pediatric cataract - for ophthalmology post graduates

1. PAEDIATRIC CATARACT
Cataract is defined as a development of any opacity in the lens or its capsule.
CONGENITAL AND DEVELOPMENTAL CATARACTS
 Congenital and developmental cataracts occur due to some disturbance in the normal
growth of the lens.
 When the disturbance occurs before birth, the child is born with CONGENITAL CATARACT.
Therefore, in congenital cataract the opacity is limited to either embroyonic or foetal
nucleus.
 DEVELOPMENTAL CATARACT may occur from infancy to adolescence. Therefore , such
opacities may involve infantile or adult nucleus, deeper part of cortex or capsule.
 Developmental cataract typically affects the particular zone which is being formed when this
process is disturbed. The fibres laid down previously and subsequently are often normally
formed and remain clear.
 Congenital and developmental opacities assume most variegated appearance and minute
opacities are very common without visual disturbance.
 These are detected with the beam of slit lamp under full mydriasis.
ETIOLOGY
 About 1/3rd
cases are idiopathic
 1/3rd
are hereditary
 Rest 1/3rd
are due to other maternal causes or foetal causes
IDIOPATHIC
 About 33% cases are sporadic and of unknown etiology.
HEREDITORY
 Inherited cases without systemic disorders
o In these cases , the mode of inheritance is usually AD
 Inherited cases with systemic disorders
o Chromosomal disorders (Trisomy 21)
o Skeletal disorders (e.g. Sticklers syndrome)
o CNS disorders (e.g. cerebro-ocula-facial syndrome)
o Renal system disorder (e.g. Lowe’s syndrome)

2. COMMON FAMILIAL CATARACTS
 Cataracta Pulverulenta
 zonular Cataract
 Coronary Cataract and Total soft cataract
MATERNAL FACTORS
 Malnutrition during pregnancy has been associated with nonfamilial zonular cataract
 Infections
o Rubella are associated with 50% of cases.
o Toxoplasmosis
o CMV
 Drug Ingestion
o Thalidomide
o Corticosteroid
 Radiation
o Exposure to radiation during pregnancy may cause congenital cataract.
FOETAL OR INFANTILE FACTORS
 Deficient Oxygenation (anoxia) owing to placental haemorrhage
 Birth Trauma
 Metabolic disorders of the fetus or infant
o Galactosemia
o Galactokinase deficiency
o Neonatal hypoglycaemia
 Cataract associated with other congenital anomalies
o Down’s syndrome
o Lowe’s syndrome
o Myotonia dystrophica
o Congenital icthyosis
 Ocular diseases associated with developmental cataract
o PHPV
o Aniridia anterior chamber cleavage syndrome
o ROP
o Lenticonus posterior
o Microphthalmos
 Malnutrition
o in early infancy may also cause developmental cataract.

3. CLINICAL TYPES
Congenital Capsular Cataracts
 Anterior capsular cataract
 Posterior capsular cataract
Polar Cataract
 Anterior polar cataract
 Posterior polar cataract
Congenital Nuclear Cataracts
 Cataracta Pulverulenta
 Lamellar cataract
 Sutural and axial cataracts
o Floriform cataract
o Coraliform cataract
o Spear shaped cataract
o Anterior axial embryonic cataract
o Dendritic suture cataract
 Total nuclear cataract
Generalized Cataract
 Coronary cataract
 Blue dot cataract
 Total congenital cataract
 Congenital membranous cataract
CONGENITAL CAPSULAR CATARACT
 Anterior capsular cataract
o Non axial
o Stationary
o Visually insignificant
 Posterior capsular cataracts
o Rare
o Can be associated with persistant hysloid artery remnants.

4. POLAR CATARACTS
 Anterior polar cataracts
o It involves the central part of the anterior capsule and adjoining superficial most
cortex.
o It may arise in the following ways
 Due to delayed development of AC .
 Opacity is congenital
 Usually bilateral
 Stationary
 Visually insignificant
 Due to corneal perforation
 Usually after perforation due to ophthalmia neonatorum.
o Morphological types :
 Anterior polar cataract may occur as any of the following morphological
patterns:
 Thickened while plaque in the centre of anterior capsule
 Anterior pyramidal cataract
o In this , the thickened capsular opacity is cone-shaped with
its apex towards cornea
 Reduplicated cataract ( double cataract)
o Sometimes along with the thickening of central point of
anterior capsule, lens fibres lying immediately beneth it also
becomes opaque and are subsequently separated from the
capsule by laying of transparent fibres inbetween.
o The buried opacity is called imprint and the two together
constitute reduplicate cataract.
 Posterior polar cataract
o Very common lens anomaly
o Consists of a small circular circumscribed opacity involving the posterior pole.
o Associations :
 Persistant hyaloid artery remnants (Mittendorf dot)
 Posterior Lenticonus
 PHPV
o Types :
 Stationary Form
 Progressive form which progresses after birth. It typically has an ‘onion
whorl appearance’

5. CONGENITAL NUCLEAR CATARACTS
 Cataracta Centralis Pulverulenta
o Is an embroyonic nuclear cataract
o Dominant genetic trait
o Occurs due to inhibition of the lens development at very early stage, thus involves
the embryonic nucleus.
o This condition is bilateral
o Characterized by a small rounded opacity lying exactly in the centre of the lens.
o The opacity has powdery appearance (pulverulenta)
o Ususally doesn’t afftect vision.
 Lamellar Cataract / Zonular Cataract
o Refers to the developmental cataract in which the opacity occupies a discrete zone
in the lens.
o Most common type of congenital cataract presenting with visual impairment.
o ETIOLOGY
 Genetic or Environmental in origin
 Genetic pattern is usually familial AD variety
 Environmental form is associated with:
 Vitamin D deficiency
 Hypocalcemia
 Maternal rubella infection contracted between 7 to 8th
week of
gestation.
o CHARACTERISTIC FEATURES
 Typically this cataract occurs in a zone of foetal nucleus surrounding the
embryonic nucleus
 Usually bilateral
 Frequently causes severe visual defects
 The main mass of the lens internal and external to the zone of cataract is
clear, expect for linear opacities like spokes of a wheel which may be seen
towards the equater.
 Sutural and Axial Cataract
o SUTURAL CATARACT
 Consists of punctate opacities scattered arounf the anterior and posterior Y-
sutures.
 Usually static and donot have much effect on vision.
 The individual opacities vary in size and shape and have different pattern
and thus are named accordingly :
 Floriform cataract
o Here the opacities are arranged like the petals of a flower
 Coralliform cataract
o Also called as fusiform spindle-shaped axial cataract

6. o Characterized by an anterior – posterior spindle shaped
opacity giving appearance of a coral.
 Spear shaped cataract
o The lenticular opacities are in the form of scattered heaps of
shinning crystalline neddles.
 Anterior axial embryonic cataract
o Occurs as fine dot near the anterior Y-suture of foetal
nucleus
 Dendritic sutural cataract
o Fine dots along the dendritic sutures.
Total Nuclear Cataract
 It usually involves the embryonic and foetal nucleus and sometimes the infantile nucleus.
 It is characterized by a dense chalky white central opacity
 Causes serious impairment of vision
 Opacities are usually bilateral and non-progressive
GENERALIZED CATARACTS
 Coronary Cataract
o Extreamly common form of developmental cataract occurring about puberty.
o Thus, involving either the adolescent nucleus or deeper layer of the cortex.
o The opacities are many hundreds in number and have a regular radial distribution in
the periphery of the lens encircling the central axis.
o Vision is usually unaffected because the opacities are situated at the periphery.
o Sometimes the marginal punctate opacities may marginally reduce the vision.
 Blue Dot Cataract
o Also called as cataracta-punctata-caerulea
o Most common type of congenital cataract.
o Usually forms in the 1st
two decades of life
o The punctate opacities are in the form of rounded bluish dots situated in the
peripheral part of adolescent nucleus and deeper layers of the cortex.
o Opacities are usually stationary and doesnot affect vision.
o Large punctate opacities associated with coronary cataract may marginally reduce
the vision.
 Total Congenital Cataract
o It may unilateral or bilateral
o It can either be hereditary or due to maternal rubella infection.
o RUBELLA CATARACT
 Maternal Rubella infection acquired during 1st
trimester may cause rubella
cataract.

7.  Child is born with a ‘pearly white’ nuclear cataract.
 Progressive type of cataract
o RUBELLA SYNDROME
 Congenital rubella cataract may occur alone or as a part of a classical rubella
syndrome
 OCULAR DEFECTS
o Congenital cataract
o Salt and pepper chorioretinopathy
o Microphthalmos
o Cloudy cornea
o Poorly dilating pupil
 EAR DEFECTS
o Deafness due to destruction of organ of corti
 HEART DEFECTS
o PDA
o Pulmonary Stenosis
o VSD
 Congenital Membranous Cataract
o Sometimes, there may occur total or partial absorption of congenital cataract,
leaving behind thin membranous cataract.
o Rarely , there is complete disappearance of all the lens fibres and only a fine
transparent lens capsule remains behind.
o Such patients may be misdiagnosed as having congenital aphakia.
o This is associated with HALLERMANN-STREIFF-FRANCOIS SYNDROME
DIFFERENTIAL DIAGNOSIS
 Congenital cataract presenting with leucocoria need to be differentiated from :
o Retinoblastoma
o ROP
o PHPV etc.

8. MANAGEMENT OF CONGENITAL AND DEVELOPMENTAL CATARACT
CLINICO-INVESTIGATIVE WORK UP
 A detailed clinic-investigative work up is most important in the management of paediatric
cataract.
 It should aim at knowing the prognostic factors and indications and timing of surgery.
CLINICAL HISTORY :
 Detailed family history
 Detailed history of the child’s growth, development and systemic disorders
GENERAL EXAMINATION :
 Detailed paediatric physical examination
OUCLAR EXAMINATION :
 Corneal Diameter
 Iris configuration
 AC depth
 IOP
 Lenticular Examination
o Density and morphology of cataract
 Density is indicated by QUALITY OF RED REFLEX SEEN ON DISTANT DIRECT
OPHTHALMOSCOPE before and after dilatation of pupil.
 Cataract morphology may suggest underlying cause.
 Posterior segment examination to rule out
o Posterior mass
o RD
o Stalk between optic nerve and lens
 If posterior segment is not visible, B Scan ultrasonography should be performed to asses
anatomical abnormalities of the posterior segment.
VISUAL FUNCTION :
 The mere presence of cataract doesnot suggest that surgical removal is necessary.
 That determination requires assessment of the visual significance of the lens opacity.

9.  In healthy infants AGED 2 months OR YOUNGER
o The fixation reflex may not be fully developed. Thus, its abs in this group of patients
is not necessarily abnormal.
o In general, anterior capsule opacities are not visually significant unless they occlude
the entire pupil.
o Central or posterior lens opacities of sufficient density that are greater than 3mm in
diameter are usually visually significant.
o Opacities that have a large area of surrounding normal red reflex or that have clear
area within them may allow good visual development.
o Strabismus associated with unilateral cataract and nystagmus associated with
bilateral cataract indicate that the opacities are visually significant.
o These signs also indicate that the optimal time for treatment has passed, but
cataract surgery may still improve visual function.
IN PREVERBAL CHILDREN OLDER THAN 2 MONTHS
o Standard clinical assessment of:
 fixation behaviour
 Fixation preference
 Objection to occlusion provide additional evidence of the visual significance
of the cataract.
o For bilateral cataracts:
 Assessment of the child’s visual behaviour and the family’s pbservations of
the child at home help to determine the level of visual function.
o Preferential looking tests and VEP can provide qualitative information
o In older children, particularly those with lamellar and PSC glare testing may be useful
for assessing decreased vision.
LABORATORY INVESTIGATIONS
 Unilateral cataracts are usually not associated with systemic disease; lab tests are therefore
not warranted in these cases.
 Bilateral cataracts are associated with many metabolic or other systemic diseases which
requires lab investigations
 if the child has a positive family history of isolated congenital or childhood cataract or if
examination of parents show lenticular opacities and there are no associated systemic
diseases to explain their cataract, systemic evaluation and lab tests are not necessary.
LAB EVALUATION FOR BILATERAL CATARACTS OF UNKNOWN ETIOLOGY:
 Intrauterine infections : TORCH Test

10. o Toxoplasmosis
o Rubella
o CMV
o Herpes Virus
 Galactosemia
o By urine test for reducing substances, RBC transferase and galactokinase levels.
 Lowe’s syndrome
o Urine chromatography for amino acids
 Hyperglycemia
o Blood sugar levels
 Hypocalcemia
o Serum calcium and phosphate levels
o X-ray Skull.
PROGNOSTIC FACTORS
 Prognostic factors which need to be noted are :
o Density of cataract
o Unilateral or bilateral cataract
o Time of presentation
o Associated ocular defects
o Associated systemic defects
CATARACT SURGERY IN PAEDIATRIC PATIENTS
 TIMING OF THE PROCEDURE
o In general, the younger the child, the greater the urgency to remove the cataract.
 This is because of the risk of deprivation amblyopia.
o For optimal visual developmet,
 A visually significant unilateral cataract should be removed BEFORE AGE 6
WEEKS.
 Visually significant bilateral cataract should be removed BEFORE AGE 10
WEEKS.
o For older children with bilateral cataracts, surgery is indicated when the level of
visual function interferes with the child’s visual needs.
 Surgery should be considered when the visual acuity decreases to 20/40 or
worse.
o For older children with unilateral cataract, cataract surgery is indicated when visual
acuity cannot be improved beyond 20/40

11. INTRAOCULAR LENS USE IN CHILDREN
 The choice of optical device for correction of aphakia depends primarily on the age of the
patient and the laterality of the cataract.
 IOL implantation in children aged 1-2 years and older is widely accepted.
 The use of IOLs in younger infants, are associated with a higher rate of complications and
larger shifts in refractive error with age.
 Early surgical intervention followed by consistent contact lens wear and patching of
uninvolved eye ususally allows development some useful vision.
 In most infants who are left aphakic, secondary IOL implantation can be performed after 1-2
years of age.
 Infants with mild PFV have a higher incidence of adverse events after lensectomy compared
with children with other forms of unilateral cataract, but visual outcomes are similar in both
groups.
MANGEMENT OF THE ANTERIOR CAPSULE
 To enable access to the lens nucleus and cortex during cataract surgery, a capsulorrhexis is
performed.
 Due to the tearing characteristics of the paediatric capsule are quite different from those of
the adult capsule, lens removal techniques are modified for paediatric patients so that risk
of inadvertent extension of the tear is minimised.
 The elasticity of the capsule is greatest in younger patients, especially infants, making CCC
more difficult.
 The pulling force should be directed nearly perpendicular to the direction of the intended
tear and the capsule should be regrapsed frequently to maintain optimal control over the
direction of tear.
 An alternative to capsulorrhexis is vitrectorhexis,
o The creation of an anterior capsule opening using a vitrectomy instrument.
 In children with dense cataracts that obscure the red reflex, visibility of the anterior capsule
can be enhanced with application of trypan blue ophthalmic solution 0.06% to the capsule.
LENSECTOMY WITHOUT IOL IMPLANTATION
 In children who will be left aphakic, lensectomy is done through a small peripheral corneal,
limbal, or pars plana incision with the vitrector.
 Irrigation can be provided by an integrated sleeve or by a separate AC cannula.

12.  Ultrasonic phacoemulsification is not required, as the lens cortex and nucleus are generally
soft in children of all ages.
 Removing all cortical material is important because of the propensity for reproliferation in
paediatric lens epithelial cells.
 Tough fibrotic plaques may require manual excision with intraocular scissors and forceps.
 Because posterior capsule opacification occurs rapidly in young children
o A controlled posterior capsulotomy and anterior vitrectomy should be perfomed.
o This technique allows rapid, permanent establishment of a clear visual axis for
retinoscopy and prompt fitting and monitoring of the aphakic optical correction.
 If possible, sufficient peripheral lens capsule should be left to facilitate secondary PCIOL
later.
LENSECTOMY WITH IOL IMPLANTATION
 Single – piece foldable acrylic IOLs, which can be placed through 3mm clear corneal or scleral
tunnel incision, have become popular in paediatric cataract surgery.
 Larger single-piece PMMA lenses are also still used.
 If an IOL is to be placed are the time of cataract extraction, 2 basic techniques can be used
for lensectomy, depending on whtr the posterior capsule will be left intact.
 Many paediatric cataract surgeons leave the posterior capsule intact if the child is
approaching the age when an Nd:YAG laser is capsulotony in an awake patient could be
performed (usually 5 years of age ).
 Primary capsulectomy is usually preferred for younger children, within 18-24 months of
surgery.
TECHNIQUE WITH POSTERIOR CAPSULE INTACT
 After the cortex is aspirated, the clear corneal or scleral tunnel incision is enlarged to allow
placement of IOL.
 Placement in the capsular bag is desirable, but ciliary sulcus fixation is acceptable
 Closure of 3 mm clear corneal incisions with absorbable suture is safe and does not induce
astigmstism in children.
TECHNIQUES FOR PRIMARY POSTERIOR CAPSULECTOMY
POSTERIOR CAPSULECTOMY/VITRECTOMY BEFORE IOL PLACEMENT
 After lensectomy, the vitrector settings should be set to the low-suction, high cutting rate
appropriate for vitreous surgery.
 A posterior capsulectomy with anterior vitrectomy is then performed.

13.  The anterior capsule is enlarged, if necessary, to an appropriate size for the IOL, and then
the lens is implanted in the capsular bag or the ciliary sulcus.
 The surgeon must take care to ensure that
o Capsulotomy does not extend
o The IOL haptics do not go through the posterior opening
o Vitreous does not become entangled with the IOL or enter the AC.
POSTERIOR CAPSULECTOMY/VITRECTOMY AFTER IOL PLACEMENT
 Some surgeons prefer to place the IOL in the capsular bag, close the anterior incision and
approach the posterior capsule through the pars plana.
 Irrigation can be maintained through the same AC infusion cannula used during lensectomy.
 A small conjunctival opening is made over the pars plana. And a sclerotomy is made with a
microvitreoretinal blade 2.3-3.0 mm posterior to the limbus.
 This provides good access to the posterior capsule and a wide anterior vitrectomy can be
performed.
PROBLEMS FACED WITH IOL IMPLANTATION
 Because the eye continues to elongate throughout the 1st
decade of life and beyond,
selecting an appropriate IOL power is complicated.
 Power calculation in infants and young children may be unpredictable for variety of reason:
o Widely variable growth of the eye
o Difficulty obtaining accurate keratometry and axial length measurement
o Use of power formulas that were developed for adults rather than children.
 Studies have shown that in aphakic paediatric eyes, a variable myopic shift in refractive
arroe of approximately 7.00-8.00 D occurs from 1 to 10 years of age.
o This suggests that if a child is made emmetropic with an IOL at 1 year of age,
refractive error at 10 years of age can be -8.00 D or greater.
 Refractive change in children younger than 1 year of age is even more unpredictable.
 Lens implantation in children requires consideration of the :
o Age of the child
o Target refractive error at the time of surgery
o Refractive error of the contralateral eye.
 Some surgeons implant IOLs with powers that are expected to be required in adulthood.
 Thus, the child initially requires hyperopic correction.
 Other surgeons aim for emmetropia at the time of lens implantation, especially in unilateral
cases.
o Believing that this approach improves the treatment of amblyopia and facilitates
binocular function by decreasing anisometropia in the early childhood.
o These children usually become progressively more myopic and may eventually
require a second procedure to address the increasing anisometropis.

14. POSTOPERATIVE CARE
MEDICAL THERAPY
 If all the cortical material is adequately removed, postop inflammation is usually mild in a
child without IOL implant.
 Topical steroids, antibiotics and cycloplegics are commonly applied for few weeks after
surgery.
 Topical steroids should be used more aggressively in children who have undergone IOL
implantation.
 Some surgeons administer intracameral steroids at the time of surgery and others use oral
steroids postoperatively, especially in very young children and children with heavily
pigmented iris.
 Some surgeons administer intracameral antibiotics in addition to topical antibiotics.
AMBLYOPIA MANAGEMENT
 Amblyopia therapy should begin as soon as possible after surgery.
 For aphakic patients, contact lens or glasses should be used within few weeks of surgery.
 For infants with bilateral aphakia, glasses are the safest and simplest method of correction.
o They can be easily changed according to the refractive shifts that occur with the
growth of the eye.
 Until the child can use a bifocal lens properly, the power selected should make the eye
myopic
o This is because, most infant’s visual activity occurs at near.
 CL can also be used in bilateral aphakic patients.
 For infants with unilateral aphakia, CL are the most common method of correction.
 Advantages of CL
o Relatively easy power changes
o Extended wear CL availability.
 Disadvantages of CL
o Easy displacement by eye rubbing
o Expensive
o Risk of microbial keratitis
 Aphakic glasses are occasionally used in infants with unilateral aphakia who are unable to
tolerate CL.

15.  After optical correction of aphakia, patching of the better eye is necessary in patients with
unilateral cataract and in some patients with bilateral cataract if the visual acuity is
asymmetric.
 Amount of patching is based on the degree of amblyopia and age of the child.
COMPLICATIONS FOLLOWING PAEDIATRIC CATARACT SURGERY
 Strabismus
o Very common in children following surgery either unilateral or bilateral cataracts
 Glaucoma
o The risk of glaucoma is increased in children who have cataract surgery in infancy
and those with small eyes.
 Corneal Decompensation
o Very rare in children
 Retinal Detachment
o Rare
o Most likely to occur when other ocular abnormalities are present.
 Macular Edema
 Postop Endophthalmitis
o Rarely occurs in children.
VISUAL OUTCOME AFTER CATARACT EXTRACTION
 Depends of many factors
o Age of onset
o Type of cataract
o Time of surgery
o Choice of optical correction
o Treatment of amblyopia
 Optimal vision requires careful, long term postop management, particularly amblyopia.