Radiology services are among the most utilized—and most scrutinized—departments in modern healthcare. Yet due to complex CPT/HCPCS codes, modifier usage, NCCI edits, and payer-specific policies, radiology claims often lead to high denial rates, underpayments, or post-payment audits.
This article outlines best practices in radiology billing and coding, from documentation through claims submission. It is designed to help hospitals, imaging centers, and physician groups maximize compliance, minimize denials, and ensure accurate reimbursement in 2025 and beyond.
1. Understanding the Unique Complexity of Radiology Billing
Radiology billing differs from most other specialties due to several layered components:
| Complexity | Explanation |
|---|---|
| Global vs. Professional/Technical | Radiology may be billed as global (both components) or split. |
| Multiple Modifiers | Common use of -TC, -26, -76, -77, -59, and -X{EPSU} for appropriate coding. |
| Bundling Rules (NCCI) | Procedures like fluoroscopy or contrast may be bundled depending on context. |
| Medical Necessity Guidelines | Imaging must meet LCD/NCD requirements to avoid denials. |
| Frequent Code Updates | CPT and HCPCS codes evolve yearly; failing to update can cause claim rejections. |
2. Best Practice #1: Accurate Documentation and Radiologist Collaboration
Clear documentation is the foundation of proper billing. Key principles include:
✅ Radiology Report Must Include:
- Study performed (e.g., MRI brain w/ contrast)
- Date of service and interpreting physician
- Clinical indication
- Findings and impressions
- Type of supervision if applicable
✅ Collaborate With Radiologists On:
- Ensuring dictation includes laterality, contrast use, and anatomical specifics
- Clarifying when comparison studies were reviewed
- Including details for incidental or unrelated findings (for separate billing)
3. Best Practice #2: Correct Use of Modifiers
Modifiers are critical in radiology. Using the wrong one—or omitting one—can result in denials or audits.
| Modifier | Meaning | When to Use |
|---|---|---|
| -26 | Professional component | Radiologist interpretation only |
| -TC | Technical component | Equipment and technician service only |
| -59 | Distinct procedural service | Two separate procedures, not normally billed together |
| -76 | Repeat procedure by same physician | E.g., multiple ultrasounds in same session |
| -77 | Repeat by different physician | Second radiologist interpretation |
| -91 | Repeat clinical diagnostic lab test | Valid for repeat diagnostic imaging |
| X{EPSU} | Subsets of -59 for Medicare | E.g., XE for separate encounter, XS for separate structure |
4. Best Practice #3: Stay Current on CPT and HCPCS Code Updates
The AMA revises CPT codes annually. Missing these changes leads to denials and compliance risk.
Radiology CPT Code Categories
- 70010–76499 – Diagnostic Imaging
- 77001–77022 – Interventional/Guidance Imaging
- 77261–77799 – Radiation Oncology (often billed through radiology depts)
- G-codes – HCPCS-specific codes for Medicare (e.g., G0279 for CT angiography)
2025 Notable Changes (Example)
| Code | Description | Change |
|---|---|---|
| 77089 | Quantitative CT for bone mineral density | New code added |
| 77091 | MRI of prostate with AI-based segmentation | New technology category |
| 76376 | 3D rendering with interpretation and report | Revised description |
📌 Tip: Subscribe to AMA CPT updates and your Medicare MAC’s update listservs.
5. Best Practice #4: Apply NCCI Edits and Unbundling Rules Correctly
The National Correct Coding Initiative (NCCI) governs what codes can be billed together.
Key Rules for Radiology:
- Ultrasound Guidance (76942) is often bundled into joint injections or biopsies
- Contrast Studies must use appropriate codes (e.g., 74177 for CT abdomen + pelvis w/ contrast)
- Vascular Studies like 93970 (venous ultrasound) are often mutually exclusive unless separate legs/sites
Tool: CMS NCCI Edit Lookup
Visit https://www.cms.gov/Medicare/Coding/NationalCorrectCodInitEd for code pair info.
6. Best Practice #5: Denial Prevention With Prior Authorization and Medical Necessity
Many radiology services require prior auth—especially high-cost exams like CT, MRI, PET.
Checklist Before Scheduling:
✅ Validate payer-specific prior auth requirements
✅ Confirm ordering provider documented clinical necessity
✅ Match diagnosis to payer LCD/NCD policy
✅ Ensure proper CPT is authorized—not just a generic “MRI”
Common Denial Reasons:
| Reason | How to Prevent |
|---|---|
| No authorization on file | Always verify auth approval ID |
| Diagnosis not medically necessary | Match clinical signs to LCD guidance |
| CPT mismatch with auth | Confirm auth matches modality, body part, contrast |
7. Best Practice #6: Use AI and Revenue-Cycle Tools for Accuracy
Modern radiology billing relies on automation to ensure accuracy and speed.
Recommended Tools:
- Computer-Assisted Coding (CAC): Auto-suggests CPTs from radiology reports
- Claim Scrubbers: Flag mismatches between ICD-10, CPT, and modifiers
- AI Prior Authorization: Predicts if a payer will require auth
- Denial Predictors: Analyze past data to flag likely-denied claims
- Radiology Information Systems (RIS): Capture modality, contrast, tech used, and route to coders
Example: A 2024 study showed AI-assisted radiology billing reduced denial rates by 38 % and decreased A/R days by 21.
8. Best Practice #7: Radiation Oncology & Interventional Radiology Coding
These subfields of radiology carry extra complexity due to time-based and multiple-session billing.
For Radiation Oncology:
- Use CPT 77261–77799
- Track simulation, planning, dosimetry, and treatment delivery separately
- Bill weekly treatment management (77427) only once per five fractions
For Interventional Radiology:
- Combine surgical + imaging codes
- Be aware of supervision and interpretation (S&I) coding rules
- Distinguish between diagnostic vs. therapeutic angiography
📌 Tip: Use vascular family maps and interventional coding references (e.g., ZHealth).
9. Best Practice #8: Regular Audits and Coder Education
Even experienced coders can miss nuances in radiology coding. Continuous training is vital.
Quarterly Audit Checklist:
✅ Sample 50 claims across modalities (CT, MRI, IR, mammo)
✅ Review code selection, modifiers, medical necessity
✅ Check match to documentation and dictation
✅ Look for overuse of -59, -26, and repeat procedures
Coder Education Must Include:
- New CPT/HCPCS and ICD-10 changes annually
- Real-world denial trends by payer
- Radiologist education sessions on “documentation gaps”
10. Sample Radiology Billing Workflow (Optimized)
[Order Entry] ➜ [Pre-auth Verification] ➜ [Exam Performed + Tech Notes Captured] ➜ [Radiologist Dictation] ➜ [Coding + Modifier Assignment] ➜ [Scrubbing + Edits] ➜ [Claims Submission] ➜ [Payment Posting + Denial Management] 📌 Tip: Every break in this chain increases claim error risk.
11. Radiology Billing KPIs to Track
| KPI | Target Benchmark |
|---|---|
| First-pass claim acceptance rate | ≥ 98 % |
| Initial denial rate (radiology) | ≤ 6 % |
| Days in A/R (radiology-specific) | ≤ 40 days |
| Underpayment rate (post-audit) | ≤ 2 % |
| Percentage of claims with modifiers | ≥ 70 % (varies by modality) |
12. Common Pitfalls (and How to Avoid Them)
| Pitfall | Solution |
|---|---|
| Billing technical and professional together inappropriately | Use global billing only when both are performed by same entity |
| Overusing Modifier -59 | Train coders on appropriate NCCI override scenarios |
| Not validating contrast use | Ensure radiology report confirms contrast given |
| Using outdated CPT codes | Annual code review and coding team retraining |
| Failing to separate procedures at different sites | Use XS modifier when billing for separate anatomical areas |
13. Regulatory Watch (2025–2026 Trends to Monitor)
| Trend | Expected Impact |
|---|---|
| Medicare’s AI-Aided Audit Expansion | AI will flag unusual modifier usage in radiology |
| Transparency in Imaging Pricing | Requires publishing outpatient imaging prices |
| ICD-11 adoption (projected 2026–27) | Future-proof your RIS/EHR systems |
| No Surprises Act – IDR expansion | Disputes on OON imaging will increase |
Conclusion
Radiology billing is both an art and a science. It requires expert understanding of procedure codes, medical necessity, NCCI edits, modifier rules, and payer-specific nuances. By following these best practices—and investing in automation, training, and proactive auditing—organizations can minimize denials, accelerate reimbursement, and stay compliant.
In 2025 and beyond, radiology billing success will be measured not just by speed, but by accuracy, adaptability, and audit-readiness.
