Quantitative neuroimaging biomarkers in a series of 20 adult patients with POLG mutations.

Mutations in the gene encoding polymerase gamma (POLG) are a common cause of mitochondrial diseases in adults. We retrospectively analyzed volumetric and diffusion tensor imaging data from 20 adult POLG-mutated patients compared to healthy controls. We used an original clinical binary load score and electroneuromyography to evaluate disease severity. Patients showed atrophy in the basal ganglia, amygdala, and brainstem (p < 0.05) compared to controls, as well as decreased fractional anisotropy (FA) in the cingulate gyrus, the internal capsule and the corona radiata (p < 0.05). Clinical scores correlated with decreased FA and increased radial diffusivity in several brain regions (p < 0.05).