First experiences with a high-resolution ultrasonic scanner in the diagnosis of malignant melanomas.

The use of high-resolution ultrasonic instruments with transducer frequencies above 8 MHz makes it possible to visualize malignant melanomas of a thickness of more than 0.7 mm. While the sonolucent structure has not permitted the dignity of a lesion to be judged to date, it is easy to determine the maximal tumor thickness as well as infiltration of the subcutis. Thus "low-risk" and "high-risk" melanomas may be differentiated preoperatively according to these parameters. The results are of great use for the operator to plan the extent of his intervention, as well as to select patients for prophylactic regional lymphonodectomy.