The recent 2017 modification have increased the sensitivity of McDonald criteria for MS. Nevertheless, some MS patients with atypical MRI findings have been identified, leading to prolonged delay to ...diagnosis and high costs to look for alternative diagnoses.
To describe a series of MS patients with atypical MRI presentation.
Patients with atypical MS were identified through a nationwide retrospective study. We established a five groups classification: tumefactive demyelinating lesion (TDL)-onset MS, acute disseminated encephalomyelitis (ADEM)-like MS, cavitary MS and leukodystrophy-like MS. All the patients meeting our radiological criteria for atypical MS were included.
A total of 57 patients met the inclusion criteria. 7 cases were classified in the TDL-onset group, 10 in the ADEM-like group, 26 in the cavitary group and 14 in the leukodystrophy-like group. Overall risk of conversion to MS after an isolated TDL was around 30% at five years. Patients in the TDL-onset and ADEM-like groups globally presented an acute onset and a relapsing-remitting evolution. Conversely, patients in the cavitary and leukodystrophy- groups largely evolved with a progressive and severe course.
A significant number of MS patients can have a striking atypical presentation and may be misdiagnosed. This preliminary analysis helps to refine the spectrum of atypical MS patients.
MRS allows to measure cerebral metabolites, thus helping to characterize brain disease diagnosis and followup. Metabolite concentration quantification is usually based on metabolite ratio referring ...to creatine. If this metabolite concentration is supposed to be constant, it may vary in pathological processes. Therefore, "absolute" concentration methodology is needed. The aim of this study is to validate a clinical "absolute" quantification protocol through the development of an external metabolic phantom, calibration and correction, and the investigation of reproducibility issues. When phantom stability was investigated by a short-term and a long-term reproducibility study, both Standard Deviations (SD) were in agreement with literature values. This "absolute" quantification method was applied to patients with Multiple Sclerosis (MS). The results show a significant decrease in both N-Acetyl Aspartate (NAA) and choline concentrations.
(2012) Correction: Correlation of Diffusion and Metabolic Alterations in Different Clinical Forms of Multiple Sclerosis. No competing interests declared.
Inherited white matter diseases are rare and heterogeneous disorders usually encountered in infancy. Adult-onset forms are increasingly recognized. Our objectives were to determine relative ...frequencies of genetic leukoencephalopathies in a cohort of adult-onset patients and to evaluate the effectiveness of a systematic diagnostic approach. Inclusion criteria of this retrospective study were: (i) symmetrical involvement of white matter on the first available brain MRI; (ii) age of onset above 16 years. Patients with acquired diseases were excluded. Magnetic resonance imaging analysis identified three groups (vascular, cavitary and non-vascular/non-cavitary) in which distinct genetic and/or biochemical testing were realized. One hundred and fifty-four patients (male/female = 60/94) with adult-onset leukoencephalopathies were identified. Mean age of onset was 38.6 years. In the vascular group, 41/55 patients (75%) finally had a diagnosis including CADASIL (cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy, n = 32) and COL4A1 mutation, n = 7. In the cavitary group, 13/17 (76%) patients had a diagnosis of EIF2B-related disorder. In the third group (n = 82), a systematic biological screening allowed a diagnosis in 23 patients (28%) and oriented direct genetic screening identified 21 additional diseases (25.6%). Adult-onset genetic leukoencephalopathies are a rare but probably underestimated entity. Our study confirms the use of a magnetic resonance imaging-based classification with a final diagnosis rate of 64% (98/154) cases.
Prediction of disability progression in multiple sclerosis patients is a critical component of their management. In particular, one challenge is to identify and characterize a patient profile who may ...benefit of efficient treatments. However, it is not yet clear whether a particular relation exists between the brain structure and the disability status.This work aims at producing a fully automatic model for the expanded disability status score estimation, given the brain structural connectivity representation of a multiple sclerosis patient. The task is addressed by first extracting the connectivity graph, obtained by combining brain grey matter parcellation and tractography extracted from Diffusion and T1-weighted Magnetic Resonance (MR) images, and then processing it via a convolutional neural network (CNN) in order to compute the predicted score. Experiments show that the herein proposed approach achieves promising results, thus resulting as an important step forward on the road to better predict the evolution of the disease.
La mesure de la perte du volume cérébral est un marqueur IRM de la neurodégénérescence dans la sclérose en plaques. Les techniques actuelles permettent de quantifier soit directement la perte de ...volume cérébral entre deux examens, soit de la mesurer indirectement à partir du volume cérébral de chaque examen. La fiabilité de ces techniques reste difficile à évaluer en l'absence de gold standard. Ce travail a consisté premièrement, en une étude de reproductibilité réalisée chez 9 patients à partir d'acquisitions semestrielles (3 IRM), sur deux machines différentes et post-traitées par sept algorithmes : BBSI, FreeSurfer, Intégration Jacobienne, KNBSI, un algorithme Segmentation / Classification, SIENA et SIENAX. Deuxièmement, un suivi longitudinal et prospectif a été effectué chez 90 patients SEP. L'étude des variabilités inter-techniques et inter-sites a montré que les techniques de mesures indirectes (Segmentation/Classification, FreeSurfer) et SIENAX fournissaient des pourcentages d'atrophie hétérogènes. A l'inverse, les techniques de mesures directes telles que BBSI, KNBSI, Intégration Jacobienne et à un moindre degré SIENA obtenaient des résultats reproductibles. Toutefois BBSI, KNBSI et l'Intégration Jacobienne obtenaient des pourcentages faibles, suggérant une possible sous-estimation de l'atrophie. L'évaluation de la perte du volume cérébral par Intégration Jacobienne a montré sur 2½ ans de suivi, une atrophie de 1,21% pour les 90 patients et de 1,55%, 1,51%, 0,84%, 1,21% respectivement pour les patients CIS, RR, SP et PP. A l'avenir l'évaluation de la perte de volume cérébral impose des défis d'ordre technique afin d'améliorer la fiabilité des algorithmes actuels.
Deductive formalisms have been strongly developed in recent years; among them, Answer Set Programming (ASP) gained some momentum, and has been lately fruitfully employed in many real-world scenarios. ...Nonetheless, in spite of a large number of success stories in relevant application areas, and even in industrial contexts, deductive reasoning cannot be considered the ultimate, comprehensive solution to AI; indeed, in several contexts, other approaches result to be more useful. Typical Bioinformatics tasks, for instance classification, are currently carried out mostly by Machine Learning (ML) based solutions. In this paper, we focus on the relatively new problem of analyzing the evolution of neurological disorders. In this context, ML approaches already demonstrated to be a viable solution for classification tasks; here, we show how ASP can play a relevant role in the brain evolution simulation task. In particular, we propose a general and extensible framework to support physicians and researchers at understanding the complex mechanisms underlying neurological disorders. The framework relies on a combined use of ML and ASP, and is general enough to be applied in several other application scenarios, which are outlined in the paper.
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