Method for ocular surface imaging

1. A method of detecting an ocular surface disease, the method comprising:

illuminating the cornea of an ocular surface of an eye of a patient with a light from a light source, wherein the light is transmitted in a first predetermined wavelength range by an illumination filter positioned between the light source and the ocular surface, and wherein the light in the first predetermined wavelength range excites a contrast agent bound to defects on the ocular surface;

capturing, with a camera, a light signal emitted from the contrast agent to generate a full-field, in focus image of the cornea having a depth of field sufficient to capture a full depth of the cornea, wherein the light signal is transmitted in a second predetermined wavelength range by an imaging filter to the camera, wherein the imaging filter comprises a Fourier bandpass filter removing low frequency components and enhancing detection of the contrast agent;

wherein the camera transmits signals representing the full-field, in focus image of the cornea for image analysis by a processor in communication with a machine readable storage medium comprising instructions that, when executed by the processor, provide quantitative analysis of contrast agent intensity and distribution, and wherein the ocular surface disease is uveitis, conjunctivitis, keratitis, keratoconjunctivitis, vernal keratoconjunctivitis (VKC), atopic keratoconjunctivitis (AKC), autoimmune disorders of the ocular surface, meibomianitis, conjunctival hyperemia, eyelid hyperemia, ocular rosacea, ocular inflammation, or eye lid swelling; and

segmenting stained objects within the full-field, in focus image to create a segmented image using a segmentation threshold.

2. The method of claim 1 , wherein the optical density of the illumination tilter at wavelengths other than the first predetermined wavelength range is at least 5.0 and the optical density of the imaging filter is at least 5.0 at wavelengths other than the second predetermined wavelength range.

3. The method of claim 1 , wherein the contrast agent is fluorescein, the illumination filter transmits light having a wavelength in a range of 465 to 500 nm, and the imaging filter filters light to block all light that does not have a wavelength greater than 515 nm to avoid overlapping wavelengths.

4. A method of detecting an ocular surface disease, the method comprising:

illuminating the cornea of an ocular surface of an eye of a patient with a light from a light source, wherein the light is polarized in a first orientation by an illumination filter positioned between the light source and the ocular surface, and wherein the light polarized in the first orientation excites a contrast agent bound to defects on the ocular surface;

capturing, with a camera, a light signal emitted from the contrast agent to generate a full-field, in focus image of the cornea having a depth of field sufficient to capture a full depth of the cornea, wherein the light signal is polarized in a second orientation by an imaging filter, and is transmitted by the imaging filter to the camera, and wherein a Fourier bandpass filter is applied to the full-field, in focus image removing low frequency components and enhancing detection of the contrast agent;

wherein the camera transmits signals representing the full-field, in focus image of the cornea for image analysis by a processor in communication with a machine readable storage medium comprising instructions that, when executed by the processor, provide quantitative analysis of contrast agent intensity and distribution, and wherein the ocular surface disease is uveitis, conjunctivitis, keratitis, keratoconjunctivitis, vernal keratoconjunctivitis (VKC), atopic keratoconjunctivitis (AKC), autoimmune disorders of the ocular surface, meibomianitis, conjunctival hyperemia, eyelid hyperemia, ocular rosacea, ocular inflammation, or eye lid swelling;

segmenting stained objects within the full-field, in focus image to create a segmented image using a segmentation threshold; and

iteratively adjusting the segmentation threshold until a rate of change in a number of pixels in the segmented full-field, in focus image has reached a predetermined level.

5. The method of claim 4 , wherein the illumination filter and the imaging filter are polar filters, and are adjusted in opposite directions.

6. The method of claim 4 , wherein the illumination filter and the imaging filter are circular polar filters, and wherein one of the filters is left circular and the other is right circular.

7. The method of claim 1 , wherein the illumination filter and the imaging filter are polar filters, and are adjusted in opposite directions.

8. The method of claim 4 , wherein the illumination filter transmits light having a wavelength in a range of 465 to 500 nm, and the imaging filter filters light to block all light that does not have a wavelength greater than 515 nm to avoid overlapping wavelengths.

9. The method of claim 1 , further comprising:

capturing a plurality of images of the cornea with the camera, each of the plurality of images being captured at a different focal plane; and

rendering the plurality of images into the full-field, in focus image of the cornea.

10. The method of claim 1 , further comprising iteratively adjusting the segmentation threshold until a rate of change in a number of pixels in the segmented full-field, in focus image has reached a predetermined level.

11. A method of detecting an ocular surface disease, the method comprising:

illuminating the cornea of an ocular surface of an eye of a patient with a light from a light source, wherein the light is transmitted in a first wavelength range by an illumination filter positioned between the light source and the ocular surface, and wherein the light in the first wavelength range excites a contrast agent bound to defects on the ocular surface;

capturing, with a camera, a light signal emitted from the contrast agent to generate a full-field, in focus image of the cornea having a depth of field sufficient to capture a full depth of the cornea, wherein the light signal is transmitted in a second wavelength range by an imaging filter to the camera, wherein the imaging filter is positioned between the ocular surface and the camera;

wherein the camera transmits signals representing the full-field, in focus image of a cornea for image analysis by a processor in communication with a machine readable storage medium comprising instructions that, when executed by the processor, provide quantitative analysis of contrast agent intensity and distribution and wherein the illumination filter and the imaging filter are polar filters that are adjusted in opposite directions; and

segmenting stained objects from the full-field, in focus image to create a segmented image using an adaptive segmentation threshold.

12. The method of claim 11 , wherein the illumination filter transmits light having a wavelength in a range of 465 to 500 nm, and the imaging filter filters light to block all light that does not have a wavelength greater than 515 nm to avoid overlapping wavelengths.

13. The method of claim 11 , comprising transmitting signals from the camera to a machine readable storage medium, the signals comprising instructions that provide quantitative analysis of contrast agent intensity and distribution for detecting the ocular surface disease of at least one of conjunctivitis, keratitis, keratoconjunctivitis, vernal keratoconjunctivitis (VKC), or atopic keratoconjunctivitis (AKC).

14. The method of claim 11 , wherein the depth of focus is about 2.8 millimeters.