MS Abstracts 03a-2g4

Multiple Sclerosis (MS) is a chronic disease of the CNS that most commonly affects young adults.

It is usually characterized in the early years by acute relapses followed by partial or complete remission; in later years progressive and irreversible disability develops.

Because of the protracted and unpredictable clinical course, biological surrogate markers are much needed to make clinical trials of potential disease-modifying treatments more efficient.

Magnetic Resonance (MR) outcome measures are now widely used to monitor treatment outcome in MS trials.

Areas of multifocal inflammation are detected with a high sensitivity as new areas of Gadolinium enhancement and T₂ abnormality, and these may be considered as surrogate markers for clinical relapses.

However, progressive disability is not clearly related to inflammatory lesions but rather to a progressive and diffuse process with increasing NeuroAxonal Loss.

MR surrogate measures for NeuroAxonal Loss include Atrophy (tissue loss in Brain and Spinal Cord), N-AcetylAspartate, and T₁ HypoIntense lesions.

Diffuse abnormality in Normal-Appearing Brain Tissue may also be monitored using Magnetization Transfer Ratio and other quantitative MR measures.

For treatment trials of new agents aimed at preventing disability, measures of NeuroAxonal damage should be acquired.

Especially Atrophy, which occurs at all stages of MS and which can be quantified in a sensitive and reproducible manner.

Because the MR surrogates for NeuroAxonal loss are not yet validated as predicting future disability, definitive trials should continue to monitor an appropriate disability endpoint.

Global Brain Atrophy estimated using MRI and Whole Brain N-AcetylAspartate (WBNAA) concentration measured with Proton MR Spectroscopy were obtained in 42 patients with Relapsing/Remitting Multiple Sclerosis and 41 matched control subjects.

Patients exhibited cross-sectional Atrophy (0.5%; p = 0.033) and WBNAA decline (1.8%/y; p = 0.005) vs disease duration.

The 3.6-fold rate disparity between the two processes suggests that Neuronal/Axonal Dysfunction (N-AcetylAspartate decline) precedes Parenchyma loss, not its consequence (i.e., is an earlier, more sensitive specific metric of the ongoing disease activity).

Multiple Sclerosis is no longer considered to simply be an AutoImmune DeMyelinating Disease. Axonal destruction is another Central pathological feature and a contributor to the accumulating disability of disease progression.

The mechanism underlying Axonal pathology has not been fully clarified but does not appear to be a simple one.

The relationship between Axonal damage and other components of the pathological features such as DeMyelination, Inflammation and ReMyelination are under intense investigation.

Experimental data suggest that therapeutic interventions such as the induction of rapid ReMyelination may lead to the protection of Axons.

In addition to ImmunoModulation, future strategies for NeuroProtection may be of great importance.

Although Voltage-gated Sodium Channels are known to be deployed along experimentally DeMyelinated Axons, the molecular identities of the Sodium Channels expressed along Axons in human DeMyelinating Diseases such as Multiple Sclerosis (MS) have not been determined.

Here we demonstrate changes in the expression of Sodium Channels in DeMyelinated Axons in MS, with Nav1.6 confined to Nodes of Ranvier in controls.

But, with diffuse distribution of Nav1.2 and Nav1.6 along extensive regions of DeMyelinated Axons within acute MS plaques.

Using triple-labeled fluorescent ImmunoCytoChemistry, we also show that Nav1.6, which is known to produce a persistent Sodium Current, and the Na⁺/Ca2⁺ Exchanger.

Which, can be driven by persistent Sodium Current to import damaging levels of Calcium into Axons, are colocalized with ß-Amyloid Precursor Protein, a marker of Axonal injury, in acute MS lesions.

Our results demonstrate the molecular identities of the Sodium Channels expressed along DeMyelinated and degenerating Axons in MS and suggest that coexpression of Nav1.6 and Na⁺/Ca2⁺ exchanger is associated with Axonal degeneration in MS.

Investigations of functional interactions among Axons and Glia over the last decade have revealed the extent and complexity of Glial-Neuronal and Glial-Glial communication during development, adult function and recovery from injury.

These data have profound implications for the understanding of Central Nervous System (CNS) Disorders, which until recently, have been classified as either Neuronal or Glial Diseases.

Re-evaluation of the pathological processes in a number of conditions has clearly shown involvement of both Neurons and Glia in early pathology.

In Multiple Sclerosis (MS), the Myelin sheath has traditionally been regarded as the primary target. However, recent evidence has clearly demonstrated Axonal Damage in new lesions.

We have addressed the question of the role of Axonal pathology in early MS by using well-characterized murine models for the Relapsing/Remitting (RR) or the Primary/Progressive (PP) forms of the disease.

We performed a HistoPathological survey of the CNS, following induction of the disease, to determine the timing of appearance, as well as the development of lesions.

Then we analyzed the relationship between Inflammation, DeMyelination and Axonal damage together with responses from Astrocytes and Microglia in each model from the earliest evidence of inflammation.

We found that Axonal Damage begins well ahead of the appearance of motor symptoms. Pathology appears to be more closely related to the degree of inflammation than to DeMyelination.

We also show that early Astrocyte responses and the degree of Axonal loss are markedly different in the two models and relate to the severity of pathology.

These data support the now widely accepted hypothesis that Axonal Damage begins early in the disease process, but also suggest modulation of Axonal Loss and disease progression by the Astrocytic response.

Multiple Sclerosis (MS) has recently been classified according to its clinical course.

Despite relapses and remissions, its course is invariably progressive, and the observed progression from the Remitting/Relapsing to the Secondary/Progressive form, represents the accumulation of permanent damage to the Nervous System.

Discussions of the nomenclatural position of Schilder's, Marburg's, and Balo's Diseases, ignore the fact that the unique, PathoGnomonic, sharp-edged plaque of MS, is also the pathologic end-result in the three variants.

Devic's Disease or NeuroMyelitis Optica (NMO) is quite different and with some exceptions, is a particular form of Disseminated EncephaloMyelitis (DEM).

There is no evidence that the 'Oriental form of MS' is anything but NMO.

The suggestion that MS and DEM are variants of the same condition is contradicted by the fact that the pathological characteristics of the two are quite different.

While it is probable that the two share aspects of PathoGenesis, the patients differ because of their Genetic endowment.

This was dramatically demonstrated in a group of Japanese patients who died after AntiRabies vaccination and were found to have the typical sharp-edged lesions of MS.

The Genetic determinant was also crucial in the marmoset in which EAE uniquely resulted in a chronic Relapsing/Remitting (RR) disease characterized by the classic sharp-edged lesions of MS.

The question 'ADEM: distinct disease or part of the MS spectrum?' can be answered with a resounding no. A new classification is proposed separating the different forms of MS from the various types of DEM.

Background
This study aimed to investigate if treatment response could retrospectively be related to inflammatory or Axonal pathology as measured by Plasma surrogate markers.

Methods
In this 1-year observational study 30 Multiple Sclerosis (MS) patients with Relapsing/Remitting disease were treated with intramuscular IF-N-ß-1a or subcutaneous IFN-ß-1b.

Responders and nonresponders were defined according to clinical and Magnetic Resonance Imaging criteria. The control group consisted of 14 healthy subjects.

Plasma levels of surrogate markers for inflammation (Nitric Oxide metabolites (NOx)), Astrocytic activation (S100B) and Axonal damage (NfH(SM135)) were measured using standard assays.

Results
There were 11 nonresponders and 19 responders to Interferon-ß treatment.

Median S100B levels were elevated in a higher proportion of treatment responders (63%, 42.9 pg/mL) compared to nonresponders (18%, 11.7 pg/mL, P < 0.05, Fisher's exact test) and controls (0%, 2 pg/mL, P < 0.001).

Levels of NOx were found to be more frequently elevated in nonresponders (72%, 39 microM) compared to healthy controls (0%, 37 microM, P < 0.05).

Levels of NfH(SM135) were more frequently elevated in responders (58%, 300 pg/mL, P < 0.001) and nonresponders (72%, 500 pg/mL, P < 0.001) compared to controls (0%, 4.5 pg/mL).

Conclusion
Patients with Relapsing/Remitting MS who had surrogate marker supported evidence for Astrocytic activation responded more frequently to treatment with IFN-ß.

Cortical functional changes, with the potential to limit the functional consequences of tissue injury, have been shown in patients with Multiple Sclerosis (MS).

In this study, we assessed the influence of MS-related tissue damage of the Brain portion of the Left Pyramidal Tract on the corresponding movement-associated patterns of Cortical recruitment.

We investigated 76 right-handed patients with Definite MS, in a large sample of MS patients when performing a simple motor task with their fully normal functioning right upper limbs.

In each subject, functional Magnetic Resonance Imaging (fMRI) was acquired during the performance of a simple Motor Task with the dominant, right upper limb.

During the same session, dual-echo, Magnetization Transfer (MT) and Diffusion Tensor (DT) MRI sequences were also obtained to quantify the extent and the severity of Pyramidal Tract damage. Lesions along the left Pyramidal Tract were identified in 43 patients.

Compared to patients without Pyramidal Tract lesions, patients with such lesions had more significant activations of the ContraLateral Primary SensoriMotor Cortex (SMC), Secondary SensoriMotor Cortex (SMC2), Inferior Central Sulcus, and Cingulate Motor Area (CMA).

They also showed more significant activations of several regions of the Ipsilateral Hemisphere, including the primary SMC and the Precuneus.

In these patients, T₂ lesion load of left Pyramidal Tract was correlated with the extent of activation of the ContraLateral primary SMC (r2 = 0.25, P < 0.0001).

Whereas no correlations were found between the extent of fMRI activations and the severity of intrinsic lesion damage, as well as with Left Pyramidal Tract Normal-Appearing White Matter Damage.

This study shows that, in patients with MS, following injury of the Motor Pathways, there is an increased recruitment of a widespread SensoriMotor Network, which is likely to contribute to limit the appearance of overt clinical deficits.

The aim of this study was to establish whether, in a cross-sectional study, the normalized measures of Whole and Regional Brain Atrophy correlate better with tests assessing the Cognitive Function than the absolute Brain Atrophy measures.

The NeuroPsychological performances and disability have been assessed in 39 patients with Relapsing/Remitting Multiple Sclerosis (MS).

T₁- and T₂-lesion load (LL) of total Brain and Frontal Lobes (

The Whole Brain Volume and the Regional Brain Parenchymal Volume (RBPV) of FLs were obtained using a computerized interactive program, which incorporates semiautomated and automated segmentation processes.

Normalized measures of Brain Atrophy, i.e., Brain Parenchymal Fraction (BPF) and Regional Brain Parenchymal Fraction (RBPF) of FLs, were calculated.

The scan-rescan, inter- and intrarater Coefficient Of Variation (COV) and Intraclass Correlation Coefficient (ICC) have been estimated.

The RBPF of FLs showed an acceptable level of reproducibility which ranged from 1.7% for intrarater variability to 3.2% for scan-rescan variability.

The mean ICC was 0.88 (CI 0.82-0.93). The RBPF of FLs demonstrated stronger magnitudes of correlation with NeuroPsychological functioning, disability and quantitative MRI lesion measures than RBPV.

These differences were statistically significant: P < 0.001 for Stroop Color Word Interference test, P < 0.001 for Paced Auditory Serial Addition Test, P=0.04 for Standard Raven Progressive Matrices, P=0.049 for Expanded Disability Status Scale, P=0.01 for T₂-LL of FLs and P < 0.001 for T₁-LL of FLs.

BPF demonstrated significant correlations with tests assessing Cognitive functions, whereas BPAV did not.

The correlation analysis results were supported by the results of multiple regression analysis which showed that only the normalized Brain Atrophy measures were associated with tests exploring the Cognitive Functions.

These data suggest that RBPF is a reproducible and sensitive method for measuring Frontal Parenchymal Atrophy.

The normalized measures of whole and Regional Brain Parenchymal Atrophy should be preferred to absolute measures in future studies that correlate NeuroPsychological performances and Brain Atrophy measures in patients with MS.

Objectives
To evaluate the clinical characteristics, course and prognosis of Devic's NeuroMyelitis Optica (DNO), to evaluate the prognostic role of demographic and clinical features, to evaluate the current DNO diagnostic criteria.

Methods
Demographic, clinical, CSF and MRI data of patients affected by DNO were collected from fifteen Italian MS Centres.

Inclusion criteria were:
1. Two or more acute episodes of Neurological dysfunction indicating involvement of the Optic Nerve and Spinal Cord, in a simultaneous or subsequent temporal relationship
2. No evidence of lesions beyond the Optic Nerve or the Spinal Cord
3. Brain MRI at onset negative or non-specific for Multiple Sclerosis (MS) (White Matter lesions < or = 2)
4. Disability was scored by means of Kurtzke's Expanded Disability Status Scale (EDSS)

Results
46 patients with Relapsing DNO were included, 37 females and 9 males, with mean age at onset of 40.1 +/- 16.3 years (range 12-77 years).

The follow up duration was 8.8 +/- 3.5 years, the mean annualized relapse rate was 1.3 +/- 1.2.

After 5, 10 and 15 years EDSS 3.0 was reached respectively by 65%, 82 % and 86% of cases, EDSS 6.0 respectively by 42%, 53 % and 69% of cases, EDSS 10 respectively by 8%, 12% and 23% of cases.

The probability of reaching EDSS 3 was statistically correlated with age at onset, interval between the first and 2 ^nd attack, and relapse rate.

The probability of reaching EDSS 6.0 was correlated with the residual EDSS at onset and to relapse rate. During the follow up, Brain White Matter lesions appeared in 8 subjects.

Spinal Cord MRI showed lesions extending across 3 or more segments in 39 subjects, only 1 lesion involving 1 segment in 4 subjects, and was normal in 3 subjects.

One or more CSF abnormalities were found at least once in 29/44 patients (65.9 %), the most frequent findings being PleoCytosis (38.6 %), OligoClonal Bands (34.1 %), high protein level (25 %), and high Albumin ratio (20.5 %).

Conclusions
DNO has a poor prognosis in most cases. Compared with MS, DNO patients have a higher age at onset, females are more frequently affected, the course is more severe.

Brain and Spinal Cord MRI permit the differentiation of DNO from MS. CSF supports the probability of DNO if it shows increased cells and proteins.

Context
Brain Atrophy is an indicator of Diffuse Brain Pathology that appears even in the early stages of Multiple Sclerosis (MS).

Magnetic Resonance Imaging (MRI) techniques used in clinical trials suggest a correlation between Ventricular enlargement and Axonal pathology and clinical disability in MS.

Objective
To evaluate by TransCranial Sonography (TCS) and MRI Ventricular Diameters in order to assess prospectively the development of Brain Atrophy in MS.

Setting, Patients And Methods
MS outpatient clinic of a University Hospital. 38 MS patients (27 females, 11 males) were followed up for 2 years.

Ventricular Diameters (Third Ventricle, Right and Left Lateral Ventricle) were determined by TCS at baseline, 12 and 24 months.

And correlated with clinical disability (Expanded Disability Status Scale, [EDSS]), and the Multiple Sclerosis Functional Composite Score (MSFC). MRI was performed at study entry and after two years.

Main Outcome Measure
Correlation of Ventricular Diameters measured by TCS and MRI with assessment of clinical disability in MS patients at baseline and after two years.

Results
TCS and MRI measurements especially of Third Ventricle Diameter matched closely at study entry and after two years (r = 0.9; p < 0.0001).

At all time points the width of the Third Ventricle was significantly correlated with clinical disability (EDSS: r = 0.6, p < 0.01; MSFC: r = -0.6, p < 0.02).

In the follow-up over 2 years there was an increase of the width of the Third Ventricle in comparison with study entry (p < 0.002).

Increase of Third Ventricle Width at study entry was associated with higher EDSS levels after 2 years (p = 0.01).

Conclusion
Assessment of Ventricular Diameters by TCS is a reliable tool with which to monitor Brain Atrophy in the longitudinal follow-up of MS patients.

Because TCS is a simple, inexpensive, non-invasive and generally available bedside-test it may be used in clinical practice as well as in therapeutic trials to assess Brain Atrophy.

Background
Cognition and Magnetic Resonance Imaging correlations are well established in patients with Multiple Sclerosis (MS), but it is unclear whether lesion burden or Atrophy accounts for most of the predictive variance. These indices have been directly compared in only a few studies.

No such study included measurement of the Third Ventricle, which was strongly predictive of NeuroPsychological competence in the early literature. Furthermore, few studies accounted for the influence of age, premorbid intelligence, or Depression.

Objective
To determine if conventional measures of lesion burden or Atrophy predict Cognitive Dysfunction in MS while accounting for age, premorbid intelligence, and Depression.

Methods
We studied 37 patients with MS and 27 controls matched according to demographic variables.

Correlations between NeuroPsychological tests and the following Magnetic Resonance Imaging indices were considered: T₁ HypoIntense lesion volume, Fluid Attenuated Inversion Recovery, HyperIntense lesion volume, Third Ventricle Width, BiCaudate Ratio, and Brain Parenchymal Fraction.

Regression models predicting NeuroPsychological performance controlled for the effects of age, premorbid intelligence, and Depression. We included only those tests discriminating patients with MS from controls.

Results
In each regression model, Third Ventricle Width was the sole Magnetic Resonance Imaging measure retained.

When this variable was removed from consideration, Brain Parenchymal Fraction was retained in all analyzes.

Conclusions
Brain Atrophy accounts for more variance than lesion burden in predicting Cognitive Impairment in MS, and Central Atrophy in particular is strongly associated with NeuroPsychological morbidity.

This finding may be explained in part by Atrophy of the Thalamus, a deep Gray Matter structure that mediates Cognitive function via Cortical and SubCortical Pathways.

Enthusiasm for the clinical utility of Third Ventricle Width is tempered by modest intraobserver and interobserver reliability.