Aims

To investigate the resting-state functional connectivity (rs-FC) of the subthalamic nucleus (STN), the most frequently used deep brain stimulation (DBS) target for Parkinson’s disease (PD), in different PD phenotypes.

Methods

Clinical data and rs-functional MRI were acquired from 60 PD patients and 60 age- and sex-matched controls. PD patients were divided into two groups: 19 patients eligible for DBS (PD-DBS) and 41 not candidate for DBS (PD-noDBS). A seed-based RS-FC analysis was run between the bilateral STN and the rest of the brain, and compared between groups.

Results

PD-DBS showed a reduced connectivity between bilateral STN and bilateral sensorimotor areas relative to both controls and PD-noDBS patients. On the contrary, PD-DBS patients showed an increased connectivity between bilateral STN and globus pallidus, putamen and thalamus bilaterally compared to healthy controls. Similar pattern were found when PD-noDBS patients were compared to controls (albeit with lower connectivity levels than PD-DBS patients).

Conclusions

Our results suggest that functional connectivity of deep nuclei changes among PD phenotypes and confirm an important role of functional MRI as tool for selection of candidates for DBS. The idea that STN-DBS works by modulating and restoring functional connectivity between basal ganglia and sensorimotor areas is further corroborated.

Supported by. Ministry of Education, Science, and Technological Development of the Republic of Serbia [grant number #175090]; Italian Ministry of Health [grant number # RF-2018-12366746].