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Recently published excitation functions in proton-proton ( pp) elastic scattering observables in the laboratory energy range 0.5-2.5GeV provide an excellent data base to establish firm upper limits on the elasticities ηel = Γel/Γtot of possible isovector resonant contributions to the nucleon-nucleon ( NN) system. Such contributions have been predicted to arise from dibaryonic states, with c.m. masses between 2.1-2.9GeV/c2, but have not been confirmed experimentally. A method to determine quantitatively the maximum value of ηel compatible with experimental data is presented. We use energy-dependent phase shift fits to the pp data base to model the non-resonant interaction. Based upon the differential cross-section data measured by the EDDA Collaboration an unbiased statistical test is constructed to obtain upper limits on ηel, that exclude larger values with a 99% confidence level. Results in the c.m. mass range 2.05-2.85GeV/c2 and total widths of 10-100MeV/c2 in the partial waves 1 S 0, 1 D 2, 3 P 0, 3 P 1, and 3 F 3 are presented and discussed. [ABSTRACT FROM AUTHOR]

Objectives Intra-uterine bowel perforation can occur secondary to a variety of abnormalities and cause sterile peritonitis in the fetus (generalised = type I). If sealing of the perforation does not take place, a thick-walled pseudo-cyst can form (type II). Methods Over a 12-year period, 21 616 pregnancies were screened for gastro-intestinal malformations using prenatal ultrasound. We identified 1077 cases suspicious of surgically correctable malformations. Post-natal diagnoses and outcome were worked up retrospectively. Result We found 96 fetuses with suspected gastro-intestinal malformations. Prenatal bowel perforation with meconium peritonitis was confirmed in 11 cases. In 5 of these 11, the correct diagnosis had been predicted prenatally. One child presented as a fetal and neonatal emergency (case report). Ten of the eleven infants were operated on during their first day of life. Intra-operative findings were atresia ( n = 4), meconium ileus ( n = 6) and no obvious cause ( n = 1). Two children suffered fatal complications. Conclusion Meconium peritonitis and meconium pseudo-cysts as its special manifestation are assessable by prenatal diagnosis but present in different ways. They can present as fetal ascites or echogenic bowel and cause fetal or neonatal distress, requiring close observation and highly specialised care. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We report on two cases of the prenatal diagnosis of arterio-venous communication between the intra-abdominal umbilical vein and atypical arteries. The diagnosis was made by color and spectral Doppler and ‘color power angiography’. Both cases presented with hydrops fetalis, one at 14 and the other at 31 weeks of gestation. In the first case, color Doppler demonstrated an atypical arterial vessel connecting the umbilical vein with the aorta; the ductus venosus was patent. Echocardiography showed a so-called atrioventricular canal. In the second case, a complex intrahepatic vascular malformation was found. Color Doppler demonstrated communications between the umbilical vein and the hepatic artery and an atypical artery; the ductus venosus was patent. In the latter case polyhydramnios, duodenal atresia and macroglossia were additionally detected. In both cases, fetal karyotyping revealed trisomy 21. The first case resulted in a missed abortion, the second in a stillbirth. All findings were confirmed on autopsy. Of interest is that both fetuses were affected with trisomy 21. The increasing use of color Doppler in prenatal diagnosis, especially in hemodynamically compromised fetuses, will help to determine the actual incidence of complex vascular malformations of the umbilical vein and to elucidate the impact of such malformations on fetal outcome. [ABSTRACT FROM AUTHOR]

The prenatal diagnosis of an aneurysm of the vein of Galen has been reported on only a few occasions. This rare arterio-venous fistula is suspected when an intracerebral hypoechoic cyst is found in which blood flow can be demonstrated by Doppler ultrasound. This is one of the few conditions where Doppler ultrasound is critical for the diagnosis. Three-dimensional color power Doppler (3D-CPA) is a recent ultrasound modality which enables the three-dimensional visualization of vessels and which is more readily available than magnetic resonance imaging (MRI) We report a fetus in which an aneurysm of the vein of Galen was detected at 33 weeks' gestation and where the application of 3D-CPA enabled a better understanding of the spatial orientation and course of the dilated vessels. The neonate was successfully treated with coil angiography but subsequently died at 5 months of age from cardiac decompensation. Where fetal malformations involve the vascular system, 3D-CPA appears to be a promising technique. [ABSTRACT FROM AUTHOR]

The determination of Chlamydia antibodies in serum is unsuitable for diagnosing infertility in men. The determination of secretory IgA in seminal plasma would seem to be of greater relevance. Since antibodies against C. trachomalis and C. pneumoniae can he detected, a species-specific test for the diagnosis of inkctions of the male genital tract should he used. Only at relatively high titers (≥1:400) do genus-specific tests agree with the species-specific micro-immunofluorescence test. Whether such values can be taken as a true indicator of a local, chronic infection remains to be investigated. [ABSTRACT FROM AUTHOR]

A case of twin reversed arterial perfusion (TRAP) sequence was diagnosed at 12 weeks' gestation using transvaginal color Doppler ultrasound, which demonstrated the presence of retrograde perfusion in the umbilical artery of the abnormal twin. Ultrasound imaging showed a monochorionic-diamniotic twin pregnancy with an inappropriately grown second twin, the morphological evaluation of which revealed an abnormal cephalic pole with acrania, diffuse subcutaneous edema and the presence of cardiac activity in an abnormal heart with a single chamber. [ABSTRACT FROM AUTHOR]

Objective The purpose of this investigation was to examine the characteristics of breathing-related fluid flow in the trachea of human fetuses with congenital diaphragmatic hernia in the hopes of developing a standard for the prenatal diagnosis of the degree of severity of the resulting pulmonary hypoplasia. Our ultimate goal is the prediction of postnatal mortality in fetuses with congenital diaphragmatic hernia. Subjects and methods The study comprised six cases of isolated congenital diaphragmatic hernia (one on the right side; five on the left) varying in gestational age from 26 to 36 weeks. Four of the patients survived after surgical repair and two died during the neonatal period owing to lung hypoplasia. Color Doppler was used to visualize the fluid displacement in the trachea generated by fetal breathing movements. Spectral Doppler was then used to analyze the fluid flow velocity waveforms. More than 40 continuous breathing cycles (inspiration + expiration) were recorded for each case. We distinguished between regular and irregular patterns. Results Only the regular breathing phases, defined as five or more consecutive cycles of symmetric appearance, were considered for analysis. The inspiration and expiration times, the peak velocity of inspired and expired fluid and the volume obtained by integration of the tracheal fluid flow displaced during fetal breathing were compared with those of five healthy fetuses for each gestational age. Only the tracheal volume flow was helpful in predicting outcome. In normal pregnancies this parameter increased from 0.21 ± 0.10 ml/breath (mean ± SD) at 26 weeks to 1.37 ± 0.48 ml/breath at 36 weeks of gestation. A significantly low (p < 0.05) volume flow was found only in the fetuses with congenital diaphragmatic hernia with a lethal postnatal outcome, whereas this parameter was normal in all survivors. Conclusions Our preliminary observations suggest that the tracheal volume flow during fetal breathing... [ABSTRACT FROM AUTHOR]

The objective of this study was to describe the normal blood flow velocity waveforms in the main branches of the right and left pulmonary arteries in the human fetus and to establish reference ranges for different Doppler parameters during the second half of pregnancy. Cross-sectional data were collected from 86 healthy human singleton fetuses between 18 and 38 weeks of gestation. With advancing gestation a significant increase (p < 0.001) in the peak systolic velocity, time averaged velocity and time velocity integral was observed. The pulsatility index decreased significantly (p < 0.05) in the same period, suggesting a decrease in the pulmonary arterial vascular resistance. The acceleration time (AT) and the ratio of AT to ejection time (AT/ET), described in postnatal cardiology as having an inverse correlation with mean arterial pressure, increased significantly (p < 0.001). This is possibly the result of decreased pulmonary arterial pressure. The data show that Doppler examination of blood flow in the main stem of both the right and the left pulmonary arteries of the fetus is feasible, and increases insight into the lung perfusion of the human fetus. The observed changes throughout gestation are in accordance with animal experiments showing an increase in perfusion as well as a decrease in the vascular resistance and pressure. [ABSTRACT FROM AUTHOR]