Bremsstrahlung SPECT Imaging of in vivo Distribution of ~(32)P-phosphours

It is important to monitor the in vivo distribution of pure Beta-emitter used for therapeutic purposes. This study used Bremsstrahlung SPECT imaging to assess the in vivo distributio of 32P-phosphours in tumor patients. Material and methods:SPECT imaging in 23 patients of tumor receiving local 32P internal radiation treatment was carried out with the acquisition energy window set at Bremsstrahlung peak of 32P. The Bremsstrahlung peak of 32P was predetermined by experiment and verified by in vivo imaging. Results: Bremsstrahlung peak of 32P-phosphours was found centered at 78.4kev. The quantity of 32P(Y, MBq/ml) could be calculated via the SPECT image count(X, cts/pix/slice) in a formulation of Y= -0.457+0.311X. The distribution, and quantification of 32P, thus the absorbed radiation dose, in the 23 cases could be calculated. Conclusion :It is feasible to use Bremsstrahlung SPECT imaging technique for monitoring 32P-phosphours treatment.