Brain Anomalies Research Articles

Role of Mri in Characterization of Congenital Malformations of Brain in A Tertiary Care Centre-A Retrospective Study

Background: Congenital brain anomalies are rare among the congenital anomalies of various organ systems. It is crucial to recognise these disorders as soon as possible because of the extensive neurological deficiency and negative consequences they can cause. Neuroimaging is a reliable way to accurately diagnose the majority of congenital brain abnormalities. There aren't enough statistics available in developing countries like India about the frequency and types of brain abnormalities. The purpose of this study is to examine the prevalence and range of frequently occurring congenital brain abnormalities. Objective: To study the whole spectrum of all substantial and frequently occurring congenital abnormalities as well as the proportional distribution of the various brain malformations in a tertiary care centre. Methods and materials: The study was conducted at Department of Radio-Diagnosis, Medical College Kolkata from 1st September 2022 to 31st August 2023. All MRI brain examinations at our hospital over a period of one year were retrospectively reviewed and analysed by sex, age at presentation, type of congenital cerebral malformation, and other associated congenital cerebral malformations. Results: This study included 24 patients. The total number of brain malformations identified in these patients was 33. The age of patients at first MRI imaging ranged from 5 days to 16 years. There were 14 males and 10 females. The most common malformations were corpus callosum dysgenesis (24%), Heterotropia (15%) and Lissencephaly (12%). Seven patients (29.1%) had more than one congenital brain malformation. Conclusion: The variety and complexity of congenital brain abnormalities is remarkable. The correct diagnosis is essential for the best care of these unfortunate conditions, and MRI plays a significant role in this process. Identification of distinctive neuroimaging findings of various congenital brain anomalies are immensely helpful in diagnosing the anomalies and further management.

Expanding the phenotypic spectrum of NOTCH1 variants: clinical manifestations in families with congenital heart disease.

Pathogenic variants in NOTCH1 are associated with non-syndromic congenital heart disease (CHD) and Adams-Oliver syndrome (AOS). The clinical presentation of individuals with damaging NOTCH1 variants is characterized by variable expressivity and incomplete penetrance; however, data on systematic phenotypic characterization are limited. We report the genotype and phenotype of a cohort of 33 individuals (20 females, 13 males; median age 23.4 years, range 2.5-68.3 years) from 11 families with causative NOTCH1 variants (9 inherited, 2 de novo; 9 novel), ascertained from a proband with CHD. We describe the cardiac and extracardiac anomalies identified in these 33 individuals, only four of whom met criteria for AOS. The most common CHD identified was tetralogy of Fallot, though various left- and right-sided lesions and septal defects were also present. Extracardiac anomalies identified include cutis aplasia (5/33), cutaneous vascular anomalies (7/33), vascular anomalies of the central nervous system (2/10), Poland anomaly (1/33), pulmonary hypertension (2/33), and structural brain anomalies (3/14). Identification of these findings in a cardiac proband cohort supports NOTCH1-associated CHD and NOTCH1-associated AOS lying on a phenotypic continuum. Our findings also support (1) Broad indications for NOTCH1 molecular testing (any familial CHD, simplex tetralogy of Fallot or hypoplastic left heart); (2) Cascade testing in all at-risk relatives; and (3) A thorough physical exam, in addition to cardiac, brain (structural and vascular), abdominal, and ophthalmologic imaging, in all gene-positive individuals. This information is important for guiding the medical management of these individuals, particularly given the high prevalence of NOTCH1 variants in the CHD population.

Deep-Learning-Based Automated Anomaly Detection of EEGs in Intensive Care Units.

An intensive care unit (ICU) is a special ward in the hospital for patients who require intensive care. It is equipped with many instruments monitoring patients' vital signs and supported by the medical staff. However, continuous monitoring demands a massive workload of medical care. To ease the burden, we aim to develop an automatic detection model to monitor when brain anomalies occur. In this study, we focus on electroencephalography (EEG), which monitors the brain electroactivity of patients continuously. It is mainly for the diagnosis of brain malfunction. We propose the gated-recurrent-unit-based (GRU-based) model for detecting brain anomalies; it predicts whether the spike or sharp wave happens within a short time window. Based on the banana montage setting, the proposed model exploits characteristics of multiple channels simultaneously to detect anomalies. It is trained, validated, and tested on separated EEG data and achieves more than 90% testing performance on sensitivity, specificity, and balanced accuracy. The proposed anomaly detection model detects the existence of a spike or sharp wave precisely; it will notify the ICU medical staff, who can provide immediate follow-up treatment. Consequently, it can reduce the medical workload in the ICU significantly.

GNB1 and obesity: Evidence for a correlation between haploinsufficiency and syndromic obesity.

Most patients with GNB1 encephalopathy have developmental delay and/or intellectual disability, brain anomalies and seizures. Recently, two cases with GNB1 encephalopathy caused by haploinsufficiency have been reported that also show a Prader-Willi-like phenotype of childhood hypotonia and severe obesity. Here we present three new cases from our expert centre for genetic obesity in which GNB1 truncating and splice variants, probably leading to haploinsufficiency, were identified. They all have obesity, hyperphagia and intellectual deficit. The clinical cases and their weight courses are presented, together with a review of all 68 published cases with GNB1 encephalopathy. Information on weight was not mentioned in most of these articles, so we contacted authors for additional clinical information on weight status and hyperphagia. Of the 42 patients whose weight status we could determine, obesity was present in 8 patients (19%). Obesity is significantly over-represented in the group with truncating and splicing variants. In this group, we see an obesity prevalence of 75%. Since GNB1 has been linked to several key genes in the hypothalamic leptin-melanocortin pathway, which regulates satiety and energy expenditure, our data support the potential association between GNB1 haploinsufficiency and genetic obesity. We also suggest GNB1 is a candidate gene for the known obesity phenotype of the 1p36 microdeletion syndrome given this chromosomal region includes the GNB1 gene. Knowledge of an additional obesity phenotype is important for prognosis, early interventions against obesity and awareness when prescribing weight-inducing medication.

Case Report: Dichorionic-Diamniotic Twin Pregnancy Complicated by a Migrational Anomaly Mimicking a Brain Neoplasm

Background Fetal brain anomalies have a wide differential diagnosis including: (1) congenital genetic and vascular disorders; (2) acquired causes such as infection and hypoxic-ischemic injury; and rarely (3) neoplasm. Fetal brain anomalies are also infrequently seen. Consequently, there is limited literature describing methods of distinguishing these conditions, barring the presence of the most characteristic findings on imaging. Objective The purpose of this report is to describe the critical parts of our workup that helped us distinguish a fetal brain migrational disorder from a neoplasm. Study Design Case report of a single patient seen at Tripler Army Medical Center and Children’s Hospital of Los Angeles Case Summary (Results) 24-year-old gravida 1 with a dichorionic-diamniotic twin pregnancy was found to have an intracranial abnormality in Twin A on a transabdominal ultrasound performed at 16w1d gestation. Serial prenatal ultrasounds and complementary fetal magnetic resonance imaging (MRI) studies were performed to distinguish a possible fetal brain tumor from a migrational disorder. Fetal MRIs performed at 19w1d and 23w0d demonstrated a mass-like region increasing in size which was interpreted as highly suggestive of an enlarging fetal brain tumor. Ultimately, additional radiologic findings of fluid filled clefts and polymicrogyria visualized at 32 weeks led to a definitive diagnosis of a fetal migrational disorder. Conclusion Features used to diagnose fetal brain anomalies are often nonspecific and develop throughout a gestation. Most of these diagnoses require multiple imaging studies carried out over time to identify key features, and characteristic key features often do not present until very late in a gestation. The differential diagnosis of a dysplastic appearing mass-like region growing in size throughout a pregnancy should include fetal migrational disorders.

Developmental dyslexia susceptibility genes DNAAF4, DCDC2, and NRSN1 are associated with brain function in fluently reading adolescents and young adults.

Reading skills and developmental dyslexia, characterized by difficulties in developing reading skills, have been associated with brain anomalies within the language network. Genetic factors contribute to developmental dyslexia risk, but the mechanisms by which these genes influence reading skills remain unclear. In this preregistered study (https://osf.io/7sehx), we explored if developmental dyslexia susceptibility genes DNAAF4, DCDC2, NRSN1, and KIAA0319 are associated with brain function in fluently reading adolescents and young adults. Functional MRI and task performance data were collected during tasks involving written and spoken sentence processing, and DNA sequence variants of developmental dyslexia susceptibility genes previously associated with brain structure anomalies were genotyped. The results revealed that variation in DNAAF4, DCDC2, and NRSN1 is associated with brain activity in key language regions: the left inferior frontal gyrus, middle temporal gyrus, and intraparietal sulcus. Furthermore, NRSN1 was associated with task performance, but KIAA0319 did not yield any significant associations. Our findings suggest that individuals with a genetic predisposition to developmental dyslexia may partly employ compensatory neural and behavioral mechanisms to maintain typical task performance. Our study highlights the relevance of these developmental dyslexia susceptibility genes in language-related brain function, even in individuals without developmental dyslexia, providing valuable insights into the genetic factors influencing language processing.

Further delineation of phenotype and genotype of Kenny-Caffey syndrome type 2 (phenotype and genotype of KCS type 2).

Kenny-Caffey syndrome type 2 (KCS2) is an extremely rare inherited disorder characterized by proportionate short stature, skeletal defects, ocular and dental abnormalities, and transient hypocalcemia. It is caused by variants in FAM111A gene. Diagnosis of KCS2 can be challenging because of its similarities to other syndromes, the absence of clear hallmarks and the deficient number of genetically confirmed cases. Here, we aimed to further delineate and summarize the genotype and phenotype of KCS2, in order to get a better understanding of this rare disorder, and promote early diagnosis and intervention. We present clinical and genetic characteristics of eight newly affected individuals with KCS2 from six families, including one family with three individuals found to be a father-to-daughter transmission, adding to the limited literature. Furthermore, we performed a review of genetically confirmed KCS2 cases in PubMed, MEDLINE and CNKI databases. There were six females and two males in our cohort. All the patients presented with short stature (100.0%). Clinical manifestations included ocular defects such as hypermetropia (5/8), dental problems such as defective dentition (3/8) and dental caries (3/8), skeletal and brain anomalies such as delayed closure of anterior fontanelle (6/8), cerebral calcification (3/8), cortical thickening (3/8) and medullary stenosis (4/8) of tubular bones. Endocrinologic abnormalities included hypoparathyroidism (5/8) and hypocalcemia (3/8). One male patient had micropenis and microorchidism. All cases harboured missense variants of FAM111A, and nucleotides c.1706 arose as a mutational hotspot, with seven individuals harbouring a c.1706G>A (p.Arg569His) variant, and one child harbouring a c.1531T>C (p.Tyr511His) variant. Literature review yielded a total of 46 patients from 20 papers. Data analysis showed that short stature, hypoparathyroidism and hypocalcemia, ocular and dental defects, skeletal features including cortical thickening and medullary stenosis of tubular bones, and seizures/spasms were present in more than 70% of the reported KCS2 cases. We provide detailed characteristics of the largest KCS2 group in China and present the first genetically confirmed instance of father-to-daughter transmission of KCS2. Our study confirms that Arg569His is the hot spot variant and summarizes the typical phenotypes of KCS2, which would help early diagnosis and intervention.

Perisylvian and Hippocampal Anomalies in Individuals With Pathogenic GRIN2A Variants.

Pathogenic variants in GRIN2A are associated with a spectrum of epilepsy-aphasia syndromes (EASs). Seizures as well as speech and language disorders occur frequently but vary widely in severity, both between individuals and across the life span. The link between this phenotypic spectrum and brain characteristics is unknown. Specifically, altered brain networks at the root of speech and language deficits remain to be identified. Patients with pathogenic variants in GRIN2A offer an opportunity to interrogate the impact of glutamate receptor dysfunction on brain development. We characterized brain anomalies in individuals with pathogenic GRIN2A variants and EASs, hypothesizing alterations in perisylvian speech-language regions and the striatum. We compared structural MRI data from 10 individuals (3 children and 7 adults, 3 female) with pathogenic GRIN2A variants with data from age-matched controls (N = 51 and N = 203 in a secondary analysis). We examined cortical thickness and volume in 4 a priori hypothesized speech and language regions (inferior frontal, precentral, supramarginal, and superior temporal) and across the whole brain. Subcortical structures (hippocampus, basal ganglia, thalamus) and the corpus callosum were also compared. Individuals with pathogenic GRIN2A variants showed increased thickness and volume in the posterior part of Broca's area (inferior frontal gyrus, pars opercularis). For thickness, the effects were bilateral but more pronounced in the left (large effect size, η2 = 0.37) than the right (η2 = 0.12) hemisphere. Both volume and thickness were also higher in the bilateral superior temporal region while the supramarginal region showed increased thickness only. Whole-brain analyses confirmed left-sided thickness increases in Broca's area, with additional increases in the occipital and superior frontal cortices bilaterally. Hippocampal volume was reduced in the left hemisphere. There were no age-dependent effects or corpus callosum group differences. Anomalies in perisylvian regions, with largest differences in Broca's area, suggest an altered development of classical speech-language networks in GRIN2A-related EAS. Left hippocampal reduction suggests a role for this structure in early speech and language development and is consistent with GRIN2A gene expression in that region. Overall, elucidating the neural correlates of EAS provides insights into the impact of GRIN2A dysfunction, opening avenues for targeted intervention in developmental syndromes with compromised speech-language development.

New insights into the clinical and molecular spectrum of the MADD-related neurodevelopmental disorder

Biallelic pathogenic variants in MADD lead to a very rare neurodevelopmental disorder which is phenotypically pleiotropic grossly ranging from severe neonatal hypotonia, failure to thrive, multiple organ dysfunction, and early lethality to a similar but milder phenotype with better survival. Here, we report 5 patients from 3 unrelated Egyptian families in whom 4 patients showed the severe end of the spectrum displaying neonatal respiratory distress, hypotonia and chronic diarrhea while one patient presented with the mild form displaying moderate intellectual disability and myopathy. In addition, we observed distal arthrogryposis and nonspecific structural brain anomalies in all our patients. Interestingly, cerebellar and brainstem hypoplasia were noted in one patient. Whole exome sequencing identified three novel homozygous variants in the MADD gene: two likely pathogenic [c.4321delC p.(Gln1441ArgfsTer46) and c.2620 C > T p.(Arg874Ter)] and one variant of uncertain significance (c.4307 G > A, p.Arg1436Gln). The variants segregated with the disease in all available family members. Our findings confirm that arthrogryposis, genital, cardiac and structural brain anomalies are manifestations of MADD which expand the spectrum of MADD-related neurodevelopmental disorder. Moreover, they further highlight the convergence of MADD variants on different organ systems leading to complex phenotypes.

A recurrent missense variant in the E3 ubiquitin ligase substrate recognition subunit FEM1B causes a rare syndromic neurodevelopmental disorder

PurposeFem1 homolog B (FEM1B) acts as a substrate recognition subunit for ubiquitin ligase complexes belonging to the CULLIN 2-based E3 family. Several biological functions have been proposed for FEM1B, including a structurally resolved function as a sensor for redox cell status by controlling mitochondrial activity, but its implication in human disease remains elusive. MethodsTo understand the involvement of FEM1B in human disease, we made use of Matchmaker exchange platforms to identify individuals with de novo variants in FEM1B and performed their clinical evaluation. We performed functional validation using primary neuronal cultures and in utero electroporation assays, as well as experiments on patient’s cells. ResultsFive individuals with a recurrent de novo missense variant in FEM1B were identified: NM_015322.5:c.377G>A NP_056137.1:p.(Arg126Gln) (FEM1BR126Q). Affected individuals shared a severe neurodevelopmental disorder with behavioral phenotypes and a variable set of malformations, including brain anomalies, clubfeet, skeletal abnormalities, and facial dysmorphism. Overexpression of the FEM1BR126Q variant but not FEM1B wild-type protein, during mouse brain development, resulted in delayed neuronal migration of the target cells. In addition, the individuals’ cells exhibited signs of oxidative stress and induction of type I interferon signaling. ConclusionOverall, our data indicate that p.(Arg126Gln) induces aberrant FEM1B activation, resulting in a gain-of-function mechanism associated with a severe syndromic developmental disorder in humans.

Exploring the phenotypic spectrum and osteopenia mechanisms in Yunis-Varón syndrome

PurposeBiallelic variants in FIG4 or VAC14 are associated with Yunis-Varón syndrome (YVS), which is characterized by multisystem involvement including skeletal findings, craniofacial dysmorphisms and central nervous system anomalies. Pathogenic variants in those same genes have also been associated with a predominantly neurological phenotype and with nonsyndromic conditions, such as Charcot-Marie-Tooth disease and amyotrophic lateral sclerosis. By describing 5 new cases of FIG4-associated YVS and reviewing the literature, we better delineate the clinical phenotype associated with loss of function of those genes. We also explore osteopenia mechanisms by assessing bone physiologic parameters in a mouse model. MethodsExome sequencing or Sanger sequencing was performed in 5 unrelated individuals. Bone histomorphometry was performed in Fig4plt/plt mice and compared with wild type. Relevant literature from the last 10 years was reviewed. ResultsAll individuals presented a phenotype overlapping the typical YVS and the brain anomalies and neurologic syndrome. Clinical features included developmental delay, structural brain malformations, and skeletal anomalies, such as osteopenia. Biallelic FIG4 variants were identified in each individual. In mice, bone histomorphometry parameters suggested that osteopenia might be secondary to reduced bone formation rather than increased bone degradation. ConclusionThis study contributes to a better understanding of the phenotypic variability caused by pathogenic variants in FIG4 or VAC14 and suggests an important overlap between previously described phenotypes. The brain anomalies and neurologic syndrome is likely in the same spectrum as classical YVS. Further studies are still needed to clarify the effects of partial loss-of-function (hypomorphic) variants and to identify genotype-phenotype correlations.

A Child with Facial Dysmorphism, Visual Impairment, and Congenital Brain Anomaly (Answers)

A Child with Facial Dysmorphism, Visual Impairment, and Congenital Brain Anomaly (Answers)

Differential alternative splicing analysis links variation in ZRSR2 to a novel type of oral-facial-digital syndrome

PurposeOral-facial-digital (OFD) syndromes are genetically heterogeneous developmental disorders, caused by pathogenic variants in genes involved in primary cilia formation and function. We identified a previously undescribed type of OFD with brain anomalies, ranging from alobar holoprosencephaly to pituitary anomalies, in 6 unrelated families. MethodsExome sequencing of affected probands was supplemented with alternative splicing analysis in patient and control lymphoblastoid and fibroblast cell lines, and primary cilia structure analysis in patient fibroblasts. ResultsIn 1 family with 2 affected males, we identified a germline variant in the last exon of ZRSR2, NM_005089.4:c.1211_1212del NP_005080.1:p.(Gly404GlufsTer23), whereas 7 affected males from 5 unrelated families were hemizygous for the ZRSR2 variant NM_005089.4:c.1207_1208del NP_005080.1:p.(Arg403GlyfsTer24), either occurring de novo or inherited in an X-linked recessive pattern. ZRSR2, located on chromosome Xp22.2, encodes a splicing factor of the minor spliceosome complex, which recognizes minor introns, representing 0.35% of human introns. Patient samples showed significant enrichment of minor intron retention. Among differentially spliced targets are ciliopathy-related genes, such as TMEM107 and CIBAR1. Primary fibroblasts containing the NM_005089.4:c.1207_1208del ZRSR2 variant had abnormally elongated cilia, confirming an association between defective U12-type intron splicing, OFD and abnormal primary cilia formation. ConclusionWe introduce a novel type of OFD associated with elongated cilia and differential splicing of minor intron-containing genes due to germline variation in ZRSR2.

Spondylocostal dysostosis: A rare case report

Spondylocostal dysostosis (SCD), also known as Jarcho Levin syndrome, is a rare congenital dysostosis characterized by multiple congenital vertebral and rib anomalies. The child usually presents with respiratory distress at birth with eventual development of short trunk dwarfism. Associated congenital anomalies are rare; however, they need evaluation. We report a 6-month-old Indian girl with SCD who presented with respiratory distress and an asymmetrical small thoracic cavity. The diagnosis was made with radiographs, computed tomography scans, and magnetic resonance imaging (MRI) showing multiple rib and vertebral segmentation anomalies. We would also highlight the importance of MRI in these patients and illustrate other associated brain and spine anomalies.

Neuroimaging features of WOREE syndrome: a mini-review of the literature.

The WWOX gene encodes a 414-amino-acid protein composed of two N-terminal WW domains and a C-terminal short-chain dehydrogenase/reductase (SDR) domain. WWOX protein is highly conserved among species and mainly expressed in the cerebellum, cerebral cortex, brain stem, thyroid, hypophysis, and reproductive organs. It plays a crucial role in the biology of the central nervous system, and it is involved in neuronal development, migration, and proliferation. Biallelic pathogenic variants in WWOX have been associated with an early infantile epileptic encephalopathy known as WOREE syndrome. Both missense and null variants have been described in affected patients, leading to a reduction in protein function and stability. The most severe WOREE phenotypes have been related to biallelic null/null variants, associated with the complete loss of function of the protein. All affected patients showed brain anomalies on magnetic resonance imaging (MRI), suggesting the pivotal role of WWOX protein in brain homeostasis and developmental processes. We provided a literature review, exploring both the clinical and radiological spectrum related to WWOX pathogenic variants, described to date. We focused on neuroradiological findings to better delineate the WOREE phenotype with diagnostic and prognostic implications.

Normative Magnetic Resonance Imaging Data Increase the Sensitivity to Brain Volume Abnormalities in the Classification of Fetal Alcohol Spectrum Disorder

ObjectiveTo evaluate the use of a large MRI normative dataset to quantify structural brain anomalies that may improve diagnostic sensitivity for atypical brain volume in youth with fetal alcohol spectrum disorder (FASD). Study DesignParticipants included 48 children with prenatal alcohol exposure (PAE) and 43 controls, ages 8-17 years, from the longitudinal Collaborative Initiative on Fetal Alcohol Spectrum Disorders. Recently published lifespan brain charts were used to quantify participants’ (per)centile for brain volumes (cortical and subcortical gray matter and cortical white matter), providing an index of (dis)similarity to typically developing individuals of the same age and sex. ResultsParticipants with PAE demonstrated lower mean centile scores compared with controls. Participants with PAE and scores ≤ 10th centile on at least one brain volume metric demonstrated significantly lower performance on measures of intellectual function and aspects of executive functioning compared with participants with PAE and “typical” volumes (>10th centile). Brain volume centiles explained a greater amount of variance in IQ and improved sensitivity to brain volume anomalies in FASD compared with the most commonly used diagnostic criterion of occipitofrontal circumference (OFC) ≤ 10th. ConclusionAge- and sex-adjusted brain volumes based on a large normative dataset may be useful predictors of functional outcomes and may identify a greater number of individuals with FASD than the currently used criterion of OFC.

Surgical treatment of interhemispheric arachnoid cysts.

In children, interhemispheric arachnoid cysts (IHACs) are rare lesions often associated with corpus callosum dysgenesis. It is still controversial about surgical treatments for IHACs. We aim to report our experience with pediatric IHAC patients and evaluate surgical courses and neurological developments. Pediatric IHACs treated between 2001 and 2021 were reviewed retrospectively. IHAC was observed until they represented rapid cyst enlargement or neurological symptoms. Cyst fenestration was done by microscope or endoscope, depending on the IHAC's location. Cyst size and corpus callosum dysgenesis were evaluated with neuroimaging. Neurological development was assessed from medical records at the last follow-up. Fifteen children received cyst fenestration surgery (mean age 11.4months). Eleven patients (73.3%) under observation showed rapid cyst enlargement in a short period (median 5months). Cysto-ventriculostomy (CVS) and cysto-cisternostomy (CCS) regressed the cyst size significantly (p = 0.003). The median follow-up duration was 51months (range 14-178months). Corpus callosum dysgenesis was observed in eleven patients (73.3%, complete = 5, partial = 6). Among eight patients (53.3%) having developmental delay, five patients (33.3%) showed speech delay, including one patient with intractable seizures. Pediatric IHACs frequently present within 1year after birth, with rapid cyst enlargement. CVS and CCS were effective in regressing the cyst size. Corpus callosum dysgenesis accompanied by IHAC might have a risk of language achievement; however, development delay could rely on multifactorial features, such as epilepsy or other brain anomalies.

Asynchronous neural maturation predicts transition to psychosis.

Neuroimaging-based machine-learning predictions of psychosis onset rely on the hypothesis that structural brain anomalies may reflect the underlying pathophysiology. Yet, current predictors remain difficult to interpret in light of brain structure. Here, we combined an advanced interpretable supervised algorithm and a model of neuroanatomical age to identify the level of brain maturation of the regions most predictive of psychosis. We used the voxel-based morphometry of a healthy control dataset (N = 2024) and a prospective longitudinal UHR cohort (N = 82), of which 27 developed psychosis after one year. In UHR, psychosis was predicted at one year using Elastic-Net-Total-Variation (Enet-TV) penalties within a five-fold cross-validation, providing an interpretable map of distinct predictive regions. Using both the whole brain and each predictive region separately, a brain age predictor was then built and validated in 1605 controls, externally tested in 419 controls from an independent cohort, and applied in UHR. Brain age gaps were computed as the difference between chronological and predicted age, providing a proxy of whole-brain and regional brain maturation. Psychosis prediction was performant with 80 ± 4% of area-under-curve and 69 ± 5% of balanced accuracy (P < 0.001), and mainly leveraged volumetric increases in the ventromedial prefrontal cortex and decreases in the left precentral gyrus and the right orbitofrontal cortex. These regions were predicted to have delayed and accelerated maturational patterns, respectively. By combining an interpretable supervised model of conversion to psychosis with a brain age predictor, we showed that inter-regional asynchronous brain maturation underlines the predictive signature of psychosis.

HUT: Hybrid UNet transformer for brain lesion and tumour segmentation

A supervised deep learning network like the UNet has performed well in segmenting brain anomalies such as lesions and tumours. However, such methods were proposed to perform on single-modality or multi-modality images. We use the Hybrid UNet Transformer (HUT) to improve performance in single-modality lesion segmentation and multi-modality brain tumour segmentation. The HUT consists of two pipelines running in parallel, one of which is UNet-based and the other is Transformer-based. The Transformer-based pipeline relies on feature maps in the intermediate layers of the UNet decoder during training. The HUT network takes in the available modalities of 3D brain volumes and embeds the brain volumes into voxel patches. The transformers in the system improve global attention and long-range correlation between the voxel patches. In addition, we introduce a self-supervised training approach in the HUT framework to enhance the overall segmentation performance. We demonstrate that HUT performs better than the state-of-the-art network SPiN in the single-modality segmentation on Anatomical Tracings of Lesions After Stroke (ATLAS) dataset by 4.84% of Dice score and a significant 41% in the Hausdorff Distance score. HUT also performed well on brain scans in the Brain Tumour Segmentation (BraTS20) dataset and demonstrated an improvement over the state-of-the-art network nnUnet by 0.96% in the Dice score and 4.1% in the Hausdorff Distance score.

Diagnostic yield of prenatal exome sequencing in the genetic screening of fetuses with brain anomalies detected by MRI and ultrasonography: A systematic review and meta-analysis.

Brain anomalies (BAs) have been the focus of research, as they have a high impact on fetal health but therapeutic and diagnostic approaches are limited. In this study, the application and efficiency of exome sequencing (ES) in detecting different cases of BAs in fetuses were evaluated and compared with chromosomal microarray analysis (CMA). To conduct this study, three databases including PubMed, Web of Science and Embase were utilised with the keywords 'prenatal', 'diagnoses', 'brain anomalies' and 'exome sequencing'. Studies were included based on the STARD checklist, for which the ES and CMA diagnostic yields were calculated. Meta-analysis was performed on the included studies using a random-effects model and subgroup analysis to define the risk difference between them. We included 11 studies representing 779 fetuses that implemented ES along with imaging techniques. The pooled ES diagnostic yield in fetuses with BAs detected through magnetic resonance imaging (MRI) and ultrasonography was 26.53%, compared with 3.46% for CMA. The risk difference between ES and CMA for complex BAs was 0.36 [95% confidence interval (CI) 0.24-0.47], which was higher than for single BAs (0.22; 95% CI 0.18-0.25]. ES is a useful method with a significantly higher diagnostic yield than CMA for genetic assessment of fetuses with complex BAs detected by imaging techniques. Moreover, ES could be applied to suspected fetuses with related family histories to predict congenital diseases with high efficiency.