Harmonic Field Extension for QSM with Reduced Spatial Coverage using Physics-informed Generative Adversarial Network

Acquisition of whole brain Quantitative Susceptibility Mapping (QSM) is time-consuming that requires the patient’s effort. On the other hand, limiting the QSM field-of-view to only the region of interest (e.g., deep grey matter) can shorten scan time and lessen the patient’s burden. However, reducing spatial coverage degrades conventional background field removal performance, resulting in an underestimation of susceptibility values. To overcome these limitations, we propose a harmonic field extension method using a physics-informed generative adversarial network. According to the experimental results, the proposed method significantly improves the accuracy of both the local field and QSM at reduced spatial coverage.