2026 |
| Listed as Wellpoint Federal | L37244 | April 1, 2026 |
| Palmetto GBA | L37531 | November 17, 2024 |
| Novitas | L38223 | December 30, 2019 |
| First Coast | L38233 | December 30, 2019 |
What the Noridian and WPS LCDs cover
Both LCDs carry the same criteria. Older LCDs at other MACs may differ, so check yours.
Non-covered
- Cataract surgery plus two MIGS procedures in the same eye, such as a stent plus goniotomy or canaloplasty
- A MIGS procedure and an aqueous shunt in the same eye at the same session
- Multiple stents beyond those in the device
- Ocular hypertension, or MIGS as first-line treatment for mild to moderate glaucoma
Covered
- One trabecular stent per eye with cataract surgery, for mild or moderate open-angle glaucoma
- The patient is currently on an ocular hypotensive medication
- Standalone: refractory glaucoma after a failed filtering or cilioablative procedure
- Standalone: medicated IOP of 20 mmHg or more, or progression, on maximally tolerated therapy
The codes, units and 2027 surgeon fees
Unit rules from Noridian billing article A57863. Fees are national, unadjusted CY2027 PFS amounts, an illustration, not a contracted rate.
| Code | What it is | Billing rule | 2027 surgeon fee |
|---|---|---|---|
| 66991 | Cataract with IOL and anterior segment drainage device | 1 unit per eye per day, however many devices | $556.64 |
| 66989 | Complex cataract with drainage device | 1 unit per eye per day | $687.16 |
| 0671T | Trabecular meshwork drainage device, no cataract | 1 unit per eye per date of service | Contractor priced |
| 0449T | Aqueous drainage device, subconjunctival, first device | 1 unit per eye per date of service | Contractor priced |
| 66174, 66175 | Canaloplasty without and with retained stent | One MIGS procedure per session | $514.88, $592.54 |
| 65820 | Goniotomy | Bundled with 66174, never billed together | $687.48 |
Fees: CY2027 PFS final rule Addendum B total facility RVUs x $32.6286. Category III codes carry status C, so the MAC prices them.
A clean MIGS claim, step by step
Check the diagnosis
Primary open-angle glaucoma, mild or moderate stage, by eye, for 66989 and 66991 per the article's ICD-10 list.
Document the drops
Current ocular hypotensive medication in the note. Standalone cases need the refractory history.
Pick one procedure
Cataract plus one MIGS, or one MIGS alone. Anything more risks denial of the entire claim.
Code and side
One unit, RT or LT, or 50 when both eyes are done. Goniopuncture goes to 66999 with a narrative.
Device and drug items to watch in 2027
iDose TR pass-through ends
J7355 pass-through runs through June 30, 2027 in the facility setting. 0660T stays in APC 5492 at status J1.
iDose LCDs still proposed
Five MACs proposed LCDs for anterior segment drug-eluting systems. The comment period ended July 4, 2026. None are final yet.
0671T stays device-intensive
CMS kept 0671T device-intensive in the ASC for 2027, which protects the device portion of the facility rate.
0730T is not device-intensive
CMS refused device-intensive status for laser trabeculotomy with OCT guidance, because its patient interface is not inserted or implanted.
Score your last 10 MIGS cases
Tick what holds for every case.
MIGS is the one eye surgery line CMS expects to grow in the ASC in 2027. Keep it paid by billing one procedure per eye, one unit, with laterality, and a chart that shows the glaucoma stage and current drops.
Questions operators ask next
Can you bill two MIGS procedures with cataract surgery?
Under the Noridian and WPS MIGS LCDs, cataract surgery may be combined with a single MIGS procedure. Adding a second, such as a stent plus goniotomy or canaloplasty in the same eye at the same session, is non-covered. The Noridian billing article warns this risks denial of the entire claim.
How many units of 66991 can be billed?
Noridian article A57863 allows one unit of 66991 or 66989 per eye, per day, regardless of how many devices are inserted. Since June 1, 2026 it also requires modifier RT, LT or 50 to show which eye. 0449T and 0671T are also limited to one unit per eye per date of service.
Does Medicare cover MIGS for ocular hypertension?
Not under the Noridian or WPS MIGS LCDs. Covered use with cataract surgery requires mild or moderate open-angle glaucoma treated with a hypotensive drop. Standalone use requires refractory glaucoma. The LCDs say other indications are not currently considered reasonable and necessary.
Can goniotomy 65820 be billed with canaloplasty 66174?
No. Noridian's MIGS billing article states 65820 is bundled with 66174 and the two cannot be reported together. Goniopuncture has no specific code and is reported with unlisted code 66999 with a narrative description of the procedure. Other MACs' articles may word this differently, so check yours.
Want your MIGS claims checked against your MAC's LCD?
Send us 90 days of cataract and glaucoma surgery claims and remits. A senior ophthalmology billing partner tests each case against the LCD, units and laterality rules, in a free 30-minute call with a written gap report after.
Keep reading
Sources
- CMS Medicare Coverage Database, Noridian LCD L38299 Micro-Invasive Glaucoma Surgery
- CMS Medicare Coverage Database, Noridian article A57863 Billing and Coding: MIGS
- CMS Medicare Coverage Database, WPS LCD L39907 Micro-Invasive Glaucoma Surgery
- CMS Coverage API, final and proposed LCD reports
- Federal Register public inspection, CY2027 OPPS/ASC final rule CMS-1850-FC
- CMS, CY2027 PFS final rule CMS-1848-F, Addendum B
Checked November 6, 2026. LCD criteria differ by MAC and change; the details above are from Noridian and WPS documents current on November 6, 2026. Commercial and Medicare Advantage plans set their own rules. General information, not legal advice.