Carl Zeiss Gmbh

Humphrey Instruments Incorporated

Allergan Humphrey

Alan R Kirschbaum

Donald E Lehmer

David E Huang

Jay Wei

Christopher L Petersen

Embodiments of the present invention provide method and apparatus for diagnosing and monitoring eye disease such as, for example, glaucoma. In particular, embodiments of the present invention analyze OCT scans of a retina to determine one or more of the following measures for diagnosing and monitoring glaucomatous retinal nerve fiber layer (&ldquo;NFL&rdquo;) change: an NFL thickness; a ratio of NFL thickness in a vertical quadrant (superior and inferior quadrants in an OCT scan are combined in a vertical average) and a horizontal quadrant (nasal and temporal quadrants in the OCT scan are combined in a horizontal average); and an NFL signal ratio (&ldquo;NSR&rdquo;) of a sum of signal strengths in a predetermined portion of the NFL and a sum of signal strengths in a predetermined region below a retina-pigment epithelium (&ldquo;RPE&rdquo;) interface.

Method and apparatus for diagnosing and monitoring eye disease

An embodiment of the present invention is a refractively corrected, wavelength selective, transparent visual field test occluder for a non-tested eye used in a visual field testing apparatus which uses a stimulus that produces light in a first color spectral range and a background illumination that produces light in a second color spectral range, the visual field test occluder comprising: (a) a base; (b) a fastener configured to fasten the base over a subject's eye; (c) a mounting affixed to the base configured to hold a filter and a refractive lens; and (d) a filter held in the mounting; wherein the filter substantially prevents transmission of light in the first color spectral range and substantially transmits light in the second color spectral range.

Refractively corrected, wavelength selective, transparent occluder for a

Embodiments of the present invention are method and apparatus for measuring the size and position of an eye's pupil, and for doing so rapidly. In particular, embodiments of the present invention are methods and apparatus for determining pupil size and position without measuring the fall pupil and for doing so rapidly, in real time, as data are being collected. An embodiment of the present invention is a method for determining a size of an eye's pupil which comprises the steps of: (a) storing reference partial areas for a reference pupil that are associated with scan lines of a two-dimensional image of the eye; (b) analyzing one or more scan lines comprised of pixels from another two-dimensional image of the eye as follows: (c) determining of which the pixels in an analyzed scan line are in the pupil; (d) determining a sum of such pixels for the analyzed scan line; (e) determining a partial area corresponding to the scan line by adding the sum to the partial area for previously analyzed scan lines; and (f) estimating the size of the pupil from the partial areas determined from the another two dimensional image and the partial areas for the reference pupil. Further, the inventive and apparatus utilizes an iterative estimation procedure that may be terminated whenever successive estimates satisfy a predetermined convergence criterion.

Method and apparatus to measure pupil size and position

Apparatus for gaze tracking an eye utilizing short coherence length interferometry, also known as optical coherence tomography ('OCT'). An embodiment of the present invention is an apparatus for gaze tracking an eye which includes: (a) an optical coherence tomography (OCT) apparatus; (b) a scanning apparatus for scanning across a predetermined portion of the eye with optical output from the OCT apparatus; (c) an analysis apparatus for analyzing detection signals output from the OCT apparatus to determine a location of a feature of the eye; (d) an illumination apparatus for producing a reflection of radiation from a cornea of the eye (corneal reflex); (e) a detection apparatus for determining a location of the corneal reflex; and (f) the analysis apparatus further includes an apparatus which is responsive to the location of the feature and to the location of the corneal reflex for gaze tracking.

Gaze tracking using optical coherence tomography

A field test apparatus and method is disclosed in which gradual movement of the head supporting chin cup is used to maintain a centered relation between the eye being tested and the trial lens frame holding the required prescription for optimum vision of the patient. During the test, alternating illumination is provided in the infrared between a central corneal reflection and an iris illuminating source which imparts a high contrast bright circular iris image surrounding a central dark pupil. Content addressable memories are used to delineate areas of contrast change for rapid and abbreviated microprocessor analysis of conventional RAM images. Both the corneal reflection image--which is a brightly illuminated spot on an otherwise dark background--and the pupillary image--which is a dark pupil surrounded by a brightly illuminated high contrast image of the iris are approximately located at their boundaries using content addressable memory. Thereafter, conventionally stored video data is processed at locations restricted to the high contrast boundaries. For location of the pupil center, special techniques are disclosed for examining the image's first and second derivatives to establish the pupil center within sub-pixel limits. These methods include sufficient data processing speed improvements to enable a time shared use of a microprocessor having gaze angle measurement as a peripheral event to instrument control, and data collection required in such field testing.

Field tester gaze tracking using content addressable memories to improve

A field test apparatus is disclosed which is interactive both in the automated positioning of trial lenses (used to correct the patient's focal distance to the tester hemispherical projection screen) as well as providing automatic gaze direction determination through automated video surveillance of the patient's eye. A moveable trial lens holder is provided. This trial lens holder is remotely moveable horizontally and vertically and carries light sources for illuminating the eye preferably in the infrared spectrum at oblique angles preferably towards the center of the eye from the periphery of the trial lens holder. In the gaze direction determination system, a gaze direction determination infrared source--preferably on the surface of the screen near the center of the screen--generates a gaze direction determination reflection on the cornea of the eye--this reflection being near the apex of a normal spherical cornea. At the same time, provision for the automated video measurement of the center of the eye pupil is provided--preferably including measuring a horizontal chord of the eye pupil, bisecting this horizontal chord, locating the bottom of the eye pupil along the bisected dimension, and thereafter finding the pupil center. The relative position of the gaze direction determination reflection from the cornea and the center of the pupil is necessarily related to the direction of gaze of the eye. This relative position is compared to the relative position that the patient initially had when properly fixated. Change in this comparison value is utilized to indicate a change in gaze direction.

Growing community of inventors

Oakland, CA, United States of America

Alan R Kirschbaum