This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Cafici, D. Articles by Sepulveda, W. Search for Related Content PubMed PubMed Citation Articles by Cafici, D. Articles by Sepulveda, W.

First-Trimester Echogenic Amniotic Fluid in the Acrania-Anencephaly Sequence

Ultrasound and Prenatal Diagnosis Unit, Ecodiagnostico Alem, Buenos Aires, Argentina (D.C.); and Fetal Medicine Center, Department of Obstetrics and Gynecology, Clinica Las Condes, Santiago, Chile (W.S.).

Address correspondence and reprint requests to Waldo Sepulveda, MD, Centre for Fetal Care, Queen Charlotte’s and Chelsea Hospital, Hammersmith Hospitals National Health Service Trust, Du Cane Road, London W12 0HS, England. E-mail waldosep{at}hotmail.com.

Objective. To describe the association between echogenic amniotic fluid and first-trimester fetal acrania. Methods. Nine fetuses with acrania were examined between 11 weeks’ and 13 weeks 6 days’ menstrual age for the presence of echogenic free-floating particles in the amniotic fluid. Cases were classified into 3 types according to the echogenicity of the amniotic fluid: similar to (type 0), slightly greater than (type 1), and clearly more echogenic than (type 2) that of the extracelomic fluid. Results. In 1 pregnancy, no free-floating particles were identified (type 0). In 6 cases, small free-floating particles scattered within the amniotic cavity were identified, making the amniotic fluid slightly more echogenic than the extracelomic fluid (type 1). In the remaining 2 cases, the amniotic fluid was homogeneously and clearly more echogenic than the extracelomic fluid (type 2). Conclusions. A high percentage (89%) of fetuses with acrania had echogenic amniotic fluid, suggesting that this finding could potentially be used as a marker of fetal acrania in the first trimester. This finding also supports the hypothesis of the transition from acrania to anencephaly, with the unprotected brain undergoing progressive destruction from the first trimester, leading to the classic finding of anencephaly in the second trimester.

Key Words: acrania • anencephaly • fetal sonography • first trimester • prenatal diagnosis