The combined use of duplex ultrasonography and magnetic resonance angiography most accurately diagnosed carotid artery stenosis.

D e s c r i p t i o n o f t e s t s a n d d i a g n o s t i c s t a n d a r d DUS, MRA, and DSA were done within 4 weeks. The degree of stenosis on DUS was based on the peak systolic velocity (PSV) in the proximal internal carotid artery; analysis of DUS was based on a threshold of 70% stenosis, represented by a PSV of 270 cm/s. DSA was the diagnostic standard: A positive test result was defined as severe stenosis (70% to 99%) in the internal carotid artery on DSA. In the analyses, only stenosis measurements of the carotid artery on the symptomatic side were used.