The cerebellar bioenergetic state predicts treatment response in COQ8A-related ataxia

Introduction: Primary coenzyme Q10 (CoQ10) deficiency, a recessive disorder associated with various defects of CoQ10 biosynthesis and widely varying clinical presentation, is customarily managed by oral Q10 supplementation but the benefit is debated. Methods: To address this question, we mapped individual responses in two patients with COQ8A-related ataxia following coenzyme Q10 supplementation using noninvasive imaging. Metabolic ³¹phosphorus magnetic resonance spectroscopy imaging (³¹P-MRSI) and volumetric cerebellar neuroimaging were performed to quantify the individual treatment response in two patients with COQ8A-related ataxia, each compared with eight age- and gender-matched healthy control subjects. Results: Post-treatment change in energy metabolite levels differed in the two patients, with higher energy levels and improved dysarthria and leg coordination in one, and decreased energy levels without clinical benefit in the other. Conclusions: Our results suggest that the cerebellar bioenergetic state may predict treatment response in COQ8A-related ataxia and highlight the potential of pathophysiology-orientated neuroimaging evidence to inform treatment decisions.