High-Frequency Ultrasound of Skin Tumors

For a long time modern imaging techniques played only a minor role in dermatology. This was due to the fact that the skin is freely accessible to the examiner’s sensory organs. There was no need to use special auxiliaries for its presentation. The success of noninvasive visualization methods in other specialist medical areas has animated researchers to apply these diagnostic techniques to the skin and associated pathological changes in order to obtain further information. Two aims appear particularly worth pursuing in the field of dermatological oncology: increasing the accuracy of differential diagnosis and improving therapy planning in the case of malignant skin growths. Given the rising case rate of malignant skin tumors in recent decades, priority was granted to this development [69]. Sonography has emerged as one of the prime techniques among noninvasive diagnostic methods. After first experiments in dermatology [1,76], sonography was evaluated by several study groups on a wide range of different skin diseases. Both higher frequency A scan equipment [1, 6, 12, 32, 48, 62,, 89–95, 97, 101, 102] and lower frequency B-scan equipment adopted from other areas of specialization were used. A “water cushion” proved to be an adequate means of ensuring an absence of air bubbles and, therefore, of providing interference-free probe-to-specimen contact between the ultrasonic waves and the skin [2, 59, 60, 105]. The benefits of the sonographic technique, such as high reproducibility, noninvasive measurement of thickness, infinite repeatability, immediate assessability, additional information about morphology, spread and contiguous relationships, scope for progress and therapy monitoring, were recognized at an early stage.