Three-Dimensional Volumetric Magnetic Resonance Imaging Detects Early Alterations of the Brain Growth in Fetuses With Congenital Heart Disease

Similarities and differences in cerebellar alterations between youth born preterm and youth born with congenital heart disease

Individuals born preterm (PT) or with complex congenital heart disease (CHD) present with comparable prevalence of developmental challenges and patterns of neonatal brain injury. Converging evidence also supports that cerebellar development is altered in PT and in CHD survivors. However, no study compared cerebellar integrity between these two groups. This study aims to assess total and regional cerebellar development between youth born PT or with CHD as compared to controls. Participants aged 16-27 years born before 33 weeks of gestational age or who underwent open-heart surgery for CHD during infancy and a group of healthy term-born controls, underwent a brain MRI. Cerebellums were segmented at the lobular level. Youth born PT or with CHD exhibited a comparable pattern of volume reduction affecting total, regional and lobular cerebellar volumes. After adjusting for total brain volume, no significant differences remained between CHD and controls. Only regions and lobules in the anterior cerebellum remained significantly smaller than controls in the youth born PT. Atypical cerebellar development is present in youth born PT and in youth with CHD. However, our results suggested that premature exposure to the extra-uterine environment alters cerebellar development selectively while the cumulative effect of CHD globally hinders brain development.

Alteration in Cortical Structure Mediating the Impact of Blood Oxygen-Carrying Capacity on Gross Motor Skills in Infants With Complex Congenital Heart Disease

Congenital heart disease (CHD) is the most common congenital anomaly, leading to an increased risk of neurodevelopmental abnormalities in many children with CHD. Understanding the neurological mechanisms behind these neurodevelopmental disorders is crucial for implementing early interventions and treatments. In this study, we recruited 83 infants aged 12-26.5 months with complex CHD, along with 86 healthy controls (HCs). We collected multimodal data to explore the abnormal patterns of cerebral cortex development and explored the complex interactions among blood oxygen-carrying capacity, cortical development, and gross motor skills. We found that, compared to healthy infants, those with complex CHD exhibit significant reductions in cortical surface area development, particularly in the default mode network. Most of these developmentally abnormal brain regions are significantly correlated with the blood oxygen-carrying capacity and gross motor skills of infants with CHD. Additionally, we further discovered that the blood oxygen-carrying capacity of infants with CHD can indirectly predict their gross motor skills through cortical structures, with the left middle temporal area and left inferior temporal area showing the greatest mediation effects. This study identified biomarkers for neurodevelopmental disorders and highlighted blood oxygen-carrying capacity as an indicator of motor development risk, offering new insights for the clinical management CHD.

Preoperative autonomic failure in neonates with critical congenital heart disease

BACKGROUND

Neonates with critical congenital heart disease (cCHD) undergo a complicated transition to ex-utero life. However, continuous monitoring of autonomic tone using heart rate variability is currently lacking.

MATERIALS AND METHODS

We retrieved continuous electrocardiograms from the time of admission or from 10 days prior to surgery for neonates with dextro-transposition of the great arteries (d-TGA) and hypoplastic left heart syndrome (HLHS). Beat-to-beat intervals (RRi) were calculated and divided into 10-min epochs. Spectral metrics, including low-frequency (LF) and high-frequency (HF) powers, as well as detrended fluctuation analysis metrics (αS, αL, RMSS, and RMSL), were computed for RRi within each epoch and averaged over 24 h. The relationship between RRi metrics and time to surgery was analyzed using linear mixed-effects models, adjusting for prenatal and postnatal factors.

RESULTS

The study included 10 neonates with HLHS and 23 with d-TGA. RRi metrics were available for 110 days. In the unadjusted models, LF power (Estimate: -4.4×10-3, P = 0.02), HF power (-4.1 x 10-2, 5 x 10-5), RMSS(-3.7 x 10-4, 8.7 x 10-3), and RMSL(-1.4× 10-3, 0.02) were all negatively associated with time to surgery, with HF power showing the strongest association. After adjusting for covariates, HF power retained its significant negative association with time (-0.04, P = 0.03). The cCHD diagnosis did not significantly influence RRi metrics.

CONCLUSIONS

In neonates with cCHD, there is a progressive decline in autonomic function leading up to surgery. RRi metrics may serve as valuable indicators of deteriorating physiology in these patients.

Prenatal MR Diagnosis of Total Anomalous Pulmonary Venous Connection and Related Brain Growth Changes

BACKGROUND

Prenatal diagnosis of total anomalous pulmonary venous connection (TAPVC) is challenging, and little is known about how it affects brain development.

PURPOSE

To evaluate the utility of fetal MRI to diagnose TAPVC and related brain growth changes.

STUDY TYPE

Retrospective case-control study.

POPULATION

Twenty-one fetuses (23.0 to 30.8 weeks, mean 26.4 weeks) with pre-natal MRI diagnosis of TAPVC. Post-natal images and surgery were available in 18 fetuses. Brain volumes in TAPVC fetuses were compared with age and sex matched 100 cases of normal controls and 38 fetuses with tetralogy of Fallot (TOF).

SEQUENCE

Single shot turbo spin echo sequence for evaluating fetal brain, and steady-state free precession (SSFP) sequence for evaluating fetal cardiovascular structures at 1.5 T.

ASSESSMENT

TAPVC type was determined by visualizing the drainage of the common pulmonary vein and dilated coronary sinus: supracardiac, intracardiac and infracardiac. The fetal pulmonary edema was evaluated, and fetal brain volumes were measured using automatic segmentation.

STATISTICAL TESTS

One-way analysis of variance and post hoc least square difference tests to evaluate differences in variables between TAPVC, TOF and control groups. A P value <0.05 was considered significant.

RESULTS

Of the 21 cases of TAPVC, 10 (47.6%) were identified as supracardiac, 8 (38.1%) as intracardiac, and 3 (14.3%) as infracardiac. Eighteen cases were confirmed by postnatal imaging and surgery; the remaining three cases had no confirmation. Six cases were associated with other cardiovascular abnormalities. Key MRI features of fetal TAPVC included a dilated coronary sinus and vertical vein. Fetal pulmonary edema was seen in six cases. Compared to controls, TAPVC fetuses had lower cerebellum and brainstem volumes and higher e-CSF, while had larger subcortical brain tissue, cerebellum, brainstem, e-CSF, and intracranial cavity volumes than those of TOF cases.

DATA CONCLUSION

Fetal MRI may be a useful modality for evaluating fetal TAPVC and altered brain development.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 3.

Lung volumes are increased in fetuses with transposition of the great arteries on intrauterine MRI

Fetal brain size is decreased in some children with complex CHDs, and the distribution of blood and accompanying oxygen and nutrients is regionally skewed from early fetal life dependent on the CHD. In transposition of the great arteries, deoxygenated blood preferentially runs to the brain, whereas the more oxygenated blood is directed towards the lungs and the abdomen. Knowledge of whether this impacts intrauterine organ development is limited. We investigated lung, liver, and total intracranial volume in fetuses with transposition of the great arteries using MRI.Eight fetuses with dextro-transposition and without concomitant disease or chromosomal abnormalities and 42 fetuses without CHD or other known diseases were scanned once or twice at gestational age 30 through 39 weeks. The MRI scans were conducted on a 1.5T system, using a 2D balanced steady-state free precession sequence. Slices acquired covered the entire fetus, slice thickness was 10 mm, pixel size 1.5 × 1.5 mm, and scan duration was 30 sec.The mean lung z score was significantly larger in fetuses with transposition compared with those without a CHD; mean difference is 1.24, 95% CI:(0.59;1.89), p < 0.001. The lung size, corrected for estimated fetal weight, was larger than in the fetuses without transposition; mean difference is 8.1 cm3/kg, 95% CI:(2.5;13.7 cm3/kg), p = 0.004.In summary, fetuses with dextro-transposition of the great arteries had both absolute and relatively larger lung volumes than those without CHD. No differences were seen in liver and total intracranial volume. Despite the small number of cases, the results are interesting and warrant further investigation.

[Research progress on neurodevelopmental disorders associated with congenital heart disease]

The incidence and disability rate of neurodevelopmental disorders in children are high, making it a significant public health issue affecting children's health globally. Neurodevelopmental disorders are particularly common in children with congenital heart disease (CHD), with clinical characteristics varying by type of CHD, surgical approach, age stage, and the presence of different complications or comorbidities. In recent years, based on the intervention model of "early diagnosis and early treatment," foreign studies have begun to explore new techniques for preventive early intervention in high-risk children with neurodevelopmental disorders, achieving promising results. This paper reviews the clinical characteristics of neurodevelopmental disorders associated with CHD, aiming to provide a theoretical basis for implementing new preventive early intervention techniques for children with CHD, thereby further reducing the incidence of neurodevelopmental disorders associated with CHD.

Structural Covariance Networks in the Fetal Brain Reveal Altered Neurodevelopment for Specific Subtypes of Congenital Heart Disease

BACKGROUND

Altered structural brain development has been identified in fetuses with congenital heart disease (CHD), suggesting that the neurodevelopmental impairment observed later in life might originate in utero. There are many interacting factors that may perturb neurodevelopment during the fetal period and manifest as structural brain alterations, such as altered cerebral substrate delivery and aberrant fetal hemodynamics.

METHODS AND RESULTS

We extracted structural covariance networks from the log Jacobian determinants of 435 in utero T2 weighted image magnetic resonance imaging scans, (n=67 controls, 368 with CHD) acquired during the third trimester. We fit general linear models to test whether age, sex, expected cerebral substrate delivery, and CHD diagnosis were significant predictors of structural covariance. We identified significant effects of age, sex, cerebral substrate delivery, and specific CHD diagnosis across a variety of structural covariance networks, including primary motor and sensory cortices, cerebellar regions, frontal cortex, extra-axial cerebrospinal fluid, thalamus, brainstem, and insula, consistent with widespread coordinated aberrant maturation of specific brain regions over the third trimester.

CONCLUSIONS

Structural covariance networks offer a sensitive, data-driven approach to explore whole-brain structural changes without anatomical priors. We used them to stratify a heterogenous patient cohort with CHD, highlighting similarities and differences between diagnoses during fetal neurodevelopment. Although there was a clear effect of abnormal fetal hemodynamics on structural brain maturation, our results suggest that this alone does not explain all the variation in brain development between individuals with CHD.

MRI in the prenatal genetic diagnosis and intrauterine treatment of fetal congenital cystic adenoma of the lung

OBJECTIVE

To investigate the value of magnetic resonance examination technique for prenatal genetic diagnosis and clinical intrauterine treatment of fetal congenital cystic adenoma (CCAM) of the lung.

METHODS

A retrospective analysis was conducted on 108 pregnant women admitted to a certain hospital from January 2016 to January 2022 for pre natal examination and consultation on eugenics. The selected pregnant women were aged 20-40 and had a gestational age of 17-36 weeks. Ultrasound and MRI examinations were performed on 108 pregnant women who met the inclusion criteria. Follow-up and investigation were conducted on the fetus after being diagnosed with CCAM. To analyze the results of prenatal genetic diagnosis, chromosome microarray analysis (CMA) was used to analyze samples with pathogenic Copy Number Variants (CNV) and identify pathogenic genes. Finally, the imaging diagnosis results obtained through statistical software were analyzed, and the correlation between pathogenic genes and CCAM, as well as the clinical application value of MRI in fetal intrauterine treatment was explored.

RESULTS

Among all cases, 68 fetuses were diagnosed with CCAM through ultrasound examination; 71 fetuses were diagnosed with CCAM through MRI examination. A total of 74 samples were confirmed as CCAM by autopsy and neonatal CT. The sensitivity, specificity, and accuracy of MRI in diagnosing fetal congenital CCAM were higher than those of ultrasound examination. The expression of CCAM was positively correlated with DUSP22, PRSS1, and SHOX, with all R values greater than 0.8. The clinical decision curve showed that when the probability of fetal CCAM was less than 0.03, the prenatal genetic diagnostic model of MRI was not applicable; But when the probability of fetal CCAM was higher than 0.05, the auxiliary intrauterine treatment effect that MRI diagnostic methods achieved was significantly better than conventional diagnosis.

CONCLUSION

MRI is significantly better than ultrasound in the diagnosis of CCAM, which can effectively improve the sensitivity of diagnosis and provide accurate information for the eugenics of pregnant women, and has high clinical application value.

Total and Regional Brain Volumes in Fetuses With Congenital Heart Disease

BACKGROUND

Congenital heart disease (CHD) is common and is associated with impaired early brain development and neurodevelopmental outcomes, yet the exact mechanisms underlying these associations are unclear.

PURPOSE

To utilize MRI data from a cohort of fetuses with CHD as well as typically developing fetuses to test the hypothesis that expected cerebral substrate delivery is associated with total and regional fetal brain volumes.

STUDY TYPE

Retrospective case-control study.

POPULATION

Three hundred eighty fetuses (188 male), comprising 45 healthy controls and 335 with isolated CHD, scanned between 29 and 37 weeks gestation. Fetuses with CHD were assigned into one of four groups based on expected cerebral substrate delivery.

FIELD STRENGTH/SEQUENCE

T2-weighted single-shot fast-spin-echo sequences and a balanced steady-state free precession gradient echo sequence were obtained on a 1.5 T scanner.

ASSESSMENT

Images were motion-corrected and reconstructed using an automated slice-to-volume registration reconstruction technique, before undergoing segmentation using an automated pipeline and convolutional neural network that had undergone semi-supervised training. Differences in total, regional brain (cortical gray matter, white matter, deep gray matter, cerebellum, and brainstem) and brain:body volumes were compared between groups.

STATISTICAL TESTS

ANOVA was used to test for differences in brain volumes between groups, after accounting for sex and gestational age at scan. PFDR-values <0.05 were considered statistically significant.

RESULTS

Total and regional brain volumes were smaller in fetuses where cerebral substrate delivery is reduced. No significant differences were observed in total or regional brain volumes between control fetuses and fetuses with CHD but normal cerebral substrate delivery (all PFDR > 0.12). Severely reduced cerebral substrate delivery is associated with lower brain:body volume ratios.

DATA CONCLUSION

Total and regional brain volumes are smaller in fetuses with CHD where there is a reduction in cerebral substrate delivery, but not in those where cerebral substrate delivery is expected to be normal.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 3.

Biometric magnetic resonance imaging analysis of fetal brain development in Down syndrome

OBJECTIVES

To assess brain development in living fetuses with Down syndrome (DS) by biometric measurements on fetal brain magnetic resonance images (MRI).

METHODS

We scanned 10 MRIs of fetuses with confirmed trisomy 21 at birth and 12 control fetal MRIs without any detected anomalies. Fetal brain MRIs were analyzed using 14 fetal brain and skull biometric parameters. We compared measures between DS and controls in both raw MRIs and motion-corrected and anterior-posterior commissure-aligned images.

RESULTS

In the reconstructed images, the measured values of the height of the cerebellar vermis (HV) and anteroposterior diameter of the cerebellar vermis (APDV) were significantly smaller, and the anteroposterior diameter of the fourth ventricle (APDF) was significantly larger in fetuses with DS than controls. In the raw MRIs, the measured values of the right lateral ventricle were significantly larger in fetuses with DS than in controls. Logistic regression analyses revealed that a new parameter, the cerebellar-to-fourth-ventricle ratio (i.e., (APDV * Height of the vermis)/APDF), was significantly smaller in fetuses with DS than controls and was the most predictive to distinguish between fetuses with DS and controls.

CONCLUSIONS

The study revealed that fetuses with DS have smaller cerebellums and larger fourth ventricles compared to the controls.

Fetal MRI of the heart and brain in congenital heart disease

Antenatal assessment of congenital heart disease and associated anomalies by ultrasound has improved perinatal care. Fetal cardiovascular MRI and fetal brain MRI are rapidly evolving for fetal diagnostic testing of congenital heart disease. We give an overview on the use of fetal cardiovascular MRI and fetal brain MRI in congenital heart disease, focusing on the current applications and diagnostic yield of structural and functional imaging during pregnancy. Fetal cardiovascular MRI in congenital heart disease is a promising supplementary imaging method to echocardiography for the diagnosis of antenatal congenital heart disease in weeks 30-40 of pregnancy. Concomitant fetal brain MRI is superior to brain ultrasound to show the complex relationship between fetal haemodynamics in congenital heart disease and brain development.

Harnessing the Power of Advanced Fetal Neuroimaging to Understand In Utero Footprints for Later Neuropsychiatric Disorders

Adverse intrauterine events may profoundly impact fetal risk for future adult diseases. The mechanisms underlying this increased vulnerability are complex and remain poorly understood. Contemporary advances in fetal magnetic resonance imaging (MRI) have provided clinicians and scientists with unprecedented access to in vivo human fetal brain development to begin to identify emerging endophenotypes of neuropsychiatric disorders such as autism spectrum disorder, attention-deficit/hyperactivity disorder, and schizophrenia. In this review, we discuss salient findings of normal fetal neurodevelopment from studies using advanced, multimodal MRI that have provided unparalleled characterization of in utero prenatal brain morphology, metabolism, microstructure, and functional connectivity. We appraise the clinical utility of these normative data in identifying high-risk fetuses before birth. We highlight available studies that have investigated the predictive validity of advanced prenatal brain MRI findings and long-term neurodevelopmental outcomes. We then discuss how ex utero quantitative MRI findings can inform in utero investigations toward the pursuit of early biomarkers of risk. Lastly, we explore future opportunities to advance our understanding of the prenatal origins of neuropsychiatric disorders using precision fetal imaging.

Brainstem and cerebellar volumes at magnetic resonance imaging are smaller in fetuses with congenital heart disease

BACKGROUND

Congenital heart disease is associated with an increased risk of smaller brain volumes and structural brain damage, and impaired growth of supratentorial brain structures in utero has been linked to poor neurodevelopmental outcomes. However, little is known on brainstem and cerebellar volumes in fetuses with congenital heart disease. Moreover, it is not clear whether impaired infratentorial growth, if present, is associated with only certain types of fetal cardiac defects or with supratentorial brain growth, and whether altered biometry is already present before the third trimester.

OBJECTIVE

This study aimed to investigate brainstem and cerebellar volumes in fetuses with congenital heart disease and to compare them to infratentorial brain volumes in fetuses with normal hearts. Secondarily, the study aimed to identify associations between infratentorial brain biometry and the type of cardiac defects, supratentorial brain volumes, and gestational age.

STUDY DESIGN

In this retrospective case-control study, 141 magnetic resonance imaging studies of 135 fetuses with congenital heart disease and 141 magnetic resonance imaging studies of 125 controls with normal hearts at 20 to 37 gestational weeks (median, 25 weeks) were evaluated. All cases and controls had normal birthweight and no evidence of structural brain disease or genetic syndrome. Six types of congenital heart disease were included: tetralogy of Fallot (n=32); double-outlet right ventricle (n=22); transposition of the great arteries (n=27); aortic obstruction (n=24); hypoplastic left heart syndrome (n=22); and hypoplastic right heart syndrome (n=14). First, brainstem and cerebellar volumes of each fetus were segmented and compared between cases and controls. In addition, transverse cerebellar diameters, vermian areas, and supratentorial brain and cerebrospinal fluid volumes were quantified and differences assessed between cases and controls. Volumetric differences were further analyzed according to types of cardiac defects and supratentorial brain volumes. Finally, volume ratios were created for each brain structure ([volume in fetus with congenital heart disease/respective volume in control fetus] × 100) and correlated to gestational age.

RESULTS

Brainstem (cases, 2.1 cm³ vs controls, 2.4 cm³; P<.001) and cerebellar (cases, 3.2 cm³ vs controls, 3.4 cm³; P<.001) volumes were smaller in fetuses with congenital heart disease than in controls, whereas transverse cerebellar diameters (P=.681) and vermian areas (P=.947) did not differ between groups. Brainstem and cerebellar volumes differed between types of cardiac defects. Overall, the volume ratio of cases to controls was 80.8% for the brainstem, 90.5% for the cerebellum, and 90.1% for the supratentorial brain. Fetuses with tetralogy of Fallot and transposition of the great arteries were most severely affected by total brain volume reduction. Gestational age had no effect on volume ratios.

CONCLUSION

The volume of the infratentorial brain, which contains structures considered crucial to brain function, is significantly smaller in fetuses with congenital heart disease than in controls from midgestation onward. These findings suggest that impaired growth of both supra- and infratentorial brain structures in fetuses with congenital heart disease occurs in the second trimester. Further research is needed to elucidate associations between fetal brain volumes and neurodevelopmental outcomes in congenital heart disease.

Reference biometry of foetal brain by prenatal MRI and the distribution of measurements in foetuses with ventricular septal defect

OBJECTIVE

To provide the reference biometric measurements of the normal foetal brain by prenatal MRI and describe the distribution of measurements in the foetuses with ventricular septal defect (VSD).

METHODS

This retrospective study analysed the biometric measurements of 218 foetuses between 18 - 37 gestational weeks with normal MRI findings from July 2014 to August 2019, as well as 18 foetuses with VSD. The measurements included fronto-occipital diameter (FOD), biparietal diameter (BPD), and transverse cerebellar diameter (TCD). All the prenatal MRI examinations have been taken on the same 1.5 T MR unit with a standard protocol of the foetal brain. All the linear measurements of the foetal brain were obtained on the T2-weighted imaging. The distribution of measurements in 18 foetuses with VSD was plotted on centile curves.

RESULTS

The reference data were presented in mean, standard deviation, 95% predicted confidence intervals, and the 3rd, 10th, 25th, 50th, 75th, 90th, 97th centiles at each gestational age. The value of TCD in 56% (10/18 cases) foetuses with VSD was lower than the 3rd centile, and the rate for FOD and BPD was 33% (6/18 cases) and 22% (4/18 cases) separately. On the curves, most VSD cases with measurements lower than the 3rd centile were in relatively early gestational stage (≤28 weeks).

CONCLUSIONS

We have presented reference linear biometry of the foetal brain by prenatal MRI from 18 to 37 gestational weeks, which could help us to interpret and monitor the brain development for foetuses with VSD and other congenital heart diseases.Key messages:We have presented reference linear biometry of the foetal brain by prenatal MRI from 18 to 37 gestational weeks in multiple statistical methods: mean and standard deviation; 95% predicted confidence intervals and the 3rd, 10th, 25th, 50th, 75th, 90th, 97th centiles.Our data showed that the involvement of the brain in VSD may be not globally, but regionally, and the cerebellum may be more possible to be involved.We speculated that the earlier the VSD diagnosed the worse the brain involved, which might suggest a poor outcome and necessary follow-up.

Magnetic Resonance Imaging Segmentation via Weighted Level Set Model Based on Local Kernel Metric and Spatial Constraint

Magnetic resonance imaging (MRI) segmentation is a fundamental and significant task since it can guide subsequent clinic diagnosis and treatment. However, images are often corrupted by defects such as low-contrast, noise, intensity inhomogeneity, and so on. Therefore, a weighted level set model (WLSM) is proposed in this study to segment inhomogeneous intensity MRI destroyed by noise and weak boundaries. First, in order to segment the intertwined regions of brain tissue accurately, a weighted neighborhood information measure scheme based on local multi information and kernel function is designed. Then, the membership function of fuzzy c-means clustering is used as the spatial constraint of level set model to overcome the sensitivity of level set to initialization, and the evolution of level set function can be adaptively changed according to different tissue information. Finally, the distance regularization term in level set function is replaced by a double potential function to ensure the stability of the energy function in the evolution process. Both real and synthetic MRI images can show the effectiveness and performance of WLSM. In addition, compared with several state-of-the-art models, segmentation accuracy and Jaccard similarity coefficient obtained by WLSM are increased by 0.0586, 0.0362 and 0.1087, 0.0703, respectively.