Infrared imaging spectroscopy of skin cancer lesions

Skin cancer is a disease of the twenty-first century since, unfortunately, being tan is associated to be healthy and good looking. UV radiation produces one of the most aggressive kinds of skin cancer: melanoma; once the damage is done there is no other solution that a rapid and effective diagnosis. Clinical examination and biopsies have shown to be slow and costly in many ways, so the possibility of getting a non-invasive optical detection of skin melanomas became a hot topic in biophotonics. In this context, multispectral imaging systems have approached the problem, but none of them worked inside the infrared range. Hence, this work has been proposed as an interesting, long-term project to further investigate about the possibilities of infrared imaging spectroscopy for the early detection of skin cancer through the development of such a system based on an InGaAs camera

Evaluation of new optical spectroscopic techniques for tissue studies

Imaging techniques have developed very fast and extensively in the past few years, becoming essential for the study of structures, properties and processes in all the fields in science. Non-invasive tissular studies have become especially popular nowadays because they permit to study processes in vivo, without the alteration of the sample under focus, which were not possible to be studied with the imaging techniques in the past. Fluorescence spectroscopy is one of the imaging techniques that has been developed towards the non-invasive studies of polymers, inorganic materials, cells and tissues; with the purpose of characterize them. The main objectives of this work have been proposed in order to further investigate about the possibilities of fluorescence spectroscopy and consisted on the evaluation of two different applications. Although the tittle of the offer is maintained, the focus of the work has changed to the evaluation of the problems that are introduced right after this lines. Both are proposed to be studied at the same time since it is possible to carry out both of them under the same system and with similar methodologies.Ingeniería Biomédic

Morphological study of skin cancer lesions through a 3D scanner based on fringe projection and machine learning

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Spectroscopic evaluation of red blood cells of thalassemia patients with confocal microscopy: a pilot study

Hemoglobinopathies represent the most common single-gene defects in the world and pose a major public health problem, particularly in tropical countries, where they occur with high frequency. Diagnosing hemoglobinopathies can sometimes be difficult due to the coexistence of different causes of anemia, such as thalassemia and iron deficiency, and blood transfusions, among other factors, and requires expensive and complex molecular tests. This work explores the possibility of using spectral confocal microscopy as a diagnostic tool for thalassemia in pediatric patients, a disease caused by mutations in the globin genes that result in changes of the globin chains that form hemoglobin—in pediatric patients. Red blood cells (RBCs) from patients with different syndromes of alpha-thalassemia and iron deficiency (including anemia) as well as healthy (control) subjects were analyzed under a Leica TCS SP8 confocal microscope following different image acquisition protocols. We found that diseased RBCs exhibited autofluorescence when excited at 405 nm and their emission was collected in the spectral range from 425 nm to 790 nm. Three experimental descriptors calculated from the mean emission intensities at 502 nm, 579 nm, 628 nm, and 649 nm allowed us to discriminate between diseased and healthy cells. According to the results obtained, spectral confocal microscopy could serve as a tool in the diagnosis of thalassemia.This research was funded by Spanish Ministry of Economy and Competitiveness, grant number DPI2017-89414-R. L.R.-B. thanks the Ministry of Science, Innovation and Universities for the PhD (FPI) grant she has received.Peer ReviewedPostprint (published version

Visible and extended near-infrared multispectral imaging for skin cancer diagnosis

With the goal of diagnosing skin cancer in an early and noninvasive way, an extended near infrared multispectral imaging system based on an InGaAs sensor with sensitivity from 995 nm to 1613 nm was built to evaluate deeper skin layers thanks to the higher penetration of photons at these wavelengths. The outcomes of this device were combined with those of a previously developed multispectral system that works in the visible and near infrared range (414 nm⁻995 nm). Both provide spectral and spatial information from skin lesions. A classification method to discriminate between melanomas and nevi was developed based on the analysis of first-order statistics descriptors, principal component analysis, and support vector machine tools. The system provided a sensitivity of 78.6% and a specificity of 84.6%, the latter one being improved with respect to that offered by silicon sensors

Visible and extended near-infrared multispectral imaging for skin cancer diagnosis

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Hyperspectral imaging for skin cancer and blood disorders diagnosis

Hyperspectral imaging is a novel technology for acquiring an image at a large number of wavelengths, thus allowing the study of spectral and spatial details of a sample under analysis. This technology has emerged as a promising imaging modality to be used as a diagnostic tool in several medical applications where spectral information is relevant. In this paper, we outline our most recent achievements in this field. Firstly, hyperspectral imaging systems developed to improve non-invasive diagnosis of skin cancer, consisting of digital silicon and InGaAs cameras and light emitting diodes, are described. Secondly, we present our last advances using hyperspectral technology together with confocal microscopy to improve the diagnosis of blood diseases, in particular, hemoglobinopathies such as thalassemia and cell membrane diseases such as hereditary spherocytosis. Finally, new insights on these topics are discussed.This project has been funded by the Agencia Estatal de Investigación (AEI) (PID2020-112527RB-I00 / AEI / 10.13039/501100011033). L R-B thanks the Ministry of Science, Innovation and Universities for the PhD (FPI) grant she has received.Peer ReviewedPostprint (author's final draft

Multispectral imaging system based on light-emitting diodes for the detection of melanomas and basal cell carcinomas: a pilot study (Erratum)

This erratum corrects the error of an omitted author in doi: http://dx.doi.org/10.1117/1.JBO.22.6.065006This article [J. Biomed. Opt. 22(6), 065006 (2017)] was originally published online on 29 June 2017. An author was accidentally omitted from the author list. Josep Malvehy contributed to the concept and design, data collection, analysis and interpretation, and obtained funding. He has been added to the author list as shown above. This article was corrected online on 20 July 2017

Membrane protein detection and morphological analysis of red blood cells in hereditary spherocytosis by confocal laser scanning microscopy

In hereditary spherocytosis (HS), genetic mutations in the cell membrane and cytoskeleton proteins cause structural defects in red blood cells (RBCs). As a result, cells are rigid and misshapen, usually with a characteristic spherical form (spherocytes), too stiff to circulate through microcirculation regions, so they are prone to undergo hemolysis and phagocytosis by splenic macrophages. Mild to severe anemia arises in HS, and other derived symptoms like splenomegaly, jaundice, and cholelithiasis. Although abnormally shaped RBCs can be identified under conventional light microscopy, HS diagnosis relies on several clinical factors and sometimes on the results of complex molecular testing. It is specially challenging when other causes of anemia coexist or after recent blood transfusions. We propose two different approaches to characterize RBCs in HS: (i) an immunofluorescence assay targeting protein band 3, which is affected in most HS cases and (ii) a three-dimensional morphology assay, with living cells, staining the membrane with fluorescent dyes. Confocal laser scanning microscopy (CLSM) was used to carry out both assays, and in order to complement the latter, a software was developed for the automated detection of spherocytes in blood samples. CLSM allowed the precise and unambiguous assessment of cell shape and protein expression.This publication is part of the project PID2020-112527RBI00, funded by CIN/AEI/10.13039/501100011033. Laura Rey-Barroso thanks the Ministry of Science, Innovation and Universities for the PhD (FPI) grant she has received (DPI2017-89414-R). The current study has been funded by the Spanish National Agency of Investigation (AEI).Peer ReviewedPostprint (published version

Evaluación de la microscopía confocal como herramienta de diagnóstico en enfermedades de los glóbulos rojos

La esferocitosis hereditaria (EH) provoca mutaciones en las proteínas de la membrana de los glóbulos rojos (GRs) que hacen que las células se deformen y se vuelvan demasiado rígidas para poder viajar a través de los vasos sanguíneos. Estas células anormales se destruyen masivamente en el bazo, lo que provoca anemia grave y esplenomegalia además de ictericia y cálculos biliares. El diagnóstico de la EH requiere la realización de complejas pruebas moleculares en la mayoría de casos. Para evitar la realización de dichas pruebas, la microscopía confocal espectral podría utilizarse en el diagnóstico de estas y otras enfermedades. En este estudio, se tiñó la membrana de los GRs con tintes de color e inmunomarcadores, y, bajo un microscopio Leica TCS8, se analizaron los posibles defectos de membrana expresados como diferencias en color y forma en pacientes con EH