ultrasound diagnosis of fatal anomalies

14 Placenta, Cord, and Amniotic
Fluid
Chorioangioma
Definition: Benign vascular tumors of the
placenta, usually single, encapsulated and
round-shaped tumors situated within the
placenta.
Incidence: This is the most frequent placenta
tumor, detected histologically in 1% of all
placentas.
Clinical history/genetics: Sporadic occurrence.
Ultrasound findings: The fetus usually shows
normal development. Rarely, fetal hydrops may
result secondary to arteriovenous shunting
within the tumor, which causes increased
volume overload to the fetal heart. The earliest
signs are hepatosplenomegaly and pericardial
effusion. Pleural effusion, ascites, and skin
edema may also result. Hydramnios is
frequently present. Subsequent fetal anemia
often leads to growth restriction. Chorioangioma
can be detected as a vascular tumor within the
placenta, located mostly near the insertion of the
umbilical cord, and protruding into the amniotic
cavity. Chorioangiomas causing hemodynamic
complications are usually larger than 6 cm. They
may even develop in the later stages of pregnancy.
Clinical management: Regular scans are recommended
to detect the development of fetal hydrops
and growth restriction as early as possible.
Chorioangioma may even regress spontaneously
during the course of pregnancy. The resulting
hydramnios may lead to premature labor and
delivery.
Procedure after birth: Unexpected neonatal
anemia may be due to chorioangioma.
Prognosis: Most chorioangiomas do not have
any pathophysiological relevance. Very rarely,
vessel anastomosis within the tumor overload
the fetal heart, causing fetal hydrops.
References
Bashiri A, Maymon E, Wiznitzer A, Maor E, Mazor M.
Chorioangioma of the placenta in association with
early severe polyhydramnios and elevated maternal
serum HCG: a case report. Eur J Obstet Gynecol Reprod
Biol 1998; 79: 103–5.
Fig. 14.1 Chorioangioma. A large chorioangioma
on the surface of placenta at 30 weeks’ gestation.
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