UROP Project

Design and Construction of B0 Multi-Coil Hardware for the World's First Portable 1.5T MRI Head Scanner

Spatial encoding in magnetic resonance imaging (MRI) is typically achieved by linear magnetic field gradients that are generated by dedicated wire patterns with one coil per gradient orientation. My colleagues and I demonstrated that a set of simple, localized coils can be converted to a powerful magnetic field modeling system when the electrical coils are driven individually (1). The superposition of these multi-coil (MC) basis fields allows the synthesis of a large variety of simple and complex magnetic field shapes. The method is ideally suited to homogenize magnetic fields (so-called "B0 shimming") (2,3), but can also be used to generate spatial encoding fields for MRI. As such, we recently demonstrated that MRI with radial encoding is possible with MC-generated magnetic field gradients ((4), my first UROP project). We subsequently demonstrated that virtually all modern MRI sequences can be realized with MC technology, i.e. without the use of conventional gradient coils. Moreover, we were able to show that the MC approach allows concurrent spatial encoding (i.e. MRI) and B0 shimming with the same setup ((5), the second UROP project I supervised). After first MC implementations for MRI in miniaturized setups (a few centimeters in size), here we are setting out to develop, construct and implement MC technology for MRI of the human head (6). The research at hand is part of a 5-year federally funded multi-center project that aims to establish the world's first head-only 1.5 Tesla MRI scanner.

Task

The theoretical MC design includes the analysis of ist B0 field shaping capability for MRI, temperature management, minimization of electromagnetic interactions and the analysis of mechanical properties under the influence of the apparent forces. You will be involved in all aspects of the theoretical analysis as well as the benchtop validation experiments and the construction of the derived setup. Prior machine shop experience such as milling, soldering, or working with epoxy resin is not mandatory, but helpful. In addition, you will learn about the main MRI methods currently used in biomedical research, the concepts of MRI sequence coding along with MRI post-processing and reconstruction techniques. The work will comprise all aspects of an MRI experiment and will allow you to experience various aspects of MR research ranging from the theoretical design of MC technology to the hands-on implementation and application of the developed technology. 1. Juchem C, Nixon TW, McIntyre S, Rothman DL, de Graaf RA. Magnetic field modeling with a set of individual localized coils. J Magn Reson 2010;204(2):281-289. 2. Juchem C, Brown PB, Nixon TW, McIntyre S, Rothman DL, de Graaf RA. Multi- coil shimming of the mouse brain. Magn Reson Med 2011;66(3):893-900. 3. Juchem C, Nixon TW, McIntyre S, Boer VO, Rothman DL, de Graaf RA. Dynamic multi-coil shimming of the human brain at 7 Tesla. J Magn Reson 2011;212:280-288. 4. Juchem C, Nahhass OM, Nixon TW, de Graaf RA. Multi-slice MRI with the dynamic multi-coil technique. NMR Biomed 2015;28(11):1526-1534. 5. Rudrapatna SU, Fluerenbrock F, Nixon WT, de Graaf RA, Juchem C. Combined Imaging and Shimming with the Dynamic Multi-Coil Technique. Magn Reson Med (in press). 6. Theilenberg S, Shang Y, Tirumala SS, Juchem C. Development of Multi-Coil B0 Technology with Computer-Aided Design Software. Proc ISMRM. Paris, France; 2018. p. 4316.

Requirements

Basic knowledge of magnetic resonance imaging (MRI) will be helpful

Full Address

Columbia University
New York City, NY
USA