ultrasound diagnosis of fatal anomalies

AQUEDUCT STENOSIS
has a “frog-like” appearance, with prominent orbits.
Myelomeningocele in the cervical or lumbosacral
region may accompany this anomaly. In
late pregnancy, the absence of a swallowing reflex
leads to hydramnios.
Clinical management: After the diagnosis is
made, most women opt for termination of pregnancy.
In the remaining cases, treatment for hydramnios
is indicated to relieve maternal symptoms.
Procedure after birth: Therapy is not possible.
Some of the affected neonates survive as much
as a few days after birth.
Prognosis: This is considered to be a fatal malformation,
resulting in intrauterine death in 50%
of the affected fetuses, with the remaining 50%
dying at the neonatal stage.
Recommendation for the patient: Before planning
the next pregnancy, a regular daily intake of
folic acid (4 mg/d) considerably reduces the risk
of recurrence.
Self-Help Organization
Title: Anencephaly Support Foundation
Description: Provides support for parents
who are continuing a pregnancy after being
diagnosed with an anencephalic infant. Information
and resources for parents and professionals.
Phone support, pen pals, literature,
pictures.
Scope: International network
Aqueduct Stenosis
Definition: Displacement or congenital malformation
of the aqueduct of Sylvius resulting in a
congenital obstructive hydrocephalus.
Incidence: One in 2000 births.
Sex ratio: M:F=1.8:1
Clinical history/genetics: Most cases are
sporadic; 2–5% of hydrocephalus cases unrelated
to a neural tube defect are inherited recessively
through an X-chromosome-linked gene.
Founded: 1992
Address: 20311 Sienna Pines Court, Spring,
TX 77379, United States
Telephone: 1–888–206–7526
E-mail: asf@asfhelp.com
Web: http://www.asfhelp.com
References
Anon. Prevalence of neural tube defects in 20 regions of
Europe and the impact of prenatal diagnosis, 1980–
1986. EUROCAT Working Group. J Epidemiol Community
Health 1991; 45: 52–8.
Becker R, Mende B, Stiemer B, Entezami M. Sonographic
markers of exencephaly–anencephaly sequence at
9 + 3 gestational weeks. Ultrasound Obstet Gynecol
2000; 16: 582–4.
Boyd PA, Wellesley DG, De Walle HE, et al. Evaluation of
the prenatal diagnosis of neural tube defects by fetal
ultrasonographic examination in different centres
across Europe. J Med Screen 2000; 7: 169–74.
Cuiller F. [Prenatal diagnosis of exencephaly at
10 weeks’ gestation, confirmed at 13 weeks gestation;
in French.] J Gynecol Obstet Biol Reprod (Paris)
2001; 30: 706–7.
Drugan A, Weissman A, Evans MI. Screening for neural
tube defects. Clin Perinatol 2001; 28: 279–87.
Goldstein RB, Filly RA, Callen PW. Sonography of anencephaly:
pitfalls in early diagnosis. JCU J Clin Ultrasound
1989; 17: 397–402.
Hardt W, Entezami M, Vogel M, Becker R. Die fetale Exenzephalie—Vorstadium
der Anenzephalie? Ein kasuistischer
Beitrag. Geburtshilfe Frauenheilkd 1999;
59: 135–8.
Wilkins HL, Freedman W. Progression of exencephaly to
anencephaly in the human fetus: an ultrasound perspective.
Prenat Diagn 1991; 11: 227–33.
Worthen NJ, Lawrence D, Bustillo M. Amniotic band
syndrome: antepartum ultrasonic diagnosis of discordant
anencephaly. JCU J Clin Ultrasound 1980; 8:
453–455.
The cause seems to be mutations of the L1 CAM
gene (gene locus Xq28).
Teratogens: Congenital infections (cytomegalovirus,
rubella, toxoplasmosis).
Embryology: The sylvian aqueduct connects the
third and fourth ventricles and develops in the
6th week after conception. In 50% of cases, local
infection such as gliosis can be detected histologically.
Associated malformations: In X-linked aqueduct
stenosis, 20% of the affected boys show de-
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