Principle of High-Speed Digital Subtraction Echography and the Potential for Clinical Applications

To improve time and spatial resolution of echography, we have developed a High-speed Digital Subtraction Echography. The principle is serial image subtraction of successive frames of high-speed B-mode echograms. This system elucidated: 1) initial myocardial contraction originating from the pacing point of an experimental ventricular premature contraction (VPC) in dogs. Substantially the same initial contraction appeared from the VPC focus in a human patient. 2) Local elasticity of arterial wall was assessed as the systolic fine radial extension. 3) Utilizing echoic particles in blood, the streamlines were also visualized.