Altered interhemispheric functional connectivity in patients with anisometropic and strabismic amblyopia: a resting-state fMRI study.
OBJECTIVE
Altered brain functional connectivity has been reported in patients with amblyopia by recent neuroimaging studies. However, relatively little is known about the alterations in interhemispheric functional connectivity in amblyopia. The present study aimed to investigate the functional connectivity patterns between homotopic regions across hemispheres in patients with anisometropic and strabismic amblyopia under resting state.


METHODS
Nineteen monocular anisometropic amblyopia (AA), 18 strabismic amblyopia (SA), and 20 normal-sight controls (NC) were enrolled in this study. After a comprehensive ophthalmologic examination, resting-state fMRI scanning was performed in all participants. The pattern of the interhemispheric functional connectivity was measured with the voxel-mirrored homotopic connectivity (VMHC) approach. VMHC values differences within and between three groups were compared, and correlations between VMHC values and each the clinical variable were also analyzed.


RESULTS
Altered VMHC was observed in AA and SA patients in lingual gyrus and fusiform gyrus compared with NC subjects. The altered VMHC of lingual gyrus showed a pattern of AA > SA > NC, while the altered VMHC of fusiform gyrus showed a pattern of AA > NC > SA. Moreover, the VMHC values of lingual gyrus were positively correlated with the stereoacuity both in AA and SA patients, and the VMHC values of fusiform gyrus were positively correlated with the amount of anisometropia just in AA patients.


CONCLUSIONS
These findings suggest that interhemispheric functional coordination between several homotopic visual-related brain regions is impaired both in AA and SA patients under resting state and revealed the similarities and differences in interhemispheric functional connectivity between the anisometropic and strabismic amblyopia.
Department of Radiology, Southwest Hospital, Third Military Medical University, 30 Gaotanyan Street, Shapingba District, Chongqing, 400038, People's Republic of China.
Minglong
M
Liang
Department of Radiology, Southwest Hospital, Third Military Medical University, 30 Gaotanyan Street, Shapingba District, Chongqing, 400038, People's Republic of China.
Bing
B
Xie
Ophthalmology Research Center, Southwest Eye Hospital/Southwest Hospital, Third Military Medical University, Chongqing, China.
Hong
H
Yang
Department of Radiology, Southwest Hospital, Third Military Medical University, 30 Gaotanyan Street, Shapingba District, Chongqing, 400038, People's Republic of China.
Xuntao
X
Yin
Ophthalmology Research Center, Southwest Eye Hospital/Southwest Hospital, Third Military Medical University, Chongqing, China.
Hao
H
Wang
Department of Radiology, Southwest Hospital, Third Military Medical University, 30 Gaotanyan Street, Shapingba District, Chongqing, 400038, People's Republic of China.|Department of Radiology, 401st Hospital of PLA, Qingdao, China.
Longhua
L
Yu
Department of Psychology, University of Minnesota Twin Cities, Minneapolis, MN, USA.
Sheng
S
He
Department of Radiology, Southwest Hospital, Third Military Medical University, 30 Gaotanyan Street, Shapingba District, Chongqing, 400038, People's Republic of China. wangjian_811@yahoo.com.
Jian
J
Wang
D000550:Amblyopia / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods*; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D055815:Young Adult
Amblyopia; Anisometropic; Resting-state fMRI; Strabismic; VMHC