ABSTRACT
Maculopathy caused by various fundus diseases in the late stage is a common cause of low vision. Medical technology is difficult to reverse the loss of macular function currently, so interventions that help improve the visual system, utilize residual visual function, and improve quality of life deserve attention. Damage to the fovea of the macula does not mean that the entire retinal function is impaired. There may be one or more retinal regions adjacent to the fovea that can serve as a fixation center. It is possible to form stable paracentral fixation, complete functional remodeling of the visual system, and effectively utilize residual visual function by taking appropriate training on these potential paracentral fixation points for most patients. In 2021, a clinical guideline has been published for low vision rehabilitation in China. In order to strengthen the precise management of diseases and develop a standard operating procedure for visual training specifically for patients with low vision due to macular disease, the National Clinical Research Center for Eye Diseases initiated and organized relevant domestic experts, utilizing the latest research experience at home and abroad, and through repeated discussions, this consensus (International Practice Guideline Registration Number: PREPARE-2023CN199) was formed as a reference for ophthalmologists, optometrists and rehabilitation physicians in their clinical research and practice.
ABSTRACT
@#In clinical practice, many macular diseases in advanced stages such as age-related macular degeneration(ARMD)and Stargardt disease are manifested reduced visual acuity, unstable and even paracentral fixation resulting from the central scotoma followed by the scarring of neovascular fibres or the impairment of photoreceptors and retinal pigment epithelium, which cause great distress to patients' life, work and psychology. For a long time, there have been limited rehabilitation treatments for such patients. However, recent articles have indicated that biofeedback training by using microperimetry is expected to enhance neurosensory adaptation by achieving cortical plasticity, and makes better use of residual retinal function to help those with low vision associated with central scotoma consolidate or establish stable central or paracentral fixation, thereby improving visual function including visual acuity and reading speed. In order to improve the understanding of this rehabilitation therapy, this article will overview the mechanism and protocol of microperimetric biofeedback training(MBFT), the selection of the preferred retinal locus, the clinical application in macular diseases and its prospects.
ABSTRACT
In macular diseases,there is a typical development of a central scotoma which is responsible for the central visual acuity loss,reading speed reduction and changing in fixation stability.The prevention and treatment of degenerative macular disease have not yet received satisfying functional results.Effectiveness of biofeedback treatment in visual rehabilitation has been evidenced in several studies.The microperimeter can improve their visual abilities and lay the basis for new,more manageable visual aids by using cerebral plasticity and neurosensorial adaptation to the central scotoma of patients with macular diseases.The purpose of this review is to summarize key fmdings on characteristics of central scotoma,the plasticity of human visual system and visual rehabilitation via microperimetry.
ABSTRACT
Microperimetry‑1 (MP‑1) evaluation and MP‑1 biofeedback training were done in a case of bilateral myopic macular degeneration with a central scotoma. Fixation behavior, location and stability of preferred retinal locus, eye movement speed, and mean sensitivity were assessed. The mean retinal sensitivities before, after and at 1‑year after training in the right eye were 2.9 dB, 2.9 dB and 3.7 dB and in the left eye were 3.5 dB, 3.7 dB and 1.8 dB. The fixation point in the 2° gravitation circle, improved from 40% to 50% in the right eye and from 43% to 67% in the left eye. The average eye speed before, after and at 1‑year after training in right eye were 0.19°/s, 0.26°/s and 0.25°/s and in left eye were 0.36°/s, 0.25°/s and 0.27°/s. Thus, biofeedback training using MP‑1 can improve the visual function in patients with macular diseases and central scotoma.
ABSTRACT
PURPOSE: The definition of eccentric viewing (EV) is using non-foveal preferred retinal loci (PRL) for viewing. The purpose of the present study was to investigate the clinical effect of EV training for low vision rehabilitation in patients with central scotomas. METHODS: The direction of EV was monitored in 30 low vision patients with central scotomas by moving the patient's view. The PRL was found by using a direct ophthalmoscope and retinal camera; the preserved visual field was identified using a kinetic visual field analyzer. The relationships between EV, PRL, and visual field were evaluated. The patients and their guardians were educated regarding EV. After 2 weeks of self-training, maintenance of EV was checked and changes in best-corrected visual acuity (BCVA), reading speed, and satisfaction questionnaire were evaluated. RESULTS: A relationship between EV, PRL, and visual field was in accordance in half of the patients. There were no significant differences in demographics and basic visual characteristics in patients where the relationship was not in accordance. EV was maintained in two-thirds of the patients, but there were no significant differences in demographics and basic visual characteristics in patients who discontinued EV. There were no significant improvements in BCVA; however, reading speed and the satisfaction scores increased significantly with EV. CONCLUSIONS: The direction of EV was effectively detected by convenient access using an inexpensive method. Functional vision and satisfaction significantly improved following EV training. EV training can be used as an effective method for low vision rehabilitation in patients with central scotomas.