Sensitivity of an Eight-element Phased Array Coil in 3 Tesla MR Imaging: A Basic Analysis

• Published in: Magnetic Resonance in Medical Sciences 2007, Vol.6(3), pp.177-181
• Main Authors: HIRATSUKA, Yoshiyasu, MIKI, Hitoshi, KIKUCHI, Keiichi, KIRIYAMA, Ikuko, MOCHIZUKI, Teruhito, TAKAHASHI, Shizue, SADAMOTO, Kazuhiko
• Format: Article
• Language: English
• Subjects: 3T MRI; Adult; Brain - anatomy & histology; Cerebrospinal Fluid; eight-channel phased array coil; Female; Humans; Image Enhancement - instrumentation; Image Enhancement - methods; Image Enhancement - standards; Image Processing, Computer-Assisted - methods; Image Processing, Computer-Assisted - standards; image uniformity; Lateral Ventricles - anatomy & histology; Magnetic Resonance Imaging - instrumentation; Magnetic Resonance Imaging - methods; Magnetic Resonance Imaging - standards; Male; Phantoms, Imaging; sensitivity; signal-to-noise ratio; Silicone Oils
• ISSN: 1347-3182; 1880-2206
• DOI: 10.2463/mrms.6.177

Purpose: To evaluate the performance advantages of an 8-element phased array head coil (8 ch coil) over a conventional quadrature-type birdcage head coil (QD coil) with regard to the signal-to-noise ratio (SNR) and image uniformity in 3 Tesla magnetic resonance (MR) imaging. Materials and Methods: We scanned a phantom filled with silicon oil using an 8 ch coil and a QD coil in a 3T MR imaging system and compared the SNR and image uniformity obtained from T1-weighted spin echo (SE) images and T2-weighted fast SE images between the 2 coils. We also visually evaluated images from 4 healthy volunteers. Results: The SNR with the 8 ch coil was approximately twice that with the QD coil in the region of interest (ROI), which was set as 75% of the area in the center of the phantom images. With regard to the spatial variation of sensitivity, the SNR with the 8 ch coil was lower at the center of the images than at the periphery, whereas the SNR with the QD coil exhibited an inverse pattern. At the center of the images with the 8 ch coil, the SNR was somewhat lower, and that distribution was relatively flat compared to that in the periphery. Image uniformity varied less with the 8 ch coil than with the QD coil on both imaging sequences. Conclusion: The 8 ch phased array coil was useful for obtaining high quality 3T images because of its higher SNR and improved image uniformity than those obtained with conventional quadrature-type birdcage head coil.