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Renner A, Rausch I, Cal Gonzalez J, Laistler E, Moser E, Jochimsen T, Sattler T, Sabri O, Beyer T, Figl M, Birkfellner W, Sattler B. Technical Note: A PET/MR coil with an integrated, orbiting 511 keV transmission source for PET/MR imaging validated in an animal study. Med Phys 2022; 49:2366-2372. [PMID: 35224747 PMCID: PMC9310742 DOI: 10.1002/mp.15586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 02/04/2022] [Accepted: 02/04/2022] [Indexed: 11/11/2022] Open
Abstract
Background Purpose Methods Results Conclusion
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Affiliation(s)
- Andreas Renner
- Center for Medical Physics and Biomedical Engineering Medical University Vienna Austria
- Department of Radiation Oncology Medical University Vienna Austria
| | - Ivo Rausch
- Center for Medical Physics and Biomedical Engineering Medical University Vienna Austria
| | - Jacobo Cal Gonzalez
- Center for Medical Physics and Biomedical Engineering Medical University Vienna Austria
| | - Elmar Laistler
- Center for Medical Physics and Biomedical Engineering Medical University Vienna Austria
| | - Ewald Moser
- Center for Medical Physics and Biomedical Engineering Medical University Vienna Austria
| | - Thies Jochimsen
- Department of Nuclear Medicine University Hospital Leipzig Germany
| | - Tatjana Sattler
- Clinic for Ruminants and Swine University of Leipzig Germany
| | - Osama Sabri
- Department of Nuclear Medicine University Hospital Leipzig Germany
| | - Thomas Beyer
- Center for Medical Physics and Biomedical Engineering Medical University Vienna Austria
| | - Michael Figl
- Center for Medical Physics and Biomedical Engineering Medical University Vienna Austria
| | - Wolfgang Birkfellner
- Center for Medical Physics and Biomedical Engineering Medical University Vienna Austria
| | - Bernhard Sattler
- Department of Nuclear Medicine University Hospital Leipzig Germany
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Kwon SI, Ota R, Berg E, Hashimoto F, Nakajima K, Ogawa I, Tamagawa Y, Omura T, Hasegawa T, Cherry SR. Ultrafast timing enables reconstruction-free positron emission imaging. NATURE PHOTONICS 2021; 15:914-918. [PMID: 35663419 PMCID: PMC9165659 DOI: 10.1038/s41566-021-00871-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 08/04/2021] [Indexed: 05/07/2023]
Abstract
X-ray and gamma-ray photons are widely used for imaging but require a mathematical reconstruction step, known as tomography, to produce cross-sectional images from the measured data. Theoretically, the back-to-back annihilation photons produced by positron-electron annihilation can be directly localized in three-dimensional space using time-of-flight information without tomographic reconstruction. However, this has not yet been demonstrated due to the insufficient timing performance of available radiation detectors. Here, we develop techniques based on detecting prompt Cerenkov photons, which when combined with a convolutional neural network for timing estimation resulted in an average timing precision of 32 picoseconds, corresponding to a spatial precision of 4.8 mm. We show this is sufficient to produce cross-sectional images of a positron-emitting radionuclide directly from the detected coincident annihilation photons, without using any tomographic reconstruction algorithm. The reconstruction-free imaging demonstrated here directly localizes positron emission, and frees the design of an imaging system from the geometric and sampling constraints that normally present for tomographic reconstruction.
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Affiliation(s)
- Sun Il Kwon
- Department of Biomedical Engineering, University of California; Davis, USA
| | - Ryosuke Ota
- Central Research Laboratory, Hamamatsu Photonics K.K.; Hamamatsu, Japan
| | - Eric Berg
- Department of Biomedical Engineering, University of California; Davis, USA
| | - Fumio Hashimoto
- Central Research Laboratory, Hamamatsu Photonics K.K.; Hamamatsu, Japan
| | | | - Izumi Ogawa
- Faculty of Engineering, University of Fukui; Fukui, Japan
| | | | - Tomohide Omura
- Central Research Laboratory, Hamamatsu Photonics K.K.; Hamamatsu, Japan
| | - Tomoyuki Hasegawa
- School of Allied Health Sciences, Kitasato University; Kitasato, Japan
| | - Simon R. Cherry
- Department of Biomedical Engineering, University of California; Davis, USA
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Zeng T, Gao J, Gao D, Kuang Z, Sang Z, Wang X, Hu L, Chen Q, Chu X, Liang D, Liu X, Yang Y, Zheng H, Hu Z. A GPU-accelerated fully 3D OSEM image reconstruction for a high-resolution small animal PET scanner using dual-ended readout detectors. ACTA ACUST UNITED AC 2020; 65:245007. [DOI: 10.1088/1361-6560/aba6f9] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Saeed M, El Khoukhi T, Boulaich Y, Chakir E, Maged M, Boukhal H, El Bardouni T. Positron-based attenuation correction for Positron Emission Tomography data using MCNP6 code. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2019. [DOI: 10.1016/j.jrras.2015.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- M. Saeed
- Radiations and Nuclear Systems Laboratory, Abdelmalek Essaâdi University, Faculty of Sciences, Tetouan, Morocco
| | | | | | - E. Chakir
- LHESIR, Faculty of sciences, Ibn Tofail University, Kenitra, Morocco
| | - M. Maged
- LHESIR, Faculty of sciences, Ibn Tofail University, Kenitra, Morocco
| | - H. Boukhal
- Radiations and Nuclear Systems Laboratory, Abdelmalek Essaâdi University, Faculty of Sciences, Tetouan, Morocco
| | - T. El Bardouni
- Radiations and Nuclear Systems Laboratory, Abdelmalek Essaâdi University, Faculty of Sciences, Tetouan, Morocco
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137Cs transmission imaging and segmented attenuation corrections in a small animal PET scanner. Radiol Phys Technol 2017; 10:321-330. [DOI: 10.1007/s12194-017-0407-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 07/01/2017] [Accepted: 07/03/2017] [Indexed: 10/19/2022]
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Utility of respiratory-gated small-animal PET/CT in the chronologic evaluation of an orthotopic lung cancer transplantation mouse model. Radiol Phys Technol 2015; 8:266-77. [PMID: 25921487 DOI: 10.1007/s12194-015-0316-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 04/16/2015] [Accepted: 04/20/2015] [Indexed: 01/07/2023]
Abstract
Our aim in this study was to clarify the effects of respiratory-gated PET in the evaluation of lung cancer according to the (18)F-FDG uptake in an orthotopic transplantation mouse model. We created such a model, and we performed PET/CT. The mice were divided into two groups according to tumor volume: a small-tumor group (<20 mm(3)) and a large-tumor group (>20 mm(3)). We reconstructed the following conditions based on list-mode data: non-gated (3D) images and gated (4D) images, divided based on the respiratory cycle (expiration phase, stable phase, and inspiration phase). We calculated the maximum standardized uptake values (SUVmax) in each phase. We used the % difference [= (4D SUVmax - 3D SUVmax)/3D PET SUVmax × 100 (%)] to evaluate the differences in the 4D SUVmax and 3D SUVmax. The 4D SUVmax values were significantly higher than the 3D SUVmax, regardless of the tumor size. The % difference for the small tumors was greater than that for the large tumors, and it was highest in the stable phase. We conclude that the SUVmax in the stable phase under respiratory-gated PET are the most reliable. The SUVmax observed under non-gated PET are considered to be more frequently underestimated in cases involving small tumors than in those involving large tumors. In the chronologic study evaluating the time course of tumor development, the size of the tumor is small in early stage, and respiratory-gated PET is effective in reducing the underestimation of such tumors caused by respiratory motion.
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Hypoxia in head and neck cancer in theory and practice: a PET-based imaging approach. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2014; 2014:624642. [PMID: 25214887 PMCID: PMC4158154 DOI: 10.1155/2014/624642] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 08/06/2014] [Indexed: 11/24/2022]
Abstract
Hypoxia plays an important role in tumour recurrence among head and neck cancer patients. The identification and quantification of hypoxic regions are therefore an essential aspect of disease management. Several predictive assays for tumour oxygenation status have been developed in the past with varying degrees of success. To date, functional imaging techniques employing positron emission tomography (PET) have been shown to be an important tool for both pretreatment assessment and tumour response evaluation during therapy. Hypoxia-specific PET markers have been implemented in several clinics to quantify hypoxic tumour subvolumes for dose painting and personalized treatment planning and delivery. Several new radiotracers are under investigation. PET-derived functional parameters and tracer pharmacokinetics serve as valuable input data for computational models aiming at simulating or interpreting PET acquired data, for the purposes of input into treatment planning or radio/chemotherapy response prediction programs. The present paper aims to cover the current status of hypoxia imaging in head and neck cancer together with the justification for the need and the role of computer models based on PET parameters in understanding patient-specific tumour behaviour.
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Gammon ST, Foje N, Brewer EM, Owers E, Downs CA, Budde MD, Leevy WM, Helms MN. Preclinical anatomical, molecular, and functional imaging of the lung with multiple modalities. Am J Physiol Lung Cell Mol Physiol 2014; 306:L897-914. [DOI: 10.1152/ajplung.00007.2014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In vivo imaging is an important tool for preclinical studies of lung function and disease. The widespread availability of multimodal animal imaging systems and the rapid rate of diagnostic contrast agent development have empowered researchers to noninvasively study lung function and pulmonary disorders. Investigators can identify, track, and quantify biological processes over time. In this review, we highlight the fundamental principles of bioluminescence, fluorescence, planar X-ray, X-ray computed tomography, magnetic resonance imaging, and nuclear imaging modalities (such as positron emission tomography and single photon emission computed tomography) that have been successfully employed for the study of lung function and pulmonary disorders in a preclinical setting. The major principles, benefits, and applications of each imaging modality and technology are reviewed. Limitations and the future prospective of multimodal imaging in pulmonary physiology are also discussed. In vivo imaging bridges molecular biological studies, drug design and discovery, and the imaging field with modern medical practice, and, as such, will continue to be a mainstay in biomedical research.
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Affiliation(s)
- Seth T. Gammon
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Nathan Foje
- Department of Biological Sciences, Notre Dame Integrated Imaging Facility, Notre Dame, Indiana
| | - Elizabeth M. Brewer
- Department of Pediatrics Center for Cystic Fibrosis and Airways Disease Research, Emory University, Atlanta, Georgia
| | - Elizabeth Owers
- Department of Biological Sciences, Notre Dame Integrated Imaging Facility, Notre Dame, Indiana
| | - Charles A. Downs
- Nell Hodgson Woodruff School of Nursing, Emory University, Atlanta, Georgia; and
| | - Matthew D. Budde
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - W. Matthew Leevy
- Department of Biological Sciences, Notre Dame Integrated Imaging Facility, Notre Dame, Indiana
| | - My N. Helms
- Department of Pediatrics Center for Cystic Fibrosis and Airways Disease Research, Emory University, Atlanta, Georgia
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Lajtos I, Czernin J, Dahlbom M, Daver F, Emri M, Farshchi-Heydari S, Forgacs A, Hoh CK, Joszai I, Krizsan AK, Lantos J, Major P, Molnar J, Opposits G, Tron L, Vera DR, Balkay L. Cold wall effect eliminating method to determine the contrast recovery coefficient for small animal PET scanners using the NEMA NU-4 image quality phantom. Phys Med Biol 2014; 59:2727-46. [PMID: 24800813 DOI: 10.1088/0031-9155/59/11/2727] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The contrast recovery coefficients (CRC) were evaluated for five different small animal PET scanners: GE Explore Vista, Genisys4, MiniPET-2, nanoScan PC and Siemens Inveon. The NEMA NU-4 2008 performance test with the suggested image quality phantom (NU4IQ) does not allow the determination of the CRC values for the hot regions in the phantom. This drawback of NU4IQ phantom motivated us to develop a new method for this purpose. The method includes special acquisition and reconstruction protocols using the original phantom, and results in an artificially merged image enabling the evaluation of CRC values. An advantageous feature of this method is that it stops the cold wall effect from distorting the CRC calculation. Our suggested protocol results in a set of CRC values contributing to the characterization of small animal PET scanners. GATE simulations were also performed to validate the new method and verify the evaluated CRC values. We also demonstrated that the numerical values of this parameter depend on the actual object contrast of the hot region(s) and this mainly comes from the spillover effect. This effect was also studied while analysing the background activity level around the hot rods. We revealed that the calculated background mean values depended on the target contrast in a scanner specific manner. Performing the artificially merged imaging procedure and additional simulations using the micro hollow sphere (MHS) phantom geometry, we also proved that the inactive wall around the hot spheres can have a remarkable impact on the calculated CRC. In conclusion, we have shown that the proposed artificial merging procedure and the commonly used NU4IQ phantom prescribed by the NEMA NU-4 can easily deliver reliable CRC data otherwise unavailable for the NU4IQ phantom in the conventional protocol or the MHS phantom.
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Affiliation(s)
- Imre Lajtos
- Department of Nuclear Medicine, Medical Center, University of Debrecen, 4032 Debrecen, Nagyerdei krt. 98, Hungary
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