Combined MRI-PET scanner: A Monte Carlo evaluation of the improvements in PET resolution due to the effects of a static homogeneous magnetic field

Journal Article · Thu Aug 01 04:00:00 EDT 1996 · IEEE Transactions on Nuclear Science

DOI:https://doi.org/10.1109/23.531789· OSTI ID:376045

Raylman, R R ^[1]; Hammer, B E ^[2]; Christensen, N L ^[3]

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1. Univ. of Michigan, Ann Arbor, MI (United States)
2. Univ. of Minnesota, Minneapolis, MN (United States). Dept. of Radiology
3. Univ. of Auckland (New Zealand). Dept. of Physics

Positron emission tomography (PET) relies upon the detection of photons resulting from the annihilation of positrons emitted by a radiopharmaceutical. The combination of images obtained with PET and magnetic resonance imaging (MRI) have begun to greatly enhance the study of many physiological processes. A combined MRI-PET scanner could alleviate much of the spatial and temporal coregistration difficulties currently encountered in utilizing images from these complementary imaging modalities. In addition, the resolution of the PET scanner could be improved by the effects of the magnetic field. In this computer study, the utilization of a strong static homogeneous magnetic field to increase PET resolution by reducing the effects of positron range and photon noncollinearity was investigated. The results reveal that significant enhancement of resolution can be attained. For example, an approximately 27% increase in resolution is predicted for a PET scanner incorporating a 10-Tesla magnetic field. Most of this gain in resolution is due to magnetic confinement of the emitted positrons. Although the magnetic field does mix some positronium states resulting in slightly less photon noncollinearity, this reduction does not significantly affect resolution. Photon noncollinearity remains as the fundamental limiting factor of large PET scanner resolution.

• OSTI ID: 376045
• Journal Information: IEEE Transactions on Nuclear Science, Journal Name: IEEE Transactions on Nuclear Science Journal Issue: 4Pt2 Vol. 43; ISSN 0018-9499; ISSN IETNAE
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
DESIGN
HYBRID SYSTEMS
IMAGES
NMR IMAGING
PERFORMANCE
POSITRON COMPUTED TOMOGRAPHY
RADIOISOTOPE SCANNERS
SPATIAL RESOLUTION