Choroid Plexus Cysts
What is a Choroid Plexus Cyst?
The choroid plexuses are structures of the brain that make the cerebrospinal fluid,
the fluid that normally flows around the brain and spine.
Sometimes fluid becomes trapped and forms pockets in the choroid
plexus. If these pockets are larger than 2 millimeters they are called choroid plexus
A choroid plexus cyst is not a birth defect, and does not cause any long
term health problems or affect development of the baby’s brain .
How Common Are Choroid Plexus Cysts?
Choroid plexus cysts are seen
during 1% to 3% of all second trimester ultrasound examinations.
Choroid plexus cysts are seen at the same rate in fetuses with Down
syndrome. However, choroid plexus cysts are seen
much more frequently (about 40%) in fetuses with a condition called Edwards syndrome (also
known as trisomy 18) .
What is Edwards Syndrome?
Edwards syndrome, or Trisomy 18
is a rare disorder that happens when the baby has three copies of
chromosome 18 instead of the usual 2 copies. Chromosomes are the
structures in the cells of your body that are inherited from each of your
parents. Chromosomes hold
the instructions for how your body looks and functions.
Babies with trisomy 18 have
severe mental retardation and usually have many birth defects, because
of the extra chromosome 18. Only 5% to 10 % of infants survive the first year
after delivery. Death is usually caused by inability to maintain normal
breathing or heart and lung problems
How Can I Tell if My Baby Has Edwards Syndrome (trisomy
that are often seen in babies with
trisomy 18 include cleft lip and palate,
jaw, low set ears, club feet, clenched fists, a single umbilical artery , kidney abnormalities,
poor growth, and a high level of amniotic fluid (polyhydramnios) . More
than 90% of babies with
trisomy 18 will have a heart defect.
If the only finding is a choroid plexus cyst (or
cysts) on the ultrasound
examination, you are less than 35 years of age, and you have a normal
serum screening (quad screen) test, then the chances the baby has
trisomy 18 would be very low.
Amniocentesis may be offered
to you to count and examine the chromosomes of the baby.
Amniocentesis is a test in which a fine needle is inserted into the
uterus , and a sample of the fluid
that surrounds the baby is removed to obtain the baby's cells that
are present the fluid. The chances of amniocentesis causing loss
of the pregnancy (a miscarriage) due to breaking of your water bag or
causing premature labor is about 1 in 300.
What Happens To The Choroid Plexus Cysts?
Choroid plexus cysts generally go away by 28 weeks
Choroid Plexus Cyst Web Site
A place for expecting parents to exchange information and experiences about
choroid plexus cysts in their fetuses
1. Peleg D and Yankowitz J. Choroid plexus cysts and aneuploidy.J Med Genet.
2. Guariglia L, Rosati P. Prevalence and significance of isolated fetal
choroid plexus cysts detected in early pregnancy by transvaginal sonography
in women of advanced maternal age. Prenat Diagn. 1999;:128-131.
3. Shuangshoti S, Netsky MG. Histogenesis of choroid plexus in man.Am J Anat. 1966;118:283-316.
4. Chitkara U Choroid plexus cysts in the fetus: a benign anatomic variant
or pathologic entity? Report of 41 cases and review of the literature.
Obstet Gynecol. 1988;72:185-9.
Digiovanni LM, Choroid plexus cysts: infant and early childhood
Obstet Gynecol. 1997;90:191-4.
Burrows A Choroid plexus cysts in the fetal brain.
Aust N Z J Obstet Gynaecol. 1993 ;33:262-4.
Bromley B, Choroid plexus cysts: not associated with Down syndrome.Ultrasound Obstet Gynecol. 1996;8:232-5.
Yoder PR The second-trimester fetus with isolated choroid plexus cysts: a
meta-analysis of risk of trisomies 18 and 21.Obstet Gynecol. 1999;93:869-72.PMID:10912435
ACOG Practice Bulletin. Clinical Management Guidelines for
Obstetrician-Gynecologists. Prenatal diagnosis of fetal chromosomal
abnormalities.Obstet Gynecol. 2001;97(5 Pt 1):suppl 1-12.
Trisomy 18 Syndrome. In: Jones, Kenneth Lyons, M.D. Smith's Recognizable Patterns of Human Malformations, Saunders Co: Philadelphia, 1997: 14-15.
11. Coco C, Jeanty P. Karyotyping of fetuses with isolated choroid plexus
cysts is not justified in an unselected population. J Ultrasound Med. 2004
12. Ouzounian JG, et. al., Isolated choroid plexus cyst or echogenic cardiac
focus on prenatal ultrasound: is genetic amniocentesis indicated? Am J
Obstet Gynecol. 2007 Jun;196(6):595.e1-3; discussion 595.e3.
13. Nyberg DA, Souter VL.Sonographic markers of fetal trisomies: second
trimester.J Ultrasound Med. 2001 Jun;20(6):655-74.
14. Cereda A, Carey JC.The trisomy 18 syndrome.Orphanet J Rare Dis. 2012 Oct
23;7:81. doi: 10.1186/1750-1172-7-81.
15.Coco C, Jeanty P.Karyotyping of fetuses with isolated choroid plexus cysts is
not justified in an unselected population.
J Ultrasound Med. 2004 Jul;23(7):899-906.PMID:15292557
Ouzounian JG, et al., Isolated choroid plexus cyst or echogenic cardiac focus on prenatal
ultrasound: is genetic amniocentesis indicated? Am J Obstet Gynecol. 2007
Dagklis T, et. al., Choroid plexus cyst, intracardiac echogenic focus, hyperechogenic bowel and
hydronephrosis in screening for trisomy 21 at 11 + 0 to 13 + 6 weeks.
Ultrasound Obstet Gynecol. 2008 Feb;31(2):132-5.
Reviewed By Mark Curran MD, FACOG