Dataset Information

Optimal ^99mTc activity ratio in the single-day stress-rest myocardial perfusion imaging protocol: A multi-SPECT phantom study.

ABSTRACT:

Background

This investigation used image data generated by an anthropomorphic phantom to determine the minimal ^99mTc rest-stress activity concentration ratio (R) able to minimize the ghosting effect in the single-day stress-first myocardial perfusion imaging, using different positions of the perfusion defect (PD), scanners and reconstruction protocols.

Methods

A cardiac phantom with a simulated PD was imaged under different R using different gamma cameras and reconstruction algorithms. The residual activity from precedent stress administration was simulated by modeling effective half-times in each compartment of the phantom and assuming a delay of 3 hours between the stress and rest studies. The net contrast (NC) of the PD in the rest study was assessed for different R, PD positions and scanner/software combinations. The optimal R will be the one that minimize the NC in the rest images RESULTS: The activity concentration ratio R, the position of the PD and the scanner/software combinations were all main effects with a statistically significant impact on the NC, in decreasing order of relevance. The NC diminished significantly only for R values up to 2. No further improvement was observed for NC for R values above 2 and up to 3. NC was significantly higher in anteroseptal than in posterolateral positions of the PD and higher for solid-state cameras.

Conclusions

A rest-stress activity concentration ratio R of 2 in single-day stress-first myocardial perfusion imaging is enough to achieve the maximum net contrast in the PD. This ratio should be used to optimize patient's radiation exposure.

SUBMITTER: Zoccarato O

PROVIDER: S-EPMC7384561 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Publications

Optimal <sup>99m</sup>Tc activity ratio in the single-day stress-rest myocardial perfusion imaging protocol: A multi-SPECT phantom study.

Zoccarato Orazio O Matheoud Roberta R Lecchi Michela M Scabbio Camilla C Claudio Marcassa M Brambilla Marco M

Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology 20200727 1

<h4>Background</h4>This investigation used image data generated by an anthropomorphic phantom to determine the minimal <sup>99m</sup>Tc rest-stress activity concentration ratio (R) able to minimize the ghosting effect in the single-day stress-first myocardial perfusion imaging, using different positions of the perfusion defect (PD), scanners and reconstruction protocols.<h4>Methods</h4>A cardiac phantom with a simulated PD was imaged under different R using different gamma cameras and reconstruc ...[more]

PMID: 32720060

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Dataset Information

Optimal ^99mTc activity ratio in the single-day stress-rest myocardial perfusion imaging protocol: A multi-SPECT phantom study.

Background

Methods

Conclusions

Publications

Optimal <sup>99m</sup>Tc activity ratio in the single-day stress-rest myocardial perfusion imaging protocol: A multi-SPECT phantom study.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Optimal 99mTc activity ratio in the single-day stress-rest myocardial perfusion imaging protocol: A multi-SPECT phantom study.

Background

Methods

Conclusions

Publications

Optimal <sup>99m</sup>Tc activity ratio in the single-day stress-rest myocardial perfusion imaging protocol: A multi-SPECT phantom study.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Optimal ^99mTc activity ratio in the single-day stress-rest myocardial perfusion imaging protocol: A multi-SPECT phantom study.