There are limited interventions available for the management of large, symptomatic placental chorioangiomas. Although they can be treated with endoscopic laser coagulation of the feeding vessels, fetal bleeding, exsanguination, and death are potential complications of the procedure; therefore, this technique should be used with caution. The role of this treatment modality in the early devascularization of placental chorioangiomas prior to the development of significant complications warrants consideration.

Objective. To study the value of choroid plexus dysmorphology as a screening tool for the firsttrimester sonographic diagnosis of holoprosencephaly in a high-risk population. Methods. A total of 378 consecutive pregnancies undergoing chorionic villus sampling between 11 and 14 weeks' gestation were scanned before the procedure, following the recommendations of the Fetal Medicine Foundation (London, England). A cross-sectional view of the fetal brain, including the visualization of both choroid plexuses (the "butterfly" sign), was obtained in all cases. Results. There were 3 cases in which the butterfly sign was not identified. In these cases, the first-trimester diagnosis of holoprosencephaly was confirmed by the presence of a single monoventricular cavity and fused thalami. Two of these fetuses had features of facial dysmorphism at the time of presentation and 2 had extracranial anomalies, including a cystic hygroma in 1 and a small omphalocele and polydactyly in another. Chromosomal analysis showed trisomy 13 in 2 cases and a ring chromosome 13 in the other. Conclusions. This series suggests that failure to identify the butterfly sign is a warning sign of holoprosencephaly in the first trimester. Systematic identification of the butterfly sign at the time of sonographic assessment of nuchal translucency provides a valuable tool for the early screening of holoprosencephaly. Key words: brain anomalies; choroid plexus; first trimester; holoprosencephaly; prenatal sonography. MD, Fetal Medicine Center, Clinica Las Condes, Casilla 208, Santiago 20, Chile. E-mail waldosep@hotmail.com. Abbreviations CVS, chorionic villus samplingoloprosencephaly is a severe brain anomaly characterized by different degrees of fusion of the lateral ventricles resulting from failure of the prosencephalon to cleave during early embryogenesis. 1 This condition is invariably associated with a wide range of midfacial defects ranging from a single incisor to cyclopia. 2 Prenatal diagnosis of holoprosencephaly is usually made in the second trimester by the sonographic demonstration of fused lateral ventricles, no visible midline structures, and fusion of the thalami. 3 Recently, first-trimester sonographic screening for chromosomal abnormalities by measuring the nuchal translucency thickness at 11 to 14 weeks' gestation 4,5 has been increasingly incorporated into routine clinical practice. An important advantage of this examination is the possibility of an early examination of the fetal anatomy for major structural defects. [4][5][6]

Objective To determine the number of ultrasound examinations necessary for training sonographers to examine accurately the fetal nasal bone at 11-14 weeks' gestation. Methods

Objective In red blood cell (RBC) isoimmunized pregnancies fetal anemia is associated with a hyperdynamic circulation. The aim of the present study was to examine further the possible value of fetal middle cerebral artery peak systolic velocity (MCA-PSV)