Fig. 4.

Unique patterns of pre-surgical diffusivity alterations distinguish responders from non-responders.

Key pre-surgical DTI metric patterns differentiating long-term responders from non-responders along symptomatic trigeminal nerves are shown. Long-term responders (in blue) have unique microstructural abnormalities localized to the trigeminal nerve cisternal segment (CS) whereas non-responders (in red) have abnormalities located more centrally—at the root entry zone (REZ) and pontine segment (PS) of the nerve. The illustration on the right is a sagittal view of the brainstem. Yellow-orange dots in this view illustrate these key regions of interest from which DTI metrics were gathered.