Imaging in amyotrophic lateral sclerosis: MRI and PET

Purpose of review Neuroimaging with MRI and PET has become a well-established technical tool for amyotrophic lateral sclerosis (ALS). This review summarizes current developments in the advanced neuroimaging assessment of ALS and explores their potential in a clinical and neuroscientific setting. Recent findings With a focus on diffusion-weighted imaging, MRI-based neuroimaging has shown to provide reliable measures for monitoring disease progression and should be included in the clinical workup of ALS. There have been efforts to improve the clinical utility of fluorodesoxyglucose (FDG)-PET, and multivariate analysis has made advances in discriminating patients from controls and for prognostic assessment. Beyond FDG-PET, promising investigations have been carried out implementing novel radiotracers. MRI and PET studies in ALS have consistently shown patterns of functional and structural changes considered to be the pathological signature of the disease. The constant advance of neuroimaging techniques encourages to investigate the cascade of ALS neurodegeneration and symptoms at finer and more specific level. Multicenter studies and the implementation of novel methodologies might confer a pivotal role to neuroimaging in the clinical setting in the near future, accelerating ALS diagnosis and allowing a prompt prognosis about disease progression.