Altered Regional Homogeneity in Patients With Corneal Ulcer: A Resting-State Functional MRI Study

Abstract

Objective To investigate the potential regional homogeneity (ReHo) brain activity changes in patients with corneal ulcer (CU) and their possible relationship with clinical symptoms. Materials and Methods Forty patients with CU (26 men and 14 women), and 40 healthy controls (HCs) (26 men and 14 women) closely matched in age, sex, and weight underwent resting-state functional MRI scans, respectively. The ReHo method was applied to evaluate synchronous neural activity changes. Receiver operating characteristic curve (ROC curve) was used to show high test-retest stability and high degree of sensitivity and specificity. We utilized the correlation analysis to calculate the relationship between the average ReHo signal values in different brain areas and the clinical symptoms in CU patients. Results Compared with the HCs, CU patients had significantly increased ReHo values in right cerebellum posterior lobe, left cerebellum posterior lobe, left inferior temporal gyrus, right lingual gyrus, left middle frontal gyrus, left angular gyrus, left cingulate gyrus, right angular gyrus and bilateral superior frontal gyrus, and decreased ReHo values in right anterior cingulate and left precentral gyrus. ROC curve analysis of each brain regions showed the accuracy of AUC was perfect except the right cerebellum posterior lobe. Nevertheless, there was no clear evidence of prominent relevance between the average ReHo values in brain areas and the clinical symptoms. Conclusion Corneal ulcer caused dysfunctional adaption in different brain areas, which including relatively increased values and decreased values. This finding may help us take a further step in exploring the underlying pathologic mechanisms of CU.

Abnormal Regional Spontaneous Neural Activity in Nonarteritic Anterior Ischemic Optic Neuropathy: A Resting-State Functional MRI Study

“…In the present study, ROC analysis was applied to determine the reliability of using ReHo values to diagnose patients. Several neuroimaging studies focusing on ocular diseases have successfully applied ROC analyses to discriminate those with ocular disease from NCs [ 11 , 22 , 24 , 49 , 50 ]. According to these studies, the ability to discriminate conditions are considered excellent, moderate, fair, and failed when AUC values are 0.9–1, 0.7–09, 0.5–0.7, and less than 0.5, respectively [ 22 , 24 , 50 ].…”

Reduced Global-Brain Functional Connectivity of the Cerebello-Thalamo-Cortical Network in Patients With Dry Eye Disease

“…The most common method of noise reduction is smooth. The smooth method is also used in previous studies on ophthalmic diseases (Chen et al, 2017 ; Wang et al, 2017 ; Xu et al, 2019 ). The time series were further linearly detrended and temporally band-pass filtered (0.01–0.08 Hz).…”

“…Previous researches showed that patients with DED had extensive alterations in brain function, and abnormal brain function played an important role in the maintenance and development of dry eye symptoms (Rahman et al, 2015 ; Levitt et al, 2017 ). fMRI has been used to explore abnormal functional activity in eye diseases such as glaucoma, amblyopia and corneal ulcers (Lin et al, 2012 ; Li et al, 2014 ; Rahman et al, 2015 ; Chen et al, 2017 ; Wang et al, 2017 ; Xu et al, 2019 ). However, it remains unclear whether patients with DED have abnormal GFC in certain brain regions.…”

<p>Altered Intrinsic Functional Connectivity of the Primary Visual Cortex in Patients with Corneal Ulcer: A Resting-State fMRI Study</p>

“…Another study showed that patients with CU had markedly increased regional homogeneity (ReHo) values in the left middle frontal gyrus. 22 In addition, activation of FEF was reported in magnetic resonance studies of retinal detachment, 23 age-related macular degeneration, 24,25 progressive retinitis pigmentosa, 26 and macular hole 27 retinalrelated diseases. Consistent with previous studies, the increased FC values between the bilateral V1 and left and right middle frontal gyri shown in this study reflected the activation of visual processing, suggesting the plasticity that compensates for CU-related visual input deficits.…”