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Int. j. morphol ; 40(6): 1594-1601, dic. 2022. ilus, tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1421826


SUMMARY: Anatomy education has gathered together a great many of many new modalities and was modified from classical lecture-based and laboratory practice system to the blended modules. In the scope of the present study, we develop a new, practical, cost- effective and efficient three dimensional (3D) educational model, which aimed to be helpful for the detection and better understanding of basic neuroanatomy education. Tractographic imaging, fiber dissection, microscopic anatomy and plastination techniques were applied to the white matter regions of the two brains. After the photographs that were taken were converted to 3D images, the specimens were plastinated. By way of establishing an educational model as a whole, we applied it to 202 second-year medical students. The students were separated into two groups when they attended to the theoretical lecture. Group 1 took the classical laboratory education; on the other hand, Group 2 received the newly designed educational model. Pre and post-tests were introduced to each group before and after laboratory sessions, respectively. The success scores were put to comparison. The average achievement scores of each group showed increase significantly (p<0.05) after the laboratory sessions, besides the increase in the post-test results of Group 2 was more statistically significant (p<0.05). Consequently, this new educational model enriched by newly designed unified methods could be regarded as useful for grasping and improving the basic neuroanatomy knowledge.

La educación en anatomía ha reunido una gran cantidad de nuevas modalidades, modificándose el sistema clásico de la práctica del laboratorio y de las clases basadas en conferencias, hacia los módulos combinados. En el ámbito del presente estudio, desarrollamos un modelo educativo tridimensional (3D) nuevo, práctico, rentable y eficiente, que pretendía ser útil para la detección y una mejor comprensión de la educación básica en neuroanatomía. Se tomaron imágenes tractográficas, disección de fibras, anatomía microscópica y técnicas de plastinación en los cerebros. Después de convertir las fotografías que se tomaron en imágenes 3D, se plastinaron los especímenes. A modo de establecer un modelo educativo en su conjunto, lo aplicamos a 202 estudiantes de segundo año de medicina. Los estudiantes fueron separados en dos grupos cuando asistieron a la clase teórica. El Grupo 1 tomó la educación clásica de laboratorio; por su parte, el Grupo 2 recibió el nuevo modelo educativo diseñado para el estudio. Se introdujeron pruebas previas y posteriores a cada grupo, antes y después de las sesiones de laboratorio. Se compararon las puntuaciones. Los puntajes promedio de rendimiento de cada grupo mostraron un aumento significativo (p<0,05) después de las sesiones de laboratorio. Además, se obtuvo un aumento en los resultados positivos, posteriores a la prueba del Grupo 2, siendo estadísticamente significativo (p<0,05). En consecuencia, este modelo educativo, enriquecido por métodos unificados de nuevo diseño, podría considerarse útil para captar y mejorar los conocimientos básicos de neuroanatomía.

Humans , Models, Educational , Education, Medical/methods , Neuroanatomy/education , Dissection , Cerebrum/anatomy & histology , Diffusion Tensor Imaging , White Matter/anatomy & histology , Plastination , Microscopy , Nerve Fibers
Neuroscience Bulletin ; (6): 181-199, 2022.
Article in English | WPRIM | ID: wpr-922672


The glymphatic system plays a pivotal role in maintaining cerebral homeostasis. Chronic cerebral hypoperfusion, arising from small vessel disease or carotid stenosis, results in cerebrometabolic disturbances ultimately manifesting in white matter injury and cognitive dysfunction. However, whether the glymphatic system serves as a potential therapeutic target for white matter injury and cognitive decline during hypoperfusion remains unknown. Here, we established a mouse model of chronic cerebral hypoperfusion via bilateral common carotid artery stenosis. We found that the hypoperfusion model was associated with significant white matter injury and initial cognitive impairment in conjunction with impaired glymphatic system function. The glymphatic dysfunction was associated with altered cerebral perfusion and loss of aquaporin 4 polarization. Treatment of digoxin rescued changes in glymphatic transport, white matter structure, and cognitive function. Suppression of glymphatic functions by treatment with the AQP4 inhibitor TGN-020 abolished this protective effect of digoxin from hypoperfusion injury. Our research yields new insight into the relationship between hemodynamics, glymphatic transport, white matter injury, and cognitive changes after chronic cerebral hypoperfusion.

Animals , Mice , Brain Ischemia , Carotid Stenosis/drug therapy , Cognitive Dysfunction/etiology , Digoxin , Disease Models, Animal , Mice, Inbred C57BL , White Matter
Arq. neuropsiquiatr ; 79(12): 1084-1089, Dec. 2021. graf
Article in English | LILACS | ID: biblio-1355706


ABSTRACT Background: Although epilepsy is primarily known as a cortical disorder, there is growing body of research demonstrating white matter alterations in patients with epilepsy. Objective: To investigate the prevalence of white matter hyperintensities (WMH) and its association with seizure characteristics in patients with epilepsy. Methods: The prevalence of WMH in 94 patients with epilepsy and 41 healthy controls were compared. Within the patient sample, the relationship between the presence of WMH and type of epilepsy, frequency of seizures, duration of disease and the number of antiepileptic medications were investigated. Results: The mean age and sex were not different between patients and healthy controls (p>0.2). WMH was present in 27.7% of patients and in 14.6% of healthy controls. Diagnosis of epilepsy was independently associated with the presence of WMH (ß=3.09, 95%CI 1.06-9.0, p=0.039). Patients with focal epilepsy had higher prevalence of WMH (35.5%) than patients with generalized epilepsy (14.7%). The presence of WMH was associated with older age but not with seizure characteristics. Conclusions: WMH is more common in patients with focal epilepsy than healthy controls. The presence of WMH is associated with older age, but not with seizure characteristics.

RESUMO Antecedentes: Embora a epilepsia seja principalmente conhecida como um distúrbio cortical, há um crescente corpo de pesquisas que demonstra alterações na substância branca em pacientes com epilepsia. Objetivo: Investigar a prevalência de hiperintensidades da substância branca (WMH) e sua associação com características das crises em pacientes com epilepsia. Métodos: A prevalência de WMH em 94 pacientes com epilepsia e 41 controles saudáveis ​​foi comparada. Na amostra de pacientes, foi investigada a relação entre a presença de WMH e o tipo de epilepsia, a frequência das crises, a duração da doença e o número de medicamentos antiepilépticos. Resultados: A média de idade e o sexo não diferiram entre pacientes e controles saudáveis ​​(p>0,2). WMH estava presente em 27,7% dos pacientes, enquanto em 14,6% dos controles saudáveis. O diagnóstico de epilepsia foi independentemente associado à presença de WMH (ß=3,09, IC95% 1,06-9,0, p=0,039). Pacientes com epilepsia focal apresentaram maior prevalência de WMH (35,5%) do que pacientes com epilepsia generalizada (14,7%). A presença de WMH foi associada à idade avançada, mas não a características das crises. Conclusões: Pacientes com epilepsia focal têm WMH mais comum do que controles saudáveis. A presença de WMH está associada à idade avançada, mas não a características das crises epilépticas.

Humans , Aged , Epilepsy/drug therapy , Epilepsy/diagnostic imaging , White Matter/diagnostic imaging , Seizures/epidemiology , Seizures/diagnostic imaging , Magnetic Resonance Imaging
Rev. bras. neurol ; 57(3): 32-36, jul.-set. 2021.
Article in English | LILACS | ID: biblio-1342529


The extensive white matter of the brain, which comprises about one half of its volume, is constituted by an intricate and interwoven assemble of nerve fibers. The WMH (leukoaraiosis) represent the most frequent ischemic type of lesion of SVD, affecting the white matter. These lesions may be apparent or normal appearing on neuroimaging. In both cases such lesions may interrupt the affected white matter fibers, with consequent disconnection syndromes, and atrophy of the denervated grey matter structures. These conditions affect the structural neural networks (connectome), with functional repercussion on the cognitive and behavioral domains.

A extensa substância branca do cérebro, que compreende cerca da metade do seu volume, é constituída por um intricado e entrelaçado conjunto de fibras nervosas. As HSB (hiperintensidades da substância branca) (leucoaraiose) representam o mais frequente tipo de lesão isquêmica da DPV (doença dos pequenos vasos) que afeta a substância branca. Essas lesões podem ser aparentes ou de aparência normal na neuroimagem. Em ambos os casos tais lesões podem interromper essas fibras da substância branca, com consequente síndromes por desconexão e atrofia de estruturas de substância cinzenta desnervadas. Essas condições afetam as redes neurais estruturais (conectoma), com repercussão funcional nos domínios cognitivo e do comportamento.

Humans , Aged , Aged, 80 and over , White Matter/physiopathology , White Matter/diagnostic imaging , Magnetic Resonance Imaging/methods , Denervation , Leukoaraiosis/pathology
Rev. bras. neurol ; 57(2): 14-17, abr.-jun. 2021. tab, ilus
Article in English | LILACS | ID: biblio-1280778


The white matter hyperintensities (WMH, leucoaraiosis) represent the most common kind of ischemic vascular lesion of the white matter due to small vessel diseases, and occurs frequently in the elderly. Consequent to the neuroimaging identification arouse the need for their assessment. The group of Fazekas proposed a systematized semi-quantitative visual scale to score such lesions where two parameters were considered, extent and localization. The original scale was further modified, to a simplified version. Although other more complex scales have appeared, researchers remarked that the relatively simple Fazekas scale, in comparison to the complex ones and to volumetric measures, appeared to be sufficient when analyzing relationships between clinical parameters and WMH load in a clinical setting.

As hiperintensidades da substância branca (HSB, leucoaraiose) representam o tipo de lesão isquêmica mais comum da substância branca decorrente de doenças de pequenos vasos e ocorre frequentemente em idosos. Consequente à identificação por neuroimagem surgiu a necessidade de sua avaliação. O grupo de Fazekas propos uma escala visual semiquantitativa sistematizada para pontuar tais lesões, onde foram considerados dois parâmetros, extensão e localização. A escala original foi modificada para constituir uma versão mais simplificada. Embora outras escalas mais complexas tenham aparecido, pesquisadores comentaram que a relativamente simples escala de Fazekas, em comparação às mais complexas e a método volumétrico, mostrou-se suficiente quando é analisada a relação entre parâmetros clínicos e a carga de HSB em um cenário clínico.

Humans , Aged , Aged, 80 and over , Leukoaraiosis/pathology , Leukoaraiosis/diagnostic imaging , White Matter/diagnostic imaging , Aging , Brain Ischemia/diagnostic imaging , Neuroimaging/methods
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 43(2): 147-152, Mar.-Apr. 2021. tab
Article in English | LILACS | ID: biblio-1285532


Objective: The increased prevalence rate of white matter hyperintensities is one of the most consistently reported brain abnormalities in adults with bipolar disorder. However, findings in children and adolescents with bipolar disorder are less consistent. Prior studies have been constrained by small sample sizes and/or poor age- and sex-matching of healthy controls. We examined this topic in the largest sample of adolescents with bipolar disorder to date. Methods: T2-weighted 3-Tesla magnetic resonance imaging data were acquired for 83 adolescents with bipolar disorder diagnosed via the Kiddie Schedule for Affective Disorders and the Schizophrenia, Present and Lifetime version semi-structured interview and 64 age- and sex-matched healthy controls. All acquired scans were examined by neuroradiologists and the presence or absence of white matter hyperintensities was determined for each participant. Results: The prevalence of white matter hyperintensities did not differ between adolescents with bipolar disorder (13.3%) and controls (21.9%; χ2 = 1.90; p = 0.168). Conclusion: In contrast to the study hypothesis, the prevalence of white matter hyperintensities was not higher in adolescents with bipolar disorder than controls. The large sample size and good matching for age and sex bolster the reliability of this negative finding. Future studies are warranted to evaluate the prevalence, incidence, and predictors of white matter hyperintensities in early-onset bipolar disorder prospectively.

Humans , Child , Adolescent , Young Adult , Bipolar Disorder/epidemiology , Bipolar Disorder/diagnostic imaging , White Matter/diagnostic imaging , Brain/diagnostic imaging , Magnetic Resonance Spectroscopy , Prevalence , Reproducibility of Results
Med. leg. Costa Rica ; 38(1)mar. 2021.
Article in Spanish | LILACS-Express | LILACS, SaludCR | ID: biblio-1386273


Resumen La enfermedad de sustancia blanca representa una enfermedad poco común en usuarios que se apersonan al Organismo de Investigación Judicial, por este motivo al valorar un caso es necesario investigar los antecedentes de la medicina legal para establecer mecanismos causales con hechos representados en la sociedad. Además, es necesario abordar la enfermedad de sustancia blanca desde su aparición, incidencia, aspectos clínicos, hallazgos ante una posible autopsia, explorar el desarrollo de fisiopatología como indagar acerca de las formas de diagnosticar la enfermedad y valorar las opciones terapéuticas. Estos conocimientos son base para establecer una relación médico legal y analizar si el caso de una niña de 9 años tiene correlación con una historia de trauma en cabeza que no evidencia cambios inflamatorios, aumento de volumen de tejidos blandos o duros, excoriaciones, equimosis, hematomas, cicatrices, gradas o callos óseos y con valoraciones médicas que indican tetraparesia flácida en ausencia de hallazgos patológicos al reporte de tomografía axial computarizada y resonancia magnética de columna cervicodorsal.

Abstract White matter disease represents a rare disease in users who go to the Organismo de Investigación Judicial (Judicial Investigation Agency) for this reason, when evaluating a case, it is necessary to investigate the antecedents of legal medicine to establish causal mechanisms with facts represented in society. In addition, it is necessary to address white matter disease from its appearance, incidence, clinical aspects, findings in a possible autopsy, explore the development of pathophysiology such as inquire about ways to diagnose the disease, and assess therapeutic options. This knowledge is the basis for establishing a legal medical relationship and analyzing whether the case of a 9-year-old girl has a correlation with a history of head trauma that does not show inflammatory changes, increased soft or hard tissue volume, excoriations, bruising, bruising. , scars, bleachers or calluses and with medical evaluations that indicate flaccid tetraparesis in the absence of pathological findings on the report of computed tomography and magnetic resonance imaging of the cervicodorsal spine.

Humans , Female , Child, Preschool , Leukoencephalopathies , White Matter , Costa Rica
Frontiers of Medicine ; (4): 125-138, 2021.
Article in English | WPRIM | ID: wpr-880937


This study aimed to define the most consistent white matter microarchitecture pattern in Parkinson's disease (PD) reflected by fractional anisotropy (FA), addressing clinical profiles and methodology-related heterogeneity. Web-based publication databases were searched to conduct a meta-analysis of whole-brain diffusion tensor imaging studies comparing PD with healthy controls (HC) using the anisotropic effect size-signed differential mapping. A total of 808 patients with PD and 760 HC coming from 27 databases were finally included. Subgroup analyses were conducted considering heterogeneity with respect to medication status, disease stage, analysis methods, and the number of diffusion directions in acquisition. Compared with HC, patients with PD had decreased FA in the left middle cerebellar peduncle, corpus callosum (CC), left inferior fronto-occipital fasciculus, and right inferior longitudinal fasciculus. Most of the main results remained unchanged in subgroup meta-analyses of medicated patients, early stage patients, voxel-based analysis, and acquisition with 30 diffusion directions. The subgroup meta-analysis of medication-free patients showed FA decrease in the right olfactory cortex. The cerebellum and CC, associated with typical motor impairment, showed the most consistent FA decreases in PD. Medication status, analysis approaches, and the number of diffusion directions have an important impact on the findings, needing careful evaluation in future meta-analyses.

Humans , Anisotropy , Brain/diagnostic imaging , Corpus Callosum , Diffusion Tensor Imaging , Parkinson Disease/diagnostic imaging , White Matter/diagnostic imaging
Article in Chinese | WPRIM | ID: wpr-879282


Diffusion tensor imaging technology can provide information on the white matter of the brain, which can be used to explore changes in brain tissue structure, but it lacks the specific description of the microstructure information of brain tissue. The neurite orientation dispersion and density imaging make up for its shortcomings. But in order to accurately estimate the brain microstructure, a large number of diffusion gradients are needed, and the calculation is complex and time-consuming through maximum likelihood fitting. Therefore, this paper proposes a kind of microstructure parameters estimation method based on the proximal gradient network, which further avoids the classic fitting paradigm. The method can accurately estimate the parameters while reducing the number of diffusion gradients, and achieve the purpose of imaging quality better than the neurite orientation dispersion and density imaging model and accelerated microstructure imaging via convex optimization model.

Brain/diagnostic imaging , Diffusion Magnetic Resonance Imaging , Diffusion Tensor Imaging , Neurites , White Matter
Article in Chinese | WPRIM | ID: wpr-879868


OBJECTIVE@#To study the effect of human oligodendrocyte precursor cell (hOPC) transplantation in the treatment of white matter injury (WMI).@*METHODS@#Neonatal rats were randomly divided into a sham-operation group, a model group, and a transplantation group (@*RESULTS@#The place navigation test using the Morris water maze showed that the model group had a significantly longer escape latency than the sham-operation group, and compared with the model group, the transplantation group had a significant reduction in escape latency (@*CONCLUSIONS@#Intrathecal hOPC transplantation may alleviate neurological injury and promote remyelination in a rat model of WMI.

Animals , Humans , Rats , Animals, Newborn , Myelin Sheath , Oligodendrocyte Precursor Cells , Oligodendroglia , White Matter
Article in Chinese | WPRIM | ID: wpr-879850


OBJECTIVE@#To study the effect of different melatonin treatment regimens on long-term behavior and white matter damage in neonatal rats with hypoxic-ischemic brain damage (HIBD), and to seek an optimal melatonin treatment regimen.@*METHODS@#Healthy Sprague-Dawley rats, aged 7 days, were randomly divided into four groups: sham-operation, HIBD, single-dose immediate treatment (SDIT), and 7-day continuous treatment (7DCT), with 8 rats in each group. A neonatal rat model of HIBD was prepared according to the classical Rice-Vannucci method. On day 21 after HIBD, the Morris water maze test was used to evaluate spatial learning and memory abilities. On day 70 after HIBD, immunofluorescence assay was used to measure the expression of neuronal nuclear antigen (NeuN) in the cerebral cortex and the hippocampal CA1 region of neonatal rats, and double-label immunofluorescence was used to measure the expression of myelin basic protein (MBP) and neurofilament 200 (NF200) in the corpus striatum and the corpus callosum.@*RESULTS@#The results of the Morris water maze test showed that the SDIT and 7DCT groups had a significantly shorter mean escape latency than the HIBD group, and the 7DCT group had a significantly shorter mean escape latency than the SDIT group (@*CONCLUSIONS@#Both SDIT and 7DCT can improve long-term behavior and reduce white matter damage in neonatal rats with HIBD, and 7DCT is more effective than SDIT.

Animals , Rats , Animals, Newborn , Hypoxia-Ischemia, Brain/drug therapy , Melatonin/pharmacology , Rats, Sprague-Dawley , White Matter
Acta Physiologica Sinica ; (6): 407-422, 2021.
Article in Chinese | WPRIM | ID: wpr-887677


As the two essential components, the white matter and gray matter compose the central nervous system of the brain. Widely known that axons of neurons mainly form the white matter, and these formed nerve fibers are responsible for transmitting information among various brain regions to achieve the coordinated operation of the entire brain. Early research on the white matter could only be done by dissecting living animals or human cadavers, until Basser et al. proposed diffusion tensor imaging (DTI) technology in 1994, which could detect the diffusion characteristics of water in the brain in vivo noninvasively. Accordingly, this technology could be applied to investigate the diffusion movement of water in white matter to obtain the information of direction and micro-anatomy of white matter fiber bundles. With the advancement on the display and analysis of the anatomical structure of white matter fiber bundles, the exploration of microscopic pathological changes, and the assistance of clinical diagnosis and neurophysiological research, DTI technology has become one of the most popular topics in brain science research. Chronic pain refers to pain lasting more than three months, which not only seriously affects the patient's physical and social functions, but also dramatically reduces the quality of life. It was reported that long-term pain stimulation might cause pathological remodeling of the central nervous system, and abnormalities in white matter were found in imaging examinations of patients with chronic pain. This review introduces the quantitative analysis methods of white matter fiber bundle microstructure based on DTI and its application in chronic pain, and further discusses the application value of DTI technology on clinical research of chronic pain.

Animals , Humans , Brain , Chronic Pain/diagnostic imaging , Diffusion Tensor Imaging , Quality of Life , White Matter/diagnostic imaging
Article in English | WPRIM | ID: wpr-922587


OBJECTIVES@#White matter hyperintensity (WMH) is an important factor leading to cognitive impairment, and the mechanism has not been clarified. In recent years, studies have found that circular RNA (circRNA) has differential expression in cerebrovascular diseases. This study aims to analyze the expression profile of circRNA in peripheral blood mononuclear cell (PBMC) of patients with WMH with cognitive impairment, to screen the differentially expressed circRNA, and to explore the possible role of circRNA in WMH with cognitive impairment.@*METHODS@#CircRNA microarray was used to detect the circRNA expression profile of PBMC in patients with WMH with cognitive impairment, and in patients with WMH without cognitive impairment as well as in normal controls (3 cases each, male to female ratio of 2꞉1). The differentially expressed circRNA in patients with WMH with cognitive impairment was screened. The screening criteria for differentially expressed circRNA was fold change (FC) ≥2.0 (|log@*RESULTS@#Compared with the control group, there were 5 significantly up-regulated circRNA and 3 down-regulated circRNA in the WMH with cognitive impairment group; 8 circRNA were significantly up-regulated and 2 were down-regulated in the WMH without cognitive impairment group. When compared with the WMH with cognitive impairment group, no co-differentially expressed circRNA was found in WMH without cognitive impairment group and control group. Compared with the control group, the expression of hsa_circ_0092222 was up-regulated and the expressions of hsa_circ_0000662 and hsa_circ_0083773 were down-regulated in the WMH with cognitive impairment group and the WMH without cognitive impairment group, and there was no significant difference between the 2 groups (all @*CONCLUSIONS@#The circRNA expression profile of patients with WMH is changed significantly. The differentially expressed circRNA may be the cause of WMH; Hsa_circ_0092222, hsa_circ_0000662, and hsa_circ_0083773 may regulate the expression of target genes by targeting adsorption of the target miRNA, leading to brain white matter damage through Janus kinase 2 (JAK2)/signal transducers and activators of transcription (STAT3) signal pathway and Wnt signal pathway.There is no significant difference in circRNA expression profile between WMH with or without cognitive impairment. Cognitive impairment in patients with WMH may have other reasons.

Female , Humans , Male , Cognitive Dysfunction/genetics , Leukocytes, Mononuclear , MicroRNAs , RNA/genetics , RNA, Circular , Software , White Matter
Frontiers of Medicine ; (4): 887-902, 2021.
Article in English | WPRIM | ID: wpr-922517


Monocarboxylic acid transporter 1 (MCT1) maintains axonal function by transferring lactic acid from oligodendrocytes to axons. Subarachnoid hemorrhage (SAH) induces white matter injury, but the involvement of MCT1 is unclear. In this study, the SAH model of adult male Sprague-Dawley rats was used to explore the role of MCT1 in white matter injury after SAH. At 48 h after SAH, oligodendrocyte MCT1 was significantly reduced, and the exogenous overexpression of MCT1 significantly improved white matter integrity and long-term cognitive function. Motor training after SAH significantly increased the number of ITPR2

Animals , Male , Rats , MicroRNAs/genetics , Monocarboxylic Acid Transporters/genetics , Rats, Sprague-Dawley , Subarachnoid Hemorrhage , Symporters/genetics , White Matter/injuries
Article in Chinese | WPRIM | ID: wpr-828679


OBJECTIVE@#To study the value of fractional anisotropy (FA) of regions of interest (ROI) on magnetic resonance diffusion tensor imaging (DTI) in bilirubin-induced neurological dysfunction in neonates.@*METHODS@#A total of 91 neonates with hyperbilirubinemia who were hospitalized from January 2017 to January 2018 were enrolled. According to the peak level of total serum bilirubin, they were divided into three groups: mild/moderate increase (n=45), severe increase (n=35), and extremely severe increase (n=11). According to the presence or absence of abnormal neurological manifestations, they were divided into two groups: neurological dysfunction (n=20) and non-neurological dysfunction (n=71). Ten healthy full-term infants were enrolled as the control group. Head DTI was performed for all neonates to measure the FA values of the bilateral globus pallidus, the anterior limb of the internal capsule, the posterior limb of the internal capsule, and the cerebellar dentate nucleus.@*RESULTS@#The extremely severe increase group had significantly lower FA values of the globus pallidus than the control, mild/moderate increase, and severe increase groups (P<0.05). The severe increase group had significantly lower FA values of the globus pallidus than the control group (P<0.05). The extremely severe increase group had significantly lower FA values of the posterior limb of the internal capsule than the control, mild/moderate increase, and severe increase groups (P<0.05). The neurological dysfunction group had significantly lower FA values of the globus pallidus and the posterior limb of the internal capsule than the non-neurological dysfunction group (P<0.05).@*CONCLUSIONS@#Serum bilirubin level combined with the changes in the DTI FA values of the globus pallidus and the posterior limb of the internal capsule can be used to predict the injury of cerebral nuclei and white matter fibers.

Humans , Infant, Newborn , Anisotropy , Bilirubin , Brain , Diffusion Magnetic Resonance Imaging , Diffusion Tensor Imaging , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , White Matter
Article in Chinese | WPRIM | ID: wpr-942185


OBJECTIVE@#To construct and verify a standard template of white matter based on Chinese normal 0 to 2 years old infants by using nonlinear high registration accuracy of non-rigid diffeomorphism paradigm (large deformation diffeomorphic metric mapping, LDDMM).@*METHODS@#Full-term spontaneous labor children without maternal pregnancy disease (hypertension, diabetes, etc.), intrauterine hypoxia and ischemia, head trauma, intracranial infection, intracranial surgery history, family history of mental disorders were selected. Diffusion tensor imaging (DTI) data from the 120 normal Chinese infants under 2 years old were acquired after excluding the existence of neurological diseases revealed by neurologists, radiologists and Gesell Developmental Scale. All the data were divided into six groups including group A: 1 day to 1.5 months, group B: 1.5 to 4.5 months, group C: 4.5 to 9.0 months, group D: 9 to 15 months, group E: 15 to 21 months, and group F: 21 to 24 months. Data pre-processing, normalizing, tensor fitting and calculation of all the images were performed by using MRlcron, DtiStudio, DiffeoMap and SPM software package combined with LDDMM image registration method based on the selected single template of each group. And the average templates of each group were constructed by MATLAB software platform. The set of templates included fractional anisotropy figure (FA), color map, T1 weighted image, b0 image and the mean of all DWfs figures.@*RESULTS@#The templates of FA, T1, b0, DWfs and color map for the normal brain magnetic resonance white matter development of the Chinese infants aged 0 to 2 years were successfully established with the subjective scores exceeding 2 points. The objective evaluation root mean squared error was controlled below 0.19, and the cubic chart of brain alternation trend for the children aged 0 to 2 years was consistent with previous literature.@*CONCLUSION@#Constructing a standard template of white matter based on Chinese normal infants, by using nonlinear high registration accuracy of non-rigid diffeomorphism paradigm provides not only a foundation of further research on brain development, mechanism and treatment of pediatric diseases associated with brain, but also objective and fair imaging information for medical education and research.

Child , Child, Preschool , Humans , Infant , Infant, Newborn , Brain/diagnostic imaging , Diffusion Tensor Imaging , Image Processing, Computer-Assisted , Magnetic Resonance Spectroscopy , Software , White Matter/diagnostic imaging
Clinics ; 75: e2245, 2020. tab
Article in English | LILACS | ID: biblio-1142775


OBJECTIVES: Although a large number of studies have shown brain volumetric differences between men and women, only a few investigations have analyzed brain tissue volumes in representative samples of the general elderly population. We investigated differences in gray matter (GM) volumes, white matter (WM) volumes, and intracranial volumes (ICVs) between the sexes in individuals older than 66 years using structural magnetic resonance imaging (MRI). METHODS: Using FreeSurfer version 5.3, we obtained the ICVs and GM and WM volumes from the MRI datasets of 84 men and 92 women. To correct for interindividual variations in ICV, GM and WM volumes were adjusted with a method using the residuals of a least-square-derived linear regression between raw volumes and ICVs. We then performed an analysis of covariance comparing men and women, including age and years of schooling as confounding factors. RESULTS: Women had a lower socioeconomic status overall and fewer years of schooling than men. The comparison of unadjusted brain volumes showed larger GM and WM volumes in men. After the ICV correction, the adjusted volumes of GM and WM were larger in women. CONCLUSION: After the ICV correction and taking into account differences in socioeconomic status and years of schooling, our results confirm previous findings of proportionally larger GM in women, as well as larger WM volumes. These results in an elderly population indicate that brain volumetric differences between sexes persist throughout the aging process. Additional studies combining MRI and other biomarkers to identify the hormonal and molecular bases influencing such differences are warranted.

Humans , Male , Female , Aged , Brain/diagnostic imaging , White Matter , Magnetic Resonance Imaging , Linear Models , Gray Matter/diagnostic imaging
Medicina (B.Aires) ; 79(supl.3): 10-14, set. 2019. ilus
Article in Spanish | LILACS, BNUY, UY-BNMED | ID: biblio-1040542


Los nacimientos prematuros son uno de los principales indicadores de salud de un país. Están asociados a una alta mortalidad e importante morbilidad en niños con parálisis cerebral y otros trastornos del neurodesarrollo, incluyendo problemas cognitivos y del aprendizaje. Los principales tipos de lesión encefálica en los recién nacidos prematuros son: a) las lesiones de la sustancia blanca, generalmente asociadas a alteraciones neuronales y axonales en la corteza cerebral y otras zonas de sustancia gris; b) hemorragias intracraneanas que incluyen las de la matriz germinal, intraventriculares e intraparenquimatosas y c) del cerebelo. Las lesiones de sustancia blanca incluyen la leucomalacia periventricular quística, no quística (con focos de necrosis microscópicos) y lesiones difusas de sustancia blanca, no necróticas. Estas lesiones tienen múltiples factores etiológicos. Las características anatómicas y fisiológicas de las estructuras vasculares periventriculares predisponen a la sustancia blanca a ser muy vulnerable a las situaciones de isquemia cerebral y, en interacción con factores infecciosos/inflamatorios, activan a las microglías generando estrés oxidativo (por liberación de radicales libres del oxígeno y del nitrógeno), liberación de citoquinas proinflamatorias, liberación de glutamato, fallo energético y alteración de la integridad vascular. Todo lo anteriormente mencionado genera una particular vulnerabilidad de los pre-oligodendrocitos que termina alterando la mielinización. La hipoxia-isquemia también puede producir necrosis neuronal selectiva en diferentes regiones encefálicas. La matriz germinal es un área altamente vascularizada en la región subependimaria periventricular con una estructura capilar muy frágil que la predispone a las hemorragias.

Preterm birth is one of the main country health indicators. It is associated with high mortality and significant morbidity in preterm newborns with cerebral palsy and potential long-term neurodevelopmental disabilities like cognitive and learning problems. The main lesions could be: a) white matter injuries, generally associated with cortical and other regions of grey matter neuronal-axonal disturbances; b) intracranial hemorrhage that includes germinal matrix, intraventricular and parenchymal, c) cerebellum injuries. The white matter lesions include cystic and non-cystic (with microscopic focal necrosis) periventricular leukomalacia and non-necrotic diffuse white matter injury. Multiple etiologic factors are associated with these injuries. Anatomical and physiological characteristics of periventricular vascular structures predispose white matter to cerebral ischemia and, interacting with infection/inflammation factors, activate microglia, generating oxidative stress (mediated by free oxygen and nitrogen radicals), pro-inflammatory cytokine and glutamate toxicity, energetic failure and vascular integrity disturbances. All these factors lead to a particular vulnerability of pre-oligodendrocytes that will affect myelination. Hypoxia-ischemia also may produce selective neuronal necrosis in different cerebral regions. Germinal matrix is a highly vascularized zone beneath ependymal or periventricular region that constitutes a capillary bed with a particular structural fragility that predispose it to hemorrhage.

Humans , Infant, Newborn , Leukomalacia, Periventricular/etiology , Brain Injuries/etiology , Infant, Premature , Brain Ischemia/etiology , Cerebral Palsy/etiology , Hypoxia-Ischemia, Brain/etiology , Brain Injuries/mortality , Brain Injuries/diagnostic imaging , Brain Ischemia/mortality , Brain Ischemia/diagnostic imaging , Cerebral Palsy/mortality , Hypoxia-Ischemia, Brain/mortality , Hypoxia-Ischemia, Brain/diagnostic imaging , White Matter/pathology
Rev. argent. radiol ; 83(3): 95-101, set. 2019. ilus, tab
Article in Spanish | LILACS | ID: biblio-1057407


Objetivo Desde la aparición de la tractografía, al tratarse de una técnica no invasiva y que usa la ampliamente conocida resonancia magnética (RM), el estudio de la sustancia blanca se ha facilitado. A partir de eso, se han logrado grandes descubrimientos en cuanto a fascículos cerebrales involucrados en funciones cognitivas. Sin embargo, su evaluación sigue siendo subjetiva y depende de la experiencia y entrenamiento del evaluador, razón por la cual se ha limitado su aplicabilidad en la práctica clínica. En ese sentido, es conveniente parametrizar volúmenes cerebrales de sustancia blanca en población sana a través de una herramienta electrónica que se pueda reproducir y así poderlo aplicar en enfermos. Materiales y métodos Se reportan 10 sujetos sanos desde el punto de vista neurológico. Para cada sujeto, se adquirieron imágenes ponderadas por difusión y los resultados se visualizaron mediante FiberNavigator ( Finalmente, esa misma herramienta fue utilizada para purificar los fascículos objeto de estudio y realizar el conteo de las fibras. Resultados Se obtuvieron valores de volumetría del fascículo longitudinal superior (FLS), fascículo longitudinal inferior (FLI), fascículo frontoccipital inferior (FFI), fascículo uncinado (FU) y fascículo del cíngulo (FC), identificando que no existen diferencias estadísticamente significativas entre el número de fibras que componen los fascículos cerebrales. Discusión Los resultados alcanzados de la anatomía y la direccionalidad de fibras de los fascículos cerebrales de este estudio coinciden con el resto de la evidencia publicada hasta el momento, sin encontrar diferencias en cuanto a su organización y recorrido. Conclusión Aunque esos resultados no sirven como valores de referencia para ser aplicados en pacientes con patología neurológica, brindamos información inexistente hasta el momento, con ese equipo en específico y la reproducción entre los distintos usuarios y el software.

Objective Since the appearance of tractography, as it is a non-invasive technique and uses the widely known magnetic resonance (MR), the study of white matter has been facilitated. After this, great discoveries have been made regarding the brain fascicles involved in cognitive functions. However, its evaluation continues to be subjective and depends on the evaluator's experience and training. That the reason why its applicability has been limited in clinical practice. Because of this, it is convenient to parametrize cerebral volumes of white matter in healthy population through an electronic, reproducible tool that could be applied in patients. Materials and Methods Ten neurologically healthy subjects are reported, for each subject we acquired images weighted by diffusion and the results were visualized by means of FiberNavigator ( Finally, this same tool was used to purify the fascicles under study and perform the fiber count. Results Volumetric values of the upper longitudinal fasciculus, inferior longitudinal fasciculus, inferior frontoccipital fasciculus, uncinated fasciculus and cingulate fasciculus were obtained, identifying that there are not statistically significant differences in the number of fibers that make up the cerebral fascicles. Discussion The results achieved of the anatomical and fiber directionality of the cerebral fascicles of this study, coincide with the rest of the evidence published up to now, without finding differences regarding its organization and route. Conclusion Although these results do not serve as reference values to be applied in patients with neurological pathology, do we provide nonexistent information so far, with this specific equipment and the reproducibility between the different users and the software.

Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Cognition/physiology , White Matter/diagnostic imaging , Reference Values , Anisotropy , Titrimetry/standards , Diffusion Tensor Imaging/standards , Nerve Fibers