Recognition of abnormal results when ultrasound of fetal nape translucion

The article was consulted professionally by Master, Dr Ta Quoc Tau – Obstetrics and Gynecology Department – Share99 Da Nang International Health Hub.

Nape opacity is a very familiar phrase for all mothers who have been pregnant, but not everyone fully understands its importance. During pregnancy, it is very important to perform a test to measure nape skin opacity.

1. The importance of measuring nape skin opacity

The time in which it is in place is required to carry out a measurement of nape skin opacity from the 11-13 weeks 6 days of pregnancy. If done outside this time period, the result will no longer be accurate.

The results of the skin opacity measurement will help the doctor diagnose the risk of fetuses with Down syndrome early to give the best advice and this is the basis for the doctor to decide whether the mother needs to perform some more pre-birth screening tests.

The higher the skin opacity of the nape, the higher the percentage of fetuses at risk of Down syndrome, and on the contrary, the lower the skin opacity of the nape, the lower the rate of fetuses at risk of Down syndrome.

The method of measuring nape skin opacity is up to 75% accurate, so there are still cases where the mother is concluded to be at high risk but the birth is still healthy, this rate falls around 1/20 or 1/25 of the mother.

2. How is the result of measuring nape skin opacity calculated?

Part of the risk of fetal malformations will be shown by the results of the measurement of nape skin opacity. If the skin opacity of the nape thickens, it may be associated with some malformations such as Down syndrome and some other structural abnormalities such as congenital heart disease, congenital diaphragm hernia …

For fetuses between 45mm and 84mm, the skin opacity of the nape is less than 3.5mm, the fetus is considered to be developing normally with a low incidence of malformations. As the skin opacity of the nape thickens, the incidence of Down's syndrome as well as other chromo symptom abnormalities will also increase.

Technique for measuring nape skin opacity:

  • Nape opacity: the negative drum image (fluid in essence) is located behind the nape of the neck, the upper limit can be exceeded on the nape towards the skull, the bottom extends to the back of the pregnancy. Physical presence at the 10th to 14th week
  • Take measurements from weeks 11 to 13 weeks 6 days
  • Butt head length: 45 mm <CRL < 84 mm
  • Make 3 measurements and get the largest measurement results
  • Vertical cross section exactly with saddle pregnancy
  • Magnification images
  • Distinguish the amniotic membrane from the tissue
  • Place the cursor in the right position

Recognition of abnormal results when ultrasound of fetal nape translucion

Recognition of abnormal results when ultrasound of fetal nape translucion

3. Recognition of abnormal results when ultrasound of fetal nape translucion

  • Previously selecting the 3mm threshold, the author chose 2.5 for all embryos from 11-13 weeks 6 days
  • NT will increase according to THE CRL, it is necessary to compare NT with CRL to recognize abnormal NT increases .
  • Called increase when NT > percentile 95th corresponds to CRL
  • The thicker the NT, the higher the frequency of NST abnormalities

Recognition of abnormal results when ultrasound of fetal nape translucion

The thicker the NT, the higher the frequency of NST abnormalities

There are some malformations that are only detected when the fetal ultrasound at the 20th week such as cleft palate, cracked spine … In some cases, the skin opacity of the nape is within the dangerous threshold but it is unlikely that the baby has Down's syndrome, or has a standard nape opacity but it is not yet possible to be sure that the baby was born without Down's, so you can perform more tests to get more accurate results.

The blurring of the nape of the neck helps the pregnant woman to detect early the risk of possible malformations in the fetus. The implementation of this test is essential and really important. However, pregnant mothers should not be too confused when the blurred skin of the nape of the neck has abnormal results, it is necessary to see a doctor for advice as well as a solution to avoid adverse effects on the health of themselves as well as the fetus.

Share99 International Health Hub offers a full maternity care program for women from the very beginning of pregnancy from the first months with a full range of pregnancy examinations, 3D ultrasounds, 4D routines and routine tests to ensure the mother is always healthy and the fetus develops comprehensively. Maternity will no longer be alone when entering labor because having a companion helps the process of childbirth always bring peace of mind and happiness.

Master. Dr Ta Quoc Original is a Lecturer in Obstetrics and Gynecology at Thai Nguyen University of Medicine and Pharmacy, Obstetrician and Gynecologist of Thai Nguyen Tw General Health Hub, Deputy Dean of Obstetrics and Gynecology Department of University of Medicine. The doctor has a full range of practice certificates in the field of obstetrics and gynecology such as ultrasound, laparoscopic surgery, endoscopy and cervical incul burning, artificial insefining (IUI) …

Experience and strengths in the fields of:

  • Obstetrics and Gynecology Ultrasound
  • Laparoscopic surgery in gynecology
  • Pre-production consulting
  • Examination and consultation of gynecology diseases
  • Rare examination and consultation, performing the technique of pumping sperm into the uterus chamber,
  • Pre-vaccination screening and post-vaccination response handling…

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About: Minh Quynh

b1ffdb54307529964874ff53a5c5de33?s=90&d=identicon&r=gI am the author of I had been working in Vinmec International General Hospital for over 10 years. I dedicate my passion on every post in this site.


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