How to Bill for MRI, CT, and Ultrasound Correctly

Getting paid for diagnostic imaging is trickier than it looks. You might have the right scan, the right patient, and the right insurance, but one missing modifier or documentation gap can hold up payment for weeks. MRI, CT, and ultrasound billing have their own set of rules, and knowing them makes the difference between clean claims and constant rejections.

If your practice handles radiology services, you already know how frustrating denials can be. But here’s the good news: most billing errors are preventable once you understand what payers actually want to see.

Understanding Technical and Professional Components

Every scan splits into two billable parts:

• Technical Component (TC): The “doing” part covering equipment, supplies, and the tech running the machine. If you own the scanner and employ the operators, you bill the TC.
• Professional Component (PC): The “reading” part, where the radiologist interprets results and writes the report.

When one entity handles both, they bill globally without modifiers. When separate, use modifier 26 for professional services and TC for technical. Understanding radiology CPT billing codes helps you apply the right modifier.

Common CPT Codes You Need to Know

Pick the wrong CPT code and your claim goes straight to the rejection pile. Here are the codes that come up most often:

Imaging Type	Common Procedures	CPT Code Range
MRI	Brain without contrast	70551
	Brain with and without contrast	70553
	Spine studies	72141-72158
	Abdomen/Pelvis	74181-74183
CT Scan	Head imaging	70450-70498
	Chest	71250-71270
	Abdomen and pelvis (combined)	74177
	CT Angiography	70496-75574
Ultrasound	Complete abdomen	76700
	Limited abdomen	76705
	Obstetric imaging	76801-76817
	Vascular studies	93970-93971

The contrast factor matters a lot here. If your radiologist used IV contrast material, that changes the code completely. Billing 70551 when 70553 was actually performed means you’re leaving money on the table. And seriously, these kinds of radiology billing mistakes add up fast when you’re processing dozens of claims daily.

Billing MRI Procedures

MRI reports must explicitly state contrast use with phrases like “with intravenous contrast” or “without contrast material.” Just “MRI brain” won’t work.

For multiple MRI studies in one visit (brain and spine), bill each separately, but check payer bundling rules first. Some insurers bundle certain combinations, others don’t. Link each scan to a legitimate diagnosis code. “Chronic headaches” works; “patient request” doesn’t.

CT Scan Billing Best Practices

The biggest CT billing mistake? Double-billing abdomen and pelvis scans. Use 74177 for combined studies instead of billing separately. CT angiography has different codes from regular CT scans. Whatever the radiologist documents determines the code.

Only IV contrast counts for “with contrast” billing. Oral or rectal contrast alone still uses the “without contrast” code. The report must specifically mention intravenous administration.

Ultrasound Documentation Requirements

With ultrasound, the key question is: complete or limited? A complete abdominal ultrasound (76700) requires documentation of the liver, gallbladder, common bile duct, pancreas, spleen, kidneys, and upper abdominal aorta. Missing one organ means you can only bill the limited code (76705).

OB ultrasounds need gestational age, visit type, and fetal position. Missing details lead to undercoding or rejections.

Contrast Media Billing

Contrast material can be billed separately using HCPCS Q codes (Q9965-Q9967 for low osmolar contrast). Hospital outpatient departments usually can’t bill contrast separately under OPPS since it’s packaged into the procedure. But freestanding centers and physician offices can bill these codes for separate reimbursement. Document the exact amount used in milliliters.

Medical Necessity and Documentation

Insurance companies scrutinize imaging claims closely. They want a provider order with a real clinical reason, ICD-10 diagnosis codes that match the procedure, details about the scan and contrast use, and a complete radiologist interpretation.

The diagnosis and procedure codes must match logically. A brain MRI for “headache” (R51.9) works. One for “routine physical” gets denied instantly.

Prior Authorization Requirements

Skipped prior authorization is the top reason imaging claims get denied. Most plans require it for MRI and CT scans, some for ultrasounds, too. Before scheduling, verify if the CPT code needs authorization, check network status, and note any frequency limits.

Keep good records of everything: the auth number, when you got it, and who approved. Something changes down the line? Get a fresh authorization. Don’t assume the old one covers you. Managing prior authorization the right way saves you from months of back-and-forth over delayed payments.

Avoiding Common Billing Errors

Here are the mistakes that cost practices the most: leaving off modifiers 26 or TC when you’re splitting components, billing procedures separately when there’s a combined code (like using 74150 and 74160 separately instead of just 74177), claiming both components when you only performed one, not documenting contrast properly, and skipping payer bundling rules.

Regular audits catch these before they become problems. Even better, get billing software that spots errors automatically. Way easier to fix things before the claim goes out than to chase down denials after the fact.

Handling Claim Denials

First thing when you get a denial? Look at that denial code. It tells you exactly what went sideways: authorization was missing, you picked the wrong CPT code, documentation wasn’t enough, or the modifier was off. Figure out what broke, fix it quickly, and get that claim back in before you hit the deadline.

Watch for patterns too. Same procedure getting denied over and over? You’ve got a bigger problem than one bad claim. Professional denial management helps spot these patterns and fix whatever’s causing them.

Staying Current with Code Changes

CPT codes change every January. Review the updates and train your staff on what changed. Payers also update policies throughout the year, so subscribe to their bulletins or work with someone who tracks these changes. Staying informed keeps claims clean and cash flowing.

Undercoding vs. Upcoding Risks

Undercoding means billing for less than what you did. Bill 74177 (without contrast), when you actually did 74183 (with contrast), and you lose money on the contrast and enhanced imaging.

Upcoding is billing for more than documented. Bill a complete ultrasound (76700) when you only did a limited study (76705), and you’re asking for audit trouble. Code exactly what the documentation supports.

Bilateral Procedures

For bilateral imaging, use modifiers RT (right) and LT (left) on separate claim lines. Don’t use modifier 50 since many payers deny it. The report must document that both sides were examined separately.

Getting Expert Help with Radiology Billing

Between code updates, authorizations, documentation, and denials, radiology billing gets complex fast. Many practices find that professional radiology billing services reduce headaches and increase revenue.

When you work with specialists who know imaging billing, you get clean first-time claims, proper authorization handling, faster payments, and lower denial rates. If you’re fighting insurance companies more than seeing patients, consider outsourcing. The right partner optimizes your revenue cycle so you collect what you’ve earned.