The children in the treatment group reported that the DIMS spectacle lens was comfortable, allowed good vision at short and long distances, and good depth perception.
A specially designed spectacle lens slowed down the progress of short-sightedness in a group of children by 60%, and halted it completely in one-fifth of them. The ‘defocus incorporated multiple segments (DIMS) spectacle lens’—designed by optometrists Carly Lam and To Chiho of The Hong Kong Polytechnic University (PolyU) (PolyU) and research collaborator Hoya Corporation—offers a solution for short-sighted children for whom contact lenses are not appropriate.
Short-sightedness occurs when the eyeball is too long relative to the focusing power of the eye’s cornea and lens. Light focuses in front of the retina rather than on it, making distant objects appear blurry.
The DIMS lens eliminates blurriness by containing a central optical zone that corrects refractive error. But it goes a step further, seeking to prevent the condition from worsening. The central zone is surrounded by multiple micro-lenses that extend toward the lens’s periphery. These lenses cause the eye to experience defocus when it looks through them, and this extra ‘work’ actually helps slow or even stop the lengthening of the eyeball, To explains.
To test the DIMS’s effectiveness, 160 short-sighted Chinese children aged 8 to 13 participated in a three-year trial. The eyeball lengths of children using the lens increased less than those who didn’t use it. Eyeballs completely stopped lengthening in 21.5% of the children using the lens, while lengthening stopped in only 7.4% of children not using the lens.
The children in the treatment group reported that the DIMS spectacle lens was comfortable, allowed good vision at short and long distances, and good depth perception.
Severe cases of short-sightedness can cause retinal detachment, which sometimes leads to permanent blindness or visual impairment. “The DIMS spectacle lens helps safeguard children’s vision,” Lam says.
Launched commercially in the summer of 2018, the DIMS lens won several awards at the 46th International Exhibition of Inventions of Geneva in 2018.
For further information, contact:
Professor To Chi-ho | E-mail: [email protected]
Head of the School of Optometry
The Hong Kong Polytechnic University (PolyU)
Professor Carly Lam | E-mail: [email protected]
School of Optometry
The Hong Kong Polytechnic University (PolyU)
Spectacle lens designed by PolyU slows myopic progression.
