The Clinical Value Of High-frequency Ultrasound In Dermatology

Purpose: This study discussed the diagnosis of skin diseases by high-frequency ultrasound, which provided a non-invasive quantitative basis for the diagnosis and treatment on skin diseases.Methods:Firstly, 50 healthy volunteers were involved from 20 to 40 years old in this study, and their ultrasound image data were obtained on epidermis and dermis lay er on forehead, opisthenar, back, anterior portion, chest and cheek, respectively. Secon dly, we examined the different lesions of 50 patients with skin diseases, including co mmon warts, acne patients, patients with soft fibroma, convex type mole and basal cel l carcinoma patients. The size, shape, depth and blood supply of the lesions were mea sured and summarized with sonographic characteristics.Results:High-frequency ultrasound can clearly identify the skin epidermis layer, the dermis structure and the subcutaneous tissue structure. Epidermis shows linear strong echo under ultrasonic, while dermis presents band low echo under ultrasonic. A relatively thin bright line can be found between the dermis and subcutaneous tissue layer, and the subcutaneous tissue shows heterogeneous low echo.High-frequency ultrasound reveals that the skins’ thickness in different parts is of difference among these healthy volunteers. By comparison of the thickness of epidermis and dermis: the thickest one is the back skin, while the thinnest one is the opisthenar skin. But the hand back skin is very pachylosis, and the dermis is slightly thicker than other parts of the skin. The order of thickness is as following: back > Anterior > chest > cheek > forehead > opisthenar.The ultrasonic images of common warts: the lesions of the part skin is thickened, the deep lesions violate the dermis, and the shape is good, the edge is smooth; most blood flow signal is not obvious, and few blood flow signal is rich. The ultrasonic images of acne: the epidermis is rough, the shape is structured, the edge is smooth, and there is no blood flow signal. The ultrasonic images of soft fibroma: the most surface of the lesions is smooth, it merely violate the dermis, the edge is clear and structured, the inside echo is uniform, there is no blood flow signal. The ultrasonic images of convex type mole: the epidermis is rough and unevenly thickened, the basement of the lesions violates the dermis, the others violate subcutaneous tissue, there is a few of blood flow signal. The ultrasonic images of basal cell carcinoma: the surface of the lesions is not smooth, the epidermis are thickened obviously, the shape is irregular, the inside echo is low and inhomogeneous, it is part with acoustic shadow, the blood flow signal is rich.Conclusion: High-frequency ultrasound can clearly show the structure of the skin layers. This method is suitable for repeated dynamic observation and non-invasive. According to ultrasound images, we can monitor the change process of clinical pathology, and diagnose the skin diseases qualitatively and quantitatively. We can understand the relationship between location, depth, range of the lesion and the surrounding tissues, and monitor the therapeutic effect of skin diseases treatment. Before operation, it can help clinicians to determine the boundary of skin cancer surgery. With the development of ultrasound technologies, the resolution of high frequency ultrasound will get a more improvement. It will become an indispensable diagnosis means for dermatologist, combining with pathology, optical microscope.