MRI-Based Quantification of Magnetic Susceptibility in Gel Phantoms: Assessment of Measurement and Calculation Accuracy

Figure 2

(a) Phase image and (b) the corresponding calculated susceptibility image of the phantom with varying angles of the cylinders (slice 17 of 48). The graphs in (c) and (d) show theoretical as well as experimental phase and susceptibility in the cylinders as a function of the angle relative to the main magnetic field. (c) Analytically calculated phase values (based on the infinite-cylinder approximation and the reference values in Table 1) and the corresponding measured phase values. (d) Expected theoretical magnetic susceptibility values (based on the reference values in Table 1) as well as the estimates based on experimental phase data, i.e., employing the infinite-cylinder approximation as well as the QSM algorithm. Error bars correspond to the standard deviation within the region of interest for the experimental QSM data.

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