Performance Assessment of Phased-Array Coil in Breast MR Imaging

Abstract

Purpose: To compare the performance of the phased-array coil (PAC) with that of the single-loop coil (SLC) in magnetic resonance (MR) imaging of the breast.Materials and Methods: MR imaging was performed with a 1.5T MR imager. A phantom study was performed with the right element of the two coils to obtain their signalto-noise ratio (SNR). MR images of the breasts of 12 patients with breast lesions were obtained with the PAC and SLC, and these images were reviewed byˆve readers in a blind evaluation employing a scoring system for assessing overall image quality.Results: In the phantom study, the SLC exhibited a SNR 1.82 times higher than that of the PAC at the center of the coil; however, the SLC exhibited an inhomogeneous sensitivity proˆle and its SNR varied with the distance from the center of the coil in the horizontal and vertical directions. In most of the 12 patients, the MR images obtained with the PAC showed more noise than did those obtained with the SLC, and the PAC obtained lower scores than the SLC in the assessment of overall image quality; however, the diŠerence was signiˆcant (pº0.05) only in coronal imaging. On the other hand, the uniformity of fat saturation in the MR images obtained with the PAC was judged to be signiˆcantly superior to that obtained with the SLC (pº0.05).Conclusion: Compared with the SLC, the PAC exhibited a lower SNR and was less advantageous at depicting the breast. However, the PAC provided more homogeneous fat saturation and might be useful for reducing artifacts.

Growth trajectories and cluster features of the human fetal brain estimated by signal intensity from sBTFE sequence in utero MRI

“…Abdominal imaging using phased-array coils is known to suffer from spatially inhomogeneous signal sensitivity profile (both excitation and reception profile) [12]. To avoid the heterogeneity from variations in the coil sensitivities, all pregnant women lied supine in the scanner making the orientation of sequence consistent across women; second, considering heterogeneity from variations in the coil sensitivities, the technique of constant level appearance (CLEAR) [13] was used as homogeneity correction, using a scaled signal intensities corresponding to the use of a uniformly sensitive coil (like the Q-Body coil).…”

MR breast imaging : a comparative analysis of conventional and parallel imaging acquisition

“…Unfortunately, these two criteria are competing demands, and new MRI strategies are required to reconcile these two divergent necessities [9]. Developments have been made in surface coil technology, resulting in improved spatial resolution and imaging protocols and reduced acquisition time [10]. The latest development in MRI is parallel imaging, a group of techniques that take advantage of the spatial information inherent in phased-array radiofrequency coils.…”

“…Tuttavia risoluzione spaziale e temporale sono in conflitto e nuove strategie RM sono necessarie al fine di ottimizzare i protocolli RM [9]. Recentemente, sono stati compiuti numerosi progressi nella tecnologia delle bobine di superficie che hanno portato allo sviluppo di nuovi e più efficaci protocolli d'acquisizione con un conseguente incremento della risoluzione spaziale ed una riduzione dei tempi di acquisizione [10]. Il più recente sviluppo tecnologico per la riduwas to compare conventional breast MRI and breast MRI acquired with the SENSE technique on a 1.5 T scanner in the same patients, on the basis of image quality and kinetics analysis.…”