title: Performance measurement of PSF modeling reconstruction (True X) on Siemens Biograph TruePoint TrueV PET/CT.
abstract: OBJECTIVE
  The Siemens Biograph TruePoint TrueV (B-TPTV) positron emission tomography (PET) scanner performs 3D PET reconstruction using a system matrix with point spread function (PSF) modeling (called the True X reconstruction). PET resolution was dramatically improved with the True X method. In this study, we assessed the spatial resolution and image quality on a B-TPTV PET scanner. In addition, we assessed the feasibility of animal imaging with a B-TPTV PET and compared it with a microPET R4 scanner.
  
  
  METHODS
  Spatial resolution was measured at center and at 8 cm offset from the center in transverse plane with warm background activity. True X, ordered subset expectation maximization (OSEM) without PSF modeling, and filtered back-projection (FBP) reconstruction methods were used. Percent contrast (% contrast) and percent background variability (% BV) were assessed according to NEMA NU2-2007. The recovery coefficient (RC), non-uniformity, spill-over ratio (SOR), and PET imaging of the Micro Deluxe Phantom were assessed to compare image quality of B-TPTV PET with that of the microPET R4.
  
  
  RESULTS
  When True X reconstruction was used, spatial resolution was <3.65 mm with warm background activity. % contrast and % BV with True X reconstruction were higher than those with the OSEM reconstruction algorithm without PSF modeling. In addition, the RC with True X reconstruction was higher than that with the FBP method and the OSEM without PSF modeling method on the microPET R4. The non-uniformity with True X reconstruction was higher than that with FBP and OSEM without PSF modeling on microPET R4. SOR with True X reconstruction was better than that with FBP or OSEM without PSF modeling on the microPET R4.
  
  
  CONCLUSIONS
  This study assessed the performance of the True X reconstruction. Spatial resolution with True X reconstruction was improved by 45 % and its % contrast was significantly improved compared to those with the conventional OSEM without PSF modeling reconstruction algorithm. The noise level was higher than that with the other reconstruction algorithm. Therefore, True X reconstruction should be used with caution when quantifying PET data.
authors: Molecular Imaging Research Center, Korea Institute Radiological and Medical Sciences, 75 Nowon-gil, Gongneung-dong, Nowon-gu, Seoul, 139-706, Republic of Korea, redn2000@yonsei.ac.kr.
authors: Young Sub
authors: YS
authors: Lee
authors: Jin Su
authors: JS
authors: Kim
authors: Kyeong Min
authors: KM
authors: Kim
authors: Joo Hyun
authors: JH
authors: Kang
authors: Sang Moo
authors: SM
authors: Lim
authors: Hee-Joung
authors: HJ
authors: Kim
mesh_terms: D000465:Algorithms; D000818:Animals; D005240:Feasibility Studies; D019788:Fluorodeoxyglucose F18; D021621:Imaging, Three-Dimensional / Q000295:instrumentation* / Q000379:methods*; D064847:Multimodal Imaging / Q000295:instrumentation / Q000379:methods; D009374:Neoplasms, Experimental / Q000000981:diagnostic imaging; D019047:Phantoms, Imaging; D049268:Positron-Emission Tomography / Q000295:instrumentation* / Q000379:methods*; D011817:Rabbits; D019275:Radiopharmaceuticals; D051381:Rats; D059629:Signal-To-Noise Ratio; D013848:Thigh / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18