ABSTRACT
Optical inspection of skin is the most common method used in dermatology to identify suspicious skin lesions and to evaluate the success of therapies and evolution of skin diseases. In conventional dermatoscopy and video dermatoscopy, investigations are supported by technical instruments. However, the information that is obtained under these conditions, is limited to the skin surface and uppermost skin layers, but it still is the ‘‘gold standard’’ for skin tumor classification. Medical imaging systems make use of different kinds of rays, waves, and physical phenomena (light, X rays, electromagnetic waves, nuclear magnetic resonance, ultrasound, etc.) to noninvasively obtain information about tissue for diagnostic. With these modalities, organs and tissue can be examined which are otherwise invisible. There is also the conceptual benefit that different kind of information about tissue is obtained. Unlike in many other medical disciplines, the development and utilization of noninvasive imaging techniques has only slowly advanced in dermatology. A major reason for this is that the skin is directly accessible to the physician and that the relatively small skin structures require microscopic, high-resolution imaging techniques that are challenging to be designed and implemented. Sonography, i.e., ultrasound imaging, has many potential benefits compared to modalities such as optical coherence tomography, high-resolution magnetic resonance imaging and confocal laser scanning microscopy. It is easy to apply and inexpensive, and dermatologists have already gained a lot of experience in the field of skin sonography.
