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01.08.2012 | Molecular Imaging

Technical performance evaluation of a human brain PET/MRI system

verfasst von: Armin Kolb, Hans F. Wehrl, Matthias Hofmann, Martin S. Judenhofer, Lars Eriksson, Ralf Ladebeck, Matthias P. Lichy, Larry Byars, Christian Michel, Heinz-Peter Schlemmer, Matthias Schmand, Claus D. Claussen, Vesna Sossi, Bernd J. Pichler

Erschienen in: European Radiology | Ausgabe 8/2012

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Abstract

Objectives

Technical performance evaluation of a human brain PET/MRI system.

Methods

The magnetic field compatible positron emission tomography (PET) insert is based on avalanche photodiode (APD) arrays coupled with lutetium oxyorthosilicate (LSO) crystals and slip-fits into a slightly modified clinical 3-T MRI system. The mutual interference between the two imaging techniques was minimised by the careful design of the hardware to maintain the quality of the B ₀ and B ₁ field homogeneity.

Results

The signal-to-noise ratio (SNR) and the homogeneity of the MR images were minimally influenced by the presence of the PET. Measurements according to the Function Biomedical Informatics Research Network (FBIRN) protocol proved the combined system’s ability to perform functional MRI (fMRI). The performance of the PET insert was evaluated according to the National Electrical Manufacturers Association (NEMA) standard. The noise equivalent count rate (NEC) peaked at 30.7 × 10³ counts/s at 7.3 kBq/mL. The point source sensitivity was greater than 7 %. The spatial resolution in the centre field of view was less than 3 mm. Patient data sets clearly revealed a noticeably good PET and MR image quality.

Conclusion

PET and MRI phantom tests and first patient data exhibit the device’s potential for simultaneous multiparametric imaging.

Key Points

• Combination of PET and MRI is a new emerging imaging technology.

• Evaluated brain PET/MRI enables uncompromised imaging performance.

• PET/MRI aims to provide multiparametric imaging allowing acquisition of morphology and metabolism.

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Titel: Technical performance evaluation of a human brain PET/MRI system
verfasst von: Armin Kolb
Hans F. Wehrl
Matthias Hofmann
Martin S. Judenhofer
Lars Eriksson
Ralf Ladebeck
Matthias P. Lichy
Larry Byars
Christian Michel
Heinz-Peter Schlemmer
Matthias Schmand
Claus D. Claussen
Vesna Sossi
Bernd J. Pichler
Publikationsdatum: 01.08.2012
Verlag: Springer-Verlag
Erschienen in: European Radiology / Ausgabe 8/2012
Print ISSN: 0938-7994
Elektronische ISSN: 1432-1084
DOI: https://doi.org/10.1007/s00330-012-2415-4

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Technical performance evaluation of a human brain PET/MRI system