Atrophy In Multiple Sclerosis Research Articles

Senescence marker p16INK4a expression in patients with multiple sclerosis

ObjectivesTelomere attrition is associated with disability accumulation and brain atrophy in multiple sclerosis (MS). Downstream of telomere attrition is cellular senescence. We sought to determine differences in the cellular senescence marker p16INK4a expression between MS and healthy control participants and the association of p16INK4a expression with MS disability and treatment exposure. MethodsPatients meeting diagnostic criteria for MS and healthy controls were recruited for a cross-sectional pilot study. RNA was extracted from peripheral blood mononuclear cells (PBMCs) and p16INK4a expression levels were measured using qRT PCR. Spearman correlation coefficients and regression models were applied to compare expression levels to chronological age, assess case control differences, and determine associations with clinical outcome measures. ResultsFifty-two participants with MS (67 % female, ages 25–70) and 38 healthy controls (66 % female, ages 23–65) were included. p16INK4a levels were not linearly correlated with chronological age in MS (rhos = −0.01, p = 0.94) or control participants (rhos = 0.02, p = 0.92). Higher median p16INK4a levels were observed in the >50-year age group for MS (0.25, IQR 0.14–0.35) vs. controls (0.12, IQR 0.05–0.15) and in this age group B cell depletion therapy was associated with lower expression levels. p16INK4a expression was not associated with any of the measured MS disability outcomes. DiscussionCaution is needed with using p16INK4a expression level from PBMCs as an aging biomarker in MS participants, given lack of correlation with chronological age or large associations with clinical outcomes.

Exploring the effects of extended interval dosing of natalizumab and drug concentrations on brain atrophy in multiple sclerosis.

Extended interval dosing (EID) of natalizumab treatment is increasingly used in multiple sclerosis. Besides the clear anti-inflammatory effect, natalizumab is considered to have neuroprotective properties as well. This study aimed to study the longitudinal effects of EID compared to standard interval dosing (SID) and natalizumab drug concentrations on brain atrophy. Patients receiving EID or SID of natalizumab with a minimum radiological follow-up of 2 years were included. Changes in brain atrophy measures over time were derived from clinical routine 3D-Fluid Attenuated Inversion Recovery (FLAIR)-weighted magnetic resonance imaging (MRI) scans using SynthSeg. We found no differences between EID (n = 32) and SID (n = 50) for whole brain (-0.21% vs -0.16%, p = 0.42), ventricular (1.84% vs 1.13%, p = 0.24), and thalamic (-0.32% vs -0.32%, p = 0.97) annualized volume change over a median follow-up of 3.2 years. No associations between natalizumab drug concentration and brain atrophy rate were found. We found no clear evidence that EID compared to SID or lower natalizumab drug concentrations have a negative impact on the development of brain atrophy over time.

Systemic inflammation associates with and precedes cord atrophy in progressive multiple sclerosis.

In preclinical models of multiple sclerosis, systemic inflammation has an impact on the compartmentalized inflammatory process within the central nervous system and results in axonal loss. It remains to be shown whether this is the case in humans, specifically whether systemic inflammation contributes to spinal cord or brain atrophy in multiple sclerosis. Hence, an observational longitudinal study was conducted to delineate the relationship between systemic inflammation and atrophy using magnetic resonance imaging: the SIMS (Systemic Inflammation in Multiple Sclerosis) study. Systemic inflammation and progression were assessed in people with progressive multiple sclerosis (n = 50) over two and a half years. Eligibility criteria included: (i) primary or secondary progressive multiple sclerosis; (ii) age ≤ 70; and (iii) Expanded Disability Status Scale ≤ 6.5. First morning urine was collected weekly to quantify systemic inflammation by measuring the urinary neopterin-to-creatinine ratio using a validated ultra-performance liquid chromatography mass spectrometry technique. The urinary neopterin-to-creatinine ratio temporal profile was characterized by short-term responses overlaid on a background level of inflammation, so these two distinct processes were considered as separate variables: background inflammation and inflammatory response. Participants underwent MRI at the start and end of the study, to measure cervical spinal cord and brain atrophy. Brain and cervical cord atrophy occurred on the study, but the most striking change was seen in the cervical spinal cord, in keeping with the corticospinal tract involvement that is typical of progressive disease. Systemic inflammation predicted cervical cord atrophy. An association with brain atrophy was not observed in this cohort. A time lag between systemic inflammation and cord atrophy was evident, suggesting but not proving causation. The association of the inflammatory response with cord atrophy depended on the level of background inflammation, in keeping with experimental data in preclinical models where the effects of a systemic inflammatory challenge on tissue injury depended on prior exposure to inflammation. A higher inflammatory response was associated with accelerated cord atrophy in the presence of background systemic inflammation below the median for the study population. Higher background inflammation, while associated with cervical cord atrophy itself, subdued the association of the inflammatory response with cord atrophy. Findings were robust to sensitivity analyses adjusting for potential confounders and excluding cases with new lesion formation. In conclusion, systemic inflammation associates with, and precedes, multiple sclerosis progression. Further work is needed to prove causation since targeting systemic inflammation may offer novel treatment strategies for slowing neurodegeneration in multiple sclerosis.

30 Hippocampal Internal Architecture Subfield Volumes Associated with Systematic Inflammatory Biomarkers in Multiple Sclerosis

Objective:Multiple Sclerosis (MS) affects up to 500,000 adults in the United States, with cognitive impairment present in 45%-65% of people. Studies showed hippocampal atrophy in MS, but the underlying mechanisms remain unknown. Inflammation has been proposed to play a significant role, and associations between systemic inflammatory biomarkers and hippocampal atrophy have been shown in other neurological conditions. However, research exploring serum biomarker and volumetric associations in MS are lacking. Given that conventional imaging methods lack resolution for hippocampal internal architecture (HIA), new protocols were developed. We used the High-Resolution Multiple Image Co-Registration and Averaging (HR-MICRA) method to visualize the HIA subfields. We investigated the relationship between subfield volumes generated from HR-MICRA scans and systemic serum biomarkers in MS.Participants and Methods:Patients with MS were recruited (N= 34, mean age= 54.6, 35.3% Black) underwent Magnetic Resonance Imaging (MRI), and serum biomarkers were obtained, specifically chosen for their potential role in MS. Inflammatory biomarkers included; granulocyte colony stimulating factor (G-CSF), interleukin-10 (IL-10), matrix metalloproteinase-9 (MMP-9), tumor necrosis factor- a (TNF- a), and growth factors; vascular endothelial growth factor (VEGF); insulin-like growth factor-1 (IGF-1), and brain derived growth factor (BDNF). Imaging was performed in a Siemens Prisma 3T scanner with a 64-channel head coil using the HR-MICRA method. Hippocampal subfields were calculated using the Automated Segmentation of Hippocampal Subfields (ASHS) package. We used the Magdeburg Young Adult 7T Atlas for sub-hippocampal structures and Penn Temporal Lobe Epilepsy T1-MRI Whole Hippocampus ASHS Atlas for general hippocampal structure and segmentation. Pearson's product-moment analyses provided correlations between biomarkers and hippocampal subfield volumes for each cerebral hemisphere. A statistical significance level of p < 0.05 was used for all analyses.Results:Correlations emerged between left hemisphere Cornu Ammonis (CA) 2 and G-CSF (r = -.384; p = .025); IL-10 (r = -.342; p = .048); VEGF (r = -.371; p= .031); and CA3 with IL-10 (r = -.488, p = .003); G-CSF (r = -.386; p= .024); VEGF (r = -.352; p= .041). Dentate gyrus correlated with MMP-9 (r =.416; p=.014); IL-10 (r = -.365; p =.034). BDNF was correlated with right hemisphere CA1 (r = -.417, p = .014), CA2 (r = -.497; p= .003) and CA3 (r = -.451; p=.007).Conclusions:In our sample of persons with MS, left hemisphere hippocampal subfield volumes were negatively correlated with inflammatory biomarkers, supporting previous reports linking inflammation to reduced brain volumes in other neurological conditions. In the right hemisphere, we found negative correlations between HIA and BDNF, suggesting a neuroprotective function for BDNF in this neurodegenerative disease. These findings in a representative sample of patients with MS highlight the need for further research exploring the relationship between HIA and systemic serum biomarkers in MS.

U-fiber diffusion kurtosis and susceptibility characteristics in relapsing-remitting multiple sclerosis may be related to cognitive deficits and neurodegeneration.

To evaluate the diffusion kurtosis and susceptibility change in the U-fiber region of patients with relapsing-remitting multiple sclerosis (pwRRMS) and their correlations with cognitive status and degeneration. Mean kurtosis (MK), axial kurtosis (AK), radial kurtosis (RK), kurtosis fractional anisotropy (KFA), and the mean relative quantitative susceptibility mapping (mrQSM) values in the U-fiber region were compared between 49 pwRRMS and 48 healthy controls (HCs). The U-fiber were divided into upper and deeper groups based on the location. The whole brain volume, gray and white matter volume, and cortical thickness were obtained. The correlations between the mrQSM values, DKI-derived metrics in the U-fiber region and clinical scale scores, brain morphologic parameters were further investigated. The decreased MK, AK, RK, KFA, and increased mrQSM values in U-fiber lesions (p < 0.001, FDR corrected), decreased RK, KFA, and increased mrQSM values in U-fiber non-lesions (p = 0.034, p < 0.001, p < 0.001, FDR corrected) were found in pwRRMS. There were differences in DKI-derived metrics and susceptibility values between the upper U-fiber region and the deeper one for U-fiber non-lesion areas of pwRRMS and HCs (p < 0.05), but not for U-fiber lesions in DKI-derived metrics. The DKI-derived metrics and susceptibility values were widely related with cognitive tests and brain atrophy. RRMS patients show abnormal diffusion kurtosis and susceptibility characteristics in the U-fiber region, and these underlying tissue abnormalities are correlated with cognitive deficits and degeneration. The macroscopic and microscopic tissue damages of U-fiber help to identify cognitive impairment and brain atrophy in multiple sclerosis and provide underlying pathophysiological mechanism. • Diffusion kurtosis and susceptibility changes are present in the U-fiber region of multiple sclerosis. • There are gradients in diffusion kurtosis and susceptibility characteristics in the U-fiber region. • Tissue damages in the U-fiber region are correlated with cognitive impairment and brain atrophy.

Reliability of brain atrophy measurements in multiple sclerosis using MRI: an assessment of six freely available software packages for cross-sectional analyses.

Volume measurement using MRI is important to assess brain atrophy in multiple sclerosis (MS). However, differences between scanners, acquisition protocols, and analysis software introduce unwanted variability of volumes. To quantify theses effects, we compared within-scanner repeatability and between-scanner reproducibility of three different MR scanners for six brain segmentation methods. Twenty-one people with MS underwent scanning and rescanning on three 3T MR scanners (GE MR750, Philips Ingenuity, Toshiba Vantage Titan) to obtain 3D T1-weighted images. FreeSurfer, FSL, SAMSEG, FastSurfer, CAT-12, and SynthSeg were used to quantify brain, white matterand (deep) gray matter volumes both from lesion-filled and non-lesion-filled 3D T1-weighted images. We used intra-class correlation coefficient (ICC) to quantify agreement; repeated-measures ANOVA to analyze systematic differences; and variance component analysis to quantify the standard error of measurement (SEM) and smallest detectable change (SDC). For all six software, both between-scanner agreement (ICCs ranging 0.4-1) and within-scanner agreement (ICC range: 0.6-1) were typically good, and good to excellent (ICC > 0.7) for large structures. No clear differences were found between filled and non-filled images. However, gray and white matter volumes did differ systematically between scanners for all software (p < 0.05). Variance component analysis yielded within-scanner SDC ranging from 1.02% (SAMSEG, whole-brain) to 14.55% (FreeSurfer, CSF); and between-scanner SDC ranging from 4.83% (SynthSeg, thalamus) to 29.25% (CAT12, thalamus). Volume measurements of brain, GM and WM showed high repeatability, and high reproducibility despite substantial differences between scanners. Smallest detectable change was high, especially between different scanners, which hampers the clinical implementation of atrophy measurements.

Feasibility of detecting atrophy relevant for disability and cognition in multiple sclerosis using 3D-FLAIR.

Disability and cognitive impairment are known to be related to brain atrophy in multiple sclerosis (MS), but 3D-T1 imaging required for brain volumetrics is often unavailable in clinical protocols, unlike 3D-FLAIR. Here our aim was to investigate whether brain volumes derived from 3D-FLAIR images result in similar associations with disability and cognition in MS as do those derived from 3D-T1 images. 3T-MRI scans of 329 MS patients and 76 healthy controls were included in this cross-sectional study. Brain volumes were derived using FreeSurfer on 3D-T1 and compared with brain volumes derived with SynthSeg and SAMSEG on 3D-FLAIR. Relative agreement was evaluated by calculating the intraclass correlation coefficient (ICC) of the 3D-T1 and 3D-FLAIR volumes. Consistency of relations with disability and average cognition was assessed using linear regression, while correcting for age and sex. The findings were corroborated in an independent validation cohort of 125 MS patients. The ICC between volume measured with FreeSurfer and those measured on 3D-FLAIR for brain, ventricle, cortex, total deep gray matter and thalamus was above 0.74 for SAMSEG and above 0.91 for SynthSeg. Worse disability and lower average cognition were similarly associated with brain (adj. R2 = 0.24-0.27, p < 0.01; adj.R2 = 0.26-0.29, p < 0.001) ventricle (adj. R2 = 0.27-0.28, p < 0.001; adj. R2 = 0.19-0.20, p < 0.001) and deep gray matter volumes (adj. R2 = 0.24-0.28, p < 0.001; adj.R2 = 0.27-0.28, p < 0.001) determined with all methods, except for cortical volumes derived from 3D-FLAIR. In this cross-sectional study, brain volumes derived from 3D-FLAIR and 3D-T1 show similar relationships to disability and cognitive dysfunction in MS, highlighting the potential of these techniques in clinical datasets.

Enlarged choroid plexus related to iron rim lesions and deep gray matter atrophy in relapsing-remitting multiple sclerosis.

Choroid plexus (CP) is considered to be linked to inflammation of multiple sclerosis (MS), but its connection with markers of inflammation in vivo in MS is unclear, the markers such as lesions load and brain atrophy, particularly the white matter lesions (WMLs) edge surrounded by an iron rim, termed as iron rim lesions (IRLs). To investigate the association between CP volume and brain lesions load, especially IRLs load and atrophy in MS, and its relationship with clinical characteristics. 3.0 T brain MRI images were acquired from 99 relapsing-remitting MS (RRMS) and 60 healthy controls (HCs) to obtain the volumes of CP, whole brain and lesions. Volumes were expressed as a ratio of intracranial volume. Expanded Disability Status Scale (EDSS), Montreal Cognitive Assessment (MoCA) and Symbol Digit Modalities Test (SDMT) were used to assess the severity of disability and cognitive function. Student's t-test and Multivariable regression analyses were performed to evaluate the difference of CP volumes between RRMS and HC and the association between CP volume and lesions load, brain volumes and clinical scale scores in RRMS. CP volume was 30% larger in patients with RRMS than HCs (p < 0.001) and was 20% larger in patients with IRLs than those without IRLs (p=0.007). Moreover, the larger CP volume was related to greater WMLs volume in the whole RRMS (r=0.46, p < 0.001). Further analysis in patients with IRLs showed a positive correlation between CP volume and WMLs volume (r=0.45, p=0.003), and IRLs volume (r=0.51, p < 0.001). Meanwhile, enlarged CP was related to lower volumes in the whole brain (r=-0.30, p=0.006), deep gray matter (r=-0.51, p < 0.001) and most regional deep gray matter nuclei (except amygdala), but no correlation with cortical lesions or cortex volume (both p > 0.05). In addition, CP volume was significantly higher in patients with cognitive impairment than those with cognitive preservation by MoCA scores (p=0.011); the larger CP volume was associated with higher EDSS scores (r=0.25, p=0.014) and lower SDMT Z scores in RRMS (r=-0.26, p=0.014). The enlargement of CP in RRMS had close correlations with inflammatory lesions, especially IRLs and deep gray matter atrophy, but not the cortex. Meanwhile, the larger CP volume was associated with higher disability and lower cognitive scores. CP volume may be a surrogate imaging marker for MS disease activity.

The impact of cigarette smoking on cognitive processing speed and brain atrophy in multiple sclerosis

Background: Smoking is associated with an increased risk of multiple sclerosis (MS) and disability worsening. The relationship between smoking, cognitive processing speed, and brain atrophy remains uncertain. Objective: To quantify the impact of smoking on processing speed and brain volume in MS and to explore the longitudinal relationship between smoking and changes in processing speed. Methods: A retrospective study of MS patients who completed the processing speed test (PST) between September 2015 and March 2020. Demographics, disease characteristics, smoking history, and quantitative magnetic resonance imaging (MRI) were collected. Cross-sectional associations between smoking, PST performance, whole-brain fraction (WBF), gray matter fraction (GMF), and thalamic fraction (TF) were assessed using multivariable linear regression. The longitudinal relationship between smoking and PST performance was assessed by linear mixed modeling. Results: The analysis included 5536 subjects of whom 1314 had quantitative MRI within 90 days of PST assessment. Current smokers had lower PST scores than never smokers at baseline, and this difference persisted over time. Smoking was associated with reduced GMF but not with WBF or TF. Conclusion: Smoking has an adverse relationship with cognition and GMF. Although causality is not demonstrated, these observations support the importance of smoking cessation counseling in MS management.

Third Ventricle Width is a Reliable and Clinically-Feasible Marker of Brain Atrophy in the Multiple Sclerosis Clinical Care Setting (P10-3.003)

<h3>Objective:</h3> Examine reliability and clinical utility of third ventricle width (TVW) on standard-of-care MRIs as a marker of cerebral atrophy in real-world multiple sclerosis (MS) clinical care settings. <h3>Background:</h3> Cerebral atrophy is emerging as an important marker of MS disease progression, but clinically-feasible volumetric measurements remain elusive in clinical care settings. Research supports TVW as a reliable, valid, fast, and easy manual two-dimensional MRI estimate of cerebral atrophy that correlates with clinical disability and tracks with volumetric changes. Importantly, most TVW research has utilized standardized research MRIs; it is unclear how findings translate to standard-of-care (SoC) MRIs (i.e., variable field strengths and sequence parameters). We evaluated real-world clinical utility by examining reliability and clinical relevance of TVW measured from SoC (i.e., clinical) MRIs. <h3>Design/Methods:</h3> We measured TVW from SoC brain MRIs in 563 consecutive patients aged 18–65 years. Three trained raters blind to other patient data measured TVW in millimeters from midpoints of left and right boundaries of the third ventricle in axial T1-weighted images. TVWs were adjusted for demographic characteristics. Disability was assessed with the gold-standard MS Functional Composite (MSFC) evaluating cognition (SDMT), upper extremity coordination (NHPT), and gait (T25FW). GLM assessed TVW differences across level of level of impairment (number of MSFC components &lt;5^th percentile). <h3>Results:</h3> Interrater reliability of TVW measurement indicated excellent absolute-agreement (two-way mixed effects ICCs: single-rating 0.982; 95%CI: 0.958, 0.994; mean-rating <i>k</i>=3, 0.994; 0.986, 0.998). Medium-to-large difference in TVW across MSFC impairment (<i>p</i> for trend &lt;0.001; η_p²=0.089): TVW (mean [95%CI]) increased across patients impaired on no (n=245; 3.34 [3.14, 3.54]), one (n=155; 3.74 [3.45, 3.99]), two (n=106; 4.30 [4.00, 4.60]), and three (n=57; 4.81 [4.40, 5.22]) MSFC tasks. <h3>Conclusions:</h3> Measurement of TVW from standard-of-care MRIs is a highly-reliable and clinically-relevant marker of brain atrophy in MS that can be easily implemented into routine clinical care. <b>Disclosure:</b> Dr. Levy has nothing to disclose. Dr. Patel has nothing to disclose. Mr. Sumowski has nothing to disclose.

Gray Matter Microstructure Alterations in People with Multiple Sclerosis Based on Cell Body and Neurite Density Imaging (P10-3.007)

<h3>Objective:</h3> To evaluate a novel compartment-based model for apparent cell body and neurite density imaging (SANDI) in gray matter (GM) in people with multiple sclerosis (MS) compared to healthy controls (HC) and its correlation with brain atrophy. <h3>Background:</h3> MS features focal cortical lesions and microstructural changes in normal-appearing GM, which can impact clinical function and disability. High gradient diffusion MRI has potential to optimize GM tissue microstructure characterization by overcoming challenges due to the complexity of underlying components. <h3>Design/Methods:</h3> 41 people with MS and 37 age- and sex-matched HC were scanned on a 3T Connectom MRI scanner equipped with 300mT/m gradients using a multi-shell acquisition protocol consisting of eight b-values at 19msec diffusion time. Microstructural metrics of SANDI, including a measure of soma density (f_soma) in the cortex and deep GM, were compared between MS and HC and correlated with cortical and thalamic atrophy, correcting for multiple comparisons. <h3>Results:</h3> Cortical cell body signal fraction (f_soma) was decreased in MS compared to HC (0.56 vs. 0.58, <i>p</i>=0.027, not surviving FDR-correction). In deep GM, f_soma and extra-cellular signal fraction were significantly decreased in MS compared to HC (<i>FDR-p</i>=0.045 in both), which was most pronounced in progressive MS. Based on spatial analysis, f_soma of caudate nucleus and thalamus were significantly decreased in MS compared to HC (<i>FDR-p</i>=0.003 and <i>FDR-p</i>=0.027, respectively). Whereas cortical atrophy in MS was poorly correlated with cortical f_soma, thalamic atrophy in MS demonstrated moderate correlation with decreased thalamic f_soma (r=0.311, <i>p</i>=0.054) and decreased cortical f_soma (r=0.474, <i>p</i>=0.008). <h3>Conclusions:</h3> SANDI metrics, in particular f_soma, provide detailed GM characterization beyond cortical and thalamic volumes and are able to characterize MS-related microstructural pathology. Decreased cortical cell density correlates with declining thalamic volume and may precede volumetric measures of cortical atrophy in people with MS. <b>Disclosure:</b> Ms. Krijnen has nothing to disclose. Andrew Russo has nothing to disclose. Dr. Salim Karam has nothing to disclose. The institution of Menno M Schoonheim has received research support from Dutch MS Research Foundation. The institution of Menno M Schoonheim has received research support from Eurostars-EUREKA. The institution of Menno M Schoonheim has received research support from ARSEP. The institution of Menno M Schoonheim has received research support from Amsterdam Neuroscience. The institution of Menno M Schoonheim has received research support from MAGNIMS. The institution of Menno M Schoonheim has received research support from ZonMW. The institution of Menno M Schoonheim has received research support from Atara Biotherapeutics. The institution of Menno M Schoonheim has received research support from Biogen. The institution of Menno M Schoonheim has received research support from Celgene/Bristol Meyers Squibb. The institution of Menno M Schoonheim has received research support from Genzyme. The institution of Menno M Schoonheim has received research support from MedDay. The institution of Menno M Schoonheim has received research support from Merck. Dr. Huang has received personal compensation in the range of $0-$499 for serving as a Consultant for Siemens Healthineers. The institution of Dr. Huang has received research support from Siemens Healthineers. The institution of Dr. Huang has received research support from Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School. Dr. Klawiter has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Galen/Atlantica. Dr. Klawiter has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Genentech. Dr. Klawiter has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Banner Life Sciences. Dr. Klawiter has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Greenwich Biosciences. Dr. Klawiter has received personal compensation in the range of $10,000-$49,999 for serving on a Scientific Advisory or Data Safety Monitoring board for OM1. Dr. Klawiter has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for TG Therapeutics. The institution of Dr. Klawiter has received research support from Biogen. The institution of Dr. Klawiter has received research support from Abbvie. The institution of Dr. Klawiter has received research support from Genentech.

Longitudinal Brain Volume Findings in an Outpatient Practice of Young People with MS (P11-3.001)

<h3>Objective:</h3> To assess in an outpatient setting the application of volumetrics with brain MRI among young people with multiple sclerosis (MS). <h3>Background:</h3> Research on brain atrophy in MS has illuminated how inflammation and neurodegenerative processes lead to cognitive and neurologic declines. However, brain volume assessment is rarely used in routine practice. Here, we examined predominantly pediatric onset MS and some younger adult-onset MS patients who underwent routine brain MRI including volumetrics. Our goal was to assess the impact of brain volume change on clinical outcomes including SDMT in this relatively young and stable MS subset. <h3>Design/Methods:</h3> 77 patients with pediatric or adult onset RRMS or CIS, 31 years of age or younger, were evaluated with at least two MRI studies. Volume data was computed on MRI images with icobrain ms software, compared to age- and sex-related norms and adjusted for differences across the various Siemens 3T scanners. Changes in volumes of whole brain (WB), white matter (WM), grey matter (GM), lateral ventricles (LV), and thalamus were calculated as an average annualized percent brain volume change per year. <h3>Results:</h3> The mean patient age was 21.6 years (range 12–31); 70% were female. The annual mean decrease of WB volume: −0.473%, WM: −0.390%, GM: −0.517%, thalamus: −0.552%, and annual LV volume increase: 1.78%. A total of 32.5% of patients had an annual decrease in GM volume &gt;0.8% (the 90% threshold for measurement error). 29.9% of patients had LV volumes increase &gt;3.5%. Whole brain volume loss and lateral ventricle increase was significantly correlated, r=−0.34 (p=0.002). Clinical and demographic features between those whose brain volume declined and those whose brain volumes remained stable will be presented. <h3>Conclusions:</h3> Quantitative MRI is a useful technique which has only begun to be incorporated into clinical practice. A proportion of young otherwise stable patients with RRMS show brain volume loss under computer-assisted analyses. <b>Disclosure:</b> Dr. O’Neill has nothing to disclose. Dr. Couvreur has received personal compensation in the range of $10,000-$49,999 for serving as a Intern Clinical application specialist at icometrix with The Prince Albert Fund. Dr. Hu has nothing to disclose. Mr. Zhang has nothing to disclose. Ms. Pehel has nothing to disclose. Ms. Sosa has nothing to disclose. Ms. Fade has nothing to disclose. Elayne Feld has nothing to disclose. Dr. Chen has received personal compensation for serving as an employee of icometrix. Dr. De Barros has received personal compensation for serving as an employee of Icometrix. Thibo Billiet has received personal compensation for serving as an employee of icometrix. Annemie Ribbens, 9599 has received personal compensation for serving as an employee of icometrix. Annemie Ribbens, 9599 has stock in icometrix. Dr. Krupp has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Roche. Dr. Krupp has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Novartis. Dr. Krupp has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Janssen. Dr. Krupp has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Gerson Lerhman. Dr. Krupp has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for medscape. Dr. Krupp has received personal compensation in the range of $500-$4,999 for serving as a Consultant for NeuroLive. Dr. Krupp has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Eisai. Dr. Krupp has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Sanofi. Dr. Krupp has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Biogen. Dr. Krupp has received personal compensation in the range of $500-$4,999 for serving as an officer or member of the Board of Directors for Cleveland Clinic. Dr. Krupp has received personal compensation in the range of $500-$4,999 for serving as an Expert Witness for MCIC. The institution of Dr. Krupp has received research support from Biogen. The institution of Dr. Krupp has received research support from National Multiple Sclerosis Society. Dr. Krupp has received intellectual property interests from a discovery or technology relating to health care.

Clinical Relevance of Spatial Correspondence Between Regional Gene Expression and Gray Matter Atrophy in Multiple Sclerosis (S27.004)

Clinical Relevance of Spatial Correspondence Between Regional Gene Expression and Gray Matter Atrophy in Multiple Sclerosis (S27.004)

An Interpretable Machine Learning Model to Predict Cortical Atrophy in Multiple Sclerosis

To date, the relationship between central hallmarks of multiple sclerosis (MS), such as white matter (WM)/cortical demyelinated lesions and cortical gray matter atrophy, remains unclear. We investigated the interplay between cortical atrophy and individual lesion-type patterns that have recently emerged as new radiological markers of MS disease progression. We employed a machine learning model to predict mean cortical thinning in whole-brain and single hemispheres in 150 cortical regions using demographic and lesion-related characteristics, evaluated via an ultrahigh field (7 Tesla) MRI. We found that (i) volume and rimless (i.e., without a "rim" of iron-laden immune cells) WM lesions, patient age, and volume of intracortical lesions have the most predictive power; (ii) WM lesions are more important for prediction when their load is small, while cortical lesion load becomes more important as it increases; (iii) WM lesions play a greater role in the progression of atrophy during the latest stages of the disease. Our results highlight the intricacy of MS pathology across the whole brain. In turn, this calls for multivariate statistical analyses and mechanistic modeling techniques to understand the etiopathogenesis of lesions.

Enlarged choroid plexus related to cortical atrophy in multiple sclerosis.

To investigate the correlation between choroid plexus volume and whole brain morphology in patients with multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). Fifty-one patients with MS, 42 patients with NMOSD, and 56 healthy controls (HC) were recruited. The morphological changes in choroid plexus and whole brain tissue were compared between three groups and the correlations between choroid plexus volume and brain atrophy were further investigated. The longitudinal alterations of brain morphology in 25 MS and 20 NMOSD patients were compared. Compared to the HC group, the choroid plexus volumes were increased in the MS group (p < 0.001) but not in the NMOSD group (p > 0.05). Compared to the HC group, the MS group showed reduced cortex thickness, deep gray matter volume, and increased ventricle system volume, and the NMOSD group showed increased third ventricle volume (all p < 0.05, false discovery rate corrected). In the MS group, there were widespread correlations between enlarged choroid plexus volume and reduced cerebral cortex thickness (p < 0.05, r = -0.292~-0.538, false discovery rate corrected). The interval time was not significantly different between the MS (median: 1.37 years) and NMOSD group (median: 1.25 years) (p > 0.05). In MS, compared with the baseline, the right hippocampus and nucleus accumbens volumes were decreased in long follow-up, and bilateral lateral ventricle volumes were increased both in short and long follow-up (all p < 0.05, false discovery rate corrected). The enlarged choroid plexus related to reduced cortical thickness and progressive local brain atrophy are shown in MS patients, but not obvious in NMOSD patients. • MS and NMOSD have different altered patterns in choroid plexus volume and brain atrophy. • The enlarged choroid plexus related to brain atrophy is shown in MS patients, but not obvious in NMOSD patients. • Progressive local brain atrophy is shown in MS patients, but not obvious in NMOSD patients.

Percentage brain volume change in multiple sclerosis mainly reflects white matter and cortical volume.

Brain atrophy in multiple sclerosis (MS), as measured by percentage brain volume change (PBVC) from brain magnetic resonance imaging (MRI), has been established as an outcome parameter in clinical trials. It is unknown to what extent volume changes within different brain tissue compartments contribute to PBVC. We analyzed pairs of MRI scans (at least 6 months apart) in 600 patients with relapsing-remitting MS. Multiple regression revealed that PBVC mainly reflects volume loss of white and cortical gray matter, while deep gray matter and white matter lesions were less represented. Our findings aid the interpretation of PBVC changes in MS.

Clinical correlates of R1 relaxometry and magnetic susceptibility changes in multiple sclerosis: a multi-parameter quantitative MRI study of brain iron and myelin

ObjectivesThe clinical impact of brain microstructural abnormalities in multiple sclerosis (MS) remains elusive. We aimed to characterize the topography of longitudinal relaxation rate (R1) and quantitative susceptibility (χ) changes, as indices of iron and myelin, together with brain atrophy, and to clarify their contribution to cognitive and motor disability in MS.MethodsIn this cross-sectional study, voxel-based morphometry, and voxel-based quantification analyses of R1 and χ maps were conducted in gray matter (GM) and white matter (WM) of 117 MS patients and 53 healthy controls. Voxel-wise between-group differences were assessed with nonparametric permutation tests, while correlations between MRI metrics and clinical variables (global disability, cognitive and motor performance) were assessed both globally and voxel-wise within clusters emerging from the between-group comparisons.ResultsMS patients showed widespread R1 decrease associated with more limited modifications of χ, with atrophy mainly involving deep GM, posterior and infratentorial regions (p < 0.02). While R1 and χ showed a parallel reduction in several WM tracts (p < 0.001), reduced GM R1 values (p < 0.001) were associated with decreased thalamic χ (p < 0.001) and small clusters of increased χ in the caudate nucleus and prefrontal cortex (p < 0.02). In addition to the atrophy, χ values in the cingulum and corona radiata correlated with global disability and motor performance, while focal demyelination correlated with cognitive performance (p < 0.04).ConclusionsWe confirmed the presence of widespread R1 changes, involving both GM and WM, and atrophy in MS, with less extensive modifications of tissue χ. While atrophy and χ changes are related to global and motor disability, R1 changes are meaningful correlates of cognition.Key Points• Compared to healthy controls, multiple sclerosis patients showed R1 and χ changes suggestive of iron increase within the basal ganglia and reduced iron and myelin content within (subnuclei of) the thalamus.• Thalamic volume and χ changes significantly predicted clinical disability, as well as pulvinar R1 and χ changes, independently from atrophy.• Atrophy-independent R1 and χ changes, suggestive of thalamic iron and myelin depletion, may represent a sensitive marker of subclinical inflammation.

Confounder-adjusted MRI-based predictors of multiple sclerosis disability.

Both aging and multiple sclerosis (MS) cause central nervous system (CNS) atrophy. Excess brain atrophy in MS has been interpreted as "accelerated aging." Current paper tests an alternative hypothesis: MS causes CNS atrophy by mechanism(s) different from physiological aging. Thus, subtracting effects of physiological confounders on CNS structures would isolate MS-specific effects. Standardized brain MRI and neurological examination were acquired prospectively in 646 participants enrolled in ClinicalTrials.gov Identifier: NCT00794352 protocol. CNS volumes were measured retrospectively, by automated Lesion-TOADS algorithm and by Spinal Cord Toolbox, in a blinded fashion. Physiological confounders identified in 80 healthy volunteers were regressed out by stepwise multiple linear regression. MS specificity of confounder-adjusted MRI features was assessed in non-MS cohort (n = 158). MS patients were randomly split into training (n = 277) and validation (n = 131) cohorts. Gradient boosting machine (GBM) models were generated in MS training cohort from unadjusted and confounder-adjusted CNS volumes against four disability scales. Confounder adjustment highlighted MS-specific progressive loss of CNS white matter. GBM model performance decreased substantially from training to cross-validation, to independent validation cohorts, but all models predicted cognitive and physical disability with low p-values and effect sizes that outperform published literature based on recent meta-analysis. Models built from confounder-adjusted MRI predictors outperformed models from unadjusted predictors in the validation cohort. GBM models from confounder-adjusted volumetric MRI features reflect MS-specific CNS injury, and due to stronger correlation with clinical outcomes compared to brain atrophy these models should be explored in future MS clinical trials.

Mechanisms of central brain atrophy in multiple sclerosis

Background: Change in ventricular volume has been suggested as surrogate measure of central brain atrophy (CBA) applicable to the everyday management of multiple sclerosis (MS) patients. Objectives: We investigated the contribution of inflammatory activity (including the severity of lesional tissue damage) to CBA. Methods: Fifty patients with relapsing–remitting multiple sclerosis (RRMS) were enrolled. Lesional activity during 4 years of follow-up was analysed using custom-build software, which segmented expanding part of the chronic lesions, new confluent lesions and new free-standing lesions. The degree of lesional tissue damage was assessed by change in mean diffusivity (MD). Volumetric change of lateral ventricles was used to measure CBA. Results: During follow-up, ventricles expanded on average by 12.6% ± 13.7% (mean ± SD). There was a significant increase of total lesion volume, 69.3% of which was due to expansion of chronic lesions. Correlation between volume of combined lesional activity and CBA (r2 = 0.67) increased when lesion volume was adjusted by the degree of tissue damage severity (r2 = 0.81). Regression analysis explained 90% of CBA variability, revealing that chronic lesion expansion was by far the largest contributor to ventricular enlargement. Discussion: CBA is almost entirely explained by the combination of the volume and severity of lesional activity. The expansion of chronic lesions plays a central role in this process.

An accurate spinal cord partition and quantification method to monitor atrophy in multiple sclerosis

An accurate spinal cord partition and quantification method to monitor atrophy in multiple sclerosis