Reduction of R2 in the Basal Ganglia of Restless Legs Syndrome: a Biomarker for Iron Deficiency

Introduction: Restless legs syndrome (RLS) is a neurological disorder with a prevalence of about 5-10% of the general population. Its clinical symptom is characterized by uncontrollable, unbearable urges to move the legs, causing chronic sleep deprivation. The iron deficiency has been considered an important contributing factor for RLS [1]. In vivo iron evaluation for RLS has largely utilized T2 (=1/R2). However, other confounding factors such as water contents and diffusion may result in changes in tissue T2. Tissue iron content is known to be more specifically associated with tissue R2(=1/T2). The purpose of this study is two-fold: 1) to determine the sensitivity of R2 mapping method for the detection of the iron deficiency in RLS, and 2) to determine abnormal R2 distribution in the nigrostriatal dopaminergic pathway.