Billing code 31290: CSF leak repairMedicare rate & RVUs in Oregon
Reports endoscopic repair of a cerebrospinal fluid leak at the ethmoid region, such as a skull-base defect causing clear nasal drainage.
CMS doesn’t publish an office rate for 31290 in Oregon.
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 31290 covers
An otolaryngologist, often a rhinologist, uses a nasal endoscope to locate and close a cerebrospinal fluid leak involving the ethmoid region of the skull base. The repair may use graft material or a vascularized flap to seal the defect. Typical situations include persistent clear nasal drainage from a spontaneous, traumatic, or prior surgical skull-base opening. The procedure is generally performed in an operating room, commonly in a hospital outpatient or inpatient setting.
Report 31290 when the operative documentation identifies repair of a CSF leak in the ethmoid region; a sinus exploration or ethmoidectomy alone is not this service. The operative report should support the leak site and describe the endoscopic repair. CMS assigns a 10-day global period, which includes related postoperative visits during that period. When related nasal or sinus endoscopies are performed together, endoscopy-family pricing applies. For bilateral procedures, modifier 50 is paid at 150%. Assistant-at-surgery payment requires documentation of 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 31290 pays more and less in Oregon
| Payment locality | Office | Facility |
|---|---|---|
| Portland | Unavailable | $1,010.12 |
| Rest Of Oregon | Unavailable | $963.00 |
How the 31290 rate is calculated
Each of 31290’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 · 31290
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 18.14Practice expense 8.73Malpractice 2.84
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 31290
31290 has a 10-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 31290
CSF leak repair
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 010 | Minor procedure: the day of the procedure plus 10 days after are included. |
| Multiple procedures | 3 | Endoscopy family rules apply. |
| 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. |
| Split (54/55/56) | 0.10/0.80/0.10 | Share of the payment for pre-op, the procedure itself, and post-op care. |
Global surgery period · 31290
CSF leak repair
10-day global period ends
Oct 11, 2026
Covers Oct 1, 2026 through Oct 11, 2026 (11 days).
Visit on Oct 31, 2026
After the global period ends: visits and procedures are billed normally.
What modifiers do to the payment
Modifier 50 · payment effect
With and without the modifier
31290 without 50 · national facility
$992.34
CSF leak repair
31290-50 · Bilateral: 150%
$1,488.51
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).
31290 compared with similar codes
Compare codes
31290 vs 31291 vs 31254 vs 31255 vs 31288: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 31291CSF leak repair
- Both codes report endoscopic CSF leak repair, but the repair site determines the choice: ethmoid region for 31290 and sphenoid region for 31291.
- 31254Ethmoidectomy
- 31254 reports partial ethmoidectomy, not repair of a CSF leak. Use 31290 when the documented service is endoscopic closure of an ethmoid-region leak.
- 31255Ethmoidectomy
- 31255 reports total ethmoidectomy. It is not a substitute for 31290 when the procedure repairs an ethmoid-region CSF leak.
- 31288Sphenoid surgery
- 31288 involves sphenoidotomy with tissue removal. It does not describe repair of a CSF leak in the ethmoid region.
31290 billing questions
How is 31290 distinguished from 31291?
31290 is for endoscopic CSF leak repair in the ethmoid region. Use 31291 when the documented leak site is the sphenoid region.
Is an ethmoidectomy the same service as 31290?
No. An ethmoidectomy removes ethmoid sinus tissue, while 31290 reports endoscopic repair of a CSF leak at the ethmoid region. Select the code from the documented procedure.
How should bilateral repair be reported?
For a bilateral procedure, report modifier 50; CMS pays the bilateral procedure at 150%.
Are postoperative visits separately reported during the global period?
Related postoperative visits for 10 days are included in the 10-day global period.
Can an assistant or co-surgeon be reported?
Assistant-at-surgery payment requires documentation of medical necessity. Co-surgeons and team surgery are not permitted for this code under the CMS facts provided.
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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