ATHLETES AND LENSES
Prescribing Lenses for Athletic Patients
Sports participants often have specialized contact lens wants and needs to achieve optimal performance.
By Kristine Dalton, OD, PhD, MCOptom, FAAO, FBCLA, & Gavin Rebello, BSc(Hons), MCOptom, dipSpVis, dipScVis
Clear vision is crucial for success in many sports, and athletes agree. A survey conducted in 2007 by The Vision Care Institute, LLC, a Johnson & Johnson company, and the United States Olympic Committee (USOC) found that 87 percent of U.S. Olympic athletes and hopefuls believed that vision played an important role in their success in their sport (Falcetti and Esterow, 2007). Yet, despite generally spending a great amount of time and money ensuring they have the correct equipment for their chosen sport, athletes often do not give much thought to their refractive corrections.
This is particularly highlighted by the fact that 25% of athletes have never had an eye examination, and approximately 30% of athletes need some form of vision correction (Beckerman and Hitzeman, 2001). Eyecare practitioners working with athletes in their practices need to discuss vision correction with them and can use the tools provided in this article to successfully fit this population.
Refractive Correction Options
When it comes to correcting refractive errors, practitioners have three primary options: spectacles, contact lenses, or refractive surgery. Each modality has significant advantages and disadvantages when compared with the others (Table 1); therefore it is up to the practitioners to make the best choice for their patients’ needs.
• All prescriptions available (including tints)
• Offer some protection
• Prismatic distortion when looking off axis
• Frames slip or can be knocked out of place easily
• Frames can interfere with the peripheral field of view
• Wide range of prescriptions available
• Corrections remain in place and centered on the eye
• Full peripheral field of view
• Comfort can be poor due to dryness or allergies
• Moderate risk of infection
• Limited opportunity to offer tinted lenses
• Freedom from both contact lenses and spectacles
• Full peripheral field of view
• No risk of lens loss or damage
• Limited range of prescriptions that can be corrected
• Issues with vision quality (glare, halos, contrast sensitivity)
• Risk of injury (flap dislocation with LASIK, globe rupture with astigmatic keratotomy/radial keratotomy) in contact sports
By and large, contact lenses are the refractive correction of choice for athletes, as demonstrated by Pfeiffer et al (2007) in a study of alpine skiers. The study found that 85.7% of alpine skiers preferred the comfort and visual quality of contact lenses for sports despite spectacle lenses providing better visual acuity and contrast sensitivity (Pfeiffer et al, 2007).
With regard to refractive surgery, studies have shown that quality of life scores are improved with refractive surgery compared to spectacles or contact lenses (Pesudovs et al, 2006), but a number of other factors need to be considered in the athletic population. Studies have shown that traumatic LASIK flap injuries are a concern for athletes in contact sports, even years after surgery (Beran et al, 1995; Tetz et al, 2007). Furthermore, despite improvements in technology, the risk of surgical or postoperative complications is approximately 7% (Pesudovs et al, 2006). Additionally, some patients continue to have issues with the quality of their vision after surgery (i.e., glare, halos, prescription regression), which can be very debilitating in athletes. Therefore, contact lenses still offer a safer, more predictable vision correction option for athletes compared to refractive surgery.
Fitting Contact Lenses
When fitting contact lenses for sports, a number of things need to be considered including the patient’s refractive error, the visual demands of the sport, the sport environment (i.e., indoors or outdoors), the patient’s motivation, and the lens cost. However, the most important parameters to consider when fitting contact lenses for sports are the lens modality and the refractive error.
Modality When choosing a contact lens modality for athletes, you want to maximize visual performance, comfort, and convenience while minimizing the risk of infection and complications. Daily disposable lenses offer a reasonably good range of prescriptions and are associated with minimal risk of infection (2.0 per 10,000) (Stapleton et al, 2008). They are also very convenient because they are inexpensive to replace and do not require care solutions or cases. For these reasons, daily disposable contact lenses are our first modality of choice for sports vision patients.
Two-week and monthly replacement contact lenses offer a far greater range of prescriptions compared to daily disposables, and they have a comparable infection risk (1.9 per 10,000 for hydrogels, 11.9 per 10,000 for silicone hydrogels) (Stapleton et al, 2008); but, they are less convenient because they require the use of care solutions and cases. Two-week and monthly replacement soft contact lenses are our second modality of choice for sports vision patients; they are our first modality of choice for patients who have higher prescriptions.
Quarterly and annual replacement soft contact lenses offer an extensive range of prescriptions, but are less convenient because they are expensive to replace and also require the use of care solutions and cases. Prescribe these lenses for athletes only in instances in which a patient’s prescription is not available in either of the aforementioned modalities.
Traditional, daily wear GP lenses also offer an extensive range of prescription corrections with minimal infection risk (1.2 per 10,000) (Stapleton et al, 2008), but are rarely used in sports vision patients because they are easily knocked out of place and lost, they require the use of care solutions and cases, and they are expensive to replace.
Orthokeratology lenses, conversely, offer a nice alternative to athletes who do not want to wear lenses during the day, and they are an excellent option from a convenience perspective. For this reason, they are our third modality of choice for sports vision patients. The greatest drawback of orthokeratology lenses is that they do not work for all prescriptions.
Scleral and semi-scleral options have the potential to provide the extensive prescription range of traditional, daily wear GP lenses without the inconvenience of being easily dislodged from the eye. The biggest concern with these lenses is whether or not they would damage the eye in the event of ocular trauma. To date, scleral and semi-scleral lenses are not commonly used in sports vision patients, but this may change in the future.
Refractive Error Sports are visually demanding, so correcting small refractive errors can make big differences to athletes. The literature suggests that correcting low amounts of hyperopia and myopia (e.g., +1.00D or –0.25D), small cylinders (e.g., –0.50D), and small amounts of anisometropia is often advantageous to athletes, particularly those who play under floodlights or who play fastball sports (Erickson, 2007). To ascertain that the contact lens correction is beneficial, high-contrast visual acuity charts should measure at least 20/15 (6/4.5), although 20/10 (6/3) is preferred. Low-contrast visual acuity or contrast sensitivity also should be measured.
Other Considerations Contact lenses need to be stable to minimize problems with blur, especially toric contact lenses and contact lenses for high-speed sports. The best way to ensure lens stability is to fit the tightest lens possible that does not cause physiological damage to the eye. If it is not possible to change the lens base curve, changing the lens material can sometimes improve the fit, even if the base curves of the two materials are similar.
In addition to the general considerations described above, a number of sport-specific, or at least environment-specific, items need to be considered to ensure a successful fit.
Ultraviolet (UV) Exposure UV exposure increases by approximately 4% for every 300m gained in altitude and during the winter months, due to snow that can reflect up to 80% of UV rays (McKenzie et al, 2007). Therefore, UV exposure is a concern for all outdoor sports athletes, particularly winter outdoor-altitude sports athletes such as skiers and snowboarders. Some soft contact lenses provide UV protection, and these should be used for all outdoor athletes when possible. Unfortunately, the UV-blocking soft contact lenses do not provide UV protection to the conjunctiva or ocular adnexa, so athletes should also wear wrap-around sunglasses or goggles if permissible in their sport.
Seasonal Allergies Pollen and grass allergies are very common and affect more than 40 million Americans (www.aafa.org/display.cfm?id=9&sub=30). They can be a significant problem in contact lens-wearing athletes, particularly in those who play outdoor sports. The best way to minimize the negative effects of seasonal allergies is to be prepared in advance: prescribe a combination anti-histamine/mast cell stabilizer before allergy season starts and provide your athletes with artificial tears to use throughout the season. In patients who are especially prone to allergy symptoms, use daily disposable lenses combined with artificial tears and cool compresses to improve comfort (Stiegemeier and Thomas, 2001).
Dryness Both summer and winter sports athletes can suffer with environmental dryness issues. In the summer, dryness is caused by exposure to higher temperatures and to dusty or windy environments; in the winter, dryness is related to the relatively low atmospheric humidity. Exposure to high altitudes has been shown to decrease tear breakup time and increase tear osmolarity (Willmann et al, 2012); therefore, athletes who participate at high altitudes can also suffer symptoms of dryness. Furthermore, dryness symptoms can be exacerbated in high-speed sports such as downhill skiing, luge, and skeleton, in which athletes attain speeds of 85mph to 95mph.
The best way to combat contact lens dryness in these individuals is to be prepared; provide them with artificial tears the first time you fit them with contact lenses, and during follow-up visits proactively remind them to continue their use. Goggles or sunglasses can also be worn over lenses to protect the ocular surface from wind and dust.
Temperature (Winter Sports) While the ocular surface temperature is approximately 34°C (93°F) (Efron et al, 1989), winter temperatures can fall well below -40°C (-40°F), particularly in sports such as dog sledding in the Arctic. Fortunately, temperature alone is not a contraindication for contact lens wear. It can cause degradation of the tear film quality (Maruyama et al, 2004; Butovich et al, 2010), but it minimally affects the contact lenses themselves (Socks, 1982).
Lens Loss (Water Sports) Athletes are often concerned about and experience lens loss in water sports, particularly high-impact water sports such as waterskiing. Interestingly, a study looking at lens loss in waterskiing specifically found that on 119 trials, no lenses were lost, despite the head being fully submerged on 76% of those trials. The authors hypothesized that lenses were not lost because seawater may have caused them to tighten and the blink reflex may have protected them (Galkin and Semes, 1983).
Therefore, when fitting lenses for these types of athletes, it is important to ensure that the lens remains in place with a strong blink. Furthermore, such athletes can wear goggles to prevent lens loss if permissible in their sport. For sports in which goggles are not permitted (e.g., water polo), orthokeratology lenses are an ideal solution; daily disposables are a good second choice.
Infection While microbial keratitis is a concern in athletes and contact lens wearers alike, it is particularly concerning for athletes participating in water sports. Research has shown that wearing daily disposable lenses in conjunction with protective goggles during water sports reduces contact lens microbial contamination (Wu et al, 2011). Goggles should be recommended for all water sports athletes, if permitted in the sport. If it is not possible for the athletes to wear protective goggles, they should be fit with either orthokeratology lenses or with daily disposable lenses that they should discard immediately after their sport. If daily disposable and orthokeratology lenses are not options for prescription reasons, instruct athletes to remove their lenses and to clean and disinfect them immediately after their sport.
Contact Sports Sports-related eye injuries account for approximately 9% of all eye injuries requiring medical attention, and they are the leading cause of eye injuries in children (Gordon, 2012). Blunt trauma or foreign objects in the orbit, such as hockey sticks, tennis balls, fingers, and elbows, cause most of these injuries. Unfortunately, contact lenses do not provide any protection against these types of injuries, and it is crucial for practitioners to remind contact sport athletes of this. Safety spectacles should be worn in addition to contact lenses in high-risk sports (e.g., racquetball), if permissible. In high-risk sports for which safety glasses are not permitted (e.g., rugby), teach athletes how to find a lens in the eye if it has moved off of the cornea. They also should carry emergency-use, unit-dose saline in their equipment bags. In the case of an ocular injury, coaches, trainers, and emergency staff need to be aware that athletes are wearing lenses. You can simply provide athletes with a wallet card that identifies them as a contact lens wearer.
Fitting contact lenses for your athletic patients is a great way to build your practice and improve patient satisfaction. Choosing an appropriate modality for your athletes and troubleshooting issues before they occur will help to greatly improve your success in this population. Remember, athletes wear specific equipment to play their sport, so they should have a sport-specific contact lens prescription as well. CLS
For references, please visit www.clspectrum.com/references.asp and click on document #222.
Dr. Dalton works at the School of Optometry & Vision Science at the University of Waterloo and is in the process of establishing a sports vision research center at the school. She studied for a PhD in sports vision at Aston University. She can be reached at email@example.com.
Gavin Rebello is a UK-based optometrist with a special interest in vision performance, particularly in sports, as well as how vision impacts reading skills in children. He has been an advisor to Johnson & Johnson and has received lecture or authorship honoraria from Johnson & Johnson and Alcon.