Bi-radial patient interface

Abstract

A patient interface for an ophthalmic system can include an attachment portion, configured to attach the patient interface to a distal end of the ophthalmic system; a contact portion, configured to dock the patient interface to an eye; and a contact element, coupled to the contact portion, configured to contact a surface of a cornea of the eye as part of the docking of the patient interface to the eye, and having a central portion with a central radius of curvature Rc and a peripheral portion with a peripheral radius of curvature Rp, wherein Rc is smaller than Rp.

1 . A method of docking a patient interface of an ophthalmic surgical laser system to an eye, the method comprising:
 determining R(central-cornea), a radius of curvature of a central portion of a cornea of the eye, and R(peripheral-cornea-sclera), a radius of curvature characteristic of a peripheral portion of the cornea and a sclera of the eye;   selecting a contact element with a central portion having a central radius of curvature Rc and a peripheral portion having a peripheral radius of curvature Rp that is greater than Rc, wherein
 Rc is less than R(central-cornea)+1 mm, and 
 Rp is less than R(peripheral-cornea-sclera)+1 mm; and 
   docking the patient interface of the ophthalmic surgical laser system with the selected contact element to the eye.   
     
     
         2 . The method of claim  22 , the selecting comprising:
 selecting a contact element, wherein
 Rc is less than R(central-cornea)+0.5 mm, and 
 Rp is less than R(peripheral-cornea-sclera)+0.5 mm. 
   
     
     
         3 . The method of claim  22 , the selecting comprising:
 selecting the contact element with Rc less than R(central-cornea).   
     
     
         4 . The method of claim  22 , wherein:
 the selected contact element is inserted into the patient interface before docking.   
     
     
         5 . The method of claim  22 , the selecting comprising:
 selecting the patient interface from a set of patient interfaces that has the selected contact element.   
     
     
         6 . The method of claim  22 , the determining comprising:
 generating an image of an anterior portion of the eye; and   determining R(central-cornea) and R(peripheral-cornea-sclera) from the image.   
     
     
         7 . The method of claim  27 , the generating comprising:
 generating a depth-image with at least one of an Optical Coherence Tomography system, a Scheimpflug system and a slit lamp system.