ultrasound diagnosis of fatal anomalies

ABDOMEN
Omphalocele
Definition: Omphalocele is a median anterior
wall defect characterized by the herniation of
intra-abdominal contents into the base of the
umbilical cord; in contrast to gastroschisis, the
defect is covered by a transparent membrane
(amnion and peritoneum). This membrane may
be absent if the omphalocele is ruptured in the
early stage. In umbilical hernia, on the other
hand, the hernial sac is covered completely with
skin.
Incidence: One in 4000 births.
Sex ratio: Contradictory reports, ranging from
M:F=1.6:1toM:F=1:5.
Clinical history/genetics: Mostly sporadic. Multifactorial
inheritance; recurrence rate in isolated
case of omphalocele in the sibling 1%.
Rarely inherited as autosomal-dominant or X-
chromosome recessive forms. In connection
with Beckwith–Wiedemann syndrome (omphalocele
or umbilical hernia, macroglossia,
acromegaly), autosomal-dominant inheritance
is possible, with variable expression.
Fig. 6.14 Omphalocele. Physiological omphalocele
at 10 weeks of gestation. Spontaneous remission.
Birth of a healthy neonate at term.
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Fig. 6.15 Omphalocele. Non-physiological omphalocele
at 12+4weeks.Thefetalvessels are
depicted using color Doppler energy, showing the
umbilical vessels at the caudal pole of the omphalocele.
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