Current Eye Research最新文献

Purpose: Experimental studies of Dry Eye Disease (DED) using animal models are hampered by the lack of reliable, easy-to-use assays that can adequately diagnose disease or monitor effects of novel treatments. The Oculus Keratograph 5 M, an advanced keratography unit (AKU), has shown promise, enjoying recent clinical use. We assessed whether this AKU could be used in DED studies in the rabbit, perhaps the ideal experimental animal for this disease.

Methods: All measures were made in strictly controlled temperature and humidity spaces. A panel of AKU parameters was measured in 15 New Zealand White rabbits at baseline, after Concanavalin A induced DED, and following recovery. Eyelid aperture and corneal irregularity were also measured. A subset of these parameters was measured in patients and compared with those from rabbits.

Results: AKU parameters in both humans and rabbits showed similar patterns and coefficients of variation (CV). Measurements of tear and eyelid architecture were more reproducible than tear film function in both species. The CV for most parameters were less than the observed changes in the respective parameters after DED induction. In rabbits, all parameters improved returning close to baseline following DED recovery. In the rabbit, additional measures (eyelid aperture and corneal irregularity) not traditionally associated with DED, also demonstrated changes that evolved over the development and recovery of DED.

Conclusions: AKU technology can effectively detect changes in multiple parameters during the evolution and resolution of DED in rabbits. DED parameters showed similar patterns for most variables in both humans and rabbits demonstrating great potential of this device in translational research. The AKU can also follow additional parameters evaluating the responses of the lacrimal functional unit. Our findings document the applicability of this technology for translational studies of DED and underscores its potential to further refine understanding of the disease pathophysiology.

Purpose: Long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) in the retina play crucial roles in myopia; however, their regulatory mechanisms remain unclear. This study aimed to investigate significant genes and related signaling pathways associated with myopia by constructing and analyzing competitive endogenous RNA (ceRNA) networks within the retina.

Materials and methods: We investigated the expression patterns of lncRNAs, circRNAs, microRNAs (miRNAs), and messenger RNAs (mRNAs) within the retina using a form-deprivation myopia mouse model to elucidate their regulatory mechanisms in myopia. Transcriptomic sequencing was performed on retinal cells obtained from a mouse myopia model, followed by differential expression and functional enrichment analyses. Relevant ceRNA networks (lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA) were constructed. Key pathways in these networks were validated via quantitative real-time polymerase chain reaction and western blotting, while Immunohistochemistry and single-cell sequencing analyses were conducted to analyze significant gene distribution.

Results: The model exhibited approximately -6D diopters after 14 days of form deprivation. Transcriptomic analysis identified 187 differentially expressed lncRNAs (DE lncRNAs), 22 DE circRNAs, 24 DE miRNAs, and 368 DE mRNAs. Enrichment analysis linked these differentially expressed genes to various retinal functions and pathways. Validation revealed that the TCONS_00102163-mmu-miR-540-3p-Kcnq2, TCONS_00127926-novel_234-Tepp, and novel_circ_0001750-mmu-miR-212-5p-Sstr3 pathways in the retina were involved in regulating myopia. All experiments were conducted in three independent biological replicates.

Conclusions: This study systematically elucidated the synergistic regulatory mechanisms of non-coding RNAs in the development of myopia by constructing a ceRNA regulatory network in the retina, and further validated key regulatory axes. This provides an important theoretical foundation for understanding the molecular mechanisms of myopia and developing novel intervention strategies.

Purpose: Presbyopia is an age-related condition characterized by diminished near-vision, primarily due to changes in the lens' adaptive capacity. Shear Wave Ultrasound Elastography (SWE) offers a novel/noninvasive method to measure lens stiffness and could potentially enhance our understanding of presbyopia's development. We aimed to use SWE to assess the elasticity of the human lens and explore the correlation between lens flexibility, age, presbyopia, and accommodation capacity.

Methods: A cross-sectional analysis was conducted with 84 participants (mean age = 39.61 ± 9.60) from a government hospital in Serdang, Selangor, Malaysia. Eligibility was confirmed through refractive error and visual acuity tests. Selected participants underwent SWE scanning, and measurements of accommodation and presbyopia were taken. Statistical analysis included descriptive summaries and Pearson correlation coefficients to examine relationships between lens elasticity age, presbyopia, and amplitude of accommodation.

Results: The analysis demonstrated a weak correlation between lens elasticity and age in nonpresbyopic group (r = 0.289) while positive strong correlation in presbyopic group (r = 0.674). A strong positive correlation was observed between lens elasticity and presbyopia in presbyopic group (r = 0.612). Moreover, there was a negative correlation with accommodation in both groups, (r = -0.358) for nonpresbyopic and (r = -0.493) presbyopic group.

Conclusions: While lens elasticity diminishes with age, changes in ocular biomechanical properties impact lens function, particularly affecting near vision. Importantly, SWE is found to be an effective tool for assessing age-related changes in lens elasticity and presbyopia across various age groups, highlighting its potential for broader clinical application in diagnosing and understanding presbyopia.

Purpose: To characterize retinal mitochondrial function and its relationship with intraretinal thicknesses in healthy adults.

Methods: Retinal flavoprotein fluorescence (FPF), a marker of mitochondrial function, was measured using the OcuMet Beacon (OcuSciences, Inc., Ann Arbor, MI), and a stress index (SI) was computed using Enhanced Retinal Metabolic Analysis software 2.0 (RMA). After lens compensation, mean FPF in the macula and optic nerve head (ONH) was obtained. The macular SI summarizes FPF heterogeneity, while the ONH SI reflects the extent to which ONH FPF exceeds a normative threshold. Intraretinal layer thicknesses and total retinal thickness (TRT) were measured via spectral-domain OCT (AngioVue, Optovue, Inc., ver. 2018.1.0.43) using 6 x 6 mm macular scans. A total of 75 healthy adults (mean age ± SD: 56.1 ± 21.7 years; range: 23-89) were imaged.

Results: Macular and ONH FPF were inversely correlated with TRT (p < 0.01), retinal nerve fiber layer (RNFL) thickness (p < 0.05), and ganglion cell-inner plexiform layer (GCIPL) thickness (p < 0.01). ONH FPF also showed a negative correlation with the thickness of the OPL-EZ region-defined as the area between the posterior boundary of the outer plexiform layer (OPL) and the anterior boundary of the ellipsoid zone (EZ) (r = -0.24, p = 0.044)-and the photoreceptor layer (PR) (r = -0.34, p = 0.003). Age was significantly associated with FPF and with several intraretinal layer thicknesses, including TRT, RNFL, GCIPL, OPL-EZ region, and PR (all p < 0.05). However, after adjusting for age, associations between FPF and intraretinal thicknesses were no longer significant (all p > 0.05).

Conclusion: This study is the first to examine the relationship between retinal mitochondrial function and intraretinal layer thicknesses in healthy adults. Findings suggest that age mediates the observed associations.

Purpose: To develop an automated method for segmenting and quantifying the choriocapillaris (CC) layer using swept-source optical coherence tomography angiography (SS-OCTA), aimed at evaluating CC perfusion changes in diabetic retinopathy (DR) patients and facilitating clinical research.

Methods: We proposed a traditional image processing algorithm combining shadow compensation and intensity gradients to segment the CC layer in eyes at various stages of DR. The algorithm was refined for artifact removal in CC blood flow analysis. It was tested on 25 manually segmented cases including normal eyes, non-proliferative diabetic retinopathy (NPDR), and proliferative diabetic retinopathy (PDR). CC blood flow quantification was performed on 69 subjects.

Results: The segmentation algorithm showed high accuracy, with a maximum mean positional error of 4.086 ± 4.304 μm for Bruch's membrane (BM) and a minimum average DICE coefficient of 0.831 for CC segmentation. The CC flow deficit percentage (FD%) for normal eyes, NPDR eyes, and PDR eyes were 9.79 ± 2.29%, 12.25 ± 3.89%, and 15.35 ± 4.00%, respectively, with significant differences between groups (p < 0.05).

Conclusions: The automated CC segmentation and quantification algorithm developed in this study provides an accurate and reliable method for assessing CC in DR patients. This method has potential for widespread clinical application in evaluating CC perfusion changes across various stages of DR.

Purpose: By observing the dry eye index, meibomian glands (MGs), corneal dendritic cells (DCs) and nerve fiber density (CNFD) in patients who have been wearing soft contact lenses continuously and those who have stopped wearing them before corneal refractive surgery, analyze the characteristics of soft contact lens-related MGs abnormalities.

Methods: Collected patient datas and divided into a control group, a wearing group and a stop wearing group. All patients underwent oculus keratography examination, the wearing and the stop wearing group underwent confocal microscopy examination.

Results: The MGs defect rate and the number of obstructive MGs in the wearing group were significantly higher than those in the stopping group (p < 0.01). The MG scores of the wearing group were significantly higher than those of the control group (p < 0.01). The wearing group had an increase in DCs and a decrease in central CNDF compared to the stopping group (p < 0.01). The duration of continual use of contact lenses correlated with the MGs defect rate and the number of obstructive MGs(p < 0.05). The length of time since discontinuation correlated with the number of obstructive MGs, central DCs density, and central CNFD(p < 0.01).

Conclusion: Long term continuous wearing of soft contact lenses leads to MGs abnormalities, and DCs increased in all directions of the cornea, CNFD decreased in the central area of the cornea. There were immune and neurological factors involved in soft contact lens-related MGs abnormalities in middle-aged and young people, and the severity varies among individuals. When stopped wearing soft contact lenses exceed one week, the morphological changes of MGs occured earlier.

Purpose: To evaluate the effects of nephropathy and neuropathy on short-term anatomical and functional responses to intravitreal anti-VEGF treatment in patients with diabetic macular edema (DME), using optical coherence tomography angiography (OCTA).

Materials and methods: This prospective study included 34 eyes from 34 DME patients who received three monthly intravitreal anti-VEGF injections. Patients were stratified based on renal function (eGFR ≥90 vs. <90 mL/min/1.73 m²; UACR <30 vs. ≥30 mg/g) and the presence of diabetic neuropathy confirmed by EMG. Functional (BCVA) and anatomical (central macular thickness, vessel densities in the superficial and deep capillary plexus, and FAZ area) changes were compared across subgroups using OCTA at baseline and 3 months.

Results: Of all patients, BCVA improved significantly (p < 0.05) and central macular thickness (CMT) decreased significantly (p < 0.01) after treatment. However, eyes with nephropathy (eGFR <90) showed smaller reductions in CMT compared to those without nephropathy, though the difference was not statistically significant (p = 0.68). Patients with neuropathy showed less improvement in BCVA and reduced changes in superficial and deep vessel densities. OCTA parameters showed modest, variable responses across all subgroups.

Conclusions: Nephropathy and neuropathy do not seem to affect the functional recovery response to short-term intravitreal anti-VEGF therapy for DME. Nephropathy affects peripapillary vascular density.

Purpose: Myopia is a significant public health concern with increased risk of ocular complications. Intense Foveal Red Light (IFRL) therapy has been explored in myopia control, but its efficacy at the pre-myopic stage remains underexplored. The use of this therapy in a population without a myopia diagnosis may offer a new window for the prophylactic application of IFRL therapy. The purpose of this meta-analysis is to determine the effectiveness of IFRL therapy in children with pre-myopia.

Methods: PubMed, Embase, and the Cochrane Library were systematically searched for studies investigating the effects of IFRL therapy on myopia incidence, changes in axial length (AL), choroidal thickness (CT), and cycloplegic spherical equivalent refraction (SER). Two independent reviewers screened studies, extracted data, and assessed the risk of bias. Meta-analyses were conducted using random-effects models to estimate the pooled effect sizes.

Results: Of 365 studies identified, 4 met the criteria, totaling 619 participants (mean age 8.48 years, 51.8% female). At 6 months, IFRL significantly reduced myopia incidence (Risk Difference [RD] - 0.1; 95% CI -0.15 to -0.05; p < 0.01), with benefits persisting at 12 months (RD -0.17; 95% CI -0.26 to 0.09; p < 0.01). IFRL also reduced AL at 6 months (Mean Difference [MD] - 0.12 mm; 95% CI -0.16 to -0.09; p < 0.01) and 12 months (MD -0.18 mm; 95% CI -0.23 to -0.14; p < 0.01), increased CT (MD 22.34 µm; 95% CI 5.45-39.24; p < 0.01), and improved SER at 6 (MD 0.27 D; 95% CI 0.23 to 0.32; p < 0.01) and 12 months (MD 0.36 D; 95% CI 0.27-0.46; p < 0.01).

Conclusion: IFRL effectively reduced myopia incidence, AL, and improved SER and CT. These findings support further research on its long-term efficacy and safety, particularly regarding potential adverse effects and durability of outcomes. Overall, IFRL may offer a preventive strategy for pre-myopic children.

Purpose: Financial incentives have proven successful in addressing health behaviors associated with several chronic diseases and may represent a potential method to improve adherence to follow-up eye examinations from vision screening programs. The study was conducted to determine the effect of financial incentives on follow-up adherence in the Alabama Screening and Intervention for Glaucoma and eye Health through Telemedicine.

Methods: This study enrolled eligible patients receiving care at three Federally Qualified Health Centers to undergo screening for refractive error and ocular diseases. Follow-up appointments for continued care were made for patients suspected to have uncorrected refractive error or ocular disease. A subset of patients (n = 187) received a financial incentive while a control group did not (n = 234). Follow-up attendance within 6 months was compared with Poisson's models between incentivized and non-incentivized groups for all referrals and across specific disease states.

Results: Among 187 patients with and 234 without incentive, there was a significantly higher rates of follow-up in the incentivized group (83.4% incentivized vs. 74.4% non-incentivized, p = .05) overall. There was a significantly higher rate of attendance for patients referred for diabetic retinopathy (p = .02) and refractive error (p = .02), but not glaucoma (p = .46), glaucoma suspect (p = .70), ocular hypertension (p = .22), and cataract (p = .29). After matching across groups, these differences were less pronounced and only remained significant for diabetic retinopathy (p = .04).

Conclusion: Patients receiving financial incentive had a higher follow-up rate within 6 months. These differences where primarily driven by patients referred for refractive error and diabetic retinopathy. However, once matched for baseline covariates, this improvement was not seen in the overall group. This suggests that incentives may not be an effective method to improve adherence to vision screening in this setting especially for glaucoma screening.

Purpose: This study aimed to compare subjective (questionnaire-based) and objective (dosimeter-based) measurements of children's outdoor activity, to improve assessment methods for future research on the potential impact of outdoor activity on myopia development.

Methods: The study was conducted among children aged 5 to 11 years in Lisbon, Portugal. Subjective data on after-school outdoor activities during weekdays were collected using the "Myopia Risk Assessment Worksheet," completed by parents to report their child's typical after-school outdoor time. Objective measurements for the same period were obtained using UV dosimeters worn by participants, recording their exposure to solar radiation between 4:00 PM and 9:00 PM on weekdays. The analysis compared these two data sources to evaluate their agreement and to assess the accuracy of self-reported after-school outdoor activity.

Results: The results indicated a moderate correlation (rs = 0.417; p < 0.001) between questionnaire responses and dosimetric data, with self-reported data typically underestimating outdoor exposure compared to dosimetric measurements. The median difference was -0.25 h/day (95% CI: -0.52 to 0.15 h/day), indicating no significant systematic bias in the overall sample. However, variability in differences increased with longer outdoor times, as shown by a positive slope of 0.540 (p < 0.001) in the regression of absolute residuals on average outdoor time.

Conclusions: This study demonstrates that lifestyle questionnaires and dosimetric measurements yield moderately correlated estimates of weekly UV exposure, with minimal differences between them. Combining subjective and objective methods enhances the accuracy of assessing children's outdoor exposure, an essential factor in developing effective myopia prevention strategies.