What is the difference between 4D color Doppler ultrasound and 3D color Doppler ultrasound?

Three-dimensional color Doppler ultrasound is also based on two-dimensional color Doppler ultrasound to obtain a series of two-dimensional images. After computer processing, three-dimensional, intuitive effects can be obtained. This is three-dimensional color Doppler ultrasound. Four-dimensional color Doppler ultrasound is real-time three-dimensional color Doppler ultrasound, that is, dynamic three-dimensional color Doppler ultrasound. For pregnant women after is to do four-dimensional color ultrasound, or three-dimensional color ultrasound, pregnant women will be more entangled, as long as it is taken by the ultrasound machine is relatively high-end or the doctor's operation technology level is relatively high, whether it is four-dimensional color ultrasound and three-dimensional color ultrasound, can obtain the baby's intuitive photos can be carried out fetal row abnormal screening.