Altered intrinsic regional spontaneous brain activity in patients with optic neuritis: a resting-state functional magnetic resonance imaging study

Abstract

ObjectiveTo investigate the underlying regional homogeneity (ReHo) in brain-activity deficit in patients with optic neuritis (ON) and its relationship with behavioral performance.Materials and methodsIn total, twelve patients with ON (four males and eight females) and twelve (four males and eight females) age-, sex-, and education-matched healthy controls underwent resting-state functional magnetic resonance imaging scans. The ReHo method was used to assess the local features of spontaneous brain activity. Correlation analysis was used to explore the relationship between the observed mean ReHo values of the different brain areas and the visual evoked potential (VEP) in patients with ON.ResultsCompared with the healthy controls, patients with ON showed lower ReHo in the left cerebellum, posterior lobe, left middle temporal gyrus, right insula, right superior temporal gyrus, left middle frontal gyrus, bilateral anterior cingulate cortex, left superior frontal gyrus, right superior frontal gyrus, and right precentral gyrus, and higher ReHo in the cluster of the left fusiform gyrus and right inferior parietal lobule. Meanwhile, we found that the VEP amplitude of the right eye in patients with ON showed a positive correlation with the ReHo signal value of the left cerebellum posterior lobe (r=0.701, P=0.011), the right superior frontal gyrus (r=0.731, P=0.007), and the left fusiform gyrus (r=0.644, P=0.024). We also found that the VEP latency of the right eye in ON showed a positive correlation with the ReHo signal value of the right insula (r=0.595, P=0.041).ConclusionON may involve dysfunction in the default-mode network, which may reflect the underlying pathologic mechanism.

Altered intrinsic regional brain spontaneous activity in patients with comitant strabismus: a resting-state functional MRI study

“…The 240 functional images were analyzed as described previously. 17 Briefly, the data were filtered by MRIcro (Nottingham University, Nottingham, UK) and preprocessed using SPM8 (The MathWorks, Inc., Natick, MA, US) and DPARSFA (Institute of Psychology, CAS., Beijing, People’s Republic of China) software. Then, the data were processed with slice timing, head motion correction, spatial normalization, and smoothening with a Gaussian kernel of 6×6×6 mm 3 full-width at half-maximum (FWHM).…”

“…Based on Kendall’s coefficient of concordance (KCC), ReHo computation was performed with the REST software (Center for Cognition and Brain Disorders, HZNU., Hangzhou, Zhejiang, People’s Republic of China), as previously described. 17 …”

“…The regional homogeneity (ReHo) method, a resting-state fMRI (rs-fMRI) measurement method, is widely used to determine the local synchronization of spontaneous fMRI signals, and it provides important information on the activities of the brain. 15 , 16 The ReHo method has been successfully deployed to investigate pathological mechanisms of neural diseases such as optic neuritis, 17 sleep disorders, 18 and Parkinson’s disease. 19 However, it has not yet been used to explore the pathophysiological changes in comitant strabismus (CS).…”

Recent advances in magnetic resonance imaging of optic neuritis

“…Diffusion tensor imaging (DTI) is an extension of DWI that can be utilized to assess the integrity of the white matter of the optic nerve in vivo by using tractography related to specific white matter tracts [24]. Fractional anisotropy [25] ranging from 0.0 to 1.0 is a commonly used parameter that reflects the consistency of water molecules in the direction of motion in a voxel, which is altered by the integrity of the structure and the consistency of the arrangement of fiber bunches [26]. The higher 1 3…”

“…Blood oxygenation level-dependent functional MRI can depict cerebral cortex activity using blood flow information. Shao [25] reported that ON involved the defaultmode network on resting-state functional magnetic resonance imaging. Huang [35] came to a similar conclusion using amplitude of low-frequency fluctuation.…”