Poster D79, Monday, March 26, 8:00-10:00 am, Exhibit Hall C
Presurgical fMRI for Aiding Electrode Implantation in Deep Brain Stimulation: Case studies of Treatment-Resistant Depression
Layla Gould1, Ivar Mendez1, Chelsea Ekstrand1, Marla Mickleborough1, Tasha Ellchuk1, Eric Lorentz1, Ron Borowsky1; 1University of Saskatchewan
Functional magnetic resonance imaging (fMRI) is becoming increasingly common in presurgical planning as it allows for noninvasive localization of function in order to inform neurosurgeons as they devise a surgical approach. Moreover, fMRI can be used to localize the target nucleus in deep brain stimulation (DBS). We report two cases of patients undergoing DBS for treatment-resistant depression, in which the neurosurgeon was targeting the subgenual anterior cingulate cortex (ACC; Brodmann Area 25). Previous research has shown that different versions of Stroop-like interference tasks activated dichotomous regions of the ACC, whereby a cognitive version activated the superior subdivision of the ACC, whereas an emotional/affective version activated the inferior subdivision (Bush, Luu, & Posner, 2000). Thus, our planning involved two Stroop-like interference tasks, namely, one cognitive (i.e., Stroop task with color words) and one affective (i.e., Stroop task with emotional words). All imaging was conducted using a 3T Siemens Skyra scanner. All preprocessing and statistical analyses for functional images were performed using Brain Voyager QX. In both cases, the fMRI results for the affective Stroop task showed deactivation in the subgenual ACC as predicted, and this helped guide the placement of the electrodes for the DBS procedure. These case studies confirm that cognitive and affective tasks selectively activate different regions of ACC, and highlight the utility of preoperative planning using fMRI for patients being treated with DBS for depression.
Topic Area: METHODS: Neuroimaging