No office rate
Both describe internal canal-based glaucoma surgery. Choose 66174 when no device or stent is retained and 66175 when one remains.
On this page
CMS RVU26D · Effective 2026-10-01
66174 Canaloplasty Medicare reimbursement rates in Michigan
Reports internal dilation of the eye’s aqueous drainage canal for glaucoma when the surgeon leaves no stent or other device in place. Compare 66174 office and facility rates across CMS payment localities in Michigan.
Amounts below use the non-QP conversion factor for participating physicians. These are base physician payments before claim-level adjustments, not patient costs or total hospital charges.
What does Medicare pay for 66174 in Michigan?
Michigan has 2 payment localities in this comparison. Use the service location to choose the applicable amount. These are the supported base rates for the 2 payment areas shown below, using the same CMS release.
Office / nonfacility
No supported rate
Facility setting
$519.18–$544.17
2 of 2 localities have a supported rate.
These are locality ranges, not averages or address-specific quotes. A facility-setting amount covers the physician service; it does not include a hospital’s separate bill. Choose a locality below to inspect its calculation, compare other payment areas, or price a percentage of Medicare.
Glaucoma surgery
About 66174: Ab interno canaloplasty without implant
Reports internal dilation of the eye’s aqueous drainage canal for glaucoma when the surgeon leaves no stent or other device in place.
An ophthalmologist reaches the drainage angle from inside the eye and enlarges Schlemm canal to improve aqueous outflow, leaving no implant or stent behind. The procedure is used to lower intraocular pressure in glaucoma and is typically performed in an operating room with gonioscopic visualization by an ophthalmologist, often one with glaucoma surgical expertise.
Report 66174 when the canal is dilated without a retained device; use 66175 when a device or stent remains. The operative report should identify the treated eye, the canal-dilation work, and whether an implant was left in place. CMS assigns a 90-day global period, including the day-before preoperative visit and 90 days of related postoperative care. In a same-session multiple-procedure claim, the highest-valued procedure is paid in full and other procedures at 50%. Modifier 50 bilateral payment is 150%. An assistant at surgery may be paid; co-surgeons require supporting documentation, and team surgery is not permitted.
CMS billing rules for 66174
- Global period
- Major surgery with a 90-day global period: the day-before preoperative visit and 90 days of related postoperative care are included.
- Multiple procedures
- Standard multiple procedure reduction: the highest-valued procedure is paid in full and others at 50% when performed in the same session.
- Bilateral procedures
- Bilateral procedure with modifier 50 is paid at 150%.
- Assistant at surgery
- Assistant at surgery may be paid.
- Co-surgeons
- Co-surgeons paid only with supporting documentation.
- Team surgery
- Team surgery not permitted.
Where the value comes from
- Work RVU7.43 · 46%
- Practice expense (office) RVU8.17 · 50%
- Malpractice RVU0.58 · 4%
37.3K
Medicare services in 2024 · #895 by national volume
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
66174 compared with similar codes
Office rates for Michigan, from the same CMS release.
No office rate
66179 describes aqueous shunt surgery without a graft; 66174 dilates the eye’s drainage canal without leaving a device or stent.
No office rate
66183 is for insertion of an anterior-segment drainage device. 66174 is canal dilation without a retained device or stent.
No office rate
66170 represents filtering surgery, while 66174 uses an internal canal-based approach to improve aqueous outflow.
Compare 66174 by payment locality
Find the payment area for your service address, then open its rate page for calculation inputs, release history and the percentage-of-Medicare tool. A city may cross payment-area boundaries; the ZIP lookup above helps resolve the location.
2 of 2 payment localities
Detroit →
Office / nonfacility
Unavailable
Facility
$544.17
Rest Of Michigan →
Office / nonfacility
Unavailable
Facility
$519.18
Need rates for a whole code list?
Fee-sheet and API access are in early access. Tell us which codes and locations your team needs.
66174 billing questions
How does 66174 differ from 66175?
Use 66174 when the canal is dilated and no device or stent is left in the eye. Use 66175 when a device or stent remains.
Can 66174 be reported with cataract surgery?
It may be performed in the same session as cataract extraction when both services are carried out and documented. CMS applies its same-session multiple-procedure payment reduction.
What documentation supports 66174?
The operative report should describe the internal approach, the canal-dilation work, the eye treated, and whether any device or stent was retained.
How is bilateral 66174 reported?
CMS lists this as a bilateral procedure paid at 150% with modifier 50. The documentation should support treatment of both eyes.
What postoperative care is included?
The 90-day global period includes the day-before preoperative visit and 90 days of related postoperative care.
May an assistant or co-surgeon be paid?
An assistant at surgery may be paid. Co-surgeons are paid only with supporting documentation; team surgery is not permitted.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense, and malpractice RVUs, adjusted by each locality’s geographic indices and the applicable conversion factor. Unavailable or separately priced services are labeled rather than assigned a made-up amount.
Source: RVU26D. Effective 2026-10-01 through the day before 2027-01-01.
7,36566160,,Glaucoma surgery,A,,12.08,12.34,NA,12.34,,0.98,25.40,25.40,0,090,0.10,0.70,0.20,2,1,1,1,0,9,,33.4009,09,0,99,0.00,0.00,0.00
7,36666170,,Glaucoma surgery,A,,13.59,13.41,NA,13.41,,1.09,28.09,28.09,0,090,0.10,0.70,0.20,2,1,2,1,0,9,,33.4009,09,0,99,0.00,0.00,0.00
7,36766172,,Incision of eye,A,,14.47,15.18,NA,15.18,,1.16,30.81,30.81,0,090,0.10,0.70,0.20,2,1,2,1,0,9,,33.4009,09,0,99,0.00,0.00,0.00
7,36866174,,Trluml dil aq o/f can w/o st,A,,7.43,8.17,NA,8.17,,0.58,16.18,16.18,0,090,0.10,0.70,0.20,2,1,2,1,0,9,,33.4009,09,0,99,0.00,0.00,0.00
7,36966175,,Trluml dil aq o/f can w/st,A,,9.11,8.74,NA,8.74,,0.72,18.57,18.57,0,090,0.10,0.70,0.20,2,1,2,1,0,9,,33.4009,09,0,99,0.00,0.00,0.00
7,37066179,,Aqueous shunt eye w/o graft,A,,13.65,12.91,NA,12.91,,1.09,27.65,27.65,0,090,0.10,0.70,0.20,2,1,2,0,0,9,,33.4009,09,0,99,0.00,0.00,0.00
7,37166180,,Aqueous shunt eye w/graft,A,,14.63,13.26,NA,13.26,,1.17,29.06,29.06,0,090,0.10,0.70,0.20,2,1,2,0,0,9,,33.4009,09,0,99,0.00,0.00,0.00