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1.
Neurosurg Rev ; 46(1): 175, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37450200

RESUMO

The aim of our pilot study was to compare the performance of the RS-MRI protocol combined with skull radiography versus CT for the detection of skull fractures, scalp hematomas, and intracranial hemorrhage in patients with abusive head trauma (AHT). Additionally, our study aimed to determine whether the presence of scalp hematoma predicts concurrent skull fracture. We conducted a pilot study through retrospective chart review of 24 patients between ages 0 and 15 months who experienced AHT and who received CT, MRI, and skull radiography between May 2020 and August 2021. Two blinded board certified neuroradiologists reviewed the skull radiographs alongside the rapid trauma MRI. Their impressions were documented and compared with findings derived from CT. Combination imaging detected ten out of the 12 skull fractures noted on CT (sensitivity 83.3%, specificity 100%, p=0.48). RS-MRI detected 15 out of the 16 intracranial hemorrhages detected by CT (sensitivity 93.75%, p >0.9). When scalp hematoma was detected on RS-MRI, nine out of the 12 had associated skull fractures when reviewed by radiologist 1 (sensitivity 75%, specificity 100%, p=0.22), and seven out of the 12 had associated skull fractures when reviewed by radiologist 2 (sensitivity 58%, specificity 92%, p=0.25). In pediatric patients with suspected AHT, we found that RS-MRI combined with skull radiographs was not significantly different than CT for the detection of skull fractures, scalp hematomas, and intracranial hemorrhage. This combination has the potential to replace the use of CT as a screening tool for abusive head trauma, while avoiding the risks of sedation often required for routine MRI.


Assuntos
Traumatismos Craniocerebrais , Fraturas Cranianas , Criança , Humanos , Lactente , Projetos Piloto , Estudos Retrospectivos , Traumatismos Craniocerebrais/diagnóstico por imagem , Radiografia , Tomografia Computadorizada por Raios X/métodos , Fraturas Cranianas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Hematoma , Hemorragias Intracranianas , Crânio
2.
Proc Natl Acad Sci U S A ; 117(38): 23904-23913, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32868436

RESUMO

Adult brains are functionally flexible, a unique characteristic that is thought to contribute to cognitive flexibility. While tools to assess cognitive flexibility during early infancy are lacking, we aimed to assess the spatiotemporal developmental features of "neural flexibility" during the first 2 y of life. Fifty-two typically developing children 0 to 2 y old were longitudinally imaged up to seven times during natural sleep using resting-state functional MRI. Using a sliding window approach, MR-derived neural flexibility, a quantitative measure of the frequency at which brain regions change their allegiance from one functional module to another during a given time period, was used to evaluate the temporal emergence of neural flexibility during early infancy. Results showed that neural flexibility of whole brain, motor, and high-order brain functional networks/regions increased significantly with age, while visual regions exhibited a temporally stable pattern, suggesting spatially and temporally nonuniform developmental features of neural flexibility. Additionally, the neural flexibility of the primary visual network at 3 mo of age was significantly and negatively associated with cognitive ability evaluated at 5/6 y of age. The "flexible club," comprising brain regions with neural flexibility significantly higher than whole-brain neural flexibility, were consistent with brain regions known to govern cognitive flexibility in adults and exhibited unique characteristics when compared to the functional hub and diverse club regions. Thus, MR-derived neural flexibility has the potential to reveal the underlying neural substrates for developing a cognitively flexible brain during early infancy.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Pré-Escolar , Cognição/fisiologia , Feminino , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Descanso/fisiologia
3.
Neuroimage ; 254: 119127, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35337965

RESUMO

Resting-state functional magnetic resonance imaging (rs-fMRI) is a non-invasive functional neuroimaging modality that has been widely used to investigate functional connectomes in the brain. Since noise and artifacts generated by non-neuronal physiological activities are predominant in raw rs-fMRI data, effective noise removal is one of the most important preprocessing steps prior to any subsequent analysis. For rs-fMRI denoising, a common trend is to decompose rs-fMRI data into multiple components and then regress out noise-related components. Therefore, various machine learning techniques have been used in such analyses with predefined procedures and manually engineered features. However, the lack of a universal definition of a noise-related source or artifact complicates manual feature engineering. Manual feature selection can result in the failure to capture unknown types of noise. Furthermore, the possibility that the hand-crafted features will only work for the broader population (e.g., healthy adults) but not for "outliers" (e.g., infants or subjects that belong to a disease cohort) is quite high. In practice, we have limited knowledge of which features should be extracted; thus, multi-classifier assembly must be implemented to improve performance, although this process is quite time-consuming. However, in real rs-fMRI applications, fast and accurate automatic identification of noise-related components on different datasets is critical. To solve this problem, we propose a novel, automatic, and end-to-end deep learning framework dedicated to noise-related component identification via a faster and more effective multi-layer feature extraction strategy that learns deeply embedded spatio-temporal features of the components. In this study, we achieved remarkable performance on various rs-fMRI datasets, including multiple adult rs-fMRI datasets from different rs-fMRI studies and an infant rs-fMRI dataset, which is quite heterogeneous and differs from that of adults. Our proposed framework also dramatically increases the noise detection speed owing to its inherent ability for deep learning (< 1s for single-component classification). It can be easily integrated into any preprocessing pipeline, even those that do not use standard procedures but depend on alternative toolboxes.


Assuntos
Conectoma , Imageamento por Ressonância Magnética , Adulto , Algoritmos , Artefatos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos
4.
Magn Reson Med ; 86(4): 1944-1955, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34009709

RESUMO

PURPOSE: Motion can strongly affect MRI image quality and derived imaging measures. We studied the effects of motion and retrospective motion correction (MC) on the visualization and quantitative measures of the perivascular space and penetrating vessel (PVSV) complex, an essential part of the glymphatic system, on high-resolution T2 -weighted MRI images at 7T. METHODS: MC was achieved by adjusting k-space data based on head positions measured using fat navigator images. PVSV visibility and quantitative measures including diameter, volume fraction (VF), count, and contrast were compared between images with and without MC. RESULTS: Without MC, VF, and count decreased significantly with increasing head rotation. MC improved PVSV visualization in all cases with severe motion artifacts. MC decreased diameter in white matter (WM) and increased VF, count, and contrast in basal ganglia and WM. The changes of VF, count, and contrast after MC strongly correlated with motion severity. MC eliminated the significant dependences of VF and count on rotation and reduced the inter-subject variations of VF and count. The effect sizes of age and breathing gas effects on VF and count, and contrast increased in most cases after MC, while those on diameter exhibited inconsistent behavior. CONCLUSIONS: Motion affects PVSV quantification without MC. MC improves PVSV visibility and increases the statistical power of detecting physiological PVSV VF, count, and contrast changes but may have limited benefits for increasing the power for detecting diameter changes.


Assuntos
Encéfalo , Processamento de Imagem Assistida por Computador , Artefatos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Movimento (Física) , Estudos Retrospectivos , Rotação
5.
Cereb Cortex ; 30(11): 5844-5862, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32572452

RESUMO

The aging process is accompanied by changes in the brain's cortex at many levels. There is growing interest in summarizing these complex brain-aging profiles into a single, quantitative index that could serve as a biomarker both for characterizing individual brain health and for identifying neurodegenerative and neuropsychiatric diseases. Using a large-scale structural covariance network (SCN)-based framework with machine learning algorithms, we demonstrate this framework's ability to predict individual brain age in a large sample of middle-to-late age adults, and highlight its clinical specificity for several disease populations from a network perspective. A proposed estimator with 40 SCNs could predict individual brain age, balancing between model complexity and prediction accuracy. Notably, we found that the most significant SCN for predicting brain age included the caudate nucleus, putamen, hippocampus, amygdala, and cerebellar regions. Furthermore, our data indicate a larger brain age disparity in patients with schizophrenia and Alzheimer's disease than in healthy controls, while this metric did not differ significantly in patients with major depressive disorder. These findings provide empirical evidence supporting the estimation of brain age from a brain network perspective, and demonstrate the clinical feasibility of evaluating neurological diseases hypothesized to be associated with accelerated brain aging.


Assuntos
Envelhecimento/patologia , Algoritmos , Mapeamento Encefálico/métodos , Encéfalo/patologia , Aprendizado de Máquina , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Neuroimage ; 206: 116329, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31689536

RESUMO

MR Fingerprinting (MRF) is a relatively new imaging framework capable of providing accurate and simultaneous quantification of multiple tissue properties for improved tissue characterization and disease diagnosis. While 2D MRF has been widely available, extending the method to 3D MRF has been an actively pursued area of research as a 3D approach can provide a higher spatial resolution and better tissue characterization with an inherently higher signal-to-noise ratio. However, 3D MRF with a high spatial resolution requires lengthy acquisition times, especially for a large volume, making it impractical for most clinical applications. In this study, a high-resolution 3D MR Fingerprinting technique, combining parallel imaging and deep learning, was developed for rapid and simultaneous quantification of T1 and T2 relaxation times. Parallel imaging was first applied along the partition-encoding direction to reduce the amount of acquired data. An advanced convolutional neural network was then integrated with the MRF framework to extract features from the MRF signal evolution for improved tissue characterization and accelerated mapping. A modified 3D-MRF sequence was also developed in the study to acquire data to train the deep learning model that can be directly applied to prospectively accelerate 3D MRF scans. Our results of quantitative T1 and T2 maps demonstrate that improved tissue characterization can be achieved using the proposed method as compared to prior methods. With the integration of parallel imaging and deep learning techniques, whole-brain (26 × 26 × 18 cm3) quantitative T1 and T2 mapping with 1-mm isotropic resolution were achieved in ~7 min. In addition, a ~7-fold improvement in processing time to extract tissue properties was also accomplished with the deep learning approach as compared to the standard template matching method. All of these improvements make high-resolution whole-brain quantitative MR imaging feasible for clinical applications.


Assuntos
Encéfalo/diagnóstico por imagem , Aprendizado Profundo , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Adulto , Feminino , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Fatores de Tempo
7.
Magn Reson Med ; 84(2): 579-591, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31854461

RESUMO

PURPOSE: To develop a rapid 2D MR fingerprinting technique with a submillimeter in-plane resolution using a deep learning-based tissue quantification approach. METHODS: A rapid and high-resolution MR fingerprinting technique was developed for brain T1 and T2 quantification. The 2D acquisition was performed using a FISP-based MR fingerprinting sequence and a spiral trajectory with 0.8-mm in-plane resolution. A deep learning-based method was used to replace the standard template matching method for improved tissue characterization. A novel network architecture (i.e., residual channel attention U-Net) was proposed to improve high-resolution details in the estimated tissue maps. Quantitative brain imaging was performed with 5 adults and 2 pediatric subjects, and the performance of the proposed approach was compared with several existing methods in the literature. RESULTS: In vivo measurements with both adult and pediatric subjects show that high-quality T1 and T2 mapping with 0.8-mm in-plane resolution can be achieved in 7.5 seconds per slice. The proposed deep learning method outperformed existing algorithms in tissue quantification with improved accuracy. Compared with the standard U-Net, high-resolution details in brain tissues were better preserved by the proposed residual channel attention U-Net. Experiments on pediatric subjects further demonstrated the potential of the proposed technique for fast pediatric neuroimaging. Alongside reduced data acquisition time, a 5-fold acceleration in tissue property mapping was also achieved with the proposed method. CONCLUSION: A rapid and high-resolution MR fingerprinting technique was developed, which enables high-quality T1 and T2 quantification with 0.8-mm in-plane resolution in 7.5 seconds per slice.


Assuntos
Aprendizado Profundo , Adulto , Algoritmos , Encéfalo/diagnóstico por imagem , Criança , Humanos , Imageamento por Ressonância Magnética , Neuroimagem
8.
J Comput Assist Tomogr ; 44(1): 43-46, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31789683

RESUMO

OBJECTIVE: The objective of this study was to investigate the frequency of hippocampal sulcus remnants (HSRs) in nonelderly adults using ultra-high-resolution 7T magnetic resonance (MR) images and their imaging features. METHODS: A total of 33 healthy adults underwent 7T MR, and multiplanar images of 66 temporal lobes were reviewed independently by 2 neuroradiologists. The detectability of the HSR was calculated. In addition, the interobserver agreement on the rating scale was evaluated using the κ statistic. RESULTS: Both observers identified HSRs with 7T MR images in all subjects. Excellent interobserver agreement was shown (κ = 1.0). The shape of HSRs was variable (spot-like, curvilinear, ovoid, or beaded appearance). Volumes of the HSRs were not correlated with age. CONCLUSIONS: Hippocampal sulcus remnants are commonly seen in healthy nonelderly adults using 7T MR imaging. Accurate diagnosis of HSR based on the microanatomy of hippocampus makes it easier to differentiate them from lesions, and it may help prevent unnecessary treatment.


Assuntos
Hipocampo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Adulto , Algoritmos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Adulto Jovem
9.
Neuroimage ; 189: 715-726, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30641240

RESUMO

Recently, resting functional MRI has provided invaluable insight into the brain developmental processes of early infancy and childhood. A common feature of previous functional development studies is the use of age to separate subjects into different cohorts for group comparisons. However, functional maturation paces vary tremendously from subject to subject. Since this is particularly true for the first years of life, an alternative to physical age alone is needed for cluster analysis. Here, a data-driven approach based on individual brain functional connectivity was employed to cluster typically developing children who were longitudinally imaged using MRI without sedation for the first two years of life. Specifically, three time periods were determined based on the distinction of brain functional connectivity patterns, including 0-1 month (group 1), 2-7 months (group 2), and 8-24 (group 3) of age, respectively. From groups 1 to 2, connection density increased by almost two-fold, local efficacy (LE) is significantly improved, and there was no change in global efficiency (GE). From groups 2 to 3, connection density increased slightly, LE showed no change, and a significant increase in GE were observed. Furthermore, 27 core brain regions were identified which yielded clustering results that resemble those obtained using all brain regions. These core regions were largely associated with the motor, visual and language functional domains as well as regions associated with higher order cognitive functional domains. Both visual and language functional domains exhibited a persistent and significant increase within domain connection from groups 1 to 3, while no changes were observed for the motor domain. In contrast, while a reduction of inter-domain connection was the general developmental pattern, the motor domain exhibited an interesting "V" shape pattern in its relationship to visual and language associated areas, showing a decrease from groups 1 to 2, followed by an increase from groups 2 to 3. In summary, our results offer new insights into functional brain development and identify 27 core brain regions critically important for early brain development.


Assuntos
Encéfalo/fisiologia , Desenvolvimento Infantil/fisiologia , Conectoma/métodos , Rede Nervosa/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Pré-Escolar , Humanos , Lactente , Imageamento por Ressonância Magnética , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/crescimento & desenvolvimento , Fatores de Tempo
10.
Genet Med ; 21(1): 224-232, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29875425

RESUMO

PURPOSE: Evaluation standards and treatment initiation timing have been debated for a long time, particularly for late-onset Fabry disease (FD), because of its slow progression. However, early initiation of enzyme replacement therapy (ERT) for FD could be effective in stabilizing the disease progression and potentially preventing irreversible organ damage. We aimed to examine globotriaosylceramide (Gb3) deposits in patients' endomyocardial biopsies to understand the early pathogenesis of FD cardiomyopathy. METHODS: Immunofluorescent (IF) staining of Gb3 and lysosomal-associated membrane protein 1 (LAMP-1) was performed on endomyocardial biopsies of patients suspected of Fabry cardiomyopathy who had negative or only slight Gb3 accumulation determined by toluidine blue staining and electron microscopic examination. RESULTS: The IF staining results revealed that all patients examined had abundant Gb3 accumulation in their cardiomyocytes, including the ones who are negative for inclusion bodies. Furthermore, we found that early Gb3 deposits were mostly confined within lysosomes, while they appeared extralysosomally at a later stage. CONCLUSION: A significant amount of lysosomal Gb3 deposits could be detected by IF staining in cardiac tissue before the formation of inclusion bodies, suggesting the cardiomyocytes might have been experiencing cellular stress and damage early on, before the appearance of typical pathological changes of FD during the disease progression.


Assuntos
Doença de Fabry/diagnóstico , Globosídeos/metabolismo , Lisossomos/metabolismo , Miocárdio/metabolismo , Triexosilceramidas/metabolismo , Adulto , Biópsia , Progressão da Doença , Terapia de Reposição de Enzimas , Doença de Fabry/diagnóstico por imagem , Doença de Fabry/metabolismo , Doença de Fabry/patologia , Imunofluorescência , Globosídeos/genética , Humanos , Proteínas de Membrana Lisossomal/genética , Lisossomos/patologia , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Triexosilceramidas/genética
11.
Epilepsia ; 60(6): 1126-1136, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31087658

RESUMO

OBJECTIVE: To investigate whether interhemispheric functional connectivity (FC) recovers in the first year after total callosotomy. METHODS: Eight epilepsy patients undergoing total callosotomy were recruited. Resting-state functional magnetic resonance imaging was acquired before and after surgery. The precallosotomy and postcallosotomy interhemispheric and intrahemispheric FC was analyzed by using graph theory and voxel-mirrored homotopic connectivity (VMHC). The seizure outcome was scored using the Engel surgical outcome scale. RESULTS: After callosotomy (mean postoperative interval = 4 months), the network density, average node degree, characteristic path length, and global efficiency of the whole interhemispheric networks were significantly decreased, compared to those in the precallosotomy networks. However, postcallosotomy interhemispheric FC and homotopic VMHC were not significantly reduced in bilateral frontal and temporal lobes. The network density and average node degree of the intrahemispheric networks were significantly increased. The characteristic path length and global efficiency of intrahemispheric networks were unchanged. SIGNIFICANCE: The interhemispheric FC may be preserved or recover early within the first postoperative year after total callosotomy, particularly in the frontal and anterior temporal lobes.


Assuntos
Corpo Caloso/diagnóstico por imagem , Corpo Caloso/cirurgia , Vias Neurais/fisiologia , Adolescente , Adulto , Idade de Início , Mapeamento Encefálico , Criança , Pré-Escolar , Epilepsia/cirurgia , Feminino , Lobo Frontal/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Recuperação de Função Fisiológica , Convulsões/cirurgia , Lobo Temporal/diagnóstico por imagem , Resultado do Tratamento , Adulto Jovem
12.
J Hum Genet ; 63(1): 1-8, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29215092

RESUMO

Many female carriers of Fabry disease are likely to develop severe morbidity and mortality. However, by our own estimation, around 80% of female newborns are missed by our current enzyme-based screening approach. Our team's aim was to develop an improved cost-effective screening method that is able to detect Fabry disease among female newborns. In Taiwan, based on a database of 916,000 newborns, ~98% of Fabry patients carry mutations out of a pool of only 21 pathogenic mutations. An Agena iPLEX platform was designed to detect these 21 pathogenic mutations using only a single-assay panel. A total of 54,791 female infants were screened and 136 female newborns with the IVS4 + 919G > A mutation and one female newborn with the c.656T > C mutation were identified. Using the current enzyme-based newborn screening approach as baseline, around 83% of female newborns are being missed. Through a family study of the IVS4 female newborns, 30 IVS4 adult family members were found to have left ventricular hypertrophy. Ten patients received endomyocardial biopsy and all were found to have significant globotriaosylceramide (Gb3) accumulation in their cardiomyocytes. All of these individuals now receive enzyme replacement therapy. We have demonstrated that the Agena iPLEX assay is a powerful tool for detecting females with Fabry disease. Furthermore, through this screening, we also have been able to identify many disease-onset adult family members who were originally undiagnosed for Fabry disease. This screening helps them to receive treatment in time before severe and irreversible cardiac damage has occurred.


Assuntos
DNA/análise , Doença de Fabry/diagnóstico , Programas de Rastreamento , Espectrometria de Massas , Adulto , Feminino , Humanos , Recém-Nascido , Programas de Rastreamento/instrumentação , Programas de Rastreamento/métodos , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Sensibilidade e Especificidade
13.
Acta Neurochir (Wien) ; 160(5): 977-986, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29397449

RESUMO

BACKGROUND: Diffusion tensor imaging (DTI) is a novel MRI technique that enables noninvasive evaluation of microstructural alterations in white matter of brain. Initially, DTI was used in intra- or inter-hemispheric association bundles. Recent technical advances are overcoming the challenges of imaging small white matter bundles, such as the cranial nerves. In this study, we use DTI to shed more light on the microstructure changes in long-standing trigeminal neuralgia. We also utilize DTI to study the effect of early stereotactic radiosurgery (SRS) on the microstructures of the trigeminal nerve and to predict the effectiveness of early SRS in the treatment of medically refractory trigeminal neuralgia (TN). METHODS: To analyze the presentation of trigeminal nerve, the DTI was reconstructed in 21 cases pre- and post-SRS. DTI parameters recorded include fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), axial diffusivity (AD), linear anisotropy coefficient (Cl), planar anisotropy coefficient (Cp), and spherical anisotropy coefficient (Cs). Comparisons between ipsilateral (symptomatic) and contralateral (asymptomatic) trigeminal nerves and symptom durations of < 5 and ≧ 5 years were performed. RESULTS: The study cohort comprised 21 patients with TN with a median age of 66 years. Initial adequate facial pain relief (Barrow Neurological Institute facial pain scores I-IIIb) was achieved in 16 (76%) patients. For the pre-SRS DTI findings, ipsilateral trigeminal nerve was associated with higher baseline root entry zone (REZ) Cs compared to contralateral nerve (0.774 vs. 0.743, p = 0.04). Ipsilateral trigeminal nerve with symptoms of < 5 years was associated with higher baseline FA compared to trigeminal nerve with symptoms of ≧ 5 years (0.314 vs. 0.244, p = 0.02). For the post-SRS DTI findings, ipsilateral trigeminal nerves with symptoms of <5 years demonstrated decrease in Cl, while those with symptoms ≧ 5 years demonstrated increase in Cl after SRS at the ipsilateral REZ (- 0.025 vs. 0.018, p = 0.04). At the cisternal segment of ipsilateral trigeminal nerve, symptoms of < 5 years were associated with decreased FA and increased λ2, while symptoms of ≧ 5 years were associated with increased FA and decreased λ2 after SRS (FA - 0.068 vs. 0.031, p = 0.04, λ2 0.0003 vs. - 0.0002, p = 0.02). CONCLUSIONS: SRS provides high rates of initial pain relief with moderate rates of facial hypoesthesia. Ipsilateral trigeminal nerve was associated with higher baseline REZ Cs, and baseline FA was associated with duration of symptoms. There were significant associations between duration of symptoms and changes in ipsilateral REZ Cl, cisternal segment FA, and cisternal segment λ2 after SRS. These preliminary findings serve as comparisons for future studies investigating the use of DTI in radiosurgical planning for patients with TN.


Assuntos
Radiocirurgia , Nervo Trigêmeo/cirurgia , Neuralgia do Trigêmeo/cirurgia , Idoso , Idoso de 80 Anos ou mais , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor , Estudos Retrospectivos , Fatores de Tempo , Neuralgia do Trigêmeo/diagnóstico por imagem
14.
BMC Neurol ; 17(1): 25, 2017 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-28166746

RESUMO

BACKGROUND: Patients with the later-onset IVS4+919G>A (IVS4) Fabry mutation are known to have positive central nervous system involvement compared with age- and sex-matched controls. This study compares central nervous system manifestations in patients with the IVS4 mutation or classical Fabry mutations. METHODS: This was a retrospective analysis of magnetic resonance imaging (MRI) data from Taiwanese patients enrolled in the Fabry Outcome Survey (sponsored by Shire; data extracted March 2015). RESULTS: Twenty-five IVS4 (19 males) and 12 (four males) classical Fabry patients underwent MRI at a median (range) age of 60.7 (45.0-70.4) and 43.0 (18.0-61.4) years, respectively. All patients received agalsidase alfa enzyme replacement therapy; two (16.7%) classical Fabry patients underwent MRI before treatment start. The pulvinar sign occurred in eight (32.0%; seven males) IVS4 and six (50.0%; three males) classical Fabry patients. Infarction occurred in eight (32.0%) IVS4 and four (33.3%) classical Fabry patients. Fazekas scores of 0, 1, 2, and 3 were found for 15 (60.0%), seven (28.0%), two (8.0%), and one (4.0%) of the IVS4 patients and for six (50.0%), four (33.3%), two (16.7%), and 0 classical Fabry patients, respectively. Abnormal height bifurcation of the basilar artery was observed in 40.0% of IVS4 and 58.3% of classical Fabry patients; abnormal laterality was observed in 4.0% of IVS4 and 16.7% of classical Fabry patients. Median (range) basilar artery diameter was 2.7 (1.4-4.0) mm in IVS4 and 3.2 (2.3-4.7) mm in classical Fabry patients (P = 0.0293); vascular stenosis was noted in 8.3% of IVS4 patients but in no classical Fabry patients. CONCLUSIONS: A similar range of MRI findings was found for both IVS4 and classical Fabry patients. Notably, basilar artery diameter was larger in classical Fabry patients than IVS4 patients.


Assuntos
Doença de Fabry/fisiopatologia , Imageamento por Ressonância Magnética/métodos , alfa-Galactosidase/genética , Adolescente , Adulto , Idade de Início , Idoso , Doença de Fabry/genética , Feminino , Humanos , Isoenzimas/genética , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Recombinantes , Estudos Retrospectivos , Taiwan , Adulto Jovem
15.
BMC Infect Dis ; 16(1): 746, 2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-27938338

RESUMO

BACKGROUND: The majority of Salmonella arizonae human infections have been reported in southwestern United States, where rattlesnake-based products are commonly used to treat illness; however, little is known in non-endemic areas. We reviewed and analyzed the clinical manifestations and treatment outcomes in adult patients with S. arizonae infection at our institution. METHOD: A retrospective study was conducted at a regional teaching hospital in southern Taiwan from July 2007 to June 2014. All adult patients diagnosed with S. arizonae infections and treated for at least three days at Chia-Yi Christian Hospital were included. Patients were followed till discharge. RESULTS: A total of 18 patients with S. arizonae infections (median age: 63.5 years) were enrolled for analysis, of whom two thirds were male. The three leading underlying diseases were diabetes mellitus, peptic ulcer disease and malignancy. Ten patients had bacteraemia and the most common infection focus was the lower respiratory tract. Most of the patients (72.2%) received third-generation cephalosporins as definitive therapy. In contrast, ampicillin-based regimens (accounting for 45.2%) were the major treatment modalities in previous reports. The crude in-hospital mortality was 5.6%, which was much lower than what was previously reported (22.7%). CONCLUSIONS: Though uncommon, there were cases of S. arizonae infections in Taiwan. Patients receiving third-generation cephalosporins treatment had better prognosis compared with those treated with ampicillin-based regimen.


Assuntos
Infecções por Salmonella/microbiologia , Salmonella arizonae/patogenicidade , Idoso , Ampicilina/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Cefalosporinas/uso terapêutico , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/mortalidade , Taiwan/epidemiologia , Resultado do Tratamento
16.
J Neuroradiol ; 43(4): 290-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27038737

RESUMO

PURPOSE: The aim of our study is to explore the impacts of different deconvolution algorithms on correlations between CBF, MTT, CBV, TTP, Tmax from MR perfusion (MRP) and angiography cerebral circulation time (CCT). METHODS: Retrospectively, 30 patients with unilateral carotid stenosis, and available pre-stenting MRP and angiography were included for analysis. All MRPs were conducted in a 1.5-T MR scanner. Standard singular value decomposition, block-circulant, and two delay-corrected algorithms were used as the deconvolution methods. All angiographies were obtained in the same bi-plane flat-detector angiographic machine. A contrast bolus of 12mL was administrated via angiocatheter at a rate of 8mL/s. The acquisition protocols were the same for all cases. CCT was defined as the difference between time to peak from the cavernous ICA and the parietal vein in lateral view. Pearson correlations were calculated for CCT and CBF, MTT, CBV, TTP, Tmax. RESULTS: The correlation between CCT and MTT was highest with Tmax (r=0.65), followed by MTT (r=0.60), CBF (r=-0.57), and TTP (r=0.33) when standard singular value decomposition was used. No correlation with CBV was noted. CONCLUSIONS: MRP using a singular value decomposition algorithm confirmed the feasibility of quantifying cerebral blood flow deficit in steno-occlusive disease within the angio-room. This approach might further improve patient safety by providing immediate cerebral hemodynamics without extraradiation and iodine contrast.


Assuntos
Algoritmos , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/patologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral/métodos , Meios de Contraste/uso terapêutico , Feminino , Humanos , Masculino , Estudos Retrospectivos
17.
Childs Nerv Syst ; 30(11): 1885-95, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25296550

RESUMO

BACKGROUND: Focal cortical dysplasia (FCD) is a specific malformation of cortical development harboring intrinsic epileptogenicity, and most of the patients develop drug-resistant epilepsy in early childhood. The detrimental effects of early and frequent seizures on cognitive function in children are significant clinical issues. In this study, we evaluate the effects of early surgical intervention of FCD on epilepsy outcome and cognitive development. METHODS: From 2006 to 2013, 30 children younger than 18 years old underwent resective surgery for FCDs at Taipei Veterans General Hospital. The mean age at surgery was 10.0 years (range 1.7 to 17.6 years). There were 21 boys and 9 girls. In this retrospective clinical study, seizure outcome, cognitive function, and quality of life were evaluated. To evaluate the effects to outcomes on early interventions, the patients were categorized into four groups according to age of seizure onset, duration of seizure before surgery, and severity of cognitive deficits. RESULTS: Eleven of 22 (50 %) patients demonstrated developmental delay preoperatively. The Engel seizure outcome achievements were class I in 21 (70 %), class II in 2 (7 %), class III in 6 (20 %), and class IV in 1 (3 %) patients. The locations of FCDs resected were in the frontal lobe in 18 cases, temporal lobe in 7, parietal lobe in 2, and in bilobes including frontoparietal lobe in 2 and parieto-occipital lobes in 1. Eight cases that had FCDs involved in the rolandic cortex presented hemiparesis before surgical resection. Motor function in four of them improved after operation. The histopathological types of FCDs were type Ia in 1, type Ib in 7, type IIa in 7, type IIb in 12, and type III in 3 patients. FCDs were completely resected in 20 patients. Eighteen (90 %) of them were seizure free (p < 0.001) with three patients that received more than one surgery to accomplish complete resection. The patients who had early seizure onset, no significant cognitive function deficit, and early surgical intervention with complete resection in less than 2 years of seizure duration showed best outcomes on seizure control, cognitive function, and quality of life. CONCLUSION: Delay in cognitive development and poor quality of life is common in children treated for FCDs. Early surgical intervention and complete resection of the lesion help for a better seizure control, cognitive function development, and quality of life. FCDs involved eloquent cortex may not prohibit complete resection for better outcomes.


Assuntos
Transtornos Cognitivos/reabilitação , Transtornos Cognitivos/cirurgia , Intervenção Educacional Precoce , Epilepsia/cirurgia , Procedimentos Neurocirúrgicos/métodos , Resultado do Tratamento , Adolescente , Criança , Pré-Escolar , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Deficiências do Desenvolvimento/cirurgia , Epilepsia/etiologia , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Malformações do Desenvolvimento Cortical/complicações , Malformações do Desenvolvimento Cortical/psicologia , Testes Neuropsicológicos , Qualidade de Vida , Estudos Retrospectivos
18.
Br J Radiol ; 97(1158): 1067-1077, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38407350

RESUMO

This review aims to serve as a foundational resource for general radiologists, enhancing their understanding of the role of Magnetic Resonance Imaging (MRI) in early prognostication for newborns diagnosed with hypoxic ischaemic encephalopathy (HIE). The article explores the application of MRI as a predictive instrument for determining long-term outcomes in newborns affected by HIE. With HIE constituting a leading cause of neonatal mortality and severe long-term neurodevelopmental impairments, early identification of prognostic indicators is crucial for timely intervention and optimal clinical management. We examine current literature and recent advancements to provide an in-depth overview of MRI predictors, encompassing brain injury patterns, injury scoring systems, spectroscopy, and diffusion imaging. The potential of these MRI biomarkers in predicting long-term neurodevelopmental outcomes and the probability of epilepsy is also discussed.


Assuntos
Hipóxia-Isquemia Encefálica , Imageamento por Ressonância Magnética , Humanos , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Recém-Nascido , Imageamento por Ressonância Magnética/métodos , Prognóstico , Encéfalo/diagnóstico por imagem
19.
Magn Reson Imaging Clin N Am ; 32(3): 395-412, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38944430

RESUMO

This review article provides a comprehensive overview of fetal MR imaging in supratentorial cerebral malformations. It emphasizes the importance of fetal MR imaging as an adjunct diagnostic tool used alongside ultrasound, improving the detection and characterization of prenatal brain abnormalities. This article reviews a spectrum of cerebral malformations, their MR imaging features, and the clinical implications of these findings. Additionally, it outlines the growing importance of fetal MR imaging in the context of perinatal care.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Diagnóstico Pré-Natal , Humanos , Gravidez , Feminino , Imageamento por Ressonância Magnética/métodos , Diagnóstico Pré-Natal/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/anormalidades , Encéfalo/embriologia
20.
Eur Radiol ; 23(9): 2612-21, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23645331

RESUMO

OBJECTIVE: To evaluate the imaging quality of head CT at lowered radiation dose by combining filtered back projection (FBP) and iterative reconstruction (IR) algorithms. METHODS: Experimental group A (n = 66) underwent CT with 43 % tube current reduction, and group B (n = 58) received an equivalent reduced dose by lowering the tube voltage. An age- and sex-matched control group (n = 72) receiving the conventional radiation dose was retrospectively collected. Imaging for the control group was reconstructed by FBP only, while images for groups A and B were reconstructed by FBP and IR. The signal-to-noise ratios (SNRs), contrast-to-noise ratios (CNRs), sharpness, number of infarcts and severity of subcortical arteriosclerotic encephalopathy (SAE) were compared to assess imaging quality and diagnostic accuracy. RESULTS: There were no significant differences in SNRs and CNRs between group A and the control group. There were significantly decreased SNRs and increased CNRs in group B. Image sharpness decreased in both groups. Correlations between detected infarcts and severity of SAE across FBP and IR were high (r = 0.73-0.93). Head diameter was the only significant factor inversely correlated with infratentorial imaging quality. CONCLUSION: Head CT with 43 % reduced tube current reconstructed by IR provides diagnostic imaging quality for outpatient management. KEY POINTS: • Cranial CT using iterative reconstruction provides diagnostic images with 43 % mAs reduction. • Blurring of infratentorial images becomes evident using low-radiation head CT. • Head diameter was inversely correlated with imaging quality in the infratentorium. • Lowering tube kilovoltage requires a higher radiation dose to maintain image quality.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Processamento de Imagem Assistida por Computador/métodos , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Algoritmos , Artefatos , Estudos de Casos e Controles , Feminino , Humanos , Modelos Lineares , Masculino , Análise Multivariada , Variações Dependentes do Observador , Pacientes Ambulatoriais , Prevalência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Espalhamento de Radiação , Razão Sinal-Ruído , Software
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