Accuracy of Prenatal Ultrasound in Evaluating Placental Pathology Using Superb Microvascular Imaging: A Prospective Observation Study

Evaluation of fetal cerebral microvascular status and its relationship with fetal growth and development using microvascular imaging technique

The study conducted retrospective analysis design, aiming to explore the use of Microvascular Imaging Technique (MVFI) to assess fetal cerebral microcirculation and analyze the relationship between Microvascular Index (MVI) and fetal growth and development. 100 pregnant women who met the criteria for fetal growth restriction (FGR) provided in the Expert Consensus on Fetal Growth Restriction (2019 Edition) and underwent routine prenatal examinations at the Obstetrics and Gynecology Department of Peking University Third Hospital from January 2021 to June 2023 were selected as the study subjects. A normal fetus with a fetal weight less than 10 % can be classified as FGR, Pregnant women with fetal umbilical artery (UA) systolic and diastolic (S/D) values ≥3 were included in the observation group, while 200 pregnant women with normal fetuses were selected as the control group during the same period. The fetuses' change in both groups were measured using color Doppler ultrasound, including bi-parietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL). The cerebral microcirculation of the fetuses in both groups was evaluated using MVFI, and the MVI values were compared. The clinical characteristics of FGR fetuses with umbilical artery S/D ratio ≥ 3 were summarized, and the correlation between fetal cerebral microvascular status and fetal growth and development was analyzed using Pearson correlation analysis. The outcomes told that the BPD, HC, AC, and FL values of the fetuses in the control group were lower the other's value (P < 0.05), and the MVI and peak systolic velocity of the middle cerebral artery (MCA-PSV) values were also lower in the control group (P < 0.05). Pearson correlation analysis revealed a positive correlation between fetal growth and development and MVI and MCA-PSV values in FGR fetuses. In conclusion, MVFI can monitor and quantitatively analyze fetal intracranial microcirculation, visualize slow blood flow in microvascular structures, and this study provides preliminary evidence of the close relationship between fetal cerebral microcirculation and intrauterine growth and development.

Clinical value of serum SIRT1 combined with uterine hemodynamics in predicting disease severity and fetal growth restriction in preeclampsia

Background

To investigate the effect and correlation of serum SIRT1 combined with uterine hemodynamic parameters on disease severity and fetal uterine growth restriction in the progression of preeclampsia, and to evaluate its clinical value as potential markers.

Methods

A total of 100 patients with preeclampsia who were hospitalized in Qufu Normal University Hospital from June 2017 to June 2021 were selected as the research objects. According to the severity, they were divided into Mild group (62 cases) and Severe group (38 cases), and according to whether the fetal growth restriction was combined or not, they were divided into the Combined fetal growth restriction group (56 cases) and the Uncomplicated fetal growth restriction group (44 cases). Serum SIRT1 levels and uterine artery hemodynamic parameters were detected, and spearman analysis was used to evaluate the association of serum SIRT1 levels and uterine artery hemodynamic parameters (peak-to-trough ratio of arterial blood velocity, pulsatility index, resistance index) with disease severity (systolic blood pressure, diastolic blood pressure, and random urinary protein levels) and fetal growth restriction (femoral length, biparietal diameter, head circumference and neonatal weight); unsupervised PCA analysis, supervised PLS-DA analysis, Cluster heat map analysis, ROC curve and AUC analysis were used to evaluate the diagnostic value of serum SIRT1 levels combined with uterine artery hemodynamic parameters in the severity of disease and fetal growth restriction in patients with preeclampsia.

Results

Serum SIRT1 levels was decreased in patients with severe preeclampsia (p < 0.0001), arterial blood flow velocity peak-to-trough ratio, pulsatility index and resistance index were increased (p < 0.001; p < 0.0001), and serum SIRT1 levels and uterine artery hemodynamic parameters were closely related to disease severity (p < 0.001; p < 0.0001). In addition, the levels of serum SIRT1 in patients with preeclampsia combined with fetal growth restriction was decreased (p < 0.0001), the peak-to-trough ratio of arterial blood flow velocity, pulsatility index and resistance index were increased (p < 0.0001), and serum SIRT1 levels and uterine artery hemodynamics were closely related to fetal growth restriction (p < 0.0001). Unsupervised PCA analysis and supervised PLS-DA analysis showed that patients with different severity of disease and patients with or without fetal growth restriction were similar within groups, and there were significant differences between groups; cluster heat map analysis showed that mild and severe groups were stratified clustering, the combined fetal growth restriction group and the uncombined group were hierarchically clustered; ROC curve and AUC analysis showed that serum SIRT1 levels combined with uterine artery hemodynamic parameters had a significant effect on the severity of preeclampsia and whether combined with fetal growth restriction high diagnostic value.

Conclusions

Serum SIRT1 combined with uterine hemodynamic parameters in preeclampsia is closely related to disease severity and fetal growth restriction, and is expected to become potential biomarkers for early clinical intervention in patients.

Evaluation of placenta in patients with gestational diabetes using shear wave elastography and superb microvascular imaging

BACKGROUND

Gestational diabetes mellitus (GDM) is a common disease, and the placenta shows various functional and morphological changes in these patients. Superb microvascular imaging (SMI) and shear wave elastography (SWE) are innovative ultrasound (US) methods that provide detailed information about tissue vascularization and elasticity.

PURPOSE

To evaluate placental changes in patients with GDM with SMI and SWE methods.

MATERIAL AND METHODS

For this case-control study, 20 healthy and 20 women with GDM were included. Women at >21 weeks of pregnancy were evaluated with SMI and SWE by two independent radiologists. Mean SMI values and mean SWE values from three different region of interest-based measurements were compared between the two groups.

RESULTS

We identified that the mean SMI and SWE value ​​of the GDM group was found to be significantly higher than that of the control group (P = 0.002, P = 0.001 respectively). Using a receiver operating characteristic curve, the cutoff value of the SMI ratio, which maximizes the prediction of the presence of GDM, was 0.1234279750 (95% confidence interval [CI] = 0.625-0.920), the SWE cut-off value was 15.5 kPa (95% CI = 0.794-0.989).

CONCLUSION

We have demonstrated that evaluation with SMI and SWE might allow quantitative assessment of the morphological changes of placentas in women with GDM. We believe that the use of innovative methods such as SMI and SWE in addition to conventional US examinations in daily practice and studies will provide significant clinical benefits to patient management.

B-Flow/Spatiotemporal Image Correlation M-Mode and Contrast-Enhanced/Microbubble Ultrasonography Quantification of Spiral Artery Distensibility and Placental Intervillous Perfusion in the First Trimester in a Primate Model of Impaired Spiral Artery Remodeling

OBJECTIVE

During early human pregnancy, placental trophoblasts remodel spiral arteries into distensible low-resistance vessels to promote placental perfusion. We have established a model of impaired spiral artery remodeling (SAR) by elevating estradiol levels in the first trimester of baboon pregnancy. In the present study, B-flow/spatiotemporal image correlation (STIC) M-mode ultrasonography, a non-Doppler technology for sharp rendering of vessel dimensions, was used to determine whether spiral artery distensibility was altered in SAR-suppressed baboons. Contrast-enhanced ultrasound/microbubble imaging was also performed to determine whether it detected changes in placenta intervillous space perfusion in SAR-suppressed baboons.

METHODS

The two imaging procedures were performed in the first trimester in baboons not treated or treated with estradiol to suppress SAR.

RESULTS

Spiral artery distensibility, that is, luminal diameter at systole minus diameter at diastole, and volume flow as quantified by B-flow/STIC M-mode were 26% (p = 0.03) and 55% (p = 0.059) lower, respectively, in SAR-suppressed baboons. However, placental intervillous space flow rate and video intensity plateau levels reflecting blood perfusion, quantified by contrast-enhanced ultrasound/microbubble imaging, were unaltered in SAR-suppressed baboons.

CONCLUSION

The results indicate that B-flow/STIC M-mode ultrasonography provides a non-invasive method to detect reduced distensibility and, thus, function of spiral arteries across the cardiac cycle in the first trimester in a primate model of impaired SAR. This study represents a first step in determining whether B-flow/STIC M-mode detects a similar defect in SAR early in adverse human pregnancy. This would provide an avenue to develop therapeutic modalities to prevent the devastating consequences of impaired SAR.

Ultrasound Doppler Findings in Fetal Vascular Malperfusion Due to Umbilical Cord Abnormalities: A Pilot Case Predictive for Cerebral Palsy

Fetal Vascular Malperfusion (FVM), a pathologic condition in the feto-placental circulation, is a chronic vaso-occlusive disorder in the umbilical venous blood flow. Microthrombi are caused by the umbilical cord's blood flow deficiency in a congested umbilical vein, which also causes microvascular damage to fetal organs, especially the brain, resulting in cerebral palsy. Thrombo-occlusive events also adversely affect the upstream chorionic or stem vessels in the placenta, resulting in fetal growth restriction and fetal hypoxia. An umbilical cord structural anomaly or multiple entanglements may involve FVM. In the present report, we demonstrate a case of FVM caused by multiple umbilical cord abnormalities obtained from antenatal ultrasound Doppler findings, and we also discuss FVM, which is chronically associated with CP, comparing the ultrasonographic findings to the pathologic findings.

Clinical Value of Serum SIRT1 Combined with Uterine Hemodynamics in Predicting Disease Severity and Fetal Growth Restriction in Preeclampsia

Objective

The sirtuin regulator 1-related enzyme (SIRT1) has been shown to play an important role in various pathophysiological processes. Our aim was to investigate the effect and correlation of serum SIRT1 combined with uterine hemodynamic parameters on disease severity and fetal uterine growth restriction in the progression of preeclampsia and to evaluate its clinical value as a potential marker.

Methods

A total of 100 patients with preeclampsia who were hospitalized in Qufu Normal University Hospital from June 2017 to June 2021 were selected as the research objects. According to the severity, they were divided into the mild (62 cases) and severe groups (38 cases), and according to whether the fetal growth restriction was combined or not, they were divided into the combined fetal growth restriction group (56 cases) and the uncomplicated fetal growth restriction group (44 cases). Serum SIRT1 expression and uterine artery hemodynamic parameters were detected, and Spearman analysis was used to evaluate the association of serum SIRT1 expression and uterine artery hemodynamic parameters (the peak-to-trough ratio of arterial blood velocity, the pulsatility index, and the resistance index) with disease severity (systolic blood pressure, diastolic blood pressure, and random urinary protein levels) and fetal growth restriction (femoral length, biparietal diameter, head circumference, and neonatal weight); unsupervised principal component analysis (PCA), supervised partial least-squares discrimination analysis (PLS-DA), cluster heat map analysis, the receiver operating characteristic (ROC) curve, and the area under curve (AUC) were used to evaluate the diagnostic value of serum SIRT1 expression combined with uterine artery hemodynamic parameters in the severity of disease and fetal growth restriction in patients with preeclampsia.

Results

Compared with patients with mild preeclampsia, serum SIRT1 expression was lower in patients with severe preeclampsia (p < 0.0001), the arterial blood flow velocity peak-to-trough ratio, pulsatility index, and resistance index were higher (p < 0.001; p < 0.0001); and serum SIRT1 expression and uterine artery hemodynamic parameters were closely related to disease severity (p < 0.001; p < 0.0001). In addition, the expression of serum SIRT1 in patients with preeclampsia combined with fetal growth restriction was lower than patients without preeclampsia (p < 0.0001); the peak-to-trough ratio of arterial blood flow velocity, the pulsatility index, and the resistance index were higher (p < 0.0001); and serum SIRT1 expression and uterine artery hemodynamics were closely related to fetal growth restriction (p < 0.0001). Unsupervised PCA analysis and supervised PLS-DA analysis showed that patients with different severity of disease and patients with or without fetal growth restriction were similar within the groups, and there were significant differences between the groups; cluster heat map analysis showed that the mild and severe groups were stratified clustering, and the combined fetal growth restriction group and the uncombined group were hierarchically clustered; ROC curve showed that the AUC of serum SIRT1 expression combined with uterine artery hemodynamic parameters was 0.776 in identifying the severity of preeclampsia and 0.956 in identifying the preeclampsia complicated by fetal growth restriction.

Conclusion

Serum SIRT1 combined with uterine hemodynamic parameters in preeclampsia is closely related to disease severity and fetal growth restriction and is expected to become a potential biomarker for early clinical intervention in patients.

Histological Assessment of the Placenta Accreta Spectrum Diagnosed with a 33-MHz Linear Probe during Cesarean Section

As placenta accreta spectrum (PAS) pathologies affect only the extremely thin tissues between the placenta and the uterine myometrium, superficial endometrial damage such as that caused by placenta creta and increta can be diagnosed only through histopathology. We performed direct uterine ultrasound of PAS using an ultrahigh frequency (33 MHz; i33LX9 Aplio i800) linear transducer. Here, we describe two cases with ultrasound images of placentas with PAS and a case without PAS to compare histological findings. In cases of PAS at the previous Cesarean scar, ultrasonography clearly revealed a thin uterine myometrium with some island-shaped sites where placental tissue was focally anchored to the uterine myometrium near the scar. Speckle blood flow pattern was absent at these sites during scanning with B-mode, but was detectable elsewhere. Histopathology samples from the same site revealed that villous tissue was directly attached to the uterine myometrium with a large area of infarction. In another case of diffuse PAS, speckle blood flow pattern was generally absent, and histopathology revealed deep fibrinoid deposits. We believe that histological evaluation following ultrasound use will improve the accuracy of ultrasound diagnosis and perinatal management of PAS in clinical practice.

Placental Tissue Destruction and Insufficiency from COVID-19 Causes Stillbirth and Neonatal Death from Hypoxic-Ischemic Injury: A Study of 68 Cases with SARS-CoV-2 Placentitis from 12 Countries

CONTEXT.—

Perinatal death is an increasingly important problem as the COVID-19 pandemic continues, but the mechanism of death has been unclear.

OBJECTIVE.—

To evaluate the role of the placenta in causing stillbirth and neonatal death following maternal infection with COVID-19 and confirmed placental positivity for SARS-CoV-2.

DESIGN.—

Case-based retrospective clinico-pathological analysis by a multinational group of 44 perinatal specialists from 12 countries of placental and autopsy pathology findings from 64 stillborns and 4 neonatal deaths having placentas testing positive for SARS-CoV-2 following delivery to mothers with COVID-19.

RESULTS.—

All 68 placentas had increased fibrin deposition and villous trophoblast necrosis and 66 had chronic histiocytic intervillositis, the three findings constituting SARS-CoV-2 placentitis. Sixty-three placentas had massive perivillous fibrin deposition. Severe destructive placental disease from SARS-CoV-2 placentitis averaged 77.7% tissue involvement. Other findings included multiple intervillous thrombi (37%; 25/68) and chronic villitis (32%; 22/68). The majority (19, 63%) of the 30 autopsies revealed no significant fetal abnormalities except for intrauterine hypoxia and asphyxia. Among all 68 cases, SARS-CoV-2 was detected from a body specimen in 16 of 28 cases tested, most frequently from nasopharyngeal swabs. Four autopsied stillborns had SARS-CoV-2 identified in internal organs.

CONCLUSIONS.—

The pathology abnormalities composing SARS-CoV-2 placentitis cause widespread and severe placental destruction resulting in placental malperfusion and insufficiency. In these cases, intrauterine and perinatal death likely results directly from placental insufficiency and fetal hypoxic-ischemic injury. There was no evidence that SARS-CoV-2 involvement of the fetus had a role in causing these deaths.