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

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

Aphakia vs Pseudophakia - Randomized Clinical Trial in Children Under 2 Years Undergoing Bilateral Congenital Cataract Surgery

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 : Primary IOL implantation. Aphakic glasses. 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.

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.

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.

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.

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.

Intraocular pressure (IOP) measured with Perkins handheld applanation tonometer. Glaucoma defined as : IOP>21 mmHg >1 occasion with any of these 3 criteria Optic nerve cupping asymmetry >0.2 cd ratio asymmetry , CD ratio >0.4 Abnormal asymmetrical axial length elongation Corneal oedema or enlargement

Corneal thickness assessed by ultrasonic pachymetry. An average of 3 values with an error less than 0.001 would be taken into account.

An Objective visual assessment to be performed using Lea Grating Paddles(Grating Acuity Test developed by Lea Hyvarinen16), Cardiff Acuity Cards(Preferential Looking Test17), or ETDRS (Early Treatment of Diabetic Retinopathy Study) chart. Vision is subjectively assessed as the ability to follow or to fixate on a point source of light or on an object shown to the child.. Ocular alignment was measured using alternative cover testing. If this kind of testing was not feasible, Hirschberg testing was performed..

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