[Thyroid scintigraphy with Fresnel zone plates]

Coded apertures supply a decoupling of resolution and sensitivity in scintigraphic imaging. The reconstructed images are focussed on different planes. The approach presented replaces the conventional collimator by three Fresnel zone plates in order to simulate a complex projection. The theoretical advantages of scintigraphy with coded apertures could be demonstrated in thyroid imaging. Unresolved artifacts and the lack of availability impair its routine use.