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Purpose: To describe current cataract surgery practice patterns and trends among Korean ophthalmologists., Methods: A survey was conducted among members of the Korean Society of Cataract and Refractive Surgery in October 2020. Of the 998 questionnaires, 262 (26.3%) were received for analysis. Data were analyzed using descriptive statistics and compared with those of previous surveys., Results: The largest percentage of respondents (39%) had <5 years of practical experience, and 40% had >11 years of practical experience. The average, median, and mode monthly volumes of cataract surgeries performed by the Korean Society of Cataract and Refractive Surgery members were 31, 20, and 10 cases, respectively. Topical anesthesia was administered by 85% of the respondents. For intraocular lens (IOL) calculations, 96% of the respondents used optical biometry. The proportion of surgeons providing femtosecond laser-assisted cataract surgery increased significantly from 5% in 2018 to 29% in 2020. This increase was accompanied by an increase in the multifocal IOLs. Those who implant multifocal IOL for >10% of their cases increased from 16% (2018) to 29% (2020). Topical nonsteroidal anti-inflammatory drugs were prescribed postoperatively by 76% of the respondents. Most respondents (70%) prescribed these anti-inflammatory drugs for 4 weeks., Conclusions: This survey provided a comprehensive update on current cataract surgery practice in the Republic of Korea. The results highlighted the increasing use of premium IOLs, femtosecond laser-assisted cataract surgery, optical biometry, and topical anesthesia to better meet the patients' needs.

This nationwide population-based study investigated the incidence rate of and risk factors for the progression to corneal transplantation in patients with keratoconus in South Korea using claims data from the Health Insurance Review and Assessment service. Among the entire South Korean population, 10,612 patients newly diagnosed with keratoconus between January 2010 and June 2015 were identified and included in the study. During the study period, 124 patients (1.17%) underwent corneal transplantation, with an average follow-up period of 2.97 ± 1.59 years. The incidence rate of corneal transplantation in patients with keratoconus was 4.46 cases per 1000 person-years. The rate of corneal transplantation for keratoconus was relatively low in South Korea compared to other countries. Multivariate Cox regression analysis revealed that male sex (HR 2.37; 95% CI 1.61-3.50; P < 0.001), severe atopic dermatitis (HR 2.32; 95% CI 1.02-5.28; P = 0.044), obstructive sleep apnea (HR 9.78; 95% CI 1.36-70.10; P = 0.023), and intellectual disability (HR 4.48; 95% CI 1.33-15.11; P = 0.016) significantly increased the risk of progression to corneal transplantation. In patients with keratoconus, male sex, severe atopic dermatitis, obstructive sleep apnea, and intellectual disability were associated with an increased risk of corneal transplantation.

Purpose: To investigate the impact of the metabolic syndrome (METS) on the incidence of retinal vein occlusion (RVO)., Methods: This is a retrospective cohort study using Korean National Health Insurance System data. 23,153,600 subjects without previous history of RVO underwent a National Health Screening Program examination between 2009 and 2012. They were monitored for RVO development (registration of diagnostic code for RVO) until 2015. Presence of METS was defined using the data from the National Health Screening Program examination according to the revised criteria of the National Cholesterol Education Program Adult Treatment Panel III. A multivariate adjusted Cox regression analysis was used to reveal hazard ratios and 95% confidence interval for RVO development in the presence of METS., Results: The age of the subjects was 47.64 ± 13.51 years. In this cohort, 11,747,439 (50.7%) were male, 11,406,161 (49.3%) were female, and 6,398,071 subjects (27.6%) were diagnosed with METS. The overall incidence of RVO was 0.947 per 1000 person-years. The adjusted hazard ratio of RVO in the presence of METS was 1.458 (95% confidence interval, 1.440-1.475; P < 0.001) after adjusting for age, sex, smoking status, alcohol consumption, physical activity, and income. Among all of the criteria for METS diagnosis, elevated blood pressure was the greatest risk for RVO development (adjusted hazard ratio, 1.610; 95% confidence interval, 1.589-1.631; P < 0.001)., Conclusions: METS and each of diagnostic criteria was associated with an increased risk of RVO development. Elevated blood pressure seems to be especially important factors for RVO development., Translational Relevance: Our results provide information about the link between METS and RVO., Competing Interests: Disclosure: D.H. Lim, None; K.Y. Shin, None; K. Han, None; S.W. Kang, None; D.-I. Ham, None; S.J. Kim, None; Y.G. Park, None; T.-Y. Chung, None, (Copyright 2020 The Authors.)

Background: To investigate the 3-month postoperative performance and safety after implantation of a trifocal intraocular lens (IOL) in a Korean population., Methods: This was a clinical, prospective, multicenter, single-arm study. Forty-four subjects (88 eyes) with bilateral cataract with expected postoperative corneal astigmatism of < 1.00 diopter (D) and no ocular disease or eye condition underwent bilateral implantation of the AcrySof IQ® PanOptix IOL (TFNT00). Postoperative examination at 3 months included binocular defocus curve; binocular best corrected distance visual acuity (BCDVA); monocular/binocular uncorrected VA (UCVA) at distance (4 m), intermediate (60 cm), and near (40 cm); contrast sensitivity under photopic conditions with/without glare; and subjective outcomes, including satisfaction and spectacle independence., Results: Binocular defocus curve at 3 months after bilateral implantation showed VA of 0.1 logMAR or better from + 0.5 D through - 2.5 D. Binocular BCDVA mean ± SD at 4 m was - 0.05 ± 0.07 logMAR. Binocular and monocular UCVA was 0.03 ± 0.1 and 0.08 ± 0.12 logMAR (4 m), - 0.00 ± 0.11 and 0.05 ± 0.13 logMAR (60 cm), and 0.03 ± 0.12 and 0.09 ± 0.13 logMAR (40 cm), respectively. Contrast sensitivity with glare was 1.67 ± 0.13, 1.91 ± 0.17, 1.54 ± 0.21, and 1.14 ± 0.20 log units at 3, 6, 12, and 18 cycles/degree, respectively. At near and intermediate distances, 84 and 77% of subjects reported good/excellent satisfaction, and 84 and 91% of subjects reported spectacle independence, respectively., Conclusions: In a Korean population, visual performance of the trifocal TFNT00 IOL 3 months postoperatively was < 0.1 logMAR for binocular UCVA at all distances, with high subject satisfaction and spectacle independence., Trial Registration: www.ClinicalTrials.gov ( NCT03268746 ). Registered August 31, 2017.

Purpose: Few studies have measured the incidence and risk factors of intraocular lens (IOL) dislocation in the total population. We investigate the risk factors for IOL dislocation in a nationwide Korean cohort., Design: Retrospective cohort study., Methods: National data on 2,162,191 subjects who underwent cataract surgery were collected from the Health Insurance Review and Assessment service database of health claims from 2009 to 2016. The Health Insurance Review and Assessment database was used to identify potential risk factors for IOL dislocation, including age, sex, and various pre- and postoperative ophthalmic conditions. The hazard ratios (HRs) and confidence intervals (CIs) of these risk factors were assessed with a multivariable-adjusted Cox regression model., Results: IOL dislocation occurred in 15,170 patients (0.7%) in the cataract surgery cohort (2,162,191 patients). The incidence rate of IOL dislocation peaked at 40-50 years of age, although the mean age of IOL dislocation was 65.25 ± 10.81 years. The average male:female ratio was 1.8. The adjusted HR for IOL dislocation in patients with partial vitrectomy was 11.93 (95% CI 10.95-12.99; P < .0001). Posterior capsulotomy performed within 1 year after the cataract surgery significantly decreased IOL dislocation, with an adjusted HR of 0.48 (95% CI 0.44-0.51; P < .0001)., Conclusions: IOL dislocation tended to occur in young males. Anterior vitrectomy was a significant risk factor for IOL dislocation, while posterior capsulotomy after surgery was associated with a decreased risk of IOL dislocation., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: To compare the outcomes of myopia and myopic astigmatism corrected with topography-modified refraction laser in situ keratomileusis (TMR-LASIK), wavefront-optimized (WFO) LASIK, and topography-guided (TG) LASIK with a correction target based on the manifest refraction (manifest TG-LASIK)., Methods: This observational, retrospective cohort study included patients who underwent LASIK using the WaveLight® EX500 excimer laser to correct myopia and myopic astigmatism between August 2016 and July 2017. Patients who underwent TMR-LASIK (85 patients), WFO-LASIK (70 patients), or manifest TG-LASIK (40 patients) were enrolled, and only one eye from each patient was analyzed. All participants underwent measurement of the uncorrected distance visual acuity (UDVA), best-corrected distance visual acuity (BCVA), manifest refraction, vector analysis of astigmatic change, corneal topography, and corneal wavefront analysis at baseline and at every posttreatment visit., Results: Three months postoperatively, a UDVA of 0.0 logMAR or better and manifest refraction spherical equivalent (MRSE) within ±0.5 diopters (D) did not differ across the TMR-, WFO-, and manifest TG-LASIK groups. However, the residual cylinder in the TMR group was significantly larger than that in the WFO and manifest TG groups. The magnitude of error in the TMR group measured using astigmatism vector analysis was significantly higher than that in the WFO and manifest TG groups., Conclusions: Although these three LASIK platforms achieved the predicted surgical outcomes, TMR-LASIK overcorrected astigmatism and showed a higher residual postoperative astigmatism compared with WFO- and manifest TG-LASIK.

Background: Accurately predicting refractive error in children is crucial for detecting amblyopia, which can lead to permanent visual impairment, but is potentially curable if detected early. Various tools have been adopted to more easily screen a large number of patients for amblyopia risk., Objective: For efficient screening, easy access to screening tools and an accurate prediction algorithm are the most important factors. In this study, we developed an automated deep learning-based system to predict the range of refractive error in children (mean age 4.32 years, SD 1.87 years) using 305 eccentric photorefraction images captured with a smartphone., Methods: Photorefraction images were divided into seven classes according to their spherical values as measured by cycloplegic refraction., Results: The trained deep learning model had an overall accuracy of 81.6%, with the following accuracies for each refractive error class: 80.0% for ≤-5.0 diopters (D), 77.8% for >-5.0 D and ≤-3.0 D, 82.0% for >-3.0 D and ≤-0.5 D, 83.3% for >-0.5 D and <+0.5 D, 82.8% for ≥+0.5 D and <+3.0 D, 79.3% for ≥+3.0 D and <+5.0 D, and 75.0% for ≥+5.0 D. These results indicate that our deep learning-based system performed sufficiently accurately., Conclusions: This study demonstrated the potential of precise smartphone-based prediction systems for refractive error using deep learning and further yielded a robust collection of pediatric photorefraction images., (©Jaehyeong Chun, Youngjun Kim, Kyoung Yoon Shin, Sun Hyup Han, Sei Yeul Oh, Tae-Young Chung, Kyung-Ah Park, Dong Hui Lim. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 05.05.2020.)

Purpose: Human corneal endothelial cells (hCECs) have limited regenerative capacity in vivo. Reduced hCEC density results in bullous keratopathy requiring corneal transplantation. This study reveals the role of transcription factor 4 (TCF4) in hCEC diseases and suggests that TCF4 may be a molecular target for hCEC regeneration., Methods: Cell shape, cell proliferation rates, and proliferation-associated proteins were evaluated in normal or senescent hCECs. TCF4 was blocked by siRNA (si-TCF4) or activated using clustered regularly interspaced short palindromic repeats (CRISPR)/dCas9 activation systems (pl-TCF4). The corneal endothelium of six-week-old Sprague-Dawley (SD) rats was transfected by electroporation followed by cryoinjury., Results: Cell proliferation rates and TCF4 levels were reduced in senescent cells. TCF4 CRISPR activation enhanced corneal endothelial wound healing. TCF4 regulated mitochondrial functions including mitochondrial membrane potential, mitochondrial superoxide levels, and energy production. The percentage of cells in the S-phase was reduced with si-TCF4 and increased with pl-TCF4. Cell proliferation and cell cycle-associated proteins were regulated by TCF4. Autophagy was induced by si-TCF4. In vivo transfection of CRISPR/dCas9 activation systems (a-TCF4) induced regeneration of corneal endothelium., Conclusions: Corneal endothelial diseases are associated with TCF4 reduction; TCF4 may be a potential target for hCEC diseases. Gene therapy using TCF4 CRISPR/dCas9 may be an effective treatment for hCEC diseases.

Background: We sought to describe corneal epithelial changes after using epidermal (EGFR) or fibroblast growth factor receptor (FGFR) inhibitors as chemotherapy and to clarify incidence and prognosis., Materials: Retrospective chart review., Results: Among 6871 patients and 17 EGFR or FGFR inhibitors, 1161 patients (16.9%) referred for ophthalmologic examination. In total, 1145 patients had disease-related or unrelated ocular complications. Among 16 patients with treatment-related ocular complications, three patients had treatment-related radiation retinopathy and one patient showed treatment-related corneal ulcer. Finally the authors identified that, in 12 patients, three EGFR inhibitors and two FGFR inhibitors caused corneal epithelial lesions. Vandetanib, Osimertinib, and ABT-414 caused vortex keratopathy in nine patients, while ASP-5878 and FPA-144 caused epithelial changes resembling corneal dysmaturation in three patients. The mean interval until symptoms appeared was 246 days with vandetanib, 196 days with osimertinib, 30 days with ABT-414, 55 days with ASP-5878, and 70 days with FPA-144. The mean of the lowest logarithm of minimal angle of resolution visual acuity results of the right and left eyes after chemotherapy were 0.338 and 0.413. The incidence rates of epithelial changes were 15.79% with vandetanib, 0.5% with osimertinib, 100% with ABT-414, 50.0% with ASP-5878, and 18.2% with FPA-144. After excluding deceased patients and those who were lost to follow-up or still undergoing treatment, we confirmed the reversibility of corneal lesions after the discontinuation of each agent. Seven patients showed full recovery of their vision and corneal epithelium, while three achieved a partial level of recovery. Although patients diagnosed with glioblastoma used prophylactic topical steroids before and during ABT-414 therapy, all developed vortex keratopathy., Conclusions: EGFR and FGFR inhibitors are chemotherapy agents that could make corneal epithelial changes. Contrary to the low probability of ocular complication with old EGFR drugs, recently introduced EGFR and FGFR agents showed a high incidence of ocular complication with severe vision distortion. Doctors should forewarn patients planning chemotherapy with these agents that decreased visual acuity could develop due to corneal epithelial changes and also reassure them that the condition could be improved after the end of treatment without the use of steroid eye drops., Trial Registration: This study was approved by the institutional review board (IRB) of Samsung Medical Center (IRB no. 2019-04-027) and was conducted according to the principles expressed in the Declaration of Helsinki.

Purpose: We sought to evaluate the distribution and characteristics of meibomian gland dysfunction (MGD) and the treatment patterns for symptomatic MGD patients in South Korea., Methods: One hundred ninety-six right eyes of 196 MGD patients were enrolled. For each patient, meibum expressibility in the central eight glands in both the upper and lower eyelids was examined. Each upper and lower eyelid was separately classified into one of the following three subtypes: nonobvious obstructive (low-delivery without lid margin abnormality), obvious obstructive (low-delivery with lid margin abnormality), and hypersecretory (high-delivery with lid margin abnormality). All treatment plans were also recorded., Results: The mean number of expressible glands of the central eight glands in the upper eyelids (3.9 ± 2.6) was significantly higher than that in the lower eyelids (2.2 ± 2.4, p < 0.001). Obvious obstructive MGD was the most common subtype, followed by the hypersecretory and nonobvious obstructive subtypes in both the upper and lower eyelids. Of the 196 subjects, 38 (19.4%) had upper and lower eyelids that were assigned to different categories. Eyelid hygiene was the most prescribed treatment (74.5%), followed by lubricant eye drop usage (71.5%). Physicians tended to determine treatment plans based on the subtype of the upper eyelid rather than that of the lower eyelid., Conclusions: The majority of subjects were classified as having the obvious obstructive subtype of MGD, and 19.4% had upper and lower eyelids that were different subtypes. Eyelid hygiene was the most prescribed treatment for MGD patients, and treatment patterns were mostly determined based on the subtype of the upper eyelids., Competing Interests: No potential conflict of interest relevant to this article was reported., (© 2019 The Korean Ophthalmological Society.)

Objectives: To investigate the topographic factors related to axial length (AL) growth rate in orthokeratology., Methods: Clinical data of myopic children with orthokeratology lenses from 2010 to 2016 were investigated. Corneal topography (Orbscan II) and IOLMaster-measured AL at baseline and every posttreatment visit were analyzed. Optical map topographies from baseline- and posttreatment-stabilized corneas were analyzed to calculate the refractive power difference between the apex and the periphery (apex-periphery refractive power difference [ARPD]), which estimates the change of peripheral refraction. A generalized estimating equation (GEE) was used to assess the associations between AL growth and topographic changes in both eyes., Results: The mean baseline spherical equivalent (SE) was -2.40±1.12 diopters (D) and the mean AL was 24.38±0.77 mm. Over a mean follow-up period of 41.9 months, the mean AL growth rate was 0.22±0.15 mm/year. In a univariable GEE analysis, age at initial lens wear, baseline AL, baseline SE, central corneal thickness (CCT), baseline apex power, and posttreatment ARPD on optical topography maps were all significantly correlated with AL growth rate (P<0.001, 0.009, 0.024, 0.011, 0.010, and 0.006, respectively). In a multivariable GEE, CCT and posttreatment ARPD were identified as significant factors (P=0.014 and 0.016, respectively)., Conclusions: The AL growth rate was significantly associated with CCT and posttreatment relative peripheral refractive power, in addition to age at initial lens wear. These associations might possibly demonstrate an effect of treatment-induced peripheral refraction changes on retardation of myopic progression, whereas younger age might significantly influence both AL growth rate and corneal deformation.

Introduction and Objectives: The aim of this study was to evaluate the effect of aliskiren on aortic stiffness in patients with Marfan syndrome (MS)., Methods: Twenty-eight MS patients (mean age ± standard deviation: 32.6 ± 10.6 years) were recruited from November 2009 to October 2014. All patients were receiving atenolol as standard beta-blocker therapy. A prospective randomization process was performed to assign participants to either aliskiren treatment (150-300mg orally per day) or no aliskiren treatment (negative control) in an open-label design. Central aortic distensibility and central pulsed wave velocity (PWV) by magnetic resonance imaging (MRI), peripheral PWV, central aortic blood pressure and augmentation index by peripheral tonometry, and aortic dilatation by echocardiography were examined initially and after 24 weeks. The primary endpoint was central aortic distensibility by MRI., Results: In analyses of differences between baseline and 24 weeks for the aliskiren treatment group vs the negative control group, central distensibility (overall; P = .26) and central PWV (0.2 ± 0.9 vs 0.03 ± 0.7 [m/s]; P = .79) by MRI were not significantly different. Central systolic aortic blood pressure tended to be lower by 14mmHg in patients in the aliskiren treatment group than in the control group (P = .09). A significant decrease in peripheral PWV (brachial-ankle PWV) in the aliskiren treatment group (-1.6 m/s) compared with the control group (+0.28 m/s) was noted (P = .005)., Conclusions: Among patients with MS, the addition of aliskiren to beta-blocker treatment did not significantly improve central aortic stiffness during a 24-week period., (Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.)

Purpose: To determine deep optic nerve head structure changes after transient intraocular pressure elevation during laser in situ keratomileusis (LASIK) for myopia., Methods: Enhanced depth imaging-optical coherence tomography was performed in each myopic eye that underwent LASIK surgery. Enhanced depth imaging-optical coherence tomography images were created at postoperative 1 day, 1 week, 2 weeks, and 1 month. Lamina cribrosa (LC) thickness, LC depth and prelaminar thickness at the superior, middle and inferior portions of the optic nerve head were measured by two investigators., Results: Forty eyes in 40 patients were included in the present study. During follow-up, there were no significant differences in prelaminar thickness or LC depth. The LC demonstrated increased thickness at postoperative 1 day at all three locations (superior, middle, and inferior) (p < 0.001, p < 0.001, p < 0.001, respectively). However, no significant changes were observed at postoperative 1 week, 2 weeks, and 1 month., Conclusions: The LC thickness could increase at 1 day after LASIK surgery. However, the thickness will gradually return to baseline morphology. Temporary intraocular pressure increase during LASIK does not appear to induce irreversible LC thickness changes., Competing Interests: No potential conflict of interest relevant to this article was reported., (© 2018 The Korean Ophthalmological Society.)

Aim: To assess visual quality after presbyopia correction using an aspheric ablation profile and a micro-monovision protocol., Methods: This is a retrospective interventional study. Fifty-four eyes of 27 patients (mean age, 50.2±7.5y) who underwent presbyopia correction with an aspheric micro-monovision protocol were enrolled. The values of modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI) and accommodation range were quantitatively assessed using the HD analyzer. Preoperative and postoperative contrast sensitivity (CS) at far (2.5 m) and near (40 cm) distance and higher-order aberrations (HOAs) were analyzed. Subjective visual satisfaction was evaluated by self-reported questionnaire regarding optical visual symptoms., Results: One year after presbyopia correction, no significant differences were found in the MTF cutoff frequency, Strehl ratio and OSI, however, the HD analyzer accommodation range significantly differed postoperatively ( P =0.004). Postoperative CS at 12 and 18 cpd at near showed statistically significant improvement ( P =0.020 and 0.008, respectively). Visual performance by self-reported questionnaire revealed satisfactory results in terms of subjective visual quality improvement., Conclusion: Objective optical quality parameters show good visual outcomes. Subjective visual quality assessed by self-reported questionnaire in the presbyopia correction group show satisfactory results.

Purpose: To evaluate macular photostress and visual experience between coaxial microscope illumination versus oblique intracameral illumination during cataract surgery., Setting: Gachon University Gil Hospital, Incheon, South Korea., Design: Prospective case series., Methods: Consecutive patients who had cataract surgery using microscope illumination and intracameral illumination were included. The patients were asked to complete a questionnaire (seeing strong lights, feeling photophobia, feeling startled (fright) when seeing lights, seeing any colors, seeing any instruments or surgical procedures, and estimating intraoperative visual function) designed to describe their cataract surgery experience. The images projected on the retina of the model eye (rear view) with artificial opaque fragments in the anterior chamber during simulating cataract surgery were compared between the 2 illumination types., Results: Sixty patients completed the questionnaire. Scores for strong lights, photophobia, fright, and color perception were significantly higher with microscope illumination than with intracameral illumination (all P < .001). More patients preferred the intracameral illumination (45 [75.0%]) to the microscope illumination (13 [21.7%]). In the rear-view images created in a model eye, only the bright microscope light in the center was seen without any lens image in the microscope illumination. However, in the intracameral illumination, the less bright light from the light pipe in the periphery and the lens fragments were seen more clearly., Conclusions: In a view of the patients' visual experience, oblique intracameral illumination caused less subjective photostress and was preferred over coaxial microscope illumination. Objective findings from the model-eye experiment correlated to the result of visual experience., (Copyright © 2018 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Aim: The aim of this study is to investigate the factors affecting tear film and ocular surface in patients with facial burns., Methods: A total of 273 patients with facial burns, treated at Hallym University Hangang Sacred Heart Hospital from November 2012 to July 2015, were included. Tear break-up time (TBUT), Schirmer's tear secretion test, fluorescein staining score (FSS), ocular surface disease index (OSDI), and visual analogue pain score (VAS) were compared according to burned surface area, burn site, burn cause, time since burn injury, or lid abnormality., Results: Mean age was 48.66±14.46years (range: 18-85). Tear film stability was not different according to burn area, burn site, or burn cause. Facial burn patients with lid abnormalities had shorter TBUT and higher OSDI scores compared to no lid abnormality (p<0.001 and 0.015, independent t-test). There was no difference in TBUT and tear secretion according to area, site, or cause of burn. FSS was different according to the area of burn (p=0.007, ANOVA). OSDI and VAS was higher in the patients with an electrical burn compared to thermal burn (p=0.003 and 0.024, ANOVA)., Conclusions: Facial burn patients with lid abnormalities had tear film instability and ocular discomforts. Aggressive treatment may be of benefit in facial burn patients with lid involvement. Electrical burn caused more severe pain compared to thermal burn. Attention should be paid to pain control in patients with electrical burns., (Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.)

Primary open-angle glaucoma (POAG) is often caused by elevated intraocular pressure (IOP), which arises due to increased resistance to aqueous humor outflow (AHO). Aqueous humor flows through Schlemm's canal (SC), a lymphatic-like vessel encircling the cornea, and via intercellular spaces of ciliary muscle cells. However, the mechanisms underlying increased AHO resistance are poorly understood. Here, we demonstrate that signaling between angiopoietin (Angpt) and the Angpt receptor Tie2, which is critical for SC formation, is also indispensable for maintaining SC integrity during adulthood. Deletion of Angpt1/Angpt2 or Tie2 in adult mice severely impaired SC integrity and transcytosis, leading to elevated IOP, retinal neuron damage, and impairment of retinal ganglion cell function, all hallmarks of POAG in humans. We found that SC integrity is maintained by interconnected and coordinated functions of Angpt-Tie2 signaling, AHO, and Prox1 activity. These functions diminish in the SC during aging, leading to impaired integrity and transcytosis. Intriguingly, Tie2 reactivation using a Tie2 agonistic antibody rescued the POAG phenotype in Angpt1/Angpt2-deficient mice and rejuvenated the SC in aged mice. These results indicate that the Angpt-Tie2 system is essential for SC integrity. The impairment of this system underlies POAG-associated pathogenesis, supporting the possibility that Tie2 agonists could be a therapeutic option for glaucoma.

Purpose: To estimate the genetic influences on corneal and ocular higher-order aberrations (HoAs) in the Korean population., Methods: This was a prospective, family-based twin cohort study. A total of 1272 adult twins and their family members, who were part of the Korean Healthy Twin Study from 2007-2011, were included. Corneal and ocular HoAs were measured. The genetic influences on HoAs were investigated by using variance-component methods after adjusting for age and sex. Narrow-sense heritability was calculated. Intraclass correlation coefficients (ICCs) were used to calculate degrees of resemblance among different types of family relationships., Results: A total of 269 monozygotic (MZ) twin pairs (including 176 MZ twin pairs and 93 orphan twins), 50 dizygotic (DZ) twin pairs (including 38 DZ twin pairs and 12 orphan twins), and 739 adult first-degree relatives of twins in 358 families were included. For more than half of corneal HoAs, the narrow-sense heritability estimates were not significant. Horizontal coma was highly heritable among corneal HoAs. The ICCs of horizontal coma from MZ twin pairs, pooled first-degree pairs, and spouse pairs were 0.41, 0.05, and 0.00, respectively. Among ocular HoAs, the estimated narrow-sense heritability of SA was 0.71 with the highest estimates. The ICCs of spherical aberration (SA) from MZ twins, pooled first-degree pairs, and spouse pairs were 0.76, 0.25, and 0.06, respectively., Conclusions: Both corneal and ocular HoAs demonstrated smaller heritability. Corneal HoAs showed low heritability, suggesting individual environmental factors explain most of the variance of these HoAs in the Korean population. Ocular HoAs were moderately heritable.

Purpose: To assess Pentacam (Oculus, Wetzlar, Germany) Scheimpflug quantitative images in evaluating lens density and providing objective measurements to suggest optimal time of cataract surgery in the field of health examination., Methods: Two hundred and twenty-nine eyes with age-related cataract were enrolled. Lens density was measured using Pentacam. All Pentacam images were exported to ImageJ (NIH, Bethesda, Maryland, USA) for quantitative analysis. Average lens density (ALD) and nuclear lens density (NLD) were calculated. Lens density was also evaluated by built-in Pentacam Nucleus Staging (PNS) software. Slit-lamp microscopy was performed for cataract grading according to Lens Opacification Classification System III (LOCS III). The best-corrected visual acuity (BCVA) was measured. All measurements were compared between the cataract surgery and non-cataract surgery groups., Results: The measurements of Pentacam images significantly correlated with LOCS III for nuclear opalescence (NO) and nuclear colour (NC) grading (p<0.01). Pentacam ImageJ showed higher correlation than PNS. The mean NLD was most highly correlated with NO (r=0.8833) and NC (r=0.6815). The maximum ALD was most highly correlated with cortical opacity (r=0.5381). All Pentacam measurements of lens density and BCVA were significantly different between the cataract surgery and non-surgery groups (p<0.01). The optimised cut-off values to perform cataract surgery for mean NLD and maximum ALD were 26 and 74, respectively (p<0.01)., Conclusions: The Pentacam ImageJ method provided objective measurements to evaluate cataracts needing surgery. The method has the potential to be generally applied in the field of health examination and is effective in screening patients with cataract., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

An efficient bit allocation algorithm based on a novel view synthesis distortion model is proposed for the rate-distortion optimized coding of multiview video plus depth sequences in this paper. We decompose an input frame into nonedge blocks and edge blocks. For each nonedge block, we linearly approximate its texture and disparity values, and derive a view synthesis distortion model, which quantifies the impacts of the texture and depth distortions on the qualities of synthesized virtual views. On the other hand, for each edge block, we use its texture and disparity gradients for the distortion model. In addition, we formulate a bit-rate allocation problem in terms of the quantization parameters for texture and depth data. By solving the problem, we can optimally divide a limited bit budget between the texture and depth data, in order to maximize the qualities of synthesized virtual views, as well as those of encoded real views. Experimental results demonstrate that the proposed algorithm yields the average PSNR gains of 1.98 and 2.04 dB in two-view and three-view scenarios, respectively, as compared with a benchmark conventional algorithm.

Purpose: To evaluate the incidence and clinical manifestations of intraoperative floppy iris syndrome (IFIS) according to iris alterations in Korean patients taking α1-adrenergic receptor antagonists (α1-ARAs)., Methods: This is a prospective observational study. Two surgeons performed cataract surgery in 758 eyes of 596 patients over a period of 12 months. Past medical history was reviewed, especially whether patients had been taking systemic α1-ARAs. Ultrasound biomicroscopy was performed to measure the iris thickness of the dilator muscle region (DMR) at half the distance between the scleral spur and the pupillary margin. Pupil diameter was measured and the occurrence of IFIS was recorded. Measurements of the α1-ARA group were compared with those of a control group matched for age and sex., Results: IFIS occurred only in six eyes of four patients on systemic α1-ARA medications (0.8%). Pupil diameter in the α1-ARA medication group and the control group was not significantly different. The difference in mean DMR thickness in patients taking an α1-ARA and in the control group was also not statistically significant (p=0.641). However, within the α1-ARA population, the DMR thickness of IFIS cases was significantly lower than that of non-IFIS cases (p=0.013) CONCLUSIONS: The overall incidence of IFIS was far lower in Korean patients than that reported for western patients. IFIS patients taking α1-ARAs showed significantly greater iris DMR thinning than non-IFIS patients taking α1-ARAs. Our findings indicate that the interaction between α1-ARAs and melanin, which results in iris DMR atrophy and IFIS, is less strong in Korean patients (with dark irises) than western patients.

Purpose: To investigate the incidence and severity of night vision disturbances after implantable collamer lens surgery and to analyze the risk factors., Design: Retrospective, noncomparative study., Methods: Medical charts from 50 eyes of 25 patients who underwent implantable collamer lens implantation were retrospectively reviewed. The incidence and severity of night vision disturbances were evaluated using questionnaires administered 6 months after surgery. Univariate simple and multiple logistic regression analyses were used to detect risk factors associated with postoperative night vision disturbances. Potential risk factors included in the analysis were keratometric value, anterior chamber depth, postoperative residual refractive error, higher-order aberrations, preoperative and postoperative mesopic pupil size, the difference between preoperative and postoperative mesopic pupil size, the difference between mesopic pupil size and implantable collamer lens optic zone diameter, white-to-white diameter, sulcus-to-sulcus diameter, and postoperative implantable collamer lens vaulting. The power, size, optic zone diameter, and toricity of the implantable collamer lens were also included as variables., Results: The incidence of night vision disturbances was 34.0% for halos and 26.0% for glare. Halos were found to be significantly related to the difference between mesopic pupil size and implantable collamer lens optic zone diameter (P = .013), white-to-white diameter of the cornea (P = .028), and implantable collamer lens optic zone diameter (P = .030). For glare, toricity of the implantable collamer lens was revealed as a significant risk factor (P = .047)., Conclusions: Although not severe, the incidence of night vision disturbances after implantable collamer lens implantation was not negligible. Possible risk factors for night vision disturbances include implantable collamer lens optic zone diameter, the difference between mesopic pupil size and implantable collamer lens optic zone diameter, and white-to-white diameter of the cornea for causing halos, and the toricity of the implantable collamer lens for causing glare., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Purpose: To evaluate topographic and tomographic changes in fellow eyes in unilateral keratoconus (KCN) patients by comparing them with normal eyes., Design: Retrospective comparative case series., Methods: Fourteen eyes of 14 patients with unilateral KCN and 34 eyes of 34 refractive surgery candidates were divided into 3 diagnostic groups using a Pentacam rotating Scheimpflug camera: advanced KCN eyes of unilateral KCN (KCN group, 14 eyes), normal fellow eyes of unilateral KCN (fellow eye group, 14 eyes), and refractive surgery candidates (normal group, 34 eyes). Topographic and tomographic parameters, which were obtained from Pentacam using sagittal curvature, elevation, and corneal thickness maps, were compared among the 3 groups. Receiver operating characteristic (ROC) curves were used to identify cutoff points in discriminating between fellow and normal eyes., Results: Keratometric asymmetry, topometric indices, and elevation differences (maximum - minimum) on both the anterior and posterior surfaces were statistically different (P < .05). On ROC curve analysis, keratometric asymmetry and topometric index were best at discriminating fellow eyes from normal, followed by elevation differences (maximum - minimum) on the posterior and anterior cornea surface., Conclusions: Fellow eyes in unilateral KCN showed differences in several parameters that were not detectable with the Pentacam detection program, when compared with normal. However, each single parameter alone is not sufficient to detect early changes; thus, elevation indices as well as indices of anterior curvature should be considered together., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Purpose: To compare visual outcomes and flap stability of LASIK with ultrathin 80- and 120-μm flaps created with a VisuMax femtosecond laser (Carl Zeiss Meditec, Jena, Germany) for moderate to high myopia and to evaluate the effect of corneal flap thickness on outcomes., Methods: In a prospective contralateral eye study, 36 consecutive patients (72 eyes) underwent bilateral LASIK for myopia ranging from -2.00 to -10.00 diopters using the VisuMax femtosecond laser and MEL-80 excimer laser (Carl Zeiss Meditec). One eye of each patient was randomized to have the 80-μm flap and the other to the 120-μm flap created with 200-kHz VisuMax femtosecond laser. Preoperative and postoperative tests included visual acuity, manifest refraction, contrast sensitivity, and flap thickness measured by anterior segment optical coherence tomography. Main outcomes and complications were checked at postoperative 1 week and 1, 3, and 6 months., Results: There were no differences in visual outcome, residual refractive error, or contrast sensitivity between groups during follow-up, except for better uncorrected visual acuity at postoperative 1 day in the 120-μm group. Mean standard deviations of measured flap thickness during follow-up ranged from 3.16 to 3.80 μm in both groups. Opaque bubble layer, a unique complication in femtosecond LASIK, was more frequent in the 80-μm group (7 of 36: 19%) than in the 120-μm flap group (3 of 36: 8%) without a statistically significant difference (P = .301) and was related to thicker central cornea and steeper keratometric value, although it did not influence clinical results. Comparison of the intended versus achieved correction showed no significant differences between groups., Conclusions: LASIK using the VisuMax femtosecond laser supplied good clinical results and flap reproducibility in both the 80- and 120-μm flap groups. Patients with relatively thin cornea may benefit from 80-μm flap LASIK., (Copyright 2013, SLACK Incorporated.)

Purpose: To evaluate the efficacy, safety, and rotational and footplate stability of the STAAR Toric Implantable Collamer Lens (TICL; STAAR Surgical Co) for correction of myopic astigmatism., Methods: In this prospective, consecutive, interventional case series, a TICL was implanted uneventfully in 30 consecutive eyes of 20 patients with myopia and astigmatism. The uncorrected visual acuity, best spectacle-corrected visual acuity, refraction, and astigmatism were measured preoperatively and at last follow-up. To evaluate postoperative axis deviation from the intended axis and footplate displacement, a digital anterior segment photograph was taken after full mydriasis and ultrasound biomicroscopy for the four footplates of the TICL in each eye at last follow-up. Possible risk factors for TICL rotation were analyzed through correlation analysis., Results: After mean follow-up of 7.6 months, the mean refractive astigmatism decreased from 2.43 +/- 1.24 diopters (D) preoperatively to 0.73 +/- 0.47 D postoperatively, and the mean difference between intended and achieved TICL axes was 4.03 +/- 3.39 degrees. The absolute value of TICL rotation had significant correlation with the spherical power of the TICL (P = .037). The footplates of all TICLs were in situ in the ciliary sulcus except for one case in which one of the four footplates was located below the ciliary sulcus., Conclusions: Implantation of the STAAR TICL appears to be an effective and safe method for correction of myopic astigmatism. No clinically significant rotation or footplate displacement of the TICLs was detected postoperatively during mean follow-up of 7.6 months.

Purpose: This study evaluated the effect of high local concentrations of antibiotics on bone repair induced by demineralized bone in rats., Materials and Methods: Seventy-two 3-week-old rats, weighing 200 to 300 g, were used for the experiment. Rats were divided into 4 groups: control group (group 1), saline-impregnation group (group 2), gentamicin-impregnation group (group 3), and tetracycline-impregnation group (group 4). The rats were killed at 3, 8, and 12 weeks after surgery. Samples were stained with hematoxylin-eosin and subjected to the histomorphometric analyses., Results: There were significant differences in new bone formation among groups at all time periods. Comparing differences between groups at each time point, significantly more new bone formation was present in group 2 than in group 1 at 3 weeks, more in group 2 than in group 1 and more in group 2 than in group 4 at 8 weeks, and the most in group 2 among all groups at 12 weeks. In terms of the time period, significantly more new bone formation was observed at 8 weeks during the time period between 3 and 8 weeks, and at 12 weeks during the time period between 3 and 12 weeks., Conclusions: Our result suggests that the bone graft material is most effective when mixed with saline for the regeneration of osseous defects.