Method and device for ocular alignment and coupling of ocular structures

• US 8,630,388 B2
• Filed: 01/29/2013
• Issued: 01/14/2014
• Est. Priority Date: 06/04/2007
• Status: Active Grant

• Current Assignee: Carl Zeiss Meditec Incorporated (Carl-Zeiss-Stiftung)
• Original Assignee: Oraya Therapeutics, Inc.
• Inventors: Gertner, Michael, Arnoldussen, Mark, Herron, Matt, Liang, Junzhong
• Primary Examiner(s): THOMAS, COURTNEY D
• Application Number:
  US13/753,302
• Publication Number:
  US 20130141696A1
• Time in Patent Office: 350 Days
• Field of Search: 378/65, 378/205, 606/4, 351/206, 351/246
• US Class Current: 378/65
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• CPC Class Codes: A61B 3/12 for looking at the eye fundus, e.g. ophthalmoscopes A61B3/13 takes precedence
• CPC Class Codes: A61B 3/14 Arrangements specially adapted for eye photography apparatus or arrangements for taking photographs per se G03B
• CPC Class Codes: A61B 3/152 for aligning
• CPC Class Codes: A61F 2009/00846 Eyetracking
• CPC Class Codes: A61F 2009/00863 Retina
• CPC Class Codes: A61F 9/008 using laser
• CPC Class Codes: A61F 9/00802 for photoablation
• CPC Class Codes: A61F 9/009 Auxiliary devices making contact with the eyeball and coupling in laser light, e.g. goniolenses apparatus for eye examination A61B3/0008
• CPC Class Codes: A61N 2005/1059 using cameras imaging the patient
• CPC Class Codes: A61N 2005/1091 Kilovoltage or orthovoltage range photons
• CPC Class Codes: A61N 5/1017 Treatment of the eye, e.g. for "macular degeneration"
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam

Abstract

Embodiments provide method and systems for determining or measuring objective eye alignment in an external-coordinate system so as to define a reference axis. Additional embodiments provide a method and system of aligning an objectively determined reference axis of the eye in a selected relationship to a therapeutic axis of an ophthalmic therapeutic apparatus and/or a diagnostic axis of an ophthalmic diagnostic apparatus. Embodiments provide a method and system for planning an ophthalmic treatment procedure based on objective eye alignment in an external-coordinate system so as to define a reference axis of an eye to be treated. The reference axis may be used to position a therapeutic energy component, for example, an orthovoltage X-ray treatment device, e.g., positioned to provide treatment to tissue on the retina, such as the macula.

Claims

1. A method, comprising:

determining a center of a limbus of a patient'"'"'s eye;

determining a position of a reflection of a light beam reflected from a reflective surface associated with the patient'"'"'s eye;

determining whether the position of the reflection is coincident with the center of the limbus; and

adjusting a position of the patient'"'"'s eye until the position of the reflection is coincident with the center of the limbus.

2. The method of claim 1, wherein the reflective surface associated with the patient'"'"'s eye includes one of a surface of the cornea, a surface of the lens of the eye, and the surface of the retina.

3. The method of claim 1, wherein the reflective surface associated with the patient'"'"'s eye includes one of a surface of a contact member or contact lens disposed in contact with the surface of the eye, and a surface of a mirror or fiducial element positioned on a contact member disposed in on surface of the eye.

4. The method of claim 1, wherein determining a center of a limbus includes recording an image of the patient'"'"'s limbus by an optical detector, fitting the limbus image to a circle, and determining the center point of the circle.

5. The method of claim 1, wherein the reflection from the patient'"'"'s eye is an image formed by reflection of a coherent or focused light beam off an anterior surface of a cornea of the patient'"'"'s eye.

6. The method of claim 1, further comprising providing a therapeutic beam comprising a low-energy collimated X-ray beam, the therapeutic beam being aimed along a path that intersects a region of the patient'"'"'s eye.

7. The method of claim 1, further comprising:

determining the position of an image formed by reflection of the light beam off a retina of the patient'"'"'s eye, when the position of the reflection image is coincident with the center of the limbus image,

passing a second coherent or focused light beam through the pupil of the patient'"'"'s eye to reflect off a structure of interest in the retina, and

determining the position of the image of the reflection of the second beam, relative to the image.

8. A method of defining a reference axis of a patient'"'"'s eye in an external-coordinate system, comprising

projecting a light beam, such that the light beam reflects from a reflective surface associated with the patient'"'"'s eye, forming a reflection image at the position of the reflection of the light beam;

adjusting the position of the patient'"'"'s eye until the position of the reflection image is coincident with a center of a limbus of the patient'"'"'s eye in the external-coordinate system, at which position an axis normal to a cornea at a corneal center defines a patient reference axis.

9. The method of claim 8, wherein the reference axis extends from the cornea to a position on a retina which is a maximum distance from the cornea.

10. The method of claim 8, further comprising superimposing the patient reference axis on a three-dimensional model of the eye by aligning the patient reference axis with a model reference axis.

11. The method of claim 8, further comprising positioning a beam of a diagnostic or therapeutic device at a selected position and angle with respect to the patient reference axis.

12. The method of claim 8, further comprising generating an eye-alignment signal when the patient'"'"'s eye position is aligned with an external-coordinate reference axis.

13. The method of claim 12, further comprising using the eye-alignment signal to attach an ocular positioning and stabilizing device to the patient'"'"'s eye.

14. The method of claim 13, further comprising using the eye-alignment signal to activate a therapeutic beam aimed along a path having a known relationship with the external-coordinate reference system.

15. A system of defining a reference axis of a patient'"'"'s eye in an external coordinate system, comprising

a light source for directing a light beam on a reflective surface associated with the patient'"'"'s eye,

an imaging system for recording an image of the patient'"'"'s limbus and an image formed by reflection of the light beam from a cornea of the patient'"'"'s eye, and

a processor operatively connected to the imaging system configured to, from the image of the limbus, determine the center of the limbus of the patient'"'"'s eye in the external-coordinate system.

16. The method of claim 15, wherein the processor is further configured to, from the image of the reflection of the coherent or focused light beam off the reflective surface, determine when the position of the reflection image is coincident with the center of the limbus image, at which position an axis normal to the cornea at the corneal center defines the reference axis.

17. The system of claim 15, wherein the processor is further configured to generate positioning signals for positioning a diagnostic or therapeutic device at a selected position and angle with respect to the reference axis.

18. The system of claim 15, wherein said imaging system includes a photodetector.

19. The system of claim 18, further comprising an image processor and wherein the processor operates to fit the image of the limbus to a circle, and find the center of the circle.

20. The system of claim 18, further comprising a second processor and wherein the processor operates to determine, at each eye position of the patient eye, whether the center of the patient eye limbus is the same as the position of the reflection image from the cornea.