Probabilistic conversion of neurosurgical DBS electrode coordinates into MNI space

Abstract

In neurosurgical literature, findings such as deep brain stimulation (DBS) electrode positions are conventionally reported in relation to the anterior and posterior commissures of the individual patient (AC/PC coordinates). However, the neuroimaging literature including neuroanatomical atlases, activation patterns, and brain connectivity maps has converged on a different population-based standard (MNI coordinates). Ideally, one could relate these two literatures by directly transforming MRIs from neurosurgical patients into MNI space. However obtaining these patient MRIs can prove difficult or impossible, especially for older studies or those with hundreds of patients. Here, we introduce a methodology for mapping an AC/PC coordinate (such as a DBS electrode position) to MNI space without the need for MRI scans from the patients themselves. We validate our approach using a cohort of DBS patients in which MRIs are available, and test whether several variations on our approach provide added benefit. We then use our approach to convert previously reported DBS electrode coordinates from eight different neurological and psychiatric diseases into MNI space. Finally, we demonstrate the value of such a conversion using the DBS target for essential tremor as an example, relating the site of the active DBS contact to different MNI atlases as well as anatomical and functional connectomes in MNI space.

Connectivity Predicts deep brain stimulation outcome in Parkinson disease

“…The present approach may prove particularly valuable for emerging DBS indications with a limited number of patients implanted at different centers and heterogeneity in clinical response. 2,4,24,37 Such DBS datasets may be analyzed retrospectively even if no individual connectivity data were acquired.…”

Automatic localization of the subthalamic nucleus on patient‐specific clinical MRI by incorporating 7 T MRI and machine learning: Application in deep brain stimulation

“…Standard atlases that are well defined in a normalized space could be of great value for retrospective population studies and are highly appreciated in the field (Horn, Kühn, et al, 2017; Horn, Neumann, et al, 2017; Horn, Reich, et al, 2017; Keuken et al, 2014). However, uncertainty in registration needs to be addressed when using such atlases for patient-specific STN-DBS targeting.…”

“…Postoperative active contacts’ clusters projected onto the CranialVault atlas were used for DBS target prediction in Pallavaram et al (2015). A probabilistic approach to map DBS electrode coordinates onto the MNI space was presented in Horn, Kühn, et al (2017). More recently, to achieve anatomical precision in the MNI space, a histological atlas (Chakravarty, Bertrand, Hodge, Sadikot, & Collins, 2006) was merged with subcortical atlases based on multiple contrast 3 T MR sequences from PD patients (Xiao et al, 2017) and high resolution multimodal MRIs and structural connectivity data (Ewert et al, 2017).…”

A localized pallidal physiomarker in cervical dystonia

“…29,30 The trajectory span on the ventrodorsal z-axis was 212.4 mm to 1 0.2 mm, whereas the internal pallidum spans from 28 mm to1 0.5 mm. 29,30 The trajectory span on the ventrodorsal z-axis was 212.4 mm to 1 0.2 mm, whereas the internal pallidum spans from 28 mm to1 0.5 mm.…”

“…a Converted to Montreal National Institute coordinates in Horn et al 30 DBS 5 deep brain stimulation; GPi 5 globus pallidus internus. Distance between recording sites and each of these coordinates was correlated with theta power recorded at the site (last column) to reveal a systematic distribution of theta power in the spatial domain and a relationship between theta power and the optimal DBS stimulation site.…”