Acute disseminated encephalomyelitis in China, Singapore and Japan: a comparison with the USA.

BACKGROUND AND PURPOSE: Ethnicity-related differences in the incidence of acute disseminated encephalomyelitis (ADEM) and other demyelinating diseases including multiple sclerosis and neuromyelitis optica spectrum disorders have been reported. Little is reported on the influence of ethnicity and geographical location in ADEM. METHODS: Medical records of patients who presented with ADEM (ICD-9 323.61 and 323.81) at large referral hospitals in China, Singapore and Japan (years 1992-2015) were retrospectively reviewed and data were collected in a centralized database. Presenting features and outcomes of ADEM were compared between this multi-country Asian cohort and a uniformly collected US cohort using risk differences and risk ratios. Both cohorts were standardized to a 35% pediatric population to facilitate the comparison. RESULTS: There were 83 Asian patients (48 male, 16 pediatric) followed for a median of 2 (25th-75th percentile 1-10) months. Asian patients exhibited a 26% higher prevalence of spinal cord involvement on magnetic resonance imaging [95% confidence interval (CI) 0-52%; P = 0.05; 63% vs. 37%], a 39% lower prevalence of preceding events (95% CI 12-65%; P < 0.01; 33% vs. 72%) and a 23% lower prevalence of corpus callosum involvement (95% CI 7-39%; P < 0.01; 8% vs. 31%). No difference was observed between the two cohorts in the probability of relapse over the first year after disease onset. CONCLUSIONS: It is hypothesized that the high proportion of Asian patients with spinal cord lesions relates to genetic vulnerability or the higher incidence of neuromyelitis optica spectrum disorders in Asia or could be a spurious association. ADEM presentations most probably vary across geographical settings or ethnicities.

Demographic and clinical features of neuromyelitis optica: A review.

The comparative clinical and demographic features of neuromyelitis optica (NMO) are not well known. In this review we analyzed peer-reviewed publications for incidence and prevalence, clinical phenotypes, and demographic features of NMO. Population-based studies from Europe, South East and Southern Asia, the Caribbean, and Cuba suggest that the incidence and prevalence of NMO ranges from 0.05-0.4 and 0.52-4.4 per 100,000, respectively. Mean age at onset (32.6-45.7) and median time to first relapse (8-12 months) was similar. Most studies reported an excess of disease in women and a relapsing course, particularly in anti-aquaporin 4 antibody (anti AQP4-IgG)-positive patients. Ethnicity may have a bearing on disease phenotype and clinical outcome. Despite limitations inherent to the review process, themes noted in clinical and demographic features of NMO among different populations promote a more global understanding of NMO and strategies to address it.

Low testosterone is associated with disability in men with multiple sclerosis.

BACKGROUND: Gonadal steroids may modulate disease course in multiple sclerosis (MS). OBJECTIVE: To assess the prevalence and clinical associations of hypogonadism in men with MS. METHODS: Male patients, aged 18-65 years, with relapsing-remitting MS (RRMS) or clinically-isolated syndrome (CIS) and their first symptom < 10 years prior were selected from a longitudinal clinical study. We measured their hormones in stored morning blood samples, and collected their Expanded Disability Status Scale (EDSS) scores every 6 months and their Symbol Digit Modalities Test (SDMT) results annually. RESULTS: Our analysis included 96 men with a mean age of 40 years, EDSS of 1.1 and disease duration of 4.6 years. Of these men, 39% were hypogonadal (total testosterone < 288 ng/dL); none showed compensatory elevations in luteinizing hormone. Their low testosterone levels and testosterone:estradiol ratios were negatively correlated with body mass index (BMI) and leptin, and showed no correlation with 25-hydroxy-vitamin D levels. In our primary cross-sectional analyses, there was a negative age-adjusted correlation between total testosterone and EDSS (p = 0.044). In the age-adjusted longitudinal analyses, higher baseline testosterone levels were associated with less decline in SDMT (p = 0.012). CONCLUSIONS: Men with MS may experience hypogonadotropic hypogonadism. Low testosterone levels may be associated with worse clinical outcomes. A potential neuroprotective role for testosterone warrants further investigation.

Longitudinal evaluation of cognitive functioning in pediatric multiple sclerosis: report from the US Pediatric Multiple Sclerosis Network.

BACKGROUND: Approximately one-third of those with pediatric-onset multiple sclerosis (MS) experience cognitive impairment. Less is known concerning their change in cognitive functioning over time. OBJECTIVE: Changes in cognitive function over time were measured in the largest pediatric cohort to date through the US Network of Pediatric MS Centers. METHODS: A total of 67 individuals with pediatric MS (n=62) or clinically isolated syndrome (CIS, n=5), ranging from 8-17 years of age (mean age ± standard deviation (SD)=14.37 ± 2.02) completed initial and follow-up neuropsychological testing after an average of 1.64 ± 0.63 years apart. The nine tests administered measure general intellect, attention and working memory, verbal memory, visuomotor integration, language, and executive functioning. RESULTS: Rate of impairment (having one-third or more scores in the impaired range) was 37% at baseline and 33% at follow-up. Tests commonly impaired were measures of visuomotor integration, speeded processing, and attention. Most tested did not decline over two years. There was no clear pattern of change on any specific measure. CONCLUSION: Findings suggest that, over short timeframes, stable or even improved performances on measures of cognitive ability can occur. Pediatric MS may instead prevent expected age-related cognitive gains.

Sexual problems in MS: Sex differences and their impact on quality of life.

BACKGROUND: Low sexual function and satisfaction are common problems among people with multiple sclerosis (PwMS), but the literature on which patient variables are associated with these issues is inconsistent. OBJECTIVE: To investigate the associations between sexual function and satisfaction in PwMS with clinical, demographic, and patient-reported quality of life (QOL) measures and determine if sex differences exist. METHODS: This analysis includes PwMS enrolled in the Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital (CLIMB), who completed patient-reported outcome measures: Multiple Sclerosis Quality of Life-54 (MSQOL-54), Modified Fatigue Impact Scale (MFIS), and Center for Epidemiologic Studies Depression Scale (CES-D). Regression models were used to analyze associations between patient variables and function and satisfaction. Results were stratified by sex. Cross-sectional and longitudinal data were used. RESULTS: 702 PwMS (526 females,176 males, mean age 42.2 +/-11.1, median EDSS 1.5) were included in the cross-sectional analysis. Data from 341 PwMS were used in the three-year longitudinal analysis. Increasing age, disease duration, and disability were associated with reduced sexual function and satisfaction to the same degree in males and females. However, sex differences existed in the strength of associations with QOL variables. There was no significant longitudinal change in females or males. CONCLUSIONS: Age and disease duration were associated with reduced sexual function and satisfaction in males and females. In females, function was significantly associated with disability and satisfaction with fatigue. Males had stronger associations with sexual function in domains related to emotional well-being, health perceptions, and overall QOL. Males had stronger associations with satisfaction in emotional and social functioning and physical health domains. These findings can help better understand the multidimensional problems of sexual function and satisfaction in PwMS and better guide patient care.

Consensus statement: evaluation of new and existing therapeutics for pediatric multiple sclerosis.

New therapies are being evaluated by clinical trials and, if efficacious, introduced for the treatment of adult MS. The role of these new and existing agents in the management of pediatric MS has yet to be defined. Pediatric investigation plans are now required by the Food and Drug Administration and European Medicines Agency for approval of new biological agents, providing an important opportunity to gather much-needed data for clinicians caring for children and adolescents with MS. However, challenges include the small number of patients, and the need for efficient yet comprehensive study designs incorporating factors necessary to inform the clinical care of children with MS. The elected Steering committee of the International Pediatric MS Study Group (IPMSSG) conducted a structured review of existing data on the disease-modifying therapies in pediatric MS and developed a consensus statement, which was further modified by the IPMSSG general membership, using an online survey tool. Fifty-one IPMSSG members from 21 countries responded to the survey, and 50 approved the final statement. Consensus recommendations regarding use of existing first- and second-line therapies, as well as a proposed definition for inadequate treatment response, are presented. Recommendations for the use and evaluation of emerging therapies (currently in phase III clinical trials or recently approved for adult MS) are discussed. The IPMSSG endorses the inclusion of pediatric MS patients in trials evaluating appropriate new and emerging therapies. Mechanisms for conducting high-impact, multicenter studies, including long-term follow-up in pediatric MS, are required to ensure that all MS patients, irrespective of age, benefit from advances in MS therapeutics.

Predictors of hematological abnormalities in multiple sclerosis patients treated with fingolimod and dimethyl fumarate and impact of treatment switch on lymphocyte and leukocyte count.

BACKGROUND: There is limited data regarding the predictors of hematological abnormalities in multiple sclerosis (MS) patients treated with dimethyl fumarate (DMF) or fingolimod (FNG), and the impact of treatment switch on lymphocyte and leukocyte count METHODS: We identified 405 patients on DMF and 300 patients on FNG (treatment duration: at least 12 month) within a large prospective study of MS patients conducted at the Partners MS Center, Brigham and Women's Hospital (CLIMB study) between Jan 2011 to Feb 2016. Patients had complete blood counts with differentials at baseline and every 6 months while on treatment. Most participants had a clinical visit with complete neurologic examinations every 6 months and brain MRI scan every 12 months. T cell subset profile was available for subgroup of patients (n = 116). RESULTS: In the FNG group, the risk of developing lymphopenia grade 4 (< 200) was higher in female patients (p = 0.0117) and those who were previously treated with natalizumab (p = 0.0116), while the risk of lymphopenia grade 3b+4 (< 350) was higher in female patients (p = 0.0009). DMF treated patients with lower baseline lymphocyte count had a higher chance of developing lymphopenia grade 2 (< 800) (p < 0.0001) or 2+3 (< 500) (p < 0.0001). We examined the effect of treatment switch between DMF and FNG. No significant recovery in lymphocyte and leukocyte count was observed after treatment switches. Reduced dosing of FNG in patients with lymphopenia led to increase in lymphocyte count but also increased disease activity in 25% of patients. CONCLUSION: Female sex and prior exposure to natalizumab increased the probability of lymphopenia on FNG, while low absolute lymphocyte count was associated with increased risk of lymphopenia on DMF. Parallel switch did not lead to recovery from hematological abnormalities. Long-term studies with larger number of patients are required to confirm our findings and to establish guidelines for prediction and management of hematological abnormalities.

Effect of targeted disruption of STAT4 and STAT6 on the induction of experimental autoimmune encephalomyelitis.

Experimental autoimmune encephalomyelitis (EAE) is mediated by myelin-specific CD4(+) T cells secreting Th1 cytokines, while recovery from disease is associated with expression of Th2 cytokines. Investigations into the role of individual cytokines in disease induction have yielded contradictory results. Here we used animals with targeted deletion of the STAT4 or STAT6 genes to determine the role of these signaling molecules in EAE. The STAT4 pathway controls the differentiation of cells into a Th1 phenotype, while the STAT6 pathway controls the differentiation of cells into a Th2 phenotype. We found that mice deficient in STAT4 are resistant to the induction of EAE, with minimal inflammatory infiltrates in the central nervous system. In contrast, STAT6-deficient mice, which have a predominantly Th1 phenotype, experience a more severe clinical course of EAE as compared with wild-type or STAT4 knockout mice. In addition, adoptive transfer studies confirm the regulatory functions of a Th2 environment in vivo. These novel data indicate that STAT4 and STAT6 genes play a critical role in regulating the autoimmune response in EAE.

CD28-independent induction of experimental autoimmune encephalomyelitis.

Experimental autoimmune encephalomyelitis (EAE) is a T cell-mediated disease initiated by antigen-specific CD4(+) T cells. Signaling through CD28 is a critical second signal for activation of T cells, and CD28 knockout (CD28KO) mice have been reported to be resistant to induction of EAE. We now report that CD28KO mice have no intrinsic defect in mediating disease, because they developed EAE after passive transfer of primed T cells. After immunization, peripheral T cells from CD28KO mice were primed and developed memory phenotype, but had decreased antigen-specific IFN-gamma production as compared with cells from wild-type (WT) animals. Reimmunization of CD28KO mice brought out clinical disease and increased IFN-gamma production in vitro. Pathologically, there were cellular infiltrates in the central nervous system, in contrast to single-immunized mice. We show furthermore that blocking B7-1 or CTLA4, but not B7-2, in CD28KO mice induces disease after a single immunization. Thus, EAE can be induced in animals lacking CD28-dependent costimulation, suggesting that alternative costimulatory pathways were used. Blocking the OX40-OX40L costimulatory pathway differentially affected disease induction in CD28KO mice as compared with WT controls. Our data show that EAE may develop in the absence of CD28 T-cell costimulation. These findings have implications for therapies aimed at blocking costimulatory signals in autoimmune diseases.

Role of passive T-cell death in chronic experimental autoimmune encephalomyelitis.

The mechanisms of chronic disease and recovery from relapses in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis, are unknown. Deletion of myelin-specific lymphocytes by apoptosis may play a role in termination of the inflammatory response. One pathway of apoptosis is the passive cell death or "cell death by neglect" pathway, which is under the control of the Bcl family of genes. To investigate the role of passive cell death pathway in EAE, we used mice with transgenic expression of the long form of the bcl-x gene (Bcl-x(L)) targeted to the T-cell lineage. We found that mice transgenic for Bcl-x(L) have an earlier onset and a more chronic form of EAE induced by myelin oligodendrocyte glycoprotein (MOG) peptide 35-55 compared with wild-type littermate mice. This was not due to an expanded autoreactive cell repertoire. Primed peripheral lymphocytes from Bcl-x(L) transgenic mice showed increased proliferation and cytokine production to MOG peptide in vitro compared with lymphocytes from wild-type animals. Immunohistologic studies demonstrated increased cellular infiltrates, immunoglobulin precipitation, and demyelination in the Bcl-x(L) transgenic central nervous system (CNS) compared with controls. There was also a decreased number of apoptotic cells in the CNS of Bcl-x(L) transgenic mice when compared with littermates at all time points tested. This is the first report of an autoimmune disease model in Bcl-x(L) transgenic mice. Our data indicate that the passive cell death pathway is important in the pathogenesis of chronic EAE. These findings have implications for understanding the pathogenesis of multiple sclerosis and other autoimmune diseases.

Exposure to particulate matter air pollution and risk of multiple sclerosis in two large cohorts of US nurses.

BACKGROUND: Air pollution is thought to raise the risk of neurological disease by promoting neuroinflammation, oxidative stress, glial activation and cerebrovascular damage. Multiple Sclerosis is a common auto-immune disorder, primarily affecting young women. We conducted, to a large prospective study of particulate matter (PM) exposure and multiple sclerosis (MS) risk in two prospective cohorts of women: the Nurses Health Study (NHS) and the Nurses Health Study II (NHS II). METHODS: Cumulative average exposure to different size fractions of PM up to the onset of MS was estimated using spatio-temporal models. We used multivariable Cox proportional hazards models to estimate the hazard ratios (HR) and 95% confidence intervals (CI) of MS associated with each size fraction of PM independently. Participants were followed from 1998 through 2004 in NHS and from 1988 through 2007 for NHS II. We conducted additional sensitivity analyses stratified by smoking, region of the US, and age, as well as analyses restricted to women who did not move during the study. Analyses were adjusted for age, ancestry, smoking, body mass index at age 18, region, tract level population density, latitude at age 15, and UV index. RESULTS: We did not observe significant associations between air pollution and MS risk in our cohorts. Among women in the NHS II, the HRs comparing the top vs. bottom quintiles of PM was 1.11 (95% Confidence Intervals (CI): 0.74, 1.66), 1.04 (95% CI: 0.73, 1.50) and 1.09 (95% CI: 0.73, 1.62) for PM10 (≤10µm in diameter), PM2.5 (≤2.5µm in diameter), and PM2.5-10 (2.5 to 10µm in diameter) respectively, and tests for linear trends were not statistically significant. No association between exposure to PM and risk of MS was observed in the NHS. CONCLUSIONS: In this study, exposure to PM air pollution was not related to MS risk.

Evaluating the association of allergies with multiple sclerosis susceptibility risk and disease activity in a pediatric population.

BACKGROUND: Multiple sclerosis (MS) and allergies are both considered to be related to imbalanced Th1 and Th2 immune responses. Previous studies evaluating the relationship between MS and allergies provide conflicting results. OBJECTIVE: To assess allergies and asthma as risk factors for MS and as predictors of MS relapses in a pediatric cohort. METHODS: The environment and genetic risk factors for pediatric MS study is a national case-control project with 16 participating US sites. An environmental questionnaire is used that includes history of allergies in the first five years of life. Case-control data are entered in the pediatric MS Network database and cases at 12 of the 16 sites enter relapse data prospectively. Annualized relapse rate was calculated for patients with follow-up and adjusted for age at disease onset, gender, race, ethnicity, and use of disease-modifying therapy (DMT). RESULTS: We included 271 cases (mean age at disease onset of 15.7years and 62% female) and 418 controls. Relapse data were available for 193 cases. There was no difference in prevalence of allergies or asthma between cases and controls. Patients with food allergies had fewer relapses compared to patients without food allergies (0.14 vs 0.48, p=0.01). CONCLUSIONS: While allergies and asthma are not associated with pediatric MS, cases with food allergies have fewer relapses compared to those without food allergies.

Women's experiences of menopause in an online MS cohort: A case series.

BACKGROUND: Many women with multiple sclerosis (MS) are postmenopausal. Previously reported findings from an online MS cohort suggested that earlier, surgical menopause may be associated with higher patient-reported MS severity scores. OBJECTIVE: To explore experiences of menopause in a series of MS women responding to a reproductive survey from an online research platform, PatientsLikeMe (PLM). METHODS: The free-text responses from a detailed reproductive history survey deployed to PLM members were analyzed using grounded theory approach. RESULTS: Of the 208 free text responses, 127 responses related to menopause. Five themes emerged: (1) perimenopausal onset of MS symptoms, (2) overlap of MS and menopausal symptoms, (3) MS exacerbations and pseudo-exacerbations triggered by hot flashes, (4) escalation of disease course after menopause, including increasing fatigue, cognitive disturbance, and other symptoms; and (5) effect of HRT on MS symptoms. Some women reported no effects of menopause or HRT. CONCLUSION: Given an aging population and a median age of individuals currently living with MS very close to menopausal age in many cohorts, there is a pressing need to understand the impact of menopause on MS course. Qualitative responses in this study illustrated several specific themes that require quantitative testing in clinic-based cohorts.

Longitudinal BMI trajectories in multiple sclerosis: Sex differences in association with disease severity.

BACKGROUND: Adolescent obesity is a risk factor for multiple sclerosis (MS), but little is known about changes in body mass index (BMI) after MS onset. OBJECTIVE: To assess the relationship between MS and longitudinal changes in BMI. METHODS: We analyzed prospectively collected BMIs in a cohort of patients with adult-onset MS and matched adult healthy controls (HC) gathered from the same hospital network central clinical data registry. RESULTS: We made three main observations. First, at baseline MS patients had a significantly higher BMI than HC (age- and sex- adjusted mean difference=0.57; 95% CI: 0.15, 0.99; p=0.008). Second, a significant age by MS status interaction was observed (p<0.0001), such that in MS, BMIs did not increase significantly higher in older individuals, whereas BMIs in HCs were higher with increasing age. Third, we observed sex-specific associations with disease severity: higher BMI was associated with higher cross-sectional EDSS in women, but with lower EDSS in men (p=0.003, N=758). There were no longitudinal associations between BMI and EDSS in either sex or in the entire cohort (p=0.65, N=772). CONCLUSION: After MS onset, patients may not experience age-expected increases in BMI. BMI may have sex-specific associations with MS disability scores. More refined measures of body composition are warranted in future studies to distinguish adiposity from muscle mass.

Therapeutic strategies to prevent neurodegeneration and promote regeneration in multiple sclerosis.

Multiple sclerosis (MS) is an immune-mediated demyelinating and degenerative disease of the central nervous system (CNS), with lesions predominantly occurring in the CNS white matter. The current treatment for MS relies on therapies that primarily target the peripheral immune response. However, it is clear that these strategies alone are insufficient for treating the chronic progressive disability that is the ultimate outcome of the disease. Axonal degeneration may be the primary determinant of fixed neurological deficits in MS. Here, we will discuss the contribution of axonal damage to MS pathogenesis, and potential cellular and molecular targets in the prevention of neurodegeneration. In addition, we will discuss potential molecular approaches to promote repair of CNS components in multiple sclerosis.

Patients report worse MS symptoms after menopause: findings from an online cohort.

BACKGROUND: Many women with multiple sclerosis (MS) are postmenopausal, yet the impact of menopause on MS symptoms is unknown. OBJECTIVE: To investigate patient-reported impact of menopause in a large online research platform, PatientsLikeMe (PLM). METHODS: A detailed reproductive history survey was deployed to PLM members, and responses were linked to PLM׳s prospectively collected patient-reported severity score (MS Rating Scale, MSRS). The MSRS has previously shown good correlation with physician-derived EDSS scores. RESULTS: Of the 513 respondents, 55% were postmenopausal; 54% of these reported induced menopause. Median age at natural menopause was 51. Surgical menopause occurred at an earlier age (p<0.001) and was associated with more hormone replacement therapy use (p=0.02) than natural menopause. Postmenopausal status, surgical menopause, and earlier age at menopause were all associated with worse MSRS scores (p≤0.01) in regressions adjusting for age, disease type and duration. CONCLUSION: Postmenopausal patients in this study reported worse MS disease severity. Further, this study highlights a utility for online research platforms, which allow for rapid generation of hypotheses that then require validation in clinical settings.

Elevated relapse rates in pediatric compared to adult MS persist for at least 6 years.

OBJECTIVE: To compare relapse rates in pediatric-onset multiple sclerosis (POMS) and adult-onset multiple sclerosis (AOMS) over the first 6-years of disease. METHODS: Patients with relapsing-remitting disease onset were identified from the Partners Pediatric MS Center, Massachusetts General Hospital and Partners MS Center, Brigham and Women's Hospital. 84 POMS and 258 AOMS patients were included. Annualized relapse rates (ARR) for each individual year from year 1 to year 6, after first attack were compared using Poisson regression, as was expanded disability status scale (EDSS) score at the visit closest to each year interval. RESULTS: ARR was significantly higher in POMS compared to AOMS at individual years (except year 4), and was not significantly affected by adjustment for gender, race and proportion of time on treatment. Despite a 2.30 times higher relapse rate over 6-years, EDSS between groups did not differ. ARR in years 1-5 did not impact year 5 disability measured by EDSS in POMS. CONCLUSIONS: Our findings demonstrate that higher ARR in POMS relative to AOMS is sustained over 6-years, suggesting a more inflammatory nature and potential disconnect between relapses and disability measured by EDSS early in POMS. This data may be useful when designing clinical trials for POMS.

Inflammatory demyelinating diseases in children: an update.

Inflammatory demyelinating diseases (DD) affecting the central nervous system (CNS) are increasingly recognized in children. During the past decade significant advances have been made in this field. Pediatric DD are important not just because 3-5% of MS cases are diagnosed in childhood, but also because their pathogenesis may provide unique insights into the earliest events and triggers of acquired CNS DD. The purpose of this article is to offer an update into pediatric DD for the general pediatrician and child neurologist. Current evidence on epidemiology, pathology, diagnosis, management and prognosis are reviewed for both monophasic (ADEM and CIS) and polyphasic/chronic DD (MS and NMO). We also review new research advances including novel biomarkers and treatments from the latest literature.

Diffusion tensor analysis of pediatric multiple sclerosis and clinically isolated syndromes.

BACKGROUND AND PURPOSE: DTI has shown focal and diffuse white matter abnormalities in adults and children with MS. Here we explore whether DTI abnormalities are present at the time of a first attack or CIS in children and whether early DTI features can predict the development of MS. MATERIALS AND METHODS: We assessed region-of-interest and tract-based mean ADC and mean FA values for 3 major white matter pathways and NAWM in 20 children with MS, 27 children with forms of CIS, and controls. Tracts were selected by using standard region-of-interest placements on color FA maps. Identical ROIs were placed in the NAWM on b = 0 T2-weighted images to ensure that both ROIs and resulting tracts passed through NAWM. Conventional MR imaging characteristics were assessed by visual inspection. Statistical analysis compared FA and ADC values between groups by a t test. Logistic regression assessed the predictive value of DTI measures and published conventional MR imaging measures for conversion from CIS to MS. RESULTS: In pediatric patients with MS, all white matter pathways and analysis confined to the NAWM demonstrated higher mean ADC values and lower mean FA than in controls. In contrast, there were no significant differences in mean ADC and mean FA of white matter pathways in all CIS cohorts compared with controls. In the CIS cohort, none of the DTI measures in white matter pathways or in NAWM were significantly associated with conversion to RRMS in univariate or multivariate models (P > .05 in all models). CONCLUSIONS: There are significant anisotropic abnormalities in the NAWM of major tracts in children with MS. In contrast, there were no significant changes in pediatric patients with CIS compared with controls at baseline. DTI measures did not predict conversion to MS. The period between CIS and conversion to pediatric MS may represent a window of opportunity for the prevention of diffuse damage in the CNS and potentially progressive disability.

The impact of lesion in-painting and registration methods on voxel-based morphometry in detecting regional cerebral gray matter atrophy in multiple sclerosis.

BACKGROUND AND PURPOSE: VBM has been widely used to study GM atrophy in MS. MS lesions lead to segmentation and registration errors that may affect the reliability of VBM results. Improved segmentation and registration have been demonstrated by WM LI before segmentation. DARTEL appears to improve registration versus the USM. Our aim was to compare the performance of VBM-DARTEL versus VBM-USM and the effect of LI in the regional analysis of GM atrophy in MS. MATERIALS AND METHODS: 3T T1 MR imaging scans were acquired from 26 patients with RRMS and 28 age-matched NC. LI replaced WM lesions with normal-appearing WM intensities before image segmentation. VBM analysis was performed in SPM8 by using DARTEL and USM with and without LI, allowing the comparison of 4 VBM methods (DARTEL + LI, DARTEL - LI, USM + LI, and USM - LI). Accuracy of VBM was assessed by using NMI, CC, and a simulation analysis. RESULTS: Overall, DARTEL + LI yielded the most accurate GM maps among the 4 methods (highest NMI and CC, P < .001). DARTEL + LI showed significant GM loss in the bilateral thalami and caudate nuclei in patients with RRMS versus NC. The other 3 methods overestimated the number of regions of GM loss in RRMS versus NC. LI improved the accuracy of both VBM methods. Simulated data suggested the accuracy of the results provided from patient MR imaging analysis. CONCLUSIONS: We introduce a pipeline that shows promise in limiting segmentation and registration errors in VBM analysis in MS.