Sensitivity of an eight-element phased array coil in 3 Tesla MR imaging: a basic analysis.
OBJECTIVE
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.


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 T(1)-weighted spin echo (SE) images and T(2)-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.


CONCLUSIONS
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.
Department of Radiology, Ehime University School of Medicine, Ehime, Japan. hirazka@m.ehime-u.ac.jp
Yoshiyasu
Y
Hiratsuka
Hitoshi
H
Miki
Keiichi
K
Kikuchi
Ikuko
I
Kiriyama
Teruhito
T
Mochizuki
Shizue
S
Takahashi
Kazuhiko
K
Sadamoto
D000328:Adult; D016477:Artifacts; D001921:Brain / Q000033:anatomy & histology; D002555:Cerebrospinal Fluid; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation / Q000379:methods / Q000592:standards; D007091:Image Processing, Computer-Assisted / Q000379:methods / Q000592:standards; D020547:Lateral Ventricles / Q000033:anatomy & histology; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods / Q000592:standards; D008297:Male; D019047:Phantoms, Imaging; D012827:Silicone Oils
D012827:Silicone Oils