title: Design study of a high-resolution breast-dedicated PET system built from cadmium zinc telluride detectors.
abstract: We studied the performance of a dual-panel positron emission tomography (PET) camera dedicated to breast cancer imaging using Monte Carlo simulation. The proposed system consists of two 4 cm thick 12 x 15 cm(2) area cadmium zinc telluride (CZT) panels with adjustable separation, which can be put in close proximity to the breast and/or axillary nodes. Unique characteristics distinguishing the proposed system from previous efforts in breast-dedicated PET instrumentation are the deployment of CZT detectors with superior spatial and energy resolution, using a cross-strip electrode readout scheme to enable 3D positioning of individual photon interaction coordinates in the CZT, which includes directly measured photon depth-of-interaction (DOI), and arranging the detector slabs edge-on with respect to incoming 511 keV photons for high photon sensitivity. The simulation results show that the proposed CZT dual-panel PET system is able to achieve superior performance in terms of photon sensitivity, noise equivalent count rate, spatial resolution and lesion visualization. The proposed system is expected to achieve approximately 32% photon sensitivity for a point source at the center and a 4 cm panel separation. For a simplified breast phantom adjacent to heart and torso compartments, the peak noise equivalent count (NEC) rate is predicted to be approximately 94.2 kcts s(-1) (breast volume: 720 cm(3) and activity concentration: 3.7 kBq cm(-3)) for a approximately 10% energy window around 511 keV and approximately 8 ns coincidence time window. The system achieves 1 mm intrinsic spatial resolution anywhere between the two panels with a 4 cm panel separation if the detectors have DOI resolution less than 2 mm. For a 3 mm DOI resolution, the system exhibits excellent sphere resolution uniformity (sigma(rms)/mean) < or = 10%) across a 4 cm width FOV. Simulation results indicate that the system exhibits superior hot sphere visualization and is expected to visualize 2 mm diameter spheres with a 5:1 activity concentration ratio within roughly 7 min imaging time. Furthermore, we observe that the degree of spatial resolution degradation along the direction orthogonal to the two panels that is typical of a limited angle tomography configuration is mitigated by having high-resolution DOI capabilities that enable more accurate positioning of oblique response lines.
authors.affiliation: Department of Radiology, Molecular Imaging Program, Stanford University School of Medicine, Stanford, CA 94305, USA. haopeng@stanford.edu
authors.forename: Hao
authors.initials: H
authors.lastname: Peng
authors.forename: Craig S
authors.initials: CS
authors.lastname: Levin
mesh_terms: D016880:Anisotropy; D001940:Breast / Q000000981:diagnostic imaging*; D002104:Cadmium; D004867:Equipment Design / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D017785:Photons; D049268:Positron-Emission Tomography / Q000295:instrumentation*; D013691:Tellurium; D013997:Time Factors; D015032:Zinc
chemical_list: C474490:CdZnTe; D002104:Cadmium; D015032:Zinc; D013691:Tellurium
references.citation: J Mammary Gland Biol Neoplasia. 2006 Apr;11(2):103-11
references.pmid: 17053979
references.citation: Phys Med Biol. 1994 Mar;39(3):631-42
references.pmid: 15551604
references.citation: Radiology. 1986 Aug;160(2):295-8
references.pmid: 3523590
references.citation: N Engl J Med. 2004 Jul 29;351(5):427-37
references.pmid: 15282350
references.citation: Phys Med Biol. 2008 Feb 7;53(3):637-53
references.pmid: 18199907
references.citation: Radiol Clin North Am. 2004 Nov;42(6):1017-32, vii
references.pmid: 15488555
references.citation: J Magn Reson Imaging. 2001 Jun;13(6):868-75
references.pmid: 11382946
references.citation: Technol Cancer Res Treat. 2005 Feb;4(1):55-60
references.pmid: 15649088
references.citation: Phys Med Biol. 2007 Jul 7;52(13):3753-72
references.pmid: 17664575
references.citation: Breast. 2006 Feb;15(1):29-38
references.pmid: 16002292
references.citation: Phys Rev Lett. 1995 Jul 3;75(1):156-159
references.pmid: 10059139
references.citation: Ann Surg Oncol. 2003 Jan-Feb;10(1):86-91
references.pmid: 12513966
references.citation: Med Phys. 2000 Aug;27(8):1943-54
references.pmid: 10984240
references.citation: Br J Radiol. 2002 Oct;75(898):789-98
references.pmid: 12381687
references.citation: Phys Med Biol. 2004 Oct 7;49(19):4543-61
references.pmid: 15552416
references.citation: Surg Today. 2005;35(9):720-4
references.pmid: 16133665
references.citation: Semin Roentgenol. 2001 Jul;36(3):250-60
references.pmid: 11475071
references.citation: Med Phys. 2002 May;29(5):755-70
references.pmid: 12033572
references.citation: Nucl Med Biol. 1996 Aug;23(6):717-35
references.pmid: 8940714
references.citation: Med Phys. 2007 Feb;34(2):689-702
references.pmid: 17388187
references.citation: Phys Med Biol. 1997 Dec;42(12):2463-80
references.pmid: 9434301
references.citation: Med Phys. 1994 Apr;21(4):529-38
references.pmid: 8058019
references.citation: Phys Med. 2006;21 Suppl 1:28-34
references.pmid: 17645990
references.citation: J Natl Cancer Inst. 2000 Jul 5;92(13):1081-7
references.pmid: 10880551
references.citation: J Nucl Med. 2001 Jan;42(1):9-16
references.pmid: 11197987
references.citation: Radiology. 1998 Nov;209(2):511-8
references.pmid: 9807581
references.citation: J Nucl Med. 2005 May;46(5):859-67
references.pmid: 15872361
references.citation: IEEE Trans Med Imaging. 2003 Sep;22(9):1100-10
references.pmid: 12956265
references.citation: J Nucl Med. 2002 Mar;43(3):325-9
references.pmid: 11884491
references.citation: Eur Radiol. 2003 Jul;13(7):1635-44
references.pmid: 12835979
references.citation: Radiology. 1991 Jun;179(3):765-70
references.pmid: 2027989
references.citation: IEEE Trans Med Imaging. 1994;13(4):601-9
references.pmid: 18218538
references.citation: Med Phys. 2000 Jul;27(7):1535-43
references.pmid: 10947256
references.citation: J Nucl Med. 2009 Sep;50(9):1401-8
references.pmid: 19690029
references.citation: J Nucl Med. 2000 Nov;41(11):1851-8
references.pmid: 11079494
references.citation: Ann Surg Oncol. 2007 Jan;14(1):3-13
references.pmid: 17066235
references.citation: Aust N Z J Surg. 2000 Mar;70(3):162-7
references.pmid: 10765896