An apparatus and method for selecting a lens that accounts for Decentration and/or Rotation Errors. The method includes obtaining results of a first wavefront exam on a patient, including a wavefront map and Zernike polynomials, selecting a first lens that improves vision, obtaining the results of a second wavefront exam including a wavefront map and Zernike polynomials, calculating the Decentration and/or Rotation Errors of the selected lens by calculating a difference between the Zernike polynomails, and selecting a second lens that better corrects accounts for the calculated Decentration and/or Rotation Errors.