Comparison of wavefront aberrations in rabbit and human eyes.

Background: The rabbit is one of the most common animal models used for preclinical safety evaluation of new cataract surgery and laser vision-correction technologies in ophthalmic research; however, the distributions of wavefront aberrations in rabbit eyes are unknown. The purpose of this study was to investigate the similarities and differences of wavefront aberrations between rabbit and human eyes.

Methods: Monochromatic wavefront aberrations of left and right eyes of 12 rabbits and 12 human subjects with normal vision were measured by a commercial aberrometer (WaveScan Wavefront System, Abbott Medical Optics Inc, California, USA).

Iris-based cyclotorsional image alignment method for wavefront registration.

In refractive surgery, especially wavefront-guided refractive surgery, correct registration of the treatment to the cornea is of paramount importance. The specificity of the custom ablation formula requires that the ablation be applied to the cornea only when it has been precisely aligned with the mapped area. If, however, the eye has rotated between measurement and ablation, and this cyclotorsion is not compensated for, the rotational misalignment could impair the effectiveness of the refractive surgery.

Changes in wavefront aberration with pharmaceutical dilating agents.

Purpose: Finding the best way to capture the wavefronts of small pupils for refractive surgery has become a more pressing issue as the general population ages. This study explores whether pharmaceutical dilation impacts wavefront measurement and pupil centroid.

Methods: Baseline measurements were performed on 32 eyes using the VISX WaveScan Wavefront system.

From wavefront device to laser: an alignment method for complete registration of the ablation to the cornea.

Purpose: When customized laser refractive surgery is based on a wavefront measurement, correct registration of the laser ablation to the prescribed treatment area is vital. If the treatment is not ablated exactly where it was measured, the error could negate some benefits of the procedure. Currently, treatments are aligned to the pupil center, which has been shown to shift between measurement and treatment.

Cyclotorsional eye motion occurring between wavefront measurement and refractive surgery.

Purpose: To quantify the cyclorotation occurring between wavefront measurement and laser refractive surgery.

Setting: LaserVue Eye Center Ophthalmic Clinic, Santa Rosa, California, USA.

Methods: The pupil camera of the Visx WaveScan wavefront device was used to obtain images of 51 eyes (26 patients) from 5 to 20 minutes before refractive laser surgery.

System for the design, manufacture, and testing of custom lenses with known amounts of high-order aberrations.

Now that excimer laser systems can be programmed to correct complex aberrations of the eye on the basis of wave-front measurements, a method is needed to test the accuracy of the system from measurement through treatment. A closed-loop test method was developed to ensure that treatment plans generated by a wavefront measuring system were accurately transferred to and executed by the excimer laser. A surface was analytically defined, and a Shack-Hartmann-based wave-front system was used to formulate a treatment plan, which was downloaded to an excimer laser system.