Design and development of a planar B0‐coil for patient respiratory motion correction in magnetic resonance imaging

Abstract

AbstractWe detail the design, construction, and testing of a planar B0‐coil which will ultimately be used to reduce artifacts in magnetic resonance imaging (MRI) caused by respiratory motion in patients. The B0‐coil combined with a micro‐electro‐mechanical system microcoil detector mounted on a catheter and deployed in an endoscope should in‐principle enable sub‐millimeter resolution MR imaging of cholangiocarcinomas. The B0‐coil has been designed to generate around 300 μT of magnetic field, parallel to the main field of a MRI scanner, and to be homogenous to around 1% in a 150 mm diameter of spherical volume (DSV). Measurements of the field in the DSV reveal that there are no field gradients present (within our experimental resolution of 3 μT) in the region and the field is homogeneous with a mean value of 324.5 ± 4.3 μT (1σ) at 25 A. The B0‐coil was subsequently deployed in MRI experiments on a test phantom to confirm axial and sagittal image slice shifts of ∼ 12 and 3 mm, respectively, using only 5.5 A in the B0‐coil. This clearly demonstrates the principle of image slice shifting by modulating the main field of a MRI magnet using a relatively small field generated in an insert coil. © 2012 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 41B: 130–138, 2012