Since anti-vascular endothelial growth factor (VEGF) therapy has recently become the first-line treatment of wet age related macular degeneration in China, as well as retinopathy of prematurity, neovascular glaucoma and macular edema secondary to diabetic retinopathy or retinal vein occlusion in other countries. It is worth thinking about that how to perform anti-VEGF treatment properly to benefit more patients. We reviewed the fields of clinical researches to explore the best role of anti-VEGF treatment in prevention and treatment of retinal disease in future.
There are lots of imaging technologies in the ocular fundus disease field, including ultrasound biomicroscopy (UBM), fundus fluorescein angiography (FFA), indocynine green angiography (ICGA), fundus photograph (FP) and Optical Coherence Tomography (OCT). However there is no standard for image formats among various fundus imaging equipment, technology application processes, thus the relevant data cannot be compared and analyzed. And improper operation of the instruments causes unstable image quality or image missing. Also lack of appropriate evaluation guidelines results in different interpretation of same image data. These three factors not only affect the fundus imaging device application efficiency, limit the sharing of fundus imaging resource, but also hinder the development of fundus imaging diagnostic applications. Therefore, instrument types, data acquisition protocol and data presenting formats should be standardized for ocular fundus image acquisition. The technicians who operate the machine should be trained regularly to follow the standard operating procedure of data acquiring, thus to ensure integrity, truthful and reliable data is collected. In order to enhance the application efficiency of fundus imaging equipment, save public health resources, to promote fundus imaging diagnostic technology development, we need to develop evaluation guidelines for fundus image data, establish a comprehensive system including remote consultation center, reading center and quality control center.
The mineralocorticoid receptor (MR) belongs to the nuclear receptor superfamily and is expressed in the retina and choroid. MR antagonist (MRA) has a long history of application in non-ophthalmic clinical practice. Various cellular and animal models indicated that inappropriate activation of MR participated in pathological angiogenesis, oxidative stress, inflammation, disturbance of ion/water homeostasis and neurodegenerative changes, while the application of MRA can reduce or reverse these pathological processes. After using MRA in central serous chorioretinopathy (CSC) patients, improved visual function, less subretinal fluid and reduced sub-foveal choroidal thickness were observed. Single nucleotide polymorphisms in MR and plasma aldosterone levels were significantly different between chronic CSC patients and CSC patients with spontaneous remission. Novel formulation for sustained-release MRA and the mechanisms involving inflammation may become the new focus of MR study. This review summarizes the research status of MR and MRA in order to provide a reference for future basic research and clinical treatment.
Retinal neuronal cells are crucial in the formation of vision. Injury or death of these cells may lead to irreversible damage to visual function due to their low regenerative capacity. The P2X7 receptor is a trimeric adenosine triphosphate (ATP)-gated cation channel. Recent studies have shown that P2X7 receptor plays a role in retinal neuronal death. In a series of animal models, when exposed to conditions of hypoxia or ischemia, elevated ocular pressure, trauma and exogenous agonists, P2X7 receptor activated by extracellular ATP can cause death of retinal neuronal cells such as retinal ganglion cells and photoreceptor cells through direct or indirect pathways. Blocking the expression and function of P2X7 receptor by its specific antagonist and gene knocking-out, the loss of retinal neuronal cells is significantly attenuated. P2X7 receptor may become a potential novel neuroprotective target for diseases related to the loss of retinal neurons.
Diabetic retinopathy (DR) is the leading cause of blindness in the working-age population, and it is a key ocular fundus disease that needs to be paid attention to in the next five years according to the "14th Five-Year" Plan for Eye Health. Promoting the systematic management of DR and constructing the chronic disease management system are the key to the next step of national eye health work. It is necessary to further improve the management mode of the whole course of DR patients with chronic eye disease through the joint action of medical security system at all levels, including strengthening supporting policies of primary medical institutions, optimizing medical service mode and process, strengthening scientific education to improve patients' and doctors' disease cognition, and updating authoritative Chinese DR guidelines to standardize diagnosis and treatment. It is hoped that the low vision and blindness caused by DR in China can be greatly reduced after the implementation of the "14th Five-Year" Plan for Eye Health.
The therapeutic response of anti-vascular endothelial growth factor (VEGF) differs among individuals. According to the changes of central retinal thickness, intraretinal fluid, subretinal fluid, best corrected visual acuity and other morphological or functional manifestations after treatment, the performance of the treated eyes can be classified as optimal response, poor response and non-response. A variety of factors could account for poor or non-response to anti-VEGF, such as genomic polymorphism and specific genomic risk alleles, lesion characteristics, vitreous and macular structural abnormalities, resistance to anti-VEGF drug, and the role of pericytes and others. The common counter measures include increasing the dosage, shortening the injection interval and replacing with another alternative drug, inhibition of pericytes, relieving vitreomacular anatomical abnormalities. It is still worthy of further exploration that how to assess individual reasons for non-response, so that we can give proper treatment to reduce the excessive use of anti-VEGF drugs and improve the clinical management of ocular neovascularization diseases.
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.