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Cited by 206Medical Imaging Techniques and ApplicationsRadiation Dose and ImagingCardiac Imaging and Diagnostics

Improvement in PET/CT Image Quality with a Combination of Point-Spread Function and Time-of-Flight in Relation to Reconstruction Parameters

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Akamatsu, Go, Ishikawa, Kaori, Mitsumoto, Katsuhiko, Taniguchi, Takafumi, Ohya, Nobuyoshi, Baba, Shingo, Abe, Koichiro, Sasaki, Masayuki·2012·Journal of Nuclear Medicine
DOI 10.2967/jnumed.112.103861
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Abstract

UNLABELLED: The aim of this study was to investigate the effects of the point-spread function (PSF) and time-of-flight (TOF) on improving (18)F-FDG PET/CT images in relation to reconstruction parameters and noise-equivalent counts (NEC). METHODS: This study consisted of a phantom study and a retrospective analysis of 39 consecutive patients who underwent clinical (18)F-FDG PET/CT. The body phantom of the National Electrical Manufacturers Association and International Electrotechnical Commission with a 10-mm-diameter sphere was filled with an (18)F-FDG solution with a 4:1 radioactivity ratio compared with the background. The PET data were reconstructed with the baseline ordered-subsets expectation maximization (OSEM) algorithm, with the OSEM+PSF model, with the OSEM+TOF model, and with the OSEM+PSF+TOF model. We evaluated image quality by visual assessment, the signal-to-noise ratio of the 10-mm sphere (SNR(10 mm)), the contrast of the 10-mm sphere, and the coefficient of variance in the phantom study and then determined the optimal reconstruction parameters. We also examined the effects of PSF and TOF on the quality of clinical images using the signal-to-noise ratio in the liver (SNR(liver)) in relation to the NEC in the liver (NEC(liver)). RESULTS: In the phantom study, the SNR(10 mm) was the highest for the OSEM+PSF+TOF model, and the highest value was obtained at iteration 2 for algorithms with the TOF and at iteration 3 for those without the TOF. In terms of a postsmoothing filter full width at half maximum (FWHM), the high SNR(10 mm) was obtained with no filtering or was smaller than 2 mm for algorithms with PSF and was 4-6 mm for those without PSF. The balance between the contrast recovery and noise is different for algorithms with either PSF or TOF. A combination of PSF and TOF improved SNR(10 mm), contrast, and coefficient of variance, especially with a small-FWHM gaussian filter. In the clinical study, the SNR(liver) of the low-NEC(liver) group in the OSEM+PSF+TOF model was compared with that of the high-NEC(liver) group in conventional OSEM. The PSF+TOF improved the SNR(liver) by about 24.9% ± 9.81%. CONCLUSION: A combination of PSF and TOF clearly improves image quality, whereas optimization of the reconstruction parameters is necessary to obtain the best performance for PSF or TOF. Furthermore, this combination has the potential to provide good image quality with either lower activity or shorter acquisition time, thus improving patient comfort and reducing the radiation burden.

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  • Compared to standard OSEM reconstruction, OSEM with TOF shows improved noise characteristics.

    “Compared to standard ordered subset expectation maximization (OSEM) reconstruction, OSEM with TOF shows improved noise characteristics [49,94,156,157,158].”

    From Influences on PET Quantification and Interpretation (2022) · cites this paper as [157]

    The Discussion (page unavailable) reports improved signal-to-noise ratio with TOF, but says TOF did not appear to improve noise at the same iteration number; it attributes noise improvement chiefly to PSF. The Phantom Studies report less noise for PSF-plus-TOF at a different iteration setting, so the unqualified claim about OSEM with TOF overstates this source. (LLM, conf=0.87)

    Experimental — accuracy not yet measured

  • PSF compensation can increase the SNR and subjectively rated image quality.

    “PSF compensation can also increase the SNR [157,158] and thereby the subjectively rated image quality [157,161,162].”

    From Influences on PET Quantification and Interpretation (2022) · cites this paper as [157]

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References 40 · Cited by 206

Research works printed but not linked: 32

  1. Delbeke D. Oncological applications of FDG PET imaging: brain tumors, colorectal cancer, lymphoma and melanoma. J Nucl Med. 1999;40:591- 603.
  2. Hicks RJ, Kalff V, MacManus MP, et al. The utility of 18 F-FDG PET for sus- pected recurrent non-small cell lung cancer after potentially curative therapy: impact on management and prognostic stratification. J Nucl Med. 2001;42:1605- 1613.
  3. Oyen WJ, Bussink J, Verhagen AF, Corstens FH, Bootsma GP. Role of FDG-PET in the diagnosis and management of lung cancer. Expert Rev Anticancer Ther. 2004;4:561-567.
  4. Vansteenkiste J, Fischer BM, Dooms C, Mortensen J. Positron-emission tomo- graphy in prognostic and therapeutic assessment of lung cancer: systematic re- view. Lancet Oncol. 2004;5:531-540.
  5. Fletcher JW, Djulbegovic B, Soares HP, et al. Recommendations on the use of 18 F-FDG PET in oncology. J Nucl Med. 2009;49:480-508.
  6. Okubo M, Nishimura Y, Nakamatsu K, et al. Radiation treatment planning using positron emission and computed tomography for lung and pharyngeal cancers: a multiple-threshold method for [ 18 F]fluoro-2-deoxyglucose activity. Int J Radiat Oncol Biol Phys. 2010;77:350-356.
  7. Halpern BS, Dahlbom M, Quon A, et al. Impact of patient weight and emission scan duration on PET/CT image quality and lesion detectability. J Nucl Med. 2004;45:797-801.
  8. Tong S, Alessio AM, Kinahan PE. Noise and signal properties in PSF-based fully 3D PET image reconstruction: an experimental evaluation. Phys Med Biol. 2010;55:1453-1473.
  9. Alessio AM, Stearns CW, Tong S, et al. Application and evaluation of a measured spatially variant system model for PET image reconstruction. IEEE Trans Med Imaging. 2010;29:938-949.
  10. Surti S, Karp JS, Popescu LM, Daube-Witherspoon ME, Werner M. Investigation of time-of-flight benefit for fully 3-D PET. IEEE Trans Med Imaging. 2006; 25:529-538.
  11. Anger HO. Survey of radioisotope cameras. ISA Trans. 1966;5:311-334.
  12. Brownell GL, Burnham CA, Wilensky S, Aronow S, Kazemi H, Streider D. New developments in positron scintigraphy and the application of cyclotron produced positron emitters. In: Medical Radioisotope Scintigraphy. Vol 1. Vienna, Austria: International Atomic Energy Agency; 1969:163-176.
  13. Allemand R, Gresset C, Vacher J. Potential advantages of a cesium fluoride scintillator for a time-of-flight positron camera. J Nucl Med. 1980;21:153-155.
  14. Moses WW, Derenzo SE. Prospects for time-of-flight PET using LSO scintillator. IEEE Trans Nucl Sci. 1999;46:474-478.
  15. Melcher CL, Schweither JS. Cerium-doped lutetium oxyorthosilicate: a fast, efficient new scintillator. IEEE Trans Nucl Sci. 1992;39:502-505.
  16. Daghighiam F, Shenderov P, Pentlow KS, et al. Evaluation of cerium doped lutetium oxyorthosilicate (LSO) scintillation crystal for PET. IEEE Trans Nucl Sci. 1993;40:1045-1047.
  17. Lois C, Jakoby BW, Long MJ, et al. An assessment of the impact of incorpo- rating time-of-flight information into clinical PET/CT imaging. J Nucl Med. 2010;51:237-245.
  18. Kadrmas DJ, Casey ME, Conti M, Jakoby BW, Lois C, Townsend DW. Impact of time-of-flight on PET tumor detection. J Nucl Med. 2009;50:1315-1323.
  19. Karp JS, Surti S, Daube-Witherspoon ME, Muehllehner G. Benefit of time-of- flight in PET: experimental and clinical results. J Nucl Med. 2008;49:462-470.
  20. El Fakhri G, Surti S, Trott CM, Scheuermann J, Karp JS. Improvement in lesion detection with whole-body oncologic time-of-flight PET. J Nucl Med. 2011; 52:347-353.
  21. Surti S, Scheuermann J, El Fakhri G, et al. Impact of time-of-flight PET on whole-body oncologic studies: a human observer lesion detection and localiza- tion study. J Nucl Med. 2011;52:712-719.
  22. Fukukita H, Senda M, Terauchi T, et al. Japanese guideline for the oncology FDG-PET/CT data acquisition protocol: synopsis of version 1.0. Ann Nucl Med. 2010;24:325-334.
  23. Paquet N, Albert A, Foidart J, Hustinx R. Within-patient variability of 18 F-FDG: standardized uptake values in normal tissues. J Nucl Med. 2004;45:784-788.
  24. Badawi RD, Dahlbom M. NEC: some coincidences are more equivalent than others. J Nucl Med. 2005;46:1767-1768.
  25. Thielemans K, Asma E, Ahn S, et al. Impact of PSF modeling on the conver- gence rate and edge behavior of EM images in PET. IEEE Nucl Sci Symp Conf Rec. 2010;3267-3272.
  26. Bettinardi V, Presotto L, Rapisarda E, Picchio M, Gianolli L, Gilardi MC. Phys- ical performance of the new hybrid PET/CT Discovery-690. Med Phys. 2011;38:5394-5411.
  27. Conti M. Focus on time-of-flight PET: the benefits of improved time resolution. Eur J Nucl Med Mol Imaging. 2011;38:1147-1157.
  28. Nagaki A, Onoguchi M, Matsutomo N. Patient weight-based acquisition protocols to optimize 18 F-FDG PET/CT image quality. J Nucl Med Technol. 2011;39:72-76.
  29. Strother SC, Casey ME, Hoffman EJ. Measuring PET scanner sensitivity: re- lating countrates to image signal-to-noise ratios using noise equivalent counts. IEEE Trans Nucl Sci. 1990;37:783-788.
  30. Lartizien C, Comtat C, Kinahan PE, Ferreira N, Bendriem B, Trebossen R. Optimization of injected dose based on noise equivalent count rates for 2-and 3-dimensional whole-body PET. J Nucl Med. 2002;43:1268-1278.
  31. Masuda Y, Kondo C, Matsuo Y, Uetani M, Kusakabe K. Comparison of imaging protocols for 18 F-FDG PET/CT in overweight patients: optimizing scan duration versus administered dose. J Nucl Med. 2009;50:844-848.
  32. Tatsumi M, Clark PA, Nakamoto Y, Wahl RL. Impact of body habitus on quan- titative and qualitative image quality in whole-body FDG-PET. Eur J Nucl Med Mol Imaging. 2003;30:40-45.

Authors
Akamatsu, G., Ishikawa, K., Mitsumoto, K., Taniguchi, T., Ohya, N., Baba, S., Abe, K., & Sasaki, M.
Affiliations
  • Kyushu University (JP)
  • Kyushu University Hospital (JP)
ORCID
Venue
Journal of Nuclear Medicine
Publisher
Society of Nuclear Medicine
Published
2012-09-04
Volume
53
Issue
11
Pages
1716-1722
ISSN
  • 0161-5505 (ISSN-L)
  • 2159-662X
DOI
10.2967/jnumed.112.103861
OpenAlex
W2104614756
Cited by
206
References
40
Citations by year
2026: 5 · 2025: 9 · 2024: 7 · 2023: 22 · 2022: 19 · 2021: 17 · 2020: 13 · 2019: 7 · 2018: 18 · 2017: 18 · 2016: 16 · 2015: 26 · 2014: 16 · 2013: 12
FWCI
13.04
Type
journal article
Language
en
Open access
Locations
  • Journal of Nuclear Medicine (publishedVersion)
  • PubMed (publishedVersion)
Funders
Japan Society for the Promotion of Science (22611012)
Topics
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Medical Imaging Techniques and Applications
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Radiation Dose and Imaging
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Cardiac Imaging and Diagnostics
Keywords
point spread function, time-of-flight, 18F-FDG, OSEM, image reconstruction parameters, noise equivalent counts, signal-to-noise ratio, contrast recovery, contrast-to-noise ratio, coefficient of variation, full width at half maximum
MeSH terms
Humans, Image Processing, Computer-Assisted, Middle Aged, Quality Control, Time Factors, Tomography, X-Ray Computed, Colorectal Neoplasms, Phantoms, Imaging, Positron-Emission Tomography, Multimodal Imaging

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