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Yehuda Ginosar - One of the best experts on this subject based on the ideXlab platform.
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bold mri demonstrates acute placental and Fetal Organ hypoperfusion with Fetal brain sparing in response to phenylephrine but not ephedrine
Placenta, 2020Co-Authors: Joel Shapiro, Yehuda Ginosar, Yuval Gielchinsky, Uriel Elchalal, Zohar Bromberg, Nathalie Corchianachmanson, Rinat AbramovitchAbstract:Abstract Introduction We previously reported blood oxygen level dependent MRI (BOLD-MRI) for monitoring placental and Fetal hemodynamic changes in mice following maternal hypercapnia. Here we use BOLD-MRI to compare the placental and Fetal hemodynamic effects of different maternal vasopressors in mice. Methods Pregnant ICR mice (n = 16; E17.5) anesthetized with pentobarbital (80 mg/kg i.p.) were placed supine in a 4.7-T Bruker Biospec MRI. Following baseline images, equipotential doses of ephedrine (10 mg/kg) or phenylephrine (10mcg/kg) were administered intravenously. Changes in placental and Fetal signal were analyzed from T2*-weighted gradient echo MR images (TR/TE = 147/10 ms). Different regions of interest (placenta, Fetal heart, Fetal liver and Fetal brain) were identified. Percentage change of BOLD-MRI signal intensity (SI) were presented as time curves. Results Ephedrine and phenylephrine elicited markedly different effects. Phenylephrine caused an approximate 50% reduction in placental, Fetal heart and Fetal liver BOLD-MRI-SI, but Fetal brain BOLD-MRI-SI was unchanged (statistically different from placenta and other Fetal Organs; p Discussion Phenylephrine induced BOLD-MRI-SI changes suggestive of placental and Fetal hypoperfusion with brain sparing. Ephedrine induced BOLD-MRI-SI changes suggestive of increased cardiac output; we speculate that reduced Fetal heart BOLD-MRI-SI may be due to increased Fetal myocardial oxygen extraction or metabolic acidosis. The result demonstrates the potential of BOLD-MRI as a non-invasive hemodynamic tool for assessing pharmacodynamics effects in the placental and fetus.
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bold mri demonstrates acute placental and Fetal Organ hypoperfusion with Fetal brain sparing during hypercapnia
Placenta, 2017Co-Authors: Yehuda Ginosar, Yuval Gielchinsky, Nathalie Nachmansson, Lital Hagai, Joel Shapiro, Uriel Elchalal, Rinat AbramovitchAbstract:Abstract Introduction We evaluated changes in placental and Fetal hemodynamics in rodents during acute hypercapnia using BOLD-MRI and Doppler ultrasound. Methods Animals were anesthetized with pentobarbital and, in consecutive 4-min periods, breathed: air, 21%O2:5%CO2, and 95%O2:5%CO2. BOLD-MRI: Pregnant ICR mice (n = 6; E17.5) were scanned in a 4.7-T Bruker Biospec spectrometer. Placenta and Fetal liver, heart and brain were identified on True-FISP images. Percent change in signal intensity (SI) were analyzed every 30 s from T2*-weighted GE images (TR/TE = 147/10 ms). Doppler: Pregnant Wistar rats (n = 6; E18-20) were anesthetized with pentobarbital and received abdominal Doppler ultrasound. Umbilical artery pulsatility index (PI) and Fetal heart rate were assessed at baseline and after two minutes of both hypercapnic challenges. Results BOLD-MRI: Normoxic-hypercapnia caused immediate marked reduction in SI in placenta (−44% ± 5.5; p Conclusions Brief maternal hypercapnic challenge caused BOLD-MRI changes consistent with acute placental and Fetal hypoperfusion with Fetal brain sparing. The same challenge caused increased umbilical artery PI and Fetal bradycardia on Doppler ultrasound, suggestive for acute Fetal asphyxia. BOLD-MRI may be a suitable noninvasive imaging strategy to assess placental and Fetal Organ hemodynamics.
Rinat Abramovitch - One of the best experts on this subject based on the ideXlab platform.
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bold mri demonstrates acute placental and Fetal Organ hypoperfusion with Fetal brain sparing in response to phenylephrine but not ephedrine
Placenta, 2020Co-Authors: Joel Shapiro, Yehuda Ginosar, Yuval Gielchinsky, Uriel Elchalal, Zohar Bromberg, Nathalie Corchianachmanson, Rinat AbramovitchAbstract:Abstract Introduction We previously reported blood oxygen level dependent MRI (BOLD-MRI) for monitoring placental and Fetal hemodynamic changes in mice following maternal hypercapnia. Here we use BOLD-MRI to compare the placental and Fetal hemodynamic effects of different maternal vasopressors in mice. Methods Pregnant ICR mice (n = 16; E17.5) anesthetized with pentobarbital (80 mg/kg i.p.) were placed supine in a 4.7-T Bruker Biospec MRI. Following baseline images, equipotential doses of ephedrine (10 mg/kg) or phenylephrine (10mcg/kg) were administered intravenously. Changes in placental and Fetal signal were analyzed from T2*-weighted gradient echo MR images (TR/TE = 147/10 ms). Different regions of interest (placenta, Fetal heart, Fetal liver and Fetal brain) were identified. Percentage change of BOLD-MRI signal intensity (SI) were presented as time curves. Results Ephedrine and phenylephrine elicited markedly different effects. Phenylephrine caused an approximate 50% reduction in placental, Fetal heart and Fetal liver BOLD-MRI-SI, but Fetal brain BOLD-MRI-SI was unchanged (statistically different from placenta and other Fetal Organs; p Discussion Phenylephrine induced BOLD-MRI-SI changes suggestive of placental and Fetal hypoperfusion with brain sparing. Ephedrine induced BOLD-MRI-SI changes suggestive of increased cardiac output; we speculate that reduced Fetal heart BOLD-MRI-SI may be due to increased Fetal myocardial oxygen extraction or metabolic acidosis. The result demonstrates the potential of BOLD-MRI as a non-invasive hemodynamic tool for assessing pharmacodynamics effects in the placental and fetus.
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bold mri demonstrates acute placental and Fetal Organ hypoperfusion with Fetal brain sparing during hypercapnia
Placenta, 2017Co-Authors: Yehuda Ginosar, Yuval Gielchinsky, Nathalie Nachmansson, Lital Hagai, Joel Shapiro, Uriel Elchalal, Rinat AbramovitchAbstract:Abstract Introduction We evaluated changes in placental and Fetal hemodynamics in rodents during acute hypercapnia using BOLD-MRI and Doppler ultrasound. Methods Animals were anesthetized with pentobarbital and, in consecutive 4-min periods, breathed: air, 21%O2:5%CO2, and 95%O2:5%CO2. BOLD-MRI: Pregnant ICR mice (n = 6; E17.5) were scanned in a 4.7-T Bruker Biospec spectrometer. Placenta and Fetal liver, heart and brain were identified on True-FISP images. Percent change in signal intensity (SI) were analyzed every 30 s from T2*-weighted GE images (TR/TE = 147/10 ms). Doppler: Pregnant Wistar rats (n = 6; E18-20) were anesthetized with pentobarbital and received abdominal Doppler ultrasound. Umbilical artery pulsatility index (PI) and Fetal heart rate were assessed at baseline and after two minutes of both hypercapnic challenges. Results BOLD-MRI: Normoxic-hypercapnia caused immediate marked reduction in SI in placenta (−44% ± 5.5; p Conclusions Brief maternal hypercapnic challenge caused BOLD-MRI changes consistent with acute placental and Fetal hypoperfusion with Fetal brain sparing. The same challenge caused increased umbilical artery PI and Fetal bradycardia on Doppler ultrasound, suggestive for acute Fetal asphyxia. BOLD-MRI may be a suitable noninvasive imaging strategy to assess placental and Fetal Organ hemodynamics.
C Lees - One of the best experts on this subject based on the ideXlab platform.
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minimally invasive Fetal autopsy using magnetic resonance imaging and percutaneous Organ biopsies clinical value and comparison to conventional autopsy
Ultrasound in Obstetrics & Gynecology, 2011Co-Authors: Andrew C G Breeze, David J Lomas, F A Jessop, P A K Set, A L Whitehead, J J Cross, G A Hackett, Ilse Joubert, C LeesAbstract:Objectives Autopsy is an important investigation following Fetal death or termination for Fetal abnormality. Postmortem magnetic resonance imaging (MRI) can provide macroscopic information of comparable quality to that of conventional autopsy in the event of perinatal death. It does not provide tissue for histological examination, which may limit the quality of counseling for recurrence risks and elucidation of the cause of death. We sought to examine the comparability and clinical value of a combination of postmortem MRI and percutaneous Fetal Organ biopsies (minimally invasive autopsy (MIA)) with conventional Fetal autopsy. Methods Forty-four fetuses underwent postmortem MRI and attempted percutaneous biopsy (using surface landmarks) of major Fetal Organs (liver, lung, heart, spleen, kidney, adrenal and thymus) following Fetal death or termination for abnormality, prior to conventional autopsy, which was considered the ‘gold standard’. We compared significant findings of the two examinations for both diagnostic information and clinical significance. Ancillary investigations (such as radiographs and placental histology) were regarded as common to the two forms of autopsy. Results In 21 cases conventional autopsy provided superior diagnostic information to that of MIA. In two cases the MIA provided superior diagnostic information to that of conventional autopsy, when autolysis prevented detailed examination of the Fetal brain. In the remaining 21 cases, conventional autopsy and MIA provided equivalent diagnostic information. With regard to clinical significance, however, in 32 (72.7%) cases, the MIA provided information of at least equivalent clinical significance to that of conventional autopsy. In no case did the addition of percutaneous biopsies reveal information of additional clinical significance. Conclusions Although in some cases MRI may provide additional information, conventional perinatal autopsy remains the gold standard for the investigation of Fetal death. The utility of adding percutaneous Organ biopsies, without imaging guidance, to an MRI-based Fetal autopsy remains unproven. Postmortem MRI, combined with ancillary investigations such as placental histology, external examination by a pathologist, cytogenetics and plain radiography provided information of equivalent clinical significance in the majority of cases. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
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postmortem Fetal Organ volumetry using magnetic resonance imaging and comparison to Organ weights at conventional autopsy
Ultrasound in Obstetrics & Gynecology, 2008Co-Authors: Andrew C G Breeze, Ferdia A Gallagher, David J Lomas, Gordon C S Smith, C LeesAbstract:Objectives Following perinatal death, Organ weights at autopsy may provide evidence of growth restriction and pulmonary hypoplasia. Whilst postmortem magnetic resonance imaging (MRI) may provide comparable information to autopsy about structural abnormalities, its ability to provide reproducible data about Organ size has yet to be determined. We examined the feasibility of using postmortem MRI to provide estimates of Organ size and weight. Methods Twenty-five fetuses of gestational age from 16 to 40 weeks underwent postmortem MRI prior to autopsy. Fetal lung, brain and liver volume estimations were performed by two observers using the stereology technique on postmortem MRI slices. Fetal lung, brain and liver weights were recorded at autopsy. Organ volume estimates and autopsy Organ weights were compared using regression analysis, and estimates of Fetal Organ densities made. Interobserver variability was assessed using a Bland–Altman plot. Receiver–operating characteristics curve (ROC) analysis compared MRI brain : liver volume ratios to autopsy brain : liver weight ratios. Results A linear relationship between Organ volume estimates and Organ weight was observed. Estimated densities for the Fetal brain, liver and lung were 1.08 g/cm3, 1.15 g/cm3 and 1.15 g/cm3, respectively. Interobserver 5th and 95th percentile limits of agreement for Fetal brain, liver and lung were − 5.4% to + 7.9%, − 11.8% to + 8.3% and − 14.3% to + 8.7%, respectively. For MRI Organ volumes to detect a brain weight : liver weight ratio ≥ 4, ROC analysis demonstrated an area under the curve of 0.61, with an optimal cut-off of 4.1. Conclusion Postmortem MRI Organ volumetry can be used to estimate weights of major Fetal Organs. This may increase the information obtained from a minimally-invasive perinatal autopsy, particularly in the context of pulmonary hypoplasia and intrauterine growth restriction, where differential Organ growth plays a major part in assessment of the underlying pathology. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
David J Lomas - One of the best experts on this subject based on the ideXlab platform.
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minimally invasive Fetal autopsy using magnetic resonance imaging and percutaneous Organ biopsies clinical value and comparison to conventional autopsy
Ultrasound in Obstetrics & Gynecology, 2011Co-Authors: Andrew C G Breeze, David J Lomas, F A Jessop, P A K Set, A L Whitehead, J J Cross, G A Hackett, Ilse Joubert, C LeesAbstract:Objectives Autopsy is an important investigation following Fetal death or termination for Fetal abnormality. Postmortem magnetic resonance imaging (MRI) can provide macroscopic information of comparable quality to that of conventional autopsy in the event of perinatal death. It does not provide tissue for histological examination, which may limit the quality of counseling for recurrence risks and elucidation of the cause of death. We sought to examine the comparability and clinical value of a combination of postmortem MRI and percutaneous Fetal Organ biopsies (minimally invasive autopsy (MIA)) with conventional Fetal autopsy. Methods Forty-four fetuses underwent postmortem MRI and attempted percutaneous biopsy (using surface landmarks) of major Fetal Organs (liver, lung, heart, spleen, kidney, adrenal and thymus) following Fetal death or termination for abnormality, prior to conventional autopsy, which was considered the ‘gold standard’. We compared significant findings of the two examinations for both diagnostic information and clinical significance. Ancillary investigations (such as radiographs and placental histology) were regarded as common to the two forms of autopsy. Results In 21 cases conventional autopsy provided superior diagnostic information to that of MIA. In two cases the MIA provided superior diagnostic information to that of conventional autopsy, when autolysis prevented detailed examination of the Fetal brain. In the remaining 21 cases, conventional autopsy and MIA provided equivalent diagnostic information. With regard to clinical significance, however, in 32 (72.7%) cases, the MIA provided information of at least equivalent clinical significance to that of conventional autopsy. In no case did the addition of percutaneous biopsies reveal information of additional clinical significance. Conclusions Although in some cases MRI may provide additional information, conventional perinatal autopsy remains the gold standard for the investigation of Fetal death. The utility of adding percutaneous Organ biopsies, without imaging guidance, to an MRI-based Fetal autopsy remains unproven. Postmortem MRI, combined with ancillary investigations such as placental histology, external examination by a pathologist, cytogenetics and plain radiography provided information of equivalent clinical significance in the majority of cases. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
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postmortem Fetal Organ volumetry using magnetic resonance imaging and comparison to Organ weights at conventional autopsy
Ultrasound in Obstetrics & Gynecology, 2008Co-Authors: Andrew C G Breeze, Ferdia A Gallagher, David J Lomas, Gordon C S Smith, C LeesAbstract:Objectives Following perinatal death, Organ weights at autopsy may provide evidence of growth restriction and pulmonary hypoplasia. Whilst postmortem magnetic resonance imaging (MRI) may provide comparable information to autopsy about structural abnormalities, its ability to provide reproducible data about Organ size has yet to be determined. We examined the feasibility of using postmortem MRI to provide estimates of Organ size and weight. Methods Twenty-five fetuses of gestational age from 16 to 40 weeks underwent postmortem MRI prior to autopsy. Fetal lung, brain and liver volume estimations were performed by two observers using the stereology technique on postmortem MRI slices. Fetal lung, brain and liver weights were recorded at autopsy. Organ volume estimates and autopsy Organ weights were compared using regression analysis, and estimates of Fetal Organ densities made. Interobserver variability was assessed using a Bland–Altman plot. Receiver–operating characteristics curve (ROC) analysis compared MRI brain : liver volume ratios to autopsy brain : liver weight ratios. Results A linear relationship between Organ volume estimates and Organ weight was observed. Estimated densities for the Fetal brain, liver and lung were 1.08 g/cm3, 1.15 g/cm3 and 1.15 g/cm3, respectively. Interobserver 5th and 95th percentile limits of agreement for Fetal brain, liver and lung were − 5.4% to + 7.9%, − 11.8% to + 8.3% and − 14.3% to + 8.7%, respectively. For MRI Organ volumes to detect a brain weight : liver weight ratio ≥ 4, ROC analysis demonstrated an area under the curve of 0.61, with an optimal cut-off of 4.1. Conclusion Postmortem MRI Organ volumetry can be used to estimate weights of major Fetal Organs. This may increase the information obtained from a minimally-invasive perinatal autopsy, particularly in the context of pulmonary hypoplasia and intrauterine growth restriction, where differential Organ growth plays a major part in assessment of the underlying pathology. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Andrew C G Breeze - One of the best experts on this subject based on the ideXlab platform.
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minimally invasive Fetal autopsy using magnetic resonance imaging and percutaneous Organ biopsies clinical value and comparison to conventional autopsy
Ultrasound in Obstetrics & Gynecology, 2011Co-Authors: Andrew C G Breeze, David J Lomas, F A Jessop, P A K Set, A L Whitehead, J J Cross, G A Hackett, Ilse Joubert, C LeesAbstract:Objectives Autopsy is an important investigation following Fetal death or termination for Fetal abnormality. Postmortem magnetic resonance imaging (MRI) can provide macroscopic information of comparable quality to that of conventional autopsy in the event of perinatal death. It does not provide tissue for histological examination, which may limit the quality of counseling for recurrence risks and elucidation of the cause of death. We sought to examine the comparability and clinical value of a combination of postmortem MRI and percutaneous Fetal Organ biopsies (minimally invasive autopsy (MIA)) with conventional Fetal autopsy. Methods Forty-four fetuses underwent postmortem MRI and attempted percutaneous biopsy (using surface landmarks) of major Fetal Organs (liver, lung, heart, spleen, kidney, adrenal and thymus) following Fetal death or termination for abnormality, prior to conventional autopsy, which was considered the ‘gold standard’. We compared significant findings of the two examinations for both diagnostic information and clinical significance. Ancillary investigations (such as radiographs and placental histology) were regarded as common to the two forms of autopsy. Results In 21 cases conventional autopsy provided superior diagnostic information to that of MIA. In two cases the MIA provided superior diagnostic information to that of conventional autopsy, when autolysis prevented detailed examination of the Fetal brain. In the remaining 21 cases, conventional autopsy and MIA provided equivalent diagnostic information. With regard to clinical significance, however, in 32 (72.7%) cases, the MIA provided information of at least equivalent clinical significance to that of conventional autopsy. In no case did the addition of percutaneous biopsies reveal information of additional clinical significance. Conclusions Although in some cases MRI may provide additional information, conventional perinatal autopsy remains the gold standard for the investigation of Fetal death. The utility of adding percutaneous Organ biopsies, without imaging guidance, to an MRI-based Fetal autopsy remains unproven. Postmortem MRI, combined with ancillary investigations such as placental histology, external examination by a pathologist, cytogenetics and plain radiography provided information of equivalent clinical significance in the majority of cases. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
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postmortem Fetal Organ volumetry using magnetic resonance imaging and comparison to Organ weights at conventional autopsy
Ultrasound in Obstetrics & Gynecology, 2008Co-Authors: Andrew C G Breeze, Ferdia A Gallagher, David J Lomas, Gordon C S Smith, C LeesAbstract:Objectives Following perinatal death, Organ weights at autopsy may provide evidence of growth restriction and pulmonary hypoplasia. Whilst postmortem magnetic resonance imaging (MRI) may provide comparable information to autopsy about structural abnormalities, its ability to provide reproducible data about Organ size has yet to be determined. We examined the feasibility of using postmortem MRI to provide estimates of Organ size and weight. Methods Twenty-five fetuses of gestational age from 16 to 40 weeks underwent postmortem MRI prior to autopsy. Fetal lung, brain and liver volume estimations were performed by two observers using the stereology technique on postmortem MRI slices. Fetal lung, brain and liver weights were recorded at autopsy. Organ volume estimates and autopsy Organ weights were compared using regression analysis, and estimates of Fetal Organ densities made. Interobserver variability was assessed using a Bland–Altman plot. Receiver–operating characteristics curve (ROC) analysis compared MRI brain : liver volume ratios to autopsy brain : liver weight ratios. Results A linear relationship between Organ volume estimates and Organ weight was observed. Estimated densities for the Fetal brain, liver and lung were 1.08 g/cm3, 1.15 g/cm3 and 1.15 g/cm3, respectively. Interobserver 5th and 95th percentile limits of agreement for Fetal brain, liver and lung were − 5.4% to + 7.9%, − 11.8% to + 8.3% and − 14.3% to + 8.7%, respectively. For MRI Organ volumes to detect a brain weight : liver weight ratio ≥ 4, ROC analysis demonstrated an area under the curve of 0.61, with an optimal cut-off of 4.1. Conclusion Postmortem MRI Organ volumetry can be used to estimate weights of major Fetal Organs. This may increase the information obtained from a minimally-invasive perinatal autopsy, particularly in the context of pulmonary hypoplasia and intrauterine growth restriction, where differential Organ growth plays a major part in assessment of the underlying pathology. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.