Contact Lens Update

Craig Woods, PhD Craig is Director of Optometric Clinical Studies at Deakin University, Australia

Presbyopia is an inevitable condition. Its arrival can be dramatic and frustrating, requiring time for the individual to accept and subsequently adapt to the limitations it imposes. It is also a visual burden of significance both to the individual and for the general population. A 2009 United Nations report stated that 11% of the world’s population was over the age of 60, and that it was expected to double by 2050,¹ independent of country (Figure 1).

This presbyopic burden will have an increasing impact on eye care practitioners as they experience an increasing proportion of patients needing near vision correction at the same time that they develop concerns about ocular health associated with aging.

Considering contact lenses

Contact lens wearers will be similarly affected. In 2010, Morgan et al.² reported that

[The] proportion of those in the presbyopic age range (>45 years) being fitted or refitted with contact lenses has increased dramatically over the survey period, especially in the European countries surveyed. Between 2000 and 2008, this proportion increased from 18 to 29 percent of wearers in the Netherlands, 11 to 28 percent in Norway and 20 to 27 percent in the UK (Figure 2).

Using contact lenses to correct presbyopia can be a challenge, as we know presbyopia continues to be high on the list of reasons for discontinuation of contact lens wear. Recent data reported by Dumbleton et al.³ is in agreement with data reported by Weed et al.⁴ 18 years ago: The number one reason for contact lens drop-out continues to be discomfort, with presbyopia high on the list.

The primary optical challenges of multifocal contact lenses are the visual aberrations induced by simultaneous vision or lenses with a concentric design. With monovision, some patients have difficulty suppressing either distance or near vision. Although there are a few translating soft lens multifocals, they are far from mainstream yet, but the right design would be the magic bullet. Of course, translating multifocal rigid gas permeable lenses work well for some patients. There is no panacea, but judicious choice with trial wear of soft multifocal designs to correct presbyopia has become increasingly effective and successful.

Chair time

Woods et al.⁵ reported that the chair time required to fit presbyopic patients with contact lenses— whether with single vision lenses, monovision or a multifocal lens— was equivalent. So considering a multifocal lens as an option is not likely to waste the time of  practitioners or patients.

Improved success with multifocal contact lenses

Over the past few years there have been reports of improved success with use of multifocal contact lenses compared to monovision:

• Richdale et al.⁶ reported 76% success with Soflens multifocals (Bausch and Lomb).
• Benjamin⁷ reported that 69.6% of subjects preferred Proclear Multifocal (Coopervision) compared to monovision.
• Woods et al.⁵ reported that wearers had an overwhelming subjective preference for Air Optix multifocal low add (CIBA VISION) over monovision.
• Ferrer-Blasco and Madrid-Costa⁸ reported very positive results when measuring stereopsis with Proclear multifocals, considered by some to be modified monovision.

 

International fitting trends

In a recent review of the data collected by the International Contact Lens Fitting Consortium, Morgan et al.⁹ wrote that of 16,680 presbyopic contact lens fits, three times more multifocal lenses were fit compared to monovision, mostly to full time wearers lens wearers.

Finding up-to-date information on contact lenses designed to correct presbyopia

Health care providers should be able to rely on evidence-based guidance for the best care of their patients; however, this is problematic for practitioners who wish to provide contact lens care for their presbyopic patients, as there is a paucity of information on this subject in the peer reviewed literature: Only two contact lens-related papers have been published in 2011 so far (Table 1).

Table 1. Results of a literature search for methods of correcting presbyopia

In fact, comparing the number of publications on the general topic of presbyopia to other conditions, considering the extent of its impact on the world’s population, is disappointing (Table 2).

Table 2. Results of a literature search for common eye-related conditions

 
Where to next?

With growing evidence of the success of the newer multifocal designs, it is time to rethink fitting strategies for presbyopic correction. Multifocal contact lenses appear to be an attractive option, and if they don’t work as well as anticipated, monovision or modified monovision can be excellent alternatives.

By far, the most prevalent type of correction for presbyopic patients who wear distance contact lenses is reading spectacles, and that seems to be a very successful option. Both Woods et al.⁵ and Papas et al.¹⁰ recommend that patients should wear trial lenses for at least a number of hours before deciding whether to prescribe lenses, to allow patients to assess, under “real world” conditions, their subjective performance.

Practitioners need a wealth of information and clinical advice, to ensure success with multifocal contact lenses and other forms of presbyopic correction. We encourage you to share that information with us for publication on Contact Lens Update.

REFERENCES

1. World population aging 2009. New York: Report of the United Nations Department of Economic and Social Affairs/Population Division. Document ESA/P/WP/212, 2009.
2. Morgan PB, Efron N, Helland M, Itoi M, Jones D, Nichols JJ, van der Worp E and Woods CA. Demographics of international contact lens prescribing. Contact Lens Ant Eye 2010;33(1):27-29.
3. Dumbleton K, Woods CA, Jones LW and Fonn D. The relationship between compliance with lens replacement and contact lens-related problems in silicone hydrogel wearers. Contact Lens Ant Eye 2011;34(4):216-222.
4. Weed KH, Fonn D, Potvin R. Discontinuation of contact lens wear. Optom Vis Sci 1993;70(12s):140.
5. Woods J, Woods CA, Fonn D. Early symptomatic presbyopes – what correction modality works best? Eye Contact Lens 2009;35(5):221-226.
6. Richdale K, Mitchell GL, Zadnik K. Comparison of multifocal and monovision soft contact lens corrections in patients with low-astigmatic presbyopia. Optom Vis Sci 2006;83:266-273.
7. Benjamin W. Comparing multifocals and monovision. CL Spectrum 2007;22:35–39.
8. Ferrer-Blasco T and Madrid-Costa D. Stereoacuity with balanced presbyopic contact lenses. Clin Exp Optom 2011;94(1):76-81.
9. Morgan PB, Efron N and Woods CA, The International Contact Lens Prescribing Survey Consortium. An international survey of contact lens prescribing for presbyopia. Clin Exp Optom 2011;94(1):87-92.
10. Papas E, Decenzo-Verbeten T, Fonn D. Holden BA, Kollbaum PS, Situ P, Tan J and Woods CA. Utility of short-term evaluation of presbyopic contact lens performance. Eye Contact Lens 2009;35(3):144-148.