A lack of color along some image lines due to power Doppler signal saturation after contrast medium injection.
A region of very high blood flow velocity such as that extending downstream from vessel stenosis.
Small rapid irregularities in a waveform or an image display due to electronic noise, a mechanical disturbance, the supply voltage, changes in properties of components, etc.
A unit of energy. One joule is the amount of energy required to move an object with a force of 1 newton (N) over a distance of 1 m. 4.18 J = 1 calorie.