Microsaccade alteration in primary open-angle glaucoma and the effects in treatment induced by noninvasive transorbital Alternating Current Stimulation for vision restoration

Glaucoma is a progressive optic neuropathy associated with degeneration of retinal ganglion cells and their axons, which has an impact on complex daily behaviors, such as driving, walking, and eye-hand coordination, which may be affected by visual field defects (VFDs). Little is known about the underlying nature of the functional mechanisms influencing impairment from VFDs, but it seems likely that worsening of eye movements may play a role in this process.
Microsaccades (MS) are a kind of fixational eye movement. They play a significant role in counteracting foveal and peripheral fading. MS can be measured precisely with reliable parameters in recent years. Because of their important role in normal vision, it is reasonable to assume that MS are also affected in glaucoma patients.
Noninvasive, repetitive transorbital alternating current stimulation (rtACS), as a new method to enhance neuronal function both in normal subjects and in patients with some residual vision, was proved effective and safe in the treatment of glaucoma. Based on the theory about the role of MS in vision fixation it was of importance to investigate that whether MS could be one of the significant cause of the efficacy of vision restoration as induced by rtACS.
Therefore, the aim of this study will be to determine whether microsaccadic eye movements are altered in glaucoma patients and whether there are changes of MS-related parameters during the treatment for vision restoration induced by rtACS.