Evaluation of Skin Recovery after Fractional CO2 Laser Treatment of Vulvar Lichen Sclerosus Using Multimodal Optical Coherence Tomography

The aim of the study is to demonstrate the effect of fractional CO2 laser treatment on vulvar skin in lichen sclerosus using multimodal optical coherence tomography (MM OCT). The study included 3 clinical cases of vulvar lichen sclerosus (VLS) (histologically classified as early, early with dermal edema, late) and 2 control cases without vulvar pathology. Patients with VLS underwent 3 procedures of fractional CO2 laser treatment with an interval of 30-40 days. In patients without vulvar pathology, the MM OCT examination was performed once, in patients with VLS it was done at the point of the greatest visible skin damage just before a punch biopsy, immediately after the first laser session, and 1 month after a full course of treatment. Analyzing the case series of vulvar skin recovery 1 month after fractional CO2 laser treatment, it has been found that the recovery depended on the dermal condition before the treatment. In early VLS and early VLS with dermal edema (clinical cases 1 and 2) before the treatment, the MM OCT examination has shown a decreased epidermal thickness, unclear contrast between the epidermis and dermis, a decrease in the values of the OCT signal attenuation coefficient in the dermis, and a sharp reduction in the density of blood and lymphatic vessels. After treatment, the MM OCT examination demonstrated a complete recovery of vulvar skin structure and all quantitative values reached the level characteristic of normal vulvar skin. Before the treatment, a homogenization zone (sclerosis) was clearly visible in the MM OCT images of the dermis in late VLS (clinical case 3). After the treatment, complete recovery of the vulvar skin structure was not observed; the area of sclerosis was preserved; however, visually, there was an increase in the density of blood and lymphatic vessels in the affected area, which almost reached the level of normal vulvar skin. MM OCT can be proposed as a promising non-invasive method for monitoring skin recovery after fractional CO2 laser treatment of VLS.