Dear friends of Lead-DBS,
A short question up front:
We are applying for a grant to further support Lead-DBS development. If Lead-DBS helps you in your scientific work, you like the project or just the idea about it, please consider writing a short Letter of Support for us. All info and a template can be found here.
Then, Ningfei just uploaded a new version of Lead-DBS which comes with some nice new datasets that I wish to highlight in the following:
Electrophysiological Atlas of GPi Activity (Neumann 2017)
In a new study spearheaded by Julian Neumann (Kühn lab), we were able to relate pallidal theta power to dystonic symptom severity for the first time. Furthermore, using the "Subcortical Electrophysiology Mapping (SEM)" approach developed as part of Lead-DBS, we were able to robustly localize theta activity to an anatomical subpart of the internal pallidum that most likely corresponds to its sensorimotor functional zone.
The same approach had been used before to localize beta power in PD within the subthalamic nucleus.
I described the approach in detail in a blog post and the Lead-DBS knowledge base and we hope that other groups may use it to map electrophysiology to anatomy, in the future.
Moreover, one result of both studies was to create "electrophysiology atlases" that are now available in Lead-DBS (the Parkinson-based "Beta atlas" has already been available for some time). In case of the "pallidal theta atlas" for dystonia, we included several optimal "sweet spots" for pallidal stimulation that had been described in the literature as well as our probabilistic theta power mapping. Finally, we again included the pallidal parcellation performed by Siobhan Ewert in the DISTAL atlas study.
In sum, I am excited that this new atlas may truly give some aggregated and conclusive evidence for an optimal stimulation target in Dystonia. Needless to say, we're eager to hear your thoughts about it.
Novel "Electrophysiological Atlas of GPi Activity (Neumann 2017)" included in Lead-DBS
CIT168 atlas (Pauli 2017)
Originally built in the context of Reinforcement Learning, Wolfgang Pauli and colleagues from Caltech have created a stunningly precise brain template with a beautiful subcortical atlas that comprises exactly the structures we usually target in DBS. The authors graciously agreed to include their atlas inside Lead-DBS. It was not created in MNI space but in a novel "CIT168" space that comes with a T1- and T2-template. Thus, I added this space + atlas to the Lead-DBS "spaces" feature and also included an MNI-imported version of the atlas. So two options to use it: i) Switch to CIT168 space from the "Spaces" menu and normalize patients into this novel space to analyze them with the novel atlas. ii) use the imported MNI version of the CIT168 space taking into account slight inaccuracies (see first figure on this page for description of a similar problem).
New Brain parcellations for connectivity analyses
To perform connectivity analyses, we added a few novel brain parcellations, including the HMAT (Mayka 2005), the S_MATT (Archer 2017) as well as the great new Schäfer 2017 whole brain parcellations that base on the famous Yeo 2011 7/17 rs-fMRI parcellation and further subdivide these networks.
Human Motor Area Template (Mayka 2005)
Sensorimotor Area Tract Template (Archer 2017)
Schaefer 2017 Brain parcellations
We hope that you like the new ressources added to Lead-DBS v.220.127.116.11 and we'll be back with some cool new features, hopefully, very soon, too!
Once again, if you can afford the time, please consider writing a Letter of Support for our upcoming grant publication.
Best regards on behalf of all contributors,