Ultrasound appearances of de Quervain's thyroiditis.

De Quervain's thyroiditis can be readily recognised by ultrasound. The sonographic features and previously unreported signs of two such cases are illustrated. One case had typical multiple hypoechogenic areas in the thyroid parenchyma. The other had multiple small areas giving a spotty appearance not previously reported in de Quervain's. Both patients demonstrated remarkable shrinkage of the gland (to 17.4% and 57% of the original presenting volume). We believe this is a useful diagnostic feature of de Quervain's thyroiditis.