Functional MRI test-retest reliability during deep brain stimulation in Parkinson’s disease

Motivation: fMRI studies are advancing DBS biomarker development, but data reproducibility is unclear. Goal(s): To evaluate resting-state fMRI reliability in 16 patients with DBS for Parkinson’s disease. Approach: fMRI was repeated for DBS-ON and DBS-OFF conditions. Test-retest connectomes were correlated to measure reproducibility and compared across DBS conditions and clinical parameters. Signal reproducibility around the leads was also explored. Results: Stimulation reduced reproducibility around the leads and across multiple networks, differing by brain target. Patients with less tremor and/or more rigidity and bradykinesia, and relative lower symptom and brain response to DBS had more reproducible functional connectivity. Impact: The results enhance our understanding of the reliability of resting-state fMRI derivatives in the presence of DBS leads and during stimulation. Realizing the reliability of these data is critical to clinical translation of fMRI-based biomarkers to improve the DBS strategy.