Detunable transverse electromagnetic (TEM) volume coil for high‐field NMR

Most high‐field MRI systems do not have the actively detuned body coils that are integral to clinical systems operating at 1.5T and lower field strengths. Therefore, many clinical applications requiring homogeneous volume excitation in combination with local surface coil reception are not easily implemented at high fields. To solve this problem for neuroimaging applications, actively detunable transverse electromagnetic (TEM) head coils were developed to be used with receive‐only surface coils for signal‐to‐noise ratio (SNR) gains and improved spatial coverage from homogeneously excited regions. These SNR and field of view (FOV) gains were achieved by application of a detunable TEM volume coil to human brain imaging at 4T. Magn Reson Med 47:990–1000, 2002. © 2002 Wiley‐Liss, Inc.

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