Figure 3.
Foundations of RSI – Geometric Filtering; (A) schematic outlining the basic parameters of the RSI multishell acquisition, with opposed phase encoding gradients in the b = 0 acquisition used for distortion correction and 6, 6, and 15 non-parallel gradients for the non-zero b values. (B) Using this data, RSI can simultaneously acquire length-scale distribution data and geometric information, allowing isolation of isotropic and anisotropic orientation data. In prostate cancer, RSI is used to isolate signal from highly restricted and isotropic water.