Molecular Imaging and Biology

, Volume 19, Issue 4, pp 626–635 | Cite as

The Effect of Defective PET Detectors in Clinical Simultaneous [18F]FDG Time-of-Flight PET/MR Imaging

  • Edwin E. G. W. ter Voert
  • Gaspar Delso
  • Felipe de Galiza Barbosa
  • Martin Huellner
  • Patrick Veit-Haibach
Research Article
First Online:

Abstract

Purpose

The purpose of this study was to evaluate the effect of defective positron emission tomography (PET) detectors on clinical PET image quality in simultaneous PET/magnetic resonance imaging (MRI) for both time-of-flight (TOF) and non-TOF reconstructed images.

Procedures

A total of six patients with various malignant tumors were included and underwent a 2-deoxy-2-[18F]fluoro-d-glucose PET scan in a fully functional simultaneous TOF PET/MRI. TOF and non-TOF PET images were reconstructed before and after simulating defective detector units. All images were clinically assessed and scored. In addition, a quantitative assessment was performed. Differences were ascertained and compared using the Wilcoxon matched pairs signed-rank test.

Results

Without TOF, the image artifacts introduced by one defective detector unit already started to degrade the overall image quality. It reduced the confidence and could lead to a change in diagnosis. Simulating three or five defective detector units resulted in more artifacts and further reduced overall image quality and confidence. By including TOF information, the effects were mitigated: Images reconstructed with one defective detector unit had similar scores as the ones without defective units. The average absolute percentage error for one, three, and five defective detector units were respectively 8, 20, and 37 % for the non-TOF cases and only 5, 11, and 19 % for the TOF cases.

Conclusion

Our study indicates that PET image artifacts due to (simulated) defective detectors are significantly mitigated with the integration of TOF information in simultaneous PET/MR. One defective detector unit introduces, on average, a 5 % absolute percentage error. However, in TOF imaging, even in cases with one or three defective units for head and neck imaging and one defective unit for chest and abdominal imaging, overall image quality, artifact scoring, and reader confidence are not significantly degraded.

Key words

Defective detectors Time-of-flight PET/MR Clinical Simulation 
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Notes

Compliance with Ethical Standards

Ethical Approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed Consent

Informed consent was obtained from all individual participants included in the study.

Conflict of Interest

Patrick Veit-Haibach received investigator-initiated study grants from Bayer Healthcare, Siemens Healthcare, and Roche Pharmaceuticals and speaker fees from GE Healthcare. G. Delso is an employee of GE Healthcare. The remaining authors declare having no conflict of interest.

Supplementary material

11307_2016_1023_MOESM1_ESM.pdf (500 kb)
ESM 1 (PDF 499 kb)

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Copyright information

© World Molecular Imaging Society 2016

Authors and Affiliations

  • Edwin E. G. W. ter Voert
    • 1
    • 2
  • Gaspar Delso
    • 3
  • Felipe de Galiza Barbosa
    • 1
    • 2
  • Martin Huellner
    • 1
    • 2
    • 4
  • Patrick Veit-Haibach
    • 1
    • 2
    • 5
  1. 1.Department of Nuclear MedicineUniversity Hospital ZurichZurichSwitzerland
  2. 2.University of ZurichZurichSwitzerland
  3. 3.GE HealthcareWaukeshaUSA
  4. 4.Department of NeuroradiologyUniversity Hospital ZurichZurichSwitzerland
  5. 5.Department of Diagnostic and Interventional RadiologyUniversity Hospital ZurichZurichSwitzerland

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