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Abstracts the lungs, but also cause mediastinal shifting. We were surprised that a review of the literature on the subject showed that fetal heart shifting in CDH has not been assed objectively. In the present study data on objective cardiac deviation and the malposition in a group of 23 fetuses (18 survivors and five nonsurvivors) with isolated left sided CDH. The potentials of this parameter in predicting postnatal mortality and morbidity are discussed. 1123 Prenatal diagnosis of ventral wall defects Lee Y-H, Samsung Cheil Hospital, Sungkyunkwan University School of Medicine, Korea Ventral wall defects are a common group of fetal anomalies and a wide variety of ventral wall defects are diagnosed. And there are various options for perinatal management of fetal ventral wall defects, which range from termination of pregnancy to normal term delivery with postnatal surgery, depending on the type and severity of the lesion and probability of associated structural and chromosomal abnormalities. The routine fetal ultrasonography with widespread use of maternal serum alpha fetoprotein (AFP) screening allows the majority of ventral wall defects to be identified prenatally. But confusion arises when the ventral wall defect is complex or has other associated abnormalities. The accurate prenatal diagnosis of ventral wall defects is important because it affects patient management and prognosis. This lecture reviews the characteristic sonographic findings with possible pathological correlation, the associated structural and/or chromosomal abnormalities and outcome of simple and complicated types of ventral wall defects, which were diagnosed on our hospital over a 10-y period. 1124 Fetal thoracic anomalies Benson C, Harvard Medical School, Brigham and Women’s Hospital, United States of America Prenatal sonographic evaluation of the thorax begins with an evaluation of the supporting structures of the thorax. The size and shape of the thorax are evaluated to identify fetuses at risk for pulmonary hypoplasia as a result of a skeletal dysplasia or prolonged oligohydramnios. The next step in the evaluation of the fetal thorax is to determine if normal intrathoracic structures are present and in the proper location. Using this approach, anomalies such as unilateral pulmonary agenesis and situs inversus will be identified. Once the internal thoracic organs, the heart and lungs, have been identified, these structures are assessed for normalcy. In particular, the lungs are evaluated for abnormal masses and regions of abnormal echogenicity. During this evaluation, pulmonary anomalies, such as congenital cystic adenomatoid malformation and pulmonary sequestration, can be diagnosed. Congenital cystic adenomatoid malformation and pulmonary sequestration are among the spectrum of lesions included under the heading of pulmonary dysplasias. To distinguish among the different types of pulmonary dysplasias, lung masses should be evaluated for echogenicity and the size of the cysts, if present. In addition, it is important to determine the arterial blood supply to the lesion, i.e., systemic or pulmonary and the venous return, i.e., to the right atrium or to the left atrium. In addition to pulmonary masses, intrathoracic masses may be seen with intrathoracic teratomas and diaphragmatic hernias. These lesions are separate from the lung and compress normal lung tissue. Diaphragmatic hernias are defects, typically in the posterior diaphragm, which allow intraabdominal contents to herniate into the chest. They are more common on the left than right. Prognosis is related to the presence of other anomalies and to the degree of pulmonary hypoplasia that results from lung compression within the thorax. Pleural effusions may be seen in the fetus as an isolated findings or as a component of generalized hydrops.

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The cause of a pleural effusion should be sought with invasive procedures, such as amniocentesis or fetal thoracentesis, to determine if the etiology can be treated prenatally. 1125 First trimester prediction of congenital heart defect using NT and Doppler velocimetry Bahado-Singh RO, Wayne State University, United States of America Congenital heart defect is the most important group of birth defects with a frequency of ⱖ 8 to 10/1000 live births. Routine prenatal screening for CHD is still not the standard of care in the USA primarily due to the lack of simple and efficacious screening tools. The standardized measurement of first-trimester nuchal translucency for aneuploidy detection has kindled an interest in early fetal evaluation. One consequence has been the identification of a number of first-trimester sonographic markers, which appear to correlate with CHD. The first such marker is increased nuchal translucency. Initial postmortem studies revealed as association between increased first-trimester nuchal translucency and CHD in both anomalous and chromosomally normal fetuses. Subsequent studies have confirmed this association in chromosomally normal fetuses. A recent meta-analysis of published data consisting of a total of 162 such major CHD suggest that approximately 30% of such cases can be detected using an NT threshold of ⬎99% percentage for crown-rump length (false positive rate of 1%), which performs better than standard screening methods such as maternal diabetes. Further, nuchal translucency values are increased in the chromosomally abnormal fetus with CHD compared to their normal counterpart. This may be the consequence of the cumulative impact of different mechanisms that contribute to the development of increased nuchal fluid. Most studies of nuchal translucency and CHD have been performed in high risk populations. Two screening studies in the USA have confirmed the exponential increase in the risk of CHD with increasing first trimester NT measurement. The next sonographic finding marker used in the first trimester for CHD detection is the ductus venosus Doppler. Ductus venosus velocimetry provides information on the right intraatrial pressure and directly right ventricular pressure. As such it is believed by some that abnormal ductus venosus profiles in CHD may be due to impaired atrial contraction, reduced myocardial compliance and ultimately cardiac decompensation. Similar ductus venosus Doppler changes can however occur in first trimester cases with increased nuchal translucency with and without karyotype abnormalities even in the absence of CHD. This suggests that other mechanisms are involved in the Doppler changes. High risk population studies suggest a 65% sensitivity for CHD with a false positive rate of 21% in a chromosomally normal group. Finally, preliminary data is emerging on tricuspid regurgitation as a marker of first trimester cardiac defects. Limited preliminary data indicate that 50% of trisomy 21 fetuses with no CHD will have evidence of tricuspid regurgitation. In chromosomally normal first-trimester cases with CHD slightly less than 50% have been found to have tricuspid regurgitation for a false positive rate of 5.6%. Among Trisomy 21 cases with CHD, the same study found a 97.5% rate of tricuspid regurgitation. Nuchal translucency measurements may have moderate utility for CHD screening in the general population. The value of the other two markers for low risk screening is much less certain.

FETAL INFECTION AND OTHERS 1126 Ultrasound markers of fetal infections Bailao LA, Diagnosis-Ultrasound Medical Diagnosis Center, Brazil The evidences of fetal infection may be as subtle as nascent intrauterine growth restriction (IUGR), mildly inappropriate calcification of fetal