Gadolinium enhancement of the lumbar roots in a case of ALS

Cauda Equina Atrophy in Amyotrophic Lateral Sclerosis on Routine Lumbar Magnetic Resonance Imaging

OBJECTIVE

The aim of the study was to evaluate the cross-sectional area of the cauda equina in amyotrophic lateral sclerosis (ALS) on routine lumbar magnetic resonance imaging and investigate the diagnostic accuracy in comparison with age- and sex-matched non-ALS controls.

METHODS

This retrospective study included 15 ALS patients and 15 age- and sex-matched non-ALS controls. Two independent neuroradiologists measured and compared the total cross-sectional area of the cauda equina of ALS patients and the non-ALS controls at the level of the L3 and L4 using axial T2-weighted images. The cutoff value, sensitivity, specificity, and area under the curve were measured. The interobserver reproducibility of the 2 independently obtained measurements was evaluated.

RESULTS

The total cross-sectional area of the cauda equina in the ALS group was significantly smaller than that in the non-ALS group (L3: median, 66.73 vs 90.19 mm2, P < 0.001; L4: median, 52.9 vs 67.63 mm2, P < 0.001). The cutoff values at L3 and L4 were 76.95 and 61.04 mm2 with a sensitivity and specificity of 1 and 0.87 and 0.8 and 0.87, respectively. The area under the curve at L3 and L4 were high at 0.96 and 0.94, respectively. The interobserver reproducibility was 0.88 at L3 and 0.89 at L4.

CONCLUSIONS

The ALS patients showed significant atrophy of the cauda equina compared with non-ALS patients.

Breached Barriers: A Scoping Review of Blood-Central Nervous System Barrier Pathology in Amyotrophic Lateral Sclerosis

Introduction

Recent studies have implicated changes in the blood-central nervous system barriers (BCNSB) in amyotrophic lateral sclerosis (ALS). The objective of this scoping review is to synthesize the current evidence for BCNSB structure and functional abnormalities in ALS studies and propose how BCNSB pathology may impact therapeutic development.

Methods

A literature search was conducted using Ovid Medline, EMBASE, and Web of Science, from inception to November 2021 and limited to entries in English language. Simplified search strategy included the terms ALS/motor neuron disease and [BCNSB or blood-brain barrier (BBB) or blood-spinal cord barrier (BSCB)]. Henceforth, BCNSB is used as a term that is inclusive of the BBB and BSCB. Four independent reviewers conducted a title and abstract screening, hand-searched the reference lists of review papers, and performed a full text review of eligible studies. Included studies were original peer-reviewed full text publications, evaluating the structure and function of the BCNSB in preclinical models of ALS, clinical ALS, or postmortem human ALS tissue. There was no restriction on study design. The four reviewers independently extracted the data.

Results

The search retrieved 2,221 non-duplicated articles and 48 original studies were included in the synthesis. There was evidence that the integrity of the BCNSB is disrupted throughout the course of the disease in rodent models, beginning prior to symptom onset and detectable neurodegeneration. Increased permeability, pharmacoresistance with upregulated efflux transporters, and morphological changes in the supporting cells of the BCNSB, including pericytes, astrocytes, and endothelial cells were observed in animal models. BCNSB abnormalities were also demonstrated in postmortem studies of ALS patients. Therapeutic interventions targeting BCNSB dysfunction were associated with improved motor neuron survival in animal models of ALS.

Conclusion

BCNSB structural and functional abnormalities are likely implicated in ALS pathophysiology and may occur upstream to neurodegeneration. Promising therapeutic strategies targeting BCNSB dysfunction have been tested in animals and can be translated into ALS clinical trials.

Clinical and Molecular Landscape of ALS Patients with SOD1 Mutations: Novel Pathogenic Variants and Novel Phenotypes. A Single ALS Center Study

Mutations in the copper zinc superoxide dismutase 1 (SOD1) gene are the second most frequent cause of familial amyotrophic lateral sclerosis (ALS). Nearly 200 mutations of this gene have been described so far. We report all SOD1 pathogenic variants identified in patients followed in the single ALS center of Lyon, France, between 2010 and 2020. Twelve patients from 11 unrelated families are described, including two families with the not yet described H81Y and D126N mutations. Splice site mutations were detected in two families. We discuss implications concerning genetic screening of SOD1 gene in familial and sporadic ALS.

Case of Early Amyotrophic Lateral Sclerosis With Prominent Magnetic Resonance Imaging Plexus Abnormalities

Amyotrophic lateral sclerosis is a neurodegenerative disorder, which is characterized by progressive upper and lower motor neuron signs and symptoms, resulting in progressive muscle weakness. There are very rare reports of magnetic resonance imaging (MRI) abnormalities within the nerve roots or plexus reported in amyotrophic lateral sclerosis. Here, we report a patient who presented with progressive left arm weakness and was found to have bilateral MRI plexus abnormalities. This report illustrates that MRI plexus abnormalities can be seen in amyotrophic lateral sclerosis, possibly before symptoms, and may have clinical value in the diagnostic process.

MR Imaging of Brachial Plexus and Limb-Girdle Muscles in Patients with Amyotrophic Lateral Sclerosis

PURPOSE

To assess brachial plexus magnetic resonance (MR) imaging features and limb-girdle muscle abnormalities as signs of muscle denervation in patients with amyotrophic lateral sclerosis (ALS).

MATERIALS AND METHODS

This study was approved by the local ethical committees on human studies, and written informed consent was obtained from all subjects before enrollment. By using an optimized protocol of brachial plexus MR imaging, brachial plexus and limb-girdle muscle abnormalities were evaluated in 23 patients with ALS and clinical and neurophysiologically active involvement of the upper limbs and were compared with MR images in 12 age-matched healthy individuals. Nerve root and limb-girdle muscle abnormalities were visually evaluated by two experienced observers. A region of interest-based analysis was performed to measure nerve root volume and T2 signal intensity. Measures obtained at visual inspection were analyzed by using the Wald χ(2) test. Mean T2 signal intensity and volume values of the regions of interest were compared between groups by using a hierarchical linear model, accounting for the repeated measurement design.

RESULTS

The level of interrater agreement was very strong (κ = 0.77-1). T2 hyperintensity and volume alterations of C5, C6, and C7 nerve roots were observed in patients with ALS (P < .001 to .03). Increased T2 signal intensity of nerve roots was associated with faster disease progression (upper-limb Medical Research Council scale progression rate, r = 0.40; 95% confidence interval: 0.001, 0.73). Limb-girdle muscle alterations (ie, T2 signal intensity alteration, edema, atrophy) and fat infiltration also were found, in particular, in the supraspinatus muscle, showing more frequent T2 signal intensity alterations and edema (P = .01) relative to the subscapularis and infraspinatus muscles.

CONCLUSION

Increased T2 signal intensity and volume of brachial nerve roots do not exclude a diagnosis of ALS and suggest involvement of the peripheral nervous system in the ALS pathogenetic cascade. MR imaging of the peripheral nervous system and the limb-girdle muscle may be useful for monitoring the evolution of ALS and distinguishing patients with ALS from those with inflammatory neuropathy, respectively.

Magnetic resonance imaging abnormalities of peripheral nerve and muscle are common in amyotrophic lateral sclerosis and share features with multifocal motor neuropathy

INTRODUCTION

Magnetic resonance imaging (MRI) of peripheral nerve and muscle in patients with amyotrophic lateral sclerosis (ALS) may be performed to investigate alternative diagnoses, including multifocal motor neuropathy (MMN). MRI findings of peripheral nerve and muscle are not well described in these conditions, making interpretation of results difficult.

METHODS

We examined systematically the peripheral nerve and muscle MRI findings in patients with ALS (n = 60) and MMN (n = 8).

RESULTS

In patients with ALS and MMN, abnormal MRIs were common (85% and 75%, respectively), but did not correlate with disease severity. Peripheral nerve MRI abnormalities were similar in frequency (ALS 58%, MMN 63%), with most changes being of mild to moderate severity. Muscle MRI changes were more common in ALS (57% vs. 33%), and no muscle atrophy was seen in patients with MMN.

CONCLUSION

MRI abnormalities of peripheral nerve and muscle in ALS and MMN are common and share some features.