Wang, Paul2021-10-252021-10-252021-08https://hdl.handle.net/11299/225125University of Minnesota Ph.D. dissertation. August 2021. Major: Biomedical Engineering. Advisor: Michael Garwood. 1 computer file (PDF); xi, 139 pages.Islet macroencapsulation within an immunoisolation membrane is emerging as a promising new treatment for diabetes, yet providing adequate oxygenation to transplanted, encapsulated islets remains a major challenge because: 1) the islets require a specific level of oxygen (pO2) - both too little and too much oxygen impairs islet functionality and viability; 2) it is challenging to make in vivo oxygen measurements non-invasively. This thesis describes progress towards the development of a proto-type low-cost, portable, gradientless desktop MR oxygen scanner that can be used, in conjunction with an oxygen sensitive MR probe such as perfluoro-15-crown-5-ether (PFCE), to make non-invasive oxygen measurements in islet macroencapsulation devices in vivo. Novel methods are also described to accelerate oxygen measurement speed as well as to perform imaging and field mapping without using standard B0 gradients. The vision for this scanner, which is specifically designed for making pO2 measurements in macroencapsulation devices, is that one day it will be deployed in local pharmacies and supermarkets across the country, to meet the need that people with diabetes, who have received an islet macrencapsulation device implant, will have to get their oxygen measured and tuned for optimal transplant function.enB1 encodingdesktop MRIdesktop oxygen scannerislet macroencapsulationportable MRIThesis or Dissertation