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It might come as a surprise to parents, but contact lenses are a mainstay of optical correction options for children with special refractive needs. For a myopic 10-year-old hockey player, contact lenses can solve the problem of eyeglasses that fog up during the game. For a preschooler with anisometropia, they can give the brain the two sharp images it needs to develop stereoacuity. And for tiny infants with aphakia after congenital cataract removal, they can bring the world into focus and encourage the visual system to mature normally.
Successful use of contact lenses in children doesn’t have to be difficult. A physician’s recommendations about the lenses best suited to a child’s age and needs, as well as the doctor’s skill in training parents to insert and remove an infant’s or a toddler’s lenses, can go a long way toward helping children benefit from contacts.
The Lenses: Recommended Uses
Several types of lens are available for pediatric patients. Each has its benefits, and the choice will depend on the individual child’s needs.
Silsoft lens. For aphakic infants who have not received an intraocular lens (IOL), the most widely used contact lens is Silsoft (Bausch + Lomb). It is an extremely soft, extended wear lens made from 100 percent silicone polymer, which is generally acknowledged to have the best oxygen permeability of any contact lens. Easy to fit and well tolerated, it comes in the high powers required for aphakia (from +7 D to +32 D), and the material resists absorption of topical ophthalmic drugs.
Rigid gas-permeable lenses. Some clinicians prefer to put aphakic children of any age, even infants, in contact lenses made from rigid gas-permeable (RGP) materials, both for their oxygen transmissibility and for the smaller steps in refractive power that they offer. “Silsoft lenses are easy to fit, so a lot of people use them. But currently they only come in 3-diopter increments for patients with hyperopia greater than 20 diopters—whereas with an RGP lens, you can be more precise in correcting the child’s refractive error,” said Amy K. Hutchinson, MD, associate professor of ophthalmology at Emory University. She noted that to prevent corneal erosions, RGP lenses must be fitted carefully by a well-experienced contact lens fitter.
Soft lenses. Conventional soft contact lenses usually are not used in young children because they are harder to handle and less suitable for extended wear due to their lower oxygen transmission than silicone or RPG materials. If a child does start to wear these lenses, close monitoring for hyperemia or other signs of ocular stress is recommended.
Silicone hydrogel soft lenses are a newer form of soft lens with higher oxygen transmission. If the child is prescribed a silicone hydrogel lens, care should be taken during the fitting process to avoid corneal erosions from a tight lens. A few studies have implicated erosions as a cofactor in microbial keratitis related to silicone hydrogel lenses—especially those used for extended wear.1
If the clinician has concerns about parental adherence to lens care guidelines, daily disposable lenses offer a possible solution independent of the child’s age. “Daily disposables are nice because the parents can just put them on the child’s eye once and then throw them away at the end of the day,” Dr. Hutchinson said. She noted that disposables also simplify lens care for children who have become old enough to insert and care for contact lenses themselves.
Scleral lenses. “Some of the most helpful new things for tough cases are the latest scleral or hybrid contact lenses,” said David G. Hunter, MD, PhD, ophthalmologist-in-chief at Children’s Hospital Boston and professor of ophthalmology at Harvard University. These large-diameter contact lenses, which do not touch the cornea, can help children with a broad range of refractive and ocular surface disorders, including congenital corneal anesthesia syndromes, Stevens-Johnson syndrome and corneal scarring after trauma. (For more information about these lenses, see the January feature story at www.eyenetmagazine.org.)
Orthokeratology lenses. Parents and pediatricians sometimes ask about these overnight contact lenses for flattening myopic corneas. Research shows that the effects are temporary, and additional study is needed to determine whether there is an increased risk of infection and other complications when orthokeratology lenses are used at night.2
When to Use Contacts for Aphakia
Children who are born with cataracts or who develop them in infancy require refractive correction after their cloudy lens is removed. Which approach to use as primary therapy depends on the nature of the aphakia.
Bilateral aphakia. If IOLs are not implanted, contact lenses are the first choice for visual rehabilitation. Eyeglasses may be prescribed if lost lenses or parental difficulty with inserting and removing the lenses prevents success with this modality.
Unilateral aphakia. Recommended therapy for unilateral aphakia depends on whether the child is older or younger than age 2.
- Older than 2 years. Today, most children who undergo cataract removal after age 2 will emerge from surgery with an IOL in place.
If an IOL is not implanted, contact lenses are usually the first choice for visual rehabilitation. Drs. Hunter and Hutchinson agreed in principle that eyeglasses are a less desirable option for these children because the magnification effect from the spectacle lens interferes with development of binocularity.
- Ages 6 months to 2 years. Many surgeons prefer IOLs for children in this age group, but contact lenses remain an important therapeutic option, Dr. Hunter said. “In patients over age 6 months with unilateral cataracts, my preference is to place an intraocular lens at surgery. However, if a child is already aphakic, I will stay with contact lenses but move quickly to a secondary IOL if there is contact lens intolerance.”
- Ages 1 to 6 months. The ongoing Infant Aphakia Treatment Study has not yet determined the preferred method of optical correction for these infants, Dr. Hutchinson said. She is a coinvestigator in this multicenter trial, which randomized 114 infants to IOLs or contact lenses after cataract surgery. At age 1 year, the two groups had statistically equivalent visual outcomes. However, the greater incidence of complications requiring additional surgical interventions in the IOL group argues for continued caution; follow-up through age 5 is continuing.3
Fine-tuning with spectacles. Children who are aphakic or pseudophakic may also need to use spectacles, for example, to correct for astigmatism that IOLs or contact lenses do not address. It is essential that school-age children have a reading add to allow the child to focus at near.
In addition, some children with IOLs wear eyeglasses with low-power distance correction because their implants leave them with slight hyperopia. Dr. Hutchinson said she does this for two reasons. “I like these children to wear eyeglasses for safety,” she said. “Also, we know that the child’s eye will naturally undergo a myopic shift as it grows, so I prefer to initially undercorrect them. Then the residual refractive error can move toward emmetropia.”
Anisometropia and Amblyopia
In phakic children with amblyopia caused by severe anisometropia, strabismus or accommodative esotropia, eyeglasses are usually the first form of refractive therapy offered along with eye patching. However, contact lenses can be helpful if spectacle therapy proves problematic.
“I am reluctant to prescribe contact lenses due to the increased risk of infection of the sound eye and the loss of the protective feature of the spectacles,” Dr. Hutchinson said. “However, in some cases if the child is terribly bothered by the appearance of the ‘unbalanced’ spectacles, I will consider correcting the highly ametropic eye with a contact lens, and having the patient wear a thin pair of shatter-resistant spectacles just for protection.”
Dr. Hunter said he rarely uses contact lenses in anisometropic phakic children in the amblyopic age group. “The only time we’ll use a contact lens for these amblyopia cases is when there’s a real problem with using glasses,” he said. “There’s a magnification difference between the two eyes. Contact lenses minimize this difference and make the therapy more tolerable for the child. But they are not necessarily essential.”
Occlusion therapy. Infrequently, if occlusion therapy with eye patching and atropine fail to reverse amblyopia, an opaque contact lens can be used instead to suppress images from the dominant eye.
Last resort? A phakic IOL. Since 2008, a handful of research papers have proposed rescuing the vision of extremely treatment-resistant amblyopic children by implanting an anterior chamber “iris-claw” phakic IOL (Verisyse, AMO). Because this puts endothelial cells at risk, surgeons who have used this approach warn that it should be reserved for special-needs cases in which there is severe vision loss from intractable noncompliance with spectacle, contact lens and occlusion therapy.4-6
“The ideal form of treatment for high refractive errors should be medical contact lenses. But in stubbornly noncompliant patients, a phakic IOL is a welcome alternative to keep these children from falling through the cracks,” said Amir Pirouzian, MD, author of a report on phakic implants in seven children.4 Dr. Pirouzian is a cornea/external disease and refractive fellow and clinical instructor at the Gavin Herbert Eye Institute, University of California, Irvine, and has also completed a fellowship in pediatric ophthalmology at UCLA.
The children on whom Dr. Pirouzian operated were 5 to 11 years of age at the time of surgery, with preoperative corrected distance visual acuity (CDVA) in the affected eye of 20/200, 20/400, or 20/1000 or worse. Three years after surgery, five of the eyes had CDVA of 20/40 or better, and the other two measured 20/50 and 20/60.
At first, parents of young children who require optical correction are amazed that contact lenses are an option—and then they become apprehensive about the logistics. “When you first introduce the idea, parents are surprised that even infants wear contact lenses,” Dr. Hutchinson said. “But a large number of aphakic patients can be successful with contact lens therapy if you’re careful about screening families and if you instruct the parents well.”
Wearing time. For aphakic infants in Silsoft contact lenses, both Drs. Hutchinson and Hunter recommend that parents let the infants wear the lenses for as long as a week, 24 hours a day, before removing them for cleaning.
When possible, Dr. Hutchinson prefers to put aphakic infants and children into RGP lenses, which must be taken out and cleaned nightly.
If an older child wears disposable soft contact lenses, she recommends against sleeping in the lenses, even if they are labeled for extended wear. “I don’t like them to leave contact lenses in overnight. I’m concerned about oxygen deprivation to the cornea overnight through a closed eyelid,” she said.
Infections. The risk of contact lens–related corneal infections can be minimal if parents care for the lenses properly. In the contact lens group of the Infant Aphakia trial, 1 of 57 babies (less than 2 percent) developed presumed bacterial keratitis.3
Cost. Some families find the ongoing costs of contact lenses to be a barrier to treatment compliance. For instance, special silicone contact lenses for infant aphakia cost from $300 to $700 per pair, depending on the refractive power and level of customization. Lens loss is common, and lenses also must be replaced as the child’s eye grows and refraction changes.
Training. Even if a family can afford the costs, this modality will fail if a contact lens technician does not help relieve parents’ anxiety by training them to insert and remove the lenses, Dr. Hunter said. His practice even has a secret weapon: a six-minute YouTube video, made by the mother of two of his patients. The video, which has been viewed more than 42,000 times, shows the mother calmly popping contact lenses in and out of her baby’s eyes. She also urges parents in a web post to “hang in there. … Be patient and believe that you can do it.”
Said Dr. Hunter: “While it can be very stressful for the family at first, most parents become quite skilled at inserting and removing lenses—it becomes a matter of routine. It becomes more like changing a diaper than this awful event that everyone dreads.”
Dr. Hunter founded and owns stock in REBIScan, which is developing a device for pediatric vision screening. Drs. Hutchinson and Pirouzian report no financial conflicts.
1 Willcox MD et al. Eye Contact Lens. 2010;36(6):340-345.
2 Van Meter WS et al. Ophthalmology. 2008;115(12):2301-2313.
3 The Infant Aphakia Treatment Study Group. Arch Ophthalmol. 2010;128(7):810-818.
4 Pirouzian A, Ip KC. J Cataract Refract Surg. 2010;36(9):1486-1493.
5 Trivedi RH, Wilson ME. J Cataract Refract Surg. 2010;36(8):1432-1434.
6 Tychsen L et al. J AAPOS. 2008;12(3):282-289.
Contact Lenses in Older Children
At around age 10, children with normal levels of refractive error and a distaste for wearing eyeglasses become interested in contact lenses, said Dr. Hunter. “This is either because of appearance or because of sports. I’ve had several 8- or 9-year-old hockey players, for instance, who came in asking for contact lenses because their glasses fog up while they’re playing.”
Some clinicians set rigid age limits for contact lenses (usually about 10 or 11 years), and others prefer a case-by-case evaluation of the child’s maturity and responsibility. “I insist on the child being a participant in putting the contact lenses in and taking care of them,” Dr. Hunter said. “If their room is always a mess, then that is probably a sign that they’re not going to be fastidious about taking care of their contact lenses. But if they are responsible kids who take care of their own hygiene, then we say yes. There’s no reason that we shouldn’t put them in contact lenses just because of their age,” he said.
Dr. Hutchinson agreed. “I have one little girl with accommodative esotropia who began wearing contact lenses when she was 4 years old. Her mom is a contact lens tech, so they were comfortable with the idea. The girl has been in contact lenses for six years now and is doing well.”