Enhancement of OCT imaging by blood optical clearing in vessels – A feasibility study

AbstractThe results of a feasibility study of the application of PEG-300 and fructose as two independent optical clearing agents for the reduction of light scattering in biological tissues are presented.An OCT system operating at 1300 nm was used to study optical clearing effects. InThe intradermal injection of fructose in combination with the intravenous injection of PEG-300 led to a rapid optical clearing effect. In the experiments on miceThe experiments on mice have clearly demonstrated that intradermal and intravenous injections of optical clearing agents enhanced light transport through the skin and blood vessels.

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Increased Light Transport in Skin Using Mechanical Compression

ASME 2009 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2009-206628 ◽

2009 ◽

Author(s):

Chris W. Drew ◽

Alondra Izquierdo-Roman ◽

Yajing Liu ◽

Christopher G. Rylander

Keyword(s):

Light Scattering ◽

Structural Modification ◽

Near Infrared ◽

Morphological Structure ◽

Light Transport ◽

Optical Clearing ◽

Treatment Techniques ◽

Infrared Wavelengths ◽

Tissue Optical Clearing ◽

Highly Scattering Medium

The complex morphological structure of skin with its variations in the indices of refraction of components therein provides a highly scattering medium for visible and near-infrared wavelengths of light. “Tissue optical clearing” increases transmission of near-collimated light in biological tissue, potentially enabling improved optical analysis and treatment techniques. Numerous methods of tissue optical clearing have been hypothesized using hyperosmostic agents [1]. These methods propose reduction in light scattering by means of dehydration of tissue constituents, replacement of interstitial or intracellular water with higher refractive agents, or structural modification or dissociation of collagen fibers [2]. It has been suggested that dehydration of tissue constituents alone can reduce light scattering by expulsing water between collagen fibrils, increasing protein and sugar concentrations, and decreasing refractive index mismatch [3].

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Coupled Poroviscoelastic and Optical Monte Carlo Simulation of Dynamic Light Transport Through Indented Soft Tissue

Volume 1B: Extremity; Fluid Mechanics; Gait; Growth, Remodeling, and Repair; Heart Valves; Injury Biomechanics; Mechanotransduction and Sub-Cellular Biophysics; MultiScale Biotransport; Muscle, Tendon and Ligament; Musculoskeletal Devices; Multiscale Mechanics; Thermal Medicine; Ocular Biomechanics; Pediatric Hemodynamics; Pericellular Phenomena; Tissue Mechanics; Biotransport Design and Devices; Spine; Stent Device Hemodynamics; Vascular Solid Mechanics; Student Paper and Design Competitions ◽

10.1115/sbc2013-14683 ◽

2013 ◽

Author(s):

William C. Vogt ◽

Christopher G. Rylander

Keyword(s):

Refractive Index ◽

Water Distribution ◽

Biological Tissues ◽

Light Transport ◽

Mathematical Framework ◽

Interstitial Fluid Flow ◽

Tissue Water ◽

Porous Flow ◽

Optical Clearing ◽

Tissue Optical Properties

Biological tissues are heterogeneous materials that may be considered mixtures of water, proteins, and cells. The large mismatch in refractive index between these constituents causes tissues to be highly turbid, diffusing light and limiting the efficacy of optical diagnostic and therapeutic techniques [1]. Mechanical optical clearing is a technique for reducing tissue scattering and absorption using controlled tissue deformation. Mechanical optical clearing is performed using indentation to locally modify tissue optical properties, including refractive index [2] and reduced scattering coefficient [3]. This effect is attributed to transient changes in tissue water distribution as a result of interstitial fluid flow due to tissue compression. In this study, we have developed a multi-domain mathematical framework for simulating mechanical optical clearing effects on tissue mechanical and optical behavior, including hyperelasticity, viscoelasticity, porous flow, and light transport. This model was then fitted to mechanical force data and used to predict experimentally measured optical transmission.

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Optical Clearing of Biological Tissues: Prospects of Application for Multimodal Malignancy Diagnostics

Multimodal Optical Diagnostics of Cancer ◽

10.1007/978-3-030-44594-2_2 ◽

2020 ◽

pp. 107-131

Author(s):

Elina A. Genina ◽

Luís M. C. Oliveira ◽

Alexey N. Bashkatov ◽

Valery V. Tuchin

Keyword(s):

Biological Tissues ◽

Optical Clearing ◽

Prospects Of Application

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Molecular modeling of post-diffusion stage of biotissue optical clearing under effect of iohexol aqueous solution

Journal of Physics Conference Series ◽

10.1088/1742-6596/2103/1/012048 ◽

2021 ◽

Vol 2103 (1) ◽

pp. 012048

Author(s):

I T Shagautdinova ◽

A M Likhter ◽

K V Berezin ◽

K N Dvoretsky ◽

V V Nechaev ◽

...

Keyword(s):

Experimental Data ◽

Molecular Dynamics ◽

Aqueous Solution ◽

Molecular Modeling ◽

Biological Tissues ◽

Optical Clearing ◽

X Ray ◽

Diffusion Stage ◽

Collagen Peptide ◽

Main Components

Abstract Interaction of iohexol (Omnipaque), an X-Ray contrast agent, with a mimetic peptide of collagen (GPH)3 as one of the main components of biological tissues has been studied with the use of methods of classical molecular dynamics (GROMACS). Complex molecular modeling of the post-diffusion stage of optical clearing allowed to evaluate such parameters as the average number of hydrogen bonds, formed between the clearing agent and collagen per unit time, and the immersion agent’s effect on changes in the collagen peptide volume. The obtained results are compared with similar results for glycerol, a polyatomic alcohol, and with the existing experimental data on the efficiency of optical clearing of these immersion agents.

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