3. INTRODUCTION
⢠Prevalence -1 to 15 cases in 10,000 children in the developing
countries.
⢠10% of childhood blindness
⢠Congenital or Acquired
⢠Visually significant or not
⢠Stable or Progressive
⢠Unilateral or Bilateral
⢠Partial or Complete
4. ANATOMY
Lens - A transparent, biconvex, crystalline
structure between iris & vitreous in a saucer
shaped depression called patellar fossa.
Components
ď§ Anterior capsule
ď§ Anterior capsular epithelium
ď§ Cortex
ď§ Nucleus
ď§ Posterior capsule
5. CONGENITAL VERSUS DEVELOPMENTAL
⢠Congenital & developmental cataracts- not synonymous
⢠In widest sense, most forms of cataract (even senile cataract)
may be considered as developmental, for human lens grows
until late in life
⢠Criteria for congenital cataract
⢠present at birth
⢠situated within fetal nucleus
⢠diameter of opacity less than 5.75mm (diameter of newborn
lens)
⢠If size of opacity more than 5.75mm,cataract must be
postnatal
11. PUNCTATE(BLUE DOT)CATARACT
⢠Most common type,universal
⢠Cataracta coerulea/blue dot cataract
⢠Multiple tiny blue spots scattered all over
lens esp in cortex
⢠Variant âcataracta centralispulverulenta
⢠dominantly inherited,non progressive
⢠central spheroidal/biconvex opacity
consisting of powdery fine white dots within
embronic /fetal nucleus
⢠Non progressive&visually insignificant
12. ZONULAR (LAMELLAR)CATARACT
⢠Accounts for 50% of visually significant cataract
⢠May be congenital or occurs at a later stage as development
interfered at a later stage
⢠They are bilateral and asymmetric. The opacities are in the cortical
layers around the nucleus, just outside the Y sutures.
13. ⢠Linear opacities like spokes of a wheel (called
riders) may run outwards
⢠Usually bilateral,formed just before/shortly after birth
⢠Fill pupillary aperaturewhen pupil undilated, thus
affecting vision
⢠Often hereditary (autosomal dominant)
⢠Associated with hypovitaminosis D (with evidence of
ricket) or hypocalcemia (with tetany or defective tooth
enamel)&maternal
ZONULAR (LAMELLAR)CATARACT
14. CORONARY CATARACT
⢠Around puberty
⢠Situated in deeper layers of cortex
&superficial layers of adolescent
nucleus
⢠Corona or club shaped opacities
near periphery of lens ,usually
hidden by iris while axial region
&extreme periphery remain clear
⢠Non progressive & does not interfere
with vision.
15. NUCLEAR CATARACT
⢠Associated with rubella
⢠Incidence more if infection
contracted in 2nd month
⢠Development of lens inhibited
⢠at very early stage
⢠Embyonal - nuclear cataract
⢠Progressive ,becomes total cataract
⢠Associated microphthalmos,
nystagmus, strabismus, glaucoma,
iris hypoplasia & pigmentary
retinopathy
17. ⢠It comprises of central opacity 3.5mm in diameter
surrounded by clear cortex but may have irregular
opacification adjacent to the nucleus and this tends to
worsen over time.
⢠They commonly have an associated posterior capsule
plaque.
18. ANTERIOR CAPSULAR CATARACT
⢠May be due to
⢠Delayed formation of anterior chamber (Developmental)
⢠Acquired (commonly)-follows contact of capsule with cornea,
⢠usually after perforation of ulcer in ophthalmia neonatorum
⢠Three types-
⢠Anterior polar (flat type)
⢠Anterior pyramidal
⢠Reduplicated
19. ⢠Flat type â white plaque forms in central pupillary area less
than 3mm in diameter
⢠Visually insignificant
⢠Pyramidal type â sometimes central plaque projects forwards
into anterior chamber like a pyramid
⢠Frequently surrounded by area of cortical opacity
⢠may affect vision
⢠It is associated with aniridia, and should prompt a thorough family history
and evaluation for Wilms tumor- aniridia - genital anomalies retardation
(WAGR) syndrome.
ANTERIOR CAPSULAR CATARACT
20. ⢠Subcapsular epithelium may grow in between capsule & cortical opacity
⢠Clear lens fibre subsequently growingfrom there lay down a
transparent zone between two opacities
⢠Buried opacity is calledimprint & two together constitute
Reduplicated cataract
⢠Associationâ
⢠Persistant pupillary membrane
⢠Aniridia
⢠Peters anomaly
⢠Anterior lenticonus
ANTERIOR CAPSULAR CATARACT
21. POSTERIOR CAPSULAR (POLAR)CATARACT
⢠Associated with persistent hyaloid
remnants(mittendorf dots),posterior
lenticonus & persistent anterior fetal
vasculature
⢠Common in minimal degree & visually
insignificant
⢠With persistent hyloid artery , lens deeply
invaded by fibrous tissue leading to total
cataract
22. SUTURALCATARACT
â˘Opacity follows anterior /posterior
â˘Y suture
â˘May occur in isolation or association with other opacity
MEMBRANOUS CATARACT
â˘Rare
â˘Associated with Hallermann-Streiff- Francois syndrome
â˘occurs when lenticular material partially /completely
reabsorbs leaving behind residual chalky â white lens
matter sandwiched between anterior & posterior capsule
23. ANTERIOR LENTICONUS
⢠Anterior lenticonus is a conical or spherical bulging of the anterior
capsule and the underlying cortex seen as an oil droplet appearance
on retinoscopy.
⢠This condition is often bilateral. The discovery of anterior lenticonus
should prompt systemic workup, especially audiologic testing.
⢠Common syndromic associations are Alport syndrome, Waardenburg
syndrome and Fectner syndrome.
24. OIL DROPLET CATARACT
⢠It presents as a faint central opacity in the posterior aspect of
central lens cortex.
⢠It is usually found in galactosemia and restriction of galactose is
normally associated with clearing of cataract in the early stages
25. PEDIATRIC CATARACT AND INTRAUTERINE
INFECTIONS
⢠Maternally transmitted intrauterine infections may result in congenital
cataracts.
⢠Common in India with around 25% of infants
⢠Having congenital rubella associated cataracts.
⢠The most common causative infections are known by the acronym
TORCHS for toxoplasmosis, rubella, cytomegalovirus, herpes simplex
and syphilis.
⢠History of maternal fever/ rash during pregnancy or systemic clinical
indicators in the child such as microcephaly, hearing loss,
developmental delay, thrombocytopenia, hepatosplenomegaly or skin
abnormalities.
26. SYMPTOMS OF DEVELOPMENTALCATARACT
Informant â usually parents
ď§History of white spot in pupillary area
ď§Child is usually brought with history of diminution of vision /
does not recognize objects and parents
ď§Deviation of eye
ď§Associated symptoms of systemic disease, if present
27. SIGNS
⢠Diminished vision (at times it is difficult to
establish in very young children)
⢠Lenticular opacity
⢠Nystagmus
⢠Deviation of eye
⢠There may be other ocular and systemic
abnormalities in cases of rubella nuclear cataract
32. History
⢠Parents of child come with following complaint:
⢠Failure of response to visual targets
⢠White pupillary reflex
⢠Lack of fixation
⢠Deviated eye
⢠Nystagmus
33. History
⢠Age of onset
⢠Maternal history( infection, rash, drug use)
⢠Child growth and developmental milestones
⢠Feeding behavior
⢠Trauma
⢠Review red reflexes in old photographs
⢠Family history
36. ⢠Slit lamp biomicroscopy (under dilatation)
⢠Morphology: size, density, location
⢠Associated anomalies of cornea, iris and Anterior chamber,pupil
⢠Intraocular pressure
⢠Distant Direct Ophthalmoscopy
⢠USG B-scan (posterior segment evaluation)
⢠A scan biometry and keratometery
⢠Examination of both parents and all siblings must be done.
37. On ophthalmoscopy cataract density graded as:
⢠Very dense cataract- occludes pupil completely
⢠Less dense,visually significant - central or posterior
opacities >3mm , retinal vessels visible with indirect
ophthalmoscopy.
⢠Visually insignificant â central opacities <3mm
peripheral opacity
retinal vessels visible with direct, indirect ophthalmoscopy
38. Laboratory workup
⢠Tests for bilateral congenital cataract
Recommended even without any definitive family history
⢠Fasting blood sugar
⢠Plasma Ca & P (hypothyroidism)
⢠Urine reducing substances after milk feeding (galactosemia)
⢠Urine amino acids (Loweâs syndrome)
⢠RBC transferase & galactokinase levels (galactosemia)
⢠TORCH titres
39. Cataract type Associated medical problem Work up required
Nuclear (sporadic) Rubella
Varicella
TORCH
IgG & IgM antibodies
Lamellar (sporadic) Neonatal tetany Ca, phosphorus, PTH
Oil droplet Galactosemia
Galactokinase deficiency
G-1-P uridyl trans def
Urine reducing subs+, urine
glucose-ve, RBC galactokinase
Total (sporadic) Rubella
CMV
TORCH, IgG & IgM ,
Urine culture for CMV
PSC Diabetes
Corticosteroids
Radiation
JRA
Refsum disease
Mannosidase deficiency
Blood glucose, Hb A1 C
History of use
History of exposure
ANA, RF, HLA B27
Phytanic acid
Anterior subcapsular Conradi syndrome X-ray of long bones (stippled
epiphysis)
40. Treatment
⢠Indications for surgery
⢠Visually significant cataract:
occupying visual axis & ⼠3
mm of pupil
⢠U/L partial or complete
cataract
⢠Poor retinoscopic reflex
⢠Cataract with strabismus
⢠Cataract with nystagmus or
unsteady fixation
41. Timing of Surgery
⢠Complete U/L: Immediate
⢠Complete B/L at birth: within first 4-6 weeks of life. Second eye operated within
few days of first.
⢠Complete B/L detected later: Surgery as soon as possible. First on the worse
eye.
⢠Partial U/L or B/L: Surgery only if evidence of visual impairment. Close follow up
required.
The critical period for surgical treatment of dense congenital unilateral cataract.
Invest Ophthalmol Vis Sci 1996; 37:1532-8.
Intervention before 6 weeks of age may minimize the effects of congenital unilateral deprivation on the
developing visual system and provide for optimal rehabilitation of visual acuity
42. Surgical Management
⢠Anesthesia
⢠General Anesthesia is required
⢠Succinyl choline as well as collapsible sclera tend to cause
positive vitreous pressure during surgery
45. Surgical Management
Steps of surgery
⢠Lid speculum applied
⢠Superior rectus suture/Fleiringa ring
⢠Wound Construction
⢠More elastic sclera in children
⢠Large incisions tend to collapse eye during surgery
⢠Small wound required (as no formed nucleus)
⢠Phacoaspiration
⢠I/A
⢠¹IOL implantation
⢠Closure of wound with a suture
46. Surgical incision
Corneal ⢠Increases risk of
endopthalmitis
⢠Higher astigmatism
Scleral
⢠Difficult to perform due
to low scleral rigidity
Superior location â safe
Temporal avoided â life long span post op, trauma risk
Suture all incisions preferably
47. Anterior Capsulorhexis
Prerequisites
⢠Adequate pupillary dilatation
⢠Improve visualisation
⢠Use high magnification and dim OT lights
⢠Avoid positive vitreous pressure
⢠Pre-op I/V Mannitol may be required
⢠Viscoelastic
⢠Highly cohesive viscoelastic
⢠Use liberally
48. Anterior Capsulorhexis
â˘VERY ELASTIC CAPSULE
⢠Deforms without tearing
⢠When it finally tears, the force of the
rebound propagates the tear rapidly &
uncontrollably to the periphery
49. Anterior Capsulorhexis
⢠LOW SCLERAL RIGIDITY
⢠Positive vitreous pressure ďŽ
shallowing of AC ďŽ anterior
surface of lens becomes convex
ďŽ rhexis runs to periphery
50. Anterior Capsulorhexis
⢠DIFFICULT TO USE CYSTITOME
⢠Difficult to advance the everted capsular flap over soft cortex
⢠Less control over rhexis ďŽ tends to extend
⢠RHEXIS FORCEPS
⢠Better control over rhexis
⢠Utrata ďŽ chances of AC shallowing as it is passed through main incision
⢠Special end-gripping type of rhexis forceps
⢠Introduced through side-port ďŽ AC well maintained
51. TECHNIQUE
⢠INITIAL CENTRAL PERFORATION
⢠Forceps
⢠Bent 26-gauge needle
⢠REST OF RHEXIS
⢠Forceps only
⢠Centripetal force instead of usual tangential (ripping
technique)
⢠Performed slowly with repeated re-grasping of flap just
adjacent to edge of tear to prevent peripheral
extension
⢠Always keep AC well-formed with visco-elastic
⢠Aim for small rhexis size as it enlarges due to elasticity
52. ďŹRHEXIS BY RIPPING
ďĄFlap pulled perpendicular to
rhexis edge (i.e. towards
centre)
ďŹOnly this method can tear the
elastic capsule of children
Anterior Capsulorhexis
53. other optionsâŚ
⢠Vitrectorrhexis
⢠Cutting rate 150-300
⢠Aspiration rate 150-
250cc/min
â˘Radiofrequency
diathermy capsulotomy
⢠High frequency current of
500kHz
⢠Platinum alloy tip probe
heated to 160 F
54. cortex & nucleus removal
⢠Multi quadrant cortical-cleaving hydrodissection
⢠To separate epithelial cells from capsule
⢠Reduces surgical time
⢠Reduces amount of irrigation fluid used
⢠Facilitates removal of cortex
⢠Complete removal of cortex important for
⢠Reducing post operative inflammation
⢠Reducing incidence of PCO
55. Surgical Management
â˘Aspiration of lens material
â˘Irrigation- aspiration hand piece alone
â˘Phaco handpiece (for harder nuclei)
â˘Vitreous cutting instrument
56. Surgical Management
â˘Options for surgery:
⢠Lens aspiration without IOL implantation
⢠Lens aspiration with IOL implantation
⢠Technique with posterior capsule intact
⢠Technique with posterior capsulorhexis
⢠Technique with posterior capsulorhexis + anterior
vitrectomy
⢠Rhexis/ Vitrectomy can be done before or after IOL
placement
57. ⢠Anterior vitreous face (AVF) acts as scaffold for epithelial cells to grow
⢠AVF supports metaplastic pigment epithelial & inflammatory cell growth due to
breakdown of blood-aqueous barrier
⢠Inflammatory response in small children can be severe and fibrinous membranes
may form on the intact AVF
⢠Rates of PCO decreases only after AV not PCCC alone in children less than 6years
58. Primary Posterior Capsulorhexis
⢠Indicated in children less than 6 years
⢠Planned posterior capsulotomy performed
⢠To prevent inevitable PCO formation
⢠To remove PC plaque
⢠To allow posterior capture of IOL optic
⢠To prevent radial extension when small PC rupture occurs
inadvertently
⢠To provide more tear resistant edge for anterior
vitrectomy and IOL implantation
59. Posterior Capsulotomy
â˘SECONDARY CAPSULOTOMY
⢠PARS PLANA CAPSULOTOMY + VITRECTOMY
⢠ADVANTAGE
⢠More controlled procedure
⢠DISADVANTAGE
⢠Two stage procedure
⢠Chance of amblyopia in interval
60. STEPS OF PRIMARY POSTERIOR CAPSULORHEXIS
⢠PREREQUISITES
⢠EXCELLENT VISIBILITY
⢠Good microscope
⢠Clear cornea
⢠Sufficient mydriasis
⢠NO POSITIVE PRESSURE
61. STEPS OF PRIMARY POSTERIOR CAPSULORHEXIS
â˘VISCOELASTIC INJECTED IN
CAPSULAR BAG AFTER
CORTICAL CLEAN-UP
⢠Flattens PC by countering
vitreous pressure
62. STEPS OF PRIMARY POSTERIOR CAPSULORHEXIS
⢠CENTRAL PERFORATION WITH
CYSTITOME IN FRONT OF
RETROLENTAL SPACE OF
BERGER
63. STEPS OF PRIMARY POSTERIOR CAPSULORHEXIS
â˘CENTRAL
PERFORATION
⢠26-gauge cystitome
descends at a slant
⢠PC engaged and
punctured
⢠Small flap created by
pushing margin
inferiorly
64. STEPS OF PRIMARY POSTERIOR
CAPSULORHEXIS
â˘SMALL AMOUNT OF
VISCOELASTIC INJECTED
INTO CAPSULAR HOLE
⢠Separates PC from vitreous
⢠Should be done slowly to
avoid extension of tear to
periphery
65. STEPS OF PRIMARY POSTERIOR
CAPSULORHEXIS
⢠RHEXIS COMMENCED WITH
EITHER UTRATA FORCEPS OR
END-GRIPPING FORCEPS
⢠Proceed slowly with repeated re-
grasping of the leading edge in
manner similar to anterior rhexis
66. STEPS OF PRIMARY POSTERIOR
CAPSULORHEXIS
â˘RHEXIS SIZE
⢠Should be 1.5-2 mm smaller
than IOL optic to reconstitute
barrier between vitreous and
anterior chamber
⢠Too small or too big will prevent
IOL optic capture
67. Posterior capsulorhexis + Anterior vitrectomy
⢠PRIMARY POSTERIOR CAPSULORHEXIS
⢠RHEXIS ONLY
⢠DISADVANTAGE
⢠Very high rate of opacification of anterior vitreous face in smaller
children
⢠RHEXIS + ANTERIOR VITRECTOMY
⢠ADVANTAGE
⢠No PCO ďŽ clear optical axis ďŽ less chances of amblyopia
⢠DISADVANTAGE
⢠Disturbance of vitreous face ďŽ ?? CME
68. Anterior Vitrectomy
⢠ANTERIOR VITRECTOMY
⢠Aim is to remove only central anterior vitreous;
not complete peripheral vitrectomy
⢠Two limbal site-ports
⢠For irrigation & for aspiration-cutting
⢠Prevents hydration of vitreous
69. Current recommendations:
â˘Primary PCCC with AV for children < 6-7 yrs of
age
â˘Primary PCCC without AV for > 7 yrs of age
â˘PC left intact in children above 9-10 yrs of age
70. IOL FIXATION SITES
(in order of preference)
⢠Haptics in bag & optic capture by PCCC
⢠Haptics & optic in bag (if PCCC too large or
small for IOL capture)
⢠Haptics in sulcus & optic capture by PCCC (if
incomplete anterior rhexis but complete
PCCC)
⢠Haptics in sulcus & optic capture by anterior
rhexis(if complete anterior rhexis but
incomplete PCCC)
⢠Haptics in sulcus & optic in front of anterior
capsule (if incomplete anterior rhexis &
PCCC)
71. Wound Closure
⢠Scleral closure of 5.5-6 mm incision involves
⢠Continuous shoelace suture or
⢠Combination of continuous and horizontal suture
⢠Small incision (for foldable IOL) may still require suture
72. Complications Of Cataract Surgery
⢠Intraoperative
⢠Hyphema
⢠Iris damage
⢠AC tends to collapse
73. ⢠ANTERIOR UVEITIS
⢠CORNEAL OEDEMA
⢠ENDOPHTHALMITIS
⢠Wound leaks
⢠Iris in wound
EARLY
ONSET
⢠CAPSULAR BAG OPACIFICATION
⢠SECONDARY MEMBRANE FORMATION
⢠PUPILLARY CAPTURE
⢠IOL DECENTRATION
⢠POST OPERATIVE GLAUCOMA
⢠CYSTOID MACULAR OEDEMA
LATE
ONSET
74. Early
ANTERIOR UVEITIS
⢠19%2,3
⢠INCREASED TISSUE
REACTIVITY
⢠FIBRINOUS
MEMBRANE
⢠PIGMENT DEPOSIT ON
IOL
⢠POSTERIOR SYNECHIAE
⢠FREQUENT TOPICAL &
SYSTEMIC STEROIDS
CORNEAL OEDEMA
⢠TRANSIENT CORNEAL
OEDEMA
⢠NO SIGNIFICANT
ENDOTHELIAL CELL
LOSS
ENDOPHTHALMITIS
⢠RARE
⢠STAPHYLOCOCCUS
AUREUS
⢠S. EPIDERMIDIS
⢠S. VIRIDANS
⢠48-96 HOURS
2Gupta AK, Grover AK, Gurha N. Traumatic cataract surgery with intraocular lens implantation in children. J Pediatr Ophthalmol Strabismus
1992;29:73-78
3Eckstein M, Vijayalakshmi P, Killedar M, et al. Use of intraocular lens in children with traumatic cataract in south India. Br J Ophthalmol,
1998;82:911-915
75. Late
POSTERIOR BAG OPACIFICATION
⢠39% - 100% cases where capsule is left intact. Lens aspiration,1960s
⢠Lensectomy with vitrectomy,1970s
⢠IOL implantation,1990s
INFLAMMATORY SECONDARY MEMBRANES
⢠Common complication of paediatric cataract surgery
⢠Nd-YAG laser capsulotomy, early
⢠Surgical membranectomy, more dense
⢠¹ IOL
⢠topical corticosteroids & cycloplegics, posterior capsulecomy,
anterior vitrectomy
76. PUPILLARY CAPTURE
⢠More common in children
⢠Anterior capsulotomy smaller
⢠Visual acuity, IOL malposition, glaucoma
IOL DECENTRATION
⢠Traumatic zonular loss
⢠Inadequate capsular support
⢠40%4
⢠Placement in the bag, explantation/repositioning
4Hiles DA. Intraocular lens implantation in children with monocular cataracts. 1974-1983. Ophthalmology
1984;91:1231-1237
77. POST OPERATIVE GLAUCOMA
⢠3% - 32%5,6,7,8
⢠Risk factors
⢠Microcornea
⢠Cataract surgery before the age of one
⢠Poorly dilating pupils
⢠Congenital rubella
⢠Treatment â primary surgical (goniotomy,trabeculotomy),
medical for refractory
5Egbert JE, Kushner BJ. Excessive loss of hyperopia: presenting sign of juvenile aphakic glaucoma. Arch Ophthalmol 1990;108:1257-
1259.
6Simon JW, Metge P, Simmons ST, et al. Glaucoma after pediatric lensectomy/vitrectomy. Ophthalmology 1991;98:670-674.
7Walton DS. Pediatric aphakic glaucoma: a study of 65 patients. Trans Am Ophthalmol Soc 1995;93:403-420.
8Vajapyee RB, Angra SK, Titiyal JS, et al. Pseudophakic pupillary block glaucoma in children. Am J Ophthalmol 1991;11:715-718.
78. Follow-up Care
Medication
⢠Topical
⢠Steroid-antibiotics
⢠Cycloplegics
⢠Anti-glaucoma
⢠Systemic steroids
⢠For intense fibrinous reaction
⢠For 1 month
⢠Keep water out of eye
⢠Refrain from play & rough sports
⢠Wear eye shields during sleep
79. Follow-up Care
Refraction
⢠Should be performed in the first two weeks of
surgery
⢠Glasses / Contact Lenses prescribed
⢠Aphakic correction
⢠Ametropia > 1D hyperopia
> 4D myopia
⢠Repeated refraction important to keep pace with
changing refraction of growing eye so as to avoid
amblyopia
⢠Close followup mandatory till 10 years of age
80. Suture Removal
⢠Become loose sooner than adults
⢠Irritation, discomfort, infiltration
⢠Astigmatism of 3 and 1.5 D at 1 and 2 months after surgery
is the indication for suture removal.
.
81. Visual Prognosis
⢠Poor Prognosis:
⢠Congenital U/L amblyogenic cataract is delayed beyond 4-6
months of age
⢠Presence of nystagmus or strabismus
⢠Axial cataract
⢠Traumatised eye with corneal scarring
⢠Complications related to surgery(CME, glaucoma, synechiae,
infection)
83. OPTICAL REHABILITATION OF APHAKIA
SPECTACLES
⢠Most commonly used in bilateral infantile aphakia.
⢠Advantages:
⢠They are affordable
⢠Can be frequently changed
⢠Disadvantages
⢠Cosmetically not pleasing
⢠Provides suboptimal image quality
Hence, contact lens rehabilitation is also recommended in this
category.
Secondary IOL implantation should be considered once eyes
are mature
84. ⢠Aphakic glasses:
- Frame selection- smallest, earpieces, spring hinges
- Economical, safe
- Not suitable for unilateral cases
- Restricted field, magnified image
85. OPTICAL REHABILITATION OF APHAKIA
CONTACT LENS
⢠Preferred option in uniocular aphakic infants
⢠Should be fitted as soon as possible after cataract
extraction
Secondary IOL implantation should be considered
once eye is mature or child becomes resistant to
contact lens.
86. ⢠Contact lenses:
- Relatively safe and effective provided appropriate lens fit,
good lens care, compliance with proper hygiene
- Better field of vision and image size differences
- Suitable for unilateral aphakia
- Lens loss, difficulty in insertion and corneal complications
are major drawbacks
87. IOL Implantation
IOL IMPLANTATION BEFORE 1 YEAR OF AGE CONTROVERSIAL
⢠Difference in size of globe compared to adult eye & rapid growth (axial length,
corneal curvature, lens diameter & sulcus size) ďŽ unpredictable refractive
status
⢠Technical difficulty of implanting IOL in very small eyes
⢠Greater inflammatory response
Hence, IOL implantation is controversial prior to 12 months of age.
Most surgeons implant after 18-24 months of age
⢠Most of the growth of eye has occurred by this time
⢠IOL power calculation is more predictable.
88. IOL Power Calculation
⢠AL increases at a rate of 0.18 mm/wk until 40 weeks
⢠Average axial length at birth: 16.8 mm
⢠The AL of infants at 3 months :18.23 mm (0.15 mm/week until the age of 3 months)
⢠By 16 years: 23.6 mm
⢠Most of this growth (6 mm) equivalent to 20 D of myopia, occurs within first two
years of age.
⢠Corneal power drops from average power of 51.2 D to 43.5 D , offsetting around 10
D of myopia.
Hence, implanting fixed emmetropic IOL in children < 2 years will render the child
highly myopic with risk of development of amblyopia.
89. IOL Power Calculation
⢠IOL power must provide:
⢠Satisfactory post operative refractive correction to overcome
amblyopia
⢠Should not result in myopic shift
⢠Partly achieved by undercorrecting eye in anticipation of
myopic shift
⢠Leaves child hypermetropic post operatively
⢠Hypermetropia, even of small degree, may be amblyogenic, and
should be corrected
90. IOL Power Calculation
⢠Dahanâs criteria
⢠Age<2 yrs: undercorrect by
20%
⢠Or use axial length only
⢠Age 2-8yrs
⢠Undercorrect by 10%
⢠Hiles and Atkinson
⢠<2yrs:20-50% undercorrect
⢠>2 yrs: emmetropic
91. IOL Size
⢠Lens diameter
⢠At birth: 7 mm
⢠At 2 years: 9 mm
⢠Adult size: 9.6 ¹ 0.39 mm
⢠Adult size IOL (12-13.5 mm) well tolerated in children > 2 years due to
elastic nature of the capsule
⢠In children less than 2 years, smaller size (10-10.5 mm) IOL must be
used.
⢠Optic size: 5.5-6.5 mm ensures adequate pupillary coverage in case of
decentration
92. IOL design and material
⢠Flexible, open, modified C loop, 1 piece all PMMA IOL
⢠Heparin coated PMMA IOL (HSM)
⢠Significantly reduce deposits on IOL surface
⢠Single piece acrylic IOL
⢠Foldable AcrySof IOL (preferred now a days)*
⢠The Single-piece AcrySof IOL provided satisfactory visual
axis clarity, produced an acceptable inflammatory
response, and maintained centration in pediatric eyes.
*Single-piece AcrySof intraocular lens implantation in children with congenital and
developmental cataract
JCRS,Volume 32, Issue 9, Pages 1527-1534 (September 2006)
93. Amblyopia Therapy
Occlusion therapy
⢠Mainstay of amblyopia therapy in:
⢠Operated monocular cataracts
⢠Disparity of vision in those who have undergone
bilateral surgery
⢠Continue occlusion therapy till child is 6-7 years
of age
94. Prevention Of Amblyopia
Patching regimen
Age in months Occlusion
⢠0-1 month No patching
⢠1-2 months 1 hour/day
⢠2-4 months 2-3 hours/day
⢠4-12 months 6 hours/day
⢠> 12 months 12 hours/day
Visual Acuity Occlusion
⢠6/36 or worse 6 hours/day (partial occlusion)
⢠6/24 or better 12 hours/day (full time occlusion)
6:1 Occlusion done to prevent occlusion amblyopia
95. Follow-up Care
Repeated follow up visits to detect:
⢠Posterior capsular opacification
⢠All children will have PCO requiring YAG capsulotomy /
membranectomy
⢠Even those with primary posterior capsulotomy with anterior
vitrectomy may develop PCO
⢠Repeat capsulotomies are common in children
⢠Glaucoma
⢠Strabismus
96. FOLLOW-UP CARE & PREVENTION OF AMBLYOPIA
IMPORTANT!
⢠REFRACTION
⢠Prescribe frequently to maintain clear focussed images on the
fovea
⢠FAILURE TO TREAT CO-EXISTING AMBLYOPIA WILL
NEGATE THE BEST SURGICAL RESULT