Presbyopia is simply stated as a weakening of our ability to focus on objects at near distance. It is due to a lessening of flexibility of the crystalline lens, as well as to a weakening of the ciliary muscles which control lens focusing, both attributable to the aging process.
With the development of progressive lenses, eye care professionals and patients alike have a dynamic optical correction modality to work with. Progressive lenses are characterized by a gradient of increasing lens power added to the wearers’ correction. The gradient starts at a minimum or no addition power at the top of the lens and reaches a maximum addition power, magnification, at the bottom of the lens. The length of the progressive power gradient on the lens surface is usually between 12 and 20 mm with a final addition power between 1.00 to 2.50 diopters for most wearers. The addition value prescribed depends on the level of presbyopia of the patient and is closely related to age. The wearer can then adjust the additional lens power required for clear vision at different viewing distances by tilting his or her head or eyes through the appropriate part of the vertical progression.
It is important to note that new progressive lens wearers will require to go through a short period of adaptation; the brain needs simply to learn how to work and adopt to those advanced optical devices.
The period of adaptation varies from few days to couple of weeks at maximum for some individuals. During this period, wearers might experience some side effects which can include headache and light dizziness.
Progressive lenses are currently quite advanced. Newer designs come with wider intermediate zone and a much lesser peripheral or optical distortion thus offering the wearer comfortable transition from distance to near and faster adaptation.
Progressive lenses are available in plastic, polycarbonate, high-index and photochromic polymers.
“At VISIQUE Optometrists, we highly recommend tinted polymers widely known as transition. This modality offers optimal performance for presbyopic correction.”
Successfully fitting progressive lenses is key to offering an optimization in eye performance. Choosing the right product is important. However, this must be done by also insuring the appropriate professional measurements are meticulously taken along with considering various wearers lifestyle priorities; such as vision-related work requirements or other personal daily routines. All of this will ensure proper progressive lens fitting thus comfortable vision and lesser adaptation time.
“Progressive lenses represent today the most advanced form of presbyopia correction.”