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Appearance of fetal posterior fossa at 11–14 weeks in fetuses with Dandy–Walker malformation or chromosomal anomalies
Volpe, P.; Contro, E.; Fanelli, T. ...
Ultrasound in obstetrics & gynecology,
June 2016, 2016-Jun, 2016-06-00, 20160601, Letnik:
47, Številka:
6
Journal Article
ABSTRACT
Objective
To describe the sonographic appearance of fetal posterior fossa anatomy at 11–14 weeks of pregnancy and to assess the outcome of fetuses with increased intracranial translucency ...
(IT) and/or brainstem‐to‐occipital bone (BSOB) diameter.
Methods
Reference ranges for brainstem (BS), IT and cisterna magna (CM) measurements, BSOB diameter and the BS : BSOB ratio were obtained from the first‐trimester ultrasound examination of 233 fetuses with normal postnatal outcome (control group). The intraobserver and interobserver variability of measurements were investigated using 73 stored ultrasound images. In addition, a study group of 17 fetuses with increased IT and/or BSOB diameter was selected to assess outcome.
Results
No significant intraobserver or interobserver variability was found for any measurement in the control group. In the study group, IT was increased in all cases and BSOB diameter was above the 95th centile of the calculated normal range in all but two (88%) cases. In 13/17 study cases, only two of the three posterior brain spaces were recognized on ultrasound. These 13 fetuses had a larger BSOB diameter than did the four cases that showed all three posterior brain spaces, and had severe associated anomalies including Dandy–Walker malformation (DWM) and/or chromosomal anomalies.
Conclusions
Visualization of the fetal posterior fossa anatomy at 11–14 weeks' gestation is feasible. Increased fluid in the posterior brain at 11–14 weeks, particularly in the case of non‐visibility of the septation that divides the future fourth ventricle from the CM, is an important risk factor for cystic posterior fossa malformations, in particular DWM, and/or chromosomal aberrations. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
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Ultrasound diagnosis of placental and umbilical cord anomalies in singleton pregnancies resulting from in-vitro fertilization
Larcher, L.; Jauniaux, E.; Lenzi, J. ...
Placenta (Eastbourne),
January 2023, 2023-01-00, 20230101, Letnik:
131
Journal Article
placental anomalies can affect fetal and maternal outcome due to severe maternal hemorrhage potentially resulting in hysterectomy and cord accident including abruption that can determine fetal damage ...
or death. The aims of our study are to determine if the rate of placental and umbilical cord anomalies are more common in IVF singleton pregnancies compared to spontaneous pregnancies; to evaluate the role of ultrasound in screening for these anomalies and to investigate if oocyte donor fertilization is an additional risk factor for the development of these anomalies.
this was a prospective cohort study involving two tertiary centers. Patients with a singleton pregnancy conceived with IVF and patients presenting with a spontaneous conception were recruited between 1st May 2019 to 31st March 2021. A total of 634 pregnancies were enrolled in the study. All patients underwent similar antenatal care, which included ultrasound examinations at 11–14, 19–22 and 33–35 weeks. Ultrasound findings of placental and/or umbilical cord abnormalities were recorded using the same protocol for both groups and confirmed after birth.
IVF pregnancies had a significantly higher risk of low-lying placenta, placenta previa, bilobed placenta and velamentous cord insertion (VCI) compared with spontaneous pregnancies. In the heterologous subgroup there was a significant increased incidence of placenta accreta spectrum (PAS) disorders than in spontaneous pregnancies. All these anomalies were identified prenatally on ultrasound imaging and confirmed at birth.
IVF pregnancies in general and those resulting from donor oocyte in particular are at higher risk of placental and umbilical cord abnormalities compared to spontaneous pregnancies. These anomalies can be diagnosed accurately at the mid-trimester detailed fetal anomaly scan and our findings support the need for a targeted ultrasound screening of these anomalies in IVF pregnancies.
•IVF pregnancies are at higher risk of placental abnormalities compared to spontaneous.•Heterologous IVF pregnancies are at higher risk of placenta accreta spectrum.•US has a high diagnostic accuracy in detecting placental anomalies prenatally.
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Maternal cardiac function in normal twin pregnancy: a longitudinal study
Kuleva, M.; Youssef, A.; Maroni, E. ...
Ultrasound in obstetrics & gynecology,
November 2011, Letnik:
38, Številka:
5
Journal Article
Objective
To investigate maternal cardiac function in a cohort of uncomplicated twin gestations assessed longitudinally.
Methods
Women with twin pregnancies were enrolled prospectively and underwent ...
serial maternal echocardiography at 20–23 weeks, 26–29 weeks and 30–33 weeks of gestation. Patients were excluded if any of these complications occurred after recruitment: delivery < 34 weeks; pre‐eclampsia or gestational hypertension; small‐for‐gestational age neonates (birth weight of one or both twins < 5th centile for gestational age). Cardiac findings were compared with those obtained at the same gestational age periods in a group of singleton gestations.
Results
A group of 20 uncomplicated twin gestations was obtained for analysis and 10 singleton pregnancies were then selected as controls. At each visit, mean ± SD cardiac output (CO) was significantly higher in twins than in singletons (6.55 ± 0.82 vs 5.62 ± 0.82 L/min, P = 0.007 at 20–23 weeks; 7.31 ± 0.74 vs 6.39 ± 0.74 L/min, P = 0.003 at 26–29 weeks; 7.50 ± 0.89 vs 6.68 ± 0.65 L/min, P = 0.015 at 30–33 weeks), whereas total vascular resistance (TVR) was lower (1005 ± 137 vs 1179 ± 199 dynes × s/cm5, P = 0.009 at 20–23 weeks; 924 ± 100 vs 1070 ± 138 dynes × s/cm5, P = 0.003 at 26–29 weeks; 929 ± 96 vs 1031 ± 122 dynes × s/cm5, P = 0.018 at 30–33 weeks). In both twins and singletons, CO showed a significant increase while TVR decreased significantly throughout the assessed pregnancy time period.
Conclusion
In twin gestation, maternal cardiac function apparently undergoes more profound changes compared with in singleton gestation, as testified by higher CO and lower TVR values at each stage of pregnancy starting from the mid‐trimester. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
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Normal and abnormal appearance of fetal ganglionic eminence on second‐trimester three‐dimensional ultrasound
Contro, E.; Volpe, N.; Larcher, L. ...
Ultrasound in obstetrics & gynecology,
September 2023, Letnik:
62, Številka:
3
Journal Article
ABSTRACT
Objectives
To describe the appearance and size of the ganglionic eminence (GE) in normal fetuses on midtrimester three‐dimensional (3D) neurosonography and to report on the association ...
between GE alterations (cavitation or enlargement) and malformation of cortical development (MCD).
Methods
This was a prospective multicenter cohort study of normal fetuses and a retrospective analysis of pathological cases with MCD. From January 2022 to June 2022, patients attending our tertiary centers for an expert fetal brain scan were recruited for the purpose of the study. A 3D volume of the fetal head, starting from the sagittal plane, was acquired in apparently normal fetuses using a transabdominal or transvaginal approach. Stored volume datasets were then evaluated independently by two expert operators. Two measurements (longitudinal diameter and transverse diameter) of the GE in the coronal view were obtained twice by each operator. Intra‐ and interobserver measurement variation was calculated. Reference ranges for GE measurements were calculated in the normal population. A previously stored volume dataset of 60 cases with MCD was also analyzed independently by the two operators using the same method in order to assess if GE abnormalities (cavitation or enlargement) were present. Postnatal follow‐up was obtained in all cases.
Results
In the study period, 160 normal fetuses between 19 and 22 weeks of gestation were included in the study. The GE was visible in the coronal plane on 3D neurosonography in 144 (90%) cases and was not clearly visible in the remaining 16 (10%) cases. The intra‐ and interobserver agreement was almost perfect for the longitudinal diameter, with an intraclass correlation coefficient (ICC) of 0.90 (95% CI, 0.83–0.93) and 0.90 (95% CI, 0.86–0.92), respectively, and substantial for the transverse diameter, with an ICC of 0.80 (95% CI, 0.70–0.87) and 0.64 (95% CI, 0.53–0.72), respectively. A retrospective analysis of 50 cases with MCD in the second trimester showed that GE enlargement was present in 12 cases and GE cavitation was present in four cases.
Conclusions
Systematic assessment of the GE in fetuses at 19–22 weeks of gestation is feasible on 3D neurosonography, with good reproducibility in normal cases. Cavitation or enlargement of the GE can be demonstrated in fetuses with MCD. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
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Diagnostic accuracy of prenatal ultrasound in coarctation of aorta: systematic review and individual participant data meta‐analysis
Villalaín, C.; D'Antonio, F.; Flacco, M. E. ...
Ultrasound in obstetrics & gynecology,
April 2024, 2024-04-00, 20240401, Letnik:
63, Številka:
4
Journal Article
ABSTRACT
Objective
To determine the diagnostic accuracy of prenatal ultrasound in detecting coarctation of the aorta (CoA).
Methods
An individual participant data meta‐analysis was performed to ...
report on the strength of association and diagnostic accuracy of different ultrasound signs in detecting CoA prenatally. MEDLINE, EMBASE and CINAHL were searched for studies published between January 2000 and November 2021. Inclusion criteria were fetuses with suspected isolated CoA, defined as ventricular and/or great vessel disproportion with right dominance on ultrasound assessment. Individual participant‐level data were obtained by two leading teams. PRISMA‐IPD and PRISMA‐DTA guidelines were used for extracting data, and the QUADAS‐2 tool was used for assessing quality and applicability. The reference standard was CoA, defined as narrowing of the aortic arch, diagnosed after birth. The most commonly evaluated parameters on ultrasound, both in B‐mode and on Doppler, constituted the index test. Summary estimates of sensitivity, specificity, diagnostic odds ratio (DOR) and likelihood ratios were computed using the hierarchical summary receiver‐operating‐characteristics model.
Results
The initial search yielded 72 studies, of which 25 met the inclusion criteria. Seventeen studies (640 fetuses) were included. On random‐effects logistic regression analysis, tricuspid valve/mitral valve diameter ratio > 1.4 and > 1.6, aortic isthmus/arterial duct diameter ratio < 0.7, hypoplastic aortic arch (all P < 0.001), aortic isthmus diameter Z‐score of < −2 in the sagittal (P = 0.003) and three‐vessel‐and‐trachea (P < 0.001) views, pulmonary artery/ascending aorta diameter ratio > 1.4 (P = 0.048) and bidirectional flow at the foramen ovale (P = 0.012) were independently associated with CoA. Redundant foramen ovale was inversely associated with CoA (P = 0.037). Regarding diagnostic accuracy, tricuspid valve/mitral valve diameter ratio > 1.4 had a sensitivity of 72.6% (95% CI, 48.2–88.3%), specificity of 65.4% (95% CI, 46.9–80.2%) and DOR of 5.02 (95% CI, 1.82–13.9). The sensitivity and specificity values were, respectively, 75.0% (95% CI, 61.1–86.0%) and 39.7% (95% CI, 27.0–53.4%) for pulmonary artery/ascending aorta diameter ratio > 1.4, 47.8% (95% CI, 14.6–83.0%) and 87.6% (95% CI, 27.3–99.3%) for aortic isthmus diameter Z‐score of < –2 in the sagittal view and 74.1% (95% CI, 58.0–85.6%) and 62.0% (95% CI, 41.6–78.9%) for aortic isthmus diameter Z‐score of < –2 in the three‐vessel‐and‐trachea view. Hypoplastic aortic arch had a sensitivity of 70.0% (95% CI, 42.0–88.6%), specificity of 91.3% (95% CI, 78.6–96.8%) and DOR of 24.9 (95% CI, 6.18–100). The diagnostic yield of prenatal ultrasound in detecting CoA did not change significantly when considering multiple categorical parameters. Five of the 11 evaluated continuous parameters were independently associated with CoA (all P < 0.001) but all had low‐to‐moderate diagnostic yield.
Conclusions
Several prenatal ultrasound parameters are associated with an increased risk for postnatal CoA. However, diagnostic accuracy is only moderate, even when combinations of parameters are considered. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
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18.
One-step oxidehydration of glycerol to acrylic acid using ETS-10-like vanadosilicates
Paula, Alex Silva; Possato, Luiz Gustavo; Ratero, Davi Rubinho ...
Microporous and mesoporous materials,
09/2016, Letnik:
232
Journal Article
Vanadosilicates isostructural to ETS-10 and AM-6 microporous materials were synthesized hydrothermally using derivatives of cis- and trans-3,5-dimethyl-piperidine as organic structure directing ...
agents (SDAs) and were subsequently tested as heterogeneous catalysts for the oxidehydration of glycerol to acrylic acid. The best performances were obtained with vanadosilicates prepared with 1,1,3,5-tetramethyl piperidinum cations, which were capable of converting 93.6% of glycerol to acrylic acid in one step, with 85.4% selectivity. Other important chemicals such as acrolein (3.8%), propanal (2.3%), acetaldehyde (3.2%), acetic acid (2.5%), and propionic acid (1.4%) were produced in smaller amounts. The results clearly indicated that these vanadosilicates are potential multifunctional catalysts capable of performing the oxidehydration of glycerol to acrylic acid in a single step. Spectroscopic data obtained from 51VMAS-NMR, UV-Vis, XPS, and Raman scattering analyses suggested that the selectivity of these vanadosilicates for the oxidative dehydration of glycerol to acrylic acid could be attributed to the capacity of the vanadium species for dynamic adoption of multiple oxidation states during the catalytic reaction.
Display omitted
•ETS-10 like vanadosilicates were synthesized and characterized by several techniques.•Catalysts were used for glycerol conversion into acrylic acid in one step.•High glycerol conversion (93.6%) and acrylic acid selectivity (85.4%) were obtained.
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