Dataset Information

Evaluation of image quality with four positron emitters and three preclinical PET/CT systems.

ABSTRACT:

Background

We investigated the image quality of ¹¹C, ⁶⁸Ga, ¹⁸F and ⁸⁹Zr, which have different positron fractions, physical half-lifes and positron ranges. Three small animal positron emission tomography/computed tomography (PET/CT) systems were used in the evaluation, including the Siemens Inveon, RAYCAN X5 and Molecubes ?-cube. The evaluation was performed on a single scanner level using the national electrical manufacturers association (NEMA) image quality phantom and analysis protocol. Acquisitions were performed with the standard NEMA protocol for ¹⁸F and using a radionuclide-specific acquisition time for ¹¹C, ⁶⁸Ga and ⁸⁹Zr. Images were assessed using percent recovery coefficient (%RC), percentage standard deviation (%STD), image uniformity (%SD), spill-over ratio (SOR) and evaluation of image quantification.

Results

⁶⁸Ga had the lowest %RC (18F had the highest maximum %RC (>?85%) and lowest %STD for the 5 mm rod across all systems. For ¹¹C and ⁸⁹Zr, the maximum %RC was close (>?76%) to the %RC with ¹⁸F. A larger SOR were measured in water with ¹¹C and ⁶⁸Ga compared to ¹⁸F on all systems. SOR in air reflected image reconstruction and data correction performance. Large variation in image quantification was observed, with maximal errors of 22.73% (⁸⁹Zr, Inveon), 17.54% (⁸⁹Zr, RAYCAN) and -?14.87% (⁶⁸Ga, Molecubes).

Conclusions

The systems performed most optimal in terms of NEMA image quality parameters when using ¹⁸F, where ¹¹C and ⁸⁹Zr performed slightly worse than ¹⁸F. The performance was least optimal when using ⁶⁸Ga, due to large positron range. The large quantification differences prompt optimization not only by terms of image quality but also quantification. Further investigation should be performed to find an appropriate calibration and harmonization protocol and the evaluation should be conducted on a multi-scanner and multi-center level.

SUBMITTER: Teuho J

PROVIDER: S-EPMC7728905 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Publications

Evaluation of image quality with four positron emitters and three preclinical PET/CT systems.

Teuho Jarmo J Riehakainen Leon L Honkaniemi Aake A Moisio Olli O Han Chunlei C Tirri Marko M Liu Shihao S Grönroos Tove J TJ Liu Jie J Wan Lin L Liang Xiao X Ling Yiqing Y Hua Yuexuan Y Roivainen Anne A Knuuti Juhani J Xie Qingguo Q Teräs Mika M D'Ascenzo Nicola N Klén Riku R

EJNMMI research 20201210 1

<h4>Background</h4>We investigated the image quality of <sup>11</sup>C, <sup>68</sup>Ga, <sup>18</sup>F and <sup>89</sup>Zr, which have different positron fractions, physical half-lifes and positron ranges. Three small animal positron emission tomography/computed tomography (PET/CT) systems were used in the evaluation, including the Siemens Inveon, RAYCAN X5 and Molecubes β-cube. The evaluation was performed on a single scanner level using the national electrical manufacturers association (NEMA) ...[more]

PMID: 33301074

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Dataset Information

Evaluation of image quality with four positron emitters and three preclinical PET/CT systems.

Background

Results

Conclusions

Publications

Evaluation of image quality with four positron emitters and three preclinical PET/CT systems.

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