There is an established clinical need for a non-invasive measure of body iron stores that is safe, accurate, cost effective and readily available. An accurate, clinically validated susceptometer based on low-temperature superconductivity (LTS) has been available for more than two decades, but its complexity, cost (~$1,000,000), and need for liquid helium have restricted its use to a handful of research centers. Given the liquid helium requirement, and the fact that no significant cost reduction has occurred since its inception, it has been widely felt that superconducting susceptometry is unlikely to enter general clinical practice. The discovery of high-Tc superconductivity and the recent emergence of flexible materials based employing superconductors have dramatically altered the technical picture. In Phase I, we combined these novel materials with a number of other recent advances and overcame the technical barriers to widespread implementation noted. Specifically, we developed an proof-of-principle instrument using conventional magnetic sensors and a very innovative flux concentrator. The recent availability of low vibration and small mass cryocoolers has made the instrument depend only on wall power for operation and uncomplicated cryogenics. The new proposed instrument will have a material parts cost often times less than the ITS system and be much simpler to operate and maintain. A new measurement methodology has been developed that eliminates the costlier and unreliable elements while promising equivalent or superior sensitivities. Our Phase II goal is to build on our strong progress in Phase I and construct a prototype cryosusceptometer that is accurate, inexpensive and can be operated by personnel who have no specialized technical training. A simple low-cost cryosusceptometer will satisfy the pressing need for accurate clinical iron assessment over a wide range of iron stores (0.2 mg/g-wet weight to above 10 mg/g). It also promises to open up a number of other applications for superconducting susceptometry, in both medicine and industry. To achieve this, we propose a step-by-step development program that concludes with a preliminary clinical evaluation involving twenty iron overloaded (thalassemic and sickle-cell) patients and five normal control subjects. ? ?
