DEDICATED PET SCANNERS FOR BREAST IMAGING

We have used computer simulations to compare two designs for a PET sca nner dedicated to breast imaging with a whole-body PET scanner. The ne w designs combine high spatial resolution, high sensitivity, and good energy resolution to detect small, low-contrast masses. The detectors are position sensitive NaI(T1) scintillators. The first design is a ri ng scanner surrounding the breast and the second consists of two plana r detectors placed on opposite sides of the breast. We have employed s tandard performance measures to compare the different designs: contras t, percentage standard deviation of the background, and signal-to-nois e ratios of reconstructed images. The results of the simulations show that both of the proposed designs have better lesion detectability tha n a whole-body scanner. The results also show that contrast is higher in the ring breast system but that the noise is lower in the planar br east system. Overall, the ring system yields images with the best sign al-to-noise ratios, although the planar system offers practical advant ages for imaging the breast and axilla.