To examine the developmental patterns of refractive error and optical components in hyperopic children with infantile (onset ≤12 months of age) accommodative or late-onset (18–48 months of age) accommodative esotropia. This prospective longitudinal study included children with infantile (n = 34) or late-onset (n = 63) accommodative esotropia. Axial length (AL), anterior chamber depth (ACD), lens thickness (LT) and keratometry (K1, K2) were obtained with a Lenstar LS 900. Lenstar measures were recorded <6 months after cycloplegic spherical equivalent refraction (SER) was derived. An initial examination was conducted at 5.8 ± 1.5 years of age, with a follow-up duration of 4.8 ± 0.8 years. A linear mixed-effects model was used to estimate the rate of individual development for each ocular component and SER, and to compare the two groups. All biometric components changed with age. The rates of change with age for SER and AL were significantly different between the infantile and late-onset groups (SER: −0.18 vs. −0.12D/year, p < 0.001; AL: 0.16 vs. 0.14 mm/year, p < 0.01). The rate of change with age of the AL/CR ratio was significantly different between the infantile and late-onset groups (0.019 vs. 0.016, p < 0.001). No significant differences in the rates of change in ACD, LT, K1 or K2 were identified. Major ocular biometric components in children continue to mature in both infantile and late-onset accommodative esotropia. Annual change in axial length is smaller in late-onset accommodative esotropia than for infantile accommodative esotropia, consistent with less change in the SER with age.

To compare the longitudinal development of spherical equivalent refraction (SER) and ocular biometric components in the more hyperopic (MoreH) and less hyperopic (LessH) eyes of children with hyperopic anisometropia. This prospective longitudinal study included 36 children aged 4 to <13 years with hyperopic anisometropia without strabismus. Based on a best-corrected interocular visual acuity difference ≥0.20 logMAR, participants were classified as amblyopic (N = 31) or non-amblyopic (N = 5). SER was derived from cycloplegic refraction and anisometropia was defined as an interocular SER difference ≥1 D. Axial length (AL), anterior chamber depth (ACD), lens thickness (LT), and keratometry (K1, K2) were obtained. Corneal curvature (CR) was calculated and the AL/CR ratio determined. Mean follow-up was 3.7 ± 1.4 years, with 5.8 ± 2.4 visits per child. A linear mixed-effects model estimated the rate of change for SER and the ocular components, comparing the MoreH and LessH eyes. Baseline anisometropia was 2.66 ± 1.22 D. There were significant differences between the MoreH and LessH eyes for baseline AL, ACD and AL/CR (all p < 0.05). SER change with age was slower for the MoreH than the LessH eyes (−0.11 vs. −0.31 D/year, p < 0.001). The rates of change for AL (0.11 vs. 0.19 mm/year, p < 0.05) and AL/CR (0.01 vs. 0.02, p < 0.001) also were slower for the MoreH eyes. Anisometropia increased with age in the amblyopic subgroup (0.08 D/year) and decreased in the non-amblyopic subgroup (−0.17/D/year; p < 0.001). In children with hyperopic anisometropia, axial elongation was slower in the MoreH than in the LessH eyes, particularly in those with amblyopia.

P URPOSE . When treating amblyopia, it is important to define when visual acuity (VA) is no longer improving (i.e., stable) because treatment decisions may be altered based on this determination. M ETHODS . Simulated observed VAs, incorporating measurement error, were compared with simulated true VAs to determine false-positive and false-negative rates for stable VA for six rules (using single VA or test/retest measurements, with or without averaging, over two or three visits). Four HOTV VA profiles were modeled: stable or improving VA over time with each of patching and spectacles. R ESULTS . Across six rules and two treatments, when true VA was stable, false-negative rates for stability ranged from 26% to 67%; when true VA was improving, false-positive rates for stability ranged from 0% to 38%. Single VA measurements at consecutive visits had a false-negative rate of 30% with patching and 29% with spectacles, a false-positive rate of 38% with patching and 35% with spectacles. Averaging two VA tests at each visit slightly increased the false-negative rate (35% with patching and 36% with spectacles), while reducing the false-positive rate (22% with patching and 21% with spectacles). C ONCLUSIONS . Comparing false-negative and false-positive rates for stability across rules allows selection of the most appropriate rule for clinical practice or research. When considering less desirable treatments, a rule with a lower false-negative rate is preferable, whereas a rule with a lower false-positive rate would be preferred when it is important to correctly classify improving VA.

Monocular deprivation (MD) amblyopia caused by a dense unilateral congenital or infantile cataract leads to both sensory and ocular motor deficits, which can in turn affect motor performance. Previous research shows reduced fine motor skills in children with MD amblyopia on standardized tasks. Here, we evaluate eye-hand coordination during visually-guided reaching in MD amblyopia. A group of 17 children aged 7-15 years with MD amblyopia resulting from a unilateral cataract and a group of 41 age-similar control children were enrolled. During binocular viewing, children's reaching movements (LEAP Motion Controller) and eye movements (EyeLink 1000 binocular eye tracker) were recorded as they reached to touch a dot displayed at one of four locations (±5 deg or ±10 deg) on a computer monitor. Saccade and reach kinematic measures were assessed between groups, and factors associated with impairments in the MD amblyopia group were evaluated. The MD amblyopia group as a whole had impaired saccade (lower saccade gain, reduced saccade precision, more reach-related saccades) and reach (longer total reach duration, slower peak velocity, reduced touch accuracy) kinematics compared to controls. However, performance was worse in those with a poorer visual acuity outcome (≥0.7 logMAR) compared to good visual acuity outcome (≤0.6 logMAR). MD amblyopia impacts the development of eye-hand coordination during reaching, particularly in those with a poorer visual acuity outcome. Longer deceleration in the final approach and more reach-related saccades may suggest an inability to adapt or form an efficient compensatory strategy and may also be indicative of impaired on-line control.

Ophthalmic professional organizations such as the American Association for Pediatric Ophthalmology and Strabismus (AAPOS) strive to support the optimal detection, prevention, and treatment of amblyopia to reduce the community burden of vision loss. To support population-level monitoring with regard to outcomes of childhood amblyopia screening and treatment, the AAPOS Vision Screening and the Research committees propose a set of guidelines for assessing population prevalence of persistent vision impairment due to amblyopia. The committees defined "residual amblyopia" as persistent vision impairment with best-corrected visual acuity worse than logMAR 0.3 (20/40) in one eye with an interocular difference, or visual acuity worse than logMAR 0.3 in both eyes, attributable to unilateral or bilateral amblyopia respectively, with visual acuity deficits not due to other organic causes. Epidemiological assessment of residual amblyopia should be made at an age when amblyopia should have already been detected and treated (8 years). A standardized assessment of residual amblyopia has the potential to promote public health interventions, including quality-improvement projects, for amblyopia screening and subsequent treatment.

Background One rationale for dichoptic amblyopia therapy is that it may promote recovery of binocular function. Yet data on binocular outcomes in anisometropic amblyopia following dichoptic therapy are sparse. We report factors associated with pre- and post-treatment binocular function in anisometropic amblyopia, and examine binocular function in children who recover normal visual acuity compared to those with residual amblyopia. Methods Baseline and outcome stereoacuity and binocular function (BF) scores were pooled across 185 children (3-12 years of age) with anisometropic amblyopia who participated in one of eight clinical trials of contrast-rebalanced dichoptic amblyopia treatment conducted at a single site. Associations of baseline variables (visual acuity, suppression, type and amount of anisometropia, prior treatment) with baseline and outcome stereoacuity and BF scores were analyzed, as well the association between improvement in visual acuity with improvement in stereoacuity and BF scores. Results Better baseline stereoacuity and BF score were associated with better baseline visual acuity, less baseline suppression, less anisometropia, and anisometropia due to astigmatism. Better outcome stereoacuity and BF score were associated with better baseline stereoacuity and BF score, more improvement in visual acuity, less anisometropia, and anisometropia due to astigmatism. Children aged 3-6 years who recovered normal visual acuity with dichoptic treatment had better stereoacuity and BF score outcomes than those with residual amblyopia. Conclusions Dichoptic therapy is an effective amblyopia treatment. Although there was no substantive advantage in promoting binocular function, stereoacuity outcomes were similar to those previously reported for patching and Bangerter filters.

Amblyopia is a form of visual cortical impairment that arises from abnormal visual experience early in life. Most often, amblyopia is a unilateral visual impairment that can develop as a result of strabismus, anisometropia, or a combination of these conditions that result in discordant binocular experience. Characterized by reduced visual acuity and impaired binocular function, amblyopia places a substantial burden on the developing child. Although frontline treatment with glasses and patching can improve visual acuity, residual amblyopia remains for most children. Newer binocular-based therapies can elicit rapid recovery of visual acuity and may also improve stereoacuity in some children. Nevertheless, for both treatment modalities full recovery is elusive, recurrence of amblyopia is common, and improvements are negligible when treatment is administered at older ages. Insights derived from animal models about the factors that govern neural plasticity have been leveraged to develop innovative treatments for amblyopia. These novel therapies exhibit efficacy to promote recovery, and some are effective even at ages when conventional treatments fail to yield benefit. Approaches for enhancing visual system plasticity and promoting recovery from amblyopia include altering the balance between excitatory and inhibitory mechanisms, reversing the accumulation of proteins that inhibit plasticity, and harnessing the principles of metaplasticity. Although these therapies have exhibited promising results in animal models, their safety and ability to remediate amblyopia need to be evaluated in humans.

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.

Purpose: The purpose of this study was to assess motion-defined form perception, including the association with clinical and sensory factors that may drive performance, in each eye of children with deprivation amblyopia due to unilateral cataract. Methods: Coherence thresholds for orientation discrimination of motion-defined form were measured using a staircase procedure in 30 children with deprivation amblyopia and 59 age-matched controls. Visual acuity, stereoacuity, fusion, and interocular suppression were also measured. Fixation stability and fellow-eye global motion thresholds were measured in a subset of children. Results: Motion-defined form coherence thresholds were elevated in 90% of children with deprivation amblyopia when viewing with the amblyopic eye and in 40% when viewing with the fellow eye. The deficit was similar in children with a cataract that had been visually significant at birth (congenital) and in children for whom the cataract appeared later in infancy or childhood (developmental). Poorer motion-defined form perception in amblyopic eyes was associated with poorer visual acuity, poorer binocular function, greater interocular suppression, and the presence of nystagmus. Fellow-eye deficits were not associated with any of these factors, but a temporo-nasal asymmetry for global motion perception in favor of nasalward motion suggested a general disruption in motion perception. Conclusions: Deficits in motion-defined form perception are common in children with deprivation amblyopia and may reflect a problem in motion processing that relies on binocular mechanisms.

Background We developed and tested a dichoptic treatment designed for younger children that can be viewed freely and involves a dichoptic manipulation of a popular animation series that enables contrast-rebalancing without disrupting fusion. Our aim was to assess whether this novel amblyopia treatment is superior to patching in children aged 3-5 years. Methods A total of 34 children with amblyopia were randomly assigned to contrast-rebalanced dichoptic cartoons (4 hours/week) or patching (14 hours/week) for 2 weeks. Children in the cartoon group continued watching cartoons for an additional 2 weeks. Designed to target the youngest and most treatable children, the dichoptic cartoons presented the entire scene to the amblyopic eye at 100% contrast, while the fellow eye view was presented at reduced contrast with the main character omitted. Best-corrected visual acuity (BCVA), stereoacuity, suppression, and manual dexterity were measured at each visit. Results After 2 weeks, improvement in amblyopic eye BCVA was greater for dichoptic treatment than for patching, with a mean improvement of 0.11 ± 0.08 versus 0.06 ± 0.09 logMAR, respectively (P = 0.04). Stereoacuity, suppression, and manual dexterity did not improve significantly more in the dichoptic group than the patching group at 2 weeks. After 4 weeks of dichoptic cartoon treatment, mean visual acuity improvement in the dichoptic group was 0.16 logMAR (95% CI, 0.10-0.21). Conclusions In our study cohort, a contrast-rebalanced dichoptic cartoon was more effective than patching in treating childhood amblyopia after 2 weeks. Dichoptic cartoons that rebalance contrast to overcome suppression provide an additional treatment option for amblyopia in young children.

SIGNIFICANCE:Amblyopic children read 25% slower than their peers during binocular silent reading.PURPOSE:We compared binocular reading to fellow eye reading to determine whether slow reading in amblyopic children is due to binocular inhibition; that is, the amblyopic eye is interfering during binocular reading.METHODS:In a cross-sectional study, 38 children with amblyopia and 36 age-similar control children who completed grades 1 to 6 were enrolled. Children silently read grade-appropriate paragraphs during binocular reading and fellow eye reading while wearing ReadAlyzer eye-tracking goggles (Compevo AB, Stockholm, Sweden). Reading rate, number of forward saccades, number of regressive saccades, and fixation duration were analyzed between groups and between viewing conditions. We also examined whether sensory factors (amblyopia severity, stereoacuity, suppression) were related to slow reading.RESULTS:For amblyopic children, binocular reading versus fellow eye reading did not differ for reading rate (176 ± 60 vs. 173 ± 53 words per minute, P = .69), number of forward saccades (104 ± 35 vs. 97 ± 33 saccades/100 words, P = .18), number of regressive saccades (21 ± 15 vs. 22 ± 13 saccades/100 words, P = .75), or fixation duration (0.31 ± 0.06 vs. 0.32 ± 0.07 seconds, P = .44). As expected, amblyopic children had a slower reading rate and more forward saccades than control children during binocular reading and fellow eye reading. Slow reading was not related to any sensory factors.CONCLUSIONS:Binocular reading did not differ from fellow eye reading in amblyopic children. Thus, binocular inhibition is unlikely to play a role in slow binocular reading and is instead a fellow eye deficit that emerges from a disruption in binocular visual experience during development.