Abstract
Abstract: :
Purpose: To evaluate post-excimer spherical aberration in eyes treated with the Nidek NAVEX custom ablation strategy. Methods: 50 eyes, with a preoperative spherical equivalent of -4.57D±0.83D underwent treatment with the NAVEX software and the Nidek EC 5000 laser. Results: Six months postoperatively, all eyes were within 0.25D of aim, and BSCVA was 20/16 or better in 100% of the eyes. Higher order aberrations did not show an increase postoperatively when tested at 3.0-mm or 5.0-mm pupils, and there was only a slight increase for a 7.0-mm pupillary diameter. Topographic and aberrometric analysis showed that the postoperative functional optical zone (OZ) had a larger diameter than the ablated zone. All eyes displayed OZs with a smooth (low-dioptric-gradient) transition to the untreated cornea. Conclusions: Custom ablation with the NAVEX system decreased postoperative spherical aberration by increasing the functional OZ. The absence of steep dioptric gradients in the periphery of the ablated area made that increase of the functional OZ possible.
Keywords: refractive surgery • refractive surgery: comparative studies • refractive error development