CPT 15842Surgery

Nerve palsy microsurg graft

CPT code 15842 covers microsurgical nerve grafting procedures to repair facial nerve damage that causes paralysis, typically following trauma, tumor removal, or other nerve injuries. This complex surgery involves using specialized microscopes to harvest and transplant nerve tissue to restore facial movement.

Showing rates for

National Average

Base Medicare rate

$2,628.80

This calculator gives a typical-case estimate using standard Medicare modifier rules. Actual payment depends on payer policies, documentation, code-specific CMS status indicators, and locality. Verify before billing.

RVU breakdown

Work RVU

41.01

PE RVU (NF)

32.75

MP RVU

7.51

Total RVU

81.27

Conversion factor: 32.3465 · Source: CMS MPFS RVU25A · Confidence: High

NCCI bundling edits

Loading bundling edits…

Billing tips

Document exact operative time, microscope magnification levels used, number of nerve grafts harvested, donor nerve site(s), and length of each graft in millimeters. CPT 15842 requires microsurgical technique confirmation.
Impact: Prevents $2,628.80 denial and supports modifier 22 claims for additional $525-$788 when complexity documented
Separately bill for nerve harvest site closure and donor site management only if significant additional work beyond typical graft harvest is performed and documented. Most harvest work is included in 15842.
Impact: Avoid unbundling denials while capturing legitimate additional work when donor site requires complex closure or grafting (potential $200-$400 additional)
When performed with tumor resection or parotidectomy, clearly document that nerve grafting was unplanned/not routine and required due to intraoperative findings of nerve sacrifice or injury necessitating immediate reconstruction.
Impact: Supports medical necessity and prevents $2,628.80 denial for 'routine' or 'expected' component of primary procedure
Submit detailed operative report within 48 hours of claim submission highlighting microsurgical anastomosis technique, number of sutures per coaptation, and nerve stimulation/monitoring results confirming graft placement.
Impact: Reduces payer requests for additional documentation and accelerates payment by 15-30 days on average for this high-value claim
For commercial payers, verify prior authorization requirements as many require pre-approval for microsurgical nerve procedures. Medicare does not require prior auth but some MAOs do.
Impact: Prevents 100% claim denial ($2,628.80 loss) and patient balance billing issues; pre-auth typically takes 3-5 business days

Live Field Datano reports yet

Real billers contribute denial patterns and appeal strategies for this code. Once 5+ reports come in, you’ll see live aggregated data here — the only place this exists, free.

Working with CPT 15842?

Get the free Revenue Protection Toolkit — the denial triggers, modifier pitfalls, and bundling conflicts that quietly cost you reimbursement. Instant download.

Help build the field knowledge

MedPayIQ gets smarter as billers contribute. If you've had this code denied, share what happened so others learn from it. Anonymous, no patient info.

Related actions

Applicable modifiers

Mod 22

When to use: Use when the procedure requires substantially greater complexity, time, or technical difficulty than typical cases, such as revision surgery with extensive scarring, multiple nerve grafts required, or complex anatomy. Document additional 30+ minutes operative time and specific complexities.

Reimbursement impact: Typically increases reimbursement by 20-30% ($525-$788 additional) with proper documentation comparing to standard procedure difficulty and time

Mod 50

When to use: Apply when bilateral facial nerve grafting is performed during the same operative session. Each side must be documented separately with clear medical necessity for bilateral repair.

Reimbursement impact: Increases reimbursement to 150% of base rate ($3,943.20 total) when both facial nerves require grafting

Mod 51

When to use: Use when 15842 is performed with other distinct procedures during the same session (e.g., concurrent parotidectomy or tumor resection). List 15842 as secondary if another procedure has higher RVU value.

Reimbursement impact: Reduces reimbursement by 50% for the secondary procedure, resulting in $1,314.40 for 15842 when billed as add-on

Mod 59

When to use: Append when nerve grafting is performed on a distinct anatomic site or separate nerve branch during the same session as another procedure, to indicate it's not a component of the primary procedure.

Reimbursement impact: Prevents bundling denials and maintains full reimbursement ($2,628.80) when medical necessity for separate procedure is documented

Mod 62

When to use: Use for co-surgery when two surgeons of different specialties work together as primary surgeons (e.g., neurosurgeon and plastic surgeon), each performing distinct portions of the nerve grafting procedure.

Reimbursement impact: Each surgeon receives 62.5% of the allowable ($1,643.00 per surgeon) when properly documented with each surgeon's operative note

Mod 78

When to use: Apply when returning to the operating room for a related procedure during the postoperative period, such as revision of nerve graft or additional grafting due to complications.

Reimbursement impact: Reimbursement reduced to intraoperative component only, typically 70% of base rate ($1,840.16), as postoperative care already paid

Common denials

Medical necessity denial claiming nerve grafting was 'routine' part of primary procedure (tumor resection, parotidectomy) rather than distinct reconstructive surgery.

How to appeal: Submit appeal with operative note highlighting unexpected nerve sacrifice or injury requiring grafting, comparison to CPT guidelines showing 15842 is separately reportable, and literature supporting immediate reconstruction improves outcomes. Include preoperative imaging showing tumor-nerve relationship if available.

Insufficient documentation of microsurgical technique - payer claims procedure could be performed without microscope and should be coded as simple nerve repair (64864-64865).

How to appeal: Provide operative note excerpts documenting microscope use with magnification levels, microinstruments used, microsurgical suture size (typically 8-0 to 10-0 nylon), and epineural coaptation technique. Reference CPT descriptor requiring 'microsurgical' technique and cite medical literature on technical requirements.

Bundling denial when billed with parotidectomy (42410-42426) or acoustic neuroma resection (61520), claiming nerve work is included in primary procedure.

How to appeal: Submit appeal citing CPT guidelines and NCCI edits showing 15842 is not bundled with primary procedure code. Document that nerve grafting is reconstructive surgery beyond tumor removal, performed after pathology confirmed and represents distinct additional work with modifier 59 appropriately applied.

Denial for multiple grafts or bilateral procedures claiming only one nerve graft per session is covered without additional supporting documentation of medical necessity.

How to appeal: Provide detailed operative note documenting each graft segment length, anatomic location, and clinical justification for multiple grafts (gap length exceeds single graft capability) or bilateral repair (simultaneous bilateral pathology). Include pre-operative nerve conduction studies showing bilateral dysfunction when applicable.

Frequently asked questions

What is the Medicare reimbursement rate for CPT code 15842 in 2025?

The 2025 Medicare national average reimbursement for CPT 15842 is $2,628.80 for both facility and non-facility settings. This rate is based on 81.27 total RVUs (41.01 work RVU + 32.75 practice expense RVU + 7.51 malpractice RVU) multiplied by the 2025 conversion factor of 32.3465. Actual reimbursement may vary by geographic locality based on GPCI adjustments.

Can CPT 15842 be billed with a parotidectomy or tumor resection code?

Yes, CPT 15842 can be billed separately with parotidectomy (42410-42426) or tumor resection codes when the nerve grafting represents distinct, additional work beyond the tumor removal itself. Documentation must clearly show the nerve grafting was necessitated by tumor involvement requiring nerve sacrifice and was not a routine component. Use modifier 59 to indicate a distinct procedural service and ensure the operative note details the separate nature of the reconstructive nerve work.

What documentation is required to support billing CPT 15842?

Documentation must include: confirmation of operating microscope use with magnification level, identification of donor nerve and harvest site, graft length measurements, recipient nerve identification, number of grafts used, microsurgical anastomosis technique with suture size (8-0 to 10-0), medical necessity justification, and pre-operative diagnosis with facial nerve palsy severity grading. The operative note should clearly differentiate microsurgical technique from simple nerve repair to prevent downcoding.

How many RVUs is CPT code 15842 worth in 2025?

CPT code 15842 has a total of 81.27 RVUs in 2025, consisting of 41.01 work RVUs, 32.75 practice expense RVUs (both facility and non-facility), and 7.51 malpractice RVUs. This high RVU value reflects the technical complexity, time intensity (typically 4-6 hours), and specialized training required for microsurgical facial nerve grafting procedures.

What is the difference between CPT 15842 and 64864 for nerve repair?

CPT 15842 specifically describes microsurgical nerve grafting for facial nerve palsy requiring harvest and interposition of donor nerve tissue, while 64864 describes direct suture repair of facial nerve without grafting. Use 15842 when the nerve gap requires grafting to bridge the defect (typically >5mm gaps) and microsurgical technique with operating microscope is employed. Use 64864 for direct primary nerve coaptation without grafting. The reimbursement for 15842 ($2,628.80) is significantly higher than 64864 due to the added complexity of graft harvest and placement.

What modifier should I use when billing 15842 bilaterally?

Use modifier 50 (bilateral procedure) when facial nerve grafting is performed on both sides during the same operative session. This increases reimbursement to 150% of the base rate, or $3,943.20 total for bilateral procedures. Each side must have separate documentation justifying medical necessity for bilateral repair, and the operative note should detail the distinct work performed on each facial nerve.

What are common reasons for denial of CPT 15842 claims?

Common denials include: (1) medical necessity denials claiming nerve grafting was routine part of primary procedure rather than distinct service, (2) insufficient documentation of microsurgical technique leading to downcoding to simpler nerve repair codes, (3) bundling denials when billed with parotidectomy or tumor resection without proper modifier use, and (4) lack of support for multiple grafts or bilateral procedures. Proper documentation of technique, medical necessity, and use of appropriate modifiers (59, 22, 50) prevents most denials.

Calculate with modifiers