Daily Longitudinal Quality Assessment in MRI: From Short-Term Fluctuations to Long-Term Stability

Peter Brunecker¹, Claudia Kunze¹, Anja Grebe¹, Chao Xu¹, Ivana Galinovic¹, Jochen B. Fiebach¹

Monitoring of long-term alterations in MRI scanner parameters is essential for observational studies extending over several years. However, during this time intentional adjustments of the scanner hardware can actively introduce changes on a mid-term scale. To investigate this, daily phantom measurements were performed over a time period of 20 months and mean signal magnitude, signal-to-noise ratio, and uniformity were estimated. We found that sudden alterations of the absolute signal magnitude in our data were triggered by technical maintenance. We suggest that using a correction based on the stepwise constant behavior of scanner hardware parameters in time could prevent such alterations.