Localization of Brain SubThalamic Nucleus using Joint Diffusion MRI-Functional MRI Analysis for Parkinson Patients: Application to Deep Brain Stimulation
(TÜBİTAK 1001, 2015 - 2017)
In scenarios where medication, which is the primary treatment approach to neurological functional disorders such as Parkinson, dystonia, epilepsy, obsessive compulsive disorder (OCD), major depression and trigeminal neuralgia, is ineffective, Deep Brain Stimulation (DBS) is an effective treatment approach. In DBS treatment technique, the functional region which is thought to be in a causal relationship to the brain disorder is stimulated electrically in order to suppress disease symptoms (such as involuntary movements). The advantage of functional surgery technique DBS with respect to alternative radical treatment approaches such as functional radiosurgery, which is emerging in the very recent years, is that DBS is reversible and adjustable. Accurate and reliable localization of the brain nuclei, which are relevant to the related functional disorder, is one of the primary problems in DBS treatment and disease follow-up processes.

In this project, we develop novel joint diffusion and functional Magnetic Resonance Imaging (MRI) analysis techniques in order to localize functional brain nuclei (such as SubThalamic Nucleus-STN) not solely based on anatomical connections but rather with multi-modal images through fusion. One of the novel contributions of the project is the joint utilization of Diffusion MRI, which is the only technique that facilitates imaging of anatomical connectivity networks in in vivo human brain, in addition to the recent resting-state functional MRI (rs-fMRI), which makes it possible to explore functional connectivity networks non-invasively.

The methodological novelty of the proposed joint image analyis techniques to create structural-functional maps of brain white matter connectivity and functional connectivity networks include combination of the probabilistic tract information obtained from probabilistic tractography of Diffusion MRI with the functional information obtained from dynamic spatial-temporal functional analysis based on rs-fMRI. The STN maps obtained from combined diffusion-functional information will be used in the DBS application.