Spatially-Resolved Multiply-Excited Autofluorescence and Diffuse Reflectance Spectroscopy: SpectroLive Medical Device for Skin In Vivo Optical Biopsy

This contribution presents the development of an optical spectroscopy device, called SpectroLive, that allows spatially-resolved multiply-excited autofluorescence and diffuse reflectance measurements. Besides describing the device, this study aims at presenting the metrological and safety regulation validations performed towards its aimed application to skin carcinoma in vivo diagnosis. This device is made of six light sources and four spectrometers for detection of the back-scattered intensity spectra collected through an optical probe (made of several optical fibers) featuring four source-to-detector separations (from 400 to 1000 µm). In order to be allowed by the French authorities to be evaluated in clinics, the SpectroLive device was successfully checked for electromagnetic compatibility and electrical and photobiological safety. In order to process spectra, spectral correction and metrological calibration were implemented in the post-processing software. Finally, we characterized the device’s sensitivity to autofluorescence detection: excitation light irradiance at the optical probe tip in contact with skin surface ranges from 2 to 11 W/m², depending on the light source. Such irradiances combined to sensitive detectors allow the device to acquire a full spectroscopic sequence within 6 s which is a short enough duration to be compatible with optical-guided surgery. All these results about sensitivity and safety make the SpectroLive device mature enough to be evaluated through a clinical trial that aims at evaluating its diagnostic accuracy for skin carcinoma diagnosis.

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Determination of the peak absorption wavelength and disaggregation kinetics of TOOKAD in vivo using dynamic, spatially resolved diffuse reflectance spectroscopy in a rabbit model

10.1117/12.465239 ◽

2002 ◽

Cited By ~ 8

Author(s):

Robert A. Weersink ◽

Brian C. Wilson ◽

Michael S. Patterson

Keyword(s):

Diffuse Reflectance ◽

Diffuse Reflectance Spectroscopy ◽

Rabbit Model ◽

Reflectance Spectroscopy ◽

Spatially Resolved ◽

Peak Absorption ◽

Kinetics Of

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Proposal for a Skin Layer-Wise Decomposition Model of Spatially-Resolved Diffuse Reflectance Spectra Based on Maximum Depth Photon Distributions: A Numerical Study

Photonics ◽

10.3390/photonics8100444 ◽

2021 ◽

Vol 8 (10) ◽

pp. 444

Author(s):

Victor Colas ◽

Walter Blondel ◽

Grégoire Khairallah ◽

Christian Daul ◽

Marine Amouroux

Keyword(s):

Diffuse Reflectance ◽

Numerical Study ◽

Skin Layer ◽

Light Transport ◽

Optical Biopsy ◽

Present Contribution ◽

Optical Fiber Probe ◽

Spatially Resolved ◽

Sensor Configuration

In the context of cutaneous carcinoma diagnosis based on in vivo optical biopsy, Diffuse Reflectance (DR) spectra, acquired using a Spatially Resolved (SR) sensor configuration, can be analyzed to distinguish healthy from pathological tissues. The present contribution aims at studying the depth distribution of SR-DR-detected photons in skin from the perspective of analyzing how these photons contribute to acquired spectra carrying local physiological and morphological information. Simulations based on modified Cuda Monte Carlo Modeling of Light transport were performed on a five-layer human skin optical model with epidermal thickness, phototype and dermal blood content as variable parameters using (i) wavelength-resolved scattering and absorption properties and (ii) the geometrical configuration of a multi-optical fiber probe implemented on an SR-DR spectroscopic device currently used in clinics. Through histograms of the maximum probed depth and their exploitation, we provide numerical evidence linking the characteristic penetration depth of the detected photons to their wavelengths and four source–sensor distances, which made it possible to propose a decomposition of the DR signals related to skin layer contributions.

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Protocol for optical percutaneous needle biopsy of the liver

10.21203/rs.3.pex-1126/v1 ◽

2020 ◽

Author(s):

Viktor Dremin ◽

Elena Potapova ◽

Evgeny Zherebtsov ◽

Ksenia Kandurova ◽

Valery Shupletsov ◽

...

Keyword(s):

Needle Biopsy ◽

Diffuse Reflectance ◽

Histological Analysis ◽

Diffuse Reflectance Spectroscopy ◽

Optical Measurements ◽

Optical Biopsy ◽

Percutaneous Needle Biopsy ◽

New Methods ◽

Cancer Types

Abstract Liver cancer remains one of the most widespread cancer types worldwide. The time spent on the diagnosis is one of crucial factors ensuring the effectiveness of treatment. As percutaneous needle biopsy remains the gold standard for liver diagnosis, it is necessary to develop new methods for improving this procedure. One of the most promising directions is multimodal optical biopsy. The proposed protocol describes the methodology of real-time in vivo optical measurements of liver lesions during the percutaneous needle biopsy of the liver. The multimodal approach combines the methods of fluorescence and diffuse reflectance spectroscopy and conventional histological analysis.

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