Day Lenses - Soft Contact Lenses for Myopia Control
Author: Jason Higginbotham
BSc (Hons) MCOptom Prof Cert Glau Prof Cert Med Ret Prof Cert LV FBDO MBCLA
Specialist Soft Contact Lenses
There are now have several options for contact lenses that help to reduce the rate of deterioration of myopia safely and successfully. These include lenses that are worn overnight to correct the vision and some lenses that work whilst worn during the day. Both of these options give great vision and children usually prefer contact lenses compared to wearing glasses.
The current soft contact lenses designed for myopia management are generally related to the peripheral hyperopic defocus theory of myopisation, where light in the periphery focusses behind the retina leading to the length of the eye increasing. This means that myopia management lenses need to stop peripheral / off centre light rays from being brought into focus essentially behind the eye. Instead, that light needs to be focussed in front of the retina. This is known as a peripheral myopic defocus lens.
The way many of these lenses work means they also adhere to some extent to what is known as the accommodative lag theory of myopisation. Ultimately, the aim is to stop the mechanism that seems to drive the growth of the eyeball. However, it’s very likely that a combination of at least these two mechanisms is at play in progressive myopia
Coopervision MiSight lenses
These lenses have a central normal distance zone and then rings of stronger ‘near’ powered areas, which bring light into focus in front of the retina. There are also rings of normal distance vision to correct sight clearly in all directions for the child. The aim is to slow myopia progression whilst maintaining excellent vision.
There have been many well-reviewed studies showing a high level of efficacy for these lenses.
Mark’ennovy Mylo lenses
These contact lenses are also known as EDOF (extended depth of focus) lenses. It uses a design of lens developed by the BHVI (Brien Holden Institute of Vision), which was the main source of the evidence of the myopia epidemic. EDOF lenses can be used to correct distance and reading vision in older patients, but the design of this lens works differently to the presbyopia-correcting contact lenses.
But, is it safe for children to wear soft contact lenses?
The short answer is yes. Many studies have shown that the rates of infection or poor handling of contact lenses are generally much lower in children, mainly because parents are heavily involved in the whole process of their kid’s eye care.
The contact lens materials are specifically designed to reduce friction on the ocular surfaces and maximise how much oxygen gets through the lens. This ensures that the eyes remain healthy.
The danger of not having myopia management are essentially far higher than not engaging in myopia management in the long term
However if your child really can’t tolerate contact lenses, thankfully there is a new generation of spectacle lenses that have special optics to slow down the progression of myopia.