MRI features associated with high likelihood of conversion of radiologically isolated syndrome to multiple sclerosis

The prominence of Oligoclonal Bands for clinical conversion in Radiologically isolated syndrome: 10-year follow-up study in Isfahan, Iran

BACKGROUND

Since data is limited on radiologically isolated syndrome (RIS) subjects in certain regions like the Middle East, we aimed to further explore the replicability and generalizability of previously suggested predictors among a cohort of Iranian RIS subjects and report the long-term clinically definite MS (CDMS) conversion rate in this cohort.

METHODS

We conducted a prospective 10-year cohort on our RIS participants, during which we collected the MRI, paraclinical, and demographic data of the subjects, and identified those who converted to CDMS.

RESULTS

Out of 35 participants, 10 (28.5 %) developed CDMS during an average of 5.58 ± 3.08 years (range: 4 months to 10.33 years). OCB positivity was the only definitive predictor for conversion to CDMS in this cohort (P-value = 0.006), but other previously reported risk factors such as spinal cord lesions or age lacked statistical significance (P-values > 0.05). We also reported the median survival time as 114 months, the proportion surviving after 14 months as 96.9 % ± 3.1 %, and the overall conversion rate as 0.05 cases per year.

CONCLUSION

Our results highlight OCB as an important predictive factor of clinical conversion in RIS. The prominence of OCB suggests a need for routine CSF analysis in RIS subjects and could guide clinicians in deciding which RIS subjects benefit from DMTs.

A multicenter study of radiologically isolated syndrome in children and adolescents: Can we predict the course?

OBJECTIVES

To evaluate clinical characteristics, imaging features and etiological profile of Radiologically Isolated Syndrome (RIS) along with clinical and radiological follow-up.

METHODS

Demographic, clinical and radiological data of patients younger than 18 years fulfilling the criteria for RIS were retrospectively analyzed. RIS was defined by the detection of lesions meeting the revised 2010 McDonald Criteria for dissemination in space on magnetic resonance imaging (MRI) in the absence of any symptoms of demyelinating disease or an alternative cause for the MRI findings.

RESULTS

There were total 69 patients (38 girls, 31 boys). The median age at index MRI was 15.7 years, and median follow-up time was 28 months. The most common reason for neuroimaging was headache (60.9%). A first clinical event occurred with median 11 months in 14/69 (20%) of cases. Those with oligoclonal bands (OCB) in cerebrospinal fluid (CSF) and follow-up longer than 3 years were more likely to experience a clinical event (p<0.05): 25% of those with OCB manifested clinical symptoms within the first year and 33.3% within the first two years compared to 6.3% and 9.4%, respectively in those without OCB. Radiological evolution was not associated with any variables: age, sex, reason for neuroimaging, serum 25-hydroxyvitamin D level, elevated IgG index, OCB positivity, total number and localization of lesions, presence of gadolinium enhancement, achievement of 2005 criteria for DIS and duration of follow-up.

CONCLUSION

Children and adolescents with RIS and CSF OCB should be followed-up for at least 3 years in order to detect any clinical symptoms suggestive of a demyelinating event. Because disease-modifying treatments are not approved in RIS and no consensus report justifies their use especially in pediatric RIS, close follow-up of OCB-positive patients is needed for early recognition of any clinical event and timely initiation of specific treatment.

Magnetic resonance imaging detection of deep gray matter iron deposition in multiple sclerosis: A systematic review

Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease involving immune-mediated damage. Iron deposition in deep gray matter (DGM) structures like the thalamus and basal ganglia have been suggested to play a role in MS pathogenesis. Magnetic Resonance Imaging (MRI) imaging methods like T2 and T2* imaging, susceptibility-weighted imaging, and quantitative susceptibility mapping can track iron deposition storage in the brain primarily from ferritin and hemosiderin (paramagnetic iron storage proteins) with varying levels of tissue contrast and sensitivity. In this systematic review, we evaluated the role of DGM iron deposition as detected by MRI techniques in relation to MS-related neuroinflammation and its potential as a novel therapeutic target. We searched through PubMed, Embase, and Web of Science databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, against predetermined inclusion and exclusion criteria. We included 89 articles (n = 6630 patients), and then grouped them into different categories: i) methodological techniques to measure DGM iron, ii) cross-sectional and group comparison of DGM iron content, iii) longitudinal comparisons of DGM iron, iv) associations between DGM iron and other imaging and neurobiological markers, v) associations with disability, and vi) associations with cognitive impairment. The review revealed that iron deposition in DGM is independent yet concurrent with demyelination, and that these iron deposits contribute to MS-related cognitive impairment and disability. Variability in iron distributions appears to rely on a positive feedback loop between inflammation, and release of iron by oligodendrocytes. DGM iron seems to be a promising prognostic biomarker for MS pathophysiology.

Global transcriptome profiling in peripheral blood mononuclear cells identifies dysregulation of immune processes in individuals with radiologically isolated syndrome

The presence of brain/spinal white matter lesions typical for multiple sclerosis (MS) in asymptomatic individuals is known as 'radiologically isolated syndrome' (RIS). Taking into account that RIS patients are at high risk of MS development, the understanding of mechanisms underlying its pathogenesis is of great importance. In order to investigate RIS-specific transcription signature we performed high-throughput RNA-sequencing in peripheral blood mononuclear cells (PBMCs) of 8 RIS patients and 8 age- and sex-matched healthy controls. We identified 57 differentially expressed genes (DEGs), which levels differed by more than 2 times when comparing RIS patients to healthy controls (FDR p value < 0.05). Gene ontology enrichment analysis in the "biological process" category revealed 16 signaling pathways significantly overrepresented by identified DEGs. The most significant changes in gene expression in PBMCs of RIS patients occur in pathways involved in regulation of the immune response, cytokine and chemokine signaling, cytokine production, and leukocyte migration. In general, analyzing the global transcriptome we demonstrated the dysregulation of immune processes in PBMCs of RIS patients, confirming the current assumption that RIS represents the preclinical stage and/or subclinical form of MS.

Radiologically isolated syndrome: A single-center, retrospective cohort study

BACKGROUND

Radiologically Isolated Syndrome (RIS) likely represents the earliest detectable form of multiple sclerosis (MS). There are recognized risk factors for conversion of RIS to clinically definite central nervous system (CNS) demyelinating disease. We aim to characterize a new clinical cohort with RIS and to analyze previously established risk factors for conversion to clinically definite disease.

METHODS

A medical records search was performed for patients who were diagnosed with RIS by their treating neurologist at our institution in Boston, USA, from January 2005 to April 2020. Demographic data, clinical outcomes, and treatment courses were analyzed. The time to first clinical event representing a demyelinating disease attack or last follow up without clinically definite disease was calculated for each person. Hazard ratios (HRs) for known risk factors for the conversion of RIS to clinically definite disease were calculated using Cox proportional hazards models.

RESULTS

Of 89 patients, the median age at RIS diagnosis was 41.0 years (76% female, 8% with a family history of MS and 16% of any autoimmune disorder, 66% never smokers, 40% BMI >30 kg/m², 45% with spinal cord MRI lesions). Clinically definite disease was observed in 16 patients (18%) during follow-up (median time to first event 3.4 years; median follow-up duration of full cohort 3.8 years). Median EDSS for those who developed clinically definite disease was 1.25 (range: 0-4) at most recent follow up. Of 84 patients with longitudinal brain imaging, 42 (50%) had new demyelinating lesions. Gadolinium-enhancing lesions were seen in 36 patients (43%) at either baseline (n=24) or follow-up (n=12). Most patients had at least one T1-hypointense lesion (n=70, 83%). Five patients underwent ultra-high field MRI (7 Tesla); all were positive for central vein sign, two demonstrated leptomeningeal enhancement, and one was found to have cortical lesions. Out of 30 patients with susceptibility-weighted imaging acquired during routine clinical care, 8 had at least one paramagnetic rim positive lesion. Previously reported risk factors for conversion to MS were not significant: age ≤37 years HR 1.3 (95% confidence interval (CI), 0.47-3.5), male sex 1.5 (95% CI, 0.41-5.2), and spinal cord lesions 1.3 (0.47-3.4). Nearly one-third of RIS patients (n=26) took a disease modifying therapy (DMT) for MS (median total treatment duration on any DMT=2.7 years). The sub-cohort treated with a DMT had a statistically significantly greater number of recognized risk factors for conversion to clinically definite disease compared with the untreated group (p=0.028). Most patients took a DMT for MRI changes demonstrating new demyelinating disease activity (n=16). Dimethyl fumarate (n=9) and glatiramer acetate (n=7) were the most frequently prescribed DMTs. A second-line DMT was started in 10 patients.

CONCLUSION

We characterize a new cohort of RIS patients, demonstrating time to clinically evident demyelinating disease from RIS diagnosis of approximately 3.4 years. Our data suggest that early use of a DMT in RIS may mitigate the impact of recognized risk factors on the occurrence of clinically evident disease and reduce the likelihood of conversion to clinically definite CNS demyelinating disease in high-risk individuals.

RISCOP-Cognitive profile in a Portuguese cohort of radiological isolated syndrome patients: A case-control study

INTRODUCTION

Radiologically isolated syndrome (RIS) refers to the incidental discovery of white matter lesions suggestive of MS, on brain MRI, in asymptomatic patients. Recent studies suggest similar features of cognitive impairment between RIS and MS patients. Also, lower levels of health-related quality of life (QOL) and fatigue are reported in such patients.

AIMS

characterize and compare the cognitive profile of a multicentric Portuguese cohort of RIS patients with a control group.

METHODS

multicentric comparative study of a cohort of adult patients with RIS, and age and gender-matched controls followed in the headache outpatient clinic with prior MRI not fulfilling criteria for RIS diagnosis. We conducted interviews with participants, collected clinical data and applied the BICAMS battery and self-reported questionnaires (HADS, MFIS, MSQOL-54).

RESULTS

we evaluated 31 patients with RIS (median age 46 years, IQR [(Dusankova et al., 2012-52], 72% women) and 19 control individuals (median age 32 years, IQR [(O'Jile et al., 2005-48], 71% women). Prevalence of cognitive impairment did not differ between groups (16% of the RIS and 10% of the controls, p=0.579). We found no differences between groups on the BICAMS tests, although the results of the California Verbal Learning Test (CVLT-II) score presented a trend to significance, with a lower value on the RIS group (53.9 vs. 59.3, p=0.066). There were no significant differences regarding fatigue, QOL, anxiety/depression scores.

CONCLUSION

this is the first study on a Portuguese cohort of RIS patients assessing cognitive profile with BICAMS. A non-neglectable part of our cohort presented cognitive impairment. Our findings add to previous studies in suggesting that a more pronounced impairment of verbal memory and learning, evaluated by CVLT-II, may be present in RIS patients compared to controls. BICAMS should be assessed on future studies with larger cohorts.

Prognostic value of spinal cord MRI in multiple sclerosis patients

Multiple sclerosis [MS] is a common inflammatory, demyelinating and neurodegenerative disease of the central nervous system that affects both the brain and the spinal cord. In clinical practice, spinal cord MRI is performed far less frequently than brain MRI, mainly owing to technical limitations and time constraints. However, improvements of acquisition techniques, combined with a strong diagnosis and prognostic value, suggest an increasing use of spinal cord MRI in the near future. This review summarizes the current data from the literature on the prognostic value of spinal cord MRI in MS patients in the early and later stages of their disease. Both conventional and quantitative MRI techniques are discussed. The prognostic value of spinal cord lesions is clearly established at the onset of disease, underlining the interest of spinal cord conventional MRI at this stage. However, studies are currently lacking to affirm the prognostic role of spinal cord lesions later in the disease, and therefore the added value of regular follow-up with spinal cord MRI in addition to brain MRI. Besides, spinal cord atrophy, as measured by the loss of cervical spinal cord area, is also associated with disability progression, independently of other clinical and MRI factors including spinal cord lesions. Although potentially interesting, this measurement is not currently performed as a routine clinical procedure. Finally, other measures extracted from quantitative MRI have been established as valuable for a better understanding of the physiopathology of MS, but still remain a field of research.

[Radiologically isolated syndrome: prognosis and predictors of conversion to multiple sclerosis]

Increased sensitivity and availability of magnetic resonance imaging (MRI) in neurological routine practice led to the fact that more and more experts began to encounter changes typical for multiple sclerosis (MS) according to MRI in the absence of anamnestic and clinical indications of damage to the central nervous system (CNS). This nosological form has been defined as a radiologically isolated syndrome (RIS). More and more RIS cases convert to MS (up to 30% in the first 5 years after RIS diagnosis). At the moment, there are no biological markers that allow combining RIS and MS into one pathological process and early treatment with disease-modifying drugs (DMT). Prospective studies are actively being conducted to identify demographic, clinical, neuroimaging and biochemical conversion predictors. The identification of the molecular biological RIS features, combining these changes with MS, is an urgent scientific task and will allow timely initiation of therapy of the pathological process already at the subclinical stage.

Radiologically Isolated Syndrome: A Review for Neuroradiologists

Radiologically isolated syndrome refers to an entity in which white matter lesions fulfilling the criteria for multiple sclerosis occur in individuals without a history of a clinical demyelinating attack or alternative etiology. Since its introduction in 2009, the diagnostic criteria of radiologically isolated syndrome and its clinical relevance have been widely debated by neurologists and radiologists. The aim of the present study was to review the following: 1) historical evolution of radiologically isolated syndrome criteria, 2) clinical and imaging findings in adults and children with radiologically isolated syndrome, 3) imaging features of patients with radiologically isolated syndrome at high risk for conversion to MS, and 4) challenges and controversies for work-up, management, and therapeutic interventions of patients with radiologically isolated syndrome.