- Email: [email protected]
1128
P40
Ultrasound in Medicine and Biology
organs or secundines (placenta, cord and membranes), or failure to adequately develop fetal fat reserves, or may be as dramatic as obvious fetal malformation, severe central nervous system structural damage or fetal death. Ultrasonographic examination is capable of detecting some of the subtle effects and most of the grave alterations that are typical of fetal infection. 1127 Ultrasound in fetal inflammatory response syndrome Mazor M, Smolin A, Burshtein E, Soroka University Medical Center, Ben Gurion University, Israel Infection/inflammation is an important and frequent mechanism of disease in women with premature labor or preterm premature rupture of membranes (PROM). Microorganisms in the amniotic cavity or maternal compartment may reach the human fetus and may lead to the development of an acute-phase response similar to that observed in adult patients with systemic inflammatory response syndrome, a serious condition characterized by multiple organ failure associated with sepsis. Fetal inflammatory response syndrome (FIRS), operationally defined as an elevated level of fetal plasma interleukin 6 (IL-6), is characterized by multiorgan involvement including the hematologic system, inflammatory cytokines and matrix metalloproteinases in the fetal circulation and activation of the fetal pituitary adrenal axis. FIRS is associated with the impending onset of preterm labor and delivery, periventricular leukomalacia, intraventricular hemorrhage, respiratory distress syndrome, neonatal sepsis and also long-term sequela including the development of bronchopulmonary dysplasia and cerebral palsy. Thus, the fetus of the mother with preterm labor or PROM may be critically ill in utero. Our goal is to recognize the early clinical manifestation of infection and FIRS. While the detection of microorganisms in amniotic fluid with culture techniques is the gold standard for the diagnosis of intraamniotic infection, cordocentesis is the method used to diagnose FIRS. However, with progressively improving imaging techniques, sonographic parameters may be used as noninvasive tools in the assessment of microbial invasion of the amniotic cavity and development of fetal inflammatory response. Previous ultrasonographic studies in women with PROM suggested that decreased biophysical activities (fetal breathing movements and gross body movements) were frequently associated with infection and the onset of spontaneous labor. In addition, there is significant relationship between the frequency of microbial invasion of the amniotic cavity, gestational age and the length of the uterine cervix. Another risk factor for microbial invasion in patients with preterm labor and intact membranes is the presence of amniotic fluid “sludge”. Patients with preterm PROM and reduced volume of amniotic fluid (amniotic fluid index ⬍5 cm) have significantly higher IL-6 concentrations in umbilical cord plasma at birth, higher rate of microbial invasion of the amniotic cavity and congenital neonatal sepsis. In a recent study we have described an association between patients with preterm PROM, intraamniotic infection and changes in fetal cardiac function consistent with increased left ventricular compliance. Fetuses with PROM had a higher early diastolic filling/atrial contraction peak velocity ratio and a higher early diastolic filling/atrial contraction velocity time integral ratio in the fetal mitral valve compared to those in women with uncomplicated pregnancies. These observations were also noted in fetuses with microbial invasion of intraamniotic cavity. Our findings suggest that fetal cardiac function is altered in women with PROM, and in particular in cases with intraamniotic infection. The sonographic findings have indicated that fetal thymus pathology as decreased volume and reduced corticomedullary ratio can be considered as another aspect of FIRS. We suggest that a combination of sonographic tests may serve as a better predictor of major fetal morbidity such as FIRS than either ultrasound parameter alone.
Volume 32, Number 5S, 2006 1128 Obstetrical sonography of teratogen exposure Kliewer M, University of Wisconsin, United States of America The true risks of teratogen exposure are usually poorly understood by patients, and even by the physicians, nurses and sonologists who attempt to provide counsel. Such misunderstandings can lead to both false assurances and false alarm, both unfounded dismissiveness and unwarranted anxiety. Teratogenesis results from genetic and environmental factors, which singly or in concert alter the normal development of the embryo. Those environmental agents, which can cause developmental abnormalities, include drugs, chemicals, infection, procedures, radiation and hyperthermia. The sonologist evaluating a patient with teratogen exposure will need to first assess the developmental risks of the exposure. This requires interviewing the patient to determine the agent, the dose and the timing of the exposure. There are four cardinal principles of teratogenicity, (1) teratogens exert their effects idiosyncratically across individuals of a population and between species, (2) susceptibility of a developing fetus to a teratogenic agent depends on the developmental stage of the fetus at the time of exposure, (3) teratogenic induction is a threshold phenomenon, (4) typically, teratogens cause characteristic patterns of malformations rather than single defects. Ultimately, the sonographic study of a pregnancy with a known teratogenic exposure will need to be more comprehensive and meticulous than routine studies. In addition to the routine fetal survey, additional scrutiny will need to be directed to the face, calvarium, spine, heart, limbs, hands and feet and genitalia, as well as the measures of fetal growth, amniotic fluid volume and placental function. Knowing the probable effects of a teratogen will help discipline and focus this rather formidable and extensive survey. 1129 Prenatal diagnosis of fetal neoplasms Cho JY, Samsung Cheil Hospital, Sungkyukwan University School of Medicine, Korea A variety of neoplasms can develop during the fetal life. Early detection and differential diagnosis of fetal neoplasm is important, which may alter the prenatal management and mode of delivery, and may facilitate immediate postnatal treatment. Teratoma is the most common congenital neoplasm. Brain teratoma usually appears as a large, solid and/or cystic tumor, often replacing normal brain tissue and sometimes eroding the skull. Fetal glioblastoma appears as a large homogeneous hyperechoic mass involving the supratentorial cerebral parenchyma. Mass effect and hydrocephalus are usually accompanied. The prevalence of hemorrhage is much higher than in children and adults. Lymphangioma is not a true neoplasm but a congenital lymphatic malformation, commonly develops at the posterior neck. It appears as unicameral or multilocular cystic masses with thin or thick-walled septa. Solid components and fluid-fluid levels due to bleeding may occur. A fetal oropharyngeal teratoma is also known as an epignathus and is easily detected by prenatal US. It usually appears as a large solid and cystic mass in the anterolateral aspect of the fetal face and neck. The stalk of mass is attached to the palate. Intracranial extension of the mass is not uncommon. Rhabdomyoma is the most common cardiac tumor. It appears as a single or multiple lesions. More than 50% is associated with tuberous sclerosis. On the prenatal US, rhabdomyoma appears as a homogeneous, echogenic, intracardiac mass, and is most commonly located in the ventricle, especially at the ventricular septum. Hemangioma is the most common benign hepatic tumor. It is often uncomplicated and resolve spontaneously during the first 2 y of life. It may be solitary or multiple, and the latter sometimes forming a part of generalized hemangiomatosis syndrome. It usually appears as a wellcircumscribed mass with heterogeneous internal echo. Color Doppler
Ultrasound in Medicine and Biology
organs or secundines (placenta, cord and membranes), or failure to adequately develop fetal fat reserves, or may be as dramatic as obvious fetal malformation, severe central nervous system structural damage or fetal death. Ultrasonographic examination is capable of detecting some of the subtle effects and most of the grave alterations that are typical of fetal infection. 1127 Ultrasound in fetal inflammatory response syndrome Mazor M, Smolin A, Burshtein E, Soroka University Medical Center, Ben Gurion University, Israel Infection/inflammation is an important and frequent mechanism of disease in women with premature labor or preterm premature rupture of membranes (PROM). Microorganisms in the amniotic cavity or maternal compartment may reach the human fetus and may lead to the development of an acute-phase response similar to that observed in adult patients with systemic inflammatory response syndrome, a serious condition characterized by multiple organ failure associated with sepsis. Fetal inflammatory response syndrome (FIRS), operationally defined as an elevated level of fetal plasma interleukin 6 (IL-6), is characterized by multiorgan involvement including the hematologic system, inflammatory cytokines and matrix metalloproteinases in the fetal circulation and activation of the fetal pituitary adrenal axis. FIRS is associated with the impending onset of preterm labor and delivery, periventricular leukomalacia, intraventricular hemorrhage, respiratory distress syndrome, neonatal sepsis and also long-term sequela including the development of bronchopulmonary dysplasia and cerebral palsy. Thus, the fetus of the mother with preterm labor or PROM may be critically ill in utero. Our goal is to recognize the early clinical manifestation of infection and FIRS. While the detection of microorganisms in amniotic fluid with culture techniques is the gold standard for the diagnosis of intraamniotic infection, cordocentesis is the method used to diagnose FIRS. However, with progressively improving imaging techniques, sonographic parameters may be used as noninvasive tools in the assessment of microbial invasion of the amniotic cavity and development of fetal inflammatory response. Previous ultrasonographic studies in women with PROM suggested that decreased biophysical activities (fetal breathing movements and gross body movements) were frequently associated with infection and the onset of spontaneous labor. In addition, there is significant relationship between the frequency of microbial invasion of the amniotic cavity, gestational age and the length of the uterine cervix. Another risk factor for microbial invasion in patients with preterm labor and intact membranes is the presence of amniotic fluid “sludge”. Patients with preterm PROM and reduced volume of amniotic fluid (amniotic fluid index ⬍5 cm) have significantly higher IL-6 concentrations in umbilical cord plasma at birth, higher rate of microbial invasion of the amniotic cavity and congenital neonatal sepsis. In a recent study we have described an association between patients with preterm PROM, intraamniotic infection and changes in fetal cardiac function consistent with increased left ventricular compliance. Fetuses with PROM had a higher early diastolic filling/atrial contraction peak velocity ratio and a higher early diastolic filling/atrial contraction velocity time integral ratio in the fetal mitral valve compared to those in women with uncomplicated pregnancies. These observations were also noted in fetuses with microbial invasion of intraamniotic cavity. Our findings suggest that fetal cardiac function is altered in women with PROM, and in particular in cases with intraamniotic infection. The sonographic findings have indicated that fetal thymus pathology as decreased volume and reduced corticomedullary ratio can be considered as another aspect of FIRS. We suggest that a combination of sonographic tests may serve as a better predictor of major fetal morbidity such as FIRS than either ultrasound parameter alone.
Volume 32, Number 5S, 2006 1128 Obstetrical sonography of teratogen exposure Kliewer M, University of Wisconsin, United States of America The true risks of teratogen exposure are usually poorly understood by patients, and even by the physicians, nurses and sonologists who attempt to provide counsel. Such misunderstandings can lead to both false assurances and false alarm, both unfounded dismissiveness and unwarranted anxiety. Teratogenesis results from genetic and environmental factors, which singly or in concert alter the normal development of the embryo. Those environmental agents, which can cause developmental abnormalities, include drugs, chemicals, infection, procedures, radiation and hyperthermia. The sonologist evaluating a patient with teratogen exposure will need to first assess the developmental risks of the exposure. This requires interviewing the patient to determine the agent, the dose and the timing of the exposure. There are four cardinal principles of teratogenicity, (1) teratogens exert their effects idiosyncratically across individuals of a population and between species, (2) susceptibility of a developing fetus to a teratogenic agent depends on the developmental stage of the fetus at the time of exposure, (3) teratogenic induction is a threshold phenomenon, (4) typically, teratogens cause characteristic patterns of malformations rather than single defects. Ultimately, the sonographic study of a pregnancy with a known teratogenic exposure will need to be more comprehensive and meticulous than routine studies. In addition to the routine fetal survey, additional scrutiny will need to be directed to the face, calvarium, spine, heart, limbs, hands and feet and genitalia, as well as the measures of fetal growth, amniotic fluid volume and placental function. Knowing the probable effects of a teratogen will help discipline and focus this rather formidable and extensive survey. 1129 Prenatal diagnosis of fetal neoplasms Cho JY, Samsung Cheil Hospital, Sungkyukwan University School of Medicine, Korea A variety of neoplasms can develop during the fetal life. Early detection and differential diagnosis of fetal neoplasm is important, which may alter the prenatal management and mode of delivery, and may facilitate immediate postnatal treatment. Teratoma is the most common congenital neoplasm. Brain teratoma usually appears as a large, solid and/or cystic tumor, often replacing normal brain tissue and sometimes eroding the skull. Fetal glioblastoma appears as a large homogeneous hyperechoic mass involving the supratentorial cerebral parenchyma. Mass effect and hydrocephalus are usually accompanied. The prevalence of hemorrhage is much higher than in children and adults. Lymphangioma is not a true neoplasm but a congenital lymphatic malformation, commonly develops at the posterior neck. It appears as unicameral or multilocular cystic masses with thin or thick-walled septa. Solid components and fluid-fluid levels due to bleeding may occur. A fetal oropharyngeal teratoma is also known as an epignathus and is easily detected by prenatal US. It usually appears as a large solid and cystic mass in the anterolateral aspect of the fetal face and neck. The stalk of mass is attached to the palate. Intracranial extension of the mass is not uncommon. Rhabdomyoma is the most common cardiac tumor. It appears as a single or multiple lesions. More than 50% is associated with tuberous sclerosis. On the prenatal US, rhabdomyoma appears as a homogeneous, echogenic, intracardiac mass, and is most commonly located in the ventricle, especially at the ventricular septum. Hemangioma is the most common benign hepatic tumor. It is often uncomplicated and resolve spontaneously during the first 2 y of life. It may be solitary or multiple, and the latter sometimes forming a part of generalized hemangiomatosis syndrome. It usually appears as a wellcircumscribed mass with heterogeneous internal echo. Color Doppler