Two-dimensional color Doppler flow velocity profiles can be time corrected with an external ECG-delay device.
Although two-dimensional ultrasound color flow imaging is often considered to be a real-time technique, the acquisition time for two-dimensional color images may be up to 200 msec. Time correction is therefore necessary to obtain correct flow velocity profiles. We have developed a time-correction method in which a specially designed unit detects the QRS complex from the patient and creates a trig pulse that is delayed incrementally in relation to the QRS complex. This trig pulse controls the acquisition of the ultrasound images. A number of consecutively delayed images, with known incremental delay between the sweeps, can thus be stored in the memory of the echocardiograph and transferred digitally to a computer. The time-corrected flow velocity profile is obtained by interpolation of data from the time-delayed profiles. The system was evaluated in a Doppler string phantom test. With this technique it is possible to study time-corrected flow velocity profiles without the need to alter existing ultrasound Doppler equipment.
Eidenvall
L
L
Department of Biomedical Engineering, University of Linköping, Sweden.
Sjöberg
B J
BJ
Ask
P
P
Loyd
D
D
Wranne
B
B
D001783:Blood Flow Velocity; D015150:Echocardiography, Doppler / Q000379:methods*; D004562:Electrocardiography / Q000295:instrumentation*; D006801:Humans; D012815:Signal Processing, Computer-Assisted; D013995:Time