Non‐cycloplegic video‐refraction and cycloplegic retinoscopy refraction results are reported for a Cambridge population of binocular, non‐strabismic infants aged 7–9 months.Method: The Cambridge vision screening programme detected high refractive errors by measuring the accommodative response to a 75 cm distance toy using the VPR‐1 video‐refractor. Of 4452 infants screened, the binocular mean refraction was −0.7 D, i.e. +0.62 D accommodative ‘lag’ or focus error (SD = ± 0.92 D). Seven percent had + 1.5 D refraction, i.e. + 2.8 D focus error or accommodative ‘lag’ in any one meridian. Of those followed up, refraction was also measured by cycloplegic retinoscopy (cycloRet) and VPR‐1 (cyclo VPR) after 1 drop 1% cyclopentolate.Results: Of the 223 infants who had large lags of accommodation + 2.8 D: (a) High hyperopia of + 3.5 D in any one meridian, by cyclo‐Ret, was found in 173/223 (78%) of these infants. The mean cyclo‐Ret spherical equivalent was + 3.8 ± 1.8 DS and unsigned astigmatism 0.8 ± 0.7 DC. The magnitude of the largest accommodative lag was significantly related to the cyclo‐Ret most‐positive‐meridional power (r = 0.4, P < 0.0001, n = 223). The majority orientation of the largest (non‐cyclo‐VPR) lag power was horizontal (WTR astigmatism). (b) The latest longitudinal refractive changes in this highly hyperopic group and also a control group will be described in terms of mean spherical equivalent, astigmatism and anisometropia.Conclusion: The large lags of accommodation can reveal infants with highly hyperopic meridians. These infants may require early partial spectacle correction.Acknowledgement: Supported by the Medical Research Council (Grant G7908507).

OBJECTIVES:To compare the age of onset of the pattern orientation reversal visual evoked potential (OR-VEP) in a group of very low birthweight (VLBW) premature infants with term infants matched for postconceptual age at testing. The OR-VEP measure is used as an indicator of visual cortical functioning because of the specificity of cortical neurones in showing sensitivity to changes of slant or orientation. DESIGN:Results are given for 24 VLBW infants, born at 24-32 weeks gestation weighing less than 1500 g, and 31 infants born at term. The steady state evoked potential to a grating pattern reversing in orientation (between 45 degrees and 135 degrees) at 4 reversals/second and 8 reversals/second was recorded. RESULTS:The VLBW infants with normal neonatal ultrasound results (and normal neurological outcome at 3 years of age) showed a significant OR-VEP with a similar postnatal time course to the term infants. Four premature infants, showing appreciable abnormalities on ultrasound examination, did not show normal onset of the OR-VEP, and all had an abnormal neurological outcome. CONCLUSIONS:This result can be taken to indicate that the onset of cortical function is similar in healthy preterm infants to term infants. The visual development of the premature infants was neither accelerated nor delayed as a result of their extra visual experience. The OR-VEP can be used as a prognostic indicator of early brain development alongside other neurological measures. It may also be a very early indicator of later neurological outcome.

Aim: The Cambridge vision screening programme allows the emmetropization process to be described in a large infant population (n = 278 infants). Cycloplegic retinoscopy refraction change between 9 and 20 months of age is described for various refractive components.Methods: Following videorefractive VPR‐1 screening at 75 cm, of over 5000 infants, groups of infants with large lags (>2.8 D) and normal lags (<2.8 D) of accommodation were longitudinally followed‐up. All were non‐strabismic. 1% cyclopentolate retinoscopy results (sphero‐cyl lens neutralized ± 0.5 D) were analysed.Results: For all components, the emmetropization rate significantly correlated with the initial powers (difference v mean correlation R).The relationship of hyperopia and astigmatism reduction will be discussed. Emmetropization in a subgroup of infants wearing spectacles will also be presented.Conclusion: Analysis of infant emmetropization shows the refractive components emmetropize with their rate of reduction related to initial power.Acknowledgement: Supported by Medical Research Council Grant G7908507.

Rapid emmetropization is described in pediatrically normal infants from 9 months of age during the following year. The infants, obtained from various categories of the Cambridge population screening program, provided a broad range of refractive errors. The large group of 254 nonanisometropic infants studied allowed the mean rate of change and dependence on the initial refraction value to be determined. Refraction was measured by cycloplegic retinoscopy. Rapid emmetropization changes occurred in the following refractive components: mean spherical equivalent (MSE), astigmatism magnitude, the horizontal astigmatism component, the infant's most positive meridian, and the infant's most negative meridian. The MSE and astigmatism rates of change (diopters/year), were highly dependent on their respective initial powers (r = -0.61 and r = -0.76). The percentage weighted mean proportional rate of change for MSE was -30% (SE 4%) and for astigmatism magnitude it was -59% (SE 14%). There was much individual variation, with some exhibiting fast emmetropization and others not. The MSE and astigmatism changes, however, were almost independent of each other. The refractive errors of the most positive and most negative meridians emmetropize because they are both derived from the MSE and half the astigmatism. With-the-rule astigmatism was more prevalent than against-the-rule astigmatism at 9 months of age, and with-the-rule astigmatism exhibited a significantly greater proportional rate of change. The relationship of emmetropization and refractive screening is considered. A new component "MOMS" is introduced, the maximum ocular meridional separation, when both eyes are considered. Thus incorporating astigmatism and anisometropia may be a good single indicator of conditions associated with later amblyopia. The almost independent emmetropization of the MSE and astigmatism components is an important result to consider in theories of emmetropization, refractive screening, clinical prescribing, and the evaluation of infants in treatment trials.