CPT code 31291: CSF leak repair, sphenoid region2026 Medicare rate & RVUs in Texas
Reports endoscopic repair of a cerebrospinal fluid leak arising in the sphenoid region, typically performed transnasally by an otolaryngologist or skull-base surgeon.
CMS doesn’t publish an office rate for 31291 in Texas.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
Your location
On this page 9 sections
What 31291 covers
This service repairs a cerebrospinal fluid leak in the sphenoid region through a nasal endoscope. An otolaryngologist, rhinologist, or skull-base surgeon typically identifies the leak and closes the defect, often with graft material or a tissue flap. The operation is generally performed in a hospital or ambulatory surgery setting; the operative note should establish the sphenoid site and describe the endoscopic repair rather than sinus surgery for routine inflammatory disease.
Select this code based on the location of the leak, not simply because the surgeon worked in the sphenoid sinus. The record should document the leak site, endoscopic approach, and repair performed. Related endoscopies performed during the same session are subject to endoscopy-family pricing. CMS assigns a 10-day global period, including related postoperative visits during that period. For bilateral reporting, 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 31291 pays more and less in Texas
The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.
8 of 8 payment localities
| Payment locality | Office | Facility |
|---|---|---|
| Austin, TX | Unavailable | $1,082.55 |
| Beaumont, TX | Unavailable | $1,039.58 |
| Brazoria, TX | Unavailable | $1,052.12 |
| Dallas, TX | Unavailable | $1,063.90 |
| Fort Worth, TX | Unavailable | $1,062.32 |
| Galveston, TX | Unavailable | $1,058.64 |
| Houston, TX | Unavailable | $1,125.81 |
| Rest of Texas | Unavailable | $1,048.77 |
How the 31291 rate is calculated
Each of 31291’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 · 31291
RVUs × geographic indexes × conversion factor
Work19.07
19.07 RVUs× 1.000 GPCI
Practice expense9.50
9.50 RVUs× 1.000 GPCI
Malpractice3.67
3.67 RVUs× 1.000 GPCI
Adjusted RVUs
32.2400
Conversion factor
$33.4009
Medicare rate
$1,076.85
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 31291
31291 has a 10-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 31291
CSF leak repair, sphenoid region
| 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 · 31291
CSF leak repair, sphenoid region
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
31291 without 50 · national facility
$1,076.85
CSF leak repair, sphenoid region
31291-50 · Bilateral: 150%
$1,615.28
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).
31291 compared with similar codes
Compare codes · National
4 codes, side by side
How to choose
- 31290CSF leak repairEthmoid region
- Both codes describe endoscopic repair of a CSF leak, but 31290 applies to the ethmoid region; 31291 applies to the sphenoid region.
- 31287SphenoidotomyWithout tissue removal
- This code describes sphenoid sinusotomy without tissue removal, not repair of a CSF leak.
- 31288Sphenoid surgerySphenoid tissue removal
- This code describes sphenoid sinusotomy with tissue removal. Choose 31291 when the service is repair of a sphenoid-region CSF leak.
31291 billing questions
How is this distinguished from 31290?
Use 31291 when the cerebrospinal fluid leak being repaired is in the sphenoid region. Code 31290 is for a leak in the ethmoid region.
Does this code cover ordinary sphenoid sinus surgery?
No. It represents endoscopic repair of a cerebrospinal fluid leak in the sphenoid region, not routine sphenoidotomy or removal of sinus tissue.
Can another nasal or sinus endoscopy be reported in the same session?
Related endoscopies performed together are subject to CMS endoscopy-family pricing. The operative record should identify each distinct service and its site.
What documentation supports reporting this code?
Document the sphenoid location of the leak, the endoscopic approach, and the repair performed. The site helps distinguish this code from ethmoid-region leak repair.
How are bilateral procedures and assistant services handled?
CMS pays bilateral reporting with modifier 50 at 150%. Assistant-at-surgery payment requires documented medical necessity; co-surgeons and team surgery are not permitted.
What postoperative care is included?
The 10-day global period includes related postoperative visits during those 10 days.
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
Fee sheets
Put 31291 and the rest of your codes on one sheet
Your codes at your locality, with payer contracts beside Medicare.
Build my fee sheet