["Standing waves": differential diagnosis of fibromuscular dysplasia]

We report two recent observations of an angiographic artefact called "standing waves". It results in the same characteristic beaded pictures than fibromuscular dysplasia. It is induced by the angiography catheter and is related to the speed of injection. The possible occurrence of this artefact should be borne in mind whenever the films show dysplastic lesions in more than one artery.