Abstract
Abstract: :
Background: Axial elongation in known to cause refractive changes after pediatric lens surgery. Controversial results about the refractive shift in pseudophakic and aphakic eyes have been published. Purpose: to evaluate the influence of various factors on the refractive changes. Methods: Retrospective analysis of 66 children (99 eyes) who underwent cataract surgery. Causes for surgery were congenital/developmental (68), traumatic (13), secondary (5) cataract or subluxation (13) of the lens. Extracapsular lens aspiration was performed and IOL were implanted in 31 eyes. The median age at the time of surgery was 5 (0,5–128) months for patients left aphakic and 59 (27–116) mo for pseudophakic children. Patients were followed for a minimum of 6 (median 43, 6–160) mo. The refractive shift of each pseudophakic eye was compared to the predicted change according to a logarithmic model based on biometric data of normal children. Results: 84% of the children could cooperate with acuity tests, visual acuities of 20/40 or better were achieved in 41% of eyes. The average refractive shift (spherical equivalent, +/– standard deviation) is presented for each ethiologic group. Aphakia: –3,8 +/– 5.0 dpt over a mean of 49 mo for congenital/developmental cataracts, –1,0 +/– 7,8 dpt over a mean of 73 mo for traumatic cataracts and –2,6 +/– 3,6 dpt over a mean of 44 mo for secondary cataracts. Patients operated on before the age of 6 years had a higher average myopic shift than older children. Pseudophakia: –0,5 +/– 2,8 dpt over a mean of 25 mo for congenital/developmental cataracts, –1,3 +/– 1,0 dpt over a mean of 21 mo for traumatic cataracts, +1,2 +/– 2,7 dpt over a mean of 35 mo for secondary cataracts and +1,2 +/– 2,2 dpt over a mean of 43 mo for subluxation. The mean refractive change was lower than predicted (+0,3 vs. –1,6 dpt) for all age groups and some children even had a hyperopic shift. Conclusions: Pseudophakia and aphakia in children result in considerable refractive changes. Aphakic children tend to have a decrease in hyperopia over time. There is much variability in the postoperative refractive changes and predicting it accurately remains difficult. Our average data suggest that IOL implantation has a retarding effect on the myopic shift, especially in eyes with accompanying defects.
Keywords: cataract • infant vision • refraction