4D ultrasound
In 4D ultrasound fetal scanning, however, instead of the sound waves being sent straight down and
reflected back, they are sent at different angles. The returning echoes are processed by a sophisticated
computer program resulting in a reconstructed three-dimensional volume image of the fetus's surface or
internal organs, in much the same way as a CT scan machine constructs a CT scan image from multiple x-
rays.
4D ultrasound is a medical ultrasound technique, often used in obstetric ultrasonography (during
pregnancy), providing three-dimensional images of the fetus.
There are several different scanning modes in medical and obstetric ultrasound. The standard common
obstetric diagnostic mode is 2D scanning.
