Pattern of corneal curvature, axial length and IOL power values in children under five years withcataracts at Kikuyu eye unit
Objectives: - The aim of the study was to determine the pattern of corneal curvature, axial length and IOL power in children under five years with congenital or developmental cataracts. Design: - Retrospective case series. Setting: - The study was carried out in Kikuyu Eye Unit. Study population: - Children under five years with either unilateral or bilateral cataracts with records of axial length, keratometry and IOL power were included in the study. Children with complicated/ traumatic cataracts, microphthalmos, micro cornea and megalocornea were excluded. Study period: - January 2008 - December 2012. Materials and methods: - Data was collected using a structured questionnaire. Meansof the different measures were compared with a student t - test for a difference after adj usting for clustering within individuals for patients with bilateral cataracts. Scatterplots were then generated with an overlaid fitted linear regression line and accompanying 95% confidence interval. Results: - A total of 295 patients met the inclusion c riteria, out of these 218 had bilateral cataracts while 77 had unilateral cataracts. The median age (inter - quartile range) at surgery was 18 months, with a range of 2 - 60months. Males were the majority at 59% wh ile females constituted 41%. The males were f ound to have a longer axial length compared to the females (21.44mm v ersus 20.56mm; p<0.001). There was a rapid increase in AL in the first 2 years of 3.6mm. The females were however found to have steeper corneas than males (44.18D v ersu s 43.38D; p<0.001). IOL power needed for emmetropia in 0 - 6 months and 47 - 60 months age groups were34.00D and 24.00D respectively. Conclusion: - The greatest increase in AL is within the first two years of life . Corneal curvature probably stabilises at 6 months of age. IOL p ower needed for emmetropia decreases as the child grows older.