Functional Alterations in Resting-State Visual Networks in High-Tension Glaucoma: An Independent Component Analysis

Abstract

Background: High-tension glaucoma (HTG) is the most common type of primary open angle glaucoma and elevated intraocular pressure (IOP) is the major risk factor of the disease. The aim of this study was to assess alterations in resting-state visual networks in patients with HTG and investigate the effect of elevated IOP on the visual networks. Methods: T1-weighted and resting-state functional MRI images were acquired from 36 HTG patients (aged 49.22 ± 15.26 years) and 20 healthy controls (aged 49.90 ± 5.62 years). Group independent component analysis (ICA) was utilized to evaluate altered functional connectivity (FC) in resting-state visual networks between HTG patients and healthy controls. Pearson correlation analysis between mean IOP and altered FCs in the visual networks was performed. Results: ICA demonstrated decreased FCs in HTG group in the left calcarine cortex of the lateral visual network, in the bilateral lingual gyrus of the medial visual network and in the bilateral lingual gyrus of the occipital visual network compared with healthy controls. Furthermore, correlation analysis revealed negative correlation between mean IOP and altered FC within the lateral visual network. Conclusion: The results suggested reduced FCs between primary and higher visual cortices in HTG brain. The IOP elevation might be responsible for the functional alterations in the visual networks.

Altered Static and Dynamic Interhemispheric Resting-State Functional Connectivity in Patients With Thyroid-Associated Ophthalmopathy

“…The occipital cortex is well known to be responsible for visual processing, mainly associated with visual formation and visual perception activities ( Yu et al, 2017 ). Specifically, CAL is the seat of primary visual cortex (V1) which receives direct visual inputs from the eyes via thalamic relays ( Lu et al, 2019 ), LG is within the visual recognition network involved in encoding visual memories ( Mao et al, 2020 ; Wang et al, 2020 ), and MOG is part of the dorsal visual areas which also plays a role in processing visual perception ( Tu et al, 2013 ; Shao et al, 2019 ). Reduced VMHC in these regions have been reported in glaucoma ( Wang et al, 2018 ), amblyopia ( Liang et al, 2017 ), blindness ( Shao et al, 2018 ), and globe injury ( Ye et al, 2018 ), consistently interpreted as disturbed interhemispheric functional synchronization in visual cortices.…”

Physical training and ocular yogic exercise in home: good alternative options to control the high-tension form of primary open angle glaucoma during the repeated COVID-19 waves

“…Glaucoma is caused by diabetes mellitus, aging, black ethnicity, and family history, but the most important modifiable risk factor is elevated intraocular pressure (IOP). The most common type of glaucoma-inducing irreversible blindness, high-tension primary open angle glaucoma (HTPOAG), is described by an IOP > 21 mmHg and an open angle of the anterior chamber of the eye [1].…”

Binocular Integrated Visual Field Deficits Are Associated With Changes in Local Network Function in Primary Open-Angle Glaucoma: A Resting-State fMRI Study

“…Structural changes were observed in several studies that compared glaucoma participants to healthy controls, showing altered white matter tracts and gray matter atrophy in brain areas involved in visual processing (Chen et al, 2013 ; Frezzotti et al, 2014 ; Wang et al, 2016a ; Giorgio et al, 2018 ). Moreover, several functional magnetic resonance imaging (fMRI) studies have shown altered cortical activity in glaucoma patients (Qing et al, 2010 ; Gerente et al, 2015 ; Jiang et al, 2017 ; Wang et al, 2020 ). It is largely unknown how these anatomical and functional changes affect the integrity of cortical functional networks and how, in turn, changes in these networks affect visual functioning of patients.…”