Billing code 66175: Canal dilationMedicare rate & RVUs in Utah
Reports glaucoma surgery that dilates the aqueous outflow canal and leaves a stent or other device in place to support drainage.
CMS doesn’t publish an office rate for 66175 in Utah.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 9 sections
What 66175 covers
An ophthalmic surgeon treats impaired aqueous drainage by passing an instrument through the outflow canal, dilating it, and leaving a stent or other device in place. The procedure is used for glaucoma when improving flow through the eye’s natural drainage pathway is the surgical goal. It is generally performed in an operating room, often with gonioscopic visualization, and may be done during the same session as cataract surgery.
Report 66175 when canal dilation includes retention of a device or stent; documentation should identify the treated eye, the dilation procedure, and the retained device. Dilation without a retained device is reported with 66174. CMS assigns a 90-day global period, including the day-before preoperative visit and 90 days of related postoperative care. When multiple procedures are performed in one session, the highest-valued is paid in full and others at 50%. Bilateral reporting with modifier 50 is paid at 150%. An assistant at surgery may be paid; co-surgeons require supporting documentation, and team surgery is not permitted.
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.
66175 in Utah
| Payment locality | Office | Facility |
|---|---|---|
| Utah | Unavailable | $600.29 |
How the 66175 rate is calculated
Each of 66175’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 66175
RVUs × geographic indexes × conversion factor
Work9.11
9.11 RVUs× 1.000 GPCI
Practice expense8.74
8.74 RVUs× 1.000 GPCI
Malpractice0.72
0.72 RVUs× 1.000 GPCI
Adjusted RVUs
18.5700
Conversion factor
$33.4009
Medicare rate
$620.25
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 66175
66175 has a 90-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 66175
Canal dilation
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 090 | Major surgery: the day before, the day of, and 90 days after are included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 1 | Bilateral with modifier 50 pays 150% of the fee schedule amount. |
| Assistant at surgery (80/81/82/AS) | 2 | Paid. |
| Co-surgeons (62) | 1 | Permitted with supporting documentation. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
| Split (54/55/56) | 0.10/0.70/0.20 | Share of the payment for pre-op, the procedure itself, and post-op care. |
Global surgery period · 66175
Canal dilation
90-day global period ends
Dec 30, 2026
Covers Sep 30, 2026 through Dec 30, 2026 (92 days, including the day before surgery).
Visit on Oct 31, 2026
Day 30 of the 90-day post-op period: related follow-up care is included in the surgical payment.
Pre-op dayGlobal period
What modifiers do to the payment
Modifier 50 · payment effect
With and without the modifier
66175 without 50 · national facility
$620.25
Canal dilation
66175-50 · Bilateral: 150%
$930.38
Both sides on one line with modifier 50 are paid at 150% of the fee schedule amount (subject to multiple-procedure rules with other procedures).
66175 compared with similar codes
Compare codes · National
5 codes, side by side
How to choose
- 66174Canaloplasty
- Both codes describe transluminal dilation of the aqueous outflow canal. Choose 66175 when a device or stent remains in place; choose 66174 when none is retained.
- 66183Drainage device
- 66183 describes insertion of an anterior drainage device. 66175 is for dilation of the aqueous outflow canal with a device or stent retained there.
- 66179Glaucoma shunt
- 66179 describes aqueous shunt surgery without a graft. Choose it for shunt placement rather than canal dilation with a retained stent.
- 66180Glaucoma shunt
- 66180 describes aqueous shunt surgery with a graft. It is a different drainage procedure from dilation of the outflow canal under 66175.
66175 billing questions
How do I choose between 66175 and 66174?
Use 66175 when a stent or other device is left in place after canal dilation. Use 66174 for canal dilation without a retained device.
Is the retained stent separately reported?
The retained device is part of the service represented by 66175. Do not report a separate code just for leaving that device in place.
Can 66175 be reported with cataract surgery?
It may be performed during the same session as cataract extraction. Document each procedure performed and apply the applicable same-session coding rules.
What supports reporting 66175?
The operative report should identify the treated eye, canal dilation, and the device or stent left in place. Those details distinguish this service from dilation without retained hardware.
How is bilateral 66175 reported under the CMS facts?
Use modifier 50 for a bilateral procedure; CMS pays it at 150%.
Does the 90-day global include related follow-up?
Yes. The global period includes the day-before preoperative visit and 90 days of related postoperative care.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
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