US 12,263,005 B2
Dual-slope method for enhanced depth sensitivity in diffuse optical spectroscopy
Sergio Fantini, Winchester, MA (US); Angelo Sassaroli, Arlington, MA (US); and Giles Blaney, Somerville, MA (US)
Assigned to Trustees of Tufts College, Medford, MA (US)
Appl. No. 17/617,654
Filed by Trustees of Tufts College, Medford, MA (US)
PCT Filed Jun. 12, 2020, PCT No. PCT/US2020/037466
§ 371(c)(1), (2) Date Dec. 9, 2021,
PCT Pub. No. WO2020/252286, PCT Pub. Date Dec. 17, 2020.
Claims priority of provisional application 62/861,650, filed on Jun. 14, 2019.
Prior Publication US 2022/0218267 A1, Jul. 14, 2022
Int. Cl. A61B 5/00 (2006.01); A61B 5/026 (2006.01); A61N 5/06 (2006.01); H01J 49/40 (2006.01)
CPC A61B 5/4064 (2013.01) [A61B 5/0075 (2013.01); A61B 5/0261 (2013.01); A61N 5/0622 (2013.01); H01J 49/40 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An apparatus comprising
a processor and
a spectrometer, said spectrometer comprising a first source, a second source, a first detector, and a second detector,
wherein said processor is configured to receive first and second data indicative of signals detected by said detectors in response to illumination by said first and
second sources, respectively,
wherein said first and second sources emit near-infrared radiation,
wherein “S1D1” is a distance between said first source and said first detector,
wherein “S1D2” is a distance between said first source and said second detector,
wherein “S2D1” is a distance between said second source and said first detector,
wherein “S2D2” is a distance between said second source and said second detector,
wherein “R1”=|S1D1−S1D2|,
wherein “R2”=|S2D1−S2D2|, wherein R1=R2,
wherein one of the following conditions is met:
(1) S1D1<S1D2 and S2D1>S2D2 and
(2) S1D1>S1D2 and S2D1<S2D2,
wherein said processor is configured to derive, from each of said first and second data, a first parameter indicative of a first slope and a second parameter indicative of a second slope,
wherein said first and second parameters represent a spatial rate-of-change,
wherein an average of said first and second slopes results in a cancellation of temporal fluctuation of said spatial rate of change,
wherein said spatial rate-of-change is selected from the group consisting of: a spatial rate-of-change of an average intensity of said near-infrared radiation, a spatial rate-of-change of a phase of said near-infrared radiation, and a spatial rate-of-change of a mean time-of-flight data for said near-infrared radiation, and
wherein said processor is further configured to provide output data based on the average of said first and second slopes, thereby promoting reduced sensitivity to superficial layers and increased sensitivity to deeper portions of a medium that is under investigation.