Relationship between cervical cord 1H-magnetic resonance spectroscopy and clinoco-electromyographic profile in amyotrophic lateral sclerosis.

INTRODUCTION: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the loss of motor neurons, leading to limb paralysis and respiratory failure.
METHODS: C1-C3 cord (1) H-magnetic resonance spectroscopy ((1) H-MRS) was performed in 19 patients with ALS and 20 controls. N-acetylaspartate (NAA), choline-containing compounds, creatine plus phosphocreatine (Cr), and myo-Inositol (m-Ins) were measured. ALS functional rating scale-revised (ALSFRS) and forced vital capacity (FVC) were assessed. The rates of decline were calculated at 6 months before and after (1) H-MRS.
RESULTS: NAA/Cr and NAA/m-Ins were decreased significantly, and m-Ins/Cr was increased significantly in ALS patients compared with controls. NAA/Cr and NAA/m-Ins were correlated with ALSFRS and FVC and inversely linked to the decline rates. NAA/Cr, NAA/m-Ins, and m-Ins/Cr were altered markedly in 9 patients with denervation and neurogenic changes in both C2 paraspinal and upper limb muscles.
CONCLUSIONS: These metabolite ratios were associated with disease progression and ongoing denervation in neck and hand muscles. C1-C3 cord (1) H-MRS might reflect anterior horn cell damage causing neck/arm weakness and respiratory dysfunction in ALS patients.