Title: Evaluation of a Variable-Aperture Full-Ring SPECT System using Large-Area Pixelated CZT Modules: A Simulation Study for Brain SPECT Applications

Abstract

Single photon emission computed tomography (SPECT) scanner using cadmium zinc telluride (CZT) offers improved imaging capability over conventional NaI (Tl)-based SPECT scanner. We aim to demonstrate a full-ring SPECT system design with eight large-area CZT detectors that can be used for a broad spectrum of SPECT radiopharmaceuticals and provides higher sensitivity and better spatial resolution than those of conventional NaI (Tl)-based gamma cameras. A newly-designed full-ring SPECT system is composed of 8 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 were made between our design and a conventional SPECT scanner. The proposed scanner could result in up to about 3 times faster in acquisition time over conventionalmore » scan time at same acquisition time per step. The spatial resolution of our proposed scanner was similar or better to that of the conventional scanner, and there was significant performance improvement over the conventional scanner particularly in sensitivity (approximately 4 times). Overall, we successfully reconstructed the phantom image for both ⁹⁹mTc-based perfusion and ¹²³I-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 the 0.8 for the ¹²³I-based DaT study. In conclusion, we demonstrated the potential of our new full-ring CZT SPECT design, showing improved performance metrics such as improved system sensitivity and CNR while maintaining other important imaging parameters such as spatial resolution.« less

Authors:

Huh, Yoonsuk ^[1]; Yang, Jaewon ^[1]; Dim, Odera U. ^[2]; Cui, Yonggang ^[2]; Tao, Weijie ^[3]; Huang, Qiu ^[3]; Gullberg, Grant T. ^[4]; Seo, Youngho ^[4]

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+ Show Author Affiliations

1. Univ. of California, San Francisco, CA (United States)
2. Brookhaven National Lab. (BNL), Upton, NY (United States)
3. Shanghai Jiao Tong Univ. (China)
4. Univ. of California, San Francisco, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Publication Date:

Thu Mar 11 00:00:00 EST 2021

Research Org.:

Brookhaven National Lab. (BNL), Upton, NY (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA), Office of Nonproliferation and Verification Research and Development; National Inst. of Biomedical Imaging and Bioengineering; National Heart, Lung, and Blood Inst.

OSTI Identifier:

1770726

Report Number(s):

BNL-213700-2021-JAAM
Journal ID: ISSN 0094-2405

Grant/Contract Number:  

SC0012704; R01EB026331; R01EB012965; R01HL135490

Resource Type:

Accepted Manuscript

Journal Name:

Medical Physics

Additional Journal Information:

Journal Volume: 48; Journal Issue: 5; Journal ID: ISSN 0094-2405

Publisher:

American Association of Physicists in Medicine

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; SPECT; CZT detector; Full ring; Brain SPECT; Monte Carlo simulation