ultrasound diagnosis of fatal anomalies

ECHOGENIC BOWEL
Echogenic Bowel
Definition: Increased echogenicity of the bowel
in the second trimester, such that it is equal to
that of surrounding fetal bone. The most
frequent cause is intra-amniotic bleeding. The
echogenicity is a soft marker for chromosomal
anomaly, especially for Down syndrome. In the
third trimester, bowel containing echogenic meconium
is a normal finding.
Incidence: 0.6% of all fetuses in the second
trimester.
Ultrasound findings: Loops of the bowel show a
strong echogenic content. Weak echo can be excluded
by reducing the overall density of the ultrasound
picture. At the lowest level of reduction,
only the bones and the echogenic bowel can
be demonstrated if their echogenicity is similar.
Differential diagnosis: The differential diagnosis
in these findings can be clarified from the study
by Yaron et al., who investigated 79 cases of
echogenic bowel. No cause was found in 30 cases
(38%); intra-amniotic bleeding was the cause in
19% (n = 15); other anomalies were associated in
Fig. 10.3 Echogenic bowel. The scan shows echogenic
bowel as well as ascites and hygroma colli in a
fetus with trisomy 21.
Fig. 10.4 Echogenic bowel. Longitudinal section of
a male fetus (arrow: penis) at 12 +2 weeks.
3
221