Estimation of the Angle Between Crossing Fibers as a Novel Structural Quantity

Ofer Pasternak¹, Yogesh Rathi¹, Martha Shenton¹, Carl-Fredrik Westin¹

We present a method to extract crossing-angle maps from HARDI analysis. Applying the method on first-episode schizophrenia patients demonstrates a significant group-difference comparing with matched controls. In addition, we demonstrate that FA is not sensitive to the crossing-angle. Based on these findings we suggest the crossing-angle as a novel structural marker sensitive to unique HARDI information. The crossing-angle is expected to be influenced by large brain deformations such as tumors and sever trauma. However, in the absence of such major confounds we expect crossing-angle abnormalities to reflect developmental differences or local cytoskeletal dysfunction that changed the configuration of the crossings.