Presbyopia is a refractive eye condition that presents in adult patients after age 35. Do you have it?
Of all of the signs and symptoms of midlife, fewer are more aggravating than presbyopia. Its chief characteristic, the loss of ability to focus on near objects, plays to stereotypes of the grandmother with thick bifocals, the librarian with glasses on a neck-strap, the bald socialite with a monocle or pince-nez, or the scatterbrained parent with reading glasses scattered about the house.
It is often seen as an unwelcome life transition for people used to wearing plain eyeglasses or contact lenses and can be terrifying for people who, until their forties, never required glasses at all.
Just what is presbyopia?
Before we go any further, here’s a cute, short video from VisionCareUK to introduce you to presbyopia. Enjoy!
What are the symptoms of presbyopia?
Most people first notice presbyopia in low-light conditions or when trying to read fine print. Menus in dimly-lit restaurants, especially, become troubling. “Tromboning”, that is, extending your arm while holding reading material, is common.
Early symptoms can be more subtle, such as difficulty transitioning between distance and near without blur, headaches, or eyestrain when reading.
What causes presbyopia?
Prior to age 40, the need for glasses is dictated by the size and shape of a person’s eyes. The physical eyeball, when too long or too short, causes light to focus far from, or short of, the back of the eye. This causes a blurring effect.
More often, the cornea, that clear dome in the front of the eye on which a contact lens might rest, can be too flat or too steep, causing similar problems. These difficulties are well-corrected with an average pair of prescription eyeglasses or contact lenses, which re-focus the light onto the back of the eye.
Presbyopia, however, is not caused by the size and shape of the eyeball or cornea, but rather by the lens, a part of the eye about the size of an M&M that sits out-of-sight, behind the colored part of the eye.
Flexibility of the lens is required to adjust focus between reading and distance vision. As the human body ages, the lens becomes hard and loses flexibility. This change in flexibility starts in very early life but rarely becomes symptomatic until the fourth or fifth decade.
As the lens continues to lose flexibility, stronger reading glasses are needed. This often makes a person feel like their earliest pair of reading glasses “create dependency,” though the eyes would worsen, regardless.
How does one treat presbyopia?
Glasses remain the most common treatment for presbyopia. For contact lens wearers and people with perfect distance vision, a simple pair of reading glasses will often suffice. People already wearing glasses for mild myopia will find that they can remove their glasses to read small print. For others, a progressive or bifocal eyeglass lens, which blends a distance lens in the top half with a reading lens in the bottom, is the best answer.
The past quarter-century has seen numerous innovations in presbyopia treatment: multi-focal contact lenses that combine near and distance zones, lens implants, and laser surgery techniques for blending vision are becoming more common. Correcting one eye for distance and the other for near, a technique known as monovision, is satisfactory for many.
What attitude should we take?
Patient expectations should be realistic in managing presbyopia. There are no eye exercises that can keep it from occurring, and even the best doctors cannot “fix it” or “make it like it used to be.”
Indeed, presbyopia is a life transition that requires adaptation, and some patients adapt better to change than others. We hope this explanation prepares you, so that there are no surprises.
See your eye care professional for a solution that’s best for you!
Contributed by:
Curt Sembello