Count-enhancement PET Imaging using a 0.4 mm Cross-strip 3D CZT Detector

This paper investigates a cross-strip Cadmium Zinc Telluride (CZT) positron emission tomography (PET) detector, with anode electrode strip width of 0.3 mm x 16.4 mm and cathode strip width of 0.9 mm x 16.4 mm. By utilizing the design of an orthogonal arrangement of cathode and anode, and the ratio of cathode-to-anode signal amplitudes, three-dimensional positioning of gamma photons can be achieved. A set of three-dimensional position calculation formulas is proposed by analyzing the signal of the CZT detector, which can further improve the positioning accuracy. The 3D gamma-ray interaction coordinates are validatedby the signal waveforms. The energy resolutions of single anode, adjacent anode, and non-adjacent anode events for the 0.4 mm CZT detector were found to be 5.3%, 4.6%, and 8.5%, respectively. PET imaging was performed using the 0.4 mm CZT and 1.0 mm LYSO detector with VP-PET geometry. PET imaging was completed on a rotating platform for a 3 mm diameter Na-22 point source. We reconstructed the PET images using both single-anode events and multiple-anode events. Future work will focus on the PET imaging of high-resolution phantom and mouse.