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Updated: Jul 10, 2026
08:16
Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis
Published on: March 4, 2014
[Objective markers for upper motor neuron involvement in amyotrophic lateral sclerosis]
1Human Motor Control Section, Medical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Building 10, Room 5N226, 10 Center Drive, MSC 1428 Bethesda, MD 20892-1428, USA.
Brain and Nerve = Shinkei Kenkyu No Shinpo
|November 1, 2007
Summary
Objective markers for upper motor neuron (UMN) involvement in amyotrophic lateral sclerosis (ALS) are crucial for early diagnosis. Neurophysiological and advanced imaging techniques show promise in detecting UMN dysfunction, aiding disease monitoring.
Area of Science:
- Neuroscience
- Neurology
- Biomarker Discovery
Context:
- Amyotrophic lateral sclerosis (ALS) diagnosis relies heavily on clinical examination for upper motor neuron (UMN) dysfunction.
- Objective markers are needed for early diagnosis and disease progression monitoring in ALS patients.
- Current neurophysiological and imaging techniques offer potential for UMN assessment.
Purpose:
- To review and evaluate emerging neurophysiological and neuroimaging markers for detecting UMN involvement in ALS.
- To discuss the diagnostic utility and limitations of various techniques in assessing UMN pathology.
- To highlight the potential of advanced MRI techniques like MTI and DTI.
Summary:
- Transcranial magnetic stimulation (TMS) assesses UMN neurophysiological integrity, with central motor conduction time showing potential.
- Conventional MRI reveals corticospinal tract and motor cortex abnormalities, but lacks consistent sensitivity.
- Advanced MRI techniques, including Magnetization Transfer Imaging (MTI) and Diffusion Tensor Imaging (DTI), offer improved sensitivity and specificity for detecting UMN pathology in ALS.
- Proton magnetic spectroscopy shows reduced N-acetyl-aspartate, but its clinical value is uncertain.
- Diffusion Tensor Tractography (DTI) visualizes corticospinal tract integrity, correlating with UMN pathology.
Impact:
- These objective markers could significantly improve the early diagnosis and management of ALS.
- Advanced imaging and neurophysiological tools may enable more precise monitoring of disease progression.
- Further research is needed to validate these markers for routine clinical use and compare their efficacy.
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