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1.
Eur Radiol ; 34(3): 1680-1691, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37658894

RESUMEN

OBJECTIVE: The potential of magnetization transfer imaging (MTI) and diffusion tensor imaging (DTI) for the detection and evolution of new multiple sclerosis (MS) lesions was analyzed. METHODS: Nineteen patients with MS obtained conventional MRI, MTI, and DTI examinations bimonthly for 12 months and again after 24 months at 1.5 T MRI. MTI was acquired with balanced steady-state free precession (bSSFP) in 10 min (1.3 mm3 isotropic resolution) yielding both magnetization transfer ratio (MTR) and quantitative magnetization transfer (qMT) parameters (pool size ratio (F), exchange rate (kf), and relaxation times (T1/T2)). DTI provided fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD). RESULTS: At the time of their appearance on MRI, the 21 newly detected MS lesions showed significantly reduced MTR/F/kf and prolonged T1/T2 parameters, as well as significantly reduced FA and increased AD/MD/RD. Significant differences were already observed for MTR 4 months and for qMT parameters 2 months prior to lesions' detection on MRI. DTI did not show any significant pre-lesional differences. Slightly reversed trends were observed for most lesions up to 8 months after their detection for qMT and less pronounced for MTR and three diffusion parameters, while appearing unchanged on MRI. CONCLUSIONS: MTI provides more information than DTI in MS lesions and detects tissue changes 2 to 4 months prior to their appearance on MRI. After lesions' detection, qMT parameter changes promise to be more sensitive than MTR for the lesions' evolutional assessment. Overall, bSSFP-based MTI adumbrates to be more sensitive than MRI and DTI for the early detection and follow-up assessment of MS lesions. CLINICAL RELEVANCE STATEMENT: When additionally acquired in routine MRI, fast bSSFP-based MTI can complement the MRI/DTI longitudinal lesion assessment by detecting MS lesions 2-4 months earlier than with MRI, which could implicate earlier clinical decisions and better follow-up/treatment assessment in MS patients. KEY POINTS: • Magnetization transfer imaging provides more information than DTI in multiple sclerosis lesions and can detect tissue changes 2 to 4 months prior to their appearance on MRI. • After lesions' detection, quantitative magnetization transfer changes are more pronounced than magnetization transfer ratio changes and therefore promise to be more sensitive for the lesions' evolutional assessment. • Balanced steady-state free precession-based magnetization transfer imaging is more sensitive than MRI and DTI for the early detection and follow-up assessment of multiple sclerosis lesions.


Asunto(s)
Imagen de Difusión Tensora , Esclerosis Múltiple , Humanos , Imagen de Difusión Tensora/métodos , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen por Resonancia Magnética/métodos , Anisotropía
2.
Ann Neurol ; 92(3): 486-502, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35713309

RESUMEN

OBJECTIVES: Neuropathological studies have shown that multiple sclerosis (MS) lesions are heterogeneous in terms of myelin/axon damage and repair as well as iron content. However, it remains a challenge to identify specific chronic lesion types, especially remyelinated lesions, in vivo in patients with MS. METHODS: We performed 3 studies: (1) a cross-sectional study in a prospective cohort of 115 patients with MS and 76 healthy controls, who underwent 3 T magnetic resonance imaging (MRI) for quantitative susceptibility mapping (QSM), myelin water fraction (MWF), and neurite density index (NDI) maps. White matter (WM) lesions in QSM were classified into 5 QSM lesion types (iso-intense, hypo-intense, hyperintense, lesions with hypo-intense rims, and lesions with paramagnetic rim legions [PRLs]); (2) a longitudinal study of 40 patients with MS to study the evolution of lesions over 2 years; (3) a postmortem histopathology-QSM validation study in 3 brains of patients with MS to assess the accuracy of QSM classification to identify neuropathological lesion types in 63 WM lesions. RESULTS: At baseline, hypo- and isointense lesions showed higher mean MWF and NDI values compared to other QSM lesion types (p < 0.0001). Further, at 2-year follow-up, hypo-/iso-intense lesions showed an increase in MWF. Postmortem analyses revealed that QSM highly accurately identifies (1) fully remyelinated areas as hypo-/iso-intense (sensitivity = 88.89% and specificity = 100%), (2) chronic inactive lesions as hyperintense (sensitivity = 71.43% and specificity = 92.00%), and (3) chronic active/smoldering lesions as PRLs (sensitivity = 92.86% and specificity = 86.36%). INTERPRETATION: These results provide the first evidence that it is possible to distinguish chronic MS lesions in a clinical setting, hereby supporting with new biomarkers to develop and assess remyelinating treatments. ANN NEUROL 2022;92:486-502.


Asunto(s)
Esclerosis Múltiple , Biomarcadores , Encéfalo/patología , Estudios Transversales , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Estudios Prospectivos , Agua
3.
J Magn Reson Imaging ; 58(3): 864-876, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36708267

RESUMEN

BACKGROUND: Detecting new and enlarged lesions in multiple sclerosis (MS) patients is needed to determine their disease activity. LeMan-PV is a software embedded in the scanner reconstruction system of one vendor, which automatically assesses new and enlarged white matter lesions (NELs) in the follow-up of MS patients; however, multicenter validation studies are lacking. PURPOSE: To assess the accuracy of LeMan-PV for the longitudinal detection NEL white-matter MS lesions in a multicenter clinical setting. STUDY TYPE: Retrospective, longitudinal. SUBJECTS: A total of 206 patients with a definitive MS diagnosis and at least two follow-up MRI studies from five centers participating in the Swiss Multiple Sclerosis Cohort study. Mean age at first follow-up = 45.2 years (range: 36.9-52.8 years); 70 males. FIELD STRENGTH/SEQUENCE: Fluid attenuated inversion recovery (FLAIR) and T1-weighted magnetization prepared rapid gradient echo (T1-MPRAGE) sequences at 1.5 T and 3 T. ASSESSMENT: The study included 313 MRI pairs of datasets. Data were analyzed with LeMan-PV and compared with a manual "reference standard" provided by a neuroradiologist. A second rater (neurologist) performed the same analysis in a subset of MRI pairs to evaluate the rating-accuracy. The Sensitivity (Se), Specificity (Sp), Accuracy (Acc), F1-score, lesion-wise False-Positive-Rate (aFPR), and other measures were used to assess LeMan-PV performance for the detection of NEL at 1.5 T and 3 T. The performance was also evaluated in the subgroup of 123 MRI pairs at 3 T. STATISTICAL TESTS: Intraclass correlation coefficient (ICC) and Cohen's kappa (CK) were used to evaluate the agreement between readers. RESULTS: The interreader agreement was high for detecting new lesions (ICC = 0.97, Pvalue < 10-20 , CK = 0.82, P value = 0) and good (ICC = 0.75, P value < 10-12 , CK = 0.68, P value = 0) for detecting enlarged lesions. Across all centers, scanner field strengths (1.5 T, 3 T), and for NEL, LeMan-PV achieved: Acc = 61%, Se = 65%, Sp = 60%, F1-score = 0.44, aFPR = 1.31. When both follow-ups were acquired at 3 T, LeMan-PV accuracy was higher (Acc = 66%, Se = 66%, Sp = 66%, F1-score = 0.28, aFPR = 3.03). DATA CONCLUSION: In this multicenter study using clinical data settings acquired at 1.5 T and 3 T, and variations in MRI protocols, LeMan-PV showed similar sensitivity in detecting NEL with respect to other recent 3 T multicentric studies based on neural networks. While LeMan-PV performance is not optimal, its main advantage is that it provides automated clinical decision support integrated into the radiological-routine flow. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Esclerosis Múltiple , Sustancia Blanca , Masculino , Humanos , Adulto , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Estudios de Cohortes , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología
4.
Brain ; 144(6): 1684-1696, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-33693571

RESUMEN

Damage to the myelin sheath and the neuroaxonal unit is a cardinal feature of multiple sclerosis; however, a detailed characterization of the interaction between myelin and axon damage in vivo remains challenging. We applied myelin water and multi-shell diffusion imaging to quantify the relative damage to myelin and axons (i) among different lesion types; (ii) in normal-appearing tissue; and (iii) across multiple sclerosis clinical subtypes and healthy controls. We also assessed the relation of focal myelin/axon damage with disability and serum neurofilament light chain as a global biological measure of neuroaxonal damage. Ninety-one multiple sclerosis patients (62 relapsing-remitting, 29 progressive) and 72 healthy controls were enrolled in the study. Differences in myelin water fraction and neurite density index were substantial when lesions were compared to healthy control subjects and normal-appearing multiple sclerosis tissue: both white matter and cortical lesions exhibited a decreased myelin water fraction and neurite density index compared with healthy (P < 0.0001) and peri-plaque white matter (P < 0.0001). Periventricular lesions showed decreased myelin water fraction and neurite density index compared with lesions in the juxtacortical region (P < 0.0001 and P < 0.05). Similarly, lesions with paramagnetic rims showed decreased myelin water fraction and neurite density index relative to lesions without a rim (P < 0.0001). Also, in 75% of white matter lesions, the reduction in neurite density index was higher than the reduction in the myelin water fraction. Besides, normal-appearing white and grey matter revealed diffuse reduction of myelin water fraction and neurite density index in multiple sclerosis compared to healthy controls (P < 0.01). Further, a more extensive reduction in myelin water fraction and neurite density index in normal-appearing cortex was observed in progressive versus relapsing-remitting participants. Neurite density index in white matter lesions correlated with disability in patients with clinical deficits (P < 0.01, beta = -10.00); and neurite density index and myelin water fraction in white matter lesions were associated to serum neurofilament light chain in the entire patient cohort (P < 0.01, beta = -3.60 and P < 0.01, beta = 0.13, respectively). These findings suggest that (i) myelin and axon pathology in multiple sclerosis is extensive in both lesions and normal-appearing tissue; (ii) particular types of lesions exhibit more damage to myelin and axons than others; (iii) progressive patients differ from relapsing-remitting patients because of more extensive axon/myelin damage in the cortex; and (iv) myelin and axon pathology in lesions is related to disability in patients with clinical deficits and global measures of neuroaxonal damage.


Asunto(s)
Axones/patología , Encéfalo/patología , Imagen de Difusión por Resonancia Magnética/métodos , Esclerosis Múltiple/patología , Vaina de Mielina/patología , Adulto , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico por imagen , Neuroimagen/métodos , Agua
5.
Mult Scler ; 26(10): 1207-1216, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31198103

RESUMEN

BACKGROUND: Teriflunomide 14 mg significantly reduced brain volume loss (BVL) and confirmed disability worsening (CDW) compared with placebo in the TEMSO core study. OBJECTIVE: To investigate the relationship between BVL from Baseline to Year 2 in the TEMSO core study and long-term CDW (Year 7) in the TEMSO long-term extension (NCT00803049). METHODS: Structural Image Evaluation using Normalization of Atrophy determined BVL. Long-term CDW was assessed by Expanded Disability Status Scale confirmed for 12 and 24 weeks. An additional analysis evaluated the relative contribution of BVL (Year 2) and other outcomes as potential mediators of the effect of teriflunomide 14 mg on 12-week CDW. RESULTS: Patients with the least BVL were significantly less likely to have 12- and 24-week CDW at Year 7 compared with patients with the most BVL. A mediation analysis revealed that BVL (Year 2) explained 51.3% of the treatment effect on CDW; new or enlarging T2w lesions over 2 years explained 30.8%, and relapses in the first 2 years explained 38.5%. CONCLUSIONS: These results highlight the potential predictive value of BVL earlier in the disease course on long-term disability outcomes. The mediation analysis suggests that teriflunomide may prevent disability worsening largely through its effects on BVL.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Encéfalo/diagnóstico por imagen , Crotonatos , Humanos , Hidroxibutiratos , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Nitrilos , Toluidinas
6.
Neuroimage ; 189: 727-733, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30685330

RESUMEN

BACKGROUND: Subcortical T2-weighted (T2w) lesions are very common in older adults and have been associated with dementia. However, little is known about the strategic lesion distribution and how lesion patterns relate to vascular risk factors and cognitive impairment. AIM: The aim of this study was to analyze the association between T2w lesion load and location, vascular risk factors, and cognitive impairment in a large cohort of older adults. METHODS: 1017 patients participating in a large prospective cohort study (INtervention project on cerebroVAscular disease and Dementia in the district of Ebersberg, INVADE II) were analyzed. Cerebral T2w white matter and deep grey matter lesions, the so-called white matter hyperintensities (WMHs), were outlined semi-automatically on fluid attenuated inversion recovery images and normalized to standard stereotaxic space (MNI152) by non-linear registration. Patients were assigned to either a low-risk or a high-risk group. The risk assessment considered ankle brachial index, intima media thickness, carotid artery stenosis, atrial fibrillation, previous cerebro-/cardiovascular events and peripheral artery disease as well as a score based on cholesterol levels, blood pressure and smoking. Separate lesion distributions were obtained for the two risk groups and compared using voxel-based lesion-symptom mapping. Moreover, we assessed the relation between lesion location and cognitive impairment (demographically adjusted z-scores of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery Plus, CERAD-NAB Plus) using voxel-based statistics (α = 0.05). RESULTS: A total of 878 out of 1017 subjects (86%) had evaluable MRI data and were included in the analyses (mean age: 68.2 ±â€¯7.6 years, female: 515). Patients in the high-risk group were characterized by a significantly higher age, a higher proportion of men, a higher lesion load (p < 0.001), and a worse performance in some of the cognitive subdomain scores (p < 0.05). Voxels with significant associations to the subjects' cerebrovascular risk profiles were mainly found at locations of the corpus callosum, superior corona radiata, superior longitudinal fasciculus, internal and external capsule, and putamen. While several cognitive domains have shown significant associations with the participants' total lesion burden (p < 0.05), no focal WMH locations were found to be associated with cognitive impairment. CONCLUSION: Age, gender, several cognitive scores, and WMH lesion load were shown to be significantly associated with vascular risk factors in a population of older, but cognitively preserved adults. Vascular risk factors seem to promote lesion formation most severely at well-defined locations. While lesion load showed weak associations to some cognitive scores, no focal locations causing specific cognitive disturbances were identified in this large cohort of older adults.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Enfermedades de los Pequeños Vasos Cerebrales/patología , Disfunción Cognitiva/etiología , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Sustancia Blanca/patología , Anciano , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/fisiopatología , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Sustancia Blanca/diagnóstico por imagen
7.
Hum Brain Mapp ; 40(14): 4091-4104, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31206931

RESUMEN

Neurodegenerative disorders, such as Alzheimer's disease (AD) and progressive forms of multiple sclerosis (MS), can affect the brainstem and are associated with atrophy that can be visualized by MRI. Anatomically accurate, large-scale assessments of brainstem atrophy are challenging due to lack of automated, accurate segmentation methods. We present a novel method for brainstem volumetry using a fully-automated segmentation approach based on multi-dimensional gated recurrent units (MD-GRU), a deep learning based semantic segmentation approach employing a convolutional adaptation of gated recurrent units. The neural network was trained on 67 3D-high resolution T1-weighted MRI scans from MS patients and healthy controls (HC) and refined using segmentations of 20 independent MS patients' scans. Reproducibility was assessed in MR test-retest experiments in 33 HC. Accuracy and robustness were examined by Dice scores comparing MD-GRU to FreeSurfer and manual brainstem segmentations in independent MS and AD datasets. The mean %-change/SD between test-retest brainstem volumes were 0.45%/0.005 (MD-GRU), 0.95%/0.009 (FreeSurfer), 0.86%/0.007 (manually edited segmentations). Comparing MD-GRU to manually edited segmentations the mean Dice scores/SD were: 0.97/0.005 (brainstem), 0.95/0.013 (mesencephalon), 0.98/0.006 (pons), 0.95/0.015 (medulla oblongata). Compared to the manual gold standard, MD-GRU brainstem segmentations were more accurate than FreeSurfer segmentations (p < .001). In the multi-centric acquired AD data, the mean Dice score/SD for the MD-GRU-manual segmentation comparison was 0.97/0.006. The fully automated brainstem segmentation method MD-GRU provides accurate, highly reproducible, and robust segmentations in HC and patients with MS and AD in 200 s/scan on an Nvidia GeForce GTX 1080 GPU and shows potential for application in large and longitudinal datasets.


Asunto(s)
Tronco Encefálico/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Esclerosis Múltiple/diagnóstico por imagen , Enfermedades Neurodegenerativas/diagnóstico por imagen , Neuroimagen/métodos , Adulto , Anciano , Aprendizaje Profundo , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
8.
J Neuroinflammation ; 15(1): 255, 2018 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-30185189

RESUMEN

BACKGROUND: We compared the magnetic resonance imaging (MRI) features between Japanese and Caucasian patients with multiple sclerosis (MS), and identified the relationships between MRI features and disability. METHODS: From the baseline data of phase II fingolimod trials, 95 Japanese and 246 Caucasian relapsing-remitting MS patients were enrolled. The number, volume, and distribution of brain MRI lesions were evaluated using T2-weighted (T2W) images. Cross-sectional total normalized brain volume (NBV), normalized cortical gray matter volume, normalized deep gray matter volume (NDGMV), normalized white matter volume (NWMV), and normalized thalamic volume were measured. RESULTS: Japanese patients had significantly lower Expanded Disability Status Scale (EDSS) scores than Caucasian patients (mean 2.0 vs. 2.3, p = 0.008), despite a similar disease duration. Japanese patients showed a trend towards fewer T2W-lesions (median 50 vs. 65, p = 0.08) and significantly lower frequencies of cerebellar and parietal lobe lesions (p = 0.02 for both) than Caucasian patients. There were no differences in T2W-lesion volume between races, whereas Japanese patients had a significantly larger T2W-lesion volume per lesion compared with Caucasian patients (median 140 mm3 vs. 85 mm3, p < 0.0001). T2W-lesion volumes were positively correlated with EDSS scores in Japanese patients (p < 0.0001). In both races, NBV, normalized cortical gray matter volume, NDGMV, and thalamic volume were negatively correlated with disease duration and EDSS scores (p < 0.01 for all). NWMV was negatively correlated with disease duration and EDSS scores only in Caucasian patients (p = 0.03 and p = 0.004, respectively). NBV, NDGMV, NWMV, and thalamic volume were consistently smaller in Japanese compared with Caucasian patients throughout the entire examined disease duration (p = 0.046, p = 0.01, p = 0.005, and p = 0.04, respectively). Japanese patients had a significantly faster reduction in NDGMV (p = 0.001), particularly for thalamic volume (p = 0.001), with disease duration compared with Caucasian patients. CONCLUSIONS: Gray matter atrophy is a common denominator for disability in Japanese and Caucasian patients. Additional contributory factors for disability include T2W-lesion volume in Japanese patients and white matter atrophy in Caucasian patients. Less frequent parietal and cerebellar involvement with fewer T2W-lesions may underlie milder disability in Japanese patients.


Asunto(s)
Encéfalo/diagnóstico por imagen , Personas con Discapacidad , Progresión de la Enfermedad , Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple , Adulto , Estudios Transversales , Evaluación de la Discapacidad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Japón , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/etnología , Esclerosis Múltiple/fisiopatología , Valores de Referencia , Índice de Severidad de la Enfermedad , Población Blanca
9.
Ann Neurol ; 82(1): 20-29, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28556498

RESUMEN

OBJECTIVE: To assess whether a high-salt diet, as measured by urinary sodium concentration, is associated with faster conversion from clinically isolated syndrome (CIS) to multiple sclerosis (MS) and MS activity and disability. METHODS: BENEFIT was a randomized clinical trial comparing early versus delayed interferon beta-1b treatment in 465 patients with a CIS. Each patient provided a median of 14 (interquartile range = 13-16) spot urine samples throughout the 5-year follow-up. We estimated 24-hour urine sodium excretion level at each time point using the Tanaka equations, and assessed whether sodium levels estimated from the cumulative average of the repeated measures were associated with clinical (conversion to MS, Expanded Disability Status Scale [EDSS]) and magnetic resonance imaging (MRI) outcomes. RESULTS: Average 24-hour urine sodium levels were not associated with conversion to clinically definite MS over the 5-year follow-up (hazard ratio [HR] = 0.91, 95% confidence interval [CI] = 0.67-1.24 per 1g increase in estimated daily sodium intake), nor were they associated with clinical or MRI outcomes (new active lesions after 6 months: HR = 1.05, 95% CI = 0.97-1.13; relative change in T2 lesion volume: -0.11, 95% CI = -0.25 to 0.04; change in EDSS: -0.01, 95% CI = -0.09 to 0.08; relapse rate: HR = 0.78, 95% CI = 0.56-1.07). Results were similar in categorical analyses using quintiles. INTERPRETATION: Our results, based on multiple assessments of urine sodium excretion over 5 years and standardized clinical and MRI follow-up, suggest that salt intake does not influence MS disease course or activity. Ann Neurol 2017;82:20-29.


Asunto(s)
Enfermedades Desmielinizantes/diagnóstico , Esclerosis Múltiple/diagnóstico , Sodio en la Dieta/efectos adversos , Adulto , Encéfalo/patología , Enfermedades Desmielinizantes/tratamiento farmacológico , Enfermedades Desmielinizantes/patología , Enfermedades Desmielinizantes/orina , Evaluación de la Discapacidad , Progresión de la Enfermedad , Femenino , Humanos , Interferon beta-1b/uso terapéutico , Imagen por Resonancia Magnética , Masculino , Neuroimagen , Sodio en la Dieta/orina , Adulto Joven
10.
Brain Topogr ; 31(5): 886-894, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29845492

RESUMEN

There is a limited correlation between white matter (WM) lesion load as determined by magnetic resonance imaging and disability in multiple sclerosis (MS). The reasons for this so-called clinico-radiological paradox are diverse and may, at least partly, relate to the fact that not just the overall lesion burden, but also the exact anatomical location of lesions predict the severity and type of disability. We aimed at studying the relationship between lesion distribution and disability using a voxel-based lesion probability mapping approach in a very large dataset of MS patients. T2-weighted lesion masks of 2348 relapsing-remitting MS patients were spatially normalized to standard stereotaxic space by non-linear registration. Relations between supratentorial WM lesion locations and disability measures were assessed using a non-parametric ANCOVA (Expanded Disability Status Scale [EDSS]; Multiple Sclerosis Functional Composite, and subscores; Modified Fatigue Impact Scale) or multinomial ordinal logistic regression (EDSS functional subscores). Data from 1907 (81%) patients were included in the analysis because of successful registration. The lesion mapping showed similar areas to be associated with the different disability scales: periventricular regions in temporal, frontal, and limbic lobes were predictive, mainly affecting the posterior thalamic radiation, the anterior, posterior, and superior parts of the corona radiata. In summary, significant associations between lesion location and clinical scores were found in periventricular areas. Such lesion clusters appear to be associated with impairment of different physical and cognitive abilities, probably because they affect commissural and long projection fibers, which are relevant WM pathways supporting many different brain functions.


Asunto(s)
Encéfalo/diagnóstico por imagen , Ensayos Clínicos como Asunto/estadística & datos numéricos , Procesamiento de Imagen Asistido por Computador/métodos , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Adolescente , Adulto , Bases de Datos Factuales , Evaluación de la Discapacidad , Fatiga/etiología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Probabilidad , Sustancia Blanca/diagnóstico por imagen , Adulto Joven
11.
Mult Scler ; 23(5): 656-664, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27411701

RESUMEN

OBJECTIVE: To define values of normalized brain volume (NBV) that can be categorized as low, medium, or high, according to baseline characteristics of relapsing-remitting multiple sclerosis (RRMS) patients. METHODS: Expected NBV (eNBV) was calculated for each patient based on age, disease duration, sex, baseline Expanded Disability Status Scale (EDSS), and T2-lesion volume, entering these variables into a multiple regression model run on 2342 RRMS patients (pooled FREEDOMS/FREEDOMS-II population). According to the difference between their observed NBV and their eNBV, patients were classified as having low NBV, medium NBV, or high NBV. We evaluated whether these NBV categories were clinically meaningful by assessing correlation with disability worsening. RESULTS: The distribution of differences between observed NBV and eNBV was used to categorize patients as having low NBV, medium NBV or high NBV. Taking the high-NBV group as reference, the hazard ratios (HRs) for 2-year disability worsening, adjusted for treatment effect, were 1.23 (95% confidence interval (CI): 0.92-1.63, p = 0.16) for the medium NBV and 1.75 (95% CI: 1.26-2.44, p = 0.001) for the low NBV. The predictive value of NBV groups was preserved over 4 years. Treatment effect appeared more evident in low-NBV patients (HR = 0.58) than in medium-NBV (HR = 0.72) and in high-NBV (HR = 0.80) patients; however, the difference was not significant ( p = 0.57). CONCLUSION: RRMS patients can be categorized into disability risk groups based on individual eNBV values according to baseline demographics and clinical characteristics.


Asunto(s)
Encéfalo/patología , Imagen por Resonancia Magnética , Esclerosis Múltiple Recurrente-Remitente/patología , Adolescente , Adulto , Atrofia/tratamiento farmacológico , Evaluación de la Discapacidad , Femenino , Humanos , Inmunosupresores/uso terapéutico , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Resultado del Tratamiento , Adulto Joven
12.
Mult Scler ; 22(10): 1297-305, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26585439

RESUMEN

BACKGROUND: 'No evidence of disease activity' (NEDA), defined as absence of magnetic resonance imaging activity (T2 and/or gadolinium-enhanced T1 lesions), relapses and disability progression ('NEDA-3'), is used as a comprehensive measure of treatment response in relapsing multiple sclerosis (RMS), but is weighted towards inflammatory activity. Accelerated brain volume loss (BVL) occurs in RMS and is an objective measure of disease worsening and progression. OBJECTIVE: To assess the contribution of individual components of NEDA-3 and the impact of adding BVL to NEDA-3 ('NEDA-4') METHODS: We analysed data pooled from two placebo-controlled phase 3 fingolimod trials in RMS and assessed NEDA-4 using different annual BVL mean rate thresholds (0.2%-1.2%). RESULTS: At 2 years, 31.0% (217/700) of patients receiving fingolimod 0.5 mg achieved NEDA-3 versus 9.9% (71/715) on placebo (odds ratio (OR) 4.07; p < 0.0001). Adding BVL (threshold of 0.4%), the respective proportions of patients achieving NEDA-4 were 19.7% (139/706) and 5.3% (38/721; OR 4.41; p < 0.0001). NEDA-4 status favoured fingolimod across all BVL thresholds tested (OR 4.01-4.41; p < 0.0001). CONCLUSION: NEDA-4 has the potential to capture the impact of therapies on both inflammation and neurodegeneration, and deserves further evaluation across different compounds and in long-term studies.


Asunto(s)
Encéfalo/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Adolescente , Adulto , Atrofia , Encéfalo/patología , Ensayos Clínicos Fase III como Asunto , Femenino , Clorhidrato de Fingolimod/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Tamaño de los Órganos , Resultado del Tratamiento , Adulto Joven
13.
BMC Neurol ; 16: 117, 2016 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-27461166

RESUMEN

BACKGROUND: Daclizumab is a humanized monoclonal antibody against CD25 that modulates interleukin 2 signaling. The SELECT TRILOGY of clinical studies (SELECT/SELECTION/SELECTED) evaluated the safety and efficacy of daclizumab in patients with relapsing-remitting multiple sclerosis (RRMS). We report the long-term safety and efficacy of daclizumab 150 mg subcutaneous every 4 weeks in patients with RRMS in the SELECTED open-label extension study. METHODS: An interim intent-to-treat analysis of all enrolled patients was performed in January 2014 for this ongoing study. RESULTS: The SELECTED study enrolled 90% of patients who completed SELECTION. In the safety and efficacy analysis (N = 410), median treatment time in SELECTED was 25 months (range, <1-45). Adverse events (AEs) were reported in 76% of patients, serious AEs (SAEs) excluding MS relapse in 16%, and treatment discontinuation due to AEs including multiple sclerosis (MS) relapse in 12%. AEs were primarily of mild to moderate severity, and common AEs (≥10%), excluding MS relapse, were nasopharyngitis (12%) and upper respiratory tract infection (12%). Most commonly reported SAEs (in ≥3 patients), excluding MS relapses, were increased serum hepatic enzymes, pneumonia, ulcerative colitis, and urinary tract infection (<1% each). Incidences of AE groups of interest include cutaneous events (28%), cutaneous SAEs (2%), gastrointestinal SAEs (2%), hepatic SAEs, (1%) and malignancies (1%). The incidence of AEs, SAEs, and treatment-related study discontinuations did not increase over time and no deaths were reported. The adjusted annualized relapse rate (95% confidence interval (CI)) analyzed at 6-month intervals was 0.15 (0.10-0.22) for weeks 97-120 and 0.15 (0.10-0.21) for weeks 121-144. In year 3, the adjusted mean (95% CI) number of new/newly enlarging T2 hyperintense lesions was 1.26 (0.93-1.72) and the mean (median) annualized change in brain volume was -0.32% (-0.34%). CONCLUSIONS: The AE incidence did not increase with extension of therapy into year 3 in SELECTED; the safety profile was similar to that previously observed. The clinical efficacy of daclizumab was sustained over the 3 years comprising the SELECT TRILOGY, although potential selection bias cannot be excluded. TRIAL REGISTRATION: Clinicaltrials.gov NCT01051349; first registered January 15, 2010.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Inmunoglobulina G/uso terapéutico , Inmunosupresores/uso terapéutico , Subunidad alfa del Receptor de Interleucina-2/uso terapéutico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Adulto , Alanina Transaminasa/efectos de los fármacos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Aspartato Aminotransferasas/efectos de los fármacos , Encéfalo/efectos de los fármacos , Estudios de Cohortes , Colitis Ulcerosa/inducido químicamente , Daclizumab , Erupciones por Medicamentos/etiología , Femenino , Estudios de Seguimiento , Humanos , Inmunoglobulina G/administración & dosificación , Inmunoglobulina G/efectos adversos , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Inyecciones Subcutáneas , Análisis de Intención de Tratar , Subunidad alfa del Receptor de Interleucina-2/administración & dosificación , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Nasofaringitis/inducido químicamente , Neumonía/inducido químicamente , Recurrencia , Infecciones del Sistema Respiratorio/inducido químicamente , Seguridad , Resultado del Tratamiento , Infecciones Urinarias/inducido químicamente
14.
Neuroimage ; 108: 87-94, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25536494

RESUMEN

Different pathological processes like demyelination and axonal loss can alter the magnetisation transfer ratio (MTR) in brain tissue. The standard method to measure this effect is to scan the respective tissue twice, one with and one without a specific saturation pulse. A major drawback of this technique based on spoiled gradient echo (GRE) sequences relates to its long acquisition time due to the saturation pulses. Recently, an alternative concept for MT imaging based on balanced steady state free precession (bSSFP) has been proposed. Modification of the duration of the radiofrequency pulses for imaging allows scanning MT sensitive and non-sensitive images. The steady-state character of bSSFP with high intrinsic signal-to-noise ratio (SNR) allows three-dimensional (3D) whole brain MTR at high spatial resolution within short and thus clinically feasible acquisition times. In the present study, both bSSFP-MT and 2D GRE-MT imaging were used in a cohort of 31 patients with multiple sclerosis (MS) to characterize different normal appearing (NA) and pathological brain structures. Under the constraint of identical SNR and scan time, a 3.4 times higher voxel size could be achieved with bSSFP. This increased resolution allowed a more accurate delineation of the different brain structures, especially of cortex, hippocampus and MS lesions. In a multiple linear regression model, we found an association between MTR of cortical lesions and a clinical measure of disability (r= -0.407, p=0.035) in the bSSFP dataset only. The different relaxation weighting of the base images (T2/T1 in bSSFP, proton density in GRE) had no effects besides a larger spreading of the MTR values of the different NA structures. This was demonstrated by the nearly perfect linearity between the NA matter MTR of both techniques as well as in the absolute MTR differences between NA matter and the respective lesions.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple Recurrente-Remitente/patología , Neuroimagen/métodos , Adulto , Anciano , Encéfalo/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
15.
Hum Brain Mapp ; 36(12): 5287-300, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26441146

RESUMEN

Heroin addiction is a severe relapsing brain disorder associated with impaired cognitive control, including deficits in attention allocation. The thalamus has a high density of opiate receptors and is critically involved in orchestrating cortical activity during cognitive control. However, there have been no studies on how acute heroin treatment modulates thalamic activity. In a cross-over, double-blind, vehicle-controlled study, 29 heroin-maintained outpatients were studied after heroin and placebo administration, while 20 healthy controls were included for the placebo condition only. Resting-state functional magnetic resonance imaging was used to analyze functional integration of the thalamus by three different resting state analysis techniques. Thalamocortical functional connectivity (FC) was analyzed by seed-based correlation, while intrinsic thalamic oscillation was assessed by analysis of regional homogeneity (ReHo) and the fractional amplitude of low frequency fluctuations (fALFF). Relative to the placebo treatment and healthy controls, acute heroin administration reduced thalamocortical FC to cortical regions, including the frontal cortex, while the reductions in FC to the mediofrontal cortex, orbitofrontal cortex, and frontal pole were positively correlated with the plasma level of morphine, the main psychoactive metabolite of heroin. Furthermore, heroin treatment was associated with increased thalamic ReHo and fALFF values, whereas fALFF following heroin exposure correlated negatively with scores of attentional control. The heroin-associated increase in fALFF was mainly dominated by slow-4 (0.027-0.073 Hz) oscillations. Our findings show that there are acute effects of heroin within the thalamocortical system and may shed new light on the role of the thalamus in cognitive control in heroin addiction. Future research is needed to determine the underlying physiological mechanisms and their role in heroin addiction.


Asunto(s)
Corteza Cerebral/patología , Dependencia de Heroína/tratamiento farmacológico , Heroína/uso terapéutico , Narcóticos/uso terapéutico , Tálamo/efectos de los fármacos , Tálamo/patología , Adulto , Corteza Cerebral/efectos de los fármacos , Estudios Cruzados , Método Doble Ciego , Imagen Eco-Planar , Femenino , Lateralidad Funcional/efectos de los fármacos , Lateralidad Funcional/fisiología , Heroína/sangre , Dependencia de Heroína/sangre , Dependencia de Heroína/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/patología , Pacientes Ambulatorios , Oxígeno/sangre , Escalas de Valoración Psiquiátrica , Estadística como Asunto , Tálamo/irrigación sanguínea , Adulto Joven
16.
Mult Scler ; 21(6): 757-66, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25480863

RESUMEN

BACKGROUND: In relapsing-remitting multiple sclerosis (RRMS), the cerebellum is a known predilection site for atrophy. Neuromyelitis optica (NMO) is characterized by extensive lesions in the spinal cord and optic nerve; however, cerebellar involvement has been less studied. Secondary degeneration of the spinocerebellar tract could impact the cerebellum in NMO. OBJECTIVE: We aimed to investigate whether spinal cord and cerebellar volume measures differ between patients with NMO and RRMS. METHODS: Volumetric analyses of the cerebellum (TCV), the upper cervical cord (UCV) as well as the whole brain (NBV) of age- and gender-matched patients with NMO (n=30; 56% AQP4 +ve) and RRMS (n=25) were performed on 3T brain magnetic resonance imaging (MRI) and compared with 34 healthy controls (HC). RESULTS: UCV was significantly reduced in NMO patients (6.3 cm(3)) as compared with HC (6.7 cm(3)), while patients with MS had reduced brain volumes compared with HC (NBV=1482 cm(3); p<0.001; TCV=188 cm(3); p=0.042), but UCV close to normal values. Patients with RRMS and NMO differed in NBV (p=0.001; lower in RRMS) and by trend (towards reduction in RRMS) in cerebellar volume (p=0.06). CONCLUSIONS: While atrophy seems to be diffuse in MS patients, a rather focussed pattern with predominant involvement of the UCV was observed in NMO patients.


Asunto(s)
Encéfalo/patología , Cerebelo/patología , Médula Cervical/patología , Esclerosis Múltiple Recurrente-Remitente/patología , Neuromielitis Óptica/patología , Adulto , Atrofia/patología , Femenino , Voluntarios Sanos , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Adulto Joven
17.
Eur Arch Psychiatry Clin Neurosci ; 265(8): 637-45, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25467383

RESUMEN

The neural mechanisms of heroin addiction are still incompletely understood, even though modern neuroimaging techniques offer insights into disease-related changes in vivo. While changes on cortical structure have been reported in heroin addiction, evidence from subcortical areas remains underrepresented. Functional imaging studies revealed that the brain reward system and particularly the nucleus accumbens (NAcc) play a pivotal role in the pathophysiology of drug addiction. The aim of this study was to investigate whether there was a volume difference of the NAcc in heroin addiction in comparison to healthy controls. A further aim was to correlate subcortical volumes with clinical measurements on negative affects in addiction. Thirty heroin-dependent patients under maintenance treatment with diacetylmorphine and twenty healthy controls underwent structural MRI scanning at 3T. Subcortical segmentation analysis was performed using FMRIB's Integrated Registration and Segmentation Tool function of FSL. The State-Trait Anxiety Inventory and the Beck Depression Inventory were used to assess trait anxiety and depressive symptoms, respectively. A decreased volume of the left NAcc was observed in heroin-dependent patients compared to healthy controls. Depression score was negatively correlated with left NAcc volume in patients, whereas a positive correlation was found between the daily opioid dose and the volume of the right amygdala. This study indicates that there might be structural differences of the NAcc in heroin-dependent patients in comparison with healthy controls. Furthermore, correlations of subcortical structures with negative emotions and opioid doses might be of future relevance for the investigation of heroin addiction.


Asunto(s)
Dependencia de Heroína/patología , Núcleo Accumbens/patología , Adulto , Análisis de Varianza , Estudios Cruzados , Femenino , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Estadística como Asunto , Suiza
18.
Lancet ; 381(9884): 2167-75, 2013 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-23562009

RESUMEN

BACKGROUND: Daclizumab, a humanised monoclonal antibody, modulates interleukin-2 signalling by blocking the α subunit (CD25) of the interleukin-2 receptor. We assessed whether daclizumab high-yield process (HYP) would be effective when given as monotherapy for a 1 year treatment period in patients with relapsing-remitting multiple sclerosis. METHODS: We did a randomised, double-blind, placebo-controlled trial at 76 centres in the Czech Republic, Germany, Hungary, India, Poland, Russia, Ukraine, Turkey, and the UK between Feb 15, 2008, and May 14, 2010. Patients aged 18-55 years with relapsing-remitting multiple sclerosis were randomly assigned (1:1:1), via a central interactive voice response system, to subcutaneous injections of daclizumab HYP 150 mg or 300 mg, or placebo, every 4 weeks for 52 weeks. Patients and study personnel were masked to treatment assignment, except for the site pharmacist who prepared the study drug for injection, but had no interaction with the patient. The primary endpoint was annualised relapse rate. Analysis was by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00390221. FINDINGS: 204 patients were assigned to receive placebo, 208 to daclizumab HYP 150 mg, and 209 to daclizumab HYP 300 mg, of whom 188 (92%), 192 (92%), and 197 (94%), respectively, completed follow-up to week 52. The annualised relapse rate was lower for patients given daclizumab HYP 150 mg (0·21, 95% CI 0·16-0·29; 54% reduction, 95% CI 33-68%; p<0·0001) or 300 mg (0·23, 0·17-0·31, 50% reduction, 28-65%; p=0·00015) than for those given placebo (0·46, 0·37-0·57). More patients were relapse free in the daclizumab HYP 150 mg (81%) and 300 mg (80%) groups than in the placebo group (64%; p<0·0001 in the 150 mg group and p=0·0003 in the 300 mg group). 12 (6%) patients in the placebo group, 15 (7%) of those in the daclizumab 150 mg group, and 19 (9%) in the 300 mg group had serious adverse events excluding multiple sclerosis relapse. One patient given daclizumab HYP 150 mg who was recovering from a serious rash died because of local complication of a psoas abscess. INTERPRETATION: Subcutaneous daclizumab HYP administered every 4 weeks led to clinically important effects on multiple sclerosis disease activity during 1 year of treatment. Our findings support the potential for daclizumab HYP to offer an additional treatment option for relapsing-remitting disease. FUNDING: Biogen Idec and AbbVie Biotherapeutics Inc.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Inmunoglobulina G/administración & dosificación , Esclerosis Múltiple Recurrente-Remitente/diagnóstico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Adolescente , Adulto , Anticuerpos Monoclonales Humanizados/efectos adversos , Daclizumab , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Europa (Continente) , Femenino , Estudios de Seguimiento , Humanos , Inmunoglobulina G/efectos adversos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Calidad de Vida , Valores de Referencia , Medición de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
19.
Hum Brain Mapp ; 35(8): 4193-203, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24510715

RESUMEN

Deep gray matter (DGM) atrophy has been reported in patients with multiple sclerosis (MS) already at early stages of the disease and progresses throughout the disease course. We studied DGM volume and shape and their relation to disability in a large cohort of clinically well-described MS patients using new subcortical segmentation methods and shape analysis. Structural 3D magnetic resonance images were acquired at 1.5 T in 118 patients with relapsing remitting MS. Subcortical structures were segmented using a multiatlas technique that relies on the generation of an automatically generated template library. To localize focal morphological changes, shape analysis was performed by estimating the vertex-wise displacements each subject must undergo to deform to a template. Multiple linear regression analysis showed that the volume of specific thalamic nuclei (the ventral nuclear complex) together with normalized gray matter volume explains a relatively large proportion of expanded disability status scale (EDSS) variability. The deformation-based displacement analysis confirmed the relation between thalamic shape and EDSS scores. Furthermore, white matter lesion volume was found to relate to the shape of all subcortical structures. This novel method for the analysis of subcortical volume and shape allows depicting specific contributions of DGM abnormalities to neurological deficits in MS patients. The results stress the importance of ventral thalamic nuclei in this respect.


Asunto(s)
Encéfalo/patología , Sustancia Gris/patología , Esclerosis Múltiple Recurrente-Remitente/patología , Adulto , Anciano , Atlas como Asunto , Estudios Transversales , Evaluación de la Discapacidad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Modelos Lineales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Retrospectivos , Núcleos Talámicos/patología , Sustancia Blanca/patología , Adulto Joven
20.
BMC Neurosci ; 15: 106, 2014 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-25200127

RESUMEN

BACKGROUND: Previous studies have demonstrated that white matter (WM) lesions bias automated brain tissue classifications and cerebral volume measurements. However, filling WM lesions using the intensity of neighbouring normal-appearing WM has been shown to increase the accuracy of automated volume measurements in the brain. In the present study, we investigate the influence of WM lesions on cortical thickness (CTh) measures and assessed the impact of lesion filling on both cross-sectional/longitudinal and global/regional measurements of CTh in multiple sclerosis (MS) patients. METHODS: Fifty MS patients were studied at baseline as well as after three and six years of follow-up. CTh was estimated using a fully automated pipeline (CIVET) on T1-weighted magnetic resonance images data acquired at 1.5 Tesla without (original) and with WM lesion filling (filled). WM lesions were semi-automatically segmented and then filled with the mean intensity of the neighbouring voxels. For both original and filled T1 images we investigated and compared the main CIVET's steps: tissue classification, surfaces generation and CTh measurement. RESULTS: On the original T1 images, the majority of WM lesion volume (72%) was wrongly classified as gray matter (GM). After lesion filling the accuracy of WM lesions classification improved significantly (p < 0.001, 94% of WM lesion volume correctly classified) as well as the WM surface generation (p < 0.0001). The mean CTh computed on the original T1 images, overall time points, was significantly thinner (p < 0.001) compared the CTh estimated on the filled T1 images. The vertex-wise longitudinal analysis performed on the filled T1 images showed an increased number of vertices in the fronto-temporal region with a significantly decrease of CTh over time compared the analysis performed on the original images. CONCLUSION: These results indicate that WM lesions bias the CTh estimation both cross-sectionally as well as longitudinally. The lesion filling approach significantly improved the accuracy of the regional CTh estimation and has an impact also on the global estimation of CTh.


Asunto(s)
Corteza Cerebral/patología , Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple/patología , Reconocimiento de Normas Patrones Automatizadas/métodos , Procesamiento de Señales Asistido por Computador , Sustancia Blanca/patología , Adulto , Estudios Transversales , Femenino , Estudios de Seguimiento , Sustancia Gris/patología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Retrospectivos , Factores de Tiempo , Adulto Joven
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