Guidelines for the use of magnetic resonance techniques in monitoring the treatment of multiple sclerosis. US National MS Society Task Force

Neurodegeneration in multiple sclerosis

Axonal loss in multiple sclerosis (MS) is a key component of disease progression and permanent neurologic disability. MS is a heterogeneous demyelinating and neurodegenerative disease of the central nervous system (CNS) with varying presentation, disease courses, and prognosis. Immunomodulatory therapies reduce the frequency and severity of inflammatory demyelinating events that are a hallmark of MS, but there is minimal therapy to treat progressive disease and there is no cure. Data from patients with MS, post-mortem histological analysis, and animal models of demyelinating disease have elucidated patterns of MS pathogenesis and underlying mechanisms of neurodegeneration. MRI and molecular biomarkers have been proposed to identify predictors of neurodegeneration and risk factors for disease progression. Early signs of axonal dysfunction have come to light including impaired mitochondrial trafficking, structural axonal changes, and synaptic alterations. With sustained inflammation as well as impaired remyelination, axons succumb to degeneration contributing to CNS atrophy and worsening of disease. These studies highlight the role of chronic demyelination in the CNS in perpetuating axonal loss, and the difficulty in promoting remyelination and repair amidst persistent inflammatory insult. Regenerative and neuroprotective strategies are essential to overcome this barrier, with early intervention being critical to rescue axonal integrity and function. The clinical and basic research studies discussed in this review have set the stage for identifying key propagators of neurodegeneration in MS, leading the way for neuroprotective therapeutic development. This article is categorized under: Immune System Diseases > Molecular and Cellular Physiology Neurological Diseases > Molecular and Cellular Physiology.

Results of a Survey on Diagnostic Procedures and Treatment Choices for Neuromyelitis Optica Spectrum Disorder in Korea: Beyond the Context of Current Clinical Guidelines

Background and Purpose

Neuromyelitis optica spectrum disorder (NMOSD) is a rare demyelinating disease of the central nervous system (CNS). We investigated the medical behaviors of experts in Korea when they are diagnosing and treating NMOSD.

Methods

An anonymous questionnaire on the diagnosis and treatment of NMOSD was distributed to experts in CNS demyelinating diseases.

Results

Most respondents used the 2015 diagnostic criteria for NMOSD and applied a cerebrospinal fluid examination, magnetic resonance imaging (MRI) of the brain and spine, and anti-aquaporin-4 antibody testing to all suspected cases of NMOSD. All respondents prescribed steroid pulse therapy as an first-line therapy in the acute phase of NMOSD, and 67% prescribed azathioprine for maintenance therapy in NMOSD. However, details regarding monitoring, the tapering period of oral steroids, second-line therapy use in refractory cases, management during pregnancy, and schedule of follow-up MRI differed according to the circumstances of individual patients. We analyzed the differences in response rates between two groups of respondents according to the annual number of NMOSD patients that they treated. The group that had been treating ≥10 NMOSD patients annually preferred rituximab more often as the second-line therapy (p=0.011) and had more experience with rituximab treatment (p=0.015) compared with the group that had been treating <10 NMOSD patients.

Conclusions

This study has revealed that NMOSD experts in Korea principally follow the available treatment guidelines. However, the differences in specific clinical practices applied to uncertain cases that have been revealed will need to be investigated further in order to formulate suitable recommendations.

MAGNIMS consensus recommendations on the use of brain and spinal cord atrophy measures in clinical practice

Early evaluation of treatment response and prediction of disease evolution are key issues in the management of people with multiple sclerosis (MS). In the past 20 years, MRI has become the most useful paraclinical tool in both situations and is used clinically to assess the inflammatory component of the disease, particularly the presence and evolution of focal lesions - the pathological hallmark of MS. However, diffuse neurodegenerative processes that are at least partly independent of inflammatory mechanisms can develop early in people with MS and are closely related to disability. The effects of these neurodegenerative processes at a macroscopic level can be quantified by estimation of brain and spinal cord atrophy with MRI. MRI measurements of atrophy in MS have also been proposed as a complementary approach to lesion assessment to facilitate the prediction of clinical outcomes and to assess treatment responses. In this Consensus statement, the Magnetic Resonance Imaging in MS (MAGNIMS) study group critically review the application of brain and spinal cord atrophy in clinical practice in the management of MS, considering the role of atrophy measures in prognosis and treatment monitoring and the barriers to clinical use of these measures. On the basis of this review, the group makes consensus statements and recommendations for future research.

FLAIR2 improves LesionTOADS automatic segmentation of multiple sclerosis lesions in non-homogenized, multi-center, 2D clinical magnetic resonance images

Background

Accurate segmentation of MS lesions on MRI is difficult and, if performed manually, time consuming. Automatic segmentations rely strongly on the image contrast and signal-to-noise ratio. Literature examining segmentation tool performances in real-world multi-site data acquisition settings is scarce.

Objective

FLAIR², a combination of T₂-weighted and fluid attenuated inversion recovery (FLAIR) images, improves tissue contrast while suppressing CSF. We compared the use of FLAIR and FLAIR² in LesionTOADS, OASIS and the lesion segmentation toolbox (LST) when applied to non-homogenized, multi-center 2D-imaging data.

Methods

Lesions were segmented on 47 MS patient data sets obtained from 34 sites using LesionTOADS, OASIS and LST, and compared to a semi-automatically generated reference. The performance of FLAIR and FLAIR² was assessed using the relative lesion volume difference (LVD), Dice coefficient (DSC), sensitivity (SEN) and symmetric surface distance (SSD). Performance improvements related to lesion volumes (LVs) were evaluated for all tools. For comparison, LesionTOADS was also used to segment lesions from 3 T single-center MR data of 40 clinically isolated syndrome (CIS) patients.

Results

Compared to FLAIR, the use of FLAIR² in LesionTOADS led to improvements of 31.6% (LVD), 14.0% (DSC), 25.1% (SEN), and 47.0% (SSD) in the multi-center study. DSC and SSD significantly improved for larger LVs, while LVD and SEN were enhanced independent of LV. OASIS showed little difference between FLAIR and FLAIR², likely due to its inherent use of T₂w and FLAIR. LST replicated the benefits of FLAIR² only in part, indicating that further optimization, particularly at low LVs is needed. In the CIS study, LesionTOADS did not benefit from the use of FLAIR² as the segmentation performance for both FLAIR and FLAIR² was heterogeneous.

Conclusions

In this real-world, multi-center experiment, FLAIR² outperformed FLAIR in its ability to segment MS lesions with LesionTOADS. The computation of FLAIR² enhanced lesion detection, at minimally increased computational time or cost, even retrospectively. Further work is needed to determine how LesionTOADS and other tools, such as LST, can optimally benefit from the improved FLAIR² contrast.

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FLAIR² improves automatic MS lesion segmentation with LesionTOADS compared to FLAIR.

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Segmentation similarity improves for higher lesion volumes, particularly for FLAIR².

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FLAIR² provides greater sensitivity independent of lesion volume than FLAIR alone.

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Other segmentation tools need further optimization to fully benefit from FLAIR².

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FLAIR² provides immediate benefits at 1.5 T and visually improves segmentation at 3 T.

Voxel-Wise Logistic Regression and Leave-One-Source-Out Cross Validation for white matter hyperintensity segmentation

Many algorithms have been proposed for automated segmentation of white matter hyperintensities (WMH) in brain MRI. Yet, broad uptake of any particular algorithm has not been observed. In this work, we argue that this may be due to variable and suboptimal validation data and frameworks, precluding direct comparison of methods on heterogeneous data. As a solution, we present Leave-One-Source-Out Cross Validation (LOSO-CV), which leverages all available data for performance estimation, and show that this gives more realistic (lower) estimates of segmentation algorithm performance on data from different scanners. We also develop a FLAIR-only WMH segmentation algorithm: Voxel-Wise Logistic Regression (VLR), inspired by the open-source Lesion Prediction Algorithm (LPA). Our variant facilitates more accurate parameter estimation, and permits intuitive interpretation of model parameters. We illustrate the performance of the VLR algorithm using the LOSO-CV framework with a dataset comprising freely available data from several recent competitions (96 images from 7 scanners). The performance of the VLR algorithm (median Similarity Index of 0.69) is compared to its LPA predecessor (0.58), and the results of the VLR algorithm in the 2017 WMH Segmentation Competition are also presented.

Safety and efficacy of helminth treatment in relapsing-remitting multiple sclerosis: Results of the HINT 2 clinical trial

BACKGROUND

The hygiene hypothesis suggests that microbial replacement may be therapeutic in allergic and autoimmune diseases. Nevertheless, the results of helminth treatment, including in multiple sclerosis (MS), have been inconclusive.

OBJECTIVE

To assess safety and brain magnetic resonance imaging (MRI) activity in subjects with relapsing-remitting multiple sclerosis (RRMS) during oral administration of ova from the porcine whipworm, Trichuris suis (TSO).

METHODS

A total of 16 disease-modifying treatment (DMT) naive RRMS subjects were studied in a baseline versus treatment (BVT) controlled prospective study. MRI scans were performed during 5 months of screening-observation, 10 months of treatment, and 4 months of post-treatment surveillance.

RESULTS

No serious symptoms or adverse events occurred during treatment. For the cohort, there was a trend consistent with a 35% diminution in active lesions when observation MRIs were compared to treatment MRIs ( p = 0.08), and at the level of individuals, 12 of 16 subjects improved during TSO treatment. T regulatory lymphocytes were increased during TSO treatment.

CONCLUSION

TSO is safe in RRMS subjects. Potentially favorable MRI outcomes and immunoregulatory changes were observed during TSO treatment; however, the magnitude of these effects was modest, and there was considerable variation among the responses of individual subjects.

The Optimization of Magnetic Resonance Imaging Pulse Sequences in Order to Better Detection of Multiple Sclerosis Plaques

BACKGROUND AND OBJECTIVE

Magnetic resonance imaging (MRI) is the most sensitive technique to detect multiple sclerosis (MS) plaques in central nervous system. In some cases, the patients who were suspected to MS, Whereas MRI images are normal, but whether patients don't have MS plaques or MRI images are not enough optimized enough in order to show MS plaques? The aim of the current study is evaluating the efficiency of different MRI sequences in order to better detection of MS plaques.

MATERIALS AND METHODS

In this cross-sectional study which was performed at Shohada-E Tajrish in Tehran - Iran hospital between October, 2011 to April, 2012, included 20 patients who suspected to MS disease were selected by the method of random sampling and underwent routine brain Pulse sequences (Axial T2w, Axial T1w, Coronal T2w, Sagittal T1w, Axial FLAIR) by Siemens, Avanto, 1.5 Tesla system. If any lesion which is suspected to the MS disease was observed, additional sequences such as: Sagittal FLAIR Fat Sat, Sagittal PDw-fat Sat, Sagittal PDw-water sat was also performed.

RESULTS

This study was performed in about 52 lesions and the results in more than 19 lesions showed that, for the Subcortical and Infratentorial areas, PDWw sequence with fat suppression is the best choice, And in nearly 33 plaques located in Periventricular area, FLAIR Fat Sat was the most effective sequence than both PDw fat and water suppression pulse sequences.

CONCLUSION

Although large plaques may visible in all images, but important problem in patients with suspected MS is screening the tiny MS plaques. This study showed that for revealing the MS plaques located in the Subcortical and Infratentorial areas, PDw-fat sat is the most effective sequence, and for MS plaques in the periventricular area, FLAIR fat Sat is the best choice.

Evidence of altered membrane phospholipid metabolism in the anterior cingulate cortex and striatum of patients with bipolar disorder I: A multi-voxel (1)H MRS study

BACKGROUND

Previous proton magnetic resonance spectroscopy ((1)H MRS) studies have reported elevated glycerophosphocholine plus phosphocholine (GPC+PC) in the basal ganglia of patients with bipolar disorders (BD), which implicates an imbalance between synthesis and degradation activity of neuronal and glia membrane phospholipids (MPLs). However, the full extent of altered metabolites of MPLs in subareas within the basal ganglia, such as caudate and putamen, as well as anterior cingulate cortex (ACC) of BD patients is poorly understood.

METHODS

Multi-voxel (1)H MRS measurements were acquired in 50 type-one BD (BD-I) and 44 healthy controls (HC) on a 3-T MRI scanner. Four different anatomically defined voxels covering ACC, caudate and putamen were systematically extracted and quantified using LCModel. Group differences in absolute GPC+PC and other metabolites were tested with age and gender as covariates.

RESULTS

BD-I patients had higher GPC+PC levels in the anterior-dorsal ACC (p = 0.037), caudate (p = 0.005) and putamen (p = 0.004) compared to HC. GPC+PC levels in the caudate were elevated most significantly in currently unmediated BD-I patients (p = 0.022) and were positively correlated with HAM-D scores (r = 0.51, p = 0.005). PCr+Cr and myo-inositol levels were also significantly higher in the caudate head (F(1,45) = 6.010, p = 0.018) of patients compared to HC. NAA and glutamate levels were not significantly different between BD-I and HC in these regions (p > 0.05).

CONCLUSION

The increased GPC+PC in BD-I patients may reflect an imbalance in the MPL metabolism. Caudate GPC+PC levels may be a potential biomarker for depressive symptoms in BD.

MRI utility in the detection of disease activity in clinically stable patients with multiple sclerosis: a retrospective analysis of a community based cohort

BACKGROUND

Since the application of MRI scanning to the diagnosis and treatment of multiple sclerosis, it has been recognized that only a small fraction of lesions seen on MRI scans produce recognizable symptoms or neurological findings. Because new lesions may occur without clinical detection, the recommendation has been made that MRI scanning be performed on a routine scheduled basis, usually yearly, even in patients who are clinically stable.

METHODS

A retrospective chart review study was conducted on MS patients who had MRI scans of the central nervous system between 2009 and 2012 at Providence Multiple Sclerosis Center. Inclusion criteria were patients with relapsing MS who had been treated with interferon beta or glatiramer acetate for 6 months or longer. Information on type, indication, and result of MRI and whether a change in disease modifying therapy occurred as a result of the scan was collected.

RESULTS

Of the 436 clinically stable patients who had routine MRI, 16.7 % of subjects had scans revealing new, enlarged or active lesions, yet in only 4.4 % patients was there a change in therapy based upon MRI results. Subjects who had MRI changes were found to be younger (50.15 vs 53.43, p = 0.02) but there was no significant difference in other demographic or clinical characteristics when compared with the subjects who did not have MRI changes. Thirty-six percent of patients with MRI changes did not change DMT due to patient request.

CONCLUSIONS

This study provides data on the likelihood of detecting MRI-documented disease activity, in patients demonstrating longer term sustained clinical stability while receiving DMTs. These results may materially assist in the decision whether or not to perform yearly MRI scanning of such patients. The potential clinical impact of the results of routine MRI scanning must be weighed against the consideration of considerable expense of frequent MRI scanning, and the yet unknown adverse impact of retained gadolinium in patients repeatedly receiving this contrast agent. The long-term clinical impact of not changing DMTs in patients in whom MRI changes were observed will be addressed in future studies of this cohort.

MRI results from the European Study on Intravenous Immunoglobulin in Secondary Progressive Multiple Sclerosis (ESIMS)

Background: Monthly application of high-dose intravenous immunoglobulin (IVIG) to patients with secondary progressive multiple sclerosis (MS) showed no clinical benefit in the European Study on Immunoglobulin in MS (ESIMS). Magnetic resonance imaging (MRI) results may provide insights into the morphologic consequences of such treatment. Methods: A total of 318 patients (mean age 44± 7 years) were enrolled in 31 European and Canadian centres and treated monthly with 1 g/kg body weight of IVIG or equivalent amounts of albumin 0.1% for 27 months. MRI was performed at baseline and after 12 and 24 months and comprised of conventional dual-echo T2-weighted and T1-weighted scans before and after application of 0.1 mmol/kg Gd-DTPA. Results: Similar to clinical variables, MRI measures at baseline were well comparable between treatment groups except for a somewhat lower mean number of contrast-enhancing lesions and number of active scans in IVIG-treated patients. Over the trial period there was almost no change of the T2-lesion load and the ‘black hole’ volume in both treatment groups and the cumulative number of contrast-enhancing lesions were similar. There was only a trend for fewer new or enlarged T2-lesions in IVIG patients, which disappeared after correction for the imbalance in the number of contrast-enhancing lesions at baseline. Brain volume in terms of a partial cerebral fraction decreased significantly less with IVIG than placebo treatment (final visit:-0.62± 0.88% versus-0.88± 0.91%; P= 0.009). This difference remained statistically significant with correction for active lesions at baseline (P= 0.02) and was seen primarily in male patients and those with an Expanded Disability Status Scale score ≥ 6 and no relapses in the two years before the study. Conclusion: The absence of significant differences in conventional MRI measures between both treatment groups parallels the negative clinical results of ESIMS. The causes for and possible long-term clinical effects of a lower rate of brain volume loss in IVIG patients should be explored further.

7T MRI-Histologic Correlation Study of Low Specific Absorption Rate T2-Weighted GRASE Sequences in the Detection of White Matter Involvement in Multiple Sclerosis

BACKGROUND

The high value of the specific absorption rate (SAR) of radio-frequency (RF) energy arising from the series of RF refocusing pulses in T2-weighted (T2-w) turbo spin echo (TSE) MRI hampers its clinical application at 7.0 Tesla (7T). T2-w gradient and spin echo (GRASE) uses the speed from gradient refocusing in combination with the chemical-shift/static magnetic field (B0) inhomogeneity insensitivity from spin-echo refocusing to acquire T2-w images with a limited number of refocusing RF pulses, thus reducing SAR.

OBJECTIVES

To investigate whether low SAR T2-w GRASE could replace T2-w TSE in detecting white matter (WM) disease in MS patients imaged at 7T.

METHODS

The .7 mm3 isotropic T2-w TSE and T2-w GRASE images with variable echo times (TEs) and echo planar imaging (EPI) factors were obtained on a 7T scanner from postmortem samples of MS brains. These samples were derived from brains of 3 female MS patients. WM lesions (WM-Ls) and normal-appearing WM (NAWM) signal intensity, WM-Ls/NAWM contrast-to-noise ratio (CNR) and MRI/myelin staining sections comparisons were obtained.

RESULTS

GRASE sequences with EPI factor/TE = 3/50 and 3/75 ms were comparable to the SE technique for measures of CNR in WM-Ls and NAWM and for detection of WM-Ls. In all sequences, however, identification of areas with remyelination, Wallerian degeneration, and gray matter demyelination, as depicted by myelin staining, was not possible.

CONCLUSIONS

T2-w GRASE images may replace T2-w TSE for clinical use. However, even at 7T, both sequences fail in detecting and characterizing MS disease beyond visible WM-Ls.

Regression to the mean and predictors of MRI disease activity in RRMS placebo cohorts--is there a place for baseline-to-treatment studies in MS?

Background

Gadolinium-enhancing (GD+) lesions and T2 lesions are MRI outcomes for phase-2 treatment trials in relapsing-remitting Multiple Sclerosis (RRMS). Little is known about predictors of lesion development and regression-to-the-mean, which is an important aspect in early baseline-to-treatment trials.

Objectives

To quantify regression-to-the-mean and identify predictors of MRI lesion development in placebo cohorts.

Methods

21 Phase-2 and Phase-3 trials were identified by a systematic literature research. Random-effects meta-analyses were performed to estimate development of T2 and GD+ after 6 months (phase-2) or 2 years (phase-3). Predictors of lesion development were evaluated with mixed-effect meta-regression.

Results

The mean number of GD+-lesions per scan was similar after 6 months (1.19, 95%CI: 0.87-1.51) and 2 years (1.19, 95%CI: 1.00-1.39). 39% of the patients were without new T2-lesion after 6 month and 19% after 2 years (95%CI: 12-25%). Mean number of baseline GD+-lesions was the best predictor for new lesions after 6 months.

Conclusion

Baseline GD-enhancing lesions predict evolution of Gd- and T2 lesions after 6 months and might be used to control for regression to the mean effects. Overall, proof-of-concept studies with a baseline to treatment design have to face a regression to 1.2 GD+lesions per scan within 6 months.

Update on the relationships between neuropsychological dysfunction and structural MRI in multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the CNS, characterized by demyelination and neurodegeneration. Besides the sensory and motor deficits that are the hallmark of this disease, approximately 50% of MS patients are cognitively impaired. Over the years, structural neuroimaging has been used widely in MS patients for both diagnostic and research purposes. Various conventional and nonconventional magnetic resonance imaging (MRI) measures have provided important information about the degree and mechanisms of cerebral pathology, and these measures correlate with cognitive and affective disturbances. In this article, recent contributions to the literature regarding the correlation between MRI and neuropsychological function in MS are reviewed.

Clinical and imaging metrics for monitoring disease progression in patients with multiple sclerosis

Multiple sclerosis (MS) is an autoimmune disease of the CNS leading to clinical disability in 250,000-350,000 young adults in the USA and Europe. The disease affects both white matter (WM) and gray matter (GM) tissues of the brain and spinal cord. While WM disease is easily quantified using currently available magnetic resonance imaging (MRI) techniques, identification and quantification of GM disease present a daily challenge. Nonconventional brain and spinal cord MRI techniques, including magnetization transfer, MRI spectroscopy and diffusion tensor imaging, have improved our understanding of MS pathology in the deep GM. The sensitivity of high-resolution MRI obtained at a high magnetic field will improve the detection of spinal cord and brain cortical GM disease. The appropriate use of the above-mentioned techniques has the potential to more accurately explain the level of disability in MS patients.

MRI outcomes in the diagnosis and disease course of multiple sclerosis

Despite major advances in MRI, including practical implementations of multiple quantitative MRI methods, the conventional measures of focal, macroscopic disease remain the core MRI outcome measures in clinical trials. MRI enhancing lesion counts are used to assess inflammation, and new T2-lesions provide an index of (interval) activity between scans. These simple MRI measures also have immediate significance for early diagnosis as components of the 2010 revised dissemination in space and time criteria, and they provide a mechanism to monitor the subclinical disease in patients, including after treatment is initiated. The focal macroscopic injury, which includes demyelination and axonal damage, is at least partially linked to the diffuse injury through pathophysiologic mechanisms, such as secondary degeneration, but the diffuse diseases is largely independent. Quantitative measures of the more widespread pathology of the normal appearing white and gray matter currently remain applicable to populations of patients rather than individuals. Gray matter pathology, including focal lesions of the cortical gray matter and diffuse changes in the deep and cortical gray has emerged as both early and clinically relevant, as has atrophy. Major technical improvements in MRI hardware and pulse sequence design allow more specific and potentially more sensitive treatment metrics required for targeting outcomes most relevant to neuronal degeneration, remyelination and repair.

Biomarkers for multiple sclerosis

Magnetic resonance imaging has been shown to be a powerful tool for diagnosing multiple sclerosis (MS) and evaluating surrogate markers of the disease activity. However, biomarkers may provide more accurate information regarding ongoing immune responses leading to demyelination and treatment effects in MS patients. Although serum biomarkers are easily accessible, they do not provide clear-cut results, whereas cerebrospinal fluid (CSF) biomarkers provide unequivocal information, although samples cannot be repeatedly obtained. For diagnosis, the presence of oligoclonal IgG bands remains important. In addition, measuring the levels of adhesion molecules, matrix metalloproteinase-9 and complement regulator factor H in the serum and evaluating the proportion of Th1/Th2 cells in the blood may be clinically feasible for monitoring the disease activity. In CSF samples, increased IL-8, IL-12, IL-17, CCL3, CCL5 and CXCL10 levels indicate active disease, and the flow cytometry findings of CSF cells can be used to detect increases in Th1 and CD4(+)CD25(+) cells during relapse. Biomarkers closely linked to the disease activity may be informative of the pathogenesis of MS, while those associated with tissue damage or repair may be targets of new treatment strategies. Establishing the latter will be a primary point of research in the near future.

Insights from magnetic resonance imaging

Recent years have witnessed impressive advancements in the use of magnetic resonance imaging (MRI) for the assessment of patients with multiple sclerosis (MS). Complementary to the clinical evaluation, conventional MRI (cMRI) provides crucial pieces of information for the diagnosis of MS, the understanding of its natural history, and monitoring the efficacy of experimental treatments. Measures derived from cMRI present clear advantages over the clinical assessment, including their more objective nature and an increased sensitivity to MS-related changes. However, the correlation between these measures and the clinical manifestations of the disease remains weak, and this can be explained, at least partially, by the limited ability of cMRI to characterize and quantify the heterogeneous features of MS pathology. Quantitative MR-based techniques have the potential to overcome the limitations of cMRI. Magnetization transfer MRI, diffusion-weighted and diffusion tensor MRI with fiber tractography, proton magnetic resonance spectroscopy, T1 and T2 relaxation time measurement, and functional MRI are contributing to elucidate the mechanisms that underlie injury, repair, and functional adaptation in patients with MS. All conventional and nonconventional MR techniques will benefit from the use of high-field MR systems (3.0T or more).

Daclizumab, an IL-2 modulating antibody for treatment of multiple sclerosis

Daclizumab is a monoclonal antibody specific for the IL-2R α chain (CD25). Daclizumab has been observed to have multiple mechanisms of action, which may contribute to beneficial effects in immune-related disease and particularly in relapsing and remitting multiple sclerosis (RRMS). These include inhibition of activated immune cells, increase of regulatory natural killer cells, effects on dendritic cells, inhibition of innate lymphoid tissue inducer cells and altered responses involving IL-2 transpresentation. The antibody has shown considerable promise in open-label and early Phase II clinical trials when used as a monotherapy, or in combination with IFN-β. In recently completed randomized trials in RRMS, treatment with daclizumab monotherapy compared with placebo resulted in clinically meaningful and statistically significant reductions in relapses, active lesions on brain MRI and slowing of disability progression. A large Phase III trial in RRMS is ongoing.

Age- and gender-related metabonomic alterations in striatum and cerebellar cortex in rats

In order to identify the neurochemical alterations in motor associated subcortical nuclei, and enhance our understanding of neurophysiology of progressive reduction in fine motor control with aging, the metabolic changes in striatum and cerebellar cortex in SD rats along with aging were investigated using a metabonomic approach based on high resolution "magic angle spinning" 1H-NMR spectroscopy and partial least squares-discriminant analysis. It was found that there were increased myo-inositol and lactate, and decreased taurine in these two brain regions of old rats. The above changes may be a marker for alterations of neuronal cells, which reduce fine motor control. Besides, some of the metabolites are gender-related and region-specific. Old female rats had decreased glutamate and increased creatine in striatum, while old male rats had increased choline in striatum, and increased GABA in cerebellar cortex, respectively. However, further analyses showed that most of the metabolites in male rats were not distinctively different with those of female ones except choline, which was in a relative lower level in striatum of male rats. All this results suggest that energy metabolism is an important indication of age-related change, which is not only in male, but also in female rats.

MRI outcomes with cladribine tablets for multiple sclerosis in the CLARITY study

We herein provide a comprehensive assessment of magnetic resonance imaging (MRI) outcomes from CLARITY, a 96-week, double-blind study demonstrating significant clinical and MRI improvements in patients with relapsing-remitting multiple sclerosis (RRMS) treated with cladribine tablets. Patients with RRMS were randomized 1:1:1 to annual short-course therapy with cladribine tablets cumulative dose 3.5 or 5.25 mg/kg or placebo. MRI endpoints included mean number of T1 gadolinium-enhancing (Gd+), active T2 and combined unique (CU) lesions/patient/scan. MRI-measured disease activity was significantly reduced in both cladribine tablets groups versus placebo. The proportion of patients with no active lesions at study end was: T1 Gd+ lesions: 86.8 and 91.0 versus 48.3 % (p < 0.001); active T2 lesions: 61.7 and 62.5 versus 28.4 % (p < 0.001); CU lesions: 59.6 and 60.7 versus 26.1 % (p < 0.001). Clinically meaningful and significant reductions in active lesion counts and increases in proportions of active lesion-free patients were achieved consistently in cladribine tablet groups when data were stratified by baseline disease characteristics. For example, the percentage of patients who remained lesion-free over the study was significantly greater in cladribine tablet groups than in the placebo group for all lesion types regardless of relapse category at baseline (p < 0.001 for all analyses of patients with ≤1 or 2 relapses; p ≤ 0.022 for analyses of patients with ≥3 relapses). MRI-measured disease activity was greatly reduced by both doses of cladribine tablets, with consistent effect across clinically relevant patient populations. These findings add to our scientific understanding of the neurological impact of this therapeutic modality in patients with RRMS.

Overall Memory Impairment Identification with Mathematical Modeling of the CVLT-II Learning Curve in Multiple Sclerosis

The CVLT-II provides standardized scores for each of the List A five learning trials, so that the clinician can compare the patient's raw trials 1-5 scores with standardized ones. However, frequently, a patient's raw scores fluctuate making a proper interpretation difficult. The CVLT-II does not offer any other methods for classifying a patient's learning and memory status on the background of the learning curve. The main objective of this research is to illustrate that discriminant analysis provides an accurate assessment of the learning curve, if suitable predictor variables are selected. Normal controls were ninety-eight healthy volunteers (78 females and 20 males). A group of MS patients included 365 patients (266 females and 99 males) with clinically defined multiple sclerosis. We show that the best predictor variables are coefficients B3 and B4 of our mathematical model B3 ∗ exp(-B2  ∗  (X - 1)) + B4  ∗  (1 - exp(-B2  ∗  (X - 1))) because discriminant functions, calculated separately for B3 and B4, allow nearly 100% correct classification. These predictors allow identification of separate impairment of readiness to learn or ability to learn, or both.

MRI-based clinical trials in relapsing-remitting MS: new sample size calculations based on a longitudinal model

BACKGROUND

Sample sizes for magnetic resonance imaging (MRI)-based clinical trials in multiple sclerosis (MS) generally assume that lesion counts are reasonably described by the negative binomial (NB) model.

OBJECTIVE

This study aimed to assess the appropriateness of the NB model for lesion count data and to provide sample sizes for placebo-controlled, MRI-based clinical trials in relapsing-remitting MS using a more realistic model.

METHODS

The fit of the NB model in each arm of five MS clinical trials was assessed using Pearson's chi-squared statistic. Required sample sizes associated with various tests of treatment effect were estimated by simulating data from a new, longitudinal model for repeated lesion count data on individual patients.

RESULTS

Evidence (p < 0.05) against the NB model was found in at least one arm of four of the five trials. If a trial is designed using this model but the resulting clinical data do not follow its assumptions then this trial can be seriously under-powered for assessing differences in mean lesion counts.

CONCLUSION

Sample sizes based on the longitudinal model are more realistic and often smaller than those previously reported using the NB model.

Intramuscular interferon beta-1a is effective in Japanese patients with relapsing-remitting multiple sclerosis: a pre-treatment versus treatment comparison study of gadolinium-enhanced MRI brain lesions

BACKGROUND AND OBJECTIVE

Interferon beta (IFNβ) is standard therapy for multiple sclerosis (MS). The efficacy of intramuscular (IM) IFNβ-1a (AVONEX(®)) was assessed in 25 Japanese patients with relapsing-remitting MS (RRMS).

METHODS

Patients with RRMS not previously treated with IFNβ or other disease-modifying therapies were included in this 36-week study. The primary outcome was the average total number of gadolinium-enhanced lesions detected on four brain MRI scans during the last 12 weeks of 24 weeks' treatment with IM IFNβ-1a 30 μg once weekly compared with the number during the 12-week pre-treatment period. Lesions were counted by blinded investigators.

RESULTS

IM IFNβ-1a significantly decreased the median number of gadolinium-enhanced lesions from 2.5 to 0.3 (p < 0.0001) compared with pre-treatment values. The median number of new gadolinium-enhanced lesions also decreased significantly from 2.0 to 0.3 (p = 0.0002). Serum neopterin was induced in a manner similar to that observed previously in a Caucasian RRMS population. No new adverse events occurred during the study.

CONCLUSION

This first study of IM IFNβ-1a in Japanese patients with RRMS demonstrated a level of efficacy similar to that reported in Caucasian patients based on an assessment of pre-treatment and post-treatment gadolinium-enhanced lesions.

Modeling MR imaging enhancing-lesion volumes in multiple sclerosis: application in clinical trials

BACKGROUND AND PURPOSE

Although the number of enhancing lesions is the typical outcome measure of choice in clinical trials in MS, a potentially more sensitive and statistically more powerful outcome measure is the volume of enhancing lesions. In this study, we assessed the distribution and statistical power of the volume of enhancing brain lesions as an outcome measure by means of their required sample size, and we compared the results with the number of enhancing lesions.

MATERIAL AND METHODS

First, a literature search was performed to compare the effects of treatment on the number and volume of enhancing lesions. Then, a statistical model was proposed to describe the distribution of the volume of enhancing lesions in 2 datasets of patients with RRMS, and sample sizes for enhancing-lesion volume as primary outcome measure were calculated.

RESULTS

A mixture of the binomial and Weibull distribution was determined to model enhancing-lesion volumes in patients. Sample size calculations for enhancing-lesion volumes showed that approximately 94 patients per arm would be required to detect a combination of 20% decrease in lesion volume and 20% increase in patients without enhancing lesions, whereas calculations for enhancing-lesion counts showed that approximately 129 patients would be required to detect a 50% decrease.

CONCLUSIONS

The mixture of the binomial and Weibull distribution is a suitable approach in modeling new enhancing-lesion volumes in MS and yielded feasible sample size estimates for clinical trials, showing lesion volumes to be an advantageous outcome measure compared with lesion counts in terms of statistical power.

Relaxation time mapping in multiple sclerosis

Several relaxation mapping techniques have been proposed to quantitatively assess disease-related brain tissue changes in multiple sclerosis. Newer developments also account for the distribution of hydrogen protons in different tissue compartments, and therefore provide markers for myelin and macromolecular content. This article will cover the broad spectrum of the pulse sequences and analysis techniques related to this topic that are currently available. Various technical and practical limitations linked with specific approaches will be discussed. These include acquisition time, accuracy and precision, radiofrequency absorption and limited coverage of the brain. Finally, the application of these techniques in the context of multiple sclerosis will be reviewed.

Probiotic helminth administration in relapsing-remitting multiple sclerosis: a phase 1 study

BACKGROUND

Probiotic treatment strategy based on the hygiene hypothesis, such as administration of ova from the non-pathogenic helminth, Trichuris suis, (TSO) has proven safe and effective in autoimmune inflammatory bowel disease.

OBJECTIVE

To study the safety and effects of TSO in a second autoimmune disease, multiple sclerosis (MS), we conducted the phase 1 Helminth-induced Immunomodulatory Therapy (HINT 1) study.

METHODS

Five subjects with newly diagnosed, treatment-naive relapsing-remitting multiple sclerosis (RRMS) were given 2500 TSO orally every 2 weeks for 3 months in a baseline versus treatment control exploratory trial.

RESULTS

The mean number of new gadolinium-enhancing magnetic resonance imaging (MRI) lesions (n-Gd+) fell from 6.6 at baseline to 2.0 at the end of TSO administration, and 2 months after TSO was discontinued, the mean number of n-Gd+ rose to 5.8. No significant adverse effects were observed. In preliminary immunological investigations, increases in the serum level of the cytokines IL-4 and IL-10 were noted in four of the five subjects.

CONCLUSION

TSO was well tolerated in the first human study of this novel probiotic in RRMS, and favorable trends were observed in exploratory MRI and immunological assessments. Further investigations will be required to fully explore the safety, effects, and mechanism of action of this immunomodulatory treatment.

Interferon regulatory factor 5 gene variants and pharmacological and clinical outcome of Interferonβ therapy in multiple sclerosis

Interferon-β (IFNβ) therapy is effective in approximately half of the patients with relapsing-remitting multiple sclerosis (RRMS). Clinical non-responders were characterized by an increased expression of IFN response genes before the start of therapy, and a lack of a pharmacologically induced increase in IFN response gene activity. Because Interferon Regulatory Factor 5 (IRF5) is a master regulator of IFN-activity, we carried out a candidate gene study of IRF5 gene variants in relation to the pharmacological and clinical response upon IFNβ treatment. We found that patients with the IRF5 rs2004640-TT and rs47281420-AA genotype exerted a poor pharmacological response to IFNβ compared with patients carrying the respective G-alleles (P=0.0006 and P=0.0023, respectively). Moreover, patients with the rs2004640-TT genotype developed more magnetic resonance imaging (MRI)-based T2 lesions during IFNβ treatment (P=0.003). Accordingly, an association between MRI-based non-responder status and rs2004640-TT genotype was observed (P=0.010). For the rs4728142-AA genotype a trend of an association with more T2 lesions during IFNβ treatment and MRI-based non-responder status was observed (P=0.103 and P=0.154, respectively). The clinical relevance of the rs2004640-TT genotype was validated in an independent cohort wherein a shorter time to first relapse was found (P=0.037). These findings suggest a role for IRF5 gene variation in the pharmacological and clinical outcome of IFNβ therapy that might have relevance as biomarker to predict the response to IFNβ in multiple sclerosis.

Retinal periphlebitis in patients with multiple sclerosis

Background/Aim. Multiple sclerosis (MS) is an immunemediated disorder of the central nervous system (CNS), characterized by inflammation, demyelination and axonal loss. Retinal periphlebitis (RP) is often present in MS patients with similar evolution and histopathological changes as MS lesions. The aim of this study was to analyze the presence of RP in MS patients during different clinical phases, and its connection with impairment of blood-brain barrier. Methods. The study included 45 patients (26 females and 19 males) with MS. Their average age was 33.2 ? 8.1 years. There were 28 patients with relapsing-remitting (RR) form, 7 with primary progresive (PP) and 10 with secondary progressive (SP) form of MS. There were 27 patients in the relapse and 18 patients in the remission phase. The average MS duration was 7.48 ? 1.3 years. Ophthalmological, neurological and MRI examination were performed in all the patients, as well as cerebrospinal fluid sampling. Albumin ratio and IgG index were calculated in all the patients. Results. There were 9 patients with RP, and 36 without it. MS duration was significantly longer in the RP group. RP was much more common in the progressive form and was not present in the remission phase of MS. Albumin ratio values were increased in the group with RP. IgG index and IgG synthesis according to Tourtellotte formula, were statistically higher in the group of patients with RP. The values of visual evoked potentials (VEP's) latency were significantly higher in the group of patients with RP. Conclusion. The presence of RP is a reliable indicator of MS activity and might be considered as a parameter for monitoring the disease activity and effects of the treatment.

Rituximab add-on therapy for breakthrough relapsing multiple sclerosis: a 52-week phase II trial

OBJECTIVE

B cells and the humoral immune system have been implicated in the pathogenesis of multiple sclerosis (MS). This study sought to evaluate the efficacy, safety, and tolerability of add-on therapy with rituximab, a monoclonal antibody that depletes circulating B cells, in subjects with relapsing MS with breakthrough disease defined by clinical and MRI activity (Class III evidence).

METHODS

Thirty subjects with a relapse within the past 18 months despite use of an injectable disease-modifying agent, and with at least 1 gadolinium-enhancing (GdE) lesion on any of 3 pretreatment MRIs, received rituximab administered at 375 mg/m(2) weekly x 4 doses. Three monthly posttreatment brain MRI scans were obtained beginning 12 weeks after the first infusion. Multiple Sclerosis Functional Composite (MSFC) and Expanded Disability Status Scale (EDSS) were obtained at baseline and throughout the posttreatment follow-up.

RESULTS

GdE lesions were reduced after treatment with rituximab, with 74% of posttreatment MRI scans being free of GdE activity compared with 26% free of GdE activity at baseline (p < 0.0001). Median GdE lesions were reduced from 1.0 to 0, and mean number was reduced from 2.81 per month to 0.33 after treatment (88% reduction). MSFC improved as well (p = 0.02). EDSS remained stable.

CONCLUSION

Rituximab add-on therapy was effective based upon blinded radiologic endpoints in this phase II study. In combination with standard injectable therapies, rituximab was well-tolerated with no serious adverse events. B-cell-modulating therapy remains a potential option for treatment of patients with relapsing MS with an inadequate response to standard injectable therapies.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that add-on rituximab reduces gadolinium-enhancing brain lesions in multiple sclerosis.

The NEO-FFI in Multiple Sclerosis: internal consistency, factorial validity, and correspondence between self and informant reports

Personality assessment is a potentially important component of clinical and empirical work with neurological patients because (a) individual differences in personality may be associated with different neurological outcomes and (b) central nervous system changes may give rise to alteration in personality. For personality assessment to be useful to clinicians and researchers, the tests must be reliable and valid, as self-report measures require certain baseline levels of comprehension and insight, both of which can be compromised by cerebral disease. In this study, the authors examined the psychometric properties of the widely used NEO Five-Factor Inventory in a group of 419 patients with multiple sclerosis. Their objective was to determine if the NEO Five-Factor Inventory is reliable and valid in this population. Results showed adequate estimates of internal consistency, factorial validity, and self-informant correlation that support its use with patients with multiple sclerosis. Implications, limitations of the current study, and directions for future research are discussed.

Improved detection of active multiple sclerosis lesions: 3D subtraction imaging

PURPOSE

To examine the benefits of using near-isotropic single-slab three-dimensional (3D) magnetic resonance (MR) imaging for the creation of subtraction images and to evaluate their performance in the detection of active multiple sclerosis (MS) brain lesions in comparison with two-dimensional (2D) subtraction images.

MATERIALS AND METHODS

The study protocol was approved by the local ethics review board and all subjects gave written informed consent before investigation. Three-dimensional MR sequences, including double inversion-recovery, fluid-attenuated inversion recovery, T2-weighted, and T1-weighted magnetization-prepared rapid acquisition gradient-echo (MP-RAGE), and corresponding 2D sequences were performed twice in 14 patients (eight women, six men; mean age, 37.6 years) with MS and nine age-matched healthy control subjects (three women, six men; mean age, 31.7 years). Active lesions were scored by two independent raters, followed by a consensus reading. Lesion counts were evaluated by using negative binomial regression; interrater agreement was evaluated by using intraclass correlation coefficient.

RESULTS

Three-dimensional subtraction images had less residual misregistration and flow artifacts and depicted higher numbers of active lesions with greater interobserver agreement compared with 2D subtraction images. Among the 3D sequences, MP-RAGE subtraction imaging enabled detection of a significantly higher mean number of positive active MS lesions compared with 2D subtraction imaging (2.8 versus 1.7, P = .012), particularly infratentorial lesions (0.6 vs 0.1, P < .05), and a substantially higher (nonsignificant) mean number of small (<3 mm) lesions (0.6 vs 0.1, P > .05).

CONCLUSION

Three-dimensional subtraction imaging, after image registration, produced better image quality, leading to increased detection of active MS lesions with greater interobserver agreement in comparison with 2D subtraction imaging; 3D MP-RAGE subtraction imaging represents a promising technique to increase sensitivity in ascertaining lesion dissemination in time and increase the power of MR imaging metrics for the evaluation of treatment effects in clinical trials.

The kynurenine pathway in adolescent depression: preliminary findings from a proton MR spectroscopy study

BACKGROUND

Cytokine induction of the enzyme indoleamine 2,3-dioxygenase (IDO) has been implicated in the development of major depressive disorder (MDD). IDO metabolizes tryptophan (TRP) into kynurenine (KYN), thereby decreasing TRP availability to the brain. KYN is further metabolized into several neurotoxins. The aims of this pilot were to examine possible relationships between plasma TRP, KYN, and 3-hydroxyanthranilic acid (3-HAA, neurotoxic metabolite) and striatal total choline (tCho, cell membrane turnover biomarker) in adolescents with MDD. We hypothesized that MDD adolescents would exhibit: i) positive correlations between KYN and 3-HAA and striatal tCho and a negative correlation between TRP and striatal tCho; and, ii) the anticipated correlations would be more pronounced in the melancholic subtype group.

METHODS

Fourteen adolescents with MDD (seven with melancholic features) and six healthy controls were enrolled. Minimums of 6 weeks MDD duration and a severity score of 40 on the Children's Depression Rating Scale-Revised were required. All were scanned at 3T with MRI, multi-voxel 3-dimensional, high, 0.75 cm(3), spatial resolution proton magnetic resonance spectroscopic imaging. Striatal tCho concentrations were assessed using phantom replacement. Spearman correlation coefficients were Bonferroni-corrected.

RESULTS

Positive correlations were found only in the melancholic group, between KYN and 3-HAA and tCho in the right caudate (r=0.93, p=0.03) and the left putamen (r=0.96, p=.006), respectively.

CONCLUSIONS

These preliminary findings suggest a possible role of the KYN pathway in adolescent melancholic MDD. Larger studies should follow.

Cerebral atrophy as outcome measure in short-term phase 2 clinical trials in multiple sclerosis

Introduction

Cerebral atrophy is a compound measure of the neurodegenerative component of multiple sclerosis (MS) and a conceivable outcome measure for clinical trials monitoring the effect of neuroprotective agents. In this study, we evaluate the rate of cerebral atrophy in a 6-month period, investigate the predictive and explanatory value of other magnetic resonance imaging (MRI) measures in relation to cerebral atrophy, and determine sample sizes for future short-term clinical trials using cerebral atrophy as primary outcome measure.

Methods

One hundred thirty-five relapsing–remitting multiple sclerosis patients underwent six monthly MRI scans from which the percentage brain volume change (PBVC) and the number and volume of gadolinium (Gd)-enhancing lesions, T2 lesions, and persistent black holes (PBH) were determined. By means of multiple linear regression analysis, the relationship between focal MRI variables and PBVC was assessed. Sample size calculations were performed for all patients and subgroups selected for enhancement or a high T2 lesion load at baseline.

Results

A significant atrophy occurred over 6 months (PBVC = −0.33%, SE = 0.061, p < 0.0001). The number of baseline T2 lesions (p = 0.024), the on-study Gd-enhancing lesion volume (p = 0.044), and the number of on-study PBHs (p = 0.003) were associated with an increased rate of atrophy. For a 50% decrease in rate of atrophy, the sample size calculations showed that approximately 283 patients per arm are required in an unselected sampled population and 185 patients per arm are required in a selected population.

Conclusion

Within a 6-month period, significant atrophy can be detected and on-study associations of PBVC and PBHs emphasizes axonal loss to be a driving mechanism. Application as primary outcome measure in short-term clinical trials with feasible sample size requires a potent drug to obtain sufficient power.

Imaging outcomes for neuroprotection and repair in multiple sclerosis trials

Multiple sclerosis (MS) is commonly regarded as an inflammatory disease, but it also has a neurodegenerative component, which represents an additional target for treatment. The use of MRI to evaluate the inflammatory disease component in 'proof-of concept' clinical trials is well established, but no systematic assessment of imaging outcomes to evaluate neuroprotection or repair in MS has been performed. In this Review, we examine the potential of traditional and novel imaging parameters to serve as primary outcomes in phase II clinical trials of neuroprotective and reparative strategies in MS. We present the conclusions of an international meeting of imaging, clinical and statistical experts, as well as a review of relevant literature. The available imaging techniques are appraised in five categories of performance: pathological specificity, reproducibility, sensitivity to change, clinical relevance, and response to treatment. At present, the three most promising primary outcomes in phase II trials of neuroprotective and/or reparative strategies in MS are: changes in whole-brain volume to gauge general cerebral atrophy; T1 hypointensity and magnetization transfer ratio to monitor the evolution of lesion damage; and optical coherence tomography findings to evaluate the anterior visual pathway. Power calculations show that these outcome measures can be applied with attainable sample sizes.

Gadolinium-enhancing or active T2 magnetic resonance imaging lesions in multiple sclerosis clinical trials?

BACKGROUND

The treatment effects in multiple sclerosis (MS) clinical trials are often estimated by monitoring disease activity by the count of "active" plaques on T2-weighted or gadolinium (Gd)-enhanced T1-weighted magnetic resonance imaging (MRI).

OBJECTIVE

To evaluate the relationship between the treatment effects estimated on T2-weighted or Gd-enhanced T1-weighted MRI.

METHODS

Data were extracted from published randomized clinical trials in relapsing-remitting MS with frequent MRI, reporting both active T2 and Gd-enhancing lesions. A regression analysis was performed between the treatment effects estimated on the two different MRI endpoints.

RESULTS

A strong association was found between the treatment effect on Gd-enhancing lesions and on active T2 lesions (R(2) = 0.93), and the treatment effect estimates were almost the same (slope = 0.96).

CONCLUSION

Defining either active T2 or Gd-enhancing lesions as MRI endpoint seems to be not crucial for monitoring MRI activity in MS clinical trials. The choice of the best MRI endpoint should be based on different considerations (e.g., sensitivity, reproducibility, time for assessment, safety, and patients' comfort). Further monitoring active T2 lesions could allow less expensive trials, without requiring injection of Gd-based contrast agents.

One-year MRI scan predicts clinical response to interferon beta in multiple sclerosis

BACKGROUND AND PURPOSE

To define the predictive value of clinical and magnetic resonance imaging (MRI) characteristics in identifying relapsing-remitting multiple sclerosis (RR-MS) patients with sustained disability progression during interferon beta (IFNB) treatment.

METHODS

All patients receiving treatment with one of the available IFNB formulations for at least 1 year were included in this single-centre, prospective and post-marketing study. Demographic, clinical and MRI data were collected at IFNB start and at 1 year of therapy; patients were followed-up at least yearly. Poor clinical response was defined as the occurrence of a sustained disability progression of > or =1 point in the Expanded Disability Status Scale (EDSS) during the follow-up period.

RESULTS

Out of 454 RR-MS patients starting IFNB therapy, data coming from 394 patients with a mean follow-up of 4.8 (2.4) years were analysed. Sixty patients were excluded because of too short follow-up. Less than 1/3 (30.4%) of the patients satisfied the criterion of 'poor responders'. Patients presenting new lesions on T2-weighted MRI scan after 1 year of therapy (compared with baseline) had a higher risk of being poor responder to treatment with IFNB during the follow-up period (HR 16.8, 95% CI 7.6-37.1, P < 0.001). An augmented risk increasing the number of lesions was observed, with a 10-fold increase for each new lesion.

CONCLUSIONS

Developing new T2-hyperintense lesions during IFNB treatment was the best predictor of long-term poor response to therapy. MRI scans performed after 1 year of IFNB treatment may be useful in contributing to early identification of poor responders.

The distribution of new enhancing lesion counts in multiple sclerosis: further explorations

Background

A statistical distribution describing the number of new enhancing lesions seen on MRI in patients with MS is of great importance for improving the statistical methodology of clinical trials using new enhancing lesions as outcome measure. We examined whether there are superior alternatives for the currently proposed negative binomial (NB) distribution.

Objective

To determine the optimal statistical distribution describing new enhancing lesion counts from a selection of six conceivable models, and to assess the effect on the distribution of a treatment effect, varying follow-up duration and selection for activity at baseline.

Methods

The statistical NB, Poisson-Inverse Gaussian (P-IG), Poisson- Lognormal (P-LN), Neyman type A (NtA), Pólya-Aeppli (PA) and Zero Inflated Poisson (ZIP) distribution were fitted on new enhancing lesion data derived from one treated and two untreated cohorts of RRMS and relapsing SPMS patients and on subgroups of varying follow-up duration and selection for baseline activity. Measure of comparison was Akaike's information criterion (AIC).

Results

Both the subgroup analyses as well as a treatment had a noticeable effect on the distributional characteristics of new enhancing lesion counts. The NB distribution generally provided the most optimal fit, closely followed by the P-IG distribution and the P-LN distribution. Fits of the PA and NtA distribution were suboptimal, while the ZIP distribution was the least adequate for modelling new enhancing lesion counts.

Conclusion

The NB distribution is the optimal distribution for modelling new enhancing lesion counts, irrespective of the effect of treatment, follow-up duration or a baseline activity selection criterion.