Yeong Seon Lee1, Jeonghun Ku2, Keun Tae Kim1, HyukWon Chang3, Christopher J Earley4, Richard P Allen4, Yong Won Cho5. 1. Department of Neurology Dongsan Medical Center, Keimyung University School of Medicine, Daegu, South Korea. 2. Department of Biomedical Engineering Dongsan Medical Center, Keimyung University School of Medicine, Daegu, South Korea. Electronic address: jeonghun.ku@gmail.com. 3. Department of Radiology Dongsan Medical Center, Keimyung University School of Medicine, Daegu, South Korea. 4. Department of Neurology, Johns Hopkins University, Hopkins Bayview Medical Center, Baltimore, MD, USA. 5. Department of Neurology Dongsan Medical Center, Keimyung University School of Medicine, Daegu, South Korea. Electronic address: neurocho@gmail.com.
Abstract
OBJECTIVES: Resting-state brain connectivity has been shown to differ for Restless Legs Syndrome (RLS) compared to healthy control (CON) groups. This study evaluates the degree these RLS-CON differences are changed by concurrent treatment. METHODS: Resting-state functional MRIs were obtained from 32 idiopathic RLS patients during the morning asymptomatic period and 16 age and gender-matched CON subjects. Of the 32 RLS patients, 16 were drug-naïve (DN-RLS), and 16 were regularly drug-treated using a dopamine agonist (DT-RLS). Various assessments of disease characteristics were also performed. The primary purpose was to assess the replicability of prior results and the effects of treatment on these differences between controls and untreated RLS patients. Resting-state connectivity was analyzed by a seed-based method using the bilateral ventral-posterolateral nuclei (VPLN) in the thalamus. RESULTS: In the DN-RLS group, compared to the CON group, three areas (the bilateral lingual gyri and right middle temporal gyrus) were replicated. The three replicated areas did not significantly differ for DT-RLS compared to DN-RLS. DT-RLS compared to DN-RLS had significantly higher thalamic connectivity for the left uvula, right tuber, left anterior insula, and right declive. CONCLUSIONS: Thalamic connectivity to the bilateral lingual gyri and right middle temporal gyrus is a replicable finding in DN-RLS that was not affected by dopamine agonist treatments. Other changes in thalamic connectivity were altered by dopamine agonist treatment. These treatment effects may be pertinent to the known treatment benefits of a dopamine agonist on RLS symptoms.
OBJECTIVES: Resting-state brain connectivity has been shown to differ for Restless Legs Syndrome (RLS) compared to healthy control (CON) groups. This study evaluates the degree these RLS-CON differences are changed by concurrent treatment. METHODS: Resting-state functional MRIs were obtained from 32 idiopathic RLSpatients during the morning asymptomatic period and 16 age and gender-matched CON subjects. Of the 32 RLSpatients, 16 were drug-naïve (DN-RLS), and 16 were regularly drug-treated using a dopamine agonist (DT-RLS). Various assessments of disease characteristics were also performed. The primary purpose was to assess the replicability of prior results and the effects of treatment on these differences between controls and untreated RLSpatients. Resting-state connectivity was analyzed by a seed-based method using the bilateral ventral-posterolateral nuclei (VPLN) in the thalamus. RESULTS: In the DN-RLS group, compared to the CON group, three areas (the bilateral lingual gyri and right middle temporal gyrus) were replicated. The three replicated areas did not significantly differ for DT-RLS compared to DN-RLS. DT-RLS compared to DN-RLS had significantly higher thalamic connectivity for the left uvula, right tuber, left anterior insula, and right declive. CONCLUSIONS: Thalamic connectivity to the bilateral lingual gyri and right middle temporal gyrus is a replicable finding in DN-RLS that was not affected by dopamine agonist treatments. Other changes in thalamic connectivity were altered by dopamine agonist treatment. These treatment effects may be pertinent to the known treatment benefits of a dopamine agonist on RLS symptoms.