There are exceptions-see “Troubleshooting Mature Presbyopes” on p. Recommendation: Trial frame the Rx outdoors to discover the optimal flip point for achieving best acuity while driving. Further, anything that compromises axial acuity will further degrade peripheral acuity by compounding the inherent peripheral blur of progressive lenses. With the standard exam distance set at 20 feet, which equals a vergence of +0.16D, the final subjective lens choices could easily flip into an undesirable over-plus situation for driving distance. Approach this timeless recommendation with caution. If the wearer experiences perceptual discomfort tracked to their astigmatism correction, try switching to a softer-design progressive.Ģ. ![]() Although satisfaction here is not guaranteed, the prospects for progressive success almost always improve when the eye’s astigmatism is properly and optimally corrected. ![]() Recommendation: Prescribe the full cylinder found and avoid orthogonalizing the axis. 1 This residual astigmatism can interact with any leftover refractive astigmatic error in a progressive lens and decrease acuity and utility. But all progressive lenses possess some residual astigmatism distributed across the lens surface. For this reason, prescribers often reduce or eliminate minor amounts of astigmatism up to 0.50D.Īdditionally, orthogonalizing the axis-adjusting it closer to the prime meridians of 90º or 180º-is often used to further reduce perspective side effects. But prescribing the full astigmatism can come with a price: an alteration of habitual perspective that negatively impacts comfort for some wearers. Full correction of astigmatism delivers the best bang for the buck when chasing optimal acuity. Below is a short list of suggestions that can improve progressive satisfaction:ġ. Although creating the best progressive begins with an accurate refraction, it sometimes goes awry when the well-intentioned prescriber’s discretion influences the final Rx in a way that works against progressive success. By the time a wearer lands in the doctor’s chair for a recheck, usually the Rx is the top suspect behind their eyewear dissatisfaction. Prescription Perhaps nothing impacts a prescriber’s approach more than time spent performing eyeglass rechecks. This squishiness also helps in defining the larger area of wearer satisfaction colloquially called “20/happy,” which can guide in determining the most efficient use of professional time and materials.īut even 20/happy can be elusive, and therefore ECPs should always remain open to novel information as they juggle prescription, progressive design and placement to deliver a superlative progressive experience. The eye/brain’s ability to adapt and function well in a matrix of less-than-optimal conditions, such as eyewear routinely made off-spec or with poor lens materials and centering, can hide what matters most for any individual patient. One of human vision’s biggest advantages-that it’s inherently “squishy,” or adaptable-does hinder choosing the best lens for any individual PAL wearer. Pupil size determines the effective cross section of the eye’s refractive optical train-cornea, crystalline lens and retina-that is contributing to the final refractive result. While challenging, these conditions can be comanaged successfully, and optometrists are in the perfect position to take a leadership role in the care of this sizable patient population. ![]() To help both sides of the dispensing desk arrive at the best solution, let’s start with a review of the fundamentals for dispensing progressive addition lenses (PALs). And while balancing these elements is essential, frame fit, cosmetics and perceived value also remain important ingredients in a successful experience. But despite advances in lens design and manufacture over the last 25 years, ECPs still yearn to discover the perfect progressive-the one design that balances acuity, comfort and utility just right. Ey e care professionals (ECPs) probably spend more time trying to make their progressive wearers satisfied than any other category of eyeglass wearer.
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