Erythropoietin (EPO) is known as a hormone for erythropoiesis in response to anemia and hypoxia. However, the effect of EPO is not only limited to hematopoietic tissue. Several studies have highlighted the neuroprotective function of EPO in extra-hematopoietic tissues, especially the retina. EPO could interact with its heterodimer receptor (EPOR/βcR) to exert its anti-apoptosis, anti-inflammation and anti-oxidation effects in preventing retinal ganglion cells death through different intracellular signaling pathways. In this review, we summarized the available pre-clinical studies of EPO in treating glaucomatous optic neuropathy, optic neuritis, non-arteritic anterior ischemic optic neuropathy and traumatic optic neuropathy. In addition, we explore the future strategies of EPO for optic nerve protection and repair, including advances in EPO derivates, and EPO deliveries. These strategies will lead to a new chapter in the treatment of optic neuropathy.

Glaucoma can cause irreversible vision loss and is the second leading cause of blindness worldwide. The disease mechanism is complex and various factors have been implicated in its pathogenesis, including ischemia, excessive oxidative stress, neurotropic factor deprivation, and neuron excitotoxicity. Erythropoietin (EPO) is a hormone that induces erythropoiesis in response to hypoxia. However, studies have shown that EPO also has neuroprotective effects and may be useful for rescuing apoptotic retinal ganglion cells in glaucoma. This article explores the relationship between EPO and glaucoma and summarizes preclinical experiments that have used EPO to treat glaucoma, with an aim to provide a different perspective from the current view that glaucoma is incurable.

Erythropoietin (EPO) is a circulating hormone conventionally considered to be responsible for erythropoiesis. In addition to facilitating red blood cell production, EPO has pluripotent potential, such as for cognition improvement, neurogenesis, and anti-fibrotic, anti-apoptotic, anti-oxidative, and anti-inflammatory effects. In human retinal tissues, EPO receptors (EPORs) are expressed in the photoreceptor cells, retinal pigment epithelium, and retinal ganglion cell layer. Studies have suggested its potential therapeutic effects in many neurodegenerative diseases, including glaucoma. In this review, we discuss the correlation between glaucoma and EPO, physiology and potential neuroprotective function of the EPO/EPOR system, and latest evidence for the treatment of glaucoma with EPO.

Corneal epithelial healing after refractive surgery is a clinically significant issue, especially for surface ablation procedures, and this can be monitored using optical coherence tomography (OCT). The aim of this work is to investigate the corneal epithelial thickness and irregularity by OCT after transepithelial photorefractive keratectomy (t-PRK) and analyse its correlation with visual and refractive outcomes. Patients aged ≥18 years with myopia, with or without astigmatism, who underwent t-PRK between May 2020 and August 2021 were included. All participants were subjected to complete ophthalmic examinations and OCT pachymetry at every follow-up visit. Patients were followed up at 1 week and 1, 3, and 6 months postoperatively. A total of 67 patients (126 eyes) were enrolled in this study. One month postoperatively, spherical equivalent refraction and visual acuity achieved preliminary stability. However, central corneal epithelial thickness (CCET) and standard deviation of the corneal epithelial thickness (SD_cet) took 3–6 months to progressive recovery. Patients with higher baseline spherical equivalent refraction were associated with slower epithelial recovery. At every follow-up time point, a significant superior-inferior difference in the minimum corneal epithelial thickness area was observed. Higher stromal haze was correlated with higher spherical equivalent refraction (both baseline and residual) but had no relation with visual outcomes. There was a significant correlation between higher CCET with a better uncorrected distance visual acuity and lower corneal epithelial thickness irregularity. CCET and SD_cet measured by OCT seem to be a good auxiliary indicator for reflecting the status of corneal wound recovery after t-PRK surgery. However, a well-designed randomised control study is needed to confirm the study results.

Many studies have demonstrated an increased cardiovascular (CV) risk in ankylosing spondylitis (AS) patients. Nevertheless, the influence of an endophthalmitis episode toward the future risks of acute myocardial infarction (AMI) in AS patients has been unclear. The objective of this study was to explore the impact of endophthalmitis on AMI risk in this particular patient population by a population-based retrospective cohort study with a follow-up period up to 16 years. Univariate and multivariate Cox regression analyses were used for the risk evaluation and the results were presented as crude and adjusted hazard ratios (HRs). Overall, we enrolled 557 AS patients with endophthalmitis as the study cohort and selected another 2228 matched AS patients without endophthalmitis as the comparison cohort. Comparing the comparison cohort, the study cohort showed a significantly higher overall AMI incidence rate with an adjusted HR of 1.631 (p < 0.001). In conclusion, endophthalmitis increased the risk of AMI in AS patients after adjusting for possible clinical confounders. Special attention and work-up are required for physicians when encountering a history of endophthalmitis in these special patient populations, especially when they are comorbid with other potential CV risk factors.

Objectives: To evaluate the impact of a new orthokeratology (OrthoK) lens on corneal epithelial thickness and higher-order aberrations (HOAs). Methods: This three-arm, prospective, crossover study randomly assigned participants to the control group, T1 group (1.5× control-group lens-design reverse curve [RC] height), and T2 group (2× control-group lens-design RC height). Participants underwent basic ophthalmological examinations, corneal topography, and corneal epithelial thickness and HOA measurements at each visit. Corneal zones were analyzed based on topographic changes induced by lens wear, corresponding to the central treatment zone and the reverse zone. Results: The spherical equivalent was significantly lower in T1 and T2 than in the control group on days 7 and 28 of lens wear (P<0.001). The corneal curvature was noticeably flatter in T1 and T2 than in the control group. No significant differences were observed among groups in the epithelial thickness of the central treatment zone after OrthoK lens wear. However, epithelial thickness in the reverse zone was significantly greater (P<0.05) in T1 and T2 compared with the control group after 28 days of lens wear. A significant difference in HOA was observed among the three groups after OrthoK lens wear for 1 and 7 days (P<0.01). T2 demonstrated higher levels of HOA than the other groups. Conclusions: This new design of OrthoK can alter the corneal epithelium thickness and stabilize central corneal flattening, thereby achieving a better correction for myopia. However, this design also induces HOAs and is associated with a mild but significant compromise in uncorrected visual acuity compared with conventional designs. Therefore, clinicians should weigh the potential benefits of myopia control against the associated effects on visual quality when selecting OrthoK lens designs.