Longitudinal recordings of local field potentials in movement disorder patients implanted with deep brain stimulation electrodes

Deep brain stimulation (DBS) has been one of the most important therapeutic
development for patients with advanced Parkinson*s disease, tremor syndromes
and dystonia in the past 30 years. Novel developments in DBS devices provide
the opportunity to longitudinally record neurophysiological signals from
implanted brain regions. This is crucial to better understand the therapeutic
effect of DBS, and for the development of so called adaptive deep brain
stimulation (aDBS). This novel method concurrently measures biomarkers related
to severity of symptoms, and adjusts stimulation based on these signals.
Comparing these longitudinally recorded signals with symptom control and
stimulation parameters will help to improve the clinical efficacy of DBS for
patients, and aid in individualised therapy.

Compare neurophysiological biomarkers with symptom control and stimulation
parameters to improve stimulation settings for individual patients with
Parkinson*s disease, tremor syndromes and dystonia.

This is a longitudinal prospective cohort study that will include patients with
three types of movement disorders: Parkinson*s disease, tremor and dystonia who
are implanted with a new DBS device (Medtronic Percept* PC neurostimulator) as
part of standard clinical care. This study will consist of three parts,
patients can opt out for part B/C or part C on an individual basis.
Part A (study visit 1): 15-minute recordings with stimulation switched OFF and
ON. Patients will be invited for participation in this study at least 1 week
after surgery.
Part B (study visit 2 and 3): 15-minute recordings with stimulation switch OFF
and ON. Read out of recordings of the previous 4 weeks saved on the
neurostimulator during two standard visits at the outpatient clinic, or through
two additional visits to the outpatient clinic if no standard visit is
scheduled or necessary.
Part C (surveys, decision-making paradigm, LFP recording, smartwatch - at home
for 2 weekssmartwatch and patient journal at home for 4 weeks in between visit
2 and 3): Between visit 1 and 2, or 2 and 3, patients will fill in a digital
diary for a 4-week period prior to their visit. They will do this on the DBS
patient programmer device. They will also wear a smartwatch for a 4-week period
to measure symptom severity. twice a day (once with stimulation on, and once
with stimulation off) patients will administer surveys indexing PD motor and
non-motor symptoms, perform a decision-making paradigm assessing motivational
state, and trigger a broadband local field potential (LFP) recording via their
DBS programmer. Kinematics and narrowband LFP recording will be collected
passively and continuously via a smartwatch and the DBS device respectively.

Due to the very specific aim of this study, only patients suffering from
advanced Parkinson*s disease, tremor or dystonia can participate. Readout of
recordings is safe and non-invasive. Switching DBS off might be bothersome for
patients as symptoms will temporarily increase during this time period, which
will be limited to 30 minutes. Extra visits to the outpatient clinic might be
involved.