Bi-exponential description for different forms of refractive development.

It was recently established that the axial power, the refractive power required by the eye for a sharp retinal image in an eye of a certain axial length, and the total refractive power of the eye may both be described by a bi-exponential function as a function of age (Rozema, 2023). Inspired by this result, this work explores whether these bi-exponential functions are able to simulate the various known courses of refractive development described in the literature, such as instant emmetropization, persistent hypermetropia, developing hypermetropia, myopia, instant homeostasis, modulated development, or emmetropizing hypermetropes. Moreover, the equations can be adjusted to match the refractive development of school-age myopia and pseudophakia up to the age of 20 years. All of these courses closely resemble those reported in the previous literature while simultaneously providing estimates for the underlying changes in axial and whole eye power.

Accelerometer-Measured Daily Behaviors That Mediate the Association Between Refractive Status and Depressive Disorders.

Purpose: To identify the accelerometer-measured daily behaviors that mediate the association of refractive status with depressive disorders and enhance the understanding of behavioral differences in depression. Methods: Participants with baseline mean spherical equivalent (MSE) and 7-day accelerometer measurements from the UK Biobank were included in this cohort study. Refractive status was categorized as hyperopia and non-hyperopia. Four daily behaviors, including moderate to vigorous intensity physical activity (MVPA), light physical activity (LPA), sedentary, and sleep were recorded between 2013 and 2015. We also assessed 24-hour behavior patterns. Depression cases were defined through both questionnaires and hospital records over 10 years of follow-up. Results: Among 20,607 individuals, every 0.5-diopter increase in MSE was associated with a 6% higher risk of depressive disorders, with hyperopia participants at a higher risk than non-hyperopia participants (odds ratio, 1.14; 95% confidence interval, 1.05-1.23; P = 0.001). MVPA and sleep time significantly correlated with depressive disorders, with odds ratios of 0.79 and 1.14 (P < 0.05). MSE showed significant correlations with all four behaviors. The effects of MVPA and sleep duration on MSE and depressive disorders varied throughout the day. Mediation analyses showed that MVPA and sleep partially mediated the relationship between MSE and depressive disorders, with 35.2% of the association between moderate to high hyperopia and depression mediated by MVPA. Conclusions: Physical activity and sleep significantly mediate the relationship between MSE and depressive disorders. Translational Relevance: The mediation effect of MVPA highlights its therapeutic potential in reducing the risk of depression among individuals with moderate to severe hyperopia. Interventions aimed at increasing daytime MVPA and decreasing daytime sleep could enhance mental health in this vulnerable group.

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.

The effects of refractive status on the outcomes of strabismus surgery in patients with esotropia.

BACKGROUND: The success of the strabismus surgery can hinge on several factors. One of these factors is refractive condition like hyperopia or myopia. Our study seeks to evaluate the surgical outcomes in patients with esotropia and myopia. METHODS: This case-control study encompassed all surgical cases of esotropia at Torfe and Negah Hospital between 2016 and 2021, which satisfied our specified inclusion criteria. The initial variables from electronic medical records were collected, including demographic, clinical, and surgery-related factors. At the final follow-up appointment, the level of eye deviation, both at distance and near, was recorded. We considered the operation a "success" for patients with a post-surgery distance eye deviation of 10(Pd) or less. Patients with greater deviation were classified as surgery failure. Statistical analyses were executed using SPSS software (version 16.0), and a P-value less than 0.05 was considered significant. RESULTS: Of the 194 patients evaluated, 112 were incorporated into the study. Surgical failure was observed in 14.29% of myopic patients, 29.79% of hyperopic patients, and 31.82% of emmetropic patients. The myopia group displayed a 0.19 odd ratio for surgical failure compared to the combined hyperopia and emmetropia groups, not statistically significant (OR: 0.19, CI 95%: 0.03-1.02). Additionally, patients diagnosed with Lateral Rectus Under-action were found to be 6.85 times more likely to experience surgery failure(OR: 6.85, CI 95%: 1.52-30.94). An elevated risk of surgical failure was also identified in patients who underwent Inferior Oblique Weakening procedure, indicated by a 3.77-fold increase in the odds ratio for failure(OR: 3.77, CI 95%: 1.08-13.17). CONCLUSION: In our study, despite numerical disparities, there was no statistical difference among the success rates of all esotropia patients with different refractive errors. The patients with LRUA or IOOA showed lower success rates. Myopic patients had higher post-op overcorrection with lower reoperation rates compared to hyperopic or emmetropic patients.

Immediate Sequential Bilateral Implantable Collamer Lens Surgery Is Safe and Effective.

PURPOSE: To assess the clinical outcomes and safety profiles of patients who underwent immediate sequential bilateral phakic lens surgery. METHODS: This retrospective multicenter study included 254 consecutive patients (508 eyes) who underwent bilateral same-day Implantable Collamer Lens (ICL) (STAAR Surgical) surgery. The authors focused on 1-year postoperative clinical outcomes and adverse events. RESULTS: In the initial cohort, 176 patients (352 eyes) met inclusion criteria. Of these, 335 eyes underwent myopic ICL placement, and 17 eyes received a hyperopic ICL. Notably, 87% of eyes achieved ±0.50 diopters (D) and 95% achieved ±1.00 D of the intended refraction. One year postoperatively, 78% of eyes demonstrated optimal vaulting (250 to 750 µm), with a significant 19% reduction in vaulting observed over the 12 months (P < .001). Only minor adverse events, including early cataract formation (1 case), secondary toric ICL rotation (3 cases), and ICL exchange due to inappropriate vaulting (6 cases), were noted. CONCLUSIONS: The findings corroborate the safety and efficacy of immediate sequential bilateral phakic lens surgery and indicate its potential as a treatment option. The low incidence of minor adverse events further reinforces its favorable safety profile. [J Refract Surg. 2024;40(5):e313-e320.].

Ocular Biometric Components in Hyperopic Children and a Machine Learning-Based Model to Predict Axial Length.

Purpose: The purpose of this study was to investigate the development of optical biometric components in children with hyperopia, and apply a machine-learning model to predict axial length. Methods: Children with hyperopia (+1 diopters [D] to +10 D) in 3 age groups: 3 to 5 years (n = 74), 6 to 8 years (n = 102), and 9 to 11 years (n = 36) were included. Axial length, anterior chamber depth, lens thickness, central corneal thickness, and corneal power were measured; all participants had cycloplegic refraction within 6 months. Spherical equivalent (SEQ) was calculated. A mixed-effects model was used to compare sex and age groups and adjust for interocular correlation. A classification and regression tree (CART) analysis was used to predict axial length and compared with the linear regression. Results: Mean SEQ for all 3 age groups were similar but the 9 to 11 year old group had 0.49 D less hyperopia than the 3 to 5 year old group (P < 0.001). With the exception of corneal thickness, all other ocular components had a significant sex difference (P < 0.05). The 3 to 5 year group had significantly shorter axial length and anterior chamber depth and higher corneal power than older groups (P < 0.001). Using SEQ, age, and sex, axial length can be predicted with a CART model, resulting in lower mean absolute error of 0.60 than the linear regression model (0.76). Conclusions: Despite similar values of refractive errors, ocular biometric parameters changed with age in hyperopic children, whereby axial length growth is offset by reductions in corneal power. Translational Relevance: We provide references for optical components in children with hyperopia, and a machine-learning model for convenient axial length estimation based on SEQ, age, and sex.

Uneven Corneal Epithelial Redistribution After Femtosecond Laser-Assisted Lenticule Intrastromal Keratoplasty in Correcting Moderate-to-High Hyperopia.

PURPOSE: To evaluate the characteristic of corrective epithelial thickness after femtosecond laser-assisted lenticule intrastromal keratoplasty (LIKE) to correct moderate-to-high hyperopia. METHODS: The prospective case series study of the LIKE procedure was performed to correct moderate-to-high hyperopia. The epithelial thickness map was generated by anterior segment optical coherence tomography (AS-OCT) in the corneal central 9-mm zone. Keratometry and corneal higher order aberrations were analyzed by Pentacam (Oculus Optikgeräte GmbH) preoperatively and postoperatively. RESULTS: In the 26 eyes of 13 participants who underwent the LIKE procedure for moderate-to-high hyperopia, the attempted spherical equivalence (SEQ) was +6.50 ± 1.09 diopters (D). Compared to the preoperative epithelial thickness maps, the postoperative epithelial thickness had become significantly thinner in the central 5-mm zone; the difference was 6 to 7 µm. The paracentral epithelium performed nonuniform remodeling; the thinnest epithelial thickness was located in the inferotemporal section, which has the greatest difference from the superonasal; the difference between these two was approximately 3 µm. Through correlation analysis, it was found that the sections with thinner epithelium were significantly related to corneal curvature and corneal vertical coma. CONCLUSIONS: The LIKE procedure can be used to correct moderate-to-high hyperopia. This study further indicated the epithelial remodeling characteristic after the LIKE procedure: the central and paracentral corneal epithelial thickness becomes thinner, and the epithelial thickness distributes non-uniformly, which may be the important factor of the postoperative curvature asymmetric distribution and induction of corneal vertical coma. [J Refract Surg. 2024;40(5):e321-e327.].

[Quantitative comparison of binocular suppression of patients with anisometropic amblyopia and ametropic amblyopia].

Objective: To explore the differences in clinical characteristics and interocular interactions between patients with anisometropic amblyopia and ametropic amblyopia. Methods: Cross-sectional study. The newly diagnosed anisometropic (the binocular difference in spherical equivalent≥1.00 D) amblyopia patients and ametropic amblyopia patients (aged 4 to 6 years) in Beijing Tongren Hospital from January 2020 to December 2022 were involved. Patients were further categorized by the refractive status after cycloplegia, including hyperopia, myopia, astigmatism, hyperopia with astigmatism, myopia with astigmatism, mild anisometropia and severe anisometropia. Quantitative measurements of best-corrected visual acuity (logMAR), stereoacuity (transformed to log units), perceptual eye position and interocular suppression were performed, and the differences between groups were analyzed. The rank sum test was used for statistical evaluation. Results: The average age of 45 ametropic amblyopia patients (21 males and 24 females) and 84 anisometropic amblyopia patients (48 males and 36 females) was 5.0 (4.0, 5.0) years and 5.0 (4.0, 6.0) years, respectively. The interocular differences in spherical equivalent [2.56 (1.50, 4.19) D vs. 0.25 (0.13, 0.56) D] and best-corrected visual acuity [0.40 (0.18, 0.70) logMAR vs. 0.07 (0.00, 0.12) logMAR] were larger in patients with anisometropic amblyopia than those with ametropic amblyopia. The anisometropic amblyopia patients had worse stereoacuity [2.60 (2.00, 2.90) log arcsec vs. 2.00 (2.00, 2.30) log arcsec] and deeper suppression [20.0% (13.3%, 40.0%) vs. 10.0% (0, 23.3%)], compared with the ametropic amblyopia patients. The differences were all statistically significant (P<0.05). The suppression and stereoacuity between patients with hyperopic anisometropic amblyopia [suppression, 30.0% (17.5%, 50.0%); stereoacuity, 2.90 (2.30, 2.90) log arcsec] and astigmatic anisometropic amblyopia [suppression, 10.0% (0, 20.0%); stereoacuity, 2.00 (2.00, 2.30) log arcsec] were significantly different (P<0.05). The differences of suppression and stereoacuity between patients with severe (binocular difference in spherical equivalent>2.50 D) [suppression, 30.0% (20.0%, 53.3%); stereoacuity, 2.90 (2.57, 2.90) log arcsec] and mild anisometropia [suppression, 20.0% (0, 30.0%); stereoacuity, 2.00 (2.00, 2.90) log arcsec] were also statistically significant (P<0.05). Conclusions: Patients with anisometropic amblyopia have deeper binocular suppression, worse stereoacuity and more severe binocular interaction abnormality than those with ametropic amblyopia. The severity of anisometropia affects the degree of the interaction abnormality.

The Parameters Governing the Anti-Myopia Efficacy of Chromatically Simulated Myopic Defocus in Tree Shrews.

Purpose: We previously showed that exposing tree shrews (Tupaia belangeri, small diurnal mammals closely related to primates) to chromatically simulated myopic defocus (CSMD) counteracted small-cage myopia and instead induced hyperopia (approximately +4 diopters [D]). Here, we explored the parameters of this effect. Methods: Tree shrews were exposed to the following interventions for 11 days: (1) rearing in closed (n = 7) or open (n = 6) small cages; (2) exposed to a video display of Maltese cross images with CSMD combined with overhead lighting (n = 4); (3) exposed to a video display of Maltese cross images with zero blue contrast ("flat blue," n = 8); and (4) exposed to a video display of black and white grayscale tree images with different spatial filtering (blue pixels lowpass <1 and <2 cycles per degree [CPD]) for the CSMD. Results: (1) Tree shrews kept in closed cages, but not open cages, developed myopia. (2) Overhead illumination reduced the hyperopia induced by CSMD. (3) Zero-blue contrast produced hyperopia but slightly less than the CSMD. (4) Both of the CSMD tree images counteracted small cage myopia, but the one low pass filtering blue <1 CPD was more effective at inducing hyperopia. Conclusions: Any pattern with reduced blue contrast at and below approximately 1 CPD counteracts myopia/promotes hyperopia, but maximal effectiveness may require that the video display be the brightest object in the environment. Translational Relevance: Chromatically simulated myopic blur might be a powerful anti-myopia therapy in children, but the parameter selection could be critical. Issues for translation to humans are discussed.

Retinal Changes From Hyperopia to Myopia: Not All Diopters Are Created Equal.

Purpose: To quantitatively characterize retinal changes across different quantiles of refractive error in 34,414 normal eyes of 23,064 healthy adults in the UK Biobank. Methods: Twelve optic disc (OD), foveal and vascular parameters were derived from color fundus photographs, correcting for ocular magnification as appropriate. Quantile regression was used to test the independent associations between these parameters and spherical equivalent refraction (SER) across 34 refractive quantiles (high hyperopia to high myopia)-controlling for age, sex and corneal radius. Results: More negative SER was nonlinearly associated with greater Euclidian (largely horizontal) OD-fovea distance, larger OD, less circular OD, more obliquely orientated OD (superior pole tilted towards the fovea), brighter fovea, lower vascular complexity, less tortuous vessels, more concave (straightened out towards the fovea) papillomacular arterial/venous arcade and wider central retinal arterioles/venules. In myopia, these parameters varied more strongly with SER as myopia increased. For example, while every standard deviation (SD) decrease in vascular complexity was associated with 0.63 D (right eye: 95% confidence interval [CI], 0.58-0.68) to 0.68 D (left eye: 95% CI, 0.63-0.73) higher myopia in the quantile corresponding to -0.60 D, it was associated with 1.61 D (right eye: 95% CI, 1.40-1.82) to 1.70 D (left eye: 95% CI, 1.56-1.84) higher myopia in the most myopic quantile. OD-fovea angle (degree of vertical separation between OD and fovea) was found to vary linearly with SER, but the magnitude was of little practical importance (less than 0.10 D variation per SD change in angle in almost all refractive quantiles) compared with the changes in OD-fovea distance. Conclusions: Several interrelated retinal changes indicative of an increasing (nonconstant) rate of mechanical stretching are evident at the posterior pole as myopia increases. These changes also suggest that the posterior pole stretches predominantly in the temporal horizontal direction.

Effect of spectacle correction on hyperopic children.

Background: Hyperopia is a significant refractive error in children, often leading to vision impairment. This study aimed to investigate whether partial or full spectacle correction is benefit for hyperopia in preschool-aged children. Methods: A retrospective study was conducted on hyperopic children visited to teaching medical center outpatient clinic between October 2011 and October 2018, and were categorized into three groups: full correction, overcorrection, and undercorrection. The study was approved by the institutional ethical committee of Tri-Service General Hospital. Results: Following a minimum of one-year follow-up period, no statistically significant differences were observed in best-corrected visual acuity (BCVA) among children receiving full, over, or under spectacle correction. Notably, the overcorrection group exhibited a significant reduction in spherical equivalent (SE) compared to both the full and under correction groups, indicating a better SE with spectacle overcorrection. Conclusions: Spectacle overcorrection may offer potential benefits for enhancing SE in preschool children with hyperopia. Nevertheless, further investigation through randomized controlled trials is warranted to establish the validity of this approach and its impact on visual outcomes in this hyperopic pediatric population.

Longitudinal Changes in Refractive Development in Highly Hyperopic Children: A 2.6-11.2 Year Follow-up of Preschoolers Diagnosed with High Hyperopia.

PURPOSE: This study aims to elucidate the longitudinal refractive and ocular biometric alterations in preschool children with high hyperopia who underwent early interventions. METHODS: We conducted a retrospective analysis of preschool children diagnosed with high hyperopia at Tianjin Medical University Eye Hospital between 2011 and 2023. Inclusion criteria required an initial examination with cycloplegic refraction, bilateral spherical equivalent power (SE) ≥ +5.00D with a difference <1.00D, a minimum two-year follow-up, and at least three ocular biometric measurements. The annual axial growth rate evaluated emmetropization in highly hyperopic children. We applied Restricted Cubic Spline (RCS) models to explore potential nonlinear relationships between age and spherical equivalent, axial length, corneal curvature, and axial length-to-corneal curvature ratio. Additionally, Mixed-effects models were employed to investigate factors associated with changes in refractive error and axial length. RESULTS: The study enrolled 60 eligible subjects, with a median initial diagnosis age of 3.5 years (IQR, 2.8-4.9 years) and a median last visit age of 9.3 years (IQR, 8.1-10.8 years). The average follow-up duration was 5.7 years. RCS analysis revealed notable nonlinear changes in spherical equivalent power, axial length, and axial length-to-corneal curvature ratio, although corneal curvature displayed no statistically significant nonlinear trend. Factors affecting SE changes included the presence of strabismus, the use of cycloplegia, baseline SE, and age. Conversely, changes in axial length solely correlated with baseline axial length and age. CONCLUSION: Highly hyperopic preschool children undergoing early intervention display a marked emmetropization tendency, though most still remain moderately to highly hyperopic, with the progression of refractive changes showing non-uniform patterns with respect to age.

Tessellated fundus occurs earlier than myopia in children aged 3-6 years.

BACKGROUND/OBJECTIVES: Tessellated fundus can exist in normal healthy eyes. This study aims to evaluate the occurrence and influencing factors of tessellated fundus in preschool children aged 3-6 years. SUBJECTS/METHODS: This kindergarten-based cross-sectional study included 1716 children with an age range of 3-6 years. All participants underwent a comprehensive eye examination and a questionnaire. According to the number of quadrants occupied by tessellated fundus around the optic disc in fundus photographs, it was divided into four grades. RESULTS: 600 (35.0%) children had peripapillary tessellation. According to the spherical equivalent (SE), the subjects were divided into three groups: Hyperopia group (SE > + 0.75D, n = 1194)；Pre-myopia group (-0.50D < SE ≤ + 0.75D, n = 455); Myopia group (SE ≤ -0.50D, n = 67). The proportion of peripapillary tessellated fundus was 33.0%, 38.0%, 50.7% respectively. According to the regression analysis, in the non-myopia group (Pre-myopia group and Hyperopia group), the occurrence of peripapillary tessellated fundus was associated with longer axial length (OR, 1.566; 95% CI: 1.229-1.996, p < 0.001) and larger corneal radius of curvature (OR, 1.837; 95% CI: 1.006-3.354, p = 0.048). However, in Pre-myopia group, the corneal radius of curvature was not associated with the occurrence of peripapillary tessellated fundus (p = 0.830). In Hyperopia group, the corneal radius of curvature was associated with the occurrence of peripapillary tessellated fundus (OR, 2.438; 95% CI: 1.160-5.122, p = 0.019). CONCLUSIONS: The occurrence of peripapillary tessellated fundus is more than 30% in 3-6 year old preschool children. Tessellated fundus can also occur in non-myopic children, and is related to the length of axial length and large radius of corneal curvature.

Laser vision correction after radial keratotomy: systematic review and meta-analysis.

Laser vision correction for residual refractive errors in patients with previous radial keratotomy (RK) presents a challenging task. Different techniques have been used with varying outcomes. This study aimed to systematically review published articles on refractive surgeries in post-RK patients by conducting a search on PubMed, Scopus, and Web of Science. The final analysis included 35 studies that described a total of 888 eyes. Our systematic review and meta-analysis demonstrated a significant improvement in uncorrected distance visual acuity (UDVA) for photorefractive keratectomy (PRK), topography-guided PRK, wavefront-guided PRK, and femtosecond laser-assisted in situ keratomileusis (LASIK) while mechanical microkeratome LASIK did not yield such significant improvements. Moreover, our results suggest that post-RK patients with hyperopia had a significant improvement in UDVA, whereas no such improvement was observed in patients with myopia.

Hyperopic LASIK and postoperative corneal steepness: revisiting the 49-diopter limit.

PURPOSE: To compare corrected distance visual acuity (CDVA) outcomes of hyperopic laser in situ keratomileusis (LASIK) with a postoperative corneal steepness above vs below 49 diopters (D). SETTING: Care-Vision Laser Centers, Tel-Aviv, Israel. DESIGN: Retrospective study. METHODS: This study included consecutive patients who underwent hyperopic LASIK between January 2013 and December 2019. Hyperopic patients were divided into 2 groups based on postoperative corneal steepness with steep corneas defined >49.0 D and the control group ≤49.0 D. Adjustments were performed to account for differences in baseline and intraoperative parameters. RESULTS: Overall, 1703 eyes of 1703 patients were included. Mean age was 48.3 ± 10.0 years, and 45.3% were male. Preoperatively, the steep group (2.4%, n = 41/1703) had steeper mean (44.6 D vs 43.1 D, P < .001) and steep (45.1 D vs 43.5 D, P < .001) keratometry, worse logMAR CDVA (0.07 vs 0.04, P = .02), and higher sphere (4.9 D vs 2.9 D, P < .001). Intraoperatively, they had a higher spherical treatment (4.6 D vs 2.8 D, P < .001). After hyperopic LASIK, the steep group had worse logMAR CDVA (0.10 vs 0.06, P = .01). However, after accounting for differences in baseline and spherical treatment, no significant differences were found in postoperative logMAR CDVA (0.06 vs 0.06, P = .99). The factors that remained associated with worse postoperative CDVA were higher spherical treatment (0.01 logMAR per 1 D, P < .001) and preoperative CDVA (0.60 logMAR per 1.00 logMAR, P < .001). CONCLUSIONS: Postoperative corneal steepness greater than 49 D is not associated with worse visual outcomes after hyperopic LASIK. However, lower preoperative visual potential and higher spherical treatment applied are associated with worse outcomes. The 49 D cutoff should be revisited.

Effect of residual sphere on uncorrected visual acuity and satisfaction in patients with monofocal and multifocal intraocular lenses.

PURPOSE: To assess the effect of residual sphere on vision and satisfaction in pseudophakic patients. SETTING: Private clinics, United Kingdom. DESIGN: Retrospective case series. METHODS: A multivariate model evaluated the effect of 1-month residual sphere on outcomes of pseudophakic patients. Odds ratios (ORs) were calculated to assess the relative risk of not achieving ≥20/20 monocular uncorrected distance visual acuity (UDVA), ≥20/50 uncorrected near visual acuity (UNVA), and not being satisfied with vision. ORs were assessed for residual sphere -1.00 to +1.00 diopter (D) in quarter-diopter steps, using 0.00 D as a reference. RESULTS: The analysis included 38 828 multifocal and 11 571 monofocal intraocular lenses (IOLs). The residual myopic sphere ≤-0.25 D and hyperopic sphere ≥+0.50 D had a clinically meaningful effect on UDVA. Although monofocal IOLs had an improvement in UNVA with every additional 0.25 D of myopia, the change in ORs with increasing myopia was not significant for multifocal IOLs. The mean improvement in UNVA comparing eyes with 0.00 D and -1.00 D sphere was 0.26 logMAR for monofocal and 0.03 logMAR for multifocal IOLs. Low near-addition IOLs had a slightly higher gain in UNVA with increasing myopia, but the gain was not as substantial as with monofocal IOLs. The effect of ametropia on satisfaction was more pronounced for multifocal IOLs. For every 0.25 D of residual myopia, there was >25% increase in dissatisfied patients. CONCLUSIONS: Although myopia improved UNVA in eyes with monofocal IOL, multifocal IOLs did not benefit from residual myopia. Multifocal IOL patients desiring distance vision should be targeted closest to emmetropia, even if it means targeting slight hyperopia.

Contrast Sensitivity and Stereoacuity in Successfully Treated Refractive Amblyopia.

Purpose: To assess whether monocular contrast sensitivity and stereoacuity impairments remain when visual acuity is fully recovered in children with refractive amblyopia. Methods: A retrospective review of 487 patients diagnosed with refractive amblyopia whose visual acuity improved to 0.08 logMAR or better in both eyes following optical treatment was conducted. Measurements of monocular contrast sensitivity and stereoacuity had been made when visual acuity normalized. All patients had been treated with refractive correction for approximately 2 years following diagnosis. No other treatments were provided. Monocular contrast sensitivity was measured using the CSV-1000E chart for children 6 years of age or younger and a psychophysical technique called the quick contrast sensitivity function in older children. Stereoacuity was measured using the Random Dot Test that includes monocular cues and the Randot Stereoacuity Test that does not have monocular cues. Results: Statistically significant interocular differences in contrast sensitivity were observed. These differences tended to occur at higher spatial frequencies (12 and 18 cycles per degree). Stereoacuity within the age-specific normal range was achieved by 47.4% of patients for the Random Dot Test and only 23.1% of patients for the Randot Stereoacuity Test. Conclusions: Full recovery of visual acuity following treatment for refractive amblyopia does not equalize interocular contrast sensitivity or restore normal stereopsis. Alternative therapeutic approaches that target contrast sensitivity and/or binocular vision are required.

Ablation of mpeg+ Macrophages Exacerbates mfrp-Related Hyperopia.

Purpose: Proper refractive development of the eye, termed emmetropization, is critical for focused vision and is impacted by both genetic determinants and several visual environment factors. Improper emmetropization caused by genetic variants can lead to congenital hyperopia, which is characterized by small eyes and relatively short ocular axial length. To date, variants in only four genes have been firmly associated with human hyperopia, one of which is MFRP. Zebrafish mfrp mutants also have hyperopia and, similar to reports in mice, exhibit increased macrophage recruitment to the retina. The goal of this research was to examine the effects of macrophage ablation on emmetropization and mfrp-related hyperopia. Methods: We utilized a chemically inducible, cell-specific ablation system to deplete macrophages in both wild-type and mfrp mutant zebrafish. Spectral-domain optical coherence tomography was then used to measure components of the eye and determine relative refractive state. Histology, immunohistochemistry, and transmission electron microscopy were used to further study the eyes. Results: Although macrophage ablation does not cause significant changes to the relative refractive state of wild-type zebrafish, macrophage ablation in mfrp mutants significantly exacerbates their hyperopic phenotype, resulting in a relative refractive error 1.3 times higher than that of non-ablated mfrp siblings. Conclusions: Genetic inactivation of mfrp leads to hyperopia, as well as abnormal accumulation of macrophages in the retina. Ablation of the mpeg1-positive macrophage population exacerbates the hyperopia, suggesting that macrophages may be recruited in an effort help preserve emmetropization and ameliorate hyperopia.

Short-Term Exposure to Blue Light Shows an Inhibitory Effect on Axial Elongation in Human Eyes Independent of Defocus.

Purpose: Given the potential role of light and its wavelength on ocular growth, we investigated the effect of short-term exposure to the red, green, and blue light on ocular biometry in the presence and absence of lens-induced defocus in humans. Methods: Twenty-five young adults were exposed to blue (460 nm), green (521 nm), red (623 nm), and white light conditions for 1-hour each on 4 separate experimental sessions conducted on 4 different days. In each light condition, hyperopic defocus (3D) was induced to the right eye with the fellow eye experiencing no defocus. Axial length and choroidal thickness were measured before and immediately after the light exposure with a non-contact biometer. Results: Axial length increased from baseline after red light (mean difference ± standard error in the defocussed eye and non-defocussed eye = 11.2 ± 2 µm and 6.4 ± 2.3 µm, P < 0.001 and P < 0.01, respectively) and green light exposure (9.2 ± 3 µm and 7.0 ± 2.5 µm, P < 0.001 and P < 0.001) with a significant decrease in choroidal thickness (P < 0.05, both red and green light) after 1-hour of exposure. Blue light exposure resulted in a reduction in axial length in both the eyes (-8.0 ± 3 µm, P < 0.001 in the defocussed eye and -6.0 ± 3 µm, P = 0.11 in the non-defocused eye) with no significant changes in the choroidal thickness. Conclusions: Exposure to red and green light resulted in axial elongation, and blue light resulted in inhibition of axial elongation in human eyes. Impact of such specific wavelength exposure on children and its application in myopia control need to be explored.