title: Intrinsic Functional Connectivity Alterations of the Primary Visual Cortex in Primary Angle-Closure Glaucoma Patients before and after Surgery: A Resting-State fMRI Study.
abstract: OBJECTIVE
  To investigate the altered intrinsic functional connectivity (iFC) of the primary visual cortex (V1) in primary angle-closure glaucoma (PACG) patients before and after surgery using resting-state functional MRI.
  
  
  METHODS
  Twenty-five preoperative PACG (pre-PACG) patients and 25 well-matched healthy controls (HCs) were included in this study, and 9 PACG patients were assessed again at least 3 months after treatment (post-PACG). We generated the iFC maps of the seed regions in the centers of the left and right V1 and conducted group comparisons. Then, the relationships between the altered iFC coefficients and clinical variables were investigated in the pre-PACG patients.
  
  
  RESULTS
  Compared with the HCs, the pre-PACG patients showed decreased iFC between the left V1 and right V2 (covering the cuneus, calcarine and lingual gyrus) and increased iFC between the left V1 and left temporal-parietal region, left frontal opercula-insula-basal ganglia region, right insula-basal ganglia region, and right inferior parietal lobule (P < 0.01, corrected). Compared with the pre-PACG patients, the post-PACG patients showed increased iFC between the left V1 and bilateral V2, and between the left V1 and left or right postcentral gyrus; in addition, they showed decreased iFC between the left V1 and the dorsal-attention and frontoparietal-control networks. In the pre-PACG patients, visual activity (VA) was positively correlated with increased iFC between the left V1 and the left temporal-parietal region or the right inferior parietal lobule. Similar patterns of alterations were observed in the right V1-iFC in both the pre- and post-PACG patients.
  
  
  CONCLUSIONS
  The primary findings have demonstrated a gradual decrease in visual information integration in the left V1-V2 pathway and VA-related functional compensation in the pre-PACG patients, generating further evidence of functional restoration in post-PACG patients.
authors.affiliation: Department of Radiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi Province, China.
authors.forename: Shenghong
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Radiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi Province, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.affiliation: Department of Radiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi Province, China.|Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi Province, China.
authors.forename: Honghan
authors.initials: H
authors.lastname: Gong
authors.affiliation: Department of Radiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi Province, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Jiang
authors.affiliation: Department of Radiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi Province, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Liu
authors.affiliation: Department of Radiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi Province, China.
authors.forename: Fengqin
authors.initials: F
authors.lastname: Cai
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi Province, China.
authors.forename: Chonggang
authors.initials: C
authors.lastname: Pei
authors.affiliation: Department of Radiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi Province, China.|Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi Province, China.
authors.forename: Fuqing
authors.initials: F
authors.lastname: Zhou
authors.affiliation: Department of Radiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi Province, China.|Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi Province, China.
authors.forename: Xianjun
authors.initials: X
authors.lastname: Zeng
mesh_terms: D000328:Adult; D000368:Aged; D001931:Brain Mapping; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000000981:diagnostic imaging* / Q000601:surgery; D012146:Rest / Q000502:physiology; D016896:Treatment Outcome; D014793:Visual Cortex / Q000000981:diagnostic imaging* / Q000503:physiopathology