Volumetric quantitation by MRI in primary progressive multiple sclerosis: volumes of plaques and atrophy correlated with neurological disability

In primary progressive multiple sclerosis (PPMS) abnormalities in brain magnetic resonance imaging (MRI) differ from abnormalities in other subtypes of multiple sclerosis (MS). It was investigated whether the extent of brain and spinal cord MRI abnormalities is reflected in the neurological disability in PPMS. Focal and diffuse changes and atrophy in central nervous system (CNS) in patients with PPMS (n = 28) and healthy controls (n = 20) were assessed by semi-automatic MRI segmentation and volumetric analysis. The measurements were related to neurological disability as expressed by the expanded disability status scale (EDSS), the regional functional scoring system (RFSS), the arm index and the ambulation index. Plaques in T1- and/or T2-weighted images were seen in all brains, while spinal plaques were detected in 23 of 28 patients (82%). The total volumes of brain and spinal cord were significantly smaller in patients than in controls (P = 0.001 and 0.000, respectively). The volumes of T1 or T2 lesions in the brain correlated to the ambulation index (r = 0.51, P = 0.005 and r = 0.53, P = 0.004, respectively). No correlations were detected between MRI measurements and total EDSS score, but relative brain atrophy correlated inversely with the total RFSS scores, poor arm index and higher cerebral disturbances (r = -0.53, P = 0.004; r = -0.53, P = 0.004; and r = -0.52, P = 0.005, respectively). Although the number of spinal T2 lesions correlated with sensory disturbances (r = 0.60, P = 0.001), no correlations were found between EDSS subscores and spinal cord atrophy. These findings show that marked atrophy of brain and spinal cord detected by volumetric quantitation correlates with neurological disability. This observation indicates the importance of neurodegenerative events in PPMS.     

Serial MRI in multiple sclerosis: a prospective pilot study of lesion load, whole brain volume and thalamic atrophy.

Using serial magnetic resonance imaging (MRI), we investigated the relationship between diffuse cerebral atrophy, T1 and T2 lesion volumes, mean thalamic volumes and clinical progression in patients with established multiple sclerosis (MS). Eleven patients were included in this prospective serial study. Cerebral volumes, T1 hypointense lesion volumes, and T2 hyperintense lesion volumes at baseline and at up to 3 years follow-up were assessed on MRI brain scans. As a putative measure of cerebral atrophy mean thalamic volumes were also obtained. The outcome measures were the MRI parameters and disability on Kurtzke's expanded disability status scale (EDSS). Of the 11 patients 6 worsened clinically as measured by an increase of 0.5 or more on the EDSS. Cerebral atrophy occurred in 91% of patients and was independent of changes in lesion volumes and was not associated with disease progression as determined by the EDSS.     

Adhesion molecules in multiple sclerosis: relation to subtypes of disease and methylprednisolone therapy

OBJECTIVES: To determine levels of adhesion molecules in blood and cerebrospinal fluid (CSF) samples from patients with different subtypes and activities of multiple sclerosis (MS) and to assess the effect of intravenous methylprednisolone sodium succinate treatment on the levels of soluble adhesion molecules. DESIGN: The expressions of very late activation antigen 4 (VLA-4), lymphocyte function associated antigen 1 (LFA-1), vascular cell adhesion molecule 1 (VCAM-1), and intercellular adhesion molecule 1 (ICAM-1) were determined immunocytochemically, and levels of soluble VCAM-1, ICAM-1, and E-selectin, by means of enzyme immunoassay technique. The volumes of T2- and T1-weighted MS plaques and brain atrophy were determined by means of the semiautomatic magnetic resonance imaging (MRI) segmentation technique. SETTING: A university hospital in Finland. PATIENTS: One hundred subjects (71 patients with MS and 29 healthy control subjects). The subtypes of MS were relapsing-remitting (RRMS [n = 26]), secondary progressive (SPMS [n = 20]), and primary progressive (PPMS [n = 25]). RESULTS: In patients with RRMS and SPMS, the expressions of VLA-4 and LFA-1 on immune cells from blood were at least 1.5- to 3-fold higher than in controls (RRMS, P = .002 and P<.001, respectively; SPMS, P = .03 and P =.001, respectively). In RRMS, LFA-1 and ICAM-1 expression in blood was more up-regulated than in SPMS (P = .03 and P = .01, respectively). The expressions of adhesion molecules on CSF lymphocytes in RRMS and SPMS were of similar magnitude, but the proportions of CSF VLA-4- and LFA-1-expressing lymphocytes were 3- to 4-fold higher than in controls (P = .04 and P = .008, respectively). The levels of serum soluble VCAM-1 were higher in SPMS than in RRMS (P = .005) or PPMS (P = .04). Intravenous methylprednisolone treatment of patients with RRMS in exacerbation caused a significant reduction in the serum levels of soluble VCAM-1 and E-selectin (P<.001). In SPMS, the volumes of T2-weighted plaques correlated with the serum level of soluble ICAM-1 (r = 0.64; P = .03). CONCLUSIONS: Up-regulated adhesion molecules in blood and CSF indicate sustained potential for inflammation in the CNS throughout the clinical spectrum of MS. Therapies interfering with cell adhesion may be of key importance in suppressing MS.     

Correlates of MS disability assessed in vivo using aggregates of MR quantities

OBJECTIVES: To assess the magnitude of the correlations between disability and composite MRI scores in patients with MS. METHODS: T2- and T1-weighted MRI, magnetization transfer imaging, diffusion tensor imaging, and MRS imaging scans of the brain from 23 patients with MS were obtained. T2 lesion volume, T1 lesion volume, brain magnetization transfer ratio, average brain diffusivity (D), and brain N-acetylaspartate/creatine ratio were measured. RESULTS: The correlations between the Expanded Disability Status Scale (EDSS) score and each of the MR quantities taken in isolation were not significant, with the exception of the correlation between EDSS and the NAA/creatine ratio (r = -0.50; p = 0.01). In contrast, three of the composite MR scores computed using regression models were strongly correlated with the EDSS scores (r range, 0.58 to 0.73; p range, 0.004 to 0.0001). The model that included T2 and T1 lesion volumes and brain D explained 34% of the EDSS variance; the model that included T2 and T1 lesion volumes and brain N-acetylaspartate/creatine ratio explained 36% of the EDSS variance; the model that included T1 lesion volume, brain D, and brain N-acetylaspartate/creatine ratio explained 53% of the EDSS variance. CONCLUSIONS: The results suggest that multiparametric MR models have the potential to provide powerful measures to monitor MS evolution.     

Cognitive dysfunction in patients with mildly disabling relapsing-remitting multiple sclerosis: an exploratory study with diffusion tensor MR imaging

Neuronal damage seems to be a major source of disability in multiple sclerosis (MS) patients and at present magnetic resonance imaging (MRI) is a sensitive method to evaluate lesion and disease activity. We studied the potential correlation between changes in MS patients' disability after relapse, the degree of T1 lesion hypointensity on MRI in vivo and neuronal apoptosis induced by cerebrospinal fluid (CSF) on neuron cultures. In this study, we included 24 MS patients with relapsing disease. Clinical recovery from relapse was measured by the Expanded Disability Status Scale (EDSS). T1-weighted MRI studies were done according to established standards and neuronal apoptosis was induced by treatment of neuronal cultures with CSF from patients while relapsing. Recovery after relapse is inversely correlated with neuronal apoptosis (r=-0.725, p<0.0001). A correlation was found between T1 lesion hypointensity and a poor recovery from relapse (r=0.656, p=0.0005) and such hypointensity correlated strongly with neuronal apoptosis (r=-0.779, p<0.0001). CSF from all patients with hypointense T1 lesions caused significantly increased neuronal apoptosis, whereas all CSF that did not induced such effects corresponded to patients without T1 lesions. The recovery from an acute MS relapse is significantly worse in patients with hypointense T1 lesions in MRI and in those whose CSF damaged neurons on cultures in vitro, phenomena that closely correlated each other.     

Correlations of brain MRI parameters to disability in multiple sclerosis

OBJECTIVES: The objective was to correlate magnetic resonance imaging (MRI) T2-weighted lesion load and measures of white matter atrophy in the brain to disability in a population-based sample of patients with multiple sclerosis (MS). MATERIAL AND METHODS: A well defined cohort of patients was drawn at random from the general MS population by using the Danish Multiple Sclerosis Registry. A semi-automated local thresholding technique was used to quantify T2-weighted lesions on MRI; whereas manual tracing was applied to measure the corpus callosum brain ratio (CCR) and the ventricle brain ratio (VBR). RESULTS: A sample of 86 patients with a mean age of 43.3 years (SD 4.3), mean disease duration of 13.6 years (SD 4.4) and a median Expanded Disability Status Score (EDSS) of 6.0 was identified. The correlation between total lesion area of the brain (TLA) and disability (EDSS) for the whole sample was moderate (Spearman rank correlation coefficient r=0.48, P<0.001). Also correlations of CCR and VBR to disability (r=0.32-0.46) were significant. CONCLUSIONS: Correlations of TLA and disability in this study were rather strong. Hence, T2-weighted MRI lesion load in the brain still plays an important role as a surrogate marker of disease and as a secondary outcome measure in phase III treatment trials.     

MRI T2 hypointensity of the dentate nucleus is related to ambulatory impairment in multiple sclerosis

OBJECTIVES: MRI T2 hypointensity in multiple sclerosis (MS) gray matter, suggesting iron deposition, is associated with physical disability, disease course, lesion load, and brain atrophy. Ambulatory dysfunction limits quality of life; however correlation with conventional MRI remains poor. METHODS: Normalized intensity on T2-weighted images was obtained in the basal ganglia, thalamus, red nucleus, and dentate nucleus in 47 MS patients and 15 healthy controls. Brain T1-hypointense and FLAIR-hyperintense lesion volume, third ventricle width, brain parenchymal fraction and timed 25 foot walk (T25FW) were measured in the MS group. RESULTS: T2 hypointensity was present throughout gray matter in MS vs. controls (all p<0.01). Dentate T2 hypointensity was the only MRI variable significantly correlated with T25FW (Pearson r=-0.355, p=0.007) and was also the best MRI correlate of physical disability (EDSS) score in regression modeling (r=-0.463, R(2)=0.223, p=0.004). CONCLUSIONS: T2 hypointensity is present in subcortical gray matter nuclei in patients with MS vs. normal controls. Dentate nucleus T2 hypointensity is independently related to ambulatory impairment and disability, accounting for more variance than conventional lesion and atrophy measures. This study adds more weight to the notion that T2 hypointensity is a clinically relevant marker of tissue damage in MS.     

Disability in multiple sclerosis is related to normal appearing brain tissue MTR histogram abnormalities

BACKGROUND: Magnetization transfer ratio (MTR) histogram analysis provides a global measure of disease burden in multiple sclerosis (MS). MTR abnormalities in normal appearing brain tissue (NABT) provide quantitative information on the extent of tissue damage undetected by conventional T2-weighted (T2W) magnetic resonance imaging (MRI). AIMS: 1) To compare the MTR histograms from NABT across a broad spectrum of relapse onset MS patients, including relapsing-remitting (RR) MS (including newly diagnosed and benign subgroups) and secondary progressive (SP) MS. 2) To determine the relationship between clinical disability and NABT MTR histograms. METHODS: 2D spin echo magnetization transfer imaging was performed on 70 RRMS and 25 SPMS patients and compared with 63 controls. MTR histograms were acquired for NABT after extracting lesions and cerebrospinal fluid (CSF). T2W images were used to measure the brain parenchymal fraction (BPF) and T2 lesion load. RESULTS: MS patients had a disease duration ranging from 0.5 to 37 years and an Expanded Disability Status Scale (EDSS) score ranging from 0 to 8.5. There was a significant decrease in NABT mean MTR (+/- standard deviation) compared with controls (33.07 pu +/- 1.06 versus 34.26 pu +/- 0.47; P < 0.001) with an effect size of 2.56. The reduction in NABT mean MTR varied among patient groups from 4.9% for SPMS, 3% for all RRMS, 2.7% for early RRMS and 2.5% for benign MS, compared with controls. NABT mean MTR correlated significantly with T2 lesion load (r = -0.82) and BPF (r = 0.58). EDSS score correlated with NABT mean MTR (r = -0.43), BPF (r = -0.33) and with T2 lesion load (r = 0.59). Multivariate analysis using NABT MTR peak height, T2 lesion load and BPF combined only accounted for 38% of the variance in the EDSS (r = 0.62; P < 0.001). Disease duration accounted for an additional 14% of variance in the EDSS (r = 0.72; P < 0.001). CONCLUSIONS: There is evidence of diffuse abnormalities in NABT in addition to global brain atrophy in relapse onset MS patients, including those with recently diagnosed RRMS and benign MS. The abnormalities are greatest in patients with the more disabling SPMS. Atrophy, NABT and lesion abnormalities are all partly correlated; the processes marked by these MR measures all contribute to disability in MS, providing complementary information relevant to the complex pathological processes that occur in MS.     

多发性硬化、视神经脊髓炎患者血清及脑脊液中脑源性神经营养因子与胶质细胞源性神经营养因子水平

目的 探讨多发性硬化(MS)、视神经脊髓炎(NMO)患者血清及脑脊液中脑源性神经营养因子(BDNF)、胶质细胞源性神经营养因子(GDNF)水平及其神经保护作用.方法 对62例MS、NMO患者及21例对照者进行研究,患者组复发期进行扩展残疾状态量表(EDSS)评分、MRI检查及寡克隆带测定,液相芯片分析技术检测血清及脑脊液BDNF、GDNF浓度.结果 MS、NMO患者复发期血清及脑脊液BDNF(μg/L,MS患者:5.616±0.650、0.186±0.012;NMO患者6.584±0.929、0.176±0.006)、GDNF浓度(μg/L,MS患者:0.039、0.080;NMO患者0.029、0.050)与对照组(μg/L,血清:4.374±0.501、0.040;脑脊液:0.152±0.011、0.065)比较差异无统计学意义;脑脊液BDNF与GDNF浓度水平呈正相关(r=0.756,P=0.000),血清BDNF与GDNF浓度水平呈负相关(r=-0.329,P=0.018).血清及脑脊液BDNF、GDNF浓度与EDSS评分、血脑屏障指数、Delpech指数及Tourtellotte合成率无明显相关性.有或无脑萎缩的MS、NMO患者血清及腩脊液BDNF、GDNF浓度差异无统计学意义.结论 MS、NMO患者体内BDNF与GDNF水平相关,二者可能具有协同的神经保护作用.BDNF及GDNF与NMO、MS患者血脑屏障破坏及中枢神经系统内IgG合成无关,与神经功能残疾及脑萎缩的关系仍需研究.     

Quality of life and its relationship to brain lesions and atrophy on magnetic resonance images in 60 patients with multiple sclerosis

CONTEXT: Disease-modifying multiple sclerosis (MS) therapeutic trials continue to rely on physical disability as the main clinical outcome measure, while the impact of treatment on quality of life (QOL) is poorly understood. Weak correlations exist between physical disability and the disease burden as shown using conventional brain magnetic resonance imaging (MRI), indicating poor sensitivities of these measures alone in defining the clinical course of MS. OBJECTIVES: To investigate the impact of MS on QOL; to determine whether impaired QOL in patients with MS was related to any regional brain abnormalities assessed using conventional MRI sequences; and to determine if the severity of MS as assessed by the Expanded Disability Status Scale (EDSS) and clinical course was associated with worsening QOL. DESIGN, SETTING, AND PATIENTS: Prospective, cross-sectional study of 60 consecutive patients with MS treated in a community-based, university-affiliated MS clinic. MAIN OUTCOME MEASURES: Assessments of QOL using the Multiple Sclerosis Quality of Life-54 Instrument were correlated with the scores of the EDSS, clinical course, and findings on brain MRI. RESULTS: Quality of life was significantly impaired in patients with MS and was worse in patients with secondary-progressive MS compared with those with relapsing-remitting MS. Brain MRI lesions and atrophy were associated with impaired QOL with respect to sexual dysfunction, overall mental health, and limitations due to physical and emotional dysfunction. Correlations between MRI results and QOL assessments were much stronger for hypointense lesions and atrophy on T1-weighted images than for hyperintense lesions on T2-weighted images and were insignificant for lesions on contrast-enhanced images. Higher EDSS scores were associated with impairments in most physical and mental health QOL scales but were weakly correlated with cognitive and sexual dysfunction. CONCLUSIONS: In patients with MS, QOL is impaired and is associated with increasing neurologic disability. Quality of life assessments are related in part to brain lesions and atrophy shown on MRI. Assessments of QOL provide unique information not readily evaluated by EDSS and may be useful as secondary clinical outcome measures. Arch Neurol. 2000;57:1485-1491     

Magnetic resonance imaging measures of brain and spinal cord atrophy correlate with clinical impairment in secondary progressive multiple sclerosis

BackgroundNeuroaxonal loss is a pathological substrate of disability in progressive multiple sclerosis (MS) and can be estimated in vivo by measuring tissue atrophy on magnetic resonance imaging (MRI). While there is some evidence that brain atrophy correlates better with disability than T2 lesion load in secondary progressive MS, the clinical relevance of atrophy within specific regions of the central nervous system requires further evaluation.MethodsClinical and MRI examinations were performed in 117 subjects with secondary progressive MS. MRI analysis included measures of normalized brain volume (NBV), normalized grey matter (NGMV) and white matter volume (NWMV), central cerebral volume (CCV), spinal cord cross-sectional area (SCCA), and brain T2 and T1 lesion volume. Clinical assessments included the expanded disability status scale (EDSS) and MS functional composite (MSFC).ResultsAll MRI measures correlated significantly with the MSFC score, with the strongest correlation being for the NBV (r = 0.47; P < 0.001). NBV and SCCA were the only significant independent predictors of the MSFC score in a stepwise regression model containing all the MRI measures, and SCCA was the only MRI measure to show a significant association with the EDSS. While NGMV had stronger correlations with the clinical variables than NWMV, NBV was more correlated with clinical impairment than either measure.ConclusionsThis data suggests that measures of atrophy, particularly of the whole brain and spinal cord, are relevant and useful disease markers in secondary progressive MS.     

Regional Brain Atrophy Is Associated With Physical Disability in Multiple Sclerosis: Semiquantitative Magnetic Resonance Imaging and Relationship to Clinical Findings

OBJECTIVE: Brain atrophy may occur early in the course of multiple sclerosis (MS) and may be associated with disability. Brain magnetic resonance imaging (MRI) of 114 MS patients (group A) were analyzed for regional atrophy (vs age-/gender-matched controls) and T1 and T2 lesions using 4-point rating systems. Thirty-five separate patients (group B) were analyzed for cortical atrophy (ordinal scale), third ventricular width, and total T2 hyperintense lesion volume (computer assisted). In group A, regression modeling indicated that inferior frontal atrophy (P = .0003) and T2 lesions in the pons (P = .02) predicted physical disability (Expanded Disability Status Scale [EDSS] score). Secondary progressive (SP) versus relapsing patients were predicted by inferior parietal (P = .002), superior parietal (P = .006), temporal (P = .008), inferior frontal (P = .01), superior frontal (P = .01), cerebellum (P = .01), occipital (P = .01), and midbrain (P = .02) atrophy. SP patients were also predicted by total atrophy (P = .01) and third ventricular enlargement (P = .03) but not T1 or T2 lesions. In group B, the regression model predicting EDSS score included only superior frontal atrophy (r = 0.515, P = .002). Mean kappa coefficients of ordinal ratings were 0.9 (intraobserver) and 0.8 (interobserver). Ordinal ratings correlated well with quantitative assessments. The authors conclude that brain atrophy is closely associated with physical disability and clinical course in MS patients and can be appreciated using a semiquantitative MRI regional rating system.     

多发性硬化、临床孤立综合征患者脑脊液β-淀粉样肽水平及其意义研究

目的 探讨多发性硬化(MS)及其早期表现-临床孤立综合征(CIS)患者脑脊液β-淀粉样肽(Aβ42)表达水平及其与病程、神经功能缺失以及MRI T2高信号病灶数量的关系.方法 对33例MS患者、23例CIS患者及13例对照者进行研究,MS、CIS患者发作期进行扩展残疾状态量表(EDSS)评分及MRI检查,采用液相芯片分析技术检测各组患者脑脊液Aβ42浓度.结果 MS、CIS患者发作期脑脊液Aβ42浓度与对照组相比差异无统计学意义(P>0.05),但继发进展型MS(SPMS)患者脑脊液Aβ42浓度[(167.99±36.39)pg/mL]比复发缓解型MS(RRMS)患者[(92.74±13.64)pg/mL]高,差异有统计学意义(P=0.042).MS、CIS患者脑脊液Aβ42浓度与病程及EDSS评分无明显相关性(P>0.05).病程≥1年的MS患者脑脊液Aβ42浓度比病程<1年的患者低,EDSS评分≥4.5分的MS、CIS患者脑脊液Aβ42浓度比EDSS评分<4.5分的患者低,但差异均无统计学意义(P>0.05).MS、CIS患者脑脊液Aβ42浓度与MRI T2高信号病灶数量呈正相关关系(MS患者:r=0.507.P=0.038;CIS患者:r=0.485,P=0.049).MRI T2高信号病灶总数≥4个的MS患者脑脊液Aβ42浓度[(129.34±19.96)pg/mL]比病灶总数<4个的MS患者[(73.51±12.60)pg/mL]高,差异有统计学意义(P=0.049).结论 SPMS患者轴突损伤比RRMS患者严重;脑脊液Aβ42水平升高可能是MS病情进展的标记之一;MRI T2高信号病灶负荷可能与MS轴突损伤有关.     

Urodynamic findings in primary progressive multiple sclerosis are associated with increased volumes of plaques and atrophy in the central nervous system

OBJECTIVE: Voiding dysfunction is more frequent in primary progressive multiple sclerosis (PPMS) than in other subtypes of MS. We investigated whether lower urinary tract disorders are reflected in the extent of changes in brain and spinal cord detected by magnetic resonance imaging (MRI). METHODS: Micturition symptoms and specific urodynamic findings in 24 patients with PPMS were related to MRI abnormalities as analysed by segmentation and volumetric analysis. RESULTS: Urgency and urge incontinence were the most frequent urinary symptoms (83 and 75 %), while detrusor sphincter dyssynergia (DSD) (71%), detrusor hyperreflexia (58%) and obstruction (58%) were the most common micturition dysfunctions. Comparison between patients with detrusor hyperreflexia and those with normal bladder function revealed higher volumes of T2-weighted plaques in the brains of former (P = 0.01). In patients with hypotonic bladder the total brain volume was smaller (P = 0.02) and the number of thoracic plaques in T2-weighted images higher (P = 0.02) compared to patients with normal bladder function. Furthermore, DSD was associated with a higher volume of T2-weighted plaques in the brain (P = 0.02). CONCLUSIONS: Voiding dysfunction in PPMS is associated with increasing brain and spinal cord abnormalities. Urodynamic investigation is, however, needed for specific definition of micturition disturbances and should be made before therapeutic decisions.     

Increased disability and MRI lesions after discontinuation of IFN-beta-1a in secondary progressive MS

OBJECTIVE: To examine neurological and magnetic resonance imaging (MRI) changes following discontinuation of interferon (IFN)-beta-1a treatment in secondary progressive multiple sclerosis (SPMS). METHODS: The study involved 21 SPMS patients who received subcutaneous (s.c.) IFN-beta-1a 44 microg three times weekly (t.i.w.) for 12 months and were thereafter followed up without treatment for a further 12 months. The number of relapses, disability on the Expanded Disability Status Scale (EDSS) and MRI were recorded at baseline, at 12 months of IFN-beta-1a 44 microg t.i.w. and 1 year after discontinuation of treatment. RESULTS: During the 12-month treatment EDSS score and volumes of brain T2- and T1-weighted lesions remained without significant progression, but at 12 months after treatment discontinuation both EDSS score and the volumes of cerebral lesions increased significantly. Cerebrospinal fluid fraction increased significantly both during the treatment and during follow-up. CONCLUSIONS: Discontinuation of IFN-beta-1a 44 microg t.i.w. in SPMS may be associated with an increase in neurological disability and brain lesions on MRI.     

Grey matter magnetization transfer ratio independently correlates with neurological deficit in secondary progressive multiple sclerosis

Although there is substantial brain grey matter pathology in secondary progressive multiple sclerosis (MS), there has been limited investigation of its contribution to disability. This study investigated the correlation of magnetization transfer ratio (MTR) measures taken from brain grey matter, normal appearing white matter (NAWM) and lesions with neurological deficit and disability in 113 people with secondary progressive MS. In order to adjust for the potential effects of focal white matter lesions and global brain atrophy, T2 lesion volume and normalized brain volume (NBV) were also calculated for each subject. Clinical measures included the expanded disability status scale (EDSS) and the multiple sclerosis functional composite (MSFC) scores. Linear regression analysis was used to assess the age- and gender-adjusted correlation of MTR histogram mean, peak height and peak location with the MSFC and individual component measures. Logistic regression analysis was used to determine whether imaging measures could be used to predict if subjects were in the higher disability group (EDSS ≥ 6.5). Significant correlations were detected between MSFC composite and mean MTR in (i) normal appearing white matter (NAWM; r = 0.327, p < 0.0001), (ii) grey matter (r = 0.460, p < 0.0001) and (iii) lesions (r = 0.394, p < 0.0001). Although NBV and T2 lesion volume correlated significantly with MSFC, grey matter histogram mean emerged as the best predictor of MSFC score. None of the MRI measures significantly predicted higher EDSS. These results suggest that brain grey matter pathology plays an important role in determining neurological impairment. The apparent paucity of correlation between MRI measures and EDSS is likely to represent the relative insensitivity of the latter measure in this study group.     

N-acetylaspartic acid in cerebrospinal fluid of multiple sclerosis patients determined by gas-chromatography-mass spectrometry

Abstract Background Axonal degeneration is considered to play a major role in the development of clinical disability in multiple sclerosis (MS). N-AcetylAspartic Acid (NAA) is a neuron-specific marker constantly identified in MR-spectroscopy studies of the normal and MS brain. To our knowledge there are no studies available that evaluated NAA in cerebrospinal fluid (CSF) as a possible marker for disease severity. Objective To evaluate CSF concentrations of NAA in MS in relation to disease phenotype, clinical measures of disability and MRI markers of disease burden. Methods NAA concentrations were determined in CSF of 46 patients with MS (26 relapsing remitting (RRMS), 12 secondary progressive (SPMS) and 8 primary progressive (PPMS)). Prior to lumbar puncture, MS-patients underwent MRI and clinical examination, including the Expanded Disability Status Scale (EDSS) and the MS Functional Composite (MSFC). Additionally, CSF concentrations of NAA were determined in 12 patients with other neurological diseases (OND). Results Median CSF NAA concentration was 0.74 (IQR: 0.59–0.94) in RRMS , 0.54 (IQR: 0.35–0.73) in SPMS and 0.83 μmol/l (IQR: 0.56–1.03) in PPMS patients. SPMS patients had a significantly lower NAA concentration than RRMS patients. NAA concentrations correlated with EDSS (r = )0.37, p = 0.016), MSFC (r = 0.41, p = 0.010), normalised brain volume (r = 0.49, p = 0.001), T2 lesion load (r = )0.35, p = 0.021) and black hole lesion load (r = )0.47, p = 0.002). No differences were observed between OND (median: 0.57 IQR: 0.28–0.73) and MS patients. Conclusion CSF NAA concentration in MS patients is related to clinical performance and MRI measures of disease burden and may therefore be an important neuron specific marker of disease severity and possibly progression.     

脑多发性硬化病灶和脑萎缩的MRI特点及其相关因素的研究

目的 探讨脑多发性硬化(MS)病灶和脑萎缩的MRI特点,并对其与脑萎缩的关系及其相关因素进行分析.方法 80例确诊的脑MS患者按照年龄分成两组;每例患者MRI检查时均进行5 mm层厚不间断横断面T1、T2加权像扫描;观察MS的病灶数目、信号和形态特点及分布规律;测量脑萎缩数据,并与正常对照组进行比较;对MS脑萎缩的相关因素进行分析.结果 (1)MRI显示脑MS病灶多呈卵圆形或类圆形,边界较清楚,典型病灶长轴与侧脑室切线垂直,病灶以等或稍长T1、长T2信号改变为主.(2)与健康对照组比较,脑MS患者脑室的测量径线明显增大,脑沟及外侧裂明显增宽,脑实质的测量径线明显缩小.(3)对MS患者脑萎缩的相关因素进行分析得出扩展残疾状态评分(EDSS)是脑萎缩的最主要预测因素.结论 脑MS的病灶多分布在侧脑室周围,以等或稍长T1、长T2信号为主,病灶形态多呈卵圆形或类圆形,边界较清楚;脑MS患者的病程、病灶的数目及直径以及EDSS得分均与脑萎缩明显相关;脑萎缩在脑MS患者中普遍存在并逐渐进展,其测量数据可作为临床监测MS进展的一个有用指标.     

Automated segmentation of multispectral brain MR images

This work presents a robust and comprehensive approach for the in vivo automated segmentation and quantitative tissue volume measurement of normal brain composition from multispectral magnetic resonance imaging (MRI) data. Statistical pattern recognition methods based on a finite mixture model are used to partition the intracranial volume into gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) spaces. A masking algorithm initially extracts the brain volume from surrounding extrameningeal tissue. Radio frequency (RF) field inhomogeneity effects in the images are then removed using a recursive method that adapts to the intrinsic local tissue contrast. Our technique supports heterogeneous data with multispectral MR images of different contrast and intensity weighting acquired at varying spatial resolution and orientation. The proposed image segmentation methods have been tested using multispectral T1-, proton density-, and T2-weighted MRI data from young and aged non-human primates as well as from human subjects.     

A 6-year clinical and MRI follow-up study of patients with relapsing–remitting multiple sclerosis treated with Interferon-beta

There are few long-term clinical and magnetic resonance imaging (MRI) data on patients treated with interferon-beta (IFN-beta) for relapsing-remitting multiple sclerosis (RRMS). The aim of this study was to provide clinical and MRI data on 68 patients with RRMS treated over a 6-year period and to investigate whether a baseline MRI predicts their long-term clinical and MRI outcome. Six MRI scans were performed monthly before treatment and a further 13 scans were performed during treatment with IFN-beta, the last of which 6 years after commencement of treatment. The relapse rate, disability as measured by the Expanded Disability Status Scale (EDSS), and MRI parameters, including Gd-enhancing lesion load (Gd-LL), T2 hyperintense lesion load (T2-LL) T1 hypointense lesion load (T1-LL) and supratentorial brain volume (SBV) were measured throughout the study. The mean annual relapse rate over the 6 years was 0.52 (SD 0.67), which is significantly lower (68.6%) than the mean annual relapse rate of 1.6 observed during the 2-year period before the commencement of treatment (P < 0.01). The median EDSS score increased from 2 to 2.5, remaining stable in 60% of the patients. From the baseline scan to the final scan, there was a median increase of 7% in the T2-LL and 23.9% in the T1-LL, whilst SBV decreased by 2.7%. The increase in the EDSS over the course of the study was significantly correlated with a reduction in brain volume (r = 0.46, P = 0.001). Greater brain damage at baseline, as measured by both T2-LL and T1-LL, was significantly associated with an increase in disability over the 6 years (r = 0.44, P = 0.0009; r = 0.50, P = 0.0007, respectively). This study shows a sustained effect of IFN-beta on the relapse rate, which is lower than during the 2 years before treatment commencement. More than half the patients showed an improvement or stabilization in the EDSS score. The increment in disability was correlated with the development of brain atrophy but not with increases in lesion burden. Finally, the finding that the extent of lesion burden at the baseline was a strong predictor of increasing disability suggests that IFN-beta treatment might have a moderate effect in modifying the multiple sclerosis (MS) disease course over 6 years unless preventive treatment is started early.