SNR and Discretization Enhancement for System Matrix Determination by Decreasing the Gradient in Magnetic Particle Imaging

In system matrix (SM) based reconstruction, the physical resolution is often within the range of the SM discretization. This is caused by the signal to noise ratio (SNR) decrease following a discretization increase due to the smaller particle sample volume. As the SNR affects the resolution of the image as well, it is necessary to decouple the SNR and discretization. In this work, a calibration protocol is presented which enhances either the SNR or discretization by reducing the gradient strength within the system calibration. This new protocol results in higher resolution and better image quality.