Case of the Week #606

LaShell Jones, RDMS RDCS-FE
Maternal Fetal Associates in Reston, Virginia

Posting Dates: May 31, 2024 - Jun 14, 2024

40-year-old multipara with type II diabetes presents at 16 weeks for genetic scan because she missed her 1st trimester screening exam.  Ultrasound revealed the following findings. There were other numerous abnormalities in the rest of the scan apart from the ones shown here.

Image 1
Image 2
Image 3
Image 4
Image 5
Image 6
Image 7
Image 8
Image 9
Image 10

View the Answer Hide the Answer


We present a case of Trisomy 21. Non-invasive prenatal testing was concerning for Down's syndrome and amniocentesis confirmed the diagnosis.

Our images demonstrated the following:

  • Image 1: Absent Nasal Bone
  • Image 2: liver calcifications
  • Image 3-4: Echogenic bowel
  • Image 5: "Keyhole" Dandy Walker Variant
  • Image 6: Lagging Cerebellum measurement
  • Image 7: VSD
  • Image 8: Absent A - wave Ductus Venosus
  • Image 9: Pericardial Effusion
  • Image 10: Thick Nuchal Fold


Down Syndrome, also known as trisomy 21, is the most prevalent chromosomal abnormality observed in newborns. Approximately 6,000 infants are born with Down Syndrome annually in the United States, equating to a frequency of about 1 in every 700 births. Various prenatal genetic screening methods and diagnostic tests are utilized to accurately identify Down Syndrome and other aneuploidies during pregnancy.

Ultrasound plays a crucial role in the screening for aneuploidies. It enables the detection of both major structural abnormalities and minor soft markers in fetuses affected by aneuploidies. Down Syndrome can manifest with anomalies in various systems such as cardiovascular, central nervous, craniofacial, musculoskeletal, gastrointestinal, and urinary tract. Notably, major structural anomalies like duodenal atresia and cardiac defects such as septal defects, tetralogy of Fallot, and atrioventricular canal defects may not always be identified through prenatal ultrasound screening.

Nuchal translucency (NT) measurement in the first trimester is indicative of the subcutaneous fluid-filled space at the back of the fetal neck. An increased NT measurement is associated with a higher risk of aneuploidies, including Down Syndrome, with a detection rate ranging from 64% to 70%. Additionally, the presence of a nuchal cystic hygroma or a hypoplastic/absent nasal bone in the first trimester can also indicate a risk of aneuploidies, including Down Syndrome.

During the second trimester, soft markers such as echogenic intracardiac foci, pyelectasis, short femur length, choroid plexus cysts, echogenic bowel, thickened nuchal skin fold, and ventriculomegaly are commonly assessed. Some of these markers, like echogenic bowel, thickened nuchal fold, and ventriculomegaly, have high likelihood ratios, prompting further genetic counseling and additional screening or diagnostic tests. Conversely, markers with lower predictive values may also warrant aneuploidy screening if not previously conducted.

While ultrasound is a valuable tool in identifying potential markers for Down Syndrome, it should not be solely relied upon for diagnosis. Combining ultrasound findings with maternal serum screening tests, such as first and second trimester screening, as well as integrated and sequential screening, enhances the sensitivity for detecting Down Syndrome. Cell-free DNA testing boasts a high detection rate of 99% for Down Syndrome. Diagnostic procedures like amniocentesis or chorionic villus sampling should be considered when screening results indicate a positive likelihood of aneuploidies.


American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Obstetrics; Committee on Genetics; Society for Maternal-Fetal Medicine. Screening for Fetal Chromosomal Abnormalities: ACOG Practice Bulletin, Number 226. Obstet Gynecol. 2020 Oct;136(4):e48-e69.

Discussion Board

Start a discussion about this case


Dianna Heidinger Profile Pic

Dianna Heidinger United States Sonographer

Javier Cortejoso Profile Pic

Javier Cortejoso Spain Physician

Padmanaban Koochu Govindaraju Profile Pic

Padmanaban Koochu Govindaraju United Kingdom Sonographer

Igor Yarchuk Profile Pic

Igor Yarchuk United States Sonographer

Ana Ferrero Profile Pic

Ana Ferrero Spain Physician

Vladimir Lemaire Profile Pic

Vladimir Lemaire United States Physician

Tatiana Koipish Profile Pic

Tatiana Koipish Belarus Physician



Aysegul Ozel Profile Pic

Aysegul Ozel Turkey Physician


ALBANA CEREKJA Italy Physician

Deval Shah Profile Pic

Deval Shah India Physician

Murat Cagan Profile Pic

Murat Cagan Turkey Physician

Mesud Sehic Profile Pic

Mesud Sehic Bosnia and Herzegovina Physician

gholamreza azizi Profile Pic

gholamreza azizi Iran, Islamic Republic of Physician

Gayane Begjanyan Profile Pic

Gayane Begjanyan Armenia Physician

Ionut Valcea Profile Pic

Ionut Valcea Romania Physician

reyhan ayaz Profile Pic

reyhan ayaz Turkey Physician

Kathrine Montagne Profile Pic

Kathrine Montagne United States Sonographer

Zuzana Briešková Profile Pic

Zuzana Briešková Slovakia Physician


CHERYL TURNER United States Sonographer

Perrine Riou-Kerangal Profile Pic

Perrine Riou-Kerangal French Polynesia Sage-femme échographiste

Veronika Bartkovjaková Profile Pic

Veronika Bartkovjaková Slovakia Physician

Petra Barboríková Profile Pic

Petra Barboríková Slovakia Physician

Nguyễn Lê Hoàng Profile Pic

Nguyễn Lê Hoàng Viet Nam Physician

Denys Saitarly Profile Pic

Denys Saitarly Israel Physician

Le Tien Dung Profile Pic

Le Tien Dung Viet Nam Physician

Costin Radu Lucian Profile Pic

Costin Radu Lucian Romania Physician

Gaurav Sharma Profile Pic

Gaurav Sharma India Physician

Le Duc Profile Pic

Le Duc Viet Nam Physician

Erika Zanzarelli Profile Pic

Erika Zanzarelli Italy Physician

Aigerim Nukenova Profile Pic

Aigerim Nukenova Kazakhstan Physician

Rebekah Matherly Profile Pic

Rebekah Matherly United States Sonographer


PADMA Priya DHARSHINI India Radiologist

Hana Habanova Profile Pic

Hana Habanova Slovakia Physician

Anjali Gupta Profile Pic

Anjali Gupta India Physician

Mithun Chowdhury Profile Pic

Mithun Chowdhury Bangladesh Physician

ELHAM M Profile Pic

ELHAM M Saudi Arabia Physician



Syeda Amna Mehmood Profile Pic

Syeda Amna Mehmood United Arab Emirates Physician

Mirjam Moser Profile Pic

Mirjam Moser Switzerland Physician

Luan Nguyen Thanh Profile Pic

Luan Nguyen Thanh Viet Nam Physician

Quan Le Profile Pic

Quan Le Viet Nam Physician

Angel Barco Profile Pic

Angel Barco United Arab Emirates Sonographer

Add bookmark Bookmarked