- 期刊
Apply Point Spread Functions in PET/CT Image Reconstruction: Impact on Standardized Uptake Value
並列摘要
Background: Point spread functions (PSF) describe the response of an imaging system to a point source in the field of view. PSF can be used to improve image spatial resolution and signal-to-noise ratio. The aim of this study was to evaluate the impact of PSF on standardized uptake values (SUVs) in clinical PET studies.Methods: We enrolled 19 patients (11 men and 8 women, age 58.2 ± 13.4 years) with malignancy underwent F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) studies for clinical indications into this retrospective study. FDG-PET/CT studies were performed on a Siemens Biograph 64 PET/CT system. Each scan was processed with two reconstruction methods, 3D-OSEM and ”3D-OSEM + PSF”. An automatic volume-of-interest method with threshold of SUV 2.5 was used to measure SUVmax, SUVmean, and tumor volume.Results: Forty hypermetabolic lesions were identified. The SUVmax with 3D-OSEM and ”3D-OSEM + PSF” reconstruction were 6.22 ± 2.71 and 6.64 ± 2.99 respectively. The SUVmean with 3D-OSEM and ”3D-OSEM + PSF” reconstruction were 3.74 ± 0.86 and 3.95± 0.89 respectively. Both of the SUVmax and SUVmean were significantly higher with PSF incorporated into the reconstruction algorithm (both p＜0.01). The SUVmax and SUVmean were raised on average by 6.49% and 5.89% respectively. The hypermetabolic tumor volumes with 3D-OSEM and ”3D-OSEM + PSF” reconstruction were 16.34 ± 33.16 cm^3 and 14.66 ± 29.19 cm^3 respectively. The tumor volume was significant smaller with ”3D-OSEM + PSF” reconstruction (p＜0.01).Conclusion: The impact of PSF on SUV measurement was significant in clinical FDG-PET studies. Incorporating PSF into the PET image reconstruction algorithm results in higher SUV measurements and smaller hypermetabolic volume.