School bus accommodation-relaxing skiascopy

OBJECTIVE: Accurate estimation of hyperopia and astigmatism is challenging in delayed children. Conventional skiascopy holds rows of increasing power ± lenses vertically in front of one eye. The school bus accommodation-relaxing skiascopy (SBA-RS) design holds child-friendly, lenses +1 to +10D horizontally so that a higher power fogs the nontested eye-relaxing accommodation without cycloplegia. METHODS: Design: Evaluation of diagnostic test. Subjects: Patients undergoing comprehensive eye examination in a pediatric ophthalmology practice. Cycloplegic (cyclopentolate 1%) retinoscopy was compared to dry SBA-RS and Retinomax (Righton, Japan) during pediatric eye examinations. Outcome measures: correlations, Chi-square and receiver operating characteristic (ROC) curve. RESULTS: Of 470 patients with a median age 6 years, 238 were under the age of 60 months and 110 had developmental delays. For those with cycloplegic spherical equivalent hyperopia over 0.7 D, median (90% CI) value for retinoscopy was +2.63 D (+0.75, +6.88), for SBA-RS was +2.50 D (+0.50, +6.75) and less for 184 with Retinomax +1.88 D (−1.56, +6.13) but similar despite delays. Astigmatic cylinder SBA-RS +1.50 D (+0.25, +4.00) lagged retinoscopy +1.75 D (+0.75,+4.50) but Retinomax was greater +2.00 D (+0.25, +4.64). Cycloplegic refractive components such as spherical equivalent, cylinder, and J0 and J45 power vectors correlated highly and were near unity with SBA-RS and Retinomax with the latter deviating greater. SBA-RS screened for amblyopia risk factors up to 92% sensitive and 94% specific. CONCLUSION: Accommodation-relaxing horizontal skiascopy very precisely estimates astigmatism power and axis and only lags cycloplegic refraction by about 0.15D in hyperopic patients fairly independent of neurodevelopmental delay. This technique can quickly estimate refraction even in delayed patients potentially reducing some need for cycloplegia. CLINICAL TRIALS REGISTRY: NCT03668067.