Spectral morphological analysis of skin lesions with a polarization multispectral dermoscope

Abstract

Dermoscopy is the conventional technique used for the clinical inspection of human skin lesions. However, the identification of diagnostically relevant morphologies can become a complex task. We report on the development of a polarization multispectral dermoscope for the in vivo imaging of skin lesions. Linearly polarized illumination at three distinct spectral regions (470, 530 and 625 nm), is performed by high luminance LEDs. Processing of the acquired images, by means of spectral and polarization filtering, produces new contrast images, each one specific for melanin absorption, hemoglobin absorption, and single scattering. Analysis of such images could facilitate the identification of pathological morphologies.

In vivo non‐invasive monitoring of collagen remodelling by two‐photon microscopy after micro‐ablative fractional laser resurfacing

“…This algorithm enhances the contrast for the absorption of haemoglobin, which is contained in blood vessels and exhibits high absorption in the green spectral band. A detailed description of this experimental setup, together with the image analysis algorithms developed and with examples on skin is provided in [56].…”

“…A macroscopic observation of the effects caused by micro-ablative laser resurfacing treatment was performed by using a custom-made dermoscope [56]. The dermoscopic examination allowed monitoring skin appearance during the wound healing process taking place during the first week after treatment.…”

“…In (Figure 3j-m) Blood Contrast images are presented. These images are produced according to a previously developed methodology [56]. Blood Contrast images are specific for haemoglobin absorption, and structures containing haemoglobin appear with dark grey level values and their contrast is enhanced against other absorbing structures.…”

“…This combined technique has been widely used for imaging and characterizing human skin dermis. In particular, it has been used for monitoring collagen alteration in dermal disorders [50] or at the tumour-stroma interface [51][52][53], as well as to monitor skin aging by measuring the collagen/elastic fibres content [54][55][56].…”

Hyperspectral system for Imaging of skin chromophores and blood oxygenation

“…Spectral images of skin and other tissues contain information about the spatial distribution and concentrations of biological chromophores, such as hemoglobin (oxy-/deoxy), melanin, bilirubin, and carotene. 4,5 The combination of a fast and compact hyperspectral camera with a broadband light illumination and neural network-based processing allows for multiparameter estimation of tissue properties. Potential applications of the proposed technique are of high social impact and include monitoring and diagnostics of diabetic ulcer formation, 6 rheumatic complications, 7,8 diagnoses of melanoma and other malignancies, 9 quantitative skin screening, 10 wound healing control, 11 assistance and support of laser surgical and treatment procedures 12 and others.…”