ABSTRACT
Formula .................................................................................................... 274 11.5 Flow Measurement ............................................................................................................ 275
11.5.1 Ultrasonic Methods for Measuring Flow (Particularly of Blood) ................... 275 11.5.1.1 Basic Properties of Ultrasound ............................................................. 275 11.5.1.2 Production and Detection of Ultrasound ............................................ 275 11.5.1.3 Doppler Principle .................................................................................... 276 11.5.1.4 Transit Time ............................................................................................. 276
The electrical events within the heart, together with the pressures and £ows throughout the circulation, offer a great deal of useful data upon which accurate diagnosis of abnormality can be obtained. Much of this monitoring is of continuous data, and analysis can be carried out in real time, permitting prompt intervention when necessary.
