Intravitreal injection of anti-vascular endothelial growth factor (VEGF) drugs is the main treatment for diabetic macular edema (DME), however, 30% of patients still respond poorly to its treatment. At present, imaging markers that can indicate the prognosis of anti-VEGF drug treatment include ischemic index, deep retinal capillary plexus foveal avascular zone area, number of microaneurysms, blood flow density, disorder of the inner retinal layer, outer membrane and/or the degree of damage to the ellipsoid zone, strong reflex foci, intraretinal cysts, subretinal fluid. Biomarkers include high-sensitivity C-reactive protein, neutrophil to lymphocyte ratio, anti-fumarase antibody, intraocular aqueous humor cell adhesion molecule-1, interleukin (IL)-6, IL-8, etc. Understanding these clinical markers that may predict and evaluate the prognosis of anti-VEGF drug therapy can be beneficial to adjust the treatment plan, and more effectively monitor, treat, and manage DME patients.
The mechanisms behind diabetic retinopathy (DR) can be ascribed primarily to retinal microvascular abnormalities, excessive inflammatory response and neurodegeneration. Circular RNA (circRNA) is a type of endogenous non-coding RNA with a special circular structure, which is mainly composed of precursor RNA after shearing and processing. It is widely present in the retina and participates in the occurrence and development of various fundus diseases. CircRNAs express in an abnormal way in retina, serving as “the sponge” for miRNA so as to play roles in dysfunction of retinal vascular, inflammatory response and neurodegeneration in the development of DR. Further studies for circRNAs in DR will illustrate pathophysiology of DR more deeply, shedding light on circRNAs becoming novel biomarkers and molecular targets for diagnosis and treatment, thus achieving the goal of early diagnosis and precise therapy of DR.