Thickness and echogenicity of the skin in children as assessed by 20-MHz ultrasound

BACKGROUND: Skin anatomy and physiology undergo modifications throughout the whole lifespan. In children the skin appears with structural characteristics, as evaluated by histology, which differ from those of adults, especially in the first years of life. OBJECTIVE: The aim of our study was to evaluate skin thickness and echogenicity at different sites in children by 20-MHz ultrasound. METHODS: Eight skin sites of 42 children and 30 young adults were studied with a 20-MHz B scanner. Skin thickness and mean echogenicity were evaluated. The echographic images were processed and segmented by a dedicated program: the 0-30 amplitude interval, which marks the hypoechogenic parts of the tissue, and the 201-255 range, highlighting the hyperreflecting areas, have been selected. RESULTS AND CONCLUSION: Whereas skin thickness shows a gradual increase from birth to adulthood, maturation of the skin leads to variations in the intensity of its echogenicity, depending on the different skin areas. Whereas on the face and the trunk it appears lower in adults with respect to children, a gradual increase can be observed on the limbs with growing age. The distribution of skin reflectivity also greatly varies in different phases of life.