Comparison of the rate of refractive growth in aphakic eyes versus pseudophakic eyes in the Infant Aphakia Treatment Study

Abstract

PURPOSE To compare the rate of refractive growth between aphakic eyes and pseudophakic eyes in the Infant Aphakia Treatment Study (IATS). SETTING Twelve clinical sites across the United States. DESIGN Randomized clinical trial. METHODS Patients randomized to unilateral cataract extraction with contact lens correction versus intraocular lens (IOL) implantation in the IATS had their rate of refractive growth (RRG3) calculated based on the change in refraction from the 1-month postoperative examination to age 5 years. The RRG3 is a logarithmic formula designed to calculate the rate of refractive growth in children. Two-group t tests were used to compare the mean refractive growth between the contact lens group and IOL group and outcomes based on age at surgery and visual acuity. RESULTS Longitudinal refractive data were studied for 108 of 114 patients enrolled in the IATS (contact lens group, n = 54; IOL group, n = 54). The mean RRG3 was similar in the contact lens group (−18.0 diopter [D] ± 11.0 [SD]) and the IOL group (−19.0 ± 9.0 D) (P = .49). The RRG3 value was not correlated with age at cataract surgery, glaucoma status, or visual outcome in the IOL group. In the aphakia group, only visual outcome was correlated with refractive growth (P = .01). CONCLUSIONS Infants’ eyes had a similar rate of refractive growth after unilateral cataract surgery whether or not an IOL was implanted. A worse visual outcome was associated with a higher rate of refractive growth in aphakic, but not pseudophakic, eyes.

Heterogenicity of Congenital Cataract and Its Influence on Pseudophakic Eye Refraction Changes. Summary of the Doctoral Thesis

“…The results of all the studies prove that infants with congenital cataract after lensectomy and intraocular lens implantation during the surgery up to 2 years of age will develop myopic refraction changes at least from -4 dioptries to -10 dioptries. The present study, just in the same way as McClatchey [31], Lambert [20] and "Infant Aphakia Treatment Study" (IATS) [21], demonstrate that the earlier IOL implantation is done, the greater myopic shift develops. One should consider all benefits and shortcomings in pronounced myopic shift development cases [21; 26; 40].…”

“…Lambert et al in "Infant Aphakia Treatment Study" have drawn a conclusion that the chosen IOL power, together with the eye axial length increase and the correcting lens localisation (in a capsule bag, on retina or in the distance of glasses) affect myopic shift size. A greater IOL power will cause a greater myopic shift per one eye growth 52ontrovers [21]. In literature, however, any concrete correlation size difference in different infant age groups (2-6 months, 7-24 months) and the threshold could be found, when the correlation between myopic shift size and intraocular lens power would not be seen any more.…”

“…Different target refraction tactics can be partially equal to aphakia 52 correction with the contact correction or intraocular lens. In "Infant aphakia treatment study" it is described that in the contact lens group eye myopic shift was -6.8 D, compared to -9.66 D myopic shift in IOL group [21]. The greater myopic shift in pseudophakic eyes is associated with the higher optic power of intraocular lens.…”

“…The minimum observation/follow-up time in the current study was 6 months, the maximum -120 months, the average follow-up time was 47.8 (SD = 37.21) months or 3.9 years. In the randomised multicentre study "Infant Aphakia Treatment Study" (IATS), the USA, the eye refraction changes, complications, reoperations and vision development were compared 1 month after the operation and at the age of 5 years [21]. In "IoLunder 2" study, the association between IOL implantation and the vision acuity, secondary glaucoma like IC treatment complication was analysed 1 year after cataract surgical correction and IOL implantation [40].…”

Iedzimtas kataraktas heterogenitātes ietekme uz pseidofakiskas acs refrakcijas izmaiņām. Promocijas darba kopsavilkums

“…Mūsu pētījumā minimālais apsekošanas/novērošanas ilgums bija seši mēneši, maksimālais -120 mēneši, vidējais novērošanas ilgums bija 47,8 (SD = 37,21) mēneši jeb 3,9gadi. Randomizētajā multicentru pētījumā -"Zīdaiņu afakijas ārstēšanas pētījums" (IATS) ASV acs refrakcijas izmaiņas, komplikācijas, reoperācijas un redzes attīstība tika salīdzinātas mēnesi pēc operācijas un bērna piecu gadu vecumā[21]. "IoLunder2" pētījumā asociāciju starp IOL implantāciju un redzes asumu, sekundāru glaukomu kā IK ārstēšanas komplikāciju analizēja gadu pēc kataraktas ķirurģiskas korekcijas un IOL implantācijas [40]…”