Highlights
- •The ability of reconstruction algorithms to correct for partial volume effect is controversial.
- •Iterative reconstructions with and without TOF achieve activity recovery in the 22 mm sphere.
- •Resolution recovery and noise modelling algorithms achieved considerable activity recovery in the intermediate spheres (in particular in the 17 mm diameter sphere).
- •There is no activity recovery gain in the smallest sphere (6 mm diameter) using neither PSF, nor TOF nor BPL.
Abstracts
The reconstruction algorithms implemented on PET/CT scanners offer gain in activity
recovery of small lesions at an extent that is not full known yet.
Methods
A cylindrical phantom with warm background and hot spheres filled with a 68Ge epoxy was acquired with four non-state-solid-detectors PET/CT scanners: mCT, Ingenuity
TF, Discovery 710, and IQ. Images were reconstructed switching on and off time-of-flight
(TOF), point spread function (PSF) modelling, and Bayesian penalised likelihood (BPL).
Images were reconstructed with the default parameters recommended by the manufacturers.
The recovery coefficient (RCmax), defined as the ratio of the measured maximum activity concentration in each sphere
and the actual one, and the coefficient of variation (CoVBAC) defined as the ratio of the standard deviation and the average of background activity
concentration were measured.
Results
While with IR alone, complete recovery of the activity concentration is achieved down
to the 22 mm diameter’s sphere, with TOF, TOF + PSF and BPL it is achieved down to
the 17 mm diameter one. At smaller dimensions, the difference among the various studied
reconstruction algorithms is substantial for the 13- and 17-mm diameters’ spheres
for all scanners and for all reconstructions with a considerable gain in RCmax when
PSF and BPL are used. At 10 mm diameter’s sphere the difference among the algorithms
is significantly reduced, except for BPL which still guarantees a gain in RCmax.
Keywords
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to Physica Medica: European Journal of Medical PhysicsAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- The new opportunities for high time resolution clinical TOF PET.Clin Transl Imaging. 2019; 7: 139-147
- Recent developments in time-of-flight PET.EJNMMI Phys. 2016; 3: 3
- Advances in time-of-flight PET.Phys Medica. 2016; 32: 12-22
- Quantification, improvement, and harmonization of small lesion detection with state-of-the-art PET.Eur J Nucl Med Mol Imaging. 2017; 44: 4-16
- Geometry study of a high resolution pet detection system using small detectors.IEEE Trans Nucl Sci. 1984; 31: 556-561
- Modeling and incorporation of system response functions in 3-D whole body PET.IEEE Trans Med Imaging. 2006; 25: 828-837
- Fully 3-D PET reconstruction with system matrix derived from point source measurements.IEEE Trans Med Imaging. 2006; 25: 907-921
Casey M. Point Spread Function Reconstruction in PET - Siemens Whitepaper; 2007.
Narayanan M, Perkins A. Resolution recovery in the Ingenuity TF PET/CT - Philips Whitepaper; 2013.
- Resolution modeling in PET imaging: theory, practice, benefits, and pitfalls.Med Phys. 2013; 40: 064301-64315
- Standardized uptake values for [18F] FDG in normal organ tissues: Comparison of whole-body PET/CT and PET/MRI.Eur J Radiol. 2013; 1–7
- Performance comparison of two resolution modeling PET reconstruction algorithms in terms of physical figures of merit used in quantitative imaging.Phys Medica. 2015; 31: 468-475
- Optimal reconstruction matrix and PET image filtration for point-spread function and time-of-flight reconstruction – A phantom study.Phys Medica. 2017; 39: 95-99
- Harmonizing standardized uptake value recovery between two PET/CT systems from different manufacturers when using resolution modelling and time-of-flight.Nucl Med Commun. 2017; 38: 650-655
- Point-spread function reconstructed PET images of sub-centimeter lesions are not quantitative.EJNMMI Phys. 2017; 4: 1-12
Ross S. Q. Clear - General Electric Company Whitepaper; 2014.
- Physica Medica Bayesian penalized-likelihood reconstruction algorithm suppresses edge artifacts in PET reconstruction based on point-spread-function.Phys Medica. 2018; 47: 73-79
- Treatment response assessment in [18 F]FDG-PET/CT oncology scans: Impact of count statistics variation and reconstruction protocol.Phys Medica. 2019; 57: 177-182
- Instrumentation factors affecting variance and bias of quantifying tracer uptake with PET/CT.Med Phys. 2010; 37: 6035-6046
- Biases in Multicenter Longitudinal PET Standardized Uptake Value Measurements.Transl Oncol. 2014; 7: 48-54
- The68Ge phantom-based FDG-PET site qualification program for clinical trials adopted by FIL (Italian Foundation on Lymphoma).Phys Medica. 2016; 32: 651-656
- Evaluation of Cross-Calibrated 68 Ge/68 Ga Phantoms for Assessing PET/CT Measurement Bias in Oncology Imaging for Single- and Multicenter Trials.Tomography. 2017; 2: 353-360
- Noise and signal properties in PSF-based fully 3D PET image reconstruction: an experimental evaluation.Phys Med Biol. 2010; 55: 1453-1473
- FDG PET, CT: EANM procedure guidelines for tumour imaging: version 2.0.Eur J Nucl Med Mol Imaging. 2014; 42: 328-354
- Quantitative comparison of PET performance—siemens biograph mCT and mMR.EJNMMI Phys. 2016; 3
- Comparison between new-generation SiPM-based and conventional PMT-based TOF-PET/CT.Phys Medica. 2017; 42: 203-210
- Physical and clinical performance of the mCT time-of-flight PET/CT scanner.Phys Med Biol. 2011; 56: 2375-2389
- Resolution modeling in PET imaging: Theory, practice, benefits, and pitfalls.Med Phys. 2013; 40
- Assessment of tumor size reduction improves outcome prediction of positron emission tomography/computed tomography after chemotherapy in advanced-stage Hodgkin lymphoma.J Clin Oncol. 2014; 32: 1776-1781
Barrington SF, Sulkin T, Forbes A, Johnson PWM, Barrington SF. All that glitters is not gold - new reconstruction methods using Deauville criteria for patient reporting; 2018:316-317.
- The use of a proposed updated EARL harmonization of 18F-FDG PET-CT in patients with lymphoma yields significant differences in Deauville score compared with current EARL recommendations.EJNMMI Res. 2019; 9
- Harmonizing SUVs in multicentre trials when using different generation PET systems: prospective validation in non-small cell lung cancer patients.Eur J Nucl Med Mol Imaging. 2013; 40: 985-996
Article info
Publication history
Published online: June 16, 2020
Accepted:
June 1,
2020
Received in revised form:
May 4,
2020
Received:
December 14,
2019
Identification
Copyright
© 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
