Violet LED lamp-induced autofluorescence spectroscopy for non-melanoma skin cancer detection

ETCHEVERRY, MARIA EUGENIA; ÁNGEL, PASQUALE MIGUEL; GARAVAGLIA MARIO

Bariloche

Congreso; RAFA2022; 2022

Skincancers are a serious disease, its incidence growing overworld as aresult of the increase in the dose of nonhealthy UV radiation,climatic changes and the social conditions of individuals. The earlydetection of and the development of more efficient treatments forthis neoplastic disease are crucial for improving the survival rate.A variety of new and emerging diagnostic strategies based onspectroscopic techniques such as non-invasiveone-point fluorescence (PF) detection,are available to improve the screening procedure [1,2]. PFtechnique provides useful information for monitoring the evolution ofthe abundance and distribution of endogenous or endogenousfluorophores associated with the neoplastic disease in low-pigmentedsuperficial neoplasia [3,4].Themain objective of the present study was to develop a violet LED lightsource suitable for medical application devoted to the diagnostic andtreatment of non-melanoma skin cancers. For this propose, weconstructed a 12 W violet LED lamp (withmaximum emission peak at 405 nm)made up of four mobile 3 W LED, each one coupled to a heatsink and alens, and mounted on a platform with adjustable screws. The powersupply allows to modify the intensity of illumination. The LED lampwas characterized employing a spectrometer provided with a CCDdetector, UV coating filter for reduction of second-order effect,couple to an optical fiber. The irradiance for different distancesbetween the lamp and the detector was assessed. Furthermore, theradiant power and the radiant intensity were evaluated. Data werecompared with a simulated LED lamp by using the Zemax optic softwarefor the realization of luminaires with the desired characteristicsand modes of operation to deliver the energy density at the interestpoint, as required for medical applications.Thedeveloped lamp in combination with a portable spectrometer wasemployed under medical supervision to detect differences in theemission spectrum of skin suspicious regions and healthy ones locatedat the head of a patient with non-melanoma skin cancer. The light ofthe LED lamp was concentrated in the examined region by means of theproper focusing of the four individual LEDs, rendering a highintensity homogeneous spot. Thus, endogenous chromophores at the skinwere exited, and the emission intensity appeared to be enough todetect an enhanced peaked structure around 600 nm for some suspiciousregions before treatment in comparison with healthy regions. Thesedifferences can be related to the augmented protoporphyrin IX contentin neoplastic regions. Results presented inthis work indicates the usefulness of the developed and characterizedLED lamp as an easy-to-use device for the non-invasive detection ofskin neoplastic pathologies, before and after treatment, with the aimof better define the malignant regions as well as predict the outcomeof a certain treatment. p { margin-bottom: 0.25cm; line-height: 120% }