Quantification in Nuclear Medicine: Interest of the in SPECT-CT Scan SUVspect in Thea New Generation of Gamma-cameras With Semiconductor. Data Collection for the Constitution of an Observatory of Scintigraphies

Since 2017, a revolution began in the departments of nuclear medicine, with the routine use of gamma-cameras with semiconductor. These gamma-cameras (which obtained the CE-marking in 2016), offer a technological breakthrough by providing an additional information. They allow "to quantify" for the 1st time in clinical routine conditions, the quantity of radioactivity, by means of a "SUVspect", in a volume of interest, while respecting the recommendations of best practice of the learned societies of French nuclear medicine (SFMN), European (EANM) and American (SNM), without injection of tracer nor acquisition or additional irradiation. The SUVspect is therefore an indicator of the quantity of tracer in a given volume of acquisition.

Until now, the interpretation criteria of scintigraphies are based on the homogeneity of distribution of a tracer in the explored organ (for single organs such as the heart or the thyroid, for example) or in the asymmetry of distribution of the tracer (for the double organs, such as the kidney or the joints).

This new gamma-camera allows to study the distribution of the radio-tracers in "list" mode, allowing to retrospectively reconstruct the images in various ways (for example, by modifying the size of the matrix of acquisition, the energy windows, the time of acquisition). Therefore, we can simulate and propose modifications in current procedures.

Every patient referred to our department of nuclear medicine to undergo a scintigraphy with a tracer of nuclear medicine (with a marketing authorization) can, while benefiting from an examination by this gamma-camera, to be the object of this study, and to profit from this additional information.

So, without changing the diagnosis or the usual care, we wish to take advantage of this additional information to improve the criteria of interpretation of our examinations.

This possibility being new, there is no available bibliography (our department is the 5th department of nuclear medicine in Europe to equip itself with this large field-of-view gamma-camera CZT, the DNM 670, made by General Electric), while 2961 articles speak about the SUVmax (in PET) in Pubmed.