Normal Ultrasound Anatomy of the Skin, Nail, and Hair

The document from January 1, 2018, details the normal ultrasound anatomy of the skin, nail, and hair, as well as adjacent structures and other skin-related anatomical features. It describes the skin as having three layers: the hyperechoic epidermis, the less bright hyperechoic dermis, and the hypoechoic hypodermis. The nail is characterized by a hyperechoic bilaminar plate and an anechoic space, while hair follicles are seen as hypoechoic oblique bands. Lymph nodes, tendons, muscles, and nerves are also described with their typical ultrasound appearances. Additionally, the document outlines the ultrasound morphology of bursae, cartilage, joints, vessels, salivary glands, and mammary glands, noting that bursae are usually invisible unless inflamed, cartilage appears hypoechoic, and vessels are anechoic with distinct flow patterns. It highlights the importance of understanding normal anatomy to distinguish it from abnormalities and avoid misdiagnosis, especially since anatomical variants can sometimes resemble pathological conditions.