Using probabilistic tractography to target the subcallosal cingulate cortex in patients with treatment resistant depression.

The lack of efficacy of deep brain stimulation (DBS) of subcallosal cingulate (SCC) in treatment resistant depression (TRD) may be due in part to suboptimal targeting. In two patients treated with SCC DBS for TRD we assessed the voxel-wise probabilistic connectivity of SCC with four tractography-defined target areas implicated in depression, thereby identifying the tractography-optimized target (TOT). Compared to the non-responder, the responder's DBS leads were implanted and stimulation was delivered closer to the TOT. This automated patient-specific data-driven approach provides tomographic maps that could guide DBS targeting and programming with possible implications for improving response to DBS.