A longitudinal diffusion tensor MRI study of the cervical cord and brain in amyotrophic lateral sclerosis patients

ArticleinJournal of neurology, neurosurgery, and psychiatry 80(1):53-5 · November 2008with16 Reads
DOI: 10.1136/jnnp.2008.154252 · Source: PubMed
  • 45.67 · San Raffaele Scientific Institute
  • 49.97 · Ospedale di San Raffaele Istituto di Ricovero e Cura a Carattere Scientifico
  • 41.66 · Ospedale di San Raffaele Istituto di Ricovero e Cura a Carattere Scientifico
Abstract
To define the temporal evolution of intrinsic tissue damage and atrophy in the cervical cord and the brain portion of the corticospinal tracts (CST) from patients with amyotrophic lateral sclerosis (ALS). Conventional and diffusion tensor (DT) magnetic resonance imaging (MRI) of the cervical cord and brain were obtained from 17 ALS patients and 20 controls, at baseline and after a mean follow-up of 9 months. The following measurements were assessed: (a) cervical cord cross-sectional area, average mean diffusivity (MD) and average fractional anisotropy (FA); and (b) CST T2-visible hyperintensities, average MD and FA. During the follow-up, ALS patients showed a significant decrease in cord area (p = 0.003) and cord average FA (p = 0.01), and a significant increase in cord average MD (p = 0.01). In ALS patients, longitudinal changes of diffusivity measurements were not associated with cord area changes. At baseline, brain CST average MD was significantly higher in ALS patients compared with controls (p = 0.001). Brain CST diffusivity measurements remained stable over time in ALS patients and did not correlate with cord damage. This study shows that progressive tissue loss and injury to the remaining tissue occur in the cervical cord of ALS patients and that these two features of ALS-related pathology are not strictly interrelated. Cord pathology in ALS patients is likely to be independent of brain changes, indicating that imaging the cervical cord may be a useful adjunctive tool to monitor ALS evolution.
    • "Pooled sensitivity and specificity for DTI in the assessment of changes observed in MND patients was found to be 68% and 73% respectively (Foerster et al., 2013a). The spreading of FA reduction into frontal regions and the cerebellum (Keil et al., 2012 ) in longitudinal studies also correlated with ALSFRS-R, disease duration and disease progression (Jacob et al., 2003; Agosta et al., 2009; Zhang et al., 2011; Keil et al., 2012). In addition, FA was also found to be reduced in the corpus callosum of patients with MND/ALS and particular, the middle posterior body of the corpus that connects the motor and motor association cortices thus supporting the hypothesis that disease propagates along structural connections (Sach et al., 2004; Filippini et al., 2010; Bak and Chandran, 2012; Foerster et al., 2013b; Chapman et al., 2014) (Fig. 8). "
    [Show abstract] [Hide abstract] ABSTRACT: Clinical signs of upper motor neuron (UMN) involvement are an important component in supporting the diagnosis of amyotrophic lateral sclerosis (ALS), but are often not easily appreciated in a limb that is concurrently affected by muscle wasting and lower motor neuron degeneration, particularly in the early symptomatic stages of ALS. Whilst recent criteria have been proposed to facilitate improved detection of lower motor neuron impairment through electrophysiological features that have improved diagnostic sensitivity, assessment of upper motor neuron involvement remains essentially clinical. As a result, there is often a significant diagnostic delay that in turn may impact institution of disease-modifying therapy and access to other optimal patient management. Biomarkers of pathological UMN involvement are also required to ensure patients with suspected ALS have timely access to appropriate therapeutic trials. The present review provides an analysis of current and recently developed assessment techniques, including novel imaging and electrophysiological approaches used to study corticomotoneuronal pathology in ALS.
    Full-text · Article · May 2016
    • "Particularly, FA values correlated with disability, and focal atrophy of the spinal cord correlated with muscle deficits [104, 105] . Longitudinal reductions in cord FA and elevation in cord MD have been shown in ALS patients after a mean follow-up of 9 months [106] . Reduced NAA:Cr and NAA:myo-inositol ratios have been reported in the cervical cord in ALS patients [107, 108] and in presymptomatic carriers of SOD1 mutations [109], raising the potential for screening and early detection. "
    [Show abstract] [Hide abstract] ABSTRACT: Modern technology has improved the ability to probe effectively the underlying biology of ALS by examination of genomic, proteomic and physiological changes in patients with ALS, as well as to monitor functional and structural changes during the course of disease. While effective treatments for ALS are lacking, the discovery of sensitive biomarkers to disease activity offers clinicians tools for rapid diagnosis and insights into the pathophysiology of ALS. The ultimate aim is to lessen reliance on clinical measures and survival as trial endpoints and broaden the therapeutic options for patients with this disease.
    Full-text · Article · Dec 2015
    • "Hitherto, research aimed at developing visual ALS biomarkers has focused mainly on brain testing and has neglected the significance of the spinal cord [4, 8], although the role of spinal cord lesion in the course of this disease has been confirmed in anatomo-pathological examinations. Additionally, imaging of the spinal cord is technically difficult [3], and the literature regarding the meaning of diagnostic imaging of the spinal cord in ALS is relatively scarce [6, 7, 12]. Nair et al. [3] indicated the significant role of spinal cord DTI in ALS diagnostics. "
    [Show abstract] [Hide abstract] ABSTRACT: Diagnosis of amyotrophic lateral sclerosis (ALS) is based on clinical criteria and electrophysiological tests (electromyography, and transcranial magnetic stimulation). In the search for ALS biomarkers, the role of imaging procedures is currently emphasized, especially modern MR techniques. MR procedures were performed on 15 ALS patients and a sex- and age-matched control group. The MR examinations were performed with a 1.5-T MR unit, and the protocol consisted of sagittal T1-weighed images, sagittal and axial T2-weighed images, and sagittal T2-weighed FAT SAT images followed by an axial diffusion tensor imaging (DTI) sequence of the cervical spinal cord. FA values in individual segments of the cervical spinal cord were decreased in the ALS group in comparison with the control group. After comparing FA values for anterior, posterior, and lateral corticospinal columns, the greatest difference was observed between the C2 and C5 segments. Spinal cord assessment with the use of FA measurements allows for confirmation of the motor pathways lesion in ALS patients. The method, together with clinical criteria, could be helpful in ALS diagnosis, assessment of clinical course, or even the effects of new drugs. The results also confirmed the theory of the generalized character of ALS.
    Article · Nov 2015
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