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Clinical Education / Pediatric Ophthalmology Education Center / Browse Topics

NOV 11, 2015

Pěđįǻțřįč Čǻțǻřǻčțș: Ǿvěřvįěẅ

By M. Edward Wilson, MD

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İňțřǿđųčțįǿň ǻňđ ěpįđěmįǿŀǿģỳIn children, cataract causes more visual disability than any other form of treatable blindness.

Children with untreated, visually significant cataracts face a lifetime of blindness at tremendous

quality of life and socioeconomic costs to the child, the family, and the society. More than 200,000

children are blind from unoperated cataract, from complications of cataract surgery, or from ocular

anomalies associated with cataracts. Many more children suffer from partial cataracts that may

slowly progress over time, increasing the visual difficulties as the child grows. The cumulative risk

of cataract during the growing years is as high as 1 per 1000.

The management of cataracts in childhood is tedious and often difficult, requiring many visits over

many years. Success requires a dedicated team effort that often involves parents, primary care

pediatricians, surgeons, anesthesiologists, technicians, orthoptists, low vision rehabilitation

specialists, and community health workers.

Čŀǻșșįfįčǻțįǿň (Čǻțěģǿřįżǻțįǿň)Cataracts in children can be classified using a number of methods including age of onset, etiology,

and morphology.

Ǻģě ǿf ǿňșěț

Čǿňģěňįțǻŀ/İňfǻňțįŀě

While the presence of lens opacities at birth indicates a congenital onset, the diagnosis andrecognition of a lens opacity at a later age does not exclude a congenital onset. It is critical to

provide a detailed description of the type of lens opacities before the cataract is extracted and in the

operative note so the type can be determined and any later study correlating genetic etiology or

associated systemic disease can be done more accurately. Some morphological categories of

cataracts such as anterior polar, central fetal nuclear, and posterior polar clearly indicate a

congenital onset, while others such as cortical or lamellar may be associated either with a later

onset or be congenital in nature.

Ǻčqųįřěđ/JųvěňįŀěThis category can be confusing. Strictly speaking, an acquired cataract is one from an external

cause, as opposed to one in which the cause is genetically determined, such as a mutation in one

of the crystalline genes. However, some would use acquired to indicate an onset after infancy,

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which does not necessarily indicate a non-genetic cause. Juvenile cataracts are by definition those

with an onset in childhood, after infancy, irrespective of underlying etiology.

Ěțįǿŀǿģỳ

Ģěňěțįč

Approximately 50% of childhood cataracts are caused by mutations in genes that code for proteins

involved in lens structure or clarity. Table 1 lists genes in which mutations can cause cataracts.While many of these genes are dominantly inherited, others are autosomal recessive or X-linked.

Drawing a pedigree and recognizing some cataract and ocular phenotypes that are associated with

specific mutations will help determine the probable mode of inheritance and the possible underlying

syndrome. Recent advances in genetic testing, including next generation sequencing, allow the

determination of the precise genetic cause of isolated congenital cataracts in 75% of individual

families and 63% of those with syndromic congenital cataracts. Mutations in crystallins account for

50% of isolated (no associated systemic abnormalities) cataracts, while mutations in the gap

junction protein connexins account for 25% of cases and mutations in genes for heat shock

transcription factor-4, aquaporin-0, and beaded filament structural protein-2 account for theremaining 25%.

Metabolic disorders can cause cataracts, which may have particular morphologies that point to the

underlying cause. Next generation sequencing of genes associated with syndromic or metabolic

cataracts can provide a precise diagnosis if the systemic findings do not allow recognition of the

metabolic or systemic illness. Table 1 summarizes findings in some of the main diseases

associated with acquired syndromic cataracts.

Trauma remains a major cause of acquired cataracts in children. Traumatic cataracts are more

common in boys and can be the result of penetrating or blunt injuries to the eye. One has to be

careful in ruling in or out the presence of an intraocular or intraorbital foreign body, hence the

importance of a detailed physical examination and of imaging studies such as ultrasonography and

computed tomography. Magnetic resonance imaging (MRI) studies are contraindicated if the foreign

body is suspected to be metallic.

Table 1. Common causes of congenital or early acquired cataracts

Disease Location Gene Phenotype OMIM number

AUTOSOMAL DOMINANT

Hyperferritinemia-cataract syndrome 19q13.33 FTL Congenital nuclear cataract and

elevated serum ferritin

600886

Coppock-like cataracts2q33.3 CRYGC Dusty opacity of the fetal nucleus

with frequent involvement of the

zonular lens

60430722q11.23 CRYBB2

Volkmann type congenital cataract 1p36 Unknown Central and zonular cataract 115665

Zonular with sutural opacities 17q11.2 CRYBA1 Zonular cataracts with sutural

opacities

600881

Posterior polar 1 (CTPP1) 1p36.13 EPHA2 Opacity located at back of lens 116600

Posterior polar 2 (CTPP2) 11q23.1 CRYAB Single well-defined plaque in

posterior pole of lens; bilateral 613763

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Posterior polar 3 (CTPP3) 20q11.22 CHMP4B Progressive, disc-shaped, posterior

subcapsular opacity 605387

Posterior pole 4 (CTPP4) 10q24.32 PITX3 Single well-defined plaque in

posterior pole of lens 610623

Posterior pole 5 (CTPP5) 14q22-q23 U nknown

Mat reflex of posterior capsule that

progresses into well-demarcated

disc in posterior pole, forming

opaque plaque

610634

Zonular pulverulent 1 (CZP1) 1q21.2 GJA8

Lenticular opacities located in the

fetal nucleus with scattered, fine,

diffuse cortical opacities and

incomplete cortical 'riders'

116200

Zonular pulverulent 3 (CZP3) 13q12.11 GJA3

Central pulverulent opacity

surrounded by snowflake-like

opacities in anterior and posterior

cortical regions of the lens

601885

Anterior polar cataract 1 14q24-qter Unknown Small opacities on anterior surfaceof lens

115650

Anterior polar cataract 2 17q13 Unknown Small opacities on anterior surface

of lens 601202

Cerulean type 1 (CCA1) 17q24 Unknown Peripheral blue and white opacities

in concentric circles 115660

Cerulean type 2 (CCA2) 22q11.23 CRYBB2

Numerous peripheral blue flakes

and occasional spoke-like central

opacities

601547

Cerulean type 3 (CCA3) 2q33.3 CRYGD Progressive blue dot opacities 608983

Crystalline aculeiform cataract 2q33.3 CRYGD

Needle-like crystals projecting in

different directions, through or close

to the axial region of the lens

115700

Nonnuclear polymorphic congenital

cataract 2q33.3 CRYGD

Opacities between the fetal nucleus

and the cortex of the lens 601286

Sutural cataract with punctate and

cerulean opacities 22q11.23 CRYBB2

Dense, white opacification around

the anterior and posterior Y sutures,

oval punctate and ceruleanopacities of various sizes arranged

in lamellar form

607133

Myotonic dystrophy 1 (DM1) 19q13.32 DMPK

Myotonia, muscular dystrophy,

cataracts, hypogonadism, frontal

balding, and ECG changes

160900

Polymorphic and lamellar cataracts 12q13.3 MIP Lamellar, sutural, polar and cortical

opacities604219

Cataract, autosomal dominant, multiple

types 1 3q22.1 BFSP2 Nuclear and sutural opacities. 611597

AUTOSOMAL RECESSIVE


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Congenital cataracts, facial

dysmorphism, and neuropathy

(CCFDN)

18q23 CTDP1

Congenital cataracts, facial

dysmorphism, neuropathy, delayed

psychomotor development, skeletal

anomalies, microcornea and

hypogonadism

604168

Marinesco-Sjögren syndrome 5q31.2 SIL1

Congenital cataracts, cerebellar

ataxia, muscle weakness, delayed

psychomotor development, short

stature, hypergonadotrophic

hypogonadism, and skeletal

deformities

248800

Warburg micro syndrome 12q21.3

RAB3GAP1

Microcephaly, microphthalmia,

microcornea, optic atrophy, cortical

dysplasia, in particular corpus

callosum hypoplasia, severe

mental retardation, spastic diplegia,

and hypogonadism

600118

Warburg micro syndrome 21q41

RAB3GAP2

614225

Warburg micro syndrome 3 10p12.1 RAB18 614222

Martsolf syndrome 1q41 RAB3GAP2 Mental retardation, hypogonadism,

microcephaly

212720

Hallermann-Streiff syndrome (Francois

dyscephalic syndrome) 6q22.31 GJA1

Brachycephaly, hypotrichosis,

microphthalmia, beaked nose, skin

atrophy, dental anomalies, short

stature

234100

Rothmund-Thomson syndrome 8q24.3 RECQL4

Skin atrophy, telangiectasia, hyper-

and hypopigmentation, congenital

skeletal abnormali ties, premature

aging, increased risk of malignant

disease

268400

Smith-Lemli-Opitz syndrome 11q13.4 DHCR7

Microcephaly, mental retardation,

hypotonia, , polydactyly, cleft

palate

270400

Congenital nuclear cataracts 2 22q11.23 CRYBB3 Nuclear cataract with cortical riders 609741

X-LINKED

Norrie disease Xp11.3 NDP Early childhood blindness, mental

disorder, sensorineural deafness 310600

Nance Horan syndrome Xp22.13 NHS

Males have dense nuclear

cataracts, microcornea, dental

abnormalities, and developmental

delay. Carrier females have

posterior Y-sutural cataracts with

small corneas

302350


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Xu LT, Traboulsi EI. Genetics of congenital cataracts. In: Wilson ME, Trivedi RH, editors. Pediatric

Cataract Surgery: Lippincott, Walters Kluwer 2014. p. 1-8.

Șěčǿňđǻřỳ

Uveitis – Cataracts develop in patients with uveitis as a result of the chronic ocular inflammation or

secondary to the chronic use of steroids. Surgery for such cataracts can be complicated by severe

postoperative inflammation, hence the need for absence of preoperative inflammation in the anterior

segment of the eye and the pre-, intra-, and post-operative use of various combinations of topical,

subconjunctival, intracameral, and sometimes systemic steroids. Many patients will have a

pupillary membrane that covers the lens and attaches to the iris, making surgery more difficult.

Such membranes can be peeled off of the anterior lens capsule at the time of surgery to facilitate

lens removal. The use of an intraocular lens (IOL) is left to the discretion of the individual surgeon.

Intraocular tumors – It is very uncommon for cataracts to develop as a consequence of

intraocular tumors. The lens is characteristically clear in patients with untreated retinoblastoma.

Treatments of the tumor such as radiotherapy may lead to the development of cataracts, in which

case timing of cataract removal has to be very carefully considered and surgery only performed

when all tumor in the eye has been eradicated. Patients with radiation cataracts can have

significant ocular surface dryness and will not tolerate contact lenses, hence the need for

intraocular lens (IOL) implantation.Chronic retinal detachment – These cataracts are seen in the setting of injuries or in association

with Stickler syndrome. If the lens is totally opaque, preoperative ultrasonography should be

performed to rule out a chronic retinal detachment. The presence of an afferent pupillary defect is a

poor prognostic sign.

Maternal infection (rubella) – This type of cataract has not been seen in countries where rubella

has been eradicated, but continues to occur in some parts of the world.

İǻțřǿģěňįč

Mǿřpħǿŀǿģỳ

Juvenile idiopathic arthritis: One of the more common causes of anterior uveitis in

children. The use of systemic antimetabolites in recent years has led to better control of

uveitis in such patients and to a reduction in the incidence of cataracts.

Other types of uveitis can also cause cataracts either because of the inflammation or as acomplication of steroid use.

Radiation – External beam radiation is avoided in patients with retinoblastoma. The eye is

typically shielded if radiation is given to the brain or other parts of the head and neck.

Systemic steroids are very rare causes of cataracts in children. Inhaled steroids for asthma

do not cause cataracts. The typical steroid-induced cataract is posterior subcapsular.

Vitrectomy – A large percentage of children who undergo vitrectomy develop cataracts.

These are mostly posterior subcapsular.

Laser for retinopathy of prematurity – Cataracts can develop from thermal injury to the

lens when a prominent tunica vasculosa lentis is present.


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As mentioned above, it is important to utilize the appropriate terminology to describe pediatric

cataracts. The morphology can give a clue to the underlying etiology (isolated or associated with

systemic disease), and possibly to the visual prognosis following surgery.

Đįffųșě/Țǿțǻŀ

This is not an uncommon type of congenital cataract. There are no specific causes of diffuse or

total cataracts.

Ǻňțěřįǿř

Anterior polar – The opacity is in the capsule itself and can protrude into the anterior chamber as

a small mammillation. There may be an underlying circular layer of cortical opacity slightly larger

than the white polar opacity. While the majority are stable and do not interfere with vision, some can

progress and require surgical removal. They can be dominantly inherited, especially in bilateral

cases. Unilateral cases can be associated with anisometropia (astigmatism or hyperopia), which if

left untreated can cause amblyopia, even if the cataract itself is not visually significant.

Figure 1. Anterior polar cataract.

Pyramidal – These are usually larger than polar cataracts and more likely to progress to visual

significance. They are difficult to remove with a vitrectomy instrument and may require excision and

removal with forceps before the rest of the lens is aspirated.


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Figure 2. Pyramidal cataract.

Anterior lenticonus – This refers to a thinned-out central anterior capsule with or without anterior

cortical opacities. Anterior lenticonus is said to be characteristic of Alport syndrome. Spontaneous

rupture of the lens can occur, resulting in a hydrated total cataract.


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Figure 3. Anterior lenticonus (Courtesy of K. David Epley).

Čǿřțįčǻŀ ŀǻměŀŀǻř

In this type of cataract, the opacification is of a lamella (an ovoid layer of cortex) that can bevisualized between adjacent clear lamellae. These are frequently associated with radial “rider”

opacities. Familial lamellar cataracts are mostly autosomal dominant and are generally associated

with a good visual prognosis after their removal. They can be stable or may be associated with

progressive opacification of intervening cortex, necessitating removal.


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Figure 4. Lamellar cataracts (Top: Courtesy of K. David Epley, MD. Bottom: Courtesy of Faruk H.

Örge, MD).

Fěțǻŀ ňųčŀěǻř

These opacities occupy the central-most part of the lens. They can be dot-like or can be quite

dense. They generally measure 2-3.5 mm and can be associated with microphthalmia. They are

said to be associated with a higher incidence of postoperative glaucoma because of associated

microphthalmia and the need for surgery early in infancy.

Figure 5. Congenital nuclear cataract.

Pǿșțěřįǿř pǿŀǻřIn this type of cataract, the opacity is in the capsule itself. It is necessary to differentiate posterior

polar from posterior subcapsular cataracts. Posterior polar cataracts are genetically determined

and some have been associated with mutations in PITX3.


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Figure 6. Posterior polar cataract.

Pǿșțěřįǿř ŀěňțįģŀǿbųș (ŀěňțįčǿňųș)

In this group of conditions, the central and sometimes paracentral posterior capsule is thin and

bulges posteriorly. This usually occurs at the location where the hyaloid system attaches to the

eye. The distortion can cause a localized area of extreme myopic refraction. There may or may not

be subcapsular cortical opacification. Interference with vision can be the result of optical distortion

or of capsular opacification. Most cases are unilateral, although bilateral and familial cases have

been reported. Surgery is associated with good visual outcomes in most cases. Spontaneous

rupture of the lens can rarely occur, leading to abrupt progression to total cataract.

Figure 7. Posterior lentiglobus (lenticonus) cataract. (A) Early clear defect in central posterior

capsule and (B) early opacification of central defect. (C) Ultrasound biomicroscopy of advancedposterior lenticonus.


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Pǿșțěřįǿř șųbčǻpșųŀǻř

These can be congenital but are more commonly acquired as a result of injury or steroid use. The

opacities are cortical and do not involve the capsule proper.

Figure 8. Posterior subcapsular cataract.

Pěřșįșțěňț fěțǻŀ vǻșčųŀǻțųřě (PFV) (șěvěřě vǻřįěțįěș ǻřě șțįŀŀ řěfěřřěđ țǿǻș pěřșįșțěňț ħỳpěřpŀǻșțįč přįmǻřỳ vįțřěǿųș)

The lens opacities in patients with PFV are generally capsular and can be associated with

shrinkage, thickening, and vascularization of the capsule. There may be a posterior plaque outside

or involving the lens capsule with a clear lens that nonetheless must be treated as a cataract.

Figure 9. Persistent fetal vasculature.

Țřǻųmǻțįč đįșřųpțįǿň ǿf ŀěňș

In children, traumatic anterior lens capsule rupture quickly results in a hydrated white cataract.

However, in children, lens cortex in the anterior chamber may be well tolerated without anintraocular pressure (IOP) rise. Cataract surgery can often be delayed for a few days or up to 3 or

4 weeks to allow the traumatic iritis to subside before the cataract and IOL surgery.


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Figure 10. Traumatic disruption of lens (Courtesy of K. David Epley).

Ěvǻŀųǻțįǿň ǻňđ ẅǿřķ-ųpŘǿŀě ǿf vįșįǿň șčřěěňįňģVision screening is mandatory to detect cataracts as soon as possible. Late detection may result in

poor visual outcomes. All newborns must have red reflex screening, ideally followed by another red

reflex examination at the 6-8 week neonatal checkup. Red reflex testing is done by using direct

ophthalmoscope from a distance of 1-2 feet in a darkened room. Preschool vision screening (at 3

and 5 years) is often done in the community. Photo screeners are used in preverbal and verbal

children. These may help the pediatrician save time in screening. They work by a computer analyzing the red reflex for inequality in color, intensity, or clarity. New screeners utilizing polarized

laser light are more accurate at detecting decreased vision. The presence of any opacities, an

absent red reflex, or leukocoria should prompt an urgent referral to a pediatric ophthalmologist.


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Ěvǻŀųǻțįǿň bỳ țħě ǿpħțħǻŀmǿŀǿģįșț A detailed history is taken that includes asking about the child’s developmental milestones, and

about health problems in the siblings and parents. Visual assessment is conducted by using age-

appropriate testing. When the child is two months old, vision assessment can be done with forced

preferential looking techniques (eg, Teller acuity cards, Cardiff cards), fixation and following

evaluation, and assessing objection to occlusion of each eye. The presence or absence of

nystagmus is noted. Subjective visual testing (HOTV matching, LEA symbols, or tumbling Es) isdone as soon as the child is able to play a matching game or identify the symbols and letters.

These tests can usually be done at age 3 years and above.

Biomicroscopy (standard or portable slit lamp examination) is completed. Severity and morphology

of the cataract and any associated abnormalities of cornea or anterior segment are documented.

Examination of siblings and parents might indicate inherited cataracts. Intraocular pressure is

checked if possible.

If there is a view of the retina, full retinal examination documenting optic nerves, retina, and fovea is

performed. If there is no view, ultrasonography (B-scan) is carried out. If there is trauma, then childabuse must be ruled out. In unilateral cataracts, laboratory tests are not needed.

For bilateral cataracts, if there is family history of childhood cataracts, the child has no other

medical problems, and the parents have lens opacities, then systemic and laboratory evaluations

are not needed. If there is no family history of cataracts, a pediatric systemic evaluation is required

because these cataracts may be associated with systemic or metabolic disease. Laboratory tests

may also be needed. The ophthalmologist often works in conjunction with a pediatrician and/or a

clinical geneticist when directing the laboratory work-up. A urine test for reducing sugars, TORCH

(toxoplasmosis, rubella, cytomegalovirus, varicella) screening, a Venereal Disease Research

Laboratory (VDRL) test for syphilis, and a blood test for calcium, phosphorus, glucose, and

galactokinase levels can be checked.

Most inherited cataracts are autosomal dominant. Recessive and X-linked cataracts are less

common. Genetic testing is a rapidly evolving field. Mutations that cause congenital cataracts have

been discovered in over 100 genes. Using the latest sequencing tests, it will be possible to check

all genes involved in congenital cataracts from one blood sample. This might lead to quicker and

cheaper personalized treatment and counseling by the geneticist.

If cataracts are less than 3 mm in diameter or are of partial density, they may be observed or treated with dilating drops. Any dense central opacity in the lens of three or more mm in a young

child is significant and requires surgery. In addition to the size of cataract, blackening of the

retinoscopic reflex is the most important factor determining need for a surgery. In an older child,

any opacity causing a decrease in quality of life should be considered for surgery. At the same

time, the loss of accommodation that occurs when a child’s lens is removed should be taken into

account when making a surgical decision. With increasing age, visual demands of the child

increase and the assessment of whether a partial cataract is visually significant has to be

constantly revisited.

Biometry is done to get keratometry measurements, preferably without a speculum. Axial length isoften measured in children by A-scan ultrasound, with the immersion method being more accurate

than the contact method. Often, these measurements are not possible in clinic and examination

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under anesthesia is required. If the child is older and cooperative, and the cataract is not very

dense, then optical biometry is done.

For calculation of the IOL, third-generation theoretical formulae (eg, SRK/T, Holladay I & II, Hoffer Q

I & II, and Haigis) can be used. Target refraction may be aimed for initial hypermetropia (high or

low) or emmetropia. Suggested target refractions for age are given in Table 2. Other factors such

as amblyopia, fellow eye condition or refraction, assumed compliance, and parental refractive error

should also be taken into consideration when interpreting the table: one IOL power choice for everyage does not work for every situation.

Table 2. Age at cataract surgery and residual refraction

recommendations for target refraction

Age at cataract surgery Residual refraction (Diopters)

8 +1 to 0

Șųřģěřỳ

Ẅħǿ șħǿųŀđ pěřfǿřm țħě șųřģěřỳ Adult cataract surgery is a major emphasis of residency training programs in ophthalmology. The

skills needed to perform adult cataract surgery are also important for performing pediatric cataract

surgery, but additional skills are needed for the pediatric surgery. Pediatric cataract surgery should

only be performed by ophthalmic surgeons who perform them on a weekly or biweekly basis so

that they can perform them with a high level of competency. For this reason, most large group

practices assign only one surgeon in their practice to perform these surgeries. When possible,children should be referred to regional centers where large numbers of pediatric cataract surgeries

are performed. After the postoperative period, in most cases these children can then be followed on

a long-term basis by a local doctor and only referred back to the regional center if problems arise.

Pediatric ophthalmologists interested in performing pediatric cataract surgery should pursue

fellowship training at an institution where they will be trained how to perform pediatric cataract

surgery. After completing their fellowship, they should take instructional courses as needed to

incorporate new techniques as they arise. While adult cataract surgeons are usually skillful at

performing intraocular surgery, they often have not been taught the special techniques required to

successfully perform pediatric cataract surgery. If they are interested in performing pediatriccataract surgery, they should seek out opportunities to learn its best practices either by

observation or by taking instructional courses.

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Țįmįňģ ǻňđ čřįțįčǻŀ pěřįǿđIn the 1960s, Hubel and Wiesel introduced the concept of a “latent period” and a “critical period”

for visual development. During the latent period, visual deprivation has no lasting effect on vision in

the deprived eye. After the latent period, there is a critical period during which visual deprivation

results in irreversible vision loss in the deprived eye. The critical period for a child with a cataract

extends to age 9-10 years.

ŲňįŀǻțěřǻŀThe optimal age for performing cataract surgery in a child with a unilateral congenital cataract is

generally agreed to be 6 weeks of age. Birch and Stager evaluated the relationship between the

age at cataract surgery and visual outcomes in newborns with a dense unilateral congenital

cataract. The model that best fit their data was bilinear, with no differences in the visual outcomes if

the surgery was performed between birth and age 6 weeks. However, after age 6 weeks, there

was a linear decline in visual outcomes related to the age at cataract surgery. Their model would

suggest that there is a 6-week latent period for dense unilateral cataracts in humans. More recently,

Hartmann et al found that the age at cataract surgery was only weakly associated with visual

acuity. While the median visual acuity was better among patients who had cataract surgery

between ages 4 and 6 weeks, the association between age at cataract surgery and the visual

outcome was less robust than the data reported by Birch and Stager.

Bįŀǻțěřǻŀ

It is generally agreed that bilateral congenital cataracts should be removed by 8 weeks of age to

achieve the best visual outcomes. Lambert and coworkers noted that delaying cataract surgery

to 10 weeks of age or later increased the likelihood of a 20/100 or worse visual outcome. Birch and

coworkers reported a bilinear relationship between the age of surgery and the visual outcome in

infants with dense bilateral congenital cataracts. Between birth and 14 weeks of age they noted

progressively worse visual outcomes the older a child was at the time of cataract surgery.

However, after age 14 weeks until 31 weeks, the visual outcome was independent of the child’s

age at the time of cataract surgery. Since it is unclear if there is a latent period in children with

dense bilateral congenital cataracts, the timing of cataract surgery in these children is often

determined by other comorbidities and the increased risk of glaucoma associated with very early

cataract surgery.

Țħřěșħǿŀđ/įňđįčǻțįǿň fǿř șųřģěřỳĐěțěřmįňįňģ țħě ňěěđ fǿř șųřģěřỳ įň přěvěřbǻŀ čħįŀđřěň

Dense cataracts that block the red reflex before the pupils are dilated and are associated with

abnormal visual behavior should be removed during infancy. Other signs suggestive of visually

significant cataracts are strabismus in a child with a unilateral cataract or nystagmus in a child with

bilateral cataracts. Incomplete cataracts do not always require cataract surgery. If the child has

incomplete cataracts and normal visual behavior and the fundi can be clearly viewed with an

ophthalmoscope, cataract surgery should be deferred. Generally, posterior lenticular opacities are

more visually significant than anterior lens opacities. If the incomplete cataract(s) is unilateral or

asymmetrical, part-time patching therapy of the normal/better eye may be beneficial to improve or

maintain vision in the most affected eye.

Vįșųǻŀ ǻčųįțỳ čħǻřț țħřěșħǿŀđ fǿř șųřģěřỳ

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Generally, cataract surgery should not be performed on children with bilateral cataracts who have

best corrected visual acuity of 20/40 or better. However, the visual threshold for performing

cataract surgery should be tailored to the needs of the child. For instance, if a child has visual

acuity worse than 20/40, but is doing well in school and does not have any visual behavioral

problems, cataract surgery can be deferred until later. Visual behavior is less helpful in assessing

the need for cataract surgery in children with a unilateral cataract. Generally, if best corrected

visual acuity cannot be improved to 20/50 or better with amblyopia therapy, cataract surgery should

be considered.

Vįșųǻŀ đỳșfųňčțįǿň ẅěįģħěđ ǻģǻįňșț pǿșț-ǿp ŀǿșș ǿf ǻččǿmmǿđǻțįǿň

The improvement in visual acuity associated with cataract surgery must be weighed against the

loss of accommodation associated with removing the crystalline lens. While multifocal or

accommodative IOLs are available for adults and may mitigate, somewhat, the loss of

accommodation associated with cataract surgery, they are infrequently implanted in growing

children because of the refractive changes that occur as an immature eye grows. Parents should

be told that while their child may see more clearly after undergoing cataract surgery, the child will

have to wear bifocals in order to optimize distance and near vision.

İňfǿřměđ čǿňșěňț/pǻřěňțįňģ čǿųňșěŀįňģThe risks and benefits of cataract surgery should be clearly outlined to parents. It is often helpful to

show them models of the eye or illustrations to help them understand what a cataract is and how

cataract surgery will be performed. The importance of amblyopia therapy and optical correction

following cataract surgery should be discussed in detail. The pros and cons of implanting an IOL or

creating a posterior capsulotomy should be discussed with parents. It should also be explained that

the US Food and Drug Administration (FDA) has not approved the implantation of IOLs in children,and their use in children is off-label.

İmměđįǻțě șěqųěňțįǻŀ bįŀǻțěřǻŀ čǻțǻřǻčț șųřģěřỳ fǿřčħįŀđřěňThe option of performing immediate sequential bilateral cataract surgery should be discussed with

the parents of infants, particularly if there are comorbidities that increase the risk of general

anesthesia. They should be informed of the risks and benefits associated with immediate sequential

bilateral cataract surgery, including the benefit of administering only one general anesthetic, but the

increased risk of bilateral endophthalmitis. It should also be explained that precautions will be

taken to reduce the risk of endophthalmitis, including using different trays of instruments for each

eye, disposable cannulas, re-draping between eyes, and using different lots of irrigating solution

and medications for each eye.

Ǻňěșțħěșįǻ mǻňǻģěměňț čǿňșįđěřǻțįǿňșGeneral anesthesia is required to perform pediatric cataract surgery. The anesthetic agents should

be administered only under the direct supervision of an anesthesiologist with special experience or

special training in pediatric anesthesia. Very young children, especially when born prematurely, willoften need to be hospitalized overnight after cataract surgery because of their increased risk of

experiencing apnea after undergoing general anesthesia. Cataract surgery can be performed as an

outpatient procedure in older children.

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Ǿpěřǻțįvě țěčħňįqųěșPreoperative preparation is typically done using povidone-iodine. The use of intracameral antibiotics

in either the irrigating solution or injected postoperatively has been extensively tested in adults, and

while not widely practiced among pediatric cataract surgeons, trends forecast more acceptance in

the coming years.

Surgical incisions are usually done anteriorly through clear cornea or using a scleral tunnel. If no

IOL is to be placed, a minority of surgeons will opt for a posterior pars plana/plicata approach.Continuous curvilinear capsulorhexis with or without capsular staining is the gold standard

capsulotomy, but vitrectorhexis also works well and is commonly used in the first few years of age

when the capsule is very elastic. The anterior chamber is maintained with either a separate non-

held infusion cannula (an anterior chamber maintainer) or with matched hand-held bimanual

irrigation and aspiration handpieces. Pupil dilation is enhanced with non-preserved epinephrine or

phenylephrine/ketorolac (recently FDA approved for adults) added to the infusion bottle.

The lens contents are aspirated completely (Figure 11). Phacoemulsification ultrasound energy is

never needed with pediatric cataracts. Hydrodissection is not necessary, but can be used at thesurgeon’s discretion. However, the large number of pediatric lens opacities associated with

posterior capsule pathology must be noted. Hydrodissection is contraindicated in posterior polar

cataracts.

Figure 11. An irrigation/aspiration handpiece removing a lamellar cataract (Courtesy of Faruk H

Orge).

A posterior chamber IOL inserted into the capsular bag is always preferred, but ciliary sulcus

placement of a foldable acrylic or single-piece rigid IOL can be done. In cases of no capsular

support, posterior chamber IOLs can be sewn in place; however, placement of iris (claw) fixated

lenses is becoming more popular.

In children too young to tolerate a YAG laser posterior capsulotomy in the office, a primary posterior

capsulotomy at the time of initial cataract surgery is recommended. This can be done either before

or after an IOL is placed and can be done anteriorly through the corneal tunnel or posteriorly

through the pars plana. All but the smallest watertight incisions should be closed in children, usually

with a synthetic absorbable 10-0 suture.


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Pǿșțǿpěřǻțįvě měđįčǻțįǿňș

Ǻňțįbįǿțįčș After pediatric cataract surgery, either moxifloxacin or tobramycin, the two most widely used

antibiotic eye drops, can be used. The eye drops are instilled four times per day for a week. There

is no need to prescribe systemic antibiotics.

ȘțěřǿįđșPrednisolone eye drops are the mainstay of treatment to control severe inflammation, which is

generally inevitable. In some cases of very severe postoperative inflammation, steroid eye drops

must be instilled as frequently as on an hourly basis. Otherwise, the routine dosage range is 4-8

times per day. Some surgeons advocate supplementing the topical steroid with oral prednisolone

dosed at 1 mg/kg/day for the first week to help reduce inflammation.

Čỳčŀǿpŀěģįčș ǻňđ mỳđřįǻțįčșHomatropine or atropine eye drops are sometimes used postoperatively as cycloplegics. Thepossible side effects of atropine must be discussed with the patient’s parents.

Fǿŀŀǿẅ-ųpPediatric cataract cases are normally examined on the first postoperative day. The next follow-up

depends on the amount of inflammation but is most often at 1 week after surgery. Once both eyes

are operated on, periodic examinations are required to determine refraction, IOP, and retinal

evaluation. Glasses or contact lenses are prescribed as early as possible, preferably within the first

week for aphakic correction and within 4 weeks for residual refractive error in pseudophakic

children.

FřěqųěňčỳTypical follow-up frequency is as follows: postoperative day 1, week 1, month 1, month 3, every 3

months for 2 years, and thereafter every 6 months for 3 years.

ĚvǻŀųǻțįǿňIt is crucial to check visual acuity, ocular alignment, IOP, refraction, and clarity of the visual axis at

every visit. Should there be any complication detected in any of the follow-up visits, it should be

tackled promptly.

Ǿpțįčǻŀ řěħǻbįŀįțǻțįǿň ǻfțěř čǻțǻřǻčț șųřģěřỳSince uncorrected refractive error in the early years can lead to amblyopia, attention to appropriate

refractive correction after cataract surgery is crucial in order to obtain good final visual acuity. For infants and toddlers, refractive correction should result in good near vision (myopic refraction of


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approximately -2 diopters). However, correction for distance vision and a bifocal correction for near

viewing should be offered after the age of 2 or 3 years, or by pre-kindergarten. Children who use a

contact lens may also benefit from a spectacle overcorrection after age 2 or 3 years.

ȘpěčțǻčŀěșFor children who have IOL implantation, some residual refractive error is typical and spectacle

correction may be needed for distance and/or near viewing. Additionally, when IOL implantationoccurs at an early age, the growing eye will experience a myopic shift, so that changing refraction

is expected with residual hyperopia in the early years but some degree of myopia expected later.

Correction of aphakia with spectacles may be preferred for infants and young children in whom IOL

implantation is not possible or is purposely delayed. Aphakic spectacles are generally well

tolerated, particularly by children who are bilaterally aphakic. Unilateral aphakia can also be

corrected with spectacles, though this is less desirable because of marked image-size disparity

(aniseikonia) and potential disruption of binocular vision, if present.

Čǿňțǻčț ŀěňșěșContact lens correction of aphakia is often planned for very young infants after lensectomy,

typically with either a silicone elastomer lens (extended wear) or rigid gas permeable lens (daily

wear). One advantage of contact lens wear is easy adjustment in power for the rapidly changing

refractions encountered in young children. Contact lens correction of residual refractive error is

also possible after IOL implantation, and is sometimes requested by adolescent patients.

Pǿșțǿpěřǻțįvě Čǿmpŀįčǻțįǿňș ǻňđ ȘěqųěŀǻěPostoperative complications after pediatric cataract surgery are inversely proportional to the age at

the time of surgery. Associated ocular anomalies, surgical technique, and follow-up duration are

some of the other important variables influencing the prevalence and severity of the postoperative

complications after cataract surgery in children.

Vįșųǻŀ ǻxįș ǿpǻčįfįčǻțįǿňIf the posterior capsule is left intact at the time of cataract surgery in children, posterior capsule

opacification (PCO) is inevitable. The younger the child, the more acute will be the opacity. After

primary posterior capsulectomy and vitrectomy, visual axis opacification (VAO) is rare in older children; however, despite posterior capsulectomy and vitrectomy, VAO is commonly observed in

infants. VAO in infants receiving posterior capsulectomy and vitrectomy typically requires surgical

removal from 3 months to 1 year after the original surgery, while PCO in older children who had an

intact posterior capsule typically requires Nd:YAG laser or surgical removal of the PCO 2 years or

more after cataract surgery.

Ģŀǻųčǿmǻ

Secondary glaucoma is the most sight-threatening complication of pediatric cataract surgery.Younger age at the time of surgery is the most commonly reported risk factor. Open-angle

glaucoma can develop months to many years after the surgery, and children must be followed for

this regularly for their entire life.

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İňfŀǻmmǻțǿřỳ čǿmpŀįčǻțįǿňșDue to increased tissue reactivity, inflammatory complications (eg, anterior chamber cell and flare,

cell deposits on the IOL optic, posterior synechiae, etc.) are more frequently observed in children.

Toxic anterior segment syndrome (TASS) is a rare inflammatory condition usually observed during

the early postoperative period.

Čǿňțǻčț ŀěňș řěŀǻțěđBacterial keratitis, corneal opacity due to tight contact lenses, and corneal vascularization are the

most common contact lens-related complications.

İǾĿ mǻŀpǿșįțįǿňExcessive capsular fibrosis and asymmetric IOL fixation are the most common causes leading to

malposition of an IOL. It can also occur because of traumatic zonular loss and/or inadequate

capsular support. The IOL may have to be repositioned or explanted in some cases when there is

significant decentration/dislocation.

ĚňđǿpħțħǻŀmįțįșThe incidence of postoperative endophthalmitis in children is similar to that reported in adult

surgery. Common organisms are Staphylococcus aureus, Staphylococcus epidermidis, and

Streptococcus viridans. Recent studies in adults have reported a marked decrease in

endophthalmitis when intracameral antibiotics are used. In the US, the absence of an ophthalmic

preparation specific for use as an intracameral injection has slowed adoption of intracameral

antibiotics for fear of toxicity from dilution errors during medication preparation. Studies in adults

have used cefuroxime, vancomycin, and undiluted moxifloxacin.

Řěțįňǻŀ đěțǻčħměňțThe incidence of retinal detachment (RD) following pediatric cataract surgery appears to have

decreased markedly as surgical techniques have advanced. However, because RD may develop

many years after surgery, a retinal examination is recommended after cataract surgery at least

yearly. This is especially important for those eyes at higher risk for RD by virtue of a long axial

length for age, persistent fetal vasculature, traumatic cataract, ectopia lentis, Stickler syndrome,

repeated surgeries, etc.

Mỳǿpįč șħįfț A tendency toward axial elongation and a myopic shift of refraction is well known. This is more

concerning if the child receives an IOL. The younger the child at the time of implantation, the higher

the myopic shift. High myopia in pseudophakic eyes can be treated using spectacles or contact

lens. Alternatively, IOL exchange, piggyback IOL implantation, or corneal refractive surgery may be

required.

Ǿțħěř čǿmpŀįčǻțįǿňș

16, 17, 18, 19, 20


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Corneal edema, corneal decompensation, iris prolapse, heterochromia iridis, suture-related

complications, a postoperative IOP spike, astigmatism, ptosis, or phthisis bulbi are other

complications reported after pediatric cataract surgery.

Șțřǻbįșmųș

Strabismus can coincide with congenital cataract and is more commonly seen in unilateral casesbut not rare in bilateral cataract cases, especially when nystagmus is present. Esotropia is the

most common form of strabismus in congenital cataract, although cyclovertical strabismus may

also contribute to the clinical picture. In a minority of patients, exotropia of the involved eye is the

presenting sign of congenital cataract.

Mǻňǻģěměňț ǿf čǿ-ěxįșțįňģ ǻmbŀỳǿpįǻDeprivation amblyopia is very common in children with unilateral cataract, especially when the

opacity is congenital or infantile. Also, children with bilateral cataracts can develop unilateral or bilateral deprivation amblyopia when the cataracts are asymmetric, when they are removed too

late, or when the aphakia is not properly corrected. Sensory nystagmus will further limit visual

outcome. The management of the amblyopia should start as soon as possible, since compliance in

small infants is better than in 2- to 3-year-old children. Patching of the sound eye is the mainstay of

treatment. However, atropine penalization can be an alternative if the amblyopic eye can take over

fixation. This is quite rare because the aphakic or pseudophakic eye has lost accommodation and

for that reason is always at a disadvantage to the sound eye, which can accommodate up to 10

diopters depending on the child’s age. In bilateral aphakic eyes with contact lenses, the contact

lens of the dominant eye can be removed a few hours or several days per week as a penalizationstrategy. The younger the child, the better the effect of amblyopia treatment per hour of occlusion.

Ŀǿẅ vįșįǿň řěħǻbįŀįțǻțįǿň ǻňđ qųǻŀįțỳ ǿf ŀįfěměǻșųřěșIn cases when the treatment of the congenital cataract is less successful, low vision rehabilitation

has an important role in how the patient can cope with the limited visual capacities in education and

daily life. In most countries, visual rehabilitation and education for visually impaired and blindpatients are organized either by the government, various nongovernmental organizations, or private

foundations. The motto should be: Use the remaining visual function with all other senses to

achieve the optimum quality of life.

Fųțųřě đįřěčțįǿňșEarly detection will allow more timely treatment of pediatric cataract in the future. Vision screening

programs and improved education of primary health care workers and the public will help with this

evolution. Surgical techniques continue to improve and will allow childhood cataract removal withless and less surgical trauma. Planning for IOL implantation will become easier as our knowledge of

myopic shift and axial globe growth evolve. Ultimately, future IOL technological advances will be

aimed at restoration or preservation of youthful accommodation and the ability to easily compensate


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for the inevitable myopic shift. Intracameral medications specifically for ophthalmic use are being

developed and these will improve outcomes for children as they decrease the reliance we now

have on the ability of parents to administer topical medications after surgery.

Řěfěřěňčěș

1. Gilbert C. Worldwide causes of blindness in children. In: Wilson ME, Saunders RA, TrivediRH, eds. Pediatric Ophthalmology: Current Thought and a Practical Guide. Heidelberg,

Germany: Springer; 2009: 47-60.

2. Haargaard B, Wohlfahrt J, Fledelius HC, Rosenberg T, Melbye M. Incidence and cumulative

risk of childhood cataract in a cohort of 2.6 million Danish children. Invest Ophthalmol Vis

Sci . 2004;45(5):1316-1320.

3. Xu LT, Traboulsi EI. Genetics of congenital cataracts. In: Wilson ME, Trivedi RH, editors.

Pediatric Cataract Surgery: Techniques, Complications and Management . Philadelphia:

Lippincott Williams & Wilkins; 2014: 1-8.

4. Gillespie RL, O'Sullivan J, Ashworth J, Bhaskar S, Williams S, Biswas S, et al. Personalizeddiagnosis and management of congenital cataract by next-generation sequencing.

Ophthalmology . 2014;121(11):2124-2137 e1-2.

5. Serafino M, Trivedi RH, Levin AV, Wilson ME, Nucci P, Lambert SR, et al. Use of the Delphi

process in paediatric cataract management. Br J Ophthalmol . 2015. doi:

10.1136/bjophthalmol-2015-307287. [Epub ahead of print].

6. Trivedi RH, Wilson ME. Prediction error after pediatric cataract surgery with intraocular lens

implantation: Contact versus immersion A-scan biometry. J Cataract Refract Surg .

2011;37(3):501-505.

7. Trivedi RH, Wilson ME. Axial length measurements by contact and immersion techniques inpediatric eyes with cataract. Ophthalmology . 2011; 118(3):498-502.

8. Bell CM, Hatch WV, Cernat G, Urbach DR. Surgeon volumes and selected patient outcomes

in cataract surgery: a population-based analysis. Ophthalmology . 2007; 114(3):405-410.

9. Hubel DH, Wiesel TN. The period of susceptibility to the physiological effects of unilateral eye

closure in kittens. J Physiol . 1970; 206(2):419-436.

10. Birch EE, Stager DR. The critical period for surgical treatment of dense congenital unilateral

cataract. Invest Ophthalmol Vis Sci . 1996; 37(8):1532-1538.

11. Hartmann EE, Lynn MJ, Lambert SR, Infant Aphakia Treatment Study Group. Baseline

characteristics of the infant aphakia treatment study population: predicting recognition acuityat 4.5 years of age. Invest Ophthalmol Vis Sci . 2014; 56(1):388-395.

12. Lambert SR, Lynn MJ, Reeves R, Plager DA, Buckley EG, Wilson ME. Is there a latent

period for the surgical treatment of children with dense bilateral congenital cataracts? J

AAPOS. 2006;10(1):30-36.

13. Birch EE, Cheng C, Stager DR Jr, Weakley DR Jr, Stager DR Sr. The critical period for

surgical treatment of dense congenital bilateral cataracts. J AAPOS. 2008; 13:67-71.

14. Dave H, Phoenix V, Becker ER, Lambert SR. Simultaneous vs sequential bilateral cataract

surgery for infants with congenital cataracts: Visual outcomes, adverse events, and

economic costs. Arch Ophthalmol . 2010; 128(8):1050-1054.15. Wilson ME, Jr., Trivedi RH, Buckley EG, Granet DB, Lambert SR, Plager DA, et al. ASCRS

white paper. Hydrophobic acrylic intraocular lenses in children. J Cataract Refract Surg .

2007; 33(11):1966-1973.


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16. Braga-Mele R, Chang DF, Henderson BA, Mamalis N, Talley-Rostov A, Vasavada A.

ASCRS Clinical Cataract Committee. Intracameral antibiotics: Safety, efficacy, and

preparation. J Cataract Refract Surg . 2014; 40(12):2134-2142.

17. Tan CS, Goh AG, Ngo WK, Lim LW, Fam HB. Safety of intracameral antibiotic use after

cataract surgery. J Cataract Refract Surg . 2014; 40(11):1940-1941.

18. Shorstein NH, Winthrop KL, Herrinton LJ. Decreased postoperative endophthalmitis rate after

institution of intracameral antibiotics in a Northern California eye department. J Cataract

Refract Surg . 2013; 39(1):8-14.

19. Espiritu CR, Caparas VL, Bolinao JG. Safety of prophylactic intracameral moxifloxacin 0.5%

ophthalmic solution in cataract surgery patients. J Cataract Refract Surg . 2007; 33(1):63-68.

20. Beselga D, Campos A, Castro M, Fernandes C, Carvalheira F, Campos S, Mendes S,

Neves A, Campos J, Violante L, Sousa JC. Postcataract surgery endophthalmitis after

introduction of the ESCRS protocol: a 5-year study. Eur J Ophthalmol . 2014; 24(4):516-519.

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NOV 10, 2015

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Documents

Pediatric Cataracts_ Overview - American Academy of Ophthalmology