Evaluation of Higher-Order Corneal and Ocular AberrationsUsing the Root Mean Square (RMS ) Index with Two Soft Aspheric Lensesin Patients with LowMyopic Astigmatism

Abstract

<em><strong>Objective</strong><em> To determine which soft aspheric lens (Pure Vision or Definition AC) better modifiesthe higher-order RMS value in ocular and corneal aberrations in patients with low myopic astigmatism. <em><strong>Materials and Methodologies</strong><em> Forty eyes with myopic astigmatism were studied using alensometer with spheres no higher than -3.00 D and cylinders lower than -1.25 D, non contactlens users to whom aberrometries were performed with the COAS aberrometer and with topographerKeratron Scout at three different moments: without any contact lens, using Pure Visionand using Definition AC. <em><strong>Results</strong><em> Higher-order ocular and corneal RMS increased with bothlenses. Higher-order corneal RMS increases more with Pure Vision (16%) than with DefinitionAC (12.9%), while higher-order ocular RMS increases more with Definition AC (19%) than withPure Vision (8%). Coma aberrations were the corneal aberrations that changed the most; sphericalaberrations, on the other hand, were the ocular aberrations that experienced the most changes.Both lenses had a significant effect on the spherical aberration, diminishing it both in ocular andcorneal aberrations. <em><strong>Conclusions</strong><em> Even though both contact lenses increase the higher-orderocular and corneal RMS , Pure Vision was the lens that showed the best optical performance inthis study, as it is the one that increased higher-order ocular RMS the least.