PROBLEMS IN PEDIATRIC PATIENTS
From Update for the Comprehensive Ophthalmologist, presented May 16, 2008, by Case Western Reserve University School
of Medicine
Educational Objectives
| The goal of this program is to improve the management of cataracts, glaucoma, and ocular trauma in children. After
hearing and assimilating this program, the clinician will be better able to:
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 | 1. Recognize the special considerations in pediatric cataract surgery.
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| 2. Review the advantages and disadvantages of contact lens, compared to intraocular lens, correction of unilateral
aphakia.
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| 3. Recognize the clinical features of pediatric glaucoma.
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| 4. Choose the appropriate surgical intervention for pediatric glaucoma.
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| 5. Describe the mechanisms of childhood ocular injuries.
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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, the faculty and planning committee reported nothing to disclose.
Acknowledgements
Drs. Lambert and Orge were recorded at Update for the Comprehensive Ophthalmologist 2008 26th Annual Meeting, held
May 16, 2008, in Cleveland, OH, and sponsored by Case Western Reserve University School of Medicine. The Audio-Digest
Foundation thanks the speakers and Case Western Reserve University School of Medicine for their cooperation
in the production of this program.
| CATARACT SURGERY IN CHILDREN —Scott R. Lambert, MD, Howard Dobbs Professor of Ophthalmology and Pediatrics,
Emory University School of Medicine, Atlanta, GA
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| Epidemiology: cataracts—not common in children; cause of blindness, particularly in developing countries; occur in 2
to 3 of every 10,000 live births (≈50% unilateral)
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| Cataract surgery: special considerations in children include infection, preoperative antibiotics and nonsteroidal anti-inflammatory
drugs, changes in axial length, and greater inflammatory response; latent period for unilateral cataract—
noted in 1996 paper by Birch and Stager; first 6 wk of life (associated with achieving best visual outcome); surgery no
longer done at 1 day of age; tendency to wait until infant 1 mo of age; 4 to 6 wk after birth optimal time for surgery; children
with bilateral cataracts, once they develop nystagmus, more likely to have poor visual outcome; at birth, average axial
length 17 mm; tremendous growth of eye in first 2 yr of life (average 22 mm); solution to undercorrect in first 5 yr of
life (≈40 diopters [D] in first year of life, then decreasing); some clinicians undercorrect until 10 to 12 yr of age; to prevent
postoperative inflammation—avoid iris prolapse or manipulation; heparin; topical corticosteroids; atropine; systemic
corticosteroids; complications often seen after surgery include visual axis opacities and glaucoma; opacification of posterior
capsule almost universal if left intact; for this reason, posterior capsulotomy with anterior vitrectomy performed; lens
reproliferation into visual axis also seen; high incidence of glaucoma, particularly if cataract surgery done during first
year of life (25% in some studies)
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| Optical rehabilitation: intraocular lenses (IOLs)—standard of care for children ≥1 yr of age; questionable whether
good idea in rapidly growing child and whether possible to predict best lens power; contact lenses (CLs)—standard of
care in infants; Silsoft (elastofilcon A) lenses used by most pediatric ophthalmologists because of ease of use and high
oxygen permeability (Dk) value; speaker uses rigid gas-permeable CLs; aphakic glasses—preferred by some parents;
cosmetically undesirable and heavy; secondary IOLs—first choice capsular fixation after opening Soemmering’s ring;
second choice sulcus fixation supported by capsular remnants; anterior chamber IOLs and suture-fixated IOLs should be
avoided
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| CL correction of unilateral aphakia: pros—power of lens easily changed as eye grows; secondary IOL implanted
when child older; cons—frequently lost and possible delay in replacement; ongoing maintenance takes time and stressful
for parents and child
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| IOL correction of unilateral aphakia: pros—closely approximates optics of crystalline lens; full-time partial optical
correction guaranteed; cons—surgery more difficult; concern about safety; higher reoperation rate; in most cases, requires
additional correction
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| 2001 American Association for Pediatric Ophthalmology and Strabismus (AAPOS) survey: asked
about concerns with use of CLs vs IOLs in child with congenital cataract; with CLs –poor compliance; high lens loss rate;
cost; with IOLs—poor predictability of refractive changes; high incidence of postoperative complications; strong preference
for CLs
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| Clinical trial: multicenter (12), randomized; eligibility criteria—visually significant cataract in one eye; age 1 mo to 7
mo at time of surgery; willingness to be randomized to either treatment; exclusion criteria—acquired cataract; corneal
diameter <9 mm; elevated intraocular pressure (IOP); severe persistent fatal vasculature (PFV) defined as stretching of
ciliary processes; uveitis; preterm delivery; retinal disease; ocular disease in fellow eye; mental condition that would interfere
with visual acuity (VA) testing at 4.5 yr of age; parent’s refusal of randomization; inability to comply with regular
follow-ups (every 3 mo until 5 yr of age); 2 groups—CL group had lensectomy and CL correction; IOL group had cataract
extraction (CE), primary IOL implantation, primary posterior capsulotomy through pars plana with vitrectomy, and
spectacle overcorrection as needed; in CL group—participants received Silsoft or rigid gas permeable CL; overcorrected
by 2 D until 2 yr of age, then corrected for emmetropia, and bifocals prescribed; in IOL group—Acrysof SN60 lens used;
when 4 to 6 wk of age, targeted for 8 D undercorrection; at 7 to 28 wk of age, targeted for 6 D undercorrection, using
Holladay formula; patching regimen—1 hr daily per month of age for first 8 mo of age, then 50% of waking hours past 8
mo of age; most difficult for parents; primary hypothesis—at 4.5 yr of age, optotype acuity in affected eyes treated with
IOL ≈2 lines better than in children in CL group; primary outcome—tested by examiner traveling to different centers;
first testing done at 12 mo of age using preferential looking and Teller acuity cards; second testing at 4.5 yr of age using
HOTV test; examination at 4.5 yr of age—includes testing for acuity using HOTV letters; stereoacuity evaluation; Child
Behavioral Checklist; Movement Assessment Battery for Children to test fine gross motor skills; tonometry; final assessment
at 5 yr of age—looks at ocular motility, axial length (to determine degree of undercorrection), and change in corneal
curvature; keratometry (K); tonometry; specular microscopy
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| Case 1: infant girl, 5 wk of age, with dense cataract in left eye (LE); underwent lensectomy; randomized to receive CL;
treated eye slightly shorter; keratometric (K) readings same in both eyes; power for emmetropia, 44 D; infant fitted with
Silsoft CL; adequate patching performed for first 2 yr of life (critical time); at 3 yr of age, VA 20/25 in normal eye and
20/30 in aphakic eye; child now wearing 19 D Silsoft CL (from 29 D), with normal IOP; good outcome
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| Case 2: infant girl, 4 wk of age; underwent CE and IOL implantation in right eye (RE); RE slightly shorter than LE; K
readings same; for emmetropia, calculated 39 D lens; intentionally undercorrected by 8 D, so received 28 D lens; immediately
postoperatively, undercorrected by 7.5 D; over next 7 yr, myopic shift from +7.50 D to -2.75 D; eye patched 50%
during waking hours until 4 yr of age, then patching discontinued; since then, VA 20/20 in both eyes with normal IOP;
good outcome
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| Case 3: child underwent CE with IOL implantation (instead of lensectomy with CL); on first postoperative day, IOL
found tilted, with inferior haptic in visual axis and superior haptic not visible; IOL removed and child fitted with CL; 6
mo later, child developed glaucoma with dense amblyopia (essentially blind)
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| Case 4: girl, 14 yr of age; underwent CE at 1 yr of age in Mexico; also has hearing loss; LE aphakic until child 10 yr of
age, then child started wearing glasses (+5.50 in one eye and +8.50 in other); VA 20/60 in both eyes
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| Case 5: brother of patient from case 4; also underwent CE in Mexico but had IOLs implanted in both eyes; also has hearing
loss; left IOL dislocated into vitreous by trauma; VA hand movements in LE; retinal tear, with IOL resting on bare
retinal pigment epithelium; retina reattached with silicone oil and IOL repositioned; when patient seen by speaker, VA
20/80 in LE and 20/40 in RE; IOL in LE dislocated again, but left alone; glasses prescribed to correct refractive error; 1
yr later, no light perception (NLP) in RE and VA 20/60 in LE; vitreous hemorrhage in RE and total retinal detachment
with multiple retinal cysts
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| Conclusions: cataract surgery in children involves unique issues (eg, amblyopia, axial elongation); good visual outcomes
obtained with IOLs and CLs; Infant Aphakia Treatment Study should help to clarify risks and benefits of IOL implantation
in children
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| PEDIATRIC GLAUCOMA —Faruk H. Orge, MD, Assistant Professor of Ophthalmology and Visual Sciences, and Associate
Director of Pediatric Ophthalmology and Adult Strabismus Section, Case Western Reserve University School of Medicine,
Cleveland, OH
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| Types: primary congenital glaucoma—evident at birth or within first few years of life; dysplasia of anterior chamber angle
present, with no associated ocular or systemic abnormalities; juvenile glaucoma—occurs at >3 yr of age; no associated ocular
or systemic abnormalities; secondary glaucoma—associated with other abnormalities, eg, cataracts, aniridia, iritis
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| Epidemiology: rare; inform family that multiple surgeries and multiple examinations under anesthesia (EUA) possibly
needed; 60% diagnosed by 6 mo of age and 80% within first year of life; 65% of patients boys; 70% of cases bilateral
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| Pathophysiology of congenital glaucoma: developmental arrest in late embryonic period; due to cellular or membranous
abnormality of trabecular meshwork (TM); anomaly of diffuse anterior segment; main feature abnormal insertion
of ciliary muscle
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| Clinical features: classic triad—epiphora (tearing); photophobia (light sensitivity); blepharospasm; other findings include
corneal enlargement, corneal edema, Haab striae, myopia, optic nerve cupping, and optic nerve atrophy; corneal
enlargement—in normal newborn, horizontal diameter of cornea 9.5 to 10.5 mm (12.0-12.5 mm in adults); in glaucomatous
infants, horizontal diameter possibly 14.0 mm; corneal edema—seen in 25% of affected infants at birth and 60% by
6 mo of age; Haab striae—acute rupture of Descemet’s membrane; results from excessive corneal stretching; typically
horizontal or concentric to limbus; myopia—due to stretching of eye; buphthalmos (cow’s eye); optic nerve cupping—
reversible; optic nerve atrophy—permanent damage
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| Causes of vision loss: optic nerve damage; corneal clouding; astigmatism; amblyopia; cataract; lens dislocation; retinal
detachment
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| Intraocular pressure: tends to be elevated; in infant, normal IOP 10 to 20 mm Hg; dramatic (38 mm Hg) or subtle (23
mm Hg); symmetry important; measuring IOP—tonometer (Tono-Pen); possible to measure infants while asleep or feeding;
use midazolam (Versed) or chloral hydrate; usually requires EUA for full assessment; most general anesthetics and
sedatives lower IOP (except ketamine); check IOP early during induction
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| Examination under anesthesia: check IOP during mask induction; recheck after airway secured; generally do not
want pupils dilated (need to see angle and protect anterior lens surface); gonioscopy—direct visualization of angle; findings
include deep anterior chamber, high flat anterior iris insertion, absence of angle recess, and scalloped line; slit-lamp
examination of cornea; measure corneal diameter; A-scan ultrasonography (US); RetCam imaging
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| Treatment: medications—limited effect because primary congenital glaucoma is anatomy problem; temporizing measure;
supplemental if surgery not 100% curative; more effective for secondary types of glaucoma; include β-blockers
and carbonic anhydrase inhibitors; brimonidine used with caution in infants (causes cardiac arrest); surgery—primary
interventions include goniotomy and trabeculotomy; both thought equally effective; both directed at abnormal angle
structures; each procedure opens roughly one-third of angle; may take 3 procedures
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| Goniotomy: direct incision of abnormal TM; disadvantage—requires clear cornea to visualize TM; advantage—leaves
conjunctiva undisturbed, facilitating future surgeries; with needle, make slight slit just above TM; enter cornea through
superior and temporal aspect
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| Trabeculotomy: approaches TM indirectly via Schlemm’s canal; advantage—clear cornea not required; disadvantage—
Schlemm’s canal possibly absent or difficult to identify; necessary to identify Schlemm’s canal
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| Trabeculectomy: creation of fistula by filtering bleb of conjunctiva; with mitomycin C and 5-fluorouracil, success rate
higher; associated with complications (eg, bleb leaks, endophthalmitis) in active child
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| Glaucoma drainage devices: tube-shunt implants; useful in difficult pediatric glaucoma; Ahmed glaucoma valve
implant—very effective in lowering IOP; disadvantages include corneal decompensation and cataract formation from
contact with tube, bleb encapsulation with secondary shunt failure, and migration of implant tube or plate
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| Cyclodestruction: destruction of ciliary body to decrease production of aqueous humor externally or internally; partial
destruction done through cryotherapy, external diode laser (using G-probe), or endoscopic cyclophotocoagulation;
cryotherapy—ciliary body frozen; advantage that effective, quick, and easy to perform; disadvantages include irreversible
hypotony; unintentional damage to adjacent structures (eg, corneal decompensation, cataract formation, retinal
detachment, vitreous hemorrhage)
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| Postsurgical prognosis: if present at birth, prognosis for controlling IOP and preserving vision poor; 50% become legally
blind despite treatment; favorable prognosis if onset at 3 to 12 mo of age; 80% to 90% of cases controlled with surgery
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| Long-term follow-up: careful follow-up required, especially in younger children, to monitor for visual risk factors (eg,
corneal scarring and opacification, optic nerve damage, significant myopic astigmatism); amblyopia significant issue;
also strabismus and anisometropia
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| Long-term visual outcomes: for all congenital and secondary pediatric glaucomas, after 10-yr follow-up, vision 20/40
or better in 60% of patients, 20/40 to 20/200 in 16%, and worse than 20/200 in 24%; close follow-up necessary
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| PEDIATRIC OCULAR TRAUMA —Dr. Lambert
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| Childhood ocular injuries: one-third of all serious eye injuries occur in children; 25% result in monocular blindness;
10% result in enucleation; 4 times more common in boys; most commonly, injury due to sharp object; other causes include
sports-related injuries, air guns, motor vehicle accidents, and powder guns; most common in 6- to 18-yr age group;
corneal lacerations due to sharp objects have good prognosis; blunt trauma injuries have poor prognosis; important to remove
corneal sutures as soon as possible (2-3 wk after injury); important to insert lens implant
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| Hyphema: screen for sickle cell disease or trait (different treatment); patients generally not admitted to hospital; limit activity
for 5 days; treatment topical atropine and corticosteroids (glaucoma medications if IOP elevated); washout performed
if patient develops corneal blood staining or has sickle cell trait; concern about rebleeding (avoided if child’s
activity limited and eye kept covered); risk for increased IOP due to angle recession, inflammation, and erythrocytes
clogging TM (in those with sickle cell trait)
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| Gunshot ocular injuries: eye possible entry site of pellet into brain; air gun injuries frequently involve fovea (bad visual
prognosis)
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| Intraocular foreign bodies: US useful in localizing foreign body
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| Motor vehicle accidents: often unrestrained-passenger or airbag injury; canalicular lacerations—repair with monocanalicular
stent (Mini-Monoka) using microscope; commonly occur after dog bite injuries
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Suggested Reading
Brophy M et al: Pediatric eye injury-related hospitalizations in the United States. Pediatrics 117:e1263, 2006; Chen
TC et al: Aphakic glaucoma after congenital cataract surgery. Arch Ophthalmol 122:1819, 2004; Garcia TA et al:
Spectrum of ocular injuries in children with major trauma. J Trauma 59:169, 2005; Greven CM et al: Circumstance and
outcome of ocular paintball injuries. Am J Ophthalmol 141:393, 2006; Ikeda H et al: Long-term outcome of trabeculotomy
for the treatment of developmental glaucoma. Arch Ophthalmol 122:1122, 2004; Khan AO: Buphthalmos in the setting
of persistent hyperplastic primary vitreous cataract. Am J Ophthalmol 136:945, 2003; Kohlhaas M et al: Effect of
central corneal thickness, corneal curvature, and axial length on applanation tonometry. Arch Ophthalmol 124:471, 2006;
Listman DA: Paintball injuries in children: more than meets the eye. Pediatrics 113:e15, 2004; Muir KW et al: Central
corneal thickness: congenital cataracts and aphakia. Am J Ophthalmol 144:502, 2007; Naik MN et al: Management
of canalicular lacerations: epidemiological aspects and experience with Mini-Monoka monocanalicular stent. Am J Ophthalmol
145:375, 2008; Rabiah PK: Frequency and predictors of glaucoma after pediatric cataract surgery. Am J Ophthalmol
137:30, 2004; Sobaci G et al: Ocular trauma score in deadly weapon-related open-globe injuries. Am J
Ophthalmol 141:760, 2006; Souza C et al: Long-term outcomes of Ahmed glaucoma valve implantation in refractory
glaucomas. Am J Ophthalmol 144:893, 2007; Spierer A et al: Changes in astigmatism after congenital cataract surgery
and intraocular lens implantation: a comparative study. Arch Ophthalmol 122:695, 2004; Trivedi RH et al: Keratometry
in pediatric eyes with cataract. Arch Ophthalmol 126:38, 2008; Wilson ME Jr et al: Eye growth after pediatric cataract
surgery. Am J Ophthalmol 138:1039, 2004.
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