Tilt and decentration of bag-fixated intraocular lenses: a comparative study between capsulorhexis and envelope techniques.

Malposition of an intraocular lens (IOL) may cause symptoms such as glare, halos, and other visual aberrations. The purpose of this study is to determine the effect of two different anterior capsulotomy techniques on IOL tilt and decentration. Bag-fixated IOL implantation after uncomplicated extracapsular cataract extraction was performed using both envelope (65 eyes) and continuous circular capsulorhexis (CCC) technique (42 eyes). Eyes were followed-up at least 6 months postoperatively. While the mean IOL decentration after envelope technique was found to be 0.65 mm, this was 0.15 mm after CCC technique. On the other hand, the mean actual tilting angle of IOL after envelope technique was 5.66 degrees, whereas this was 1.13 degrees after CCC technique. The aforementioned differences were statistically significant (p < 0.01, and p < 0.01). Furthermore, in 17 eyes (26.1%) where envelope technique and in 29 (69.0%) eyes where CCC technique was used demonstrated no IOL tilt and decentration. This study shows that the CCC technique may result in less optical problems due to IOL malposition compared to the envelope technique.