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The manifest refractions of 37 high myopic and 16 high hypermetropic eyes in a total of 28 patients, aged 5 to 42 years, were determined on the Nikon NR-1000F Auto Refractometer. The data obtained were compared with the final clinical prescriptions for these eyes and analysed for degree of agreement for the spherical equivalents, sphere components, and cylinder powers and axes. The Auto Refractometer recordings for all the different refractive components were observed to skew towards more minus in the high myopic eyes but more plus in the high hypermetropes. The possible significance of these skewing patterns is discussed with reference to our earlier studies.

A procedure is described for the ophthalmoscopic examination of the fundus in children after 1% or 2% oral fluorescein ingestion without sedation or anaesthesia. No major complications or any allergic reactions were observed. In the ophthalmoscopically normal fundi of the five healthy children studied the fluorescence of the nerve head and retinal blood vessels could be visualised at 15 minutes, increasing at 30 minutes, and declining by 60 minutes. The possible problems of the technique are discussed.

Nine eyes of suspected papilloedema, 21 with incipient papilloedema, and 16 with pseudopapilloedema in 23 children aged 1 month to 10 years were examined after oral fluorescein. In pseudopapilloedema the retinal vascular fluorescence and slight disc head fluorescence with sharp margins at 30 minutes markedly declined by 60 minutes. These features were similar to our earlier findings with oral fluorescein in the normal fundi of children. Of the 30 eyes with suspected or incipient papilloedema late disc and peripapillary 'staining', polar or diffuse was observed in 12, the 60 minutes fluorescence being more than at 30 minutes in nine and of equal in intensity in three. In these 12 'positive' eyes, and four more of the 18 'negative' eyes, the retinal vascular fluorescence at 60 minutes was significantly more than at 30 minutes. The problems of interpretation after oral fluorescein in the early diagnosis of papilloedema in children and the possible fallacies are discussed.

The manifest (dry) refractions of 165 eyes of 86 patients, aged 6 to 75 years, were studied on the Nikon Auto Refractometer NR-1000F. The results obtained were compared with the clinical refractive data, and they were analysed for degree of agreement of various refractive components in different types and grades of refractive errors in the separate age groups. On the NR-1000F the spherical and cylindrical components and spherical equivalents skewed towards more minus (or less plus), especially so in emmetropes, low hypermetropes, and low myopes. This error declined with increasing age over 40 years and was also significantly lower in aphakia and mixed astigmatism. Determination of cylinder axis was found to be reliable on the NR-1000F. In spite of the obvious utility of the device its inbuilt automatic fogging system does not seem adequately to neutralise the patient's accommodative efforts, as the fixation target probably induces instrument myopia.

The manifest (dry) and cycloplegic refractions of 50 eyes of 25 patients aged 8 to 28 years were studied on the Nikon Auto Refractometer NR-1000F (AR) and compared with the results of clinical refraction (CR) under homatropine and the final clinical acceptance on postmydriatic testing. Only patients in the younger age groups with low to moderate refractive errors were included in this study; high myopes and hypermetropes and patients with aphakia and mixed astigmatism were excluded. The degree of agreement for spherical equivalents, sphere components, and cylinder components was analysed separately for both cycloplegic and manifest refractions on the AR and CR. The results showed that the fixation target in the NR-1000F induces significant instrument myopia during manifest refraction in the younger patients with lower refractive errors. We recommend that caution should be exercised in interpreting manifest refractions on the AR, especially in younger patients. A cycloplegic automatic refraction would be acceptably accurate.