Feasibility of state of the art PET/CT systems performance harmonisation
Open accessAbstract
PURPOSE: The objective of this study was to explore the feasibility of harmonising performance for PET/CT systems equipped with time-of-flight (ToF) and resolution modelling/point spread function (PSF) technologies. A second aim was producing a working prototype of new harmonising criteria with higher contrast recoveries than current EARL standards using various SUV metrics. METHODS: Four PET/CT systems with both ToF and PSF capabilities from three major vendors were used to acquire and reconstruct images of the NEMA NU2-2007 body phantom filled conforming EANM EARL guidelines. A total of 15 reconstruction parameter sets of varying pixel size, post filtering and reconstruction type, with three different acquisition durations were used to compare the quantitative performance of the systems. A target range for recovery curves was established such that it would accommodate the highest matching recoveries from all investigated systems. These updated criteria were validated on 18 additional scanners from 16 sites in order to demonstrate the scanners' ability to meet the new target range. RESULTS: Each of the four systems was found to be capable of producing harmonising reconstructions with similar recovery curves. The five reconstruction parameter sets producing harmonising results significantly increased SUVmean (25%) and SUVmax (26%) contrast recoveries compared with current EARL specifications. Additional prospective validation performed on 18 scanners from 16 EARL accredited sites demonstrated the feasibility of updated harmonising specifications. SUVpeak was found to significantly reduce the variability in quantitative results while producing lower recoveries in smaller (≤17 mm diameter) sphere sizes. CONCLUSIONS: Harmonising PET/CT systems with ToF and PSF technologies from different vendors was found to be feasible. The harmonisation of such systems would require an update to the current multicentre accreditation program EARL in order to accommodate higher recoveries. SUVpeak should be further investigated as a noise resistant alternative quantitative metric to SUVmax.
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Compared with non-PSF reconstructed images, PSF can increase lesion SUVmax, SUVmean and SUVpeak by up to 30% on average.
“Compared with non-PSF reconstructed images, this can increase lesion SUVmax, SUVmean and SUVpeak by up to 30% on average [100,101,102].”
From Influences on PET Quantification and Interpretation (2022) · cites this paper as [101]
The Abstract Results report 25% higher SUVmean and 26% higher SUVmax contrast recoveries for proposed reconstructions, compared with current EARL specifications. The Discussion also says PSF can introduce positive SUV bias, particularly for SUVmax. The paper does not establish an average increase of up to 30% for all three lesion metrics—including SUVpeak—relative to non-PSF images; its reported recoveries are from phantom spheres. (LLM, conf=0.88)
Experimental — accuracy not yet measuredPL reconstruction can lead to overestimation of true activity in larger lesions if SUVmax is used, but the increase in CR may be especially prominent in microspheres with diameters <10 mm, where conventional algorithms usually underestimate true activity substantially.
“Although this effect can lead to overestimation of the true activity in larger lesions if the SUVmax is used [101], the increase in CR may be especially prominent in microspheres with diameters <10 mm, in which conventional algorithms usually underestimate the true activity substantially [109].”
From Influences on PET Quantification and Interpretation (2022) · cites this paper as [101]
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Experimental — accuracy not yet measuredThe test-retest variability of lesion SUVs has undermined attempts to establish widely adoptable SUV thresholds unless rigorous harmonization measures are followed.
“This has undermined any attempts to establish widely adoptable SUV thresholds unless rigorous harmonization measures are followed [101,103,181].”
From Influences on PET Quantification and Interpretation (2022) · cites this paper as [101]
The Results (page not provided) show substantial variation in SUV recovery across PET/CT systems and reconstruction modes, and the Discussion says harmonisation is necessary for reliable use of SUVmax. The paper does not establish that test-retest variability of lesion SUVs has undermined attempts to set widely adoptable SUV thresholds; its reported variation is primarily across systems and reconstruction modes. (LLM, conf=0.84)
Experimental — accuracy not yet measuredUsing a commercially available PL reconstruction (GE Q.Clear), phantom studies have shown that PL reconstruction can increase CR of standardized sphere inserts compared to conventional TOF and PSF reconstruction.
“Using a commercially available PL reconstruction (General Electric [GE] Q.Clear), several phantom studies have shown that PL reconstruction can increase the CR of standardized sphere inserts compared to conventional TOF and PSF reconstruction [41,46,101,107,108].”
From Influences on PET Quantification and Interpretation (2022) · cites this paper as [101]
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Quantitative implications of the updated EARL 2019 PET–CT performance standards
Kaalep, A., Burggraaff, C. N., Pieplenbosch, S., Verwer, E. E., Sera, T., Zijlstra, J., Hoekstra, O. S., Oprea-Lager, D. E., & Boellaard, R. (2019) · EJNMMI Physics · doi:10.1186/s40658-019-0257-8 · Cited by 79 · see citing works
Self-citationNew PET technologies – embracing progress and pushing the limits
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Influences on PET Quantification and Interpretation
Rogasch, J. M. M., Hofheinz, F., van Heek, L., Voltin, C.-A., Boellaard, R., & Kobe, C. (2022) · Diagnostics · doi:10.3390/diagnostics12020451 · Cited by 50 · see citing works
“This has undermined any attempts to establish widely adoptable SUV thresholds unless rigorous harmonization measures are followed [101,103,181].”
BackgroundSelf-citationLy, J., Minarik, D., Edenbrandt, L., Wollmer, P., & Trägårdh, E. (2019) · EJNMMI Research · doi:10.1186/s13550-019-0536-3 · Cited by 31 · see citing works
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- Authors
- Kaalep, A., Sera, T., Rijnsdorp, S., Yaqub, M., Talsma, A., Lodge, M. A., & Boellaard, R.
- Affiliations
- North Estonia Medical Centre (EE)
- Catharina Ziekenhuis (NL)
- Gemeente Amsterdam (NL)
- Martini Ziekenhuis (NL)
- Johns Hopkins University (US)
- University Medical Center Groningen (NL)
- Corresponding author
- Kaalep, Andres
- Boellaard, Ronald
- Venue
- European Journal of Nuclear Medicine and Molecular Imaging
- Published
- 2018-03-02
- Volume
- 45
- Issue
- 8
- Pages
- 1344-1361
- ISSN
- 1619-7070 (ISSN-L)
- 1619-7089
- PMC
- PMC5993859
- OpenAlex
- W2790159993
- Cited by
- 160
- References
- 3
- Citations by year
- 2026: 12 · 2025: 18 · 2024: 16 · 2023: 20 · 2022: 21 · 2021: 29 · 2020: 22 · 2019: 16 · 2018: 5
- FWCI
- 12.44
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- European Journal of Nuclear Medicine and Molecular Imaging (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Pure Amsterdam UMC (publishedVersion, cc-by)
- University of Groningen research database (University of Groningen / Centre for Information Technology) (publishedVersion, cc-by)
- SZTE Publicatio Repozitórium (University of Szeged) (acceptedVersion, other-oa)
- Amsterdam UMC (VU Amsterdam) - Institutional Repository (submittedVersion, other-oa)
- University of Groningen research database (University of Groningen / Centre for Information Technology) (submittedVersion, cc-by)
- Data Archiving and Networked Services (DANS) (submittedVersion, other-oa)
- 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
- PET/CT, time-of-flight PET, point spread function reconstruction, standardized uptake value, SUVpeak, SUVmax, SUVmean
- MeSH terms
- Accreditation, Positron Emission Tomography Computed Tomography, Humans, Prospective Studies, Phantoms, Imaging, Positron-Emission Tomography
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