If the surgery had the same optical effect as the patient's spectacles, then this power map would be zero everywhere. Clearly this was not the case for this patient. One component of the difference is the residual defocus and astigmatism which can be accounted by removing the second-order aberrations from the wavefront before computing the dioptric map. This result, shown in Fig. 3B , indicates that there is still a significant amount of higher-order refractive error in the outer portions of the pupil following surgery.
Units are micrometers.
Contour interval is 0.2 micrometer. Second order Zernike terms were omitted to better illustrate the change in higher-order aberrations. 3 Change in refractive power due to surgery. Second order terms removed. The shape of the post-surgical PSF for 6.0 mm pupil was typical of an optical system with positive spherical aberration.