Anti-High-Index Indicators
ECPs say that while high-index lenses are rapidly becoming a lens-of-choice, they also caution that not everyone is cutout for high-index. These red flags may signal recommendation away from high-index:
1. Rx�s less than 2.50D. It�s hard to see the benefits of a thinner, lighter lens in a low power in a small frame. While these patients may benefit from aspheric and atoric optics combined with AR, the �thinner and lighter� mantra may not fly, as thin appearance and lightweight are less dramatic on lower power lenses.
2. Rimless eyewear. While many ECP�s do successfully dispense high-index lenses in both semi-rimless and drilled rimless frames, some say they take �Duty to Warn� seriously and have an office policy of only poly or Trivex in rimless mountings. Some of today�s high-index materials are specially formulated for rimless processing, dispensing, and wear.
3. Eye turners. Those who tend to turn their eyes instead of turning their head when viewing objects will be more aware of chromatic aberration in the lens periphery. Fortunately, patients with high powered Rx�s � the best candidates for HI � are usually head turners whose primary view is from the lens center.
4. Picky patients. Everyone has a few hypersensitive patients who pick apart every nanometer of their eyewear and get antsy over every change. Most dispensers will tell you not to rock the boat: keep these patients in the same thing they�re wearing including base curve, OCs, and PDs, seg height and type, lens design, color, and lens material. However, some proponents of high-index lenses successfully convert patients from other materials to high-index by spending time throughout the dispensing process educating them on the features, benefits, and nuances of high-index.
5. Image size. Magnification/minification exhibits not only in lens appearance, but some patients notice the change size when viewing objects. Assure patients that this slight change is actually more like true natural vision, and they�ll appreciate it quickly.
6. Wrap-style frames. Because of the extreme curve in the frame, wrap styles generally won�t accommodate flatter HI lenses. Lenses may pop out of the frame both appearance-wise and wearing-wise. Check with your lab before fitting HI lenses in a wrap frame.
High-Index Fitting Tips |
A recap of top HI tips from ECPs: 1. Select a frame that centers
the eye in the lens |