Cataracts in Paediatric patients (With acknowledgements to the Online Journal of Ophthalmology: www.onjoph.com)

Introduction Opacity in lens Can be: Visually significant or not Stable or Progressive Congenital or Acquired Unilateral or Bilateral Partial or Complete Congenital: incidence 6/10 000 10% of childhood blindness

Classification : Acquired cataracts Systemic diseases : Diabetes mellitus : Myotonic dystrophy : Atopic dermatitis : Neurofibromatosis 2 Ocular diseases : Chronic anterior uveitis : High myopia : Fundus dystrophies eg Retinitis pigmentosa Drugs : Corticosteroids : Chlorpromazine Trauma : Blunt : Sharp

Congenital cataracts: Bilateral Genetic Mutation : Autosomal Dominant Metabolic : Galactosaemia : Lowe : Hypoparathyroidism : Fabry Infective : TORCH organisms Chromosomal : Trisomy 21 (Down) : Trisomy 18 (Edward) : Trisomy 13 (Patau) Skeletal : Hallerman-Streiff : Nance-Horan Ocular anomalies : Aniridia : Anterior segment dysgenesis syndrome Idiopathic : in 50%

Congenital cataracts: Unilateral Sporadic, no family history Ocular anomalies : Persistent foetal vasculature Cause identified in only 10%

Morphology : Examples

Evaluation Screen newborns with red reflex test History : Family Maternal infections Examination: systemic diseases or syndromes Workup: Bilateral cases without known hereditary basis TORCH screen s-glucose s-calcium, phosphate Urine: reducing substances (galactosaemia) amino acids ( Lowe syndrome) haematuria (Alport syndrome)

Ocular examination Formal estimate of vision not possible in neonate Special tests: Preferential looking test, visually evoked potentials Density and position of cataract Morphology Associated ocular pathology Indicators of severe visual impairment : No fixation Nystagmus Strabismus

The visually significant cataract In central visual axis, bigger than 3mm Posterior cataract No clear zones in between Retinal details not visible with direct ophthalmoscope Nystagmus or strabismus present Poor central fixation after 8 weeks

Treatment Surgery: Cataract extraction and intraocular lens implantation for visually significant cataract By 6 weeks of age Bilateral cases: 1 week apart Non visually significant cases : careful observation, possible pupillary dilation

Considerations regarding surgery Intraocular lens : Power of lens – Myopic shift of the growing eye Surgical technique Postoperative intraocular inflammation (uveitis) Glaucoma and retinal detachment may develop

Pseudophakic eye

Postoperative considerations Clear vision for distance and near Intraocular lens: regular refraction Spectacles Contact lenses Treatment of amblyopia : Occlusion therapy

Conclusion: Congenital cataracts Correct management essential to prevent permanent visual loss Team effort ophthalmologist, paediatrician, geneticist,family Early detection within the first month of life is very important Knowledge of systemic conditions associated with cataract