 A retrospective chart review was conducted, including demographics age and gender and several parameters for both the first and second eyes, including the intra-ocular lens power calculation using the HofferQ, SRKT and Holladay 1 formulas. Pentacam HR was used for pseudophakic anterior chamber depth measurement, and manual measurement was performed by a single investigator tracing a line between the anterior surface of the intra-ocular lens and the central corneal epithelium apex. Second eye refinement in the intra-ocular lens power selection for the second eye was performed using a theoretical 50 partial adjustment of the prediction error of the first eye. To relate refractive outcomes to pACD values, the investigators performed subgroup analysis based in consecutive 50μm increments in inter-ocular asymmetry of pACD 50-600. 