US 11,771,323 B2
Optical time-of-flight imaging methods and systems for surgical guidance and fluorescence depth estimation in tissue
Petr Bruza, Lebanon, NH (US); and Brian Pogue, Hanover, NH (US)
Assigned to THE TRUSTEES OF DARTMOUTH COLLEGE
Appl. No. 17/794,297
Filed by THE TRUSTEES OF DARTMOUTH COLLEGE, Hanover, NH (US)
PCT Filed Nov. 15, 2021, PCT No. PCT/US2021/059420
§ 371(c)(1), (2) Date Jul. 21, 2022,
PCT Pub. No. WO2022/104228, PCT Pub. Date May 19, 2022.
Claims priority of provisional application 63/114,049, filed on Nov. 16, 2020.
Claims priority of provisional application 63/113,914, filed on Nov. 15, 2020.
Prior Publication US 2023/0047584 A1, Feb. 16, 2023
Int. Cl. G01N 21/64 (2006.01); A61B 5/00 (2006.01)
CPC A61B 5/0071 (2013.01) [G01N 21/6408 (2013.01); G01N 21/6458 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A system for depth resolved imaging of fluorophore concentrations in tissue comprising:
a pulsed light source operable at a stimulus wavelength of the fluorophore concentrations and configured to illuminate the tissue, the pulsed light source configured to provide light pulses of less than one nanosecond in width;
at least one time gated electronic camera configured to generate reflectance images and fluorescent emissions images of the tissue, the time gated electronic camera configurable to image in time windows synchronized to pulses of the pulsed light source with time gate delay resolution of less than 100 picoseconds;
a filter device in a light path of the pulsed light source that is configurable as a first filter having a passband for fluorescent emissions of the fluorophore concentrations while blocking light of the stimulus wavelength of the fluorophore concentrations, and as a second filter having a passband for light of the stimulus wavelength of the fluorophore concentrations; and
an image processor coupled to receive reflectance images and fluorescent emissions images from the time gated electronic camera, the image processor having a memory with firmware, the image processor configured to produce images incorporating depth information determined by time of flight of the light of the stimulus wavelength and the fluorescent emissions.