Institute of Fundamental Technological Research

Aim.
The aim of our study was to assess the usefulness of high frequency ultrasonography in the diagnosis of melanoma. Methods. We examined 84 patients with suspicious melanocytic skin lesions, including 19 cases of melanoma. In vivo high-resolution ultrasonography (30 MHz) was performed prior to excision.

Results.
In ultrasound scans early melanomas presented as flat oval or fusiform shaped structures and were clearly demarcated, while advanced melanomas were characterized by a roundish shape with less distinct borders. The ultrasonographic thickness of in situ melanomas ranged from 0.02 to 0.85 mm. In the case of invasive tumors, the mean thickness evaluated by high frequency ultrasonography was 10.7% higher compared to the Breslow Score (1.44±0.8 mm and 1.3±0.88 mm, respectively). In all melanomas of Breslow Score of 1 mm or more ultrasound also indicated a Breslow Score of 1 mm or more.

Conclusion.
High frequency ultrasound examination has limited value in differential diagnosis of melanoma, but it gives a clear picture of the size and depth of the tumor. The method should be used as a complementary method (after dermoscopy and, where applicable, reflectance confocal microscopy) in preoperative evaluation of the tumor. In some cases of locally advanced melanoma, ultrasound examination may allow to reduce the number of surgical procedures and favor the decision of a one-time surgical treatment (removal of primary tumor and sentinel lymph node biopsy at the same time).

Dermoscopy - Diagnosis - Melanoma - Microscopy, confocal - Ultrasonography

Typical diagnostic process in dermatology includes clinical assessment, dermoscopic and histopathologic examination. Microsonography was initiated in seventies and much progress in the development of high-frequency scanners occurred since that time. The aim of the study was the assessment of high frequency ultrasonography in dermatologic diagnostics. Material and methods. Examination was performed with 30 MHz ultrasound transducer with 0,1 mm resolution and 7 mm penetration. We examined patients with benign and malignant neoplasms, cicatrical alopecia and morphea. Results. Sonographically, the normal skin is composed of three layers: an epidermal entry echo, dermis and subcutaneous tissue. In healthy skin we can image small hypoechoic areas which correspond to hair folicules, vessels and sebaceous glands. Most of small skin neoplasmatic lesions were hypoechogenic and homogeneous on examination. Extensive lesions were multicomponent with normo-, hypo- and anechogenic structures. The assessment of lesion’s boarders allows sometimes to conclude the invasiveness of the lesion. Areas of skin with clinically visible atrophy showed diffuse increasing of echogenicity. In early lesions, without accomplished fibrosis, diffuse decreasing of echogenicity can be observed, that is probably caused by inflammatory infiltration. In comparison to the healthy skin, the ultrasound scan of sclerotic skin shows a wide entry echo and highly reflective, thicker dermis as a result of the collagen fibers accumulation. Conclusions. Above data suggest that ultrasonographic examination may be a valuable dermatologic diagnostic tool that completes classical dermatologic diagnostics and helps to plan the treatment.

high frequency ultrasonography, benign neoplasms, malignant neoplasms, cicatrical alopecia, morphea