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Purpose: To survey paediatric eye care providers to identify current patterns of prescribing for hyperopia., Methods: Paediatric eye care providers were invited, via email, to participate in a survey to evaluate current age-based refractive error prescribing practices. Questions were designed to determine which factors may influence the survey participant's prescribing pattern (e.g., patient's age, magnitude of hyperopia, patient's symptoms, heterophoria and stereopsis) and if the providers were to prescribe, how much hyperopic correction would they prescribe (e.g., full or partial prescription). The response distributions by profession (optometry and ophthalmology) were compared using the Kolmogorov-Smirnov cumulative distribution function test., Results: Responses were submitted by 738 participants regarding how they prescribe for their hyperopic patients. Most providers within each profession considered similar clinical factors when prescribing. The percentages of optometrists and ophthalmologists who reported considering the factor often differed significantly. Factors considered similarly by both optometrists and ophthalmologists were the presence of symptoms (98.0%, p = 0.14), presence of astigmatism and/or anisometropia (97.5%, p = 0.06) and the possibility of teasing (8.3%, p = 0.49). A wide range of prescribing was observed within each profession, with some providers reporting that they would prescribe for low levels of hyperopia while others reported that they would never prescribe. When prescribing for bilateral hyperopia in children with age-normal visual acuity and no manifest deviation or symptoms, the threshold for prescribing decreased with age for both professions, with ophthalmologists typically prescribing 1.5-2 D less than optometrists. The threshold for prescribing also decreased for both optometrists and ophthalmologists when children had associated clinical factors (e.g., esophoria or reduced near visual function). Optometrists and ophthalmologists most commonly prescribed based on cycloplegic refraction, although optometrists most commonly prescribed based on both the manifest and cycloplegic refraction for children ≥7 years., Conclusion: Prescribing patterns for paediatric hyperopia vary significantly among eye care providers., (© 2023 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)

Background: Costello syndrome (CS) is a multisystem developmental disorder caused by germline pathogenic variants in HRAS resulting in dysregulation of the Ras pathway. A systematic characterization of ophthalmic manifestations provides a unique opportunity to understand the role of Ras signal transduction in ocular development and guide optimal ophthalmic care in CS individuals., Methods: Visual function, ocular features and genotype/phenotype correlations were evaluated in CS individuals harboring HRAS pathogenic variants, by cross-sectional and retrospective studies, and were recruited through the Costello Syndrome Family Network (CSFN) between 2007 and 2020., Results: Fifty-six molecularly diagnosed CS individuals including 34 females and 22 males, ages ranging from 0.5 to 37 years were enrolled. The most common ophthalmic manifestations in the cross-sectional study were lack of stereopsis (96%), refractive errors (83%), strabismus (72%), nystagmus (69%), optic nerve hypoplasia or pallor (55%) and ptosis (13.7%) with higher prevalence than in the retrospective data (refractive errors (41%), strabismus (44%), nystagmus (26%), optic nerve hypoplasia or pallor (7%) and ptosis (11%)). Visual acuities were found to ranged from 20/25 to 20/800 and contrast sensitivity from 1.6% to 44%. HRAS pathogenic variants included p.G12S (84%), p.G13C (7%), p.G12A (5.4%), p.G12C (1.8%) and p.A146V (1.8%)., Conclusion: Majority of individuals with CS have refractive errors, strabismus, nystagmus, absent stereopsis, and optic nerve abnormalities suggesting that HRAS and the Ras pathway play a vital role in visual system development. Ptosis, refractive errors and strabismus are amenable to treatment and early ophthalmic evaluation is crucial to prevent long-term vision impairment and improve overall quality of life in CS.

Abstract: This review summarizes clinically relevant outcomes from the Vision in Preschoolers (VIP) and VIP-Hyperopia in Preschoolers (VIP-HIP) studies. In VIP, refraction tests (retinoscopy, Retinomax, SureSight) and Lea Symbols Visual Acuity performed best in identifying children with vision disorders. For lay screeners, Lea Symbols single, crowded visual acuity (VA) testing (VIP, 5-foot) was significantly better than linear, crowded testing (10-foot). Children unable to perform the tests (<2%) were more likely to have vision disorders than children who passed and should be referred for vision evaluation. Among racial/ethnic groups, the prevalence of amblyopia and strabismus was similar while that of hyperopia, astigmatism, and anisometropia varied. The presence of strabismus and significant refractive errors were risk factors for unilateral amblyopia, while bilateral astigmatism and bilateral hyperopia were risk factors for bilateral amblyopia. A greater risk of astigmatism was associated with Hispanic, African American, and Asian race, and myopic and hyperopic refractive error. The presence and severity of hyperopia were associated with higher rates of amblyopia, strabismus, and other associated refractive error. In the VIP-HIP study, compared to emmetropes, meaningful deficits in early literacy were observed in uncorrected hyperopic 4- and 5-year-olds [≥+4.0 diopter (D) or ≥+3.0 D to ≤+6.0 D associated with reduced near visual function (near VA 20/40 or worse; stereoacuity worse than 240")]. Hyperopia with reduced near visual function also was associated with attention deficits. Compared to emmetropic children, VA (distance, near), accommodative accuracy, and stereoacuity were significantly reduced in moderate hyperopes, with the greatest risk in those with higher hyperopia. Increasing hyperopia was associated with decreasing visual function., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2022 Asia-Pacific Academy of Ophthalmology. Published by Wolters Kluwer Health, Inc. on behalf of the Asia-Pacific Academy of Ophthalmology.)

Significance: Technological advancements have made distributing reading materials in audio formats more common. Investigating how presentation mode impacts comprehension among sighted and blind individuals will inform the distribution of information to enhance comprehension., Purpose: The aims were (1) to investigate the hypothesis that reading comprehension is enhanced by increased physical engagement and cognitive effort through text or braille and (2) to explore how assistive technology impacts comprehension for blind individuals., Methods: In a within-subjects design, 31 sighted and 34 blind participants read and listened to scientific passages and verbally answered free-response questions about what they read and heard. For sighted participants, passages were presented in text and human voice actor recordings. For blind participants, passages were presented with hard-copy braille, a refreshable braille display, voice actor recordings, and a screen reader., Results: Comprehension scores were analyzed using mixed-effects regression and pairwise comparisons on the estimated marginal means. In study 1, the comprehension difference between text or hard-copy braille and the voice actor formats was assessed to address the first aim. Sighted participants had better comprehension with text (mean, 74.8%; 95% confidence interval [CI], 70.5 to 79.1%) than with a voice actor (mean, 69.7%; 95% CI, 65.4 to 74.0%; P = .02), and blind participants had superior comprehension with hard-copy braille (mean, 70.4%; 95% CI, 63.3 to 77.5%) than with a voice actor (mean, 61.9%; 95% CI, 54.7 to 69.0%; P = .03). In study 2, the comprehension differences among blind participants between the four formats were investigated to address the second aim. Comprehension was better with hard-copy braille (mean, 70.6%; 95% CI, 63.4 to 77.7%) than with a screen reader (mean, 60.7%; 95% CI, 53.5 to 67.9%; P = .02) and better with a braille display (mean, 69.7%; 95% CI, 62.5 to 76.9%) than with a screen reader (P = .04)., Conclusions: Study 1 supports the hypothesis that more physically engaging tasks enhance comprehension, and study 2 suggests that listening to scientific materials using a synthesized voice may reduce comprehension ability compared with hard-copy braille and braille displays.

Coordination of attention between a social partner and an external focus of shared interest, called joint engagement, is associated with positive developmental outcomes such as better language, socio-emotional, and theory of mind skills in sighted infants. Current measures of joint engagement rely on an infant's visual behaviors, making it difficult to study joint engagement in infants with low or no vision. In a naturalistic observational study, 20 infants with various levels of visual impairments - mean ages: 1.08 years (N=9) and 1.62 years (N=18), were videotaped during 30-min free play sessions with their caregivers. Seven infants were tested at both ages. Videos were coded to determine the percentage of time the dyads participated in joint engagement. Results showed that all visually impaired infants participated in joint engagement, with a significant increase between earlier and later ages. Infants' visual impairment levels were described in terms of visual acuity and contrast sensitivity as measured using both visual evoked potential and preferential looking techniques. Of the visual measurements, infants' reduction in contrast sensitivity measured with preferential looking, alone, predicted the infants' percentage of time in joint engagement across ages. Contrary to prior research that exclusively focused on visual acuity, this finding supports the need to include contrast sensitivity measurements in studies with visually impaired infants., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: To determine demographic and refractive risk factors for astigmatism in the Vision in Preschoolers Study., Methods: Three- to 5-year-old Head Start preschoolers (N = 4040) from five clinical centers underwent comprehensive eye examinations by study-certified optometrists and ophthalmologists, including monocular visual acuity testing, cover testing, and cycloplegic retinoscopy. Astigmatism was defined as the presence of greater than or equal to +1.5 diopters (D) cylinder in either eye, measured with cycloplegic refraction. The associations of risk factors with astigmatism were evaluated using the odds ratio (OR) and its 95% confidence interval (CI) from logistic regression models., Results: Among 4040 Vision in Preschoolers Study participants overrepresenting children with vision disorders, 687 (17%) had astigmatism, and most (83.8%) had with-the-rule astigmatism. In multivariate analyses, African American (OR, 1.65; 95% CI, 1.22 to 2.24), Hispanic (OR, 2.25; 95% CI, 1.62 to 3.12), and Asian (OR, 1.76; 95% CI, 1.06 to 2.93) children were more likely to have astigmatism than non-Hispanic white children, whereas American Indian children were less likely to have astigmatism than Hispanic, African American, and Asian children (p < 0.0001). Refractive error was associated with astigmatism in a nonlinear manner, with an OR of 4.50 (95% CI, 3.00 to 6.76) for myopia (≤-1.0 D in spherical equivalent) and 1.55 (95% CI, 1.29 to 1.86) for hyperopia (≥+2.0 D) when compared with children without refractive error (>-1.0 D, <+2.0 D). There was a trend of an increasing percentage of astigmatism among older children (linear trend p = 0.06). The analysis for risk factors of with-the-rule astigmatism provided similar results., Conclusions: Among Head Start preschoolers, Hispanic, African American, and Asian race as well as myopic and hyperopic refractive error were associated with an increased risk of astigmatism, consistent with findings from the population-based Multi-ethnic Pediatric Eye Disease Study and the Baltimore Pediatric Eye Disease Study. American Indian children had lower risk of astigmatism.

Objective: To evaluate risk factors for unilateral amblyopia and for bilateral amblyopia in the Vision in Preschoolers (VIP) study., Design: Multicenter, cross-sectional study., Participants: Three- to 5-year-old Head Start preschoolers from 5 clinical centers, overrepresenting children with vision disorders., Methods: All children underwent comprehensive eye examinations, including threshold visual acuity (VA), cover testing, and cycloplegic retinoscopy, performed by VIP-certified optometrists and ophthalmologists who were experienced in providing care to children. Monocular threshold VA was tested using a single-surround HOTV letter protocol without correction, and retested with full cycloplegic correction when retest criteria were met. Unilateral amblyopia was defined as an interocular difference in best-corrected VA of 2 lines or more. Bilateral amblyopia was defined as best-corrected VA in each eye worse than 20/50 for 3-year-olds and worse than 20/40 for 4- to 5-year-olds., Main Outcome Measures: Risk of amblyopia was summarized by the odds ratios and their 95% confidence intervals estimated from logistic regression models., Results: In this enriched sample of Head Start children (n = 3869), 296 children (7.7%) had unilateral amblyopia, and 144 children (3.7%) had bilateral amblyopia. Presence of strabismus (P<0.0001) and greater magnitude of significant refractive errors (myopia, hyperopia, astigmatism, and anisometropia; P<0.00001 for each) were associated independently with an increased risk of unilateral amblyopia. Presence of strabismus, hyperopia of 2.0 diopters (D) or more, astigmatism of 1.0 D or more, or anisometropia of 0.5 D or more were present in 91% of children with unilateral amblyopia. Greater magnitude of astigmatism (P<0.0001) and bilateral hyperopia (P<0.0001) were associated independently with increased risk of bilateral amblyopia. Bilateral hyperopia of 3.0 D or more or astigmatism of 1.0 D or more were present in 76% of children with bilateral amblyopia., Conclusions: Strabismus and significant refractive errors were risk factors for unilateral amblyopia. Bilateral astigmatism and bilateral hyperopia were risk factors for bilateral amblyopia. Despite differences in selection of the study population, these results validated the findings from the Multi-Ethnic Pediatric Eye Disease Study and Baltimore Pediatric Eye Disease Study., (Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate associations between stereoacuity and presence, type, and severity of vision disorders in Head Start preschool children and determine testability and levels of stereoacuity by age in children without vision disorders., Methods: Stereoacuity of children aged 3 to 5 years (n = 2898) participating in the Vision in Preschoolers (VIP) Study was evaluated using the Stereo Smile II test during a comprehensive vision examination. This test uses a two-alternative forced-choice paradigm with four stereoacuity levels (480 to 60 seconds of arc). Children were classified by the presence (n = 871) or absence (n = 2027) of VIP Study-targeted vision disorders (amblyopia, strabismus, significant refractive error, or unexplained reduced visual acuity), including type and severity. Median stereoacuity between groups and among severity levels of vision disorders was compared using Wilcoxon rank sum and Kruskal-Wallis tests. Testability and stereoacuity levels were determined for children without VIP Study-targeted disorders overall and by age., Results: Children with VIP Study-targeted vision disorders had significantly worse median stereoacuity than that of children without vision disorders (120 vs. 60 seconds of arc, p < 0.001). Children with the most severe vision disorders had worse stereoacuity than that of children with milder disorders (median 480 vs. 120 seconds of arc, p < 0.001). Among children without vision disorders, testability was 99.6% overall, increasing with age to 100% for 5-year-olds (p = 0.002). Most of the children without vision disorders (88%) had stereoacuity at the two best disparities (60 or 120 seconds of arc); the percentage increasing with age (82% for 3-, 89% for 4-, and 92% for 5-year-olds; p < 0.001)., Conclusions: The presence of any VIP Study-targeted vision disorder was associated with significantly worse stereoacuity in preschool children. Severe vision disorders were more likely associated with poorer stereopsis than milder or no vision disorders. Testability was excellent at all ages. These results support the validity of the Stereo Smile II for assessing random-dot stereoacuity in preschool children.

Objective: To compare the prevalence of amblyopia, strabismus, and significant refractive error among African-American, American Indian, Asian, Hispanic, and non-Hispanic white preschoolers in the Vision In Preschoolers study., Design: Multicenter, cross-sectional study., Participants: Three- to 5-year old preschoolers (n=4040) in Head Start from 5 geographically disparate areas of the United States., Methods: All children who failed the mandatory Head Start screening and a sample of those who passed were enrolled. Study-certified pediatric optometrists and ophthalmologists performed comprehensive eye examinations including monocular distance visual acuity (VA), cover testing, and cycloplegic retinoscopy. Examination results were used to classify vision disorders, including amblyopia, strabismus, significant refractive errors, and unexplained reduced VA. Sampling weights were used to calculate prevalence rates, confidence intervals, and statistical tests for differences., Main Outcome Measures: Prevalence rates in each racial/ethnic group., Results: Overall, 86.5% of children invited to participate were examined, including 2072 African-American, 343 American Indian (323 from Oklahoma), 145 Asian, 796 Hispanic, and 481 non-Hispanic white children. The prevalence of any vision disorder was 21.4% and was similar across groups (P=0.40), ranging from 17.9% (American Indian) to 23.3% (Hispanic). Prevalence of amblyopia was similar among all groups (P=0.07), ranging from 3.0% (Asian) to 5.4% (non-Hispanic white). Prevalence of strabismus also was similar (P=0.12), ranging from 1.0% (Asian) to 4.6% (non-Hispanic white). Prevalence of hyperopia >3.25 diopter (D) varied (P=0.007), with the lowest rate in Asians (5.5%) and highest in non-Hispanic whites (11.9%). Prevalence of anisometropia varied (P=0.009), with the lowest rate in Asians (2.7%) and highest in Hispanics (7.1%). Myopia >2.00 D was relatively uncommon (<2.0%) in all groups with the lowest rate in American Indians (0.2%) and highest rate in Asians (1.9%). Prevalence of astigmatism >1.50 D varied (P=0.01), with the lowest rate among American Indians (4.3%) and highest among Hispanics (11.1%)., Conclusions: Among Head Start preschool children, the prevalence of amblyopia and strabismus was similar among 5 racial/ethnic groups. Prevalence of significant refractive errors, specifically hyperopia, astigmatism, and anisometropia, varied by group, with the highest rate of hyperopia in non-Hispanic whites, and the highest rates of astigmatism and anisometropia in Hispanics., (Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine the intertester agreement of refractive error measurements between lay and nurse screeners using the Retinomax Autorefractor and the SureSight Vision Screener., Methods: Trained lay and nurse screeners measured refractive error in 1452 preschoolers (3 to 5 years old) using the Retinomax and the SureSight in a random order for screeners and instruments. Intertester agreement between lay and nurse screeners was assessed for sphere, cylinder, and spherical equivalent (SE) using the mean difference and the 95% limits of agreement. The mean intertester difference (lay minus nurse) was compared between groups defined based on the child's age, cycloplegic refractive error, and the reading's confidence number using analysis of variance. The limits of agreement were compared between groups using the Brown-Forsythe test. Intereye correlation was accounted for in all analyses., Results: The mean intertester differences (95% limits of agreement) were -0.04 (-1.63, 1.54) diopter (D) sphere, 0.00 (-0.52, 0.51) D cylinder, and -0.04 (1.65, 1.56) D SE for the Retinomax and 0.05 (-1.48, 1.58) D sphere, 0.01 (-0.58, 0.60) D cylinder, and 0.06 (-1.45, 1.57) D SE for the SureSight. For either instrument, the mean intertester differences in sphere and SE did not differ by the child's age, cycloplegic refractive error, or the reading's confidence number. However, for both instruments, the limits of agreement were wider when eyes had significant refractive error or the reading's confidence number was below the manufacturer's recommended value., Conclusions: Among Head Start preschool children, trained lay and nurse screeners agree well in measuring refractive error using the Retinomax or the SureSight. Both instruments had similar intertester agreement in refractive error measurements independent of the child's age. Significant refractive error and a reading with low confidence number were associated with worse intertester agreement.

Purpose: To evaluate the relationship of anisometropia with unilateral amblyopia, interocular acuity difference (IAD), and stereoacuity among Head Start preschoolers using both clinical notation and vector notation analyses., Design: Multicenter, cross-sectional study., Participants: Three- to 5-year-old participants in the Vision in Preschoolers (VIP) study (n = 4040)., Methods: Secondary analysis of VIP data from participants who underwent comprehensive eye examinations, including monocular visual acuity testing, stereoacuity testing, and cycloplegic refraction. Visual acuity was retested with full cycloplegic correction when retest criteria were met. Unilateral amblyopia was defined as IAD of 2 lines or more in logarithm of the minimum angle of resolution (logMAR) units. Anisometropia was defined as a 0.25-diopter (D) or more difference in spherical equivalent (SE) or in cylinder power and 2 approaches using power vector notation. The percentage with unilateral amblyopia, mean IAD, and mean stereoacuity were compared between anisometropic and isometropic children., Main Outcomes Measures: The percentage with unilateral amblyopia, mean IAD, and mean stereoacuity., Results: Compared with isometropic children, anisometropic children had a higher percentage of unilateral amblyopia (8% vs. 2%), larger mean IAD (0.07 vs. 0.05 logMAR), and worse mean stereoacuity (145 vs. 117 arc sec; all P<0.0001). Larger amounts of anisometropia were associated with higher percentages of unilateral amblyopia, larger IAD, and worse stereoacuity (P<0.001 for trend). The percentage of unilateral amblyopia increased significantly with SE anisometropia of more than 0.5 D, cylindrical anisometropia of more than 0.25 D, vertical and horizontal meridian (J0) or oblique meridian (J45) of more than 0.125 D, or vector dioptric distance of more than 0.35 D (all P<0.001). Vector dioptric distance had greater ability to detect unilateral amblyopia than cylinder, SE, J0, or J45 (P<0.001)., Conclusions: The presence and amount of anisometropia were associated with the presence of unilateral amblyopia, larger IAD, and worse stereoacuity. The threshold level of anisometropia at which unilateral amblyopia became significant was lower than current guidelines. Vector dioptric distance is more accurate than spherical equivalent anisometropia or cylindrical anisometropia in identifying preschoolers with unilateral amblyopia., (Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: Cortical visual impairment (CVI) is bilateral visual impairment caused by damage to the posterior visual pathway, the visual cortex, or both. Current literature reports great variability in the prognosis of CVI. The purpose of this study was to evaluate change in vision function in children with CVI over time using a quantitative assessment method., Methods: The visual acuity and contrast sensitivity of children with CVI were retrospectively assessed using the sweep visual evoked potential (VEP). Thirty-nine children participated in the visual acuity assessment and 34 of the 39 children participated in the contrast threshold assessment. At the time of the first VEP, the children ranged in age from 1 to 16 years (mean: 5.0 years). The time between measures ranged from 0.6 to 13.7 years (mean: 6.5 years)., Results: Forty-nine percent of the children studied showed significant improvement of visual acuity. The average improvement was 0.43 log unit (mean change: 20/205 to 20/76) in those who improved. The initial visual acuity was worse in those who improved compared with those who did not improve (p < 0.001). Forty-seven percent of the children studied showed significant improvement of contrast threshold. In those who improved, the average amount of improvement was 0.57 log unit (10 to 2.6% Michelson). The initial contrast threshold was significantly worse in those who improved compared with those who did not improve (p = 0.001). Also, the change in contrast threshold was related to age of the child (p = 0.017)., Conclusions: Significant improvement in vision function can occur over time in children with CVI. In the present study, approximately 50% of the children improved and the remainder remained stable. No relation was found between etiology and improvement. Further investigation is warranted to better understand the prognosis for visual recovery in children with CVI.

Purpose: To compare 11 preschool vision screening tests administered by licensed eye care professionals (LEPs; optometrists and pediatric ophthalmologists)., Design: Multicenter, cross-sectional study., Participants: A sample (N = 2588) of 3- to 5-year-old children enrolled in Head Start was selected to over-represent children with vision problems., Methods: Certified LEPs administered 11 commonly used or commercially available screening tests. Results from a standardized comprehensive eye examination were used to classify children with respect to 4 targeted conditions: amblyopia, strabismus, significant refractive error, and unexplained reduced visual acuity (VA)., Main Outcome Measures: Sensitivity for detecting children with > or =1 targeted conditions at selected levels of specificity was the primary outcome measure. Sensitivity also was calculated for detecting conditions grouped into 3 levels of importance., Results: At 90% specificity, sensitivities of noncycloplegic retinoscopy (NCR) (64%), the Retinomax Autorefractor (63%), SureSight Vision Screener (63%), and Lea Symbols test (61%) were similar. Sensitivities of the Power Refractor II (54%) and HOTV VA test (54%) were similar to each other. Sensitivities of the Random Dot E stereoacuity (42%) and Stereo Smile II (44%) tests were similar to each other and lower (P<0.0001) than the sensitivities of NCR, the 2 autorefractors, and the Lea Symbols test. The cover-uncover test had very low sensitivity (16%) but very high specificity (98%). Sensitivity for conditions considered the most important to detect was 80% to 90% for the 2 autorefractors and NCR. Central interpretations for the MTI and iScreen photoscreeners each yielded 94% specificity and 37% sensitivity. At 94% specificity, the sensitivities were significantly better for NCR, the 2 autorefractors, and the Lea Symbols VA test than for the 2 photoscreeners for detecting > or =1 targeted conditions and for detecting the most important conditions., Conclusions: Screening tests administered by LEPs vary widely in performance. With 90% specificity, the best tests detected only two thirds of children having > or =1 targeted conditions, but nearly 90% of children with the most important conditions. The 2 tests that use static photorefractive technology were less accurate than 3 tests that assess refractive error in other ways. These results have important implications for screening preschool-aged children.

Purpose: To compare visual acuity results obtained using the Lea Symbols chart with visual acuity results obtained with the Bailey-Lovie chart in school-aged children and adults using a within-subjects comparison of monocular acuity results., Methods: Subjects were 62 individuals between 4.5 and 60 years of age, recruited from patients seen in five optometry clinics. Each subject had acuity of the right eye and the left eye tested with the Lea Symbols chart and the Bailey-Lovie chart, with order of testing varied across subjects. Outcome measures were monocular logarithm of the minimum angle of resolution (logMAR) visual acuity and inter-eye acuity difference in logMAR units for each test., Results: Correlation between acuity results obtained with the two charts was high. There was no difference in absolute inter-eye acuity difference measured with the two acuity charts. However, on average, Lea Symbols acuity scores were one logMAR line better than Bailey-Lovie acuity scores, and this difference increased with worse visual acuity., Conclusions: The Lea Symbols chart provides a measure of inter-eye difference that is similar to that obtained with the Bailey-Lovie chart. However, the monocular acuity results obtained with the Lea Symbols chart differ from those obtained with the Bailey-Lovie chart, and the difference is dependent on the individual's absolute level of visual acuity.

A state-by-state survey regarding preschool vision screening guidelines, policies, and procedures was conducted. Currently 34 states provide vision screening guidelines and 15 states require vision screening of at least some of their preschool-aged children. The Department of Public Health administers the programs in 26 states, the Department of Education in 13. A wide range of professional and lay personnel conduct preschool vision screenings, and nurses participate in the screening process in 22 states. Visual acuity is assessed in 30 states, eye alignment in 24 states, refractive error in eight states, and color vision in 10 states. A combination of screening tests is recommended in 24 states. Currently, 45 states do not require screening of all preschool children. Thus, although laws, guidelines, and recommendations exist in most states, many preschool-age children do not have access to vision screening programs.

Monocular oscillatory-motion visual evoked potentials (VEPs) were measured in prospective and retrospective groups of infantile esotropia patients who had been aligned surgically at different ages. A nasalward-temporal response bias that is present prior to surgery was reduced below pre-surgery levels in the prospective group. Patients in the retrospective group who had been aligned before 2 yr of age showed lower levels of response asymmetry than those who were aligned after age 2. The data imply that binocular motion processing mechanisms in infantile esotropia patients are capable of some degree of recovery, and that this plasticity is restricted to a critical period of visual development.

Visual evoked potentials (VEPs) were recorded monocularly in response to vertical gratings that underwent oscillatory apparent motion at a temporal frequency of 10 Hz. In normal infants 6 months or younger and in patients with a history of constant strabismus onset before 6 months of age, the oscillatory motion VEP contains a prominent first harmonic component that is temporally 180 degrees out of phase in the two eyes. This pattern is not seen in normal adults and is consistent with the presence of a nasalward/temporalward asymmetry of cortical responsiveness in infants and in patients with early onset strabismus.

Monocular and binocular grating acuities were measured using a swept spatial frequency visual evoked potential (VEP) technique in a group of fifteen infants with esotropia and alternating fixation. Both monocular and binocular acuity measures fell significantly below the mean for age-matched normals. Infants with esotropia and alternating fixation did not have significant interocular acuity differences.