Modification of MRI criteria for multiple sclerosis in patients with clinically isolated syndromes

Background

The McDonald criteria include MRI evidence for dissemination in space and dissemination in time for the diagnosis of multiple sclerosis in young adult patients who present with clinically isolated syndromes (CIS) typical of the disease. Although a major advance, the criteria have limited sensitivity for making an early diagnosis.

Objective

To compare the performance of McDonald criteria and modified McDonald criteria for dissemination in space and time for assessing the development of clinically definite multiple sclerosis.

Methods

McDonald criteria were modified using the combination of a less stringent definition for dissemination in space and allowing a new T2 lesion per se after three months as evidence for dissemination in time. Modified and McDonald criteria were applied in 90 CIS patients at baseline and at three month follow up scans.

Results

Both criteria were highly specific (>90%) but the modified criteria were more sensitive (77% v 46%) and more accurate (86% v 73%).

Conclusions

These modified criteria should be evaluated in other CIS cohorts.     

Prospective combined brain and spinal cord MRI in clinically isolated syndromes and possible early multiple sclerosis: impact on dissemination in space and time

Background: The diagnosis of multiple sclerosis (MS) is based on dissemination in space (DIS) and time (DIT). The aim of the study was to assess the impact of spinal cord (SC) imaging on the evidence of DIS and DIT. Methods: Thirty‐five treatment‐naive patients with a first clinical symptom suggestive of MS were examined in a 2‐year prospective longitudinal follow‐up assessment. Brain and SC magnetic resonance imaging (MRI), Expanded Disability Status Scale and multiple sclerosis functional composite were analysed at baseline and after 1 and 2 years. Results: At study entry, 21 patients were classified as clinically isolated syndrome suggestive of MS (CIS) and 14 patients as possible early MS. SC lesions were detected at baseline in 14 CIS patients (67%, median: 1.0, enhancing 29%) and in 11 patients with possible early MS (79%, median: 2.0, enhancing 29%). DIS as depicted by additive SC imaging was detected in two additional individuals according to the revised versus the 2001 McDonald criteria. All patients with emerging cord lesions showed new brain lesions. Five individuals developed clinically asymptomatic cord lesions. Conclusions: Spinal cord abnormalities are frequent in CIS patients and in patients with possible early MS. SC imaging slightly improved the establishment of DIS, but had no impact on the evidence of DIT.     

The Relationship between inflammation and atrophy in clinically isolated syndromes suggestive of multiple sclerosis

Abstract.Objective: To examine the relationship between inflammation and brain atrophy in patients with a clinically isolated syndrome (CIS) suggestive of multiple sclerosis (MS).Methods: Monthly triple-dose gadolinium (Gd/DTPA)-enhanced MRI scans over 6 months were obtained in 62 consecutive CIS patients with an abnormal baseline MRI scan. Subsequently MRI was performed at months 12 and 18. Patients who developed a clinically definite MS (i. e., a second clinical episode) ended the study at the time of the relapse. For each scan, the number and volume of newly active lesions (Gd-enhancement/new or newly enlarging T2 lesion that did not enhance), and the number and volume of T2 hyperintense lesions (T2-LL) and T1-black holes (T1- LL) were calculated. The percentage of brain volume changes (PBVC) was assessed using a fully automated technique (SIENA; Structural Image Evaluation using Normalization of Atrophy).Results: Twenty-four (39%) developed clinically definite MS by month 18. Thirty-eight (61%) were relapsefree and completed the MRI follow-up. Relapse-free patients showed a progressive median increase between baseline and month 18 in T1-LL (25%, p < 0.001), but not in T2-LL (8.5%, p = ns). PBVC decreased by 1.1% (p < 0.001) in a time-dependent pattern (Kendall coefficient of concordance = 0.85). Exploratory subgroup analyses showed a trend towards progressive decreases in brain volume in active patients (i. e., those with at least one newly active lesion during monthly MRI scanning; Spearmans R = –0.61; p < 0.001), but not among inactive patients (Spearmans R = –0.10; p = 0.53). Significant differences in median brain volume changes between the active and inactive patient groups were found at months 12 and 18; the difference detected at month 6 was not significant. The cumulative number and volume of new Gd-enhancing lesions developed during the 6 months of frequent MRI scanning were highly correlated with PBVC over the 18-month period (Spearman R values were 0.73 and 0.85, respectively). The strongest predictor of PBVC at 18 months was the cumulative volume of newly active lesions during frequent MRI scanning [ß = –0. 83, standard error (SE) = 0.07, p < 0.001].Conclusions: This study shows that visible inflammation as detected by monthly, triple-dose Gd-enhanced MRI is an important factor in the pathogenesis of brain tissue loss in CIS patients. However, inflammation and brain atrophy do not proceed in parallel: atrophy appeared only after a delay of months following acute inflammation. Frequent MRI scanning allows for the detection of CIS patients who will develop brain atrophy in the short-term.     

A brain magnetization transfer MRI study with a clinical follow up of about four years in patients with clinically isolated syndromes suggestive of multiple sclerosis

Whereas it is important to gain prognostic information in patients with clinically isolated syndromes (CIS) suggestive of multiple sclerosis (MS), there is still a lack of definitive data about the significance of normal-appearing white (NAWM) and gray (NAGM) matter damage in these patients. The aim of this study was to clarify the role of magnetization transfer magnetic resonance imaging (MT MRI) in assessing “occult” damage at the earliest clinical stage of MS. Dual echo, post-contrast T1-weighted, and MT MRI were obtained from 43 CIS patients with paraclinical evidence of spatial disease dissemination within 3 months from disease onset and from 22 controls. In patients, conventional MRI was obtained after 3 and 12 months from the baseline assessment, to detect disease dissemination in time (DIT). A neurological examination was also conducted to ascertain the occurrence of relapses for an average follow up period of 1389 (range = 420–1847) days. MTR maps were derived and NAWM and NAGM MT ratio (MTR) histograms were analyzed. During the follow up, 30 patients showed MRI evidence of DIT, and 21 experienced a relapse. T2 lesion volume (LV) was significantly higher in patients with DIT than in those without (p = 0.005). MTR histogram variables did not significantly differ between patients with MRI or clinical DIT. T2 LV was the only significant predictor of clinical DIT at follow-up (p = 0.001). This study shows that MT MRI-detectable damage to NAWM and NAGM may not be an important feature of all patients at presentation with a CIS highly suggestive of MS and that such a damage may develop with subsequent disease evolution. Received in revised form: 14 April 2006     

High field MR imaging and <Superscript>1</Superscript>H-MR spectroscopy in clinically isolated syndromes suggestive of multiple sclerosis

Purpose To prospectively investigate metabolic changes in the normal-appearing white matter (NAWM) of patients presenting with clinically isolated syndromes (CIS) suggestive of multiple sclerosis (MS) and to correlate these changes to conventional MR imaging findings in terms of MR imaging criteria. Materials and methods Multisequence MR imaging of the brain and ¹H-MR spectroscopy of the parietal NAWM were performed in 31 patients presenting with CIS and in 20 controls using a 3. 0 T MR system. MR imaging criteria and International Panel criteria were assessed based on imaging, clinical and paraclinical results. Metabolite ratios and absolute concentrations of N-acetyl-aspartate (tNAA), myoinositol (Ins), choline (Cho), and total creatine (tCr) were determined. The metabolite concentrations were correlated with the fulfilled MR imaging criteria. Results In comparison to the control group, the CIS group showed significantly decreased mean tNAA concentrations (–8. 1%, p = 0. 012). Significant changes could not be detected regarding Ins, tCr and Cho. No significant correlations between absolute metabolite concentrations and MR imaging criteria were observed. Patients with and without a lesion dissemination in space showed no significant differences of their metabolite concentrations. Conclusion As assessed by ¹H-MRS a significant axonal damage already occurs during the first demyelinating episode in patients with CIS. Conventional MR imaging in terms of diagnostic imaging criteria does not significantly reflect NAWM disease activity in terms of metabolic alterations detected by ¹H-MR spectroscopy.     

Antimyelin antibodies in clinically isolated syndromes correlate with inflammation in MRI and CSF

OBJECTIVE: We investigated the correlation of antimyelin oligodendrocyte glycoprotein-(anti-MOG) and anti-myelin basic protein antibodies (anti-MBP) in serum of CIS patients with inflammatory signs in MRI and in CSF and, as previously suggested,the incidence of more frequent and rapid progression to clinically definite MS (CDMS). METHODS: 133CIS patients were analysed for anti-MOG and anti-MBP (Western blot). Routine CSF and cranial MRI (quantitatively and qualitatively) measures were analyzed. 55 patients had a follow-up of at least 12 months or until conversion to CDMS. RESULTS: Patients with anti-MOG and anti-MBP had an increased intrathecal IgG production and CSF white blood cell count(p = 0.048 and p = 0.036). When anti-MBP alone, or both antibodies were present the cranial MRI showed significantly more T2 lesions (p = 0.007 and p = 0.01,respectively). There was a trend for more lesion dissemination in anti-MBP positive patients (p = 0.076).Conversely, anti-MOG- and/or anti-MBP failed to predict conversion to CDMS in our follow-up group (n = 55). Only in female patients with at least one MRI lesion (n = 34) did the presence of anti-MOG correlate with more frequent (p = 0.028) and more rapid (p = 0.0209) transition to CDMS. CONCLUSIONS: Presence of anti-MOG or anti-MBP or both was not significantly associated with conversion to CDMS in our CIS cohort. However, patients with anti-MOG and anti-MBP had higher lesion load and more disseminated lesions in cranial MRI as well as higher values for CSF leucocytes and intrathecal IgG production. Our data support a correlation of anti-MOG and anti-MBP to inflammatory signs in MRI and CSF. The prognostic value of these antibodies for CDMS, however, seems to be less pronounced than previously reported.     

Depressive symptoms and MRI changes in multiple sclerosis

To determine whether changes in specific regions of the brain can contribute to the development of depression in patients with multiple sclerosis (MS). We prospectively studied 90 patients with clinically definite MS. Disability, independence, cognitive performances, and depressive and anxiety symptoms have been assessed at baseline and 2 years later. At these two time-points, patients underwent a 1.5-T magnetic resonance examination of the brain including T1- and T2-weighted images. Calculation of regional and total lesion loads (LL) have been performed by a semiautomatic technique; total and regional brain volumes have been calculated by a fully automatic highly reproducible computerized interactive program. Measurements of LL did not show any significant difference between depressed and non-depressed patients. Brain atrophy was significantly more conspicuous in the left frontal lobe (P=0.039), in both frontal lobes (P=0.046) and showed a trend towards a difference in the right frontal lobe (P=0.056), in the right temporal lobe (P=0.057) and in both temporal lobes (P=0.072) of depressed patients. Disability, independence and cognitive performances were similar in depressed and non-depressed patients (P=NS). Spearman correlation analysis and multiple-regression analysis demonstrated that the severity of the depressive symptoms score was associated both with the disability score and the right temporal brain volume. Destructive lesions in the right temporal lobe can contribute to the severity of depression in patients with MS but the influence of the severity of neurological impairment should be taken into account.     

A multicentre study of motor functional connectivity changes in patients with multiple sclerosis

In this multicentre study involving eight European centres, we characterized the spatial pattern of functional connectivity (FC) in the sensorimotor network from 61 right-handed patients with multiple sclerosis (MS) and 74 age-matched healthy subjects assessed with the use of functional magnetic resonance imaging (fMRI) and a simple motor task of their right dominant hand. FC was investigated by using: (i) voxel-wise correlations between the left sensorimotor cortex (SMC) and any other area in the brain; and (ii) bivariate correlations between time series extracted from several regions of interest (ROIs) belonging to the sensorimotor network. Both healthy controls and MS patients had significant FC between the left SMC and several areas of the sensorimotor network, including the bilateral postcentral and precentral gyri, supplementary motor area, middle frontal gyri, insulae, secondary somatosensory cortices, thalami, and right cerebellum. Voxel-wise assessment of FC revealed increased connectivity between the left SMC and the right precentral gyrus, right middle frontal gyrus (MFG) and bilateral postcentral gyri in MS patients as compared with controls. ROI analysis also showed a widespread pattern of altered connectivity, characterized by increased FC between the right MFG, the left insula and the right inferior frontal gyrus in comparison with many regions of the sensorimotor network. These results provide further evidence for increased bihemispheric contributions to motor control in patients with MS relative to healthy controls. They further suggest that multicentre fMRI studies of FC changes are possible, and provide a potential imaging biomarker for use in experimental therapeutic studies directed at enhancing adaptive plasticity in the disease.     

Linking structural, metabolic and functional changes in multiple sclerosis

In patients with multiple sclerosis (MS), conventional magnetic resonance imaging (MRI) has markedly improved our ability to detect the macroscopic abnormalities of the brain and spinal cord. New quantitative magnetic resonance (MR) approaches with increased sensitivity to subtle normal-appearing white matter (NAWM) and grey matter changes and increased specificity to the heterogeneous pathological substrates of MS may give information complementary to conventional MRI. Magnetization transfer imaging (MTI) and diffusion-weighted imaging (DWI) have the potential to provide important information on the structural changes occurring within and outside T2-visible lesions. Magnetic resonance spectroscopy (MRS) adds information on the biochemical nature of such changes. Functional MRI might quantify the efficiency of brain plasticity in response to MS injury and improve our understanding of the link between structural damage and clinical manifestations. The present review summarizes how the application of these MR techniques to the study of MS is dramatically changing our understanding of how MS causes irreversible neurological deficits.     

Blood cholesterol and MRI activity in first clinical episode suggestive of multiple sclerosis

OBJECTIVES: The present study was planned to investigate the relationship between the plasma lipid profile and disease activity in patients with a first clinical episode suggestive of multiple sclerosis (MS). MATERIAL AND METHODS: Eighteen consecutive out-patients underwent a monthly brain magnetic resonance imaging (MRI), blood sample and neurological assessment over 6 months. Blood samples were used to evaluate total cholesterol and triglyceride levels as well as their lipoprotein fractions. Plasma total apolipoprotein E concentration was also determined. RESULTS: We found a significant correlation between the mean number of enhancing lesions and the mean plasma level of both total and low density lipoprotein cholesterol. The total plasma cholesterol level increased on average by 4.4 mg/dl for each enhancing lesion. CONCLUSION: Our preliminary data suggest a potential role of plasma cholesterol level as a biological marker of disease activity after a first demyelinating event. Further studies need, however, to be designed to determine whether the plasma cholesterol level is of practical use in monitoring the disease course.     

Magnetic resonance study of the influence of tissue damage and cortical reorganization on PASAT performance at the earliest stage of multiple sclerosis

We sought to determine the influence of tissue damage and the potential impact of cortical reorganization on the performance to the Paced Auditory Serial Addition Test (PASAT) in patients at the earliest stage of multiple sclerosis (MS). Magnetization transfer ratio (MTR) imaging and functional magnetic resonance imaging (fMRI) experiments using PASAT as paradigm were carried out in 18 patients with clinically isolated syndrome suggestive of MS (CISSMS) compared to 18 controls. MTR histogram analyses showed structural abnormalities in patients involving the normal-appearing white matter (NAWM) but also the gray matter (GM). Mean PASAT scores were significantly lower in the group of patients taken as a whole, and were correlated with the mean NAWM MTR value. No correlation was observed between PASAT scores and GM MTR. However, in the subgroup of patients with normal PASAT performance (n = 9), fMRI showed larger activations in bilateral Brodmann area 45 (BA45) and right BA44 compared to that in controls (n = 18). In these areas with potentially compensatory reorganization, the whole group of patients (n = 18) showed significantly greater activation than controls (n = 18). Activation in the right BA45 was inversely correlated with the mean NAWM MTR and the peak position of GM MTR histograms of patients. This study indicates that even at the earliest stage of MS, cortical reorganization is present inside the executive system of working memory and could tend to limit the determinant functional impact of NAWM injury on the execution of the PASAT.     

Functional adaptive changes within the hippocampal memory system of patients with multiple sclerosis

Memory deficits are highly prevalent in multiple sclerosis (MS). As the hippocampus is crucial to memory processing, a functional magnetic resonance imaging (fMRI) task was used to investigate changes in hippocampal function in MS patients with and without cognitive decline. Fifty patients with MS, (34 cognitively preserved (CP) and 16 cognitively impaired (CI)) and 30 healthy controls completed an episodic memory fMRI task (encoding and retrieval) that was used to specifically activate the hippocampus. During encoding of correctly remembered items, increased brain activation was seen in the parahippocampal areas bilaterally and in the left anterior cingulate gyrus in the CP patients compared to the controls (unclustered, Z ≥ 3.1, P ≤ 0.001). No brain areas showed less activation. In CI patients the right (para)hippocampal areas and the prefrontal cortex showed less brain activation compared to controls (cluster-corrected, P < 0.05). The posterior cingulate gyrus and the left precuneus showed increased activation in CI patients when compared to controls (unclustered Z ≥ 3.1, P ≤ 0.001). No significant differences were found on structural MRI measures between the CP and CI patients. These results suggest the presence of functional adaptation in the memory network before cognitive decline becomes evident in MS, as displayed by the increased brain activation in the hippocampal-cingulate memory system in CP patients. Interestingly, CI patients showed less activation in the hippocampal network during correct encoding. These findings are important for future cognitive therapeutic studies, since cognitive intervention might be most effective before cognitive impairment is present and when adaptive changes of the brain are most prominent.     

Correlation between brain MRI lesion volume and disability in patients with multiple sclerosis

In this study we evaluated the relationships between clinical variables and lesion volumes measured from magnetic resonance imaging (MRI) scans in a large cohort of multiple sclerosis (MS) patients. One hundred and thirty patients with MS entered the study: 36 patients had relapsing-remitting (RR), 39 benign (B), 42 secondary progressive (SP) and 13 primary progressive (PP) courses. There was a significant correlation (r=0.3; p=0.0006) between the total lesion load and the EDSS score when the whole cohort of patients was considered. This correlation increased (r=0.5) when only patients with RRMS and SPMS were considered. Our data indicate that a correlation between disability and MRI lesion volume in MS exists, but its strength is moderate.     

Brain MRI in late-onset multiple sclerosis

Multiple sclerosis (MS) with clinical onset after 50 years of age is unusual (between 1 and 6%) and is frequently misdiagnosed. Furthermore, brain magnetic resonance imaging (MRI) abnormalities are frequently observed in subjects over 50 years of age. The aim of this study was to describe brain MRI in late-onset MS to evaluate the sensitivity and specificity of radiological MS criteria in patients aged over 50 years. We evaluated the brain MRI of 20 patients with onset of MS after 50 years of age. We compared these MRI with 26 controls matched for age, sex and vascular risk factors. MRI were blindly analysed by two neuroradiologists according to Paty et al.'s [Neurology38 (1988) 180] criteria, Fazekas et al.'s [Neurology38 (1988) 1822] criteria and Barkhof et al.'s [Brain120 (1997) 2059] criteria. The mean age at MRI scanning was 58 years. Sensitivity was 90% for Paty et al.'s criteria, 80% for Fazekas et al.'s criteria and 85% for Barkhof et al.'s criteria. Specificity was 54% for Paty et al.'s criteria, 69% for Fazekas et al.'s criteria and 65% for Barkhof et al.'s criteria. Barkhof et al.'s criteria are less specific in older patients than in young patients. We suggest that spinal cord MRI and cerebrospinal fluid analysis should be systematically performed in suspected late-onset MS in order to increase the specificity of the diagnosis.     

Acute disseminated encephalomyelitis that meets modified McDonald criteria for dissemination in space is associated with a high probability of conversion to multiple sclerosis in Taiwanese patients

Background: Patients with acute disseminated encephalomyelitis (ADEM) may relapse and some may ultimately convert to multiple sclerosis (MS); however, no criteria that can predict MS conversion are available to date. Our aim was to describe the clinical and magnetic resonance imaging (MRI) features of patients with an initial ADEM attack and evaluate which MRI criteria can predict conversion to MS. Methods: We retrospectively reviewed the records of 36 patients diagnosed with ADEM. We determined clinical signs/symptoms, examined the cerebrospinal fluid (CSF), and performed brain MRI scans and compared the findings between patients who did and did not convert to MS. Results: Clinical signs/symptoms, and CSF analysis show no significant difference between the two groups. The rate of conversion to MS from ADEM in Taiwanese patients is low (11%) after a mean follow‐up period of 28.36 months. Modified McDonald criteria were fulfilled in 19/36 patients: 21% (4/19) of those patients developed MS according to Poser criteria subsequently. Of the other patients (17/36) who did not fulfill these criteria, none converted to MS. (log rank test; P = 0.027). Conclusions: It is difficult to predict from initial clinical presentations to address which patients with ADEM will convert to MS. Patients with ADEM whose brain MRI findings met the modified McDonald criteria may have clinically isolated syndrome because they have a significantly higher probability of conversion to MS. In contrast, patients whose brain MRI findings did not meeting these criteria may be considered as having classic ADEM because they have a lower probability of conversion to MS.     

Compensatory activations in patients with multiple sclerosis during preserved performance on the auditory N-back task

Recent fMRI studies have suggested that multiple sclerosis (MS) patients show adaptive cortical changes (i.e., compensatory mechanisms) during motor and cognitive tasks to limit the clinical impact of tissue injury. In this study, we investigated the activation pattern during the auditory n-back working memory (WM) paradigm in a group of 17 MS patients and 10 healthy controls with preserved performance in WM tasks. Compared with healthy controls, MS patients showed significantly greater bilateral activation in prefrontal cortex (BA 44), and the insula. These findings were similar to those obtained in previous studies showing that compensatory mechanisms during WM tasks in MS may be based on the use of prefrontal areas adjacent to those involved in the task.