Duplex ultrasound imaging: vascular applications.

A recently developed duplex ultrasonic imaging system that combines high-resolution real-time imaging with simultaneous Doppler analysis provides accurate evaluation of hemodynamically significant occlusive vascular lesions. This system was used in the evaluation of the extracranial carotid arteries, iliofemoral arteries, and hemodialysis shunts. The system obtains information regarding blood velocity, lumen area, plaque composition and ulceration, and hemodynamic turbulence. A total of 140 patients with hemodynamically significant lesions diagnosed by this method was evaluated angiographically. Correlation between the two modalities yielded a sensitivity of 0.94, a specificity of 0.88, and an overall accuracy of 0.92. The diagnostic information obtained can be used to differentiate potential surgically correctable lesions from those that require medical therapy or follow-up.