Comparison of keratometric measurements between color light-emitting diode topography and Scheimpflug camera.

BACKGROUND: To determine the agreement of measurements between color light-emitting diode corneal topography (Cassini) and Scheimpflug camera keratometry (Pentacam HR). METHODS: The current retrospective study investigated 117 right eyes of 117 healthy patients before cataract surgery from June 2017 to July 2017. Steep K, flat K, mean K, astigmatism, and axis for both anterior and posterior corneal surface were measured using the two devices. The measured values were converted into J vectors such as J0 and J45. The mean difference for those measurement values were compared between the two instruments, and the agreement was evaluated using the Bland-Altman plot I. RESULTS: There were statistically significant differences in mean K (44.21D [43.34 to 45.34] and 44.30D [43.30 to 45.10] by Cassini and Pentacam [P = 0.004]) and astigmatism (0.90D [0.58 to 1.30] and 0.70D [0.40 to 1.30] by Cassini and Pentacam [P = 0.002]) on the anterior corneal surface and flat K (- 6.21D [- 6.39 to - 6.07] and - 6.30D [- 6.5 to - 6.10] by Cassini and Pentacam [P < 0.001]), mean K (- 6.39D [- 6.54 to - 6.25] and - 6.40D [- 6.60 to - 6.30] by Cassini and Pentacam [P = 0.019]), and astigmatism (0.33D [0.22 to 0.47] and 0.30D [0.15 to 0.40] by Cassini and Pentacam [P = 0.002]) on the posterior corneal surface. The mean difference (= Cassini - Pentacam) with 95% limit of agreement for mean K and astigmatism of the anterior corneal surface were 0.082D (- 0.60 to 0.76) and 0.11D (- 0.73 to 0.95) for measurements obtained by the two instruments, respectively. Regarding keratometric values from the posterior corneal surface, the mean differences for flat K, mean K, and astigmatism were - 0.081D (- 0.42 to 0.26), - 0.030D (- 0.32 to 0.26), and 0.067D (- 0.33 to 0.46), respectively. Intraclass correlation coefficients for steep K, flat K, mean K, and vector J0 were higher than 0.9 in the anterior cornea. Positive correlation in steep K, flat K, mean K, astigmatism, and J0 was found between two devices in both anterior and posterior cornea (P < 0.001). CONCLUSIONS: Corneal refractive power and astigmatism tend to be higher when measured using Cassini than Pentacam HR in both anterior and posterior cornea. The two different devices might not be used interchangeably. TRIAL REGISTRATION: Retrospectively registered. Registration number: KC17RESI0439 .

Through-focus optical characteristics of monofocal and bifocal soft contact lenses across the peripheral visual field.

PURPOSE: To characterise the impact of monofocal soft contact lens (SCL) and bifocal SCLs on refractive error, depth of focus (DoF) and orientation of blur in the peripheral visual field. METHODS: Monofocal and two bifocal SCLs, Acuvue Bifocal (AVB, Johnson & Johnson) and Misight Dual Focus (DF, CooperVision) with +2.0 D add power were modelled using a ray tracing program (ZEMAX) based on their power maps. These SCLs were placed onto the anterior corneal surface of the simulated Atchison myopic eye model to correct for -3.0 D spherical refractive error at the fovea. To quantify through-focus retinal image quality, defocus from -3.5 D to 1.5 D in 0.5 D steps was induced at each horizontal eccentricity from 0 to 40° in 10° steps. Wavefront aberrations were computed for each visual eccentricity and defocus. The retinal images were simulated using a custom software program developed in Matlab (The MathWorks) by convolving the point spread function calculated from the aberration with a reference image. The convolved images were spatially filtered to match the spatial resolution limit of each peripheral eccentricity. Retinal image quality was then quantified by the 2-D cross-correlation between the filtered convolved retinal images and the reference image. Peripheral defocus, DoF and orientation of blur were also estimated. RESULTS: In comparison with the monofocal SCL, the bifocal SCLs degraded retinal image quality while DoF was increased at fovea. From 10 to 20°, a relatively small amount of myopic shift (less than 0.3 D) was induced by bifocal SCLs compared with monofocal. DoF was also increased with bifocal SCLs at peripheral vision of 10 and 20°. The trend of myopic shift became less consistent at larger eccentricity, where at 30° DF showed a 0.75 D myopic shift while AVB showed a 0.2 D hyperopic shift and both AVB and DF exhibited large relative hyperopic defocus at 40°. The anisotropy in orientation of blur was found to increase and change its direction through focus beyond central vision. This trend was found to be less dominant with bifocal SCLs compared to monofocal SCL. CONCLUSIONS: Bifocal SCLs have a relatively small impact on myopic shift in peripheral refractive error while DoF is increased significantly. We hypothetically suggest that a mechanism underlying myopia control with these bifocal or multifocal contact lenses is an increase in DoF and a decrease in anisotropy of peripheral optical blur.

Changes of meibomian glands in the early stage of post hematopoietic stem cell transplantation.

Hematopoietic stem cell transplantation (HSCT) is the most effective cure for hematologic malignancies. Graft-versus-host disease (GVHD) is a major complication following allogeneic HSCT, which significantly affects non-relapse mortality. And ocular manifestations of GVHD are known to occurin 60-90% of patients with chronic GVHD. Although the pathogenesis of ocular GVHD is not clearly known, it is known to progress into inflammation and fibrosis through presentation of antigens on CD4 and CD8 T cells. There is much evidence that the ocular surface and meibomian glands are severely damaged in ocular GVHD patients, and there are few observational studies on the early changes. In this review, we will discuss the various changes in the meibomian glands and ocular surface, and tear dynamics in the early stage following HSCT. These results show that tear film break-up time (TFBUT) decreased and the corneal staining score was significantly higher 2-3 months after HSCT. The upper eyelid and total eyelid meiboscore increased after 3 months following HSCT. The information of the early changes of meibomian glands morphology would be helpful to further examine the pathogenesis of meibomian gland dysfunction.

Morphological evaluation for diagnosis of dry eye related to meibomian gland dysfunction.

The evaluation of morphological changes of the acini in the meibomian glands is important for the diagnosis and management of dry eye related to meibomian gland dysfunction. While several tools have been developed to detect meibomian gland structure, infrared imaging is generally used in clinical settings. Unlike the lipid component analysis of tear film in which quantitative analysis is possible, the meibomian glands are limited to qualitative analysis because of the low image quality of the diagnostic tools. This review describes diagnostic tools, especially in terms of morphological evaluation of the acini, which are visualized by the existence of lipid within them.

POSTERIOR EYE SEGMENT COMPLICATIONS RELATED TO ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION.

PURPOSE: To identify complications in the posterior eye segment in patients who have undergone allogeneic hematopoietic stem cell transplantation (HSCT). METHODS: This retrospective cohort study enrolled 747 patients with hematologic disease who had undergone allogeneic HSCT at Seoul St. Mary's Hospital from January 2009 to December 2012. The posterior eye segment complications were evaluated by reviewing information in medical records at the Department of Hematology and Ophthalmology, including the types, onset times, locations, and resolution times of the complications according to the treatment periods for HSCT; in addition, a subgroup analysis was performed. RESULTS: Among the 635 included patients, 48 (7.6%) experienced complications related to HSCT in the posterior eye segment. Twenty patients were diagnosed with retinal hemorrhage, 16 with cytomegalovirus (CMV) retinitis, and 5 with uveitis. Six patients (37.5%) with retinal hemorrhage had a lesion in Zone 1 and took more time to recover from this complication. Retinal tear (1/16, 6.3%) and rhegmatogenous retinal detachment (2/16, 12.5%) were observed in the patients with CMV retinitis. Among the 20 patients with retinal hemorrhage, 18 (90.0%) had thrombocytopenia, 14 (70.0%) had pancytopenia, and 7 (35.0%) had profound cytopenia. Cytomegalovirus viremia was detected in 16 (72.7%) of the 22 patients with inflammation-associated complications. CONCLUSION: Understanding of each patient's general condition, which is affected by the specific procedures used for HSCT, is important for the diagnosis and management of transplantation-related complications in the posterior eye segment.

Diquafosol promotes corneal epithelial healing via intracellular calcium-mediated ERK activation.

Diquafosol is known as a purinergic P2Y2 receptor (P2Y2R) agonist that stimulates water and mucin secretion from conjunctival epithelial cells and goblet cells, leading to tear film stability in dry eye. However, its effect on corneal epithelial healing has not yet been elucidated. The aim of the present study was to evaluate the effect of diquafosol on corneal epithelial healing in vivo and on P2Y2R-related downstream signaling pathways in vitro. We administered 3% diquafosol ophthalmic solution on 3 mm-diameter epithelial defects made in rat corneas and assessed the wound closure over time. Corneal epithelial healing was significantly accelerated in diquafosol-treated eyes compared to control eyes at 12 and 24 h. During wound healing, P2Y2R staining appeared stronger in the re-epithelized margin near the wound defect. To evaluate whether diquafosol stimulates epidermal growth factor receptor/extracellular-signal-regulated kinase (EGFR/ERK)-related cell proliferation and migration, simian virus 40-transfected human corneal epithelial (THCE) cells were used for in vitro experiments. Cell proliferation was accelerated by diquafosol at concentrations from 20 to 200 µM during 48 h, but inhibited at concentrations over 2000 µM. The intracellular calcium ([Ca(2+)]i) elevation was measured in diquafosol (100 µM)-stimulated cells using Fluo-4/AM ([Ca(2+)]i indicator). [Ca(2+)]i elevation was observed in diquafosol-stimulated cells regardless of the presence of calcium in media, and suramin pretreatment inhibited the calcium response. The effect of diquafosol on phosphorylation of EGFR, ERK and Akt, and cell migration was determined by western blotting and in vitro cell migration assay. Diquafosol induced phosphorylation of EGFR at 2 min post-stimulation, and phosphorylation of ERK at 5 min post-stimulation. Phosphorylation of ERK was attenuated in cells pretreated with suramin or BAPTA/AM ([Ca(2+)]i chelator), and partially with AG1478 (EGFR inhibitor). Likewise, diquafosol-treated cells showed acceleration of gap closure in cell migration assay, which was inhibited by suramin, BAPTA/AM, AG1478, and U0126 (MEK inhibitor). These studies demonstrate that diquafosol is effective in promoting corneal epithelial wound healing and that this effect may result from ERK-stimulated cell proliferation and migration via P2Y2R-mediated [Ca(2+)]i elevation.

The Influence of Overnight Orthokeratology on Ocular Surface and Meibomian Glands in Children and Adolescents.

PURPOSE: The aim of this study was to investigate the influence of overnight orthokeratology (OOK) on ocular surface and meibomian glands in children and adolescents. METHODS: Prospective, noncomparative study included the ocular surface disease index (OSDI), tear osmolarity, corneal and conjunctival fluorescein staining, tear film breakup time (TBUT), the Schirmer I test, and meiboscore using noncontact meibography. Immunofluorescence confocal microscopy of interleukin-1ß (IL1ß), interleukin-6 (IL6), epidermal growth factor (EGF), and matrix metalloproteinase (MMP)-9 using impression cytology filter paper was performed. The tests were performed before and at 6, 12, 24, and 36 months after OOK wear. RESULTS: Fifty-eight subjects using OOK were observed. Significant increases in OSDI score (P=0.0009) and corneal and conjunctival staining score (P<0.0001) were observed compared with baseline values at 36 and 24 months, respectively. Ocular surface and meibomian changes were noted in 2 patients (3.5%). One patient exhibited an increase in OSDI score, concurrent with a decrease in TBUT at 36 months and minor loss of the meibomian gland at the distal portion of the lower lid at 24 months. The other patients exhibited the development of papillary hypertrophy and meibomian gland distortion at 24 months. No significant changes were detected in IL1ß, IL6, EGF, or MMP expression after OOK use. CONCLUSION: Based on the findings, OOK was a relatively safe modality. However, given the potential changes in the meibomian gland and tear film stability, special attention must be paid to children with baseline meibomian gland distortions or a history of allergic conditions.

Ten-year incidence of keratoconus in relation to sex, age, and thyroid gland dysfunction: a nationwide population-based cohort study (2009-2018).

Background: Keratoconus is a corneal ectatic disorder that often leads to visual impairment and may require corneal transplantation. However, its age and gender-based incidence and potential association with thyroid gland dysfunction (TGD) remain poorly understood. This study aims to clarify these aspects and investigate the possible connection between keratoconus and TGD. Methods: We conducted a nationwide population-based cohort study using data from the Korean National Health Insurance Service database. A retrospective chart review was conducted on 4,059,021 patients aged over 20 without underlying corneal diseases in 2009. The end of the review period was at ten years, or until the onset of keratoconus. To evaluate the association with TGD, multivariate Cox regression analysis was used with adjustment of confounding variables such as sex and age. Results: During the review period, 2,334 patients developed keratoconus before the 10-year mark. Females exhibited a higher keratoconus incidence (7.101 per 100,000 person-years) compared to males (5.559) (P<0.001). After adjusting for age, the hazard ratio (HR) for keratoconus was 1.295 times higher [95% confidence interval (CI): 1.193-1.406] in females compared to males. Age groups were stratified in 10-year intervals. The highest incidence of keratoconus was observed in the 20 to 29-year age group (10.695 per 100,000 person-years). All other age groups had significantly lower HR values, with the lowest at 50-59 years (0.508, 95% CI: 0.447-0.577). Keratoconus incidence per 100,000 person-years was 6.227 in subjects without TGD, 6.019 in the hypothyroidism group and 8.287 in the hyperthyroidism group, respectively. Although not statistically significant, individuals with hyperthyroidism showed a higher HR (1.290, 95% CI: 0.939-1.771) for keratoconus when compared to those without TGD, after adjusting for age and sex. Conclusions: This study emphasizes a female predominance in keratoconus incidence and suggests a possible connection between hyperthyroidism and keratoconus. Furthermore, it affirms a higher incidence of keratoconus among young individuals.

An unusual case of an orbital abscess secondary to contralateral sinusitis.

Orbital complications secondary to acute rhinosinusitis can result in permanent blindness or death if not treated promptly and appropriately. Many authors have reported that almost all such patients had abscesses adjacent to the infected sinuses. However, the authors experienced an orbital abscess secondary to contralateral sinusitis. Here, the authors report an 8-year-old patient who had a left superior orbital abscess secondary to a right ethmoidomaxillary sinusitis.

Transcutaneous Electrical Stimulation for the Prevention of Dry Eye Disease after Photorefractive Keratectomy: Randomized Controlled Trial.

Objective: To evaluate the efficacy and safety of transcutaneous electrical stimulation (TES) for the prevention of dry eye after photorefractive keratectomy (PRK). Design: Prospective, single-center, single-blinded, parallel group, placebo-controlled, randomized clinical trial. Participants: Between February 2020 and October 2020, patients at the Samsung Medical Center scheduled to undergo PRK to correct myopia were screened and enrolled. Methods: The participants in the TES group were instructed to use the electrical stimulation device (Nu Eyne 01, Nu Eyne Co) at the periocular region after the operation, whereas those in the control group were to use the sham device. Dry eye symptoms were evaluated preoperatively and postoperatively at weeks 1, 4, and 12 using the Ocular Surface Disease Index (OSDI) questionnaire, the 5-Item Dry Eye Questionnaire (DEQ-5), and the Standard Patient Evaluation for Eye Dryness II (SPEED II) questionnaire. Dry eye signs were assessed using tear break-up time (TBUT), total corneal fluorescein staining (tCFS), and total conjunctival staining score according to the National Eye Institute/Industry scale. The pain intensity was evaluated using a visual analog scale. Main Outcome Measures: Primary outcomes were OSDI and TBUT. Results: Twenty-four patients were enrolled and completed follow-up until the end of the study (12 patients in the TES group, 12 patients in the control group). Refractive outcomes and visual acuity were not different between the groups. No serious adverse event was reported with regard to device use. No significant difference in OSDI and SPEED II questionnaires and the DEQ-5 was observed between the groups in the 12th week after surgery. The TBUT scores 12 weeks after the surgery were 9.28 ± 6.90 seconds in the TES group and 5.98 ± 2.55 seconds in the control group with significant difference (P = 0.042). The tCFS and total conjunctival staining score were significantly lower in the TES group than in the control group at postoperative 4 weeks. Pain intensity at the first week was significantly lower in the TES group than in the control group by 65% (P = 0.011). Conclusion: The application of TES is safe and effective in improving dry eye disease after PRK. Financial Disclosures: The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Effect of pre-fragmentation on efficacy and safety for phacoemulsification in femtosecond laser-assisted cataract surgery: a non-randomized clinical trial.

Background: Ultrasound energy during phacoemulsification results in the endothelial cell loss of cornea. Crystallin lens fragmentation with softening before phacoemulsification can be used with femtosecond laser-assisted cataract surgery (FLACS) device. Methods: This non-randomized clinical trial included patients who underwent cataract surgery and not had corneal opacity. Patients who were not possible to apply the interface on the ocular surface, were excluded. Each subject was allowed to decide the surgical method by himself/herself. Cataract surgery was performed with FLACS (groups I and II) or conventional surgical technique (group III). The FLACS group was further subdivided into two groups according to whether a lens softening procedure was performed (group I) or not (group II). The nuclear density of cataract was objectively classified by Pentacam nuclear staging (PNS), preoperatively. Surgical parameters including total phacoemulsification time (TPT), cumulative dissipated energy (CDE), and the balanced salt solution (BSS) volume consumed, were measured during the surgery. Postoperative visual outcomes were evaluated at three months after the surgery, and corneal endothelial cell count (ECC) loss were calculated based on ECC measured before the surgery and two months after the surgery. Results: Eighty-nine eyes from 89 patients were enrolled. Fifty-three were treated using FLACS (groups I; quadrant pattern with softening of pre-fragmentation, n=31 and II; sextant pattern without softening of pre-fragmentation, n=22) and 36 (group III) with the conventional manual technique. The FLACS groups (groups I and II) had statistically significant lower TPT (P<0.001), CDE (P<0.001), and BSS volumes (P<0.001) used in the nucleus removal step compared to group III. Furthermore, ECC loss in groups I (4.59%±2.57%) and II (6.10%±3.30%) were also statistically lower compared to group III (13.49%±10.55%, P<0.001). From subgroup analysis with the PNS 2, group I showed lower pre-fragmentation time, lower CDE, lower BSS volume used during nucleus removal, and lower ECC loss compared to group II (all P<0.001). Conclusions: Pre-fragmentation using FLACS may reduce intraoperative ultrasound energy and intraocular manipulations compared to conventional cataract surgery.

Conditional Process Analysis for Effective Lens Position According to Preoperative Axial Length.

PURPOSE: To predict the effective lens position (ELP) using conditional process analysis according to preoperative axial length. SETTING: Yeouido St. Mary hospital. DESIGN: A retrospective case series. METHODS: This study included 621 eyes from 621 patients who underwent conventional cataract surgery at Yeouido St. Mary Hospital. Preoperative axial length (AL), mean corneal power (K), and anterior chamber depth (ACD) were measured by partial coherence interferometry. AL was used as an independent variable for the prediction of ELP, and 621 eyes were classified into four groups according to AL. Using conditional process analysis, we developed 24 structural equation models, with ACD and K acting as mediator, moderator or not included as variables, and investigated the model that best predicted ELP. RESULTS: When AL was 23.0 mm or shorter, the predictability for ELP was highest when ACD and K acted as moderating variables (R2 = 0.217). When AL was between 23.0 mm and 24.5 mm or longer than 26.0 mm, the predictability was highest when K acted as a mediating variable and ACD acted as a moderating variable (R2 = 0.217 and R2 = 0.401). On the other hand, when AL ranged from 24.5 mm to 26.0 mm, the model with ACD as a mediating variable and K as a moderating variable was the most accurate (R2 = 0.220). CONCLUSIONS: The optimal structural equation model for ELP prediction in each group varied according to AL. Conditional process analysis can be an alternative to conventional multiple linear regression analysis in ELP prediction.

Corneal Neuro-Regenerative Effect of Transcutaneous Electrical Stimulation in Rabbit Lamellar Keratectomy Model.

Purpose: This study aimed to evaluate the effect of transcutaneous electrical stimulation (TES) on corneal nerve regeneration in rabbits injured from superficial lamellar keratectomy (SLK). Methods: New Zealand White rabbits were used in this experimental study. To induce corneal nerve damage, SLK was performed using a 7.0-mm trephine. TES was applied for 28 days after the corneal nerve injury. Corneal sensitivity, Western blotting, real-time polymerase chain reaction (PCR), and immunofluorescence were performed to observe changes in the corneal tissue. Results: In the 2-Hz and 20-Hz electrical stimulation groups, the degree of corneal wound healing increased by more than 10% compared to the control group, but no significant difference was observed. Conversely, the electrical stimulation (2-Hz or 20-Hz) group showed significantly increased corneal sensitivity compared to the control group. Western blot analysis revealed that small proline-rich protein 1A (SPRR1a), a regeneration-associated protein was significantly increased in the 2-Hz group on days 1 and 7 compared to that in the other groups. Once again, nerve regeneration in the 2-Hz group was supported by the results of PCR, in which a significant increase in the nerve growth factor (NGF) on day 1 was observed compared with the other groups. Moreover, immunofluorescence after 28 days of electrical stimulation showed significant nerve regeneration in the 2-Hz group. Conclusions: TES promoted corneal nerve regeneration in rabbit SLK model. The application of electrical stimulation of 2-Hz frequency was more effective than the 20-Hz frequency, showing potential clinical applications for corneal diseases. Translational Relevance: This study shows how application of TES to the eyes that exhibit corneal nerve damage can improve corneal nerve regeneration examined by histologic analysis.

One-year long-term clinical outcomes following diffractive trifocal toric intraocular lens implantation: retrospective observational case series study.

Background: Trifocal intraocular lens (IOL) provides three foci for the external light to the eye. The reduction of corneal astigmatism makes three foci to clearly focus on the fovea. This study aimed to evaluate one-year clinical outcomes for near, intermediate, and far distance visual acuity and satisfaction in patients implanted with diffractive trifocal toric IOLs. Methods: This retrospective observational case series study was based on the medical records of patients who undergone uncomplicated cataract surgery with implantation of a trifocal toric IOL (POD AY 26P F-T FineVision Toric; PhysIOL SA, Liège, Belgium). Eyes with corneal astigmatism greater than 1.00 diopters were included. Postoperative evaluations included uncorrected near, intermediate, and distance and corrected distance visual acuity; defocus curves; and contrast sensitivity measured at both three months and one-year postoperatively. Subjective satisfaction was evaluated based on three kinds of questionnaires for spectacle dependence, quality of vision, and overall satisfaction. Results: Postoperative uncorrected distance visual acuity and that at 33, 43, 50, 60, and 80 cm at one-year were 0.07±0.08, 0.22±0.11, 0.17±0.11, 0.14±0.10, 0.14±0.10, and 0.15±0.10 logarithm of the minimal angle of resolution (logMAR), respectively. A smooth range of good visual acuity was found on defocus curve. Subjective scores for spectacle dependence, quality of vision, and subjective satisfaction showed no significant differences between three months and one-year postoperatively. The mean amount of IOL axis rotation was 2.14±1.72° (range: 0.2-5.1°) at one-year postoperatively. Conclusions: Implantation of a diffractive trifocal toric IOL for cataract, presbyopia, and astigmatism correction provided good refractive and visual outcomes, relatively smooth range of intermediate vision, and high levels of visual quality and patient satisfaction until one-year after surgery.

Long-term prediction models for vision-threatening diabetic retinopathy using medical features from data warehouse.

We sought to evaluate the performance of machine learning prediction models for identifying vision-threatening diabetic retinopathy (VTDR) in patients with type 2 diabetes mellitus using only medical data from data warehouse. This is a multicenter electronic medical records review study. Patients with type 2 diabetes screened for diabetic retinopathy and followed-up for 10 years were included from six referral hospitals sharing same electronic medical record system (n = 9,102). Patient demographics, laboratory results, visual acuities (VAs), and occurrence of VTDR were collected. Prediction models for VTDR were developed using machine learning models. F1 score, accuracy, specificity, and area under the receiver operating characteristic curve (AUC) were analyzed. Machine learning models revealed F1 score, accuracy, specificity, and AUC values of up 0.89, 0.89.0.95, and 0.96 during training. The trained models predicted the occurrence of VTDR at 10-year with F1 score, accuracy, and specificity up to 0.81, 0.70, and 0.66, respectively, on test set. Important predictors included baseline VA, duration of diabetes treatment, serum level of glycated hemoglobin and creatinine, estimated glomerular filtration rate and blood pressure. The models could predict the long-term occurrence of VTDR with fair performance. Although there might be limitation due to lack of funduscopic findings, prediction models trained using medical data can facilitate proper referral of subjects at high risk for VTDR to an ophthalmologist from primary care.

Association of Serum Lipid Level with Meibum Biosynthesis and Meibomian Gland Dysfunction: A Review.

The primary role of meibomian glands (MGs) is to actively synthesize and secret lipids and proteins spread onto the tear film, and the glandular lipids promote tear stability, prevent evaporation, and reduce friction. Meibomian gland dysfunction (MGD) is the leading cause of dry eye disease and one of the most common ophthalmic problems worldwide. MGs are densely innervated and regulated by hormones and growth factors. However, since the polar and nonpolar lipids are produced through processes in MGs that are not completely understood, a relevant question has been raised: Would the altered systemic lipids metabolism affect the physiology and structure of MGs? This review introduces the recent update regarding the relationships between serum lipid and MGD in clinical and basic research while providing answers to this question. A causal relationship remains to be established; however, serum lipid level or dyslipidemia may be related to MGD directly or indirectly, or both. Further studies are warranted to establish the role of serum lipid level and meibocyte differentiation/maturation and lipid synthesis.

Prediction of Visual Outcomes After Diabetic Vitrectomy Using Clinical Factors From Common Data Warehouse.

Purpose: We sought to analyze the visual outcome and systemic prognostic factors for diabetic vitrectomy and predicted outcomes using these factors. Methods: This was a multicenter electronic medical records (EMRs) review study of 1504 eyes with type 2 diabetes that underwent vitrectomy for proliferative diabetic retinopathy at 6 university hospitals. Demographics, laboratory results, intra-operative findings, and visual acuity (VA) values were analyzed and correlated with visual outcomes at 1 year after the vitrectomy. Prediction models for visual outcomes were obtained using machine learning. Results: At 1 year, VA was 1.0 logarithm of minimal angle resolution (logMAR) or greater (poor visual outcome group) in 456 eyes (30%). Baseline visual acuity, duration of diabetes treatment, tractional membrane, silicone oil tamponade, smoking, and vitreous hemorrhage correlated with logMAR VA at 1 year (r = 0.450, -0.159, 0.221, 0.280, 0.067, and -0.105; all P ≤ 0.036). An ensemble decision tree model trained using all variables generated accuracy, specificity, F1 score (the harmonic means of which precision and sensitivity), and receiver-operating characteristic curve area under curve values of 0.77, 0.66, 0.85, and 0.84 for the prediction of poor visual outcomes at 1 year after vitrectomy. Conclusions: Visual outcome after diabetic vitrectomy is associated with pre- and intra-operative findings and systemic factors. Poor visual outcome after diabetic vitrectomy was predictable using clinical factors. Intensive care in patients who are predicted to result in poor vision may limit vision loss resulting from type 2 diabetes. Translational Relevance: This study demonstrates that a real world EMR big data could predict outcome after diabetic vitrectomy using clinical factors.

Assessment for Macular Thickness after Uncomplicated Phacoemulsification Using Optical Coherence Tomography.

PURPOSE: Macular edema including cystoid macular edema is one of the main causes of unfavorable visual outcomes after cataract surgery. The macular thickness and the occurrence of macular edema after uncomplicated cataract surgery was evaluated using optical coherence tomography (OCT) in this study. METHODS: Macular map images were taken by OCT before surgery and at 1 week, 1 month, and 2 months postsurgery. The subjects were classified into two groups (group 1, patients with no macular edema; group 2, patients with macular edema). Group 2 was defined as increase in central macular thickness (CMT) by 30% compared with that before surgery. The risk factors for macular edema were evaluated. Group 2 was divided into two subgroups: subclinical macular edema (group 2A) and cystoid macular edema (group 2B) and they were assessed in terms of the clinical course of best-corrected visual acuity and CMT. RESULTS: A total of 376 patients were enrolled in this study, of which 36 (9.57%, group 2) showed macular edema measured by OCT after the surgery. Univariate analysis for group 1 and 2 revealed that intracameral injection of epinephrine during phacoemulsification was associated with the development of macular edema. In group 2, five patients (1.33%) developed cystoid macular edema. Statistically significant differences in the clinical course of CMT were observed at 2 months (201.2 ± 23.1, 250.0 ± 29.8, and 371.0 ± 160.3 in group 1, group 2A, and group 2B, respectively; p < 0.001) and 1 month postoperatively (198.5 ± 23.6, 237.8 ± 40.9, and 314.0 ± 104.5 in group 1, group 2A, and group 2B, respectively; p < 0.001). Group 2B required additional treatment and eventually achieved best-corrected visual acuity of >0.2 with CMT in the normal range. CONCLUSIONS: The intracameral injection of epinephrine may cause macular edema after uncomplicated cataract surgery. Examination of CMT using OCT is recommended for the early detection of macular edema.

Comparison of penetrating femtosecond laser-assisted astigmatic keratotomy and toric intraocular lens implantation for correction of astigmatism in cataract surgery.

This study tried to compare the clinical outcomes of femtosecond laser-assisted astigmatic keratotomy (FSAK) and toric intraocular lens (IOL) implantation for astigmatism correction and identify factors affecting the efficacy of FSAK and toric IOL implantation in astigmatism correction. This retrospective case series comprised patients with corneal astigmatism ranging between 0.5 D and 4.5 D. Patients underwent FSAK or toric IOL implantation for cataract treatment and correction of astigmatism at the Samsung Medical Center, a tertiary surgical center, between April 2016 and December 2018. All patients underwent examination before and at three months after the surgery for comparative evaluation of refractive astigmatism, corneal high order aberrations and irregularity index. The astigmatism correction was analyzed by the Alpins method. Subgroup analysis of preoperative factors was based on the extent of target-induced astigmatism (TIA), the degree of astigmatism, and astigmatism classification based on topography. Thirty-one eyes underwent toric IOL implantation and 35 eyes underwent FSAK. The refractive astigmatism was significantly decreased in both toric IOL (P = 0.000) and FSAK group (P = 0.003). The correction index (CI) of refractive astigmatism was 0.84 ± 0.39 in the toric IOL and 0.71 ± 0.60 in the FSAK group. There was no difference between the two groups (P = 0.337). The CI of the FSAK group was significantly lower than in the toric IOL group when TIA was more than 1.5 D (P = 0.006), when correcting against-the-rule (P = 0.017), and limbus-to-limbus astigmatism (P = 0.008). In conclusion, toric IOL implantation is an effective and safe procedure for correcting preoperative astigmatism in cataract surgery in the short-term observation.

Effects of the re-esterified triglyceride (rTG) form of omega-3 supplements on dry eye following cataract surgery.

BACKGROUND/AIMS: To evaluate the clinical outcomes of the systemic re-esterified triglyceride (rTG) form of omega-3 fatty acids in patients with dry eye symptoms after cataract surgery. METHODS: This prospective comparative cohort study comprised 66 patients complaining of new-onset non-specific typical dry eye 1 month after uncomplicated cataract surgery. Subjects were randomly allocated into control and omega-3 groups based on administration of the systemic rTG form of omega-3 fatty acids for 2 months, in addition to use of artificial teardrop. Ocular surface parameters (Schirmer's test, tear break-up time, corneal staining score and matrix metalloproteinase-9 (MMP-9)) and subjective questionnaire results (Ocular Surface Disease Index (OSDI)) and Dry Eye Questionnaire [DEQ]) for dry eye were evaluated before and after omega-3 supplementation. RESULTS: Two months after omega-3 supplementation, the Oxford score was lower in the omega-3 group than in the control group. There was an improvement of subjective symptom scores of OSDI and DEQ in the omega-3 group (both p<0.05). The ratio of increasing MMP-9 level in the omega-3 group was lower than that in the control group (p=0.027). CONCLUSION: The rTG form of omega-3 supplementation might be related to reduction of ocular surface inflammation rather than secretion of tears, and it might be effective for non-specific typical dry eye after uncomplicated cataract surgery. TRIAL REGISTRATION NUMBER: NCT04411615.