Dataset Information

Phantom-based image quality assessment of clinical ¹⁸F-FDG protocols in digital PET/CT and comparison to conventional PMT-based PET/CT.

ABSTRACT:

Background

We assessed and compared image quality obtained with clinical ¹⁸F-FDG whole-body oncologic PET protocols used in three different, state-of-the-art digital PET/CT and two conventional PMT-based PET/CT devices. Our goal was to evaluate an improved trade-off between administered activity (patient dose exposure/signal-to-noise ratio) and acquisition time (patient comfort) while preserving diagnostic information achievable with the recently introduced digital detector technology compared to previous analogue PET technology.

Methods

We performed list-mode (LM) PET acquisitions using a NEMA/IEC NU2 phantom, with activity concentrations of 5?kBq/mL and 25?kBq/mL for the background (9.5?L) and sphere inserts, respectively. For each device, reconstructions were obtained varying the image statistics (10, 30, 60, 90, 120, 180, and 300?s from LM data) and the number of iterations (range 1 to 10) in addition to the employed local clinical protocol setup. We measured for each reconstructed dataset: the quantitative cross-calibration, the image noise on the uniform background assessed by the coefficient of variation (COV), and the recovery coefficients (RCs) evaluated in the hot spheres. Additionally, we compared the characteristic time-activity-product (TAP) that is the product of scan time per bed position × mass-activity administered (in min·MBq/kg) across datasets.

Results

Good system cross-calibration was obtained for all tested datasets with ConclusionsThis study compared the achievable clinical image quality in three state-of-the-art digital PET/CT devices (from different vendors) as well as in two conventional PMT-based PET. Reported results show that a comparable image quality is achievable with a TAP reduction of ~?40% in digital PET. This could lead to a significant reduction of the administered mass-activity and/or scan time with direct benefits in terms of dose exposure and patient comfort.

SUBMITTER: Gnesin S

PROVIDER: S-EPMC6944719 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Publications

Phantom-based image quality assessment of clinical <sup>18</sup>F-FDG protocols in digital PET/CT and comparison to conventional PMT-based PET/CT.

Gnesin Silvano S Kieffer Christine C Zeimpekis Konstantinos K Papazyan Jean-Pierre JP Guignard Renaud R Prior John O JO Verdun Francis R FR Lima Thiago V M TVM

EJNMMI physics 20200106 1

<h4>Background</h4>We assessed and compared image quality obtained with clinical <sup>18</sup>F-FDG whole-body oncologic PET protocols used in three different, state-of-the-art digital PET/CT and two conventional PMT-based PET/CT devices. Our goal was to evaluate an improved trade-off between administered activity (patient dose exposure/signal-to-noise ratio) and acquisition time (patient comfort) while preserving diagnostic information achievable with the recently introduced digital detector t ...[more]

PMID: 31907664

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