Through focus retinal image capturing

Patent metadata

Field	Value
Publication number	US-10799115-B2
Application number	US-201715651853-A
Country	US
Kind code	B2
Filing date	Jul 17, 2017
Priority date	Feb 27, 2015
Publication date	Oct 13, 2020
Grant date	Oct 13, 2020

Abstract

An apparatus for producing a non-mydriatic fundus image is disclosed. The apparatus can include a processor and memory, as well as an illumination component and a camera with a variable focus lens. The apparatus can be configured to adjust the focus of the lens to a plurality of different diopter ranges and capture at least one image at each of the plurality of different diopter ranges. Using the captured images, three-dimensional maps of the fundus may be generated. Three-dimensional maps of the fundus may be used to screen or diagnose various diseases.

First claim

What is claimed is:

1. A non-mydriatic fundus imaging apparatus, the apparatus comprising:
a processor and memory; and
a camera including a lens, the camera operatively coupled to the processor,
wherein the memory stores instructions that, when executed by the processor, cause the apparatus to:
adjust a focus of the lens to a plurality of different diopter ranges;
capture a plurality of images of a fundus, wherein the camera captures at least one image at each of the plurality of different diopter ranges; and
after capturing each of the plurality of images of the fundus, generate a three-dimensional map of the fundus using each of the plurality of images of the fundus, including:
identify a first region, each of the plurality of images having corresponding first regions;
evaluate each of the respective first regions of each of the plurality of images for focus quality, thereby generating a focus quality score for each of the respective first regions of each of the plurality of images;
generate a slope of the fundus based on a change in the focus quality score in the first regions across the plurality of images of the fundus; and
use the slope to generate the three-dimensional map of the fundus.

2. The apparatus according to claim 1 , the instructions further causing the apparatus to:
identify one or more areas of interest on the three-dimensional map of the fundus; and

screen the one or more areas of interest for indications of disease.

3. The apparatus according to claim 1 , the instructions further causing the apparatus to:
identify one or more areas of interest on the three-dimensional map of the fundus; and

identify a diagnosis based on the one or more areas of interest.

4. The apparatus of claim 3 , the diagnosis including a determination of whether the three dimensional map is indicative of papilledema.

5. The apparatus according to claim 4 , the diagnosis further including a determination of a stage of papilledema.

6. The apparatus according to claim 3 , further comprising a display coupled to the memory and to the processor and configured to display an image or text representative of the diagnosis.

7. The apparatus according to claim 1 , the instructions further causing the apparatus to:
adjust the focus of the lens and capture subsequent images until images have been captured of a depth of field from −6 diopters to +6 diopters.

8. The apparatus according to claim 6 , wherein each adjustment of the focus is by +/−3 diopters.

9. The apparatus according to claim 1 , wherein the images are captured sequentially in less than about 150 milliseconds.

10. The apparatus according to claim 1 , further comprising a visible light component configured to illuminate during the capture of the plurality of images.

11. A method for screening for optic nerve edema with a non-mydriatic fundus imaging apparatus, the method comprising:
adjusting a lens of a camera to focus on each of a plurality of different diopter ranges in a depth of field;
capturing at least one image at each of the plurality of different diopter ranges;
generating a three-dimensional map of a fundus using the at least one image captured at each of the plurality of different diopter ranges, including:
identifying a first region, each of the images having corresponding first regions;
evaluating each of the respective first regions of each of the images for focus quality, thereby generating a focus quality score for each of the respective first regions of each of the plurality of images;
generating a slope of the fundus based on a change in the focus quality score in the first regions across the plurality of images of the fundus; and
using the slope to generate the three-dimensional map of the fundus; and

based on the three-dimensional map, screening for optic nerve edema.

12. The method according to claim 11 , further comprising identifying one or more areas of interest on the three-dimensional map of the fundus, wherein the screening for optic nerve edema includes analyzing the one or more areas of interest.

13. The method according to claim 12 , wherein screening for optic nerve edema includes identifying a diagnosis.

14. The method according to claim 13 , further comprising displaying an indication of the diagnosis on a display.

15. The method according to claim 12 , wherein the depth of field is from −6 diopters to 6 diopters.

16. A non-mydriatic fundus image capture system, comprising:
a housing;
an image capture device coupled to the housing, the image capture device including a visible light component configured to illuminate;
a display;
a processing unit; and
memory storing instructions that, when executed by the processing unit, cause the system to:
capture a plurality of images of a fundus in an image capture mode,
wherein the image capture mode includes a plurality of adjustments of a lens of the image capture device such that the image capture device captures an image at each of the plurality of adjustments in a depth of field focus range, wherein the light from the visible light component is gathered in a single step for each image;
after capturing each of the plurality of images of the fundus, generate a three-dimensional map of the fundus using each of the plurality of images of the fundus, including:
identify a first region, each of the plurality of images having corresponding first regions;
evaluate each of the respective first regions of each of the plurality of images for focus quality, thereby generating a focus quality score for each of the respective first regions of each of the plurality of images;
generate a slope of the fundus based on a change in the focus quality score in the first regions across the plurality of images of the fundus; and
use the slope to generate the three-dimensional map of the fundus;

identify one or more areas of interest on the three-dimensional map of the fundus; and
screen the one or more areas of interest for indications of disease.

17. The non-mydriatic fundus image capture system according to claim 16 , the instructions further causing the apparatus to:
identify a diagnosis based on the one or more areas of interest; and
display a diagnosis image representing the diagnosis.

18. The non-mydriatic fundus image capture system according to claim 17 , the instructions further causing the apparatus to adjust the focus of the lens and capture subsequent images until images have been captured of a depth of field from −6 diopters to +6 diopters, wherein each adjustment of the focus is by +/−3 diopters.

19. The apparatus according to claim 1 , wherein the first region is a 5 pixel by 5 pixel region.

20. The apparatus according to claim 19 , wherein slopes are generated for regions neighboring the first region.

Assignees

• Welch Allyn Inc

Inventors

• Wang Ynjiun Paul

Classifications

• A61B3/152

  for aligning · CPC title

• G06T2207/30041

  Eye; Retina; Ophthalmic · CPC title

• A61B3/113

  for determining or recording eye movement · CPC title

• G06T2207/20212

  Image combination · CPC title

• A61B3/0091

  Fixation targets for viewing direction · CPC title