Development of a new RF coil and gamma-ray radiation shielding assembly for improved MR image quality in SPECT/MRI. Phys Med Biol 2010 May 07;55(9):2495-504
Date
04/08/2010Pubmed ID
20371909DOI
10.1088/0031-9155/55/9/005Scopus ID
2-s2.0-77951163738 (requires institutional sign-in at Scopus site) 10 CitationsAbstract
Magnetic resonance (MR)-based multimodality imaging systems, such as single-photon emission tomography (SPECT)/magnetic resonance imaging (MRI) or positron emission tomography (PET)/MRI, face many difficulties because of problems with the compatibility of the nuclear detector system with the MR system. However, several studies have reported on the design considerations of MR-compatible nuclear detectors for combined SPECT/MRI. In this study, we developed a new radiofrequency (RF) coil and gamma-ray radiation shielding assembly to advance the practical implementation of SPECT/MRI in providing high sensitivity while minimizing the interference between the MRI and SPECT systems. The proposed assembly consists of a three-channel receive-only RF coil and gamma-ray radiation shields made of a specialized lead composite powder designed to reduce conductivity and thus minimizing any effect on the magnetic field arising from the induced eddy currents. A conventional birdcage RF coil was also tested for comparison with the proposed RF coil. Quality (Q)-factors were measured using both RF coils without any shielding, with solid lead shielding, and with our composite lead shielding. Signal-to-noise ratios (SNRs) were calculated using 4 T MR images of phantoms both with and without the new gamma-ray radiation shields. The Q-factor and SNR measurements demonstrate the improved MRI performance due to the new RF coil/gamma-ray radiation shield assembly designed for SPECT/MRI, making it a useful addition to multimodality imaging technology not only for animal studies but also for in vivo study of humans.
Author List
Ha S, Hamamura MJ, Roeck WW, Muftuler LT, Nalcioglu OAuthor
Lutfi Tugan Muftuler PhD Professor in the Neurosurgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsGamma Rays
Image Enhancement
Magnetic Resonance Imaging
Phantoms, Imaging
Radiation Protection
Radio Waves
Tomography, Emission-Computed, Single-Photon