Design and characterization of a novel multimodal fiber-optic probe and spectroscopy system for skin cancer applications

Abstract

The design and characterization of an instrument combining Raman, fluorescence, and reflectance spectroscopic modalities is presented. Instrument development has targeted skin cancer applications as a novel fiber-optic probe has been specially designed to interrogate cutaneous lesions. The instrument is modular and both its software and hardware components are described in depth. Characterization of the fiber-optic probe is also presented, which details the probe's ability to measure diagnostically important parameters such as intrinsic fluorescence and absorption and reduced scattering coefficients along with critical performance metrics such as high Raman signal-to-noise ratios at clinically practical exposure times. Validation results using liquid phantoms show that the probe and system can extract absorption and scattering coefficients with less than 10% error. As the goal is to use the instrument for the clinical early detection of skin cancer, preliminary clinical data are also presented, which indicates our system's ability to measure physiological quantities such as relative collagen and nicotinamide adenine dinucleotide concentration, oxygen saturation, blood volume fraction, and mean vessel diameter.

Label‐Free Molecular Imaging of Biological Cells and Tissues by Linear and Nonlinear Raman Spectroscopic Approaches

“…[311] Them ultimodal approach was evaluated for real time in vivo diagnosis of cancer in the esophagus during clinical endoscopic examinations.Asimilar system combining reflectance,f luorescence,a nd Raman spectroscopy detected features of vulnerable atherosclerotic plaques from twelve patients under ex vivo conditions. [313] Preliminary clinical data indicated the ability of the system to measure physiological quantities,s uch as the relative collagen and nicotinamide adenine dinucleotide concentrations,t he oxygen saturation, the blood volume fraction, and the mean vessel diameter. Another group designed an instrument combining Raman, fluorescence,and reflectance spectroscopic modalities for skin cancer applications.…”

Combined fiber probe for fluorescence lifetime and Raman spectroscopy

“…The fast imaging methodology can provide an overview image to identify suspicious tissue areas (“red flags”) that subsequently can be analyzed in detail by Raman spectroscopy. Several research groups have been working on the development of such multimodal “red flag” endoscopic Raman probes, such as OCT combined with Raman [9], intrinsic fluorescence and/or diffuse reflectance spectroscopy and Raman [12, 13]. …”

Raman active components of skin cancer

“…Data were collected from an optical fiber probe [27] integrated in a multimodal spectroscopy system [28] on different sites, such as scalp, nose, earlobe, shoulder and thigh. Lesion types including basal cell carcinoma (BCC, 19 lesions), squamous cell carcinoma (SCC, 38 lesions), actinic keratosis (AK, 14 lesions), benign pigmented lesion (PL, 17 lesions) and malignant melanoma (MM, 12 lesions).…”