Radiology CPT Code Structure
Radiology billing is built around a fundamental distinction that does not exist in most medical specialties: the separation of professional and technical components. Every radiology service has a global fee that splits into the professional component (physician interpretation, coded with modifier 26) and the technical component (equipment, technician, facility, coded with modifier TC). How you bill depends on whether you own the equipment, employ the interpreting physician, or both. Getting this split wrong is the most expensive coding error in radiology.
Diagnostic Imaging Codes
X-ray codes (70000-73599) are the highest-volume radiology codes. Chest X-ray 2-view (71046) reimburses approximately $31 for the global service, splitting into roughly $10 professional and $21 technical. Extremity X-rays (73060-73130) range from $20 to $45 global. The technical component generates most of the revenue because it covers equipment and facility costs.
CT scan codes (70450-72133) reimburse significantly more: CT head without contrast (70450) reimburses approximately $120 global ($40 professional, $80 technical). CT abdomen/pelvis with contrast (74178) reimburses approximately $280 global. MRI codes (70551-73723) represent the highest-value diagnostic imaging: brain MRI without contrast (70551) reimburses approximately $260 global, and lumbar spine MRI (72148) reimburses approximately $280.
Professional vs. Technical Billing
The billing model depends on the practice arrangement. Hospital-based radiologists bill only the professional component (modifier 26) because the hospital bills the technical component. Freestanding imaging centers bill the global code because they own the equipment and employ or contract with the interpreting radiologist. Teleradiology groups bill modifier 26 only because they provide interpretation services remotely.
Billing the wrong component is a compliance issue. A radiologist who interprets from a remote location but bills the global code is claiming technical component reimbursement for equipment they do not own. Payers audit this aggressively, and overpayment recovery for technical component claims billed without equipment ownership can be substantial.
Interventional Radiology Codes
Interventional radiology (IR) procedures generate the highest per-case revenue in the specialty. Image-guided biopsies (77012 for CT guidance, 77021 for MRI guidance), vascular access procedures (36556-36573), and drainage procedures (49405-49407) combine imaging guidance codes with procedure codes. The imaging guidance code and the procedure code are billed together, each with its own professional and technical split.
Contrast Administration
Contrast-enhanced studies require additional codes for contrast administration. Oral contrast preparation is typically not separately billable. IV contrast injection may be billed using 96374 (IV push) when the radiologist or radiology staff performs the injection. The contrast material itself is billed using HCPCS codes (A9575 for iodinated contrast, A9576-A9579 for MRI contrast agents).
Screening and Preventive Imaging
Screening mammography (77067) and low-dose CT lung screening (G0297 for Medicare, 71271 for commercial) have specific billing requirements. Screening exams use different codes than diagnostic exams of the same body part. Billing a diagnostic mammography code (77066) for a screening study, or vice versa, results in denial. The distinction is clinical: screening is performed on asymptomatic patients, diagnostic on patients with symptoms or prior abnormal findings.