Quantification of Microstructural Changes in the Dermis of Elderly Women Using Morphometric Indices of the Skin Surface

Objective: The main objective of this study was the development of a non-invasive mathematical marker of the skin surface, the characteristic length, to predict the microstructure of the dermis. This marker, at the individual level, is intended to provide the biological age of the patient in the context of personalised medicine for the elderly. Study design: To validate this hypothesis, a clinical study was conducted on 22 women over 60 years old from a population of osteoporotic subjects who sustained a femoral neck fracture: a morphological analysis of the skin surface was performed on the patient’s forearm and quantitatively compared with microarchitectural parameters of the dermis. Major results: The Elastin-to-Collagen ratio measured on dermis samples ranged between 0.007 and 0.084, with a mean of 0.035 ± 0.02. The surface characteristic length ranged between 0.90 and 2.621, with a mean of 0.64 ± 0.51. A very strong correlation was found between this characteristic length and the Elastin-to-Collagen ratio (r = 0.92). Conclusions: This study proposes an original diagnostic tool based on morphometric indices of the skin surface and shows a direct quantitative relationship with the dermis microarchitecture and its collagen and elastin content. The proposed method allows reliable and easy access to the intrinsic ageing of the dermis, which would be a strong biomarker in a personalised collagen treatment approach.