Ellipsoidal corneal modeling for estimation and reshaping
US6505936B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 5, 2000 |
| Grant date | Jan 14, 2003 |
| Priority date | — |
| Expiry date | Oct 5, 2020 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F2009/00882
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The present invention provides apparatus and techniques for performing prolate shaped corneal reshaping using an ellipsoid corneal modeler.In accordance with the principles of the present invention, an ellipsoid corneal modeler is implemented with the well behaved conicoid, combined with a modeled surface which can be used for astigmatic treatments. An ellipsoid corneal modeler includes an ellipsoid fitter which utilizes two radii of curvature, asphericity (Q), and a surface rotation about the pupil center (roation of &thgr;), yielding the equation: Moreover, in accordance with the principles of the present invention, a target ellipsoid corneal surface with the applied refraction can be used to determine the required tissue removal for the given refractive change. This final shape will maintain the asphericity of the original corneal surface and therefore limit the spherical aberrations induced by the use of otherwise conventional techniques.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.