Lowri E. Cochlin1, Kieran Clarke1
1Cardiac Metabolism Research Group,
University of Oxford, Department of Physiology, Anatomy and Genetics, Oxford,
United Kingdom
This
work demonstrates an intuitive approach to weighting data according to
precision achieved during quantification. Cardiac 31P-MRS is used as an
example of data whose accurate fitting is often challenged by low SNR. The
1:1:1 ratio of ::-ATP peaks (excited uniformly with optimized RF-pulse,
NAD and T1 corrected) constitutes three measures of the same molecule.
Probability density functions generated for each integrated peak therefore
combine as a weighted average representing a maximum likelihood estimate of
the true value. Data from 11 healthy volunteers processed probabilistically
demonstrated reduced variance in every PCr/ATP, and reduced inter-subject
PCr/ATP spread, compared to standard weighting.