A 16-channel receive, forced current excitation dual-transmit coil for breast imaging at 7T

• Published in: PloS one 2014-11, Vol.9 (11), p.e113969-e113969
• Main Authors: By, Samantha, Rispoli, Joseph V, Cheshkov, Sergey, Dimitrov, Ivan, Cui, Jiaming, Seiler, Stephen, Goudreau, Sally, Malloy, Craig, Wright, Steven M, McDougall, Mary Preston
• Format: Article
• Language: English
• Subjects: Biology and Life Sciences; Biomedical engineering; Breast; Breast - anatomy & histology; Breast Neoplasms - diagnosis; Breast Neoplasms - prevention & control; Coiling; Comparative analysis; Computer engineering; Design; Diagnostic imaging; Engineering and Technology; Equipment Design; Excitation; Feasibility studies; Female; Humans; Image acquisition; Image resolution; Magnetic resonance imaging; Magnetic Resonance Imaging - instrumentation; Magnetic Resonance Imaging - methods; Mammography; Medicine and Health Sciences; NMR; Noise; Nuclear magnetic resonance; Phantoms, Imaging; Reproducibility of Results; Research and Analysis Methods; Signal-To-Noise Ratio; Spatial discrimination; Spatial resolution; Spectrum analysis; Temporal resolution
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0113969

To enable high spatial and temporal breast imaging resolution via combined use of high field MRI, array coils, and forced current excitation (FCE) multi channel transmit. A unilateral 16-channel receive array insert was designed for use in a transmit volume coil optimized for quadrature operation with dual-transmit RF shimming at 7 T. Signal-to-noise ratio (SNR) maps, g-factor maps, and high spatial and temporal resolution in vivo images were acquired to demonstrate the utility of the coil architecture. The dual-transmit FCE coil provided homogeneous excitation and the array provided an increase in average SNR of 3.3 times (max 10.8, min 1.5) compared to the volume coil in transmit/receive mode. High resolution accelerated in vivo breast imaging demonstrated the ability to achieve isotropic spatial resolution of 0.5 mm within clinically relevant 90 s scan times, as well as the ability to perform 1.0 mm isotropic resolution imaging, 7 s per dynamics, with the use of bidirectional SENSE acceleration of up to R = 9. The FCE design of the transmit coil easily accommodates the addition of a sixteen channel array coil. The improved spatial and temporal resolution provided by the high-field array coil with FCE dual-channel transmit will ultimately be beneficial in lesion detection and characterization.