By Brian Chou, OD, FAAO
Despite the emphasis on evidence-based practice in our optometric curriculum and continuing education courses, the reality is that tradition, corporate interests and group-think influence eyecare practitioners in several ways that may not make sense. Let’s look at eight myths that we should be aware of and prepared to counter.
Myth #1: Single-use contact lenses are safest.
It sounds logical to say that single-use contact lenses are safest. After all, the patient starts with a fresh lens without accumulated bacterial contamination each day. Yet a study published in 2008 in Ophthalmology by Dart, et al., found an increased rate of microbial keratitis in single-use contact lens wearers. A review by Stapleton and Carnt, published in 2012 in Eye, stated that, “…the risk of infection associated with daily disposables contact lenses is of a similar magnitude to that of other daily use lenses….” Either way, single-use contact lenses do not seem to reduce the risk of vision-threatening microbial keratitis in a compelling fashion. Still, this modality is convenient and is associated with a low incidence of deposit-related issues, and the market growth in the US to approximately 20 percent of contact lens sales validates these benefits.
Dart JK, Radford CF, Minassian D et al. Risk factors for microbial keratitis with contemporary contact lenses: a case control study. Ophthalmology. 2008;115:1647-54.
Stapleton F, Carnt N, Contact lens-related microbial keratitis: how have epidemiology and genetics helped us with pathogenesis and prophylaxis. Eye (Lond) 2012 February; 26(2): 185–193. Published online 2011 December 2. doi: 10.1038/eye.2011.288
Myth #2: Antioxidants prevent macular degeneration.
Under the Dietary Supplement Health and Education Act (DSHEA) of 1994, manufacturers of “dietary supplements,” including antioxidant vitamins and minerals, are not required to prove efficacy of their products to the FDA. The loose regulatory space of dietary supplements creates confusion to consumers and practitioners alike. Specifically with macular degeneration, the 2014 Cochrane review meta-analysis of four large, high-quality randomized controlled trials involving 65,250 participants found that, “…there was no significant effect of antioxidant therapy for preventing the onset of AMD, per se.” According to Downie and Keller in a recent Optometry & Vision Science article on macular degeneration, “…the clinical implications of these findings are that there is currently no evidence from RCTs (randomized controlled trials) for patients who do not show signs of AMD to consume antioxidant vitamins and/or mineral supplements to prevent or delay the onset of AMD.”
Evans JR, Lawrenson JG. Antioxidant vitamin and mineral supplements for preventing age-related macular degeneration. Cochrane Database Syst Rev 2012;6:CD000253.
Downie LE, Keller PR. Nutrition and age-related macular degeneration: research evidence in practice. Optom Vis Sci 2014;91:821-831.
Myth #3: Wide-field retinal imaging replaces dilated fundus examination.
Wide-field retinal imaging by Optos is an impressive and useful technology, yet a surprising number within our industry, as well as consumers, believe this technology can supplant dilated fundus examination. In 2003, I published in Optometry & Vision Science an Optomap image of an encircling scleral buckle, which demonstrated how this technology misses peripheral retina. In 2007, an article in Retina by Mackenzie et al. found that in patients with known retinal pathology anterior to the equator, more than half of the time, retinal specialists evaluating the Optomap failed to identify the pathology. Practices adopting this technology are incentivized to sell this a-la-carte measurement, to cover a per-use fee and monthly use minimum. To achieve this, some staff will confront patients with eye dilation as an uncomfortable alternative to the Optomap, which can send the unfortunate message that the Optomap and dilated fundus examination are equivalent. The better approach is to educate patients that this technology can reduce the likelihood of eye dilation, while also providing a permanent photo record for future comparison.
Chou B. Limitations of the Panoramic 200 Optomap. Optom Vis Sci 2003;80: 671-672.
Mackenzie PK, Russell M, Patrick E, et al. Sensitivity and specificity of the Optos Optomap for detecting peripheral retinal lesions. Retina 2007;27(8): 1119-1124.
Myth #4: Hyperosmotic ointment effectively treats recurrent corneal erosions (RCEs).
Many practitioners recommend that patients with recurrent corneal erosions use Muro 128 (2% or 5% NaFl). The concept is that hyperosmotics draw fluid out of the epithelium, facilitating adhesion to the basement membrane. Yet the Cochrane review of interventions for recurrent corneal erosions identified two studies that found that hyperosmotic ointments did not offer better prophylaxis than regular ointment.
Watson SL, Lee MH, Barker NH. Interventions for recurrent corneal erosions. Cochrane Database Syst Rev. 2012 12:9:CD001861.
Myth #5: Blue light is all bad.
The treatment du jour seems to be blue-blocking lens treatments. Suggestions abound in our industry that blue light is villainous, like UV light. Although in vivo evidence implicates blue light toxicity to the retina, there is actually no in vivo evidence that has shown that blue light causes or exacerbates retinal disease, like macular degeneration. According to a 2011 review article by Youssef in Eye, “Many investigators remain skeptical regarding the role of blue blocking lenses as most patients with macular degeneration are phakic at the time of diagnosis and have developed disease despite the protective tissue optics of the aged natural crystalline lens.”
Some blue-blocking treatments may disrupt circadian rhythms. Blue light is known to stimulate melatonin release by the pineal gland. Furthermore, some studies have also implicated blue light exposure as a factor in limiting myopic progression.
The bottom line is that practitioners should know that blue light is implicated with retinal damage, but that the exact relevance of blue-blocking treatments is not solidified. Each practitioner should make their own decision on how much evidence they require to promote blue-blocking treatment.
Chellappa SL, Steiner R, Oelhafen P, et al. Acute exposure to evening blue-enriched light impacts on human sleep. J Sleep Res 2013 (22):573-80.
Youssef PN, Sheibani N, Albert DM, Retinal light toxicity. Eye. 2011; 25(1):1-14.
Foulds WS, Barathi VA, Luu CD. Progressive myopia or hyperopia can be induced in chicks and reverse by manipulation of the chromaticity of ambient light. Invest Ophthalmol Vis Sci. 2013; 45(13):8004-12.
Myth #6. Digitally-surfaced progressives guarantee optical bliss.
Digital surfacing is a method of manufacturing which alone does not guarantee an optimal visual experience. In fact, a poor progressive lens design can undermine the benefits of digital surfacing. This is analogous to having a poorly composed photograph available as a 30 MB file. It’s still a bad photograph even if it’s 30 MB in size. A good progressive lens design that’s molded will outperform a poor progressive design that’s digitally surfaced. The ideal situation is having a superb progressive design that’s digitally surfaced.
Myth #7. Routine dilated examination is necessary.
Good evidence exists that routine dilated examination on every patient is unnecessary and not cost effective. Batchelder et al, published their results in 1997 in Archives of Ophthalmology, which found that most peripheral retinal diseases cannot be prevented by routine dilated examination. The authors also concluded that routine dilated examination is an expensive test per prevented case of vision-threatening retinal disease, in their estimation costing the provider $433,000 per prevented case.
A more prudent approach may be selectively dilating patients that are at-risk, for example, those with hypertension, diabetes, high myopia, family history of ocular disease–and certainly those with symptoms that may signal retinal pathology.
Bullinore MA. Is routine dilation a waste of time? Optom Vis Sci. 1998; 75:161-2.
Batchelder TJ, Fireman B, Friedman GD, Matas BR, Wong IG, Barricks ME, Burke S, Beasley L. The value of routine dilated pupil screening examination. Arch Ophthalmol 1997; 115: 1179–84.
Myth #8. Educate patients about the signs and symptoms of retinal detachment.
In my review of medical records as an expert witness for legal matters, I have often observed documentation to the effect of educating patients about the “signs and symptoms” of retinal detachment. But wait a minute–signs are objective findings, whereas symptoms are subjective. Do you really teach patients to look for signs such as Schaeffer’s sign, reduced intraocular pressure in the affected eye, an afferent pupillary defect, or an elevated retina on biomicroscopy? Obviously not. We only educate patients on the symptoms of retinal detachment, and for that reason, you should document that alone.
Have you fallen prey to any of these myths, or do you disagree that any of these are, in fact, myths? How do you ensure you are up-to-date on all the latest research so you are able to most effectively guide and treat patients?