SUMMARY
Doppler ultrasonography is a noninvasive. reliable method that can be used to analyze blood flow velocity. The introduction of Color Doppler allowed us, for the first time, to obtain simultaneous real-time bidimensional image and color-coded blood flow measurements of vessels beyond the resolution of other methods. This study introduces the use of Color Doppler in Brazil. describes the physical principles involved. the technique and main ophthalmic indications.