title: Performance characteristics obtained for a new 3-dimensional lutetium oxyorthosilicate-based whole-body PET/CT scanner with the National Electrical Manufacturers Association NU 2-2001 standard.
abstract: This article reports the results of performance measurements obtained for the lutetium oxyorthosilicate (LSO)-based whole-body PET/CT scanner Biograph 16 HI-REZ with the National Electrical Manufacturers Association (NEMA) NU 2-2001 standard. The Biograph 16 HI-REZ combines a multislice (16-slice) spiral CT scanner with a PET scanner composed of 24.336 LSO crystals arranged in 39 rings. The crystal dimensions are 4.0x4.0x20 mm3, and the crystals are organized in 13x13 blocks coupled to 4 photomultiplier tubes each. The 39 rings allow the acquisition of 81 images 2.0 mm thick, covering an axial field of view of 162 mm. The low- and high-energy thresholds are set to 425 and 650 keV, respectively, acquiring data within a 4.5-ns-wide coincidence window.
  
  
  METHODS
  Performance measurements for the LSO-based PET/CT scanner were obtained with the NEMA NU 2-2001 standard, taking into account issues deriving from the presence of intrinsic radiation.
  
  
  RESULTS
  The results obtained with the NEMA NU 2-2001 standard measurements were as follows: average transverse and axial spatial resolutions (full width at half maximum) at 1 cm and at 10 cm off axis of 4.61 (5.10) mm and 5.34 (5.91) mm, respectively; average sensitivity of 4.92 counts per second per kilobecquerel for the 2 radial positions (0 and 10 cm); 34.1% system scatter fraction; and peak noise equivalent count (NEC) rates of 84.77 kilocounts per second (kcps) at 28.73 kBq/mL (k=1 in the NEC formula; noiseless random correction) and 58.71 kcps at 21.62 kBq/mL (k=2; noisy random correction).
  
  
  CONCLUSIONS
  The new integrated PET/CT system Biograph 16 HI-REZ has good overall performance, with, in particular, a high resolution, a low scatter fraction, and a very good NEC response.
authors.affiliation: Health Physics Department, Azienda Ospedaliera Maggiore della Carità, Novara, Italy. marco.brambilla@maggioreosp.novara.it
authors.forename: Marco
authors.initials: M
authors.lastname: Brambilla
authors.forename: Chiara
authors.initials: C
authors.lastname: Secco
authors.forename: Marco
authors.initials: M
authors.lastname: Dominietto
authors.forename: Roberta
authors.initials: R
authors.lastname: Matheoud
authors.forename: Gianmauro
authors.initials: G
authors.lastname: Sacchetti
authors.forename: Eugenio
authors.initials: E
authors.lastname: Inglese
mesh_terms: D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional / Q000379:methods* / Q000592:standards; D008168:Lung / Q000473:pathology; D008187:Lutetium / Q000737:chemistry*; D019047:Phantoms, Imaging; D049268:Positron-Emission Tomography / Q000379:methods*; D011786:Quality Control; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D017640:Silicates / Q000737:chemistry*; D013382:Subtraction Technique; D013997:Time Factors; D015898:Tomography Scanners, X-Ray Computed; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000592:standards; D051598:Whole Body Imaging
chemical_list: D017640:Silicates; D008187:Lutetium