A Comparative Pilot Study on Ultraviolet‐induced Skin Changes Assessed by Noninvasive Imaging Techniques in Vivo

Abstract

The effects of acute and chronic ultraviolet (UV) on the morphology of human skin have been extensively studied ex vivo by means of histological investigations. However, innovative skin imaging techniques enable visualization of micromorphological structures in vivo. We aimed to perform a correlation study evaluating in vivo dose and time dependent skin changes following solar-simulated irradiation using noninvasive techniques such as optical coherence tomography (OCT) and confocal laser scanning microscopy (CLSM). The forearms of 10 healthy subjects were exposed to 1 minimal erythema dose (MED) and 3 MED of solar-simulated radiation. Noninvasive measurements were performed before and 24 h and 72 h after UV exposures. We demonstrate definite OCT and CLSM findings obtained from UV-exposed skin, including an increase in epidermal thickness (hyperproliferation, acanthosis), a reduction in dermal reflectivity (dermal edema), an increase in brightness of the basal layer (pigmentation), and an increase in vessel diameter within the dermal papillae (vasodilatation). A moderate to strong linear association between the methods employed was observed. In conclusion, noninvasive high-resolution imaging techniques such as OCT and CLSM may be promising tools for photobiological studies aimed at assessing photoadaptive and/or phototoxic processes in vivo. However, larger studies are needed to demonstrate the applicability of the findings presented in this pilot study.

Rapid and accurate estimation of blood saturation, melanin content, and epidermis thickness from spectral diffuse reflectance

“…It may also increase or decrease due to external stimuli. For example, UV exposure of human skin has been shown to increase the thickness of the epidermis in addition to increasing its melanin content [56,57]. On the other hand, smoking has been shown to decrease epidermal thickness [55].…”

Review paper The use of reflectance confocal microscopy in selected inflammatory skin diseases

“…It has a wide range of applications, particularly in the diagnosis of neoplastic skin lesions, enabling non-invasive monitoring of treatment [2][3][4][5][6], in examining skin reactions to external factors (e.g. ultraviolet radiation) [7], as well as planning surgical margins in the course of pre-and intraoperative evaluation [8][9][10]. Reflectance confocal microscopy has also been applied in the study of a number of non-neoplastic skin diseases, especially inflammatory dermatoses.…”

Influence of Repetitive UVA Stimulation on Skin Protection Capacity and Antioxidant Efficacy

“…This is accompanied by an increase in the ultraweak emission of photons (chemiluminescence) normally only associated with basal metabolic processes [4][5][6] . Using in vivo measurements based on ICL-S (induced chemiluminescence of human skin), the duration of a protective effect by 2 weeks of daily topical application of AOs was investigated for up to 4 days.…”