PET Imaging in ALS

Abstract

Amyotrophic lateral sclerosis is a neurodegenerative disorder that primarily affects the motor system, but extramotor involvement is common. Progressive muscle weakness and wasting, including bulbar and respiratory muscles, limit survival to 2–5 years after disease onset in most patients. The diagnosis is made on clinical grounds and is based on the presence of signs of upper and lower motor neuron loss in different body regions in the absence of other pathologies that can explain the symptoms and signs of the patient. Making an accurate diagnosis can be difficult in early disease stages. ALS is a heterogeneous disorder with variability in age at onset, in phenotypic presentation, in the extent of frontotemporal involvement and in the disease progression rate. There is a high unmet medical need for objective markers that aid in early diagnosis and in predicting disease outcome. In this chapter, the current knowledge about the diagnostic and prognostic value of 18F 2-fluoro-2-deoxy-D-glucose-PET in ALS is discussed. The potential of other targets and PET tracers to visualize different aspects of ALS disease pathology is described.