||Simulation study of a D-shape PET scanner for improved sensitivity and reduced cost in whole-body imaging
Ahmed, Abdella ,
Tashima, HideakiYamaya, Taiga
Physics in Medicine and Biology
4117 , 2017-04
Much research effort is being made to increase the sensitivity and improvethe imaging performance of positron emission tomography (PET) scanners.Conventionally, sensitivity can be increased by increasing the number ofdetector rings in the axial direction (but at high cost) or reducing the diameterof the scanner (with the disadvantages of reducing the space for patients anddegrading the spatial resolution due to the parallax error). In this study, weproposed a PET scanner with a truncated ring and an array of detectors thatcan be arranged in a straight line below the bed. We called this system ‘D-PET’as it resembles the letter ‘D’ when it is rotated by 90° in the counterclockwisedirection. The basic design idea was to cut the unused space under the patient’sbed; this area is usually not in use in clinical diagnosis. We conducted MonteCarlo simulations of the D-PET scanner and compared its performance witha cylindrical PET scanner. The scanners were constructed from 4-layer depthof-interaction detectors which consisted of a 16 × 16 × 4 LYSO crystal arraywith dimensions of 2.85 × 2.85 × 5 mm3. The results showed that the D-PEThad an increase in sensitivity and peak-NECR of 30% and 18%, respectively.The D-PET had low noise in the reconstructed images throughout the fieldof-view compared to the cylindrical PET. These were achieved while keepingsufficient space for the patient, and also without a severe effect on the spatialresolution. Furthermore, the number of detectors (and hence the cost) of theD-PET scanner was reduced by 12% compared to the cylindrical PET scanner.