Peripheral Choroidal Response to Localized Defocus Blur: Influence of Native Peripheral Aberrations.

Purpose: This study aims to examine the short-term peripheral choroidal thickness (PChT) response to signed defocus blur, both with and without native peripheral aberrations. This examination will provide insights into the role of peripheral aberration in detecting signs of defocus. Methods: The peripheral retina (temporal 15°) of the right eye was exposed to a localized video stimulus in 11 young adults. An adaptive optics system induced 2D myopic or hyperopic defocus onto the stimulus, with or without correcting native peripheral ocular aberrations (adaptive optics [AO] or NoAO defocus conditions). Choroidal scans were captured using Heidelberg Spectralis OCT at baseline, exposure (10, 20, and 30 minutes), and recovery phases (4, 8, and 15 minutes). Neural network-based automated MATLAB segmentation program measured PChT changes from OCT scans, and statistical analysis evaluated the effects of different optical conditions over time. Results: During the exposure phase, NoAO myopic and hyperopic defocus conditions exhibited distinct bidirectional PChT alterations, showing average thickening (10.0 ± 5.3 µm) and thinning (-9.1 ± 5.5 µm), respectively. In contrast, induced AO defocus conditions did not demonstrate a significant change from baseline. PChT recovery to baseline occurred for all conditions. The unexposed fovea did not show any significant ChT change, indicating a localized ChT response to retinal blur. Conclusions: We discovered that the PChT response serves as a marker for detecting peripheral retinal myopic and hyperopic defocus blur, especially in the presence of peripheral aberrations. These findings highlight the significant role of peripheral oriented blur in cueing peripheral defocus sign detection.

Peripheral Refraction Using Ancillary Retinoscope Component (P-ARC).

Purpose: To assess the agreement of retinoscope-based peripheral refraction techniques with the criterion standard open-field autorefractor. Methods: Fifty young adults (mean age, 24 ± 3 years) participated in this study. Two masked, experienced senior examiners carried out central refraction and peripheral refraction at the temporal 22° (T22°) and nasal 22° (N22°) eccentricities. Peripheral refraction techniques were (a) peripheral refraction using ancillary retinoscope component (P-ARC), (b) retinoscopy with eye rotation, and (c) open-field autorefractor. Peripheral refraction with retinoscopy values was compared with an open-field autorefractor (Shinn Nippon NVision-K) to assess the agreement. All measurements were taken from the right eye under noncycloplegic conditions. Results: The mean difference ±95% limits of agreement of peripheral refraction values obtained using P-ARC from T22° (+0.11 diopters [D] ± 1.20 D; P = 0.20) or N22° (+0.13 D ± 1.16 D; P = 0.13) were comparable with open-field autorefractor. The eye rotation technique compared to autorefractor showed a significant difference for T22° (+0.30 D ± 1.26 D; P = 0.002); however, there was an agreement for N22° (+0.14 D ± 1.16 D; P = 0.10). With respect to the identification of peripheral refraction patterns, examiners were able to identify relative peripheral hyperopia in most of the participants (77%). Conclusions: Peripheral refraction with P-ARC was comparable with open-field autorefractor at T22° and N22° eccentricities. Peripheral retinoscopy techniques can be another approache for estimating and identifying peripheral refraction and its patterns in a regular clinical setting. Translational Relevance: Retinoscope with P-ARC has high potential to guide and enable eye care practitioners to perform peripheral refraction and identify peripheral refraction patterns for effective myopia management.

[A study on the distribution characteristics of peripheral retinal defocus in children and adolescents].

Objective: To explore the distribution characteristics of peripheral retinal defocus in children and adolescents. Methods: This cross-sectional study included 500 individuals aged 3 to 18 years, who visited the People's Hospital of Lincang, the First Affiliated Hospital of Dali University and Dali Ophthalmology Hospital between January and December 2021. Data of the right eye of each participant was analyzed. There were 226 males (45.20%) and 274 females (54.80%), with an average age of (10.79±3.79) years. All participants underwent post-cycloplegic refraction, optical biometry, and intraocular pressure measurement to obtain spherical equivalent, average corneal curvature, axial length, and intraocular pressure. Multispectral refraction topography was performed to obtain topographic maps and values at various field angles and orientations of peripheral retinal defocus. Based on multispectral refraction topography, peripheral retinal defocus values were categorized as crater type, hemilateral upturn type, saddle type, and relatively flat type. The distribution of different refractive states was analyzed. Results: The spherical equivalent of the 500 participants was(-1.51±2.61) D, axial length was (24.10±1.28) mm, and average corneal curvature was (43.20±1.22) D. Among the 500 eyes, 382 exhibited hyperopic peripheral retinal defocus values, with 316 eyes (82.72%) being myopic. Myopic peripheral retinal defocus values were observed in 118 eyes, with 15 eyes (12.72%) being myopic. Among different types of peripheral retinal defocus values, 112 eyes (22.4%) exhibited a crater type, 153 eyes (30.6%) exhibited a hemilateral upturn type, 107 eyes (21.4%) exhibited a saddle type, and 128 eyes (25.6%) exhibited a flat type. The proportion of myopia was 82.14% (92 eyes), 69.28% (106 eyes), 60.75% (65 eyes), and 3.90% (5 eyes), respectively. The peripheral retinal defocus values at 15°, 30°, and 45° were (0.01±0.08) D, (0.06±0.21) D, and (0.20±0.37) D, respectively. The peripheral retinal defocus values at temporal, inferior, nasal, and superior locations were (0.58±0.69) D, (0.52±0.63) D, (0.21±0.64) D, and (-0.26±0.67) D, respectively. Notably, the superior primarily manifested as myopic, while the others were predominantly hyperopic. Conclusions: Approximately three-fourths of children and adolescents exhibit hyperopic peripheral retinal defocus values, with a higher prevalence of myopia in this subgroup. The hyperopia peripheral retinal defocus value increases with the distance from the retina to the macula. The peripheral retinal defocus values between superior and inferior, nasal and temporal locations are asymmetrical, with the temporal hyperopic peripheral retinal defocus value being most prominent and the superior myopic peripheral retinal defocus value being most evident.

The Relationship between Myopia and Obesity in Adults.

PURPOSE: To investigate the relationship between myopia and obesity through direct measurements of fat content. METHODS: A cross-sectional study used a stratified, multistage survey, the Korea National Health and Nutrition Examination Survey (2008-2010). Subjects 19 years or older (n = 10,305) were included. Participants were divided into three groups according to refractive status: myopia (spherical equivalent [SE] ≤ -1.0 diopter [D]), emmetropia (-1.0 D < SE ≤ 1.0 D), and hyperopia (SE > 1.0 D). Obesity was investigated with assessment of fat mass and body mass index or waist circumference. Fat mass was measured with whole-body dual energy x-ray absorptiometry. Body fat percentage was calculated as (total fat mass / body weight × 100). RESULTS: Higher obesity index was found in individuals with myopic eyes after adjustment for age, sex, education level, income status, physical activity, residence, and serum vitamin D level. The significant difference in total body fat percentages among myopia, emmetropia, and hyperopia was significant in the young age group (19-39 years, p < 0.05) but not in the middle age group (40-64 years) and the old age group (≥65 years). Individuals with a higher percentage of total body fat had greater odds ratios for myopia (fourth quartile of body fat; odds ratio, 1.352; 95% confidence interval, 1.178-1.551). CONCLUSIONS: An association was found between adiposity and myopia in relatively young adults using direct measurements of fat mass.

Prevalence and risk factors for astigmatism in 7 to 19-year-old students in Xinjiang, China: a cross-sectional study.

BACKGROUND: To investigate the prevalence and risk factors for astigmatism in 7-19-year-old students in Xinjiang, China. METHODS: A school-based, cross-sectional study was conducted on students who underwent refraction examination in Xinjiang, China, between May and December 2019. The prevalence of astigmatism was determined. Astigmatism was defined as cylinder power (C) ≤-0.75 D, undefined astigmatism as ≤-1.50 D, and high astigmatism as C ≤-3.00 D. Astigmatism types were: against-the-rule astigmatism (maximum refraction of the main meridian in 180° ± 30°), with-the-rule astigmatism (maximum refraction of the main meridian at 90°±30°), and oblique astigmatism (all other cases). RESULTS: Of the 71,838 students examined (51.0% boys, 7 - 19 years old), 25,945 (36.1%, 95%CI: 35.52-36.68%) had astigmatism and 1267 (1.8%, 95%CI: 1.07-2.53%) had high astigmatism. The prevalence of astigmatism was greater in Han individuals (39.6%) compared with the Hui (34.0%), Kazakh (34.0%), Kyrgyz (32.1%), and Uyghur (26.4%) populations. Among the 25,945 students with astigmatism, 19,947 had with-the-rule astigmatism (76.9%), 3405 had against-the-rule astigmatism (13.1%), and 2593 had oblique astigmatism (10.0%). Multivariable logistic regression analysis showed that ethnicity (Han individuals more susceptible), male gender, age, and refractive errors (myopia and hyperopia) were independently associated with astigmatism, high astigmatism, and with-the-rule astigmatism (all P < 0.05). CONCLUSIONS: The prevalence of astigmatism among children and adolescents in Xinjiang was 36.1%, including 1.8% of high astigmatism. In this population, astigmatism was mainly of the with-the-rule astigmatism type (76.9%). Han ethnicity, male gender, and myopia or hyperopia were independently associated with a high risk of astigmatism.

Assessment of the effects of myopic and hyperopic anisometropia on choroidal vascular structure in children using SS-OCTA.

OBJECTIVE: To compare large- and medium-sized choroidal vascularity and the choriocapillaris (CC) flow area in children with different refractive errors using swept-source optical coherence tomography angiography (SS-OCTA). METHODS: Forty-two anisometropic children were enrolled and divided into hyperopic anisometropia (HA) and myopic anisometropia (MA) groups. SS-OCTA was performed to analyse choroidal vascularity. Mean choroidal thickness (CT), choroidal vascularity volume (CVV), choroidal vascularity index (CVI) and CC flow area were compared between the two eyes. The inter-ocular differences between the two groups were also determined. RESULTS: Mean CT and CVV were highest in eyes with shorter axial lengths in both refractive groups, and the difference between the two eyes was positively correlated with the difference in axial length at the foveal region. Significant differences in the CVI in the MA group were only found in the parafoveal region. Inter-ocular differences in the CC were significantly reduced in eyes with longer axial lengths in the foveal and parafoveal regions of the HA and MA groups, respectively. Comparing inter-ocular differences, CC was significantly greater in the parafoveal region of the MA group than the HA group. CONCLUSIONS: All layers of choroidal vasculature were thinner in eyes with longer axial lengths in all groups. The inter-ocular CC difference was greater in the MA than in the HA group, with similar differences in axial length. This suggests that both medium-to-large choroidal vascular and choroidal capillaries may play a role in myopia development.

Detection of significant vision conditions in children using QuickSee wavefront autorefractor.

PURPOSE: This study evaluated the ability of QuickSee to detect children at risk for significant vision conditions (significant refractive error [RE], amblyopia and strabismus). METHODS: Non-cycloplegic refraction (using QuickSee without and with +2 dioptre (D) fogging lenses) and unaided binocular near visual acuity (VA) were measured in 4- to 12-year-old children. Eye examination findings (VA, cover testing and cycloplegic retinoscopy) were used to determine the presence of vision conditions. QuickSee performance was summarised by area under the receiver operating characteristic curve (AUC), sensitivity and specificity for various levels of RE. QuickSee referral criteria for each vision condition were chosen to maximise sensitivity at a specificity of approximately 85%-90%. Sensitivity and specificity to detect vision conditions were calculated using multiple criteria. Logistic regression was used to evaluate the benefit of adding near VA (6/12 or worse) for detecting hyperopia. A paired t-test compared QuickSee without and with fogging lenses. RESULTS: The mean age was 8.2 (±2.5) years (n = 174). RE ranged up to 9.25 D myopia, 8 D hyperopia, 5.25 D astigmatism and 3.5 D anisometropia. The testability of the QuickSee was 94.3%. AUC was ≥0.92 (excellent) for each level of RE. For the detection of any RE, sensitivity and specificity were 84.2% and 87.3%, respectively, using modified Orinda criteria and 94.5% and 78.2%, respectively, using the American Academy for Pediatric Ophthalmology and Strabismus (AAPOS) guidelines. For the detection of any significant vision condition, the sensitivity and specificity of QuickSee were 81.1% and 87.9%, respectively, using modified Orinda criteria and 93% and 78.6%, respectively, using AAPOS criteria. There was no significant benefit of adding near VA to QuickSee for the detection of hyperopia ≥+2.00 (p = 0.34). There was no significant difference between QuickSee measurements of hyperopic refractive error with and without fogging lenses (difference = -0.09 D; p = 0.51). CONCLUSIONS: QuickSee had high discriminatory power for detecting children with hyperopia, myopia, astigmatism, anisometropia, any significant refractive error or any significant vision condition.

Improving the accuracy of the SRK/T formula in Chinese with implanting less than 10 D IOL calculated by the SRK/T formula: the SRK/T-Li formula.

PURPOSE: To explore the accuracy of the improved SRK/T-Li formula in eyes following implantation of intraocular lens (IOL) of less than 10 D as calculated by using the SRK/T formula in Chinese. METHODS: A total of 489 eyes from 489 patients with cataracts were included in this study. These patients were divided into a training set (271 patients) and a testing set (218 patients). The IOL power calculated by using SRK/T was less than 10 D. We evaluated the accuracy of the modified SRK/T-Li formula (P = PSRK/T × 0.8 + 2 (P = implanted IOL power; PSRK/T = IOL power calculated by SRK/T)). We evaluated the mean absolute error (MAE), percentage of prediction error (PE) within ± 0.25, ± 0.50, and ± 1.00 D, and the percentage of postoperative hyperopia. RESULTS: The MAE values in order of lowest to highest were as follows: 0.412 D (SRK/T-Li), 0.414 D (Barrett Universal II, (BUII)), 0.814 D (SRK/T), and 1.039 D (Holladay 1). The percentage of PE within ± 0.25 D, ± 0.50 D, and ± 1.00 D was 38.99%, 69.27% and 92.66% (BUII), 40.83%, 69.27% and 94.04% (SRK/T-Li), 20.64%, 41.28% and 71.56% (SRK/T), and 7.34%, 16.51% and 53.21% (Holladay 1), respectively. SRK/T-Li had the smallest postoperative hyperopic shift. CONCLUSIONS: For Chinese patients with an IOL power of less than 10 D as calculated by using the SRK/T, the SRK/T-Li has good accuracy and is the best choice to reduce postoperative hyperopic shift.

Using big data to understand interest in myopia.

SIGNIFICANCE: Popularity of publicly searched myopia terminologies is reported, for example, myopia control over myopia management and myopia over nearsighted or shortsighted. Insights are also provided for searches on specific myopia control interventions. The findings offer an evidence-based starting point for public messaging and communications by clinicians, policymakers, and other industry leaders. PURPOSE: Public understanding of myopia can be difficult to ascertain for clinicians. Although small-scale studies provide valuable snapshots of data, findings tend to be population-specific and thus difficult to extrapolate to global audiences. In this study, big data were used to provide a more comprehensive depiction of global market interest in myopia. METHODS: Google Trends data were used to analyze searches relating to myopia between January 2004 and August 2023. Data extracted were related to use of the terms myopia control and myopia management, with further searches executed for common myopia control interventions: orthokeratology, contact lenses, atropine, and glasses. Analysis into the search interest of other refractive error states, hyperopia and astigmatism, was also undertaken along with alternative terms that may be used to describe myopia. Where relevant, search trends were considered worldwide, by country, and over time. RESULTS: Myopia was a more popular search term than common layman alternatives such as nearsighted or shortsighted. Myopia control was found to be more popular than myopia management, and of the specific myopia interventions, atropine was most popular. Compared with astigmatism and hyperopia, relative search volumes were greatest for myopia, on average accounting for approximately 50% of the relative search volume at the country level. CONCLUSIONS: The differences identified in both popularity of myopia-related search terms and specific interventions may provide the basis for improvements in public messaging and facilitate patient-practitioner communication.

Prevalence of Keratoconus Based on Scheimpflug Corneal Tomography Metrics in a Pediatric Population From a Chicago-Based School Age Vision Clinic.

PURPOSE: Determine the pediatric prevalence of keratoconus (KC) using Scheimpflug corneal tomography. METHODS: A prospective observational study was done on subjects aged 3 to 18 years at the Princeton Vision Clinic, Chicago, IL. Scheimpflug tomography (Pentacam HR, OCULUS Optikgerate GmbH) scans (Belin/Ambrósio Enhanced Ectasia BAD3) yielded BAD Final D (Final D) and Back Elevation at the Thinnest Point (BETP) measurements. Criteria differentiating non-KC from KC suspects & KC were, Non-KC -Final D <2.00 in both eyes; KC suspect -Final D ≥2.00 and <3.00 in combination with BETP ≥18 µm for myopia and ≥28 µm for hyperopia/mixed astigmatism in at least one eye; and KC -Final D of ≥3.00 with BETP ≥18 µm for myopia or ≥28 µm for hyperopia/mixed astigmatism in at least one eye. Two thousand two hundred and six subjects were recorded, removing duplicate and poor-quality scans leaving 2007 subjects. RESULTS: Of 2007 subjects, six were classified as KC -prevalence of 1:334, three subjects were KC suspects -prevalence of 1:669, and total prevalence of KC suspects and KC was 1:223. CONCLUSION: The prevalence of KC in children is higher than previously reported, emphasizing the importance of sensitive screening for KC at its earliest manifestation as standard in pediatric comprehensive eye examinations.

Subjective versus objective refraction in healthy young adults.

PURPOSE: To evaluate objective and subjective refraction differences in healthy young adults. METHODS: Data concerning candidates for the Israeli Air Force Flight Academy, as well as active air force pilots in all stages of service who underwent a routine health checkup between the years 2018 and 2019 were retrospectively analyzed. Objective refraction measured using a single autorefractometer was compared with subjective refraction measured by an experienced military optometrist during the same visit. The results were converted to power vectors (spherical equivalent [SE], J0, and J45). To interpret astigmatism using power vector values, the cylinder power (Cp) was determined. RESULTS: This study included 1,395 young adult participants. The average age was 22.17 years (range, 17-39, 84.8% males). The average SE was - 0.65 ± 1.19 diopter (D) compared with - 0.71 ± 0.91D in the auto- and subjective refraction, respectively (p = 0.001). Cp was 0.91 ± 0.52D and 0.67 ± 0.40D, respectively (p < 0.001). This difference was more common in older participants (p < 0.001). J0 and J45 value differences were not significant. The absolute SE value of subjective refraction was lower in the myopic (p < 0.001) and hyperopic (p < 0.001) patients. CONCLUSIONS: Young hyperopic participants tended to prefer "less plus" in subjective refraction compared with autorefraction. Young myopic participants tended to prefer "less minus" in subjective refraction compared with autorefraction. All participants, but mainly older participants, preferred slightly "less Cp" than that measured using autorefraction; The astigmatic axis did not differ significantly between the methods.

Refractive error and vision related quality of life.

BACKGROUND: To investigate and compare the vision-related quality of life (QOL) in different types of refractive error (RE). METHODS: This cross-sectional study was performed on 200 subjects, categorized into four groups of 50 each, consisting of subjects with myopia, hyperopia, astigmatism, and emmetropia, the latter being the control group. The mean age of the participants was 23.88 ± 5.87 (range, 15 to 38: 110 females and 90 males). RE was defined as myopia, spherical equivalent (SE) < -0.25 diopters (D), hyperopia, SE > + 0.25 D, astigmatism, cylinder < -0.25 D, and emmetropia (-0.25 ≤ SE(D) ≤ + 0.25, cylinder ≥ -0.25). Groups are subdivided into very low magnitudes of RE (0.50 and 0.75) and significant RE (1.00 ≤). Vision-related QOL was assessed using the Persian version of the 25-item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25). The NEI-VFQ was scored as visual function and socioemotional scales using Rasch analysis. RESULTS: Corrected myopia, astigmatism, uncorrected myopia, and hyperopia had a lower vision-related QOL than emmetropes. (P < 0.001). Vision-related QOL in myopic subjects was lower than that in astigmatic participants. Very low myopes, who often do not use correction, had a significantly lower QOL than other groups. CONCLUSION: Individuals with refractive errors experience a lower QOL score than those without. Notably, the adverse impact on QOL score is significantly greater in myopic cases, particularly very low myopia, compared to other refractive errors. Therefore, it is strongly recommended not to neglect managing very low myopia since it may improve participants' QOL.

Causal associations of refractive error and early age-related macular degeneration: A Mendelian randomization study.

This study aims to determine the risk associated with early age-related macular degeneration (AMD) due to refractive errors (RE) using an analysis of genome-wide association study (GWAS) data through the two-sample Mendelian randomization approach. Single-nucleotide polymorphisms (SNPs) linked to refractive errors (RE) were obtained from numerous GWAS studies involving individuals of European descent. The data for early AMD was obtained from a diverse, multiethnic GWAS meta-analysis that included 105,248 participants (14,034 cases and 91,214 controls). The primary outcome measure focused on the rise in early AMD risk corresponding to a 1-diopter alteration in spherical power and cylindrical power. In the main Mendelian randomization analysis, inverse-variance weighting (IVW) methods were applied for the evaluation. Mendelian Randomization (MR) study revealed a substantial impact of refractive error (RE) on early AMD risk, with a 1-diopter increase in hypermetropia being related to a 1.16 odds ratio (OR) for a greater risk of early AMD (95% CI, 1.10-1.23; P < 0.01). This conclusion was further supported by four supplementary approaches, namely, Weighted mode, Weighted-median, Simple mode, and MR-Egger. The results suggest a heightened risk of early AMD correlated with hyperopia, necessitating further research to thoroughly elucidate this potential causal relationship.

Factors Predicting Slow Visual Recovery Following Hyperopic LASIK.

PURPOSE: To identify factors predicting slow visual recovery following hyperopic laser in situ keratomileusis (LASIK). METHODS: The study included consecutive patients who underwent hyperopic LASIK between January 2005 and December 2019 at a single medical center. Patients were divided into two groups according to whether they experienced normal recovery of visual acuity (1-week visit) or slow visual recovery (1-month visit). Visual recovery was defined as achieving an efficacy index of 0.9 or greater. Efficacy index was calculated as postoperative uncorrected distance visual acuity / preoperative corrected distance visual acuity. A comparison of baseline and intraoperative parameters was performed. Binary logistic regression was performed to identify potential predictors of slow visual recovery. RESULTS: Overall, 861 eyes of 861 patients were included. Mean age was 48.0 ± 9.5 years and 55.9% were women. Two hundred forty-nine patients (28.9%) experienced slow visual recovery. Younger age (P = .01), a larger preoperative spherical equivalence (P = .002), and greater maximum ablation depth (P = .002) were predictors of slow visual recovery. In binary logistic regression, female gender (P = .036) and greater spherical equivalence (P = .007) remained significant predictors of slow visual recovery. CONCLUSIONS: Female gender and greater preoperative spherical equivalence were associated with slow visual recovery. Patients may be advised accordingly. [J Refract Surg. 2024;40(1):e42-e47.].

Factors Predicting Slow Visual Recovery Following Hyperopic LASIK.

PURPOSE: To identify factors predicting slow visual recovery following hyperopic laser in situ keratomileusis (LASIK). METHODS: The study included consecutive patients who underwent hyperopic LASIK between January 2005 and December 2019 at a single medical center. Patients were divided into two groups according to whether they experienced normal recovery of visual acuity (1-week visit) or slow visual recovery (1-month visit). Visual recovery was defined as achieving an efficacy index of 0.9 or greater. Efficacy index was calculated as postoperative uncorrected distance visual acuity / preoperative corrected distance visual acuity. A comparison of baseline and intraoperative parameters was performed. Binary logistic regression was performed to identify potential predictors of slow visual recovery. RESULTS: Overall, 861 eyes of 861 patients were included. Mean age was 48.0 ± 9.5 years and 55.9% were women. Two hundred forty-nine patients (28.9%) experienced slow visual recovery. Younger age (P = .01), a larger preoperative spherical equivalence (P = .002), and greater maximum ablation depth (P = .002) were predictors of slow visual recovery. In binary logistic regression, female gender (P = .036) and greater spherical equivalence (P = .007) remained significant predictors of slow visual recovery. CONCLUSIONS: Female gender and greater preoperative spherical equivalence were associated with slow visual recovery. Patients may be advised accordingly. [J Refract Surg. 2024;40(1):e42-e47.].

Influence of the patient's age on the safety, efficacy, and prediction accuracy of the microkeratome in laser-assisted in situ keratomileusis.

The purpose of this retrospective pseudonymised data analysis was to determine whether the patient's age has an influence on the safety, efficacy, and prediction accuracy of laser in situ keratomileusis (LASIK) treatment of myopic and hyperopic eyes. This study was performed at CARE Vision GmbH (Düsseldorf, Germany) and included two patient cohorts: an older group with patients > 55 years old and a younger group with patients 30-40 years old. Each patient had a single LASIK treatment. The safety, efficacy, and prediction accuracy of the refractive results were analysed. In total, 682 patients were analysed, with 341 patients in each patient group (one eye per patient). There were 570 myopic eyes and 112 hyperopic eyes. In myopic eyes, the efficacy was significantly influenced by the patient's age but only in myopic eyes (myopic: p ≤ 0.05; hyperopic: p = 0.085), while safety was not significantly influenced by the patient's age in hyperopic or myopic eyes (p = 0.204). We found that LASIK treatment at an older age (> 55 years) resulted in almost the same safety outcomes as a LASIK treatment at a younger age (30-40 years) but with a lower efficacy; the efficacy correlated with the patient's age. If the patient was hyperopic, their age did not influence safety or efficacy.

The association between iris color and refractive errors in children.

This study aimed to evaluate the association between iris color and refractive errors in children aged 6-12 years. This cross-sectional study was based on data obtained from the first phase of the Shahroud Schoolchildren Eye Cohort Study. The target population was 6 to12 year-old students living in urban and rural areas. Iris colors were classified by comparing eye colors with close-up images of iris colors. Myopia was defined as a spherical equivalent (SE) ≤ - 0.5 diopter and hyperopia was defined as SE ≥ 2 diopter in cycloplegic refraction. The association of iris color with hyperopia and myopia was investigated by fitting two separate multiple logistic regression models adjusted for place of residence, age, sex, and times for outdoor activity and near work. Among the 5394 participates with the mean age of 9.7 year, the prevalence of myopia and hyperopia was 4.8% and 4.7% respectively. The number and proportion (in parentheses) of amber, light blue, light brown, dark brown, gray, green and hazel iris colors were 19(0.4%), 26(0.5%), 645(12.0%), 4517(83.7%), 4(0.1%), 59(1.1%), and 124(2.3%) respectively. Compared to dark brown, the odds ratios and 95% confidence intervals (in parentheses) of myopia were 4.8(1.2-18.7), 0.8(0.1-5.8), 1.0(0.7-1.5), 0.4(0.1-2.7) and 0.6(0.2-1.8) for amber, light blue, light brown, green and hazel iris colors in multiple logistic regression model. No significant association was observed between iris colors and hyperopia. This study shows that amber iris is significantly associated with higher odds of myopia. These children should be further monitored and examined. More studies with higher sample size in all iris colors are recommended.

Lens power, cornea power and association with refractive error in children with moderate to high hyperopia.

OBJECTIVE: This study aimed to profile ocular biometry parameters and predictors of spherical equivalent refraction (SER) among children with moderate to high hyperopia. METHODS: Individuals <18 years of age with moderate to high hyperopia were enrolled from November 2015 to November 2021. Participants underwent a series of comprehensive ocular examinations, and were classified as having low hyperopia, that is, SER +0.5 to < +2.0 D or moderate to high hyperopia, that is, SER ≥ +2.0 D. RESULTS: A total of 459 and 230 eyes with moderate to high hyperopia and low hyperopia, respectively, were included. Moderate to high hyperopic eyes had a shorter axial length, stronger lens power (24.78 ± 5.47 D vs. 18.74 ± 1.63 D, p < 0.001) and weaker corneal power (42.82 ± 1.75 D vs. 43.31 ± 1.55 D, p < 0.001) than low hyperopic eyes. When comparing values before and after 5 years of age, both lens power and axial length differed significantly in the moderate to high hyperopia group, whereas in the low hyperopia group, they only differed significantly after 9 years of age. Lens power was negatively associated with AL in eyes with axial lengths between 20 and 22 mm. A multiple linear regression model which included axial length (standardised ß = -0.80, p < 0.001), corneal power (standardised ß = -0.47, p < 0.001) and lens power (standardised ß = 0.23, p < 0.001) explained 81.2% of the variance in SER. CONCLUSIONS: Differences in lens power and axial length in moderate to high hyperopic eyes became significantly smaller after 5 years of age, at least 4 years earlier than for the low hyperopia. Lens power could offset the axial elongation in participants with axial lengths between 20 and 22 mm, suggesting that children with moderate to high hyperopia might have different ocular growth patterns. Axial length, corneal power and lens power were the main predictors of SER in moderate to high hyperopia.

Epithelial thickness remodeling after small incision lenticule intrastromal keratoplasty in correcting hyperopia measured by RTVue OCT.

PURPOSE: To characterize the in vivo corneal epithelial thickness (CET) remodeling profile in a population of eyes after small incision lenticule intrastromal keratoplasty (SMI-LIKE) for hyperopia. METHODS: The CET profile was measured by RTVue-100 Fourier-domain OCT system across the central 6-mm diameter of the cornea of 17 eyes from 12 subjects (five males and seven females) who accepted corneal stromal lens implantation surgery for correcting hyperopia. The CET were measured at positions with a radius of 0-1.0 mm, 1.0-2.5 mm (divided into eight quadrants) and 2.5-3.0 mm (divided into eight quadrants) from the corneal center. Corneal maximum simulated keratometry (Km) was measured by Pentacam HR anterior segment analyzer to analyze CET changes. The examination data of subjects were collected in four time periods, which were preoperative, short-term postoperative (one week after surgery), mid-term postoperative (the last review within 3-6 months after surgery), and long-term postoperative (the last review over 1-2.5 years after surgery). The changes of CET were compared and analyzed in the four time periods. RESULTS: Mean CET in 0-1.0 mm, 1.0-2.5 mm and 2.5-3.0 mm of the cornea decreased in one week after surgery, respectively, as compared to CET in the preoperative period, which turned from 55.06 ± 0.82 µm、54.42 ± 0.75 µm、53.46 ± 0.60 µm to 51.18 ± 1.05 µm (P = 0.005), 49.38 ± 0.70 µm (P = 0.000), 51.29 ± 0.59 µm (P = 0.025). In the mid-term postoperative period, mean CET in 0-1.0 mm and 1.0-2.5 mm areas kept thinner than mean CET in the preoperative period, CET in 0-1.0 mm is 50.59 ± 0.76 µm (P = 0.000),CET in 1.0-2.5 mm is 50.23 ± 0.57 µm (P = 0.000), while mean CET in 2.5-3.0 mm area recovered to the same thickness as the preoperative level, which is 54.36 ± 0.66 µm (P = 1.000), until the long-term period, CET stabilized in the above doughnut pattern. CONCLUSIONS: After stromal lenticule implantation for hyperopia, CET showed a remodeled form of thinning in the 0-2.5 mm area and thickening in the 2.5-3.0 mm area, and remained stable within one year after surgery.

Artificial intelligence enhanced ophthalmological screening in children: insights from a cohort study in Lubelskie Voivodeship.

This study aims to investigate the prevalence of visual impairments, such as myopia, hyperopia, and astigmatism, among school-age children (7-9 years) in Lubelskie Voivodeship (Republic of Poland) and apply artificial intelligence (AI) in the detection of severe ocular diseases. A total of 1049 participants (1.7% of the total child population in the region) were examined through a combination of standardized visual acuity tests, autorefraction, and assessment of fundus images by a convolutional neural network (CNN) model. The results from this artificial intelligence (AI) model were juxtaposed with assessments conducted by two experienced ophthalmologists to gauge the model's accuracy. The results demonstrated myopia, hyperopia, and astigmatism prevalences of 3.7%, 16.9%, and 7.8%, respectively, with myopia showing a significant age-related increase and hyperopia decreasing with age. The AI model performance was evaluated using the Dice coefficient, reaching 93.3%, indicating that the CNN model was highly accurate. The study underscores the utility of AI in the early detection and diagnosis of severe ocular diseases, providing a foundation for future research to improve paediatric ophthalmic screening and treatment outcomes.