Phase-contrast visualization of human tissues using superimposed wavefront imaging of diffraction-enhanced x-rays.

BACKGROUND: Phase-contrast computed tomography (CT) using high-brilliance, synchrotron-generated x-rays enable three-dimensional (3D) visualization of microanatomical structures within biological specimens, offering exceptionally high-contrast images of soft tissues. Traditional methods for phase-contrast CT; however, necessitate a gap between the subject and the x-ray camera, compromising spatial resolution due to penumbral blurring. Our newly developed technique, Superimposed Wavefront Imaging of Diffraction-enhanced x-rays (SWIDeX), leverages a Laue-case Si angle analyzer affixed to a scintillator to convert x-rays to visible light, capturing second-order differential phase contrast images and effectively eliminating the distance to the x-ray camera. This innovation achieves superior spatial resolution over conventional methods. PURPOSE: In this paper, the imaging principle and CT reconstruction algorithm based on SWIDeX are presented in detail and compared with conventional analyzer-based imaging (ABI). It also shows the physical setup of SWIDeX that provides the resolution preserving second-order differential images for reconstruction. We compare the spatial resolution and the sensitivity of SWIDeX to conventional ABI. METHODS: To demonstrate high-spatial resolution achievable by SWIDeX, the internal structures of four human tissues-ductal carcinoma in situ, normal stomach, normal pancreas, and intraductal papillary mucinous neoplasm of the pancreas-were visualized using an imaging system configured at the Photon Factory's BL14B beamline under the High Energy Accelerator Research Organization (KEK). Each tissue was thinly sliced after imaging, stained with hematoxylin and eosin (H&E) for conventional microscope-based pathology. RESULTS: A comparison of SWIDeX-CT and pathological images visually demonstrates the effectiveness of SWIDeX-CT for biological tissue imaging. SWIDeX could generate clearer 3D images than existing analyzer-based phase-contrast methods and accurately delineate tissue structures, as validated against histopathological images. CONCLUSIONS: SWIDeX can visualize important 3D structures in biological soft tissue with high spatial resolution and can be an important tool for providing information between the disparate scales of clinical and pathological imaging.

The significance of growth shells in development of symmetry, transparency, and refraction of the human lens.

Human visual function depends on the biological lens, a biconvex optical element formed by coordinated, synchronous generation of growth shells produced from ordered cells at the lens equator, the distal edge of the epithelium. Growth shells are comprised of straight (St) and S-shaped (SSh) lens fibers organized in highly symmetric, sinusoidal pattern which optimizes both the refractile, transparent structure and the unique microcirculation that regulates hydration and nutrition over the lifetime of an individual. The fiber cells are characterized by diversity in composition and age. All fiber cells remain interconnected in their growth shells throughout the life of the adult lens. As an optical element, cellular differentiation is constrained by the physical properties of light and its special development accounts for its characteristic symmetry, gradient of refractive index (GRIN), short range transparent order (SRO), and functional longevity. The complex sinusoidal structure is the basis for the lens microcirculation required for the establishment and maintenance of image formation.

Intraoperative OCT to check the correct postimplant position of PreserfloTM.

INTRODUCTION: This study was designed to examine the capacity of intraoperative optical coherence tomography (OCT) to predict the postimplant position of the glaucoma drainage device PreserfloTM. METHODS: 13 eyes (mean age 65.42 (14.89) years) underwent PreserfloTM (Santen, Osaka, Japan) placement. Before surgery, participants were subjected to a comprehensive ophthalmic examination (intraocular pressure (IOP), cup to disk ratio (C/D), visual field, OCT, endothelial cell count). Anterior segment OCT scans were obtained intraoperatively using a Rescan 700 OCT system (Carl Zeiss Meditec, Inc., Oberkochen, Germany). One day postsurgery, anterior segment OCT using the Spectralis OCT (Heidelberg Engineering GmbH) was performed in a sitting position to capture the same chamber cross-section as before. The main outcome variables were tube-endothelium distance (T-E) and tube length (TL) in the anterior chamber measured using both OCT systems. Correlation between intraoperative and office measurements was examined through Pearson correlation (r) and intraclass correlation coefficients (ICC). RESULTS: Mean intraoperative and in-office T-E were 625.26 (SD 366.60) versus 561.16 (SD 364.62) µm respectively (p = 0.540). Intraoperative and in-office anterior chamber TL were 1386 (SD 701.82) and 1433.91 (SD 713.55) µm, respectively (p = 0.029). Excellent correlation was observed between both sets of T-E (r = 0.992; p = 0.008) and TL (r = 0.984; p = 0.016) values. Both OCT systems showed good agreement yielding ICCs of 0.992 (p < 0.001) for T-E and 0.995 (p = 0.001) for TL. DISCUSSION: Excellent correlation was observed between our intraoperative and postoperative OCT measurements. These results support the usefulness of intraoperative OCT to confirm the correct position of an implanted PreserfloTM microshunt.

IOL decentration sensitivity according to spatial frequencies.

BACKGROUND/AIMS: Investigation of the decentration sensitivity of monofocal intraocular implants with a focus on different aberration corrections depending on different spatial frequencies. METHODS: Using an optical bench, the decentration sensitivities of an intraocular lens (IOL) with a high spherical aberration correction of -0.27 µm (ZCB00 Johnson & Johnson), an IOL with an aberration correction of -0.20 µm (Primus HD OphthalmoPro) and an IOL with an aberration neutral design (CT Asphina 409MP Carl Zeiss Meditec) were evaluated for Strehl ratio values and for 25, 50 and 100 lp/mm. Two different corneas with +0.13 µm and +0.28 µm were used. The lenses were tested in the best centration and up to a decentration of 0.5 mm. RESULTS: Decentration sensitivity affects high spatial frequencies more than lower ones. The possible decentration sensitivity is determined by the amount of spherical aberration of the cornea. The effective decentration sensitivity is determined by the extent to which these spherical aberrations are compensated. If these are not compensated, there is hardly any decentration sensitivity. CONCLUSION: High spatial frequencies are more affected by decentration sensitivity. The decentration sensitivity of an IOL is determined by the extent to which the spherical aberration of the cornea is corrected.

A clearer vision: unveiling the importance of cycloplegic refraction and the pseudomyopia prevalence in Chinese preschoolers.

BACKGROUND: This study aimed to investigate the difference between cycloplegic and noncycloplegic refraction and evaluate the pseudomyopia prevalence in Chinese preschool children during the outbreak of COVID-19. METHODS: A cross-sectional study was conducted in the Tongzhou District of Beijing, China. Refractive error was measured under both noncycloplegic and cycloplegic conditions with autorefraction. The difference between noncycloplegic and cycloplegic spherical equivalent refraction (SER) and pseudomyopia prevalence were analyzed. Pseudomyopia was defined as SER ≤-0.50D in precycloplegic assessments and >-0.50D in post-cycloplegic assessments. RESULTS: Out of the 1487 participants who were enrolled in the study, 1471 individuals (98.92%) between the ages of 3-6 years completed all required procedures. A statistically significant difference in refraction was observed between noncycloplegic and cycloplegic measurements, the median of difference in spherical equivalent refraction (SER) of 0.88D (dioptre)(0.50,1.38). There was a high intraclass correlation (ICC) between these two methods for cylinders (ICC = 0.864; 95% CI, 0.850-0.877). The median DSE for myopia, emmetropia and hyperopia were 0.25D (0.00, 0.38),0.25D (0.06, 0.50) and 1.00D (0.62, 1.38), an hypermetropes showed considerably greater differences than myopes and emmetropes (Kruskal-Wallis test, H = 231.023, P = 0.000). Additionally, girls displayed a greater DSE than boys. Furthermore, when comparing against-the-rule (ATR) and oblique astigmatism, it was found that with-the-rule (WTR) astigmatism had the largest DSE. The study found varying prevalence rates of myopia, emmetropia, and hyperopia with and without cycloplegia, which were 1.90% vs. 10.06%, 11.49% vs. 50.31%, and 86.61% vs. 39.63%, respectively. Additionally, the overall prevalence of pseudomyopia was determined to be 8.29%. Participants with pseudomyopia had a significantly higher mean difference in SER (DSE) compared to non-pseudomyopic participants. CONCLUSIONS: Cycloplegic refraction is more sensitive than a noncycloplegic one for measuring refractive error in preschool children. Pseudomyopia is prevalent in preschool children during the COVID-19 outbreak period. Our study indicates the possibility that cycloplegic refraction should be performed in preschool children routinely.

Macular thickness and visual acuity are characterized by a quadratic nonlinear relation in previously treated neovascular AMD eyes.

PURPOSE: To assess the associations between visual acuity (VA) and retinal thickness in age-related macular degeneration (AMD) eyes treated with anti-vascular endothelial growth factor (VEGF) therapy. METHODS: Sixty-eight patients with neovascular AMD (68 eyes) undergoing anti-VEGF therapy with two years of follow-up imaging data after the initiation of treatment were retrospectively included. Linear and nonlinear regression analyses with curve fitting estimation were performed to explore the relationship between visual acuity and OCT-based parameters at the 3-month and 24-month follow-up visits. Regression analyses were also performed between visual acuity and the retinal thickness deviation which was calculated as the absolute value of the difference between measured and normative retinal thickness values. RESULTS: The VA was not associated with either foveal (R2 = 0.011 and p = .401 at 3 months; R2 = 0.032 and p = .142 at 24 months) or parafoveal (R2 = 0.045 and p = .081 at 3 months; R2 = 0.050 and p = .055 at 24 months) retinal thicknesses. Compared with the linear models, a quadratic function yielded a relative increase in the R2 coefficients. Conversely, the VA was linearly associated with foveal retinal thickness deviation (R2 = 0.041 and p = .037 at 24 months) and parafoveal retinal thickness deviation (R2 = 0.062 and p = .040 at 3 months; R2 = 0.088 and p = .014 at 24 months) values. CONCLUSIONS: Although there was no linear relationship between retinal thickness and VA, a weak but statistically significant linear relationship could be observed when a retinal thickness deviation was considered. This suggests that deviation-based parameters may be beneficial for structure-function correlations in the context of anti-VEGF therapy for neovascular AMD.

Sources of reduced visual acuity and spectacle treatment options for individuals with Down syndrome: Review of current literature.

Individuals with Down syndrome are known to have a greater prevalence of ocular conditions such as strabismus, nystagmus, elevated refractive error, poor accommodative function, elevated higher-order optical aberrations and corneal abnormalities. Related to these conditions, individuals with Down syndrome commonly have reduced best-corrected visual acuity at both far and near viewing distances across their lifespan. This review summarises the various optical sources of visual acuity reduction in this population and describes clinical trials that have evaluated alternative spectacle prescribing strategies to minimise these optical deficits. Although refractive corrections may still have limitations in their ability to normalise visual acuity for individuals with Down syndrome, the current literature provides evidence for eye care practitioners to consider in their prescribing practices for this population to maximise visual acuity. These considerations include accounting for the presence of elevated higher-order aberrations when determining refractive corrections and considering bifocal lens prescriptions, even for young children with Down syndrome.

Determination of the time of refractive stability after uneventful phacoemulsification in Indian eyes.

BACKGROUND: Knowledge about refractive stabilization and the accuracy of postoperative refractive error measurements are crucial for improved patient outcomes after phacoemulsification. Existing guidelines typically recommend waiting 4-6 wk before prescribing corrective lenses. Our research focused on identifying factors that influence refractive errors in the early stages of post-cataract surgery, thus contributing to the existing literature on this topic. AIM: To investigate the time required for refraction stability after uneventful phacoemulsification surgery. METHODS: We compared the variation and statistical significance of the difference in spherical, cylindrical components, and the spherical equivalent between the 1- and 6-wk follow-up period in a group of 257 eyes that underwent uneventful phacoemulsification with foldable intraocular lens implantation, all performed by a single experienced surgeon. The Wilcoxon-Signed Rank Test was utilized to assess the magnitude of the change and determine its statistical significance. The refractive stability was defined as the point at which the change in spherical equivalent was within ± 0.5 dioptres for two consecutive visits. RESULTS: The average age of the patients was 64.9 ± 8.9 yr. The differences observed in both the visits in spherical power (0.1 ± 0.2), cylinder power (0.3 ± 0.4), and spherical equivalent (0.2 ± 0.2) were minimal and not statistically significant. The majority of eyes (93.4%) achieved refractive stability within 6 wk after the surgery. The cylindrical power differed between age groups at the 6th wk post-operative and the difference was statistically significant (P value 0.013). There were no significant differences in refractive stability when considering sex and axial length. CONCLUSION: Phacoemulsification with foldable intraocular lens implantation results in no significant changes in refraction for the majority of cases during the 6-wk follow-up period. Therefore, a spectacle prescription can be given at the completion of 1 wk.

Quantitative assessment of colour fundus photography in hyperopia children based on artificial intelligence.

OBJECTIVES: This study aimed to quantitatively evaluate optic nerve head and retinal vascular parameters in children with hyperopia in relation to age and spherical equivalent refraction (SER) using artificial intelligence (AI)-based analysis of colour fundus photographs (CFP). METHODS AND ANALYSIS: This cross-sectional study included 324 children with hyperopia aged 3-12 years. Participants were divided into low hyperopia (SER+0.5 D to+2.0 D) and moderate-to-high hyperopia (SER≥+2.0 D) groups. Fundus parameters, such as optic disc area and mean vessel diameter, were automatically and quantitatively detected using AI. Significant variables (p<0.05) in the univariate analysis were included in a stepwise multiple linear regression. RESULTS: Overall, 324 children were included, 172 with low and 152 with moderate-to-high hyperopia. The median optic disc area and vessel diameter were 1.42 mm2 and 65.09 µm, respectively. Children with high hyperopia had larger superior neuroretinal rim (NRR) width and larger vessel diameter than those with low and moderate hyperopia. In the univariate analysis, axial length was significantly associated with smaller superior NRR width (ß=-3.030, p<0.001), smaller temporal NRR width (ß=-1.469, p=0.020) and smaller vessel diameter (ß=-0.076, p<0.001). A mild inverse correlation was observed between the optic disc area and vertical disc diameter with age. CONCLUSION: AI-based CFP analysis showed that children with high hyperopia had larger mean vessel diameter but smaller vertical cup-to-disc ratio than those with low hyperopia. This suggests that AI can provide quantitative data on fundus parameters in children with hyperopia.

Reflectance spectroscopy: a non-invasive strategy to explore skin reactions to topical products.

Reflectance spectroscopy has emerged as a powerful analytical technique in the field of dermatology, offering a non-invasive strategy to assess several cutaneous properties and skin response to topical products. By analyzing reflected light across different wavelengths, reflectance spectroscopy allows the quantification of cutaneous parameters, such as erythema index and melanin content. Moreover, this analytical technique enables the monitoring of any changes in skin physiology facilitating the assessment of long-term effects of topical products as well as predicting cutaneous diseases. This review provides an overview of the application of reflectance spectroscopy in investigating skin properties and reaction to topical applied products, including both pharmaceutical and cosmetic formulations, thereby aiding in the development of personalized solutions tailored to individual needs.

Short-term effects of sunlight exposure on fundus blood flow perfusion in children: a randomised controlled trial.

AIM: To evaluate the short-term effects of different sunlight exposure on fundus blood flow perfusion (BFP) after near work. METHODS: In this parallel randomised controlled trial, 81 students aged 7-15 with spherical equivalent refraction between -2.00 and +3.00 diopters were randomly assigned to either a low-illuminance (4k lux) group (N=40) or high-illuminance (10k lux) (N=41). Following 1 hour indoor reading, participants had sunlight exposure matching their group's intensity for 15 minutes. BFPs in the superficial retina, deep retina and choroid were measured at four time points: pre-reading, post-reading, 5th-minute and 15th-minute sunlight exposure. RESULTS: Within the initial 5 minutes of sunlight exposure, the 10k lux group showed a tendency for decreased BFP, particularly in the choroid (superficial retina: -0.2, 95% CI -0.9 to 0.5; deep retina: -0.1, 95% CI -0.6 to 0.4; choroid: -0.4, 95% CI -0.8 to 0.0), while the 4k lux group exhibited an increase (superficial retina: 0.7, 95% CI 0.1 to 1.3; deep retina: 0.3, 95% CI -0.2 to 0.8; choroid: 0.1, 95% CI -0.2 to 0.5). From 5 to 15 minutes, BFP decreased in both groups. At the 5th-minute mark, the 10k lux group exhibited a greater decrease in choroid (10k -0.4 vs 4k 0.1, p=0.051). No significant difference was observed after 15 minutes of exposure. CONCLUSION: Higher illuminance sunlight exposure can restore fundus BFP more rapidly than lower; however, duration remains pivotal. To prevent myopia, continuous sunlight exposure for over 15 minutes is recommended to aid in reinstating the fundus BFP increased by near work. TRIAL REGISTRATION NUMBER: NCT05594732.

Refractive Outcomes Following Combined Cataract and Micro-Invasive Glaucoma Surgery.

PURPOSE: To compare refractive outcomes in eyes undergoing cataract extraction (CE) alone, CE with goniotomy (CE/goniotomy), and CE with Schlemm's canal stent (CE/SCS) insertion. DESIGN: Retrospective cohort study. PARTICIPANTS: Eyes from the Bascom Palmer Glaucoma Repository undergoing CE/goniotomy, CE/SCS insertion, or uncomplicated CE alone between July 2014 and February 2022 were identified. METHODS: Refraction data were analyzed at post-operative month (POM) 1 and 6 with Kruskal-Wallis and Dunn's tests. Anisometropia was defined as a spherical equivalent (SE) difference of ≥2D. MAIN OUTCOME MEASURES: The primary outcome was mean refraction at POM1 and POM6 across the three surgical groups. Secondary outcomes were comparisons of refraction and visual acuity among different goniotomy and SCS devices, as well as incidence of anisometropia. RESULTS: A total of 8,360 eyes (150 CE/goniotomy, 395 CE/SCS, and 7,815 CE alone) from 6,059 patients were analyzed. At POM1, mean SE in the CE/goniotomy, CE/SCS, and CE alone groups was -0.36±0.91D, -0.31±0.85D, and -0.39±0.88D respectively (p=0.019). Mean logMAR VA was 0.10±0.20, 0.08±0.19, and 0.14±0.26 respectively (p=0.002, CE/SCS vs. CE alone). No statistically significant differences were noted at POM6. Anisometropia occurred at POM1 in 2 patients (13.3%) in the CE/goniotomy-CE group, 1 patient (3.2%) in the CE/SCS-CE group, and 184 patients (4.9%) in the CE-CE group (p=0.217). At POM6, mean SEs were -0.38±0.97D (CE/goniotomy), -0.35±0.81D (CE/SCS), and -0.40±0.91D (CE alone; p=0.473). No significant differences in overall refractive outcomes were observed with different SCS or goniotomy devices. Among primary open-angle glaucoma (POAG) / normal-tension glaucoma (NTG) eyes, mean SE at POM1 was -0.36±0.73D (CE/goniotomy), -0.24±0.84D (CE/SCS), and -0.45±0.81D (CE alone; p<0.001). CONCLUSIONS: Concurrent SCS insertion or goniotomy with CE was associated with some statistically significant differences in postoperative refraction and visual acuity, although these small magnitude differences were unlikely to be clinically meaningful.

Vision screening and refraction of Greenlandic schoolchildren.

PURPOSE: To estimate the prevalence of amblyopia and refractive errors among 6-year-old children in Greenland and to assess the impact of incorporating autorefraction, stereoacuity and near visual acuity testing into vision screening. METHODS: In this cross-sectional study, 517 children (238 girls and 279 boys) from 21 locations in Greenland were screened using HOTV charts for distance and near visual acuity (VA), stereoacuity test and non-cycloplegic autorefraction. Referral criteria for further ophthalmological examination included a VA of ≥0.2 logMAR on the worse-seeing eye or an interocular VA difference of ≥2 lines. RESULTS: Initial screening identified amblyopia (defined as VA of ≥0.3 logMAR) in 7% (unilateral) and 3% (bilateral) of children. However, subsequent ophthalmological examinations confirmed amblyopia in under 40% of referrals. Significant interocular VA differences were found in 9%. The prevalence of refractive errors at the screening was 3% for myopia (≤-0.5 dioptres), 10% for hyperopia (>+2.0 dioptres) and 14% for astigmatism (≤-1.00 dioptres), while the corresponding prevalences at the ophthalmological examination were 4% for myopia, 8% for hyperopia and 6% for astigmatism. Combining screening measurements increased the positive predictive values, thereby enhancing screening accuracy. Specifically, the incorporation of autorefraction or stereoacuity with distance VA demonstrated to be the most effective combination. Six percent of the children were prescribed glasses after the screening procedure. CONCLUSION: This study provides the first visual profile of Greenlandic schoolchildren. Incorporating autorefraction, stereoacuity and near visual acuity in vision screenings enhanced the efficacy of detection of vision anomalies. Although this may lead to more false positives, accurate screening is crucial in regions with limited ophthalmological resources.

Refractive and ocular biometric characteristics of non-myopic and pseudomyopic eyes in mild hyperopic Chinese children aged 3-12 years.

Purpose: To investigate the refractive and ocular biometric characteristics of children with mild hyperopia and distinguish between non-myopic and pseudomyopic eyes before cycloplegia. Methods: The eligible children underwent refractive error measurements using a NIDEK autorefractor before and after the administration of 0.5 % tropicamide. Ocular biometric parameters, including axial length (AL), anterior chamber depth (ACD), and lens thickness (LT), were measured using the IOLMaster 700 before cycloplegia. We performed comparative analyses between the non-myopic and pseudomyopic groups, categorized based on whether the spherical equivalent (SE) before cycloplegia exceeded -0.50 diopters (D). Univariable and multivariable regression analyses were performed to control for confounding factors. Results: The final analysis included 968 eyes. The participants with pseudomyopia were more likely to be boys (P = 0.029), younger (P = 0.004), less hyperopic (P < 0.001) after cycloplegia, and exhibit a higher delta SE (P < 0.001) compared to the non-myopic participants. Pseudomyopic eyes were associated with a shallower ACD (P = 0.004) and thicker LT (P < 0.001) than non-myopic eyes. After adjusting for sex, age, and SE, pseudomyopic eyes showed increased AL (P = 0.001) and LT (P < 0.001) and decreased ACD (P = 0.005) compared with non-myopic eyes before cycloplegia. Conclusions: Among the children with mild hyperopia, pseudomyopia was more common in younger boys with a lower cycloplegic SE and higher delta SE. A thicker LT, shallower ACD, and increased AL may indicate the presence of pseudomyopia, which may provide insights into the rapid progression of myopia in children with pseudomyopia.

Shaping school for childhood myopia: the association between floor area ratio of school environment and myopia in China.

AIM: To investigate the association of floor area ratio (FAR), an indicator of built environments, and myopia onset. METHODS: This prospective cohort study recruited 136 753 children aged 6-10 years from 108 schools in Shenzhen, China at baseline (2016-2017). Refractive power was measured with non-cycloplegic autorefraction over a 2-year follow-up period. FAR was objectively evaluated using geographical information system technology. Mixed-effects logistic regression models were constructed to examine the association of FAR with a 2-year cumulative incidence of myopia among individuals without baseline myopia; multiple linear regression model, with a 2-year cumulative incidence rate of myopia at each school. RESULTS: Of 101 624 non-myopic children (56.3% boys; mean (SE) age, 7.657±1.182 years) included in the study, 26 391 (26.0%) of them developed myopia after 2 years. In the individual-level analysis adjusting for demographic, socioeconomic and greenness factors, an IQR in FAR was associated with a decreased risk of 2-year myopia incidence (OR 0.898, 95% CI 0.866 to 0.932, p<0.001). Similar findings were observed in the analysis additionally adjusted for genetic and behavioural factors (OR 0.821, 95% CI 0.766 to 0.880, p<0.001). In the school-level, an IQR increase in FAR was found to be associated with a 2.0% reduction in the 2-year incidence rate of myopia (95% CI 1.3% to 2.6%, p<0.001). CONCLUSIONS: Exposure to higher FAR was associated with a decreased myopia incidence, providing insights into myopia prevention through school built environments in China.

Evaluating a web-based visual acuity and refractive error self-assessment tool in myopic children.

INTRODUCTION: Demands for myopia management are rising. A web-based tool that allows home-performed self-assessments of visual acuity (VA) and refractive error may enable hybrid care pathways and aid in identifying those with deteriorating visual performance. The tool has been validated in adult populations, but has yet to be evaluated in children. This study compared home-performed VA and refraction self-assessments to conventional measurements obtained at the clinic in a population of myopic children. METHODS: Myopic children aged ≥6 years old were invited to perform web-based eye tests at home, assisted by a parent. At two myopia control clinics, they also underwent measurements of VA using a Snellen chart and refractive error using cycloplegic autorefraction. Agreement between the tests, repeatability of the web-based test and associations between clinical characteristics and web-based test accuracy were evaluated. RESULTS: A total of 147 children were enrolled, of whom 116 (51% male; mean age 13 ± 3 years; mean spherical equivalent refraction (SEQ) -5.58 ± 3.05) performed the web-based tests at home. Overall, the home-performed VA self-assessment and the Snellen chart assessment at the clinic agreed well (mean difference 0.03 ± 0.11 logMAR). A significant proportional bias was identified (ß 0.65, p < 0.001), indicating underestimated web-based VA scores when the child's vision declined. The sensitivity to detect VA poorer than 0.10 logMAR was 94%; the specificity was 71%. The web-based refractive error algorithm measured more myopia progression compared to clinic observations (mean difference SEQ 0.40 ± 0.51 dioptres). Age, sex or use of atropine drops were not significantly associated with test accuracy. CONCLUSIONS: The web-based test for self-assessing vision, performed at home by children with assistance from their parents, yielded VA scores with a precision similar to Snellen chart testing conducted in a clinical setting. However, the web-based refractive error algorithm overestimated myopia progression and requires recalibration for this specific age group.

Effect of Implanted Capsular Tension Ring on Postoperative Refractive Shift: A Systematic Review and Meta-Analysis.

BACKGROUND: The capsular tension ring is a novel assistant tool for cataract surgery; however, controversy exists in its co-implantation. The potential for hyperopic or myopic shift resulting from the co-implantation of the capsular tension ring and intraocular lens remains unclear. This study aimed to determine the postoperative refractive prediction error and the direction of refractive shift in cataract patients who underwent capsular tension ring co-implantation. METHODS: We conducted a systematic review and meta-analysis,searching electronic databases for studies of individuals diagnosed with cataracts receiving surgery with or without capsular tension ring implantation. Systematic searches were performed based on five databases: PubMed, Cochrane Library, Web of Science, Medline, and China National Knowledge Infrastructure. The primary outcome was the mean arithmetic refractive prediction error. Secondary outcomes were mean absolute refractive prediction error and the number of eyes within a certain refractive prediction error range. We applied a fixed-effectsmodel to pool effect sizes across trials using weighted mean differences (WMD) and risk ratios (RR) with their 95% confidence intervals (95% CI). Statistical heterogeneity scores were assessed with the I2statistic. RESULTS: A total of 407 affected eyes were included in eight independent clinical studies. Meta-analysis suggested significant differences both in short-term (≤1 month) co-implantation (WMD = 0.16, p < .001, 95% CI: -0.13 ~ 0.19) and long-term (≥3 months) co-implantation between the capsular tension ring co-implantation group and the control group (WMD = 0.19, p < .001, 95% CI: 0.15 ~ 0.23). However, no significant difference was observed in the high myopia subgroup whether capsular tension ring co-implantation (WMD = 0.03, p = .083, 95% CI: -0.27 ~ 0.34). Heterogeneity was not found among the studies. CONCLUSION: Compared to simple intraocular lens implantation, capsular tension ring co-implantation is more susceptible to developing hyperopic shifts in non-myopic cataract patients, probably related to anterior chamber depth. It requires careful consideration by clinicians when determining the target diopter preoperatively. However, interpretation is limited, because there is a lack of studies available for analysis. There still needs to be additional studies to expand the evidence base.

Anisomyopia and orthokeratology for myopia control - Axial elongation and relative peripheral refraction.

PURPOSE: To investigate axial elongation (AE) and changes in relative peripheral refraction (RPR) in anisomyopic children undergoing orthokeratology (ortho-k). METHODS: Bilateral anisomyopic children, 7-12 years of age, were treated with ortho-k. Axial length (AL) and RPR, from 30° nasal (N30°) to 30° temporal (T30°), were measured at baseline and every 6 months over the study period. AE, changes in RPR and changes in the interocular AL difference were determined over time. RESULTS: Twenty-six of the 33 subjects completed the 2-year study. The AE of the higher myopic (HM) eyes (at least 1.50 D more myopia than the other eye) (0.26 ± 0.29 mm) was significantly smaller than for the less myopic (LM) eyes (0.50 ± 0.27 mm; p = 0.003), leading to a reduction in the interocular difference in AL (p = 0.001). Baseline RPR measurements in the HM eyes were relatively more hyperopic at T30°, N20° and N30° (p ≤ 0.02) and greater myopic shifts were observed at T20° (p < 0.001), T30° (p < 0.001), N20° (p = 0.02) and N30° (p = 0.01) after lens wear. After 2 years of ortho-k lens wear, temporal-nasal asymmetry increased significantly, being more myopic at the temporal locations in both eyes (p < 0.001), while AE was associated with the change in RPR at N20° (ß = 0.134, p = 0.01). The interocular difference in AE was also positively associated with the interocular difference in RPR change at N30° (ß = 0.111, p = 0.02). CONCLUSIONS: Ortho-k slowed AE in bilateral anisomyopia, with slower growth in the HM eyes leading to a reduction in interocular AL differences. After ortho-k, RPR changed from hyperopia to myopia, with greater changes induced in the HM eyes, and slower AE was associated with a more myopic shift in RPR, especially in the nasal field of both eyes.

Saving one's face while saving one's soul? The refraction of tactical approaches to penance as a disciplinary device in Counter-Reformation Italy.

Sociohistorical research suggests that religious discourses and practices have been powerful in producing disciplined lines of conduct. Typically, however, this work has only considered the long-term consequences of discursive shifts or the one-sided outcomes of disciplinary practices. In contrast, this paper shows how the creative appropriation of disciplinary devices can instigate their transfiguration into additional disciplinary tools. By examining manuals for confession published in Counter-Reformation Italy, I identify three tactics via which believers allegedly approached Sacramental Penance as an impression management tool. The authors of these cultural objects detected the diffusion of these tactics and circulated their depictions to alert confessors and stigmatize believers who enacted them. These findings suggest that the theorizing of disciplining processes has to consider how the tactical appropriation of disciplinary practices can trigger processes of refraction via which their negative representations are reified and circulated as further disciplinary tools.

The CroMyop study: myopia progression in Croatian children and adolescents-a 15-year retrospective analysis.

Purpose: Myopia is a major global health issue, especially among children and adolescents. Understanding its traits and progression is vital for proper management and prevention. This study aimed to fill a gap in research by analyzing demographic and refractive data concerning myopia among children and adolescents in Croatia, with the goal of providing insights into myopia prevalence, progression rates, and associated risk factors within the Croatian population. Design: This retrospective study utilized a comprehensive dataset from pediatric ophthalmology clinics at the University Eye Department, University Hospital "Sveti Duh," Zagreb, Croatia. The dataset included electronic medical records spanning from January 2008 to July 2023, encompassing demographic and refractive data. Methods: Data analysis focused on individuals aged 4 to 18 years who were diagnosed with primary myopia and/or compound myopic astigmatism. Ophthalmic examinations, including visual acuity tests, cycloplegic refraction, and assessments for eye comorbidities, were conducted by experienced pediatric ophthalmologists. Statistical analysis, including t-tests, survival analysis, and logistic regression, was performed to assess myopia prevalence, progression rates, and associated factors. These analyses were adjusted for covariates such as age, parental myopia, and gender. Results: The study included 895 individuals, 51 premyopes, 813 low myopes, and 31 high myopes. The average age of diagnosis was 11.37 ± 3.59 years for premyopes, 11.18 ± 3.53 years for low myopes, and 11.44 ± 4.35 years for high myopes. The fastest progression occurred in 2021 and 2022, -0.5 ± 0.12 D/y for premyopes and - 0.45 ± 0.1 D/y for low myopes. Premyopic progression to low myopia was associated with age 7-9 years (HR 2.42, 1.53 to 3.21) and both parents being myopic (HR 920.27. 850.16 to 950.53). Low myopic individuals with both myopic parents displayed the fastest 11-24 months after first visit progression rates, -0.69 (-0.52 to -0.87) D/y, while the 7-9 age group demonstrated -0.36 (-0.24 to -0.45) D/y. Low myopes aged 7-9 years with baseline SE between -6 D and -4 D were more strongly associated with ≤ - 0.5 D progression (OR = 2.0, 95% CI -1.00 to 2.39). Conclusion: This study highlights the importance of environmental factors, genetics, and age in addressing myopia progression among Croatian youth, urging further research for effective local intervention strategies.