Though it is now the diagnostic tool of choice in a wide range of clinical situations, the actual usage of MRI is limited by its expense even in relatively prosperous communities. High-field MRI capital equipment costs range upward from approximately $1,000,000. Installation and operating costs are also high. MRI signals are stronger, and the resulting images have better spatial resolution, at higher magnetic fields. Unfortunately, higher-field MRI instruments are more expensive to build, install, and operate. High spatial resolution is not always necessary, however, and low-field MRI can provide better contrast between dissimilar tissues. We propose a fundamentally new technique for magnetic imaging at low fields, and a new approach to the design of the electronics package, yielding better sensitivity than conventional low-field MRI combined with dramatically lowered costs. Installation and infrastructure requirements would also be reduced. Such a system has the potential for extending the health benefits of MRI to those who are simply not able to afford the cost of using a conventional system, currently most of the world's population. Since the U.S. is a leader in MRI production, the commercial value of expanding the MRI market into the less-developed countries of the world would also be substantial.
