Best precision in measuring Qp/Qs is achieved with quadratic, not linear, stationary tissue background correction in phase contrast velocity encoded CMR

Background Cardiovascular magnetic resonance (CMR) flow quantification for determining the ratio of flow between the pulmonary artery and aorta (Qp/Qs) is used to quantify cardiac shunts. Post-processing methods, including linear or quadratic stationary tissue background correction have been proposed to improve accuracy and precision in flow quantification. However, it is not known which method improves the flow quantification the most, and if patient characteristics effect the correction. We evaluated changes in accuracy and precision of Qp/Qs following both linear and quadratic stationary tissue background correction, and investigated the effect on the precision of different patient characteristics. We hypothesized that the standard deviation of mean Qp/Qs would be reduced following stationary background correction compared to uncorrected measures.