New vision options for patients over 40
By Zack Steele
Our practice has a fair share of patients with presbyopia, or the loss of ability to focus on words or objects in close. People commonly say “my arms aren’t long enough anymore.” For those patients past 40 years old, this can be a frustrating time. Focusing ability goes in and out. Eyestrain at the end of the day is common. In our profession, these are our most frustrated (and often frustrating) patients because they will never have the vision they once had.
Several years ago, you may have tried the progressive lens, or the no-line bifocal. You may have also had many problems with the early designs of this lens.
Progressive lenses are corrective lenses used in eyeglasses to correct presbyopia and other disorders of accommodation, or the ability to focus. A gradual increase in lens power is added to the correction for the distance correction, going from a minimum or nothing at the top of the lens to maximum magnification at the bottom of the lens. A wearer can then adjust the lens power required for clear vision at different viewing distances by tilting his or her head to place the line of sight through different parts of the lens.
For those new to progressive lenses, an accommodation period is required. Basically, the brain needs to learn to work with them. This period varies from a few days for some individuals to a couple weeks. During this period, side effects can include headache and dizziness.
Progressive lenses can also produce distortion — lines and surfaces do not appear as straight. This is most likely to appear in the lower half of the lens where the near prescription is blended in. It’s noteworthy that all lenses (single vision included) with power can cause the same effect in their periphery, causing straight lines to appear bent. For these reasons, many patients give up on the progressives because they understandably can’t tolerate the side effects.
The technology today is improved to the point that I always revisit the idea of progressives with patients who have had those problems in the past. By taking advantage of the newest technology, patients can experience the full range of vision, with minimal distortion and a reduced accommodation period. Most patients who try these lenses do well after a few days.
Are progressive lenses right for you? I would recommend talking to your eye care professional about progressives and other options for improving near vision.
Dr. Zack Steele is a 2003 graduate of UAB School of Optometry. His practice, Trussville Vision Care, is located on Chalkville Road in downtown Trussville.