Diffusion Tensor Imaging-Based Thalamic Segmentation in Deep Brain Stimulation for Chronic Pain Conditions

Abstract

Background/Aims: Thalamic deep brain stimulation (DBS) for the treatment of medically refractory pain has largely been abandoned on account of its inconsistent and oftentimes poor efficacy. Our aim here was to use diffusion tensor imaging (DTI)-based segmentation to assess the internal thalamic nuclei of patients who have undergone thalamic DBS for intractable pain and retrospectively correlate lead position with clinical outcome. Methods: DTI-based segmentation was performed on 5 patients who underwent sensory thalamus DBS for chronic pain. Postoperative computed tomography images obtained for electrode placement were fused with preoperative magnetic resonance images that had undergone DTI-based thalamic segmentation. Sensory thalamus maps of 4 patients were analyzed for lead positioning and interpatient variability. Results: Four patients who experienced significant pain relief following DBS demonstrated contact positions within the DTI-determined sensory thalamus or in its vicinity, whereas 1 patient who did not respond to stimulation did not. Only 4 voxels (2%) within the sensory thalamus were mutually shared among patients; 108 voxels (58%) were uniquely represented. Conclusions: DTI-based segmentation of the thalamus can be used to confirm thalamic lead placement relative to the sensory thalamus and may serve as a useful tool to guide thalamic DBS electrode implantation in the future.

The potential value of probabilistic tractography-based for MR-guided focused ultrasound thalamotomy for essential tremor

“…In previous studies, probabilistic and deterministic approaches were used for thalamic targeting in ET patients ( Pouratian et al, 2011 , Kim et al, 2016 , Hyam et al, 2012 , Kincses et al, 2012 , Sedrak et al, 2011 ). Pouratian et al (2011) reported a new method of targeting patient-specific therapeutic thalamic target for the treatment of tremor based on individualized probabilistic tractography analysis of thalamic connectivity patterns to premotor and supplementary motor cortices.…”

“… Pouratian et al (2011) reported a new method of targeting patient-specific therapeutic thalamic target for the treatment of tremor based on individualized probabilistic tractography analysis of thalamic connectivity patterns to premotor and supplementary motor cortices. The same approach ( Kim et al, 2016 ) was validated for the definition of Vim in a tremor-dominant Parkinson's disease patient. Others have used probabilistic tractography to explore the individual thalamic nuclei connectivity profiles and to reveal the inter-individual variability of the anatomical position of nuclei areas ( Hyam et al, 2012 , Kincses et al, 2012 ).…”

Improving Surgical Outcome Using Diffusion Tensor Imaging Techniques in Deep Brain Stimulation

“…Periventricular gray/PAG was targeted in eight patients (six responders), among whom four also received simultaneous stimulation in the ventroposterolateral and ventroposteromedial nuclei (VPL/VPM) ( 47 , 49 , 50 ). Those with suboptimal outcomes (one non-responder and one responder who subsequently failed) had electrodes which were found to be too medial to the VPL/VPM region ( 47 ).…”

Advanced Imaging and Direct Targeting of the Motor Thalamus and Dentato-Rubro-Thalamic Tract for Tremor: A Systematic Review

“…This review focuses specifically on the motor thalamus and DRTT; however, some of the techniques described can be applied to parcellate other functional and anatomic regions of the thalamus, including the anterior nuclear group in the treatment of epilepsy and limbic system disorders [34], specific sensory [35-38], and relay nuclei [39-41] and nuclei implicated in multiple sclerosis [42, 43], depression [44], Alzheimer’s disease [45], and Parkinson’s disease (PD) [46]. If these methods prove reliable, they may provide valuable opportunities to study pathophysiology in vivo by evaluating volumetric (and, possibly, functional) changes in specific nuclei in a variety of neurodegenerative and psychiatric disorders [47].…”