Astigmatism progression in the early treatment for retinopathy of prematurity study to 6 years of age.

PURPOSE: To examine the prevalence of astigmatism (≥ 1.00 diopter [D]) and high astigmatism (≥ 2.00 D) from 6 months after term due date to 6 years of age in preterm children with birth weight of less than 1251 g in whom high-risk prethreshold retinopathy of prematurity (ROP) developed and who participated in the Early Treatment for ROP study. DESIGN: Observational cohort study. PARTICIPANTS: Four hundred one infants in whom high-risk prethreshold ROP developed in 1 or both eyes and were randomized to early treatment (ET) versus conventional management (CM). Refractive error was measured by cycloplegic retinoscopy. Eyes were excluded if they underwent additional retinal, glaucoma, or cataract surgery. INTERVENTION: Eyes were randomized to receive laser photocoagulation at high-risk prethreshold ROP or to receive treatment only if threshold ROP developed. MAIN OUTCOME MEASURES: Astigmatism and high astigmatism at each study visit. RESULTS: For both ET and CM eyes, there was a consistent increase in prevalence of astigmatism over time, increasing from 42% at 4 years to 52% by 6 years for the group of ET eyes and from 47% to 54%, respectively, in the CM eyes. There was no statistically significant difference between the slopes (rate of change per month) of the ET and CM eyes for both astigmatism and high astigmatism (P = 0.75). CONCLUSIONS: By 6 years of age, astigmatism of 1.00 D or more developed in more than 50% of eyes with high-risk prethreshold ROP, and nearly 25% of such eyes had high astigmatism (≥ 2.00 D). Presence of astigmatism was not influenced by timing of treatment, zone of acute-phase ROP, or presence of plus disease. However, there was a trend toward higher prevalence of astigmatism and high astigmatism in eyes with ROP residua. Most astigmatism was with-the-rule (75°-105°). More eyes with type 2 than type 1 ROP had astigmatism by 6 years. These findings reinforce the need for follow-up eye examinations through early grade school years in infants with high-risk prethreshold ROP. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Retinopathy of prematurity in infants weighing less than 500 grams at birth enrolled in the early treatment for retinopathy of prematurity study.

PURPOSE: To describe patient characteristics, classification, and onset of prethreshold retinopathy of prematurity (ROP), and ocular findings at 6 months corrected age in infants with birth weights <500 g who were enrolled in the Early Treatment for Retinopathy of Prematurity (ETROP) Study. DESIGN: Multicenter randomized clinical trial. PARTICIPANTS: Sixty-three infants with birth weights <500 g who developed ROP and were enrolled in the ETROP Study. METHODS: Infants <1251 g at birth were logged at 26 study centers from October 1, 2000, to September 30, 2002, and underwent examinations for ROP. Infants who developed ROP and whose parents/legal guardians consented were enrolled in the ETROP Study. Infants who developed high-risk prethreshold ROP were randomized; 1 eye was treated early with peripheral retinal ablation and the other eye was managed conventionally, or, in asymmetric cases, the high-risk eye was randomized to early peripheral retinal ablation or conventional management. All eyes reaching prethreshold ROP were examined when infants reached 6 months corrected age. MAIN OUTCOME MEASURES: Retinopathy of prematurity incidence, characteristics, and ocular findings among participants. RESULTS: Thirty-four infants reached prethreshold or worse severity in 1 or both eyes. Retinopathy of prematurity was located in zone I in 43.3% of all prethreshold eyes, and plus disease was present in 46.7%. Median postmenstrual age for diagnosis of all prethreshold ROP was 36.1 weeks, but earlier (35.1 weeks) for eyes that developed high-risk prethreshold ROP. In the 27 surviving infants with prethreshold ROP, ophthalmic examination at 6 months corrected age showed a normal posterior pole in 22 (81.5%), a favorable structural outcome with posterior pole abnormalities in 4 (14.8%), and an unfavorable structural outcome (stage 4B) in 1 (3.7%). One infant developed amblyopia, 4 infants developed nystagmus, 4 infants developed strabismus, and 8 infants developed myopia >-5.00 diopters. CONCLUSIONS: This is the first report on characteristics of prethreshold ROP in infants with birth weights <500 g. These infants are at high risk for developing prethreshold ROP, although many initially achieve a favorable structural outcome. They are at risk of developing strabismus, nystagmus, high myopia, and abnormal retinal structure and should therefore receive continued long-term follow-up. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Prevalence of astigmatism in Native American infants and children.

PURPOSE: To describe the prevalence of high astigmatism in infants and young children who are members of a Native American tribe with a high prevalence of astigmatism. METHODS: SureSight autorefraction measurements were obtained for 1461 Tohono O'odham children aged 6 months to 8 years. RESULTS: The prevalence of astigmatism >2.00 diopters was 30% in Tohono O'odham children during infancy (6 months to <1 year of age) and was 23 to 29% at ages 2 to 7 years. However, prevalence dipped to 14% in children 1 to <2 years of age. At all ages, axis of astigmatism was with-the-rule (plus cylinder axis 90 degrees +/- 30 degrees ) in at least 94% of cases. CONCLUSIONS: As in non-Native American populations, Tohono O'odham infants show a high prevalence of astigmatism, which decreases in the second year of life. However, the prevalence of high astigmatism in Tohono O'odham children increases by age 2 to <3 years to a level near that seen in infancy and remains at that level until at least age 8 years. Longitudinal data are needed to determine whether the increase in high astigmatism after infancy occurs in infants who had astigmatism as infants or is due to the development of high astigmatism in children who did not show astigmatism during infancy.

Amblyopia in astigmatic infants and toddlers.

PURPOSE: To determine whether reduced astigmatism-corrected acuity for vertical (V) and/or horizontal (H) gratings and/or meridional amblyopia (MA) are present before 3 years of age in children who have with-the-rule astigmatism. METHODS: Subjects were 448 children, 6 months through 2 years of age with no known ocular abnormalities other than with-the-rule astigmatism, who were recruited through Women, Infants and Children clinics on the Tohono O'odham reservation. Children were classified as non-astigmats (< or =2.00 diopters) or astigmats (>2.00 diopters) based on right eye non-cycloplegic autorefraction measurements (Welch Allyn SureSight). Right eye astigmatism-corrected grating acuity for V and H stimuli was measured using the Teller Acuity Card procedure while children wore cross-cylinder lenses to correct their astigmatism or plano lenses if they had no astigmatism. RESULTS: Astigmatism-corrected acuity for both V and H gratings was significantly poorer in the astigmats than in the non-astigmats, and the reduction in acuity for astigmats was present for children in all three age groups examined (6 months to <1 year, 1 to <2 years, and 2 to <3 years). There was no significant difference in V-H grating acuity (no evidence of MA) for the astigmatic group as a whole, or when data were analyzed for each age group. CONCLUSIONS: Even in the youngest age group, astigmats tested with astigmatism correction showed reduced acuity for both V and H gratings, which suggests that astigmatism is having a negative influence on visual development. We found no evidence of orientation-related differences in astigmatism-corrected grating acuity, indicating either that MA does not develop before 3 years of age, or that most of the astigmatic children had a type of astigmatism, i.e., hyperopic, that has proven to be less likely than myopic or mixed astigmatism to result in MA.

Astigmatism in the Early Treatment for Retinopathy Of Prematurity Study: findings to 3 years of age.

PURPOSE: To examine the prevalence of astigmatism (> or =1.00 diopter [D]) and high astigmatism (> or =2.00 D) at 6 and 9 months corrected age and 2 and 3 years postnatal age, in preterm children with birth weight of less than 1251 g in whom high-risk prethreshold retinopathy of prematurity (ROP) developed and who participated in the Early Treatment for Retinopathy of Prematurity (ETROP) Study. DESIGN: Randomized, controlled clinical trial. PARTICIPANTS: Four hundred one infants in whom prethreshold ROP developed in one or both eyes and who were randomized after they were determined to have a high risk (> or =15%) of poor structural outcome without treatment using the Risk Management of Retinopathy of Prematurity (RM-ROP2) program. Refractive error was measured by cycloplegic retinoscopy. Eyes with additional retinal, glaucoma, or cataract surgery were excluded. INTERVENTION: Eyes were randomized to receive laser photocoagulation at high-risk prethreshold ROP (early treated [ET]) or to be conventionally managed (CM), receiving treatment only if threshold ROP developed. MAIN OUTCOME MEASURES: Astigmatism and high astigmatism at each visit. Astigmatism was classified as with-the-rule (WTR; 75 degrees -105 degrees ), against-the-rule (ATR; 0 degrees -15 degrees and 165 degrees -180 degrees ), or oblique (OBL; 16 degrees -74 degrees and 106 degrees -164 degrees ). RESULTS: The prevalence of astigmatism in ET and CM eyes was similar at each test age. For both groups, there was an increase in prevalence of astigmatism from approximately 32% at 6 months to approximately 42% by 3 years, mostly occurring between 6 and 9 months. Among eyes that could be refracted, astigmatism was not influenced by zone of acute-phase ROP, presence of plus disease, or retinal residua of ROP. Eyes with astigmatism and high astigmatism most often had WTR astigmatism. CONCLUSIONS: By age 3 years, nearly 43% of eyes treated at high-risk prethreshold ROP developed astigmatism of > or =1.00 D and nearly 20% had astigmatism of > or =2.00 D. Presence of astigmatism was not influenced by timing of treatment of acute-phase ROP or by characteristics of acute-phase or cicatricial ROP. These findings reinforce the need for follow-up eye examinations in infants with high-risk prethreshold ROP. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Optical treatment reduces amblyopia in astigmatic children who receive spectacles before kindergarten.

OBJECTIVE: To examine the effect of spectacle correction of astigmatism during preschool on best-corrected recognition visual acuity (VA), grating VA, and meridional amblyopia (difference between acuity for vertical versus horizontal gratings) once the children reach kindergarten. DESIGN: Comparative case series. PARTICIPANTS: Seventy-three astigmatic (right eye > or =1.50 diopters [D] cylinder) Native American (Tohono O'odham) children 5 to 7 years of age. All had with-the-rule astigmatism. In 28 children, the astigmatism was simple myopic, compound myopic, or mixed (M/MA), and in 45 children, it was simple or compound hyperopic (HA). INTERVENTION: Thirty-nine children (Treated Group) had spectacle correction of refractive error, prescribed for full-time wear, in preschool (0.8-2.4 years before testing). Thirty-four children (Untreated Group) had no prior correction. MAIN OUTCOME MEASURE: Comparison of Treated versus Untreated Groups for mean best-corrected right-eye recognition VA, measured with the Early Treatment Diabetic Retinopathy Study (ETDRS) chart and the Lea Symbols chart, for grating VA, measured with modified Teller acuity card stimuli, and for meridional amblyopia, based on grating acuity results. RESULTS: Mean ETDRS VA was significantly better in the Treated Group (20/37) than in the Untreated Group (20/48; P<0.003), but the difference between mean Lea Symbols VA in the Treated Group (20/33) and in the Untreated Group (20/38) was not significant. No significant Treated versus Untreated Group differences were found for either vertical or horizontal grating acuity. Meridional amblyopia differed between the M/MA group, which showed better acuity for vertical than for horizontal gratings, and the HA group, which showed better acuity for horizontal than for vertical gratings. However, in neither the M/MA group nor the HA group was there a significant difference in magnitude of meridional amblyopia in the Treated versus the Untreated Group. CONCLUSIONS: Spectacle correction during the preschool years results in a significant improvement in best-corrected letter recognition acuity in astigmatic children by the time they reach kindergarten. However, grating acuity was not improved and magnitude of meridional amblyopia was not reduced in children who had received early spectacle correction. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Normative monocular visual acuity for early treatment diabetic retinopathy study charts in emmetropic children 5 to 12 years of age.

OBJECTIVE: To provide normative data for children tested with Early Treatment Diabetic Retinopathy Study (ETDRS) charts. DESIGN: Cross-sectional study. PARTICIPANTS: A total of 252 Native American (Tohono O'odham) children aged 5 to 12 years. On the basis of cycloplegic refraction conducted on the day of testing, all were emmetropic (myopia < or =0.25 diopter [D] spherical equivalent, hyperopia < or =1.00 D spherical equivalent, and astigmatism < or =0.50 D in both eyes). METHODS: Monocular visual acuity was tested at 4 m, using 1 ETDRS chart for the right eye (RE) and another for the left eye (LE). MAIN OUTCOME MEASURES: Visual acuity was scored as the total number of letters correctly identified, by naming or matching to letters on a lap card, and as the smallest letter size for which the child identified 3 of 5 letters correctly. RESULTS: Visual acuity results did not differ for the RE versus the LE, so data are reported for the RE only. Mean visual acuity for 5-year-olds (0.16 logarithm of the minimum angle of resolution [logMAR] [20/29]) was significantly worse than for 8-, 9-, 10-, 11-, and 12-year-olds (0.05 logMAR [20/22] or better at each age). The lower 95% prediction limit for determining whether a child has visual acuity within the normal range was 0.38 (20/48) for 5-year-olds and 0.30 (20/40) for 6- to 12-year-olds, which was reduced to 0.32 (20/42) for 5-year-olds and 0.21 (20/32) for 6- to 12-year-olds when recalculated with outlying data points removed. Mean interocular acuity difference did not vary by age, averaging less than 1 logMAR line at each age, with a lower 95% prediction limit of 0.17 log unit (1.7 logMAR lines) across all ages. CONCLUSIONS: For monocular visual acuity based on ETDRS charts to be in the normal range, it must be better than 20/50 for 5-year-olds and better than 20/40 for 6- to 12-year-olds. Normal interocular acuity difference includes values of less than 2 logMAR lines. Normative ETDRS visual acuity values are not as good as norms reported for adults, suggesting that a child's visual acuity results should be compared with norms based on data from children, not with adult norms.

Progression of myopia and high myopia in the early treatment for retinopathy of prematurity study: findings to 3 years of age.

PURPOSE: Examine the prevalence of myopia and high myopia, at 6 and 9 months postterm and 2 and 3 years postnatal in preterm children with birth weights < 1251 g who developed high-risk prethreshold retinopathy of prematurity (ROP) in the neonatal period and participated in the Early Treatment for ROP Study. DESIGN: Randomized controlled clinical trial. PARTICIPANTS: Four hundred one infants who developed prethreshold ROP and were determined to have a significant risk (>/=15%) of poor structural outcomes without treatment. Children underwent cycloplegic retinoscopy at examinations between 6 months postterm and 3 years' postnatal age. INTERVENTION: Eyes were randomized to receive treatment at high-risk prethreshold ROP (early treated [ET]) or conventional management (CM), with treatment only if threshold ROP developed. MAIN OUTCOME MEASURES: Myopia (spherical equivalent >/= 0.25 diopters [D]) or high myopia (>/=5.00 D) at each visit. RESULTS: Prevalences of myopia were similar in treated eyes in the ET and CM groups, increasing from approximately 58% to 68% between 6 and 9 months, with little change thereafter. Both ET and CM eyes showed an increasing prevalence of high myopia, approximately 19% at 6 months and increasing 4% to 8% at successive examinations. Zone of ROP and presence or absence of plus disease had little effect on prevalence of myopia or high myopia between ages 6 months and 3 years. However, eyes with ROP residua (straightened temporal vessels or macular heterotopia) showed a higher prevalence of myopia and high myopia than eyes without residua. CONCLUSIONS: Approximately 70% of high-risk prethreshold ROP eyes were myopic in early childhood, and the proportion with high myopia increased steadily between ages 6 months and 3 years. Timing of treatment of high-risk prethreshold ROP did not influence refractive error development. There was little difference in prevalence of myopia or high myopia between eyes with zone I and eyes with zone II ROP, nor between eyes with plus disease and eyes with no plus disease. However, prevalence of myopia and high myopia was higher in eyes with retinal residua of ROP than in eyes with normal-appearing posterior poles, highlighting the importance of follow-up eye examinations of infants who had prethreshold ROP.

Changes in visual function following optical treatment of astigmatism-related amblyopia.

Effects of optical correction on best-corrected grating acuity (vertical (V), horizontal (H), oblique (O)), vernier acuity (V, H, O), contrast sensitivity (1.5, 6.0, and 18.0 cy/deg spatial frequency, V and H), and stereoacuity were evaluated prospectively in 4- to 13-year-old astigmats and a non-astigmatic age-matched control group. Measurements made at baseline (eyeglasses dispensed for astigmats), 6 weeks, and 1 year showed greater improvement in astigmatic than non-astigmatic children for all measures. Treatment effects occurred by 6 weeks, and did not differ by cohort (<8 vs. >or= 8 years), but astigmatic children did not attain normal levels of visual function.

Optical treatment of amblyopia in astigmatic children: the sensitive period for successful treatment.

OBJECTIVE: To compare the effectiveness of eyeglass treatment of astigmatism-related amblyopia in children younger than 8 years (range, 4.75-7.99 years) versus children 8 years of age and older (range, 8.00-13.53 years) over short (6-week) and long (1-year) treatment intervals. DESIGN: Prospective, interventional, comparative case-control study. PARTICIPANTS: Four hundred forty-six nonastigmatic (right and left eye, <0.75 diopters [D]) and 310 astigmatic (RE, > or =1.00 D) Native American (Tohono O'odham) children in kindergarten or grades 1 through 6. INTERVENTION: Eyeglass correction of refractive error, prescribed for full-time wear, in astigmatic children. MAIN OUTCOME MEASURES: Amount of change in mean right-eye best-corrected letter visual acuity for treated astigmatic children versus untreated, age-matched nonastigmatic children after short (6-week) and long (1-year) treatment intervals. RESULTS: Astigmatic children had significantly reduced mean best-corrected visual acuity at baseline compared to nonastigmatic children. Astigmats showed significantly greater improvement in mean best-corrected visual acuity (0.08 logarithm of the minimum angle of resolution [logMAR] unit; approximately 1 line), than the nonastigmatic children (0.01 logMAR unit) over the 6-week treatment interval. No additional treatment effect was observed between 6 weeks and 1 year. Treatment effectiveness was not dependent on age group (<8 years vs. > or =8 years) and was not influenced by previous eyeglass treatment. Despite significant improvement, mean best-corrected visual acuity in astigmatic children remained significantly poorer than in nonastigmatic children after 1 year of eyeglass treatment, even when analyses were limited to results from highly compliant children. CONCLUSIONS: Sustained eyeglass correction results in significant improvement in best-corrected visual acuity in astigmatic children, including those previously believed to be beyond the sensitive period for successful treatment.

Amblyopia in astigmatic children: patterns of deficits.

Neural changes that result from disruption of normal visual experience during development are termed amblyopia. To characterize visual deficits specific to astigmatism-related amblyopia, we compared best-corrected visual performance in 330 astigmatic and 475 non-astigmatic kindergarten through 6th grade children. Astigmatism was associated with deficits in letter, grating and vernier acuity, high and middle spatial frequency contrast sensitivity, and stereoacuity. Although grating acuity, vernier acuity, and contrast sensitivity were reduced across stimulus orientation, astigmats demonstrated orientation-dependent deficits (meridional amblyopia) only for grating acuity. Astigmatic children are at risk for deficits across a range of visual functions.

Severe visual impairment in children with mild or moderate retinal residua following regressed threshold retinopathy of prematurity.

PURPOSE: To describe clinical features of patients from the Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) trial who, after developing severe ROP in infancy, had minimal or moderate retinal residua in at least one eye but a visual acuity of worse than 20/200 in both eyes at the 10 year examination. METHODS: Data from the 10 year CRYO-ROP Trial follow-up exams were evaluated to identify all patients with retinal outcomes of no retinopathy of prematurity (ROP) residua, straightened temporal vessels, or macular heterotopia in at least one eye, but visual acuity less than 20/200 in both eyes. Presence of optic atrophy, nystagmus, and optic disk cupping and developmental survey results were examined. RESULTS: Of 247 patients examined at 10 years, 16 met our inclusion criteria. At the last age at which the following data were recorded, seven had optic atrophy at the 10 year examination, one had optic disk cupping >0.5 at the 5(1/2) year examination, and eight had nystagmus under binocular conditions at the 24 month examination. Nine patients had a below-normal developmental test score on the Functional Independence Measure for Children (WeeFIM). After clinical data interpretation, we concluded that the predominant cause of visual impairment was postgeniculate disease in five patients, ROP in six patients, and combined anterior and posterior visual pathway disease in two patients; in three patients data were insufficient to make a determination. CONCLUSIONS: Poor visual function with mild to moderate retinal residua of severe ROP in at least one eye is relatively rare. In such patients, anterior, posterior, or combined visual pathway disease can occur.

Proceedings of the Third International Symposium on Retinopathy of Prematurity: an update on ROP from the lab to the nursery (November 2003, Anaheim, California).

The Third International Symposium on Retinopathy of Prematurity (ROP) was convened with the aim of cross fertilizing the horizons of basic and clinical scientists with an interest in the pathogenesis and management of infants with ROP. Ten speakers in the clinical sciences and ten speakers in the basic sciences were recruited on the basis of their research to provide state of the art talks. The meeting was held November 9, 2003 immediately prior to the American Academy of Ophthalmology meeting; scholarships were provided for outreach to developing countries and young investigators. This review contain the summaries of the 20 platform presentations prepared by the authors and the abstracts of presented posters. Each author was asked to encapsulate the current state of understanding, identify areas of controversy, and make recommendations for future research. The basic science presentations included insights into the development of the human retinal vasculature, animal models for ROP, growth factors that affect normal development and ROP, and promising new therapeutic approaches to treating ROP like VEGF targeting, inhibition of proteases, stem cells, ribozymes to silence genes, and gene therapy to deliver antiangiogenic agents. The clinical presentations included new insights into oxygen management, updates on the CRYO-ROP and ETROP studies, visual function in childhood following ROP, the neural retina in ROP, screening for ROP, management of stage 3 and 4 ROP, ROP in the third world, and the complications of ROP in adult life. The meeting resulted in a penetrating exchange between clinicians and basic scientists, which provided great insights for conference attendees. The effect of preterm delivery on the normal cross-talk of neuroretinal and retinal vascular development is a fertile ground for discovering new understanding of the processes involved both in normal development and in retinal neovascular disorders. The meeting also suggested promising potential therapeutic interventions on the horizon for ROP.

Visual acuity at 10 years in Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) study eyes: effect of retinal residua of retinopathy of prematurity.

OBJECTIVE: To describe recognition (letter) acuity at age 10 years in eyes with and without retinal residua of retinopathy of prematurity (ROP). DESIGN: Presence and severity of ROP residua were documented by a study ophthalmologist. Masked testers measured monocular recognition visual acuity (Early Treatment of Diabetic Retinopathy Study) when the children were 10 years old. Two hundred forty-seven of 255 surviving Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) randomized trial patients participated. A reference group of 102 of 104 Philadelphia-based CRYO-ROP study participants who did not develop ROP was also tested. RESULTS: More severe retinal residua were associated with worse visual acuity, regardless of whether retinal ablation was performed to treat the severe acute-phase ROP. However, within each ROP residua category, there was a wide range of visual acuity results. CONCLUSIONS: This is the first report of the relation between visual acuity (Early Treatment of Diabetic Retinopathy Study charts) and structural abnormalities related to ROP in a large group of eyes that developed threshold ROP in the perinatal period. Visual deficits are greater in eyes with more severe retinal residua than in eyes with mild or no residua. However, severity of ROP residua does not predict the visual acuity of an individual eye because within a single residua category, acuity may range from near normal to blind.

Prevalence and course of strabismus in the first year of life for infants with prethreshold retinopathy of prematurity: findings from the Early Treatment for Retinopathy of Prematurity study.

OBJECTIVE: To present strabismus data for premature infants with prethreshold retinopathy of prematurity (ROP) enrolled in the Early Treatment for Retinopathy of Prematurity study. DESIGN: The prevalence of strabismus was tabulated for all of the infants with high-risk prethreshold disease who participated in the randomized trial of the Early Treatment for Retinopathy of Prematurity study and were examined at 6 and/or 9 months' corrected age as well as for all of the infants with low-risk prethreshold disease who were examined at 6 months' corrected age. MAIN OUTCOME MEASURES: Presence or absence of strabismus at 6 and 9 months' corrected age. RESULTS: The prevalence of strabismus at 6 months was higher for infants with high-risk prethreshold ROP than for those with low-risk prethreshold ROP (20.3% vs 9.6%, respectively; P<.001). Risk factors associated with the development of strabismus at 9 months include abnormal fixation behavior, presence of amblyopia, and outborn birth status (ie, born outside of a study-affiliated hospital). At 9 months, 30% of infants with high-risk prethreshold ROP had strabismus, although only 42% showed strabismus at 6 months. Thirty percent of infants with strabismus at 6 months showed normal alignment at 9 months. CONCLUSIONS: Infants with high-risk prethreshold ROP show significant variability in the presence vs absence of strabismus in the first year of life; thus, conservative management is recommended. APPLICATION TO CLINICAL PRACTICE: Ophthalmologists managing strabismus in infants who have high-risk prethreshold ROP should be aware of the significant variability in ocular alignment during the first year of life.

Teller Acuity Card norms with and without use of a testing stage.

PURPOSE: To determine whether norms obtained using the Teller Acuity Card stage are appropriate for comparison with results obtained when the stage is not used. METHODS: Eighty children were tested, 20 each at 3.5, 11, 17, and 30 months of age. Binocular grating acuity was measured once with Teller Acuity Cards presented with the stage and once without the stage. Test order was counterbalanced across subjects. Testers were aware that gratings progressed from lower to higher spatial frequencies, but were masked to the absolute spatial frequency of the grating on each card. Testers were masked to acuity results until the child completed testing. RESULTS: Repeated measures ANOVA with age as a between-subjects variable and test setting as a within-subjects variable showed a significant effect of age (p < 0.001) and test setting (p < 0.001), and a significant interaction between age and test setting (p < 0.01). Post-hoc comparisons (with Bonferroni correction) showed that the difference in acuity results obtained with the stage versus without the stage was significant at 17 months (p < 0.05), but not at 3.5, 11, or 30 months. CONCLUSIONS: Grating acuity norms obtained with the Teller Acuity Card stage are appropriate for comparison with data obtained without the stage in children 3.5, 11, and 30 months of age. However, when 17-month-old children are tested without the stage, comparison of results with norms obtained with the stage is problematic, because testing without the stage results in reduced acuity scores in this age group.

Random Dot E stereotest: testability and reliability in 3- to 5-year-old children.

PURPOSE: To determine the proportion of preschoolers testable with the Random Dot E (RDE) stereotest and the between-tester reliability. METHODS: Subjects were 1257 3- to 5-year-olds who were participants in Head Start programs in five communities. The sample was over-weighted with children who failed the routine Head Start vision screening (58% failures; 42% nonfailures). Each child had stereotesting attempted by two licensed eye care professionals using the RDE test, first in a screening setting and later in a comprehensive eye examination. Pretesting was performed at 50 cm. Children who discriminated between the nonstereo E and blank cards on 4 of 4 or 4 of 5 presentations were considered testable. Stereotesting was conducted at 50, 100, and 150 cm corresponding to 504, 252, and 168 arcsec disparity). Extent of agreement beyond chance between the screening and examination test results was assessed using the kappa (kappa) and weighted kappa (kappa(w)) statistics. RESULTS: Testability increased with age at both the first (86% of 3-, 89% of 4-, and 93% of 5-year-olds; p = 0.02) and the second (90% of 3-, 94% of 4-, and 98% of 5-year-olds; p = 0.0001) sessions. Overall, stereopsis was better at the second session. Agreement between sessions was moderate (kappa(w) = 0.43; 59% identical scores). While identical scores increased with age (53% of 3-, 59% of 4-, and 63% of 5-year-olds), kappa(w) statistics did not differ with age (p = 0.49). CONCLUSIONS: Child testability on the RDE stereotest was significantly better for older than younger preschool-age children. Overall, test-retest agreement was moderate and did not differ according to age. Testability rates of 98% and higher have been achieved in the same population with other screening tests including another random dot stereotest.

Prevalence of myopia at 9 months in infants with high-risk prethreshold retinopathy of prematurity.

PURPOSE: To examine the prevalence of myopia and high myopia at 9 months corrected age in premature infants who participated in the multicenter randomized trial of Early Treatment for Retinopathy of Prematurity (ETROP). DESIGN: Randomized, controlled clinical trial. PARTICIPANTS: Four hundred one infants with birth weights of <1251 g in whom prethreshold ROP developed in one or both eyes and who were determined to have a significant risk (> or =15%) of poor structural outcomes without treatment, based on the risk management for ROP program. INTERVENTION: Infants with bilateral high-risk prethreshold ROP (n = 317) had 1 eye randomized to early treatment, and the fellow eye was managed conventionally. In asymmetric cases (n = 84), the eye with high-risk prethreshold ROP was randomized to early treatment or conventional management (control). Eyes randomized to early treatment at high-risk prethreshold ROP and eyes randomized to conventional management in which threshold ROP developed received peripheral retinal photocoagulation or cryotherapy. Conventionally managed eyes in which threshold ROP did not develop were observed. Cycloplegic retinoscopy data were obtained at 9 months corrected age from 321 eyes treated early and 307 eyes managed conventionally. MAIN OUTCOME MEASURES: Prevalence of myopic (spherical equivalent > or = 0.25 diopters [D]) and highly myopic (> or =5.00 D) eyes in each group. RESULTS: The prevalence of myopia (64.5% vs. 69.4%; P = 0.06) and high myopia (25.5% vs. 28.3%; P = 0.20) was similar between eyes treated at high-risk prethreshold and high-risk prethreshold eyes managed conventionally. Among high-risk eyes managed conventionally, the prevalence of myopia (78.2% vs. 53.3%) and high myopia (37.6% vs. 11.2%) was higher when threshold ROP developed than when regression without treatment occurred. Among eyes treated at high-risk prethreshold ROP, the prevalence of myopia (93.3% vs. 91.7% vs. 60.6%) and of high myopia (53.3% vs. 33.3% vs. 20.8%) was higher in eyes with abnormal angle of temporal retinal vessels or macular ectopia than in eyes with no retinal residua. This also held true for conventionally managed eyes. CONCLUSIONS: Early treatment at high-risk prethreshold did not place eyes at greater risk of myopia and high myopia than did conventional management of eyes with high-risk prethreshold ROP.

15-year outcomes following threshold retinopathy of prematurity: final results from the multicenter trial of cryotherapy for retinopathy of prematurity.

OBJECTIVE: To report the ocular structure and visual acuity outcomes at age 15 years, and the incidence of retinal detachment between 10 and 15 years of age, for patients in the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity (CRYO-ROP). METHODS: Subjects were 254 survivors from 291 preterm children with birth weights less than 1251 g and severe (threshold) retinopathy of prematurity (ROP) in one or both eyes, who participated in the CRYO-ROP trial. At age 15 years, unfavorable ocular structure was posterior retinal fold or worse judged by study-certified ophthalmologists. Unfavorable distance visual acuity was 20/200 or worse measured by study-certified testers using Early Treatment of Diabetic Retinopathy Study recognition acuity charts. RESULTS: Thirty percent of treated eyes and 51.9% of control eyes (P<.001) had unfavorable structural outcomes. Between 10 and 15 years of age, new retinal folds, detachments, or obscuring of the view of the posterior pole occurred in 4.5% of treated and 7.7% of control eyes. Unfavorable visual acuity outcomes were found in 44.7% of treated and 64.3% of control eyes (P<.001). CONCLUSION: The benefit of cryotherapy for treatment of threshold ROP, for both structure and visual function, was maintained across 15 years of follow-up. New retinal detachments, even in eyes with relatively good structural findings at age 10 years, suggest value in long-term, regular follow-up of eyes that experience threshold ROP.

Are norms based on the original Teller Acuity Cards appropriate for use with the new Teller Acuity Cards II?

PURPOSE: We sought to compare visual acuity results obtained with the original Teller Acuity Cards (TAC), which are no longer commercially available, and the modified, laminated Teller Acuity Cards II (TAC II), which recently became commercially available. METHODS: Sixty children were tested, 20 at each of 3 ages: 3.5 months, 11 months, and 30 months. Each subject's binocular grating acuity was measured once with the TAC and once with the TAC II, with the order of testing counterbalanced across subjects. Testers were aware that acuity cards were arranged in ascending order of spatial frequency, but they were masked to the absolute spatial frequencies of the gratings in the subset of cards used. Testers were also masked to acuity results until testing of the child was completed. RESULTS: Repeated-measures analysis of variance with age as a between-subjects variable and card type as a within-subjects variable showed a significant effect of age (P < 0.001) and a significant effect of card type (P < 0.001), but no interaction between age and card type. Post hoc comparisons (with Bonferroni correction) showed that mean acuity score was significantly better with TAC than with TAC II at 3.5 months (0.2 octave, P < 0.05), 11 months (0.4 octave, P < 0.01), and 30 months (0.7 octave, P < 0.001). CONCLUSIONS: These results suggest that normative grating acuity data obtained with the original Teller Acuity Cards need to be adjusted toward lower acuity values by approximately 0.5 octave to be appropriate for use with the new Teller Acuity Cards II.