The impact of cervical spinal cord atrophy on quality of life in multiple sclerosis

The correlation between 9-HPT and patient-reported measures of upper limb function in multiple sclerosis: a systematic review and meta-analysis

Upper limb function is one of the most affected domains in people with multiple sclerosis (PwMS), as self-reported by 50% of patients. Heterogeneous results have been found about the correlation between objective and subjective upper limb function. The aim of the present study is to perform a systematic review and meta-analysis of studies presenting data on the strength of association between the gold standard for 9-Hole Peg Test scores and Patient-Reported Outcome Measures (PROMs) of manual ability. Primary research studies including assessments of 9-Hole Peg Test scores and Patient-Reported Outcome Measures were searched in Scopus, Web of Science, and PubMed. Meta analytical calculations were performed using a random-effects model. We retrieved n = 27 studies including n = 75 distinct effect sizes (N of subjects = 3263). The central tendency analysis showed a strong correlation between 9-HPT scores and PROMs (r = 0.51, 95% CI [0.44, 0.58]). Moderator analysis showed the effect size to be significantly larger in studies with a mean or median EDSS level indicating severe disability. The publication bias hypothesis was not supported; instead, we noted that studies based on larger samples also tend to report stronger effect sizes. Results of the study indicate that the correlation between 9-HPT and PROMs is strong, although the constructs measured by these instrument does not fully overlap. The correlation between 9-HPT and PROMs was stronger in larger studies and when samples include a sizeable subgroup of PwMS with severe disability, pointing out the importance of sample diversity.

Recent Progress in the Identification of Early Transition Biomarkers from Relapsing-Remitting to Progressive Multiple Sclerosis

Despite extensive research into the pathophysiology of multiple sclerosis (MS) and recent developments in potent disease-modifying therapies (DMTs), two-thirds of relapsing-remitting MS patients transition to progressive MS (PMS). The main pathogenic mechanism in PMS is represented not by inflammation but by neurodegeneration, which leads to irreversible neurological disability. For this reason, this transition represents a critical factor for the long-term prognosis. Currently, the diagnosis of PMS can only be established retrospectively based on the progressive worsening of the disability over a period of at least 6 months. In some cases, the diagnosis of PMS is delayed for up to 3 years. With the approval of highly effective DMTs, some with proven effects on neurodegeneration, there is an urgent need for reliable biomarkers to identify this transition phase early and to select patients at a high risk of conversion to PMS. The purpose of this review is to discuss the progress made in the last decade in an attempt to find such a biomarker in the molecular field (serum and cerebrospinal fluid) between the magnetic resonance imaging parameters and optical coherence tomography measures.

Neuroimaging Correlates of Patient-Reported Outcomes in Multiple Sclerosis

Background

Patient-reported outcomes (PROs) are increasingly associated with concurrent and future impairments in persons with multiple sclerosis (pwMS). The structural and pathological relationships with PROs in pwMS have not been elucidated.

Methods

One hundred and forty-two pwMS and 47 healthy controls (HCs) were scanned using 3T MRI and completed a PRO questionnaire named Lifeware^® that outlines the physical and psychosocial abilities. Beck's Depression Inventory (BDI) assessed levels of depression. T1- and T2-lesion volume, volumes of the whole brain (WBV), gray matter (GMV), white matter (WMV) and lateral ventricle (LVV) were derived using JIM and SIENAX software. Additional deep GM (DGMV) and nuclei-specific volumes of the thalamus, caudate, globus pallidus, putamen, and hippocampus were calculated using FIRST. Ordinal regression models adjusted for age and depression and mediation analyses were used.

Results

When compared to HCs, pwMS reported significantly greater limitations in mobility domains, including standing up from low seat (p < 0.001), climbing flight of stairs (p < 0.001), lower limb limitation (p < 0.001), limitations in bladder continence (p = 0.001) and fatigability (p < 0.001). Patient-reported limitations related to lower extremity function were explained by age, BDI, and all DGM nuclei volumes (p < 0.029). No such relationships were seen in the HCs. Fatiguability and the extent of life satisfaction were only related to depression (BDI p < 0.001) and not associated with any MRI-based outcomes. Most relationships between structural pathology and PROs were mediated by BDI scores (p < 0.001). In the pwMS group, there were no significant differences in any MRI-based brain volumes between the levels of reported life satisfaction.

Conclusion

PRO measures of lower extremity limitations were associated with DGM structures and DGM-specific nuclei. These findings promote the relevance of measuring DGM structures as measures directly related to subjective well-being and walking limitations. Depression is a significant mediator of PROs and in particular of life satisfaction.

Spinal cord reserve in multiple sclerosis

BACKGROUND

The spinal cord (SC) is a preferential target of multiple sclerosis (MS) damage highly relevant towards disability. Differential impact of such damage could be due to the initial amount of SC tissue, as described for the brain parenchyma (brain reserve concept). We aimed to test the existence of SC reserve by using spinal canal area (SCaA) as a proxy.

METHODS

Brain sagittal three-dimensional T1-weighted scans covering down to C5 level were acquired in 2930 people with MS and 43 healthy controls (HCs) in a cross-sectional, multicentre study. SC area (SCA) and SCaA were obtained with the Spinal Cord Toolbox. Demographical data and patient-derived disability scores were obtained. SC parameters were compared between groups with age-adjusted and sex-adjusted linear regression models. The main outcome of the study, the existence of an association between SCaA and Patient Determined Disease Steps, was tested with scaled linear models.

RESULTS

1747 persons with MS (mean age: 46.35 years; 73.2% female) and 42 HCs (mean age: 45.56 years; 78.6% female) were analysed after exclusion of post-processing errors and application of quality criteria. SCA (60.41 mm² vs 65.02 mm², p<0.001) was lower in people with MS compared with HC; no differences in SCaA were observed (213.24 mm² vs 212.61 mm², p=0.125). Adjusted scaled linear models showed that a larger SCaA was significantly associated with lower scores on Patient Determined Disease Steps (beta coefficient: -0.12, p=0.0124) independently of spinal cord atrophy, brain T2 lesion volume, age and sex.

CONCLUSIONS

A larger SCaA may be protective against disability in MS, possibly supporting the existence of SC reserve.

The course of cervical spinal cord atrophy rate and its relationship with NEDA in relapsing remitting multiple sclerosis

This study aimed to compare the annualized segmental cervical spinal cord atrophy rate (ASCAR) in the early and late stages of relapsing remitting multiple sclerosis (RRMS), and to investigate the relationship between ASCAR and no evidence of disease activity (NEDA) in RRMS. Participants in this study included early stage MS (EMSg) patients, late stage MS (LMSg) patients, and healthy controls. All of the included participants (n = 175 subjects) were followed up for 14 months, and an MRI was performed on each participant at the beginning and at the end of the study. Cervical spinal cord average segmental area (CSCA) was measured by a semi-automated method, and ASCAR (mm²/year) was calculated. Data from the EMSg (n = 81 subjects) and LMSg (n = 94 subjects) patient groups were compared with each other and with the control group (n = 43 subjects). Examination of the initial CSCA values revealed that the baseline CSCA of the control group was larger than that of the EMSg (p < 0.001), and the baseline CSCA of the EMSg was larger than that of the LMSg (p < 0.001). The ASCAR of the control group, LMSg, and EMSg were 0.48, 0.93, and 1.81 mm² (p < 0.001), respectively. Regression analysis revealed that disability increase was associated with ASCAR, while MRI activity and relapse presence were unrelated to ASCAR. In both patient groups, ASCAR was slower in those who fulfilled NEDA but this relationship was not significant. Cervical spinal cord atrophy progression over time occurs at a greater rate in the early stages of RRMS disease compared to the late stages. ASCAR was unrelated to MRI activity and relapse, which are clinical markers of acute inflammation.

Upper cervical cord atrophy is independent of cervical cord lesion volume in early multiple sclerosis: A two-year longitudinal study

BACKGROUND

Upper cervical cord atrophy and lesions have been shown to be associated with disease and disability progression already in early relapsing-remitting multiple sclerosis (RRMS). However, their longitudinal relationship remains unclear.

OBJECTIVE

To investigate the cross-sectional and longitudinal relation between focal T2 cervical cord lesion volume (CCLV) and regional and global mean upper cervical cord area (UCCA), and their relations with disability.

METHODS

Over a two-year interval, subjects with RRMS (n = 36) and healthy controls (HC, n = 16) underwent annual clinical and MRI examinations. UCCA and CCLV were obtained from C1 through C4 level. Linear mixed model analysis was performed to investigate the relation between UCCA, CCLV, and disability over time.

RESULTS

UCCA at baseline was significantly lower in RRMS subjects compared to HCs (p = 0.003), but did not decrease faster over time (p ≥ 0.144). UCCA and CCLV were independent of each other at any of the time points or cervical levels, and over time. Lower baseline UCCA, but not CCLV, was related to worsening of both upper and lower extremities function over time.

CONCLUSION

UCCA and CCLV are independent from each other, both cross-sectionally and longitudinally, in early MS. Lower UCCA, but not CCLV, was related to increasing disability over time.

Cervical Spinal Cord Atrophy can be Accurately Quantified Using Head Images

Background

Spinal cord atrophy provides a clinically relevant metric for monitoring MS. However, the spinal cord is imaged far less frequently than brain due to artefacts and acquisition time, whereas MRI of the brain is routinely performed.

Objective

To validate spinal cord cross-sectional area measurements from routine 3DT1 whole-brain MRI versus those from dedicated cord MRI in healthy controls and people with MS.

Methods

We calculated cross-sectional area at C1 and C2/3 using T2*-weighted spinal cord images and 3DT1 brain images, for 28 healthy controls and 73 people with MS. Correlations for both groups were assessed between: (1) C1 and C2/3 using cord images; (2) C1 from brain and C1 from cord; and (3) C1 from brain and C2/3 from cord.

Results and Conclusion

C1 and C2/3 from cord were strongly correlated in controls (r = 0.94, p<0.0001) and MS (r = 0.85, p<0.0001). There was strong agreement between C1 from brain and C2/3 from cord in controls (r = 0.84, p<0.0001) and MS (r = 0.81, p<0.0001). This supports the use of C1 cross-sectional area calculated from brain imaging as a surrogate for the traditional C2/3 cross-sectional area measure for spinal cord atrophy.

Ultra-high field spinal cord MRI in multiple sclerosis: Where are we standing? A literature review

Magnetic resonance imaging (MRI) is a cornerstone in multiple sclerosis (MS) diagnostics and monitoring. Ultra-high field (UHF) MRI is being increasingly used and becoming more accessible. Due to the small diameter and mobility of the spinal cord, imaging this structure at ultra-high fields poses additional challenges compared to brain imaging. Here we review the potential benefits for the MS field by providing a literature overview of the use UHF spinal cord MRI in MS research and we elaborate on the challenges that are faced. Benefits include increased signal- and contrast-to-noise, enabling for higher spatial resolutions, which can improve MS lesion sensitivity in both the spinal white matter as well as grey matter. Additionally, these benefits can aid imaging of microstructural abnormalities in the spinal cord in MS using advanced MRI techniques like functional imaging, MR spectroscopy and diffusion-based techniques. Technical challenges include increased magnetic field inhomogeneities, distortions from physiological motion and optimalisation of sequences. Approaches including parallel imaging techniques, real time shimming and retrospective compensation of physiological motion are making it increasingly possible to unravel the potential of spinal cord UHF MRI in the context of MS research.

Cervical and thoracic cord atrophy in multiple sclerosis phenotypes: Quantification and correlation with clinical disability

•

Spinal cord atrophy is prevalent across multiple sclerosis phenotypes.

•

It correlates with disability, especially in relapsing-remitting patients.

•

This correlation can be demonstrated both cross-sectionally and longitudinally.

•

Cervical atrophy is highly associated with disability and disease progression.

•

Thoracic atrophy contributes to improved correlation and radiological subgrouping.

Objective

We sought to characterize spinal cord atrophy along the entire spinal cord in the major multiple sclerosis (MS) phenotypes, and evaluate its correlation with clinical disability.

Methods

Axial T₁-weighted images were automatically reformatted at each point along the cord. Spinal cord cross‐sectional area (SCCSA) were calculated from C1-T10 vertebral body levels and profile plots were compared across phenotypes. Average values from C2-3, C4-5, and T4-9 regions were compared across phenotypes and correlated with clinical scores, and then categorized as atrophic/normal based on z-scores derived from controls, to compare clinical scores between subgroups. In a subset of relapsing-remitting cases with longitudinal scans these regions were compared to change in clinical scores.

Results

The cross-sectional study consisted of 149 adults diagnosed with relapsing-remitting MS (RRMS), 49 with secondary-progressive MS (SPMS), 58 with primary-progressive MS (PPMS) and 48 controls. The longitudinal study included 78 RRMS cases. Compared to controls, all MS groups had smaller average regions except RRMS in T4-9 region. In all MS groups, SCCSA from all regions, particularly the cervical cord, correlated with most clinical measures. In the RRMS cohort, 22% of cases had at least one atrophic region, whereas in progressive MS the rate was almost 70%. Longitudinal analysis showed correlation between clinical disability and cervical cord thinning.

Conclusions

Spinal cord atrophy was prevalent across MS phenotypes, with regional measures from the RRMS cohort and the progressive cohort, including SPMS and PPMS, being correlated with disability. Longitudinal changes in the spinal cord were documented in RRMS cases, making it a potential marker for disease progression. While cervical SCCSA correlated with most disability and progression measures, inclusion of thoracic measurements improved this correlation and allowed for better subgrouping of spinal cord phenotypes. Cord atrophy is an important and easily obtainable imaging marker of clinical and sub-clinical progression in all MS phenotypes, and such measures can play a key role in patient selection for clinical trials.

Assessment of Racial/Ethnic Disparities in Volumetric MRI Correlates of Clinical Disability in Multiple Sclerosis: A Preliminary Study

BACKGROUND AND PURPOSE

Although global and regional brain volume has been established as a relevant measure to define and predict multiple sclerosis (MS) severity, characterization of specific trends by race/ethnicity is currently lacking. We aim to (1) characterize racial disparities in disability-specific patterns of brain MRI volumetric measures between Hispanic and Caucasian individuals with MS and (2) explore the relevance of these measures as predictors of clinical disability progression.

METHODS

Brain MRI scans from 94 Hispanic and 94 age- and gender-matched Caucasian MS patients were analyzed using automatic and manual segmentation techniques. Select global and regional volume measures were correlated to Expanded Disability Status Scale (EDSS) scores at baseline and subsequent follow-up visits.

RESULTS

Hispanic patients had a higher baseline median EDSS score (interquartile range [IQR], 2.0; [1.0-3.5]) compared to Caucasians (median [IQR], 1.0 [.0-2.0]) and an increased risk of requiring ambulatory assistance (hazard ratio [HR], 9.7; 95% confidence interval [CI], 2.8-32.5). Normalized thalamic volume was moderately associated with EDSS scores (r_s   = -.42,  P < .001 in Hispanics; r_s   = -.32, P  = .002 in Caucasians) and was the best predictor of sustained disability worsening in both racial groups in a time-to-event analysis.

CONCLUSIONS

The confounding impact of race on quantitative brain volume measures may affect the interpretation of outcome measures in MS clinical trials.

Spinal cord atrophy as a measure of severity of myelopathy in adrenoleukodystrophy

All men and most women with X-linked adrenoleukodystrophy (ALD) develop myelopathy in adulthood. As clinical trials with new potential disease-modifying therapies are emerging, sensitive outcome measures for quantifying myelopathy are needed. This prospective cohort study evaluated spinal cord size (cross-sectional area - CSA) and shape (eccentricity) as potential new quantitative outcome measures for myelopathy in ALD. Seventy-four baseline magnetic resonance imaging (MRI) scans, acquired in 42 male ALD patients and 32 age-matched healthy controls, and 26 follow-up scans of ALD patients were included in the study. We used routine T1 -weighted MRI sequences to measure mean CSA, eccentricity, right-left and anteroposterior diameters in the cervical spinal cord. We compared MRI measurements between groups and correlated CSA with clinical outcome measures of disease severity. Longitudinally, we compared MRI measurements between baseline and 1-year follow-up. CSA was significantly smaller in patients compared to controls on all measured spinal cord levels (P < .001). The difference was completely explained by the effect of the symptomatic subgroup. Furthermore, the spinal cord showed flattening (higher eccentricity and smaller anteroposterior diameters) in patients. CSA correlated strongly with all clinical measures of severity of myelopathy. There was no detectable change in CSA after 1-year follow-up. The cervical spinal cord in symptomatic ALD patients is smaller and flattened compared to controls, possibly due to atrophy of the dorsal columns. CSA is a reliable marker of disease severity and can be a valuable outcome measure in long-term follow-up studies in ALD. SYNOPSIS: A prospective cohort study in 42 adrenoleukodystrophy (ALD) patients and 32 controls demonstrated that the spinal cord cross-sectional area of patients is smaller compared to healthy controls and correlates with severity of myelopathy in patients, hence it could be valuable as a much needed surrogate outcome measure.

MRI biomarkers of disease progression and conversion to secondary-progressive multiple sclerosis

INTRODUCTION

Conventional imaging measures remain a key clinical tool for the diagnosis multiple sclerosis (MS) and monitoring of patients. However, most measures used in the clinic show unsatisfactory performance in predicting disease progression and conversion to secondary progressive MS.

AREAS COVERED

Sophisticated imaging techniques have facilitated the identification of imaging biomarkers associated with disease progression, such as global and regional brain volume measures, and with conversion to secondary progressive MS, such as leptomeningeal contrast enhancement and chronic inflammation. The relevance of emerging imaging approaches partially overcoming intrinsic limitations of traditional techniques is also discussed.

EXPERT OPINION

Imaging biomarkers capable of detecting tissue damage early on in the disease, with the potential to be applied in multicenter trials and at an individual level in clinical settings, are strongly needed. Several measures have been proposed, which exploit advanced imaging acquisitions and/or incorporate sophisticated post-processing, can quantify irreversible tissue damage. The progressively wider use of high-strength field MRI and the development of more advanced imaging techniques will help capture the missing pieces of the MS puzzle. The ability to more reliably identify those at risk for disability progression will allow for earlier intervention with the aim to favorably alter the disease course.