Neuroimaging in spasticity and movement disorders

MRCT and CT in the diagnosis of pediatric disease imaging: assessing imaging performance and clinical effects

OBJECTIVE

This study focused on analyzing the clinical value and effect of magnetic resonance imaging plus computed tomography (MRCT) and CT in the clinical diagnosis of cerebral palsy in children.

METHODS

From February 2021 to April 2023, 94 children diagnosed with cerebral palsy were selected from our hospital for study subjects. These patients were divided into CT and MRI groups, with CT examination given to the CT group and MRI examination given to the MRI group. The positive rate of the two examination methods in the diagnosis of cerebral palsy was compared, different imaging signs in two groups of children with cerebral palsy were compared, and the diagnostic test typing results between two groups were further analyzed.

RESULTS

The diagnostic positivity rate of the children in the MRI group was 91.49%, which was significantly higher than that of the children in the CT group (70.21%) (P < 0.05). In both groups, encephalomalacia, bilateral frontal subdural effusions, and gray-white matter atrophy of the brain were the main signs, and the difference in the proportion of these three imaging signs between the two groups was not significant (P > 0.05). Differences between the two groups examined for cerebral palsy subtypes were not significant (P > 0.05).

CONCLUSION

The positive rate of pediatric cerebral palsy examined by MRI is higher than that of CT diagnosis, but the clinic should organically combine the two to further improve the detection validity and accuracy.

MAFLD progression contributes to altered thalamus metabolism and brain structure

Metabolic associated fatty liver disease (MAFLD), commonly known as non-alcoholic fatty liver disease, represents a continuum of events characterized by excessive hepatic fat accumulation which can progress to nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and in some severe cases hepatocellular carcinoma. MAFLD might be considered as a multisystem disease that affects not only the liver but involves wider implications, relating to several organs and systems, the brain included. The present study aims to investigate changes associated with MAFLD-induced alteration of thalamic metabolism in vivo. DIAMOND (Diet-induced animal model of non-alcoholic fatty liver disease) mice were fed a chow diet and tap water (NC NW) or fat Western Diet (WD SW) for up to 28 weeks. At the baseline and weeks 4, 8, 20, 28 the thalamic neurochemical profile and total cerebral brain volume were evaluated longitudinally in both diet groups using ¹H-MRS. To confirm the disease progression, at each time point, a subgroup of animals was sacrificed, the livers excised and placed in formalin. Liver histology was assessed and reviewed by an expert liver pathologist. MAFLD development significantly increases the thalamic levels of total N-acetylaspartate, total creatine, total choline, and taurine. Furthermore, in the WD SW group a reduction in total cerebral brain volume has been observed (p < 0.05 vs NC NW). Our results suggest that thalamic energy metabolism is affected by MAFLD progression. This metabolic imbalance, that is quantifiable by ¹H-MRS in vivo, might cause structural damage to brain cells and dysfunctions of neurotransmitter release.

Volumetric Magnetic Resonance Imaging Study of Brain and Cerebellum in Children with Cerebral Palsy

Introduction. Quantitative magnetic resonance imaging (MRI) studies are rarely used in the diagnosis of patients with cerebral palsy. The aim of present study was to assess the relationships between the volumetric MRI and clinical findings in children with cerebral palsy compared to control subjects. Materials and Methods. Eighty-two children with cerebral palsy and 90 age- and sex-matched healthy controls were collected. Results. The dominant changes identified on MRI scans in children with cerebral palsy were periventricular leukomalacia (42%) and posthemorrhagic hydrocephalus (21%). The total brain and cerebellum volumes in children with cerebral palsy were significantly reduced in comparison to controls. Significant grey matter volume reduction was found in the total brain in children with cerebral palsy compared with the control subjects. Positive correlations between the age of the children of both groups and the grey matter volumes in the total brain were found. Negative relationship between width of third ventricle and speech development was found in the patients. Positive correlations were noted between the ventricles enlargement and motor dysfunction and mental retardation in children with cerebral palsy. Conclusions. By using the voxel-based morphometry, the total brain, cerebellum, and grey matter volumes were significantly reduced in children with cerebral palsy.

A diagnostic approach for cerebral palsy in the genomic era

An ongoing challenge in children presenting with motor delay/impairment early in life is to identify neurogenetic disorders with a clinical phenotype, which can be misdiagnosed as cerebral palsy (CP). To help distinguish patients in these two groups, conventional magnetic resonance imaging of the brain has been of great benefit in "unmasking" many of these genetic etiologies and has provided important clues to differential diagnosis in others. Recent advances in molecular genetics such as chromosomal microarray and next-generation sequencing have further revolutionized the understanding of etiology by more precisely classifying these disorders with a molecular cause. In this paper, we present a review of neurogenetic disorders masquerading as cerebral palsy evaluated at one institution. We have included representative case examples children presenting with dyskinetic, spastic, and ataxic phenotypes, with the intent to highlight the time-honored approach of using clinical tools of history and examination to focus the subsequent etiologic search with advanced neuroimaging modalities and molecular genetic tools. A precise diagnosis of these masqueraders and their differentiation from CP is important in terms of therapy, prognosis, and family counseling. In summary, this review serves as a continued call to remain vigilant for current and other to-be-discovered neurogenetic masqueraders of cerebral palsy, thereby optimizing care for patients and their families.

Classification systems in cerebral palsy

Because of increasing interest in conducting large-scale, multicenter investigations into the epidemiology of cerebral palsy and its prevention and treatment, efforts have been made to establish a standard definition and classification systems for cerebral palsy. In recent years there has also been increased focus on measurement of functional status of patients and new classifications for gross and fine motor function have been developed. The purpose of this article is to update the orthopaedic community on the current classification systems for patients with cerebral palsy. This information will be of value to surgeons in determining patients' suitability for certain treatments and will also assist them in reviewing current literature in cerebral palsy.

An age and gender dependency of metabolite concentrations in basal ganglia in children with spastic diplegia: proton magnetic resonance spectroscopy study

We determined metabolite profile in spastic diplegic children compared to controls in left basal ganglia of brain in using proton magnetic resonance spectroscopy in correlation with age and gender. Twenty-four patients with spastic diplegia and twenty-six healthy children were examined. The relative concentrations of N-acetylaspartate, choline, and myoinositol were measured in relation to creatine and different combinations of metabolites within 8-cm(3) brain voxel. Children with spastic diplegia showed reduced ratios of N-acetylaspartate/creatine, N-acetylaspartate/ choline, and N-acetylaspartate/myoinositol in the basal ganglia compared to the control group. Patients and controls subjects demonstrated a significant age-dependent increase in N-acetylaspartate/creatine, N-acetylaspartate/choline in the basal ganglia. No gender-dependent difference was shown in children with cerebral palsy for all tested metabolite ratios. Gender-related differences because of increased ratio N-acetylaspartate/choline in girls in controls were detected. These results indicate that maturation of brain exists in cerebral palsy and healthy children to a higher degree in healthy children.

Cerebral palsy

Cerebral palsy (CP) is a group of disorders of movement and posture resulting from nonprogressive disturbances of the fetal or neonatal brain. More than 80% of cases of CP in term infants originate in the prenatal period; in premature infants, both prenatal or postnatal causes contribute. The most prevalent pathological lesion seen in CP is periventricular white matter injury (PWMI) resulting from vulnerability of the immature oligodendrocytes (pre-OLs) before 32 wk of gestation. PWMI is responsible for the spastic diplegia form of CP and a spectrum of cognitive and behavioral disorders. Oxidative stress and excitotoxicity resulting from excessive stimulation of ionotropic glutamate receptors on preOLs are the most prominent molecular mechanisms for PWMI. Asphyxia around the time of birth in term infants accounts for less than 15% of CP in developed countries but the incidence is higher in underdeveloped areas. Asphyxia causes a different pattern of brain injury and CP than is seen after preterm injuries. This type of CP is associated with the clinical syndrome of hypoxic-ischemic encephalopathy shortly after the insult, and the cortex, basal ganglia, and brainstem are selectively vulnerable to injury. Experimental models indicate that neurons in the neonatal brain are more likely to die by delayed apoptosis extending over days to weeks than those in the adult brain. Neurons die by glutamate-mediated excitotoxicity involving downstream caspase-dependent and caspase-independent cell death pathways. Recent reports indicate that males and females preferentially utilize different pathways. Clinical trials indicate that mild hypothermia reduces death or disability in term infants following asphyxia and basic research suggests that this approach might be combined with pharmacological strategies in the future.

Clinical and neuroimaging profile of congenital brain malformations in children with spastic cerebral palsy

PURPOSE

Analysis of the incidence of congenital brain malformations in children with spastic cerebral palsy (CP) in a hospital-based study.

MATERIAL AND METHODS

The present study included 74 boys and 56 girls with spastic tetraplegia, diplegia, and hemiplegia CP. Magnetic resonance imaging MRI findings were analyzed in children with CP.

RESULTS

Significant abnormalities relevant to the CP were evident on MRI in 124 (95.3%) subjects. Periventicular leukomalacia (PVL) was detected more frequently in children with spastic diplegia than in patients with tetraplegia or hemiplegia. Cerebral atrophy was found more often in the tetraplegic group compared to the diplegic patients. Porencephalic cysts were detected more often in children with spastic hemiplegia. Congenital brain anomalies were evident in 15 (10.7%) children with spastic CP. Brain malformations included: schizencephaly (5), agenesis corpus callosum (4), polymicrogyria (2), holoprosencephaly (2) and lissencephaly (2). Intractable epilepsy and mental retardation were observed more often in children with brain anomalies. Twelve patients with congenital brain malformations were born at term and three born at preterm.

CONCLUSIONS

Neuroimaging results in children with CP may help determine the etiology and make better prognosis of CP.

Diffusion tensor imaging in children with periventricular leukomalacia: variability of injuries to white matter tracts

BACKGROUND AND PURPOSE

Conventional MR imaging shows evidence of brain injury and/or maldevelopment in 70%-90% of children with cerebral palsy (CP), though its capability to identify specific white matter tract injury is limited. The great variability of white matter lesions in CP already demonstrated by postmortem studies is thought to be one of the reasons why response to treatment is so variable. Our hypothesis is that diffusion tensor imaging (DTI) is a suitable technique to provide in vivo characterization of specific white matter tract lesions in children with CP associated with periventricular leukomalacia (PVL).

MATERIALS AND METHODS

In this study, 24 children with CP associated with PVL and 35 healthy controls were evaluated with DTI. Criteria for identification of 26 white matter tracts on the basis of 2D DTI color-coded maps were established, and a qualitative scoring system, based on visual inspection of the tracts in comparison with age-matched controls, was used to grade the severity of abnormalities. An ordinal grading system (0=normal, 1=abnormal, 2=severely abnormal or absent) was used to score each white matter tract.

RESULTS

There was marked variability in white matter injury pattern in patients with PVL, with the most frequent injury to the retrolenticular part of the internal capsule, posterior thalamic radiation, superior corona radiata, and commissural fibers.

CONCLUSION

DTI is a suitable technique for in vivo assessment of specific white matter lesions in patients with PVL and, thus, a potentially valuable diagnostic tool. The tract-specific evaluation revealed a family of tracts that are highly susceptible in PVL, important information that can potentially be used to tailor treatment options in the future.

Spastic cerebral palsy: clinical magnetic resonance imaging correlation of 129 children

A prospective study was undertaken of 129 children with spastic cerebral palsy to clarify the relationship between magnetic resonance imaging (MRI) findings and clinical features of cerebral palsy. Low birth weight, asphyxia, prematurity, seizures, mental development, Gross Motor Function Classification System, and MRI findings were analyzed. Significant abnormalities relevant to the cerebral palsy were evident on imaging in 123 (95.3%). A similar percentage of MRI abnormalities were detected in the groups, 45 (100%) in patients with tetraplegic cerebral palsy, 37 (92.5%) in children with diplegic cerebral palsy, and 42 (95.4%) with hemiplegic cerebral palsy. Periventricular leukomalacia was detected more frequently in the children with spastic diplegia than in the patients with tetraplegia or hemiplegia. Cerebral atrophy was found more often in the tetraplegic group compared to the diplegic patients. Porencephalic cysts were detected more frequently in children with spastic hemiplegia. Congenital brain anomalies were found in a higher proportion in tetraplegic children. Significant correlations between the MRI findings and Gross Motor Function Classification System in the diplegic and tetraplegic patients were found. No correlations between the MRI results and risk factors for cerebral palsy in the tetraplegic patients were noted. Early detection of brain abnormalities in children with cerebral palsy may help in the prognosis and in the initiation of appropriate therapy

Metabolite profile in the basal ganglia of children with cerebral palsy: a proton magnetic resonance spectroscopy study

This prospective study determined metabolite profile in the left and right basal ganglia of children with spastic cerebral palsy (CP) compared with children without disabilities, by using proton magnetic resonance spectroscopy (1HMRS). Twenty-three patients with spastic CP (12 males, 11 females; mean age 11y 9mo [SD 4y 2mo], range 4-17y) were examined. Twenty children had spastic diplegia and three had quadriplegia. Twenty-four normally developing children (13 females, 11 males; mean age 10y 3mo [SD 4y 8mo], range 4-17y) served as a comparison group. The relative concentrations of N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), and gamma-aminobutyric acid (GABA) were measured relative to creatine (Cr) and different combinations of metabolites within 8cm3 brain voxels. Children with CP showed reduced ratios of NAA:Cr, NAA:Cho, NAA:mI, and GABA:Cr in the basal ganglia relative to a matched comparison group. Patients demonstrated a significant age-dependent increase in NAA:Cr and NAA:Cho in the basal ganglia. No sex-dependent difference was shown in children with CP nor in the comparison group for all tested metabolite ratios. Significant correlation between Apgar score and ratio of mI:Cr in the group with CP was found. None of the tested metabolite ratios were correlated with the severity scale of CP in children with CP. NAA:Cr ratios were negatively correlated with learning disability in patients with CP. Results indicate the association of the metabolite ratios in basal ganglia with learning disability.

Neuroimaging in cerebral palsy: Patterns of brain dysgenesis and injury

Despite advances in obstetric and neonatal care, the overall prevalence of cerebral palsy has remained stable, supporting the belief that pathogenesis is primarily due to prenatal brain dysgenesis and injury. Neuroimaging studies have consistently shown abnormalities in 70% to 90% of affected children, facilitating clinical classification into groups with early brain malformations, white-matter injury, neonatal encephalopathies, and a heterogeneous group of postnatally acquired disorders. White-matter injury, well seen on conventional magnetic resonance imaging (MRI), is the leading cause of cerebral palsy in children born preterm. As many as 20% of very low birthweight infants have cystic and/or diffuse white-matter injury, termed periventricular leukomalacia, with evidence of associated pathology in other cortical and subcortical structures. In the group with acute, term perinatal pathology, a variety of imaging modalities, in addition to MRI, have diagnostic utility. In general, when added to conventional MRI, advanced techniques, such as diffusion tensor imaging, diffusion-weighted imaging, and magnetic resonance spectroscopy, provide a more complete picture of structural and functional brain abnormalities. The results have led to improved understanding of pathogenesis, especially in regard to periventricular leukomalacia and hypoxic-ischemic encephalopathy. This information might lead to interventions preventing brain injury in preterm infants and asphyxiated term newborns.

Neuroimaging in cerebral palsy

Parents and clinicians concerned about high-risk infants and children with motor delay or cerebral palsy seek information on cause, treatment, prognosis, and recurrence risk. Used in combination with history and examination, neuroimaging studies can improve diagnosis and management. In premature infants, cranial ultrasound is a reliable, noninvasive diagnostic modality. Nuclear magnetic resonance techniques including magnetic resonance imaging and diffusion weighted imaging can be used effectively in neonatal encephalopathies. In children with motor delay and cerebral palsy syndromes including spastic diplegia, quadriplegia, hemiplegia, and extrapyramidal movement disorders, conventional magnetic resonance imaging has become an important determinant of diagnosis and management. The aim of this article is to help clinicians select and interpret imaging studies of benefit in clinical care.