[Photoaging of the skin and occupation: correlation between clinical ultrasound and histological findings].

OBJECTIVES: We described the ultrasound (US) signs that can define occupational photoaging of the skin. We also studied the clinical importance of these signs, so as to aid the specialist in the diagnosis and evaluation of "anti-aging" treatments. PATIENTS AND METHODS: The dermis and hypodermis of 180 subjects (6 groups of 15 men and 15 women each), were studied with US test (echograph Sonora 400 MD). We used a 10 MHz probe and recorded the thickness and echogenicity of the dermis and hypodermis. US images were correlated with the histological findings of 60 patients. RESULTS: In skin not exposed to sunlight aging produces an increase in thickness and a reduction in echogenicity, whereas in photoaging there is a reduction in thickness and an increase in echogenicity of the skin. CONCLUSION: Photoaging produces an increase in elastic fibres and consequently hyperechogenicity of the dermis, while, in the advanced phase, the loss of collagen and elastic fibres justify the reduction in thickness and echogenicity of the dermis. These observations allow as to classify the US signs of the photoaging of the skin into four clinical/ultrasound stages.