Effects on ocular aberration and contrast sensitivity after implantation of spherical and aspherical monofocal intraocular lens - A comparative study

Purpose: Phacoemulsification with intraocular lens (IOL) implantation is the standard of care for cataractous eyes. Monofocal IOLs are spherical or aspheric. The aspheric design of IOLs reduces the spherical and higher-order aberrations and impacts contrast sensitivity post cataract surgery. There are some studies, but data in the Indian setting with the IOLs we used is lacking. We aimed to compare the effect of implantation of spheric and aspheric foldable intraocular lenses on postoperative quality of vision, spherical aberration, and contrast sensitivity. Methods: This prospective observational study was conducted at a tertiary care hospital with an ophthalmology specialty, data collection from January 2017 to May 2018 in 100 patients. Patients meeting the inclusion criteria were selected. Their preoperative and postoperative data were collected and divided into groups based on whether spherical or aspheric IOL was implanted after cataract surgery. Variables assessed were visual acuity on days 7 and 30, spherical aberrations, and contrast sensitivity was assessed at 1-month postoperative. Results: The mean age of the patients in this study was 64 +/- 8 years with a majority of patients (60%) being females. There is no significant difference in postoperative visual acuity between the two groups. Internal SA was significantly lower (-50%) in eyes implanted with aspheric IOLs (P value = 0.004, 0.0001) compared with the spherical group. Contrast sensitivity of patients of the aspheric group was significantly better (P value <0.05). Conclusion: The optical design of the aspheric IOLs reduced spherical aberrations and increased contrast sensitivity.