2021 MAGNIMS-CMSC-NAIMS consensus recommendations on the use of MRI in patients with multiple sclerosis

Diagnosis and Management of Children With Atypical Neuroinflammation

Pediatric neuroimmune disorders comprise a heterogeneous group of immune-mediated CNS inflammatory conditions. Some, such as multiple sclerosis, are well defined by validated diagnostic criteria. Others, such as anti-NMDA receptor encephalitis, can be diagnosed with detection of specific autoantibodies. This review addresses neuroimmune disorders that neither feature a diagnosis-defining autoantibody nor meet criteria for a distinct clinicopathologic entity. A broad differential in these cases should include CNS infection, noninflammatory genetic disorders, toxic exposures, metabolic disturbances, and primary psychiatric disorders. Neuroimmune considerations addressed in this review include seronegative autoimmune encephalitis, seronegative demyelinating disorders such as neuromyelitis optica spectrum disorder, and genetic disorders of immune dysregulation or secondary neuroinflammation. In such cases, we recommend a broad diagnostic workup to support the presence of neuroinflammation, exclude non-neuroimmune disorders, detect autoantibodies and other biomarkers of known diseases, identify any potential genetic drivers of neuroinflammation, and provide case-specific insights into pathophysiologic mechanisms of inappropriate immune pathway activation or dysregulation. This review includes an extensive list of useful diagnostic tests and potential implications thereof, as well as a proposed algorithm for the diagnosis and management of the pediatric patient with atypical neuroimmune disorders. In general, first-line acute treatment of neuroimmune disorders begins with steroids, along with consideration of plasmapheresis or IV immunoglobulin. Selection of second-line or maintenance therapy is challenging without a definite, specific diagnosis and the associated benefit of established evidence-based treatment options. Immunotherapies may be considered based on the suspected mechanism of neuroinflammation and the likelihood of relapse. For example, rituximab may be considered for possible antibody-mediated or B-cell-mediated inflammation while anti-interleukin (IL)-6 agents, anti-IL-1 agents, or JAK inhibitors may be considered for certain cases of cytokine-mediated inflammation or innate immune system dysregulation. Care should be taken to monitor response and disease activity, revisit the differential diagnosis in the case of unexpected findings or poor treatment response, and weigh the risks of immunotherapy with the benefits of empiric treatment. Over time, further advancements in biomarker identification and omics research may define specific new clinicopathologic diagnoses and thus obviate the need for "n of 1" approaches to what are currently heterogeneous groups of atypical seronegative neuroimmune disorders.

Imaging in France: 2024 Update

Radiology in France has made major advances in recent years through innovations in research and clinical practice. French institutions have developed innovative imaging techniques and artificial intelligence applications in the field of diagnostic imaging and interventional radiology. These include, but are not limited to, a more precise diagnosis of cancer and other diseases, research in dual-energy and photon-counting computed tomography, new applications of artificial intelligence, and advanced treatments in the field of interventional radiology. This article aims to explore the major research initiatives and technological advances that are shaping the landscape of radiology in France. By highlighting key contributions in diagnostic imaging, artificial intelligence, and interventional radiology, we provide a comprehensive overview of how these innovations are improving patient outcomes, enhancing diagnostic accuracy, and expanding the possibilities for minimally invasive therapies. As the field continues to evolve, France's position at the forefront of radiological research ensures that these innovations will play a central role in addressing current healthcare challenges and improving patient care on a global scale.

Frequency and potential risk factors associated with the development of asymptomatic T2 hyperintense cervical spine lesions on MRI in patients with relapsing-remitting multiple sclerosis

BACKGROUND

Spinal cord (SC) imaging is less routinely used for monitoring disease activity in patients with multiple sclerosis (MS), and the frequency of clinically silent breakthrough SC disease remains unclear.

OBJECTIVE

The objective was to determine the frequency of asymptomatic T2 hyperintense cervical SC (c-SC) lesions in patients with relapsing-remitting MS (RRMS) and identify associated risk factors.

METHODS

We included RRMS patients aged 18-65 years followed at the Johns Hopkins MS Center (2014-2019), with up to four brain and c-SC magnetic resonance imaging (MRI) scans considered per patient. New asymptomatic lesions were identified as hyperintense T2 lesions on MRI during routine surveillance. Univariate and multivariate logistic regression identified factors associated with developing asymptomatic lesions on the first scan, and a generalized estimating equations model assessed factors across successive scans.

RESULTS

Among 869 patients included, the proportion of asymptomatic lesions identified ranged from 4.8% to 12.1% across scans. Roughly half of those with c-SC lesions also showed new brain lesions. Patients receiving higher-efficacy therapies were more likely to have an asymptomatic lesion detected (odds ratio (OR) = 1.48, 95% confidence interval (CI) = 1.16-1.88, p = 0.001), as were Black/African American individuals (OR = 1.64, 95% CI = 1.23-2.18, p = 0.001).

CONCLUSION

These findings suggest a limited but important role for c-SC imaging, especially for Black/African Americans who may benefit from routine surveillance.

Sensitivity of multi-parametric quantitative magnetic resonance imaging for multiple sclerosis pathology

BACKGROUND

In recent years, quantitative magnetic resonance imaging (MRI) made progress towards clinical applicability mainly through advances in acceleration techniques. In patients with multiple sclerosis (MS), objective quantitative MRI-based characterization of subtle pathological alterations in lesions, perilesion (PL), as well as normal-appearing (NA) white matter (NAWM) and grey matter (NAGM) would revolutionize clinical assessment. While numerous quantitative techniques have been applied in studies of MS patients, their diagnostic significance especially for individual patients with relatively short disease duration is unclear. Therefore, we investigated the sensitivity of several quantitative MRI parameters to focal and diffuse MS pathology in a clinical feasibility study with a small sample size.

METHODS

In 13 MS patients with a mean disease duration of 8 years and a mean EDSS of 1.1 as well as 14 healthy age-matched controls (HC), we acquired nine (semi-)quantitative magnetic resonance (MR) biomarkers, namely myelin water fraction (MWF), magnetization transfer (MT) saturation (MTsat), inhomogeneous MT ratio (ihMTR), quantitative longitudinal relaxation time (qT1), intrinsic (qT2) and effective (qT2*) quantitative transverse relaxation times, proton density (PD), quantitative susceptibility mapping (QSM), and the ratio between T1-weighted and T2-weighted images (T1w/T2w). Four volumes of interest were automatically defined (NA/HC grey matter (GM), NA/HC white matter (WM), lesion, and PL), and biomarker values were analyzed between groups and tissue types.

RESULTS

For all nine assessed biomarkers, mean values per patient were significantly different between lesion, PL, and NAWM (p <  0.05, FDR corrected). The lesion values of qT1, qT2, qT2 * , PD, and QSM were rather inhomogeneous. Furthermore, MWF, MTsat, and ihMTR were sensitive to diffuse WM pathology in MS with the largest absolute differences between NAWM and HCWM medians, albeit not statistically significant after correction for multiple testing.

DISCUSSION

In our study, we successfully compared nine different quantitative MR parameters within the same subjects for tissue characterization of MS. Our study adds relevant aspects to the current debate on different sensitivities of various quantitative MR biomarkers to MS pathology. While all investigated MR biomarkers allowed characterizing lesions in individual patients, a separation of NAWM and HCWM could be most promising with the myelin-sensitive measures MWF, MTsat, and ihMTR.

User requirements for quantitative radiological reports in multiple sclerosis

OBJECTIVES

Quantitative radiological reports (QReports) can enhance clinical management of multiple sclerosis (MS) by including quantitative data from MRI scans. However, the lack of consensus on the specific information to include, on and clinicians' preferences, hinders the adoption of these imaging analysis tools. This study aims to facilitate the clinical implementation of QReports by determining clinicians' requirements regarding their use in MS management.

MATERIALS AND METHODS

A four-phase Delphi panel approach was employed, involving neurologists and (neuro)radiologists across Europe. Initial interviews with experts helped develop a questionnaire addressing various QReport aspects. This questionnaire underwent refinement based on feedback and was distributed through the MAGNIMS network. A second questionnaire, incorporating additional questions, was circulated following a plenary discussion at the MAGNIMS workshop in Milan in November 2023. Responses from both questionnaire iterations were collected and analyzed, with adjustments made based on participant feedback.

RESULTS

The study achieved a 49.6% response rate, involving 78 respondents. Key preferences and barriers to QReport adoption were identified, highlighting the importance of integration into clinical workflows, cost-effectiveness, educational support for interpretation, and validation standards. Strong consensus emerged on including detailed lesion information and specific brain and spinal cord volume measurements. Concerns regarding report generation time, data protection, and reliability were also raised.

CONCLUSION

While QReports show potential for improving MS management, incorporation of the key metrics and addressing the identified barriers related to cost, validation, integration, and clinician education is crucial for practical implementation. These recommendations for developers to refine QReports could enhance their utility and adoption in clinical practice.

KEY POINTS

Question A lack of consensus on essential features for quantitative magnetic resonance imaging reports limits their integration into multiple sclerosis management. Findings This study identified key preferences, including detailed lesion information, specific brain and spinal cord measurements, and rigorous validation for effective quantitative reports. Clinical relevance This study identified essential features and barriers for implementing quantitative radiological reports in multiple sclerosis management, aiming to enhance clinical workflows, improve disease monitoring, and ultimately provide better, data-driven care for patients through tailored imaging solutions.

Clinical and MRI features contributing to the clinico-radiological dissociation in a large cohort of people with multiple sclerosis

BACKGROUND

People with Multiple Sclerosis (PwMS) often show a mismatch between disability and T2-hyperintense white matter (WM) lesion volume (LV), that in general is referred to as the clinico-radiological paradox.

OBJECTIVES

This study aimed to understand how an extensive clinical, neuropsychological, and MRI analysis could better elucidate the clinico-radiological dissociation in a large cohort of PwMS.

METHODS

Clinical scores, such as Expanded Disability Status Scale (EDSS), 9 Hole Peg Test (9HPT), 25-foot Walking Test (25-FWT), Paced Auditory Serial Addition Test at 3 s (PASAT3), Symbol digit Modalities Test (SDMT), demographics, and 3 T-MRI of 717 PwMS and 284 healthy subjects (HS) were downloaded from the INNI database. Considering medians of LV and EDSS scores, PwMS were divided into four groups: low LV and disability (LL/LD); high LV and low disability (HL/LD); low LV and high disability (LL/HD); high LV and disability (HL/HD). MRI measures included: volumes of gray matter (GM), WM, cerebellum, basal ganglia and thalamus, spinal cord (SC) area, and functional connectivity of resting-state networks.

RESULTS

The clinico-radiological dissociation involved 36% of our sample. HL/LD showed worse SDMT scores and lower global and deep GM volumes than HS and LL/LD. LL/HD showed lower GM, thalamus, and cerebellum volumes, and SC area than HS, and lower SC area than LL/LD.

CONCLUSIONS

A more extensive clinical assessment, including cognitive tests, and MRI evaluation including deep GM and SC, could better describe the real status of the disease and help clinicians in early and tailored treatment in PwMS.

Neurodegeneration and Demyelination in the Multiple Sclerosis Spinal Cord: Clinical, Pathological, and 7T MRI Perspectives

BACKGROUND AND OBJECTIVES

Key findings in people with multiple sclerosis (MS) with progressive motor disability are spinal cord (SC) atrophy signifying irreversible axonal loss and SC demyelinated lesions. This study aimed to identify neurodegenerative changes and assess the clinical impact and pathologic characteristics of SC lesions.

METHODS

A cross-sectional study was performed using postmortem cervical cord segments from the Cleveland Clinic MS Rapid Autopsy Program. Inclusion included proximity to our center, absence of transmissible infections, and lack of prolonged hypoxia. In situ MRIs were performed before tissue removal and fixation followed by 7T MRI and immunohistochemistry. Quantitative T2* relaxation times were correlated with myelin, axons, and activated microglia/macrophages (major histocompatibility complex II [MHCII]) using Tukey comparison of means and a linear mixed-effects model; T2* was correlated with clinical disease characteristics using Wilcoxon rank sum.

RESULTS

The study included 40 MS cases (median age 58, female 55%) and 9 controls (median age 69, female 89%). A T2* threshold reliably discriminated demyelination (accuracy 89.7%, sensitivity 95.5%, and specificity 87.0%). Myelin content (95% CI -0.82 to -0.58, estimate -0.70) was the only significant predictor of T2*. T2* hyperintensities within the segments ranged from 0% to 100% (median 33.6, interquartile range 12.9-64.3) with only 57.1% demyelinated. T2*-hyperintense/myelinated regions had increased T2* relaxation time (19.2 ms, 95% CI 9.97-28.4), reduced myelin content (-8.3%, 95% CI -12.1 to -4.4), increased MHCII (3.6%, 95% CI 0.45-6.7), reduced axonal counts (-349.8, 95% CI -565.4 to -134.1), and increased axonal area (2.0 µm2, 95% CI 1.0-3.1) compared with normal-appearing MRI regions. These regions occurred adjacent to T2*-hyperintense/demyelinated lesions (periplaque) or along tracts (tract-based). 7T postmortem T2* hyperintensities were subtle on clinical 1.5T axial T2, and only 43% were detected sagittally. T2*-hyperintense/demyelinated lesions correlated with Expanded Disability Status Scale (EDSS) (rho = 0.61, p < 0.0001) and upper cervical cord area (rho = -0.64, p < 0.0001) while T2*-hyperintense/myelinated regions did not.

DISCUSSION

Thresholding 7T T2* postmortem MRI can effectively discriminate demyelinated lesions which correlate with clinical disability and cord atrophy. T2*-hyperintense/myelinated regions exhibit myelin and axonal pathology in periplaque or tract-based distributions suggestive of neurodegeneration. Limitations include sampling of 2-cm of SC across participants making conclusions about proximal and distal pathology difficult.

MOG35 - 55-induced EAE model of optic nerve inflammation compared to MS, MOGAD and NMOSD related subtypes of human optic neuritis

Optic neuritis (ON), or inflammation of the optic nerve, is a common presenting symptom of demyelinating neuroinflammatory conditions that result in significant, subacute vision loss. Given its association with visual impairment and varying extent of visual recovery, ON has been recognized as a significant health burden with a need for new therapeutic strategies to improve long-term visual outcomes. Among the resources utilized to study ON, animal models have emerged as powerful tools to examine the underlying pathophysiology and the effectiveness of proposed therapies. In the current review, we discuss the functional and structural phenotypes related to ON in currently used mouse models, and summarize how the pathophysiology and visual phenotype of the myelin oligodendrocyte glycoprotein 35-55 (MOG35 - 55) experimental autoimmune encephalomyelitis (EAE) mouse model recapitulates clinical features of multiple sclerosis (MS), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and neuromyelitis optica spectrum disorder (NMOSD). The location of ON and the amount of visual recovery in the EAE model most closely resembles MS and NMOSD. However, we propose that the MOG35 - 55-induced EAE model of ON is primarily a MOGAD model given its similarity in pathophysiology, spinal cord demyelination pattern, and the degree of vision loss, retinal nerve fiber layer (RNFL) swelling, and disc edema. Overall, the MOG35 - 55-induced EAE animal model demonstrates overlapping features of autoimmune demyelinating conditions and serves as a comprehensive tool to further our understanding of visual impairment in all three conditions.

T1 Relaxation-Enhanced Steady-State Acquisition With Radial k-Space Sampling: A Novel Family of Pulse Sequences for Motion-Robust Volumetric T1-Weighted MRI With Improved Lesion Conspicuity

OBJECTIVES

Magnetization-prepared rapid gradient-echo (MP-RAGE) sequences are routinely acquired for brain exams, providing high conspicuity for enhancing lesions. Vessels, however, also appear bright, which can complicate the detection of small lesions. T1RESS (T1 relaxation-enhanced steady-state) sequences have been proposed as an alternative to MP-RAGE, offering improved lesion conspicuity and suppression of blood vessels. This work aims to evaluate the performance of radial T1RESS variants for motion-robust contrast-enhanced brain MRI.

MATERIALS AND METHODS

Radial stack-of-stars sampling was implemented for steady-state free-precession-based rapid T1RESS acquisition with saturation recovery preparation. Three variants were developed using a balanced steady-state free-precession readout (bT1RESS), an unbalanced fast imaging steady precession (FISP) readout (uT1RESS-FISP), and an unbalanced reversed FISP readout (uT1RESS-PSIF). Image contrast was evaluated in numerical simulations and phantom experiments. The motion robustness of radial T1RESS was demonstrated with a motion phantom. Four patients and six healthy volunteers were scanned at 3 T and 0.55 T. Extensions were developed combining T1RESS with GRASP for dynamic imaging, with GRAPPA for accelerated scans, and with Dixon for fat/water separation.

RESULTS

In simulations and phantom scans, uT1RESS-FISP provided higher signal intensity for regions with lower T1 values (<500 ms) compared with MP-RAGE. In motion experiments, radial uT1RESS-FISP showed fewer artifacts than MP-RAGE and Cartesian uT1RESS-FISP. In patients, both unbalanced uT1RESS variants provided higher lesion conspicuity than MP-RAGE. Blood vessels appeared bright with MP-RAGE, gray with uT1RESS-FISP, and dark with uT1RESS-PSIF. At 0.55 T, bT1RESS provided high signal-to-noise ratio T1-weighted images without banding artifacts. Lastly, dynamic T1RESS images with a temporal resolution of 10.14 seconds/frame were generated using the GRASP algorithm.

CONCLUSIONS

Radial T1RESS sequences offer improved lesion conspicuity and motion robustness and enable dynamic imaging for contrast-enhanced brain MRI. Both uT1RESS variants showed higher tumor-to-brain contrast than MP-RAGE and may find application as alternative techniques for imaging uncooperative patients with small brain lesions.

Limited added value of systematic spinal cord MRI vs brain MRI alone to classify patients with MS as active or inactive during follow-up

BACKGROUND

The utility of systematic spinal cord (SC) MRI for monitoring disease activity after a multiple sclerosis (MS) diagnosis remains a topic of debate.

OBJECTIVES

To evaluate the frequency of disease activity when considering brain MRI alone versus both brain and SC MRI and to identify factors associated with the occurrence of new SC lesions.

METHODS

We conducted a retrospective analysis of clinical and imaging data prospectively collected over 5 years as part of the EMISEP cohort study. A total of 221 intervals (with both brain and spinal cord MRI scans available at 2 consecutive time-points) from 68 patients were analysed. For each interval, brain (3D Fluid-Attenuated Inversion Recovery (FLAIR, axial T2 and axial PD) and SC MRI (sagittal T2 and phase-sensitive inversion recovery, axial T2*w and 3D T1) were reviewed to detect new lesions. Each interval was classified as symptomatic (with relapse) or asymptomatic. The baseline brain and SC lesion numbers were computed.

RESULTS

SC MRI activity without clinical relapse and/or brain MRI activity was rare (4 out of 221 intervals, 2%). The occurrence of a new SC lesion was associated with the number of brain lesions at baseline (OR = 1.002 [1.000; 1.0004], p = 0.015) and the occurrence of a new brain lesion during the interval (OR = 1.170 [1.041; 1.314], p = 0.009), but not with the baseline SC lesion number (p = 0.6).

CONCLUSION

These findings support the current guidelines recommending routine disease monitoring with brain MRI alone, even in patients with a high SC lesion load.

Evaluation of a deep learning segmentation tool to help detect spinal cord lesions from combined T2 and STIR acquisitions in people with multiple sclerosis

OBJECTIVE

To develop a deep learning (DL) model for the detection of spinal cord (SC) multiple sclerosis (MS) lesions from both sagittal T2 and short tau inversion recovery (STIR) sequences and to investigate whether such a model could improve the performance of clinicians in detecting SC lesions.

MATERIALS AND METHODS

A DL tool was developed based on SC sagittal T2 and STIR acquisitions from the imaging database of the French MS registry (OFSEP), including retrospective data from 40 different scanners. A multi-reader study based on retrospective data was performed between December 2023 and June 2024 to compare the performance of 20 clinicians in interpreting upper and lower SC acquisitions with and without the use of the tool. A ground truth was established by three experts. Sensitivity, precision, and inter-reader variability were evaluated.

RESULTS

We included 50 patients (39 females, median age: 41 years [range: 15-67]) with SC MRI acquired between February 2017 and December 2022. When reading with the tool, the clinicians' mean sensitivity to detect SC lesions improved (from 74.3% [95% CI = 67.8-80.6%] to 79.2% [95% CI: 73.5-85.0%]; p < 0.0001), with no evidence of difference in the mean precision: (69.0% [95% CI: 62.8-75.2%] vs 70.1% [95% CI: 64.3-75.9%]; p = 0.08). Inter-reader variability in lesion detection was slightly improved with the tool (Light's kappa = 0.55 vs 0.60), but without statistical difference (p = 0.056).

CONCLUSION

The use of an automatic tool can help clinicians detect SC lesions in pwMS by increasing their sensitivity.

KEY POINTS

Question No tool to help detect MS SC lesions is used in clinical practice despite their frequency and prognostic value. Findings This DL-based tool led to improvement in clinicians' sensitivity in detecting SC lesions from both sagittal T2 and STIR sequences, without decreasing precision. Clinical relevance Our study indicated the potential of a DL-based tool to assist clinicians in the challenging task of detecting SC lesions in people with MS on a combination of sequences commonly acquired in clinical practice.

Super-Resolution in Clinically Available Spinal Cord MRIs Enables Automated Atrophy Analysis

BACKGROUND AND PURPOSE

Measurement of the mean upper cervical cord area (MUCCA) is an important biomarker in the study of neurodegeneration. However, dedicated high-resolution (HR) scans of the cervical spinal cord are rare in standard-of-care imaging due to timing and clinical usability. Most clinical cervical spinal cord imaging is sagittally acquired in 2D with thick slices and anisotropic voxels. As a solution, previous work describes HR T1-weighted brain imaging for measuring the upper cord area, but this is still not common in clinical care.

MATERIALS AND METHODS

We propose using a zero-shot super-resolution technique, synthetic multi-orientation resolution enhancement (SMORE), already validated in the brain, to enhance the resolution of 2D-acquired scans for upper cord area calculations. To incorporate super-resolution in spinal cord analysis, we validate SMORE against HR research imaging and in a real-world longitudinal data analysis.

RESULTS

Super-resolved (SR) images reconstructed by using SMORE showed significantly greater similarity to the ground truth than low-resolution (LR) images across all tested resolutions (P < .001 for all resolutions in peak signal-to-noise ratio [PSNR] and mean structural similarity [MSSIM]). MUCCA results from SR scans demonstrate excellent correlation with HR scans (r > 0.973 for all resolutions) compared with LR scans. Additionally, SR scans are consistent between resolutions (r > 0.969), an essential factor in longitudinal analysis. Compared with clinical outcomes such as walking speed or disease severity, MUCCA values from LR scans have significantly lower correlations than those from HR scans. SR results have no significant difference. In a longitudinal real-world data set, we show that these SR volumes can be used in conjunction with T1-weighted brain scans to show a significant rate of atrophy (-0.790, P = .020 versus -0.438, P = .301 with LR).

CONCLUSIONS

Super-resolution is a valuable tool for enabling large-scale studies of cord atrophy, as LR images acquired in clinical practice are common and available.

Real-world evidence of ocrelizumab in Chilean patients with multiple sclerosis

BACKGROUND

Real-world studies are needed to expand our knowledge concerning populations underrepresented in clinical trials.

OBJECTIVE

This study aimed to evaluate the safety and effectiveness of ocrelizumab in Hispanic/Latino people with multiple sclerosis (pwMS).

METHODS

Prospective longitudinal observational study including pwMS who received at least one dose of ocrelizumab between June 2018 and October 2023.

RESULTS

A total of 305 pwMS (223 relapsing-remitting MS (RRMS), 29 secondary progressive MS (SPMS), and 53 primary progressive MS (PPMS)), 67% female, mean age 38.7, mean disease duration 7 years, and median Expanded Disability Status Scale (EDSS) 2.0 (range 0-7). Median follow-up under ocrelizumab 29.5 (range 6-65) months. Only 1 patient had a relapse, 12-week-confirmed disability worsening was observed in 12.4% of the full cohort. Survival analysis showed higher risk of 12-week-confirmed disability worsening in SPMS compared with RRMS and PPMS (p = 0.0009). Magnetic resonance imaging (MRI) activity was significantly reduced from baseline across all disease phenotypes. Serious infections were observed in 4.6%, and two patients died during follow-up (one serious COVID-19 and one metastatic cancer). Notably, 22 pregnancies were reported, with 11 newborns and 6 pregnancies still on course.

CONCLUSION

This study supports the effectiveness of ocrelizumab in a real-world cohort of individuals from traditionally underrepresented groups, such as the Latin American population, with a consistent safety profile in patients receiving care at a specialized MS Unit.

Longitudinal Multiparametric Quantitative MRI Evaluation of Acute and Chronic Multiple Sclerosis Paramagnetic Rim Lesions

BACKGROUND

Multiple sclerosis (MS) paramagnetic rim lesions (PRLs) are markers of chronic active biology and exhibit complex iron and myelin changes that may complicate quantification when using conventional MRI approaches.

PURPOSE

To conduct a multiparametric MRI analysis of PRLs.

STUDY TYPE

Retrospective/longitudinal.

SUBJECTS

Ninety-five progressive MS subjects with at least one persistent PRL who were enrolled in the CONSONANCE trial.

FIELD STRENGTH/SEQUENCE

3-T/Susceptibility-weighted, T1-weighted, T2-weighted, and fluid-attenuated inversion recovery.

ASSESSMENT

Acute/chronic PRLs and non-PRLs were measured at screening, 24, 48, and 96 weeks using quantitative magnetic susceptibility (QS), R2*, and standardized T1w/T2w ratio (sT1w/T2w). PRL analyses were performed for whole lesion, core, and rim. The correlations between PRL core and rim sT1w/T2w, QS, and R2* were assessed.

STATISTICAL TESTS

Linear mixed models. A P-value <0.05 was considered significant.

RESULTS

There was a significant decrease in sT1w/T2w (-0.24 ± -5.3 × 10-3) and R2* (-3.6 ± 2.2 Hz) but a significant increase in QS (+21 ± 1.3 ppb) using whole-lesion analysis of chronic PRLs compared to non-PRLs at screening. Tissue damage accumulated at the 96-week time point was more evident in acute/chronic PRLs compared to acute/chronic non-PRLs (ΔsT1w/T2w = -0.21/-0.24 ± 0.033/0.0053; ΔR2* = -4.4/-3.6 ± 1.4/2.2 Hz). New, acute PRL sT1w/T2w significantly increased in lesion core (+4.3 × 10-3 ± 1.2 × 10-4) and rim (+5.6 × 10-3 ± 1.2 × 10-4) 24 weeks post lesion inception, suggestive of partial recovery. Chronic PRLs, contrastingly, showed significant decreases in sT1w/T2w over the initial 24 weeks for both core (-2.1 × 10-4 ± 2.0 × 10-5) and rim (-2.4 × 10-4 ± 2.0 × 10-5), indicative of irreversible tissue damage. Significant positive correlations between PRL core and rim sT1w/T2w (R2 = 0.53), R2* (R2 = 0.69) and QS (R2 = 0.52) were observed.

DATA CONCLUSION

Multiparametric assessment of PRLs has the potential to be a valuable tool for assessing complex iron and myelin changes in chronic active PRLs of progressive MS patients.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 3.

Radiological features in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease-diagnostic criteria and lesion dynamics

The spectrum of acquired pediatric demyelinating syndromes has been expanding over the past few years, to include myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), as a distinct neuroimmune entity, in addition to pediatric-onset multiple sclerosis (POMS) and aquaporin 4-IgG-seropositive neuromyelitis optica spectrum disorder (AQP4+NMOSD). The 2023 MOGAD diagnostic criteria require supporting clinical or magnetic resonance imaging (MRI) features in patients with low positive myelin oligodendrocyte glycoprotein IgG titers or when the titers are not available, highlighting the diagnostic role of imaging in MOGAD. In this review, we summarize the key diagnostic features in MOGAD, in comparison to POMS and AQP4+NMOSD. We describe the lesion dynamics both during attack and over time. Finally, we propose a guideline on timing of imaging in clinical practice.

Non-contrast magnetic resonance evaluation of active multiple sclerosis lesions: Emerging role of quantitative synthetic magnetic resonance imaging

PurposeThe current study aims to explore the utility of novel synthetic MRI-derived quantitative parameters including myelin-correlated volume (MyC) in identifying active MS lesions without injecting gadolinium contrast.Methods43 MS patients underwent institutional MS protocol including 3D FLAIR and post-contrast 3D T1VIBE sequence on a 1.5 T MR Scanner in addition to synthetic MRI sequence. MS plaques were categorised into enhancing (C) and non-enhancing (N) lesions. They were also sub-categorised based on location into periventricular WM lesions (P), deep WM lesions (D), infratentorial lesions (I) and cortical-juxtacortical (C) lesions. ROIs were placed on Synthetic FLAIR images in MS lesions and quantitative parameters of R1, R2, PD and myelin-correlated volume (MyC) obtained. Sensitivity and specificity for various cut-off values to differentiate enhancing from non-enhancing multiple sclerosis lesions were calculated by performing ROC curve analysis and logistic regression analysis.ResultsContrast enhancing lesions demonstrated significantly higher mean R1, R2 values and lower mean PD values in comparison to non-enhancing lesions (p < 0.05) but with limited specificity. Region-wise analysis revealed high AUC values for mean R1 and R2 at cortical-juxtacortical lesions (p < 0.001) followed by periventricular lesions (p < 0.003) for differentiating enhancing from non-enhancing lesions with no significant contribution from MyC and PD values.ConclusionSynthetic MRI-derived quantitative parameters of mean R1, R2, MyC and PD hold value in differentiating contrast enhancing and non-enhancing MS lesions without administering gadolinium-based contrast agent. However, the current study did not achieve significant specificity for establishing the same.

Fluid-based biomarkers for neurodegenerative diseases

Neurodegenerative diseases, such as Alzheimer's Disease (AD), Multiple Sclerosis (MS), Parkinson's Disease (PD), and Amyotrophic Lateral Sclerosis (ALS) are increasingly prevalent as global populations age. Fluid biomarkers, derived from cerebrospinal fluid (CSF), blood, saliva, urine, and exosomes, offer a promising solution for early diagnosis, prognosis, and disease monitoring. These biomarkers can reflect critical pathological processes like amyloid-beta (Aβ) deposition, tau protein hyperphosphorylation, α-syn misfolding, TDP-43 mislocalization and aggregation, and neuronal damage, enabling detection long before clinical symptoms emerge. Recent advances in blood-based biomarkers, particularly plasma Aβ, phosphorylated tau, and TDP-43, have shown diagnostic accuracy equivalent to CSF biomarkers, offering more accessible testing options. This review discusses the current challenges in fluid biomarker research, including variability, standardization, and sensitivity issues, and explores how combining multiple biomarkers with clinical symptoms improves diagnostic reliability. Ethical considerations, future directions involving extracellular vehicles (EVs), and the integration of artificial intelligence (AI) are also highlighted. Continued research efforts will be key to overcoming these obstacles, enabling fluid biomarkers to become crucial tools in personalized medicine for neurodegenerative diseases.

Current challenges in secondary progressive multiple sclerosis: diagnosis, activity detection and treatment

Approximately 50% diagnosed with relapsing-remitting multiple sclerosis (RRMS) transition to secondary progressive multiple sclerosis (SPMS) within 20 years following disease onset. However, early diagnosis of SPMS and effective treatment remain important clinical challenges. The lack of established diagnostic criteria often leads to delays in identifying SPMS. Also, there are limited disease-modifying therapies (DMTs) available for progressive forms of MS, and these therapies require evidence of disease activity to be initiated. This review examines the challenges in diagnosing SPMS at an early stage and summarizes the current and potential use of biomarkers of disease progression in clinical practice. We also discuss the difficulties in initiating the DMTs indicated for active SPMS (aSPMS), particularly in patients already undergoing treatment with DMTs that suppress disease activity, which may mask the presence of inflammatory activity required for the therapy switch. The article also addresses the DMTs available for both active and non-active SPMS, along with the clinical trials that supported the approval of DMTs indicated for aSPMS or relapsing MS in Europe, which includes aSPMS. We also offer insights on when discontinuing these treatments may be appropriate.

Distinct clinical, imaging, and cerebrospinal fluid profiles in people with late-onset multiple sclerosis

INTRODUCTION

Late-onset multiple sclerosis (LOMS), defined as onset after age 50, poses unique diagnostic challenges due to clinical and radiological differences from early-onset multiple sclerosis (EOMS), which typically manifests in adults between 20 and 40 years of age. Limited research on these differences hampers accurate diagnosis of LOMS. This study aims to bridge this gap by comparing clinical presentation, imaging, and cerebrospinal fluid (CSF) findings in LOMS and EOMS patients.

METHODS

We retrospectively analyzed clinical, MRI, and CSF data from 148 LOMS patients treated in the neuroimmunology outpatient clinic of a Swiss tertiary referral center between 2013 and 2023. A control group of 148 EOMS patients, matched by year of diagnosis, was included for comparison.

RESULTS

LOMS patients, with a median onset age of 53 years (interquartile range (IQR) 51-58 years), more commonly presented with motor or multiple symptoms and a primary progressive multiple sclerosis subtype (p < 0.001). They were also more likely than EOMS patients (median onset age 28 years, IQR 24-33 years) to report cognitive impairment and fatigue at disease onset (p < 0.001). MRI analysis showed that LOMS patients had a significantly higher T2-lesion load (p = 0.026) but fewer Gadolinium-enhancing lesions at diagnosis (p < 0.001). The percentage of patients with CSF-specific oligoclonal bands was comparable between groups, whereas CSF pleocytosis was more common in EOMS patients (p < 0.001). Importantly, we noticed a significant delay in diagnosing multiple sclerosis in older adults likely due to misdiagnosis or difficulties in timely recognition.

DISCUSSION

LOMS represents a subgroup of multiple sclerosis with unique clinical and radiological characteristics compared to EOMS. The higher T2-lesion burden and fewer Gadolinium-enhancing lesions in LOMS can pose diagnostic challenges. Recognizing these differences may enhance diagnostic accuracy and guide more effective management strategies for LOMS.

Lesion assessment in multiple sclerosis: a comparison between synthetic and conventional fluid-attenuated inversion recovery imaging

Background and purpose

Magnetic resonance imaging (MRI)-based lesion quantification is essential for the diagnosis of and prognosis in multiple sclerosis (MS). This study compares an established software's performance for automated volumetric and numerical segmentation of MS brain lesions using synthetic T2-weighted fluid-attenuated inversion recovery (FLAIR) MRI, based on a multi-dynamic, multi-echo sequence (MDME), vs. conventional FLAIR imaging.

Methods

To ensure comparability, 3D FLAIR images were resampled to 4 mm axial slices to match the synthetic images' slice thickness. Lesion segmentation was performed using the Lesion Prediction Algorithm within the Lesion Segmentation Toolbox. For the assessment of spatial differences between lesion segmentations from both sequences, all lesion masks were registered to a brain template in the standard space. Spatial agreement between the two sequences was evaluated by calculating Sørensen-Dice coefficients (SDC) of the segmented and registered lesion masks. Additionally, average lesion masks for both synthetic and conventional FLAIR were created and displayed as overlays on a brain template to visualize segmentation differences.

Results

Both total lesion volume (TLV) and total lesion number (TLN) were significantly higher for synthetic MRI (11.0 ± 12.8 mL, 19.5 ± 12.1 lesions) than for conventional images (6.1 ± 8.5 mL, 17.9 ± 12.5 lesions). Bland-Altman plot analysis showed minimal TLV differences between synthetic and conventional FLAIR in patients with low overall lesion loads. The intraclass coefficient (ICC) indicated excellent agreement between both measurements, with values of 0.88 for TLV and 0.89 for TLN. The mean SDC was 0.47 ± 0.15.

Conclusion

Despite some limitations, synthetic FLAIR imaging holds promise as an alternative to conventional FLAIR for assessing MS lesions, especially in patients with low lesion load. However, further refinement is needed to reduce unwanted artifacts that may affect image quality.

A novel HMBS gene mutation in acute intermittent porphyria: a case report of abdominal pain, seizures, and reversible neuroimaging findings

Background

Acute intermittent porphyria (AIP) is a rare metabolic disorder resulting from defects in the heme biosynthesis pathway, often presenting with non-specific symptoms such as abdominal pain, seizures, and neuropsychiatric disturbances. Diagnosis is challenging due to the overlap of symptoms with other conditions, and early recognition is critical for effective treatment.

Case Presentation

A 24-year-old female presented with a 6-day history of persistent lower abdominal pain and generalized tonic-clonic seizures, following the consumption of seafood. Neuroimaging revealed white matter hyperintensities, and urine analysis showed dark red discoloration, suggestive of porphyria. Genetic testing confirmed a novel c.499-1_514del mutation in the HMBS gene, diagnosing AIP. The patient was treated with intravenous glucose, heme arginate, and anticonvulsants. Symptom resolution was noted within days, and follow-up MRI showed significant improvement.

Conclusion

This case underscores the importance of early diagnosis and management in AIP. Genetic testing plays a crucial role in confirming the diagnosis, especially in atypical cases. Timely intervention with glucose and heme arginate, combined with supportive care, led to rapid symptom resolution, reinforcing the reversibility of AIP-associated neuroimaging changes. Clinicians should maintain a high index of suspicion for AIP in patients with unexplained abdominal and neurological symptoms to prevent long-term complications.

Scoping review: The effects of diet, physical activity and sleep on motor and physical fatigue in people with multiple sclerosis

Physical and motor fatigue are debilitating symptoms common in multiple sclerosis (MS). Lifestyle interventions may be effective in managing MS-related fatigue. This scoping review aims to: (i) identify and summarise lifestyle interventions including those focused on diet, physical activity, and sleep, or multicomponent interventions for physical and motor fatigue management in MS; and (ii) provide recommendations for future research in this area. Database searches of MEDLINE (Ovid), Cochrane (Cochrane Library), Scopus (Elsevier), CINAHL (EBSCOhost), and Embase (Ovid) were conducted. To be included in this scoping review, studies were to be published in a peer reviewed scientific journal, focused on a non-pharmacological lifestyle intervention (physical activity, exercise, sleep, diet, or a combination), and written in English. Forty-one studies were included for analysis. Included participants were predominantly female, living with relapsing-remitting MS, with a median age of 48 years. The design of the studies comprised mainly of randomised control trials and pilot/feasibility studies. All included studies incorporated a physical activity intervention, with most examining aerobic/endurance exercise. Most studies reported an effect on improving physical/motor fatigue and a large proportion incorporated an endurance training program. To build on the current evidence and progress MS-fatigue related recommendations, further studies with larger sample sizes and a more inclusive range of MS types are required. Finally, with a gap of research investigating the role of diet and sleep on motor and physical fatigue in MS, research into this field is critically needed.

Different Treatment Outcomes of Multiple Sclerosis Patients Receiving Ocrelizumab or Ofatumumab

OBJECTIVE

B-cell-depletion via CD20 antibodies is a safe and effective treatment for active relapsing multiple sclerosis (RMS). Both ocrelizumab (OCR) and ofatumumab (OFA) have demonstrated efficacy in randomized controlled trials and are approved for treatment of RMS, yet nothing is known on their comparative effectiveness, especially in the real-world setting.

METHODS

This prospective cohort study includes patients that were started on either OCR or OFA between September 2021 and December 2023. Patients were followed until June 2024 and recruited at 3 large tertiary centers in Germany (Duesseldorf, Essen, and Giessen). Propensity-score-matching was used to address baseline imbalances among patients. Clinical relapses, presence of new or enlarging MRI lesions and 6-month confirmed disability worsening were evaluated. Non-inferiority of OFA compared to OCR was evaluated through comparison of Kaplan-Meier-estimates.

RESULTS

A total of 1,138 patients were initially enrolled in the cohort. Following patient selection and propensity-score-matching, 544 OCR and 417 OFA patients were included in the final analysis. In our primary analysis, OFA was non-inferior to OCR in terms of relapses, disability progression, and accrual of MRI lesions. Subgroup analyses confirmed findings in previously naïve and platform-treated patients. Potential differences between OFA and OCR were seen in patients switching from S1P receptor modulators or natalizumab.

CONCLUSION

We here provide comparative data on the effectiveness of OCR and OFA in patients with active RMS. OFA was non-inferior to OCR in the overall cohort. Potential differences observed in patients switching from S1P receptor modulators or natalizumab require further validation. ANN NEUROL 2025;97:583-595.

Conventional and Advanced Magnetic Resonance Imaging Biomarkers of Multiple Sclerosis in the Brain

Multiple sclerosis (MS) is a heterogeneous disease, and each MS patient exhibits different clinical symptoms that are reflected in their magnetic resonance imaging (MRI) results. Each MS lesion should be interpreted carefully and evaluated in conjunction with a clinical examination. MRI plays a major role in evaluating how MS lesions are aggregated in the central nervous system and how they change over time. There are several conventional MRI biomarkers of MS that could be utilized to evaluate each MS phenotype. MRI is useful for clinical decisions, aiding in the determination of disease-modifying treatment or disease prognosis. Despite its higher sensitivity, MRI provides low specificity due to the heterogeneity of MS lesions. However, advanced MRI biomarkers show promise in terms of defining MS lesions, as each imaging biomarker correlates differently with the clinical scenario of each MS phenotype. The aim of this review is to summarise the current state of MRI biomarkers for MS in the brain and how they relate to neurological disabilities.

Central American and Caribbean consensus for the treatment of MS, NMOSD, and MOGAD

BACKGROUND

In recent years, significant progress has been made in immune demyelinating disorders, particularly regarding early diagnosis and disease-modifying drugs (DMDs). Despite advancements, socioeconomic factors in many Latin American countries present unique challenges that impede the proper identification and management of these disorders.

OBJECTIVES

The updated consensus from the Central American and Caribbean working group strives to enhance the management of Multiple Sclerosis (MS), Neuromyelitis Optica Spectrum Disorder (NMOSD), and Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD) by offering a framework for incorporating available treatment into clinical practice.

METHODS

The authors conducted an extensive bibliographic search and followed a consensus process that included input from forum members to present a new, revised, and finalized report.

RESULTS

The consensus, endorsed by over 70% of members, covers the application of DMDs, biologic agents, glucocorticoids, definitions of therapeutic failure, patient monitoring, cessation of treatment, prognosis, therapy use during pregnancy and lactation, and vaccination in patients initiating or on DMDs or biologic treatments.

CONCLUSION

The revised consensus and guidelines aim to enhance long-term outcomes in these regions by assisting patients, regulatory bodies, healthcare providers, and policymakers.

Autologous haematopoietic stem cell transplantation for treatment of multiple sclerosis and neuromyelitis optica spectrum disorder - recommendations from ECTRIMS and the EBMT

Autologous haematopoietic stem cell transplantation (AHSCT) is a treatment option for relapsing forms of multiple sclerosis (MS) that are refractory to disease-modifying therapy (DMT). AHSCT after failure of high-efficacy DMT in aggressive forms of relapsing-remitting MS is a generally accepted indication, yet the optimal placement of this approach in the treatment sequence is not universally agreed upon. Uncertainties also remain with respect to other indications, such as in rapidly evolving, severe, treatment-naive MS, progressive MS, and neuromyelitis optica spectrum disorder (NMOSD). Furthermore, treatment and monitoring protocols, rehabilitation and other supportive care before and after AHSCT need to be optimized. To address these issues, we convened a European Committee for Treatment and Research in Multiple Sclerosis Focused Workshop in partnership with the European Society for Blood and Marrow Transplantation Autoimmune Diseases Working Party, in which evidence and key questions were presented and discussed by experts in these diseases and in AHSCT. Based on the workshop output and subsequent written interactions, this Consensus Statement provides practical guidance and recommendations on the use of AHSCT in MS and NMOSD. Recommendations are based on the available evidence, or on consensus when evidence was insufficient. We summarize the key evidence, report the final recommendations, and identify areas for further research.

Neuroinmunological diseases in paediatric patients: New entities and update

Neuroinmunological diseases are a broad heterogeneous group of inflammatory disorders in which damage to the central nervous system occurs as a result of immune system abnormalities that can be caused by various pathogenic mechanisms. This may be produced by the presence of autoantibodies, mediated by cells, triggered by infections and paraneoplastic processes, or have a genetic cause. Radiologists should be familiar with these diseases and be able to perform a differential diagnosis, as early diagnosis and appropriate treatment with immunotherapy can modify the course of the disease in some cases. This update has two objectives: Review the most common entities within each group, including demyelinating diseases, autoimmune encephalitis, lupus erythematosus, Rasmussen's encephalitis, and haemophagocytic lymphohistiocytosis. Describe key imaging features that aid in the differential diagnosis between different entities.

Long-Term Treatment With Ocrelizumab in Patients With Early-Stage Relapsing MS: Nine-Year Data From the OPERA Studies Open-Label Extension

BACKGROUND AND OBJECTIVES

Patients with multiple sclerosis (MS) may demonstrate better disease control when treatment is initiated on high-efficacy disease-modifying therapies (DMTs) from onset. This subgroup analysis assessed the long-term efficacy and safety profile of the high-efficacy DMT ocrelizumab (OCR) as first-line therapy for early-stage relapsing MS (RMS).

METHODS

Post hoc exploratory analyses of efficacy and safety were performed in a subgroup of treatment-naive patients with RMS who received ≥1 dose of OCR in the multicenter OPERA I/II (NCT01247324/NCT01412333) studies. Patients were randomized to OCR or interferon β-1a for 96 weeks (double-blind controlled treatment period [DBP]), before switching to OCR in the open-label extension (OLE). Efficacy assessments included no evidence of disease activity (NEDA-3), 24-week confirmed disability progression (CDP), MRI lesion activity, change in whole-brain volume; with safety outcomes assessed over a 9-year treatment period.

RESULTS

Overall, 757 patients were included (interferon-treated n = 382, mean age 36.3 years, 65.7% female; OCR-treated n = 375, mean age 35.5 years, 64.0% female); 505 of 757 (66.7%) completed 9 years of follow-up. The difference in NEDA status between OCR-treated and interferon-treated patients achieved during the DBP (72.5% and 43.8%, respectively, odds ratio 3.48, 95% CI 2.52-4.81) was maintained throughout the 7-year OLE (48.2% vs 25.7%; odds ratio 2.72, 95% CI 1.94-3.82). No 24-week CDP was observed in 78.7% of OCR-treated patients over 9 years. Brain volume loss over the entire study period remained numerically higher among patients starting OCR later (p = 0.09 at OLE at week 336). During the DBP, safety profiles in both groups were similar; no new safety signals were observed during the OLE. Over >9 years of continuous OCR treatment, the rate of infections remained low and stable over time.

DISCUSSION

A higher proportion of OCR-treated patients achieved NEDA status compared with interferon-treated patients during the DBP, which was maintained throughout the OLE. After switching to OCR, disability accrual and brain volume loss among interferon-treated patients became similar to the OCR-OCR group, but disability and brain volume loss accrued during interferon treatment were not recovered. Possible study limitations include assessment bias due to unmaintained blinding during the OLE. These data support OCR as first-line therapy for these patients.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that OCR delays disease progression in treatment-naïve patients with early-stage RMS.

Age-Related Disability Outcomes After a First Demyelinating Event

BACKGROUND AND OBJECTIVES

Emerging concepts in the early detection of multiple sclerosis (MS) progression reveal that disability accumulation can start early in the disease course. Aging in MS is increasingly recognized as a key factor for disease progression and disability accrual. We evaluate the prognostic impact of age in a cohort of patients experiencing a first demyelinating event (FDE), using a variety of disability outcomes, including some not previously assessed in age-specific studies.

METHODS

Patients aged 18-50 years, assessed within 3 months from the FDE, were prospectively included since 1994 and categorized into 3 age groups: 18-29, 30-39, and 40-50 years. Relapse-associated worsening (RAW) at FDE, annualized relapse rate, and EDSS trajectories during follow-up were compared across age groups. Cox regression analyses adjusted for sex, comorbidities, and time exposed to very high-efficacy drugs were performed to assess the risk of achieving the following outcomes: time to reach McDonald 2017 criteria, first relapse, recurrent RAW, >2 new T2 brain lesions/year, first progression independent of relapse activity (PIRA), confirmed disability accumulation (CDA), and confirmed EDSS score 3.0. Patient-reported outcome measures were also analyzed.

RESULTS

A total of 1,170 patients were included (median age 32 years; 69% female). The 40-50 group had a higher proportion of RAW at FDE (34% vs 25% and 29%; p = 0.031) and less time exposed to very high-efficacy treatments (p < 0.001) than the 30-39 and 18-29 groups, respectively. EDSS trajectories in the 40-50 group displayed a greater annual increase in the EDSS score compared with the 18-29 group (β 0.019 [95% CI 0.0001; 0.0387]). Cox analyses (HR; 95% CI) showed that the 40-50 group was at lower risk to reach McDonald 2017 criteria (0.80; 0.67-0.96), first relapse (0.59; 0.47-0.74), recurrent RAW (0.51; 0.31-0.86), or >2 new T2 brain lesions/year (0.39; 0.30-0.52), but at a higher risk of CDA (1.49; 1.16-1.97), PIRA (2.48; 1.88-3.27), and EDSS score 3.0 (1.50; 1.05-2.12), than the 18-29 group. Different functional and well-being variables were more affected in the 40-50 group, compared with 30-39 and 18-29 groups (p values< 0.05).

DISCUSSION

Patients with a FDE at 40-50 years exhibit less inflammatory outcomes compared with younger patients and reach outcomes more closely related to neurodegeneration despite the lower disease activity.

MRI management of NMOSD and MOGAD: Proposals from the French Expert Group NOMADMUS

BACKGROUND

Currently, there are no available recommendations or guidelines on how to perform MRI monitoring in the management of neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). The issue is to determine a valuable MRI monitoring protocol to be applied in the management of NMOSD and MOGAD, as previously proposed for the monitoring of multiple sclerosis.

OBJECTIVES

The objectives of this work are to establish proposals for a standardized and feasible MRI acquisition protocol, and to propose control time points for systematic MRI monitoring in the management of NMOSD and MOGAD.

METHODS

A steering committee composed of 7 neurologists and 5 neuroradiologists, experts in NMOSD and MOGAD from the French group NOMADMUS, defined 8 proposals based on their expertise and a review from the literature. These proposals were then submitted to a Rating Group composed of French NMOSD / MOGAD experts.

RESULTS

In the management of NMOSD and MOGAD, a consensus has been reached to perform systematic MRI of the brain, optic nerve and spinal cord, including cauda equina nerve roots, at the time of diagnosis, both without and after gadolinium administration. Moreover, it has been agreed to perform a systematic MRI scan 6 months after diagnosis, focusing on the area of interest, both without and after gadolinium administration. For long-term follow-up of NMOSD and MOGAD, and in the absence of clinical activity, it has been agreed to perform gadolinium-free MRI of the brain (+/- optic nerves) and spinal cord, every 36 months. Ideally, these MRI scans should be performed on the same MRI system, preferably a 3T MRI system for brain and optic nerve MRI, and at least a 1.5T MRI system for spinal cord MRI.

CONCLUSIONS

This expert consensus approach provides physicians with proposals for the MRI management of NMOSD and MOGAD.

Approach to Managing the Initial Presentation of Multiple Sclerosis: A Worldwide Practice Survey

Background and Objectives

Available disease-modifying therapies (DMTs) for multiple sclerosis (MS) are rapidly expanding; although escalation approaches aim to balance safety and efficacy, emerging evidence suggests superior outcomes for people with MS who are exposed to early high-efficacy therapies. We aimed to explore practice differences in prevailing management strategies for relapsing-remitting MS.

Methods

We used a worldwide electronic survey launched by the Practice Current section of Neurology® Clinical Practice. Questions pertained to a case of a 37-year-old woman presenting with optic neuritis. Respondents were asked to indicate their initial investigations, relapse management strategy, choice of disease-modifying therapy, and plan for follow-up imaging (contrast/noncontrast). Survey responses were stratified by key demographic variables along with 95% confidence intervals (95% CIs).

Results

We received 153 responses from 42 countries; 32.3% responders identified as MS specialists. There was a strong preference for intravenous delivery of high-dose corticosteroids (87.7%, 95% CI 80.7-92.5), and most of the responders (61.3%, 95% CI 52.6-69.4) indicated they would treat a nondisabling (mild sensory) MS relapse. When asked to select a single initial DMT, 56.6% (95% CI 47.6-65.1) selected a high-efficacy therapy (67.5% MS specialists vs 53.7% non-MS specialists). The most selected agents overall were fingolimod (14.7%), natalizumab (15.5%), and dimethyl fumarate (20.9%). Two-thirds of respondents indicated they would request contrast-enhanced surveillance MRI.

Discussion

Although there is a slight preference for initiating high-efficacy DMT at the time of initial MS diagnosis, opinions regarding the most appropriate treatment paradigm remain divided.

Retinal thinning differentiates treatment effects in relapsing multiple sclerosis below the clinical threshold

OBJECTIVE

To investigate retinal layer thinning as a biomarker of disease-modifying treatment (DMT) effects in relapsing multiple sclerosis (RMS).

METHODS

From an ongoing prospective observational study, we included patients with RMS, who (i) had an optical coherence tomography (OCT) scan within 6 to 12 months after DMT start (rebaseline) and ≥1 follow-up OCT ≥12 months after rebaseline and (ii) adhered to DMT during follow-up. Differences between DMT in thinning of peripapillary-retinal-nerve-fiber-layer (pRNFL) and macular ganglion cell-plus-inner plexiform-layer (GCIPL) were analyzed using mixed-effects linear regression. Eyes suffering optic neuritis during follow-up were excluded.

RESULTS

We included 291 RMS patients (mean age 30.8 years [SD 7.9], 72.9% female, median disease duration 9 months [range 6-94], median rebaseline-to-last-follow-up-interval 32 months [12-82]). Mean annualized rates of retinal layer thinning (%/year) in reference to DMF (n = 84, GCIPL 0.28, pRNFL 0.53) were similar under TERI (n = 18, GCIPL 0.34, pRNFL 0.59), GLAT (n = 24, GCIPL 0.32, pRNFL 0.56), and IFNb (n = 13, GCIPL 0.33, pRNFL 0.60) were slightly lower under S1PM (n = 27, GCIPL 0.19, pRNFL 0.42) and CLA (n = 23, GCIPL 0.20, pRNFL 0.42), and were significantly lower under NTZ (n = 47, GCIPL 0.09, pRNFL 0.24; both p < 0.001) and antiCD20 (n = 55, GCIPL 0.10, pRNFL 0.23; both p < 0.001). In patients achieving NEDA-2, observed thinning rates were lower overall, but still significantly lower under NTZ and antiCD20.

INTERPRETATION

Applying a rebaselining concept, retinal layer thinning differentiates DMT effects even in clinically stable patients and, thus, might be a useful biomarker to monitor DMT efficacy on subclinical neuroaxonal degeneration-at least on a group level.

Discontinuation of First-Line Disease-Modifying Therapy in Patients With Stable Multiple Sclerosis: The DOT-MS Randomized Clinical Trial

Importance

Increasing numbers of people with multiple sclerosis (MS) use disease-modifying therapy (DMT). Long-term stable disease while taking such medications provides a rationale for considering DMT discontinuation given patient burden, costs, and potential adverse effects of immunomodulating therapy.

Objective

To investigate whether first-line DMT can be safely discontinued in patients with long-term stable MS.

Design, Setting, and Participants

This multicenter, rater-blinded, noninferiority randomized clinical trial was conducted between July 1, 2020, and March 20, 2023, at 14 Dutch centers. Data analysis was performed between July 2023 and January 2024. Key inclusion criteria were relapse-onset MS, aged 18 years or older, without relapses, and without substantial magnetic resonance imaging (MRI) activity in the previous 5 years under first-line DMT. Participants were randomized 1:1 to discontinue or continue first-line DMT.

Intervention

Discontinuation of first-line DMT.

Main Outcome and Measure

The primary outcome was significant inflammatory disease activity, defined as relapse and/or 3 or more new T2 lesions or 2 or more contrast-enhancing lesions on brain MRI.

Results

Of 163 potentially eligible participants, 89 participants were included in the trial at the moment of early termination. Forty-four participants (49.4%) were assigned to the continue group and 45 participants (50.6%) were assigned to the discontinue group. Median (IQR) age was 54.0 (49.0-59.0) years, and 60 participants (67.4%) were female. Two participants in the continue group were lost to follow-up. After a median (IQR) follow-up time of 15.3 (11.4-23.9) months, the trial was prematurely terminated because of inflammatory disease activity recurrence above the predefined limit. In total, 8 of 45 participants in the discontinue group (17.8%) vs 0 of 44 participants in the continue group reached the primary end point and had recurrent, mostly radiological inflammation. Two of these 8 participants had a clinical relapse. Median (IQR) time to disease activity was 12.0 (6.0-12.0) months.

Conclusions and Relevance

In this randomized clinical trial, even in patients with long-term MS stable for over 5 years, first-line DMT discontinuation can lead to recurrence of inflammatory disease activity. Although this study cohort was relatively small, the recurrence of inflammation in the discontinue group was significantly higher than in the continue group and also higher than in the previously published DISCOMS trial, which only included individuals aged 55 years or older. This study provides additional data, especially in a younger population and including longitudinal biomarker measurements, for informed decision-making in cases when treatment discontinuation is considered.

Trial Registration

ClinicalTrials.gov Identifier: NCT04260711.

Typical and Emerging Diagnostic MRI Features in Multiple Sclerosis

Magnetic resonance imaging (MRI) stands as the most sensitive paraclinical technique for detecting the demyelinating lesions characteristic of multiple sclerosis (MS). Consequently, MRI plays a pivotal role in establishing an accurate and timely diagnosis of the disease, ultimately based on the application of the McDonald criteria. Early diagnosis is particularly important as it facilitates the prompt initiation of disease-modifying treatments, deemed most effective during the initial phases of MS. This review article examines the recommended standardized MRI protocol, as well as the classic imaging features of MS in the brain, optic nerve, and spinal cord, capable of discriminating, in most cases, MS from other disorders that can mimic this disease. Additionally, novel MR imaging findings, such as the central vein sign and paramagnetic rim lesion, which have been proposed as new imaging biomarkers to enhance diagnostic specificity for MS, are also discussed. These emerging features are likely to be incorporated in the future iterations of the McDonald criteria, and therefore, radiologists should be familiar with their appearance and with the optimal MRI protocols required for their detection.

AI-based assessment of longitudinal multiple sclerosis MRI: Strengths and weaknesses in clinical practice

OBJECTIVES

In Multiple Sclerosis (MS) cerebral MRI is essential for disease and treatment monitoring. For this purpose, software solutions are available to support the radiologist with image interpretation and reporting of follow up imaging. Aim of this study was to evaluate an AI based software for longitudinal lesion detection with clinical data and to determine the influence of different MRI machines in such setting.

METHODS

The database of a university hospital was screened for all follow up MRI of MS patients performed in 2023. The examinations were categorized in "initial and follow up imaging at the same MRI" or "initial and follow up imaging at different MRI". The examinations were analysed with the AI based software mdbrain. The results concerning new and enlarging lesions were compared with the clinical radiologic report and with a gold standard reading.

RESULTS

101 MRIs were performed at the same MRI machine and 130 at different scanners. The AI based software had a high sensitivity (1 and 0.786) and an acceptable specificity (0.74 and 0.549) concerning new or enlarging lesions in both settings. The negative predictive value was high (1 and 0.954), whereas the positive predictive value was low due to false positive new or enlarging lesions (0.444 and 0.177). The reasons for false positive lesions differed markedly in both groups.

CONCLUSION

For the evaluation of follow up MR images of MS patients, an AI-based imaging analysis can be beneficial in clinical routine, especially due to a very high negative predictive value.

Ultra-High Contrast (UHC) MRI of the Brain, Spinal Cord and Optic Nerves in Multiple Sclerosis Using Directly Acquired and Synthetic Bipolar Filter (BLAIR) Images

In this educational review, the basic physics underlying the use of ultra-high contrast (UHC) bipolar filter (BLAIR) sequences, including divided subtracted inversion recovery (dSIR), is explained. These sequences can increase the contrast produced by small changes in T1 by a factor of ten or more compared with conventional IR sequences. In illustrative cases, the sequences were used in multiple sclerosis (MS) patients during relapse and remission and were compared with positionally matched conventional (T2-weighted spin echo, T2-FLAIR) images. Well-defined focal lesions were seen with dSIR sequences in areas where little or no change was seen with conventional sequences. In addition, widespread abnormalities affecting almost all of the white matter of the brain were seen during relapses when there were no corresponding abnormalities seen on conventional sequences (the whiteout sign). Grayout signs, in which there is a loss of contrast in gray matter or between gray matter and CSF, were also seen, as well as high signal boundaries around lesions. Disruption of the usual high signal boundary between white and gray matter was seen in leucocortical lesions. Lesions in the spinal cord were better seen or only seen with dSIR sequences. Generalized change was observed in the optic nerve with the dSIR sequence in a case of optic neuritis. UHC BLAIR sequences may be of considerable value for recognition of abnormalities in clinical practice and in research studies on MS.

From diagnosis to treatment: exploring the mechanisms underlying optic neuritis in multiple sclerosis

Multiple sclerosis (MS) is a chronic autoimmune disease affecting the central nervous system, commonly causing sensory disturbances, motor weakness, impaired gait, incoordination and optic neuritis (ON). According to the statistics, up to 50% of MS patients experience vision problems during the disease course, suffering from blurred vision, pain, color vision deficits, and even blindness. Treatments have progressed from corticosteroids to therapies targeted against B/T cells. This review comprehensively and systematically reappraises the diagnostic methods for visual impairment in MS patients. It also summarizes the most recent treatment approaches and effective medications for ON in MS. Finally, we examine the immunoinflammatory mechanisms that underlie lesions in the central nervous system in multiple sclerosis, in order to direct future investigations to confirm these mechanisms in the visual pathway.

Exploring the Pathophysiology, Diagnosis, and Treatment Options of Multiple Sclerosis

The complicated neurological syndrome known as multiple sclerosis (MS) is typified by demyelination, inflammation, and neurodegeneration in the central nervous system (CNS). Managing this crippling illness requires an understanding of the complex interactions between neurophysiological systems, diagnostic techniques, and therapeutic methods. A complex series of processes, including immunological dysregulation, inflammation, and neurodegeneration, are involved in the pathogenesis of MS. Gene predisposition, autoreactive T cells, B cells, and cytokines are essential participants in the development of the disease. Demyelination interferes with the ability of the CNS to transmit signals, which can cause a variety of neurological symptoms, including impaired motor function, sensory deficiencies, and cognitive decline. Developing tailored therapeutics requires understanding the underlying processes guiding the course of the disease. Neuroimaging, laboratory testing, and clinical examination are all necessary for an accurate MS diagnosis. Evoked potentials and cerebrospinal fluid studies assist in verifying the diagnosis, but magnetic resonance imaging (MRI) is essential for identifying distinctive lesions in the CNS. Novel biomarkers have the potential to increase diagnostic precision and forecast prognosis. The goals of MS treatment options are to control symptoms, lower disease activity, and enhance quality of life. To stop relapses and reduce the course of the disease, disease-modifying treatments (DMTs) target several components of the immune response. DMTs that are now on the market include interferons, glatiramer acetate, monoclonal antibodies, and oral immunomodulators; each has a unique mode of action and safety profile. Symptomatic treatments improve patients' general well-being by addressing specific symptoms, including pain, sphincter disorders, fatigue, and spasticity. Novel treatment targets, neuroprotective tactics, and personalized medicine techniques will be the main focus of MS research in the future. Improving long-term outcomes for MS patients and optimizing disease treatment may be possible by utilizing immunology, genetics, and neuroimaging developments. This study concludes by highlighting the complexity of multiple MS, including its changing therapeutic landscape, diagnostic problems, and neurophysiological foundations. A thorough grasp of these elements is essential to improving our capacity to identify, manage, and eventually overcome this intricate neurological condition.

MRI versus relapse: optimal activity monitoring for management of progressive multiple sclerosis

Secondary progressive multiple sclerosis is often categorized as 'active'/'non-active' based on inflammatory activity on MRI, or relapse; however, the value of MRI/relapse as indicators of disease activity in real-world and clinical trial settings merits further investigation. We separately analysed retrospective data from patients with clinically diagnosed secondary progressive multiple sclerosis in the Adelphi Real-World Disease Specific Programme (a cross-sectional survey) in multiple sclerosis (Adelphi: n = 2554) and the placebo group of the Phase III EXploring the efficacy and safety of siponimod in PAtients with secoNDary progressive multiple sclerosis (EXPAND) trial, [EXPAND-PBO (placebo group of the EXPAND): n = 546] to assess: differences between active/non-active disease in the real-world (characteristics; monitoring); the value of MRI and relapse to indicate disease activity; and the number and characteristics of non-active patients with disease activity in the clinical study. In Adelphi, 1889 patients had 'active' disease (≥1 relapse in the year before index date and/or ≥1 new lesion on most recent MRI) versus 665 with 'non-active' disease (no relapses in the previous year and no new lesions on MRI); median age was 48 versus 53 years; 73.5 versus 87.8% had moderate-to-severe disease; 75.7 versus 54.3% were taking disease-modifying treatment; 87.7 versus 58.7% had received an MRI in the past year. Most active cases (n = 1116; 59.1%) were identified by MRI versus 239 (12.7%) by relapse and 534 (28.3%) by MRI plus relapse. In EXPAND-PBO, 263 patients were classified 'active' (≥1 relapse in 2 years before screening and/or ≥1 gadolinium-enhancing lesion) and 270 'non-active' (no relapse in the 2 years before screening and no gadolinium-enhancing lesion[s]) at baseline; similar proportions of these groups had received disease-modifying treatment prior to placebo: 77.2 and 80.7%. Of non-active patients, 53.0% had disease activity on study; in these patients, 74.1% had disease activity identified by MRI, 8.4% by relapse, and 17.5% by MRI plus relapse. In patients classified non-active at baseline: age and percentage with Expanded Disability Status Scale score 6.0-6.5 were similar between patients with disease activity on study versus patients who remained non-active: 48 versus 52 years; 49.7 versus 56.7%, respectively. In real-world and clinical trial settings, MRI could be a better option than relapse for the identification of disease activity. However, in the real-world, fewer non-active patients had received an MRI in the last year than active patients, which is concerning given that most disease activity in EXPAND-PBO was identified via MRI. We highlight difficulties in consistently identifying disease activity and the negative implications of infrequent monitoring of non-active disease.

Using disease-modifying treatments in multiple sclerosis: Association of British Neurologists (ABN) 2024 guidance

The Association of British Neurologists last published guidelines on disease-modifying treatment (DMT) in multiple sclerosis (MS) in 2015. Since then, additional DMTs have been licensed and approved for prescribing within the National Health Service for relapsing-remitting MS, early primary progressive MS and active secondary progressive MS. This updated guidance provides a consensus-based approach to using DMTs. We provide recommendations for eligibility, starting, monitoring, switching and stopping of DMTs; pregnancy; equitable access to DMT; autologous haemopoietic stem-cell transplantation; and use of generics. We highlight best practice where it exists and discuss future priorities.

MRI-based morphometric structural changes correlate with histopathology in experimental autoimmune encephalomyelitis

BACKGROUND AND OBJECTIVES

Magnetic resonance imaging (MRI) and neurohistopathology are important correlates for evaluation of disease progression in multiple sclerosis (MS). Here we used experimental autoimmune encephalomyelitis (EAE) as an animal model of MS to determine the correlation between clinical EAE severity, MRI and histopathological parameters.

METHODS

N = 11 female C57BL/6J mice were immunized with human myelin oligodendrocyte glycoprotein 1-125, while N = 9 remained non-immunized. Mice were scanned longitudinally over a period of 13 weeks using a 11.7 Tesla (T) Bruker BioSpec® preclinical MRI instrument, and regional volume changes of the lumbar spinal cord were analyzed using Voxel-Guided Morphometry (VGM). Following the final in vivo T1-weighted MRI scan, the lumbar spinal cord of each mouse was subjected to an ex vivo MRI scan using T1-, T2*- and diffusion tensor imaging (DTI)-weighted sequences. Tissue sections were then stained for immune cell infiltration, demyelination, astrogliosis, and axonal damage using hematoxylin-eosin staining and immunohistochemistry.

RESULTS

While in vivo MRI VGM detected an overall increase in volume over time, no differences were observed between EAE animals and controls. Ex vivo MRI showed a generalized atrophy of the spinal cord, which was pronounced in the anterolateral tract. The most striking correlation was observed between EAE score, white matter atrophy in ex vivo T1-weighted scans and histological parameters.

DISCUSSION

The data demonstrate that ex vivo MRI is a valuable tool to assess white matter atrophy in EAE, which was shown to be directly linked to the severity of EAE and spinal cord histopathology.

Pure spinal multiple sclerosis: A case series of a possible new entity

BACKGROUND

Recent literature describes a condition similar to multiple sclerosis (MS) but with demyelinating lesions limited to the spinal cord. This condition, referred to as "pure spinal" MS, might benefit from disease-modifying treatment (DMT).

METHODS

We screened the medical records of approximately 8000 patients with demyelinating diseases at the Isfahan MS clinic in Iran. Criteria for inclusion in the case series were adults with a demyelinating disease limited to the spinal cord, positive oligoclonal IgG bands in cerebrospinal fluid (CSF), and negative results for other potential diagnoses.

RESULTS

Seven people with pure spinal MS were identified (all women, mean age [SD]: 40.14 [6.17] years at the first visit, mean follow-up duration [SD]: 98 [39.41] months). Two had a family history of conventional MS in their siblings. All patients exhibited lower limb weakness and tested negative for anti-MOG and anti-AQP4 antibodies. They experienced relapsing-remitting partial myelitis, with new spinal cord lesions on MRI but no extraspinal CNS lesions. DMT significantly reduced relapse rates in all patients, and two showed no increase in EDSS scores.

CONCLUSION

Pure spinal MS might be an atypical form of MS. Those affected may benefit from DMT; therefore, further investigation and consideration in the upcoming revisions of the McDonald criteria are recommended.

Unmasking the Area Postrema on MRI: Utility of 3D FLAIR, 3D-T2, and 3D-DIR Sequences in a Case-Control Study

The area postrema (AP) is a key circumventricular organ involved in the regulation of autonomic functions. Accurate identification of the AP via MRI is essential in neuroimaging but it is challenging. This study evaluated 3D FSE Cube T2WI, 3D FSE Cube FLAIR, and 3D DIR sequences to improve AP detection in patients with and without multiple sclerosis (MS). A case-control study included 35 patients with MS and 35 with other non-demyelinating central nervous system diseases (ND-CNSD). MRI images were acquired employing 3D DIR, 3D FSE Cube FLAIR, and 3D FSE Cube T2WI sequences. The evaluation of AP was conducted using a 3-point scale. Statistical analysis was performed with the chi-square test used to assess group homogeneity and differences between sequences. No significant differences were found in the visualization of the AP between the MS and ND-CNSD groups across the sequences or planes. The AP was not visible in 27.6% of the 3D FSE Cube T2WI sequences, while it was visualized in 99% of the 3D FSE Cube FLAIR sequences and 100% of the 3D DIR sequences. The 3D DIR sequence showed superior performance in identifying the AP.

High-Field-Blinded Assessment of Portable Ultra-Low-Field Brain MRI for Multiple Sclerosis

BACKGROUND AND PURPOSE

MRI is crucial for multiple sclerosis (MS), but the relative value of portable ultra-low field MRI (pULF-MRI), a technology that holds promise for extending access to MRI, is unknown. We assessed white matter lesion (WML) detection on pULF-MRI compared to high-field MRI (HF-MRI), focusing on blinded assessments, assessor self-training, and multiplanar acquisitions.

METHODS

Fifty-five adults with MS underwent pULF-MRI following their HF-MRI. Two neuroradiologists independently assessed pULF-MRI images in an evaluation process, including initial assessment blinded to HF-MRI, self-training with reference to HF-MRI and evaluation of 20 cases with additional T2-fluid-attenuated inversion recovery in an additional plane. A third rater conducted cross-referenced analysis with HF-MRI data to determine true-positive lesions, false-positive areas, and case-level sensitivity and positive predictive value.

RESULTS

The mean age of participants was 50 years (standard deviation: 11; 74% women). Initially, Rater 2 marked more false-positive areas than Rater 1 (p = 0.003). After self-training, both raters embraced a conservative approach, with Rater 2 marking fewer false-positive areas (p = 0.01). Both raters maintained 100% case-level sensitivity and positive predictive value for detecting at least one WML, particularly in periventricular areas. Multiplanar acquisitions reduced both false-positive areas and true-positive lesions. True-positive lesions and false-positive areas had similar contrast-to-noise ratios in the juxtacortical region (p = 0.73) but not in periventricular, deep parenchymal regions (p = 0.004, p = 0.01).

CONCLUSION

With adequate training, radiological interpretation of pULF-MRI has high sensitivity and positive predictive value for MS lesions but should be approached conservatively. These results suggest utility for patient triage, potentially reducing diagnostic delay, and screening high-risk individuals.

Structural-based uncertainty in deep learning across anatomical scales: Analysis in white matter lesion segmentation

This paper explores uncertainty quantification (UQ) as an indicator of the trustworthiness of automated deep-learning (DL) tools in the context of white matter lesion (WML) segmentation from magnetic resonance imaging (MRI) scans of multiple sclerosis (MS) patients. Our study focuses on two principal aspects of uncertainty in structured output segmentation tasks. First, we postulate that a reliable uncertainty measure should indicate predictions likely to be incorrect with high uncertainty values. Second, we investigate the merit of quantifying uncertainty at different anatomical scales (voxel, lesion, or patient). We hypothesize that uncertainty at each scale is related to specific types of errors. Our study aims to confirm this relationship by conducting separate analyses for in-domain and out-of-domain settings. Our primary methodological contributions are (i) the development of novel measures for quantifying uncertainty at lesion and patient scales, derived from structural prediction discrepancies, and (ii) the extension of an error retention curve analysis framework to facilitate the evaluation of UQ performance at both lesion and patient scales. The results from a multi-centric MRI dataset of 444 patients demonstrate that our proposed measures more effectively capture model errors at the lesion and patient scales compared to measures that average voxel-scale uncertainty values. We provide the UQ protocols code at https://github.com/Medical-Image-Analysis-Laboratory/MS_WML_uncs.

Enhancing classification of active and non-active lesions in multiple sclerosis: machine learning models and feature selection techniques

INTRODUCTION

Gadolinium-based T1-weighted MRI sequence is the gold standard for the detection of active multiple sclerosis (MS) lesions. The performance of machine learning (ML) and deep learning (DL) models in the classification of active and non-active MS lesions from the T2-weighted MRI images has been investigated in this study.

METHODS

107 Features of 75 active and 100 non-active MS lesions were extracted by using SegmentEditor and Radiomics modules of 3D slicer software. Sixteen ML and one sequential DL models were created using the 5-fold cross-validation method and each model with its special optimized parameters trained using the training-validation datasets. Models' performances in test data set were evaluated by metric parameters of accuracy, precision, sensitivity, specificity, AUC, and F1 score.

RESULTS

The sequential DL model achieved the highest AUC of 95.60% on the test dataset, demonstrating its superior ability to distinguish between active and non-active plaques. Among traditional ML models, the Hybrid Gradient Boosting Classifier (HGBC) demonstrated a commendable test AUC of 86.75%, while the Gradient Boosting Classifier (GBC) excelled in cross-validation with an AUC of 87.92%.

CONCLUSION

The performance of sixteen ML and one sequential DL models in the classification of active and non-active MS lesions was evaluated. The results of the study highlight the effectiveness of sequential DL approach and ensemble methods in achieving robust predictive performance, underscoring their potential applications in classifying MS plaques.

Chronic active lesions in multiple sclerosis: classification, terminology, and clinical significance

In multiple sclerosis (MS), increasing disability is considered to occur due to persistent, chronic inflammation trapped within the central nervous system (CNS). This condition, known as smoldering neuroinflammation, is present across the clinical spectrum of MS and is currently understood to be relatively resistant to treatment with existing disease-modifying therapies. Chronic active white matter lesions represent a key component of smoldering neuroinflammation. Initially characterized in autopsy specimens, multiple approaches to visualize chronic active lesions (CALs) in vivo using advanced neuroimaging techniques and postprocessing methods are rapidly emerging. Among these in vivo imaging correlates of CALs, paramagnetic rim lesions (PRLs) are defined by the presence of a perilesional rim formed by iron-laden microglia and macrophages, whereas slowly expanding lesions are identified based on linear, concentric lesion expansion over time. In recent years, several longitudinal studies have linked the occurrence of in vivo detected CALs to a more aggressive disease course. PRLs are highly specific to MS and therefore have recently been incorporated into the MS diagnostic criteria. They also have prognostic potential as biomarkers to identify patients at risk of early and severe disease progression. These developments could significantly affect MS care and the evaluation of new treatments. This review describes the latest knowledge on CAL biology and imaging and the relevance of CALs to the natural history of MS. In addition, we outline considerations for current and future in vivo biomarkers of CALs, emphasizing the need for validation, standardization, and automation in their assessment.

Multiple Sclerosis-like Lesions Induced by Radiation: A Case Report and Systematic Review of the Literature

Background/Objectives: Radiotherapy (RT) remains crucial in treating both primary and metastatic central nervous system cancer. Despite advancements in modern techniques that mitigate some toxic adverse effects, magnetic resonance imaging (MRI) scans still reveal a wide range of radiation-induced changes. Radiation can adversely affect neuroglial cells and their precursors, potentially triggering a demyelinating pattern similar to multiple sclerosis (MS). The aim of the current review is to investigate the occurrence and characteristics of such cases presented in the literature. Methods: We present the case of a 37-year-old female patient with multiple white matter lesions on a brain MRI, mimicking MS, after the completion of RT sessions. Additionally, a systematic review of the literature (PROSPERO id: CRD42024624053) was performed on 4 January 2024. The databases of MEDLINE and SCOPUS were searched. Case reports or case series of adult patients with white matter lesions in a brain MRI, consistent with the MAGNIMS criteria for MS plaques, after RT, were included in our final synthesis. The PRISMA guidelines were applied. Results: The systematic search of the literature revealed 1723 studies, 7 of which conformed to our inclusion criteria, including seven patients in our final analysis. Four of them were female and the mean age was 39 ± 11 years. Several intracranial and extracranial RT types were performed. The symptoms occurred 3 ± 0.8 months after the completion of RT. Lesions were revealed in infratentorial, periventricular and subcortical white matter regions, but not in the spinal cord. All patients who received corticosteroids (83%) showed clinical improvement. Clinical and radiological recurrence occurred in two of the patients during the follow-up period. Fingolimod and Interferon beta-1a were administered to these two patients. Conclusions: Radiation-induced demyelination is a critical clinical and radiological entity that requires attention from both oncologists and neurologists. Comprehensive follow-up is essential to identify patients who may benefit from disease-modifying therapies and to distinguish them from those with pre-existing demyelinating conditions.

Comparison between contrast-enhanced fat-suppressed 3D FLAIR brain MR images and T2-weighted orbital MR images at 3 Tesla for the diagnosis of acute optic neuritis

PURPOSE

The purpose of this study was to compare the capabilities of contrast-enhanced fat-suppressed (CE FS) three-dimensional fluid-attenuated inversion recovery (3D FLAIR) brain magnetic resonance imaging (MRI) with those of coronal T2-weighted orbital MRI obtained at 3 Tesla for the diagnosis of optic neuritis (ON).

MATERIALS AND METHODS

Patients who presented to our center with acute visual loss and underwent MRI examination of the orbits and the brain between November 2014 and February 2020 were retrospectively included. Three radiologists independently and blindly analyzed CE FS 3D FLAIR and coronal T2-weighted images. Disagreements in image interpretation were resolved by consensus with an independent neuroradiologist who was not involved in the initial reading sessions. The primary adjudication criterion for the diagnosis of ON was the presence of an optic nerve hypersignal. Sensitivity, specificity, and accuracy of CE 3D FLAIR brain images were compared with those of coronal T2-weighted orbital images using McNemar test. Artifacts were classified into three categories and compared between the two image sets.

RESULTS

A total of 1023 patients were included. There were 638 women and 385 men with a mean age of 42 ± 18.3 (standard deviation) years (age range: 6-92 years). Optic nerve hyperintensities were identified in 375/400 (94%) patients with ON using both 3D FLAIR and coronal T2-weighted images. Sensitivity, specificity, and accuracy of both sequences were 94% (95% CI: 91.3-96.1), 79% (95% CI: 75.5-82.2), and 89% (95% CI: 86.8-90.7), respectively. Optic disc hypersignal was detected in 120/400 patients (30%) using 3D FLAIR compared to 3/400 (0.75%) using coronal T2-weighted images (P < 0.001). Optic radiation hypersignal was observed in 2/400 (0.5%) patients using 3D FLAIR images. Significantly more artifacts (moderate or severe) were observed on coronal T2-weighted images (801/1023; 78%) by comparison with 3D FLAIR images (448/1023; 44%) (P < 0.001).

CONCLUSION

The performance of 3D FLAIR brain MRI for the diagnosis of ON is not different from that of coronal T2-weighted orbital MRI and its use for optic nerve analysis may be beneficial.