Measurement of two-dimensional blood velocity vectors by the ultrasonic speckle projection technique

A technique has been developed for measuring the two in-plane components of blood velocity using ultrasound. The principle is based on analyzing a time sequence of successive images of the speckle pattern, and forming spatial projections of the resulting three-dimensional data set. The mathematics may be understood in terms of sections through a three-dimensional Fourier transform of the original data. The technique has been tested with data from a computer-controlled scanner using a tissue-mimicking phantom, and with data from a commercial ultrasound scanner using images of flowing blood in a jugular vein. In both cases, velocity vectors with many different orientations were measured, demonstrating the feasibility of the method. A less restrictive real-time implementation is suggested.