Brain Magnetic Resonance Imaging Studies Research Articles

Human Brain Magnetic Resonance Imaging Studies for Psychiatric Disorders: The Current Progress and Future Directions.

With the prevalence of psychiatric disorders and the limitations of the diagnostic scheme and treatment options of these disorders, magnetic resonance imaging (MRI) studies play a significant role in uncovering the pathological basis of psychiatric disorders and potentially using biological markers in clinical settings. The use of MRI in clinical research has grown over the past three decades, and current MRI research continues to provide an avenue to guide the development of diagnostic approaches and therapeutic solutions. However, the current shortcomings of MRI studies derive not only from technical limitations (i.e., the range of contrasts that MRI probes or sensors can create) but also from confounding factors in the current methodological approaches of case-control studies for psychiatric disorders. Thus, by reviewing the recent literature on MRI research on psychiatric disorders, we explain the current progress and limitations of brain MRI methodologies used to study psychiatric disorders. We consider the growing use of cross-disorder methods to identify shared and disease-specific pathological features across psychiatric disorders. In addition, we need to outline healthy developmental and aging changes of the brain and investigate the disorder difference as a deviation of the trajectory. Although these methods have provided us with new insights, the demarcation between psychiatric disorders based on a definitive set of pathologies remains limited. This challenge of disease stratification is further complicated by the presence of multiple different sets of disorder pathologies within a single disorder and the different progressive timelines of different disorders. As such, we introduce the ongoing research projects in Japan, namely, the Brain Mapping by Integrated Neurotechnologies for Disease Studies (Brain/MINDS) and the Strategic International Brain Science Research Promotion Program (Brain/MINDS Beyond). These collaborative research initiatives across Japan use neuroimaging and travel-subject harmonization to conduct nationwide MRI studies capable of providing large-scale coherent results, which may address the current limitations of MRI psychiatric disorder research.

A vertebral artery aneurysm that elicited occipital pain, showed no abnormalities on imaging studies, but ruptured the next day: illustrative case.

The authors report the case of a patient with occipital headache whose imaging studies revealed no abnormalities but who died 1 day later due to vertebral artery (VA) aneurysm rupture. A male in his 40s with no relevant medical history had been taking over-the-counter medication for headache several times a month. One day before he visited our neurosurgery department, he experienced occipital headache, took the usual medicine, and applied a warm compress. Brain magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) studies returned no abnormal findings, and he went home. On the following day, his wife found his lifeless body in rigor mortis and requested a medicolegal autopsy. Preautopsy brain computed tomography showed diffuse subarachnoid hemorrhage (SAH). Histopathologically, there was no obvious VA dissection. The vascular wall at the rupture site lacked internal elastic lamina and media, it was covered only with thin fibrous connective tissue, and the adventitia was expanded. The cause of death was determined to be SAH due to rupture of a VA blister aneurysm. In our patient, brain MRI and MRA studies returned no abnormal findings. However, he died suddenly the next day. Autopsy identified SAH due to rupture of a blister-like VA aneurysm without dissection.

THU205 A Case Of Infant With Familial-Male Limited Precocious Puberty (FMPP) Inherited From Father Due To An Activating Mutation Of The Luteinizing Hormone/Chorionic Gonadotropin Receptor Gene

Abstract Disclosure: H. Yoo: None. J. Ha: None. M. Jung: None. Y. Choi: None. E. Yoo: None. We present an extremely rare case of FMPP with an activating mutation of the LHCGR gene in a Korean infant. A 16-month-old-boy was brought to the out-patient clinic with complaints of pubic hair, acne and rapid growth acceleration. His father had become aware of the symptoms 4 month before. His grandfather and father had a family history of precocious puberty and profound short stature (Height of grandfather and father: 148 cm and 158 cm respectively). At physical examination, his height was 83 cm (+1.2 SDS) and his weight was 14.3 kg (+2.8 SDS). The testicular volume was 2 mL and pubic hair was appropriate for Tanner stage 2. Stretched penile length was 7 cm (>2 SDS). He did not have any café au lait spots or hyperpigmentation. His bone age was significantly advanced to that of a 4 year old. Laboratory findings showed abnormally elevated serum testosterone (5.74 ng/mL) and slightly elevated α-fetoprotein (14.1 ng/ml; reference 0-10 ng/mL) with suppressed LH level (<0.07 mIU/mL). Serum levels of β-human chorionic gonadotropin, cortisol, 17-hydroxyprogesterone, androstenedione and dehydroepiandrosterone sulfate were within normal range. A gonadotropin releasing hormone (GnRH) stimulation test revealed a prepubertal response(peak LH 0.52). Brain magnetic resonance imaging study was reported to be normal. Ultrasound of the scrotum and adrenal gland were both normal. Due to the patient’s classic presentation and his family history of male-limited precocious puberty, a genetic analysis for LHCGR gene was performed. Molecular genetic analysis identified a pathogenic variant of LHCGR (c.1730 C>T, p.Thr577Ileu), which was previously reported in a FMPP patient. His father and paternal grand father also carry the same mutation. Anti-androgen treatment with bicalutamide (25mg/day) and aromatase inhibition with anastrozole (1mg/day) were initiated. After treatment, there was improvement in pubertal progression, accelerated growth velocity and rate of skeletal maturation without any specific side effects. Presentation: Thursday, June 15, 2023

A retrospective study of structural brain lesions identified by magnetic resonance imaging in 114 cats with neurological signs.

Magnetic resonance imaging (MRI) has been widely used as a non-invasive modality to evaluate neurological organ structures. However, brain MRI studies in cats with neurological signs are limited. This study evaluated the association between patient characteristics, neurological signs, and brain lesion locations identified by MRI. Blood profiles of cats with presumptive inflammatory and structural brain lesions were also determined. Medical records of 114 cats that underwent brain MRI were retrospectively reviewed. Cats were categorized into five groups based on the location of their lesion: Cerebrum, brainstem, cerebellum, multifocal, and non-structural. Patient characteristics, neurological signs, and hematological profiles were obtained from their medical records. Disease classification was categorized based on their etiologies. Associations were determined using Fisher's exact test. Blood parameters were compared using the Kruskal-Wallis test. A total of 114 cats met the inclusion criteria. Lesions were identified in the cerebrum (21.1%), brainstem (8.8%), cerebellum (6.1%), multifocal (39.5%), and non-structural (24.6%) of the cats. Common neurological signs included seizure activity (56.1%), cerebellar signs (41.2%), and anisocoria (25.4%). The most common brain abnormality was inflammation (40.4%). There was no significant difference in hematological profiles between cats with presumptive inflammatory and non-inflammatory brain lesions. Neutrophils, platelets, total protein, and globulin concentrations were higher in cats with structural brain lesions. The most common neurological signs and brain disease category were seizure activity and inflammation, respectively. However, the hematological profile did not predict inflammatory and structural brain lesions.

Magnetic Resonance Imaging-Based Distribution and Reversibility of Lesions in Pediatric Vigabatrin-Related Brain Toxicity

BackgroundWe aimed to systematically characterize the magnetic resonance imaging (MRI) findings in vigabatrin-related neurotoxicity in children and determine the reversibility of lesions based on follow-up images. MethodsWe evaluated children with a history of refractory seizures who had a brain MRI while on vigabatrin therapy. We included available brain MRI studies before vigabatrin therapy initiation, during vigabatrin treatment, and after vigabatrin was discontinued. A pediatric neuroradiologist systematically assessed images on T2/fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging /apparent diffusion coefficient sequences to identify hyperintense lesions and/or restricted diffusion. The frequency of abnormal signal at each location was determined, as well as the reversibility of these after vigabatrin discontinuation. ResultsMRIs of 43 patients were reviewed: 13 before vigabatrin initiation, 18 during treatment, and 12 after vigabatrin discontinuation. In the MRIs acquired during vigabatrin treatment, most lesions on T2/FLAIR occurred in the globus pallidi, thalami, and midbrain. Correspondingly, the most common locations for restricted diffusion were the globus pallidi, thalami, and subthalamic nuclei. On MRI after vigabatrin discontinuation, complete resolution of lesions on T2/FLAIR in all patients was seen in the midbrain, dentate nuclei, subthalamic nuclei, and hypothalami. Complete resolution of restricted diffusion was observed in the globus pallidi, midbrain, dentate nuclei, hippocampi, anterior commissure, and hypothalami. ConclusionGlobus pallidi and thalami are the most commonly affected structures in vigabatrin-related toxicity, and most vigabatrin-related neuroimaging findings are reversible.

Pathogenesis, clinical features and treatment of anti‐IgLON5 disease

AbstractAnti‐immunoglobulin‐like cell adhesion molecule 5 (IgLON5) disease is an autoimmune encephalitis that targets the cell adhesion molecule, IgLON5. The disease presents with various clinical features, including sleep disorders, bulbar palsy, movement disorders, cognitive dysfunction and neuromuscular manifestations. Sleep disorders are characterized by parasomnias and sleep‐disordered breathing (stridor and sleep apnea). Bulbar palsy includes dysarthria, dysphagia, vocal cord paralysis and stridor. Movement disorders include a variety of symptoms and signs, such as chorea, dystonia, rigidity, tremor, myoclonus and myorhythmia. Cognitive dysfunction includes executive dysfunction, impairment of attention, and verbal and visual memory dysfunction. Neuromuscular manifestations include fasciculations in the tongue and peripheral muscles, limb weakness, and muscle atrophy. Some patients resemble those with neurodegenerative diseases, such as progressive supranuclear palsy or amyotrophic lateral sclerosis. On video polysomnography, undifferentiated non‐rapid eye movement sleep and poorly structured N2 sleep are characteristic. Brain magnetic resonance imaging and cerebrospinal fluid studies are often normal or non‐specific. Human leukocyte antigen testing shows that HLA‐DRB1*10:01‐DQB1*05:01 is highly associated with the disease. Pathologically, neuronal deposition of both hyperphosphorylated 3‐repeat and 4‐repeat tau isoforms, neuronal loss, and gliosis in the hypothalamus, brainstem tegmentum, and upper cervical cord are observed. Some patients are responsive to immunotherapies, such as steroids, intravenous immunoglobulin, plasma exchange therapy and rituximab. Factors associated with a favorable response to immunotherapies include early initiation of treatment, cerebrospinal fluid inflammation and immunoglobulin G1 (IgG1) predominance of IgLON5 antibody compared with immunoglobulin G4 (IgG4). Anti‐IgLON5 disease should be suspected in patients with atypical movement disorders complicated by sleep disturbances.

Neurocognitive Profile and 18 F-Fluorodeoxyglucose Positron Emission Tomography Brain Imaging Correlation in Children with Electrical Status Epilepticus during Sleep.

Objective  Electrical status epilepticus in sleep (ESES) is defined by near-continuous epileptiform discharges during sleep along with cognitive, behavioral, and/or imaging abnormalities. We studied the neurocognitive profile and their correlation with 18 F fluorodeoxyglucose positron emission tomography (FDG PET) brain abnormalities in children with ESES. Methods  Fourteen children with ESES with normal magnetic resonance imaging (MRI) from March to December 2019 were included. The intelligence quotient (IQ) and child behavior checklist (CBCL) scores were estimated using validated scales, and FDG PET brain was done at the same point of time to look for cerebral metabolic defects which was compared with a control group. Results  Fourteen patients with a mean age of 8.2 ± 2.7 years were analyzed. The average duration of epilepsy was 6 ± 2.8 years. The mean IQ was 72.4 ± 18.2 and mean CBCL score was 37.3 ± 11.8. There was negative correlation between IQ and CBCL ( r  = -0.55, p  < 0.001). The duration of epilepsy also showed negative correlation with IQ ( r  = -4.75, p  < 0.001). FDG PET scan showed predominant thalamic hypometabolism in 12 of 14 patients (85.7%) on visual analysis with multiple other hypometabolic cortical and subcortical regions in the brain. The quantitative analysis showed significant difference in metabolism of basal ganglion when compared with control group. The total number of hypometabolic regions seen in the brain showed moderate positive correlation with CBCL score but no significant correlation with the IQ of cases. Conclusion  This study demonstrates functional impairment of cerebral cortical, basal ganglia, and thalamic hypometabolism in a cohort of ESES patients with normal structural MRI brain study. There was a moderate correlation of extent and pattern of cerebral hypometabolism with the neuropsychological status of the child and duration of epilepsy.

Advancing (Neuro)Entrepreneurship Cognition Research Through Resting-State fMRI: A Methodological Brief

Despite many calls, functional brain magnetic resonance imaging (fMRI) studies are relatively rare in the domain of entrepreneurship research. This methodological brief presents the brain-imaging method of resting-state fMRI (rs-fMRI) and illustrates its application in neuroentrepreneurship for the first time. In contrast to the traditional task-based fMRI approach, rs-fMRI observes the brain in the absence of cognitive tasks or presentation of stimuli, which offers benefits for improving our understanding of the entrepreneurial mind. Here, we describe the method and provide methodological motivations for performing brain resting-state functional neuroimaging studies on entrepreneurs. In addition, we illustrate the use of seed-based correlation analysis, one of the most common analytical approaches for analyzing rs-fMRI data. In this illustration, we show that habitual entrepreneurs have increased functional connectivity between the insula (a region associated with cognitive flexibility) and the anterior prefrontal cortex (a key region for explorative choice) as compared to managers. This increased connectivity could help promote flexible behavior. Thus in brief, we provide an exemplar of a novel way to expand our understanding of the brain in the domain of entrepreneurship. We discuss possible directions for future research and challenges to be addressed to facilitate the inclusion of re-fMRI studies into neuroentrepreneurship.

Pediatric optic nerve and globe measurements on magnetic resonance imaging: establishing norms for children.

Normal optic nerve diameter (OND) and optic nerve sheath diameter (ONSD) may be beneficial for describing optic nerve pathway abnormality reflecting increased intracranial pressure. Nonetheless, magnetic resonance imaging (MRI) measurement of the normal ONSD range and its associations with clinical factors and eyeball transverse diameter (ETD) are not well established in children. To establish normal OND, ONSD, ETD, and OND/ONSD and ONSD/ETD measurements in children and their associations with age and sex. We evaluated and analyzed 336 brain MRI studies of children aged 0.5 months to 18 years. We measured a total of 672 optic nerves. The OND and ONSD were measured 1 cm anterior to the optic foramina and 3 mm behind the optic disc on an axial T2 sequence. The mean OND 3 mm and 1 cm, ONSD 3 mm and 1 cm, and ETD were 0.23 ± 0.05 mm and 0.16 ± 0.04 mm, 0.53 ± 0.08 mm and 0.38 ± 0.06 mm, and 2.3 ± 0.13, respectively. Only ONSD 1 cm was independent of age (P = 0.247). ONSD 3 mm and ETD were significantly wider in boys compared to girls and significantly influenced by age (both P < 0.001). Age at scan and ETD were significantly correlated (P < 0.001). We established MRI-based OND, ONSD, ETD, and ONSD/ETD and OND/ONSD ratio normative values in children, which can be helpful in pediatric populations with disease.

Tohoku Medical Megabank Brain Magnetic Resonance Imaging Study: Rationale, Design, and Background.

The Tohoku Medical Megabank Brain Magnetic Resonance Imaging Study (TMM Brain MRI Study) was established to collect multimodal information through neuroimaging and neuropsychological assessments to evaluate the cognitive function and mental health of residents who experienced the Great East Japan Earthquake (GEJE) and associated tsunami. The study also aimed to promote advances in personalized healthcare and medicine related to mental health and cognitive function among the general population. We recruited participants for the first (baseline) survey starting in July 2014, enrolling individuals who were participating in either the TMM Community-Based Cohort Study (TMM CommCohort Study) or the TMM Birth and Three-Generation Cohort Study (TMM BirThree Cohort Study). We collected multiple magnetic resonance imaging (MRI) sequences, including 3D T1-weighted sequences, magnetic resonance angiography (MRA), diffusion tensor imaging (DTI), pseudo-continuous arterial spin labeling (pCASL), and three-dimensional fluid-attenuated inversion recovery (FLAIR) sequences. To assess neuropsychological status, we used both questionnaire- and interview-based rating scales. The former assessments included the Tri-axial Coping Scale, Impact of Event Scale in Japanese, Profile of Mood States, and 15-item Depression, Anxiety, and Stress Scale, whereas the latter assessments included the Mini-Mental State Examination, Japanese version. A total of 12,164 individuals were recruited for the first (baseline) survey, including those unable to complete all assessments. In parallel, we returned the MRI results to the participants and subsequently shared the MRI data through the TMM Biobank. At present, the second (first follow-up) survey of the study started in October 2019 is underway. In this study, we established a large and comprehensive database that included robust neuroimaging data as well as psychological and cognitive assessment data. In combination with genomic and omics data already contained in the TMM Biobank database, these data could provide new insights into the relationships of pathological processes with neuropsychological disorders, including age-related cognitive impairment.

Selective vulnerability of brainstem and cervical spinal cord regions in people with non-progressive multiple sclerosis of Black or African American and European ancestry

Background: We evaluated imaging features suggestive of neurodegeneration within the brainstem and upper cervical spinal cord (UCSC) in non-progressive multiple sclerosis (MS). Methods: Standardized 3-Tesla three-dimensional brain magnetic resonance imaging (MRI) studies were prospectively acquired. Rates of change in volume, surface texture, curvature were quantified at the pons and medulla-UCSC. Whole and regional brain volumes and T2-weighted lesion volumes were also quantified. Independent regression models were constructed to evaluate differences between those of Black or African ancestry (B/AA) and European ancestry (EA) with non-progressive MS. Results: 209 people with MS (pwMS) having at least two MRI studies, 29% possessing 3–6 timepoints, resulted in 487 scans for analysis. Median follow-up time between MRI timepoints was 1.33 (25th–75th percentile: 0.51–1.98) years. Of 183 non-progressive pwMS, 88 and 95 self-reported being B/AA and EA, respectively. Non-progressive pwMS demonstrated greater rates of decline in pontine volume (p < 0.0001) in B/AA and in medulla-UCSC volume (p < 0.0001) for EA pwMS. Longitudinal surface texture and curvature changes suggesting reduced tissue integrity were observed at the ventral medulla-UCSC (p < 0.001), dorsal pons (p < 0.0001) and dorsal medulla (p < 0.0001) but not the ventral pons (p = 0.92) between groups. Conclusions: Selectively vulnerable regions within the brainstem-UCSC may allow for more personalized approaches to disease surveillance and management.

Reply: Cerebral Blood Flow of the Frontal Lobe in Untreated Children with Trigonocephaly versus Healthy Controls: An Arterial Spin Labeling Study.

We have read with great interest the letter from Long et al. regarding our article.1 Their letter stated two methodological concerns to which we will respond. The first concern is that objective criteria are missing for true trigonocephaly or benign metopic ridge. We only included patients with moderate to severe trigonocephaly according to the definitions of Birgfeld et al.2 In their article, Birgfeld et al. provide a phenotypical distinction between benign metopic ridge and metopic synostosis, as well as illustrative photographs with corresponding computed tomographic imaging.2 Cho et al.3 and Anolik et al.4 described computed tomographic measures to assess severity of metopic synostosis. In both studies, the cut-off point to determine surgical indication remained subjective, and poor consensus for the intermediate presentation of metopic craniosynostosis was found. In addition, Sisti et al.5 recently reviewed all literature in PubMed on trigonocephaly, relating to 15 anthropometric cranial measurements for surgical indications. They found that most articles have a lack of diagnostic criteria for trigonocephaly. At our center, the decision for surgery is made through shared decision-making with parents. In 2021, this resulted in surgery for 14 patients (moderate or severe presentation) and a conservative treatment for 40 patients (18 with mild presentation and 22 with moderate or severe presentation). The second concern Long et al. raise is the potential blunting effect of sevoflurane on cerebral blood flow (CBF). If there is a blunting effect, a similar effect on both patients and controls is expected. In our previous arterial spin labeling study in patients with syndromic craniosynostosis using the same sedation protocol, we found a difference between the groups.6 This suggests that the normal findings in patients with trigonocephaly reflect normal CBF. Very few studies have investigated the influence of anesthesia on arterial spin labeling CBF in the pediatric population. Carsin-Vu et al.7 included 84 subjects ranging in age from 6 months to 15 years and showed no significant CBF changes with sevoflurane in comparison to general anesthesia. Kaisti et al.8 showed in eight healthy male patients (age range, 20 to 26 years) that sevoflurane reduced regional CBF less than propofol did. Without sedation, scanning of one sequence is possible, because of the limited timeframe. However, more sequences, as in our protocol, requires a longer time period. Without sedation, motion artifacts would make it impossible to analyze. Finally, Long et al. mention that cerebral perfusion is a limited measure of neurodevelopment and that functional magnetic resonance imaging (MRI) studies in patients with scaphocephaly have shown a difference in functional brain connectivity compared with controls. However, there is still a lot unknown about the optimal method of scanning, reproducibility, and interpretation of functional MRI results. Finding a difference in connectivity in functional MRI studies would be at the same level of evidence as the arterial spin labeling brain MRI study.9 To conclude, our study further supports our hypothesis that surgery for trigonocephaly is rarely indicated functionally. Parents should be informed about the unknown added value of surgery regarding raised intracranial pressure and brain perfusion. Comparative research on outcome of conservative versus surgical treatment of moderate to severe trigonocephaly is needed to establish clinical guidelines. DISCLOSURE The authors have no financial interest to declare in relation to the content of this communication. Catherine A. de Planque, MDDepartment of Plastic, Reconstructive Surgery, and Hand SurgeryErasmus MC-Sophia Children’s HospitalUniversity Medical Center RotterdamRotterdam, The Netherlands Jan Petr, PhDHelmholtz-Zentrum Dresden-RossendorfInstitute of Radiopharmaceutical Cancer ResearchDresden, Germany Linda Gaillard, MDDepartment of Plastic, Reconstructive Surgery, and Hand SurgeryErasmus MC-Sophia Children’s HospitalUniversity Medical Center RotterdamRotterdam, The Netherlands Henk J. M. M. Mutsaerts, MD, PhDVrije Universiteit AmsterdamAmsterdam NeuroscienceAmsterdam, The Netherlands Marie-Lise C. van Veelen, MD, PhDDepartment of Neurosurgery Sarah L. Versnel, MD, PhDDepartment of Plastic, Reconstructive Surgery, and Hand Surgery Marjolein H. G. Dremmen, MDDepartment of Radiology and Nuclear Medicine Irene M. J. Mathijssen, MD, PhD, MBA-HDepartment of Plastic, Reconstructive Surgery, and Hand SurgeryErasmus MC-Sophia Children’s HospitalUniversity Medical Center RotterdamRotterdam, The Netherlands

Brain magnetic resonance imaging findings among children with epilepsy in two urban hospital settings, Kampala-Uganda: a descriptive study

BackgroundEpilepsy is one of the most common neurological conditions in children worldwide. Its presentation is heterogeneous, with diverse underlying aetiology, clinical presentation, and prognosis. Structural brain abnormalities are among the recognized causes of epilepsy. Brain Magnetic Resonance Imaging (MRI) is the imaging modality of choice for epilepsy workup.We aimed to determine the prevalence and describe the structural abnormalities identified in the brain MRI studies performed on children with epilepsy from two urban hospitals in Kampala, Uganda.MethodsThis was a cross-sectional descriptive study performed at two urban hospital MRI centres. The study population was 147 children aged 1 day to 17 years with confirmed epilepsy. Brain MRI was performed for each child and a questionnaire was used to collect clinical data.ResultsThe prevalence of structural abnormalities among children with epilepsy was 74.15% (109 out of 147). Of these, 68.81% were male, and the rest were female. Among these, the majority, 40.14% (59 of 144) were aged 1 month to 4 years. Acquired structural brain abnormalities were the commonest at 69.22% with hippocampal sclerosis (HS) leading while disorders of cortical development were the most common congenital causes.An abnormal electroencephalogram (EEG) was significant for brain MRI abnormalities among children with epilepsy with 95% of participants with an abnormal EEG study having epileptogenic structural abnormalities detected in their brain MRI studies.Conclusion and recommendationTwo-thirds of children with epilepsy had structural brain abnormalities. Abnormal activity in the EEG study was found to positively correlate with abnormal brain MRI findings. As such, EEG study should be considered where possible before MRI studies as a determinant for children with epilepsy who will be having imaging studies done in the Ugandan setting.

Influence of temporal muscle thickness on the outcome of radiosurgically treated patients with brain metastases from non-small cell lung cancer.

The purpose of this study was to assess the impact of temporal muscle thickness (TMT), a surrogate marker for sarcopenia, in radiosurgically treated patients with brain metastases (BMs) from non-small cell lung cancer (NSCLC). For 566 patients with BMs from NSCLC in the period between June 2012 and December 2019, TMT values were retrospectively measured on the planning brain magnetic resonance imaging (MRI) studies that had been obtained before their first Gamma Knife radiosurgery treatment (GKRS1). Predefined sex-specific TMT cutoff values were used to stratify the study cohort into patients at risk for sarcopenia and patients with normal muscle status. Cox regression models adjusted for other prognostic parameters were used to evaluate sarcopenia as an independent prognostic factor. In sarcopenia patients with a TMT below the sex-specific cutoff values, the risk of death was significantly increased (HR 1.908, 95% CI 1.550-2.349, p < 0.001). In addition, sarcopenia was revealed as an independent prognostic factor even after adjusting for age groups, sex, number of BMs, presence of extracranial metastases, NSCLC subtypes, Karnofsky Performance Status groups, recursive partitioning analysis classes, and concomitant immunotherapy or targeted therapy (HR 1.680, 95% CI 1.347-2.095, p < 0.001). However, patients at risk for sarcopenia showed no significant differences in the estimated mean time until local BM progression after GKRS1, compared to patients with normal muscle status (p = 0.639). TMT obtained from planning MRI studies is an independent prognostic marker in radiosurgically treated patients with BMs from NSCLC and may aid patient stratification in future clinical trials.

Brain Magnetic Resonance Imaging Findings in Patients with Developmental Delay in Addis Ababa, Ethiopia.

Developmental delay is a major health problem throughout the world causing significant individual disability. Even though physical examination and patient history are the most important and basic evaluations of patients with developmental delay, additional investigations are usually required in supporting or reaching a diagnosis among which is neuroimaging. This study aims to assess brain Magnetic resonance imaging (MRI) patterns in patients presented with developmental delay. A retrospective analysis of 164 patients who had undergone brain Magnetic Resonance Imaging (MRI) evaluation for the developmental delay was done. The study was conducted between March to November 2021 G.C at Tikur Anbessa Specialized Hospital (TASH). The patients' clinical history and magnetic resonance imaging reports were reviewed from their medical records. All patients with developmental delay who had brain MRI evaluation at TASH and at one private diagnostic center in Addis Ababa were included in the study. A total of 164 patients were included in this study of which 95(57.9%) were male and 69(42.1%) female patients were seen. A total of 120 patients (73.2%) showed abnormal brain MRI studies. Previous neurovascular insults were the most common abnormalities seen in 75(45.7%) patients followed by imaging findings of congenital and developmental abnormalities seen in 20(12.2%) patients. Brain MRI is an important input in the evaluation of patients with developmental delay. It can give evidence for the cause of developmental delay, especially in the diagnosis of perinatal/hypoxic-ischemic insults, and congenital and developmental malformations.

Congenital Adrenal Hyperplasia and Brain Health: A Systematic Review of Structural, Functional, and Diffusion Magnetic Resonance Imaging (MRI) Investigations.

Congenital adrenal hyperplasia (CAH) is a group of genetic disorders that affects the adrenal glands and is the most common cause of primary adrenal insufficiency in children. In the past few decades, magnetic resonance imaging (MRI) has been implemented to investigate how the brain may be affected by CAH. A systematic review was conducted to evaluate and synthesize the reported evidence of brain findings related to CAH using structural, functional, and diffusion-weighted MRI. We searched bibliographical databases through July 2021 for brain MRI studies in individuals with CAH. Twenty-eight studies were identified, including 13 case reports or series, 10 studies that recruited and studied CAH patients vs unaffected controls, and 5 studies without a matched control group. Eleven studies used structural MRI to identify structural abnormalities or quantify brain volumes, whereas 3 studies implemented functional MRI to investigate brain activity, and 3 reported diffusion MRI findings to assess white matter microstructure. Some commonly reported findings across studies included cortical atrophy and differences in gray matter volumes, as well as white matter hyperintensities, altered white matter microstructure, and distinct patterns of emotion and reward-related brain activity. These findings suggest differences in brain structure and function in patients with CAH. Limitations of these studies highlight the need for CAH neuroimaging studies to incorporate larger sample sizes and follow best study design and MRI analytic practices, as well as clarify potential neurologic effects seen across the lifespan and in relation to clinical and behavioral CAH phenotypes.

ID-Seg: an infant deep learning-based segmentation framework to improve limbic structure estimates

Infant brain magnetic resonance imaging (MRI) is a promising approach for studying early neurodevelopment. However, segmenting small regions such as limbic structures is challenging due to their low inter-regional contrast and high curvature. MRI studies of the adult brain have successfully applied deep learning techniques to segment limbic structures, and similar deep learning models are being leveraged for infant studies. However, these deep learning-based infant MRI segmentation models have generally been derived from small datasets, and may suffer from generalization problems. Moreover, the accuracy of segmentations derived from these deep learning models relative to more standard Expectation–Maximization approaches has not been characterized. To address these challenges, we leveraged a large, public infant MRI dataset (n = 473) and the transfer-learning technique to first pre-train a deep convolutional neural network model on two limbic structures: amygdala and hippocampus. Then we used a leave-one-out cross-validation strategy to fine-tune the pre-trained model and evaluated it separately on two independent datasets with manual labels. We term this new approach the Infant Deep learning SEGmentation Framework (ID-Seg). ID-Seg performed well on both datasets with a mean dice similarity score (DSC) of 0.87, a mean intra-class correlation (ICC) of 0.93, and a mean average surface distance (ASD) of 0.31 mm. Compared to the Developmental Human Connectome pipeline (dHCP) pipeline, ID-Seg significantly improved segmentation accuracy. In a third infant MRI dataset (n = 50), we used ID-Seg and dHCP separately to estimate amygdala and hippocampus volumes and shapes. The estimates derived from ID-seg, relative to those from the dHCP, showed stronger associations with behavioral problems assessed in these infants at age 2. In sum, ID-Seg consistently performed well on two different datasets with an 0.87 DSC, however, multi-site testing and extension for brain regions beyond the amygdala and hippocampus are still needed.

Cognitive profile in idiopathic autonomic failure: relation with white matter hyperintensities and neurofilament levels.

ObjectiveTo disclose the nature of cognitive deficits in a cohort of patients with idiopathic autonomic failure (IAF) by exploring the relation among cognitive functions, cardiovascular autonomic failure (AF) and clinical progression to another α‐synucleinopathy (phenoconversion).MethodsWe retrospectively identified all patients with a clinical diagnosis of IAF who underwent a comprehensive neuropsychological evaluation, clinical examination and cardiovascular autonomic tests from the IAF‐BO cohort. Brain magnetic resonance imaging (MRI) studies and cerebrospinal fluid (CSF) analysis, including neurofilament light chain (NfL), Alzheimer disease core biomarkers, and α‐synuclein seeding activity were further evaluated when available.Correlations among cognitive functions, clinical features, cardiovascular AF, cerebral white matter hyperintensities (WMH) load, and CSF biomarkers were estimated using Spearman correlation coefficient.ResultsThirteen out of 30 (43%) patients with IAF displayed cognitive deficits (CI) mainly concerning executive functioning. Seven out of 30 (23%) met the criteria for mild cognitive impairment (MCI).The diagnosis of CI and MCI was not associated with phenoconversion or autonomic function parameters, including duration and severity of neurogenic orthostatic hypotension, presence and severity of supine hypertension, and nocturnal dipper profile.Twenty patients underwent a brain MRI and CSF analysis. MCI was related to WMH load (r = 0.549) and NfL levels (r = 0.656), while autonomic function parameters were not associated with either WMH or NfL levels.InterpretationCardiovascular AF and phenoconversion, underlying the spreading of neurodegeneration to the central nervous system, were not independent drivers of cognitive dysfunction in IAF. We identified WMH load and NfL levels as potential biomarkers of the neural network disruption associated with cognitive impairment in patients with IAF.

Does Long-Duration Exposure to Microgravity Lead to Dysregulation of the Brain and Ocular Glymphatic Systems?

Spaceflight-associated neuro-ocular syndrome (SANS) has been well documented in astronauts both during and after long-duration spaceflight and is characterized by the development of optic disc edema, globe flattening, choroidal folds, and hyperopic refractive error shifts. The exact mechanisms underlying these ophthalmic abnormalities remain unclear. New findings regarding spaceflight-associated alterations in cerebrospinal fluid spaces, specifically perivascular spaces, may shed more light on the pathophysiology of SANS. The preliminary results of a recent brain magnetic resonance imaging study show that perivascular spaces enlarge under prolonged microgravity conditions, and that the amount of fluid in perivascular spaces is linked to SANS. The exact pathophysiological mechanisms underlying enlargement of perivascular spaces in space crews are currently unclear. Here, we speculate that the dilation of perivascular spaces observed in long-duration space travelers may result from impaired cerebral venous outflow and compromised cerebrospinal fluid resorption, leading to obstruction of glymphatic perivenous outflow and increased periarterial cerebrospinal fluid inflow, respectively. Further, we provide a possible explanation for how dilated perivascular spaces can be associated with SANS. Given that enlarged perivascular spaces in space crews may be a marker of altered venous hemodynamics and reduced cerebrospinal fluid outflow, at the level of the optic nerve and eye, these disturbances may contribute to SANS. If confirmed by further studies, brain glymphatic dysfunction in space crews could potentially be considered a risk factor for the development of neurodegenerative diseases, such as Alzheimer’s disease. Furthermore, long-duration exposure to microgravity might contribute to SANS through dysregulation of the ocular glymphatic system. If prolonged spaceflight exposure causes disruption of the glymphatic systems, this might affect the ability to conduct future exploration missions, for example, to Mars. The considerations outlined in the present paper further stress the crucial need to develop effective long-term countermeasures to mitigate SANS-related physiologic changes during long-duration spaceflight.

Direction and magnitude of displacement differ between slowly expanding and non-expanding multiple sclerosis lesions as compared to small vessel disease.

Differentiating between multiple sclerosis (MS) and small vessel disease (SVD) lesions represents a key challenge in the day-to-day management of patients. We aimed to distinguish between MS and SVD by identifying the dynamics of lesion movement patterns between enlarging and contracting foci from two MRI time points. Standardized 3-Tesla 3-dimensional brain magnetic resonance imaging (MRI) studies were performed at two time points on enrolled MS and SVD patients. Selected supratentorial lesions were segmented and longitudinal changes in the direction of lesion displacement and magnitude along with the evolution of contracting and expanding T1-weighted and T2-weighted MS lesions were quantified based on lesion centroid positioning. Bayesian linear mixed effects regression models were constructed to evaluate associations between changes in lesion transitions and disease state. A total of 420 lesions were analyzed from 35 MS (female (F):22 (62.9%); median age (range):38years (y) (22-61), median disease duration:7.38y (0.38-20.99)) and 12 SVD patients (F:11 (100%); 54y (40-66)). MS T2-weighted lesions that increased in volume between MRI time points demonstrated movement toward the cortex (p = 0.01), whereas those that decreased in volume moved toward the center (p < 0.0001). Lesion volume changes related to SVD demonstrated no effect on movement direction over time. Both expanding (p = 0.03) and contracting (p = 0.01) MS lesions demonstrated greater distances between centroids when compared to SVD. Lesion dynamics may reveal distinct characteristics associated with the biology of disease while providing further insights into the behavior of inflammatory CNS disorders.