Search Results (133)

Background: Smartphones offer a promising tool for monitoring refractive error, especially in underserved areas where there is a shortage of eye-care professionals. We propose a novel method for measuring spherical over-refraction using smartphones. Methods: Specific levels of myopia using positive spherical trial lenses, ranging from 0.00 D to 1.50 D in 0.25 D increments, were induced in 30 young participants (22 ± 5 years). A comparison was conducted between the induced over-refraction and the measurements obtained using a non-commercial mobile application based on the face–device distance measurement using the front camera while the subject was performing a resolution task. Results: Calibrated mobile app over-refraction results showed that 89.5% of the estimates had an error ≤ 0.25 D, and no errors exceeding 0.50 D. Bland–Altman analysis revealed no significant bias between app and clinical over-refraction, with a mean difference of 0.00 D ± 0.44 D (p = 0.981), indicating high accuracy and precision of the method. Conclusions: The methodology used shows high accuracy and precision in the measurement of the spherical over-refraction with only the use of a smartphone, allowing self-monitorization of potential myopia progression. Full article

Objectives: To determine how optometrists in Canada manage their pediatric myopia patients and to assess whether this has changed over time. Methods: In a retrospective chart review, records for children aged 6–10 years who had an eye exam between 2017 to 2021 were reviewed. Children were grouped by presenting refraction (myopes ≤ −0.50 D or pre-myopes ≤ +0.75 D). Up to five unique patients were selected for each age (6, 7, 8, 9, and 10) and initial visit year (2017 to 2021) for each group (myopes and pre-myopes), for a maximum of 250 files per practice. Demographic information, refraction, and recommended interventions were recorded. Logistic regression was used to model the likelihood of being prescribed a myopia control intervention based on patient and optometrist characteristics. Results: A total of 2905 patients (n = 1467 (50%) female) from 15 practices across Ontario, Canada, were included, accounting for 8546 visits. Optometrists predominantly prescribed single-vision spectacle correction as a first-line intervention for myopic children, although this declined from 98.2% in 2017 to 56.7% in 2023. The use of myopia control modalities increased from 1.8% to 43.3% over this same period. Optometrists began recommending myopia control at lower myopic refractive errors over time (−2.63 DS in 2017 vs and −1.49 DS in 2020). Myopia control spectacles were the most commonly prescribed intervention, despite the observation that optometrists are not hesitant to fit contact lenses in younger children. Optometrists who had been in practice longer were more likely to prescribe older forms of myopia control (e.g., bifocals/progressives) than more recent graduates. Conclusions: While single-vision spectacle correction remains a primary approach for initial myopia management in Ontario, Canada, optometrists increasingly recommend myopia control and are initiating interventions earlier. Full article

Purpose: The aim of this study was to compare the one-year efficacy of three spectacle lens designs, highly aspherical lenslets (HALs), horizontally asymmetric peripheral defocus (HAPD) lenses, and standard single vision lenses (SVLs) in slowing myopia progression in school-aged children. Methods: In this prospective, non-randomized study, 57 children, aged 8–17 years, were grouped based on the type of lenses worn: HAL (n = 16), HAPD (n = 21), or SVL (n = 20). Comprehensive ophthalmologic examinations were performed at baseline, 6 months, and 12 months. Outcome measures included spherical equivalent refraction (SER), spherical refraction (SR), cylindrical refraction (CR), and axial length (AL). Data were analyzed using non-parametric tests with significance set at p < 0.05. Results: All groups showed some progression in SER and AL over 12 months. The HAL group demonstrated the smallest median SER change (−0.3 D), compared to HAPD (−0.5 D) and SVL (−0.4 D), though group differences were not statistically significant (p = 0.111). Axial elongation was significantly lower in the HAL group (0.1 mm, IQR: 0.0–0.2 mm) compared to HAPD and SVL (both 0.2 mm, p < 0.0001). CR remained stable in all groups, with no clinically meaningful changes. The HAPD groups showed no advantages over SVL in any parameter. Conclusions: Among the three lens types studied, HAL lenses were the most effective in reducing both refractive and axial myopia progression over 12 months. These findings support their use as a reliable intervention in pediatric myopia control. Full article

Purpose: This retrospective study aimed to compare the efficacy of cycloplegic (CR) versus non-cycloplegic refraction (NCR) methods in detecting refractive errors among children and adolescents. Methods: Electronic data from pediatric ophthalmology clinics at the University Hospital “Sveti Duh”; Zagreb, Croatia, from January 2008 to July 2023, were analyzed. Comprehensive eye examinations, including Logarithmic Visual Acuity tests, subjective refraction, cycloplegic retinoscopy, slit lamp, and fundus examinations, were conducted. Results: The dataset included 1075 individuals, with 180 undergoing NCR and 895 undergoing CR. In premyopes, the NCR group had a longer follow-up (5.04 vs. 3.45 years; p < 0.001) with similar SE progression. In low myopia, NCR showed more negative first visit SE (−1.86 D vs. −1.35 D; p < 0.001) and faster progression (p = 0.01). In high myopia, follow-up was longer in NCR (5.08 vs. 2.08 years; p = 0.03) with no other significant differences. SE progression was highest in 4–6-year-olds and significantly faster in NCR (−0.61 vs. −0.40 D/year; p = 0.05). Conclusions: Cycloplegic refraction is essential for accurately assessing refractive status, especially in cases of low myopia, as it prevents misclassification and ensures precise evaluation in children and adolescents, thereby facilitating the appropriate diagnosis and treatment of refractive errors. Full article

Background/Objectives: Myopia is associated with peripapillary changes, namely, gamma peripapillary atrophy (γPPA) and optic disc ovalization, estimated by the ovality index (OI). These changes have been suggested to be promoted by adduction. Recent studies highlight that near reading significantly contributes to the development and progression of myopia and that the interpupillary distance (IPD) influences vergence amplitudes. While both adduction and convergence are involved during near reading, a potential link between IPD and myopic peripapillary changes has not yet been explored. We, therefore, sought to determine whether IPD is related to the OI or γPPA width. Methods: In this monocentric cross-sectional study, 100 eyes from 100 adults (mean age of 62.6 ± 13.7 years) were analyzed. Axial length (AL), refractive error, and IPD were recorded. The OI and γPPA width were assessed using spectral-domain Optical Coherence Tomography. Pearson correlations and multivariable linear regressions were performed, adjusting for age, gender, and myopia status. Results: IPD showed no significant correlation with the OI (r = 0.001; p = 0.989) or γPPA (r = −0.028; p = 0.789). A weak, non-significant correlation was found between IPD and AL (p = 0.059). In contrast, AL was strongly correlated with both a lower OI and wider γPPA (p < 0.001). Conclusions: These findings suggest that IPD-related biomechanical forces do not influence optic nerve head (ONH) shape or γPPA. Axial elongation remains the key driver of myopic ONH remodeling. Full article

Several soluble mediators are activated during myogenesis and progression, and severe neurodegeneration, with related biomarkers, characterizes high myopia-related retinal atrophy. Targets of oxidative stress, epigenetics and neurogenic inflammation have been reported in the prospecting of some bioindicators to mirror retinal insults occurring in high myopia. The aim of the present study was to assess the expression of a few selected biomarkers belonging to the neurotrophin (NGF and BDNF), oxidative (NO, KEAP1/NRF2), and epigenetic (DNMT3 and HD1) pathways. Sixty-five (65; 76.25 ± 9.40 years) specimens—aqueous, anterior capsule (AC), and lens epithelial cells (LEC)—were collected at the time of cataract surgery and used for ELISA (aqueous) and transcripts analysis (AC/LEC). Biosamples were grouped as emmetrope (23; 81.00 ± 6.70 years); myopia (24; 75.96 ± 7.30); and high (pathological) myopia (18; 70.56 ± 11.68 years), depending on axial length (AL) and refractive error (RE). Comparisons and correlations were carried out between myopic and high-myopic subgroups. NGF and BDNF were lowered in myopic samples; NGF and BDNF transcripts were differentially expressed in LEC, and their expression correlated positively with NGF and negatively with BDNF, with the expression of the αSMA phenotype. NGF and BDNF correlated negatively with NO and nitrites. Oxidative stress (iNOS/NOX1/NOX4 and KEAP1/NRF2) and epigenetic (DNMTα3/HD1) transcripts were upregulated in myopic LEC, compared with emmetropic ones. Herein, we prospect the contribution of NGF and BDNF in both neuroinflammation and neuroprotection occurring in this chronic disease. Full article

Background/Objectives: Inherited retinal diseases (IRDs) are a heterogeneous group of rare eye disorders characterized by progressive photoreceptor degeneration, leading to severe visual impairment or even blindness. This study aims to investigate the prevalence, types, and clinical significance of ophthalmic comorbidities in Portuguese patients with IRDs. Methods: This nationwide Portuguese population-based retrospective study was based on the IRD-PT registry (retina.com.pt). Statistical analysis was conducted using Microsoft^® Excel^® for Microsoft 365 and IBM SPSS Statistics version 29.0.2.0. Informed consent was obtained from all participants. Results: A total of 1531 patients (1254 families) from six centers were enrolled. The cohort consisted of 51% males, with a mean age of 45.8 ± 19.3 years and a mean age at diagnosis of 39.4 ± 19.5 years. Overall, ocular comorbidities were reported in 644 patients (42.1%). In 176 individuals (11.5%), multiple concurrent comorbidities were found. Cataract was the most common comorbidity (21.3%), followed by amblyopia (6.3%) and high myopia (5.9%). Statistically significant associations with ocular comorbidities were observed in isolated progressive IRDs. Specifically, AR RP was associated with cataract (p < 0.001), and gene analysis revealed several significant associations. CRB1 was statistically linked to epiretinal membrane (ERM) (p = 0.003), EYS with cataract (p = 0.001), PROM1 with choroidal neovascularization (CNV) (p = 0.0026), and USH2A with macular hole (p = 0.01). Patients with the RPE65 mutation in Leber congenital amaurosis were associated with ERM (p = 0.019). There was also a significant association between X-linked RP and high myopia (p < 0.001) and CNV in Best disease (p < 0.001); in syndromic IRDs, cataract, cystoid macular edema, and ERM were observed in Usher syndrome, p = 0.002, p = 0.002, and p = 0.005, respectively, and the MYO7A gene was linked to cataract (p = 0.041) and strabismus (p = 0.013); pseudoxanthoma elasticum was significantly associated with CNV (p = 0.002); and foveal hypoplasia was associated with anterior segment dysgenesis (p < 0.001). Conclusions: This study enhances the current understanding of ocular comorbidities in IRDs in Portuguese patients. Common findings were cataract, refractive error, and CME. Stationary IRDs and pattern dystrophies showed fewer concomitant comorbidities, supporting their classification as non-progressive or benign conditions. The significance of registries like IRD-PT cannot be overstated, particularly in the context of rare diseases. These databases serve multiple crucial functions in enabling detailed documentation of disease characteristics and long-term monitoring of disease progression. Full article

Background/Objectives: Keratoconus (KC) is a corneal ectatic disease, characterized by the progressive thinning of the cornea, myopia, and astigmatism, which lead to a decrease in visual acuity. Corneal collagen crosslinking (CXL) is an efficient method of stopping the progression of the disease. The objective of this study is to investigate the endothelial and biomechanical properties of the cornea in keratoconus patients, before and after undergoing corneal collagen crosslinking. Methods: A total of 66 eyes were diagnosed with progressive keratoconus and were recommended epi-off corneal crosslinking. Before the procedure, they were investigated with corneal topography (for minimum, maximum, average keratometry, and corneal astigmatism), specular microscopy (for the following endothelial cell parameters: number, density, surface, variability, and hexagonality), and an ocular response analyzer (for the following biomechanical parameters: corneal hysteresis and resistance factor). All measurements were repeated 1 month and 6 months after the intervention. Results: Several parameters differ according to the Amsler–Krumeich stage of keratoconus: in more advanced stages, patients present higher endothelial cell variability, a lower number of endothelial cells in the paracentral region of the cornea, lower CCT and CRF, and higher keratometry and astigmatism. Endothelial cell variability and number correlate with average keratometry, and there are also strong correlations between topography and CH and CRF. After CXL, the paracentral number of endothelial cells decreased; cell variability and average cell surface increased. Conclusions: More advanced keratoconus cases present with altered corneal biomechanics and topographical parameters, the endothelial layer also being affected proportional to the stage of the disease and also slightly affected after corneal collagen crosslinking. Full article

Background and Clinical Significance: Brittle cornea syndrome (BCS) is a rare, autosomal recessive connective tissue disorder characterized by extreme corneal thinning, high myopia, and increased risk of spontaneous or trauma-induced ocular rupture. It is primarily caused by mutations in the ZNF469 or PRDM5 genes, which regulate extracellular matrix integrity. Early recognition and diagnosis of BCS are crucial to prevent severe visual impairment. This report presents two genetically confirmed cases of BCS in Albanian siblings, emphasizing the diagnostic value of whole-exome sequencing and individualized surgical management strategies. Case Presentation: Two siblings—a 28-year-old male and a 25-year-old female—presented with progressive visual deterioration and marked corneal thinning (<200 µm). Both had a history of spontaneous ocular rupture following minor trauma in the contralateral eye. Detailed ophthalmologic evaluation revealed keratoglobus, high myopia, and irregular astigmatism. Genetic testing identified the homozygous pathogenic variant c.974delG (p.Cys325LeufsX2) in the PRDM5 gene in both cases. The male underwent penetrating keratoplasty (PKP), achieving a best-corrected visual acuity (BCVA) of 20/30. The female initially underwent deep anterior lamellar keratoplasty (DALK), which was converted to PKP intraoperatively due to central endothelial perforation, resulting in a BCVA of 20/25. Both patients remained complication-free over a 7-year follow-up period. Conclusions: These cases highlight the importance of early genetic diagnosis and a tailored surgical approach in managing BCS. Long-term monitoring and protective strategies are essential to prevent complications. Incorporating genetic testing into clinical practice can enhance diagnostic accuracy and guide personalized treatment plans in patients with hereditary corneal dystrophies. Full article

Background: The biomechanical properties of ocular tissues are critical to physiological processes that span ocular development, aging, and disease. The structural integrity of these tissues is important in mediating how the eye responds to strain and stress that pose challenges to physiological homeostasis. In the posterior segment, the peripapillary sclera and lamina separate the intraocular chamber and the fluid-filled subarachnoid space. Degradation of each contribute to pathogenic progression in multiple conditions and are largely determined by the integrity and architecture of collagen fibers, especially type I collagen. Methods: We used atomic force microscopy to measure how stress induced by elevations in intraocular pressure impacts stiffness of the peripapillary sclera and glial lamina in the rat eye and whether changes in stiffness could be influenced by topical treatment of a reparative mimetic of type I collagen. Results: Four weeks of elevated intraocular pressure reduced Young’s modulus in peripapillary sclera and glial lamina, coincident with reduced anterograde transport along the optic projection to the brain. Reduction in tissue stiffness correlated with an increase in fragmented collagen. Topical application of collagen mimetic peptide during the period of elevation countered both. Conclusions: Collagen remodeling occurs in many ocular conditions that influence the peripapillary sclera and glial lamina, including glaucoma and myopia. Our results suggest that topical application of collagen mimetic peptides that intercalate with and repair collagen damaged by disease processes could serve to mitigate changes in tissue stiffness and integrity due to degraded collagen. Full article

Objectives: The aim of this study was to evaluate the effectiveness of using low-dose atropine (ATR) at different instillation frequencies on myopia control in a low-myopia population. Methods: A retrospective cohort study was conducted, and patients using 0.01% ATR and exhibiting a myopia degree ranging from +0.00 to −1.00 diopter (D) were included. A total of 32 and 26 eyes from 32 and 26 individuals were included in the daily group and two-day group, respectively. The main outcomes of this study are the progression of the spherical equivalent refraction (SER) and the elongation of the axial length (AXL). The Mann–Whitney U test and generalized linear model were used to perform the statistical analysis. Results: After a follow-up period of one year, the change in SER was similar between the daily group and two-day group (−0.24 ± 0.09 versus −0.26 ± 0.08, p = 0.393). In addition, there was an insignificant difference in AXL elongation between the daily group and two-day group (0.09 ± 0.07 versus 0.10 ± 0.09, p = 0.655). The trends observed in SER progression (p = 0.604) and AXL elongation (p = 0.779) were statistically identical between the daily group and the two-day group. Conclusions: The results of the two-day use of low-dose ATR regarding SER and AXL control are similar to those with the daily use of low-dose ATR in children with low myopia. Full article

Background: Myopia progression in children is a growing public health concern, with increasing evidence suggesting that lifestyle factors may influence its development. This study aimed to evaluate the potential benefits of regular badminton activity in slowing myopia progression in children. Methods: We analyzed data from 40 children aged 7–14 years with myopia ranging from −1.50 D to −6.25 D who participated in supervised badminton training (three 45 min sessions per week) for 10 months. A control group of 62 myopic children who did not engage in regular physical activity was included. Ophthalmological assessments were performed at baseline and after 10 months. Results: The axial length increased by 0.37 mm in the badminton group compared to 0.56 mm in the control group. The mean change in the spherical equivalent was −0.52 D in the badminton group and −0.84 D in controls. Myopia progression was slower in the group participating in regular physical activity. Conclusions: Regular badminton activity may help reduce the rate of axial elongation and myopia progression in children. These findings support the inclusion of physical activity as a complementary strategy in managing pediatric myopia. However, further research is needed to determine whether this effect is specific to badminton or reflects the general benefit of physical activity. Full article

The aim of this study is to describe the effect that sustained myopic eye growth has on the cellular distribution and function of retinal ganglion cells as myopia progresses over time. Ganglion cell density and the photopic negative response (PhNR) were assessed using immunochemistry and electroretinography (ERG), respectively, on twelve common marmoset eyes (Callithrix jacchus). Myopia was induced in six eyes using negative defocus (three eyes from 2 to 6 months of age, 6-month-old myopes; three eyes from 2 to 12 months of age, 12-month-old myopes). These six treated eyes were compared to six age-matched control eyes. Marmosets induced with myopia for four months showed a reduced pan-retinal ganglion cell density, which continued to decrease in the peripapillary area of marmosets induced with sustained myopia for ten months. Ganglion cell density decreased as a function of axial length. Full-field ERGs revealed a dampening of the PhNR in the 12-month-old, but not 6-month-old myopes. The myopic changes observed in ganglion cell density and retinal function suggest a reorganization of the ganglion cell template during myopia development and progression that increases over time with sustained myopic eye growth and translates into functional alterations at later stages of myopia development in the absence of degenerative changes. It remains unknown whether these changes positively or negatively impact retinal function and health. Full article

Background and Objectives: This study explores the relationship between retinal structure, vascular densities (VD), and the progression of myopia, aiming to identify novel biomarkers for assessing myopia severity. Materials and Methods: A total of 260 eyes were divided into four groups: Emmetropia (EM) (n = 74), Low Myopia (LM) (n = 68), Moderate Myopia (MM) (n = 64), and High Myopia (HM) (n = 54). VD and retinal thickness (RT) in the macular and peripheral quadrants were measured using optical coherence tomography-angiography (OCTA). SVD and DVD were analyzed across the paranasal, peritemporal, perisuperior, and peri-inferior quadrants. Results: Significant differences in superficial vessel density (SVD) were found in the paranasal (EM vs. MM, p = 0.017; EM vs. HM, p = 0.001), peritemporal (EM vs. MM, p = 0.006; EM vs. HM, p = 0.001; LM vs. HM, p = 0.004; MM vs. HM, p = 0.032), perisuperior (EM vs. MM, p = 0.005; EM vs. HM, p = 0.001; LM vs. HM, p = 0.027), and perifoveal quadrants (EM vs. MM, p = 0.003; EM vs. HM, p = 0.008; LM vs. HM, p = 0.004; MM vs. HM, p = 0.012). Deep vessel density (DVD) showed significant differences in the paranasal (p = 0.012–0.022), peritemporal (p = 0.002–0.026), perisuperior (p = 0.003–0.034), perifoveal (p = 0.002–0.017), and peri-inferior (p = 0.002–0.022) quadrants. Retinal thickness was significantly reduced in HM eyes, with the most pronounced reduction in the peritemporal quadrant (mean difference: 16.7 ± 3.2 µm; p < 0.001). Conclusions: Structural and vascular changes in the retina become more pronounced as myopia progresses from moderate to high. The strong correlation between DVD, RT, and myopia severity highlights their potential as reliable biomarkers for monitoring myopia progression through OCTA imaging. These findings provide new insights into the vascular and structural changes underlying myopia and their diagnostic significance. Full article

This study examines the role of violet light (VL) in preventing myopia progression, addressing a critical need in urban environments where VL exposure is limited. Recent research suggests that VL, within the 360–400 nm wavelength range, may reduce myopia risk. To investigate, we conducted spectroscopic measurements in various settings across Tokyo, quantifying VL irradiance in natural sunlight. The results showed high VL levels outdoors, averaging 583 μW/cm² on sunny days and 271 μW/cm² on cloudy days, leading to a weighted annual average of approximately 310 μW/cm². In contrast, indoor environments lacked VL due to UV-blocking materials in windows, glasses, and lighting. This deficiency may contribute to the rising incidence of myopia, particularly in urban areas with reduced outdoor exposure. Our findings highlight the need for innovative solutions to mitigate VL deficiency indoors, such as optimizing architectural designs and artificial lighting to better incorporate VL. This study provides foundational insights for future interventions aimed at reducing myopia risk through improved indoor light environments. Full article