Mapping the Distribution of Melanin Concentration in Different Fitzpatrick Skin Types Using Hyperspectral Imaging Technique

Abstract

Measuring skin melanin concentration in order to assess skin phototype according to Fitzpatrick's classification is a constant research goal. In this study, a new approach for assessing skin melanin concentration based on hyperspectral imaging combined with an appropriate analytical model that exploits specific spectral bands to generate maps of melanin content distribution on different Fitzpatrick skin phototypes is presented. Hyperspectral images from the proximal inner side of the forearms of 51 young volunteers covering the first four classes of Fitzpatrick's phototypes were acquired using a hyperspectral imaging system. The images were analyzed using a modified Beer–Lambert law that segregates the contribution of melanin from the other constituents to the skin absorption spectrum. The performance of the model was evaluated using the coefficient of determination (r‐squared). The results revealed that the approach proposed in this study generated accurate melanin concentration distribution maps that allowed a correct classification of skin phototype. In conclusion, the proposed approach for assessing skin melanin concentration proved to be very reliable for classifying skin phototypes, and, as it provides maps that are easily read, it has the advantage of a possible extension of its applications to other research concerning skin pigmentation.

Hyperspectral imaging‐based erythema classification in atopic dermatitis

“…Consequently, various studies have been conducted using HSI in medicine recently. 26,27 Currently, in clinical practice, skin lesions are visually recognized and evaluated by specialists, primarily using qualitative scales. VA is subjective because it depends on the dermatologist's experience, color perception and eye sensitivity, observation conditions (light intensity, light color temperature, and light angle), and the patient's emotional state.…”

“…Additionally, in terms of human tissues, it can distinguish between healthy and lesioned tissues by extracting their unique features and yield non‐invasive, painless, and rapid results that do not require separate preparation by the patient for the test. Consequently, various studies have been conducted using HSI in medicine recently 26,27 …”

Hyperspectral imaging to accurately segment skin erythema and hyperpigmentation in cutaneous chronic graft‐versus‐host disease

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