Fractional Anisotropy in the Posterior Limb of the Internal Capsule and Prognosis in Amyotrophic Lateral Sclerosis

Abstract

To explore the value of diffusion tensor imaging applied to those specific cerebral white matter tracts consistently involved pathologically in amyotrophic lateral sclerosis as a source of prognostic biomarkers.Design: Baseline clinical assessment and 3-T diffusion tensor imaging, repeated after approximately 6 months. Tract-based spatial statistics were used to assess voxelwise correlations of just the baseline diffusion tensor imaging indices with the progression rate (change in disability score/time interval) within the corticospinal tract and corpus callosum. Patients:The study involved 21 patients with amyotrophic lateral sclerosis and 3 patients with primary lateral sclerosis.Results: Correlation was observed between fractional anisotropy and progression rate for a region of the corticospinal tract spanning the posterior limb of the internal capsule, with a left hemisphere emphasis. Posterior limb of the internal capsule fractional anisotropy showed potential to distinguish those patients with rapid progression. Axial diffusivity significantly increased in this region in a paired t test analysis of baseline and follow-up diffusion tensor imaging, in keeping with axonal damage. No correlations were noted for the corpus callosum.Conclusions: Posterior limb of the internal capsule fractional anisotropy is a candidate prognostic marker in amyotrophic lateral sclerosis, with potential to identify incident cases with more rapid progression.

Diffusion tensor MRI of the corpus callosum in amyotrophic lateral sclerosis

“…This idea conflicts with postmortem reports indicating that alterations in motor neuron cell bodies and axonal processes are at least as prominent as observations of demyelination . However, our observation of increased AD, also recently seen in ALS , could be indicative of axonal loss. Future advances in the understanding of the histologic correlates of different DTI metrics would serve well to inform this discussion.…”

Diffusion tensor MRI of the corpus callosum in amyotrophic lateral sclerosis

“…This idea conflicts with postmortem reports indicating that alterations in motor neuron cell bodies and axonal processes are at least as prominent as observations of demyelination . However, our observation of increased AD, also recently seen in ALS , could be indicative of axonal loss. Future advances in the understanding of the histologic correlates of different DTI metrics would serve well to inform this discussion.…”

Widespread grey matter pathology dominates the longitudinal cerebral MRI and clinical landscape of amyotrophic lateral sclerosis

“…We observed some regional grey and white matter changes in relation to clinical features, and in exploratory region of interest analysis confirmed our previous observations of correlation of fractional anisotropy within the corticospinal tract in relation to rate of progression (Menke et al , 2012). However the goal of translating MRI-based metrics for the stratification of patients with ALS, for example in the context of a clinical trial, does not seem likely at present in comparison with more easily acquired examination-based information.…”

Structural Connectivity Alterations in Amyotrophic Lateral Sclerosis: A Graph Theory Based Imaging Study

“…Our results are in line with the reports of decreased of Eglob in previous studies (Zhang et al, 2019). Our findings also support the notion of widespread, multisystem, multi-network degeneration in ALS which has been conceived based on other structural (Keil et al, 2012; Menke et al, 2012; Bede et al, 2016; Müller et al, 2016) and functional methods (Agosta et al, 2011; Douaud et al, 2011; Geevasinga et al, 2017; Dukic et al, 2019; Nasseroleslami et al, 2019). Reduced global connectivity underpins the impaired integration of multiple cerebral circuits in ALS, which may be driven by long-range connectivity changes (He et al, 2009).…”

Diffusion tensor MRI of the corpus callosum in amyotrophic lateral sclerosis

“…This idea conflicts with postmortem reports indicating that alterations in motor neuron cell bodies and axonal processes are at least as prominent as observations of demyelination . However, our observation of increased AD, also recently seen in ALS , could be indicative of axonal loss. Future advances in the understanding of the histologic correlates of different DTI metrics would serve well to inform this discussion.…”

Widespread grey matter pathology dominates the longitudinal cerebral MRI and clinical landscape of amyotrophic lateral sclerosis

“…We observed some regional grey and white matter changes in relation to clinical features, and in exploratory region of interest analysis confirmed our previous observations of correlation of fractional anisotropy within the corticospinal tract in relation to rate of progression (Menke et al , 2012). However the goal of translating MRI-based metrics for the stratification of patients with ALS, for example in the context of a clinical trial, does not seem likely at present in comparison with more easily acquired examination-based information.…”

Structural Connectivity Alterations in Amyotrophic Lateral Sclerosis: A Graph Theory Based Imaging Study

“…Our results are in line with the reports of decreased of Eglob in previous studies (Zhang et al, 2019). Our findings also support the notion of widespread, multisystem, multi-network degeneration in ALS which has been conceived based on other structural (Keil et al, 2012; Menke et al, 2012; Bede et al, 2016; Müller et al, 2016) and functional methods (Agosta et al, 2011; Douaud et al, 2011; Geevasinga et al, 2017; Dukic et al, 2019; Nasseroleslami et al, 2019). Reduced global connectivity underpins the impaired integration of multiple cerebral circuits in ALS, which may be driven by long-range connectivity changes (He et al, 2009).…”

Diffusion tensor MRI of the corpus callosum in amyotrophic lateral sclerosis

“…This idea conflicts with postmortem reports indicating that alterations in motor neuron cell bodies and axonal processes are at least as prominent as observations of demyelination . However, our observation of increased AD, also recently seen in ALS , could be indicative of axonal loss. Future advances in the understanding of the histologic correlates of different DTI metrics would serve well to inform this discussion.…”

Widespread grey matter pathology dominates the longitudinal cerebral MRI and clinical landscape of amyotrophic lateral sclerosis

“…We observed some regional grey and white matter changes in relation to clinical features, and in exploratory region of interest analysis confirmed our previous observations of correlation of fractional anisotropy within the corticospinal tract in relation to rate of progression (Menke et al , 2012). However the goal of translating MRI-based metrics for the stratification of patients with ALS, for example in the context of a clinical trial, does not seem likely at present in comparison with more easily acquired examination-based information.…”

Structural Connectivity Alterations in Amyotrophic Lateral Sclerosis: A Graph Theory Based Imaging Study

“…Our results are in line with the reports of decreased of Eglob in previous studies (Zhang et al, 2019). Our findings also support the notion of widespread, multisystem, multi-network degeneration in ALS which has been conceived based on other structural (Keil et al, 2012; Menke et al, 2012; Bede et al, 2016; Müller et al, 2016) and functional methods (Agosta et al, 2011; Douaud et al, 2011; Geevasinga et al, 2017; Dukic et al, 2019; Nasseroleslami et al, 2019). Reduced global connectivity underpins the impaired integration of multiple cerebral circuits in ALS, which may be driven by long-range connectivity changes (He et al, 2009).…”