ABSTRACT
Background:
Freezing of
gait (
FOG) is a debilitating symptom of
Parkinson's disease (PD) that is often refractory to medication. Pathological prolonged beta bursts within the
subthalamic nucleus (STN) are associated with both worse impairment and
freezing behavior in PD, which are improved with
deep brain stimulation (DBS). The
goal of the current study was to investigate the feasibility,
safety, and tolerability of beta burst-driven adaptive DBS (aDBS) for
FOG in PD.
Methods:
Seven individuals with PD were implanted with the investigational Summit™ RC+S DBS system (Medtronic, PLC) with leads placed bilaterally in the STN. A PC-in-the-loop
architecture was used to adjust stimulation amplitude in real-
time based on the observed beta burst durations in the STN. Participants performed either a harnessed stepping-in-place task or a free
walking turning and
barrier course, as well as clinical motor assessments and instrumented
measures of
bradykinesia, OFF stimulation, on aDBS, continuous DBS (cDBS), or random intermittent DBS (iDBS).
Results:
Beta burst driven aDBS was successfully implemented and deemed safe and tolerable in all seven participants.
Gait metrics such as overall percent
time freezing and mean peak shank angular velocity improved from OFF to aDBS and showed
similar efficacy as cDBS.
Similar improvements were also seen for overall clinical motor impairment, including
tremor, as well as quantitative
metrics of
bradykinesia.
Conclusion:
Beta burst driven adaptive DBS was feasible, safe, and tolerable in individuals with PD with
gait impairment and
FOG.