Vascular studies of the legs for venous or arterial disease.

The basis of in-office evaluation of leg vascular disease involves Doppler ultrasound to estimate flow in arteries and veins. Arterial evaluation localizes sites of obstruction by segmental pressures obtained by Doppler signal assessment using pressure cuffs. Ankle compared with brachial arterial pressure is the most rapid screening test. Plethysmography permits more automated and sensitive analysis of pressure waveforms. Venous evaluation identifies sources of increased pressure transmitted by incompetent valves to surface veins causing varicosities and telangiectases. Doppler ultrasound permits sites of reverse flow (incompetent valves) to be localized, whereas plethysmography enables physiologic consequences of incompetent valves to be analyzed. Plethysmography with pressure cuff placement localizes deep system disease versus superficial disease, and rules out deep malfunction. When in-office diagnostic tests are equivocal, duplex ultrasound or more invasive tests should be considered.