Longitudinal changes of spinal cord grey and white matter following spinal cord injury

Abstract

ObjectivesTraumatic and non-traumatic spinal cord injury produce neurodegeneration across the entire neuraxis. However, the spatiotemporal dynamics of spinal cord grey and white matter neurodegeneration above and below the injury is understudied.MethodsWe acquired longitudinal data from 13 traumatic and 3 non-traumatic spinal cord injury patients (8–8 cervical and thoracic cord injuries) within 1.5 years after injury and 10 healthy controls over the same period. The protocol encompassed structural and diffusion-weighted MRI rostral (C2/C3) and caudal (lumbar enlargement) to the injury level to track tissue-specific neurodegeneration. Regression models assessed group differences in the temporal evolution of tissue-specific changes and associations with clinical outcomes.ResultsAt 2 months post-injury, white matter area was decreased by 8.5% and grey matter by 15.9% in the lumbar enlargement, while at C2/C3 only white matter was decreased (−9.7%). Patients had decreased cervical fractional anisotropy (FA: −11.3%) and increased radial diffusivity (+20.5%) in the dorsal column, while FA was lower in the lateral (−10.3%) and ventral columns (−9.7%) of the lumbar enlargement. White matter decreased by 0.34% and 0.35% per month at C2/C3 and lumbar enlargement, respectively, and grey matter decreased at C2/C3 by 0.70% per month.ConclusionsThis study describes the spatiotemporal dynamics of tissue-specific spinal cord neurodegeneration above and below a spinal cord injury. While above the injury, grey matter atrophy lagged initially behind white matter neurodegeneration, in the lumbar enlargement these processes progressed in parallel. Tracking trajectories of tissue-specific neurodegeneration provides valuable assessment tools for monitoring recovery and treatment effects.

Cellular and Molecular Gradients in the Ventral Horns With Increasing Distance From the Injury Site After Spinal Cord Contusion

“…A clinical neurophysiological and MRI studies indicated the development of these events in distant areas of patients’ spinal cord after spinal cord injury. Distinct spatiotemporal dynamics of tissue-specific neurodegeneration were found above and below spinal cord injury ( David et al, 2021 ). Spatiotemporal experimental analysis of the gray and white matter of the spinal cord at a distance from the epicenter of injury shows the differential pattern and severity of pathological reactions, gene expression, and molecular regulation in the remote rostral and caudal regions ( Ek et al, 2010 ; Yu et al, 2019 ).…”

Dynamics of progressive degeneration of major spinal pathways following spinal cord injury: A longitudinal study

“…After SCI, the primary injury triggers a cascade of pathophysiological processes at the focal injury site ( Ahuja et al, 2017 ) with subsequent secondary disease processes (i.e. anterograde, retrograde, and trans-synaptic degeneration) ( David et al, 2021 , David et al, 2019 , David et al, 2022 , Freund et al, 2019 , Freund et al, 2013b , Grabher et al, 2015 , Lundell et al, 2011 , Seif et al, 2018a , Seif et al, 2020 , Ziegler et al, 2018 ). Histopathological evidence illustrates that at the earliest stage post-SCI axonal swelling and myelin thinning can be detected at the lesion border ( Brennan et al, 2013 , Bresnahan, 1978 , Bresnahan et al, 1976 , Buss et al, 2005 , Grumbles and Thomas, 2017 ).…”

In Vivo and 3D Imaging Technique(s) for Spatiotemporal Mapping of Pathological Events in Experimental Model(s) of Spinal Cord Injury

“…SCI causes local damage to the tissue and leads to the secondary pathological cascade, such as spatiotemporal changes in gray and white matter atrophy . Studies reported longitudinal changes in gray and white matter composition after the spinal cord injury . The white matter contains the axonal trajectories, which can be misinterpreted as the regenerated fibers while present as the spared axons.…”