Second-Trimester Sonography and Trisomy 18

Abstract

Objective. To estimate the risk of trisomy 18 with the finding of isolated choroid plexus cysts after a standard sonographic examination that is extended to include the fetal hands. Methods. A retrospective chart review was performed on all fetuses with choroid plexus cysts on second-trimester sonographic examinations. When choroid plexus cysts were identified, our standard protocol for fetal evaluation was expanded to include the hands. If no other findings were noted on completion of this examination, the choroid plexus cysts were classified as "isolated." These results were correlated with the presence or absence of trisomy 18 to determine the impact of this approach for the detection of fetuses with this aneuploidy. Results. From March 1990 to the end of 2001, 49,435 fetuses that were subsequently delivered at our hospital were scanned between 16 and 25 menstrual weeks. At least 1 choroid plexus cyst was detected in 1209 fetuses (2.3%), of which 1060 were isolated. No fetuses with isolated choroid plexus cysts had trisomy 18. However, 3 fetuses with trisomy 18 had choroid plexus cysts and abnormal hands as their only abnormal findings. Conclusions. Fetuses with an apparently isolated finding of choroid plexus cysts can be further evaluated by extending the standard examination to include the hands. If no other findings are identified, the risk of trisomy 18 appears to be low. Key words: antenatal sonography; choroid plexus cysts; trisomy 18. n 1984, Chudleigh et al 1 published the initial report on the prenatal detection of choroid plexus cysts by prenatal sonography. At that time, it was thought to be a finding without pathologic significance. Two years later, the association of choroid plexus cysts with trisomy 18 was first suggested. Received July 8, 2003, from the Division of Fetal Imaging, Department of Obstetrics and Gynecology (R.B., W.L., I.M.V., C.H.C.), and Division of Biostatistics (R.H.), William Beaumont2 Subsequent studies indicated that choroid plexus cysts are a common finding with trisomy 18. They are seen in up to half of second-trimester fetuses and are often found with other anomalies. [3][4][5][6][7][8][9][10][11][12][13] In the nearly 2 decades since the initial report by Chudleigh et al, 1 a large volume of literature has been published regarding the sonographic detection of choroid plexus cysts in the second trimester. Despite this, a consensus of opinion has yet to be reached on the genetic significance and appropriate management when

Clinical characteristics and survival of trisomy 18 in a medical center in Taipei, 1988–2004

“…Our study showed 32% of trisomy 18 cases had cerebellar hypoplasia by brain ultrasonography. By the prenatal sonography, Bronsteen et al [2004] and Sahinoglu et al [2004] both found that larger choroid plexus cysts were associated with trisomy 18. Our study revealed that 19% of our cases showed choroid plexus cysts.…”

Prevalência das malformações congênitas identificadas em fetos com trissomia dos cromossomos 13, 18 e 21

“…As malformações das extremidades inferiores e dos pés já foram encontradas em quase dois terços dos fetos com trissomia 18 19 . No geral, as malformações mais comumente descritas em fetos com trissomia do cromossomo 18 envolvem cérebro, coração e membros 20 . Em decorrência destas malformações, é bastante comum o achado de crescimento intrauterino restrito 13 .…”

Intrauterine death in singleton pregnancies with trisomy 21, 18, 13 and monosomy X

“…In the medical literature, the frequency of structural abnormalities in fetuses with T13/18 is high, and is found in 80 to 100%. 26,32,47,[54][55][56] In this study, of the 9 fetuses with prenatal diagnosis of T13/18 that showed no MF at the time of the karyotype studies, 6 underwent karyotype studies using CVS in the first trimester, showing an increased NT as an indication.…”