METHOD FOR PRENATAL DIAGNOSIS OF DOWN SYNDROME IN II TRIMESTER OF PREGNANCY Russian patent published in 2025 - IPC A61B8/08 A61B17/42 

FIELD: medical science.

SUBSTANCE: invention refers to medicine, namely to obstetrics and gynaecology, ultrasonic diagnostics, and can be used for prenatal diagnostics of Down syndrome (DS) in the II trimester of pregnancy. From 19th to 21st week of pregnancy inclusive, ultrasound examination of foetal brain structures is carried out. Foetal profile is visualized in sagittal scanning plane, profile image occupies not less than 2/3 of screen with visualization of such structures as: frontal bone, corpus callosum along the full length, cerebellar vermis, hard palate and chin. A callosal frontal distance (CFD) that is a distance from a knee of a corpus callosum to an inner surface of frontal bone is measured 3 times. An external border of the horizontal caliper lines is found in a junction of the anechoic corpus callosum and the echogenic cerebral parenchyma, the echogenic cerebral parenchyma and the hyperechoic frontal bone; the greatest result is taken into consideration. And if: at term from 19th to 20th week of pregnancy, CFD is less than 12.1 mm, at term from 20th to 21st week of pregnancy, CFD is less than 12.2 mm, if the CFD is less than 12.5 mm on 21st week of pregnancy, DS is diagnosed in the foetus.

EFFECT: technique enables the most accurate and easy-to-implement prenatal diagnosing of DS ensured by measuring the callosal-frontal distance.

1 cl, 9 dwg, 1 tbl, 2 ex