Brain iron accumulation kinetics in Parkinson’s disease revealed by relaxometry network and susceptibility-weighted imaging

Motivation: Iron deposition is implicated in the pathogenesis of Parkinson's disease (PD). However, most of the previous studies failed to report progressive iron accumulation with disease progression. Goal(s): This study aimed to explore the kinetics of iron accumulation in the PD brain using a novel relaxometry covariance network (RCN) approach. Approach: The RCN approach consisted of three steps, the identification of brain regions as propagators of iron, construction of causal RCN and individual differential RCN. Results: The left substantia nigra pars reticulata, left substantia nigra pars compacta, and lobule VII of cerebellum vermis were identified as propagators of iron. Impact: The application of our novel relaxometry covariance network on susceptibility-weighted imaging revealed iron accumulation kinetics in Parkinson's disease, which were closely related to the pathophysiological aspects of the disease. The current findings deserved further exploration to elucidate the underlying mechanisms.