Sonographic identification of second‐trimester fetuses with Down's syndrome

Fetal aberrant right subclavian artery in normal and Down syndrome fetuses

“…Vascular ‘signs’ for chromosomal abnormalities have recently been added to the list of ‘markers’ for chromosomal aberrations. Their non‐proven benefit, considerable false‐positive rate and often negative impact on the prospective parents' state of mind can reflect poorly on a professional's reliability and on the relationship between patient and healthcare provider1, 2.…”

Sonographic visualization of the middle phalanx of the fetal fifth digit between 13 and 17 weeks of gestation

“…Antenatal risk assessment of Down syndrome involves screening for a growing number of sonographic signs, or ‘soft markers’, which present more frequently in the Down syndrome fetal population. Their non‐proven benefit, considerable false‐positive rate and often negative impact on the prospective parents' state of mind can reflect poorly on a professional's reliability and on the relationship between patient and healthcare provider1–4.…”

“…The use of high‐resolution transvaginal probes in these services may result in the more frequent appearance of various sonographic ‘markers’ than when routine transabdominal anatomical screening between 19 and 23 weeks of gestation is performed. Included among these markers are: a shorter long‐bone length, cervical cysts, heterogeneous echogenicity of the choroid plexus, and the absence or hypoplasia of the middle phalanx of the fifth digit (MPFD)1, 5. Hypoplasia of MPFD as well as reduced ratio of the middle phalanges of the fifth to the fourth digits were described among the sonographic features in fetuses with Down syndrome.…”

“…Hypoplasia of MPFD as well as reduced ratio of the middle phalanges of the fifth to the fourth digits were described among the sonographic features in fetuses with Down syndrome. However, these studies were conducted in fetuses between 15 and 20 weeks of gestation and dealt with hypoplasia rather than absence of the middle phalanx1, 5, 6.…”

Advancing further the sonographic estimation of Down syndrome risk—how early can we go?

“…Subsequent to the identification of the nuchal fold as a marker for Down syndrome, other sonographic findings were identified as minor markers for an increased risk of Down syndrome. These include pyelectasis, an echogenic intracardiac focus, hyperechoic bowel, short humerus, and short femur7, 8, 10–12. The combination of these markers evolved into what is now known as the second‐trimester genetic sonogram.…”