Prof. Carly LAM and Prof. Chi-ho TO from the School of Optometry have invented a new way to retard myopia progression for children by working on the natural homeostatic mechanism of the eye.
An eye naturally tends to adjust its shape so that it sees focused images on the retina. By focusing the images slightly in front of the retina, or so-called myopic defocus, the eyeball tends to shorten itself to receive the images. The principle of the new method is to produce a clear image on the retina and a defocused or blurred image in front of the retina simultaneously. In this way, the wearer can enjoy a clear and comfortable vision while myopia progression is being controlled.
This technology has been applied to Defocus Incorporated Soft Contact (DISC) lens and Defocus Incorporated Multiple Segments (DIMS) Spectacle Lens. Our clinical trial shown that DISC lens and DIMS lens retarded the progression of myopia by approximately 60% in Hong Kong school children aged 8 to 13.
Defocus Incorporated Soft Contact (DISC) lens
The DISC lens is a multi-zone bifocal soft contact lens which comprises optical zones for correcting refractive error and “positive” defocus zones for myopia control. It won a Grand Prize and a Special Gold Medal at the 39th International Exhibition of Inventions of Geneva in 2011. A PolyU supported start-up, VST, has been licensed for the production of DISC lens, which is available on the market. PolyU also prescribes DISC lens at its Optometry Clinic and provides training in fitting the DISC lens on the eyes for optometrists.
