Hyperspectral assessment of acne skin exposed to intense pulsed light (IPL) intense pulsed light in acne treatment

Abstract

Background:The mechanism of intense pulsed light action on the skin is based on selective photothermolysis. The light delivered to the tissue is scattered and absorbed by chromophores that absorb a beam of radiation of a specific length. The skin reflectance changes depending on the physiological state of the tissue, as shown by the hyperspectral camera. The aim of the study was to assess the hyperspectral reflectance of acne skin before and after intense pulsed light (IPL) therapy and to compare it with the reflectance of healthy skin. Materials and methods:The study involved 27 volunteers with diagnosed moderate acne. The control group consisted of 20 people without acne lesions. All acne volunteers underwent a series of four treatments using IPL at weekly intervals. The volunteers with acne lesions were photographed before the series of treatments and a week after the 4th treatment.Results: Acne skin shows lower reflectance than healthy skin. Acne skin after IPL therapy is characterized by a higher reflectance compared to acne skin before the therapy and resembles the reflectance of the skin of the control group. A statistically significant difference was found between the acne skin before the treatments and the skin of the control group. Conclusions:The effect of IPL therapy on acne skin is the increase of its reflectance by reducing the number of chromophores, which brings it closer to the reflectance value of healthy skin. Hyperspectral imaging allows for: the evaluation of the treated skin at each stage, a precise selection of the light wavelength depending on the problem, and therefore, for optimizing the number of irradiations and increasing the safety of the therapy.