title: A resting-state fMRI study on early-stage drug-naïve Parkinson's disease patients with drooling.
abstract: OBJECTIVE
  Drooling is a common symptom in Parkinson's disease (PD). This study used resting-state functional MRI (fMRI) to evaluate the brain connectivity of cortico-striatal circuits in PD patients with drooling.
  
  
  METHODS
  We enrolled 30 early-stage drug-naïve PD patients and 30 matched normal controls. Among the PD patients, 15 patients were classified as "droolers" with the presence of drooling and 15 patients as "non-droolers" with the absence of drooling. All participants underwent resting-state fMRI scans on a 3-T MR system, focusing on the functional connectivity of striatum subregions.
  
  
  RESULTS
  Compared with PD patients without drooling, PD patients with drooling showed the significantly reduced functional connectivity of putamen within bilateral sensorimotor cortices, superior and inferior parietal lobules and areas in the right occipital and temporal lobes. No increased functional connectivity was found between the two PD subgroups. In addition, compared with healthy controls, both PD subgroups showed the functional connectivity alterations in cortico-striatal loops. The decreased functional connectivity was prominent in the most affected posterior putamen, and the increased functional connectivity was evident only in the relatively unaffected anterior striatum and caudate.
  
  
  CONCLUSIONS
  By studying a cohort of early-stage drug-naïve PD patients, we eliminated the potential confounding effects of antiparkinson medication on the functional integration of neural networks. We demonstrated decreased connectivity within cortico-striatal networks in PD patients with drooling. These findings might be helpful for promoting the further understanding of neural system effects underlying drooling in PD. Our result is preliminary and further investigation is needed.
authors.affiliation: Department of neurology, West China Hospital, Sichuan University, Chengdu, Sichuan University, China.
authors.forename: Yanbing
authors.initials: Y
authors.lastname: Hou
authors.affiliation: Department of neurology, West China Hospital, Sichuan University, Chengdu, Sichuan University, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Luo
authors.affiliation: Department of neurology, West China Hospital, Sichuan University, Chengdu, Sichuan University, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of neurology, West China Hospital, Sichuan University, Chengdu, Sichuan University, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.affiliation: Department of neurology, West China Hospital, Sichuan University, Chengdu, Sichuan University, China.
authors.forename: Ruwei
authors.initials: R
authors.lastname: Ou
authors.affiliation: Department of neurology, West China Hospital, Sichuan University, Chengdu, Sichuan University, China.
authors.forename: Wanglin
authors.initials: W
authors.lastname: Liu
authors.affiliation: Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China. Electronic address: huaxigong@126.com.
authors.forename: Qiyong
authors.initials: Q
authors.lastname: Gong
authors.affiliation: Department of neurology, West China Hospital, Sichuan University, Chengdu, Sichuan University, China. Electronic address: hfshang2002@126.com.
authors.forename: Huifang
authors.initials: H
authors.lastname: Shang
mesh_terms: D001931:Brain Mapping; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology*; D012798:Sialorrhea / Q000503:physiopathology*
keywords: Drooling; Functional connectivity; Parkinson’s disease; Striatum; fMRI