Nuchal scan nhsmail
The nuchal scan!
The nuchal scan, also known as the nuchal translucency (NT) scan, is a routine ultrasound examination performed during pregnancy to assess the risk of certain chromosomal abnormalities, particularly Down syndrome (trisomy 21).
Here's what you need to know:
What is a nuchal scan?
A nuchal scan is a non-invasive ultrasound examination that measures the thickness of the nuchal translucency (NT) - the clear space at the back of the fetal neck. The scan is usually performed between 11 and 14 weeks of gestation.
Why is a nuchal scan performed?
The nuchal scan is performed to:
- Assess the risk of Down syndrome: The NT measurement is used to calculate the risk of Down syndrome, which is a chromosomal abnormality that can cause intellectual disability, heart defects, and other health problems.
- Identify other chromosomal abnormalities: The scan can also detect other chromosomal abnormalities, such as trisomy 13 and trisomy 18.
- Monitor fetal development: The scan provides an opportunity to check the overall fetal development, including the heart, brain, and other organs.
How is a nuchal scan performed?
The scan is usually performed by a sonographer or a radiologist using a transabdominal ultrasound machine. The procedure typically takes around 10-15 minutes. Here's what you can expect:
- Positioning: You'll be asked to lie on your back with your abdomen exposed.
- Gel application: A small amount of gel will be applied to your abdomen to help the ultrasound probe transmit and receive sound waves.
- Probe placement: The sonographer will place the probe on your abdomen to capture images of the fetus.
- NT measurement: The sonographer will measure the thickness of the nuchal translucency (NT) in millimeters.
- Fetal assessment: The sonographer will also assess the fetal development, including the heart, brain, and other organs.
What are the results of a nuchal scan?
The results of a nuchal scan are usually reported as a risk score, which is calculated based on the NT measurement and other factors, such as the mother's age and the presence of other risk factors. The risk score is usually expressed as a percentage, indicating the likelihood of the fetus having a chromosomal abnormality.
What are the risks associated with a nuchal scan?
The risks associated with a nuchal scan are generally very low. However, there are some potential risks to consider:
- False positive results: A false positive result can lead to unnecessary anxiety and further testing.
- False negative results: A false negative result can lead to a delay in diagnosis and treatment.
- Fetal movement restriction: The scan may cause temporary restriction of fetal movement.
Conclusion
The nuchal scan is a valuable tool in prenatal care, providing valuable information about the risk of chromosomal abnormalities and allowing for early detection and intervention. While there are some potential risks associated with the scan, the benefits generally outweigh the risks. If you have any concerns or questions, be sure to discuss them with your healthcare provider.