Lin Qizhi, chief physician of the Department of Obstetrics and Gynecology, CuHK Hospital affiliated to Southeast University
Many expectant mothers are confused about ultrasound in pregnancy tests: should the "mass expulsion" (i.e., systemic prenatal screening of the fetus) be done in three or four dimensions in the second trimester? Is three-dimensional and four-dimensional really more advanced than two-dimensional? What is the difference between two-dimensional, three-dimensional and four-dimensional ultrasound, and how to choose?
Two-dimensional ultrasound: preferred for orthodontics. Two-dimensional ultrasound is a tangential imaging, although it is not stereoscopic imaging, but the resolution is high, and the judgment ability of fetal malformations is higher than that of three dimensions. Two-dimensional image is the fundamental basis for judging whether the fetus has malformations, and the final examination conclusion is also derived from the two-dimensional images, which is the preferred method for fetal malformation screening.
3D ultrasound: more stereoscopic. Three-dimensional ultrasound can provide three-dimensional images of the face of the fetus or other parts, and is an auxiliary means of two-dimensional technology. When the fetus is found to be abnormal on two-dimensional examination, the three-dimensional development can be further verified. Three-dimensional ultrasound can make up for the limitations of two-dimensional ultrasound and make more accurate judgments. For example, for malformations of fetal surface structures (such as cleft lip), three-dimensional ultrasound can be more intuitively presented in three dimensions and assess prognosis.
Four-dimensional ultrasound: the icing on the cake. Four-dimensional is a three-dimensional "dynamic three-dimensional" formed on the basis of three-dimensional, and its moving image allows expectant parents to see the activities in the fetal uterus, promote the cultivation of parent-child feelings, and add icing on the cake.
Therefore, two-dimensional ultrasound is the core means of prenatal screening, and three-dimensional and four-dimensional ultrasound are auxiliary means. Expectant mothers are reminded to try to avoid long, multi-count ultrasound examinations to prevent unnecessary consequences. ▲