Purpose:To compare the visual outcomes and complications of three different types of phakic intraocular lenses (PIOLs), for correction of moderate to high myopia.Methods:We reviewed 112 myopic eyes undergoing PIOL implantation using Artisan (40 eyes), Artiflex (36 eyes), and implantable collamer lens (ICL, 36 eyes). Best corrected visual acuity (BCVA), intraocular pressure (IOP), pachymetry, corneal endothelial cell (CEC) loss, and higher order aberrations (HOA) were compared.Results:Mean follow-up period was 30 ± 11 months. Preoperatively, spherical equivalent (SE) refractive error was −11.6 ± 3.7, −9.59 ± 1.97, and −12.3 ± 4.8 D in the Artisan, Artiflex and ICL groups, respectively. SE was comparable among the study groups at final follow-up (P = 0.237). Mean astigmatic reduction was 0.31 ± 0.72, 0.45 ± 0.62, and 0.0 ± 0.57 in the Artisan, Artiflex and ICL groups, respectively (P = 0.007). Emmetropia (±1 D) was achieved in 60%, 91.7% and 77.8% of eyes in the Artisan, Artiflex and ICL groups, respectively, the difference was significant between the Artisan and Artiflex groups (P = 0.017). BCVA improvement more than one line occurred in 25%, 19.4% and 38.9% of eyes (P = 0.158); pachymetric changes were minimal with no difference among the three groups (P = 0.754), and mean CEC loss was 10 ± 9%, 9 ± 6% and 9 ± 10% in the Artisan, Artiflex and ICL groups, respectively (P = 0.694). HOAs (P = 0.039), vertical trefoil (P = 0.032) and spherical aberration (P = 0.001) were higher with Artisan group as compared to ICL. Total aberrations (P = 0.028) and spherical aberration (P = 0.001) was also higher with Artisan group as compared to Artiflex.Conclusion:Visual and refractive outcomes were comparable with Artisan, Artiflex and ICL. In terms of HOAs and quality of vision, ICL and Artiflex seem to be better choices in highly myopic eyes.

Graft biomechanics seem to be closer to normal values with larger grafts and greater donor-recipient disparity. These metrics had a significant correlation with IOP GAT after PKP.

DALK using the big-bubble technique for keratoconic eyes provides corneal biomechanics comparable to PK.

Using numerical simulations of the time-dependent Schrödinger equation, we study the full quantum dynamics of the motion of an atomic ion in a linear Paul trap. Such a trap is based on a time-varying, periodic electric field, and hence corresponds to a timedependent potential for the ion, which we model exactly. We compare the center of mass motion with that obtained from classical equations of motion, as well as to results based on a time-independent effective potential. We also study the oscillations of the width of the ion's wave packet, including close to the border between stable (bounded) and unstable (unbounded) trajectories. Our results confirm that the center-of-mass motion always follow the classical trajectory, that the width of the wave packet is bounded for trapping within the stability region, and therefore that the classical trapping criterion are fully applicable to quantum motion.

We present a program to simulate the dynamics of a wave packet interacting with a time-dependent potential. The time-dependent Schrödinger equation is solved on a one-, two-, or three-dimensional spatial grid using the split operator method. The program can be compiled for execution either on a single processor or on a distributed-memory parallel computer. Keywords Nature of problem:Solves the time-dependent Schrödinger equation for a single particle interacting with a time-dependent potential. Solution method:The wave function is described by its value on a spatial grid and the evolution operator is approximated using the split-operator method [4, 5], with the kinetic energy operator calculated using a Fast Fourier Transform. Restrictions:Unusual features: Simulation can be in one, two, or three dimensions. Serial and parallel versions are compiled from the same source files. Additional comments:Running time: Strongly dependent on problem size. References