核医学検査に用いる装置の基礎 - nm.jsrt.or.jp

1 72 16 Basic Lecture of an Imaging Device in Nuclear Medicine spect PET CT MRI US spect Anger Anger Anger spect Anger spect 20 spect spect -CT spect spect spect

2 PET Time-of-Flight TOF TOF TOF S/N JIRA NEMA 5 72 17 2007 2012 JIRA JESRA NEMA IEC NEMA JESRA PET spect spect (RI) RI s CountsPosition spect mm)99m )CdTe NaI 2 mm 4 mm spect Tc-99m 90% spect mm) mm)

3 Tc -9 FOV EM 800100012001400tsABFBPCold Spot -2000200400600 ABcounpositionFBPOSEM(Itr 2, Subset 10)OSEM(Itr 10, Subset 10)18 OSEM OSEM Sorenson ChangIterativeChangOS-EM FBPFBP3D OSEM AB CPositionFBP3D OSEMFBP3 DOSEMABCABC AB =10mm 7mm@FWHM 12mm@FWHM 17mm@FWHM ABPET 511keV Photon2 ( ) Positron Emitter(Radio Nuclide)PositronElectron511keV PhotonPET BGO GSO LSO NaI(Tl)

4 G/cm3 75 59 65 51 mm /MeV 8200 10000 30000 38000 ns 300 60 40 230 No No No Yes Yes No Yes No nm 480 430 420 410 19 mm LSONaI(Tl) cm /MeV BGO8200 : Time TimeTOF(Time-of-Flight)2 LOR ML-EM TOF vs.

5 Non-TOF TOF TOF TOF, 120sec/bedBG; , Hot:BG=4:1 Iter;3, Sub;10, Gaussian 5mmNon-TOF, 300sec/bedBG; , Hot:BG=4:1 Iter;2, Sub;20, Gaussian 5mmTOF -on vs off (JP delivery protocol)TOF PET TOF TOFIter:2, Sub:10, , , 120sec/bed , SUV 0-5 Non-TOFIter:2, Sub:20, G:6mm Steinberg Diagnostic Medical Imaging Centers20CT PET CT PET CT PET CT PET CT PET CT PET CT PET PET NEMA 2007 2012 1 Mcps / C57 Tl / Co-57 Tl-201 Focus spect PET

6 IEC NEMA JESRA NEMA NU1 2007 2012 Defective pixels Fraction of defective clusters 5x5 Wj=1 W =0 NEMA NU 1-2012 Performance Measurements of Gamma Cameras spect PET IEC NEMA JESRA 37mm28mm22mm10mm13mm17mmIEC 61675 21