Adaptive photoscreening system

• US 7,878,652 B2
• Filed: 09/22/2008
• Issued: 02/01/2011
• Est. Priority Date: 01/24/2006
• Status: Active Grant

• Current Assignee: University of Tennessee Research Foundation (University of Teesside)
• Original Assignee: University of Tennessee Research Foundation (University of Teesside)
• Inventors: Lewis, James W. L., Chen, Ying-Ling Ann
• Primary Examiner(s): Mai; Huy K
• Application Number:
  US12/234,947
• Publication Number:
  US 20090079937A1
• Time in Patent Office: 862 Days
• Field of Search: 351/200, 351/205, 351/206, 351/210, 351/222, 351/246, 351/221
• US Class Current: 351/206
• CPC Class Codes: A61B 3/0008 provided with illuminating means A61B3/117 takes precedence; goniolenses used for laser treatment A61F9/009; illuminating means for optical instruments G02B27/00
• CPC Class Codes: A61B 3/08 for testing binocular or stereoscopic vision, e.g. strabismus
• CPC Class Codes: A61B 3/103 for determining refraction, e.g. refractometers, skiascopes
• CPC Class Codes: A61B 3/1035 for measuring astigmatism testing astigmatism A61B3/036
• CPC Class Codes: A61B 3/112 for measuring diameter of pupils
• CPC Class Codes: A61B 3/145 by video means

Abstract

Briefly described, one embodiment of the system, among others, can be implemented as follows. The system includes a computer control system and an environmental light source that is controlled by the computer control system such that an amount of light provided by the environmental light source is adjusted by the computer control so that ocular parameters of an examinee are within a targeted range. Further, the system includes an irradiation system that provides multiple angle and axial eccentricity illuminations and selective wavelength irradiation based upon instructions received from the computer control system, wherein the computer control system instructs the irradiation system to provide different irradiation characteristics for different screening procedures. Also, the system includes an image detection system that captures ocular images of the examinee, wherein the computer control system analyzes captured images and provides results of in-situ analysis. Other systems and methods are also provided.

Claims

1. A system of automatic computer analysis for photoscreening system that comprises:

a strabismus module that analyzes ocular fixation and motility;

a single-eye module that analyzes abnormalities of each single eye; and

an eye-correlation module that compares differences of retinal reflex between two eyes, wherein the strabismus module determines an examinee'"'"'s convergence and fixation angle; and

compares the examinee'"'"'s convergence and fixation angle with regions of normal, abnormal, and uncertain results to indicate whether a captured ocular image shows an abnormality related to strabismus.

2. A system of automatic computer analysis for photoscreening system that comprises:

a strabismus module that analyzes ocular fixation and motility;

a single-eye module that analyzes abnormalities of each single eye; and

an eye-correlation module that compares differences of retinal reflex between two eyes, wherein the single-eye module analyzes retinal reflex of each eye in each of the following areas;

intensity spatial distribution and gradient of each spectral region of interest;

uniformity; and

spectral distribution; and

compares signals at regions of interest against predetermined thresholds.

3. The system of claim 2, wherein each pupil image is separated into red, green and blue panels.

4. The system of claim 2, wherein the intensity gradient is along an eccentricity direction of a camera-light alignment.

5. A system of automatic computer analysis for photoscreening system that comprises:

a strabismus module that analyzes ocular fixation and motility;

a single-eye module that analyzes abnormalities of each single eye; and

an eye-correlation module that compares differences of retinal reflex between two eyes, wherein the eye-correlation module compares difference between a left and right eye in each of the following areas;

intensity of spectral region of interest;

uniformity;

intensity gradient and distribution; and

spectrum ratios, regions of interest being compared against predetermined thresholds.

6. The system of claim 5, wherein the spectrum ratios include red, green and blue spectrum ratios.

7. The system of claim 5, wherein the intensity gradient is along an eccentricity direction of a camera-light alignment.

8. A method of performing optical opacity examination of an eye comprising:

utilizing a photoscreening technique employing co-axial infrared radiation under a dimmed lighting environment to screen the eye for optical opacity.

9. A method of performing cornea and keratoconus examination comprising:

utilizing an eccentric photoscreening technique with a sequent pulsed infrared radiation under a dimmed lighting environment to obtain sequenced images to screen for cornea abnormality and keratoconus.

10. A method of performing retinal examination comprising:

utilizing a co-axial photoscreening method providing co-axial irradiation to illuminate a subject with a broad band spectral radiation and an image detection system that detects signals in multiple wavelength regions under a dimmed lighting environment generated by the co-axial irradiation to screen for retinal abnormality.

11. A method of determining ocular spherical and cylindrical refractive errors from a video photoscreening system comprising:

utilizing a ratio of integrated intensities obtained from multiple images that correspond to various eccentricities illumination in determining ocular spherical and cylindrical refractive errors.

12. A method of determining ocular refractive error from a retinal reflex of a photoscreening image comprising:

utilizing information of ocular orientation obtained from a corneal reflection position to determine ocular refractive error.

13. A photoscreening method comprising:

analyzing ocular fixation and motility of a subject;

analyzing abnormalities of each single eye of the subject by analyzing retinal reflex of each eye of the subject in each of the following areas;

intensity spatial distribution and gradient of each spectral region of interest;

uniformity; and

spectral distribution; and

comparing signals at regions of interest against predetermined thresholds; and

comparing differences of retinal reflex between two eyes of the subject.

14. A photoscreening method comprising:

analyzing ocular fixation and motility of a subject;

analyzing abnormalities of each single eye of the subject; and

comparing differences of retinal reflex between two eyes of the subject by comparing difference between a left and right eye of the subject in each of the following areas;

intensity of spectral region of interest;

uniformity;

intensity gradient and distribution; and

spectrum ratios, regions of interest being compared against predetermined thresholds.

15. A system of automatic computer analysis for photoscreening system that comprises:

an irradiation system that provides multiple angle and axial eccentricity illuminations; and

a computer control system that generates a three-dimensional bell-shape intensity profile based on the multiple angle and axial eccentricity illuminations that is used to detect possible ocular refractive errors and astigmatism of a subject being examined.

16. A photoscreening method comprising:

providing multiple angle and axial eccentricity illuminations used during photoscreening examination of a subject; and

generating a three-dimensional bell-shape intensity profile based on the multiple angle and axial eccentricity illuminations that is used to detect possible ocular refractive errors and astigmatism of the subject being examined.

17. A system of automatic computer analysis for photoscreening system that comprises:

a strabismus module that analyzes ocular fixation and motility;

a single-eye module that analyzes abnormalities of each single eye; and

an eye-correlation module that compares differences of retinal reflex between two eyes, further comprising;

a display for showing a target that moves across the display;

a visual occluder that limits a subject'"'"'s ability to view the target with both eyes at different points during the target'"'"'s trajectory across the display; and

a computer control system that detects whether an eye of the subject experiences saccade scattering as the subject is visually tracking the target across the display and determines the subject'"'"'s Hirschberg ratio and fovea angle based on the subject'"'"'s gazing trajectory, the gazing trajectory being measured by the computer control system.

18. The system of claim 17, wherein the visual occluder comprises a frame that produces temple side boundaries through which the subject views the target.

19. The system of claim 17, wherein the visual occluder comprises a nasal occluder having a nasal-side boundary about which the subject views the target.

20. The system of claim 17, wherein the visual occluder comprises binocular tubes having a nasal-side boundary about which the subject views the target.

21. A photoscreening method comprising:

analyzing ocular fixation and motility of a subject by determining a subject'"'"'s convergence and fixation angle and comparing the subject convergence and fixation angle with regions of normal, abnormal, and uncertain results to indicate whether a captured ocular image shows an abnormality related to strabismus;

further comprising;

displaying a target in motion across a display;

limiting a subject'"'"'s ability to view the target with both eyes at different points during the target'"'"'s trajectory across the display;

measuring the subject'"'"'s gazing trajectory as the subject visually tracks movement of the target across the display; and

determining the subject'"'"'s Hirschberg ratio and fovea angle based on the subject'"'"'s gazing trajectory.

22. The method of claim 21, further comprising analyzing abnormalities of each single eye of the subject and comparing the differences of retinal reflex between two eyes of the subject.