Contact Lenses in Children: Getting It Right—Lens, Age and Need Clinical Update

Clinical Update
PE DI AT R IC S
Contact Lenses in Children:
Getting It Right—Lens, Age and Need
by linda roach, contributing writer
interviewing david g. hunter, md, phd, amy k. hutchinson, md, and amir pirouzian, md
© 2 012 b u d d y m . r u s s e l l , f c l s a , c o m t, e m o r y e y e c e n t e r
I
t 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
C o n t a c t L e n s f o r an A p hak i c I n f an t
1
2
© 2012 Buddy M. Russell, FCLSA, COMT,
Emory Eye Center
(1) Instillation of fluorescein to evaluate lens fit in a 2-month-old boy. (2) An
RGP contact lens is gently inserted into his aphakic eye.
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 gaspermeable (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
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Pediatr ics
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
eye­g lasses 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,
C o n t a c t L e n s e s in O l d e r Chil dr e n
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.”
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m a r c h
2 0 1 2
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; followup 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 hyper­
opia. 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
susan purcell
Pediatr ics
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 shatterresistant 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.
Parental Issues
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 over­
night 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
HOW TO. Dr. Hunter refers parents to a
YouTube demonstration of contact lens
insertion in both an infant and a small
child. View it at www.youtube.com/
watch?v=sxHnoJP4t7I.
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):282289.
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