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Biomedical subjects

S Yagel

Publications and source records attributed to S Yagel.

At least 19 recordsLinked to original sources

3D and 4D ultrasound in fetal cardiac scanning: a new look at the fetal heart.

Over the last decade we have been witness to a burgeoning literature on three-dimensional (3D) and four-dimensional (4D) ultrasound-based studies of the fetal cardiovascular system. Recent advances in the technology of 3D/4D ultrasound systems allow almost real-time 3D/4D fetal heart scans. It appears that 3D/4D ultrasound in fetal echocardiography may make a significant contribution to interdisciplinary management team consultation, health delivery systems, parental counseling, and professional training. Our aim is to review the state of the art in 3D/4D fetal echocardiography through the literature and index cases of normal and anomalous fetal hearts.

Echocardiography, Four-Dimensional↗

Postpartum evaluation of the anal sphincter by transperineal three-dimensional ultrasound in primiparous women after vaginal delivery and following surgical repair of third-degree tears by the overlapping technique.

OBJECTIVE: Intrapartum damage to the anal sphincter is an important factor in fecal incontinence. Recognized lacerations occur in 0.36-8.4% of vaginal deliveries, and occult sphincter damage in up to 35% of primiparous women. We examined the role of three-dimensional transperineal ultrasound (3DTUS) in the evaluation of the anal sphincter in primiparous women after vaginal delivery and after surgical repair of third-degree intrapartum tears by the overlapping technique. METHODS: During 2004-2005 139 primiparous women without clinically recognized third- to fourth-degree anal sphincter tears were prospectively studied 24-72 h postpartum (Group 1) and 13 primiparous women were examined 48 h to 4 months following surgical repair of third-degree tears with the overlapping technique (Group 2). A 3D 5-9-MHz transvaginal probe was placed in the area of the fourchette and perineal body in transverse and sagittal planes and 2-4 volumes were stored. The parameters studied were: examination duration; continuity of the internal and external sphincters; occult sphincter damage; internal sphincter and external sphincter width-measured 1.5 cm from the distal margin of the anus-at the '12, 3, 6 and 9 o'clock positions'; length of the posterior internal sphincter. RESULTS: Scanning was possible in all women and the stored volumes were adequate in 127/139 (91.4%) cases. Mean examination time was 3.5 min. In Group 1, occult sphincter defect was suspected in 10/127 women (7.9%). These patients were excluded from measurement calculations, leaving 117 cases for analysis. The internal sphincter was consistently visualized in all the remaining patients (n = 117), while the external sphincter was fully visualized in 99/117 women (84.6%), and partially visualized in the remainder. Mean internal sphincter thickness was 2.60, 2.55, 2.60 and 2.72 mm at the 12, 3, 6 and 9 o'clock positions, respectively, and mean internal sphincter length was 3.34 cm. Mean external sphincter thickness was 4.15, 4.20, 4.21 and 4.20 mm at the 12, 3, 6 and 9 o'clock measurement points. In Group 2, 3DTUS confirmed anatomic abnormalities in all the women in the area surrounding the 12 o'clock position. Evaluation of sphincter tears and their position and length was possible using the longitudinal view. Thinning of the internal sphincter in the area of damage and thickening on the opposite side, the 'half moon sign', sphincter discontinuity, thickening of the external sphincter in the area of repair and abnormality of mucous folds, seemed to be common signs of third-degree intrapartum sphincter tears, even after repair. CONCLUSIONS: 3DTUS is an accessible and promising method for postpartum sphincter evaluation, that is apparently well tolerated by patients. Reference data for sphincter anatomy representative of findings at transperineal ultrasound in primiparous women in the postpartum period have been established.

Anal Canal↗

Management of Kell isoimmunization--evaluation of a Doppler-guided approach.

OBJECTIVE: To assess the role of peak systolic velocity in the middle cerebral artery (MCA-PSV) in the management of pregnancies complicated by Kell isoimmunization. METHODS: Sixteen fetuses were monitored by conventional protocol (Group 1) and eight fetuses by an MCA-PSV-guided protocol (Group 2). The conventional protocol included a weekly ultrasound evaluation and measurement of maternal anti-Kell titers every 4-6 weeks. In Group 2 Doppler assessment of the MCA-PSV was performed at intervals of 4 to 7 days and MCA-PSV>1.5 multiples of the median (MoM) was considered as an indication for fetal blood sampling (FBS). RESULTS: No parameter emerged as a reliable predictor of isoimmunization severity in Group 1. In Group 2, no FBS was necessary in one case since the MCA-PSV values obtained during the follow-up were <1.29 MoM. In two cases the first FBS was already indicated after 1 week of follow-up, but five other fetuses were followed for 3-9 weeks before FBS was indicated. All fetuses with MCA-PSV>1.5 MoM prior to intrauterine transfusion (IUT) had severe fetal anemia on FBS. In fetuses with severe anemia on the first FBS, the MCA-PSV values 7 days before the first FBS were <1.29 MoM (four cases), between 1.29 and 1.5 MoM (two cases) and >1.55 MoM (one case). CONCLUSIONS: In the management of Kell isoimmunization invasive procedures may be avoided by implementing MCA-PSV measurements. Delineation of appropriate intervals between reassessments, the reliability of MCA-PSV following repeated IUTs, and cut-off values for FBS await further study.

Adult↗

Rendering in fetal cardiac scanning: the intracardiac septa and the coronal atrioventricular valve planes.

OBJECTIVE: In this study we aimed to apply spatio-temporal image correlation (STIC) rendering to visualize the virtual planes of the interventricular and interatrial septa (IVS, IAS) as well as the atrioventricular (AV) annuli plane just distal to the semilunar valves (coronal atrioventricular (CAV) plane) in normal and pathological fetal hearts, to ascertain whether these planes add to fetal cardiac examination. METHODS: Unselected gravidae presenting for anatomy scan or patients referred for fetal echocardiography in the second and third trimesters of pregnancy with suspected or diagnosed cardiac malformation were scanned using the five planes technique with the STIC modality to obtain cardiac volume sets for each patient. Rendering capabilities were employed to obtain the 'virtual planes' to evaluate the IVS, IAS, AV annuli, and size and alignment of the great vessels. RESULTS: A total of 136 normal scans were performed to establish a learning curve for STIC acquisition and post-processing rendering and analysis. An additional 35 cases with cardiac anomalies were accrued. In 131/136 (96.3%) normal scans the IAS and IVS were visualized successfully, while in 127/136 (93.4%) normal fetuses the CAV plane was successfully visualized. In 13 anomalous cases the IVS plane improved ventricular septal defect (VSD) evaluation, and in four the IAS plane contributed to foramen ovale evaluation. The modality improved visualization of the septa and the assessment of the defects, as well as the foramen ovale flap and pattern of movement of the foramen ovale. In five cases the CAV plane improved evaluation of the alignment of the major vessels in relation to the AV annuli, and in three the evaluation of the semilunar valves, with or without malalignment of the great vessels. CONCLUSIONS: Rendering STIC technology allows the visualization of virtual planes (IAS, IVS, AV annuli-CAV plane), which can clarify our understanding of anatomical defects and may improve communication with the management team and family.

Adult↗

Prenatal diagnosis and outcome of congenital cytomegalovirus infection in twin pregnancies.

OBJECTIVE: To study the outcome of 20 twin pregnancies with evidence of primary or recurrent cytomegalovirus (CMV) infection during pregnancy. DESIGN: Observational study. SETTING: Two tertiary perinatal departments in Israel. POPULATION: Twenty women with twin pregnancies who were referred because of serologic investigation indicating CMV infection. Seventeen women had evidence of primary CMV infection, and three women appeared to have recurrent CMV infection. METHODS: Prenatal diagnosis was made by amniocentesis of both sacs after 21 weeks of gestation. CMV isolation was performed by culture on fibroblasts, shell vial technique and polymerase chain reaction (PCR) amplification of CMV DNA. After birth, the neonatal urine and saliva were cultured for CMV. MAIN OUTCOME MEASURES: Intrauterine CMV infection defined as positive PCR at amniotic fluid analysis and congenital CMV infection defined as positive CMV cultures after birth. RESULTS: Except for one, all women underwent amniocentesis of both gestational sacs. In 14 (70%) women, no evidence of vertical transmission to any of the 28 fetuses was found and none of the newborns had evidence of congenital CMV infection. Intrauterine infection was detected by amniocentesis in five women and by ultrasound findings with positive maternal serology in one. In three women, CMV was detected in only one amniotic sac. In five of our six total cases, both twins were found to have congenital CMV infection at birth, all of whom had dichorionic-diamniotic placentation, three fused and two separate. CONCLUSIONS: In twin gestations, as in singletons, intrauterine and congenital CMV infection occurs in about 30% of women with primary or recurrent infection. The placenta type did not predict if one or both twins would be infected. Our data do not exclude the possibility that intrauterine transmission of the virus from one fetus to the other can occur.

Adult↗

Fetal intracranial hemorrhage (fetal stroke): does grade matter?

OBJECTIVE: To determine if the severity of antenatally diagnosed hemorrhagic fetal brain insults and fetal stroke detected by ultrasound and magnetic resonance imaging (MRI) predicts postnatal neurodevelopmental prognosis. METHODS: The in-utero presentation and postnatal neurodevelopmental outcome of sonographically detected subdural hematoma or fetal stroke presenting as intraventricular hemorrhage (IVH) or intraparenchymal brain hemorrhage were investigated. RESULTS: Of 33 fetuses diagnosed with hemorrhagic brain lesions, 17 were electively terminated and two suffered intrauterine fetal demise. Thirteen were liveborn, seven by Cesarean delivery and six by spontaneous vaginal delivery. One case was lost to follow-up. Eight neonates had moderate to severe neurological deficit by a mean age of 35 (range, 6-96) months. One died at 2 months of age. These nine were diagnosed with Grade III-IV IVH in utero. Four neonates had normal neurological outcome by a mean age of 41 (range, 30-48) months; these four were diagnosed with subdural hematoma (n = 1) or Grade I-II IVH (n = 3) in utero. Fourteen cases were followed up with MRI, which confirmed ultrasound findings in 10 (71%) cases. In three (21%) cases MRI diagnosis was more accurate and the severity of grading was greater than that obtained on ultrasound imaging. Unilateral left hemispheric lesions were much more common than right-sided lesions (13 vs. 1, respectively). CONCLUSIONS: An antenatal sonographic diagnosis of fetal stroke with IVH Grade III-IV or with brain parenchymal involvement appears to be associated with poor neurological outcome. MRI may contribute to the accuracy of diagnosis, particularly in Grade II and III lesions. Left-sided unilateral lesions are more common than right-sided ones.

Developmental Disabilities↗

Mild tricuspid regurgitation: a benign fetal finding at various stages of pregnancy.

OBJECTIVE: Tricuspid regurgitation (TR) may accompany various anatomical malformations and/or dysfunction of the fetal right heart. It may also appear in an anatomically healthy heart. With improved ultrasound modalities, more cases than the previously estimated prevalence of fetal TR in the low-risk population are being diagnosed. The objective of this study was to determine the prevalence of mild fetal TR in a low-risk obstetric population. METHODS: In 157 low-risk pregnant women (age range, 18-42 years) undergoing both early second-trimester and mid-trimester targeted organ scanning, including complete fetal echocardiography according to the five transverse planes technique, the apical four-chamber view was visualized using gray-scale, color Doppler and spatiotemporal image correlation (STIC) ultrasound modalities, with optimal acquisition parameters. RESULTS: Mild-to-moderate TR was discovered in the early second-trimester scan in 131/157 (83.4%) fetuses. No cases of cardiac malformation were found. All fetuses showed normal flow in the ductus venosus, including in one case diagnosed with moderate TR. Only in 39 (24.8%) cases was mild TR still evident at the second, mid-trimester scan. Neonatal echocardiography revealed mild TR in eight (5.1%) cases. No cases of chromosomal anomalies were detected. CONCLUSION: Mild TR is a benign finding of a temporal nature in early pregnancy.

Adolescent↗

Human placental Hofbauer cells express sprouty proteins: a possible modulating mechanism of villous branching.

The development of the chorionic villous tree into a complex and organized ramified tubular network can be termed branching morphogenesis. Studying the molecular mechanisms involved in this process may contribute to the understanding of pregnancy complications such as preeclampsia. Sprouty (Spry) proteins are important regulators of branching morphogenesis and growth factor signaling. We analyzed the expression of Spry genes in human placenta. RT-PCR and immunohistochemistry were employed to detect placental Spry expression. Quantitative RT-PCR was used to assess the effect of FGF and reduced oxygen fraction on Spry gene expression. Spry 1, 2 and 3 expression was observed in placental tissue from all three trimesters. Our results reveal for the first time that Spry proteins are localized in the stroma of the chorionic villi, adjacent to cytotrophoblasts in areas of villous sprouting. Immunofluorescent double staining with anti-Spry and anti-CD68 confirmed that placental macrophages (Hofbauer cells) express Spry. Reduced oxygen fraction, FGF-4 and FGF-10 stimulated Spry-2 expression. Hofbauer cells also expressed c-Cbl, a protein that interacts with Spry. Placental expression of Spry and c-Cbl implies an important role for Hofbauer cells in placental development, possibly through a mesenchymal-epithelial interaction with trophoblasts. Regulation of Spry-2 expression by FGF-4 and FGF-10 suggests an orchestrated regulatory system that modulates villous branching.

Cells, Cultured↗

Vascular endothelial growth factor, epidermal growth factor and fibroblast growth factor-4 and -10 stimulate trophoblast plasminogen activator system and metalloproteinase-9.

Trophoblast invasion, accompanied by degradation of extracellular matrix, is crucial to normal pregnancy development, whereas shallow placental invasion and implantation likely plays a role in the subsequent development of pre-eclampsia. The growth factors vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and fibroblast growth factor (FGF) are placental growth factors that activate degradation of extracellular matrix. We determined the effect of VEGF, EGF, FGF-2, FGF-4 and FGF-10 on the plasminogen activator system of first trimester cytotrophoblasts cultured in vitro. We studied the activity of urokinase plasminogen activator (uPA), its inhibitor plasminogen activator inhibitor-1 (PAI-1), and 92 kDa gelatinase-B (matrix metalloproteinase-9, MMP-9), using protein gel and reversed gel zymography. The expression pattern of FGF-4 and FGF-10 in human placental sections was determined by immunohistochemistry. FGF-4 was expressed in first trimester villi stroma, primarily in endothelial cells. FGF-10 expression was localized to first trimester extravillous trophoblasts. VEGF, EGF, FGF-4 and FGF-10, but not FGF-2, stimulate the activity of trophoblast uPA, PAI-1 and MMP-9. These results support the hypothesis that specific growth factors modulate the invasive potential of trophoblasts, and therefore may play an important role in early placental development. Our findings may contribute to the understanding of the pathophysiology of diseases associated with shallow placentation, such as pre-eclampsia.

Epidermal Growth Factor↗

Adverse outcome of isolated fetal intra-abdominal umbilical vein varix despite close monitoring.

BACKGROUND AND OBJECTIVES: Fetal intra-abdominal umbilical vein (FIUV) varix-a focal dilatation of the umbilical vein-is an uncommon entity. Outcome varies from spontaneous resolution to fetal death. We describe here the experience of our center with this perplexing entity. METHODS: Case series review of seven cases of isolated FIUV treated in a tertiary care center from 2000 to 2003. RESULTS: We describe seven cases of isolated FIUV varix with varying natural history, follow-up strategies, and fetal outcome. In one of the cases, intrauterine fetal demise occurred despite close follow-up. CONCLUSIONS: We suggest that the course of FIUV is unpredictable, with a high fetal mortality rate. Close fetal monitoring with early delivery at 34 weeks' gestation should be advocated.

Abdomen↗

Application of free-hand three-dimensional echocardiography in the evaluation of fetal cardiac ejection fraction: a preliminary study.

OBJECTIVE: To investigate the feasibility of using free-hand three-dimensional (3D) echocardiography to evaluate fetal cardiac function. METHODS: 3D cardiac data were collected during screening examinations for 37 normal fetuses with gestational ages of between 16 and 26 weeks. Processing of the 3D volumes included separation of the end-diastolic and end-systolic slices, segmentation of right and left ventricles, measurement of end-diastolic and end-systolic volumes, and calculation of the ejection fraction (EF) for each ventricle. In 21 fetuses at 21-24 weeks, right and left ventricle volumes and EF were compared. RESULTS: Twenty-five cases were appropriate for final statistical analysis. The volume of the ventricles increased with gestational age and estimated fetal weight. There was no significant trend in the difference between the volumes and EF of the right and left ventricles in the 21-24-week subgroup. The mean right and left ventricular EF were 54 +/- 11.2% and 57.5 +/- 14.6%, respectively. The mean combined EF of ventricles during gestation was 55.1 +/- 10.7% and seemed to remain constant during the gestational ages studied. CONCLUSIONS: 3D echocardiography can provide estimates of ventricular volume and function and may in future be used for evaluation of fetuses with congenital heart disease and cardiac dysfunction.

Echocardiography, Three-Dimensional↗