Amide signal intensities may be reduced in the motor cortex and the corticospinal tract of ALS patients

• Published in: European radiology Vol. 31; no. 3; pp. 1401 - 1409
• Main Authors: Dai, Zhuozhi, Kalra, Sanjay, Mah, Dennell, Seres, Peter, Sun, Hongfu, Wu, Renhua, Wilman, Alan H.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.03.2021; Springer Nature B.V
• Subjects: Abnormalities; Amides; Amyotrophic lateral sclerosis; Amyotrophic Lateral Sclerosis - diagnostic imaging; Canada; Consortia; Correlation analysis; Cortex (motor); Diagnostic Radiology; Diagnostic systems; Diffusion; Humans; Imaging; Internal Medicine; Interventional Radiology; Magnetic Resonance; Magnetic Resonance Imaging; Medical imaging; Medicine; Medicine & Public Health; Motor Cortex - diagnostic imaging; Neurodegenerative Diseases; Neuroimaging; Neuroradiology; Protons; Pyramidal tracts; Pyramidal Tracts - diagnostic imaging; Radiology; Resonance; Substantia grisea; Ultrasound; Canada; Magnetic resonance imaging; Brain; Amyotrophic lateral sclerosis
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s00330-020-07243-4

Objectives The aim of the study is to assess amide concentration changes in ALS patients compared with healthy controls by using quantitative amide proton transfer (APT) and multiparameter magnetic resonance imaging, and testing its correlation with clinical scores. Methods Sixteen ALS patients and sixteen healthy controls were recruited as part of the Canadian ALS Neuroimaging Consortium, and multimodal magnetic resonance imaging was performed at 3 T, including APT and diffusion imaging. Lorentz fitting was used to quantify the amide effect. Clinical disability was evaluated using the revised ALS functional rating scale (ALSFRS-R), and its correlation with image characteristics was assessed. The diagnostic performance of different imaging parameters was evaluated with receiver operating characteristic analysis. Results Our results showed that the amide peak was significantly different between the motor cortex and other gray matter territories within the brain of ALS patients ( p  < 0.001). Compared with controls, amide signal intensities in ALS were significantly reduced in the motor cortex ( p  < 0.001) and corticospinal tract ( p  = 0.046), while abnormalities were not detected using routine imaging methods. There was no significant correlation between amide and ALSFRS-R score. The diagnostic accuracy of the amide peak was superior to that of diffusion imaging. Conclusions This study demonstrated changes of amide signal intensities in the motor cortex and corticospinal tract of ALS patients. Key Points • The neurodegenerative disease amyotrophic lateral sclerosis (ALS) has a lack of objective imaging indicators for diagnosis and assessment. • Analysis of amide proton transfer imaging revealed changes in the motor cortex and corticospinal tract of ALS patients that were not visible on standard magnetic resonance imaging. • The diagnostic accuracy of the amide peak was superior to that of diffusion imaging.