Materials and Methods: Three hundred eighty seven patients undergoing phacoemulsification between May 2000 and May 2002 were included in the study. Types and number of implanted IOLs were: AR40 (hydrophobic acrylic /Allergan) in 102 eyes, SI40 (Silicon/ Allergan) in 68 eyes, Acrysof (hydrophobic acrylic / Alcon) in 57 eyes, CeeOn (silicon /Pharmacia) in 28 eyes, Softec (hydrophilic acrylic/Lenstec) in 72 eyes, and PS52 (PMMA, Allergan) in 60 eyes. Dioptries of IOLs were calculated with SRK II formula using A scan biometry (Mentor, USA). Differences between autorefractometry values measured preoperatively and postoperatively after one month were determined. Refractive shifts obtained for different IOL types were statistically compared using analysis of variance (ANOVA) and posthoc test.

Results: The refractive shifts determined were as following: -0.53 D in AR40 group, -0.43 D in SI40 group, -0.27 D in Acrysof group, -0.83 D in Softec group, -0.56 D in CeeOn group, and +0.26 in PMMA group. Refractive change was between -3.00 and +2.00 D. There was no statistically significant difference among the IOL groups except PMMA group.

Conclusion: All of the IOL types studied have similar spherical refractive change after uneventful phacoemulsification with in the bag IOL implantation. Although Acrysof induced less spherical refractive change, all IOL types except PMMA caused relatively small and reasonable myopic shift compared with preoperative spherical refraction. Keywords : Spheric refractive schift, Intraocular lens, phacoemulsification