Chapters authored
Prenatal Diagnosis of Down Syndrome
The chapter’s contribution to the book explores the prenatal modalities to diagnose Down syndrome (DS). The current knowledge in the field of genetic sonographic markers is presented, along the performance of current policies as well as the potential of new emerging genetic techniques. Besides the screening or testing pregnancy algorithms, the chapter describes the power of prenatal diagnostic techniques, namely, the advantages and the complications of the invasive genetic maneuvers. The progress in prenatal diagnosis of Down syndrome is one of the most important in prenatal medicine in the last decades. The methods vary in terms of detection rates, acceptability, costs, and potential complications. Although the early genetic screening was improved, ultrasound evaluation should not be dismissed, as the first-trimester sonography has the potential to diagnose the majority of major fetal abnormalities.
Part of the book: Advances in Research on Down Syndrome
Fetal Abdominal Wall Defects
Abdominal wall defects (AWDs) represent a group of congenital anomalies that can be diagnosed early during pregnancy even at the time of the first trimester assessment, with direct impact on pre- and postnatal fetal prognosis and management decisions. The most frequent anomalies in this group are gastroschisis and omphalocele. The key method available, that allows the detection of any deviation from the physiologic midgut herniation, is the ultrasound (US) assessment. A precise algorithmic scan approach is imposed not only for an accurate detection of any abdominal wall defect, but also for a proper location of the defect and of the spatial relation to the umbilical cord insertion, fundamentally important in differentiating among various malformations. Other structural or chromosomal anomalies should be excluded. Suitable multidisciplinary counseling should be considered. Unfortunately, in utero surgery, in these cases, has not been yet successful. Postnatal early interventions are usually required in specialized pediatric centers.
Part of the book: Congenital Anomalies
Birth Control and Family Planning Using Intrauterine Devices (IUDs)
Intrauterine devices (IUDs) represent one of the most important methods used for contraception. The methods vary in terms of efficiency, acceptability, costs, and potential complications. Early methods have been improved, and ultrasound (US) evaluation has become an important tool to diagnose the clear majority of IUDs complications. This chapter presents a comprehensive and up-to-date status regarding the use of intrauterine devices (IUDs) for birth control and family planning. The topics discussed in the manuscript will involve the current knowledge on the history, types, mechanisms, health benefits, and risks. More, the present paper presents the medical techniques for inserting and removing a IUD, and the role of US to confirm proper IUD placement. Also, this chapter offers practical guidance in managing problems of continuing users and discusses the clinical circumstances that require reconsideration of the contraception methods.
Part of the book: Family Planning
Congenital Abnormalities of the Fetal Face
Even at the early stages of gestation, the fetal face can be examined. There have been observations of the normal anatomy, such as orbits and the forehead, starting with the 12th week of gestation. However, nowadays, ultrasound equipment still cannot distinguish the soft tissues of the face, which are too thin. Yet, after the age of 14 weeks, we can easily examine the forehead, orbits, nose, lips, and ears. Recently, three-dimensional ultrasound (3D) images of the fetus can also be obtained. However, two-dimensional (2D) ultrasonographic (US) images are more easily, rapidly, efficiently, and accurately obtained. At the first stage of embryogenesis, the main part in the development of the fetal face is taken by the genetic factors. Later, the influence of the environment becomes more important. It is known that the outcome of chromosomal aberrations and of teratogenic factors is the facial malformation. Therefore, examining the facial dimorphism may get us useful hints in revealing chromosomal or genetic abnormalities. This chapter focuses on the fetal face anomalies more frequently found while performing the prenatal diagnosis. It is divided into anomalies of the orbits, nose, lip, palate, and mandible.
Part of the book: Congenital Anomalies
Congenital Abnormalities of the Fetal Heart
Congenital heart defects (CHDs) are the most frequent congenital malformations, the costliest hospital admissions for structural defects and the leading cause of infant general and malformations related mortality. Fetal echocardiography represents a skilled ultrasound examination, because of the complexity, physiological and structural particularities of the fetal heart. The efficiency of the cardiac scan is reported with great variation, depending on the scanning protocol, examiner experience and equipment quality but CHDs remains among the most frequently missed congenital abnormalities.
Part of the book: Congenital Anomalies
Abnormalities of the Placenta
The placenta is considered an important organ that evolves with the implantation of the blastocyst throughout the pregnancy. The placenta has an essential role in functions such as nutrition, excretion, and immunologic and endocrine function. The normal placenta is a round- or oval-shaped organ that attaches to the uterine wall and has roughly 22 cm in diameter and a thickness of about 2–2.5 cm and weighs about one sixth of the fetal birth weight. Thus, a normal development of the placenta is important for an uneventful embryonic and fetal development. Consequently, the placenta abnormalities can range from structural anomalies, to function disorders, to site of implantation abnormalities.
Part of the book: Congenital Anomalies
Fetal Central Nervous System Abnormalities
Central nervous system (CNS) is one of the most frequent sites for prenatal diagnosed congenital abnormalities (10 per 1000 live births, much higher than the heart—eight per 1000, kidneys—four per 1000, and other fetal systems). Due to the evolving pattern, ultrasound screening for fetal brain malformations is usually performed at 19–22 weeks’ gestation, but severe congenital anomalies can be diagnosed much earlier. This chapter is a short review, structured in eight subchapters: the first one is dedicated to the normal ultrasound aspect of different CNS segments, and the following ones are to detect pathology in prenatal life. We used many ultrasound images and tried to correlate the prenatal findings with the ones obtained postpartum/postabortum for each case, by means of pathology/imaging techniques.
Part of the book: Congenital Anomalies
The Antenatal Detection of Fetal Limb Anomalies
The etiology of fetal limb abnormalities is very complex, involving different risk factors: chromosomal abnormalities, gene disorders, intrauterine factors, maternal diseases, or exposure to different risk factors. The prevalence of fetal limb anomalies is reported to be approximately 6 in 10,000 live births, and the impairments of the upper limbs seem to present a higher incidence in comparison to the inferior limbs, more often are affected unilaterally and on the right side in comparison to the left side, some being isolate or may associate other anomalies, as a part of an underlying syndrome. According to the current guidelines, the assessment of the fetal limbs should be performed in the late first and early second trimester. Three-dimensional ultrasound provides a better understanding of the fetal anomaly for the parents and helps a better counseling, and it is used to confirm the anomalies detected by the conventional ultrasound. In cases of treatable anomalies, a multidisciplinary approach involving an obstetrician, geneticist, neonatologist, pediatrician, and pediatric orthopedic surgeon is essential to improve the postnatal outcome. Ultrasound examination and genetic counseling for the parents has an important benefit since some conditions present a genetic inheritance, and the recurrence rate in further pregnancies is very high.
Part of the book: Congenital Anomalies
The Hepatic Fetal Venous System
View all chaptersThe vascular architecture of the human liver is established at the end of the 10th week of gestation as a result of a complex process. Recent developments in ultrasonographic imaging facilitate the prenatal evaluation of this system. However, many of the involved mechanisms are poorly understood. The hepatic primordium is in contact with the vitelline veins and the umbilical veins, and by the end of the 6th week, the afferent venous system of the liver is acquired giving rise to the portal vein, the portal sinus, and the ductus venosus. The only afferent vein of the liver that remains open at birth is the portal vein. Also, the efferent venous system of the liver is formed and emerges from the vitelline veins.
Part of the book: Embryology Update