Clinical Features and Visual Outcome of Infectious Keratitis Associated with Orthokeratology Lens in Korean Pediatric Patients.

Purpose: To investigate the clinical features and visual outcome of infectious keratitis associated with Orthokeratology (Ortho-K) lens in Korean pediatric patients. Methods: We retrospectively reviewed medical records of patients diagnosed with Ortho-K lens-associated infectious keratitis from June 2005 to April 2020 at a tertiary referral hospital. Patients' demographics, clinical features, microbiological evaluation, and treatment methods were assessed and factors related to final visual outcomes were analyzed. Results: The study included 26 eyes of 26 patients (19 female, 7 male; mean age: 11.9 years), with an average Ortho-K lens wear duration of 33.7 ± 21.2 months. The highest number of cases occurred in summer (42.3%, 11/26). Central or paracentral corneal lesions were observed in 96.2% (25/26) of cases, with a mean corneal epithelial defect size of 5.13 mm². Pseudomonas aeruginosa was the most commonly isolated organism (n = 5), followed by Serratia marcescens (n = 4). All patients responded to medical treatment without needing surgical intervention. 72% of cases achieved favorable visual outcomes (Snellen BCVA > 6/12), while 8% experienced severe visual impairment (Snellen BCVA ≤ 6/60) due to residual central corneal opacities. Multivariable analysis showed that non-summer seasons, duration from symptom onset to presentation, and corneal epithelial defect size were significantly associated with final logMAR BCVA (p = 0.043, p = 0.040, and p = 0.002, respectively). Failed autorefraction at presentation due to an Ortho-K-related infectious keratitis lesion was a significant predictor of poor final visual outcome (Snellen BCVA ≤ 6/12) (OR = 38.995, p = 0.030). Conclusions: Ortho-K lens-related infectious keratitis can lead to permanent corneal opacities and potentially devastating visual outcomes in children. Delayed time to presentation, large corneal lesions, failure of autorefraction, and non-summer seasons were associated with poorer outcomes. Proper education and early detection would be key to safe use of orthokeratology lenses in pediatric patients.

Adverse effects of meteorological factors and air pollutants on dry eye disease: a hospital-based retrospective cohort study.

Although previous studies have suggested that meteorological factors and air pollutants can cause dry eye disease (DED), few clinical cohort studies have determined the individual and combined effects of these factors on DED. We investigated the effects of meteorological factors (humidity and temperature) and air pollutants [particles with a diameter ≤ 2.5 µ m (PM2.5), ozone (O3), nitrogen dioxide (NO2), and carbon monoxide (CO)] on DED. A retrospective cohort study was conducted on 53 DED patients. DED was evaluated by Symptom Assessment in Dry Eye (SANDE), tear secretion, tear film break-up time (TBUT), ocular staining score (OSS), and tear osmolarity. To explore the individual, non-linear, and joint associations between meteorological factors, air pollutants, and DED parameters, we used generalized linear mixed model (GLMM) and Bayesian kernel machine regression (BKMR). After adjusting for all covariates, lower relative humidity or temperature was associated with a higher SANDE (p < 0.05). Higher PM2.5, O3, and NO2 levels were associated with higher SANDE and tear osmolarity (p < 0.05). Higher O3 levels were associated with lower tear secretion and TBUT, whereas higher NO2 levels were associated with higher OSS (p < 0.05). BKMR analyses indicated that a mixture of meteorological factors and air pollutants was significantly associated with increased SANDE, OSS, tear osmolarity, and decreased tear secretion.

Recent warming and increasing CO2 stimulate growth of dominant trees under no water limitation in South Korea.

Increases of temperatures and atmospheric CO2 concentration influence the growth performance of trees worldwide. The direction and intensity of tree growth and physiological responses to changing climate do, however, vary according to environmental conditions. Here we present complex, long-term, tree-physiological responses to unprecedented temperature increase in East Asia. For this purpose, we studied radial growth and isotopic (δ13C and δ18O) variations using tree-ring data for the past 100 years of dominant Quercus mongolica trees from the cool-temperate forests from Hallasan, South Korea. Overall, we found that tree stem basal area increment, intercellular CO2 concentration, and intrinsic water-use efficiency significantly increased over the last century. We observed, however, short-term variability in the trends of these variables among four periods identified by change point analysis. In comparison, δ18O did not show significant changes over time, suggesting no major hydrological changes in this precipitation-rich area. The strength and direction of growth-climate relationships also varied during the past 100 years. Basal Area Increment (BAI) did not show significant relationships with the climate over 1924-1949 and 1975-1999 periods. However, over 1950-1974 BAI was negatively affected by both temperature and precipitation, while after 2000 a temperature stimulus was observed. Finally, over the last two decades, the increase in Q. mongolica tree growth accelerated and was associated with high spring-summer temperatures and atmospheric CO2 concentrations and decreasing intrinsic water-use efficiency, δ18O, and VPD, suggesting that the photosynthetic rate continued increasing under no water limitations. Our results indicate that the performance of dominant trees of one of the most widely distributed species in East Asia has benefited from recent global changes, mainly over the last two decades. Such findings are essential for projections of forest dynamics and carbon sequestration under climate change.

Re-Esterified Triglyceride ω-3 Fatty Acids in Dry Eye Disease With Meibomian Gland Dysfunction: A Randomized Clinical Trial.

Importance: Taking ω-3 supplements has been associated with a reduction in symptoms of dry eye disease (DED) associated with meibomian gland dysfunction (MGD). However, a recent relatively large clinical trial concluded that treating DED with ω-3 consumption was ineffective, potentially warranting additional investigations. Objectives: To investigate the effect of re-esterified triglyceride (rTG) ω-3 fatty acid supplementation on DED associated with MGD. Design, Setting, and Participants: This double-masked, parallel-group, randomized clinical trial was conducted at 7 institutions from September 2020 to January 2023. Patients with DED associated with MGD were included and randomly assigned to the ω-3 group (received 1680 mg of eicosapentaenoic acid and 560 mg of docosahexaenoic acid), whereas those in the grape-seed group received 3000 mg of grape-seed oil daily. Interventions: rTG ω-3 Fatty acid supplementation vs grape-seed oil. Main Outcome Measures: The primary end point was the Ocular Surface Disease Index (OSDI) from baseline to 6 and 12 weeks. The safety parameters were visual acuity and intraocular pressure change. Results: A total of 132 patients (mean [SD] age, 50.6 [13.8] years; 103 female [78.0%]) were included in this study. The mean (SD) baseline OSDI scores of the ω-3 and grape-seed groups were 43.5 (16.5) and 44.1 (16.6), respectively. A total of 58 patients (87.9%) and 57 patients (86.4%) in the ω-3 and grape-seed groups, respectively, completed 12 weeks of follow-up. There were no differences in compliance with the dietary supplement intake between groups (ω-3, 95.8% and grape-seed, 95.4%). The OSDI (SD) change from baseline to 6 and 12 weeks was -20.5 (16.0) and -22.7 (15.7), respectively, in the ω-3 group and -15.1 (20.2) and -18.8 (21.7), respectively, in the grape-seed control group (difference at 6 weeks = -5.4; 95% CI, -12.15 to 1.33; P = .12 and at 12 weeks = -3.9; 95% CI, -10.90 to 3.13; P = .28). There were no changes in safety parameters or adverse events related to taking the dietary supplement in either group. Conclusions and Relevance: This randomized clinical trial did not show a benefit of the rTG form of ω-3 for ameliorating symptoms of DED associated with MGD, although fewer than 60 participants were evaluated in each group. Any secondary outcomes from this study should be considered for hypothesis generation of future evaluations of the effect of the rTG form of ω-3 on DED associated with MGD. Trial Registration: CRIS Identifier: KCT0004927.

Visual Outcomes According to Age After Bilateral Implantation of Trifocal Intraocular Lenses.

PURPOSE: To investigate the effect of age on visual outcomes after the bilateral implantation of trifocal intraocular lenses (IOLs). METHODS: A total of 290 patients (580 eyes) who underwent bilateral implantation of a trifocal IOL were enrolled in this retrospective case-control study. Patients were divided into five age groups: 45 to 49, 50 to 54, 55 to 59, 60 to 64, and 65 years and older. Postoperative monocular uncorrected and corrected distance visual acuity (UDVA and CDVA, respectively), uncorrected near visual acuity (UNVA), binocular distance-corrected defocus curve, spectacle dependence for near and distance vision, and patient satisfaction scores were compared among the five groups. RESULTS: The 45 to 49 years group had significantly better mean UDVA (0.02 ± 0.05 logMAR) and UNVA (0.02 ± 0.04 logMAR) than the 65 years and older group (0.06 ± 0.09 and 0.09 ± 0.09 logMAR; P = .029 and P < .001; respectively). However, no significant differences were observed in the mean CDVA among the groups. Binocular visual performance of the 45 to 49 years group was better than that of the 65 years and older age group at defocuses of +1.00, +0.50, -1.00, and -3.00 D. No significant differences were observed in spectacle dependence for near and distance vision or in patient satisfaction scores among the five groups. CONCLUSIONS: Bilateral implantation of trifocal IOLs can provide excellent near and distance vision in both young and older patients. However, UDVA and UNVA revealed considerably worse results in the older group, although no significant difference was observed in CDVA and postoperative refractive errors by age. [J Refract Surg. 2024;40(4):e270-e277.].

New Korean Guidelines for the Diagnosis and Management of Dry Eye Disease.

New Korean guidelines for the diagnosis and management of dry eye disease were developed based on literature reviews by the Korean Dry Eye Guideline Establishment Committee, a previous dry eye guideline by Korean Corneal Disease Study Group, a survey of Korean Dry Eye Society (KDES) members, and KDES consensus meetings. The new definition of dry eye was also proposed by KDES regular members. The new definition by the regular members of the KDES is as follows: "Dry eye is a disease of the ocular surface characterized by tear film abnormalities and ocular symptoms." The combination of ocular symptoms and an unstable tear film (tear breakup time <7 seconds) was considered as essential components for the diagnosis of dry eye. Schirmer test and ocular surface staining were considered adjunctive diagnostic criteria. The treatment guidelines consisted of a simplified stepwise approach according to aqueous deficiency dominant, evaporation dominant, and altered tear distribution subtypes. New Korean guidelines can be used as a simple, valid, and accessible tool for the diagnosis and management of dry eye disease in clinical practice.

Modified intraocular lens power selection method according to biometric subgroups Eom IOL power calculator.

This study evaluates the accuracy of a newly developed intraocular lens (IOL) power calculation method that applies four different IOL power calculation formulas according to 768 biometric subgroups based on keratometry, anterior chamber depth, and axial length. This retrospective cross-sectional study was conducted in at Korea University Ansan Hospital. A total of 1600 eyes from 1600 patients who underwent phacoemulsification and a ZCB00 IOL in-the-bag implantation were divided into two datasets: a reference dataset (1200 eyes) and a validation dataset (400 eyes). Using the reference dataset and the results of previous studies, the Eom IOL power calculator was developed using 768 biometric subgroups. The median absolute errors (MedAEs) and IOL Formula Performance Indexes (FPIs) of the Barrett Universal II, Haigis, Hoffer Q, Holladay 1, Ladas Super, SRK/T, and Eom formulas using the 400-eye validation dataset were compared. The MedAE of the Eom formula (0.22 D) was significantly smaller than that of the other four formulas, except for the Barrett Universal II and Ladas Super formulas (0.24 D and 0.23 D, respectively). The IOL FPI of the Eom formula was 0.553, which ranked first, followed by the Ladas Super (0.474), Barrett Universal II (0.470), Holladay 1 (0.444), Hoffer Q (0.396), Haigis (0.392), and SRK/T (0.361) formulas. In conclusion, the Eom IOL power calculator developed in this study demonstrated similar or slightly better accuracy than the Barrett Universal II and Ladas Super formulas and was superior to the four traditional IOL power calculation formulas.

Effects of particulate matter exposure on the expression of the SARS-CoV-2 ACE2 receptor in ocular surface tissues and cells.

Particulate matter (PM) has been reported to be one of the risk factor for COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, although the ocular surface is deeply affected by both PM exposure and SARS-COV-2 infection, no studies have investigated the effects of PM exposure on the ocular route of SARS-COV-2 infection. To this end, we explored the effects of PM on the expression of SARS-COV-2-associated receptors and proteins in ocular surface. Herein, short- and long-term PM-exposed rat models were established by topically administering PM for 3 and 10 days, respectively. Immortalized human corneal epithelial cells (HCECs) and human conjunctival epithelial cells (HCjECs) were exposed to PM. ACE2, TMPRSS2, CD147, and ADAM17 expression levels were measured by western blot analysis. Our results show that short-term PM exposure had little effect on the expressions of ACE2, TMPRSS2, and CD147 in ocular surface tissues. However, long-term PM exposure decreased the ACE2 expression in conjunctival tissues and increased the CD147 expression in corneal or conjunctival tissues. PM exposure reduced the ACE2 expression by increasing the ADAM17 expression and ACE2 shedding level in HCECs and HCjECs. Our findings suggest that long-term PM exposure down-regulate the expression of the SARS-CoV-2 receptor ACE2 in conjunctival tissues through ADAM17-dependent ACE2 shedding. However, long-term PM exposure up-regulates the expression of another SARS-CoV-2 receptor CD147 in ocular surface tissues, accompanied by ocular surface damage and cytotoxicity. This study provides a new insight into uncovering potential risk factors for infection with SARS-CoV-2 via the ocular route.