Personalizing deep brain stimulation using advanced imaging sequences

Abstract Objective With a growing appreciation for interindividual anatomical variability and patient-specific brain connectivity, advanced imaging sequences offer the opportunity to directly visualize anatomical targets for deep brain stimulation (DBS). The lack of quantitative evidence demonstrating their clinical utility, however, has hindered their broad implementation in clinical practice. Methods Using fast gray matter acquisition T1 inversion recovery (FGATIR) sequences, the present study identified a thalamic hypointensity that holds promise as a visual marker in DBS. To validate the clinical utility of the identified hypointensity we retrospectively analyzed 65 patients (26 female, mean age: 69.1±12.7 years) who underwent DBS in the treatment of essential tremor. We characterized its neuroanatomical substrates and evaluated the hypointensity’s ability to predict clinical outcome using stimulation volume modeling and voxel-wise mapping. Finally, we determined whether the hypointensity marker could predict symptom improvement on a patient-specific level. Results Anatomical characterization suggested that the identified hypointensity constituted the terminal part of the dentato-rubro-thalamic tract. Overlap between DBS stimulation volumes and the hypointensity in common space significantly correlated with tremor improvement (R 2 =0.16, p=0.017) and distance to hotspots previously reported in the literature (R 2 =0.49, p=7.9e-4). In contrast, the amount of variance explained by other anatomical atlas structures was reduced. When accounting for interindividual neuroanatomical variability, the predictive power of the hypointensity increased further (R 2 =0.37, p=0.002). Interpretation Our findings introduce and validate a novel imaging-based marker attainable from FGATIR sequences that has the potential to personalize and inform targeting and programming in DBS for essential tremor.