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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.

Magnetization transfer ratio (MTR) is a sensitive parameter to quantify the integrity of myelinated white matter in patients with multiple sclerosis. Lesional MTR decreases in the acute phase due to demyelination, and subsequently shows recovery depending on the degree of remyelination in the absence of axonal loss. Recovery of average lesion MTR therefore might prove a viable outcome measure to assess the effect of remyelinating agents. Our objective was to determine the required sample size for phase II multicentre clinical trials using the recovery of average lesion MTR as primary outcome measure. With 7-monthly MRI scans, the MTR evolution of 349 new enhancing lesions before and after enhancement was assessed in 32 MS patients from 5 centres. Multilevel models were fitted to the data yielding estimates for the variance components, which were applied in power calculations. Sample sizes were determined for placebo-controlled, multicentre trials using lesional MTR recovery post-enhancement as primary outcome measure. Average lesion MTR decreased slightly in the build-up to enhancement, decreased dramatically during enhancement and showed recovery in the period after cessation. The power calculations showed that for a power of 80%, approximately 136 patients per trial (mean number of 6 lesions per patient) are required to detect a 30% increase in lesional MTR post-enhancement compared with placebo, whereas 48 subjects are required to detect a 50% increase in lesional MTR compared with placebo. Recovery of lesion MTR is a feasible outcome measure for future multicentre clinical trials measuring the effect of remyelinating agents.

Background: Several studies have confirmed the predictive value of baseline and follow-up magnetic resonance (MR) imaging variables for conversion to clinically definite multiple sclerosis (CDMS), depending on the population, follow-up duration, and treatment intervention. However, the timing of follow-up imaging and the effect of treatment intervention on the predictive value of baseline MR imaging variables require further elucidation., Objectives: To assess the prognostic value of baseline MR imaging variables for conversion to CDMS over 3 years and whether this was affected by treatment intervention and (2) to assess the increased risk for conversion posed by dissemination in time on follow-up MR imaging., Design: Cohort study., Setting: Multicenter randomized clinical trial., Patients: Four hundred sixty-eight patients with a clinically isolated syndrome who had an initial clinical demyelinating event within the past 60 days who received early treatment (3 years of interferon beta-1b) or delayed treatment (placebo first, followed by > or =1 year of interferon beta-1b). Intervention Magnetic resonance imaging. Main Outcome Measure Time to CDMS., Results: The overall conversion rate to CDMS was 42%. Barkhof criteria with the strongest prognostic value were the presence at baseline of at least 9 T2-weighted lesions (hazard ratio [HR], 1.64; 95% confidence interval [CI], 1.15-2.33; P = .006) and at least 3 periventricular lesions (1.66; 1.14-2.41; P = .009). No specific advantage was noted in using a fixed cutoff of at least 3 Barkhof criteria (HR, 1.31; 95% CI, 0.95-1.79; P = .10). The prognostic value of all MR imaging criteria was unaffected by treatment intervention (P > or = .20 for all). Dissemination in time resulted in increased risk for CDMS only in patients without dissemination in space at baseline and was most informative at the 9-month MR imaging (HR, 2.72; 95% CI, 1.26-5.87; P = .01)., Conclusions: The modified Barkhof criteria showed moderate predictive value for conversion to CDMS, although all patients had received interferon beta-1b therapy for at least 1 year. The predictive value was unaffected by treatment intervention. Follow-up MR imaging was most informative after 9 months in patients without dissemination in space at baseline.

Background: To diagnose multiple sclerosis (MS), evidence for dissemination in space and time is required. There is no clear definition on how symptoms and signs of a patient indicate clinical dissemination in space. To provide a uniform approach on this subject, a clinical classification system was described recently differentiating patients with mono- and multifocal clinical presentation. Here we assess the predictive value of clinically defined dissemination in space at first presentation for time to clinically definite MS (CDMS)., Methods: Four hundred and sixty-eight patients with a first episode suggestive of MS were classified as clinically mono- or multifocal by two neurologists blinded to magnetic resonance imaging (MRI) results. These patients were part of the BENEFIT study in which 292 patients were randomized to interferon beta-1b (IFNB-1b) and 176 to placebo. By using Kaplan-Meier statistics the risk for CDMS was studied in mono- and multifocal patients of the placebo group, both with and without taking into account MRI measures of potential prognostic relevance., Results: Time to CDMS was similar in monofocal and multifocal patients. In monofocal patients, the risk for CDMS over 2 years was significantly higher when >or= 9 T2 lesions or at least one Gd-enhancing lesion were present at the first event or 3 or 6 months after the first event. In patients with multifocal presentation, these MRI measures had no significant added value in predicting time to CDMS., Conclusion: These data indicate that a carefully performed neurological assessment of symptoms and signs, combined with lesions on MRI, is important for defining the risk of conversion to CDMS., Trial Registration: The Benefit trial has been registered under NCT00185211 http://www.clinicaltrials.gov.

Purpose: To explore the applicability of subtraction magnetic resonance (MR) images to (a) detect active multiple sclerosis (MS) lesions, (b) directly quantify lesion load change, and (c) detect treatment effects (distinguish treatment arms) in a placebo-controlled multicenter clinical trial by comparing the subtraction scheme with a conventional pair-wise comparison of nonregistered MR images., Materials and Methods: Forty-six pairs of MR studies in 40 patients (31 women; mean age, 31.9 years) from a multicenter clinical trial were used. The clinical trial was approved by local ethics review boards, and all subjects gave written informed consent. Active MS lesions were scored by two independent raters, and lesion load measurements were conducted by using semiautomated software. Lesion counts were evaluated by using the Wilcoxon signed rank test, interrater agreement was evaluated by using the intraclass correlation coefficient (ICC), and treatment (interferon beta-1b) effect was evaluated by using the Mann-Whitney U test., Results: When subtraction images were used, there was a 1.7-fold increase in the detection of positive active lesions, as compared with native image pairs, and significantly greater interobserver agreement (ICC = 0.98 vs 0.91, P < .001). Subtraction images also allowed direct quantification of positive disease activity, a measure that provided sufficient power to distinguish treatment arms (P = .012) compared with the standard measurement of total lesion load change on native images (P = .455)., Conclusion: MR image subtraction enabled detection of higher numbers of active MS lesions with greater interobserver agreement and exhibited increased power to distinguish treatment arms, as compared with a conventional pair-wise comparison of nonregistered MR images.

Background: MRI is often used as primary outcome measure in phase II clinical trials in multiple sclerosis (MS). Since persistent T1 hypointense lesions are a surrogate parameter for axonal damage and demyelination, they may serve as a marker for monitoring the efficacy of neuroprotective drugs. At present, a power analysis using black hole (BH) evolution as primary outcome measure has not been performed., Objective: To assess the feasibility of using BH evolution on serial brain MR images as primary outcome measure in proof of concept studies in MS., Methods: MRI-data obtained from 169 active RRMS patients were analysed for BH evolution by determining the cumulative number of contrast enhancing lesions (CEL) evolving into a persistent black hole (PBH) after 3 months. With a parametric simulation procedure, based on a statistical distribution fitting the data, sample sizes were calculated., Results: 21.2% of the total number of CELs observed during the study period evolved into a PBH. Ring enhancing lesions evolved most frequently into a PBH (59.4%), followed by lesions larger than 10 mm (57.4%) and periventricular CELs (30.6%). The simulation procedure, based on the statistical negative binomial (NB) model resulted in a sample sizes between 200 subjects and 30 subjects per arm, for treatment effects ranging from 50% to 90% reduction of the number of CELs evolving into a PBH, respectively., Conclusion: To perform a MRI monitored phase II clinical trial with a feasible sample size, using the evolution of CELs into PBHs as primary outcome parameter, a potent drug is required to obtain sufficient power.

Hirayama's disease is a benign juvenile form of focal amyotrophy affecting the upper limbs. Previous studies have suggested that the disorder is a neck flexion induced cervical myelopathy. We report clinical and magnetic resonance imaging findings in nine patients with Hirayama's disease. Cervical imaging of seven patients revealed spinal cord changes consisting of focal atrophy and foci of signal alterations. On neck flexion a forward movement and mild reduction in the anteroposterior diameter of the lower cervical cord against the vertebral bodies was noted in affected individuals as well as in five normal controls. In contrast to earlier reports, none of our patients showed complete obliteration of the posterior subarachnoid space. Measurement of the anteroposterior spinal cord diameter in each vertebral segment (C4-C7) revealed no significant differences in the degree of spinal cord flattening between the two groups. Furthermore, two of our patients had significant degenerative changes in the cervical spine (disc herniation, retrospondylosis) contralateral to the clinically affected side. These degenerative changes resulted in a marked cord compression on neck flexion but were not associated with ipsilateral clinical abnormalities or spinal cord alterations. Our results argue against a flexion-induced cervical myelopathy and support the view that Hirayama's disease is an intrinsic motor neuron disease.

Purpose: To optimize detection and diagnosis of breast lesions with contrast-enhanced magnetic resonance (MR) imaging., Materials and Methods: A three-dimensional fast low-angle shot pulse sequence was used for a group comparison consisting of 76 high-dose (0.16 mmol gadopentetate dimeglumine per kilogram of body weight) and 76 low-dose (0.1 mmol/kg) examinations. Intraindividual comparisons were possible in a subgroup of 20 patients., Results: Enhancement with the high dose was about 1.5 times higher for benign and malignant tissues. With the lower dose, no false-positive findings could be avoided and definition of a threshold that excluded false-negative findings was problematic. Conspicuity of malignant lesions was much improved with the higher dose (a good to excellent rating in 81% vs 26% with the lower dose). Three small foci were visible only with the higher dose., Conclusion: The higher dose of contrast material allowed much better results. Dose comparison studies are also recommended for other techniques.

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. [ABSTRACT FROM AUTHOR]

Background Recently, a clinical classification system was described to determine whether symptoms and signs of patients presenting with a first episode suggestive of multiple sclerosis (MS) indicate the presence of monofocal or multifocal disease. Objectives To evaluate the value of this new classification system by comparing the results with those of simultaneously obtained magnetic resonance imaging (MRI) scans. Methods The 487 patients, randomised in the BENEFIT study, were centrally assessed using the new system and classified as monofocal or multifocal, based on clinical information by two neurologists masked for the MRI results. MRI analyses were performed by expert readers masked for the clinical classification. Results Patients classified as multifocal had more T2 hyperintense (median: 21 versus 15.5) and more T1 hypo-intense lesions (median: 2 versus 1) than those classified as monofocal. Patients classified at the local site as having evidence of a single clinical lesion, but reclassified centrally as having a clinical multifocal central nervous system presentation, had more T2 lesions than monofocal patients. In addition, patients with a multifocal presentation more often fulfilled the MRI criteria for dissemination in space, as incorporated in the International Panel (IP) diagnostic criteria for MS. Conclusion These data provide justification for the recently proposed clinical classification system to be used in patients who present with a first episode suggestive of MS, in that ‘multifocal’, based on symptoms and signs, is associated with more lesions on MRI. [ABSTRACT FROM AUTHOR]

Background & Objective: No clinical study of any interferon beta therapy has yet been successfully conducted in Chinese multiple sclerosis patients, probably due to the low incidence of this disease in China. The primary objective of this study was to demonstrate that treating multiple sclerosis patients of Chinese origin with interferon beta-1b has a beneficial effect on disease course, as measured by the decrease of newly active lesions on magnetic resonance imaging. Methods: Chinese patients diagnosed with relapsing-remitting or secondary-progressive multiple sclerosis were enrolled in this multicenter, open label, single-arm study. Following a 3-month pre-treatment phase, patients were treated with 250 μg interferon beta-1b subcutaneously every other day for 6 months. Patients had regular assessments for treatment safety and efficacy of the treatment. Results: Thirty seven patients completed the trial. Significant decreases in the number of newly active lesions were observed in the 6-month treatment period compared with the pre-treatment period (median decrease 1.5 lesions, p<0.001). Most adverse events were mild and transient and no serious ones were observed. Conclusions: Treatment with interferon beta-1b significantly reduced the occurrence of new lesions and was well tolerated in this Chinese population. These findings support the use of interferon beta- 1b for treating Chinese MS patients. [ABSTRACT FROM AUTHOR]