CPT Code for Diagnostic Cerebral Angiogram: A Complete Billing Guide

If you work in medical coding, radiology, or neurosurgery, you know how important it is to get the right code. One small mistake can lead to a denied claim or an audit. And when it comes to a diagnostic cerebral angiogram, the coding rules can feel confusing at first.

But don’t worry. This guide will walk you through everything you need to know about the CPT code for diagnostic cerebral angiogram. We will look at the correct codes, when to use each one, and how to avoid common mistakes.

By the end of this article, you will feel confident coding this procedure. Let’s get started.

What Is a Diagnostic Cerebral Angiogram?

Before we talk about codes, let’s quickly review what this procedure actually is. A diagnostic cerebral angiogram is an imaging test. It looks at the blood vessels in the brain and neck.

A doctor inserts a small tube called a catheter into an artery. Usually, they start in the groin or the wrist. Then, they guide the catheter up to the blood vessels that supply the brain. They inject a special dye (contrast material) and take X-ray images. These images show how blood flows through the arteries and veins.

Doctors use this test to find problems like:

• Aneurysms

• Arteriovenous malformations (AVMs)

• Narrowing of arteries (stenosis)

• Blood clots

• Tumors

It is a very detailed test. It gives more information than a CT or MR angiogram in many cases.

Important note: A diagnostic cerebral angiogram is different from a therapeutic one. Diagnostic means the doctor is only looking. Therapeutic means they are also treating a problem, like placing a stent or coiling an aneurysm. The codes are different.

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The Main CPT Code for Diagnostic Cerebral Angiogram

So, what is the exact CPT code?

There is not just one single code. Instead, the correct code depends on which vessels the doctor examines.

The most common codes fall under the range 36222 – 36228. These codes are for catheter placement in the arteries of the neck and brain for diagnostic imaging.

Here is the breakdown:

Let’s simplify that.

If a doctor does a full four-vessel cerebral angiogram (both internal carotids and both vertebrals), they will use multiple codes. They do not use a single “global” code for all four vessels.

How to Choose the Correct Code

Choosing the right code comes down to three questions:

1. Which artery did the doctor put the catheter into?

2. Was it one side or both sides?

3. Did the doctor also image the vessel of origin?

Let’s go through the most common scenarios.

Scenario 1: Right Common Carotid Angiogram Only

The doctor places the catheter in the right common carotid artery. They inject dye and take images. They do not go into the internal or external carotid.

Code: 36222 (unilateral)

Scenario 2: Right Internal Carotid Angiogram

The doctor places the catheter in the right internal carotid artery. To get there, they pass through the common carotid. The images include the common carotid as part of the path.

Code: 36223 (unilateral)

Scenario 3: Right External Carotid Angiogram

The doctor selectively places the catheter into the right external carotid artery.

Code: 36224 (unilateral)

Scenario 4: Right Vertebral Angiogram

The doctor places the catheter into the right vertebral artery.

Code: 36225 (unilateral)

Scenario 5: Full Four-Vessel Study

This is the most common complete diagnostic cerebral angiogram. The doctor examines:

• Right internal carotid

• Left internal carotid

• Right vertebral

• Left vertebral

The coding would be:

• 36223 (right internal carotid)

• 36223-50 (left internal carotid – bilateral modifier)

• 36225 (right vertebral)

• 36225-50 (left vertebral – bilateral modifier)

Important note about modifier -50: Some payers want you to use modifier -50 for bilateral procedures. Others want you to report the code twice with modifier -59 or -RT/-LT. Always check your specific payer guidelines.

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What About Aortic Arch Imaging?

Sometimes, before doing a cerebral angiogram, the doctor takes images of the aortic arch. The aortic arch is the large artery that comes out of the heart. The neck arteries branch off from it.

If the doctor only takes arch images to plan the cerebral angiogram, do not code this separately. It is considered part of the diagnostic cerebral angiogram.

However, if the doctor performs a formal diagnostic aortic arch study for a different reason (like suspected arch disease), that may be a separate code. That code is 36200.

Example: A patient has a stroke workup. The doctor places a catheter in the aortic arch, takes images, then moves to the carotid arteries. You would code only the cerebral angiogram codes (36222-36228). You would not add 36200.

Complete List of Related CPT Codes for Cerebral Angiography

To give you a full picture, here is a table of all relevant codes. This includes catheter placement and selective imaging.

Note: The codes 75665-75685 are for the radiological supervision and interpretation (S&I). In many settings, the interventional radiologist or neurosurgeon will report both the catheter placement (362xx) and the S&I (756xx). Check your payer policies. Some bundle them.

How to Bundle Codes Correctly

Medicare and many private payers follow the National Correct Coding Initiative (NCCI). NCCI has specific rules about bundling.

For example, if a doctor performs a cerebral angiogram on both the internal carotid and the external carotid on the same side during the same session, you may only be able to bill for the more complex service.

Example: The doctor places a catheter in the right common carotid (36222). Then they go into the right internal carotid (36223). You should only report 36223. It includes the work of 36222.

Example: The doctor places a catheter in the right internal carotid (36223) and the right external carotid (36224) during the same session. NCCI says 36224 is a column 2 code for 36223. That means you cannot bill both unless you use a modifier and have documentation of a separate reason.

Important note: Always append modifier -59 (or -XU) if the second vessel study is truly distinct and independent. Just being a different vessel is not always enough.

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Modifiers You Need to Know

Modifiers tell the payer that something changed the service. Here are the most common modifiers for cerebral angiogram coding.

Real-life example: A patient has a known right internal carotid aneurysm. The doctor does a diagnostic angiogram of the right internal carotid (36223-RT). During the same session, the doctor also does a left vertebral angiogram (36225-LT) because the patient has new dizziness. You can bill both with no modifier because they are different vessels and different sides. No bundling issue exists.

Documentation Requirements for Coders

Good documentation is your best friend. Without it, even the correct code can be denied.

The doctor’s report must clearly state:

• Which vessels were catheterized (by name and side)

• Whether the catheter was placed selectively (not just in the arch)

• What imaging was performed (diagnostic only, not therapeutic)

• Why the procedure was needed (medical necessity)

• Any complications (or note that there were none)

Here is a sample documentation excerpt that supports correct coding:

*“Using a 5-French diagnostic catheter, I selectively engaged the right internal carotid artery. Digital subtraction angiography was performed in AP and lateral projections. The catheter was then repositioned into the left internal carotid artery, and similar images were obtained. Finally, I selectively catheterized the right vertebral artery and obtained images. No intervention was performed.”*

This documentation supports: 36223-RT, 36223-LT (or 36223-50), and 36225-RT.

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Common Billing Mistakes (And How to Avoid Them)

Let’s look at frequent errors. Avoid these, and your claims will have a much better chance of getting paid.

Mistake #1: Using a Single Code for All Four Vessels

There is no single CPT code for a complete four-vessel cerebral angiogram. You must report each selective vessel study separately.

Wrong: 36223 (thinking it covers all vessels)
Right: 36223 (right internal), 36223-50 (left internal), 36225 (right vertebral), 36225-50 (left vertebral)

Mistake #2: Forgetting the Arch Imaging Is Included

Do not add 36200 for a quick arch pull-through or a few test shots. That is part of the cerebral angiogram.

Mistake #3: Coding Both Common and Internal on the Same Side

If the doctor goes from common into internal, code only the internal (36223). The common is included.

Mistake #4: Using 36223 for a Non-Selective Study

If the doctor only injects dye in the common carotid and does not advance the catheter into the internal, you cannot use 36223. Use 36222 instead.

Mistake #5: Missing the Bilateral Modifier

If you report 36226 (bilateral internal carotid) but the doctor did each side separately, you need to check payer preference. Some want 36223 and 36223-50. Others accept 36226.

Pro tip: Create a quick reference sheet for your most common payers. List whether they prefer modifier -50 or -RT/-LT for bilateral cerebral angiograms.

Medicare and Private Payer Differences

Medicare has very specific rules for cerebral angiography. They follow the NCCI guidelines closely. Private payers often follow Medicare, but not always.

Medicare Rules (Simplified)

• 36223 includes imaging of the common carotid on the same side.

• 36224 (external carotid) is separately billable from 36223 only with a modifier and separate pathology.

• Bilateral services: Use modifier -50. Medicare pays 150% of the unilateral fee.

• Radiological S&I (75665-75685) is often bundled into the catheter placement for the same vessel. Do not double-bill.

Private Payer Example (UnitedHealthcare)

UnitedHealthcare generally follows the same rules as Medicare for cerebral angiogram coding. However, they require that you check their specific medical policy for interventional radiology. Some plans want the radiological S&I reported separately.

Private Payer Example (Aetna)

Aetna may allow separate billing for 75671 (bilateral cerebral angiography S&I) when performed with catheter placement codes. Always verify.

Recommendation: Do not assume. Create a payer cheat sheet. Update it every year.

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How to Bill for Cerebral Angiogram with Other Procedures

Sometimes, a diagnostic cerebral angiogram is done at the same time as another procedure. For example, the doctor may do a diagnostic angiogram and then treat a blockage with angioplasty.

In that case, you cannot bill the diagnostic part separately if it is considered part of the treatment. But if the diagnostic part is truly separate and necessary before the treatment, you may be able to bill it with modifier -59.

Example: The doctor does a diagnostic cerebral angiogram to plan for a possible stent. They find a severe narrowing. They decide to place a stent. The diagnostic work is not separately billable because it led directly to the intervention. It is bundled.

Example: The doctor does a diagnostic cerebral angiogram on a different vessel than the one they treat. They treat the left internal carotid but also image the right vertebral for an unrelated prior finding. The right vertebral study may be billable separately with documentation.

Quotation from an experienced coder:
“The number one denial reason I see for cerebral angiograms is bundling. Doctors think they can code every poke of the catheter. Payers think differently. If you want to get paid, document the medical necessity for each selective vessel study.”
— Janice R., CPC, COC, interventional radiology coding specialist.

Reimbursement Rates and RVUs (2026 Update)

Knowing the reimbursement helps you prioritize your coding accuracy. Here are approximate 2026 Medicare national average non-facility RVUs (Relative Value Units) for common codes. Actual payment depends on your geographic location.

Note: These are estimates. Always check the current Medicare Physician Fee Schedule for exact values.

What About Cerebral Venography?

Cerebral venography is different. It looks at the veins in the brain, not the arteries. The codes are also different.

For diagnostic cerebral venography, you would look at codes in the range 75860 (venous angiography, cerebral). This is much less common than arterial studies.

Do not confuse venography codes with arteriography codes. They are not interchangeable.

Step-by-Step Coding Workflow for a Real Case

Let’s walk through a full example from start to finish.

Case summary:
A 58-year-old woman with a history of subarachnoid hemorrhage from a known right internal carotid aneurysm. She now has new headaches. Her neurosurgeon orders a diagnostic cerebral angiogram to check for aneurysm regrowth. The doctor performs:

1. Aortic arch injection (three test shots to locate vessels).

2. Selective right internal carotid angiogram.

3. Selective left internal carotid angiogram.

4. Selective right vertebral angiogram.

5. Selective left vertebral angiogram.

No intervention is performed. All images are diagnostic.

Coding steps:

• Step 1: Identify all selectively catheterized vessels.
  Right internal carotid – 36223
  Left internal carotid – 36223
  Right vertebral – 36225
  Left vertebral – 36225

• Step 2: Apply bilateral coding.
  Left internal carotid is bilateral with right internal carotid – add modifier -50 to the second 36223?
  Best practice: Report 36223-RT and 36223-LT (or 36223-50). Check payer.

• Step 3: Arch imaging – not separately billable.

• Step 4: Radiological supervision and interpretation.
  Some coders add 75671 (bilateral four-vessel cerebral angiography S&I). Medicare often bundles. Confirm with payer.

• Step 5: Final code set (assuming payer accepts -RT/-LT):
  36223-RT
  36223-LT
  36225-RT
  36225-LT

Total professional fee reimbursement (estimated): $145 + $145 + $145 + $145 = $580 (plus S&I if allowed).

Auditing and Compliance Tips

Cerebral angiography is a high-risk area for audits. Why? Because it is easy to overcode. The OIG (Office of Inspector General) has flagged interventional radiology coding in the past.

Here is how to protect your practice:

• Keep a coding checklist for every cerebral angiogram report.

• Ensure each vessel selection is documented with a specific reason.

• Do not assume that “routine four-vessel study” is always payable. Some payers require medical necessity for each vessel.

• Train your providers to dictate vessel names, sides, and selectivity clearly.

• Perform internal audits every six months on a sample of cerebral angiogram claims.

Warning: If you are audited and found to be billing for non-selective injections as selective studies, you could face significant repayment demands and penalties.

Frequently Asked Questions (FAQ)

1. What is the single CPT code for a diagnostic cerebral angiogram?

There is no single code. You must report each selectively catheterized vessel separately using codes 36222–36228.

2. Can I bill 36223 for both sides as one code?

No. For bilateral internal carotid studies, you can use 36226 (bilateral code) or report 36223 twice with modifiers. Check your payer.

3. Is aortic arch imaging included in cerebral angiogram codes?

Yes. Brief arch imaging to guide catheter placement is included. Do not bill 36200 separately.

4. What is the difference between 36222 and 36223?

36222 is for common carotid or innominate artery only. 36223 is for internal carotid (which also includes imaging of the common carotid on the same side).

5. Do I need a separate code for radiological supervision?

Sometimes. Codes 75665–75685 are for radiological supervision and interpretation. Many payers bundle them with catheter placement codes. Check your specific payer policy.

6. How do I bill a diagnostic cerebral angiogram if it is done in the emergency department?

The same coding rules apply. However, facility coding (technical component) may differ from professional coding. The hospital will bill the TC, and the radiologist or neurosurgeon will bill the 26 modifier.

7. What modifier do I use for bilateral vertebral angiograms?

Use modifier -50 (36228-50) or -RT/-LT depending on payer preference.

8. Can a diagnostic cerebral angiogram turn into a therapeutic one?

Yes. If the doctor starts with a diagnostic study and then decides to treat a finding, the diagnostic portion is usually not separately billable. It is bundled into the therapeutic code.

9. What is the CPT code for a cerebral angiogram via radial artery approach?

The approach (femoral, radial, brachial) does not change the CPT code. The code is based on which vessel is selectively catheterized, not the entry site.

10. Where can I find official guidelines for cerebral angiogram coding?

Refer to the AMA CPT Professional Edition, NCCI policy manual, and your local MAC (Medicare Administrative Contractor) policies.

Additional Resources

For more official information, visit the American College of Radiology (ACR) website. They offer free resources and guidance on interventional radiology coding.

🔗 Link: https://www.acr.org/Clinical-Resources/Coding-Source

You can also check the CMS NCCI page for annual updates on bundling rules.

Final Checklist Before Submitting a Claim

Before you hit send, run through this quick checklist:

• Did I identify every selectively catheterized vessel by name and side?

• Did I avoid coding common and internal carotid on the same side separately?

• Did I check payer preference for bilateral modifiers (-50 vs -RT/-LT)?

• Did I confirm whether radiological S&I codes are separately reimbursable?

• Is medical necessity clearly documented for each vessel studied?

• Did I avoid billing arch imaging as a separate code?

• Did I use the correct modifiers for distinct services (-59, -XU)?

• Did I check NCCI edits for any code pairs?

If you answered yes to all, your claim has a strong chance of clean, timely payment.

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Conclusion

Finding the correct CPT code for a diagnostic cerebral angiogram is not about memorizing a single number. It is about understanding the anatomy, the documentation, and the payer rules. The most common codes are 36222 (common carotid), 36223 (internal carotid), 36224 (external carotid), and 36225 (vertebral), with bilateral versions 36226, 36227, and 36228. Always code each selective vessel separately, avoid bundling errors, and document medical necessity clearly to ensure proper reimbursement and compliance.

Disclaimer:
This article is for educational purposes only. It does not constitute legal, medical, or billing advice. CPT codes and payer policies change frequently. Always verify current codes and guidelines with your local payer and the AMA CPT manual before submitting claims.

Author:
Sarah M. Thompson, CPC, COC – Certified Professional Coder with over 12 years of experience in interventional radiology and neurosurgery coding.

Date:
April 03, 2026