PEDIATRIC PEARLS
Educational Objectives
| The goal of this program is to improve the management of vision problems in children. After hearing and assimilating
this program, the clinician will be better able to:
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 | 1. Describe benefits of screening and therapy for vision problems in preschool children and recognize risk factors
for amblyopia.
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| 2. Differentiate among technologies now available for screening vision in preschool children.
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| 3. Evaluate the data from model vision screening programs.
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| 4. Diagnose and prescribe spectacles and bifocals for children with disorders such as myopia, hyperopia, and accommodative
esotropia.
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| 5. Identify pediatric candidates for treatment with contact lenses and choose the optimal type of lens.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning
committee to disclose relevant financial relationships within the past 12 months that might create any personal conflicts of interest.
Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary
business or commercial interest. For this program, Dr. Donahue disclosed a consulting relationship with Diopsys. Dr.
Schoeck and the planning committee reported nothing to disclose.
Acknowledgements
Dr. Donahue’s lectures were recorded at 2008 Ophthalmology Symposium: Pediatric Ophthalmology, held June 7, 2008,
in Universal City, CA, sponsored by the Southern California Permanente Medical Group. Dr. Schoeck’s lecture was
recorded at Update for the Comprehensive Ophthalmologist 2008: 26th Annual Meeting, held May 16, 2008, in Cleveland,
OH, sponsored by University Hospitals Case Medical Center, Case Western Reserve University School of Medicine.
The Audio-Digest Foundation thanks the speakers and the sponsors for their cooperation in the production of
this program.
| VISION SCREENING IN CHILDREN —Sean P. Donahue, MD, PhD, Professor of Ophthalmology, Pediatrics, and Neurology,
Vanderbilt University Medical Center, and Chief, Pediatric Ophthalmology Service, Department of Ophthalmology
and Visual Science, Tennessee Lions Eye Center, Nashville, TN
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| Preschool vision screening: performed by pediatrician who refers patient; first study—screening caused 10-fold drop
in risk for significant amblyopia; ≈50% of children with amblyopia in study had visual acuity (VA) of 20/30 or better;
second study—screened group had 30% higher risk for amblyopia, compared to that of unscreened group; only 0.1% of
screened children had severe loss of vision (VA of 20/60 or worse), compared to 1.5% to 2% of unscreened; third study—
compared intensive annual or biannual screening to single screening at 3 yr of age; found intensive screening provided
60% reduction in significant amblyopia at 7.5 yr
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| Efficacy of therapy: first study—screened and referred children for therapy; 1 yr later, only 1 of 18 children who did
not comply with therapy showed spontaneous improvement (amblyopia deteriorated or remained same in 17 of 18); 3
children at risk developed amblyopia because of noncompliance; second study—>1% of patients with amblyopia in one
eye lost vision in second eye; 66% of these could not remain employed
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| New technologies: detect factors that cause amblyopia (ie, amblyogenic or amblyopic factors), but do not detect amblyopia
itself; 2 types of technologies (ie, off-axis photoscreeners and autorefractors)
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| Amblyogenic risk factors: high levels of refractive errors (especially anisometropia), hyperopia, bilateral astigmatism
(can also cause strabismus), and media opacity; according to consensus statement from American Association for Pediatric
Ophthalmology and Strabismus (AAPOS), threshold levels for risk factors include anisometropia >1.50 diopters
(D); hyperopia >3.00 D; myopia >3.00 D; media opacity; astigmatism >1.50 D
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| Off-axis photoscreeners: in healthy emmetropic eye, flash image not visible through pupil; in nonemmetropic eye (eg, hyperopic)
image appears as crescent; similar procedure detects myopia and strabismus
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| MTI PhotoScreener: first case—hyperopic child; image showed crescent, then flash rotated to vertical to detect refractive
error in 2 principal meridians; second case—child with emmetropia in one eye, but cataract in second eye caused
inward deviation and strabismus; Brückner test showed light reflex deviated temporally, indicating eye deviated nasally;
cataract detected as media opacity blocking Brückner reflex
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| Preschool vision screening: model program—screened >200,000 children (97%) <5 yr of age; referred 4.5% to local optometrists
or ophthalmologists, and 75% of referred patients satisfied criteria in AAPOS guidelines for vision problem;
expanded program—includes 13 programs worldwide and has screened >750,000 children; referred 6%, with follow-up
available for 50%; found positive predictive value (PPV) 68%
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| i-Screen: similar to MTI but with digital camera so possible to send images over Internet for reading and interpretation;
results available next day
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| PlusoptiX: recently marketed instrument
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| Autorefractors: estimate refractive error using wave-front analysis; do not analyze for or detect strabismus
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| Nikon Retinomax and Welch Allyn SureSight: provide printout of refractive error and note whether it exceeds preprogrammed
referral criteria; less expensive than photoscreening; Vision in Preschoolers (VIP) Study suggests autorefractor
possibly more accurate than photoscreening; does not detect strabismus directly, but relies on higher refractive error
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| VIP Study: 3-phase study compared screening instruments to cycloplegic refraction (gold standard); phase 1 found autorefractors
more sensitive than all other tests (including acuity test with Lea symbols); possibly also more effective
than photoscreeners (controversial)
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| Diopsys: screening technology that uses visual evoked potentials and responses; amblyopic eyes produce lower amplitude
and threshold for visual evoked response than fellow eyes; robust widely reimbursed electrophysiologic test
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| INDICATIONS FOR PRESCRIBING GLASSES AND BIFOCALS —Dr. Donahue
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| Symptomatic patients: myopia—distance acuity less necessary in children than in adults; myopia of -1.00 D in child 3
yr of age different treatment situation from patient at 14 yr of age with myopia of -2.00 D; hyperopia—treat accommodative
esotropia to straighten eyes and develop binocular vision; treating accommodative strabismus decreases risk
of needing surgery and developing amblyopia; prospective study—among children with >+3.50 D of hyperopia,
treated group had 4-fold higher risk of developing strabismus or amblyopia than general population, but untreated children
had 13-fold higher risk; crossing—in infants, prescribe spectacles if >+2.50 D, or surgery if <2.50 D; in older
child with >+2.00 D, treatment depends on accommodative convergence-accommodation (AC/A) ratio and near-distance
disparity; ie, if no difference observed between near and distance measurements, do not prescribe unless hyperopia
higher
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| Prescribing bifocals for accommodative esotropia: appropriate when large difference exists between near vision and distance
vision, but must be in monofixation range in distance; surgery required for >8 prism diopters (PD) of esotropia in
distance (prism adaptation); for child with <8 PD in distance vision but out of monofixation range at near vision (ie,
>10 PD), +3.00 D split-pupil bifocal needed to collapse near deviation; speaker does not prescribe progressive bifocals
for young children because they do not get down into +3.00 D until bottom of segment; therefore, cannot collapse near-
distance disparity; speaker occasionally uses progressive bifocals in children at 8 to 9 yr of age who may be at +2.00 D
and weaning out of bifocals
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| Prophylactic bifocals: consider bifocals as first glasses for child with accommodative strabismus and high AC/A ratio
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| Asymptomatic hyperopia: reasons to treat—infantile and accommodative esotropia or family history of strabismus;
threshold of +3.00 D or +2.50 D appropriate for prescribing spectacles; questionable cases—speaker does not favor
prescribing for patients with poor accommodative effort or accommodative insufficiency (unless Down syndrome
present and child hypoaccommodates); use strong accommodative target; obvious in children who play video games;
study—no correlation between acuity, refraction, and academic performance among 2000 children with hyperopia
(many had low level of hyperopia); reasons not to treat—unknown whether treatment of asymptomatic patients with
hyperopia decreases natural emmetropization in adulthood; expense of spectacles; inconvenience to parents; benefit
not apparent to parents
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| Evidence to guide prescribing: study—evaluated accommodative ability of 4000 healthy children; found normal child at
8 yr of age has 14 D of accommodative ability (range, 12-16 D); prescribing decision—consider that 7.00 D accommodation
needed to accommodate to level of one-third meter with +4.00 D hyperopia, because ability to focus 4.00 D
needed to achieve emmetropia and additional 3.00 D needed to achieve near working distance of 33 cm; to determine
maximum tolerable amount of uncorrected hyperopia in child who has working distance of 33 cm when reading and
needs one-half of accommodation in reserve, assume 7.00 D can be used and 3.00 D needed to read at 33 cm; child can
tolerate up to +4.00 D hyperopia without treatment; first study—conducted to determine definition of hyperopia; evaluated
several hundred children and found mean hyperopia of 1.40 D, with 95% at <3.25 D; second study—evaluated
refractive errors in children 5 to 15 yr of age in 3 countries; found most children in Nepal had 2.00 D, most in Chile had
2.50 D, and most in China had 3.00 to 3.50 D; among 21 children with >+4.00 D hyperopia, all had uncorrected VA of
20/40 or better; follow-up study found little degradation of VA until hyperopia reached +3.50 to +4.00 D
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| Surveys of current practice: survey of 212 optometrists and 102 ophthalmologists found 33% and 5%, respectively, would
prescribe for asymptomatic child at 6 yr of age with +3.00 to +4.00 D hyperopia; for child at 2 yr of age, most would
not prescribe until hyperopia reached +5.00 D; second survey— majority of AAPOS members who responded prescribed
at level of hyperopia of +4.00 to +5.00 D in asymptomatic children ≤6 yr of age
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| Preferred practice patterns from American Academy of Ophthalmology: guidelines mandate cycloplegia with cyclopentolate
during examination of children; recommend prescribing at +4.50 D for children at 3 yr of age; for children at 4 yr of
age, prescribe to improve VA or alleviate asthenopia; AAPOS Vision Screening Committee recommends prescribing for
hyperopia >+3.50 D, as did VIP study; speaker recommends average threshold of +3.50 D (raises to +4.00 to +5.00 D for
younger children, and lowers to +2.00 to +3.00 D for those with family history of strabismus or Down syndrome); measure
accommodative strabismus and treat with full cycloplegic refraction; for patients with high hyperopia but no strabismus,
undercorrect by 1.50 D
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| Adherence to guidelines: first study—possibly 35% of children wearing glasses did not need them; recent screening
program—screened 100,000 children and referred 3600; 2700 referred children met AAPOS criteria for true vision
problem, 890 did not (false positives); in cases where there was no other pathology and which did not meet AAPOS
criteria, optometrists recommended glasses 36% of time, ophthalmologists recommended glasses 11% of time, and pediatric
ophthalmologists recommended glasses 1.8% of time; 15 children <6 yr of age received glasses for <1.00 D hyperopia;
rate not influenced by clinician’s level of experience; 18% rate of prescription error amounts to $135 million
spent annually (direct cost) on unneeded glasses in United States
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| CONTACTS AND KIDS: A WINNING COMBINATION —Sara E. Schoeck, OD, Optometrist and Senior Instructor, University
Hospitals Case Medical Center, Rainbow Babies and Children’s Hospital, Cleveland, OH
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| Contact Lenses in Pediatrics Study: compared fitting of elective contact lenses (CL) and follow-up for children at 8
to 12 and 13 to 17 yr of age; found age alone insufficient criterion upon which to base CL recommendation; both groups
adjusted similarly and neither experienced problems
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| Factors in prescribing elective CL
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| Readiness and motivation: assess hygiene to determine child’s ability to comply with CL care protocols; athletic children
generally motivated and able to insert and remove CL; anecdotal evidence suggests girls may be more motivated and
able to wear CL; evaluate whether CL serve visual needs of patient
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| Appropriate lens: speaker favors silicone hydrogel lens because of high permeability to oxygen; she often recommends
UV-protective CL, and always recommends sunglasses; speaker never prescribes extended-wear CL because of risk for
bacterial keratitis and corneal ulcers; rigid gas-permeable (RGP) CL easy to care for, durable, and may potentially slow
progression of myopia
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| Replacement schedule and wear time: monthly or daily disposable CL better for compliance; daily disposables eliminate
care system, avoid infections by Fusarium and Acanthamoeba associated with multipurpose solutions (MPS), and appropriate
for children with allergies; spherical, toric, and multifocal lenses available, but only 7% of patients in United
States wear daily disposable CL, compared to up to 45% elsewhere
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| Appropriate involvement by parents: patients should care for CL independently
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| Common indications in children: monocular or bilateral aphakia, irregular astigmatism, high myopia, high astigmatism,
uncorrected hyperopia associated with esotropia, and anisometropia
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| Soft CL for aphakia and high hyperopia: silicone elastomer (eg, Bausch & Lomb SilSoft) for infants; range of powers; 2
diameters; speaker encourages parents to remove CL every 3 to 4 nights; advantages—high oxygen permeability, performance,
and improved cosmesis over spectacles; limitations—drying, accumulation of deposits (eg, lipids) on surface,
and need for more frequent follow-up because of potential for infection or inflammation; fitting—use spectacle
prescription from surgeon (after cataract surgery), correct for vertex distance, and apply necessary overcorrection for
near vision
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| Custom silicone hydrogel: features—high oxygen permeability, surface that resists deposits, and better movement
and tear exchange; only available as daily wear lens; limited powers
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| Anisometropia and convergence excess: treat with spherical silicone hydrogel or silicone hydrogel multifocals (eg, PureVision
Multifocal), respectively
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| RGP CL: Contact Lenses and Myopia (CLAMP) Study—found 80% of young patients adapted to RGPs successfully;
alignment- fit RGPs flattened corneal curvature by 0.50 D in 2 mo; did not slow axial growth of eyes, so no permanent
effect on slowing myopia; in infants—eg, for aphakia; RGPs approved for extended wear; require more skill to fit;
possible to do in hospital under anesthesia in operating room using spectacle prescription from surgeon, then correct
for vertex distance and add overcorrection for near vision
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Suggested Reading
Braveman R: Diagnosis and treatment of refractive errors in the pediatric population. Curr Opin Oththalmol 18:379,
2007; Brook I: Ocular infections due to anaerobic bacteria in children. J Pediatr Ophthalmol Strabismus 45:78, 2008;
Campos EC: Why do the eyes cross? A review and discussion of the nature and origin of essential infantile esoptroia, microstrabismus,
accommodative esotropia, and acute comitant esotropia. J AAPOS Jun 10[Epub ahead of print], 2008; Carlton
J et al: The clinical effectiveness and cost-effectiveness of screening programmes for amblyopia and strabismus in
children up to the age of 4 to 5 years: a systematic review and economic evaluation. Health Technol Assess 12:1, 2008;
Cotter SA: Management of childhood hyperopia: a pediatric optometrist’s perspective. Optom Vis Sci 84:103, 2007;
Cotter SA et al: Treatment of strabismic amblyopia with refractive correction. Am J Ophthalmol 143:1060, 2007;
Donahue SP: Clinical practice. Pediatric strabismus. N Engl J Med 356:1040, 2007; Duncan PM et al: Bright Futures:
the screening table recommendations. Pediatr Ann 37:152, 2008; Kemper AR: Corrective lens wear among adolescents:
findings from the National Health and Nutrition Examination Survey. J Pediatr Ophthalmol Strabismus 44:256,
2007; Kirk VG et al: Preverbal photoscreening for amblyogenic factors and outcomes in amblyopia treatment: early objective
screening and visual acuities. Arch Ophthalmol 126:489, 2008; Mahoney BG: Common forms of childhood strabismus
in an incidence cohort. Am J Ophthalmol 144:465, 2007; Rogers DL et al: Comparison of the MTI
Photoscreener and the Welch-Allyn SureSight autorefractor in a tertiary care center. J AAPOS 12:77, 2008; Saltarelli
DP: Hyper oxygen-permeable rigid contact lenses as an alternative for the treatment of pediatric aphakia. Eye Contac Lens
34:84, 2008; Shah S et al: Prevalence of amblyogenic risk factors in siblings of patients with accommodative esotropia. J
AAPOS Jun 4 [Epub ahead of print], 2008; Tingley DH: Vision screening essentials: screening today for eye disorders in
the pediatric patient. Pediatr Rev 28:54, 2007; Vision in Preschoolers Study Group: Does assessing eye alignment
along with refractive error or visual acuity increase sensitivity for detection of strabismus in preschool vision screening? Invest
Ophthalmol Vis Sci 48:3115, 2007; Webber AL: Amblyopia treatment: an evidence-based approach to maximizing
treatment outcome. Clin Exp Optom 90:250, 2007; Williams C et al: Prevalence and risk factors for common vision
problems in children: data from the ALSPAC study. Br J Ophthalmol 92:959, 2008.
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