Wendy Marsh-Tootle

Treatment of severe amblyopia with weekend atropine: Results from 2 randomized clinical trials

PURPOSE To determine the effectiveness of weekend atropine for severe amblyopia from strabismus, anisometropia, or both combined among children 3 to 12 years of age. METHODS We enrolled children into 2 prospective, randomized multicenter clinical trials of amblyopia therapy. Herein we report the results for severe amblyopia, 20/125 to 20/400. In Trial 1, 60 children 3 to 6 years of age (mean, 4.4 years) were randomized to weekend atropine plus a plano lens or weekend atropine plus full spectacle correction for the sound eye. In Trial 2, 40 children 7 to 12 years of age (mean, 9.3 years) were randomized to weekend atropine or 2 hours of daily patching. The visual acuity outcome was assessed at 18 weeks in Trial 1 and 17 weeks in Trial 2. RESULTS In Trial 1, visual acuity improved by an average of 4.5 lines in the atropine plus correction group (95% CI, 3.2-5.8 lines) and 5.1 lines in the atropine plus plano lens group (95% CI, 3.7-6.4 lines). In Trial 2, visual acuity improved by an average of 1.5 lines in the atropine group (95% CI, 0.5-2.5 lines) and 1.8 lines in the patching group (95% CI, 1.1-2.6 lines). CONCLUSIONS Weekend atropine can improve visual acuity in children 3 to 12 years of age with severe amblyopia. Improvement may be greater in younger children.

The Correction of Myopia Evaluation Trial (COMET): design and general baseline characteristics.

The Correction of Myopia Evaluation Trial (COMET) is a multicenter, randomized, double-masked, controlled clinical trial evaluating whether there is a difference in the progression of myopia between children wearing progressive addition lenses (PALs) versus conventional single vision lenses (SVLs), as measured by cycloplegic autorefraction. Axial length, measured by A-scan ultrasonography, is an additional outcome measure. To meet the recruitment goal of 450 participants, eligible children ages 6-11 years (inclusive) with myopia in both eyes (spherical equivalent between -1.25 diopters (D) and -4.50 D, astigmatism < or = 1.50 D, and anisometropia < 1.00 D) were recruited at four clinical centers between September 1997 and September 1998. Children who participated were assigned to receive PALs (Varilux Comfort with a +2.00 D addition) or SVLs. Measures include standardized cycloplegic autorefraction (Nidek ARK700A autorefractor), axial length (Sonomed A2500 ultrasound), subjective refraction (Marco TRS system), visual acuity (modified Early Treatment Diabetic Retinopathy Study protocol), accommodation (Canon R-1), and phoria (cover test and Maddox rod). Outcome measures are collected annually; adherence is assessed and prescriptions updated semiannually. Participants are being followed for at least 3 years. COMET enrolled 469 children. Their mean age is 9.3 years (range 6-11 years); 52% are female. COMET children are ethnically diverse, according to a self-report with 46% White, 26% African American, 14% Hispanic, and 8% Asian. Best-corrected visual acuity is better than 20/32 in both eyes. Baseline mean (+/-SD) cycloplegic refractive correction is -2.38 D (+/-0.81) in the right eye and -2.40 D (+/-0.82) in the left eye; mean (+/-SD) axial length is 24.1 mm (+/-0.7) in both eyes. Follow-up of these children will provide a first step in answering the important question of whether there are effective means to slow myopia progression. Study results should be applicable to a large proportion of children with myopia. The study will also provide useful information on myopia progression in children wearing conventional single vision lenses.

Compliance With Vision-Screening Guidelines Among a National Sample of Pediatricians

OBJECTIVE The American Academy of Pediatrics (AAP) recommends vision screening from birth through adolescence, with visual acuity testing and binocular screening to begin at age 3 years. The 1996 AAP guidelines advised referral for visual acuity worse than 20/40 for children aged 3 to 5 years and worse than 20/30 for children aged 6 years and older. Our objective was to describe vision-screening and referral practices in a national sample of primary care pediatricians. METHODS We mailed a survey to a random sample of US pediatricians. Initial nonresponders were mailed up to 3 additional surveys. All mailings occurred between May and October 1998. Analyses focused on primary care pediatricians and consisted of descriptive statistics and regression analyses. The main outcome measure was compliance with 1996 AAP recommendations for vision screening. RESULTS Of the 1491 surveys mailed, 888 (60%) were returned, including 576 (65%) from primary care pediatricians. Vision-screening methods included visual acuity testing (92%), cover test (64%), red reflex test (95%), fundoscopic examinations (65%), and stereopsis testing (32%). Respondents routinely performed visual acuity testing at 3 years (37%), 4 years (79%), 5 years (91%), 6 years (80%), 7-12 years (82%), and 13-18 years (80%). Visual acuity thresholds for referring 3- and 4-year-olds were 20/40 (47%, 51%), 20/50 (36%, 32%), or worse than 20/50 (14%, 12%). The majority of pediatricians referred children aged 5 years and older at 20/40, although thresholds worse than 20/40 were reported commonly (18%-33%). Logistic regressions were done to identify factors associated with higher likelihood of performing specific screening tests. Although no factor was consistently associated with use of all screening tests, size of the practice was significant in several regression models. CONCLUSIONS Many pediatricians do not follow AAP guidelines for vision screening and referral, especially in younger children. Two thirds of pediatricians do not begin visual acuity testing at age 3 years as recommended, and about one fifth do not test until age 5 years. In addition, one fourth do not perform cover tests or stereopsis testing at any age.

Clinical course of accommodative esotropia

Purpose. To report the clinical course of patients having accommodative esotropia and to determine whether the strabismus resolves during the adolescent years. Methods. Patients diagnosed with accommodative esotropia from 1983 to 1991 were recalled to the clinic for re-examination. For all patients, the clinical records indicated that the esotropia had begun in early childhood and was controllable at some time during the follow-up period with plus power single vision glasses and/or bifocals. Re-examination included assessment of patient history, visual acuity, ocular alignment, versions, sensory fusion, and refractive error. The ocular alignment status with and without any current plus single vision and/or bifocal correction, and the refractive error at recall, were compared to the same findings taken at the patients initial clinic visit. These findings were compared to determine whether the accommodative esotropia had resolved, improved, remained the same, or increased in amount. Results. Thirty-nine patients participated in the study. At the time of recall their average age and follow-up period were 16.8 and 9.5 years, respectively. Before treatment, the mean eso deviation was 14.5δ at distance and 21.6δat near. At recall, 15 patients used single vision glasses, 9 used glasses with bifocals, 11 used contact lenses, and 4 patients used no optical correction. Five patients (12.8%) had best corrected acuity in one eye of 20/30 or poorer. Twenty patients (57.1%) were not strabismic with their current refractive correction, whereas 15 patients (42.8%) continued to be esotropic (intermittent or constant) at distance and/or near. When assessing ocular alignment without the current plus power correction, 26 patients (82%) were esotropic and 4 patients (15.6%) were heterophoric. The mean deviation without the optical correction was 18.6δ at distance and 19δ at near. Of the 4 patients presenting without an optical correction, 3 were esotropic at distance and/or near and 1 patient was heterophoric. Six patients (15.3%) also had inferior oblique overaction, 2 which occurred with superior oblique palsy. Thirty-three patients (86.8%) fused the Worth dot test at distance and/or near, and 35 patients (89.7%) had stereopsis (mean, 84 sec arc). The mean spherical equivalent refractive error changed for the group from 2.77 D hyperopia at the initial evaluation to 1.95 D hyperopia at recall (mean refractive shift=-0.08 D/year). Conclusions. Accommodative esotropia persists for most patients into adolescence and early adulthood. These patients need to be carefully monitored during this period because most do not outgrow their hyperopia and some can again become esotropic. (Optom Vis Sci 1998;75:97-102)

Factors Associated with High Myopia After 7 Years of Follow-up in the Correction of Myopia Evaluation Trial (COMET) Cohort

Purpose: To evaluate factors associated with the development of high myopia (worse than −6.00 D) over 7 years of follow-up in the COMET cohort. Methods: COMET enrolled 469 ethnically diverse children (6–11 years) with myopia between −1.25 and −4.50 D. They were randomized to either progressive addition lenses (PALs) or single vision lenses (SVLs), and followed for 5 years in their original lens assignment and 2 additional years wearing either spectacles (PALs or SVLs) or contact lenses. Refractive error was measured annually by cycloplegic autorefraction and axial length by A-Scan ultrasonography. Myopia for each child was defined as the mean spherical equivalent refractive error (SER) of the 2 eyes. Analyses were based on 7 years of follow-up. Time to high myopia was analyzed by Cox proportional hazard models and linear regression. Parental refraction data were available from 240 COMET subjects. Results: Younger (6–7 years) versus older (11 years) age at baseline was a significant risk factor (adjusted hazard ratio (HR) = 6.6, 95% CI = 3.4, 12.7) for having high myopia within 7 years. More (SER from −2.26 to −4.50 D) vs. less (SER from −1.25 to −2.25 D) baseline myopia was also a significant risk factor for high myopia at 7 years (adjusted HR = 7.4, 95% CI = 4.4, 12.4). Gender, ethnicity, and treatment assignment were not associated with the risk of high myopia within 7 years. Increased number of myopic parents was associated with a significant risk of high myopia in the children (p = 0.008). Conclusions: Children who developed high myopia during 7 years of follow-up were younger and had more myopia at baseline. They also were more likely to have two myopic parents. These children may be at greater risk for sight-threatening conditions later in life.

Project Universal Preschool Vision Screening: A Demonstration Project

OBJECTIVES. Visual disorders among preschool-aged children are common, yet screening is infrequent. The purpose of this project was to implement the vision screening recommendations proposed by the Maternal and Child Health Bureau and National Eye Institute Vision Screening in the Preschool Child Task Force: monocular visual acuity and stereopsis testing. METHODS. Four sites fully participated in the implementation of the task force recommendations with 3- and 4-year-old children. Two of the sites worked with primary care practices (testing performed by staff); 2 worked with community-based programs (testing performed by lay volunteers). Each site tracked number of children screened by age, as well as proportion testable, referred, and with documented follow-up evaluation. RESULTS. Variations in implementation of the recommendations were observed. Successful screening among 3-year-olds ranged from 70% to 93%; referral rates were 1% to 41%, and follow-up rates were 29% to 100%. Successful screening among 4-year-olds ranged from 88% to 98%; referral rates were 2% to 40%, and follow-up rates were 41% to 100%. The proportion of 3-year-olds who were treated was significantly different between the community-based sites (n = 20) and the primary care sites (n = 2). Similarly, the proportion of 4-year-olds who were treated was significantly different between the community-based sites (n = 36) and the primary care sites (n = 11). CONCLUSIONS. The variability across pilot sites in numbers successfully screened and numbers referred suggests that all aspects of preschool vision screening need thorough review before the goal of universal preschool vision screening can be realized.

Quantitative Pediatric Vision Screening in Primary Care Settings in Alabama

Purpose. Alabama Medicaid reimburses “objective” vision screening (VS), i.e., by acuity or similar quantitative method, and well child checks (WCCs) separately. We analyzed the frequency of each service obtained. Methods. Claims for WCC and VS provided between October 1, 2002 and September 30, 2003 for children aged 3 to 18 years, and summary data for all enrolled children, were obtained from Alabama Medicaid. We used univariate analysis followed by logistic regression to explore the potential influence of factors (patient age, provider type, and provider’s volume of WCCs) on the receipt of VS at pre-school ages. Results. Children receiving WCCs were 55% black, 40% white, and 5% other. Percentages of children with WCC claims were highest at 4 years (57%) and thereafter declined to 30% at 6 to 14 years and to <10% at 18 years. Nearly all VS (>98% at each age) occurred the same day as the WCC. Pediatricians provided 68% of all WCCs. Multivariate analysis, after adjusting for nesting of pre-school patients within provider, showed the odds ratios (ORs) of VS were increased by patient age (5 years vs. 3 years, OR = 3.57, p < 0.0001), nonphysician provider type (nonphysician vs. pediatrician, OR = 1.80, p = 0.0004) and high WCC volume (at or above vs. below the median number (n = 8) of WCC per provider per year (OR = 7.11, p < 0.0001)). Because VS rates were high when attendance to WCC visits was low, few enrolled children received VS at any age (6% at the age of 3, 13% at the age of 4, and a maximum of 20% at the age of 5). Conclusions. National efforts to reduce preventable vision loss from amblyopia are hampered because children are not available for screening and because providers miss many opportunities to screen vision at pre-school age. Efforts to improve VS should target pediatrician-led practices, because these serve greater numbers of children.

Accommodative lag by autorefraction and two dynamic retinoscopy methods.

Purpose. To evaluate two clinical procedures, Monocular Estimate Method (MEM) and Nott retinoscopy, for detecting accommodative lags 1.00 diopter (D) or greater in children as identified by an open-field autorefractor. Methods. One hundred sixty-eight children 8 to <12 years old with low myopia, normal visual acuity, and no strabismus participated as part of an ancillary study within the screening process for a randomized trial. Accommodative response to a 3.00 D demand was first assessed by MEM and Nott retinoscopy, viewing binocularly with spherocylindrical refractive error corrected, with testing order randomized and each performed by a different masked examiner. The response was then determined viewing monocularly with spherical equivalent refractive error corrected, using an open-field autorefractor, which was the gold standard used for eligibility for the clinical trial. Sensitivity and specificity for accommodative lags of 1.00 D or more were calculated for each retinoscopy method compared to the autorefractor. Results. One hundred sixteen (69%) of the 168 children had accommodative lag of 1.00 D or more by autorefraction. MEM identified 66 children identified by autorefraction for a sensitivity of 57% (95% CI = 47 to 66%) and a specificity of 63% (95% CI = 49 to 76%). Nott retinoscopy identified 35 children for a sensitivity of 30% (95% CI = 22 to 39%) and a specificity of 81% (95% CI = 67 to 90%). Analysis of receiver operating characteristic curves constructed for MEM and for Nott retinoscopy failed to reveal alternate cut points that would improve the combination of sensitivity and specificity for identifying accommodative lag ≥1.00 D as defined by autorefraction. Conclusions. Neither MEM nor Nott retinoscopy provided adequate sensitivity and specificity to identify myopic children with accommodative lag ≥1.00 D as determined by autorefraction. A variety of methodological differences between the techniques may contribute to the modest to poor agreement.

Changes in Refractive Error for Exotropes Treated with Overminus Lenses

The refractive changes of pediatric patients who were prescribed overminus lenses for exotropia were evaluated. Overminus lenses means additional minus power over the lenses required to correct the refractive error at distance. Forty exotropic patients, ages 1 to 15 years, were prescribed overminus lenses (-0.50 D to -3.75 D) for a period of 9 to 86 months. A small but significant correlation was found between the initial refractive error and the mean annual change toward myopia. Other factors such as age when treatment was given, duration of therapy, amount of overminus, and the amount of the exodeviation had little effect on the rate of myopic change. The mean annual changes in refractive error for hyperopes (-0.13 ± 0.44 D, N=15), emmetropes (-0.26 ± 0.37 D, N=17), and myopes (-0.75 ± 0.77 D, N=18) were similar to values reported in the literature for nonexotropic children.

Myopia Progression in Children Wearing Spectacles vs. Switching to Contact Lenses.

Purpose. To investigate myopia progression in Correction of Myopia Evaluation Trial (COMET) participants who switched to soft contact lenses (CLs) vs. remained in spectacles after the clinical trial ended. Methods. Four hundred sixty-nine ethnically diverse, 6- to 11-year-old myopic children were randomly assigned to wear single vision lenses (SVLs) or progressive addition spectacle lenses (PALs) for 5 years as part of COMET. Afterwards they could choose another lens type, including CLs. Data in this article are from 286 participants who wore their original spectacle lenses for 6 years (n = 199) or wore CLs most or all the time between the 5- and 6-year visits (n = 87). Refractive error and axial length (AL) were measured after cycloplegia with 1% Tropicamide. The primary outcome was myopia progression between the 5- and 6-year visits. Two-year myopia progression was evaluated in a subset of 183 participants who wore the same lens type for an additional year. Myopia progression and AL were compared between the two lens groups using multiple linear regression. Results. Participants in the two groups were similar with respect to age, ethnicity, myopia at 5-years, accommodation and phoria, but more girls switched to CLs than remained in spectacles (p < 0.0001). Mean (±SD) myopia progression was higher (p = 0.003) after 1 year in the CL group [−0.28 ± 0.33 diopter (D)] than the spectacle group (−0.14 ± 0.36 D), and remained higher after 2 years in the 2-year subset (−0.52 ± 0.46 D vs. −0.25 ± 0.39 D, p < 0.0001). Results were similar after adjustment for related factors. No significant differences in AL were found between groups after adjustment. Corneal curvature remained unchanged in both groups. Conclusions. COMET children switching from glasses to CLs experienced a small, statistically significant but clinically inconsequential increase in myopia progression.