Refractive features and amblyopia in Duane's Retraction Syndrome: A review of the 582 patients / Características refractivas y ambliopía en el síndrome de retracción de Duane: una revisión de los 582 pacientes

Purpose: To report the visual and refractive characteristics and the prevalence of amblyopia in patients with different types of Duane's Retraction Syndrome (DRS). Method: This retrospective study was performed on hospital records of 582 DRS patients at Farabi Hospital, Iran, from 2012 to March 2022. Results: The mean age of patients was 19.4 ± 11.9 (range, 3–70) years [335 (57.6 %) females and 247 (42.4 %) males (P < .001)]. DRS type I, II, III, and IV were presented in 347 (59.6 %), 148 (25.4 %), 82 (14.1 %), and 5 (0.9 %) patients, respectively. There were 530 (91.1 %) patients with unilateral and 52 (8.9 %) with bilateral involvement. In the unilateral patients, the DRS eyes' corrected distance visual acuity (CDVA) and astigmatism were significantly worse than the Non-DRS Eyes (P < .001). The mean amount of all refractive and visual parameters in bilateral patients' right or left eyes was significantly lower than in unilateral patients' non-DRS eyes (all P < .05). Anisometropia was observed in 75(12.9 %) of the patients. Amblyopia was observed in 18.5 % (98 patients) and 36.5 % (19 patients) of unilateral and bilateral DRS patients, respectively (P < .001). In unilateral patients, amblyopia was found in 57 (16.4 %) patients with Type I, 22 (14.9 %) patients with Type II, 16 (19.5 %) patients with Type III, and 3 (60 %) patients with Type IV. Forty-four (37.6 %) of patients with amblyopia had anisometropia. Conclusion: This large-scale study indicates that DRS types differ in terms of refractive error, visual acuity, and the prevalence of amblyopia and anisometropia. Clinicians should be aware of the clinical features associated with different types of DRS.(AU)

Motion-Defined Form Perception in Deprivation Amblyopia.

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.

Peripheral Binocular Imbalance in Anisometropic and Strabismic Amblyopia.

Purpose: Individuals with amblyopia experience central vision deficits, including loss of visual acuity, binocular vision, and stereopsis. In this study, we examine the differences in peripheral binocular imbalance in children with anisometropic amblyopia, strabismic amblyopia, and typical binocular vision to determine if there are systematic patterns of deficits across the visual field. Methods: This prospective cohort study recruited 12 participants with anisometropic amblyopia, 10 with strabismic amblyopia, and 10 typically sighted controls (age range, 5-18 years). Binocular imbalance was tested at 0°, 4°, and 8° eccentricities (4 angular locations each) using band-pass filtered Auckland optotypes (5 cycles per optotype) dichoptically presented with differing contrast to each eye. The interocular contrast ratio was adjusted until the participant reported each optotype with equal frequency. Results: Participants with anisometropic and strabismic amblyopia had a more balanced contrast ratio, or decreased binocular imbalance, at 4° and 8° eccentricities as compared with central vision. Participants with strabismic amblyopia had significantly more binocular imbalance in the periphery as compared with individuals with anisometropic amblyopia or controls. A linear mixed effects model showed a main effect for strabismic amblyopia and eccentricity on binocular imbalance across the visual field. Conclusions: There is evidence of decreased binocularity deficits, or interocular suppression, in the periphery in anisometropic and strabismic amblyopia as compared with controls. Notably, those with strabismic amblyopia exhibited more significant peripheral binocular imbalance. These variations in binocularity across the visual field among different amblyopia subtypes may necessitate tailored approaches for dichoptic treatment.

Reduced Monocular Luminance Promotes Fusion But Not Mixed Perception in Amblyopia.

Purpose: The purpose of this study was to understand how monocular luminance reduction affects binocular balance and examine whether it differentially influences fusion and mixed perception in amblyopia. Methods: Twenty-three normally sighted observers and 12 adults with amblyopia participated in this study. A novel binocular rivalry task was used to measure the phase duration of four perceptual responses (right- and left-tilts, fusion, and mixed perception) before and after a neutral density (ND) filter was applied at various levels to the dominant eye (DE) of controls and the fellow eye (FE) of patients with amblyopia. Phase durations were analyzed to assess whether the duration of fusion or mixed perception shifted after monocular luminance reduction. Moreover, we quantified ocular dominance and adjusted monocular contrast and luminance separately to investigate the relationship between changes in ocular dominance induced by the two manipulations. Results: In line with previous studies, binocular balance shifted in favor of the brighter eye in both normal adults and patients with amblyopia. As a function of the ND filter's density, the duration of fusion and mixed perception decreased in normal controls, whereas that of fusion but not mixed perception increased significantly in patients with amblyopia. In addition, changes in binocular balance from luminance reduction were more significant in more balanced amblyopes or normal observers. Furthermore, shifts in binocular balance after contrast and luminance modulation were correlated in both normal and amblyopic observers. Conclusions: The duration of fusion but not mixed perception increased in amblyopia after monocular luminance reduction in the FE. Moreover, our findings demonstrate that changes in ocular dominance from contrast-modulation and luminance-modulation are correlated in both normal and amblyopic observers.

Management of Contact Lenses and Visual Development in Pediatric Aphakia.

Congenital cataract is among the main causes of treatable vision loss in childhood. The first weeks and months of life are a critical time for the development of vision. Therefore, early cataract surgery and effective multifaceted treatment of the resulting aphakia in the early stages of life are of great value for the management of vision development. Among the treatment models, contact lenses (CL) have an important place in infancy and early childhood up to the age of 2 years. Although good visual gains were not considered very likely, especially in unilateral aphakia, important steps have been taken in the treatment of pediatric aphakia thanks to the surgical techniques developed over time and the increasing experience with optical correction systems, especially CLs. This review examines current developments in the types of CL used in pediatric aphakia, their application features, comparison with other optical systems, the features of amblyopia treatment in the presence of CL, and the results obtained with family compliance to CL wear and occlusion therapy in the light of existing studies.

Multifaceted Interactions of Stereoacuity, Inter-Ocular Suppression, and Fixation Eye Movement Abnormalities in Amblyopia and Strabismus.

Purpose: Amblyopic and strabismus subjects experience inter-ocular suppression, impaired stereoacuity, and increased fixation instability. The purpose of the study was to investigate factors affecting suppression and stereoacuity and examine their relationship to fixation eye movement (FEM) abnormalities. Methods: We recruited 14 controls and 46 amblyopic subjects (anisometropic = 18, strabismic = 14, and mixed = 14) and 11 subjects with strabismus without amblyopia. We utilized the dichoptic motion coherence test to quantify suppression, and stereoacuity was assessed using the Titmus Fly test. We recorded FEMs using high-resolution video-oculography and classified subjects that did not have nystagmus (n = 27) versus those with nystagmus (n = 32; fusion maldevelopment nystagmus [FMN], n = 10) and nystagmus that did not meet the criteria of FMN (n = 20). We also recorded FEMs under dichoptic viewing (DcV) at varied fellow eye (FE) contrasts and computed the amplitude and velocity of the fast and slow FEMs and vergence instability. Results: Inter-ocular suppression and stereoacuity deficits were closely correlated with an amblyopic eye (AE), visual acuity, and strabismus angle. Subjects with nystagmus displayed more pronounced stereoacuity deficits than those without nystagmus. Strabismic subjects with and without amblyopia, who demonstrated a fixation switch at 100% FE contrast, had lower inter-ocular suppression than subjects lacking a fixation switch under DcV. Amplitude of fast FEMs and velocity of slow FEMs, and vergence instability were increased as the FE contrast was lowered in both amblyopic and strabismic subjects. Conclusions: The current study highlights the intricate relationships between AE visual acuity, eye deviation, and FEM abnormalities on suppression and stereoacuity deficits and underscores the need to evaluate FEM abnormalities while assessing dichoptic treatment outcomes.

Effects of Monocular Flicker on Binocular Imbalance in Amblyopic and Nonamblyopic Adults.

Purpose: This study aimed to evaluate the effects of monocular flicker stimulation on binocular imbalance in both amblyopic and nonamblyopic adults. Methods: Seven amblyopic patients (28.3 ± 3.3 years; four females) and seven normally sighted participants (27.3 ± 4.1 years; five females) participated in the study. We used liquid crystal spectacles to create externally-generated monocular flicker (4, 7, 10, 15, or 20 Hz) and used the metric of log balance point (logBP) to determine whether imposed flicker could change the eyes' equilibrium interocular contrast ratio. Flicker was applied to either the fellow eye vs. the amblyopic eye or dominant eye (DE) vs. non-DE (non-DE) of amblyopic and nonamblyopic participants, respectively. We defined a logBP of 0 to indicate complete binocular balance and an increase in logBP relative to baseline to indicate a relative strengthening of the non-DE or amblyopic eye. Results: Monocular flicker applied to the DE or fellow eye increased logBP, whereas when applied to the non-DE or amblyopic eye, reduced the logBP. These effects were more pronounced at low temporal frequencies than that at high temporal frequencies. The interaction between eye and temporal frequency was significant in both normals, F(4, 24) = 58.082, P < 0.001, η2 = 0.906, and amblyopes, F(1.923, 11.538) = 60.555, P < 0.001, η2 = 0.91. Conclusions: Monocular flicker diminishes the contribution of the flickered eye in binocular combination, resulting in a relative dominance of the nonflickered eye in interocular interactions. Furthermore, a more pronounced temporally modulated effect was observed at lower temporal frequencies.

Association of household language and vision screening among children in the United States.

The American Academy of Pediatrics recommends annual testing in children beginning at 3 years of age to detect vision problems and prevent amblyopia. However, rates of vision testing in children from non-English primary language (NEPL) households are not well delineated. This study analyzed the 2018-2020 National Survey of Children's Health to examine patterns and predictors of vision testing among children from NEPL households. In this nationally representative cohort of 89,697 children 3-17 years of age, 70.9% of children received vision testing during the previous 12 months. Children from non-English-speaking households were less likely to undergo vision testing (64.3% vs 72.0%; aOR [95% CI] = 0.83 [0.72-0.95], P = 0.008). Decreased vision testing among children from NEPL households was driven by lower rates of testing at school (16.1% vs 21.0%; 0.72 [0.57-0.89], P = 0.009) or from an ophthalmologist or optometrist (49.0% vs 54.0%; 0.72 [0.61-0.85], P = 0.0004), whereas children from NEPL households were more likely to receive vision testing at health clinics (14.4% vs 3.1%; 3.25 [2.40-4.39], P < 0.0001). No differences were observed in rates of testing by a pediatrician (41.1% vs 44.0%; 1.05 [0.89-1.23], P = 0.69). Interventions to improve language services and health literacy are warranted to increase rates of vision testing among children from NEPL households.

Treatment rate of strabismus and amblyopia is associated with the location of pediatric ophthalmologists in the United States.

PURPOSE: To determine whether the geographic density of pediatric ophthalmologists is associated with the rate of children treated for strabismus and amblyopia. METHODS: This cross-sectional study included children treated for strabismus and amblyopia 0-17 years of age with commercial insurance who were included in the Vision and Eye Health Surveillance System. Additionally, pediatric ophthalmologists by state were determined using the American Association for Pediatric Ophthalmology and Strabismus website. Unadjusted linear regression was used to compare the geographic density of pediatric ophthalmologists and the rate of children treated for strabismus and amblyopia by state in 2016. This was repeated using multivariable linear regression, controlling for race, poverty, non-English-speaking children, and insurance coverage for children by state. RESULTS: New York and Mississippi had the highest and lowest rates of treatment of strabismus and amblyopia, with 3.97 and 0.83 children treated per 100 children, respectively. The geographic density of pediatric ophthalmologists was associated with the rate of children treated for strabismus and amblyopia in unadjusted analyses (ß = 0.62, P < 0.001). Further, the geographic density of pediatric ophthalmologists was associated with the rate of children treated for strabismus and amblyopia in adjusted analyses (ß = 0.61, P < 0.001). CONCLUSIONS: The geographic density of pediatric ophthalmologists by state was positively associated with the rate of children treated for strabismus and amblyopia.

Impact of active vision therapy compared to conventional patching therapy on visual acuity and stereoacuity in children with amblyopia

Purpose To compare improvements in visual acuity (VA) and stereoacuity between active vision therapy (AVT) and conventional patching therapy in children with amblyopia. Methods This study included 65 children aged 5 to 16 years (mean age±SD, 11.00±3.29 years) with unilateral amblyopia. Among them, 31 children underwent active vision therapy (AVT group), and 34 children underwent conventional patching therapy (patching group). AVT group underwent three sequential phases of AVT: Monocular phase (pursuit, saccades, fixation, visuomotor, eye-hand coordination, and central peripheral activities), biocular phase (diplopia awareness, antisuppression, monocular fixation in a binocular field, accommodative activities, bilateral integration, and fine motor activities) and binocular phase (fusion and stereopsis). Patching group patched their fellow eyes as per guidelines by Pediatric Eye Disease Investigator Group. Best-corrected monocular VA and stereoacuity were measured at baseline and after three months of therapy in both groups. Results There were significant improvements in the mean acuities in amblyopic eye (AE) in both AVT (0.32±0.11 logMAR, p <0.001) and patching groups (0.27±0.19 logMAR, p ˂ 0.001). However, there was no significant difference in mean acuity gains in AE between AVT and patching groups (p = 0.059). Mean gains in stereoacuities (log seconds of arc) were statistically significant in both AVT (0.81±0.34, p < 0.001) and patching groups (0.32±0.34, p < 0.001). The stereoacuity gain in the AVT group was significantly higher compared to patching group (p < 0.001). Conclusion Active vision therapy had a better impact than conventional patching therapy in terms of improvement of stereoacuity but not in terms of VA when used for treating children with amblyopia. (AU)

[The effect of pleoptic treatment on the stability of visual fixation in children and adolescents with amblyopia of various degrees]. / Vliyanie pleopticheskogo lecheniya na stabil'nost' zritel'noi fiksatsii u detei i podrostkov s ambliopiei po dannym mikroperimetrii.

PURPOSE: This study assesses the effect of pleoptic treatment on the stability of visual fixation in children and adolescents with amblyopia of various degrees. MATERIAL AND METHODS: The effect of the treatment in 35 children (35 eyes) with amblyopia of various degrees was evaluated using the MP-1 Microperimeter. The stability was determined by two criteria - number of fixation point hits in the 2° zone and the width of the field of fixation. Children underwent a standard course of treatment. RESULTS: There was an improvement in the stability of visual fixation after treatment. The number of fixation point hits in the 2° zone increased from 44.8±4.1% to 52.6±3.8%. At the same time, the width of the field of fixation after treatment decreased from 6.5±0.7° to 5.2±0.5°. Visual acuity with correction in children with amblyopia correlates with the number of fixation point hits in the 2° zone (direct high correlation "+0.7") and width of the field of fixation (inverse high correlation "-0.7") both before and after the treatment. CONCLUSION: Stabilization of visual fixation was observed in patients with amblyopia of varying degrees after the pleoptic treatment.

Predicting myopic changes in children wearing glasses using the Plusoptix photoscreener.

INTRODUCTION: With high increase in myopia prevalence, we aimed to assess whether Plusoptix_A09 can be used in myopic children over spectacles to predict visual acuity (VA) and myopic refraction changes. METHODS: Myopic children underwent a complete ophthalmological examination. Plusoptix_A09 was performed over spectacles. VA changes, refraction changes and time since previous glasses prescription, were determined. Age, current or past history of amblyopia, presence of strabismus and self-perception of VA changes were registered. RESULTS: In total, 199 patients were included. Spherical power (SP) and spherical equivalent (SE) measured by Plusoptix_A09 over spectacles predicted both VA changes (p < 0.001) and refraction changes (p < 0.001). Values of SP < - 0.06D or SE < - 0.22D indicated a VA decrease (AUC > 0.9, p < 0.01) for sensitivity and specificity of 85.1%, 82.1% and 82.6%, 83.3%, respectively. Age and ophthalmological comorbidities did not influence Plusoptix_A09 measurements (p > 0.05). Plusoptix_A09 over spectacles was a stronger predictor of VA changes when compared to children's self-perception, either in 4-9-year-old patients (p < 0.001 versus p = 0.628) and in 10-18-year-old children (OR < = 0.066 versus OR = 0.190). A decrease in SP and SE of - 0.10D in Plusoptix_A09 predicted a myopia progression of - 0.04D and - 0.05D, respectively. CONCLUSION/RELEVANCE: This study unveiled new features for the Plusoptix, a worldwide available photoscreener used in amblyopia screening. When Plusoptix is performed in children with their glasses on, it can rapidly predict myopia progression. For each decrease of - 0.10D in Plusoptix, a myopia progression of -0.05D is expected. Moreover, Plusoptix is more reliable than children's self-perception of visual acuity changes, making it a useful tool either in primary care or ophthalmology practice.

Pattern electroretinography response in amblyopic adults.

INTRODUCTION: Amblyopia is generally a unilateral disorder, defined by at least a difference of two lines of visual acuity between both eyes with the best-corrected visual acuity, a decrease in contrast sensitivity, and a decrease in stereopsis. Pattern electroretinogram (PERG) is a noninvasive technique that provides a retinal biopotential and is a highly sensitive indicator of changes in the macular area. Our aim was to evaluate if there are differences in the retinal response of an amblyopic eye compared with a normal eye (NE). METHODS: We evaluated twenty-four adult volunteers, twelve amblyopes (mean 43.42 ± 12.72 years old), and twelve subjects with NE (mean 35.58 ± 12.85 years old). None of the subjects in the two groups had comorbidities. A complete optometric examination was performed including parameters such as visual acuity (VA) by far and near with ETDRS chart, eye alignment with cover test, and evaluation of retinal cells response with PERG. RESULTS: The refractive error found in the NE group of subjects had a mean of - 0.95 ± 1.65D, while the amblyopic group showed a mean of - 2.03 ± 4.29D. The VA in amblyopic eyes had a mean of 0.38 ± 0.20 logMAR. Analyzing PERG data, we observed significant differences in the P50-N95 amplitudes of the amblyopic group compared with the NE group (p < 0.0001-amblyopic eye vs. NE; p = 0.039-fellow eye vs. NE). DISCUSSION: These findings suggest that amblyopic patients may also present other impairments beyond the visual cortex. PERGs seem to be an important complementary examination in the diagnosis of other impairments in amblyopia.

Prevalence and causes of ocular disorders and visual impairment among preterm children in Ethiopia.

OBJECTIVE: The aim of this study was to determine the prevalence, causes of ocular disorders and visual impairment among preterm children previously admitted to neonatal intensive care units in Addis Ababa, Ethiopia. METHODS AND ANALYSIS: A prospective screening survey was conducted from February to June 2019 at the paediatric eye clinic of Menelik II Hospital. Children who were preterm at birth and who attended the eye clinic were included in the study. Data on demographic and neonatal characteristics, neonatal and maternal comorbidities and ocular disorders were collected. OR and univariate analysis were used to identify predictors of ocular diseases and visual impairment. RESULTS: There were 222 children included in the study with a mean age at presentation of 2.62 years (range 2.08-6.38 years), mean gestational age 34.11 weeks (range 30-36) weeks and mean birth weight 1941.72 g (range 953-3500 g). Nearly two-thirds had ocular disorders with refractive error (51.8%), strabismus (11.3%) and a history of retinopathy of prematurity (ROP) (7.2%) being more common. One-fourth of the children had visual impairment, and the prevalence of amblyopia was 40.1%. Uncorrected refractive errors, strabismus and ROP were causes for visual impairment. CONCLUSION: Visual impairment and amblyopia are common in Ethiopia. There is a need to develop a screening protocol for ocular disorders for preterm children to enhance early detection and prevention of childhood visual impairment.

Amblyopia Care Trends Following Widespread Photoscreener Adoption.

Importance: Amblyopia can result in permanent vision loss if not properly treated before age 7 years. In 2017, the US Preventive Services Task Force recommended that vision screening should occur at least once in all children aged 3 to 5 years to detect amblyopia. Objective: To understand trends and factors associated with screening, referral, or diagnosis of amblyopia before and after photoscreening expansion across a relatively large health care system in late 2017. Design, Setting, and Participants: This is a retrospective cohort study of electronic health record data from patients with a well child care visit at approximately age 3 years (ages 2.75-3.25 years) in a relatively large, multispecialty group practice in Northern California and linked census data between 2015 and 2022. Data were extracted and analyzed from October 2022 through August 2023. Exposures: Patient sex, race and ethnicity, immunization records, previous well child care visits, and census-level median household income. Main Outcomes and Measures: Vision screening, pediatric ophthalmology referral, or amblyopia diagnosis, compared using adjusted odds ratios (AORs). Results: The study included 2015-2017 data from 23 246 patients aged 3 years with at least 1 well child care visit (11 206 [48.2%] female) compared with 2018-2022 postexpansion data from 34 281 patients (16 517 [48.2%] female). The screening rate increased from 5.7% (424 of 7505) in 2015 to 72.1% (4578 of 6354) in 2022. The referral rate increased from 17.0% (1279 of 7505) in 2015 to 23.6% (1836 of 7792) in 2018. The diagnosis rate was 2.7% (200 of 7505) in 2015, peaked at 3.4% (263 of 7792) in 2018, and decreased to 1.4% (88 of 6354) in 2022. Compared with White patients, patients who were Asian, Black, or Hispanic were less likely to be screened (Asian: AOR, 0.80; 95% CI, 0.72-0.88; Black: AOR, 0.71; 95% CI, 0.53-0.96; Hispanic: AOR, 0.88; 95% CI, 0.80-0.97). Compared with White patients, patients who were Asian or Hispanic were more likely to be referred (Asian: AOR, 1.49; 95% CI, 1.36-1.62; Hispanic: AOR, 1.32; 95% CI, 1.18-1.48) and were more likely to be diagnosed (Asian: AOR, 1.29; 95% CI, 1.07-1.56; Hispanic: AOR, 1.67; 95% CI, 1.33-2.11). Conclusions and Relevance: In this study, increased availability of photoscreeners was associated with an increase in overall rates of vision screening for children aged 3 years in a relatively large health care system. Given that US rates of visual impairment are predicted to increase, additional targeted interventions would be needed to address remaining disparities in amblyopia care along patient- and clinician-level factors.

Flash Suppression Reveals an Additional Nonvisual Extrastriate Contribution for Amblyopic Suppression.

Purpose: A growing body of evidence suggests that anomalous binocular interactions underlie the deficits in amblyopia, but their nature and neural basis are still not fully understood. Methods: We examined the behavioral and neural correlates of interocular suppression in 13 adult amblyopes and 13 matched controls using a flash suppression paradigm while recording steady-state visual evoked potentials. The strength of suppression was manipulated by changing the contrast (10%, 20%, 30%, or 100%) of the flash stimulus, or the suppressor, presented either in the dominant (fellow) or nondominant (amblyopic) eye. Results: At the behavioral level, interocular suppression in normal observers was found, regardless of the eye origin of the flash onset. However, the pattern of suppression in the amblyopes was not symmetric, meaning that the suppression from the dominant eye was stronger, supporting a putative chronic suppression of the amblyopic eye. Interestingly, the amblyopic eye was able to suppress the dominant eye but only at the highest contrast level. At the electrophysiology level, suppression of the steady-state visual evoked potential responses in both groups in all conditions was similar over the occipital region, but differed over the frontal region. Conclusions: Our findings suggest that, although suppression in amblyopia involves an imbalanced interaction between the inputs to the two eyes in the visual cortex, there is also involvement of nonvisual extrastriate areas.