A dedicated PET scanner for breast cancer

The authors present a design of a PET scanner dedicated to breast imaging. The scanner uses two 2-dimensional position sensitive NaI(Tl) detectors, each with 16 PMTs, placed above and below the breast to detect tumors. The design combines high spatial resolution (3.5 mm) to detect small tumors (≈0.1 cc), high sensitivity and good energy resolution to suppress scatter background and to detect low contrast masses. Additional views of the breast and lymph nodes will be possible. Simulations show that the proposed design has better lesion detectability than a general purpose whole-body PET scanner. Detector thickness, position algorithms, surface treatments of the NaI(Tl) and PMT arrangements will ensure good performance under high countrate conditions and particularly at the edges of the detector closest to the body. A preliminary investigation of different iterative reconstruction algorithms with limited angle datasets show promise in obtaining good image quality and tumor detectability, the scanner´s primary design goals. Simulation results are compared to preliminary phantom measurements