No office rate
Both codes describe endoscopic repair of a CSF leak, but 31290 applies to the ethmoid region; 31291 applies to the sphenoid region.
On this page
CMS RVU26D · Effective 2026-10-01
31291 CSF leak repair Medicare reimbursement rates in Maine
Reports endoscopic repair of a cerebrospinal fluid leak arising in the sphenoid region, typically performed transnasally by an otolaryngologist or skull-base surgeon. Compare 31291 office and facility rates across CMS payment localities in Maine.
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 31291 in Maine?
Maine 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
$1005.12–$1028.76
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.
Nasal and sinus surgery
About 31291: Endoscopic sphenoid CSF leak repair
Reports endoscopic repair of a cerebrospinal fluid leak arising in the sphenoid region, typically performed transnasally by an otolaryngologist or skull-base surgeon.
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.
CMS billing rules for 31291
- Global period
- Minor procedure with a 10-day global period: related postoperative visits for 10 days are included.
- Multiple procedures
- Endoscopy family pricing applies when related endoscopies are performed together.
- Bilateral procedures
- Bilateral procedure with modifier 50 is paid at 150%.
- Assistant at surgery
- Assistant at surgery is paid only with documentation of medical necessity.
- Co-surgeons
- Co-surgeons not permitted.
- Team surgery
- Team surgery not permitted.
Where the value comes from
- Work RVU19.07 · 59%
- Practice expense (office) RVU9.50 · 29%
- Malpractice RVU3.67 · 11%
112
Medicare services in 2024 · #4789 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.
31291 compared with similar codes
Office rates for Maine, from the same CMS release.
No office rate
This code describes sphenoid sinusotomy without tissue removal, not repair of a CSF leak.
No office rate
This code describes sphenoid sinusotomy with tissue removal. Choose 31291 when the service is repair of a sphenoid-region CSF leak.
Compare 31291 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
Rest Of Maine →
Office / nonfacility
Unavailable
Facility
$1005.12
Southern Maine →
Office / nonfacility
Unavailable
Facility
$1028.76
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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 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.
3,54331287,,Nasal/sinus endoscopy surg,A,,3.41,1.21,NA,1.21,,0.48,5.10,5.10,0,000,0.00,0.00,0.00,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,54431288,,Nasal/sinus endoscopy surg,A,,4.00,1.35,NA,1.35,,0.58,5.93,5.93,0,000,0.00,0.00,0.00,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,54531290,,Nasal/sinus endoscopy surg,A,,18.14,8.73,NA,8.73,,2.84,29.71,29.71,0,010,0.10,0.80,0.10,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,54631291,,Nasal/sinus endoscopy surg,A,,19.07,9.50,NA,9.50,,3.67,32.24,32.24,0,010,0.10,0.80,0.10,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,54731292,,Nsl/sins ndsc med/inf dcmprn,A,,15.50,7.80,NA,7.80,,2.28,25.58,25.58,0,010,0.10,0.80,0.10,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,54831293,,Nsl/sins ndsc med&inf dcmprn,A,,17.03,8.12,NA,8.12,,2.49,27.64,27.64,0,010,0.10,0.80,0.10,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,54931294,,Nsl/sins ndsc surg on dcmprn,A,,19.80,8.80,NA,8.80,,2.90,31.50,31.50,0,010,0.10,0.80,0.10,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00