cataract

1. APPROACH TO
PAEDIATRIC CATARACT

2. PREVALENCE
◦ 1.5 million children blind worldwide.
◦ Paediatric cataract accounts for 7.4%-15.3% of paediatric
blindness.
◦ The prevalence of childhood cataract is about 1.03/10,000
children.
◦ Approx. 40,000 children with cataract in india

3. ETIOLOGY AND ASSOCIATIONS OF
PAEDIATRIC CATARACT
◦ Congenital cataract is associated with
- ocular abnormalities in 27% of cases
- systemic abnormalities in 22% of cases
◦ Most unilateral and a significant number of bilateral
cataracts are idiopathic in nature.
◦ Crystallin and connexin gene mutations are the most
commonly described non-syndromic inherited cataracts.

4. ETIOLOGY OF PAEDIATRIC CATARACT
◦ Idiopathic –M/C
◦ Genetic-congenital cataract is hereditary in 8.3-25% of cases,with 75% being AD in inheritance.
◦ Intra-uterine infections-10-15%(rubella,varicella,toxoplasmosis,herpes simplex).
◦ Metabolic-8-10%(galactosemia,hypocalcemia,hypoglycemia,dehydration)
◦ Trauma-20-30%
◦ Prematurity
◦ Syndromic

5. A-zonular cataract with riders ,B-cataract pulverulenta,C-Anterior polar cataract(plaque type),
D-anterior polar cataract(pyramidal type),E-Posterior lenticonus(oildroplet sign),F-posterior polar cataract,G-
sutural cataract,H-morgagnian cataract

6. WORK-UP
History
Ocular examination
Laboratory studies
Paediatric evaluation

7. HISTORY
Parents of child come with following complaints-
1.Failure of response to visual targets
2.White pupillary reflex
3.Lack of fixation
4.Deviated eye
5.Nystagmus

8. HISTORY
Age of onset, duration of symptoms
Maternal history (infection,rash,drug use)
Developmental history, milestones
History of LBW and pre-term delivery
Any history suggestive of any associated systemic
abnormality
Trauma, Previous treatment, or surgery
Family history of congenital cataract and consanguinity

9. VISUAL ASSESSMENT
• PREVERBAL CHILDREN
#Fixation Behavior-fix and follow light,
CSM method
#Preferential looking test
-Teller acuity cards
-Visual evoked potential (VEP)
#Optokinetic nystagmus drum

10. VISUAL ASSESSMENT
VERBAL CHILDREN
Landolt c
Allen picture cards
Snellen’s chart
Tumbling E
LEA symbols
Log MAR

11. Anterior segment
examination
Slit-lamp Exam / Torch light
Morphology-size,density,location and its laterality
Associated anomalies of cornea,iris and anterior
chamber,pupil
Intraocular pressure/squint/nystagmus

12. Examination of
The Red Reflex
◦ k/c/o Bruckner test
◦ For detection of visual axis
opacities,strabismus,refractive errors and
retinal abnormalities.
◦ Done by DDO
◦ To assess density and morphology of
cataract.

13. Posterior segment
examination
Dilated fundus examination-to look for any post
segment anomaly
R/O vitreous haemorrhage,RD,persistent foetal
vasculature or any intraocular mass in the post
segment
Ultrasound B-scan-if fundus is not visible by IO

14. Visually significant cataract
◦ Centrally or posteriorly located
◦ Size >3mm
◦ Visual acuity < 20/60
◦ Decrease in contrast sensitivity
◦ Increased glare
◦ Loss of stereo acuity
◦ Not able to observe the disc and macula with direct ophthalmoscope,especially on dilated pupil
◦ Congenital sensory nystagmus,strabismus

16. Laboratory Investigations
Complete hemogram
Blood sugar
Urine routine microscopy
Serum calcium and phosphate levels for hyper or hypoparathyroidism.
VDRL for syphilis
Antibody titer for TORCH.
Red cell galactokinase or uridyl transferase for galactosemia
Urine protein for Alport syndrome
Urine amino acid for Lowe syndrome
Urine sodium nitroprusside/ plasma homocysteine for homocystinuria
Urine/serum copper for Wilson disease
Karyotyping for a genetic defect
GA work up

17. MANAGEMENT
Surgical or conservative mx ?
If surgery,then what?
Primary IOL implantation ?
If not,how to manage aphakia?

18. NON-SURGICAL
Cataracts not in visual axis
In visual axis but <3mm diameter
Rx-Mydriatrics with part time occlusion of the better eye
But prolonged cycloplegia causes amblyopia-early sx reqd

19. SURGICAL-INDICATIONS
Visually significant cataract-U/L or B/L
U/L dense cataracts
Central and >3mm
Cataract with Strabismus
Cataract with nystagmus or unsteady fixation
One eye operated in a binocular cataract
Poor retinoscopic reflex

20. Small eyes/low scleral
rigidity
Positive pressure/elastic
AC/difficult rhexis
Biometry IOL power
calculation
Increased inflammatory
response/constant
change in refractive error
Glaucoma/amblyopia/gla
sses
Post-op mx of
aphakia/amblyopia
CHALLENGES

21. TIMING OF
SURGERY
Dense visually significant B/L cataract-
6-8 weeks of age (Each eye one week
apart- to prevent amblyopia)
U/L visually significant cataract -4-6
weeks
B/L cataract detected later-surgery as
soon as possible.First on the worse
eye.

22. Techniques of biometry
◦ Hand-held keratometer- lack of fixation and centration
◦ Inaccurate keratometric values-error of 0.8-1.3 D in children
◦ Obtaining multiple readings of the same and recording the
average K reading
◦ K readings without speculum are preferred (causes globe
deformation and gives unreliable readings)

23. Techniques of biometry
◦ Inaccurate AL in paediatric eyes - 4-14 D of error for each
mm difference
◦ For contact A-Scan,the value with maximum AC depth
chosen to offset the inadvertent indentation of the cornea.
◦ Immersion A-Scan is considered gold standard

24. IOL formulae
AL <20mm- SRK/T and the
Holladay 2 formulae
OLDER CHILDREN(>2yrs)
AL<22 MM –Hoffer Q formula
AL>22 MM- Barrett and SRK/T
formulas are better

25. IOL POWER CALCULATION
Aim for moderately hypermetropic postoperative refractive
outcome to compensate for myopic shift which is expected
in children due to axial elongation of the globe.
IOL can be implanted in eyes with an AL >17mm and
corneal diameter >10mm

26. IOL POWER CALCULATION
◦ Dahan’s criteria:
◦ <2 yrs-undercorrect by 20%
◦ 2-8 yrs-undercorrect by 10%
◦ DAHAN’S GUIDELINES
◦ Hiles and Atkinson criteria:
◦ <2 yrs-20-50% undercorrect
◦ >2 yrs-emmetropic
AXIAL LENGTH (MM) IOL POWER(D)
17 28
18 27
19 26
20 24
21 22

27. IOL SIZE
In children <2 yrs,smaller size (10-10.5mm)IOL
must be used
Adult size IOL (12-13.5mm) well tolerated in
children >2 yrs d/t elastic nature of the capsule
Optic size-5.5-6.5mm ensures adequate
pupillary coverage in case of decentration

28. IOL MATERIAL
Acrylic Hydrophobic foldable IOL’s – Increased uveal
biocompatibility,reduced post-op inflammation and
PCO rates
Single piece PMMA,preferably heparin coated-
reduce deposits on IOL surface
Children with juvenile rheumatoid
arthritis,microcornea,microphthalmos,severe
persistent foetal vasculature are left aphakic.

29. IOL implantation ??
• IOL IMPLANTATION BEFORE 1 YR OF AGE CONTROVERSIAL
• Difference in size of globe compared to adult eye & rapid growth(AL,corneal curvature,lens
diameter&sulcus size). Unpredictable refractive status
• Technical difficulty of implanting IOL in very small eyes
• Greater inflammatory response
• Secondary glaucoma
• VAO
• Most surgeons prefer implant after 18-24 months of age
• Most of the growth of eye has occurred by this time
• IOL power calculation is more predictable

31. SURGICAL PRINCIPLES
General Anaesthesia and EUA
Lid speculum applied
Superior rectus suture
Wound construction
Anterior capsulorrhexis
Irrigation and aspiration
Primary posterior capsulorrhexis
Anterior vitrectomy
IOL implantation
Closure of wound with a suture

32. General Anaesthesia and
EUA
Systemic co-morbidities
Seizure disorders/developmental
disorders
Corneal diameter/biometry/IOP/IOL
power cal/gonioscopy/pachymetry
R/o NLD obstruction

33. WOUND CONSTRUCTION
◦ LENSECTOMY
◦ -Limbal route/pars plana route
◦ -limbal:preservation of bag/360 capsular
rim for secondary IOL
◦ -pars plana-2 side ports with MVR blade
◦ LENS ASPIRATION WITH PRIMARY IOL
◦ -clear corneal/scleral tunnel
◦ -2.8mm clear corneal main incision-
preferred-foldable IOLs
◦ -5.5mm scleral tunnel-rigid PMMA IOLs

34. Pre-
requisites for
ACC
Adequate pupillary dilatation
Improve visualization-use high
magnification and dim OT lights
Avoid positive vitreous pressure-
pre-op iv mannitol may be reqd
Viscolelastic-highly cohesive,use
liberally

35. Challenges –ACC
◦ A.)VERY ELASTIC CAPSULE-
◦ Deforms without tearing
◦ When it finally tears,the force of the rebound propagates the
tear rapidly and uncontrollably to the periphery
◦ B.)LOW SCLERAL RIGIDITY
◦ Positive vitreous pressure shallowing of ac anterior surface
of the lens becomes convex rhexis runs to periphery

36. C.)DIFFICULT TO USE CYSTITOME
Difficult to advance the everted capsular flap over soft cortex
Less control over rhexis tends to extend
D.)RHEXIS FORCEPS
Better control over rhexis
Utrata chances of AC shallowing as it is passed through main incision
Special end-gripping type of rhexis forceps
Introduced through side-port AC well-maintained

37. Technique-ACC
◦ INITIAL CENTRAL PERFORATION-forceps -bent 26 G needle
◦ REST OF RHEXIS
◦ Forceps only
◦ Centripetal force instead of usual tangential (ripping technique)
◦ Peformed 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
◦ Ideal size-5-5.5 mm
◦ ACC-smaller than the IOL optic diameter(6mm)

38. ◦ RHEXIS BY RIPPING
◦ Flap pulled perpendicular to rhexis edge(i.e.towards
centre)
◦ Only this method can tear the elastic capsule of children

39. Other options
◦ VITRECTORRHEXIS
◦ Cutting rate 150-300
◦ Aspiration rate 150-200cc/min
◦ 2 incision push-pull technique
◦ -2 small incisions superior & inferior
◦ -grasp the centre of flap of superior
incision & push towards centre-
semicircular tear
◦ -grasp the centre of flap of inferior incision
& pull towards centre-semicircular tear
RADIOFREQUENCY DIATHERMY
CAPSULOTOMY
High frequency current of 500khz
Platinum alloy tip probe heated to 160
F

40. Anterior capsulorrhexis
Poor visibility/total
cataracts
Shallow AC
Tendency to run off
High PP from
vitreous
Elastic anterior
capsule
Run-off

41. Irrigation and
Aspiration
Nucleus is very soft - Hence NO PHACO ENERGY needed
Bimanual/co-axial probe-faster,maintains AC and prevents hypotony,hence
pupillary miosis.
Remove entire lens matter/cortex
Polish the posterior capsule before PPC.
Membranous /calcified cataracts may require phacoemulsification

42. Primary
posterior
capsulorhexis
Indicated in children <6years
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

43. Pre-
requisites for
PPC
Excellent visibility – good
microscope,clear
cornea,sufficient mydriasis
No positive pressure

44. Technique-PPC
◦ Viscoelastic injected in capsular bag
after cortical clean up-flattens PC by
countering vitreous pressure
◦ Central perforation with cystitome in
front of retrolental space of berger

45. ◦ Central perforation
◦ -26G cystitome descends at a slant
◦ -PC engaged and punctured
◦ -small flap created by pushing margin inferiorly
◦ Small amount of viscoelastic injected into capsular hole
◦ -separates PC from vitreous
◦ -should be done slowly to avoid extension of tear to
periphery

46. ◦ Rhexis commenced with either utrata or end-
gripping forceps
◦ -proceed slowly with repeated re-grasping of the
leading edge in manner similar to anterior rhexis
◦ Rhexis size-
◦ -1.5-2mm smaller than IOL optic to reconstitute
barrier between vitreous and anterior chamber
◦ -too small or too big will prevent IOL optic capture

47. Anterior vitrectomy
Intact anterior vitreous face(AVF) acts as scaffold for lens epithelial cells
to grow-chances of VAO higher
Mandatory in infants and younger children
Maybe deferred in children >7years
Limbal/transconjuctival pars plana approach
Rates of PCO decreases only after AV not PCCC alone in children<6 years

48. CURRENT RECOMMENDATION—
Primary PCCC with AV for children <6-7 yrs of age
Primary PCCC without AV for >7 yrs of age
PC left intact in children >9-10 yrs of age

49. IOL Implantation
o Standard care-over 1 yr of age;infants-controversial?
o Single piece hydrophobic acrylic IOL in the bag;inflate
bag well with healon GV
◦ 3 piece IOL in sulcus
◦ Optic capture
◦ Bag in the lens technique

50. IOL FIXATION SITES
◦ 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
completenanterior rhexis but incomplete PCCC)
◦ Haptic in sulcus & optic in front of anterior capsule (if
incomplete anterior rhexis & PCCC)

51. Wound closure
◦ Wash all viscoelastic!
◦ Look for any peeking of rhexis/pupil-cut vitreous before wound closure
◦ LMW heparin solution(5IU in 500ml) may be used for irrigation to reduce chances of
inflammation
◦ ALWAYS suture all the wounds (low scleral rigidity-not self-sealing wound)
◦ 10-0 vicryl/10-0 monofilament nylon suture
◦ Side ports may be left unsutured in older children if well constructed and no leak at the end of
the procedure

52. Post-op management
◦ Surgery is only the first and the easiest step!
◦ Topical steroids hourly doses tapered gradually
◦ Topical antibiotics broad spectrum
◦ Topical cycloplegics
◦ Oral steroids in special cases

53. Management of aphakia
◦ SPECTACLES
◦ -B/L aphakia
◦ -most children adapt well and develop
good visual responses
◦ -poor quality of vision;increased incidence
of strabismus
◦ Poor cosmesis
◦ CONTACT LENSES
◦ -U/L and B/L aphakia
◦ -RGP/Silicone/hydrogel
◦ -better optical correction;comparable
results to primary IOL implantation
◦ -difficult to insert/costly
◦ -risk of infection/intolerence

54. Management of pseudophakia
◦ Undercorrection-less chances for higher myopic shift
and IOL exchange at later date
◦ Spectacles-given as soon as surgery is done!
◦ Single vision correction for young infants;bifocals for
toddlers;progressive glasses may be considered for
older children
◦ Secondary IOL implantation in the sulcus-for
aphakic cases @ 4-5 yrs of age

55. COMPLICATIONS
◦ Post-op inflammation(fibrin/exudates)-start oral steriods
◦ Glaucoma
◦ Posterior capsular opacification
◦ Secondary membranes
◦ Pupillary capture of IOL/IOL decentration

56. Amblyopia
◦ U/L cases most difficult to manage
◦ Starts right after surgery-aggressive part time occlusion
◦ B/L cases-check for fixation preference/BCVA at follow up visit and decide for PTO

57. THANK YOU!