1,721,093 research outputs found
Four Dimensional Fetal Echocardiography [video]
No full textThe examination of the fetal heart is part of the comprehensive fetal scan, but this examination is still considered a challenge even for experienced sonographers. Over the years, the number of ultrasound techniques used in fetal cardiology impressively increased and no other fetal organ is examined with as many modalities as the fetal heart including high resolution two dimensional (2D) imaging, M-mode examination, spectral, color, power, high-definition digital Doppler, B flow as well as tissue Doppler. It is, however, common knowledge that despite the availability of all these technologies, screening programs, especially when limited to the study of the “four chamber view”, have shown disappointing low detection rates for congenital heart disease (CHD). Although the identification of CHD can be improved by routinely visualizing the outflow tracts, their diagnosis is greatly affected by the skill of the operator as well as his ability to interpret the findings.
Very recently, three- and four- dimensional (3D and 4D) technologies have been introduced in fetal cardiology and have revolutionized the way in which it is possible to study the heart. 4D ultrasonography may reduce the operator dependency of CHD diagnosis and adds the possibility to obtain offline virtual planes in cardiac examinations, views of the fetal heart difficult or impossible to obtain with conventional 2D ultrasound.
This new fetal cardiology ebook, we believe, will be of great value for all practicing clinicians wanting to start the study of the fetal heart with 4D ultrasonography. We have chosen a panel of contributors that are both leaders in this field and can represent the differences in practice between Europe and United States. This is a comprehensive guide intended for anyone interested in fetal heart scanning performing both routine screening ultrasonographic examinations and targeted heart scans. It aims to assist the reader with the following questions: how can I use this technology to acquire cardiac volumes?; how do I handle cardiac volume data sets after acquisition?; how can I improve diagnosis and definition of CHD? It is our hope that this book will provide a bridge between scientists using and testing new technologies for research purposes and clinicians wishing to improve their daily practice
Intrauterine growth restriction: diagnosis and management. A review
No full textIntrauterine growth restriction (IUGR) is the failure to achieve the genetically predetermined growth potential and may be caused by maternal, fetal, placental, and external factors. IUGR is associated not only with a marked increased risk in perinatal mortality and morbidity but also with long-term outcome risks. IUGR is clinically suspected when ultrasonographic estimates of fetal size, simmetry or weight result abnormal. Exclusion of structural and/or chromosomal anomalies and Doppler studies of maternal and fetal circulations is the most effective method to differentiate IUGR fetuses secondary to placental dysfunction from those secondary to aneuploidy, genetic syndromes, and intrauterine infections. This review summarizes the current knowledge about fetal hemodynamics in IUGR pregnancies and its relationship with the severity of the disease. A better understanding of fetal hemodynamic changes occurring in IUGR will likely lead to targeted monitoring intervals in such fetuses leading to an appropriate timing of delivery only when fetal risks exceed neonatal risks
The effects of fetal blood sampling and placental puncture on umbilical artery and fetal arterial vessels blood flow velocity waveforms
No full textThis study was performed to investigate whether fetal blood sampling and/or transplacental puncture are associated with changes of blood flow velocity waveforms in umbilical artery and fetal circulation. The pulsatility index (PI) was measured from umbilical artery, thoracic descending aorta, renal artery, and middle cerebral artery immediately before and after fetal blood sampling (n=28) or third trimester amniocentesis (n=32). No significant changes in H values were evidenced after amniocentesis performed either transamniotically (n=21) or transplacentally (n=11). Fetal blood sampling induced a significant decrease of PI values in all the vessels investigated. However, in presence of a transplacental procedure (n=15) the amplitude of the decrease of PI in umbilical artery was significantly higher than after a transamniotic procedure (n=13), while no differences were evidenced in the other vessels tested. These findings indicate that umbilical cord puncture at the time of fetal blood sampling is associated with a decrease in PI in umbilical artery and several peripheral arterial vessels. The isolated placental puncture does not induce Doppler-detectable hemodynamic effects, while in conjunction with cord needling, it increases the amplitude of the effects in umbilical artery
Prenatal diagnosis of gastroesophageal reflux by color and pulsed Doppler ultrasonography in a case of congenital pyloric atresia
No full textA case of pyloric atresia diagnosed in the third trimester is described. Real-time ultrasonographic examination revealed polyhydramnios, enlarged stomach, evident gastric peristalsis and esophageal dilatation. Color and pulsed Doppler studies of the gastroesophageal junction revealed the presence of a biphasic flow pattern that was consistent with gastroesophageal reflux
Role of sonographic automatic volume calculation in measuring fetal cardiac ventricular volumes using 4-dimensional sonography: comparison with virtual organ computer-aided analysis
No full textThe purpose of this study was to compare the agreement and reliability of virtual organ computer-aided analysis (VOCAL) and sonographic automatic volume calculation (sonoAVC) for measurements of ventricular volume from fetal heart data sets acquired by 4-dimensional sonography with spatiotemporal image correlation (STIC)
Assessment of corpus callosum biometric measurements at 18 to 32 weeks' gestation by 3-dimensional sonography
No full textThe purposes of this study were to construct reference limits for corpus callosum dimensions measured on images reconstructed from 3-dimensional (3D) sonography and to evaluate the reproducibility of these measurements
First trimester assessment of umbilical vein diameter by using the semi-automated system for nuchal translucency measurement
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