Diffusion tensor imaging in early amyotrophic lateral sclerosis using 3T magnetic resonance imaging

Objective: Amyotrophic lateral sclerosis (ALS) is a multisystem condition which impairs white matter, corticospinal tract and frontotemporal functions including cognition and behavior. This study aimed to perform diffusion tensor imaging (DTI) to detect white matter microstructural abnormalities, and also understanding the pathophysiology in ALS using 3T magnetic resonance imaging. Methods: The study examined 12 patients (7 males, 5 females) with sporadic ALS and 10 subjects in the control group (7 males, 3 females) by voxel-based analysis of DTI with 3T MRI. We compared fractional anisotropy (FA) and apparent diffusion coefficient (ADC) parameters in the corticospinal tracts among patients who had ALS and those in the healthy control by DTI region of interest (ROI) and tractography techniques. Results: The FA and ADC measurements of the patient group were respectively 0.638 +/- 0.041 and 0.350 +/- 0.01 (p<0.001). The results of the healthy control group were respectively 0.701 +/- 0.054 and 0.288 +/- 0.027 (p<0.05). DTI showed decreased fractional anisotropy in bilateral corticospinal tracts and internal capsule posterior crus. There was a correlation between the FA reductions in this region and the severity of the disease in the patients with ALS. Conclusion: Consequently, with this longitudinal DTI study, the progress of upper motor fiber degeneration in ALS was demonstrated. It may be useful to utilize DTI to monitor the progress and effectiveness of treatment interventions, as well as understanding the pathophysiology of ALS.