[Contrast of the grey scale and stable B-scan in the ultrasonic visualization of the thyroid gland].
Thyroid echography can be profitably performed with the stable contrasted B-scan and the gray scale. Both methods are based on the possibility of recording weak echoes from structures inside the gland and so differentiate almost all lesions in a reliable manner. The echo-structural patterns permit the following distinctions to be drawn: uniform distribution of echoes in the normal, hypoplastic and hyperplastic-hypertrophic thyroid. Calcified areas in goitre give distinct, strong echoes, whereas in colloid-cystic goitre there are weak echoes mixed with small empty areas due the cysts. Cystic lesions, too, have empty areas that are well defined, with reinforcement of the posterior wall. In adenoma, there is a uniform, solid area, in which the echoes are evenly distributed internally and the borders are well defined with respect to the unimpaired parenchyma. In acute thyroiditis, the presence of oedema and areas of fibrosis offer sufficiently indicative signs. In tumours, the most typical features are the irregularity of the walls, the distinct attenuation of the beam and the presence of a few, irregular internal echoes. These pictures are almost always peculiar to each situations and thus make echographical investigation of thyroid not only useful, but also indispensable.
D006801:Humans; D008722:Methods; D013959:Thyroid Diseases / Q000175:diagnosis*; D013964:Thyroid Neoplasms / Q000175:diagnosis*; D014463:Ultrasonography
Scala dei grigi e B-scan stabile contrastato nella visualizzazione ultrasonica della tiroide.