Achieving 1 ppm field homogeneity above 24 T: Application of differential mapping for shimming Keck and the Series Connected Hybrid magnets at the NHMFL.

Powered resistive and resistive-superconductive hybrid magnets can reach fields higher than superconducting NMR magnets but lack the field homogeneity and temporal stability needed for high resolution NMR. Due to field fluctuations in powered magnets, commercially available mapping systems fail to produce maps of these magnets with sufficient reproducibility, thus hampering attempts to improve homogeneity of the field they generate. Starting with a commercial mapper, we built a mapping system which uses a two-channel (measurement + reference) mapper probe. We used this system to map and then to shim two magnets of Florida Bitter type at the National High Magnetic Field Laboratory in Tallahassee, FL. With a combination of passive (ferromagnetic) and active shims we achieved 2.3 ppm homogeneity in 1 cm diameter spherical volume (dsv) at 25.0 T in the Keck resistive magnet, and 0.9 ppm homogeneity in 1 cm dsv at 23.5, 28.2, and 35.2 T in the series-connected resistive-superconductive hybrid (SCH) magnet.

Targeting improved patient outcomes using innovative product listing agreements: a survey of Canadian and international key opinion leaders.

OBJECTIVES: To address the uncertainty associated with procuring pharmaceutical products, product listing agreements (PLAs) are increasingly being used to support responsible funding decisions in Canada and elsewhere. These agreements typically involve financial-based rebating initiatives or, less frequently, outcome-based contracts. A qualitative survey was conducted to improve the understanding of outcome-based and more innovative PLAs (IPLAs) based on input from Canadian and international key opinion leaders in the areas of drug manufacturing and reimbursement. METHODS: Results from a structured literature review were used to inform survey development. Potential participants were invited via email to partake in the survey, which was conducted over phone or in person. Responses were compiled anonymously for review and reporting. RESULTS: Twenty-one individuals participated in the survey, including health technology assessment (HTA) key opinion leaders (38%), pharmaceutical industry chief executive officers/vice presidents (29%), ex-payers (19%), and current payers/drug plan managers/HTA (14%). The participants suggested that ~80%-95% of Canadian PLAs are financial-based rather than outcomes-based. They indicated that IPLAs offer important benefits to patients, payers, and manufacturers; however, several challenges limit their use (eg, administrative burden, lack of agreed-upon endpoint). They noted that IPLAs are useful in rapidly evolving therapeutic areas and those associated with high unmet need, a quantifiable endpoint, and/or robust data systems. The Canadian Agency for Drugs and Technologies in Health, the pan-Canadian Pharmaceutical Alliance, and other arms-length organizations could play important roles in identifying uncertainty and endpoints and brokering pan-Canadian PLAs. Industry should work collaboratively with payers to identify uncertainty and develop innovative mechanisms to address it. CONCLUSION: The survey results indicated that while challenging, use of IPLAs may be associated with various benefits. Collaboration among stakeholders remains key: Canadian agencies could play an important role in the success of these agreements, while industry should be proactive in offering solutions that will help improve outcomes across the entire health care system.