Karen is a Clinical Scientist at the Centre for Ocular Research & Education, (CORE) with additional responsibilities focussing on the educational programmes provided by the centre. She has previously worked as a Professional Affairs Manager in the contact lens industry, and in practice in the UK. She holds a post graduate diploma in Clinical Optometry from City University, London UK, and is a Fellow of the International Association of Contact Lens Educators.
Contact lens fitting practices are, of course, influenced by a wide variety of factors, including those detailed in Table 1. The experience gained across all of these areas naturally create beliefs for the practitioner that ultimately influences what they choose to fit and recommend to patients.
Table 1: Factors influencing contact lens prescribing practices
| Factor | Examples |
| Patient | Expectations, wearing habits, lifestyle |
| Ocular | Refraction, ocular surface health, condition of the tear film |
| Contact lens | Material, modality, prescription availability |
| Financial | Cost to patient, chair time in practice, success rates |
While it is difficult to obtain accurate figures of the numbers of contact lens wearers worldwide, it is generally reported that the overall value of the contact lens market continues to grow.1 This should, however, not simply be interpreted as increasing numbers of people wearing contact lenses. Market value grows as prices increase, and the trend of refitting into daily disposables from reusable modalities is a simple illustration of how market value can increase without increasing wearer numbers.
It is even more difficult to assess absolute numbers of contact lens wearers and drop outs globally. A 2017 report estimated there are 45 million contact lens wearers in the US,2 but it hard to find a widely cited global figure. In terms of those who permanently drop out from contact lens wear, estimates range from 12-43%.3-6 It is difficult to assess the proportion of drop outs each year: practices often do not know, patients do not report it, and definitions of drop out vary by study. Given those challenges, a recent prospective study followed neophytes fit with contact lenses over one year. The intention was to understand early retention in the category, and investigate the reasons for ceasing lens wear. By the end of that period just over one-quarter (26%) had dropped out, with the major reasons cited as issues with vision, adequate comfort and handling concerns.7
In spite of the difficulties in obtaining absolute figures, consensus exists about the opportunity to grow the contact lens market further: many more spectacle wearers could wear contact lenses of course, former lapsed wearers can be successfully refit, and current wearers, managed well, can be prevented from dropping out.
Given the opportunity to grow, are current fitting practices sometimes constrained by long-held beliefs? Do these limit the conversations held with patients? This edition of contact lens update looks to address three commonly held beliefs. In our feature article Lyndon Jones reviews the clinical performance of daily disposable silicone hydrogels and discusses some of the barriers which may prevent eye care practitioners from routinely recommending them. The conference highlights section, summarised by Jill Woods, reviews current attitudes to multifocal contact lens fitting, and shares the results of more recent data that supports taking a more proactive approach with presbyopes. Finally, practitioner attitudes to the prescribing of soft toric contact lenses to low astigmats are summarised by Karen Walsh in the clinical insights section.
For all of these subject areas – daily disposable, toric and multifocal fittings – we establish if a review of the evidence supports the long-held belief or fitting practice, and ultimately, using the most up to date available knowledge, determine the current best advice to take into practice.
REFERENCES:
- Nichols J. Continuing upward trends in daily disposable prescribing and other key segments maintained a healthy industry. Contact Lens Spectrum 2018;33(January):20-5.
- Cope JR, Collier SA, Nethercut H, Jones JM, Yates K, Yoder JS. Risk Behaviors for contact lens–related eye infections among adults and adolescents — United States, 2016. MMWR Morb Mortal Wkly Rep 2017;66(32):841-5.
- Pritchard N, Fonn D, Brazeau D. Discontinuation of contact lens wear: a survey. Int Contact Lens Clin 1999;26:157-62.
- Richdale K, Sinnott LT, Skadahl E, et al. Frequency of and factors associated with contact lens dissatisfaction and discontinuation. Cornea 2007;26:168-74.
- Rumpakis J. New data on contact lens dropouts: An international perspective. Rev Optom 2010;January:37-42.
- Dumbleton K, Woods CA, Jones LW, et al. The impact of contemporary contact lenses on contact lens discontinuation. Eye Contact Lens 2013;39:93-9.
- Sulley A, Young G, Hunt C. Factors in the success of new contact lens wearers. Cont Lens Anterior Eye 2017;40:15-24.
