Josephine Ibironke

Prevalence of Amblyopia and Strabismus in White and African-American Children Aged 6 through 71 Months: The Baltimore Pediatric Eye Disease Study

OBJECTIVE To determine the age-specific prevalence of strabismus in white and African American children aged 6 through 71 months and of amblyopia in white and African American children aged 30 through 71 months. DESIGN Cross-sectional, population-based study. PARTICIPANTS White and African American children aged 6 through 71 months in Baltimore, MD, United States. Among 4132 children identified, 3990 eligible children (97%) were enrolled and 2546 children (62%) were examined. METHODS Parents or guardians of eligible participants underwent an in-home interview and were scheduled for a detailed eye examination, including optotype visual acuity and measurement of ocular deviations. Strabismus was defined as a heterotropia at near or distance fixation. Amblyopia was assessed in those children aged 30 through 71 months who were able to perform optotype testing at 3 meters. MAIN OUTCOME MEASURES The proportions of children aged 6 through 71 months with strabismus and of children aged 30 through 71 months with amblyopia. RESULTS Manifest strabismus was found in 3.3% of white and 2.1% of African American children (relative prevalence [RP], 1.61; 95% confidence interval [CI], 0.97-2.66). Esotropia and exotropia each accounted for close to half of all strabismus in both groups. Only 1 case of strabismus was found among 84 white children 6 through 11 months of age. Rates were higher in children 60 through 71 months of age (5.8% for whites and 2.9% for African Americans [RP, 2.05; 95% CI, 0.79-5.27]). Amblyopia was present in 12 (1.8%) white and 7 (0.8%) African American children (RP, 2.23; 95% CI, 0.88-5.62). Only 1 child had bilateral amblyopia. CONCLUSIONS Manifest strabismus affected 1 in 30 white and 1 in 47 African American preschool-aged children. The prevalence of amblyopia was <2% in both whites and African Americans. National population projections suggest that there are approximately 677,000 cases of manifest strabismus among children 6 through 71 months of age and 271 000 cases of amblyopia among children 30 through 71 months of age in the United States.

Prevalence of refractive error among preschool children in an urban population: the Baltimore Pediatric Eye Disease Study.

PURPOSE To determine the age-specific prevalence of refractive errors in white and African-American preschool children. DESIGN The Baltimore Pediatric Eye Disease Study is a population-based evaluation of the prevalence of ocular disorders in children aged 6 to 71 months in Baltimore, Maryland. PARTICIPANTS Among 4132 children identified, 3990 eligible children (97%) were enrolled and 2546 children (62%) were examined. METHODS Cycloplegic autorefraction was attempted in all children with the use of a Nikon Retinomax K-Plus 2 (Nikon Corporation, Tokyo, Japan). If a reliable autorefraction could not be obtained after 3 attempts, cycloplegic streak retinoscopy was performed. MAIN OUTCOME MEASURES Mean spherical equivalent (SE) refractive error, astigmatism, and prevalence of higher refractive errors among African-American and white children. RESULTS The mean SE of right eyes was +1.49 diopters (D) (standard deviation [SD] = 1.23) in white children and +0.71 D (SD = 1.35) in African-American children (mean difference of 0.78 D; 95% confidence interval [CI], 0.67-0.89). Mean SE refractive error did not decline with age in either group. The prevalence of myopia of 1.00 D or more in the eye with the lesser refractive error was 0.7% in white children and 5.5% in African-American children (relative risk [RR], 8.01; 95% CI, 3.70-17.35). The prevalence of hyperopia of +3 D or more in the eye with the lesser refractive error was 8.9% in white children and 4.4% in African-American children (RR, 0.49; 95% CI, 0.35-0.68). The prevalence of emmetropia (<-1.00 D to <+1.00 D) was 35.6% in white children and 58.0% in African-American children (RR, 1.64; 95% CI, 1.49-1.80). On the basis of published prescribing guidelines, 5.1% of the children would have benefited from spectacle correction. However, only 1.3% had been prescribed correction. CONCLUSIONS Significant refractive errors are uncommon in this population of urban preschool children. There was no evidence for a myopic shift over this age range in this cross-sectional study. A small proportion of preschool children would likely benefit from refractive correction, but few have had this prescribed.

Risk Factors Associated with Childhood Strabismus: The Multi-Ethnic Pediatric Eye Disease and Baltimore Pediatric Eye Disease Studies

OBJECTIVE To investigate risk factors associated with esotropia or exotropia in infants and young children. DESIGN Population-based cross-sectional prevalence study. PARTICIPANTS Population-based samples of 9970 children 6 to 72 months of age from California and Maryland. METHODS Participants were preschool African-American, Hispanic, and non-Hispanic white children participating in the Multi-Ethnic Pediatric Eye Disease Study and the Baltimore Eye Disease Study. Data were obtained by parental interview and ocular examination. Odd ratios and 95% confidence intervals were calculated to evaluate the association of demographic, behavioral, and clinical risk factors with esotropia and exotropia. MAIN OUTCOME MEASURES Odds ratios (ORs) for various risk factors associated with esotropia or exotropia diagnosis based on cover testing. RESULTS In multivariate logistic regression analysis, esotropia was associated independently with prematurity, maternal smoking during pregnancy, older preschool age (48-72 months), anisometropia, and hyperopia. There was a severity-dependent association of hyperopia with the prevalence of esotropia, with ORs increasing from 6.4 for 2.00 diopters (D) to less than 3.00 D of hyperopia, to 122.0 for 5.00 D or more of hyperopia. Exotropia was associated with prematurity, maternal smoking during pregnancy, family history of strabismus, female sex, astigmatism (OR, 2.5 for 1.50 to <2.50 D of astigmatism, and 5.9 for ≥2.5 D of astigmatism), and anisoastigmatism in the J0 component (OR, ≥2 for J0 anisoastigmatism of ≥0.25 D). CONCLUSIONS Prematurity and maternal smoking during pregnancy are associated with a higher risk of having esotropia and exotropia. Refractive error is associated in a severity-dependent manner to the prevalence of esotropia and exotropia. Because refractive error is correctable, these risk associations should be considered when developing guidelines for the screening and management of refractive error in infants and young children. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Prevalence of decreased visual acuity among preschool-aged children in an American urban population: the Baltimore Pediatric Eye Disease Study, methods, and results.

OBJECTIVE To determine the age- and ethnicity-specific prevalence of decreased visual acuity (VA) in white and black preschool-aged children. DESIGN Cross-sectional study. PARTICIPANTS The Baltimore Pediatric Eye Disease Study is a population-based evaluation of the prevalence of ocular disorders in children 6 through 71 months of age in Baltimore, Maryland, United States. Among 4132 children identified, 3990 eligible children (97%) were enrolled and 2546 children (62%) were examined. This report focuses on 1714 of 2546 examined children (67%) who were 30 through 71 months of age. METHODS Field staff identified 63 737 occupied dwelling units in 54 census tracts. Parents or guardians of eligible participants underwent an in-home interview, and eligible children underwent a comprehensive eye examination including optotype visual acuity (VA) testing in children 30 months of age and older, with protocol-specified retesting of children with VA worse than an age-appropriate standard. MAIN OUTCOME MEASURES The proportion of children 30 through 71 months of age testable for VA and the proportion with decreased VA as defined by preset criteria. RESULTS Visual acuity was testable in 1504 of 1714 children (87.7%) 30 through 71 months of age. It was decreased at the initial test (wearing glasses if brought to the clinic) in both eyes of 7 of 577 white children (1.21%; 95% confidence interval [CI], 0.49-2.50) and 13 of 725 black children (1.79%; 95% CI, 0.95-3.08), a difference that is not statistically significant. Decreased VA in both eyes after retesting was found in 3 of 598 white children (0.50%; 95% CI, 0.10-1.48) and in 8 of 757 black children (1.06%, 95% CI = 0.45, 2.10), also not statistically significantly different. Uncorrected ametropia explained the decreased VA on initial testing in 10 of the 20 children. CONCLUSIONS Decreased VA in both eyes of children 30 through 71 months of age at presentation in urban Baltimore was 1.2% among white children and 1.8% among black children. After retesting within 60 days of the initial examination and with children wearing best refractive correction, the rate of decreased VA in both eyes was 0.5% among white children and 1.1% among black children.

Risk Factors for Hyperopia and Myopia in Preschool Children: The Multi-Ethnic Pediatric Eye Disease and Baltimore Pediatric Eye Disease Studies

PURPOSE To describe the risk factors associated with hyperopia and myopia among children 6 to 72 months of age. DESIGN Population-based cross-sectional study. PARTICIPANTS Population-based samples of 9970 children 6 to 72 months of age from Los Angeles County, California, and Baltimore, Maryland. METHODS Participants were preschool African-American, Hispanic, and non-Hispanic white children (n = 9770) from Los Angeles, California, and Baltimore, Maryland. Parental questionnaires and a comprehensive eye examination were administered. Demographic, behavioral, and clinical risk factors associated with hyperopia (≥2.00 diopters [D]) and myopia (≤-1.00 D) were determined. MAIN OUTCOME MEASURES Odds ratios (ORs) for risk factors associated with myopia and hyperopia. RESULTS Compared with non-Hispanic whites, African-American (OR, 6.0) and Hispanic (OR, 3.2) children were more likely to be myopic. Children 6 to 35 months of age were more likely to be myopic compared with those 60 to 72 months of age (OR, ≥1.7). Compared with African-American children, non-Hispanic white (OR, 1.63) and Hispanic (OR, 1.49) children were more likely to be hyperopic. Children whose parents had health insurance (OR, 1.5) and those with a history of maternal smoking during pregnancy (OR, 1.4) were more likely to have hyperopia. Astigmatism of 1.5 D or more at any axis was associated with myopia (OR, 4.37) and hyperopia (OR, 1.43). CONCLUSIONS Children in specific racial or ethnic groups and age groups are at higher risk of having myopia and hyperopia. Cessation of maternal smoking during pregnancy may reduce the risk of hyperopia in these children. Given that both myopia and hyperopia are risk factors for the development of amblyopia and strabismus, these risk factors should be considered when developing guidelines for screening and intervention in preschool children. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Risk Factors for Decreased Visual Acuity in Preschool Children: The Multi-Ethnic Pediatric Eye Disease and Baltimore Pediatric Eye Disease Studies

OBJECTIVE To investigate risk factors associated with unilateral or bilateral decreased visual acuity (VA) in preschool children. DESIGN Population-based, cross-sectional prevalence study. PARTICIPANTS Population-based samples of 6504 children ages 30 to 72 months from California and Maryland. METHODS Participants were preschool African-American, Hispanic, and non-Hispanic white children from Los Angeles, California, and Baltimore, Maryland. Data were obtained by a parental interview and a detailed ocular examination. Logistic regression models were used to evaluate the independent associations between demographic, behavioral, and clinical risk factors with unilateral and bilateral decreased VA. MAIN OUTCOME MEASURES Odds ratios (ORs) for various risk factors associated with interocular difference (IOD) in VA of ≥2 lines with ≤20/32 in the worse eye, or bilateral decreased VA <20/40 or <20/50 if <48 months of age. RESULTS In multivariate logistic regression analysis, 2-line IOD with a VA of ≤20/32 was independently associated with Hispanic ethnicity (OR, 2.05), esotropia (OR, 8.98), spherical equivalent (SE) anisometropia (ORs ranging between 1.5 and 39.7 for SE anisometropia ranging between 0.50 to <1.00 diopters [D] and ≥2.00 D), and aniso-astigmatism in J0 or J45 (ORs ranging between 1.4 and ≥5.3 for J0 or J45 differences ranging between 0.25 to <0.50 D and ≥1.00 D). Bilateral decreased VA was independently associated with lack of health insurance (OR, 2.9), lower primary caregiver education (OR, 1.7), astigmatism (OR, 2.3 and 17.6 for astigmatism 1.00 to <2.00 D and ≥2.00 D), and SE hyperopia ≥4.00 D (OR, 10.8). CONCLUSIONS Anisometropia and esotropia are risk factors for IOD in VA. Astigmatism and high hyperopia are risk factors for bilateral decreased VA. Guidelines for the screening and management of decreased VA in preschool children should be considered in light of these risk associations. FINANCIAL DISCLOSURE(S) The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Lack of Concordance between Fixation Preference and HOTV Optotype Visual Acuity in Preschool Children: the Baltimore Pediatric Eye Disease Study

OBJECTIVE To compare the results of fixation preference testing and standardized visual acuity testing in white and black children aged 30 through 71 months. DESIGN Cross-sectional study. PARTICIPANTS The Baltimore Pediatric Eye Disease Study is a population-based evaluation of the prevalence of vision disorders in children aged 6 through 71 months in Baltimore, Maryland, United States. A total 1714 children 30 through 71 months of age were eligible for inclusion in this report, with 1435 (83.7%) testable by both fixation preference and Amblyopia Treatment Study (ATS) visual acuity testing protocol. METHODS The vision of all children 30 through 71 months of age was tested using both the ATS visual acuity testing protocol (using single HOTV symbols with surround bars) and fixation preference testing (FPT). MAIN OUTCOME MEASURES The ability of fixation preference testing to identify children with clinically important interocular differences (IOD) in visual acuity (i.e., two or more logarithm of minimum angle of resolution units of difference or more). RESULTS Fifty-three children had 2 or more lines of IOD in visual acuity. Seven of them were graded as having momentary or no fixation (sensitivity = 13.2%; 95% confidence interval [CI], 5.3-27.2]), whereas 45 were graded as normal by FPT. In all 7 of the cases of poor FPT, the better-seeing eye was preferred. Low sensitivity and high specificity for detecting an IOD of 2 lines or more with FPT were seen for both white (33.3% sensitivity; 95% CI, 9.5-57.2; 99.6% specificity; 95% CI, 98.7-100) and black (6.5% sensitivity; 95% CI, 0.6, 23.2; 99.3% specificity; 95% CI, 98.3-99.8) children. When assessing FPT performance for 3 or more lines of IOD, only 5 of the 20 children (sensitivity, 25%; 95% CI, 6.0-44.0) had FPT grades of momentary or no fixation. CONCLUSIONS Fixation preference testing, when used as part of a population-based research project, does not identify accurately preschool children with 2 lines or more of IOD in presenting visual acuity. The clinical value of this test is poor and its use for diagnosis and monitoring interventions should be reconsidered.

Risk Factors for Astigmatism in Preschool Children: The Multi-Ethnic Pediatric Eye Disease and Baltimore Pediatric Eye Disease Studies

OBJECTIVE To evaluate risk factors for astigmatism in a population-based sample of preschool children. DESIGN Population-based cross-sectional study. PARTICIPANTS Population-based samples of 9970 children ages 6 to 72 months from Los Angeles County, California, and Baltimore, Maryland. METHODS A cross-sectional study of children participating in the Multiethnic Pediatric Eye Disease Study and the Baltimore Eye Disease Study was completed. Data were obtained by clinical examination or by in-person interview. Odds ratios and 95% confidence intervals (CI) were calculated to evaluate potential associations between clinical, behavioral, or demographic factors and astigmatism. MAIN OUTCOME MEASURES Odds ratios (ORs) for various risk factors associated with astigmatism. RESULTS Participants with myopia (≤-1.0 diopters) were 4.6 times as likely to have astigmatism (95% CI, 3.56-5.96) than those without refractive error, whereas participants with hyperopia (≥+2.00 diopters) were 1.6 times as likely (95% CI, 1.39-1.94). Children 6 to <12 months of age were approximately 3 times as likely to have astigmatism than children 5 to 6 years of age (95% CI, 2.28-3.73). Both Hispanic (OR, 2.38) and African-American (OR, 1.47) children were as likely to have astigmatism than non-Hispanic white children. Furthermore, children whose mothers smoked during pregnancy were 1.46 times (95% CI, 1.14-1.87) as likely to have astigmatism than children whose mothers did not smoke. CONCLUSIONS In addition to infancy, Hispanic and African-American race/ethnicity and correctable/modifiable risk factors such as myopia, hyperopia, and maternal smoking during pregnancy are associated with a higher risk of having astigmatism. Although the prevalence of smoking during pregnancy is typically low, this association may suggest etiologic pathways for future investigation. FINANCIAL DISCLOSURE(S) The authors have no proprietary or commercial interest in any of the materials discussed in this article.

The prevalence of ocular structural disorders and nystagmus among preschool-aged children

PURPOSE To describe the prevalence of structural disorders of the eye and nystagmus in preschool-aged children. METHODS Population-based evaluation of children 6 months through 71 months of age in Baltimore, Maryland, United States. RESULTS Among 4,132 children identified from 54 census tracts, 3,990 eligible children (97%) were enrolled and 2,546 children (62%) were examined. Structural disorders were found in 41 children and nystagmus in 9 children for an overall prevalence of 1.96% (95% CI, 1.46%-2.59%). Only 11 (0.43%; 95% CI, 0.22%-0.77%) had vision loss in at least one eye, most often due to posterior segment disease. CONCLUSIONS Structural ocular abnormalities and nystagmus combined are present in nearly 2% of preschool-aged children in this population-based study. Vision loss due to these abnormalities is uncommon.

Microtropia: clinical findings and management for the primary eye care practitioner.

BACKGROUND Microtropia is a small-angle strabismus with a highly developed degree of binocular cooperation. It is a unilateral comitant horizontal deviation less than 5 prism diopters (PD) in the presence of anomalous retinal correspondence (ARC), amblyopia, some motor fusion, and reduced stereoacuity. CASE REPORT A 7-year-old white girl presented for a second opinion concerning unexplained vision loss in the left eye. Visual acuities were 20/20 in the right eye and 20/200 in the left eye. Ocular evaluation found normal eye health with a 4-PD constant left esotropia at near and a 3-PD constant left esotropia at distance on unilateral cover test. A diagnosis of steady nasal eccentric fixation microtropia without identity with strabismic amblyopia in the left eye was made. Over the follow-up period, visual acuity improved but the alignment did not. CONCLUSION Microtropia can defy detection, resulting in a reduced chance of achieving near-normal visual potential in children. It is important for clinicians to understand the possible etiologies, related entities, proper testing, differential diagnoses, and the goals of treatment. This case report reviews the clinical findings, diagnoses, and management of patients with microtropia.