What is done?
When measuring the nuchal fold, the nuchal fold of the child is assessed as the name suggests. The skin in the neck area is assessed by ultrasound. The terms nuchal density measurement and nuchal translucency measurement describe other structures of the nuchal fold examined in addition to thickness.
The neck area of the unborn child is assessed by means of an ultrasound examination. The examination itself is very uncomplicated and very low-risk for both mother and child and does not involve any greater risk than other ultrasound examinations during the screening routine. The ultrasound is performed either through the mother’s vagina or through the abdominal wall, depending on the position in which the child’s neck can best be assessed.
The thickness of water accumulation in the nuchal fold and its shading is measured in the ultrasound image. Ultrasound consists of emitted sound waves similar to the echo sounder on ships. The sound waves cannot be heard by humans, since the human ear is far from being able to hear all sound waves.
In shipping, the emitted waves are reflected by surrounding boats as they bounce off them and are reflected back. From the returning signals a boat can then recognize which boats are in its surroundings. This principle works in the same way for ultrasound examinations in medicine.
The reflected and reflected waves from different tissues can be picked up by the ultrasound device and the image of the child calculated from the reflected waves from the device is displayed on the screen. Different types of tissues reflect the waves to different degrees, so that the different reflected waves are displayed on the screen in different colors. The color can then be used to draw conclusions about the tissue to a certain extent.
Liquids hardly reflect any rays and appear black on the screen of the ultrasound machine, for example, amniotic fluid. Otherwise light tissue can appear darker if there is liquid in it.It is precisely this property that is exploited here, as fluid collects in the tissue of the foetus. The reason for this is the kidneys and excretory organs, which are not yet sufficiently mature in the fetus.
For this reason, the fluid is still deposited in the tissue. The liquid itself is completely harmless for the child, the decisive factor is the amount of stored liquid and a possible increase in the thickness of the nuchal fold due to the deposits. During the tests, measurements are taken several times and then an average value is calculated. The liquid, which is transparent in the ultrasound, also gave the examination the name of the nuchal translucency measurement. The terms NT measurement, nuchal fold measurement and nuchal translucency measurement are all used equivalently.
