Article
Engineering, Biomedical
Mitsuo Watanabe, Takahiro Moriya, Hiroshi Uchida, Tomohide Omura
Summary: The study evaluates the potential of a multilayer depth-of-interaction positron emission tomography (DOI-PET) detector as a time-of-flight (TOF) detector by investigating the coincidence time resolution (CTR) using various scintillator structures and timing detection methods.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Review
Engineering, Biomedical
Dennis R. Schaart
Summary: The review discusses the impressive evolution of imaging performance in clinical PET systems over the past years, focusing on the optimization of TOF detectors. It emphasizes the importance of timing performance optimization in maximizing the value of PET systems, especially in personalized medicine.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Engineering, Biomedical
Eiji Yoshida, Fujino Obata, Kei Kamada, Akira Yoshikawa, Taiga Yamaya
Summary: A CLS PET detector was developed for TOF-DOI brain PET system using fast LGSO crystal, providing improved energy resolution, DOI resolution, and CRT compared to previous designs. The detector showed significantly higher coincidence sensitivity, better energy resolution, and improved time resolution.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Radiology, Nuclear Medicine & Medical Imaging
Eiji Yoshida, Fujino Obata, Kei Kamada, Taiga Yamaya
Summary: In order to improve the image quality of positron emission tomography (PET), DOI and TOF information are crucial. A DOI-TOF detector was developed based on a single-ended readout scheme with a continuous layered GFAG array, aiming to enhance crystal response and achieve better DOI resolution, energy resolution, and timing resolution. Performance comparison showed significant improvements over detectors with three discrete layers.
IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES
(2021)
Article
Engineering, Biomedical
Han Gyu Kang, Hideaki Tashima, Fumihiko Nishikido, Go Akamatsu, Hidekazu Wakizaka, Makoto Higuchi, Taiga Yamaya
Summary: A mouse brain PET prototype was successfully developed with a staggered 3-layer DOI detector, achieving clear identification of brain structures with high contrast. The use of DOI detector improved resolution and reduced inter-crystal scatter, resulting in good imaging performance.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Engineering, Biomedical
Jens Maebe, Stefaan Vandenberghe
Summary: In this study, the use of 3D convolutional neural networks for gamma arrival time estimation in monolithic scintillation detectors was investigated. The results showed that better coincidence time resolution and improved detector uniformity could be achieved with the proposed method.
PHYSICS IN MEDICINE AND BIOLOGY
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Eiji Yoshida, Han Gyu Kang, Fujino Obata, Taiga Yamaya
Summary: The relationship between crystal surface treatment and detector performance was investigated, and it was found that one-sided saw-cut crystals showed the best time resolution and achieved a depth resolution of about 5 mm. In comparison, two-sided saw-cut crystals had poorer time resolution and equivalent depth resolution to one-sided saw-cut crystals, while mechanical polished crystals had the best time resolution but the worst depth resolution. The best balance was observed in the array of one-sided saw-cut crystals.
IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
M. Amin Choghadi, Sheng C. Huang, Kenji Shimazoe, Hiroyuki Takahashi
Summary: This study experimentally examined the DOI resolution of four Ce:GAGG crystals with different surface treatments. Results indicated that there is an optimal surface roughness for the best performance of the crystals, with further increase in roughness degrading the DOI resolution.
Article
Engineering, Biomedical
Jens Maebe, Stefaan Vandenberghe
Summary: This study investigates how different surface finishes affect the photon collection efficiency and timing performance in monolithic BGO detectors based on Cerenkov light. Results show that substituting a polished back surface with a rough surface improves the collection efficiency of high incidence angle Cerenkov photons, leading to an overall increase in photon collection efficiency by 34%. This improvement in photon collection efficiency results in a better coincidence time resolution with an 18% reduction in full width at tenth maximum.
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Review
Crystallography
Xin Yu, Xi Zhang, Heng Zhang, Hao Peng, Qiushi Ren, Jianfeng Xu, Qiyu Peng, Siwei Xie
Summary: Positron emission tomography (PET) is widely used for the diagnosis of tumors, cardiovascular diseases, and neurological diseases. This article introduces the principle and requirements of scintillation crystals in PET and analyzes the performance of different crystals. LYSO is currently the best-performing crystal, while LaBr3 has better timing characteristics and light output. GAGG detectors have a high depth of interaction resolution and great potential for applications.
Article
Instruments & Instrumentation
Fumihiko Nishikido, Takayuki Obata, Mikio Suga, Yuma Iwao, Hideaki Tashima, Eiji Yoshida, Md Shahadat Hossain Akram, Taiga Yamaya
Summary: We developed a scalable add-on PET prototype based on 4-layered depth-of-interaction (DOI) detectors for simultaneous PET/MRI measurements. The prototype demonstrated high spatial and energy resolutions, with no degradation of PET performance caused by MRI measurements. This prototype has the potential for clinical diagnosis and research applications.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2022)
Article
Multidisciplinary Sciences
Philip Krause, Edith Rogers, Muhammad Danang Birowosuto, Qibing Pei, Etiennette Auffray, Andrey N. Vasil'ev, Gregory Bizarri
Summary: Despite the clinical acceptance of ToF-PET, there is still a gap between the technology's performance and the end-user's needs. The concept of heterostructured detectors has been proposed to bypass the current performance limitations. Based on Monte Carlo simulations, a survey of heterostructure performance versus detector design is presented, enabling the establishment of design rules for the development of improved detectors.
Article
Instruments & Instrumentation
Fumihiko Nishikido, Takayuki Obata, Mikio Suga, Yuma Iwao, Hideaki Tashima, Eiji Yoshida, Md Shahadat Hossain Akram, Taiga Yamaya
Summary: A new PET add-on prototype was developed with high sensitivity and improved spatial resolution by integrating DOI detectors and a birdcage RF coil.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2022)
Article
Instruments & Instrumentation
Akram Mohammadi, Fumihiko Nishikido, Naoko Inadama, Toshiaki Sakai, Taiga Yamaya
Summary: This article introduces a four-layer scintillation detector based on depth-of-interaction (DOI) and subsurface laser engraving (SSLE) technologies. Compared to traditional orderly crystals, this detector is easier to manufacture and has comparable performance.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2023)
Article
Engineering, Biomedical
F. P. Schmidt, J. C. Kraemer, C. Parl, M. Schmand, B. J. Pichler
Summary: The C13500 series TOF-PET detector modules are a promising choice for PET system development due to their all-in-one solution and modularity. However, the modules currently available are designed for clinical whole-body PET systems and cannot support smaller scintillation crystals. In this study, we developed a PET detector based on TOF-PET modules using a light sharing approach and smaller LSO scintillation crystals, achieving high resolution and energy detection capabilities.
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Heying Duan, Lucia Baratto, Negin Hatami, Tie Liang, Craig S. Levin, Mohammad Mehdi Khalighi, Andrei Iagaru
Summary: The study evaluates the effect of different reduced PET acquisition times in patients with prostate cancer who underwent Ga-68-PSMA-11 or (68)GaRM2 PET/MRI. Results suggest that routine 3-minute acquisitions provide similar results to 4-minute acquisitions, while 2-minute acquisitions provide acceptable performance.
AMERICAN JOURNAL OF ROENTGENOLOGY
(2022)
Article
Physics, Multidisciplinary
Andrea Gonzalez-Montoro, Shirin Pourashraf, Joshua W. Cates, Craig S. Levin
Summary: This study aims to develop a scalable detector element with excellent coincidence time resolution (CTR) for TOF-PET using BGO scintillators. The CTR performance of BGO crystal elements of various lengths was evaluated using advanced post-processing methods.
FRONTIERS IN PHYSICS
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Li Tao, Yihui He, Mercouri G. Kanatzidis, Craig S. Levin
Summary: In this study, the prompt photon emission and timing capability of two new perovskite semiconductor materials, CsPbCl3 and CsPbBr3, were investigated. Their performance was compared with TlBr, another semiconductor material. The results showed that CsPbCl3 and CsPbBr3 exhibited good coincidence time resolution (CTR) performance, suggesting that these new materials could be excellent candidates as PET detector materials.
IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Muhammad Nasir Ullah, Craig S. Levin
Article
Instruments & Instrumentation
A. Gonzalez-Montoro, S. Pourashraf, M. S. Lee, J. W. Cates, C. S. Levin
Summary: The goal of this work is to develop a TOF-PET detector system with 100 ps CTR using 20 mm scintillator crystal elements. The proposed system could provide a 1.5-fold better image SNR compared to current clinical TOF-PET systems. The system configuration includes LGSO scintillation crystal elements coupled to SiPMs and readout by a fast, high precision IC. Results achieved using the IC board demonstrate the potential of a scalable IC readout solution for a 100 ps CTR TOF-PET design.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2023)
Article
Neuroimaging
Sanaz Nazari-Farsani, Yannan Yu, Rui Duarte Armindo, Maarten Lansberg, David S. Liebeskind, Gregory Albers, Soren Christensen, Craig S. Levin, Greg Zaharchuk
Summary: A deep convolutional neural network (DCNN) model trained with diffusion-weighted imaging obtained at admission was able to predict the final infarct volume and location in acute stroke patients 3-7 days after stroke onset. The prediction accuracy of the model was comparable to models that consider both diffusion-weighted imaging and perfusion-weighted imaging. This finding may help to reduce the time required for stroke imaging.
NEUROIMAGE-CLINICAL
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Qian Dong, Zander Adams, Ronald D. Watkins, Brian J. Lee, Chen-Ming Chang, Ilaria Sacco, Craig S. Levin
Summary: This paper reports the MR-compatibility study results of two fully assembled second-generation PET insert detector modules. The results show that the operation of PET detectors does not induce any significant artifacts in MR images. The presence of operating TOF-PET detectors leads to a slight degradation in MR image signal-to-noise ratio and relative homogeneity, but the degradation is within an acceptable range. The PET detector performance and time-of-flight (TOF) capability are preserved under different tested MR conditions, except for a slight difference in energy resolution in the EPI sequence.
Article
Engineering, Biomedical
Qian Dong, Zander Adams, Ronald D. Watkins, Chen-Ming Chang, Brian J. Lee, Craig S. Levin
Summary: This study evaluates the radiofrequency (RF) shielding effectiveness, gradient-induced eddy current, magnetic resonance (MR) susceptibility, and positron emission tomography (PET) photon attenuation of six shielding materials. The materials were tested in benchtop experiments and in a 3T MR scanner. The results show the overall performance of the conductive coating as a high-performance Faraday cage material for PET/MRI applications.
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Article
Engineering, Biomedical
Qian Dong, Chen-Ming Chang, Brian J. Lee, Ilaria Sacco, Salar Sajedi, Zander Adams, Peter Fischer, Craig S. Levin
Summary: Objective: Developing a portable RF-penetrable TOF-PET insert for simultaneous PET/MRI. Approach: Evaluating PET performance of two detector modules outside the MR room. Main results: Demonstrating excellent TOF capability and stability for scaling up to a full ring comprising 16 detector modules.
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Qian Dong, Ilaria Sacco, Chen-Ming Chang, Craig S. Levin
Summary: This article presents the front-end detector readout electronics designed for PET/MRI's RF-timing PET insert. Experimental results show that the front-end design achieves excellent coincidence time and energy resolution, and demonstrates the capability to handle high-count rate applications. These results indicate that this front-end design is feasible for high-sensitivity TOF PET applications.
IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Md Shahadat Hossain Akram, Craig S. Levin, Fumihiko Nishikido, Sodai Takyu, Takayuki Obata, Taiga Yamaya
Summary: The purpose of this study is to evaluate the RF field responses of partial-ring RF-shielded oval-shaped PET inserts used in combination with an MRI body RF coil. The study found that the detector openings in the first and third quadrants of the inserts had higher field penetration, and compared to the MRI-only case, there were significant reductions in RF homogeneity, flip angle, and SNR for these openings.
RADIOLOGICAL PHYSICS AND TECHNOLOGY
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Riley Stanford-Hill, Andrew Groll, Craig S. Levin
Summary: This study focuses on a high-resolution CZT PET system and combines GATE simulations with charge transport and electronics modeling to provide a deeper understanding and analysis of the system. The results show that the simulation achieves coincidence timing and energy resolution similar to experimental data.
Article
Radiology, Nuclear Medicine & Medical Imaging
Md Shahadat Hossain Akram, Fumihiko Nishikido, Craig S. Levin, Sodai Takyu, Takayuki Obata, Taiga Yamaya
Summary: The purpose of this study is to investigate the MRI compatibility of an RF field-penetrable oval-shaped PET insert that incorporates an MRI built-in body RF coil. The results show that the B1 maps of the oval insert were similar to those of the MRI-only case, but there were significant reductions in the signal-to-noise ratios (SNRs) of the spin echo, gradient echo, and echo planar images. Additionally, larger RF pulse amplitudes were required for the oval insert, and there was a 30% decrease in the average RF reception sensitivity.
JAPANESE JOURNAL OF RADIOLOGY
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Diana Jeong, Li Tao, Xin Ran Song, Zander Adams, Xin Zhang, Jinghui Wang, Craig S. Levin
Summary: In order to improve the time-of-flight PET image quality, it is essential to enhance the annihilation photon pair coincidence time resolution. Recent studies suggest that direct detection of ionization tracks can significantly improve the timing resolution. By simulating different materials and charge carrier dynamics, it is possible to optimize the experimental platform for detecting single photon interactions more precisely.
Article
Physics, Multidisciplinary
C. S. Levin
Summary: This paper discusses the design considerations and promising detector technologies for time-of-flight positron emission tomography (TOF-PET). TOF-PET improves the signal-to-noise ratio of reconstructed images, leading to better disease visualization and quantification, lower injected dose, and/or shorter study duration. The coincidence time resolution of the detector system determines the degree of signal-to-noise ratio improvement. Various research and development efforts have been focused on enhancing coincidence time resolution without compromising detection efficiency. The paper also introduces a non-scintillation-based detection concept that could achieve ultrahigh coincidence time resolution.
ACTA PHYSICA POLONICA A
(2022)