CTA Upper Extremity

Indications

• Traumatic vascular injury of the arm/forearm/hand
• Acute upper limb ischemia (embolism, thrombosis)
• Dialysis access planning or dysfunction
• Vasculitis, thromboangiitis, hypothenar hammer syndrome
• Tumor vascular encasement; free-flap planning

Patient prep

• IV access in the CONTRALATERAL arm — injecting the symptomatic side causes streak and venous contamination
• Symptomatic arm raised overhead, palm up (centers anatomy in the scan field); arm at side if trauma prevents raising
• Remove jewelry/metal from the studied arm
• Screen eGFR/contrast allergy

Contrast

Technique

• Coverage aortic root/arch through the fingertips of the symptomatic arm — includes the subclavian origin
• Pace the acquisition (don't outrun the bolus): distal forearm/hand arteries fill late; slow the table or add a delay for the distal station
• 100-120 kV; thin 0.625-1 mm recon; MIP and 3D VR of the arterial tree
• Immediate second pass through forearm/hand if distal vessels unopacified on the first

Series / Sequences

Key points

• Contralateral injection is the single most important setup detail — dense venous contrast in the studied arm can render the exam nondiagnostic
• Cover from the aortic root: proximal sources of embolism (arch, subclavian) are part of the question
• Distal runoff timing is variable in ischemia — a delayed second acquisition rescues apparently 'occluded' but slow-flow vessels
• Raise the arm overhead when possible for better centering, lower dose, and fewer torso artifacts

References