During siascopy, a special wavelength laser beam is used to determine the concentration and localisation of melanin, capillary haemoglobin and collagen in the skin up to the depth of 4 mm, as well as their mutual proportion of connective tissue and pigmented cells separately. The determining of the three-dimensional (3D) pattern of these structures is also possible. Siascopy, as an examination method ensures 97% precision, but, in conjunction with dermoscopy and skin ultrasound methods, the precision of lesion assessment reaches even 100%.