Keywords: Spinal Cord, Spinal Cord, Morphometric Measures; Normalization; Normative Values

Motivation: Spinal cord morphometric measures are commonly used to evaluate spinal cord pathologies. Yet, their interpretation is challenged by considerable intra- and inter-subject variability.

Goal(s): Develop a method for automatic normalization relative to a healthy cohort to reduce inter-subject variability.

Approach: Morphometric measures computed from an open-access dataset (N=203) were linearly interpolated using a newly proposed approach into the spinal cord template to build a normative database.

Results: The methodology is open-source and allows normalization based on sex, MRI vendors, and age decades, thereby minimizing inter-subject variability associated with demographic and biological factors.

Impact: This new morphometric database will allow researchers to normalize based on sex, MRI vendors, and age decades, thereby minimizing inter-subject variability associated with demographic and biological factors. The method is open-source and available in Spinal Cord Toolbox.

Keywords: Spinal Cord, Quantitative Imaging, Spinal cord, T1map, Segmentation, Template, 7T

Motivation: Right-left differences in MR metrics can help identify pathological or specific regions of abnormalities. However, this requires investigating them first on a healthy population

Goal(s): To Investigate whether right-left spinal cord (SC) asymmetry can be identified in vivo and, if yes, determine in which specific  regions

Approach: Right-left SC asymmetry was investigated based on cross-sectional area measurements and T1mapping derived from high-resolution 7T MRI and  atlas-based segmentation with the AMU7T quantitative template

Results: Right-left T1 asymmetry in the cervical cord was evidenced in one-third of the AMU7T parcels, mostly in motor tracts, but not in lateral corticospinal tracts

Impact: High-resolution quantitative 7T MR imaging and dedicated template may help identify microstructural asymmetry in the spinal cord. Such findings may have to be considered in the future when investigating pathological cohorts

Keywords: Spinal Cord, Spinal Cord

Motivation: Previous perfusion-weighted imaging studies in multiple sclerosis (MS) have revealed alterations of cerebral perfusion, yet these types of studies have not been translated to studying MS in the spinal cord.

Goal(s): Evaluate the use of intravoxel incoherent motion (IVIM) as a non-contrast MRI technique to assess perfusion in the spinal cord of MS.  

Approach: A cross-sectional analysis was conducted to determine spinal cord, white matter, and gray matter differences in IVIM-derived indices between the healthy and MS cohorts.

Results: Spinal cord white matter perfusion fraction (p=0.082) and pseudo-diffusion (p=0.055) measurements came close to statistical significance between MS patients and healthy controls.  

Impact: This is the first study utilizing IVIM in the spinal cord and the findings suggest that IVIM has potential as a tool for assessing the microcirculation of the human spinal cord in MS. 

Keywords: Spinal Cord, Spinal Cord, CEST, qMT

Motivation: To evaluate quantitative MRI metrics as biomarkers of spinal cord injury treatment effects in a rat contusion model.

Goal(s): Determine the efficacy of Riluzole on SCI inflammation and myelination and quantify concomitant changes in MRI parameters longitudinally in treated and control animals.

Approach: We acquired CEST and qMT MR images in anesthetized rats after a lumbar contusion injury, and quantified longitudinal changes associated with neuroinflammation and demyelination for 8 weeks in Riluzole treatment and controls animals.

Results: Increase in CEST (3.5 ppm) APT concentration and PSR values were correlated with Riluzole effect, indicating their utility as biomarkers for treatment response.

Impact: The use of quantitative MRI imaging can be used to non-invasively probe SCI treatment efficacy in pre-clinical studies. This will improve and further the development of novel SCI treatments.

Keywords: Spinal Cord, Spinal Cord

Motivation: Traumatic spinal cord injury (SCI) leads to a perfusion deficit in the cervical cord, a factor that significantly contributes to neurodegeneration. Characterizing changes in perfusion after injury holds potential to better understand progressive SCI-induced neurodegeneration.

Goal(s): To determine blood perfusion changes in the cervical cord of tetraplegic SCI patients using intravoxel incoherent motion (IVIM) MRI.

Approach: Cardiac-gated IVIM MRI was applied to the cervical cord in 21 SCI patients and 38 healthy controls (HC). 

Results: SCI patients showed significant changes in IVIM parameters in the grey matter of the cervical cord compared to HC, indicating remote perfusion deficit above the injury site.

Impact: The characterization of spinal cord perfusion changes in SCI provides valuable insights into tissue-specific changes which can serve as a foundation for the development of targeted treatment strategies.

Keywords: Spinal Cord, Motion Correction, MR Value, Body, Clinical Applications, Spine

Motivation: Patient motion during spine MRI significantly degrades diagnostic utility.

Goal(s): Demonstrate the benefits of an efficient retrospective motion correction technique across clinical 2D TSE spine protocols.

Approach: A rapid low-resolution scout scan in combination with a small number of additional calibration lines are utilized for on-the-fly bulk motion estimation. Region-targeting coil-combination methods are used to model non-rigid motion in the spine. Generalized reconstructions are performed using locally rigid motion information.

Results: Improved image quality for in vivo L- and C-spine scans utilizing partially non-rigid motion correction for instructed subject motion experiments.

Impact: A strategy for performing motion estimation and correction in TSE spine imaging is proposed. Region-targeting coil-combination methods allow for isolation of different spatial sources of non-rigid motion. Improved image quality is demonstrated in vivo under supervised motion conditions.

Keywords: Spinal Cord, Neuro, cervical spondylotic myelopathy

Motivation: MUSE-DTI may elevate spatial resolution and image quality in cervical spine.

Goal(s): This study aimed to investigate the clinical diagnosis value of MUSE-DTI in patients with cervical spondylotic myelopathy (CSM).

Approach: Independent T-test or Mann-Whitney t test and Spearman correlation analysis was used to investigate the differences of FA and ADC values between each two different stages and the correlation to JOA scores.

Results: All MUSE-DTI derived values at MCL were correlated with the clinical JOA scores. The axial diffusivity (AD) values were most sensitive to the secondary damage of distal spinal cord.

Impact: This study presented the ability of MUSE-DTI in better display cervical spinal cord and spinal cord injury with more reliable measurements for the clinical diagnosis and treatment of CSM patients.

Keywords: Spinal Cord, Velocity & Flow, CSF

Motivation: Understanding the fluid mechanics of the cerebrospinal (CSF) flow is important for creating more accurate models of flow dynamics in intrathecal drug delivery systems.

Goal(s): We assess the feasibility of measuring with high-temporal resolution 3-directional CSF flow across all sections of the spine in healthy volunteers.

Approach: We report peak-to-peak velocity, peak velocity, flow rate, total displacement, and display velocity vector fields for the CSF across the three spinal sections. 

Results: 3-directional CSF flow of the full spine can be measured with MRI. Our observations revealed varying CSF velocity profiles across three sections of the spine, indicating distinct pressure mechanisms along its length.

Impact: Recent research have focused on the development of novel therapeutic strategies for CNS drug delivery though intrathecal space modelling. To achieve this and establish better boundary conditions, more precise measurements of spinal CSF flow through MRI are required.

Keywords: Peripheral Nerves, Nervous system

Motivation:  Guillain-Barré syndrome (GBS) has an unpredictable outcome, and it's vital to find ways to forecast its progression, as some patients may face severe disability or even death.

Goal(s): The study aimed to assess the value of MRI grading scores for muscle denervation edema in predicting the course of GBS.

Approach: We conducted a retrospective analysis on 354 GBS patients, employing a 5-point MRI grading scale. We compared the predictive capabilities of models using only clinical data against those that combined clinical information with MRI findings.

Results: The results clearly demonstrated that including MRI data significantly enhanced the accuracy of predictions for patient outcomes.

Impact: MRI grading scores may improve GBS prognosis, enable personalized treatment, and potentially reduce morbidity. This method paves the way for incorporating imaging biomarkers in neurological disorders to improve clinical strategies.

Keywords: Spinal Cord, Spinal Cord

Motivation: To correct breathing-induced field fluctuations and ensuing artifacts on T2*-weighted MRI of the cervical cord to improve T2* mapping. 

Goal(s): To characterize B₀ field changes caused by respiration within the cervical cord and to retrospectively compensate for those spatiotemporal fluctuations using a FID navigator-based correction technique.

Approach: B₀ field coefficients up to second order were measured using FID navigators and a multi-channel low-resolution reference image. Retrospective correction was performed using measured field coefficients during an iterative image reconstruction. 

Results: The FIDnav framework characterized the B₀ field changes and improved the quality of T2*-weighted MRI and T2* maps by correcting respiratory-induced artifacts. 

Impact: Improved quality of T2*-weighted images, obtained after correction of respiration-induced field changes, holds promise for improving MRI techniques relying on T2* contrast (BOLD fMRI, QSM) and clinical applications in neurological diseases of the cervical cord. 

Keywords: Spinal Cord, High-Field MRI, UHF 7T, Spinal Cord, qMRI, reproducibility

Motivation: Conducting multi-center 7T quantitative MRI studies on the spinal cord requires acquisition protocols with high reliability.

Goal(s): To provide a consensus cervical cord qMRI protocol with high reliability by means of  determining its repeatability and reproducibility across a dual center test-retest study.

Approach: Six healthy controls underwent a multiparametric protocol back-to-back 3 times with a break, which include T1-MP2RAGE and T2*-weighted on two 7T scanners. 

Results: T1 values and spinal cord area (on C1-C5 level) show high repeatability (CoV<2%; Cov <1.2% respectively and high reproducibility (Cov<2.6%; <9.9% respectively) within and between subjects.

Impact: This work represents an important step towards the adoption of UHF MRI protocol for various neurological pathologies affecting the spinal cord. It empowers neurologists and scientists investigating neurodegenerative diseases with high reliability and robustness. 

Keywords: Spinal Cord, Spinal Cord, Optical nerve

Motivation: We intend to employ advanced imaging methods to explain pathologic clinical scenarios involving the spine and optical nerve sheath. Motion in these applications is driven by cardiac pulsatility, and the pulsatile motion occurs across CSF-tissue boundary.

Goal(s): In this work, we tested if cardiac-gated cine MR imaging combined with video amplification can visualize sub-voxel motion.

Approach: Pulsatile motion profiles were extracted and quantitatively compared.

Results: Pulsatile motion in healthy and pathological use cases are compared. 

Impact: Amplified MRI (aMRI) is a visualization method that shows pulsatile dynamics and is used to study brain pulsation. We have shown additional use-cases in spinal cord motion and optical nerve sheath dynamics.

Keywords: Spinal Cord, Magnetization transfer

Motivation: Quantitative spinal cord imaging is essentially helpful in various pathological conditions, such as degenerative cervical myelopathy (DCM).  However, the role of myelin-sensitive techniques in DCM seems to be underestimated. 

Goal(s): Assess demyelination within different spinal tracts in patients with DCM.

Approach: Spinal cord 3T MRI with magnetization transfer ratio (MTR) technique was performed with subsequent post-processing in Spinal Cord Toolbox (v5.5). 

Results: We revealed structural impairment of the spinocerebellar, rubrospinal, and reticulospinal tracts, as well as fasciculus cuneatus, in patients with DCM compared to the control group. The associations between JOA score and MTR values within spinal cord white matter were also found.

Impact: Our results could help to better understand the pathophysiology of DCM.  Further studies in this field could be dedicated toassociations of MTR values with surgical recovery, links with supraspinal structural changes, or comparisons with other quantitative techniques.

Keywords: Spinal Cord, Spinal Cord, Clinical Trial

Motivation:  Assessing the extent of intramedullary lesion after traumatic spinal cord injury (tSCI) has been shown to correlate with the severity of tSCI. We expand this approach, by understanding the injury's impact on individual spinal tracts and evaluating its connection to clinical severity.

Goal(s): To fully characterize the extent of injury to the ascending and descending tracts on T2-weighted sagittal scans.

Approach: We achieve this by manually delineating the lesion based on T2w-sagittal scans, projecting it into three planes, enabling 3D-visualization.

Results: Significant correlations between damage to the left- and right-descending tracts, right-ascending tract and tract-associated clinical scores were found, indicating clinical validity.

Impact: 3D-lesion characterization allows tract-specific analysis in traumatic SCI patients. It allows a precise assessment of injury to specific tracts on both sides of the spinal cord. This approach can inform tailored treatment and rehabilitation strategies.

Keywords: Spinal Cord, Spinal Cord

Motivation: Determining the clinical significance of spinal cord changes across various neurological diseases.

Goal(s): Determining the clinical significance of spinal cord changes across various neurological diseases.

Approach: We compared the spinal cord changes across various neurological diseases, followed by analyzing the correlation of spinal cord atrophy with regional brain atrophy and corresponding clinical variables.

Results: The spinal cord atrophy happens with aging and is aggravated in neurological diseases, which partly reflects cognitive conditions and physical disability. 

Impact:  Identifying disease-specific patterns of spinal cord atrophy somehow helps in differential diagnosis and MUCCA could be serve as a MRI marker for cognitive impairment and/or physical disability.

Keywords: Spinal Cord, Neuro, Myelin

Motivation: Discrimination between gray and white matter of the spinal cord remains challenging. 

Goal(s): To investigate imaging techniques that best discriminate gray matter from white matter.

Approach: Inhomogeneous magnetization transfer (ihMT) and phase-sensitive inversion recovery (PSIR) have been reported effective in discriminating between gray and white matter. Myelin-sensitive inversion recovery (MySIR) was compared with ihMT and PSIR for evaluating the discriminability between gray and white matter.

Results: MySIR had the highest contrast ratio compared to ihMT and PSIR.

Impact: MySIR was superior to ihMT and PSIR in discriminating gray matter from white matter, and MySIR can be useful as a new myelin-specific MR imaging technique for spinal cord segmentation.