Exploration des nodules thyroïdiens : rôle de l'échographie préopératoire

Ultrasonography is the evidence-based diagnostic method for thyroid nodules. The account has to specify the technical used, and has to exactly describe the echogenicity of the thyroid, the feature of the nodules (number, size, echostructure, echogenicity, edges), and the presence or absence of lymph nodes. The malignancy criteria of thyroid nodules are: (1) hypoechoic solid nodule, (2) presence of internal microcalicifications, (3) ill-defined–irregular edges or absence or breaking of the peripheral halo. The nodes' criteria of malignancy are: (1) diameter of 1 cm or more, (2) clear hypoechoic pattern or non-homogeneous pattern, with alternating hypoechoic and hyperechoic areas, (3) cystic appearance (4) presence of internal calcifications (5) rounded shape with increased anteroposterior diameter, (6) long/short diameter ratio higher than 0.7, (7) absence of hilum. When these criteria are present, a histological diagnosis has to be performed. They could change the operative procedure in the patients.