The association of high levels of autoantibodies to glutamic acid decarboxylase (GAD-ab) and stiff-person syndrome (SPS) is well known. However, the full spectrum of neurological syndromes associated ...with GAD-ab is not well established. In addition, these patients usually present type 1 diabetes mellitus (DM1) that could justify the presence of high GAD-ab levels. To clarify these issues, we reviewed the clinical and immunological features of patients in whom high GAD-ab levels were detected in a reference centre for DM1 and for the detection of antineuronal antibodies in suspected paraneoplastic neurological syndromes (PNS). High GAD-ab levels were defined as values ≥2000 U/ml by radioimmunoassay. Intrathecal synthesis (IS) of GAD-ab was calculated in paired serum/CSF samples. Values higher than the IgG index were considered indicators for positive GAD-ab-specific IS. High GAD-ab levels were identified in 61 patients, 22 (36%) had SPS, 17 (28%) cerebellar ataxia, 11 (18%) other neurological disorders (epilepsy—four, PNS—four; idiopathic limbic encephalitis—two; myasthenia gravis—one), and 11 (18%) isolated DM1. Patients with SPS and cerebellar ataxia had the same frequency of female gender (86% vs 94%), DM1 (59% vs 53%), CSF oligoclonal bands (35% vs 69%). Three of the four PNS patients, with paraneoplastic encephalomyelitis, a predominant gait cerebellar ataxia, and limbic encephalitis, had neuroendocrine carcinomas. GAD expression was confirmed in the two tumours in which the study was done. The fourth patient presented with paraneoplastic cerebellar degeneration antedating a lung adenocarcinoma. The frequency of increased IS of GAD-ab was 85% in SPS, 100% in cerebellar ataxia, and 86% in other neurological disorders. In conclusion, our study emphasizes that high GAD-ab levels associate with other neurological disorders besides SPS. Cerebellar ataxia, the second most common syndrome associated with high GAD-ab levels, shares with SPS the same demographic, clinical and immunological features. The demonstration of an increased IS of GAD-ab is important to confirm that the GAD autoimmunity is related to the neurological syndrome particularly when there is a concomitant DM1 that could justify the presence of high GAD-ab levels. Lastly, in patients who develop neurological syndromes that suggest a PNS, the finding of GAD-ab does not rule out this possibility and appropriate studies should be done to confirm an underlying cancer.
Background
Manual brain extraction from magnetic resonance (MR) images is time‐consuming and prone to intra‐ and inter‐rater variability. Several automated approaches have been developed to alleviate ...these constraints, including deep learning pipelines. However, these methods tend to reduce their performance in unseen magnetic resonance imaging (MRI) scanner vendors and different imaging protocols.
Purpose
To present and evaluate for clinical use PARIETAL, a pre‐trained deep learning brain extraction method. We compare its reproducibility in a scan/rescan analysis and its robustness among scanners of different manufacturers.
Study Type
Retrospective.
Population
Twenty‐one subjects (12 women) with age range 22–48 years acquired using three different MRI scanner machines including scan/rescan in each of them.
Field Strength/Sequence
T1‐weighted images acquired in a 3‐T Siemens with magnetization prepared rapid gradient‐echo sequence and two 1.5 T scanners, Philips and GE, with spin‐echo and spoiled gradient‐recalled (SPGR) sequences, respectively.
Assessment
Analysis of the intracranial cavity volumes obtained for each subject on the three different scanners and the scan/rescan acquisitions.
Statistical Tests
Parametric permutation tests of the differences in volumes to rank and statistically evaluate the performance of PARIETAL compared to state‐of‐the‐art methods.
Results
The mean absolute intracranial volume differences obtained by PARIETAL in the scan/rescan analysis were 1.88 mL, 3.91 mL, and 4.71 mL for Siemens, GE, and Philips scanners, respectively. PARIETAL was the best‐ranked method on Siemens and GE scanners, while decreasing to Rank 2 on the Philips images. Intracranial differences for the same subject between scanners were 5.46 mL, 27.16 mL, and 30.44 mL for GE/Philips, Siemens/Philips, and Siemens/GE comparison, respectively. The permutation tests revealed that PARIETAL was always in Rank 1, obtaining the most similar volumetric results between scanners.
Data Conclusion
PARIETAL accurately segments the brain and it generalizes to images acquired at different sites without the need of training or fine‐tuning it again. PARIETAL is publicly available.
Level of Evidence
2
Technical Efficacy Stage
2
Stigma associated with neurological disorders may contribute to a poor health-related quality of life. However, limited information is available in primary progressive multiple sclerosis. We ...investigated the presence and impact of stigma in patients with primary progressive multiple sclerosis. A non-interventional, cross-sectional study was conducted. A total of 55 primary progressive multiple sclerosis patients were studied (mean age 55.8±9.5 years, 56.4% male). The median Expanded Disability Status Scale score was 5.5 (4.0–6.5). Stigma prevalence was 78.2% (n=43). Twenty-four patients (43.6%) were classified as depressed. Scores on the eight-item Stigma Scale for Chronic Illness correlated with physical (rho=0.464, p<0.001) and psychological (rho=0.358, p=0.007) 29-item Multiple Sclerosis Impact Scale subscores. Stigma predicted concurrent depression (odds ratio=1.13; p=0.046). Stigma was highly prevalent with a detrimental effect on quality of life and mood in primary progressive multiple sclerosis.
In recent years, several convolutional neural network (CNN) methods have been proposed for the automated white matter lesion segmentation of multiple sclerosis (MS) patient images, due to their ...superior performance compared with those of other state-of-the-art methods. However, the accuracies of CNN methods tend to decrease significantly when evaluated on different image domains compared with those used for training, which demonstrates the lack of adaptability of CNNs to unseen imaging data. In this study, we analyzed the effect of intensity domain adaptation on our recently proposed CNN-based MS lesion segmentation method. Given a source model trained on two public MS datasets, we investigated the transferability of the CNN model when applied to other MRI scanners and protocols, evaluating the minimum number of annotated images needed from the new domain and the minimum number of layers needed to re-train to obtain comparable accuracy. Our analysis comprised MS patient data from both a clinical center and the public ISBI2015 challenge database, which permitted us to compare the domain adaptation capability of our model to that of other state-of-the-art methods. In both datasets, our results showed the effectiveness of the proposed model in adapting previously acquired knowledge to new image domains, even when a reduced number of training samples was available in the target dataset. For the ISBI2015 challenge, our one-shot domain adaptation model trained using only a single case showed a performance similar to that of other CNN methods that were fully trained using the entire available training set, yielding a comparable human expert rater performance. We believe that our experiments will encourage the MS community to incorporate its use in different clinical settings with reduced amounts of annotated data. This approach could be meaningful not only in terms of the accuracy in delineating MS lesions but also in the related reductions in time and economic costs derived from manual lesion labeling.
•We analyzed the effect of intensity domain adaptation on CNN MS lesion segmentation.•We evaluated the minimum number of images and layers needed to re-train the model.•The model showed good adaptation even when trained on very few or a single case.•The performance of models trained on one case was similar to other fully-trained CNN.•On ISBI0215, our model trained on one case was comparable to human rate performance.
Background:
REFINE was an exploratory, dose- and frequency-blinded, prospective, randomized, dose-ranging study in relapsing–remitting multiple sclerosis (RRMS) patients.
Objective:
To examine the ...efficacy, safety, and tolerability of natalizumab administered via various regimens in RRMS patients.
Methods:
Clinically stable RRMS patients previously treated with 300 mg natalizumab intravenously for ⩾12 months were randomized to one of six natalizumab regimens over 60 weeks: 300 mg administered intravenously or subcutaneously every 4 weeks (Q4W), 300 mg intravenously or subcutaneously every 12 weeks (Q12W), or 150 mg intravenously or subcutaneously Q12W. The primary endpoint was the mean cumulative number of combined unique active magnetic resonance imaging (MRI) lesions at week 60.
Results:
In total, 290 patients were enrolled. All Q12W dosing arms were associated with increased clinical and MRI disease activity and closed early; ⩾39.5% of patients in each Q12W arm met rescue criteria. In the 300 mg intravenous and subcutaneous Q4 W arms, the mean cumulative number of combined unique active MRI lesions was 0.23 and 0.02, respectively; annualized relapse rates were 0.07 and 0.08, respectively; and trough natalizumab serum levels and α4-integrin saturation were comparable.
Conclusion:
Natalizumab 300 mg subcutaneous Q4W was comparable to 300 mg intravenous Q4W dosing with respect to efficacy, pharmacokinetics/pharmacodynamics, and safety.
Cognitive impairment has been reported at all phases and all subtypes of multiple sclerosis. It remains a major cause of neurological disability in young and middle-aged adults suffering from the ...disease. The severity and type of cognitive impairment varies considerably among individuals and can be observed both in early and in later stages. The areas which have commonly shown more deficits are: information processing speed, complex attention, memory, and executive function. Even though an alteration in both the white matter and in the gray matter has been found in patients with multiple sclerosis and cognitive impairment, the underlying process still remains unknown. Standardized neurological examinations fail to detect emerging cognitive deficits and self-reported cognitive complaints by the patients can be confounded by other subjective symptoms. This review is a comprehensive and short update of the literature on cognitive dysfunctions, the possible confounders and the impact of quality of life in patients with multiple sclerosis.
Automatic segmentation of multiple sclerosis (MS) lesions in brain MRI has been widely investigated in recent years with the goal of helping MS diagnosis and patient follow-up. However, the ...performance of most of the algorithms still falls far below expert expectations. In this paper, we review the main approaches to automated MS lesion segmentation. The main features of the segmentation algorithms are analysed and the most recent important techniques are classified into different strategies according to their main principle, pointing out their strengths and weaknesses and suggesting new research directions. A qualitative and quantitative comparison of the results of the approaches analysed is also presented. Finally, possible future approaches to MS lesion segmentation are discussed.
Sphingosine-1-phosphate (S1P) and S1P receptors (S1PR) are bioactive lipid molecules that are ubiquitously expressed in the human body and play an important role in the immune system. S1P-S1PR ...signaling has been well characterized in immune trafficking and activation in both innate and adaptive immune systems. Despite this knowledge, the full scope in the pathogenesis of autoimmune disorders is not well characterized yet. From the discovery of fingolimod, the first S1P modulator, until siponimod, the new molecule recently approved for the treatment of secondary progressive multiple sclerosis (SPMS), there has been a great advance in understanding the S1P functions and their involvement in immune diseases, including multiple sclerosis (MS). Modulation on S1P is an interesting target for the treatment of various autoimmune disorders. Improved understanding of the mechanism of action of fingolimod has allowed the development of the more selective second-generation S1PR modulators. Subtype 1 of the S1PR (S1PR1) is expressed on the cell surface of lymphocytes, which are known to play a major role in MS pathogenesis. The understanding of S1PR1’s role facilitated the development of pharmacological strategies directed to this target, and theoretically reduced the safety concerns derived from the use of fingolimod. A great advance in the MS treatment was achieved in March 2019 when the Food and Drug Association (FDA) approved Siponimod, for both active secondary progressive MS and relapsing–remitting MS. Siponimod became the first oral disease modifying therapy (DMT) specifically approved for active forms of secondary progressive MS. Additionally, for the treatment of relapsing forms of MS, ozanimod was approved by FDA in March 2020. Currently, there are ongoing trials focused on other new-generation S1PR1 modulators. This review approaches the fundamental aspects of the sphingosine phosphate modulators and their main similarities and differences.
Background:
Population-based studies on neuromyelitis optica spectrum disorders (NMOSD) are limited, and it is unclear whether the rates have changed with the implementation of the new 2015 criteria.
...Objectives:
To estimate the incidence and prevalence of NMOSD in Catalonia (Spain), using both the 2006 and the 2015 criteria.
Methods:
In this clinic-based retrospective study, patients diagnosed with NMOSD between 2006 and 2015 were identified using multiple sources, including direct contact to all Catalan hospitals, identification of cases through the Catalan Health Surveillance System, and registry of antibodies to aquaporin-4 (AQP4-IgG) and myelin oligodendrocyte glycoprotein (MOG-IgG) in a reference laboratory. The incidence rate was calculated for the period 1 January 2006–1 January 2016 and prevalence for the date 1 January 2016.
Results:
We identified 74 patients (by the 2015 criteria). Most patients were Caucasian (81%), and female (76%) with a median age at disease onset of 42 years (range, 10–76 years). In total, 54 (73%) patients were positive for AQP4-IgG, 11 (15%) double-seronegative, and 9 (12%) MOG-IgG-positive. Rates of incidence and prevalence (0.63/1,000,000 person-years and 0.89/100,000, respectively) were 1.5-fold higher than those reported by the 2006 criteria. Lowest rates were seen in children and elder people and highest in women and middle-aged people (40–59 years). The female predominance was lost in incident AQP4-IgG-seronegative children and AQP4-IgG-positive elder people. MOG-IgG and double-seronegativity contributed similarly but did not influence the long-term outcome.
Conclusion:
The new criteria increase the estimates, but NMOSD remains as a rare disease. The differences in age- and sex-specific estimates highlight the importance of the serologic classification.
Introduction
Multiple sclerosis (MS) is a serious disease typically occurring in the brain whose diagnosis and efficacy of treatment monitoring are vital. Magnetic resonance imaging (MRI) is ...frequently used in serial brain imaging due to the rich and detailed information provided.
Methods
Time-series analysis of images is widely used for MS diagnosis and patient follow-up. However, conventional manual methods are time-consuming, subjective, and error-prone. Thus, the development of automated techniques for the detection and quantification of MS lesions is a major challenge.
Results
This paper presents an up-to-date review of the approaches which deal with the time-series analysis of brain MRI for detecting active MS lesions and quantifying lesion load change. We provide a comprehensive reference source for researchers in which several approaches to change detection and quantification of MS lesions are investigated and classified. We also analyze the results provided by the approaches, discuss open problems, and point out possible future trends.
Conclusion
Lesion detection approaches are required for the detection of static lesions and for diagnostic purposes, while either quantification of detected lesions or change detection algorithms are needed to follow up MS patients. However, there is not yet a single approach that can emerge as a standard for the clinical practice, automatically providing an accurate MS lesion evolution quantification. Future trends will focus on combining the lesion detection in single studies with the analysis of the change detection in serial MRI.
PDF
