Billing code 61737: Laser ablationMedicare rate & RVUs in Washington
Reports intracranial laser interstitial thermal therapy involving multiple trajectories or multiple or complex lesions, performed to thermally ablate selected brain lesions.
CMS doesn’t publish an office rate for 61737 in Washington.
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 61737 covers
A neurosurgeon uses stereotactic planning to guide laser probes through one or more small cranial openings and heat targeted intracranial tissue. The technique may be used for selected brain tumors or epileptogenic lesions when thermal ablation is the planned treatment. This code represents the more involved LITT service, such as treatment requiring multiple trajectories or addressing multiple or complex lesions; it is not the single-trajectory, single-simple-lesion service.
Select the code from the operative plan and report: documentation should identify the lesion or lesions treated, their relevant complexity, the trajectories used, and the ablation performed. The stereotactic work integral to the LITT service is not separately reported as another portion of this procedure. CMS assigns a 0-day global period, so same-day preoperative and postoperative care is included. For a qualifying bilateral procedure, modifier 50 applies and Medicare pays at 150%. Assistant-at-surgery payment requires documented medical necessity; co-surgeons and team surgery are 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.
Where 61737 pays more and less in Washington
| Payment locality | Office | Facility |
|---|---|---|
| Rest Of Washington | Unavailable | $1,301.10 |
| Seattle (King Cnty) | Unavailable | $1,398.11 |
How the 61737 rate is calculated
Each of 61737’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 · 61737
RVUs × geographic indexes × conversion factor
Work22.10
22.10 RVUs× 1.000 GPCI
Practice expense8.99
8.99 RVUs× 1.000 GPCI
Malpractice9.33
9.33 RVUs× 1.000 GPCI
Adjusted RVUs
40.4200
Conversion factor
$33.4009
Medicare rate
$1,350.06
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 61737
The CMS indicators that decide how 61737 is paid alongside other services.
CMS payment indicators · 61737
Laser ablation
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 000 | Same-day global: pre- and post-op care on the day of the procedure is included. |
| Multiple procedures | 0 | No multiple-procedure reduction. |
| Bilateral (modifier 50) | 1 | Bilateral with modifier 50 pays 150% of the fee schedule amount. |
| Assistant at surgery (80/81/82/AS) | 0 | Not paid without supporting documentation. |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
What modifiers do to the payment
Modifier 50 · payment effect
With and without the modifier
61737 without 50 · national facility
$1,350.06
Laser ablation
61737-50 · Bilateral: 150%
$2,025.09
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).
61737 compared with similar codes
Compare codes · National
4 codes, side by side
How to choose
- 61736Laser ablation
- Use 61736 for one trajectory treating one simple lesion; use 61737 for multiple trajectories or multiple or complex lesions.
- 61796Cranial radiosurgery
- 61796 reports stereotactic radiosurgery for a simple cranial lesion. This code reports laser interstitial thermal ablation, not radiosurgery.
- 61798Cranial radiosurgery
- 61798 reports stereotactic radiosurgery for a complex cranial lesion. Choose this code when the performed treatment is LITT instead.
61737 billing questions
How does this code differ from 61736?
61736 is for LITT using one trajectory to treat one simple lesion. Report 61737 when the service involves multiple trajectories or multiple or complex lesions.
Can stereotactic guidance be billed separately?
The stereotactic work integral to the LITT service is included in this procedure. Do not separately report that same work as a distinct service.
What documentation supports choosing 61737?
The operative report should describe the treated lesion or lesions, the reason the treatment is multiple or complex, the trajectories used, and the laser ablation performed.
How is a bilateral procedure reported?
For a qualifying bilateral procedure, report modifier 50; CMS pays the bilateral service at 150%.
Can an assistant or co-surgeon be reported?
Assistant-at-surgery payment is allowed only when medical necessity is documented. Co-surgeons and team surgery are 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 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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