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A J Thompson

Publications and source records attributed to A J Thompson.

At least 37 records · Page 2Linked to original sources
PubMed2005

Magnetization transfer histograms in clinically isolated syndromes suggestive of multiple sclerosis.

In established multiple sclerosis, magnetization transfer ratio (MTR) histograms reveal abnormalities of normal-appearing white matter (NAWM) and grey matter (NAGM). The aim of this study was to investigate for such abnormalities in a large cohort of patients presenting with clinically isolated syndromes suggestive of multiple sclerosis. Magnetization transfer imaging was performed on 100 patients (67 women, 33 men, median age 32 years) a mean of 19 weeks (SD 3.8, range 12-33 weeks) after symptom onset with a clinically isolated syndrome and in 50 healthy controls (34 women, 16 men, median age 32.5 years). SPM99 software was used to generate segmented NAWM and NAGM MTR maps. The volumes of T2 lesions, white matter and grey matter were calculated. Eighty-one patients were followed up clinically and with conventional MRI after 3 years (n = 61) or until they developed multiple sclerosis if this occurred sooner (n = 20). Multiple regression analysis was used to investigate differences between patients and controls with age, gender and volume measures as covariates to control for potential confounding effects. The MTR histograms for both NAWM and NAGM showed a reduction in the mean (NAWM, 38.14 versus 38.33, P = 0.001; NAGM 32.29 versus 32.50, P = 0.009; units in pu) and peak location, with a left shift in the histogram. Mean NAWM and NAGM MTR were also reduced in the patients who developed clinically definite multiple sclerosis and multiple sclerosis according to the McDonald criteria but not in the 24 patients with normal T2-weighted brain magnetic resonance imaging (MRI). MTR abnormalities occur in the NAWM and NAGM at the earliest clinical stages of multiple sclerosis.

Adult↗
PubMed2005

Long-term clinical outcome of primary progressive MS: predictive value of clinical and MRI data.

The authors sought to identify clinical and MRI predictors of outcome in primary progressive multiple sclerosis (PPMS). Clinical and MRI assessments were performed at baseline and 2 and 5 years (clinical only). At baseline, disease duration, expanded disability status scale (EDSS) and brain volume predicted outcome. Adding short-term change variables, baseline EDSS, changes in T2* lesion load and cord area, and number of new lesions were predictive. Clinical and MRI variables predict long-term outcome in PPMS.

Atrophy↗
PubMed2005

A longitudinal study of cognition in primary progressive multiple sclerosis.

There are few longitudinal studies of cognition in patients with multiple sclerosis, and the results of these studies remain inconclusive. No serial neuropsychological data of an exclusively primary progressive series are available. Cross-sectional analyses have revealed significant correlations between cognition and magnetic resonance imaging (MRI) parameters in primary progressive multiple sclerosis (PPMS). This study investigated cognitive and MRI change in 99 PPMS patients from five European centres for 2 years. They were assessed at 12 month intervals using the Brief Repeatable Battery, a reasoning test, and a measure of depression. The MRI parameters of T1 hypointensity load, T2 lesion load, and partial brain volume were also calculated at each time point. There were no significant differences between the mean cognitive scores of the patients at year 0 and year 2. However, one-third of the patients demonstrated absolute cognitive decline on individual test scores. Results indicated that initial cognitive status on entry into the study was a good predictor of cognitive ability at 2 years. There was only a small number of significant correlations between changes in cognition and changes on MRI, notably T1 hypointensity load with the two attentional tasks (r = -0.266, P = 0.017; r = -0.303, P = 0.012). It is probable that multiple factors underlie this weak relation between the cognitive and MRI measures.

Adult↗
PubMed2005

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.

Cohort Studies↗
PubMed2005

Identifying brain regions for integrative sensorimotor processing with ankle movements.

The objective of this study was to define cortical and subcortical structures activated during both active and passive movements of the ankle, which have a fundamental role in the physiology of locomotion, to improve our understanding of brain sensorimotor integration. Sixteen healthy subjects, all right-foot dominant, performed a dorsi-plantar flexion task of the foot using a custom-made wooden manipulandum, which enabled measurements of the movement amplitude. All subjects underwent a training session, which included surface electromyography, and were able to relax completely during passive movements. Patterns of activation during active and passive movements and differences between functional MRI (fMRI) responses for the two types of movement were assessed. Regions of common activation during the active and passive movements were identified by conjunction analysis. We found that passive movements activated cortical regions that were usually similar in location to those activated by active movements, although the extent of the activations was more limited with passive movements. Active movements of both feet generated greater activation than passive movements in some regions (such as the ipsilateral primary motor cortex) identified in previous studies as being important for motor planning. Common activations during active and passive movements were found not only in the contralateral primary motor and sensory cortices, but also in the premotor cortical regions (such as the bilateral rolandic operculum and contralateral supplementary motor area), and in the subcortical regions (such as the ipsilateral cerebellum and contralateral putamen), suggesting that these regions participate in sensorimotor integration for ankle movements. In future, similar fMRI studies using passive movements have potential to elucidate abnormalities of sensorimotor integration in central nervous system diseases that affect motor function.

Adult↗
PubMed2005

Increasing normal-appearing grey and white matter magnetisation transfer ratio abnormality in early relapsing-remitting multiple sclerosis.

Abnormalities within normal-appearing grey and white matter (NAGM and NAWM) occur early in the clinical course of multiple sclerosis (MS) and can be detected in-vivo using the magnetisation transfer ratio (MTR). To better characterize the rates of change in both tissues and to ascertain when such changes begin, we serially studied a cohort of minimally disabled, early relapsing-remitting MS patients, using NAGM and NAWM MTR histograms. Twenty-three patients with clinically definite early relapsing-remitting MS (mean disease duration at baseline 1.9 years), and 19 healthy controls were studied. A magnetisation transfer imaging sequence was acquired yearly for two years. Twenty-one patients and 10 controls completed followup. NAWM and NAGM MTR histograms were derived and mean MTR calculated. A hierarchical regression analysis, adjusting for brain parenchymal fraction,was used to assess MTR change over time. MS NAWM and NAGM MTR were significantly reduced in comparison with controls at baseline and, in patients, both measures decreased further during follow-up: (-0.10 pu/year, p=0.001 and -0.18 pu/year, p<0.001 respectively). The rate of MTR decrease was significantly greater in NAGM than NAWM (p=0.004). Under the assumption that such changes are linear, backward extrapolation of the observed rates of change suggested that NAWM abnormality began before symptom onset. We conclude that increasing MTR abnormalities in NAWM and NAGM are observed early in the course of relapsing-remitting MS. It is now important to investigate whether these measures are predictive of future disability, and consequently, whether MTR could be used as a surrogate marker in therapeutic trials.

Adult↗
PubMed2005

Interferon beta-1b treatment does not induce autoantibodies.

BACKGROUND: There is little information regarding the potential of interferon beta (IFNbeta) to induce or exacerbate autoimmune disease. Existing data from uncontrolled studies are contradictory and do not differentiate between autoimmune dysfunction, which is frequent in patients with multiple sclerosis (MS), and untoward drug effects. OBJECTIVE: To evaluate the impact of IFNbeta on hepatic, thyroid, and other markers of autoimmunity using data from the European placebo-controlled double-blind, multicenter study of IFNbeta-1b in patients with secondary progressive MS (SPMS). METHODS: Serum samples obtained at baseline and at 6-month intervals for 24 months were analyzed for the following autoantibodies (AAbs): antinuclear (ANA), antimitochondrial (AMA), smooth muscle (SMA), liver kidney microsome (LKM), thyroid microsome (TPO), and human thyroglobulin (TG). AAb status at baseline and during treatment was related to respective laboratory and clinical deviations. RESULTS: The analysis of AAb data included 355 patients receiving IFNbeta-1b and 353 receiving placebo. There was no difference between treatment groups in de novo AAb positivity. A greater proportion of women were AAb positive at baseline and during treatment. No association was found between liver enzyme elevations and ANA, AMA, or SMA antibody formation in either treatment group. Laboratory-based thyroid alterations during the study were significantly related to TG/TPO status at baseline but were not associated with IFNbeta-1b treatment. Adverse events possibly indicative of other diseases with autoimmune links were not associated with respective AAb status. CONCLUSION: Interferon beta-1b treatment did not induce autoantibody formation in this population of patients with secondary progressive multiple sclerosis.

Autoantibodies↗
PubMed2005

Gray and white matter volume changes in early RRMS: a 2-year longitudinal study.

BACKGROUND: Brain atrophy, in excess of that seen with normal aging, has been observed early in the clinical course of relapsing-remitting multiple sclerosis (RRMS). Previous work has suggested that at this stage of the disease, gray matter (GM) atrophy progresses more rapidly than the white matter (WM) atrophy. OBJECTIVES: To characterize the evolution of GM and WM volumes over 2 years, and their associations with lesion loads in a cohort of patients with clinically early RRMS. METHODS: Twenty-one patients with RRMS (mean age 37.5 years, mean disease duration from symptom onset 2.1 years) and 10 healthy control subjects (mean age 37.1 years) were studied. Tissue volumes, as fractions of total intracranial volumes, were estimated at baseline and 1- and 2-year follow-up. Brain parenchymal fractions (BPF), GM fractions (GMF), and WM fractions (WMF) were estimated. In subjects with MS, brain lesion loads were determined on conventional T2-weighted along with pre- and post-gadolinium (Gd) enhanced T1-weighted images at each timepoint. RESULTS: A decrease in GMF was observed in subjects with MS vs normal controls over the 2 years of the study (mean -2.1% vs -1.0%, p = 0.044), while no change was seen in WMF over the same period (mean -0.09% vs +0.09%, p = 0.812). However, when the MS cohort was divided in half, dependent upon change in Gd-enhancing lesion load over 2 years (n = 20), a decrease in WMF was seen in the group (n = 10) with the largest decline in Gd volume, whereas WMF increased in the other half (n = 10) concurrent with a net increase in volume of Gd-enhancing lesions (difference between groups: p = 0.034). CONCLUSIONS: Increasing gray matter but not white matter (WM) atrophy was observed early in the clinical course of relapsing-remitting multiple sclerosis. Fluctuations in inflammatory WM lesions appear to be related to volume changes in WM over this time period.

Adult↗
PubMed2005

Metabolite changes in normal-appearing gray and white matter are linked with disability in early primary progressive multiple sclerosis.

BACKGROUND: Abnormalities in normal-appearing brain tissues may contribute to disability in primary progressive multiple sclerosis (PPMS), where few lesions are seen on conventional imaging. OBJECTIVES: To evaluate the mechanisms underlying disease progression in the early phase of PPMS by measuring metabolite concentrations in normal-appearing white matter (NAWM) and cortical gray matter (CGM) and to assess their relationship with clinical outcomes. DESIGN: Case-control study. SETTING: Tertiary referral hospital. Patients Forty-three consecutive patients within 5 years of onset of PPMS and 44 healthy control subjects. MAIN OUTCOME MEASURES: Concentrations of choline-containing compounds, phosphocreatine, myo-inositol, total N-acetyl-aspartate (tNAA), and glutamate-glutamine were estimated using proton magnetic resonance spectroscopic imaging. Brain parenchymal, white matter and gray matter fractions and proton density and gadolinium-enhancing lesion loads were calculated. The Expanded Disability Status Scale and Multiple Sclerosis Functional Composite scores were recorded. RESULTS: In CGM, concentrations of the tNAA (P<.001) and glutamate-glutamine (P = .005) were lower in patients with PPMS than in controls. In NAWM, myo-inositol levels were higher (P = .002) and tNAA levels were lower (P = .005) in patients with PPMS than in controls. The Expanded Disability Status Scale score correlated with the tNAA concentration in CGM (r = -0.44; P = .03) and with myo-inositol (r = 0.41; P = .01) and glutamate-glutamine concentrations (r = 0.41; P = .01) in NAWM. Proton density lesion load correlated negatively with CGM tNAA concentration and positively with NAWM myo-inositol concentration. CONCLUSION: Metabolite changes, which differ in CGM and NAWM, occur in early PPMS and are linked with disability.

Adult↗
PubMed2005

An automated approach to connectivity-based partitioning of brain structures.

We present an automated approach to the problem of connectivity-based partitioning of brain structures using diffusion imaging. White-matter fibres connect different areas of the brain, allowing them to interact with each other. Diffusion-tensor MRI measures the orientation of white-matter fibres in vivo, allowing us to perform connectivity-based partitioning non-invasively. Our new approach leverages atlas-based segmentation to automate anatomical labeling of the cortex. White-matter connectivities are inferred using a probabilistic tractography algorithm that models crossing pathways explicitly. The method is demonstrated with the partitioning of the corpus callosum of eight healthy subjects.

Algorithms↗
PubMed2005

Evaluating neurorehabilitation: lessons from routine data collection.

BACKGROUND: Clinical databases are being used increasingly to assess outcomes in healthcare services to provide evidence of clinical effectiveness in routine clinical practice. OBJECTIVES: To explore the benefits of a database for routine collection of clinical outcomes within an inpatient neurorehabilitation setting; determine the effectiveness of inpatient neurorehabilitation in a range of neurological conditions; and determine variables influencing change in functional outcome. METHODS: Over a nine year period, demographic and diagnostic characteristics were collected for the 1458 patients admitted consecutively to a neurorehabilitation unit. The level of function was measured on admission and discharge using the Barthel Index (BI) and Functional Independence Measure (FIM). Patient perception of rehabilitation benefit was evaluated using visual analogue scales (VAS). RESULTS: Of the 1413 patients (mean (SD) age 48 (14.8), range 16 to 87) whose length of stay was more than 10 days (mean 34 (24) range 10 to 184), 282 had stroke, 614 multiple sclerosis, 248 spinal cord injuries, 93 a neuromuscular condition, and 176 other brain pathology. Patients improved in functional ability as measured by both BI and the FIM motor subscale (effect sizes 0.93 to 1.44 and 1.01 to 1.48, respectively). VAS ratings demonstrated high levels of patient perceived benefit. Diagnosis, functional activity score on admission, and length of stay were significant predictors of functional gain, explaining 44% of the variability in the change scores. CONCLUSIONS: Systematic collection, analysis, and interpretation of standardised clinical outcomes data are feasible within routine clinical practice, and provide evidence that inpatient rehabilitation is effective in improving functional level in neurologically impaired patients. These data complement those of clinical trials and are useful in informing and developing clinical and research practice.

Activities of Daily Living↗
PubMed2005

Is inflammation important in early PPMS? a longitudinal MRI study.

BACKGROUND: Magnetic resonance imaging (MRI) studies in primary progressive multiple sclerosis (PPMS) have shown a reduced frequency of enhancement with the contrast agent gadolinium-DTPA (Gd-DTPA), in comparison with relapsing-remitting multiple sclerosis (RRMS), and it has been suggested that there may be a less important role for inflammation in its pathogenesis. However, the earliest clinical stages of PPMS have not been studied and thus it has not been possible to exclude the existence of an early inflammatory phase. OBJECTIVE: To study the presence, characteristics, and implications of inflammation in early PPMS. METHODS: 45 patients with a mean disease duration of 3.3 years had triple dose Gd enhanced MRI, expanded disability status scale (EDSS), and multiple sclerosis functional composite (MSFC) assessments at baseline. Repeat MRI was done at 1 and 2 months in 24 patients, and at 6 months in 38. RESULTS: Enhancing brain lesions were present in 42% of patients at baseline but enhancing cord lesions were uncommon (7%); 85% of enhancing lesions enhanced for one month or less. Patients with enhancing lesions had greater disability (EDSS, p = 0.027; MSFC, p = 0.026) and more MRI abnormalities (greater T2 load, p = 0.008; greater T1 hypointensity load, p = 0.001; and reduced partial brain volume, p = 0.012) than those without enhancement. Enhancement at 6 months was seen in 32% of patients and was restricted to a subset of patients who enhanced at baseline. CONCLUSIONS: Enhancement is present in some cases of early PPMS and is associated with greater disease impact in terms of both clinical and MRI measures.

Adult↗
PubMed2005

How responsive is the Multiple Sclerosis Impact Scale (MSIS-29)? A comparison with some other self report scales.

OBJECTIVES: To compare the responsiveness of the Multiple Sclerosis Impact Scale (MSIS-29) with other self report scales in three multiple sclerosis (MS) samples using a range of methods. To estimate the impact on clinical trials of differing scale responsiveness. METHODS: We studied three discrete MS samples: consecutive admissions for rehabilitation; consecutive admissions for steroid treatment of relapses; and a cohort with primary progressive MS (PPMS). All patients completed four scales at two time points: MSIS-29; Short Form 36 (SF-36); Functional Assessment of MS (FAMS); and General Health Questionnaire (GHQ-12). We determined: (1) the responsiveness of each scale in each sample (effect sizes): (2) the relative responsiveness of competing scales within each sample (relative efficiency): (3) the differential responsiveness of competing scales across the three samples (relative precision); and (4) the implications for clinical trials (samples size estimates scales to produce the same effect size). RESULTS: We studied 245 people (64 rehabilitation; 77 steroids; 104 PPMS). The most responsive physical and psychological scales in both rehabilitation and steroids samples were the MSIS-29 physical scale and the GHQ-12. However, the relative ability of different scales to detect change in the two samples was variable. Differing responsiveness implied more than a twofold impact on sample size estimates. CONCLUSIONS: The MSIS-29 was the most responsive physical and second most responsive psychological scale. Scale responsiveness differs notably within and across samples, which affects sample size calculations. Results of clinical trials are scale dependent.

Adolescent↗
PubMed2005

Cannabinoids in multiple sclerosis (CAMS) study: safety and efficacy data for 12 months follow up.

OBJECTIVE: To test the effectiveness and long term safety of cannabinoids in multiple sclerosis (MS), in a follow up to the main Cannabinoids in Multiple Sclerosis (CAMS) study. METHODS: In total, 630 patients with stable MS with muscle spasticity from 33 UK centres were randomised to receive oral Delta(9)-tetrahydrocannabinol (Delta(9)-THC), cannabis extract, or placebo in the main 15 week CAMS study. The primary outcome was change in the Ashworth spasticity scale. Secondary outcomes were the Rivermead Mobility Index, timed 10 metre walk, UK Neurological Disability Score, postal Barthel Index, General Health Questionnaire-30, and a series of nine category rating scales. Following the main study, patients were invited to continue medication, double blinded, for up to 12 months in the follow up study reported here. RESULTS: Intention to treat analysis of data from the 80% of patients followed up for 12 months showed evidence of a small treatment effect on muscle spasticity as measured by change in Ashworth score from baseline to 12 months (Delta(9)-THC mean reduction 1.82 (n = 154, 95% confidence interval (CI) 0.53 to 3.12), cannabis extract 0.10 (n = 172, 95% CI -0.99 to 1.19), placebo -0.23 (n = 176, 95% CI -1.41 to 0.94); p = 0.04 unadjusted for ambulatory status and centre, p = 0.01 adjusted). There was suggestive evidence for treatment effects of Delta(9)-THC on some aspects of disability. There were no major safety concerns. Overall, patients felt that these drugs were helpful in treating their disease. CONCLUSIONS: These data provide limited evidence for a longer term treatment effect of cannabinoids. A long term placebo controlled study is now needed to establish whether cannabinoids may have a role beyond symptom amelioration in MS.

Administration, Oral↗
PubMed2005

Multiple sclerosis: diagnosis and the management of acute relapses.

Multiple sclerosis is an inflammatory demyelinating disease of the central nervous system that may result in a wide range of neurological symptoms and accumulating disability. Its course is unpredictable resulting in a changing pattern of clinical need. Diagnostic criteria for multiple sclerosis require objective evidence for dissemination in space and time. The diagnostic and management process should follow good practice guidelines with the person at the centre of the process. Appropriate support and information should be available from the time of diagnosis. Continuing education is key in enabling the person to actively participate in their management. In the event of an acute relapse the person should have direct access to the most appropriate local service. Provided medical causes have been excluded, corticosteroid treatment to hasten the recovery from the relapse should be considered. Management of an acute relapse should be comprehensive addressing any medical, functional, or psychosocial sequelae.

Adolescent↗
PubMed2005

Emergence of thalamic magnetization transfer ratio abnormality in early relapsing-remitting multiple sclerosis.

While there is now evidence for thalamic abnormality in established secondary progressive and relapsing-remitting multiple sclerosis (MS), it remains unclear when such abnormality begins. This study investigated the emergence of thalamic abnormality in relapsing-remitting MS by assessing the thalamic magnetization transfer ratio (MTR) in a cohort with clinically early disease. Twenty-three patients with early relapsing-remitting MS (mean age 37; mean disease duration 1.9 years; Expanded Disability Status Scale (EDSS) range 0-3) and 19 healthy controls (mean age 34) were imaged yearly with a magnetization transfer imaging sequence. Twenty-two MS patients and 14 controls completed two-year follow-up. Regions of interest were placed in both thalami and mean thalamic MTR calculated. At baseline, significant differences between patient and control thalamic MTR were not observed. However, at years one and two, the thalamic MTR in patients was significantly lower than control MTR. Although baseline lesion volume did not correlate with baseline thalamic MTR, at year one, an association between baseline lesion volume and year one thalamic MTR emerged. There was also a significant inverse correlation between EDSS and thalamic MTR (r = -0.47, P = 0.02). The study suggests that thalamic involvement occurs within the first five years of MS onset, when most patients are still minimally disabled.

Adult↗
PubMed2004

Interferon beta-1b in secondary progressive MS: a combined analysis of the two trials.

BACKGROUND: A European (EU) and a North American (NA) placebo-controlled study with interferon beta-1b (IFNB-1b) in secondary progressive multiple sclerosis (SPMS) showed divergent results with regard to their primary outcome of sustained Expanded Disability Status Scale (EDSS) progression, while effects were similar on relapse and MRI-related endpoints. Reasons for this discrepancy were explored in the combined dataset. METHODS: Baseline characteristics and variability in EDSS assessments were compared. Retrospective combined analyses for time to confirmed progression were performed to assess treatment effects overall and in subgroups defined by pre-study disease activity criteria and other key baseline variables. RESULTS: The variance of EDSS measurements was 6.5% higher in the NA-SPMS study. The EU study included patients in an earlier phase of SPMS and with more active disease both pre-study (relapses, MRI) as well as on study (EDSS, relapses, and MRI variables as assessed in the placebo groups). The pooled analysis showed an overall risk reduction by about 20% in patients treated with 8 MIU (250 mcg) IFNB-1b for EDSS progression confirmed at 6 months (p = 0.008). Risk reduction by 30% to 40% was found for patients with at least one relapse or change in EDSS by >1 in the 2 years prior to study entry. No other consistent across-studies relation of clinical and MRI variables at baseline to potential treatment response was found. CONCLUSIONS: Although post hoc, this combined analysis of the two large studies with IFNB-1b in secondary progressive multiple sclerosis suggests that both pronounced disability progression and continuing relapse activity might help in identifying those patients in the secondary progressive phase of the disease who are more likely to benefit from treatment.

Adult↗