There are some natural problems that come with age. Joints get a little creaky, hair loss sets in… and your eyes don’t work like they used to. Your optometrist tells you that you have presbyopia – but what is presbyopia and why does it happen?
What is Presbyopia?
Simply, presbyopia is the natural age-related deterioration of the eye’s focusing ability. Within the eye is the crystalline lens, which sits just behind the coloured iris. At birth, a normally developed lens is optically transparent to allow the transmission of light, and is also quite flexible. Attached to fibres and controlled by a ring of muscle called the ciliary muscle, this lens is able to change its shape to focus on near objects – a process called accommodation.
However, as we age, the lens grows increasingly less flexible. As we approach our mid-40s we begin to find that we can’t focus on near objects as easily or clearly as we once could – this is early presbyopia.
Although there are several options to correct presbyopia, in the early years you may find easy ways of getting around it, such as simply holding your reading material further away or enlarging the font on a digital device. However, presbyopia is progressive and unrelenting and eventually you will find that your arms are simply not long enough to easily read your books.
There is currently no cure for presbyopia or any way to slow it down. Some international research is looking into the use of pharmaceuticals but currently this age-related deterioration of near vision is just something to accept as part of getting older and wiser.
How Do You Correct Presbyopia?
Now that we’ve identified what is presbyopia and come to accept that it’s natural with age, we can look into the available solutions.
The most popular way to correct presbyopia is with glasses. There are several designs of spectacle lenses that may suit different lifestyles and activities.
- Single vision reading spectacles: The entire lens contains the reading, or near vision, script. To look at distant objects you’ll need to remove the glasses or peer over them.
- Extended focus spectacles: Due to the progressive nature of presbyopia, at some point you will find that the one reading script is no longer clear for both an intermediate arm’s-length distance and a closer reading distance. Extended focus spectacles contain your intermediate script in the top half of the lens and a stronger near script at the bottom half, meaning you don’t need two pairs of near vision glasses for different activities.
- Multifocal glasses: Multifocals contain your script all the way from far-distance vision to up-close reading vision. The change in the script throughout the lens is progressive and gradual, with long-distance at the top, through intermediate vision in the middle, to near vision at the bottom.
- Bifocal glasses: Bifocals contain a visible line on the lens; below the line is typically the near vision script while every other area of the lens is used for long-distance vision. There is no intermediate script in a bifocal.
The advancement of contact lens design has also made it a viable option for presbyopia correction.
- Monovision: One eye is corrected with a contact lens for distance vision while the other is given a contact for near vision.
- Multifocal contacts: Both eyes are corrected for some degree of distance and near vision, with the dominant eye given a preference for distance viewing. The brain learns to adapt around the concept of simultaneous vision.
Certain refractive surgical procedures may be suitable to correct presbyopia, depending on various factors such as your prescription and ability to adapt to a different visual experience.
- Presbyond: A variation of LASIK surgery, Presbyond laser blended vision reshapes the front surface of the eye to change the passage of light through it, providing clear sight at both distance and near.
- Multifocal intraocular lenses (IOL): Similar to a multifocal contact lens, a multifocal IOL is an implantable lens that contains correction for both distance and near viewing. This can be inserted during a refractive lens exchange (RLE) procedure or during cataract surgery.
- Monovision IOLs: During an RLE procedure or cataract surgery you may opt to have an IOL implanted for distance vision in one eye and one for reading in the other eye.
Whether you are experiencing the early or later stages of presbyopia, be assured it’s a normal part of ageing and you have a multitude of corrective solutions available to you.
Note: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner.