Aphakia Versus Pseudophakia in Children Under 2 Years Undergoing Bilateral Congenital Cataract Surgery

• Visual axis obscuration [ Time Frame: 4 years ] [ Designated as safety issue: Yes ]
  Visual axis obscuration(VAO) assesed on slitlamp or under operating microscope in dilated pupil.VAO is defined as fibrous or proliferative cell growth leadind to a dull retinoscopic reflex.
• Glaucoma [ Time Frame: 4 years ] [ Designated as safety issue: Yes ]

  Intraocular pressure (IOP) measured with Perkins handheld applanation tonometer.

  Glaucoma defined as :

  IOP>21 mmHg >1 occasion with any of these 3 criteria

  1. Optic nerve cupping asymmetry >0.2 cd ratio asymmetry , CD ratio >0.4
  2. Abnormal asymmetrical axial length elongation
  3. Corneal oedema or enlargement
• Central Corneal Thickness [ Time Frame: 4 Years ] [ Designated as safety issue: Yes ]
  Corneal thickness assessed by ultrasonic pachymetry. An average of 3 values with an error less than 0.001 would be taken into account.

The purpose of this study is to document the safety and efficacy of primary IOL implantation in children below 2 years of age undergoing congenital cataract surgery.

The use of IOLs in pediatric patients has become increasingly popular in recent years and may represent a standard of care for older children. The refinements in surgical techniques attained in adult cataract surgery have been translated to pediatric cataract surgery to produce a technically safe eye. Nevertheless, the use of IOLs in children younger than 2 years remains controversial. Exaggerated inflammation, capsular opacification and changing refractive status of the developing eye should be considered before the use of IOLs in the first two years of life. Further more, there is concern about the unknown risks of an IOL over the long life span.

Currently, there are 3 methods of optical rehabilitation following congenital cataract surgery :

1. Primary IOL implantation.
2. Aphakic glasses.
3. Contact lenses.

At present, there is no randomized clinical trial reported to document the safety and efficacy of IOL implantation in children less than 2 years.

Aim : To compare the technical outcome (safety) and functional outcome (benefits) following primary IOL implantation and aphakia in children less than 2 years.

• Device: Intraocular Lens (Acrysof IOL)
  IOL fixation, material and size are important determinants of immediate and long-term outcome. In-the-bag fixation is the most preferred site of IOL implantation.
  Other Name: Hydrophobic Acrylic IOL
• Device: No IOL
  No IOL will be implanted in these eyes
  Other Name: No iol

• Active Comparator: Aphakia
  • The patient is randomly assigned for aphakia / pseudophakia. This is done only after vitrectomy. If it is aphakia,IOL will not be implanted.Aphakia will be corrected with aphakic glasses / contact lenses. Bilateral aphakes are given both contact lenses and glasses. So when they do not wear contact lenses they can put on aphakic glasses. Unilateral aphakes are given only contact lenses. Contact lenses should be fitted in the eye in OT immediately after the operation.
  • Aphakic glasses :

  Prescribed within 2 weeks of surgery for both eyes.

  Intervention: Device: No IOL
• Active Comparator: Pseudophakia
  The patient is randomly assigned for aphakia / pseudophakia. This is done only after vitrectomy. Hydrophobic Acrysof IOL is implanted.All pseudophakic children will be refracted and given the residual correction within a month of surgery.
  Intervention: Device: Intraocular Lens (Acrysof IOL)

Inclusion Criteria:

• Children less than 2 years
• Congenital cataract
• Bilateral cataracts
• IOL fixation - Bag/Ciliary fixated

Exclusion Criteria:

• Microphthalmos (Mean axial length 2 SDs less than normal for age)
• Microcornea (Horizontal corneal diameter <9.5 mm-asper that particular age)
• Iris coloboma
• PHPV
• Aniridia

• *Glaucoma - IOP more than or equal to 25 mmHg

  • One eyed
  • Cataract surgery already performed in fellow eye