Comparison of Visual Acuity, Contrast Sensitivity and Spherical Aberration after Implantation of Aspheric and Spheric Intraocular Lenses

To compare visual outcome of aspheric and spheric intraocular lenses (IOLs) implantation in patients with age-related cataract in terms of visual acuity (VA), contrast sensitivity (CS) and spherical aberration In this prospective randomized interventional study, 59 consecutive cases of senile cataract who had been admitted for cataract surgery to Farabi Eye Hospital, Tehran, Iran between June 2008 and July 2010 were recruited. Patients were randomly assigned to two treatment groups using computerized software; eyes were implanted with either a aspheric or spheric IOLs (Acrylic, Lens Tec Co, Tehran, Iran). Pre and postoperatively, patients underwent complete ocular examination and their uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) were measured. Three months after the operation patients were visited to measure spherical aberration and CS. Fifty-two patients with the mean age of 55.7±5.9 years (range, 45-73 years) remained for surgical interventions. Postoperative UCVA and BCVA did not show a significant difference between our two study groups (P=0.124 and 0.400, respectively). Spherical aberration after cataract surgery in pseudophakic situation and pupil diameter of 5 mm was significantly lower in eyes with aspheric IOLs compared to spherical ones (0.22±0.10 vs. 0.30±0.12 µ, respectively, P=0.03). CS in all frequencies was better in aspheric IOLs compared to the spheric ones and except to the frequency of 20 cpd this difference was statistically significant (P<0.05). Although both aspheric and spheric IOLs resulted into a favorable VA, aspheric IOLs lead to better visual performance through a lower spherical aberration and better CS and quality of vision. However intraindividualization of asphericity by individual IOL surface design may be the best future option.