Impact of brain shift on subcallosal cingulate deep brain stimulation

• Published in: Brain stimulation Vol. 11; no. 2; pp. 445 - 453
• Main Authors: Choi, Ki Sueng, Noecker, Angela M., Riva-Posse, Patricio, Rajendra, Justin K., Gross, Robert E., Mayberg, Helen S., McIntyre, Cameron C.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.03.2018
• Subjects: Adult; Aged; Brain - diagnostic imaging; Brain - physiopathology; Connectomic; Deep Brain Stimulation - methods; Depressive Disorder, Treatment-Resistant - diagnostic imaging; Depressive Disorder, Treatment-Resistant - therapy; Diffusion Tensor Imaging; Electrode; Electrodes, Implanted; Female; Humans; Male; Middle Aged; Neurosurgery; Stereotactic; Tractography; Electrode; Neurosurgery; Connectomic; Tractography; Stereotactic
• ISSN: 1935-861X; 1876-4754
• DOI: 10.1016/j.brs.2017.12.001

Deep brain stimulation (DBS) of the subcallosal cingulate (SCC) is an emerging experimental therapy for treatment-resistant depression. New developments in SCC DBS surgical targeting are focused on identifying specific axonal pathways for stimulation that are estimated from preoperatively collected diffusion-weighted imaging (DWI) data. However, brain shift induced by opening burr holes in the skull may alter the position of the target pathways. Quantify the effect of electrode location deviations on tractographic representations for stimulating the target pathways using longitudinal clinical imaging datasets. Preoperative MRI and DWI data (planned) were coregistered with postoperative MRI (1 day, near-term) and CT (3 weeks, long-term) data. Brain shift was measured with anatomical control points. Electrode models corresponding to the planned, near-term, and long-term locations were defined in each hemisphere of 15 patients. Tractography analyses were performed using estimated stimulation volumes as seeds centered on the different electrode positions. Mean brain shift of 2.2 mm was observed in the near-term for the frontal pole, which resolved in the long-term. However, electrode displacements from the planned stereotactic target location were observed in the anterior-superior direction in both the near-term (mean left electrode shift: 0.43 mm, mean right electrode shift: 0.99 mm) and long-term (mean left electrode shift: 1.02 mm, mean right electrode shift: 1.47 mm). DBS electrodes implanted in the right hemisphere (second-side operated) were more displaced from the plan than those in the left hemisphere. These displacements resulted in 3.6% decrease in pathway activation between the electrode and the ventral striatum, but 2.7% increase in the frontal pole connection, compared to the plan. Remitters from six-month chronic stimulation had less variance in pathway activation patterns than the non-remitters. Brain shift is an important concern for SCC DBS surgical targeting and can impact connectomic analyses. •Connectomic deep brain stimulation surgical targeting represents a promising new strategy.•Intraoperative brain shift can alter the location of a tractography defined surgical target.•Remitters from SCC DBS had less variance in activation patterns than the non-remitters.