Skin ageing: Clinical aspects and in vivo microscopic patterns observed with reflectance confocal microscopy and optical coherence tomography

Few studies have combined high-resolution, non-invasive imaging, such as standardized clinical images, reflectance confocal microscopy (RCM) and optical coherence tomography (OCT), for age-related skin change characterization according to age groups. This study aimed to correlate clinical manifestations of ageing with skin cytoarchitectural background observed with high-resolution, non-invasive imaging according to age-related skin pattern distribution. A set of 140 non-pathological facial skin images were retrospectively retrieved from a research database. Subjects, aged between 20 and 89, were divided into 7 age groups. Clinical features were explored with VISIA, including hyperpigmentation, skin texture, wrinkles, pores and red areas, quantified and expressed as automated absolute scores. Previously described RCM and OCT epidermal and dermal features associated with ageing were investigated. All features were assessed for distribution and correlation among age groups. Significant direct correlations between age and clinical features were proven for cutaneous hyperpigmentation, skin texture, wrinkles and red areas. As age advances, RCM epidermal irregular honeycomb and mottled pigmentation are more frequently observed and collagen is more frequently coarse, huddled and curled, while the epidermis in OCT is thickened and the dermal density is decreased with more disrupted collagen fibres. RCM and OCT feature changes correlate directly and indirectly as well as correlating directly and indirectly with standardized clinical images. Clinical manifestations of ageing correlate with skin cytoarchitectural background observed with RCM and OCT. In conclusion, complimentary information between standardized clinical images and high-resolution, non-invasive imaging will assist in the development of future studies dedicated to skin ageing assessment and treatment effectiveness.