WALLINE, JEFFREY J. OD, PhD, FAAO; LONG, STACY; ZADNIK, KARLA OD, PhD, FAAO
Myopia is a common disorder. In the United States, myopia is approximately 3 times more common than diabetes. 1 Approximately one-fourth of the United States population has myopia, 2 and nearly 60% (42 million people in the United States) of those affected became myopic during childhood. 3 Most cases of myopia develop between the ages of 8 and 16 years. 4
The primary mode of vision correction for myopia is spectacles, but several alternative options are available. Many types of refractive surgery procedures are available for myopic patients, 5 but they are not viable for children because they provide permanent correction for children’s eyes, which are still growing. Reversible forms of refractive surgery are also performed, 6, 7 but they are not routinely performed in children.
Children can opt to wear contact lenses to correct myopia. Children are able to wear daily-wear rigid gas-permeable contact lenses, 8 daily-wear soft contact lenses, 9 extended-wear soft contact lenses, 10 disposable contact lenses, 11 and overnight corneal reshaping contact lenses. 12 However, the literature currently does not include any information about children wearing daily disposable contact lenses. The comfort and convenience of daily disposable contact lenses make them an excellent potential treatment choice for myopic children.
When considering treatment options for myopia in children, one should think about the efficacy, safety, comfort, and convenience of the treatment modality. Disposable contact lenses provide vision that is as good as that with glasses or rigid contact lenses. 13 Daily disposable contact lenses also have lower complication rates than other modalities of soft daily-wear contact lenses, 14, 15 and they are as comfortable as extended-wear soft contact lenses. 16 Daily disposable contact lenses are more convenient than traditional soft contact lenses, 17 and they are at least as convenient as biweekly replacement soft contact lenses. 18 Furthermore, soft contact lenses do not accelerate the progression of myopia in children. 9
Children wear contact lenses for a variety of reasons, 19–28 but they are not routinely prescribed for myopia. We conducted a case series to assess myopic children’s abilities to wear daily disposable contact lenses.
The study was conducted at The Ohio State University College of Optometry. Parents provided consent for their child’s participation after all study procedures were explained. The research was approved by the Biomedical Sciences Institutional Review Board at The Ohio State University. Subjects who satisfied the entry criteria (Table 1) were fitted with contact lenses. At the baseline visit, the subjects underwent manifest refraction, keratometry, slitlamp examination, contact lens fitting, standardized visual acuity measurement, and contact lens application and removal training. They attended visits 1 week, 1 month, and 3 months after the initial dispensing visit. At each of these visits, the subjects underwent spherical over-refraction, keratometry, slitlamp examination, and standardized visual acuity measurement, and they completed surveys about contact lens wear.
The subjects received free eye care and contact lenses throughout the study, and they received a free 3-month supply of contact lenses at the end of the study. The subjects were fitted with 1-Day Acuvue contact lenses (Vistakon, Division of Johnson & Johnson Vision Care, Inc., Jacksonville, FL). The contact lens parameters available are listed in Table 2.
During the contact lens fitting, an 8.5-mm base curve contact lens with the spherical equivalent of the manifest refraction was placed on the right eye, and a 9.0-mm base curve contact lens with the spherical equivalent of the manifest refraction was placed on the left eye. The contact lens with the base curve that exhibited the most appropriate amount of movement and centration or the contact lens with the flatter base curve, if the movement and centration of the two contact lenses were similar, was dispensed.
The mean age of the children enrolled in the case series was 10.6 ± 1.5 years. The age of the subjects ranged from 8.4 to 12.9 years. Five (42%) of the 12 subjects were boys, and 10 (83%) of the 12 subjects were white.
The mean spherical equivalent prescription of the children’s glasses was −3.49 ± 2.03 D in the right eye and −3.53 ± 1.98 D in the left eye. The mean spherical equivalent prescription of the manifest refraction was −3.06 ± 2.22 D in the right eye and −3.01 ± 2.09 D in the left eye. On average, the prescription of the glasses was approximately 0.50 D more myopic than the result of the noncycloplegic manifest refraction performed at the baseline study visit. The subjects had little refractive astigmatism (Table 3).
In the right eye, the mean horizontal corneal power was 43.33 ± 1.83 D, and the mean vertical corneal power was 44.08 ± 1.83 D. In the left eye, the mean horizontal corneal power was 43.19 ± 1.90 D, and the mean vertical corneal power was 44.29 ± 1.94 D. According to Javal’s rule, we expected 0.38 D against-the-rule refractive astigmatism in the right eye and 0.43 D against-the-rule astigmatism in the left eye. The mean spherocylindrical refractions for the right and left eyes were −3.01 −0.10 × 091 and −2.98 −0.06 × 101, respectively. The expectations for refractive cylinder based on Javal’s rule were less than we measured, but they were against-the-rule as expected. None of the subjects had corneal staining or any other corneal findings before the contact lens fitting.
The mean contact lens power of the contact lens that was trial fitted was −3.02 ± 2.18 D in the right eye and −2.94 ± 2.09 D in the left eye. Only one patient accepted more than 0.25 D extra power (more minus or less minus) during the spherical over-refraction. That subject’s manifest refraction was −6.75 DS in the right eye and −6.75 −0.25 × 165 in the left eye. The subject accepted +0.75 D over the right eye and +0.50 D over the left eye, which corresponded to the correction for vertex distance.
The mean logarithm of the minimum angle of resolution visual acuity with the contact lenses to be dispensed on the eyes was +0.04 ± 0.10 (20/22 Snellen equivalent) in the right eye, +0.04 ± 0.12 (20/22 Snellen equivalent) in the left eye, and +0.02 ± 0.09 (20/21 Snellen equivalent) with both eyes.
The 9.0-mm base curve contact lens was dispensed to eight (67%) of the subjects. The median power of the contact lenses that was dispensed was −2.00 D in the right eye (range, −1.00 to −7.00 D) and −2.00 D in the left eye (range, −1.00 to −6.50 D), which was the same as the median power of the contact lenses that were originally trial fitted on the subjects.
The 1-week visit took place 8.3 ± 2.9 days after the dispensing. The 1-month and the 3-month visits took place 29.9 ± 5.6 days and 91.6 ± 11.9 days after the dispensing visit, respectively. Eleven of the subjects were examined at 1 week; 9 subjects were examined at 1 month; and 10 subjects were examined at 3 months. One subject decided that she did not want to wear contact lenses before she attended the 1-week visit because she did not like to apply and remove the contact lenses. One subject moved from the area after attending the 1-month visit. He continued to wear contact lenses, but he did not participate in the study. Ten (83%) of the 12 original subjects wore their contact lenses for the entire 3-month study.
At each of the three follow-up visits, the binocular visual acuity was close to 20/20, and the monocular logarithm of the minimum angle of resolution visual acuity ranged from +0.09 (20/24) to +0.02 (20/21) at the visits (Table 4). None of the subjects exhibited conjunctival injection, corneal infiltrates, striae, microcysts, or corneal staining at any of the follow-up visits.
By the end of the study, we switched one subject from the flat base curve to the steep base curve, and we switched one subject from the steep base curve to the flat base curve. We did not change the base curve in any of the other subjects who completed the study. Between the dispensing visit and the 3-month visit, we increased the power of the contact lens for 9 of the 20 eyes. Of those nine eyes, seven of them increased by −0.25 D. For the 10 subjects who completed the study, the power of the contact lenses that were dispensed at the baseline visit (mean, −1.58 D in the right eye and −1.60 D in the left eye) did not differ in power from the power of the contact lenses that were dispensed at the 3-month visit (mean, −1.76 D in the right eye and −2.00 D in the left eye) for either eye (Wilcoxon matched-pairs signed rank test, p = 0.05 for the right eye and p = 0.04 for the left eye). No contact lenses were ordered with a less minus power than was originally dispensed.
At the 1-week visit, the mean wearing time was 68.9 ± 20.2 h/week (range, 36 to 95 h/week). At the 1-month visit, the mean wearing time was 85.7 ± 8.7 h/week (range, 67–95 h/week), and at the 3-month visit, the mean wearing time was 76.7 ± 20.8 h/week (range, 38–103 h/week). The mean daily wearing time at the 3-month visit was 11.1 ± 3.2 h/day.
At all visits except the 3-month visit, all subjects reported that their vision was “pretty good” or “perfect.” At the 3-month visit, one subject reported her vision was “okay.” All subjects but one reported that their eyes were “always comfortable” or “usually comfortable” at the 1-week and 1-month visit. One subject at each of those visits reported that his or her eyes were “usually uncomfortable.” At the 3-month visit, all subjects reported that their eyes were “always comfortable” or “usually comfortable.”
When asked about putting contact lenses on the eyes, 82% of the subjects said they “usually did not have a problem” at the 1-week visit. No subjects said they “never had a problem.” At the 3-month visit, 20% of the subjects “never had a problem,” and 60% of the subjects “usually did not have a problem” putting on their contact lenses. At the 1-week visit and the 1-month visit, 90% of the subjects “usually did not have a problem” or “never had a problem” taking out their contact lenses. At the 3-month visit, all subjects reported that they “usually did not have a problem” or “never had a problem” taking out their contact lenses. At all visits, approximately 90% of the subjects reported that they “usually did not have a problem” or “never had a problem” handling their contact lenses.
Children wear contact lenses for amblyopia therapy, 19 diplopia, 23 aphakia, 24 trauma, 27 light sensitivity, 26, 28 anisometropia, 25 and cosmesis, 25 but they are not routinely fitted with contact lenses for myopia. Many children are told by eye care practitioners that they cannot wear contact lenses until they are 12 or 13 years old. However, it has been shown that younger children are capable of rigid gas-permeable contact lens wear 8 or soft contact lens wear 9 for myopia.
The primary reason that eye care practitioners do not fit children younger than 12 or 13 years old is that they think the children are not responsible enough to care for contact lenses. They think that children may not be able to apply and remove their own contact lenses, that they may not remove their contact lenses before bedtime, and that they may not clean or disinfect their contact lenses.
Previous reports have shown that children can apply and remove contact lenses independent of parental supervision between the ages of 8 and 11 years. 8, 9 Some children younger than 8 years may also be able to handle the responsibility of contact lens care, but each case should be evaluated individually.
Children remove their contact lenses before going to bed most of the time, but they should be educated about what to do if they forget to remove their contact lenses and sleep in them overnight. They should be told to instill a drop of artificial tears in the eyes before removal of the contact lens if the contact lens feels like it is stuck on the eye.
Daily disposable contact lenses eliminate the need for cleaning and disinfecting contact lenses, so they should be strongly considered as a contact lens treatment option for children. However, children should be reminded to always wash their hands with soap and water before application or removal of the contact lenses, and they should be told to rinse their hands thoroughly after washing with soap.
Although extended-wear contact lenses also eliminate the need for cleaning and disinfection and are perceived as being more convenient than daily disposable contact lenses, 16 they may not be appropriate for children. Wearing daily disposable contact lenses forces a child to learn to apply and remove the contact lenses. Children may not get used to the application and removal of contact lenses if the contact lenses are worn for 30 days of continuous wear. Should a problem arise, such as a foreign body or substance in the eye, the child must be able to remove the contact lens because he or she may not have assistance nearby. Therefore, extended-wear contact lenses are not a recommended option for novice pediatric contact lens wearers.
A 1-year supply of daily disposable contact lenses costs more than a 1-year supply of 2-week disposable contact lenses and multipurpose solutions, 29 but many people may decide that the added convenience of daily disposable contact lenses is well worth the additional cost. When explaining the extra cost of convenience for daily disposable contact lenses, one doctor asks his patients, “How much does your cell phone cost each month?” 30 The point of the question is that we pay extra for convenience every day.
In a society that places a premium on convenience, daily disposable contact lenses account for less than 5% of the contact lens market in the United States. 31 The benefits of daily disposable contact lenses should be fully explained to the patient, and the patient should weigh the cost vs. convenience of the contact lenses and make the decision.
Parents should know that daily disposable contact lenses eliminate the need for cleaning and disinfecting and thereby improve compliance. They allow for extra lenses in case of loss or damage, and they provide ocular health and comfort benefits because new lenses are placed on the eye daily. We have shown that children are capable of wearing daily disposable contact lenses between the ages of 8 and 11 years old and that they are happy with the benefits of daily disposable contact lens wear.
This case series used one of three brands of daily disposable contact lenses that are currently available in the United States, so we cannot compare success with various brands nor can we report that children are capable of wearing all brands of daily disposable contact lenses. We also did not collect data on palpebral conjunctival findings (e.g., follicles and papillae) in a standardized manner or whether the children continued to wear daily disposable contact lenses after the investigation. We know that some of the children wore rigid or soft contact lenses before this investigation, but we did not specifically collect that data from the children or their parents, so we cannot comment on whether previous contact lens wear affected success with daily disposable contact lens wear.
Eight- to 11-year-old children are able to wear daily disposable contact lenses. Both base curves of the 1-Day Acuvue contact lenses are appropriate for children. Children may require frequent monitoring because of changes in refractive error. Children are able to apply and remove the contact lenses without much difficulty. Despite the higher cost of daily disposable contact lenses, the option should be presented to parents because of the added convenience and improved compliance with contact lens care.
Supported by a grant from Johnson & Johnson Vision Care, Inc.
1. Mokdad AH, Ford ES, Bowman BA, et al. Prevalence of obesity, diabetes, and obesity-related health risk factors, 2001. JAMA 2003; 289:76–9.
2. Sperduto RD, Seigel D, Roberts J, Rowland M. Prevalence of myopia in the United States. Arch Ophthalmol 1983;101:405–7.
3. Blum HL. Vision Screening for Elementary Schools: The Orinda Study. Berkeley: University of California Press, 1959.
4. Goss DA. Cessation age of childhood myopia progression. Ophthalmic Physiol Opt 1987;7:195–7.
5. Duffey RJ, Leaming D. US trends in refractive surgery: 2002 ISRS survey. J Refract Surg 2003;19:357–63.
6. Allemann N, Chamon W, Tanaka HM, Mori ES, Campos M, Schor P, Baikoff G. Myopic angle-supported intraocular lenses: two-year follow-up. Ophthalmology 2000;107:1549–54.
7. Burris TE, Ayer CT, Evensen DA, Davenport JM. Effects of intrastromal corneal ring size and thickness on corneal flattening in human eyes. Refract Corneal Surg 1991;7:46–50.
8. Walline JJ, Mutti DO, Jones LA, Rah MJ, Nichols KK, Watson R, Zadnik K. The contact lens and myopia progression (CLAMP) study: design and baseline data. Optom Vis Sci 2001;78:223–33.
9. Horner DG, Soni PS, Salmon TO, Swartz TS. Myopia progression in adolescent wearers of soft contact lenses and spectacles. Optom Vis Sci 1999;76:474–9.
10. Binder PS. Myopic extended wear with the Hydrocurve II soft contact lens. Ophthalmology 1983;90:623–6.
11. Malet F, Schnider CM. Influence of replacement schedule and care regimen on patient comfort and satisfaction with daily wear frequent-replacement contact lenses. CLAO J 2002;28:124–7.
12. Fan L, Jun J, Jia Q, Wangqing J, Xinjie M, Yi S. Clinical study of orthokeratology in young myopic adolescents. Int Contact Lens Clin 1999;26:113–6.
13. Bailey MD, Walline JJ, Mitchell GL, Zadnik K. Visual acuity in contact lens wearers. Optom Vis Sci 2001;78:726–31.
14. Suchecki JK, Ehlers WH, Donshik PC. A comparison of contact lens-related complications in various daily wear modalities. CLAO J 2000;26:204–13.
15. Hamano H, Watanabe K, Hamano T, Mitsunaga S, Kotani S, Okada A. A study of the complications induced by conventional and disposable contact lenses. CLAO J 1994;20:103–8.
16. Nichols JJ, Mitchell GL, Zadnik K. Daily disposable vs. disposable extended wear: a contact lens clinical trial. Optom Vis Sci 2000;77: 637–47.
17. Nason RJ, Boshnick EL, Cannon WM, Dubow BW, Freeman MI, Kame RT, Lanier JC, Jr., Lopanik RW, Quinn TG, Jr., Rigel LE, et al. Multisite comparison of contact lens modalities. Daily disposable wear vs. conventional daily wear in successful contact lens wearers. J Am Optom Assoc 1994;65:774–80.
18. Snyder C, Hammack GG. Daily disposed hydrogel lenses—a comparison with biweekly replacement. J Am Optom Assoc 1994;65:164–8.
19. Joslin CE, McMahon TT, Kaufman LM. The effectiveness of occluder contact lenses in improving occlusion compliance in patients that have failed traditional occlusion therapy. Optom Vis Sci 2002;79:376–80.
20. Chia A, Johnson K, Martin F. Use of contact lenses to correct aphakia in children. Clin Exp Ophthalmol 2002;30:252–5.
21. Khoo CY, Chong J, Rajan U. A 3-year study on the effect of RGP contact lenses on myopic children. Singapore Med J 1999;40:230–7.
22. Perrigin J, Perrigin D, Quintero S, Grosvenor T. Siliconeacrylate contact lenses for myopia control: 3-year results. Optom Vis Sci 1990;67:764–9.
23. Burger DS, London R. Soft opaque contact lenses in binocular vision problems. J Am Optom Assoc 1993;64:176–80.
24. Moore BD. Pediatric aphakic contact lens wear: rates of successful wear. J Pediatr Ophthalmol Strabismus 1993;30:253–8.
25. Jurkus JM. Contact lenses for children. Optom Clin 1996;5:91–104.
26. Rakow PL. Making miracles with prosthetic soft lenses. J Ophthalmic Nurs Technol 1999;18:120–2.
27. Shaughnessy MP, Ellis FJ, Jeffery AR, Szczotka L. Rigid gas-permeable contact lenses are a safe and effective means of treating refractive abnormalities in the pediatric population. CLAO J 2001; 27:195–201.
28. Schiefer U, Kurtenbach A, Braun E, Kraus W, Zrenner E. Centrally tinted contact lenses. A useful visual aid for patients with achromatopsia. Ger J Ophthalmol 1995;4:52–6.
29. Ohio State University College of Optometry Pricing Guide. June 2003. Columbus: The Ohio State University, 2003.
30. Barr JA. Benefits of daily disposable contact lenses. Contact Lens Spect 2003;18:36–40.
31. Morgan PB, Efron NE, Woods CA, Jones D, Tranoudis Y, van der Worp E, Helland M, Hong AYC, Barr JT, Bailey GN. International Contact Lens Prescribing 2002. Contact Lens Spect 2003;18:40–3.