Effects of uterine Doppler on midbrain growth and cortical development in late onset fetal growth restricted fetuses: a prospective cross-sectional study

OBJECTIVE

To investigate midbrain growth, including corpus callusum (CC), cerebellar vermis (CV) and cortical development in late fetal growth restriction (FGR) depending on uterine artery (UtA) Pulsatility Index (PI) values.

METHODS

This was a prospective study including singleton fetuses with late FGR characterized by abnormal cerebral placental ratio (CPR). According to UtA PI values, the FGR fetuses were subdivided into normal ≤95th centile) and abnormal (>95th centile). Neurosonography was performed at 33-44 weeks of gestations to assess CC and CV lengths and the depth of Sylvian fissure (SF), parieto-occipital (POF) and calcarine fissures (CF). Neurosonographic variables were normalized for fetal head circumference size.

RESULTS

The study cohort included 60 fetuses with late FGR, 39 with normal UtA PI and 21 with abnormal PI values. The latter group showed significant differences in CC (median (interquartile range) normal 35.9 (28.49-45.53) vs abnormal UtA PI 25.31(19.76-35.13) mm; p < 0.0022), CV (normal 25.78 (18.19-29.35) abnormal UtA PI 17.03 (14.07-24.16)mm; p = 0.0067); SF (normal 10.58 (8.99-11.97)vs abnormal UtA PI 7.44 (6.23-8.46) mm; p < 0.0001), POF (normal 6.85 (6.35-8.14) vs abnormal UtA PI 4.82 (3.46-7.75) mm; p < = 0.0184) and CF (normal 04.157 (2.85-5.41) vs abnormal UtA PI 2.33 (2.49-4.01)); p < 0.0382).

CONCLUSIONS

Late onset FGR fetuses with abnormal UtA PI showed shorter CC and CV length and delayed cortical development compared to those with normal uterine PI. These findings support the existence of a link between abnormal brain development and changes in utero placental circulation.

Fetal brain development in pregnancies complicated by gestational diabetes mellitus

OBJECTIVES

Gestational diabetes mellitus (GDM) carries an increased risk of neurocognitive impairment in offsprings. However, the contribution of maternal hyperglycemia in affecting fetal brain development is not fully elucidated yet. The aim of this study was to evaluate fetal brain and sulci development in pregnancies complicated by GDM.

METHODS

Prospective observational study including 100 singleton pregnancies complicated by GDM and 100 matched controls. All fetuses underwent neurosonography at 29-34 weeks of gestation, including the assessment of the length of the corpus callosum (CC), cerebellar vermis (CV), Sylvian (SF), parieto-occipital (POF) and calcarine fissures (CF). Sub-group analysis according to the specific treatment regimen adopted (n 67 diet vs. 33 insulin therapy) was also performed.

RESULTS

Fetuses from mothers with GDM under insulin therapy had a smaller CC (35.54 mm) compared to both controls (40 mm; p<0.001) and women with GDM under diet (39.26 mm; p=0.022) while there was no difference in the HC between the groups. Likewise, when corrected for HC, CV depth was smaller in fetuses with GDM both under insulin therapy (7.03 mm) and diet (7.05 mm,) compared to controls (7.36 mm; p=0.013). Finally, when assessing the sulci development of the brain SF (p≤0.0001), POF (p≤0.0001) and CF (p≤0.0001) were significantly smaller in fetuses with maternal GDM. Post-hoc analysis showed that fetuses of GDM mothers requiring insulin therapy had significantly lower values of SF (p=0.032), POF (p=0.016) and CF (p=0.001).

CONCLUSIONS

Pregnancies complicated by GDM showed a peculiar pattern of fetal brain growth and cortical development and these changes, which are more evident in those requiring insulin supplementation.

Effects of gender on fetal cortical development: a secondary analysis of a prospective cross-sectional study

OBJECTIVES

The primary objective was to evaluate the effects of fetal sex on fetal cortical development in low-risk pregnancies. Secondary objective was the evaluate the impact of gestational age.

METHODS

This was a secondary analysis of a prospective cross-sectional study on low-risk fetuses undergoing fetal neurosonography between 19 and 34 weeks of gestation. The depth of Sylvian Fissure (SF), Parieto Occipital Fissure (POF) and Calcarine Fissure (CF) were evaluated and related to fetal sex. Neurosonographic variables were normalized for fetal head circumference and expressed as multiple of the median (MoM).

RESULTS

A total of 344 fetuses were considered (173 male, 171 female). The baseline characteristic of the two groups were similar except a higher birthweight present in male fetuses (p=0.044). The depth SF (p=0.023) CF (p=0.014) and POF (p=0.046) showed significantly higher values in male fetuses when all the gestational age range was considered. However, when data were controlled for gestational age, these differences resulted significant only after 28 weeks.

CONCLUSIONS

Differences in cortical development related to gender occur after 28 weeks of gestation with an increase depth of SF, POF and CF in male fetuses.

Midline structures and cortical development in fetuses with late growth restriction according to Doppler status: prospective study

OBJECTIVE

Fetuses with late growth restriction (FGR) have a higher risk of sub-optimal neurocognitive performance after birth. Previous studies have reported that impaired brain and cortical development can start in utero. The primary aim of this study was to report midline structures and cortical development in fetuses with late growth restriction according to its severity; the secondary aim was to elucidate whether the severity of FGR, as defined by the presence of abnormal Doppler findings, plays a role in affecting brain growth and maturation.

METHODS

Prospective cross-sectional study including fetuses with late FGR undergoing neurosonography between 32 and 34 weeks of gestation. Midline structures (corpus callosum (CC) and cerebellar vermis (CV) length) and cortical development, including the depth of Sylvian (SF), parieto-occipital (POF) and calcarine (CF) were compared between FGR, small (SGA) and appropriate for gestational age (AGA) fetuses, defined upon the Delphi criteria. Sub-group analysis according to the severity of FGR (normal vs abnormal fetal Dopplers) was also performed. Univariate analysis was used to analyze the data.

RESULTS

52 FGR with normal, 60 with abnormal Dopplers, 64 SGA and 100 AGA fetuses were included in the analysis. SGA and FGR fetuses showed significant differences in absolute values of CC (median (interquartile range) control 43.47 (28.9-56.05), vs SGA 41.85 (27.82-51.79), vs FGR ND 38.54 (29.12-50.53), vs FGR AD 31.72 (23.8-40.19) K= 26.68; p<0.0001), CV (control 24.85 (17.55-29.21), SGA K=16.71; p=0.0008), SF (control 14.52 (10.65-16.76) vs SGA 12.71 (9.8-15.10) vs FGR ND 11.93 (9.12-13.43) VS FGR A 8.30 (6.72-10.33) K=75.82; p<0.0001), POF (control 8.56 (6.31-11.09) vs SGA 8.11 (5.58-10.43) vs FGR ND 7.81 (6.14-9.29) vs FGR AD 6.56 (4.22-7.99), K=45.06; p<0.0001) and CF ( control 9.27 (6.70-11.45) vs SGA 8.23 (5.67-10.65) vs FGR ND 7.68 (5.22-9.41) vs FGR AD 6.26 (4.48-7.19) K=46.14; p<0.0001) when compared to AGA controls with a progressive reduction across groups. When neurosonographic variables were corrected for fetal HC values, significant difference in the length of CC, SF, POF and CF but CV were observed only in FGR fetuses with abnormal Doppler when compared to AGA controls.

CONCLUSIONS

Late onset small fetuses showed shorter CC length and a delayed cortical development when compared to control. After controlling for HC size these differences remain significant only in FGR fetuses with abnormal Dopplers. These findings support the existence of a link between brain development and impaired placental function. This article is protected by copyright. All rights reserved.

Modeling fetal cortical development by quantile regression for gestational age and head circumference: a prospective cross sectional study

OBJECTIVES

To develop charts for fetal brain cortical structures following a proposed standardized methodology and using quantile regression.

METHODS

Prospective cross-sectional study including 344 low-risk singleton pregnancies between 19 and 34 weeks of gestation. The depth of Sylvian (SF), Parieto-occipital (POF) and Calcarine fissures (CF) were measured on ultrasound images using a standardized technique and their changes were evaluated by quantile regression as a function of gestational age (GA) interval or head circumference (HC).

RESULTS

The measurements of SF, POF and CF depth significantly increased with gestation. Linear models better described the changes of cortical variables with GA and HC. When the fit of sulci depth with GA and HC were compared, a close relationship was highlighted for the latter variable.

CONCLUSIONS

We provided prospective charts of fetal cortical development using quantile regression and following a strict standardized methodology These new charts may help in better identifying cases at higher risk of abnormal cortical neurodevelopment.

Modeling fetal cavum septum pellucidi width by quantile regression at 18-34 weeks of gestation: A prospective cross-sectional study

OBJECTIVE

Develop charts for cavum septum pellucidi (CSP) following a standardized methodology and using quantile regression. The secondary objective was to assess the influence of fetal gender on the generated reference curves.

METHODS

In a cross-sectional prospective study 453 low-risk singleton pregnancies were evaluated at a gestational age interval between 18 and 34 weeks. The width of CSP were measured on ultrasound images using a standardized technique and their changes were evaluated by quantile regression as a function of gestational age (GA) interval or head circumference (HC). Differences between sex were evaluated.

RESULTS

The measurement of CSP significantly increased with gestation and HC. Linear models better described the changes of CSP with GA and HC. The fits of CSP width with GA and HC were not significantly different. Male fetuses showed significantly higher CSP width when compared to female fetuses (u = 2.973; p = 0.005).

CONCLUSIONS

We generated prospective nomograms of fetal CSP development using quantile regression and following a strict standardized methodology. These new charts may be useful to better identify abnormal cases at higher risk of associated anomalies. Further our findings underline the potential effect of gender in developing fetal brain.

Evaluation of an artificial intelligent algorithm (Heartassist™) to automatically assess the quality of second trimester cardiac views: a prospective study

OBJECTIVES

The aim of this study was to evaluate the agreement between visual and automatic methods in assessing the adequacy of fetal cardiac views obtained during second trimester ultrasonographic examination.

METHODS

In a prospective observational study frames of the four-chamber view left and right outflow tracts, and three-vessel trachea view were obtained from 120 consecutive singleton low-risk women undergoing second trimester ultrasound at 19-23 weeks of gestation. For each frame, the quality assessment was performed by an expert sonographer and by an artificial intelligence software (Heartassist™). The Cohen's κ coefficient was used to evaluate the agreement rates between both techniques.

RESULTS

The number and percentage of images considered adequate visually by the expert or with Heartassist™ were similar with a percentage >87 % for all the cardiac views considered. The Cohen's κ coefficient values were for the four-chamber view 0.827 (95 % CI 0.662-0.992), 0.814 (95 % CI 0.638-0.990) for left ventricle outflow tract, 0.838 (95 % CI 0.683-0.992) and three vessel trachea view 0.866 (95 % CI 0.717-0.999), indicating a good agreement between the two techniques.

CONCLUSIONS

Heartassist™ allows to obtain the automatic evaluation of fetal cardiac views, reached the same accuracy of expert visual assessment and has the potential to be applied in the evaluation of fetal heart during second trimester ultrasonographic screening of fetal anomalies.

Validation of an automatic software in assessing fetal brain volume from three dimensional ultrasonographic volumes: Comparison with manual analysis

OBJECTIVE

This study was aimed to test the agreement between a manual and an automatic technique in measuring fetal brain volume (FBV) from three-dimensional (3D) fetal head datasets.

METHODS

FBV were acquired independently by two operators from low risk singleton pregnancies at a gestational age between 19 and 34 weeks. FBV measurements were obtained using an automatic software (Smart ICV™) and manually by Virtual Organ Computer-aided AnaLysis (VOCAL™). Intraclass correlation coefficient (ICC) were calculated to assess reliability, while bias and agreement were evaluate by examining Bland-Altman plots. The time spent in measuring volumes was calculated and values obtained compared.

RESULTS

Sixty-three volumes were considered for the study. In all the included volumes successful volume analysis were obtained with both techniques. Smart ICV™ showed a high intra-observer (0.996; 95% CI 0.994-0.998) and inter-observer (ICC 0.995; 95% CI 0.991-0.997). An excellent degree of reliability was found when the two techniques were compared (ICC 0.995; 95% CI 0.987-0.998). The time required to perform FBV was significantly lower for Smart ICV™ than VOCAL™ (8.2 ± 4.5 vs. 121.3 ± 19.0 s; p < 0.0001).

CONCLUSIONS

The measurement of FBV is feasible with both manual and automatic techniques. Smart ICV™ showed an excellent intra- and inter-observer reliability associated with a valuable agreement with volume measurements obtained manually with VOCAL™. Volumes may be measured significantly faster with smart ICV™ than manually and this automatic software has the potential to become the preferred methods for the assessment of FBV.