Device and method for optical imaging of retinal function

• US 20040075812A1
• Filed: 01/17/2003
• Published: 04/22/2004
• Est. Priority Date: 01/18/2002
• Status: Active Grant

• Current Assignee: Kestrel Corp., The Research Foundation for The State University of New York (State University of New York), University of Iowa Research Foundation
• Original Assignee: University of Iowa Research Foundation
• Inventors: Kwon, Young H., Soliz, Peter, Tso, Daniel, Kardon, Randy H.
• Granted Patent: US 7,118,217 B2
• Time in Patent Office: Days
• US Class Current: 351/206
• CPC Class Codes: A61B 3/0058 for multiple images
• CPC Class Codes: A61B 3/12 for looking at the eye fundus, e.g. ophthalmoscopes A61B3/13 takes precedence
• CPC Class Codes: A61B 5/14555 specially adapted for the eye fundus

Abstract

An Optical Imaging Device of Retinal Function has been developed to detect changes in reflectance of near infrared light from the retina of human subjects in response to visual activation of the retina by a pattern stimulus. The measured changes in reflectance correspond in time to the onset and offset of the visual stimulus in the portion of the retina being stimulated. Any changes in reflectance can be measured by interrogating the retina with a light source. The light source may be presented to the retina via the cornea and pupil or through other tissues in and around the eye. Different wavelengths of interrogating light may be used to interrogate various layers of the retina. Additionally, various novel patterns and methods of stimulation have been developed for use with the imaging device and methods.

Claims

1. An apparatus for the functional imaging of a retina comprising:

a. a stimulation source positioned with respect to the retina;

b. a retinal interrogator constructed and arranged to emit light in the direction of the retina and along an optical path; and

c. a detector constructed and arranged to detect the light emitted from the retinal interrogator and reflected from the retina;

d. wherein the retinal interrogator is constructed and arranged to emit light in a plurality of wavelengths.

2. The apparatus of claim 1, wherein the stimulation source is constructed and arranged to be selectively disabled.

3. The apparatus of claim 1, wherein the retinal interrogator is positioned to transmit light through a sclera.

4. The apparatus of claim 3, wherein the retinal interrogator is mounted on a contact lens.

5. The apparatus of claim 1, wherein the retinal interrogator is constructed and arranged to transmit light through a lower eyelid.

6. The apparatus of claim 1, wherein the retinal interrogator is constructed and arranged to transmit light through an inferior orbital area.

7. The apparatus of claim 1, wherein the retinal interrogator is constructed and arranged to emit light in a range of near infrared wavelengths.

8. The apparatus of claim 1, wherein the retinal interrogator is constructed and arranged to emit light in a range of infrared wavelengths.

9. The apparatus of claim 1, wherein the retinal interrogator comprises at least one light emitting diode.

10. The apparatus of claim 1, wherein the detector comprises at least one CCD sensor.

11. The apparatus of claim 1, further comprising an Allen dot placed in the optical path.

12. A method for stimulating a functional signal in a retina comprising the steps of:

a. recording a baseline retinal response;

b. applying a stimulus to the retina during a stimulus phase;

c. recording a retinal response during the stimulus phase; and

d. computing a relationship of the baseline response to the stimulus response.

13. The method of claim 12, further including the step of applying a stimulus to the retina while recording the baseline retinal response.

14. The method of claim 13, wherein the step of recording the baseline retinal response comprises the application of a diffuse luminant stimulus to the retina.

15. The method of claim 12, wherein the applied stimulus comprises a selectable spatial frequency.

16. The method of claim 12, wherein the applied stimulus comprises a visually perceptible pattern.

17. The method of claim 12, wherein the applied stimulus is applied with at least one LCD.

18. The method of claim 17, wherein the at least one LCD is positioned with respect to the retina along an optical path of a fundus camera.

19. A system for the functional imaging of a retina, comprising:

a. a means for stimulating the retina;

b. a means for interrogating a retinal response to the stimulation means;

c. a means for detecting a reflection of light from the retina resultant from the interrogating means.

20. The system of claim 19, wherein the means for stimulating the retina comprises a means for emitting light.

21. The system of claim 20, wherein the means for emitting light comprises at least one LCD.

22. The system of claim 19, wherein the means for interrogating the retina comprises a means for illuminating the retina via transcleral illumination.

23. The system of claim 19, wherein the means for interrogating the retina comprises a means for emitting light in at least one near infrared wavelength.

24. The system of claim 19, wherein the means for interrogating the retina comprises a means for emitting light in at least one infrared wavelength.

25. The system of claim 19, wherein the means for interrogating the retina comprises an emitter constructed and arranged to emit light at a wavelength in the range of 700 nm to 900 nm.

26. The system of claim 19, wherein the means for interrogating the retina comprises at least one LED

27. The system of claim 19, wherein the means for interrogating the retina comprises a halogen light source.

28. The system of claim 19, wherein the means for interrogating the retina comprises a tungsten light source.

29. The system of claim 19, wherein the means for detecting the reflection comprises a CCD.