Optical overlay device
Devices and methods for visibly highlighting areas of a region including an imager configured to image the region with a sensitivity to at least one of wavelength, light level, or contrast greater than the human eye, an overlay element configured to visibly highlight areas of the region and registered to the imager to produce alignment of imaged features with highlighted features at the same location on the region, and at least one of a controller executing a program or logic configured to process acquired images from the imager to identify areas of the region determined not visible to the human eye, and control the overlay element to visibly highlight those areas on the region.
1. A device for intra-operatively identifying a parathyroid tissue of a living subject, comprising:
a light source configured to emit a beam of light having a wavelength of substantially 785 nm for illuminating tissues in the neck area of the living subject to stimulate autoflourescence from parathyroid tissue in the neck region;
an imager for collecting light emitted from the illuminated tissues in a wavelength range of 800 to 1000 nm in response to the illumination, corresponding to the autoflourescence emitted from parathyroid tissue;
an overlay element configured to visibly highlight areas of the region and registered to the imager to produce alignment of the autoflourescent emitting tissues with highlighted features at the same location on the region, and;
a processor configured to process acquired images from the imager to identify the autoflourescent tissue regions, and control the overlay element to visibly highlight the regions in the neck area.
2. The system of claim 1 wherein the illumination is modulated and the imager is configured to capture images synchronized to the modulation, allowing for immunity to ambient light.
3. The system of claim 1 wherein the imager, illuminator, and overlay element are configured as one unit at one working distance.
4. The system of claim 1 wherein the highlighting is configured to be at least one of a single visible color or multiple colors, selected for high contrast with the colors of the region of interest.
5. The system of claim 1 wherein the processing includes thresholding the image to highlight the region of interest where the thresholding includes at least one of a predetermined intensity level, predetermined intensity variance, or ratio of intensities at 2 or more locations, 2 or more wavelengths, or at 2 or more locations of full width half maximum signal.
6. The system of claim 1 wherein the overlay element comprises one or more of a standard light source projector, a laser scanner controlled by the processor to project the visible image by scanning the image on the region, or one or more visible LED's actuated by the controller to scan the image on the region.
7. A method for intra-operatively identifying a parathyroid tissue of a living subject, comprising:
illuminating with a beam of light, from an illuminator at a wavelength of substantially 785 nm, tissues in the neck area of the living subject to stimulate autoflourescence from parathyroid tissue in the neck region;
imaging light emitted from the illuminated tissues in a wavelength range of 800 to 1000 nm in response to the illumination, corresponding to the autoflourescence emitted from parathyroid tissue;
registering an overlay element with an imager to produce alignment of the autoflourescent emitting tissues with highlighted features at the same location on the region, and;
processing acquired images from the imager to identify the autoflourescent tissue regions, and controlling the overlay element to visibly highlight the regions in the neck area.
8. The method of claim 7 wherein the illumination is modulated and the imager is configured to capture images synchronized to the modulation, allowing for immunity to ambient light.
9. The method of claim 7 wherein the imager, illuminator, and overlay element are configured as one unit at one working distance.
10. The method of claim 7 wherein the highlighting is configured to be at least one of a single visible color or multiple colors, selected for high contrast with the colors of the region of interest.
11. The method of claim 7 wherein the processing includes thresholding the image to highlight the region of interest where the thresholding includes at least one of a predetermined intensity level, predetermined intensity variance, or ratio of intensities at 2 or more locations, 2 or more wavelengths, or at 2 or more locations of full width half max signal.
12. The method of claim 7 wherein the highlighting is done by one or more of a standard light source projector, a laser scanner controlled by the controller to project the visible image by scanning the image on the region, or one or more visible LED's actuated by the controller to scan the image on the region.