Background: This study aimed to determine the relationship between dyslipidemia and dry eye disease (DED) in a Korean population. Methods: This population-based study enrolled 5,627 adults (aged >19 years) who were participating in the first year of the fifth annual Korea National Health and Nutrition Examination Survey from 2010 to 2011. Clinically diagnosed DED and its symptoms were surveyed, and biochemical blood analysis data were collected. Dyslipidemia was defined as any of the following: hypercholesterolemia (total cholesterol > 200 mg/dL), hypertriglyceridemia (triglyceride > 150 mg/dL), low levels of high-density lipoprotein (100 mg/dL). Results: After adjusting for demographics (age and body mass index), lifestyle (smoking, drinking, exercise, and residential district), and medical factors (diabetes, hypertension, previous ophthalmic surgery, menopause, and rheumatologic disease), elevated serum cholesterol level was found to be associated with increased likelihood of DED (odds ratio, 1.77; 95% confidence interval, 1.127–2.78) in women. Conclusions: DED in a Korean population was found to be associated with high serum cholesterol levelsThe results of this study highlight the significance of eye examinations and independent lipid profile monitoring in patients with dyslipidemia because of its possible correlation with DED progression.

Recent studies suggested that an association exists between vision loss and cognitive impairment, although it is still vague whether there are causal relationships or direct association between low vision and dementia. We were to investigate the association between low vision and dementia in the Korean population using the National Health Insurance Service (NHIS) database. We analyzed the data of 6,029,657 subjects aged ≥40 years, drawn from Korea National Health Insurance Service. The hazard ratio (HRs) and 95% confidence interval (CIs) of dementia, Alzheimer’s disease (AD), and Vascular dementia (VD) were estimated using multivariable Cox proportional hazards regression models. Statistical analysis showed that subjects with more severe visual impairments have a higher risk of dementia, AD, and VD after adjusting for compounding variables. The HRs of dementia increased significantly as visual acuity worsened (HRs 1.444 [95% CIs 1.415–1.473] for visual acuity (VA) < 1.0, 1.734 [1.693–1.777] for VA < 0.3, 1.727 [1.686–1.770] for VA < 0.1 and 1.991[1.902–2.085] for visual loss). Baseline visual loss and visual impairment were positively associated with the risk of dementia, AD, and VD. From the results of this nationwide population-based cohort study, we suggest that there is a significant increase in the incidence of dementia in subjects with low vision.

To assess corneal inflammation from alkali chemical burns, we examined the therapeutic effects of in situ-forming hyaluronic acid (HA) hydrogels crosslinked via blue light-induced thiol-ene reaction on a rat corneal alkali burn model. Animals were divided into three groups (n = 7 rats per group): untreated, treated with 0.1% HA eye drops, and treated with crosslinked HA hydrogels. Crosslinking of HA hydrogel followed by the administration of HA eye drops and crosslinked HA hydrogels were carried out once a day from days 0–4. Corneal re-epithelialization, opacity, neovascularization, thickness, and histology were evaluated to compare the therapeutic effects of the three groups. Further investigation was conducted on the transparency of HA hydrogels to acquire the practical capabilities of hydrogel as a reservoir for drug delivery. Compared to untreated animals, animals treated with crosslinked HA hydrogels exhibited greater corneal re-epithelialization on days 1, 2, 4, and 7 post-injury (p = 0.004, p = 0.007, p = 0.008, and p = 0.034, respectively) and the least corneal neovascularization (p = 0.008). Histological analysis revealed lower infiltration of stromal inflammatory cells and compact collagen structure in crosslinked HA hydrogel-treated animals than in untreated animals. These findings corresponded with immunohistochemical analyses indicating that the expression of inflammatory markers such as α-SMA, MMP9, and IL1-β was lower in animals treated with crosslinked HA hydrogels than untreated animals and animals treated only with 0.1% HA eye drops. With beneficial pharmacological effects such as re-epithelization and anti-inflammation, in situ-forming hyaluronic acid (HA) hydrogels may be a promising approach to effective drug delivery in cases of corneal burn injuries.

The available treatment options include corneal transplantation for significant corneal defects and opacity. However, shortage of donor corneas and safety issues in performing corneal transplantation are the main limitations. Accordingly, we adopted the injectable in situ-forming hydrogels of collagen type I crosslinked via multifunctional polyethylene glycol (PEG)-N-hydroxysuccinimide (NHS) for treatment and evaluated in vivo biocompatibility. The New Zealand White rabbits (N = 20) were randomly grouped into the keratectomy-only and keratectomy with PEG-collagen hydrogel-treated groups. Samples were processed for immunohistochemical evaluation. In both clinical and histologic observations, epithelial cells were able to migrate and form multilayers over the PEG-collagen hydrogels at the site of the corneal stromal defect. There was no evidence of inflammatory or immunological reactions or increased IOP for PEG-collagen hydrogel-treated corneas during the four weeks of observation. Immunohistochemistry revealed the presence of α-smooth muscle actin (α-SMA) in the superior corneal stroma of the keratectomy-only group (indicative of fibrotic healing), whereas low stromal α-SMA expression was detected in the keratectomy with PEG-collagen hydrogel-treated group. Taken together, we suggest that PEG-collagen may be used as a safe and effective alternative in treating corneal defect in clinical setting.

Kim M, et al. Korean J Ophthalmol. 2017 Feb;31(1):25-31. https://doi.org/10.3341/kjo.2017.31.1.25