Resumen de Agenesis of the thyroid isthmus.

Mercedes Barbosa Cachorro, Félix Jesús de Paz Fernández, José Antonio Gil Verona, Juan Francisco Pastor Vázquez

• We describe a case of thyroid isthmus agenesis the incidence varies from 5% to 10%). This absence can be explained as an anomaly of embryological development and can be associated with other types of disorganogenesis, such as the absence of a lobe or the presence of ectopic thyroid tissue. In human clinical practica, when an image of the absence of isthmus is found it is necessary to perform a differential diagnosis against other pathologies such the autonomous thyroid nodule, thyroiditis, etc.