Synaptic injury in the inner plexiform layer of the retina is associated with progression in multiple sclerosis

While neurodegeneration underlies the pathological basis for permanent disability in multiple sclerosis (MS), predictive biomarkers for progression are lacking. Using an animal model of chronic MS, we find that synaptic injury precedes neuronal loss and identify thinning of the inner plexiform layer (IPL) as an early feature of inflammatory demyelination-prior to symptom onset. As neuronal domains are anatomically segregated in the retina and can be monitored longitudinally, we hypothesize that thinning of the IPL could represent a biomarker for progression in MS. Leveraging our dataset with over 800 participants enrolled for more than 12 years, we find that IPL atrophy directly precedes progression and propose that synaptic loss is predictive of functional decline. Using a blood proteome-wide analysis, we demonstrate a strong correlation between demyelination, glial activation, and synapse loss independent of neuroaxonal injury. In summary, monitoring synaptic injury is a biologically relevant approach that reflects a potential driver of progression.

A real-world clinical validation for AI-based MRI monitoring in multiple sclerosis

Modern management of MS targets No Evidence of Disease Activity (NEDA): no clinical relapses, no magnetic resonance imaging (MRI) disease activity and no disability worsening. While MRI is the principal tool available to neurologists for monitoring clinically silent MS disease activity and, where appropriate, escalating treatment, standard radiology reports are qualitative and may be insensitive to the development of new or enlarging lesions. Existing quantitative neuroimaging tools lack adequate clinical validation. In 397 multi-center MRI scan pairs acquired in routine practice, we demonstrate superior case-level sensitivity of a clinically integrated AI-based tool over standard radiology reports (93.3% vs 58.3%), relative to a consensus ground truth, with minimal loss of specificity. We also demonstrate equivalence of the AI-tool with a core clinical trial imaging lab for lesion activity and quantitative brain volumetric measures, including percentage brain volume loss (PBVC), an accepted biomarker of neurodegeneration in MS (mean PBVC -0.32% vs -0.36%, respectively), whereas even severe atrophy (>0.8% loss) was not appreciated in radiology reports. Finally, the AI-tool additionally embeds a clinically meaningful, experiential comparator that returns a relevant MS patient centile for lesion burden, revealing, in our cohort, inconsistencies in qualitative descriptors used in radiology reports. AI-based image quantitation enhances the accuracy of, and value-adds to, qualitative radiology reporting. Scaled deployment of these tools will open a path to precision management for patients with MS.

Cervical spinal cord atrophy in amyotrophic lateral sclerosis across disease stages

OBJECTIVE

Spinal cord degeneration is a hallmark of amyotrophic lateral sclerosis. The assessment of gray matter and white matter cervical spinal cord atrophy across clinical stages defined using the King's staging system could advance the understanding of amyotrophic lateral sclerosis progression.

METHODS

We assessed the in vivo spatial pattern of gray and white matter atrophy along cervical spinal cord (C2 to C6 segments) using 2D phase-sensitive inversion recovery imaging in a cohort of 44 amyotrophic lateral sclerosis patients, evaluating its change across the King's stages and the correlation with disability scored by the amyotrophic lateral sclerosis functional rating scale revised (ALSFRS-R) and disease duration. A mathematical model inferring the potential onset of cervical gray matter atrophy was developed.

RESULTS

In amyotrophic lateral sclerosis patients at King's stage 1, significant cervical spinal cord alterations were mainly identified in gray matter, whereas they involved both gray and white matter in patients at King's stage ≥ 2. Gray and white matter areas correlated with clinical disability at all cervical segments. C3-C4 level was the segment showing early gray matter atrophy starting about 7 to 20 months before symptom onset according to our model.

INTERPRETATION

Our findings suggest that cervical spinal cord atrophy spreads from gray to white matter across King's stages in amyotrophic lateral sclerosis, making spinal cord magnetic resonance imaging an in vivo assessment tool to measure the progression of the disease.

Spinal cord atrophy predicts progressive disease in relapsing multiple sclerosis

Objective

A major challenge in multiple sclerosis (MS) research is the understanding of silent progression and Progressive MS. Using a novel method to accurately capture upper cervical cord area from legacy brain MRI scans we aimed to study the role of spinal cord and brain atrophy for silent progression and conversion to secondary progressive disease (SPMS).

Methods

From a single‐center observational study, all RRMS (n = 360) and SPMS (n = 47) patients and 80 matched controls were evaluated. RRMS patient subsets who converted to SPMS (n = 54) or silently progressed (n = 159), respectively, during the 12‐year observation period were compared to clinically matched RRMS patients remaining RRMS (n = 54) or stable (n = 147), respectively. From brain MRI, we assessed the value of brain and spinal cord measures to predict silent progression and SPMS conversion.

Results

Patients who developed SPMS showed faster cord atrophy rates (−2.19%/yr) at least 4 years before conversion compared to their RRMS matches (−0.88%/yr, p < 0.001). Spinal cord atrophy rates decelerated after conversion (−1.63%/yr, p = 0.010) towards those of SPMS patients from study entry (−1.04%). Each 1% faster spinal cord atrophy rate was associated with 69% (p < 0.0001) and 53% (p < 0.0001) shorter time to silent progression and SPMS conversion, respectively.

Interpretation

Silent progression and conversion to secondary progressive disease are predominantly related to cervical cord atrophy. This atrophy is often present from the earliest disease stages and predicts the speed of silent progression and conversion to Progressive MS. Diagnosis of SPMS is rather a late recognition of this neurodegenerative process than a distinct disease phase. ANN NEUROL 2022;91:268–281

[Differential diagnostics of autoimmune inflammatory spinal cord diseases]

Myelitis is an acute or subacute inflammatory syndrome of the spinal cord. Myelopathy, often used as a synonym and presenting with similar symptoms in clinical practice, can be caused by numerous, not primarily inflammatory etiologies and might also show a progressive disease course. Within the last decade the spectrum of autoimmune myelitis was significantly broadened as was the spectrum of diagnostic methods. Apart from the characteristic example of multiple sclerosis with short-length myelitis and neuromyelitis optica spectrum disorders with longitudinally extensive transverse myelitis, multiple rare but important differential diagnoses should also be considered. Magnetic resonance imaging and laboratory analyses of serum antibodies and cerebrospinal fluid are the most important diagnostic methods and are fundamental for rapid treatment decisions, subsequently with better prognosis. This article reviews representative diseases within the spectrum of autoimmune spinal cord diseases and their differential diagnoses.

A pilot study of oxidative pathways in MS fatigue: randomized trial of N-acetyl cysteine

Objective

To assess feasibility, tolerability, and safety of N‐acetyl cysteine (NAC) for fatigue in progressive MS. Secondary objectives evaluated changes in fatigue and oxidative pathway biomarkers on NAC versus placebo.

Methods

Individuals with progressive MS with Modified Fatigue Impact Scale (MFIS) > t38 were randomized 2:1 to NAC 1250mg TID or placebo for 4 weeks. The primary outcome was tolerability and safety. The secondary outcome to evaluate efficacy was MFIS change from baseline to week 4 between groups. Exploratory biomarker outcomes included change in blood GSH/GSSG ratio (reduced‐to‐oxidized glutathione (GSH)) and in vivo relative GSH using 7T MR spectroscopy (MRS) between groups. Fisher exact test was used for categorical and rank sum for continuous outcomes.

Results

Fifiteen were randomized (10 NAC, 5 placebo; mean age 56.1 years, 80% female, median EDSS 6.0). At least one adverse event (AE) occurred in 60% on NAC versus 80% on placebo (p = 0.75). There were two AEs attributed to NAC in one patient (abdominal pain and constipation), with 94% adherence to NAC. MFIS decreased in both groups at week 4, with the mean improvement of 11‐points on NAC versus 18‐points on placebo (p = 0.33). GSH/GSSG ratio decreased on placebo (−0.6) and NAC (−0.1) (p = 0.18). Change in GSH levels to total creatine in anterior and posterior cingulate cortex, insula, caudate, putamen, and thalamus did not differ between groups.

Interpretation

NAC was well‐tolerated in progressive MS, although reduction in fatigue on NAC was similar to placebo. Antioxidant blood and MRS biomarkers were not significantly altered by NAC, which could be due to dose, route of administration, time of sample collection, short half‐life, or lack of effect.

Registered

clinicaltrials.gov NCT02804594.

Neurofilament light chain, a biomarker for polyneuropathy in systemic amyloidosis

OBJECTIVE

To study serum neurofilament light chain (sNfL) in amyloid light chain (AL) amyloidosis patients with and without polyneuropathy (PNP) and to corroborate previous observations that sNfL is increased in hereditary transthyretin-related (ATTRv) amyloidosis patients with PNP.

METHODS

sNfL levels were assessed retrospectively in patients with AL amyloidosis with and without PNP (AL/PNP+ and AL/PNP-, respectively), patients with ATTRv amyloidosis and PNP (ATTRv/PNP+), asymptomatic transthyretin (TTR) gene mutation carriers (TTRv carriers) and healthy controls. Healthy controls (HC) were age- and sex-matched to both AL/PNP- (HC/AL) and TTRv carriers (HC/TTRv). The single-molecule array (Simoa) assay was used to assess sNfL levels.

RESULTS

sNfL levels were increased both in 10 AL/PNP+ patients (p < .001) and in 10 AL/PNP- patients (p < .005) compared to 10 HC/AL individuals. sNfL levels were higher in AL/PNP+ patients than in AL/PNP- patients (p < .005). sNfL levels were also increased in 15 ATTRv/PNP+ patients, compared to both 15 HC/TTRv (p < .0001) and 15 TTRv carriers (p < .0001). ATTRv/PNP+ patients with progressive PNP (PND-score > I) had the highest sNfL levels compared to patients with early PNP (PND-score I) (p = .05). sNfL levels did not differ between TTRv carriers and HC/TTRv individuals. In the group comprising all healthy controls and in the group of TTRv carriers, sNfL levels correlated with age.

CONCLUSION

sNfL levels are increased in patients with PNP in both AL and ATTRv amyloidosis and are related to severity of PNP in ATTRv amyloidosis. sNfL is a promising biomarker to detect PNP, not only in ATTRv but also in AL amyloidosis.

Gut microbiota-specific IgA+ B cells traffic to the CNS in active multiple sclerosis

Changes in gut microbiota composition and a diverse role of B cells have recently been implicated in multiple sclerosis (MS), a central nervous system (CNS) autoimmune disease. Immunoglobulin A (IgA) is a key regulator at the mucosal interface. However, whether gut microbiota shape IgA responses and what role IgA⁺ cells have in neuroinflammation are unknown. Here, we identify IgA-bound taxa in MS and show that IgA-producing cells specific for MS-associated taxa traffic to the inflamed CNS, resulting in a strong, compartmentalized IgA enrichment in active MS and other neuroinflammatory diseases. Unlike previously characterized polyreactive anti-commensal IgA responses, CNS IgA cross-reacts with surface structures on specific bacterial strains but not with brain tissue. These findings establish gut microbiota-specific IgA⁺ cells as a systemic mediator in MS and suggest a critical role of mucosal B cells during active neuroinflammation with broad implications for IgA as an informative biomarker and IgA-producing cells as an immune subset to harness for therapeutic interventions.

Neurite Orientation Dispersion and Density Imaging for Assessing Acute Inflammation and Lesion Evolution in MS

BACKGROUND AND PURPOSE

MR imaging is essential for MS diagnosis and management, yet it has limitations in assessing axonal damage and remyelination. Gadolinium-based contrast agents add value by pinpointing acute inflammation and blood-brain barrier leakage, but with drawbacks in safety and cost. Neurite orientation dispersion and density imaging (NODDI) assesses microstructural features of neurites contributing to diffusion imaging signals. This approach may resolve the components of MS pathology, overcoming conventional MR imaging limitations.

MATERIALS AND METHODS

Twenty-one subjects with MS underwent serial enhanced MRIs (12.6 ± 9 months apart) including NODDI, whose key metrics are the neurite density and orientation dispersion index. Twenty-one age- and sex-matched healthy controls underwent unenhanced MR imaging with the same protocol. Fifty-eight gadolinium-enhancing and non-gadolinium-enhancing lesions were semiautomatically segmented at baseline and follow-up. Normal-appearing WM masks were generated by subtracting lesions and dirty-appearing WM from the whole WM.

RESULTS

The orientation dispersion index was higher in gadolinium-enhancing compared with non-gadolinium-enhancing lesions; logistic regression indicated discrimination, with an area under the curve of 0.73. At follow-up, in the 58 previously enhancing lesions, we identified 2 subgroups based on the neurite density index change across time: Type 1 lesions showed increased neurite density values, whereas type 2 lesions showed decreased values. Type 1 lesions showed greater reduction in size with time compared with type 2 lesions.

CONCLUSIONS

NODDI is a promising tool with the potential to detect acute MS inflammation. The observed heterogeneity among lesions may correspond to gradients in severity and clinical recovery after the acute phase.

Imaging correlates of visual function in multiple sclerosis

No single neuroimaging technique or sequence is capable of reflecting the functional deficits manifest in MS. Given the interest in imaging biomarkers for short- to medium-term studies, we aimed to assess which imaging metrics might best represent functional impairment for monitoring in clinical trials. Given the complexity of functional impairment in MS, however, it is useful to isolate a particular functionally relevant pathway to understand the relationship between imaging and neurological function. We therefore analyzed existing data, combining multiparametric MRI and OCT to describe MS associated visual impairment. We assessed baseline data from fifty MS patients enrolled in ReBUILD, a prospective trial assessing the effect of a remyelinating drug (clemastine). Subjects underwent 3T MRI imaging, including Neurite Orientation Dispersion and Density Imaging (NODDI), myelin content quantification, and retinal imaging, using OCT. Visual function was assessed, using low-contrast letter acuity. MRI and OCT data were studied to model visual function in MS, using a partial, least-squares, regression analysis. Measures of neurodegeneration along the entire visual pathway, described most of the observed variance in visual disability, measured by low contrast letter acuity. In those patients with an identified history of ON, however, putative myelin measures also showed correlation with visual performance. In the absence of clinically identifiable inflammatory episodes, residual disability correlates with neurodegeneration, whereas after an identifiable exacerbation, putative measures of myelin content are additionally informative.

Genome-wide association study of pathological gambling

Background

Pathological gambling is a behavioural addiction with negative economic, social, and psychological consequences. Identification of contributing genes and pathways may improve understanding of aetiology and facilitate therapy and prevention. Here, we report the first genome-wide association study of pathological gambling. Our aims were to identify pathways involved in pathological gambling, and examine whether there is a genetic overlap between pathological gambling and alcohol dependence.

Methods

Four hundred and forty-five individuals with a diagnosis of pathological gambling according to the Diagnostic and Statistical Manual of Mental Disorders were recruited in Germany, and 986 controls were drawn from a German general population sample. A genome-wide association study of pathological gambling comprising single marker, gene-based, and pathway analyses, was performed. Polygenic risk scores were generated using data from a German genome-wide association study of alcohol dependence.

Results

No genome-wide significant association with pathological gambling was found for single markers or genes. Pathways for Huntington's disease (P-value = 6.63 × 10−3); 5′-adenosine monophosphate-activated protein kinase signalling (P-value = 9.57 × 10−3); and apoptosis (P-value = 1.75 × 10−2) were significant. Polygenic risk score analysis of the alcohol dependence dataset yielded a one-sided nominal significant P-value in subjects with pathological gambling, irrespective of comorbid alcohol dependence status.

Conclusions

The present results accord with previous quantitative formal genetic studies which showed genetic overlap between non-substance- and substance-related addictions. Furthermore, pathway analysis suggests shared pathology between Huntington's disease and pathological gambling. This finding is consistent with previous imaging studies.

Intersubject Variability and Normalization Strategies for Spinal Cord Total Cross-Sectional and Gray Matter Areas

BACKGROUND AND PURPOSE

The quantification of spinal cord (SC) atrophy by MRI has assumed an important role in assessment of neuroinflammatory/neurodegenerative diseases and traumatic SC injury. Recent technical advances make possible the quantification of gray matter (GM) and white matter tissues in clinical settings. However, the goal of a reliable diagnostic, prognostic or predictive marker is still elusive, in part due to large intersubject variability of SC areas. Here, we investigated the sources of this variability and explored effective strategies to reduce it.

METHODS

One hundred twenty-nine healthy subjects (mean age: 41.0 ± 15.9) underwent MRI on a Siemens 3T Skyra scanner. Two-dimensional PSIR at the C2-C3 vertebral level and a sagittal 1 mm³ 3D T1-weighted brain acquisition extended to the upper cervical cord were acquired. Total cross-sectional area and GM area were measured at C2-C3, as well as measures of the vertebra, spinal canal and the skull. Correlations between the different metrics were explored using Pearson product-moment coefficients. The most promising metrics were used to normalize cord areas using multiple regression analyses.

RESULTS

The most effective normalization metrics were the V-scale (from SienaX) and the product of the C2-C3 spinal canal diameters. Normalization methods based on these metrics reduced the intersubject variability of cord areas of up to 17.74%. The measured cord areas had a statistically significant sex difference, while the effect of age was moderate.

CONCLUSIONS

The present work explored in a large cohort of healthy subjects the source of intersubject variability of SC areas and proposes effective normalization methods for its reduction.

Peripheral neuropathy in antineutrophil cytoplasmic antibody-associated vasculitides: Insights from the DCVAS study

Objective

Reported prevalence of vasculitic neuropathy (VN) in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is highly variable, and associations with other organ manifestations have not been studied systematically while accounting for diagnostic certainty of VN.

Methods

Data of all patients with AAV within the Diagnostic and Classification criteria for primary systemic VASculitis study were analyzed cross-sectionally. VN was categorized as definite (histology proven), probable (multiple mononeuropathy or nerve biopsy consistent with vasculitis), or possible (all others). Associations with other organ manifestations were compared in patients with and without VN.

Results

Nine hundred fifty-five patients (mean age 57 years, range 18–91 years, 51% female) were identified. Of these, 572 had granulomatosis with polyangiitis (GPA), 218 microscopic polyangiitis (MPA), and 165 eosinophilic granulomatosis with polyangiitis (EGPA). The prevalence of VN was 65% in EGPA, 23% in MPA, and 19% in GPA. Nerve biopsy was performed in 32/269 (12%) patients, demonstrating definite vasculitis in 17/32 (53%) of patients. VN was associated with myeloperoxidase-ANCA positivity (p = 0.004) and skin (p < 0.001), musculoskeletal, (p < 0.001) and cardiovascular (p = 0.005) involvement. Patients with VN were less likely to have renal (p < 0.001), eye (p < 0.001), and gastrointestinal (p = 0.023) involvement.

Conclusions

Our study provides comprehensive insights into the prevalence and organ associations of VN in a large, systematically collected AAV cohort. VN is most commonly associated with skin, musculoskeletal, and cardiovascular manifestations. In routine clinical practice, diagnosis of VN is infrequently confirmed by the gold standard of nerve biopsy but rather supported by the clinical setting of active systemic AAV.

IL-17A is associated with the breakdown of the blood-brain barrier in relapsing-remitting multiple sclerosis

IL-17 has been implicated in the pathogenesis of multiple sclerosis (MS). Here, we show that blockade of IL-17A, but not IL-17F, attenuated experimental autoimmune encephalomyelitis (EAE). We further show that IL-17A levels were elevated in the CSF of relapsing-remitting MS (RRMS) patients and that they correlated with the CSF/serum albumin quotient (Qalb), a measure of blood-brain barrier (BBB) dysfunction. We then demonstrated that the combination of IL-17A and IL-6 reduced the expression of tight junction (TJ)-associated genes and disrupted monolayer integrity in the BBB cell line hCMEC/D3. However, unlike IL-17A, IL-6 in the CSF from RRMS patients did not correlate with Qalb. These data highlight the potential importance of targeting IL-17A in preserving BBB integrity in RRMS.

Silent progression in disease activity-free relapsing multiple sclerosis

Objective

Rates of worsening and evolution to secondary progressive multiple sclerosis (MS) may be substantially lower in actively treated patients compared to natural history studies from the pretreatment era. Nonetheless, in our recently reported prospective cohort, more than half of patients with relapsing MS accumulated significant new disability by the 10th year of follow‐up. Notably, “no evidence of disease activity” at 2 years did not predict long‐term stability. Here, we determined to what extent clinical relapses and radiographic evidence of disease activity contribute to long‐term disability accumulation.

Methods

Disability progression was defined as an increase in Expanded Disability Status Scale (EDSS) of 1.5, 1.0, or 0.5 (or greater) from baseline EDSS = 0, 1.0–5.0, and 5.5 or higher, respectively, assessed from baseline to year 5 (±1 year) and sustained to year 10 (±1 year). Longitudinal analysis of relative brain volume loss used a linear mixed model with sex, age, disease duration, and HLA‐DRB1*15:01 as covariates.

Results

Relapses were associated with a transient increase in disability over 1‐year intervals (p = 0.012) but not with confirmed disability progression (p = 0.551). Relative brain volume declined at a greater rate among individuals with disability progression compared to those who remained stable (p < 0.05).

Interpretation

Long‐term worsening is common in relapsing MS patients, is largely independent of relapse activity, and is associated with accelerated brain atrophy. We propose the term silent progression to describe the insidious disability that accrues in many patients who satisfy traditional criteria for relapsing–remitting MS. Ann Neurol 2019;85:653–666

Longitudinally persistent cerebrospinal fluid B cells can resist treatment in multiple sclerosis

B cells are key contributors to chronic autoimmune pathology in multiple sclerosis (MS). Clonally related B cells exist in the cerebrospinal fluid (CSF), meninges, and CNS parenchyma of MS patients. We sought to investigate the presence of clonally related B cells over time by performing Ig heavy chain variable region repertoire sequencing on B cells from longitudinally collected blood and CSF samples of MS patients (n = 10). All patients were untreated at the time of the initial sampling; the majority (n = 7) were treated with immune-modulating therapies 1.2 (±0.3 SD) years later during the second sampling. We found clonal persistence of B cells in the CSF of 5 patients; these B cells were frequently Ig class-switched and CD27+. Specific blood B cell subsets appear to provide input into CNS repertoires over time. We demonstrate complex patterns of clonal B cell persistence in CSF and blood, even in patients on immune-modulating therapy. Our findings support the concept that peripheral B cell activation and CNS-compartmentalized immune mechanisms can in part be therapy resistant.

Measurement of spinal cord atrophy using phase sensitive inversion recovery (PSIR) imaging in motor neuron disease

BACKGROUND

The spectrum of motor neuron disease (MND) includes numerous phenotypes with various life expectancies. The degree of upper and lower motor neuron involvement can impact prognosis. Phase sensitive inversion recovery (PSIR) imaging has been shown to detect in vivo gray matter (GM) and white matter (WM) atrophy in the spinal cord of other patient populations but has not been explored in MND.

METHODS

In this study, total cord, WM and GM areas of ten patients with a diagnosis within the MND spectrum were compared to those of ten healthy controls (HC). Patients' diagnosis included amyotrophic lateral sclerosis (ALS), primary lateral sclerosis, primary muscular atrophy, facial onset sensory and motor neuronopathy and ALS-Frontotemporal dementia. Axial 2D PSIR images were acquired at four cervical disc levels (C2-C3, C3-C4, C5-C6 and C7-T1) with a short acquisition time (2 minutes) protocol. Total cross-sectional areas (TCA), GM and WM areas were measured using a combination of highly reliable manual and semi-automated methods. Cord areas in MND patients were compared with HC using linear regression analyses adjusted for age and sex. Correlation of WM and GM areas in MND patients was explored to gain insights into underlying atrophy patterns.

RESULTS

MND patients as a group had significantly smaller cervical cord GM area compared to HC at all four levels (C2-C3: p = .009; C3-C4: p = .001; C5-C6: p = .006; C7-T1: p = .002). WM area at C5-C6 level was significantly smaller (p = .001). TCA was significantly smaller at C3-C4 (p = .018) and C5-C6 (p = .002). No significant GM and WM atrophy was detected in the two patients with predominantly bulbar phenotype. Concomitant GM and WM atrophy was detected in solely upper or lower motor neuron level phenotypes. There was a significant correlation between GM and WM areas at all four levels in this diverse population of MND.

CONCLUSION

Spinal cord GM and WM atrophy can be detected in vivo in patients within the MND spectrum using a short acquisition time 2D PSIR imaging protocol. PSIR imaging shows promise as a method for quantifying spinal cord involvement and thus may be useful for diagnosis, prognosis and for monitoring disease progression.

Advances in Imaging Multiple Sclerosis

Neuroimaging has emerged as a powerful technology that has enabled visualization of the impact of multiple sclerosis (MS) on the central nervous system in vivo with unprecedented precision. It has played a crucial role in disentangling the chronology of inflammation and neurodegeneration, developing and understanding mechanisms of novel therapeutics, and diagnosing and monitoring the disease in the clinical setting. However, challenges pertaining to the limited resolution, lack of specificity, inherent technological biases, and processing of increasingly big datasets have hindered comprehensive insights into the pathology underlying disability.

Here, we review the advances in neuroimaging for MS that have moved the field forward in recent years by addressing the above-mentioned issues, thereby enhancing our knowledge of this yet enigmatic disease. We discuss complementary imaging technologies, including magnetic resonance imaging, positron emission tomography, and optical coherence tomography, the most recent tool in the MS imaging armamentarium that holds promise to act as a surrogate of pathological changes in the central nervous system in a more easily accessible way.

Clonal relationships of CSF B cells in treatment-naive multiple sclerosis patients

A role of B cells in multiple sclerosis (MS) is well established, but there is limited understanding of their involvement during active disease. Here, we examined cerebrospinal fluid (CSF) and peripheral blood (PB) B cells in treatment-naive patients with MS or high-risk clinically isolated syndrome. Using flow cytometry, we found increased CSF lymphocytes with a disproportionate increase of B cells compared with T cells in patients with gadolinium-enhancing (Gd+) lesions on brain MRI. Ig gene heavy chain variable region (Ig-VH) repertoire sequencing of CSF and PB B cells revealed clonal relationships between intrathecal and peripheral B cell populations, which could be consistent with migration of B cells to and activation in the CNS in active MS. In addition, we found evidence for bystander immigration of B cells from the periphery, which could be supported by a CXCL13 gradient between CSF and blood. Understanding what triggers B cells to migrate and home to the CNS may ultimately aid in the rational selection of therapeutic strategies to limit progression in MS.

Gradient nonlinearity effects on upper cervical spinal cord area measurement from 3D T1 -weighted brain MRI acquisitions

PURPOSE

To explore (i) the variability of upper cervical cord area (UCCA) measurements from volumetric brain 3D T₁ -weighted scans related to gradient nonlinearity (GNL) and subject positioning; (ii) the effect of vendor-implemented GNL corrections; and (iii) easily applicable methods that can be used to retrospectively correct data.

METHODS

A multiple sclerosis patient was scanned at seven sites using 3T MRI scanners with the same 3D T₁ -weighted protocol without GNL-distortion correction. Two healthy subjects and a phantom were additionally scanned at a single site with varying table positions. The 2D and 3D vendor-implemented GNL-correction algorithms and retrospective methods based on (i) phantom data fit, (ii) normalization with C2 vertebral body diameters, and (iii) the Jacobian determinant of nonlinear registrations to a template were tested.

RESULTS

Depending on the positioning of the subject, GNL introduced up to 15% variability in UCCA measurements from volumetric brain T₁ -weighted scans when no distortion corrections were used. The 3D vendor-implemented correction methods and the three proposed methods reduced this variability to less than 3%.

CONCLUSIONS

Our results raise awareness of the significant impact that GNL can have on quantitative UCCA studies, and point the way to prospectively and retrospectively managing GNL distortions in a variety of settings, including clinical environments. Magn Reson Med 79:1595-1601, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Onset of secondary progressive MS after long-term rituximab therapy - a case report

A patient with relapsing multiple sclerosis (RMS) was treated with a standard immunomodulatory therapy, but due to ongoing disease activity was switched to rituximab. Relapses ceased, but secondary progressive MS (SPMS) eventually appeared, associated with new focal spinal cord white matter lesions. Cerebrospinal fluid (CSF) showed persistent oligoclonal bands (OCB) and clonally related B cells in CSF and peripheral blood. The treatment escalation approach failed to prevent evolution to SPMS, raising the question of whether initiation of B‐cell depleting therapy at the time of RMS diagnosis should be tested to more effectively address the immune pathology leading to SPMS.

[Migration Background and Pathological Gambling: Results of a Nationwide Epidemiological Study on the Impact of Region of Origin in Germany]

OBJECTIVE

To investigate the extent to which the presence and number of symptoms of pathological gambling (PG), distinguished by region of origin (RO), differ.

METHODS

Data was obtained from a nationwide telephone survey of 15 023 individuals living in Germany and aged 14-64 years. They were categorized according to their RO and the number of symptoms of PG (0-10 DSM-IV-criteria).

RESULTS

The lifetime prevalence of PG symptoms is 18.1% for people of the RO Turkey, 9.0% for those of the RO Yugoslavia and 6.8% for those without a migration background. Compared to the latter, the two-part count data regression method showed a higher chance of PG symptoms for the RO Turkey as well as a 70.3 and 87.2% increase in the number of symptoms for the RO Turkey and Yugoslavia, respectively.

CONCLUSION

The RO could independently contribute to the presence and amount of symptoms of PG.

Power estimation for non-standardized multisite studies

A concern for researchers planning multisite studies is that scanner and T1-weighted sequence-related biases on regional volumes could overshadow true effects, especially for studies with a heterogeneous set of scanners and sequences. Current approaches attempt to harmonize data by standardizing hardware, pulse sequences, and protocols, or by calibrating across sites using phantom-based corrections to ensure the same raw image intensities. We propose to avoid harmonization and phantom-based correction entirely. We hypothesized that the bias of estimated regional volumes is scaled between sites due to the contrast and gradient distortion differences between scanners and sequences. Given this assumption, we provide a new statistical framework and derive a power equation to define inclusion criteria for a set of sites based on the variability of their scaling factors. We estimated the scaling factors of 20 scanners with heterogeneous hardware and sequence parameters by scanning a single set of 12 subjects at sites across the United States and Europe. Regional volumes and their scaling factors were estimated for each site using Freesurfer's segmentation algorithm and ordinary least squares, respectively. The scaling factors were validated by comparing the theoretical and simulated power curves, performing a leave-one-out calibration of regional volumes, and evaluating the absolute agreement of all regional volumes between sites before and after calibration. Using our derived power equation, we were able to define the conditions under which harmonization is not necessary to achieve 80% power. This approach can inform choice of processing pipelines and outcome metrics for multisite studies based on scaling factor variability across sites, enabling collaboration between clinical and research institutions.

MRI monitoring of pathological changes in the spinal cord in patients with multiple sclerosis

The spinal cord is a clinically important site that is affected by pathological changes in most patients with multiple sclerosis; however, imaging of the spinal cord with conventional MRI can be difficult. Improvements in MRI provide a major advantage for spinal cord imaging, with better signal-to-noise ratio and improved spatial resolution. Through the use of multiplanar MRI, identification of diffuse and focal changes in the whole spinal cord is now routinely possible. Corroborated by related histopathological analyses, several new techniques, such as magnetisation transfer, diffusion tension imaging, functional MRI, and proton magnetic resonance spectroscopy, can detect non-focal, spinal cord pathological changes in patients with multiple sclerosis. Additionally, functional MRI can reveal changes in the response pattern to sensory stimulation in patients with multiple sclerosis. Through use of these techniques, findings of cord atrophy, intrinsic cord damage, and adaptation are shown to occur largely independently of focal spinal cord lesion load, which emphasises their relevance in depiction of the true burden of disease. Combinations of magnetisation transfer ratio or diffusion tension imaging indices with cord atrophy markers seem to be the most robust and meaningful biomarkers to monitor disease evolution in early multiple sclerosis.

Ultrasound of the peripheral nerves in systemic vasculitic neuropathies

INTRODUCTION

Ultrasound of the peripheral nerves (PNUS) can be used to visualize nerve pathologies in polyneuropathies (PNP). The aim of this study was to investigate, whether PNUS provides additional information in patients with proven systemic vasculitic neuropathies (VN).

MATERIAL AND METHODS

Systematic ultrasound measurements of several peripheral nerves, the vagal nerve and the 6th cervical nerve root were performed in 14 patients and 22 healthy controls. Nerve conduction studies of the corresponding nerves were undertaken. Finally, the measured results were compared to a study population of demyelinating immune-mediated and axonal neuropathies.

RESULTS

Patients with VN displayed significant smaller amplitudes of compound muscle action potentials (CMAP) (p<0.05) and sensory nerve action potentials (SNAP) compared to healthy controls, while conduction velocity did not differ between groups. The mean nerve cross-sectional areas (CSA) were increased in several peripheral nerves compared to the controls, most prominent in tibial and fibular nerve (p<0.01). PNUS revealed nerve enlargement in most of the clinically and electrophysiologically affected nerves (22 out of 31) in VN. Nerve enlargement was more often seen in vasculitic neuropathies than in other axonal neuropathies, but significantly rarer than in demyelinating neuropathies.

CONCLUSION

Focal CSA enlargement in one or more nerves in electrophysiologically axonal neuropathies can be a hint for VN and thus facilitate diagnostic and therapeutic procedures.

Prevalence of suicide attempts in pathological gamblers in a nationwide Austrian treatment sample

BACKGROUND

For pathological gambling (PG), a 12-month prevalence rate of up to 0.66% has been reported. Multiple financial, occupational and relationship problems and losses, humiliation of the person and the environment are possible side effects and may lead to hopelessness, suicidal ideation and suicidal behavior. Suicide attempt rates among pathological gamblers of between 4% and 40% and suicidal ideation of between 12% and 92% have been reported.

AIM

This study aims at assessing the prevalence of suicide attempts in PG and at elucidating differences between the patients with and without suicide attempt history (SAH) in a large nationwide Austrian sample.

METHODS

Between 2002 and 2011, the Austrian Society for the Research of Non-Substance Related Addiction collected 862 questionnaires of pathological gamblers undergoing outpatient and inpatient treatment for PG in Austria.

RESULTS

(a) Of all pathological gamblers, 9.7% had an SAH. (b) The SAH group suffered significantly more from a comorbid disorder and was more often in previous inpatient treatments. (c) The SAH patients had a longer time of an abstinence period in their PG career.

DISCUSSION

One in 10 pathological gamblers has an SAH, demonstrating the relevance of suicidality in this population. Significant differences for several parameters were found for PG with and without SAH. However, a regression analysis only explained 15% of the variance. This suggests that suicidality must be considered in pathological gamblers in general.

Interferon beta-associated recurrence of painful trigeminal neuropathy attributed to a multiple sclerosis plaque

We report the case of a 49-year-old woman with painful trigeminal neuropathy in the right maxillary division attributed to a multiple sclerosis plaque as the presenting symptom of multiple sclerosis. The patient was initially treated with intravenous corticosteroids and was pain free on pregabalin for six months. She was then started on an immunomodulatory treatment and coinciding with the up-titration of interferon beta-1a, she experienced recurrence of painful trigeminal neuropathy as well as weekly migraine attacks. Worsening of primary headache disorders by interferon treatment has been previously reported. Our case suggests that treatment with interferon beta may also exacerbate symptomatic trigeminal neuralgia in multiple sclerosis.

Control of domain wall polarity by current pulses

Direct observation of current-induced propagation of purely transverse magnetic domain walls with spin-polarized scanning electron microscopy is reported in Fe30Ni70 nanowires. After propagation, the domain walls keep their transverse nature but switch polarity in some cases. For uniform Ni70Fe30 wires, the effect is random and illustrates domain-wall propagation above the Walker threshold. In the case of Ni{70}Fe_{30}/Fe wires, the transverse magnetization component in the wall is entirely determined by the polarity of the current pulse, an effect that is not reconciled by present theories even when taking into account the nonuniform Oersted field generated by the current.

Expression of the glycodelin A gene and the detection of its protein in tissues and serum of ovarian carcinoma patients

BACKGROUND

Glycodelin A (GdA), also known as placental protein 14 (PP14), has been detected in endometrial, cervical and ovarian carcinoma cells. It is suspected to be a marker of human ovarian cancer tissues.

MATERIALS AND METHODS

We investigated serum, tissue and cyst fluid samples of patients with an ovarian carcinoma in contrast to patients with benign and malignant diseases such as uterine myoma, endometriosis, cervical, uterine and breast cancer, and metastases of bladder and colon carcinoma. Used methods were enzyme-immunoassay, immunohistochemistry (IHC) and polymerase chain reaction (PCR).

RESULTS

In 81% of the control group the GdA-expression was negative, which was confirmed by IHC and PCR. Of the ovarian carcinoma group only 52% showed correspondence between IHC and PCR.

CONCLUSION

These results indicate that determination of GdA is not sensitive or specific enough for use as a tumour marker.