SENSE imaging with a quadrature half‐volume transverse electromagnetic (TEM) coil at 4T

Abstract

Purpose To demonstrate the feasibility of high‐field SENSE imaging of large objects, such as the human head, using a semicircular (half‐volume) coil for both transmission and multi‐channel reception. Materials and Methods As a proof of concept, we present experimental data obtained using a seven‐element half‐volume (180° of arc) transmit/receive quadrature transverse electromagnetic (TEM) coil. SENSE images of the human brain were acquired with a reduction factor of R = 2, using two degenerate linear modes of the same coil as independent receive channels at 4T. Since the need for additional hardware (i.e., a separate set of receive coils) is eliminated, the design can be substantially simplified. Results The experimental data demonstrate that linear modes of the half‐volume TEM coil have essentially no noise correlation, and their sensitivity profiles satisfy the requirement for small g‐factors. Also, this type of coil provides efficient transmission with a relatively large uniform region and a reception profile that is more uniform than that of the surface coils. Conclusion We demonstrate the feasibility of SENSE imaging using a half‐volume coil. Half‐volume coils allow reduced total power deposition compared to full‐volume coils, and may replace the latter in body imaging applications in which the target region of interest (ROI) is smaller than the entire torso. J. Magn. Reson. Imaging 2006.