Yes, it is technically possible but clinically impractical and not standard practice.
A "CT abdomen and pelvis with runoff" is inherently a CTA (computed tomography angiography) because the term "runoff" specifically refers to vascular imaging of the arterial tree from the abdomen through the pelvis and into the lower extremities. The "runoff" terminology itself denotes arterial evaluation, which requires IV contrast timing optimized for arterial phase imaging 1.
Understanding the Terminology
The confusion likely stems from nomenclature, but let me clarify:
- "Runoff" imaging is a vascular imaging term that specifically describes evaluation of arterial flow from proximal vessels (aorta) through distal vessels (lower extremity arteries) 1
- This examination requires IV contrast with arterial phase timing to visualize the vascular tree
- The studies in the literature consistently refer to "run-off CTA" as a single entity 2, 3, 4, 5
What You Can Actually Order
If you want non-angiographic imaging:
- Order a standard "CT abdomen and pelvis with IV contrast" (portal venous phase)
- Order a "CT abdomen and pelvis without contrast" if no vascular assessment is needed
If you want vascular assessment:
- "CTA abdomen and pelvis with bilateral lower extremity runoff" is the correct order 1
- This can be performed without imaging the abdomen/pelvis if aortoiliac disease is not a concern or already known 1
Clinical Context
According to ACR Appropriateness Criteria, CTA with runoff is specifically indicated for:
- Assessment of peripheral arterial disease and claudication 1
- Pre-procedural planning for revascularization 1
- Evaluation when stenosis >50% diameter needs detection (sensitivity/specificity 90-100%) 1
Common pitfall: The term "runoff" cannot be separated from angiographic technique. If you order "CT with runoff," radiology will perform it as a CTA with arterial phase timing, as this is the only way to evaluate arterial runoff 1, 3.