Angiography means the imaging of veins and arteries. Without the need of X-rays, vessels and their surrounding tissue can be depicted with different methods including Doppler techniques to measure blood flow.

(Doppler look angle) The angle of incidence is the angle at which the ultrasound beam strikes an interface, or the angle at which the Doppler beam intersects the blood flow. Doppler signals are best obtained at angles of 60° or less.

See also Snells Law.

From SIUI Inc.;
'Dedicated to ultrasound industry, Shantou Institute of Ultrasonic Instruments, Inc. (SIUI) has launched Apogee 3500, the Digital Color Doppler Ultrasound Imaging System.
With latest imaging technologies, high-definition image quality and excellent practical functions, the Apogee 3500 offers optimal solutions for clinical ultrasonic examination.'

'The Apogee 3500 is available with many high-density, super broadband and multi-frequency probes, such as convex, micro-convex, linear, vaginal, rectal and phased array probes, which are widely applied for different clinical diagnoses, including abdomen (liver, kidney, gall-bladder, pancreas), gynecology (uterus, ovary), obstetrics (early pregnancy, basic OB, complete OB, multi gestation, fetal echo), cardiology (adult and pediatric cardiology), small parts (thyroid, galactophore, testicles, neonate), peripheral vascular and prostate.'

The ultrasound bandwidth describes the number or range of frequencies. The reflected Doppler bandwidth increase when the Doppler beam strikes red blood cells traveling at many different speeds (as in turbulent flow).

See also Q-value.

The beam vessel angle is between the axis of the ultrasound beam and the axis of a vessel lumen. This angle is equal to the Doppler angle when flow is parallel to the vessel axis.
Also called angle of attack.