Journal of Ultrasound in Medicine, Vol 15, Issue 5 389-394, Copyright © 1996 by American Institute of Ultrasound in Medicine
Isolated fetal choroid plexus cysts and karyotype analysis: is it necessary?
L. E. Shields, S. B. Uhrich, T. R. Easterling, D. R. Cyr and L. A. Mack
Department of Obstetrics and Gynecology University of Washington School of Medicine, Seattle, USA.
The purpose of this study was to evaluate the risk of fetal aneuploidy in
the presence of isolated choroid plexus cysts and to evaluate the results
obtained from our institution and those reported previously in the English
literature. All patients with fetal choroid plexus cysts on prenatal
ultrasonography were offered genetic counseling and amniocentesis for fetal
karyotyping. Seven of 274 fetuses, 2.6% (95% confidence interval = 1.0 to
5.2%), with isolated choroid plexus cysts were aneuploid. Literature
analysis located 23 other reports of 1537 fetuses with isolated choroid
plexus cysts; 26 were karyotypically abnormal, 1.7% (95% confidence
interval = 1.0 to 2.4%). When evaluating only those patients whose
indication for amniocentesis was choroid plexus cysts (i.e., eliminating
those patients with advanced maternal age or abnormal serum screening) the
risk of having a fetus with trisomy 18 changed little, 1.9% (95% confidence
interval = 0.4 to 5.5%). Our data, combined with those of the literature,
suggest that the risk of finding an abnormal fetal karyotype in the
presence of isolated choroid plexus cysts is at least 1% and may be as high
as 2.4%. On the basis of these results, genetic counseling and prenatal
diagnosis should be offered to these patients.
