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Huh Y, Caravaca J, Kim J, Cui Y, Huang Q, Gullberg G, Seo Y. Simulation studies of a full-ring, CZT SPECT system for whole-body imaging of 99m Tc and 177 Lu. Med Phys 2023; 50:3726-3737. [PMID: 36916755 PMCID: PMC10503418 DOI: 10.1002/mp.16360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/26/2023] [Accepted: 02/26/2023] [Indexed: 03/15/2023] Open
Abstract
BACKGROUND Single photon emission computed tomography (SPECT) is an imaging modality that has demonstrated its utility in a number of clinical indications. Despite this progress, a high sensitivity, high spatial resolution, multi-tracer SPECT with a large field of view suitable for whole-body imaging of a broad range of radiotracers for theranostics is not available. PURPOSE With the goal of filling this technological gap, we have designed a cadmium zinc telluride (CZT) full-ring SPECT scanner instrumented with a broad-energy tungsten collimator. The final purpose is to provide a multi-tracer solution for brain and whole-body imaging. Our static SPECT does not rely on the dual- and the triple-head rotational SPECT standard paradigm, enabling a larger effective area in each scan to increase the sensitivity. We provide a demonstration of the performance of our design using a realistic model of our detector with simulated body-sized phantoms filled with 99m Tc and 177 Lu. METHODS We create a realistic model of our detector by using a combination of a Geant4 Application for Tomographic Emission (GATE) Monte Carlo simulation and a finite element model for the CZT response, accounting for low-energy tail effects in CZT that affects the sensitivity and the scatter correction. We implement a modified dual-energy-window scatter correction adapted for CZT. Other corrections for attenuation, detector and collimator response, and detector gaps and edges are also included. The images are reconstructed using the maximum-likelihood expectation-maximization. Detector and reconstruction performance are characterized with point sources, Derenzo phantoms, and a body-sized National Electrical Manufacturers Association (NEMA) Image Quality (IQ) phantom for both 99m Tc and 177 Lu. RESULTS Our SPECT design can resolve 7.9 mm rods for 99m Tc (140 keV) and 9.5 mm for 177 Lu (208 keV) in a hot-rod Derenzo phantom with a 3-min exposure and reach an image contrast of 78% for 99m Tc and 57% for 177 Lu using the NEMA IQ phantom with a 6-min exposure. Our modified scatter correction shows an improved contrast-recovery ratio compared to a standard correction. CONCLUSIONS In this paper, we demonstrate the good performance of our design for whole-body imaging purposes. This adds to our previous demonstration of improved qualitative and quantitative 99m Tc imaging of brain perfusion and 123 I imaging of dopamine transport with respect to state-of-the-art NaI dual-head cameras. We show that our design provides similar IQ and contrast to the commercial full-ring SPECT VERITON for 99m Tc. Regarding 177 Lu imaging of the 208 keV emissions, our design provides similar contrast to that of other state-of-the-art SPECTs with a significant reduction in exposure. The high sensitivity and extended energy range up to 250 keV makes our SPECT design a promising alternative for clinical imaging and theranostics of emerging radionuclides.
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Affiliation(s)
- Yoonsuk Huh
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA
| | - Javier Caravaca
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA
| | - Jaehyuk Kim
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Yonggang Cui
- Department of Nonproliferation and National Security, Brookhaven National Laboratory, Upton, New York, USA
| | - Qiu Huang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Grant Gullberg
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Youngho Seo
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Joint Graduate Group in Bioengineering, University of California, San Francisco, Berkeley, California, USA
- Department of Nuclear Engineering, University of California, Berkeley, California, USA
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Huh Y, Yang J, Dim OU, Cui Y, Tao W, Huang Q, Gullberg GT, Seo Y. Evaluation of a variable-aperture full-ring SPECT system using large-area pixelated CZT modules: A simulation study for brain SPECT applications. Med Phys 2021; 48:2301-2314. [PMID: 33704793 DOI: 10.1002/mp.14836] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 01/28/2021] [Accepted: 03/03/2021] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Single photon emission computed tomography (SPECT) scanners using cadmium zinc telluride (CZT) offer compact, lightweight, and improved imaging capability over conventional NaI(Tl)-based SPECT scanners. The main purpose in this study is to propose a full-ring SPECT system design with eight large-area CZT detectors that can be used for a broad spectrum of SPECT radiopharmaceuticals and demonstrate the performance of our system in comparison to the reference conventional NaI(Tl)-based two-head Anger cameras. METHODS A newly designed full-ring SPECT system is composed of eight large-area CZT cameras (128 mm × 179.2 mm effective area) that can be independently swiveled around their own axes of rotation independently and can have radial motion for varying aperture sizes that can be adapted to different sizes of imaging volume. Extended projection data were generated by conjoining projections of two adjacent detectors to overcome the limited field-of-view (FOV) by each CZT camera. Using Monte Carlo simulations, we evaluated this new system design with digital phantoms including a Derenzo hot rod phantom and a Zubal brain phantom. Comparison of performance metrics such as spatial resolution, sensitivity, contrast-to-noise ratio (CNR), and contrast-recovery ratio was made between our design and conventional SPECT scanners having different pixel sizes and radii of rotation (one clinically well-known type and two arbitrary types matched to our proposed CZT-SPECT geometries). RESULTS The proposed scanner could result in up to about three times faster in acquisition time over conventional scan time at same acquisition time per step. The spatial resolution improvement, or deterioration, of our proposed scanner compared to the clinical-type scanner was dependent upon the location of the point source. However, there were overall performance improvements over the three different setups of the conventional scanner particularly in volume sensitivity (approximately up to 1.7 times). Overall, we successfully reconstructed the phantom image for both 99m Tc-based perfusion and 123 I-based dopamine transporter (DaT) brain studies simulated for our new design. In particular, the striatal/background contrast-recovery ratio in 3-to-1 reference ratio was over 0.8 for the 123 I-based DaT study. CONCLUSIONS We proposed a variable-aperture full-ring SPECT system using combined pixelated CZT and energy-optimized parallel-hole collimator modules and evaluated the performance of this scanner using relevant digital phantoms and MC simulations. Our studies demonstrated the potential of our new full-ring CZT-SPECT design, showing reduced acquisition time and improved sensitivity with acceptable CNR and spatial resolution.
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Affiliation(s)
- Yoonsuk Huh
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - Jaewon Yang
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - Odera U Dim
- Department of Nonproliferation and National Security, Brookhaven National Laboratory, Upton, NY, USA
| | - Yonggang Cui
- Department of Nonproliferation and National Security, Brookhaven National Laboratory, Upton, NY, USA
| | - Weijie Tao
- Department of Nuclear Medicine, Ruijin Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Qiu Huang
- Department of Nuclear Medicine, Ruijin Hospital, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Grant T Gullberg
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Youngho Seo
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA.,Department of Radiation Oncology, University of California, San Francisco, CA, USA.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,Joint Graduate Group in Bioengineering, University of California, San Francisco, CA, USA.,Department of Nuclear Engineering, University of California, Berkeley, CA, USA
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Lavrentyev AA, Gabrelian BV, Vu TV, Shkumat PN, Fochuk PM, Parasyuk OV, Kityk IV, Luzhnyi IV, Khyzhun OY, Piasecki M. Manifestation of Anomalous Weak Space-Charge-Density Acentricity for a Tl4HgBr6 Single Crystal. Inorg Chem 2016; 55:10547-10557. [DOI: 10.1021/acs.inorgchem.6b01389] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anatoliy A. Lavrentyev
- Department of Electrical Engineering and
Electronics, Don State Technical University, Gagarin Sq. 1, 344010 Rostov-on-Don, Russian Federation
| | - Boris V. Gabrelian
- Department of Electrical Engineering and
Electronics, Don State Technical University, Gagarin Sq. 1, 344010 Rostov-on-Don, Russian Federation
| | - Tuan V. Vu
- Department of Electrical Engineering and
Electronics, Don State Technical University, Gagarin Sq. 1, 344010 Rostov-on-Don, Russian Federation
| | - Peter N. Shkumat
- Department of Electrical Engineering and
Electronics, Don State Technical University, Gagarin Sq. 1, 344010 Rostov-on-Don, Russian Federation
| | - Petro M. Fochuk
- Yuriy Fedkovych Chernivtsi National University, 2 Kotziubynskoho Street, UA-58012 Chernivtsi, Ukraine
| | - Oleg V. Parasyuk
- Department of Solid State Physics, Lesya Ukrainka Eastern European National University, 13 Voli Avenue, UA-4025 Lutsk, Ukraine
| | - Iwan V. Kityk
- Faculty of Electrical Engineering, Częstochowa University of Technology, Armii Krajowej 17, PL-42-217 Częstochowa, Poland
| | - Ivan V. Luzhnyi
- Frantsevych
Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, 3 Krzhyzhanivsky Street, UA-03142 Kyiv, Ukraine
| | - Oleg Y. Khyzhun
- Frantsevych
Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, 3 Krzhyzhanivsky Street, UA-03142 Kyiv, Ukraine
| | - Michal Piasecki
- Institute
of Physics, J. Dlugosz University of Częstochowa, Armii Krajowej 13/15, PL-42-200 Częstochowa, Poland
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