The association between retinal nerve fibre layer thickness and N-acetyl aspartate levels in multiple sclerosis brain normal-appearing white matter: a longitudinal study using magnetic resonance spectroscopy and optical coherence tomography.

BACKGROUND AND PURPOSE: N-acetyl aspartate (NAA) assessed using proton magnetic resonance spectroscopy (1 H MRS) has a high pathological specificity for axonal density. Retinal nerve fibre layer thickness (RNFLT) measured by using optical coherence tomography is increasingly used as a surrogate marker of neurodegeneration in multiple sclerosis (MS). Our aim was to investigate the relation between RNFLT and NAA/creatine in brain normal-appearing white matter (NAWM), their dynamics over time and the association with clinical outcome measures in relapsing MS. T2 WM lesions served as control tissue. METHODS: Forty-three MS patients underwent standardized neurological examination including the Expanded Disability Status Scale (EDSS), Multiple Sclerosis Functional Composite (MSFC) score, optical coherence tomography and magnetic resonance imaging including 1 H MRS at baseline and after 1 year. RESULTS: At baseline, NAA/creatine level was lower in T2 WM lesions than in NAWM (1.64 ± 0.16 vs. 1.88 ± 0.24, P < 0.001). Lowest levels were found in secondary progressive MS (SPMS). Mean RNFLT was higher in clinically isolated syndrome than in the combined group of relapsing-remitting MS and SPMS (99.8 ± 12.3 µm vs. 92.4 ± 12.8 µm, P = 0.038). In all patients, mean RNFLT decreased by 1.4% during follow-up. At baseline, MSFC z-scores correlated with NAA/creatine levels both in NAWM (r = 0.42; P = 0.008) and T2 WM lesions (r = 0.52, P = 0.004). NAWM NAA/creatine variation correlated with the RNFLT change over 1 year (ρ = 0.43, P = 0.046). CONCLUSIONS: N-acetyl aspartate/creatine level reduction correlated with RNFLT thinning over 1 year in an EDSS stable MS cohort suggesting that these techniques might be sensitive to detect subclinical disease progression.

Peripheral nervous system involvement in multiple sclerosis.

OBJECTIVE: To investigate possible peripheral nervous system (PNS) affection in patients with multiple sclerosis (MS) by standard nerve conduction velocity (SNC) and pain-related evoked potentials (PREP), a novel electrophysiological method for diagnosing small fibre neuropathy. BACKGROUND: Former neuropathological and electrophysiological studies demonstrated subtle PNS affection in MS, but routine measurements are mostly normal. Small fibre polyneuropathy is associated with several autoimmune diseases but has not been investigated in MS yet. DESIGN/METHODS: Fifty-four patients with MS (43 relapsing-remitting, 11 secondary progressive MS) underwent SNC of the tibial, sural and peroneal nerve. Twenty-one patients additionally underwent PREP. RESULTS: SNC abnormalities were observed in 29.6% of all patients and 14.2% of all nerves examined No abnormalities on PREP were found. CONCLUSIONS/RELEVANCE: We demonstrated subtle alterations on routine electrophysiological measurements in patients with MS without hints for small fibre pathology.

Efficacy of natalizumab in second line therapy of relapsing-remitting multiple sclerosis: results from a multi-center study in German speaking countries.

BACKGROUND: Natalizumab has been recommended for the treatment of relapsing-remitting multiple sclerosis (RRMS) in patients with insufficient response to interferon-beta/glatiramer acetate (DMT) or aggressive MS. The pivotal trials were not conducted to investigate natalizumab monotherapy in this patient population. METHOD: Retrospective, multicenter study in Germany and Switzerland. Five major MS centers reported all RRMS patients who initiated natalizumab >or=12 months prior to study conduction. RESULTS: Ninety-seven RRMS patients were included [69% female, mean age 36.5 years, mean Expanded Disability Status Scale (EDSS) 3.4; 93.8% were pre-treated with DMT], mean treatment duration with natalizumab was 19.3 +/- 6.1 months. We found a reduction of the annualized relapse rate from 2.3 to 0.2, 80.4% were relapse free with natalizumab. EDSS improved in 12.4% and 89.7% were progression free (change of >or= 1 EDSS point). Eighty-six per cent of patients with highly active disease (>or= 2 relapses in the year and >or= 1 Gadolinium (Gd)+ lesion at study entry, n = 20) remained relapse free. The mean number of Gd enhancing lesions was reduced to 0.1 (0.8 at baseline). Discontinuation rate was 8.2% (4.1% for antibody-positivity). CONCLUSION: Natalizumab is effective after insufficient response to other DMT and also in patients with high disease activity.

Quality of life in 1000 patients with early relapsing-remitting multiple sclerosis.

BACKGROUND AND PURPOSE: To examine the quality of life (QoL) in a large cohort of untreated patients with relapsing-remitting multiple sclerosis (RRMS) and to investigate the impact of intramuscular (IM) interferon beta-1a (IFNbeta-1a) treatment. METHODS: Prospective, observational, open-label, multicentre study conducted in Germany. Untreated patients with RRMS who initiated treatment with IM IFNbeta-1a were included and followed for 12 months. QoL was measured using the EQ-5D questionnaire. Clinical response was assessed by relapse rate and disability (Expanded Disability Status Scale; EDSS). RESULTS: A total of 1157 patients were included [mean age 37.6 years, median disease duration 13 months, mean relapse rate 1.7 (95%CI: 1.58-1.73), median EDSS score 2.0]. Relapse rate was reduced to 0.6 at 12 months (95%CI: 0.51-0.69, P < 0.0001). EDSS did not change significantly. At baseline, QoL was considerably lower in MS patients compared with the general German population, but was improved after treatment initiation [utilities of EQ-5D: 0.77 (95%CI: 0.75-0.78) vs. 0.75 (95%CI: 0.74-0.76) at baseline, 95%CI for difference: 0.01-0.03, P = 0.0046]. Higher disease activity and inability to work were negative predictors of QoL. 14.7% of patients were incapable of working for MS-related reasons. CONCLUSIONS: Quality of life is considerably impaired in early stages of MS. Treatment initiation with IM IFNbeta attenuates MS disease activity and improves QoL. Inability to work early during the disease is a major challenge for the social security systems.

Natalizumab is effective as second line therapy in the treatment of relapsing remitting multiple sclerosis.

BACKGROUND: Natalizumab has been recommended for the treatment of patients with relapsing remitting multiple sclerosis with insufficient response to interferon-beta (IFN-beta) or glatiramer acetate (GA). METHOD: Prospective, observational study. RESULTS: We found a reduction of the annualized relapse rate from 2.1 under IFN-beta or GA to 0.2 one year after switching to natalizumab. There were 94% fewer gadolinium enhancing lesions with natalizumab. CONCLUSION: Natalizumab reduced short term clinical and MRI activity in second line therapy and efficacy is comparable to first line therapy as demonstrated in the pivotal trials.

Prevalence of migraine, tension-type headache and trigeminal neuralgia in multiple sclerosis.

BACKGROUND: Prevalence rates of headache in multiple sclerosis (MS) patients varied widely in recent studies. This study aimed to investigate the 1 year prevalence of headache in MS compared with the general population. METHODS: Population-based case-control study in Germany. RESULTS: We included 491 patients with definite MS (68% female, mean age 45.3 years, 63.7% relapsing remitting MS, mean Expanded Disability Status Scale (EDSS) 3.2, 106 treated with interferon-beta, 53 with glatiramer acetate, 271 untreated) and 447 age and gender matched controls. Headache was diagnosed with a validated questionnaire according to the International Headache Society Criteria. Headache prevalence was 56.2% (tension type headache 37.2%, migraine 24.6%). Headache prevalence rates did not differ from controls. Headache was not associated with disability or treatment. Trigeminal neuralgia was found in 6.3% of MS cases. CONCLUSION: Results suggest that headache in MS patients reflects comorbidity in most conditions.

First clinical study on ultra-high-field MR imaging in patients with multiple sclerosis: comparison of 1.5T and 7T.

BACKGROUND AND PURPOSE: Higher magnetic field strengths and continuous improvement of high-resolution imaging in multiple sclerosis (MS) are expected to provide unique in-vivo and non-invasive insights in pathogenesis and clinical monitoring. The purpose of this study was to investigate the potential of high-resolution imaging of MS lesions in vivo comparing 7T with conventional 1.5T. MATERIALS AND METHODS: Twelve consecutive patients with clinically definite MS were scanned on a 7T whole-body scanner and on a 1.5T Avanto. The 1.5T and 7T imaging protocol consisted of high-resolution axial proton density (PD) + T2-weighted turbo spin-echo and T2*-weighted gradient-echo (GRE), and sagittal T1-weighted 3D magnetization-prepared rapid acquisition of gradient echo. RESULTS: The sequence parameters at 7T had to be modified because of specific absorption rate (SAR) restrictions while keeping contrast parameters equivalent to 1.5T. White matter lesions were better detected and delineated from adjacent structures at 7T compared with 1.5T. There were 42% of the patients who showed additional lesions at 7T: there were 97 white matter lesions detected on 1.5T versus 126 lesions at 7T, an increase of 23%. The perivascular migration of MS lesions was well visualized on T2*-weighted GRE sequences. In larger lesions (10 mm), a multilayer structure was revealed on T2*-weighted GRE not seen at 1.5T. Because of the higher resolution, it was possible to differentiate between juxtacortical white matter lesions and cortical lesions. There were 44% of the subcortical lesions depicted at 7T that showed cortical involvement. CONCLUSIONS: Ultra-high-field imaging of patients with MS at 7T was well tolerated and provided better visualization of MS lesions in the gray matter and demonstrated structural abnormalities within the MS lesions themselves more effectively.

Increased basal-ganglia activation performing a non-dystonia-related task in focal dystonia.

BACKGROUND AND PURPOSE: We tried to determine whether altered sensorimotor cortex and basal-ganglia activation in blepharospasm (BSP) and cervical dystonia (CD) are restricted to areas directly responsible for the innervation of dystonic muscles, or whether impairment in focal dystonia reaches beyond these direct associations supporting a more global disturbance of sensory and motor control in focal dystonia. METHODS: Twenty patients with focal dystonia (11 BSP, 9 CD) and 14 healthy controls were investigated with functional magnetic resonance imaging (fMRI) performing a simple grip force forearm contraction task. RESULTS: BSP and CD patients and healthy controls showed similar activation in the pre-motor, primary motor and primary sensory cortex, whilst basal-ganglia activation was increased in BSP and CD with related activation patterns compared with controls. BSP patients had increased activation in the thalamus, caudate nucleus, putamen and lateral globus pallidus, whilst CD patients showed increased activation in the caudate nucleus, putamen and thalamus. No differences in applied grip force were detected between groups. CONCLUSIONS: In both, BSP and CD, increased basal-ganglia activation could be demonstrated in a task not primarily involving the dystonic musculature affected by these disorders. Comparable activation changes may also indicate a common pathway in the pathophysiology in BSP and CD.

Nociceptive-specific blink reflex and glyceryl trinitrate infusion in healthy volunteers.

Glyceryl trinitrate (GTN) is known to induce early headache in healthy humans after intravenous infusion. Moreover, in animal models subcutaneous administration produces an increase in Fos expression in brainstem areas that are involved in trigeminal pain processing. In a double-blind crossover study, we tested the blink reflex before, during and immediately after GTN and placebo intravenous infusion in eight healthy volunteers using a new stimulation electrode that preferentially activates A-delta nociceptive afferent fibres. The initial hypothesis that GTN could induce an increase in the magnitude of the nociceptive blink reflex R2 component by stimulating activity of trigeminal nucleus caudalis wide dynamic range interneurones was not confirmed. Although mild headache was induced in six subjects, there was no significant change between the R2 area under the curve before and after drug vs. placebo.