Brachiocephalic Artery Disease Progression Resulting in Complex Steal Phenomena

Severe brachiocephalic artery stenoses are relatively rare obstructions of the extracranial arteries and can cause significant changes to hemodynamics and spectral Doppler waveform patterns, complicating diagnosis. This case study presents disease progression from stenosis to occlusion and resulting complex steal phenomena extending to the contralateral upper extremity, which has not been widely reported. The sonographic findings of disease progression and collateral pathways were confirmed by magnetic resonance angiography and contrast-enhanced computed tomography.