Crystal's MCW Coder Hub🧬 CPT Code 31267: Nasal/sinus endoscopy, surgical, with maxillary antrostomy; with removal of tissue from maxillary sinus
Short Definition
Nasal/sinus endoscopy, surgical, with maxillary antrostomy; with removal of tissue from maxillary sinus — an endoscopic surgical procedure in which a nasal endoscope is used to access the maxillary sinus, enlarge the natural maxillary sinus ostium (antrostomy), and remove tissue — including polyps, inflammatory mucosa, fungal debris, inspissated secretions, or other pathologic material — from within the maxillary sinus cavity. It is one of the most commonly performed FESS codes and is the preferred maxillary code when any tissue is removed from the sinus.
Full CPT Descriptor
Nasal/sinus endoscopy, surgical, with maxillary antrostomy; with removal of tissue from maxillary sinus
Long Clinical Definition
CPT 31267 describes a functional endoscopic sinus surgery (FESS) procedure targeting the maxillary sinus — the largest of the paranasal sinuses, located within the maxillary bone on each side of the nasal cavity beneath the orbit. The maxillary sinus drains naturally through its natural ostium into the middle meatus of the nasal cavity, under the middle turbinate, via the infundibulum. Chronic sinusitis, nasal polyps, anatomical obstruction, and mucosal inflammatory disease frequently obstruct this drainage pathway, resulting in retained secretions, recurrent infection, and mucosal thickening.
The surgical steps of 31267 are:
- Endoscope introduction — A 0° or 30° rigid nasal endoscope is inserted transnasally into the nasal cavity under general or local anesthesia with sedation.
- Middle meatus identification — The middle turbinate is identified and gently medialized to expose the middle meatus and the infundibulum.
- Uncinectomy — The uncinate process (a thin bone that partially covers the natural maxillary ostium) is partially or completely removed using a sickle knife, backbiter, or microdebrider. This step is essential for maxillary sinus access and is included in 31267.
- Maxillary antrostomy creation/enlargement — The natural maxillary sinus ostium is identified and enlarged posteriorly and inferiorly using through-cutting instruments, Kerrison rongeurs, or powered microdebrider to create a wide antrostomy allowing drainage and instrument access.
- Tissue removal from within the maxillary sinus — This is the distinguishing step of 31267 vs. 31256 — the surgeon passes instruments (curved suction, microdebrider, forceps, or irrigation) into the sinus cavity itself to remove pathologic tissue. This includes:
- Nasal polyps extending into the maxillary sinus.
- Inflammatory or hypertrophic mucosa.
- Fungal debris (in allergic fungal sinusitis or mycetoma).
- Purulent secretions or inspissated mucus (with curettage — not simple aspiration alone).
- Antrochoanal polyp with its origin in the sinus.
- Mucosal cysts (mucous retention cysts) when deliberately resected vs. marsupializated.
The tissue removal distinguishes 31267 from 31256. When only an antrostomy is created for drainage (ostium enlargement without deliberate tissue removal from within the sinus), report 31256. When the surgeon enters the sinus cavity and removes pathologic tissue, report 31267.
The Single Most Important Code Selection Decision — 31256 vs. 31267
| Feature | CPT 31256 | CPT 31267 |
|---|---|---|
| Endoscopic approach | Yes | Yes |
| Uncinectomy | Yes — included | Yes — included |
| Maxillary antrostomy | Yes | Yes |
| Tissue removal from within the sinus | No | Yes — required |
| Irrigation/lavage of sinus | May be performed | May be performed — not sufficient alone for 31267 |
| Polyp removal from maxillary sinus | Not included | Included |
| Fungal debris removal | Not included | Included |
| Curettage of sinus mucosa | Not included | Included |
| wRVU (approx 2026) | ~2.58 | ~3.15 |
| Global period | 090 | 090 |
Critical rule: Do NOT report 31256 and 31267 together for the same maxillary sinus. 31267 fully supersedes 31256 when tissue is removed — it includes everything in 31256 plus the tissue removal component. Reporting both is a NCCI violation.
31267 vs. 31295 — FESS vs. Balloon Sinuplasty
| Feature | CPT 31267 | CPT 31295 |
|---|---|---|
| Procedure type | Endoscopic tissue removal | Balloon ostial dilation only |
| Tissue removed | Yes — required for 31267 | No |
| Antrostomy created by | Cutting instruments / microdebrider | Balloon catheter dilation |
| Mucosal preservation | No — tissue is removed | Yes — mucosa is dilated, not resected |
| Combination in same session | May be reported together for different sinuses | May be reported with 31267 if both approaches used in separate sinuses |
| Can be reported for same maxillary sinus same session | No — use one or the other | No — mutually exclusive per same sinus |
Combination note: CPT guidelines state do not report 31256 or 31267 in conjunction with 31295 when performed on the same sinus. If the surgeon performs balloon dilation on the frontal sinus and traditional FESS with tissue removal on the maxillary sinus in the same operative session, both 31267 and 31296 (balloon frontal) may be reported separately.
CPT Code Family — FESS Building Block Model
FESS codes follow a building block (additive) model — each sinus opened and treated is separately reportable. Maxillary antrostomy work (31267) is NOT included in any combination ethmoid/frontal/sphenoid code — it must always be separately reported.
FESS CPT Code Family — Building Block Model
│
├── DIAGNOSTIC ENDOSCOPY (not separately reportable when surgical endoscopy performed)
│ └── 31231 — Nasal endoscopy, diagnostic, unilateral or bilateral (bundled into all surgical codes)
│
├── ETHMOID SINUS
│ ├── 31254 — Surgical endoscopy; with ethmoidectomy, partial (anterior only)
│ ├── 31255 — Surgical endoscopy; with ethmoidectomy, total (anterior and posterior)
│ └── (31254 is bundled into 31255 — report only 31255 for total ethmoidectomy)
│
├── MAXILLARY SINUS ← THIS NOTE
│ ├── 31256 — Surgical endoscopy; with maxillary antrostomy (no tissue removal)
│ └── 31267 — Surgical endoscopy; with maxillary antrostomy WITH tissue removal ← THIS NOTE
│ (31256 is bundled into 31267 — never report both for the same maxillary sinus)
│
├── FRONTAL SINUS
│ └── 31276 — Surgical endoscopy; with frontal sinus exploration, with or without removal of tissue
│
├── SPHENOID SINUS
│ ├── 31287 — Surgical endoscopy; with sphenoidotomy
│ └── 31288 — Surgical endoscopy; with sphenoidotomy, with removal of tissue from sphenoid sinus
│
├── COMBINATION ETHMOID + SPHENOID (include total ethmoidectomy by definition)
│ ├── 31257 — Total ethmoidectomy + sphenoidotomy (no tissue from sphenoid)
│ └── 31259 — Total ethmoidectomy + sphenoidotomy with tissue removal from sphenoid
│ (31267 for maxillary is always separately added to any of these combination codes)
│
├── BALLOON SINUPLASTY (separately reportable; not interchangeable with FESS for same sinus)
│ ├── 31295 — Balloon dilation of maxillary sinus ostium
│ ├── 31296 — Balloon dilation of frontal sinus ostium
│ ├── 31297 — Balloon dilation of sphenoid sinus ostium
│ └── 31298 — Balloon dilation of frontal and sphenoid sinus ostia
│
├── NASAL HEMORRHAGE CONTROL
│ └── 31238 — Surgical endoscopy; with control of nasal hemorrhage (SPA ligation or cautery)
│
├── OTHER SURGICAL ENDOSCOPY CODES (separately reportable with 31267)
│ ├── 31237 — Surgical endoscopy; with biopsy, polypectomy, or debridement
│ ├── 31240 — Surgical endoscopy; with concha bullosa resection
│ ├── 31241 — Surgical endoscopy; with ligation of sphenopalatine artery
│ └── 31239 — Surgical endoscopy; with dacryocystorhinostomy (DCR)
│
└── SEPTOPLASTY AND TURBINATE (commonly performed at same session, separately reportable)
├── 30520 — Septoplasty or submucous resection
└── 30140 — Submucous resection inferior turbinate
What Is Included in CPT 31267
All of the following are bundled into 31267 and must NOT be separately billed for the ipsilateral maxillary sinus:
- Nasal endoscopy (diagnostic component — 31231 is bundled into all surgical endoscopy codes).
- Uncinectomy — removal of the uncinate process to access the infundibulum and maxillary ostium.
- Infundibulotomy — opening the infundibulum.
- Maxillary antrostomy — creation or enlargement of the natural maxillary sinus ostium.
- Irrigation and lavage of the maxillary sinus with saline or antibiotic solution.
- Simple aspiration or suctioning of fluid, pus, or secretions from the maxillary sinus.
- Removal of all polyps, tissue, mucosa, fungal debris, or pathologic material from within the maxillary sinus cavity.
- Placement of absorbable packing material within the maxillary sinus (if used).
- Standard injection of vasoconstrictor (oxymetazoline, cocaine, or epinephrine) for hemostasis.
What Is NOT Included — Separately Reportable
| Service | CPT | Notes |
|---|---|---|
| Total ethmoidectomy (anterior and posterior) | 31255-51 | Separately reportable for ipsilateral or contralateral ethmoid work — never bundled into maxillary codes |
| Frontal sinus exploration with or without tissue removal | 31276-51 | Separately reportable for ipsilateral or contralateral frontal sinus work |
| Sphenoid sinusotomy with or without tissue removal | 31287 or 31288-51 | Separately reportable |
| Contralateral maxillary antrostomy with tissue removal | 31267-50 or 31267-LT/RT | Bilateral maxillary work billed with modifier -50 or separately with LT/RT |
| Concha bullosa resection | 31240-51 | Resection of pneumatized middle turbinate — separately reportable |
| Sphenopalatine artery ligation | 31241-51 | When performed for epistaxis control at same session |
| Septoplasty | 30520-51 | Separately reportable when performed at same session — very common combination |
| Submucous resection inferior turbinate | 30140-51 | Separately reportable — document as distinct procedure with separate indication |
| Nasal polypectomy (simple) | 30110 or 30115 | When simple polypectomy performed without maxillary sinus entry — but if polyps are within the sinus, their removal is included in 31267 |
| Balloon sinuplasty of frontal or sphenoid sinus | 31296/31297 | Reportable with 31267 if different sinuses treated by different approaches |
| E/M visit same day | 99212-99215 with -25 | Separately identifiable pre-operative E/M — requires modifier -25 |
| Navigation/image guidance | 61782 | When intraoperative computer-assisted navigation is used — separately reportable |
Image-Guided Surgery — CPT 61782
Intraoperative computer-assisted navigation (StealthStation, Brainlab, Fiagon, etc.) is increasingly used in complex revision FESS:
| CPT | Description | Notes |
|---|---|---|
| 61782 | Stereotactic computer-assisted volumetric (navigational) procedure, cranial, not intracranial | Used for FESS navigation — separately reportable with modifier -51 or -59 |
Documentation requirements for 61782 with FESS:
- Must document why navigation was medically necessary — revision surgery, distorted anatomy, proximity to orbit or skull base, prior surgery or trauma.
- Simple routine primary FESS does not support navigation billing.
- Navigation is most commonly billed with revision FESS, skull base cases, or cases with prior surgery altering landmarks.
Documentation Requirements
The operative note must support medical necessity and capture:
Pre-operative:
- Documented failure of maximal medical therapy — minimum 4-12 weeks of medical management (antibiotics, nasal corticosteroids, saline irrigation) without adequate response, per most payer policies.
- CT scan of the paranasal sinuses confirming maxillary sinus disease (mucosal thickening, opacification, polyps, air-fluid levels).
- Symptoms — facial pressure/pain, nasal congestion, purulent drainage, anosmia, decreased sense of smell, headache.
Operative documentation:
- Endoscopic approach confirmed — scope size and degree (0°, 30°, 45°).
- Anesthesia type — general, TIVA, or local with sedation.
- Uncinectomy performed (required component).
- Maxillary antrostomy creation — technique used (backbiter, Kerrison, microdebrider, punch), size of opening created.
- Tissue removal from within maxillary sinus — specifically describe what was removed (polyps, inflammatory mucosa, fungal debris, cyst) and the method of removal (microdebrider, forceps, curved suction with curettage). This is the critical documentation differentiating 31267 from 31256.
- Laterality — right, left, or bilateral.
- Other sinuses worked on — documented separately for each.
- Intraoperative findings — mucosal appearance, polyp burden, presence of fungi, osteitis.
Auditor red flag: An operative note that states only “antrostomy was performed and sinus was irrigated” without explicitly documenting tissue removal from within the sinus cavity does not support 31267 — it supports 31256 only. The tissue removal step must be explicit.
wRVU and Reimbursement
| Year | wRVU | Code |
|---|---|---|
| 2025 | ~3.22 | 31267 |
| 2026 | ~3.15 | 31267 (post 2.5% efficiency adjustment) |
| 2025 | ~2.64 | 31256 (comparison) |
| 2026 | ~2.58 | 31256 (comparison) |
The wRVU differential between 31267 (~3.15) and 31256 (~2.58) is approximately 0.57 wRVU per maxillary sinus — a meaningful difference when multiplied across high-volume sinus surgery practices. Accurate code selection between 31256 and 31267 based on documented tissue removal is both a compliance and a reimbursement imperative.
Global Period
- Global period: 090 (90-day global package)
- Includes:
- Pre-operative visit one day before surgery.
- All intraoperative services.
- All routine post-operative follow-up within 90 days.
- Nasal saline irrigation instruction and routine wound care.
- Standard nasal packing removal.
- Routine post-operative nasal endoscopic debridement within the global period — this is the single most important bundling point in FESS coding (see debridement section below).
- Outside the global (separately billable):
- Return to OR for complications — modifier -78 (post-op bleed requiring endoscopic cautery in OR, synechia requiring lysis in OR).
- Planned staged procedures — modifier -58 (planned staged bilateral FESS, planned staged revision).
- Unrelated conditions — modifier -24.
- Unrelated procedure by same surgeon — modifier -79.
Post-Operative Endoscopic Debridement — The Most Critical Bundling Issue in FESS
CPT 31237 (Nasal/sinus endoscopy, surgical; with biopsy, polypectomy, or debridement) is the code used for post-operative FESS debridement:
| Timing of Debridement | Billing Status |
|---|---|
| Routine in-office debridement during 90-day global period of 31267 | Bundled — NOT separately billable |
| Debridement performed as a return to OR procedure for a complication (adhesions, synechiae, significant obstruction) | Report 31237-78 — return to OR within global period |
| Debridement performed after the 90-day global period has expired | Report 31237 without any modifier — separately billable |
| Debridement performed in the office during global period for a NEW episode of sinusitis unrelated to the surgical procedure | Report 31237-24 — unrelated condition during global period; document new diagnosis |
This is one of the most commonly audited and most frequently overbilled areas in ENT — the routine post-operative nasal endoscopic debridement visits (often performed weekly for 4-8 weeks after FESS) are entirely bundled into the 90-day global period of 31267. They cannot be separately billed regardless of how much work they involve. This includes all nasal endoscopy, debridement, crust removal, synechia lysis performed in the office as routine post-FESS care.
Assistant at Surgery
- Generally not payable — Medicare MPFS designates FESS procedures including 31267 as procedures where an assistant at surgery is not separately payable.
- A surgical technologist or scrub tech assisting in the OR is part of the facility fee — not separately billable under the physician fee schedule.
- If a second physician assists (e.g., a resident or fellow), their services are part of the teaching physician rules and global surgical package.
- Some commercial payers may differ from Medicare on assistant payability — verify payer-specific policy.
HCC / Risk Adjustment
CPT 31267 does not carry HCC mapping. HCC weight flows from the ICD-10-CM diagnosis:
| ICD-10-CM | Description | HCC |
|---|---|---|
| J32.0 | Chronic maxillary sinusitis | No HCC |
| J33.0 | Polyp of nasal cavity | No HCC |
| J33.8 | Other polyp of sinus | No HCC |
| J32.4 | Chronic pansinusitis | No HCC |
| C31.0 | Malignant neoplasm of maxillary sinus | HCC 10 |
| D02.3 | Carcinoma in situ of other parts of respiratory system (maxillary) | No HCC |
The vast majority of diagnoses paired with 31267 are benign inflammatory conditions with no HCC weight. Malignant maxillary sinus neoplasms requiring FESS for biopsy or debulking would carry HCC 10 under Medicare Advantage risk adjustment — code precisely in those cases.
MS-DRG
CPT 31267 is almost universally performed as an outpatient/ASC procedure and does not generate an inpatient MS-DRG in routine practice. When performed inpatient due to significant comorbidities, it groups under MDC 03:
| DRG | Description | When |
|---|---|---|
| 135 | Sinus and Mastoid Procedures with MCC | Inpatient FESS with MCC |
| 136 | Sinus and Mastoid Procedures with CC | Inpatient FESS with CC |
| 137 | Sinus and Mastoid Procedures without CC/MCC | Inpatient FESS, no CC/MCC |
Inpatient FESS is rare and typically reserved for patients with:
- Severe comorbidities precluding outpatient discharge (decompensated heart failure, uncontrolled diabetes, morbid obesity with significant OSA requiring monitored care).
- Complicated sinusitis with orbital or intracranial extension requiring inpatient monitoring after surgery.
- Concurrent procedures requiring inpatient stay (e.g., endoscopic skull base surgery, CSF leak repair, orbital decompression).
Common ICD-10-CM Diagnoses Paired with CPT 31267
Chronic Sinusitis — Primary Indications
| ICD-10-CM | Description |
|---|---|
| J32.0 | Chronic maxillary sinusitis |
| J32.4 | Chronic pansinusitis (maxillary component drives 31267; other sinuses drive additional codes) |
| J32.8 | Other chronic sinusitis (involving more than one sinus but not pansinusitis) |
| J32.9 | Chronic sinusitis, unspecified |
| J01.00 | Acute maxillary sinusitis, unspecified (acute exacerbation requiring surgery — less common indication) |
| J01.01 | Acute recurrent maxillary sinusitis |
Nasal Polyps — Very Common Paired Diagnosis
| ICD-10-CM | Description |
|---|---|
| J33.0 | Polyp of nasal cavity (polyps originating in nasal cavity extending to maxillary sinus) |
| J33.8 | Other polyp of sinus (polyps specifically within a sinus cavity) |
| J33.9 | Nasal polyp, unspecified |
Specialized and Higher-Complexity Indications
| ICD-10-CM | Description | Notes |
|---|---|---|
| B44.81 | Allergic bronchopulmonary aspergillosis | Allergic fungal sinusitis (AFS) — high polyp burden, thick inspissated fungal debris |
| B44.1 | Other pulmonary aspergillosis | Aspergilloma/fungal ball within maxillary sinus |
| J33.8 + B44.81 | Fungal sinusitis with polyps | Code both underlying fungal etiology and polyp |
| J95.09 | Other postprocedural complications of respiratory system | Revision FESS for post-surgical adhesions or scarring |
| G47.33 | Obstructive sleep apnea | Concurrent nasal obstruction treated at same operative session |
| J30.9 | Allergic rhinitis, unspecified | Concurrent allergic disease driving polyp formation |
| J30.1 | Allergic rhinitis due to pollen | Seasonal allergic rhinitis with polyp disease |
| J34.3 | Hypertrophy of nasal turbinates | Concurrent indication for turbinate reduction (30140) |
| J34.2 | Deviated nasal septum | Concurrent indication for septoplasty (30520) |
| Q30.1 | Choanal atresia | Rare — endoscopic access may involve maxillary sinus |
| D14.0 | Benign neoplasm of middle ear, nasal cavity and accessory sinuses | Inverted papilloma — maxillary origin |
| [C31.0 | Malignant neoplasm of maxillary sinus | Malignancy — biopsy or debulking via FESS |
Modifier Quick Reference for CPT 31267
| Modifier | Use Case with 31267 |
|---|---|
| -50 | Bilateral maxillary antrostomy with tissue removal — both maxillary sinuses treated in same session; most payers accept -50; some require separate line items with -LT and -RT |
| -LT / -RT | Left or right laterality — use instead of -50 when payer requires separate line items for each side; required for all unilateral FESS claims |
| -51 | Multiple procedures same session — 31267 is the lower-value procedure when combined with a higher-RVU code such as 31255 (ethmoidectomy) or 30520 (septoplasty); apply to the lower-value code(s) |
| -22 | Significantly increased procedural services — revision FESS with dense adhesions, prior radiation, or severely distorted anatomy; document extended operative time and complexity in operative note |
| -25 | Separately identifiable E/M same day — pre-operative visit at which decision to operate was made, same day as procedure (minor procedure = -25, not -57); or separate clinical problem addressed same day |
| -57 | Decision for surgery — not typically applicable to 31267 as this is not a major procedure with a 090 global in the context of same-day decision-making; use -25 for E/M same day as minor procedure or for separate clinical problem |
| -58 | Staged procedure — planned contralateral FESS or planned second-stage sinus surgery within global period |
| -59 | Distinct procedural service — used when 31267 is reported with codes that may otherwise bundle (e.g., with 31240 concha bullosa, 31241 SPA ligation); confirms the procedures are distinct and separately indicated |
| -78 | Unplanned return to OR within global period — post-FESS hemorrhage, synechia requiring OR lysis, or recurrent obstruction requiring return to OR |
| -79 | Unrelated procedure during global period |
| -GY | Statutory exclusion — if payer determines procedure is not covered |
| -KX | Requirements met per medical policy — some MACs require -KX attestation for FESS medical necessity |
NCCI Bundling Summary
Per CMS NCCI policy:
- 31231 (diagnostic nasal endoscopy) is bundled into 31267 — never separately reportable when 31267 is performed.
- 31256 (maxillary antrostomy without tissue removal) is bundled into 31267 — never report both for the same maxillary sinus.
- 31295 (balloon sinuplasty, maxillary) must NOT be reported with 31256 or 31267 for the same maxillary sinus in the same session.
- Sinus lavage by cannulation (31000 for maxillary) is bundled into 31267 — lavage is an integral component when performed with a more definitive sinus procedure on the same sinus.
- Individual sinus FESS codes are NOT bundled into each other across different sinuses — 31267 (maxillary) and 31255 (ethmoid) are separately reportable, as they address anatomically distinct sinuses.
Coding Examples
Example 1 — Bilateral FESS, Chronic Pansinusitis with Nasal Polyps
Scenario 45-year-old with a 2-year history of chronic pansinusitis and bilateral nasal polyposis, failed maximal medical management (oral prednisone, fluticasone nasal spray, saline irrigation, prolonged antibiotics). CT sinus shows bilateral maxillary, ethmoid, frontal, and sphenoid opacification with nasal polyps. Undergoes bilateral FESS under general anesthesia: bilateral total ethmoidectomy, bilateral maxillary antrostomy with tissue removal (polyps removed from both maxillary sinuses), bilateral frontal sinus exploration with polyp removal, and bilateral sphenoidotomy with tissue removal.
CPT
- 31255-50 — Nasal/sinus endoscopy, surgical; with ethmoidectomy, total (anterior and posterior), bilateral.
- 31267-50-51 — Nasal/sinus endoscopy, surgical; with maxillary antrostomy with removal of tissue, bilateral; modifier -51 for multiple procedures.
- 31276-50-51 — Nasal/sinus endoscopy, surgical; with frontal sinus exploration with tissue removal, bilateral; modifier -51.
- 31288-50-51 — Nasal/sinus endoscopy, surgical; with sphenoidotomy with removal of tissue, bilateral; modifier -51.
ICD-10-CM
- J32.4 — Chronic pansinusitis (driving all four sinus codes bilaterally).
- J33.0 — Polyp of nasal cavity (nasal polyps — separately coded as a coexisting condition driving medical necessity).
Coding note: Each sinus is separately billed because FESS uses a building-block model. Modifier -50 is applied to all codes for the bilateral component. Modifier -51 is applied to the lower-value codes (31267, 31276, 31288) when combined with 31255 (typically the highest-RVU code in a pansinusitis FESS). Some payers require -LT/-RT instead of -50 — check payer preference.
Example 2 — FESS with Septoplasty and Turbinate Reduction
Scenario 38-year-old with chronic maxillary and ethmoid sinusitis, deviated nasal septum, and bilateral inferior turbinate hypertrophy. CT sinus shows bilateral maxillary opacification and bilateral ethmoid mucosal thickening. Nasal septum deviates to the left causing obstruction. Undergoes bilateral total ethmoidectomy, bilateral maxillary antrostomy with tissue removal, septoplasty, and bilateral submucous resection inferior turbinates.
CPT
- 31255-50 — Bilateral total ethmoidectomy.
- 31267-50-51 — Bilateral maxillary antrostomy with tissue removal; modifier -51.
- 30520-51 — Septoplasty; modifier -51.
- 30140-50-51 — Bilateral submucous resection inferior turbinate; modifier -51.
ICD-10-CM
- J32.0 — Chronic maxillary sinusitis.
- J32.2 — Chronic ethmoidal sinusitis.
- J34.2 — Deviated nasal septum (drives 30520).
- J34.3 — Hypertrophy of nasal turbinates (drives 30140).
Coding note: Septoplasty (30520) and turbinate reduction (30140) are separately reportable from FESS codes when performed for distinct, separately documented indications. The operative note must document the septoplasty and turbinate reduction as intentional, separately indicated surgical steps — not merely incidental to FESS access. All codes carry modifier -51 relative to the highest-RVU primary procedure.
Example 3 — Unilateral FESS, Right Maxillary Only, Isolated Chronic Maxillary Sinusitis
Scenario 52-year-old with right-sided chronic maxillary sinusitis only, failed 8 weeks of antibiotic therapy and nasal corticosteroids. CT sinus shows isolated right maxillary opacification with mucosal thickening; ethmoid, frontal, and sphenoid sinuses are clear bilaterally. Undergoes right nasal/sinus endoscopy with maxillary antrostomy and tissue removal (inflammatory mucosa and inspissated secretions removed from right maxillary sinus). No other sinuses worked.
CPT
- 31267-RT — Nasal/sinus endoscopy, surgical; with maxillary antrostomy with removal of tissue; right side only; modifier -RT for right laterality.
ICD-10-CM
- J32.0 — Chronic maxillary sinusitis.
Coding note: When only one maxillary sinus is treated, report 31267 with laterality modifier -RT (or -LT for left). Do NOT report 31267-50 (bilateral) or add any other sinus code. The payer will expect only one line item here with unilateral laterality.
Example 4 — Revision FESS with Navigation, Modifier -22
Scenario 61-year-old with recurrent chronic pansinusitis and nasal polyposis, status post prior bilateral FESS 5 years ago with multiple post-surgical adhesions and scarred middle turbinate remnants. CT sinus shows bilateral recurrent maxillary and ethmoid disease with significant post-surgical changes and bilateral middle turbinate lateralization. Revision bilateral FESS performed: bilateral total ethmoidectomy with lysis of adhesions, bilateral maxillary antrostomy with tissue removal. Image-guided navigation (Brainlab) used due to prior surgery and distorted anatomy near the orbit and skull base. Operative time 3.5 hours (documented vs. typical 1.5 hours for primary FESS).
CPT
- 31255-50-22 — Bilateral total ethmoidectomy; modifier -22 for significantly increased complexity (revision surgery, dense adhesions, extended operative time, distorted anatomy); attach cover letter and operative note.
- 31267-50-51-22 — Bilateral maxillary antrostomy with tissue removal; modifier -51 and -22.
- 61782-51-59 — Stereotactic computer-assisted navigational procedure (image-guided navigation); modifier -51 for multiple procedures; -59 for distinct procedural service.
ICD-10-CM
- J32.4 — Chronic pansinusitis.
- J33.0 — Polyp of nasal cavity.
- J95.09 — Other postprocedural complications of respiratory system (post-surgical scarring and adhesions — revision context).
Coding note: Modifier -22 on revision FESS is well-supported when the operative note explicitly documents prior surgery, the nature of adhesions encountered, extended operative time, and the proximity to critical structures driving use of navigation. A cover letter quantifying the increased time and complexity strengthens the -22 claim. Navigation (61782) is separately reportable but requires documentation that it was medically necessary — distorted anatomy and proximity to orbit/skull base in revision cases typically supports this.
Example 5 — Allergic Fungal Sinusitis, Bilateral Maxillary Debridement
Scenario 29-year-old with allergic fungal sinusitis (AFS) and massive bilateral nasal polyposis. CT sinus shows heterogeneous opacification of bilateral maxillary and ethmoid sinuses with hyperattenuating areas consistent with inspissated fungal material (Bipolaris species). Undergoes bilateral FESS: bilateral total ethmoidectomy, bilateral maxillary antrostomy with extensive tissue removal (thick allergic mucin, fungal debris, and inflammatory polyps removed from bilateral maxillary sinuses), bilateral sphenoid sinusotomy with tissue removal, bilateral frontal sinus exploration with polyp removal.
CPT
- 31255-50 — Bilateral total ethmoidectomy.
- 31267-50-51 — Bilateral maxillary antrostomy with tissue removal (allergic mucin + fungal debris + polyps); modifier -51.
- 31288-50-51 — Bilateral sphenoidotomy with tissue removal; modifier -51.
- 31276-50-51 — Bilateral frontal sinus exploration with tissue removal; modifier -51.
ICD-10-CM
- J33.8 — Other polyp of sinus (sinus polyps — AFS polyps within the sinuses).
- J33.0 — Polyp of nasal cavity (nasal polyps).
- B44.81 — Allergic bronchopulmonary aspergillosis (use appropriate fungal organism code — B44.81 for Aspergillus AFS; if Bipolaris/Curvularia, use B48.8 — other specified mycoses).
Coding note: Pathology specimens should be sent for both fungal culture and histopathology. The pathology report confirming fungal organisms provides additional medical necessity documentation. AFS with extensive allergic mucin requiring removal supports 31267 over 31256 unambiguously — document explicitly that fungal debris and allergic mucin were removed from within the sinus cavity.
Example 6 — Post-Op Routine Debridement vs. Return to OR Complication
Scenario A — Bundled (do NOT separately bill): Same patient from Example 1, day 10 post-FESS. Returns to office for routine post-operative nasal endoscopy with debridement and crust removal. Within the 90-day global period of all the FESS codes from the operative session.
CPT: Nothing — bundled into global period of 31267 (and all other FESS codes from operative session). Do NOT report 31237.
Scenario B — Separately Reportable (-78): Same patient, day 12 post-FESS. Develops significant post-operative hemorrhage from right sphenopalatine artery area not controllable in office. Returns to OR for endoscopic control of hemorrhage under general anesthesia.
CPT
- 31238-78-RT — Nasal/sinus endoscopy, surgical; with control of nasal hemorrhage (SPA cautery); modifier -78 for unplanned return to OR within global period; -RT for right laterality.
ICD-10-CM
- T81.810A — Hemorrhage complicating a procedure, initial encounter.
- J32.4 — Chronic pansinusitis (underlying condition — secondary diagnosis).
Scenario C — Separately Reportable (-24): Same patient, day 45 post-FESS. Presents to the surgeon with a new acute sinusitis episode unrelated to the surgical sites (left acute frontal sinusitis — the left frontal was not operated on). Surgeon performs office nasal endoscopy and documents active purulence in the left frontal recess.
CPT
- 99213-24 — Established patient E/M, low complexity; modifier -24 for evaluation of an unrelated condition during the 90-day global period.
ICD-10-CM
- J01.10 — Acute frontal sinusitis, unspecified (unrelated to the maxillary/ethmoid/sphenoid procedure — drives modifier -24 justification).
Key Coding Pearls
- 31267 supersedes 31256 for the same maxillary sinus — if tissue was removed from the maxillary sinus, report 31267; never report both codes for the same sinus; 31256 is appropriate only when antrostomy is created for drainage without tissue removal.
- Do not report 31231 with 31267 — diagnostic nasal endoscopy (31231) is always bundled into all surgical endoscopy codes; reporting it separately is a NCCI violation.
- Do not report 31000 (maxillary sinus lavage by cannulation) with 31267 — sinus lavage on the ipsilateral sinus is integral to 31267 and is bundled per NCCI.
- Maxillary is never included in combination codes — unlike the ethmoid/sphenoid combination codes (31257, 31259), there is no CPT combination code that includes the maxillary sinus; 31267 must always be separately reported when maxillary work is performed.
- Bilateral = modifier -50 or -LT/-RT — verify payer preference; CMS generally accepts -50; some commercial payers require separate line items with -LT and -RT; confirm billing rules before submitting.
- Post-op debridement is bundled for 90 days — this is the most commonly overbilled scenario in FESS; routine post-op nasal endoscopy and debridement visits are completely bundled into the global period; only return to OR (-78) or unrelated conditions (-24) escape the global.
- Modifier -22 for revision FESS — well-supported when prior surgery, dense adhesions, extended operative time, and critical structure proximity are documented; always attach the operative note to -22 claims.
- Navigation (61782) is separately reportable — must document medical necessity for navigation; routine primary FESS does not support 61782; reserve for revision, skull base, or distorted anatomy cases.
- Tissue removal documentation is the audit critical point — the single most common audit finding for 31267 is the absence of explicit tissue removal documentation; ensure the operative note describes what was removed, from where (inside the maxillary sinus cavity), and how.
- Code pansinusitis accurately — when all four sinuses are operated bilaterally, report each sinus code separately with -50; J32.4 (chronic pansinusitis) supports all four sinus codes simultaneously.
- Septoplasty and turbinate reduction are separately reportable — they address nasal structures distinct from the sinuses and have separate, independently documentable indications; never bundle 30520 or 30140 into 31267.
Suggested Obsidian Linkouts
- Otolaryngology CPT Codes Reference
- Global Surgical Package MOC
- Procedure Status & Complexity Modifiers
- -22 - Modifier 22, significantly increased procedural services
- -24 - Modifier 24, unrelated E/M during global period
- -25 - Modifier 25, separately identifiable E/M
- -50 - Modifier 50, bilateral procedure
- -51 - Modifier 51, multiple procedures
- -58 - Modifier 58, staged procedure
- -59 - Modifier 59, distinct procedural service
- -78 - Modifier 78, unplanned return to OR
- -LT - Modifier LT, left side
- -RT - Modifier RT, right side
- -KX - Modifier KX, requirements met per medical policy