Ultrasonography of nodular and infiltrative lesions of the skin and subcutaneous tissues.

Ultrasonography with high-frequency probes was performed on 80 dermatological patients carrying palpable lesions of the skin. The case list included hemo- and lymphangiomas (16 cases), cysts (13 cases), Kaposi sarcomas (9 cases), and panniculitis (20 cases). All lesions underwent open biopsy and histological examination. Ultrasound yielded technically adequate images in 74/80 cases (93%). Angiomas appeared as multiple transonic cavities separated by hyperechoic septa; cysts were usually echo free or weakly echogenic, with smooth outlines. Kaposi sarcomas corresponded to superficial hypoechoic nodules with blurred margins, while panniculitis appeared as a diffuse thickening of the subcutaneous space. When acute inflammation was present, as in most cases of erythema nodosum, a nonhomogeneous hypoechoic pattern was found.