Iron quantitative analysis of motor combined with bulbar region in M1 cortex may improve diagnosis performance in ALS

Objectives To explore whether the combined analysis of motor and bulbar region of M1 on susceptibility-weighted imaging (SWI) can be a valid biomarker for amyotrophic lateral sclerosis (ALS). Methods Thirty-two non-demented ALS patients and 35 age- and gender-matched healthy controls (HC) were retrospectively recruited. SWI and 3D-T1-MPRAGE images were obtained from all individuals using a 3.0-T MRI scan. The bilateral posterior band of M1 was manually delineated by three neuroradiologists on phase images and subdivided into the motor and bulbar regions. We compared the phase values in two groups and performed a stratification analysis (ALSFRS-R score, duration, disease progression rate, and onset). Receiver operating characteristic (ROC) curves were also constructed. Results ALS group showed significantly increased phase values in M1 and the two subregions than the HC group, on the all and elderly level (p < 0.001, respectively). On all-age level comparison, negative correlations were found between phase values of M1 and clinical score and duration (p < 0.05, respectively). Similar associations were found in the motor region (p < 0.05, respectively). On both the total (p < 0.01) and elderly (p < 0.05) levels, there were positive relationships between disease progression rate and M1 phase values. In comparing ROC curves, the entire M1 showed the best diagnostic performance. Conclusions Combining motor and bulbar analyses as an integral M1 region on SWI can improve ALS diagnosis performance, especially in the elderly. The phase value could be a valuable biomarker for ALS evaluation.

Automated summary

This study aimed to explore whether the combined analysis of motor and bulbar regions of M1 on susceptibility-weighted imaging (SWI) can serve as a valid biomarker for amyotrophic lateral sclerosis (ALS). The results showed significantly increased phase values in the M1 region and its subregions in ALS patients compared to healthy controls. The phase values were correlated with clinical scores, disease duration, and disease progression rate, and the entire M1 region showed the best diagnostic performance for ALS.