what is color flow doppler on echo
A Doppler ultrasound is a noninvasive test that can be used to estimate your blood flow through blood vessels by bouncing high-frequency sound waves (ultrasound) off circulating red blood cells. A regular ultrasound uses sound waves to produce images, but can't show blood flow. A Doppler ultrasound may help diagnose many conditions, including: 1  Blood clots. 2  Poorly functioning valves in your leg veins, which can cause blood or other fluids to pool in your legs (venous insufficiency). 3  Heart valve defects and congenital heart disease. 4  A blocked artery (arterial occlusion).