Birdcage resonator

The whole NMR imaging sensor system usually consists of a magnet, a shim system mounted inside the room-temperature bore of the magnet, a gradient system mounted inside the shim system and the rf coil mounted inside the gradient system. In the case of a saddle coil or a birdcage resonator, open access can be realized from the bottom to the top of the entire system with the coil diameter. 

Fig. 2.3.7 Birdcage resonator. The capacitances are distributed for cylindrical surface currents (cf. Fig. 2.4.6(a)) to generate an rf field transverse to the axial direction.

All experiments were performed in a 1.9-T horizontal bore magnet (Oxford Instruments, Oxford, UK) with a dear bore diameter of 31 cm. Magnetic field gradients were produced by a 12-cm id water-cooled gradient set (Resonance Research, Billerica, MA, USA), capable of a maximum output of 300 mT m-1, and were driven by Techron 7700 amplifiers (Techron Inc., Elkhart, IN, USA). Rf excitation was accomplished using either a quadrature driven birdcage coil (Morris Instruments, Ottawa, ON, Canada), or an 8-tum laboratory-built solenoid coil, driven by an ENI LPI-10 1000 W amplifier or a Matec Model 525 class-C amplifier. 

Y. Duan, B. S. Peterson, F. Liu, T. R. Brown, T. S. Ibrahim and A. Kangarlu, Computational and experimental optimization of a double-tuned H/ P four-ring birdcage head coil for MRS at 3T. /. Magn. Reson. Imaging, 2009, 29,13-22. 

The imaging experiments were performed using the same imaging system described in section 2.4. A 4.4-cm i.d. birdcage RF resonator was used for both... 

Schenck, J. F., E. B. Boskamp, D. J. Schaefer, W. D. Barber, and R. H. Vander Heiden, 1998, Estimating Local SAR Produced by RF Transminer Q>ils Examples Using the Birdcage Coil. Abstracts of the International Society of Magnetic Resonance in Medicine, Sixth Meeting, Sydney, p. 649. 

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