Clinical usefulness of thyroid imaging by means of X-ray fluorescence

Iodine storage is an important thyroid function which has been difficult to estimate by simple means up to now. The introduction of the X-ray fluorescence technique makes this assessment possible on a large scale, with a minimum radiation burden and no more discomfort for the patient than classical imaging with radioisotopes. Its implementation has resulted in the better understanding of some aspects of thyroid physiopathology. This paper deals with the clinical utility of the method: the visualization of stable iodine and, most important, its quantification contribute significantly, sometimes fundamentally, to a better diagnosis with its therapeutic implications.