The prevalence of myopia among the Chinese schoolchildren population in Hong Kong as observed in this cross-sectional study are similar to our previously reported findings from almost two decades ago. There is no evidence that prevalence of myopia is increasing with time over the last two decades. However, the prevalence and degree of myopia in Chinese children is high as compared with other ethnic groups such as those reported among Caucasians.

Peripheral retinal degenerative changes and optic nerve crescent were found in a significant proportion of high myopic teenage subjects. There is increased risk of retinal changes in eyes with an axial length >26.5 mm in 12-18 year-olds.

There was general reduction in retinal thickness within the horizontal central 80° in myopic eyes compared with non-myopic eyes.

Background:Optomap uses the ultra-wide field scanning laser ophthalmoscopy to provide retinal examination. It permits fundus examination without the use of a mydriatic, which is more comfortable for the patients. This paper determines the sensitivity and specificity of the Optomap for detecting retinal signs under non-mydriatic conditions. Methods: Fifty-four eyes identified with retinal/choroidal signs and eight normal eyes were recruited from 31 Hong Kong Chinese subjects. Photo-documentation of fundal changes was obtained with the Optomap under non-mydriatic conditions before a dilated fundus examination by a clinician using standard procedures. The eyelid was retracted using a cotton bud when necessary. Dilated fundus examinations were performed by another clinician using binocular indirect ophthalmoscopy and slitlamp biomicroscopy with a fundus lens. The Optomap images were evaluated by four other investigators under masked condition. The International Classification of Disease, Ninth Revision (ICD-9-CM) was adopted for recording retinal features. Screening results were compared with those obtained using the dilated fundus examination as the gold standard. Results: The cotton bud method for eyelid retraction showed an improvement in the area of retina that could be visualised. The sensitivity and specificity of the Optomap averaged 76.4 and 71.9 per cent, respectively. Some fundal signs were missed by all observers in the Optomap but not with the biomicroscope. These included white-without-pressure, lattice degeneration, paramacular drusen and pigmentary changes at central fundus. Conclusion: Optomap serves as a reliable screening tool for fundus examination especially because it covers a much wider area of the peripheral retina than other digital instruments for fundus photography.