Surgical · Other

Reconstruction of orbital walls, rims, forehead, and nasoethmoid complex after intra- and extracranial excision of a benign cranial bone tumor, using multiple autografts (graft harvest included); total bone graft area under 40 square centimeters.

Verified May 8, 2026 · 5 sources ↓

Medicare: $1,849.07
Total RVUs: 55.36
Global, days: 90
Region: Other

Drawn from CMSEmednyFindacodeBillrazor

Documentation requirements

What must appear in the operative or office note to support the claim.

Source · Editorial brief grounded in 5 cited references ↓

Pathology or imaging confirmation of a benign cranial bone tumor (e.g., fibrous dysplasia) as the indication for excision
Operative note specifying both the intra- and extracranial extent of tumor excision and the reconstruction performed
Explicit documentation of all anatomic structures reconstructed: orbital walls, orbital rims, forehead, nasoethmoid complex — as applicable
Total surface area of bone grafting in square centimeters, documented intraoperatively to support selection of 21182 vs. 21183 or 21184
Documentation that multiple autografts were used and identification of donor site(s) — graft harvest is bundled but the harvest sites must be described
Preoperative imaging (CT preferred) demonstrating tumor extent and bony involvement to justify the scope of reconstruction

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 51 Multiple procedures 52 Reduced services 58 Staged or related 62 Co-surgeons 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon AS PA/NP/CNS assistant

What this code covers

Source · Editorial summary grounded in 5 cited references ↓

CPT 21182 covers reconstruction of the orbital walls, orbital rims, forehead, and nasoethmoid complex performed after intra- and extracranial excision of a benign tumor of the cranial bone — fibrous dysplasia is the canonical example. The procedure requires multiple autografts, and graft harvest is bundled into the code; do not separately bill a graft-harvest code. This version of the family applies when the total area of bone grafting is less than 40 sq cm. Larger defects are reported with 21183 (40–80 sq cm) or 21184 (greater than 80 sq cm).

This is a 090-day global procedure. All routine post-op management through day 90 is included. An unrelated procedure during the global period requires modifier 79. A staged or planned related procedure requires modifier 58. An unplanned return to the OR for a complication related to the original surgery requires modifier 78. The code sits in the reconstruction-of-head section alongside 21179, 21180, 21181, and the larger-graft counterparts 21183 and 21184.

Because the procedure is inherently craniofacial and rarely bilateral in the anatomic sense, modifier 50 is almost never applicable here. The high RVU value reflects the complexity of multi-site autograft harvest combined with orbital and nasoethmoid reconstruction. Site of service matters: HOPD and ASC payment rates differ substantially — see the site-of-service comparison table on this page.

RVU & reimbursement

Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	31.77
Practice expense RVU	17.69
Malpractice RVU	5.9
Total RVU	55.36
Medicare national rate	$1,849.07
Global period	90 days

Payment by site of service

Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.

Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026

Setting	Medicare rate (national)
Office (PFS non-facility) Procedure performed in physician's office	$1,849.07
HOPD (APC 5165) Hospital outpatient department	$6,048.05
ASC (PI J8) Ambulatory surgical center (freestanding)	$3,833.49

Common denial reasons

The recurring reasons claims for CPT 21182 get rejected.

Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓

Wrong code selected from the 21182–21184 family because graft area in square centimeters was not documented intraoperatively
Separate billing of autograft harvest (e.g., 20900, 20902) — harvest is bundled into 21182 and triggers an NCCI bundling edit
Missing or inadequate documentation of benign tumor diagnosis; payers require pathology or imaging confirmation before approving craniofacial reconstruction
Post-op services billed without modifier 24 or 79 during the 90-day global period, resulting in automatic denial
Operative note describes only extracranial excision when the code requires both intra- and extracranial excision — mismatch between code and note

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 5 cited references ↓

01What distinguishes 21182 from 21183 and 21184?

Graft area only. All three codes describe the same reconstruction after benign cranial tumor excision with multiple autografts. Use 21182 when total bone graft area is under 40 sq cm, 21183 for 40–80 sq cm, and 21184 for over 80 sq cm. Measure and document intraoperatively.

02Is autograft harvest billed separately with 21182?

No. The code descriptor explicitly includes obtaining the grafts. Billing a separate harvest code (20900, 20902, or similar) will trigger an NCCI bundling edit and deny.

03Can modifier 22 be used if the reconstruction was unusually complex?

Yes, but it requires documentation of what made the case substantially more work than typical — extensive scarring from prior surgery, revision after failed reconstruction, or unusually large or complex bony defects. A brief addendum in the operative note quantifying the additional time and effort supports the modifier 22 request.

04What modifier applies if the surgeon returns to the OR within the 90-day global for a complication?

Modifier 78 for an unplanned return related to the original procedure. Modifier 79 for an unrelated procedure during the global period. Do not use 58 for unplanned returns — 58 is for staged or planned procedures.

05Does 21182 require a specific ICD-10 diagnosis code pairing?

The procedure is built around benign tumor excision — fibrous dysplasia (M85.0x) is the classic pairing. Payers will scrutinize claims with malignant or traumatic diagnosis codes; the code descriptor limits it to benign cranial bone tumors. Confirm your ICD-10 selection reflects the benign pathology before submitting.

06Is 21182 appropriate for traumatic craniofacial reconstruction?

No. This code is specifically for reconstruction following excision of a benign cranial bone tumor. Post-traumatic craniofacial reconstruction maps to different CPT codes in the orbital and craniofacial repair sections. Using 21182 for trauma will result in a diagnosis-procedure mismatch denial.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira's AI scribe captures the tumor type and extent (intra- vs. extracranial), all reconstructed structures by anatomic name, the number and donor sites of autografts, and the measured total bone graft area in square centimeters. That last detail directly determines whether 21182, 21183, or 21184 is correct — missing it is the leading reason this code family gets downcoded or denied on audit.

See how Mira captures CPT 21182 documentation