Risk factors for treatment failure of anisometropic amblyopia

High-adherence dichoptic treatment versus patching in anisometropic and small angle strabismus amblyopia: a randomized controlled trial

PURPOSE

To compare the effectiveness and safety of a novel binocular eye-tracking-based-home-treatment (CureSight) to patching for the treatment of amblyopia.

DESIGN

Prospective, masked, randomized controlled noninferiority trial.

SETTING

Multicenter, multinational, home treatment.

PARTICIPANTS

One hundred forty-nine children 4 to < 9 years with anisometropic, small-angle strabismic, or mixed-mechanism amblyopia were randomized to either binocular treatment (n=75) or patching (n=74).

INTERVENTIONS

The binocular treatment group used the CureSight system for 90 min/day, 5 days/week for 16 weeks (120 hours). The patching group received 2-hour patching 7 days/week (224 hours).

MAIN OUTCOME MEASURES

The primary outcome was the mean improvement from baseline in amblyopic eye visual acuity (VA) to week 16 in both study groups (non-inferiority of ≤0.10 logarithm of the minimum angle of resolution [logMAR]). Other outcomes included changes in stereoacuity and binocular VA from baseline to week 16.

RESULTS

The mean improvement from baseline at week 16 in the binocular treatment group was noninferior to patching group improvement in the modified intent-to-treat (mITT) dataset (LS mean difference between groups in improvement from baseline: 0.034 logMAR (95% CI -0.009 to 0.076)). In the per-protocol (PP) dataset, the mean improvement from baseline at week 16 in the binocular treatment group was superior to patching group improvement (LS mean difference between groups in improvement from baseline: 0.05 logMAR ([95% CI; 0.007 to 0.097]). At week 16, both groups showed significant median improvement in stereoacuity, with no significant between-group difference in the magnitude of improvement in both the mITT and the PP datasets. Binocular VA was also improved in both groups (p<0.0001). Median adherence in the mITT binocular treatment group (94.0%) was also significantly higher than in the patching group (83.9%; p=0.0038).

CONCLUSIONS

Binocular, eye-tracking-based amblyopia home treatment is at least as effective as patching.

Pediatric refractive surgery: current opinion in ophthalmology

PURPOSE OF REVIEW

Pediatric refractive surgery has been growing at a steady pace since its introduction in the early 1980 s. This article will review common laser refractive surgeries performed on pediatric patients along with controversies regarding the practice.

RECENT FINDINGS

Pediatric refractive surgery is reserved for a small population of children who fail amblyopic treatment due to high anisometropic refractive errors. Publications over the years have treated these children with various types of laser refractive surgery.

SUMMARY

Laser pediatric refractive surgery appears to be well tolerated and effective for the population of children that need it. It provides an alternative for anisometropic amblyopia treatment for children who would have otherwise not been able to improve their vision.

An Eye-Tracking-Based Dichoptic Home Treatment for Amblyopia: A Multicenter Randomized Clinical Trial

PURPOSE

Comparing visual outcomes after use of a novel binocular eye-tracking-based home treatment (CureSight; NovaSight, Ltd) with patching.

DESIGN

Prospective, multicenter, randomized, masked, controlled, noninferiority pivotal trial.

PARTICIPANTS

One hundred three children 4 to < 9 years with anisometropic, small-angle strabismic or mixed-mechanism amblyopia were randomized 1:1 to either CureSight treatment or patching.

METHODS

The CureSight treatment uses combined anaglyph glasses and an eye tracker to induce real-time blur around the fellow eye fovea in dichoptic streamed video content. Participants used the device for 90 minutes/day, 5 days/week for 16 weeks (120 hours). The patching group received 2 hours of patching 7 days/week (224 hours). The prespecified noninferiority margin was 1 line.

MAIN OUTCOME MEASURES

The primary outcome was the improvement in the amblyopic eye visual acuity (VA), modeled with a repeated measures analysis of covariance. Secondary outcomes included stereoacuity, binocular VA, and treatment adherence rates, analyzed by a 1-sample Wilcoxon test within each group and a 2-sample Wilcoxon test comparing groups. Safety outcomes included the frequency and severity of study-related adverse events (AEs).

RESULTS

CureSight group VA improvement was found to be noninferior to patching group improvement (0.28 ± 0.13 logarithm of the minimum angle of resolution [logMAR] [P < 0.0001] and 0.23 ± 0.14 logMAR [P < 0.0001], respectively; 90% confidence interval [CI] of difference, -0.008 to 0.076). Stereoacuity improvement of 0.40 log arcseconds (P < 0.0001) and improved binocular VA (0.13 logMAR; P < 0.0001) were observed in the binocular treatment group, with similar improvements in the patching group in stereoacuity (0.40 log arcseconds; P < 0.0001) and binocular VA (0.09 logMAR; P < 0.0001), with no significant difference between improvements in the 2 groups in either stereoacuity (difference, 0; 95% CI, -0.27 to -0.27; P = 0.76) or binocular VA (difference, 0.041; 95% CI, -0.002 to 0.085; P = 0.07). The binocular treatment group had a significantly higher adherence than the patching group (91% vs. 83%; 95% CI, -4.0% to 21%; P = 0.011). No serious AEs were found.

CONCLUSIONS

Binocular treatment was well tolerated and noninferior to patching in amblyopic children 4 to < 9 years of age. High adherence may provide an alternative treatment option for amblyopia.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Ocular and visual perceptive factors associated with treatment outcomes in patients with anisometropic amblyopia

BACKGROUND

The aim of this observational study was to identify ocular and visual perceptive risk factors related to treatment results following refractive correction and patching in children with anisometropic amblyopia, who were between the ages of 4 to 14 years old.

METHODS

One-hundred and two children with newly diagnosed anisometropic amblyopia were recruited. Successful treatment of amblyopia was defined as the final best corrected visual acuity (BCVA) better than or equal to 0.1 logMAR and amblyopic eye BCVA within 1 line of the sound eye BCVA by the end of the treatment period. BCVA, cycloplegic refraction, stereoacuity, perceptual eye position (PEP) and interocular suppression were measured.

RESULTS

Of these patients, 45.10% achieved successful treatment of amblyopia after refractive correction and patching for 10.5 months. The mean age was not significantly different between patients who were successfully and unsuccessfully treated (5.50 ± 1.59 years vs 6.14 ± 2.19 years, respectively). Patients who failed treatment had significantly larger interocular difference of BCVA at the time of initial treatment (successful group: 0.33 ± 0.29 logMAR, unsuccessful group: 0.65 ± 0.35 logMAR) and after refractive adaptation (successful group: 0.15 ± 0.13 logMAR, unsuccessful group: 0.42 ± 0.35 logMAR). They also had higher spherical equivalent (SE) of amblyopic eyes (successful group: 3.08 ± 3.61 D, unsuccessful group: 5.27 ± 3.38 D), bigger interocular difference of SE (successful group: 0.94 ± 2.71 D, unsuccessful group: 3.09 ± 3.05 D), worse stereoacuity (successful group: 2.32 ± 0.37 log seconds of arc, unsuccessful group: 2.75 ± 0.32 log seconds of arc), larger vertical PEP deviation (successful group: 6.41 ± 6.08 pixel, unsuccessful group: 19.07 ± 24.96 pixel) and deeper interocular suppression (successful group: 21.7 ± 19.7%, unsuccessful group: 37.8 ± 27.1%) than those of successfully treated patients. The most influential treatment failure risk factors were larger vertical PEP deviation [adjusted odds ratio (OR) (95% confidence interval) 1.12 (1.02-1.22)] and worse stereoacuity [adjusted odds ratio (OR) (95% confidence interval) 7.72 (1.50-39.85)] in multiple logistic regression analysis.

CONCLUSIONS

Larger vertical PEP deviation and worse stereoacuity were the most influential treatment failure risk factors in children with anisometropic amblyopia. The vertical PEP deviation and stereoacuity, which can reflect interocular interaction, may be useful in predicting the response to therapy.

Anterior Chamber Iris-Fixated Phakic Intraocular Lens Implantation for Treatment of High Anisometropia in Children: Long-term Results

PURPOSE

To evaluate the long-term efficacy of anterior chamber iris-fixated phakic intraocular lens (PIOL) implantation in the treatment of high myopic (> -9.00 diopters [D]) or hyperopic (> +6.00 D) anisometropia in children with intolerance to spectacles or contact lenses.

METHODS

A total of 58 children with anisometropic myopia (range: -9.25 to -18.50 diopters [D]) and 13 children with anisometropic hyperopia (range: +6.00 to +8.50 D) underwent unilateral iris-claw PIOL implantation from 2008 to 2018. The mean age was 6.7 years. The mean follow-up was 38.5 months. Target refraction was emmetropia.

RESULTS

The cycloplegic refraction (mean spherical equivalent) improved from -12.47 D (range: -9.25 to -18.50 D) to -0.73 D (range: +0.75 to -1.50 D) in myopic eyes and reduced from +7.15 D (range: +6.00 to +8.50 D) to +0.94 D (range: -0.50 to + 1.75 D) in hyperopic eyes. Eighty-four percent of eyes were corrected to within ±1.00 D of emmetropia. The mean uncorrected distance visual acuity (UDVA) improved from 1.74 ± 0.36 to 0.45 ± 0.28 logarithm of the minimum angle of resolution (logMAR) (P = .0014). The mean corrected distance visual acuity (CDVA) changed from 0.68 ± 0.32 to 0.27 ± 0.15 logMAR (P = .02179). The safety index was 2.18 and the efficacy index was 1.51. The mean pre-operative endothelial cell count of 2,874.7 cells/mm² changed to 2,685.3 cells/mm² at 2 to 6 years postoperatively. Binocular vision quality was improved in 55 patients. No patient had serious complications or lost any Snellen lines of CDVA.

CONCLUSIONS

Iris-fixated PIOL implantation is an effective and safe method in the treatment of high anisome-tropic myopia and hyperopia and amblyopia in pediatric patients who are noncompliant with spectacles or contact lenses. [J Pediatr Ophthalmol Strabismus. 20XX;X(X):XX-XX.].

Refractive Characteristics and Related Factors of Amblyopia after Lamellar Keratoscleroplasty in Children with Limbal Dermoids

We examined the refractive characteristics and related factors of amblyopia in pediatric patients with limbal dermoids undergoing lamellar keratoscleroplasty. Forty-one children (mean age: 56.15 ± 22.47 months) were enrolled. Cycloplegic refraction, corneal topography, and anterior segment photography were performed. The corneal topographic and distribution characteristics of the refractive state were summarized, and the relationship between limbal dermoid invasion size and the refractive state was analyzed. The relationship between invasion size and amblyopia severity and the effect of clinical intervention at different times on amblyopia treatment were also analyzed. The spherical power distribution was −1.0−+10.75 D (average: +4.79 ± 3.09 D). The cylinder power was −1.25−−8.75 D (average: −4.19 ± 1.93 D). The axial range of astigmatism was 10−180° (average: 103.54 ± 58.16°). Equivalent spherical refraction was −3.88−+7.76 D (average: +2.70 ± 3.08 D). Twenty-five, fifteen, and one case had limboid dermoid invasion of the central circular zone (CCZ), paracentral annular zone (PCZ), and corneal limbus within 1 mm, respectively. Corneal topography of 39 patients showed flat, steep, and mean curvatures of 38.48 ± 2.12 D, 43.29 ± 1.97 D, and 40.70 ± 1.48 D, respectively. The mean astigmatism was 4.80 ± 2.93 D in the 3-mm optical region. Astigmatism was higher in CCZ than in PCZ invasion (p < 0.05). Postoperative visual acuity was positively correlated with patients’ age and amblyopia treatment duration (r = 0.392, p = 0.048; r = 0.488, p = 0.011), and was negatively correlated with astigmatism (r = −0.646, p < 0.001). High hyperopia and astigmatism are the dominant refractive errors in patients with limbal dermoids undergoing lamellar keratoscleroplasty.

Fixation instability, astigmatism, and lack of stereopsis as factors impeding recovery of binocular balance in amblyopia following binocular therapy

Dichoptic therapy is a promising method for improving vision in pediatric and adult patients with amblyopia. However, a systematic understanding about changes in specific visual functions and substantial variation of effect among patients is lacking. Utilizing a novel stereoscopic augmented-reality based training program, 24 pediatric and 18 adult patients were trained for 20 h along a three-month time course with a one-month post-training follow-up for pediatric patients. Changes in stereopsis, distance and near visual acuity, and contrast sensitivity for amblyopic and fellow eyes were measured, and interocular differences were analyzed. To reveal what contributes to successful dichoptic therapy, ANCOVA models were used to analyze progress, considering clinical baseline parameters as covariates that are potential requirements for amblyopic recovery. Significant and lasting improvements have been achieved in stereoacuity, interocular near visual acuity, and interocular contrast sensitivity. Importantly, astigmatism, fixation instability, and lack of stereopsis were major limiting factors for visual acuity, stereoacuity, and contrast sensitivity recovery, respectively. The results demonstrate the feasibility of treatment-efficacy prediction in certain aspects of dichoptic amblyopia therapy. Furthermore, our findings may aid in developing personalized therapeutic protocols, capable of considering individual clinical status, to help clinicians in tailoring therapy to patient profiles for better outcome.

Visual acuity increase in meridional amblyopia by exercises with moving gratings as compared to stationary gratings

The aim of the present work was to investigate the effect of a novel therapy based on pleoptic exercises combined with standard occlusion in patients with meridional amblyopia. The exercising system itself, termed focal ambient visual acuity stimulation (FAVAS), consists of sinusoidally modulated circular gratings, which were implemented as a background pattern in computer games binding the children's attention. For the assessment of therapeutic effects, we tested for the development of best-corrected visual acuity (BCVA) in patients trained with a gaming field background of moving gratings (Moving) compared to patients treated with stationary gratings (Stationary). Patients with amblyopia (caused by strabismus, refraction, or both) and astigmatism were randomly allocated to two groups, all of whom received a standard occlusion regimen. In combination with occlusion, using a crossover design, the first group (Moving-Stationary group) was alternately exercised for 10 days with a series of Moving followed by 10 days with Stationary and the second group (Stationary-Moving group) vice versa. The treatment-dependent training effect on BCVA was measured with respect to the alignment of the least vs. the most ametropic meridian in both groups. BCVA was examined using a meridionally direction-sensitive visual test inventory, and we estimated the monocular BCVA in all patients along four meridians: 0°, 45°, 90°, and 135° before and after Moving as compared to Stationary treatments. The Moving-Stationary group consisted of 17 children (34 eyes) aged 10 to 13 (average 11.6 ± 0.3) years. The Stationary-Moving group consisted of 20 children (40 eyes) aged 9 to 14 (average 12.5 ± 0.4). In both groups, visual acuity increased significantly only with Moving combined with occlusion. Thereby, the visual acuity (logMAR) along different meridians showed a statistically significant improvement induced by Moving if testing was coincident with alignment of the directional optical characters close to the most ametropic meridian in the Moving-Stationary group (0.73 ± 0.32 to 0.41 ± 0.22, p < 0.01) and also in the Stationary-Moving group (0.48 ± 0.27 to 0.33 ± 0.18, p < 0.01). Significant improvement was also induced by Moving if tested in alignment with the perpendicular orientation close to the least ametropic meridian, although with a smaller amount, in the Moving-Stationary group (0.49 ± 0.23 to 0.37 ± 0.21, p < 0.01) as well as in the Stationary-Moving group (0.33 ± 0.18 to 0.28 ± 0.16, p < 0.01). After Stationary combined with occlusion, however, there was no statistically significant improvement, regardless of the meridian. Visual training of patients with meridional amblyopia by a series of online exercises using attention-binding computer games which contained moving gratings as a background stimulus (Moving) resulted in a statistically significant improvement in visual acuity in the most refractive meridian, and to a lesser extent, in the least refractive meridian. No statistically significant improvement was achieved after the respective exercising series in the sham condition with stationary gratings (Stationary).

New treatment for amblyopia based on rules of synaptic plasticity: a randomized clinical trial

Amblyopia resulting from early deprivation of vision or defocus in one eye reflects an imbalance of input from the eyes to the visual cortex. We tested the hypothesis that asynchronous stimulation of the two eyes might induce synaptic plasticity and rebalance input. Experiments on normal adults showed that repetitive brief exposure of grating stimuli, with the onset of each stimulus delayed by 8.3 ms in one eye, results in a shift in perceptual eye dominance. Clinical studies (Clinical trial registration number: ChiCTR2100049130), using popular 3D movies with similar asynchrony between the two eyes (amblyopic eye stimulated first) to treat anisometropic amblyopia, established that just 10.5 h of conditioning over <3 weeks produced improvement that met criteria for successful treatment. The benefits of asynchronous conditioning accumulate over 20-30 45 min sessions, and are maintained for at least 2 years. Finally, we demonstrate that asynchronous binocular treatment alone is more effective than patching only. This novel treatment is popular with children and is some 50 times more efficient than patching alone.

Effect of refractive error type in the amblyopic eyes on factors for treatment success in anisometropic amblyopia

To investigate the factors for treatment success in anisometropic amblyopia according to the spherical equivalent (SE) type of amblyopic eyes. Medical records of 397 children with anisometropic amblyopia aged 3 to 12 years who presented in a secondary referral eye hospital during 2010 ~ 2016 were retrospectively reviewed. Anisometropia was defined as ≥ 1 diopter (D) difference in SE, or ≥ 1.5 D difference of cylindrical error between the eyes. According to the SE of amblyopic eyes, patients were categorized into hyperopia (SE ≥ 1D), emmetropia (− 1 < SE <  + 1) and myopia (SE ≤ − 1D) groups. Treatment success was defined as achieving interocular logMAR visual acuity difference < 0.2. Multivariate logistic regression was used to analyze the factors for treatment success. Significant factors for the amblyopia treatment success in hyperopia group (n = 270) were younger age [adjusted odds ratio (aOR) (95% confidence interval, CI) = 0.529 (0.353, 0.792)], better BCVA in amblyopic eyes at presentation [aOR (95% CI) 0.004 (0, 0.096)], longer follow-up period [aOR (95%CI) = 1.098 (1.036, 1.162)], and no previous amblyopia treatment history [aOR (95% CI) 0.059 (0.010, 0.364)]. In myopia group (n = 68), younger age [aOR (95% CI) 0.440 (0.208, 0.928)] and better BCVA in amblyopic eyes [aOR (95% CI) 0.034 (0.003, 0.469)] were associated with higher odds of treatment success. There was no significant factor for treatment success in emmetropia group (n = 59) in this population. The refractive error type of amblyopic eyes at presentation affects the factors for treatment success in anisometropic amblyopia.

Effectiveness of citicoline in pediatric patients with refractive amblyopia in Surabaya, East Java, Indonesia

OBJECTIVES

Amblyopia is a decrease of visual acuity that cannot be attributed to any structural abnormality of the eye or visual system, causing a partial or complete loss of vision due to inadequate stimulation in early life. Citicoline has been reported to improve visual acuity in amblyopic eyes as adjuvant treatment. This study was aimed to determine the effectiveness of citicoline in pediatric patients with refractive amblyopia in ophthalmology daily practices.

METHODS

This was a retrospective-descriptive study with a time limited sampling method. This study was conducted at Surabaya Eye Clinic, East Java, Indonesia, by reviewing medical records for the period of January 2018 to December 2019.

RESULTS

A total of 34 eyes were included in the study with the majority aged five years (41.2%) and six years (35.3%). The severity of amblyopia varied among patients, 21 eyes (61.76%) had mild amblyopia, seven eyes (20.59%) had moderate amblyopia, and two eyes (5.88%) had severe amblyopia. The duration of given therapy also varied, 18 eyes (52.94%) were given 3 months therapy, two eyes were given 4 months therapy, 12 eyes were given 6 months therapy, and two eyes were given 8 months therapy. Citicoline was found effective in mild and moderate amblyopia and for the duration of 3 and 6 months (p<0.05). In others group who did not showed statistically significant improvement was due to inadequate samples but clinically significant improvement was noted.

CONCLUSIONS

Citicoline therapy resulted in a clinically and statistically improvement in refractive amblyopia patients.

Effect of monocular fixation in binocular field (MFBF) on amblyopia - a pilot study comparing it with patching

54 children with anisometropic amblyopia of ages 4-15 years were included in the study - 24 children in the patching and 30 children in the MFBF group. The study ran for a period of 6 months with BCVA assessed at each visit of follow up.

In the patching group, visual acuity (VA) gain was 0.37 ± 0.26 log Mar over the course of 6 months with continuous improvement in vision across the three time points (0.20 log mar in the first month, 0.11 log Mar from month1 to 3 and 0.06 log Mar from months 3 to 6).In the Amb I Net group, visual acuity gain was 0.54 ± 0.38 log Mar over the same course of time. A continuous improvement in vision was also noted, with gains of 0.16 in the first month, 0.19 from month 1 to 3 and 0.19 from month 3 to 6. The difference in log Mar gains in VA was not statistically significant between the treatment arms and the final VA was similar (0.25 log Mar for patching and 0.18 log Mar for Amb I net). However, clinically the patching group showed 3 log MAR lines, whereas the MFBF group showed 5 log MAR lines of vision improvement at the end of therapy.

MFBF was not superior to patching as far as efficacy is concerned in anisometropic amblyopia. However, the combination of more game options to sustain interest, a shorter duration of therapy over the course of a week and software directed compliance monitoring system favors the Amb I Net system from both patient and parental perspective. Amb I Net also negated discomfort, social stigma, and parental monitoring needed with patching regimens. It can be considered as a good alternative to patching in reluctant/non - compliant children with anisometropic amblyopia. This is the first large cohort study based on this therapy.

Amblyopia therapy in Asian children: factors affecting visual outcome and parents' perception of children's attitudes towards amblyopia treatment

INTRODUCTION

Amblyopia treatment in the form of glasses and/or patching in children poses a great challenge to parents. This study aimed to assess the factors that influence visual outcome in amblyopia and children's perception towards treatment.

METHODS

180 children (aged 3.0-7.0 years) with newly diagnosed amblyopia were recruited. The effects of age, gender, type of amblyopia, treatment and compliance on visual outcome at one year were assessed. Parents completed a questionnaire on children's attitudes towards amblyopia treatment.

RESULTS

150 (83%) children with a mean age of 5.2 ± 0.8 years returned for follow-up at one year. 130 (87%) had refractive amblyopia and 20 (13%) had strabismic and refractive-strabismic amblyopia. Visual acuity (VA) of 6/9 or better in the amblyopic eye was achieved in 121 (81%) children. On multivariable analysis, poor responders were more likely to have initial VA of worse than 6/15 (relative risk [RR] 4.17, 95% confidence interval [CI] 1.58-11.00, p = 0.004), prescribed combined (glasses and patching) treatment (RR 2.83, 95% CI 1.02-7.83, p = 0.045) and poor compliance (RR 6.10, 95% CI 1.90-19.57, p = 0.002) after adjustment for age, gender and type of amblyopia. While 7% of children initially reacted poorly to treatment, 5% remained uncooperative at the first follow-up visit. Children had difficulty with schoolwork (5%), mood changes (6%) and social problems (2%) associated with treatment.

CONCLUSION

Most children with amblyopia respond well to treatment, but more care (i.e. more parental education and closer follow-up) may be needed in children who are non-compliant and have poorer initial VA.

Macular Thickness, Foveal Volume, and Choroidal Thickness in Amblyopic Eyes and Their Relationships to the Treatment Outcome

Purpose

To assess the correlations between the retinal/choroidal structure and the treatment outcomes of amblyopic children.

Methods

This study enrolled eyes with amblyopia resulting from strabismus, anisometropia, or ametropia. All patients underwent detailed eye examinations, including spectral domain optical coherence tomography (SD-OCT) scan. All of the subjects received amblyopic treatment and were divided into 2 groups after 6 months of follow-up: the recovered amblyopic group with a best-corrected visual acuity (BCVA) ≥0.8 and the persistent amblyopic group with a BCVA <0.8 on the Landolt C chart.

Results

Forty-four amblyopic children were included, of which 26 were in the recovered amblyopic group after 6 months of follow-up. The patients with strabismic anisometropic amblyopia and severe amblyopia (initial VA ≤ 0.3) were significantly predisposed to developing persistent amblyopia (P=0.049 and P < 0.001, respectively). After correcting with Littmann's formula, the thickness and volume of the parafoveal and perifoveal retinal regions in the persistent amblyopia group did not show significant differences with the recovered amblyopia group.

Conclusions

The initial severity of amblyopia and the type of amblyopia were the risk factors related to the poor outcome of amblyopic treatment. The foveal thickness, foveal volume, and choroidal thickness were not associated with the treatment outcome.

V4B implantable collamer lens versus Intacs corneal rings to manage anisometropic myopic amblyopia in children

OBJECTIVE

To compare the safety and efficacy of phakic intraocular lens (PIOL) versus intrastromal corneal ring segments (Intacs), for correcting high myopic anisometropia in amblyopic children.

DESIGN

Nonrandomized prospective multi-center study.

PARTICIPANTS

Thirty children, aged between 4 and 12 years, with unilateral high myopic anisometropic amblyopia were included in this study.

METHODS

Patients who were prospectively subdivided into group A, with mean preoperative manifest refraction spherical equivalent (MRSE) of -12.96 ± 4.17 D, underwent unilateral phakic posterior chamber intraocular lens implantation. Patients with mean preoperative MRSE of -8.60 ± 1.16 D in group B were treated by Intacs corneal rings. Pre- and postoperative visual acuity, ocular examination, stereoacuity, axial biometry measurements, cycloplegic refraction, and endothelial cell counts were performed in all patients.

RESULTS

Group A revealed prevention of amblyopia with improvement in spectacle-corrected distance visual acuity, where 4-6 lines were achieved in 77% of children, 2-3 lines in 4%, and just 0-1 lines restricted to 19% of children. Improvement in stereoacuity was noted in 93.33% of group A cases, whereas group B showed fewer cases of successfully improved vision, with 4-6 lines in 70% of children, 2-3 lines in 3%, and just 0-1 lines restricted to 27% of children. Improvement in stereoacuity was noted in 86.66% of cases. Two cases of cataract and 1 case of glaucoma with 1 case of uveitis were noted in the implantable contact lens (ICL) group.

CONCLUSIONS

Posterior chamber PIOLs or Intacs may provide a safe alternative in treating anisometropic myopic patients. Intacs implantation is safer with fewer complications than ICL. However, ICL implantation is advantageous over the corneal ring segment procedure owing to the wide range of errors to correct.

"Combined Occlusion and Atropine Therapy" Versus "Augmented Part-Time Patching" in Children with Refractory/Residual Amblyopia: A Pilot Study

Purpose:

To compare the efficacy of combined occlusion and atropine therapy (COAT) and augmented part-time patching for the treatment of unilateral refractory/residual amblyopia.

Methodology:

This retrospective study evaluated children between 4 and 11 years with refractory/residual amblyopia who were treated with either additional atropine (COAT group) or increased hours of patching (augmented group). Data were collected on improvement in best-corrected visual acuity (BCVA; logarithm of the minimum angle of resolution [logMAR] units) at each follow-up visit.

Results:

There were 19 children in the COAT group and 17 children in the augmented group. The baseline BCVA of the amblyopic eye was 0.79 ± 0.36 logMAR in the COAT group and 0.72 ± 0.26 logMAR in augmented group. Children were statistically significantly younger in the COAT group (6.4 ± 2.2 years) compared to the augmented group (8.6 ± 3.3 years, P = 0.02). The mean duration of follow-up was statistically significantly longer in the augmented group (20.2 COAT group; 13.9 months augmented group) (P = 0.03). Compliance was similar in both groups. LogMAR BCVA (adjusted for difference in age and baseline BCVA) was statistically significantly better in the COAT group (0.56 ± 0.04) compared to the augmented group (0.80 ± 0.04) at 3 months (P = 0.000); 6 months (COAT group, 0.50 ± 0.04 vs. augmented group, 0.74 ± 0.04; P = 0.04) and at 1 year (COAT group, 0.42 ± 0.04 vs. augmented group, 0.67 ± 0.04, P = 0.000). There was statistically significantly greater improvement in logMAR BCVA at 6 months in COAT group (0.26 ± 0.15) compared to the augmented group (0.02 ± 0.14), (P = 0.0002). Age, gender, pretreatment BCVA, duration of follow-up, or compliance to patching did not affect improvement in BCVA.

Conclusions:

COAT may result in greater improvement in BCVA than augmented part-time patching in children with unilateral residual/refractory amblyopia.

Risk factors for treatment failure and recurrence of anisometropic amblyopia

PURPOSE

The aim of this study was to identify factors associated with failed vision improvement and recurrence following occlusion therapy for anisometropic amblyopia in children aged 7-9 years.

METHODS

We retrospectively reviewed the medical records of 64 children aged 7-9 years who had been diagnosed as having anisometropic amblyopia and were treated with patching. Functional treatment failure was defined as final visual acuity in the amblyopic eye of worse than 20/32. Improvement of fewer than two logMAR lines was considered relative treatment failure. Recurrence was defined as the reduction of at least two logMAR levels of visual acuity after decreased or discontinued patching.

RESULTS

Functional and relative success rates were 51.6 and 62.5 %, respectively. The most important factor for functional treatment failure [adjusted odds ratio (OR) (95 % confidence interval, CI) 11.57 (1.4-95.74)] and the only risk factor for recurrence [adjusted OR (95 % CI) 3.04 (1.13-8.12)] were the same: high spherical equivalent (SE) of the amblyopic eye. A large interocular difference in the best-corrected visual acuity was found to be a risk factor for both functional and relative failure.

CONCLUSION

High SE of the amblyopic eye was the most influential risk factor for treatment failure and recurrence in compliant children aged 7-9 years.

Prevalence of amblyopia in primary school children in Qassim province, Kingdom of Saudi Arabia

PURPOSE

To determine the prevalence and causes of amblyopia in primary school children in Qassim province, Kingdom of Saudi Arabia (KSA).

MATERIALS AND METHODS

In this cross sectional study, 5176 children, aged 6 to 13 years (mean - 9.53 ± 1.88 years) were evaluated. There were 2573 (49.71%) males and 2603 (50.29%) females. Distance visual acuity (V/A) was tested monocularly using a logMAR chart with and without correction. Cycloplegic refraction was performed in children with reduced vision. To determine the etiology of amblyopia, children were enrolled if there was a difference in V/A of two or more lines between eyes or an absolute reduction in acuity <20/30 in either eye, that could not be corrected by refraction. P ≤ 0.05 was considered statistically significant.

RESULTS

There 202 out of 5176 (3.90%) with ambylopia. There are 98 (1.88%) amblyopic females. There was no statistical difference in gender for amblyopes (P > 0.05). The prevalence of amblyopia was statistically significant higher in the older age group (10-13 year) compared to younger age group (6 to 9 years) (P < 0.05). Unilateral amblyopia (3.24%) was more frequent than bilateral amblyopia (0.66%). The most frequent causes of amblyopia were refractive error (94.56%), of which anisometropic amblyopia was present in 77.72%, isoametropic amblyopia in 16.84% and strabismus in 5.44%.

CONCLUSION

The prevalence of amblyopia in Qassim province, KSA, is 3.9% which is similar or higher than other published studies on amblyopia. Anisometropic refractive errors are the most common underlying cause for this population. We recommend implementation of visual screening programs for children with appropriate clinical and social settings for early detection and proper management of amblyopia.

Impact of cylinder axis on the treatment for astigmatic amblyopia

PURPOSE

To compare the effects of oblique astigmatism on refractive amblyopia in children aged 3-7 years with those having orthogonal astigmatism.

DESIGN

A retrospective review of medical records.

METHODS

The medical records of patients attending Tri-Service General Hospital in Taiwan from January 2003 to December 2010 were reviewed and summarized. Seventy-two children with oblique astigmatism-related refractive amblyopia (Group 1) and 82 children with orthogonal astigmatism (Group 2) were chosen. Characteristics such as baseline visual acuity (VA), the time course of VA improvement, refractive error, and family history were assessed.

RESULTS

Group 1 showed a worse baseline mean VA (±SD) of 0.61 (0.13) vs 0.52 (0.16) logMAR (P = .01), a slower rate of amblyopia improvement, and higher prevalence of parental oblique astigmatism (29% vs 5.5%; P < .01) than did Group 2. The cylinder power of astigmatism (in D) causing amblyopia in Group 1 of 2.48 (0.82) was lower than that in Group 2: 2.93 (0.71) (P = .006). However, Group 1 achieved a noninferior resolution of amblyopia (mean final VA 0.18 vs 0.16 logMAR) after longer treatment of 6.45 (2.44) vs 5.86 (2.92) months (P = .039).

CONCLUSIONS

A smaller degree of initial oblique astigmatism caused amblyopia than did orthogonal astigmatism. Although the children with oblique astigmatism achieved equal resolution rates after treatment, this took longer. Therefore, we should pay more attention to children with mild oblique astigmatism, as they are more likely to develop oblique astigmatism-related amblyopia. Moreover, early diagnosis and prompt treatment might help visual improvement.

The relationship between higher-order aberrations and amblyopia treatment in hyperopic anisometropic amblyopia

PURPOSE

To investigate the relationship between higher-order aberrations (HOAs) and amblyopia treatment in children with hyperopic anisometropic amblyopia.

METHODS

The medical records of hyperopic amblyopia patients with both spherical anisometropia of 1.00 diopter (D) or more and astigmatic anisometropia of less than 1.00 D were reviewed retrospectively. Based on the results of the amblyopia treatment, patients were divided into two groups: treatment successes and failures. Using the degree of spherical anisometropia, subjects were categorized into mild, moderate, or severe groups. Ocular, corneal, and internal HOAs were measured using a KR-1W aberrometer at the initial visit, and at 3-month, 6-month, and 12-month follow-ups.

RESULTS

The results of the 45 (21 males and 24 females) hyperopic anisometropic amblyopia patients who completed the 12-month follow-up examinations were analyzed. The mean patient age at the initial visit was 70.3 months. In total, 28 patients (62.2%) had successful amblyopia treatments and 17 patients (37.8%) failed treatment after 12 months. Among the patient population, 24 (53.3%) had mild hyperopic anisometropia and 21 (46.7%) had moderate hyperopic anisometropia. When comparing the two groups (i.e., the success and failure groups), ocular spherical aberrations and internal spherical aberrations in the amblyopic eyes were significantly higher in the failure group at every follow-up point. There were no significant differences in any of the HOAs between mild and moderate cases of hyperopic anisometropia at any follow-up. When the amblyopic and fellow eyes were compared between the groups there were no significant differences in any of the HOAs.

CONCLUSIONS

HOAs, particularly ocular spherical aberrations and internal spherical aberrations, should be considered as reasons for failed amblyopia treatment.

Anisometropic amblyopia in a case of type 2 Waardenburg syndrome

This study presents a case of an 8-year-old boy with iris heterochromia and anisometropic amblyopia who was diagnosed with Waardenburg syndrome (WS) type 2. An ophthalmic examination revealed iris heterochromia and anisometropic amblyopia in our patient. In the systemic examination, a white forelock and vitiligo on the arms and body were observed and neurosensory hearing loss was revealed, for which the patient used hearing aids. Identification and typing of patients with WS is crucial to address neurosensory hearing loss, glaucoma and fundus changes. While it might be challenging to communicate with a patient with speech and hearing problems, visual acuity should be examined carefully and probable amblyopia should be identified. Anterior segment changes and signs of glaucoma should also be evaluated in detail.

The relationship between anisometropia and amblyopia

This review aims to disentangle cause and effect in the relationship between anisometropia and amblyopia. Specifically, we examine the literature for evidence to support different possible developmental sequences that could ultimately lead to the presentation of both conditions. The prevalence of anisometropia is around 20% for an inter-ocular difference of 0.5D or greater in spherical equivalent refraction, falling to 2-3%, for an inter-ocular difference of 3D or above. Anisometropia prevalence is relatively high in the weeks following birth, in the teenage years coinciding with the onset of myopia and, most notably, in older adults starting after the onset of presbyopia. It has about one-third the prevalence of bilateral refractive errors of the same magnitude. Importantly, the prevalence of anisometropia is higher in highly ametropic groups, suggesting that emmetropization failures underlying ametropia and anisometropia may be similar. Amblyopia is present in 1-3% of humans and around one-half to two-thirds of amblyopes have anisometropia either alone or in combination with strabismus. The frequent co-existence of amblyopia and anisometropia at a child's first clinical examination promotes the belief that the anisometropia has caused the amblyopia, as has been demonstrated in animal models of the condition. In reviewing the human and monkey literature however it is clear that there are additional paths beyond this classic hypothesis to the co-occurrence of anisometropia and amblyopia. For example, after the emergence of amblyopia secondary to either deprivation or strabismus, anisometropia often follows. In cases of anisometropia with no apparent deprivation or strabismus, questions remain about the failure of the emmetropization mechanism that routinely eliminates infantile anisometropia. Also, the chronology of amblyopia development is poorly documented in cases of 'pure' anisometropic amblyopia. Although indirect, the therapeutic impact of refractive correction on anisometropic amblyopia provides strong support for the hypothesis that the anisometropia caused the amblyopia. Direct evidence for the aetiology of anisometropic amblyopia will require longitudinal tracking of at-risk infants, which poses numerous methodological and ethical challenges. However, if we are to prevent this condition, we must understand the factors that cause it to develop.

Efficacy of split hours part-time patching versus continuous hours part-time patching for treatment of anisometropic amblyopia in children: a pilot study

AIM

To compare efficacy of 'split hours part-time patching' and 'continuous hours part-time patching' for the treatment of anisometropic amblyopia.

METHODS

We designed a prospective, interventional, non-randomised, comparative pilot study involving children between 4 and 11 years of age with anisometropic amblyopia who were treated with either continuous wear (Group A) or split hours part-time patching (Group B) as per parents wish, after appropriate discussion with the parents. Children were followed-up for the improvement in visual acuity and the compliance at each follow-up visit.

RESULTS

44 and 24 children were recruited in Group A and Group B, respectively (mean ± SD baseline BCVA of the amblyopic eye: 0.99 ± 0.32 and 0.95 ± 0.23 logMAR, respectively). BCVA (adjusted for baseline BCVA and age) at 3 months in Group A (0.59 ± 0.24) was comparable (p=0.08) with that in Group B (0.71 ± 0.24). This was same even at 6 months (0.51 ± 0.25 in Group A and 0.59 ± 0.25 in Group B, p=0.25). The improvement in BCVA at 3 months was also comparable (p=0.06) in Group A (0.39 ± 0.23) and Group B (0.26 ± 0.23). The improvement in BCVA at 6 months was also comparable (p=0.14) in Group A (0.47 ± 0.26) and Group B (0.37 ± 0.26).

CONCLUSIONS

Both patching regimens lead to significant and comparable improvement in BCVA in anisometropic amblyopia up to 6 months of follow-up.

Ocular disorders in children with spastic subtype of cerebral palsy

AIM

To document common ocular abnormalities in children with spastic subtype of cerebral palsy (CP) and to find out whether any correlation exists between their occurance and etiologic factors.

METHODS

Totally 194 patients with the diagnosis of spastic type CP were enrolled in this retrospective study. Detailed ophthalmic examinations were performed. Demographic data and neuroradiological findings were documented. Kruskal-Wallis, Mann Whitney U, Pearson Chi-square tests and Student's t tests were used in the statistical analysis.

RESULTS

The mean age was 64.7±44.2 months on the first ophthalmic examination. Prevalences of diplegia (47.4%) and tetraplegia (36.1%) were found to be higher than the frequency of hemiplegia (16.5%) in our study population. Etiologic factor was asphyxia in 60.8% of the patients. Abnormal ocular findings were present in 78.9% of the patients. Statistically significant poor vision was detected in tetraplegia group among all the spastic ubtypes of CP (P=0.000). Anisometropia and significant refractive error were found in 14.4% and 70.1% of the patients, respectively. Thirty-six children (18.6%) had nystagmus and 107 children (55.2%) had strabismus. Lower gestational age and birth weight were statistically higher in patients with esotropia than exotropia (P=0.009 and P=0.024, respectively). Abnormal morphology of the optic disc was present in 152 eyes (39.2%). Severe periventricular leukomalacia (PVL) was found in 48 patients and statistically significant poor vision was detected in the presence of PVL (P=0.000).

CONCLUSION

Spastic diplegic or tetraplegic CP patients with positive neuroradiological symptoms, younger gestational age and lower birth weight ought to have detailed ophthalmic examinations as early as possible to provide best visual rehabilitation.

Posterior chamber toric phakic IOL implantation for the management of pediatric anisometropic amblyopia

PURPOSE

To report the outcomes of toric posterior chamber phakic intraocular lens (PIOL) implantation in children for the treatment of amblyopia due to anisometropia with astigmatism.

METHODS

Six eyes of 6 amblyopic patients aged 5 to 15 years underwent toric PIOL (Visian Toric ICL; STAAR Surgical Company, Monrovia, CA) implantation for refractory anisometropic amblyopia. Preoperative and postoperative clinical evaluation included slit-lamp microscopy, visual acuity, anterior/posterior segment examination, and cycloplegic refraction.

RESULTS

After a mean follow-up of 23 months (range: 15 to 34 months), mean spherical equivalent cycloplegic refraction improved from -10.21 ± 4.62 diopters (D) (range -7.5 to -19.5 D) preoperatively to -0.42 ± 0.39 D (range: -0.625 to +0.125 D) postoperatively. Corrected distance visual acuity ranged from 20/40 to 20/200 preoperatively and 20/20 to 20/60 postoperatively. Five of the 6 eyes gained more than 3 lines of corrected distance visual acuity with a maximum gain of 8 lines in one eye. One eye showed an improvement of more than 2 lines (change in preoperative visual acuity of 20/100 to 20/60 postoperatively). No patients lost any lines of visual acuity. All eyes remained quiet. All PIOLs remained well centered throughout the follow-up period.

CONCLUSION

Toric PIOL implantation may be a viable therapeutic modality in children with clinically significant anisometropic ametropia and astigmatism with secondary amblyopia who have been refractory to medical treatment including spectacles or contact lenses. Longer follow-up visits with larger sample populations will evaluate more effectively the long-term efficacy and late-onset of complications.

Childhood vision screening in Canada: public health evidence and practice

OBJECTIVES

Best practice guidelines recommend vision testing in children 3 to 5 years of age for the prevention of amblyopia; however, universal vision screening is controversial. In Canada, amblyopia screening can be the responsibility of physicians, optometrists, and/or Public Health. We review the evidence underlying preschool vision screening for amblyopia using an Evidence-based Public Health (EBPH) approach, and consider implications for the Public Health provision of universal screening programs for amblyopia in Canadian jurisdictions in light of present practices.

METHODS

We searched the literature to address each major screening criterion (disease, test, treatment, program requirements) necessary to support preschool vision screening for amblyopia. We also reappraised papers cited in two systematic reviews related to the impact of vision screening. The Chief Medical Officer of Health of each province/territory was sent a short survey asking whether there currently was a Public Health preschool vision screening program in place and if so, for specifics about the program.

RESULTS

An EBPH approach to the literature with respect to the criteria for screening and available intervention studies support amblyopia screening by Public Health. There is a public health divide in amblyopia screening practice in Canada; while some provinces maintain organized programs, others have chosen to delegate the task to other professionals, without a concurrent surveillance function to monitor disparities in uptake.

CONCLUSIONS

Amblyopia deserves attention from Public Health. Efforts should be made to maintain existing programs, and provinces without organized screening programs should reconsider their role in the prevention of inequities with regard to preventable blindness in Canadian children.

Compliance of amblyopic patients with occlusion therapy: A pilot study

BACKGROUND

Increasing evidence shows that good compliance with occlusion therapy is paramount for successful amblyopia therapy.

PURPOSE

To study the degree of compliance and explore factors affecting compliance in patients undergoing occlusion therapy for amblyopia in our practice.

DESIGN

Nonrandomized clinical intervention study.

MATERIALS AND METHODS

A total of 31 families with a child (aged 2-12 years), undergoing unilateral amblyopia treatment at the pediatric ophthalmology clinic of Sultan Qaboos University Hospital, Oman, were recruited for this one month study. Parents were interviewed and completed a closed-ended questionnaire. Clinical data including, visual acuity, refraction, diagnosis and treatment, for each patient was collected from the hospital chart and was entered in a data collection sheet. Compliance with occlusion therapy was assessed by self-report accounts of parents and was graded into good, partial, or poor. Association between various factors and degree of compliance was studied using logistic regression modeling.

RESULTS

Only 14 (45%) patients showed good compliance to occlusion therapy. 17 (55%) patients were noncompliant. Improvement in visual acuity strongly correlated with compliance to patching (P = 0.008). Other variables that were studied included, age at onset of therapy; gender; degree of amblyopia; type of amblyopia; use of glasses; and compliance with glasses. These did not emerge as significant predictors of compliance. All but one family with poor compliance stated that the main challenge in following the recommendation to patch for requisite hours was in getting their child to cooperate. Only in one instance, the family cited nonavailability of patches as the main hindrance to compliance. 10/31 (32%) families expressed a desire for more information and 18/31 (58%) parents did not understand that amblyopia meant decreased vision.

CONCLUSION

Poor compliance is a barrier to successful amblyopia therapy in our practice. Improvement in visual acuity is associated with better compliance with patching. Parents find it difficult to comprehend and retain verbal explanations of various components regarding occlusion therapy for amblyopia. Future study with a larger sample of patients is recommended to investigate the factors affecting compliance with amblyopia therapy and determine predictors for poor compliance.

Factors influencing the prevalence of amblyopia in children with anisometropia

Purpose

To evaluate factors that can influence the prevalence of amblyopia in children with anisometropia.

Methods

We retrospectively reviewed the records of 63 children 2 to 13 years of age who had anisometropic amblyopia with a difference in the refractive errors between the eyes of at least two diopters (D). The type of anisometropia (myopia, hyperopia, and astigmatism), degree of anisometropia (<2-3 D, <3-4 D, or >4 D), best corrected visual acuity (BCVA) of the amblyopic eye at the time of initial examination, BCVA differences between sound and amblyopic eyes, whether or not occlusion therapy was performed, compliance with occlusion therapy, and the patient's age when eyeglasses were first worn were investigated.

Results

There was an increase in the risk of amblyopia with increased magnitude of anisometropia (p=0.021). The prevalence of amblyopia was higher in the BCVA <20/40 group and in patients with BCVA differences >4 lines between sound and amblyopic eyes (p=0.008 and p=0.045, respectively). There was no statistical relationship between the prevalence of amblyopia and the type of anisometropia or the age when eyeglasses were first worn. Poor compliance with occlusion therapy was less likely to achieve successful outcome (p=0.015).

Conclusions

Eyes with poor initial visual acuities of <20/40, a high magnitude of anisometropia, and a >4 line difference in the BCVA between sound and amblyopic eyes at the initial visit may require active treatment.

Corneal Higher-Order Aberrations in Amblyopia

Purpose

To investigate the amount, type, and role of corneal higher order aberrations in both isotropic and anisometropic amblyopic adult patients.

Methods

A total of 125 eyes of 78 patients with age ranging from 18 to 67 years (30 patients with unilateral amblyopia, 17 with bilateral amblyopia, and 31 normal eyes considered as the control group) were included. All eyes received a comprehensive ophthalmologic examination that included corneal topographic and aberrometric analysis with the CSO system. The aberrometric study was performed for a 6-mm pupil using different root mean square (RMS) parameters. Additionally, the ocular residual astigmatism (ORA) was also calculated and analyzed. A comparative analysis of the refractive and aberrometric data between groups was performed.

Results

In the unilateral amblyopia group, statistically significant differences between the amblyopic and non-amblyopic eye were found in cylinder (p=0.003), best-corrected visual acuity (BCVA) (p<0.001), total RMS (p=0.015), and astigmatic RMS (p=0.019). Statistically significant differences between the bilateral amblyopia and control groups were observed in sphere (p=0.025), cylinder (p=0.005), and BCVA (p <0.001). When comparing isometropic and anisometropic bilateral amblyopic eyes, significant differences in total (p=0.025) and astigmatic RMS (p=0.013) were detected. Higher but nonsignificant amounts of primary coma were found in isometropic eyes (0.25 μm anisometropic vs 0.43 μm isometropic, p=0.09). Regarding the ORA, no significant differences between groups were found (p≥0.224).

Conclusions

In unilateral and bilateral amblyopia, lower order aberrations are the main refractive factors leading to amblyopia. Higher order aberrations could have a bilateral amblyogenic effect in those cases where isometropia is present.

Current thoughts in pediatric refractive surgery

The goal of this article is to review current literature regarding the emerging field of pediatric refractive surgery. This encompasses current thought in adult refractive surgery, published literature in pediatric refractive surgery, and future possibilities for refractive technology in the pediatric population. This study includes a comprehensive review of literature in the general refractive surgery, cornea, and pediatric literature.

The age-dependent effect of anisometropia magnitude on anisometropic amblyopia severity

INTRODUCTION

Anisometropia is an important cause of amblyopia. The relationship between anisometropia depth and amblyopia magnitude is not well characterized, as previous studies have been limited to patients identified because of their amblyopia. We analyzed results from anisometropic patients identified with photoscreening to eliminate this selection bias.

METHODS

We performed a retrospective observational study of preschool children with anisometropia >1.0 D identified during a statewide photoscreening program. Nine hundred seventy-four children with anisometropia were detected over a 9-year period. Visual acuity, cycloplegic refraction data, and patient age from a formal follow-up examination were analyzed. Effect of anisometropia magnitude on amblyopia was measured by ordinal logistic regression, taking age into account.

RESULTS

Six hundred forty (65.7%) children had amblyopia > or =2 lines. Three hundred sixty-four (37.4%) had > or =4 lines amblyopia. There was a statistically significant increase in risk of amblyopia with increasing magnitude of anisometropia. Calculated odds ratios for amblyopia with maximal meridional anisometropia of > or =2 to <4 D compared with >1 to <2 D was 2.13 (95% CI [1.63, 2.78], p < 1 x 10(-7)), and 2.34 (95% CI [1.67, 3.28], p < 1 x 10(-6)) when comparing > or =4 D to > or =2 to <4 D. Odds ratios for spherical equivalent anisometropia were also highly statistically significant.

CONCLUSIONS

Children with higher magnitudes of anisometropia had higher prevalence and greater depth of amblyopia. Older children had an increased risk of amblyopia compared with younger children for moderate levels of anisometropia. Low magnitude anisometropia in young children may not predispose to amblyopia; these findings have implications for vision screening criteria at various ages.

Eye involvement in children with primary focal segmental glomerulosclerosis

Distinct eye abnormalities have been described in children with nephrotic syndrome, particularly in diffuse mesangial sclerosis (i.e. Pierson syndrome). The aim of the study was to investigate whether there were any associated ocular anomalies in children with steroid-resistant nephrotic syndrome (SRNS), all of whom had revealed primary focal segmental glomerulosclerosis in biopsy. Thirty-three SRNS patients (16 male, 17 female) with a median age of 10.5 years (range 3-25 years) were enrolled in the study. Twenty steroid-sensitive nephrotic syndrome (SSNS) patients (ten male, ten female) with a median age of 8 years (range 3-15 years) served as controls. All SRNS patients were examined by mutational analysis for mutations in the NPHS2, WT1, and LAMB2 genes. Nine out of 33 SRNS patients (27.2%) showed various eye abnormalities. However, no abnormal ocular findings were detected in any of the SSNS patients. Abnormal eye findings detected in SRNS patients were anisometropic amblyopia (n = 4), Mittendorf's dots (n = 4), myopic astigmatism (n = 3) and exotropia (n = 1). Macular pigment changes (n = 1), posterior subcapsular opacities (n = 1) and cataract (n = 1) were considered as steroid-induced side effects. In four patients, more than one eye abnormality was found. Mutational analysis for the NPHS2, WT1 and LAMB2 genes revealed disease-causing mutations in 24.2% of patients. Homozygous NPHS2 mutations were detected in five patients (15.1%), all of whom had parental consanguinity. In three patients (9%) from non-consanguineous parents, heterozygous de novo WT1 mutations were detected as disease-causing mutations. No LAMB2 mutation was detected in any patient. While four out of five (80%) patients with homozygous NPHS2 mutations showed at least one abnormal ocular finding (i.e. Mittendorf's dot or anisometric amblyopia), none of the patients with a WT1 mutation had ocular involvement. In conclusion, ocular involvement may accompany SRNS caused by primary focal segmental glomerulosclerosis (FSGS). Ophthalmologic evaluation at the time of diagnosis might be beneficial to characterize further the spectrum of this possible association.

Unilateral lens extraction for high anisometropic myopia in children and adolescents

INTRODUCTION

A subpopulation of children with anisometropic myopia, amblyopia, and neurobehavioral disorders is noncompliant with spectacle wear and ill-suited to correction using contact lenses. We report the results of refractive surgery in a series of these children treated using lensectomy alone (clear lens extraction) or lensectomy with simultaneous implantation of an intraocular lens (refractive lens exchange).

METHODS

Clinical course and outcome data were collated retrospectively in a group of 7 children and adolescents (mean age, 9.1 years; range, 4-20 years) with neurobehavioral disorders and noncompliance with spectacle wear for anisometropic myopia. Myopia in the 7 eyes ranged -11.9 to -24.5 D (mean, -16.7 D). Goal refraction was 0 to + 4 D. Correction was achieved by lensectomy in 5 eyes and lensectomy with intraocular lens implantation in 2 eyes. Primary posterior capsulectomy/subtotal vitrectomy was performed during the primary procedure in 5 eyes (71%). Mean follow-up was 3.8 years (range, 0.5-5.4 years).

RESULTS

Myopia correction averaged 17.3 D. A total of 86% (6 eyes) were corrected within +/- 3 D of the goal refraction and the remaining 14% to within +/- 4 D. Uncorrected visual acuity improved postoperatively in all 7 eyes, albeit modestly (average gain 0.14 Snellen fraction; gain from a mean 20/2550 to a mean 20/130). Myopic regression averaged approximately 0.43 D/year. Capsular opacification necessitated YAG-laser membranectomy in the 2 eyes that had preservation of the posterior capsule at the primary procedure. Retinal detachment has not occurred in any of the eyes during the follow-up period.

CONCLUSIONS

Refractive myopic lensectomy reduced high anisometropia and improved functional vision in children who have high myopia beyond the range of excimer laser correction and who will not wear glasses. Further study is indicated to determine the long-term safety of this procedure in similar pediatric populations.

Relationship between anisometropia, patient age, and the development of amblyopia

PURPOSE

Previous studies evaluating the effect of anisometropia on amblyopia development have been biased because subject selection occurred as a result of decreased acuity. Photoscreening identifies anisometropic children in a manner that is not biased by acuity, and allows an opportunity to evaluate how patient age influences the prevalence and depth of amblyopia.

DESIGN

Retrospective observational study of preschool children with anisometropia.

METHODS

A statewide preschool photoscreening program screened 119,311 children and identified 792 with anisometropia >1.0 diopters. We correlated age with visual acuity and amblyopia depth. Results were compared with 562 strabismic children similarly identified.

RESULTS

Only 14% (six of 44) of anisometropic children aged 1 year or younger had amblyopia. Amblyopia was detected in 40% (32 of 80) of 2-year-olds, 65% (119 of 182) of 3-year-olds, and 76% of 5-year-olds. Amblyopia depth also increased with age. Moderate amblyopia prevalence was 2% (ages 0 to 1), 17% (age 2), and rose steadily to 45% (ages 6 to 7). Severe amblyopia was rare for children aged 0 to 3, 9% at age 4, and 14% at age 5. Children with strabismus had a relatively stable prevalence (30% ages 0 to 2; 42% ages 3 to 4; and 44% ages 5 to 7) and depth of amblyopia.

CONCLUSIONS

Younger children with anisometropia have a lower prevalence and depth of amblyopia than older children. By age 3, when most children undergo traditional screening, amblyopia has usually already developed. New vision screening technologies that allow early detection of anisometropia provide ophthalmologists an opportunity to intervene early, perhaps retarding or even preventing the development of amblyopia.

Why is compliance with occlusion therapy for amblyopia so hard? A qualitative study

OBJECTIVE

To explore parents' perceptions and experiences of occlusion (patching) therapy for treatment of amblyopia in children.

METHODS

Qualitative study involving semistructured interviews with 25 families of a child with amblyopia being treated at a specialist clinic. Interviews were tape recorded and transcribed verbatim. Data analysis was based on the constant comparative method, assisted by qualitative analysis software.

RESULTS

Parents of children prescribed patching treatment found themselves obliged to manage the treatment. This involved dilemmas and tensions, with many parents describing children's distress, particularly in the early stages of patching treatment. Parents were highly sensitive to the credibility of the treatment, but were sometimes confused by information given in the clinic or did not see clinic staff as authoritative. There was evidence that parents were likely to abandon or modify treatment if no improvement could be detected or if the child continued to suffer socially or educationally. Parents described a range of strategies for facilitating patching, including explanation; normalisation; rewards; customising the patch; establishing a routine; and enlisting the help of others. Whatever their practices in relation to patching, parents were keen to defend their behaviour as that of a "good parent".

CONCLUSIONS

Interventions that aim to improve compliance should take account of the difficulties and tensions experienced by parents, rather than simply treating non-compliance as resulting from information deficits. Practical support that builds on strategies described by parents is likely to be of benefit.

Amblyopia characterization, treatment, and prophylaxis

Amblyopia has a 1.6-3.6% prevalence, higher in the medically underserved. It is more complex than simply visual acuity loss and the better eye has sub-clinical deficits. Functional limitations appear more extensive and loss of vision in the better eye of amblyopes more prevalent than previously thought. Amblyopia screening and treatment are efficacious, but cost-effectiveness concerns remain. Refractive correction alone may successfully treat anisometropic amblyopia and it, minimal occlusion, and/or catecholamine treatment can provide initial vision improvement that may improve compliance with subsequent long-duration treatment. Atropine penalization appears as effective as occlusion for moderate amblyopia, with limited-day penalization as effective as full-time. Cytidin-5'-diphosphocholine may hold promise as a medical treatment. Interpretation of much of the amblyopia literature is made difficult by: inaccurate visual acuity measurement at initial visit, lack of adequate refractive correction prior to and during treatment, and lack of long-term follow-up results. Successful treatment can be achieved in at most 63-83% of patients. Treatment outcome is a function of initial visual acuity and type of amblyopia, and a reciprocal product of treatment efficacy, duration, and compliance. Age at treatment onset is not predictive of outcome in many studies but detection under versus over 2-3 years of age may be. Multiple screenings prior to that age, and prompt treatment, reduce prevalence. Would a single early cycloplegic photoscreening be as, or more, successful at detection or prediction than the multiple screenings, and more cost-effective? Penalization and occlusion have minimal incidence of reverse amblyopia and/or side-effects, no significant influence on emmetropization, and no consistent effect on sign or size of post-treatment changes in strabismic deviation. There may be a physiologic basis for better age-indifferent outcome than tapped by current treatment methodologies. Infant refractive correction substantially reduces accommodative esotropia and amblyopia incidence without interference with emmetropization. Compensatory prism, alone or post-operatively, and/or minus lens treatment, and/or wide-field fusional amplitude training, may reduce risk of early onset esotropia. Multivariate screening using continuous-scale measurements may be more effective than traditional single-test dichotomous pass/fail measures. Pigmentation may be one parameter because Caucasians are at higher risk for esotropia than non-whites.

Successful management of pediatric high anisometropia using traditional treatment methods: a case series

PURPOSE

To report visual results in pediatric patients with high anisometropia following aggressive amblyopia treatment using traditional methods.

METHODS

Charts of one physician, JM, were reviewed at a major university medical center for all patients with anisometropia of eight diopters or greater. Patients ranged from children with severe unilateral high myopia due to retinopathy of prematurity to one infant with severe microphthalmos, acoria, and congenital cataract. Four patients were identified. Final Snellen acuities were reported from the patient's last clinic examination. Average follow-up period was four years.

RESULTS

Final visual acuities of involved eyes ranged from line Snellen 20/60 to 20/20. One patient with severe microphthalmos, congenital acoria, congenital cataract, and anisometropia of 40 diopters achieved a final Snellen visual acuity of 20/40 OS. No patients developed visual loss in the normal eye due to patching. No patients were lost to follow-up.

CONCLUSION

Based on our observations, excellent visual outcomes may be achieved in pediatric patients with high anisometropia by aggressive use of conventional occlusion and refractive methods.