Clinical, Neuroimaging and Neurophysiologic Evidences of Restless Legs Syndrome as a Disorder of Central Nervous System

하지불안증후군이 중추신경계 질환임을 시사하는 임상적, 신경영상학적, 신경생리학적 증거들에 관하여

Restless legs syndrome (RLS) is a sensorimotor neurological disorder in which the primary symptom is a compelling urge to move the legs, accompanied by unpleasant and disturbing sensations in the legs. Although pathophysiologic mechanism of RLS is still unclear, several evidences suggest that RLS is related to dysfunction in central nervous system involving brain and spinal cord. L-DOPA, as the precursor of dopamine, as well as dopamine agonists, plays an essential role in the treatment of RLS leading to the assumption of a key role of dopamine function in the pathophysiology of RLS. Patients with RLS have lower levels of dopamine in the substantia nigra and respond to iron administration. Iron, as a cofactor in dopamine production, plays a central role in the etiology of RLS. Functional neuroimaging studies using PET and SPECT support a central striatal D2 receptor abnormality in the pathophysiology of RLS. Functional MRI suggested a central generator of periodic limb movements during sleep (PLMs) in RLS. However, to date, we have no direct evidence of pathogenic mechanisms of RLS.