I need some help to clarify this situation. Radiology is telling me that they are billing both 70450 and 70460 because they were performed a little over an hour apart. Reason for the first scan was left-sided facial weakness, reason for the next w/contrast was possible dural mass.
Hi - I am a CT tech and a coder. Let me explain this:
In this case, you
CANNOT default to
70470.
- 70470 is only used when the exam is ordered and performed as a single study protocol: CT head without contrast immediately followed by with contrast, same accession, same indication, same encounter.
- What happened here is different:
- First scan (70450, without contrast): ordered for left-sided weakness.
- Second scan (70460, with contrast): ordered later because of a new finding/concern (possible dural mass), which can only be diagnosed with contrast.
- They were performed at different times, under different clinical indications, and will have separate accession numbers.
- - this link explains accession numbers.
Because of that, it is
not a “without → with” combo study. It is
two separate encounters on the same date of service.
Local Coverage Determination (LCD) for CT of the Head
The relevant LCD for CT head and neck imaging is
L37373, titled
“MRI and CT Scans of the Head and Neck”, which includes CPT codes
70450,
70460, and
70470 among others (
Providers Care Billing LLC,
Centers for Medicare & Medicaid Services).
NCCI Edit Relationship
- Column 1 Code: 70460 (with contrast)
- Column 2 Code: 70450 (without contrast)
- Modifier Indicator: 1 → meaning you can bypass the edit with an NCCI-associated modifier if criteria are met.
What this means:
- If both are reported on the same day of service, 70460 is the payable Column 1 code.
- 70450 is the Column 2 code, which would normally be denied unless you append an appropriate modifier (like XE for a truly separate encounter).
- The modifier attaches to the Column 2 code (70450) — not the Column 1.
How to apply here:
- If the two exams were truly separate encounters (different accessions, different clinical indications, not part of the same continuous study), then:
- Bill 70460 normally.
- Bill 70450 with modifier XE to show it was distinct.