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European Journal of Nuclear Medicine and Molecular Imaging

Published in:

01-07-2017 | Original Article

Clinical evaluation of TOF versus non-TOF on PET artifacts in simultaneous PET/MR: a dual centre experience

Authors: Edwin E. G. W. ter Voert, Patrick Veit-Haibach, Sangtae Ahn, Florian Wiesinger, M. Mehdi Khalighi, Craig S. Levin, Andrei H. Iagaru, Greg Zaharchuk, Martin Huellner, Gaspar Delso

Published in: European Journal of Nuclear Medicine and Molecular Imaging | Issue 7/2017

Abstract

Purpose

Our objective was to determine clinically the value of time-of-flight (TOF) information in reducing PET artifacts and improving PET image quality and accuracy in simultaneous TOF PET/MR scanning.

Methods

A total 65 patients who underwent a comparative scan in a simultaneous TOF PET/MR scanner were included. TOF and non-TOF PET images were reconstructed, clinically examined, compared and scored. PET imaging artifacts were categorized as large or small implant-related artifacts, as dental implant-related artifacts, and as implant-unrelated artifacts. Differences in image quality, especially those related to (implant) artifacts, were assessed using a scale ranging from 0 (no artifact) to 4 (severe artifact).

Results

A total of 87 image artifacts were found and evaluated. Four patients had large and eight patients small implant-related artifacts, 27 patients had dental implants/fillings, and 48 patients had implant-unrelated artifacts. The average score was 1.14 ± 0.82 for non-TOF PET images and 0.53 ± 0.66 for TOF images (p < 0.01) indicating that artifacts were less noticeable when TOF information was included.

Conclusion

Our study indicates that PET image artifacts are significantly mitigated with integration of TOF information in simultaneous PET/MR. The impact is predominantly seen in patients with significant artifacts due to metal implants.

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Title: Clinical evaluation of TOF versus non-TOF on PET artifacts in simultaneous PET/MR: a dual centre experience
Authors: Edwin E. G. W. ter Voert
Patrick Veit-Haibach
Sangtae Ahn
Florian Wiesinger
M. Mehdi Khalighi
Craig S. Levin
Andrei H. Iagaru
Greg Zaharchuk
Martin Huellner
Gaspar Delso
Publication date: 01-07-2017
Publisher: Springer Berlin Heidelberg
Published in: European Journal of Nuclear Medicine and Molecular Imaging / Issue 7/2017
Print ISSN: 1619-7070
Electronic ISSN: 1619-7089
DOI: https://doi.org/10.1007/s00259-017-3619-2

At a glance: The STEP trials

Springer Medicine

Clinical evaluation of TOF versus non-TOF on PET artifacts in simultaneous PET/MR: a dual centre experience

Abstract

Purpose

Methods

Results

Conclusion

At a glance: The STEP trials

Springer Medicine

Abstract

Purpose

Methods

Results

Conclusion

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