Agro-Industry and Health Protection, Radiation Protection Institute ENEA-Italian National Agency for New Technologies, Energy and the Environment, Research Centre of Saluggia, Department of Biotechnologies strada per Crescentino 41-13040 Saluggia (VC) Italy
Helsinki University Central Hospital Department of Oncology Stenbäckinkatu 9 00290 Helsinki Finland
University of Turin Department of Experimental Physics via Pietro Giuria 1 10125 Turin Italy
SPECT studies are sensitive but inaccurate means through which to analyze small volumes such as, for instance, remnant tissues
after thyroidectomy. We studied the relation between known volumes (0.1–10 cm3) and volumes measured with SPECT studies and using solutions of four different isotopes: 99mTc, 117mSn, 111In, 131I. The curves we determined were tested on SPECT images of two patients treated with 131I. Our work suggests the possibility to evaluate the small remnant mass using calibration curves specific to the system of
image acquisition. However, it is necessary to extend the study to a larger number of patients.