New optical sensing technique of tissue viability and blood flow based on nanophotonic iterative multi-plane reflectance measurements

Abstract

Physiological substances pose a challenge for researchers since their optical properties change constantly according to their physiological state. Examination of those substances noninvasively can be achieved by different optical methods with high sensitivity. Our research suggests the application of a novel noninvasive nanophotonics technique, ie, iterative multi-plane optical property extraction (IMOPE) based on reflectance measurements, for tissue viability examination and gold nanorods (GNRs) and blood flow detection. The IMOPE model combines an experimental setup designed for recording light intensity images with the multi-plane iterative Gerchberg-Saxton algorithm for reconstructing the reemitted light phase and calculating its standard deviation (STD). Changes in tissue composition affect its optical properties which results in changes in the light phase that can be measured by its STD. We have demonstrated this new concept of correlating the light phase STD and the optical properties of a substance, using transmission measurements only. This paper presents, for the first time, reflectance based IMOPE tissue viability examination, producing a decrease in the computed STD for older tissues, as well as investigating their organic material absorption capability. Finally, differentiation of the femoral vein from adjacent tissues using GNRs and the detection of their presence within blood circulation and tissues are also presented with high sensitivity (better than computed tomography) to low quantities of GNRs (<3 mg).

Depth Scattering Characterization of Multi-Layer Turbid Media Based on Iterative Multi-Plane Reflectance Measurements

“…4b). The opposite behavior between those two regimes was observed as was expected and reported in our previous studies [21][22][23][24].…”

“…The reconstructed phase image shows two distinguishable areas, separated by a circular border, which was reported in our previous papers [21][22][23][24]. The cyan circle, in the center of the phase image, represents the area closer to the radiation source, which is the single scattering regime.…”

“…We have presented previously the iterative multi-plane optical property extraction (IMOPE) technique [19][20][21][22][23][24][25]. The IMOPE technique is a noninvasive nanophotonics technique for extracting the scattering properties of a medium based on a single light source.…”

“…Citation information: DOI 10.1109/JPHOT.2020.3017697, IEEE Photonics Journal 2 based on the steady-state diffusion reflection theory [29][30][31] with the master-slave dual-source configuration [32]. The reflection-based IMOPE was applied for tissues viability test and detection of gold nanorods and blood flow in the femoral vein of a mouse [21], and also the detection of different tissue types of a mouse [23]. Mostly, the IMOPE was applied for biomedical purposes hence the red wavelength was used.…”

Self-Calibration Phenomenon for Near-Infrared Clinical Measurements: Theory, Simulation, and Experiments

“…However, we have found supporting reports on reflection from a semi-infinite medium in diffusion reflection (DR) 10 , 11 and reflection phase measurements. 12 Mourant 10 reported on a source–detector separation that does not depend on scattering properties at the range close to the light source. Mourant presented a Monte Carlo (MC) simulation and phantom experiments of reflected light from a semi-infinite medium.…”