Corneal surgery apparatus

• US 8,523,846 B2
• Filed: 11/29/2007
• Issued: 09/03/2013
• Est. Priority Date: 11/29/2006
• Status: Active Grant

• Current Assignee: Nidek Company Limited
• Original Assignee: Nidek Company Limited
• Inventors: Makino, Hirokatsu
• Primary Examiner(s): Severson, Ryan
• Assistant Examiner(s): DANG, ANH TIEU
• Application Number:
  US12/312,814
• Publication Number:
  US 20100057059A1
• Time in Patent Office: 2,105 Days
• Field of Search: 606/4, 606/5, 606/10, 606/11, 606/12
• US Class Current: 606/4
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• CPC Class Codes: A61F 2009/00846 Eyetracking
• CPC Class Codes: A61F 2009/00872 Cornea
• CPC Class Codes: A61F 9/00804 Refractive treatments
• CPC Class Codes: A61F 9/00814 Laser features or special beam parameters therefor

Abstract

A corneal surgery apparatus which comprises a laser irradiation optical system and an eye position change detection unit comprising an illumination optical system and an image pick-up camera picking up an anterior-segment image of a patient'"'"'s eye and detecting the change in eye position based on an iris pattern in the image, and is arranged such that an irradiation position tracks movement of the eye to ablate a cornea, wherein the apparatus further comprises a contrast adjustment unit extracting a pupil portion and an iris portion based on luminance information of the image, and increasing/decreasing a set value of an illumination light amount and/or a set value of a gain of the camera to increase a contrast of the pupil portion to the iris portion and/or a contrast of the iris pattern within a range that luminance at the iris portion is not saturated.

Claims

1. A corneal surgery apparatus, which comprises:

a laser irradiation optical system capable of changing an irradiation position with a laser beam emitted from a laser source on a cornea of a patient'"'"'s eye; and

an eye position change detection unit, which comprises;

an illumination optical system arranged to illuminate an anterior-segment of the patient'"'"'s eye with infrared illumination light; and

an image pick-up camera arranged to pick up an image of the anterior-segment illuminated by the illumination optical system, and is arranged to detect change in eye position including torsion of an eyeball of the patient'"'"'s eye subjected to a surgical operation based on an iris pattern in the anterior-segment image picked up with the image pick-up camera, and is arranged such that the irradiation position with the laser beam which is applied by the laser irradiation optical system tracks movement of the patient'"'"'s eye based on a result of the detection by the eye position change detection unit, and the cornea is ablated to a desired shape by the application of the laser beam,

wherein the corneal surgery apparatus further comprises a control unit arranged to extract the iris pattern at an iris portion and a background of the iris pattern based on luminance information on the anterior-segment image picked up with the image pick-up camera, and adjust at least one of a set value of an illumination light amount of the illumination optical system and a set value of a gain of the image pick-up camera so that a luminance difference between the iris pattern and the background of the iris pattern is maximized or exceeds a predetermined reference value, and luminance at the iris pattern at the iris portion and the background of the iris pattern is not saturated.

2. The corneal surgery apparatus according to claim 1, further comprising:

a projection optical system arranged to project a visible light beam onto the patient'"'"'s eye; and

a light-amount adjustment unit comprising an operation switch with which a light amount of the projection optical system is changed manually.

3. The corneal surgery apparatus according to claim 2, further comprising:

a setting unit arranged to set an allowable range of variation of a pupil size such that the iris pattern is detectable, the iris pattern being used as a reference for tracking the patient'"'"'s eye; and

a display control unit comprising a display unit arranged to display the anterior-segment image picked up with the image pick-up camera, and is arranged to display a mark indicating the allowable range, which is set by the setting unit, in a manner of being superimposed on the anterior-segment image displayed on the display unit.

4. A corneal surgery apparatus, which comprises:

a laser irradiation optical system capable of changing an irradiation position with a laser beam emitted from a laser source on a cornea of a patient'"'"'s eye; and

an eye position change detection unit, which includes;

an illumination optical system arranged to illuminate an anterior-segment of the patient'"'"'s eye with infrared illumination light; and

an image pick-up camera arranged to pick up an image of the anterior-segment illuminated by the illumination optical system, and is arranged to detect change in eye position including torsion of an eyeball of the patient'"'"'s eye subjected to a surgical operation based on an iris pattern in the anterior-segment image picked up with the image pick-up camera, and is arranged such that the irradiation position with the laser beam which is applied by the laser irradiation optical system tracks movement of the patient'"'"'s eye based on a result of the detection by the eye position change detection unit, and the cornea is ablated to a desired shape by the application of the laser beam,

wherein the corneal surgery apparatus further comprises a control unit arranged to extract the iris pattern at an iris portion and a background of the iris pattern based on luminance information on the anterior-segment image picked up with the image pick-up camera, and adjust at least one of a set value of an illumination light amount of the illumination optical system and a set value of a gain of the image pick-up camera so that a luminance difference between the iris pattern and the background of the iris pattern is maximized or exceeds a predetermined reference value, and luminance at the iris pattern at the iris portion and the background of the iris pattern is not saturated;

a projection optical system arranged to project a visible light beam onto the patient'"'"'s eye;

a setting unit arranged to set an allowable range of variation of a pupil size such that the iris pattern is detectable, the iris pattern being used as a reference for tracking the patient'"'"'s eye; and

a light-amount adjustment unit arranged to determine whether or not the pupil size detected by the eye position detection unit goes beyond the allowable range during the surgical operation, and automatically adjust the light amount of the projection optical system based on a result of the determination.